Skip to main content

Full text of "North Carolina Geological Survey"

See other formats


J 


£- 


Norfh  Carolina  State  Library 
Raleigh 

NORTH    CAROLINA    GEOLOGICAL    SURVEY 


J.  A.  HOLMES,  STATE  GEOLOGIST. 


l-  = 


BULLETIN  No.  9 


MONAZITE,      AND     MONAZITE     DEPOSITS 
IN  NORTH  CAROLINA. 

BY 

HENRY  B.  C.  NITZE, 

Assistant  Geologist. 


WINSTON : 
M.  I.  &  J.  C.  Stewart,  Public  Printers. 

1895. 


I 


A 


r 


TABLE  OF  CONTENTS. 


PAGE 

Letter  of  Transmittal 5 

Brief  Description  of  the  Mineral 6 

Historical  Sketch  and  Nomenclature 6 

Crystallography 10 

Morphological 10 

Physical 12 

Optical 13 

Chemical  Composition '. 14 

Composition  and  analyses 14 

Method  of  analysis 21 

Chemical  and  blowpipe  reactions 22 

Micro-chemical  reactions 23 

Spectroscopic  tests 23 

Chemical  molecular  constitution 24 

Artificial  production 25 

Geological  and  Geographical  Occurrence. 25 

Accessory  minerals , 30 

Economical  Use 30 

Methods  of  Extraction  and  Concentration 31 

Output  and  Value  of  Monazite  in  the  United  States 35 

Bibliography 38 

Index 44 


ILLUSTRATIONS. 

Plate      I.  Prospecting  for  and  mining  monazite  sand Frontispiece 

"         II.  Map,  showing  workable  monazite  area  in  the  Carolinas...     28 
"       III.  Washing  stream  gravel  for  monazite,   Lattimore  mine, 

Cleveland  county,  N.  C 30 

"        IV.  Mining  and  washing  gravel  beds  for  monazite,  Lattimore 

mine,  Cleveland  county,  N.  C 33 

V.  Mining  and  washing  hillside  soil  for  monazite,   Pheifer 

mine,  Cleveland  county,  N.  C 34 


L 


LETTER  OF  TRANSMITTAL. 

Raleigh,  N.   C,  June  1st,  1895. 

To  His  Excellency,  Hon.  Elias  Carr, 

Governor  of  Worth  Carolina. 
Sir  : — I  have  the  honor  to  submit  for  publication  as  Bulletin  9 
of  the  Geological  Survey,  a  preliminary  report  on  Monazite  and 
Monazite  Deposits  in  North  Carolina,  by  Mr.  Henry  B.  C.  Nitze. 
The  publication  of  this  bulletin  will  serve  as  an  answer  to  the 
many  enquiries  received  by  the  Survey    for  information   on   this 

subject. 

Yours  obediently, 

J.  A.  Holmes, 

State  Geologist. 


MONAZITE 


By  H.   B.   C.  JSIitze. 


BRIEF  DESCRIPTION  OF  THE  MINERAL. 

Monazite  is  essentially  an  anhydrous  phosphate  of  the  rare 
earths  cerium,  lanthanum,  and  didymium  (  Ce,  La,  Di ),  P04.  It 
also  contains,  almost  invariably,  small  percentages  of  thoria  (Th02) 
and  silicic  acid  ( Si02),  which  may  be  present  in  combination  as 
thorite  or  orangite  (  ThSiOJ,  or  the  thoria  may  exist  as  the  phos- 
phate, either  in  combination  with  the  cerium,  etc.,  or  as  an  isomor- 
phous  mixture.  Other  occasional  accessory  constituents  are  the 
yttrium  and  erbium  earths,  zirconia,  alumina,  magnesia,  lime,  iron 
oxides  ( Fe203  and  FeO ),  manganous  oxide,  tin  and  lead  oxides, 
fluorine,  titanic  acid,  and  water,  usually  in  fractional  percentages. 

It  is  a  subtranslucent  to  subtransparent  mineral,  light  yellow, 
reddish  yellow,  brownish,  or  greenish  in  color,  and  has  a  resinous 
luster.  It  is  brittle  with  conchoidal  to  uneven  fracture.  Its  hard- 
ness is  from  5  to  5.5,  and  its  specific  gravity  from  4.9  to  5.3.  It 
crystallizes  in  the  monoclinic  system. 

HISTORICAL  SKETCH   AND   NOMENCLATURE. 

The  following  names  have  been  applied  to  the  mineral  by  inde- 
pendent discoverers  and  workers  :  Turnerite,  monazite,  mengite, 
edwardsite,  eremite,  cryptolite,  monazitoid,  phosphocerite,  urdite, 
and  kararfveite.  It  was  not  long,  however,  before  the  identity  of 
these  newly  described  mineral  species  was  recognized,  and  at  the 
present  time  the  general  name  in  use  is  monazite. 

The  name  "turnerite  "  was  given  in  1823  by  A.  Levy1  in  honor 
of  the  English  chemist,  E.  II.  Turner,  in  whose  collection  the  first 
specimens  were  found.  The  locality  of  these  was  Dauphiny.  They 
had  been  classed  as  sphene,  on  account  of  their  color,  accompani- 

!The  Annals  of  Philosophy,  London,  1823,  vol.  5,  p.  841. 


b  MONAZITE,    AND    MONAZITE    DEPOSITS 

ment  ( adularia  and  lamellary  crichtonite ),  and  the  locality  ;  but 
Levy  found  their  hardness  to  be  less  than  that  of  sphene,  and  a 
good  cleavage  in  one  direction.  He  gives  as  the  primary  crystal- 
lographic  form  an  oblique  rhombic  prism  with  differment  dimen- 
sions from  that  of  sphene.  G.  vom  Rath1  has  also  called  attention 
to  the  fact  that  titanite  ( sphene )  may  be  confounded  with  tunerite 
from  general  resemblance.  In  the  fifth  edition  of  his  Mineralogy 
(American  edition,  Boston,  1844)  Phillips  says  that  monazite  is 
occasionally  known  among  mineralogists  under  the  name  of  "  pic- 
tite,"  which  is  one  of  the  early  names  for  titanite,  with  which  it 
was  doubtless  confounded. 

The  date  1823,  then,  may  be  taken  as  that  of  the  earliest  recog- 
nition of  a  new  mineral  species  which  was  later  shown  to  be  iden- 
tical with  monazite.  Thus,  in  1866,  J.  D.  Dana2  demonstrated 
the  identity  between  turnerite  and  monazite  by  similarity  of  crys- 
tal form  and  physical  properties.  No  chemical  examination  of 
turnerite  had  yet  been  made  at  that  time.  In  1870  this  was  sub- 
stantiated by  G.  vom  Rath,3  and  although  he  recognized  the  priority 
of  Levy's  name,  turnerite,  he  did  not  feel  justified  in  abandoning 
the  name  monazite,  inasmuch  as  the  latter  belonged  to  a  chemi- 
cally as  well  as  a  crystallographically  known  mineral,  while  the 
composition  of  turnerite  was  not  yet  so  well  known.  In  1873  Des 
Cloizeaux,4  by  the  orientation  of  the  optical  axes,  and  Pisani,4  by 
the  chemical  determination  of  P205  and  Ce203,  concluded  that 
monazite  and  turnerite  were  the  same  species.  In  1876  Trechmann5 
showed  that  the  optical  properties  of  turnerite  and  monazite  were 
the  same.  In  1826  Menge  discovered  some  crystals  in  the  Ilmen 
mountains,  near  Miask,  Siberia,  which  he  held  for  a  variety  of 
zircon.  Fiedler6  gives  the  more  exact  locality  of  these  specimens 
as  being  not  in  the  Ilmen  mountains  proper,  but  in  their  southern 
extension,  in  the  so-called  Tscheremtchanka.  The  first  scientific 
description  of  these  was  given  by  Breithaupt7  in  1829.  He  gave  it 
the    name,    "monazite"    ( monazit,    monacite),  from   the   Greek? 

iPoggendorff,  Annalen,  1864,  vol.  122,  p.  407. 
2Am.  Jour.  Sci.  vol.  42, 1866,  p.  420. 

spoggendorff,  Annalen,  Erg.-  Ed.  5, 1871:  p.  413;  Sitzungsber.    Bayer.    Akad.    Wiss.,  1S70, 
vol.  2,  p.  271. 
^Zeitscher.  Deutscher.  geol.  Gesell.,  Berlin,  vol.  25, 1873,  p.  568. 
5Xeues  Jahrbuch,  1876,  p.  593. 
epoggendorff,  Annalen,  1832,  vol.  25,  p.  332. 
7Schweigger-Seidel,  Journal  der  Chenrie  u.  Physik,  1829,  vol.  55,  part  3,  p.  301 


IN    NORTH    CAROLINA.  9 


meaning  "  to  be  solitary."  In  1831  H.  J.  Brooke1,  in  describing 
specimens  from  Menge's  locality  in  the  Urals,  gave  the  name  men- 
gite,  in  honor  of  the  discoverer. 

Prof.  C.  U.  Shepard2  in  1837  gave  a  description  of  "  edwardsite," 
a  new  mineral  from  Norwich,  Connecticut,  which  he  named  in 
honor  of  the  governor  of  the  State.  Later  in  the  year3  he 
described  another  new  mineral  from  Watertown,  Connecticut, 
under  the  name  of  "  eremite,"  after  the  Greek,  meaning  "  soli- 
tude," but  he  did  not  then  recognize  its  identity  with  edwardsite. 
Prof.  J.  D.  Dana  published  in  1838  his  crystallographic  measure- 
ments of  eremite,  which  agree  with  those  of  monazite.4  In  1840 
Gustav  Rose5  proved  the  identity,  crystallographically  and  physi- 
cally, of  edwardsite  and  monazite.  And  in  the  second  edition  of 
his  Mineralogy  (1814)  Shepard  places  both  edwardsite  and  eremite 
under  the  head  of  monazite. 

In  1842  Rose6  gave  a  detailed  description  of  the  Russian  mona- 
zite. 

Woehler,7  in  1846,  discovered  some  small  needle-like  crystals 
invisibly  included  in  the  apatite  of  Arendal,  Norway.  They  were 
of  a  pale-yellow  color,  specific  gravity  approximately  4.6,  and,  accord- 
ing to  analysis,  were  composed  of  phosphate  of  cerium,  but  contained 
no  thoria,  and  in  this  he  distinguished  the  mineral  from  monazite, 
calling  it  "cryptolite,"  from  the  Greek,  meaning  "concealed." 
Although  the  forms  of  these  crystals  are  different  in  appearance 
from  that  of  ordinary  monazite,  Mallard,8  in  1887,  by  careful  gonio- 
metric  measurements,  established  the  identity  of  the  two  minerals. 

Hermann,9  in  1847,  applied  the  name  "monazitoid"  to  certain 
brown  colored  bent  and  broken  crystals,  of  the  specific  gravity  5.28, 
from  Lake  Ilmen,  near  Miask,  which  contain  less  phosphoric  acid 
(only  18.7)  than  monazite,  besides  some  tantalic  acid  (3.75  to  6.27 
per  cent).   Kokscharow10  believed  that  monazitoid  was  simply  impure 

iPoggendorff,  Annalen,  1831,  vol.  23,  p.  362;  Philos.  Mag.  and  Annals,  vol.  10,  p.  187. 

2Am.  Jour.  Sci.  (1),  1837,  vol.  32,  p.  162;  Poggendorfl,  Annalen,  1838,  vol.  43,  p.  148. 

3Am.  Jour.  Sci.  (1),  1837,  vol.  32,  p.  341. 

4  Am.  Jour.  Sci.  (1),  vol.  33, 1838.  p.  70. 

5Poggendorff,  Annalen,  1840,  vol.  49,  p.  223. 

6Reise  nach  dem  Ural  und  Altai,  voJ.  2,  p.  87  and  482,  Berlin,  1812. 

^Poggendorff,  Annalen,  1846,  vol.  67,  p.  424. 

8Bull.  Soc.  Min.,  1887,  vol.  10,  p.  236. 

9Jour.  prakt.  Chemie,  vol.  40, 1847,  p.  21;  Annuaire  de  Chemie,  1848,  pp.  14'i. 

10Materialien  zur  Mineralogie  Russlands,  vol.  4, 1862,  pp.  7-34. 

2 


10  MONAZITE,  AND    MONAZITE    DEPOSITS 

monazite,  the  tantalic  acid  haying  been  derived  from  columbite  and 
samarskite,  with  which  the  crystals  are  intergrown. 

Blomstrand1  analyzed  specimens  from  probably  the  same  locality 
as  Hermann's  monazitoid,  but  found  no  tantalic  acid. 

In  1850  Watts2  described  a  new  mineral  occurring  in  the  cobalt 
ore  of  Johannisberg,  Sweden,  which  he  showed  to  be  a  phosphate 
of  cerium  (including  lanthanum  and  didymium).  He  proposed  the 
name  "phospho-cerite."  Its  physical  and  chemical  characters  iden- 
tify it  beyond  doubt  with  monazite. 

Forbes  and  Dahll,3  in  1855,  described  a  mineral  occurring  in  the 
granite  of  Urda,  near  Notero,  Norway,  under  the  name  of  "urdite," 
which  E.  Zschau4  determined  to  be  monazite. 

F.  Radominski,5  in  1874,  found  a  mineral  inclosed  in  albite  at 
Kararfvet,  near  Falun,  Sweden,  which  resembled  monazite,  but  on 
analysis  was  found  to  contain  a  notable  quantity  of  fluorine  (4.35 
per  cent),  and  for  that  reason  he  proposed  to  class  it  as  a  separate 
species  under  the  name  "kararfveite."  Blomstrand6  made  an  analy- 
sis of  specimens  from  the  same  locality,  and  found  only  0.33  per 
cent,  fluorine.  He  concluded  that  it  was  but  an  impure  form  of 
monazite. 

CRYSTALLOGRAPHY. 

MORPHOLOGICAL. 

The  primary  form  of  monazite  and  its  equivalents,  turnerite, 
edwardsite,  and  mengite,  was  early  stated  to  be  the  oblique  rhom- 
bic prism  of  the  monoclinic  system.  The  crystallographic  studies 
of  the  mineral  by  Koksharow,  Des  Cloizeaux,  Websky,  Dana,  Tom 
Rath,  and  others  have  shown  the  occurrence  of  the  following  forms: 

^eitschr.  fur  Kryst.,  vol.  20, 1892,  p.  367,  Lunds  Universitets  Arskrift,  1888  (24). 
2Quart.  Jour.  Chem.  Soc.  London,  1850,  vol.  2,  p.  131. 

Xyt  Mag.  Naturvidenskaberne,  vol.  8, 1855,  p.  227;  Am.  Jour.  Sci.,  vol.  22, 1856,  p.  262 
4Allg.  deutsche  naturh.  Zeitung,  Dresden,  1857,  p.  208;  Am.  Jour.  Sci„  II,  vol.  25, 1858  p  410 
5Compt.  Rend.,  1874,  vol.  78,  p.  764. 

,;Zeitsch.  fur  Kryst.  vol.  19, 1891,  p.  109;  Geol.  Foreningens  Forhandl.  Stockholm,  1889.  vol 
2,  p.  174. 


IN    NORTH    CAROLINA. 


11 


Observed  forms  of  monazite. 


Pinacoids. 

Prisms. 

Hemi- 
domes. 

Hemi-pyra- 
mids. 

oP 

ocP 

+   Poo 

+  P 

<*P^ 

00P2 

_   Po^ 

—  P 

OoPod 

00P3 

— 7Pco 

-HP 

00P2 

-|Poo 

—IP 

P^O 

+  Pa 

SPcX, 

+2P§ 

iPob 

+3Ps 

+2P3 
— 2P3 

Of  these,  the  more  common  forms  are  the  ortho-  and  clino-pina- 
coids  and  domes,  the  unit  prism,  and  the  unit  pyramids.  The  basal 
pinacoid  is  rare,  having  been  observed  only  on  crystals  from  the 
Urals1  and  from  Alexander  County,  N.  C.2 

Among  the  rarer  forms  are:  — |P~ol>  found  by  Trechmann  on  tur- 
nerite  from  the  Einnenthal,  Switzerland;  —  TP^o  and  —  ^P,  found 
by  Miers  in  Cornwall;  and  i-P^oo,  on  crystals  from  Nil  St.  Yincent, 
Belgium,  and  western  Siberia. 

The  usual  crystal  habit  is  tabular,  parallel  to  00  P~ob;  also  short 
columnar,  and  sometimes  elongated  parallel  to  00  P.  Cryptolite 
occurs  always  in  very  small  crystals,  elongated  parallel  to  x>  P. 
The  crystals  are  usually  well  developed  and  free  from  distortion. 
They  vary  in  size  from  the  microscopic  needles  of  cryptolite,  wrhich 
have  a  thickness  of  .004  to  .016  mm.  (0.00015  to  0.00062  inch),  to 
the  abnormally  large  monazite  crystals  that  have  been  found  in 
Amelia  County,  Va.,  5  inches  in  length.  The  more  general  varia- 
tion lies  between  one  twentieth  and  1  inch.  Irregular  masses  of 
monazite,  devoid  of  crystal  planes,  as  large  as  15  to  20  pounds,  have 
been  found  in  Amelia  County,  Ya.,  and  in  rounded  masses  up  to 
12|  pounds  at  the  Yilleneuve  mica  mine  in  Ottawa  County,  Quebec. 

Twins  are  not  common.  The  twinning  plane  is  parallel  to  00  P  ^5; 
als.o  to  oP  (Zirkel,  Yol.  I,  p.  432.)  Twins  are  sometimes  cruci- 
form. 

1N.  von  Koksharow,  Materialien  zur  Mineralogie  Russlands,  vol.  4, 1862,  pp.  7-34. 
2G.  von  Rath,  Zeitschr.  fur  Kryst.,  vol.  13, 1888,  p.  596. 


12 


MONAZITE,    AND    MONAZITE    DEPOSITS 


The  axial  ratio  has  been  determined  on  specimens  from  different 
localities,  as  follows: 

Axial  ratios  of  monazite  from  various  localities. 


a 

h 

G 

/3(oPA°oPob) 

0.9742 

1 

0.9227 

o            / 

103    46 

0.9705 

1 

0.9221 

103    46 

0.9658 

1 

0.9217 

103    28 

0.9609 

1 

0.9081 

103    26^ 

0.9693 

1 

0.9255 

103    40 

0.9735 

1 

0.9254 

103    37 

0.9718 

1 

0.9233 

103    42 

Localities. 


Determined 
by- 


Watertown,  Conn,  (eremite) J.  D.  Dana. 

Ural  Mountains,  Sanarka Koksharow. 

Laacher  See  (turnerite) Vom  Rath. 

Hiddenite  mine,  N.  C. Do. 

Milhollands  Mill,  N.  C  E.  S.  Dana. 

Schiittenhofen,  Bohemia j  Scharizer. 

Nil  St.  Vincent Franck. 


Some  of  the  principal  angular  measurements  are: 
Angular  measurements  of  monazite. 


dPSd/^ccP 

oP/\P» 

ooPoo  A  oP 

eoP£o/\P 

CcPoOy^Pio 

O             /        •/ 

o          •       // 

O              /          '/ 

O           '        s/ 

o          •       s, 

43    25      0 

76    14      0 

39    20      0 

43    18    30 

37    11      0 

76    14      0 

59    37      0 

39    03      0 

43    12    30 

37    12    30 

76    32      0 

59    42    30 

39    20    30 

43    17    10 

37    07    40 

76    20      0 

59    40      0 

39    12    30 

43    25      0 

37    03      0 

76    23      0 

59    36      0 

39    20      0 

Localities. 


Measured 

DV— 


Watertown,Conn., 
(eremite). 

Ural  Mountains, 
Sanarka. 

Laacher  See  (tur- 
nerite). 

Milhollands  Mill, 
N.  C 

Schiitten  h  o  f  e  n , 
Bohemia. 


J.  D.  Dana. 
Koksharow. 


Vom  Rath. 
E.  S.  Dana. 


Scharizer. 


PHYSICAL    CRYSTALLOGRAPHY. 


The  cleavage  is  most  perfectly  developed  parallel  to  the  basal 
pinacoid  (oP.);  it  is  also  distinct  as  a  rule  parallel  to  oo  P^o  ;  some- 
times parallel  to  ooPoo  ,  imperfect;  parallel  to  — Poo  (noticed  by 
Vom  Path  on  turnerite  from  Laacher  See1).  Parting  is  sometimes 
developed  parallel  to  oP  and  oo  P.  It  is  brittle  with  a  conchoidal 
to  uneven  fracture.  The  hardness  is  5  to  5.5.  The  specific  gravity 
varies  from  4.64  to  5.3.  The  luster  is  resinous  to  waxy.  The  crystal 
faces  are  splendent  in  fresh,  pnre  specimens;  dull  in  weathered,  im- 
pure specimens.  The  color  is  honey  yellow,  yellowish  brown,  amber 
brown,  reddish  brown,  brown  or  greenish  yellow.  Derby2  describes 
specimens  of  lusterless,  whitish  grains  in  muscovite  granite  of  Sao 
Paulo,  Brazil,  which  he  proved  to  be  cerium  phosphate. 

iPoggendorff,  Annalen,  1871,  Erg.-Bd.  5,  p.  413;  Sitzungsber.  Bayer.  Akad.  Wiss.  1870,  vol- 
2,  p.  271. 
2Am.  Jour.  Sci.  (3),  vol.  37, 1889,  pp.  109-114. 


IN    NORTH    CAROLINA. 


13 


The  monazitoid  of  Hermann  is  of  a  dark-brown  color,  due  to 
impurities.  In  weathered  specimens  of  impure  monazite  the  sur- 
face is  rough,  dull,  and  sometimes  covered  with  a  light-brown  earthy 
substance. 

The  purest  specimens  of  mon  azite  are  transparent,  becoming  trans- 
lucent and  even  totally  opaque  in  the  impure  varieties. 

It  is  frequently  difficult  to  distinguish  monazite,  in  fine  grains, 
from  certain  other  minerals  by  the  uninitiated  eye.  Some  varieties 
of  yellowish-brown  quartz  are  quite  easily  confounded  with  mona- 
zite; so  also,  at  times,  sphene,  zircon,  epidote,  corundum,  etc.  For 
the  benefit  of  the  unscientific  prospector  it  may  be  stated  that  the 
chief  macroscopic  distinctions  are  those  of  color,  hardness,  and  speci- 
fic gravity.  The  color  is  usually  yellowish,  inclined  to  reddish, 
brownish,  or  more  rarely  greenish  tints.  The  fresh  unaltered  grains 
are  transparent  or  translucent.  The  larger  crystals  are  frequently 
dull  in  luster  and  opaque. 

The  hardness  is  from  5  to  5.5,  between  that  of  apatite  and  ortho- 
clase  (feldspar).  Thus  it  can  be  scratched  by  a  fragment  of  ordi- 
nary feldspar,  (hardness  6)  or  quartz  (hardness  7).  The  hardness  of 
sphene  is  5  to  5.5,  of  zircon  T.5,  of  epidote  6  to  7,  of  corundum  9. 
The  specific  gravity  of  monazite  is  4.64  to  5.3;  that  of  quartz  is  only 
2.6,  of  sphene  3.5,  of  zircon  4.7,  of  epidote  3.25  to  3.5,  of  corundum 
3.95  to  4.10. 


OPTICAL    CRYSTALLOGRAPHY. 

Thin  sections,  by  transmitted  light,  are  colorless  to  yellowish. 
Pleochroism  is  generally  scarcely  noticeable.  Absorption  b  >  C  =  a. 
The  plane  of  the  optic  axes  is  perpendicular  to  the  plane  of  sym- 
metry qo  P"oo.  The  positive  acute  bisectrix  lies  in  the  obtuse  angle 
/?;  hence  sections  parallel  to  oP  show  the  full  interference  figure. 
Optical  measurements  of  monazite. 


b=h 


c  Ac=l 


04 
3  00 
3  46 
5    54 


Localities. 


(Turnerite)  Tavetsch,  Switzerland 

Arendai,  Norway 

Norwich,  Connecticut 

Schiittenhofen,  Bohemia 


Measured  by 


Trechmann. 

Wiilfing. 

Des  Cloizeaux. 

Scharizer. 


I 


n 


MONAZITE,    AND    MONAZITE    DEPOSITS 


The  opitcal  angle  is  small;  various  measurements  give: 
Optical  measurements  of  monazite. 


2  E(red) 

2E(yel- 
low). 

2E(vio- 
let). 

2V 
(red). 

2  V  (yel- 
low). 

Disper- 
sion. 

Localities,  etc. 

o             / 

29    04 

o           / 

o             / 

28    48 
31     43  \ 

o              / 

o             / 

p>v 

p<y 
P>v 

Norwich, Conn.,  Des  Cloi- 
zeaux. 
Sibera,  Des  Cloizeaux. 

31     08i 

25     22 

24     56 

28     25 

12  44 
14    29 

Schuttenhof  en,  Bohemia, 

Scharizer. 
Pisek,  Bohemia,  Vrba. 

29     07 

14    50 

34    12 

p<v 

Turnerite,    Tavetsch, 

Trechmann. 

The  dispersion  is  weak  and  horizontal.      The  single  refraction  ii 
high;  double  refraction  considerable. 

Optical  measurements. 


a 

P 

7 

y—a 

y-13 

(3 — a 

Localities,  etc. 

1.9285 

1.9465 
1.7965 

\ 

Schiittenhofen,      Bohe- 

1.7957 

1.8411 

0.0454 

0.0446 

0.0008 

mia,  Scharizer. 
Arendal,      ISTorway,     E. 
Wiilfing. 

CHEMICAL    COMPOSITION. 

COMPOSITION    AND    ANALYSES. 

The  earlier  discoverers  had  very  little  knowledge  of  the  true 
chemical  composition  of  monazite.  Breithaupt,1  in  1829,  concluded 
from  the  high  specific  gravity  of  the  Siberian  monazite  that  it  was 
a  metallic  oxide  or  acid  in  combination  with  some  of  the  earths. 
Shepard2  stated  in  1835  that  monazite  was  inferred  to  consist  of 
the  oxide  of  uranium  with  some  one  or  more  of  the  earths  (accord- 
ing to  blowpipe  tests  of  Breithaupt).  At  the  same  time  turnerite, 
according  to  blowpipe  experiments  of  Mr.  Children,  was  supposed 
to  contain  chiefly  A1203,  CaO,  MgO,  and  a  little  iron,  with  traces 
of  Si02.  In  1837  Shepard  published  an  analysis  of  his  edwardsite  (see 
table,  anal.  No.  29,  p.  19),  in  which  he  first  pointed  out  the  existence 
of  cerium.     He  deduced  the  relationship  P205:  CeO=l:  1  J,  making 

^chweigger— Seidel,  vol.  55, 1829. 

-Treatise  on  Mineralogy,  1st  edition;  vol.  2, 1835. 


IN    NORTH    CAROLINA.  15 

the  mineral  a  basic  sesqui-phosphate  of  cerium  protoxide.  He  also 
found  7.77  per  cent  Zr02,  but  it  is  doubtful  whether  this  is  an  origi- 
nal constituent;  more  probably  it  may  be  referred  to  the  presence 
of  the  mineral  zircon  as  an  impurity  in  the  sample,  which  is  an 
almost  constant  accompaniment  of  monazite.  He  found  further, 
A1203,  Si02,  FeO,  MgO,  and  a  trace  of  glucina. 

Kersten,1  in  1839,  analyzed  the  specimens  from  the  Ural  Moun- 
tains, previously  determined  by  Breithaupt  to  be  a  combination  of 
uranium  oxide  with  some  of  the  earths,  but  found  no  trace  of  uran- 
ium. He  did  find  it  to  be  essentially  a  phosphate  of  cerium  and 
lanthanum  oxides,  and  was  the  first  to  show  the  presence  of  La203, 
Th02,  Sn02,  MnO,  CaO,  and  traces  of  Ti02,  and  K20.  (See  table, 
anal.  No.  20,  p.  18.) 

In  1846  Woehler2  published  an  analysis  of  cryptolite  from  Aren- 
dal,  Norway,  determining  it  to  be  a  phosphate  of  cerium  oxide. 
(See  table,  anal.  No.  21,  p.  18.)  He  could  find  neither  Zr02  nor  Th02, 
from  which  he  concluded  that  the  absence  of  Th02  distinguished 
cryptolite  from  monazite  and  ed  ward  site. 

In  1847  Hermann3  came  to  the  conclusion  that  monazite  was  the 
neutral  phosphate  of  cerium,  in  which  a  large  part  of  the  cerium 
was  replaced  by  lanthanum  and  a  small  part  by  CaO,  MgO,  and 
MnO  in  the  varieties  of  lighter  specific  gravity,  while  the  heavier 
varieties  (sp.  gr.  5.281)  contained  less  P205,  and  a  large  part  of  the 
stannic  acid  was  replaced  by  tantalic  acid  (Ta205).  (See  table, 
anal.  No.  17,  p.  1 8.)  This  variety  he  called  monazitoid,  which  occurs 
at  Lake  Ilmen,  near  Miask,  Siberia.  It  is  of  a  dark-brown  color  as  dis- 
tinguished from  the  lighter  color  of  monazite.  At  first  Hermann 
denied  the  presence  of  thoria  in  monazite  and  monazitoid,  but  later 
he  found  as  high  as  32.44  per  cent  Th02  in  a  specimen5.  (See  table, 
anal.  No.  19,  p.  1 8.)  Monazite  and  monazitoid,  he  says,  have  the  same 
form,  and  are  therefore  heteromeric,  having  different  composition. 
Like  all  heteromeric  minerals  they  show  a  tendency  to  mix,  and  thus 
give  a  series  with  slight  difference  in  specific  gravity.  Koksharow4 
believed  that  monazitoid  was  simply  an  impure  variety  of  monazite, 

iPoggendorff,  Annalen,  vol.  47,  1839,  p.  385. 

2Poggendorff,  Annalen,  vol.  67, 1846,  p.  424. 

3Jour.  prakt.  Chemie,  vol.  40. 1847,  p.  21. 

4Materialien  zur  Mineralojiie  Russlauds,  vol.  4, 1892,  pp.  7-34. 

5It  is  highly  probable  that  the  greater  part  of  this  w  as  lanthanum. 


/ 


16  MONAZITE,    AND    MONAZITE    DEPOSITS 

where  the  tantalic  acid  was  derived  from  columbite  and  samarskite, 
in  which  the  crystals  of  monazitoid  were  intergrown,  and  this 
appears  most  probable.  Blomstrand1,  in  his  analysis  of  specimens 
from  the  Ilmen  Mountains  (same  locality  as  Hermann's  monazitoid), 
found  16.64  per  cent  Th02,  but  no  tantalic  acid.  (See  table,  anal. 
No.  15,  p.  18.) 

In  1850  Watts2  published  an  analysis  of  his  phosphocerite,  which 
he  determined  to  be  a  phosphate  of  cerium  protoxide,  including 
lanthanum  and  didymium. 

Websky,3  in  1865,  in  making  blowpipe  tests  on  monazite  from 
the  Riesengebirge,  found  cerium,  phosphoric  acid,  and  titanic  iron; 
the  latter,  however,  must  have  been  an  impurity  in  the  powder, 
probably  from  the  ilmenite,  which  is  mentioned  as  occurring  as  an 
associated  mineral  in  this  locality. 

Radominsky's  variety  of  monazite,  kararfveite,  from  Sweden,  was 
found  by  him  to  contaiu  4.33  per  cent  fluorine4.  (See  table,  anal.  No. 
16,  p.  18.)  Blomstrand's  analysis  of  a  specimen  from  the  same  local- 
ity showed  only  0.33  per  cent  fluorine.  (See  table,  anal.  No.  11, 
p.  IT,)  and  he  concluded  that  the  so-called  kararfveite  was  simply  an 
impure  variety  of  monazite. 

Scharizer5  first  pointed  out,  in  1887,  the  presence  of  an  element 
of  the  erbium  group  in  the  monazite  from  Schiittenhofen,  Bohemia. 
His  determination  was  made  on  a  thin  section  by  means  of  a  spec- 
troscopic attachment  to  the  microscope. 

Genth,6  in  1889,  published  an  analysis  of  monazite  from  the  Yille- 
neuve  mica  mine  in  Canada,  in  which  he  determined  4.76  per  cent 
of  (Y,  Er)2  03.     (See  table,  analysis  No.  37,  p  20.) 

Blomstrand,7  in  1889,  also  showed  the  presence  of  yttrium  in  the 
monazite  from  southern  Norway;  and  he  first  pointed  out  here  the 
presence  of  lead  oxide. 

Below  is  given  a  table  containing  a  number  of  analyses  of  mona- 
zite from  various  localities,  with  references: 

iZeltschr.  fur  Kryst.,  vol.  20, 1892,  p.  367. 
2Quart.  Jour.  Chem.  Soc.  London,  vol.  2,  U-50,  p.  131. 
-Zeitsehr,  Deutsch  geol.  Gesell.,  Berlin,  vol.  17, 18<>5,  p.  567. 
*Compte  Rendu,  vol.  78, 1874,  p  764. 
5Zeitschr.  liir  Krvst,  vol.  12,  1887.  p.  255. 

GAm.  Jour.  Sci.,  vol.  38, 188'.*,  p.  203;  Zeitschr,  fur  Kryst.,  vol.  19.  1891,  p.  88. 
7Zeitschr.  fur  Kryst.,  vol.  15,  1889,  p.  99;  Geol.  FSreningens,  Forhandl.,  Stockholm,  vol.  9, 
1887,  p.  160. 


IN    NORTH    CAROLINA. 


17 


CO 


o 

< 


CO 

<^> 
co 


CO 

T-H 

OS  CO  OC 

lO  CD  Tj 

CO  OS  cc 
CO  CO  <N 

2.54 

10.39 

2.16 

JO 

00 
00 

T— 

cc 

03 

JO 

tH 

T-l 

25.56 
37.92 

20.76 

MHQOrt 

xco-^tjj 

00  CO 

CO 
CO 

tH 

co  ^  oo 

tH  CO  CO 

lO 
CO 

T-H 

o 

T-l 

27.28 
30.46 
24.37 

1.58 

11.57 

2.02 

O^lO 

t-H  CO  o 

T-H          tH 

00  CD 
O  CI 

GO 
CO 

9 

23.85 
27.73 
21.96 

CO  lO  io 
GO  O  OS 

CO  OS  lO 

CO 

co 

CO 
00 

CD 
CD 

1—1 

CD 
1—1 

8 

28.94 
30.58 
29.21 

GO  -*  CQ  GO  CO 
i>  tH 

OS 

T-l 
T-l 

CO 
CO 

OS 

o 

7 

27.55 
29.20 
26.26 

(M  J>  CO 

GO  JO  00 

00  OS  T-l 

CO 
T-H 

T-H 

OS 
CO 

CO 

to 

CO 

27.99 
30.98 
25.88 

CO  CO  00 
CO  OS  t-H 

jo 

CO 

T-l 

JO 
JO 

o 

C3 

lO 

28.27 
28.06 
29.60 

CO  'HH  JO  CO  CO 
GO  CO  CO  T-l  CO 

1— 1    OS  T— 1 

00 

1— 1 

CO 

"* 

26.37 
31.23 
24.51 

co  o  o 

T-l  OS  CO 

OS 
T-H 

00  CO  CO 
(M  OS  T-H 

T— 1 

CO 

CO 
JO 

T-H 

3 

27.07 
25.82 
30.62 

COOOIOH 
O  CD  GO  t-H  O 

CO  OS  T-H          T-H 

oo  T-i  co 

O  OS  o 

00 

jo 

JO 

CO 

2 

29.41 
36.63 

26.78 

T-l  T-l  CO  CO  CO 
GO  00  OS  t-H  CO 

tH  CO 

CO 

OS 

o 

GO 

1-i 

tH 

28.62 
32.52 
29.41 

■^h  ^H  t-<  co  co 

O  lO  lO  CO  CO 
CO^H  tH 

00 

CO 

CO 

CO 

c 

p. 

8C 

.  a 
C 

c 

p 

> 

c 
a: 

< 

3c 

c 

c 
1 

c 

s 

S3 

c 

3D 

c 

Ph 

ft 

c 

B 

e 

'2 

c 

o 

t> 

t> 

I— 1 

.- 

s 

GO 

r? 

& 

M 

M 

o 

+3 

s 

m 

Sh 

I 

£5 

T) 

a 

43 

crt 

0) 

^5 

N 

:o 

,14 

R 

I.— 

02 

a 

6n 

d 

J5 

o 

© 

t> 

Sn 

:o 

OJ 

rH 

I— 1 

o 

a 

o 

M 

fl 

o 

ce 

o 

in 

w 

CO 

a 

o 

s 

fl 

« 

03 

£ 

:o 

o 

73 

>> 

£ 

D> 

a; 

be 

l>> 

d 

h 

o 

:o 

£ 

PH 

fl 

o 

0) 

n 

XI 

£ 

o 

'T, 

o 

+-> 

73 

oa 

<H 

a 

t-l 

o 

o 

73 

■?* 

pq 

a 

o 

>  p. 

i 

oq 

+3  x 

o 

^ 

a 

o 

ao 

0; 

a 

a  > 

an 

0+3 

© 

'pBih 

>3 

+3 

0) 

03 

08 

a 

OD^-I 

3C3 

:o 

H* 

M 

X 

Co 

a 

a 

©a 

o 

p 

TH   a) 

OS 

s 

T-l 

rt 

ft 

North  Carolina  Stale  Library 
Raleigh 


18 


MONAZITE,    AND    MONAZITE    DEPOSITS 


r«0 

no 

•<s> 
5> 


^ 


1 


1—1 
03 

CO 

o 

fc- 
CO 

-I— I 
IO 

© 

o 

IO 
X 

o  o 

CO  CO 

OS 
tH 

CD  X 
X  CO 

o 
1—1 

OS 
1—1 

IO 

00 
05 

IO 

X 

JO 

CO 

IO 
CO 

IO 

IO 

T-H 

h 

o 
to 

T-H 

00 

TH 

lOOH 

X  i>  i> 

<N  CO  CQ 

CO  o 
tJI  X 

T-H 

IO 

frj- 

1—1 

OS  CO  CO 
i>  OS  tH 

T-l   TjH    <N 

e 

H 

^ 

1> 

CO 

CO 

CO 

tH 

co 

X 

CO 

i  o 
:  "^ 

;  co 

CO 

io 

CO 

2 
o 

IO 

tH 

CO  X  OS 
tH  X  CO 

OS  C5  -* 
tH  (M  -i— 1 

TH  T*  b-  O 

HCDC3N 
1—1 

CO  OS  IO  o 

IO  X  o^  ^ 

CO^*   tH 

o 

fc- 

1-1 

OS  o  o 

0050 
W  CO  tH 

rawo 

-T-t 

CO 

CO 
CO 

CO 

CO 
IO 

CO 

TH 

WHO 
CO  CO  X 

i>  t-H  tH 

CQ  CO  CO 

'  CQ  to  £>  CO  CO 

10»OCOrH« 

IO 
IO 

IO 

os 

T-l 

c 

- 

>    0 

2 

^c 

:> 

•- 

2< 

-'  c 
IP* 

b 

h 

>> 

Ik 

)C 
3  a 

) 

jc 

:   a 

<E- 

nE- 

5tl 

> 

1 

o<j 


oo 
.►73 

SC  ■r-  . 

P  —  +a 

IS* 

a)  _ro 

s£ 

o 


8   . 

"•3 


-*o 

O    - 

fl  — 

5  "3 


SCO 

-;  i£fl 

-it© 
, --  O  if 

t--  it 
O 


C3v>.  © 

■SOP 


tf     gp^ 


ej  ao  <b  " 

B3  =3     . 


->. 


r    g-2 


©^   CO 
a  tr,  fl 


,Q  i-i  08 

,       fl  £  Ccx>  fl  fl  2, 

xc    o  r  ' 


lEtfSSE 


rH  *  "_  r-i  rH  m  Jfl  — 1  55  *i 


IN    NORTH    CAROLINA. 


19 


i 

55 


S 
Is. 


=0 

so 


OS 

CM 

O  CO 

co  10 

so  co 
CO  io 

co  ^ 

CO  Tj 

CO  Tt 

s 

00 
CO 

0  0 

£-  CO      OS 

00-rH      OS 
CO  CO      CO 

CM 

0 

TH 

OS 
CO 

T*    lO 

CO-* 
TH  CO 

Y 

CO 

-1— 1 
Ol 

00 

0 

00 

CO 

CO 

OS  ^H      tH 

O  CO      CO 

10  CO     0 
CO  CO      CO 

CO  t— 1  tH 
CO  CO  t-i 

tH  CO  CO 

F4 

H 

CO 

0 

TjH  TH  OS 

00  OS  00 
CO  10 

CO 
CO 

co      00 

CO         CO 
OS        t~ 

CO          CO 

10 

OS 
CO 

CO 
CM 

00  cc 

00  £- 

CO  CO 

CO 

OS 
CO 

0 
co 

0 

CO 

0 

OS 

c 

< 

<  a 

c 

1-3 

c 
p 

^c 
k 

c 

< 

'  a 

a 

1 

1 

1 

'c 

£ 

c 

'c 

0       3 

>         n 

a 

\        <\ 

00               o_T 

co          <R 

O 

O 

43               >ti 

> 

_!          M                3 

CO 

1-1      .H           be 
.      W           bj) 

d 

a 

0) 

ft 

© 

n 

1850,  vo 

Zeitschr 

p.  445. 

13. 

.  33,  p.  16 

1! 

CO 

© 

O 

&c 

^'— '  ©    .-i— 51- ' 

,d 

cio-^-d 

0 

£>^^ 

0 

CD 

+2 
Q 

hem. 

,1877 
by  A 
.  Phy 
t.,  188 
Jour. 

0 
I! 

0+2    -a  £?    . 
£>  S  S  h  d 

0 
©' 

Jour 
r  Kr 
Wal 
1.  Ch 
UrK 
d,  A 

N 
bC 

© 

O 

© 

a 
a 

« 

ft 

by  H.  Watts,  Quart. 
Pisani,  Zeitschr.  Jii 
f  Gough,  New  South 
da,  by  Damour,  Am 
Gorcaix.  Zeitschr.  1 
nn.,  by  C.  U.  Shepar 

0 
0 

rg,  Sweden, 
uzerne,  by  F 
om  county  0 
New  Granda 
Brizil,  by  H. 
Norwich,  Co 

08 

-o 

d 

© 

■^ 

nisbe 
om  L 
e.  Fr 

mia, 
ellas, 
from 

3 
0 

§&£S5« 

© 

•-»  E  2  <  O  g 

<& 

d  2-S  d  fl  as 

3 
0 

c^'pp^ 

s 

.faH  olil^H 

ei  5  re  "*  1~  t-  X  C5 
K    .©4  04  55  ©4  04  53 

20 


MONAZITE,    AND    MONAZITE    DEPOSITS 


3 

5 


<s 


V- 


53 


CO 

o  o 

00  00 

CO  ^H 
Oi  OJ 

TH 

CO 
©i 

CO  O-rH 
t-  CO  OS 

^  ©i 

o 
1—1 

lO  c 

TH 

5 

1 

so 

CO 

lO 

cs 
to 

CM 

3 

co 

GO 

JO 

- 

- 

- 

OS 

■\ 

CO 

CO 

-1-H 

©i 

Y 

CO 

lO 

c 
to 

CI 

©5 

00 

CO 

' 

CO 

CO 

©3  CO  O 

CO  CQ   CO 

oi  i>  th 

©i  CO  CO 

00  CO 
■^H  CO 

T— 1 

CO 

©i  OS  CO 

■pH  00   CO 

CO  OS   CO 
©i  ©i   Oi 

CO  lO 
©i  00 

tJH  ©i 

1— 1 

CO 

CO 

00  00  00 
CM  CO  00 

OStH   O 

Oi  CO  CO 

OS  o 

CO  T-\ 

o 

o 

CO 

00  ^   CO 
tHIO  CO 

GO  CO  00 

lO  i> 

©i  co 

GO  tH 

CO 

c 

- 

c 

>  c 

c 
5 

> 

E- 

"5 

< 

'  a 

'A 

IS 

C 

j 

s 

:1 

iC 

) 

C 

c 

fit 

E- 

9 

E- 

'c 

■  .3*  -d* 
•  •  • -sSSrt 

-££  J    -_•- 

en    -   -a»a  P  O     • 

o  -^  *3  "*i  ft  -y-  ft  >■ 


-  j:  -  8  -  ~  = 

—  ~  ~r  22  ~  ~Z 
.  •  x  x    .  x  N  s^ 


£  .  ^ . ,  x  -    • 


jSiidftSS 


O  £.  Q.    .  ^  3^  —  Cl 

L~  —  —  —  X 

nnn=  r  r^'£ 
■  X  X  >  nj  Jg  CO " 
—  X  X     ^=  w»     -o- 

ef  »  ,qiAq  O00 
ooStgacPH  >  >^ 

rJ      r     ^S4i  .-.>? 

O  •"  ,_,    .  as  •-  B  s- 

"SgfcSSif? 

C  l-i  Pi  ?H         H  ,J  c  * 

pk-  .    .O    .    .£b 


x 


o^cc aacc 

.3  c  r  o  coo 

g°  o3  fl  eS  eg  eg  aS 

££2><22a3c3 

PhP5<J^<<CC 

SSSSSBSH 

oooooooo 

U.  U  S-  h  ti  U  fc,  ^ 


1 


IN    NORTH    CAROLINA. 


21 


Below  are  given  the  thoria  contents  of  a  number  of  samples 
from  North  Carolina,  which  were  analyzed  for  the  writer  by  Dr. 
Charles  Baskerville,  assistant  chemist  of  the  North  Carolina  geo- 
logical survey.  These  analyses  are  not  made  on  the  pure  mineral, 
but  on  the  commercial  monazite  sand,  which  contains  up  to  about 
67  per  cent,  monazite,  the  remainder  being  quartz,  garnet,  zircon, 
and  other  accessory  minerals. 

Thoria  contents  of  North  Carolina  monazite  sand. 
[Per  cent.] 


1 

2 

3 

4 

5 

6 

7 

8 

9 

Th02 

0.175 

0.225 

2.15 

2.25 

0.40 

6.54 

0.125 

0.29 

2.48 

Th02. 


10 


0.26 


11 


1.27 


12 


6.30 


13 


14 


5.19     5.87 


15 


6.26 


16 


1.75 


17 


18 


1.93       3.40 


1.  Bennett's  Mill,  Silver  Creek,  Burke  Coun- 

ty. 

2.  Northeast    side    Brindle    Ridge,    Burke 

County. 

3.  White  Bank  gold  mine,  Burke  County. 

4.  Ball's  Creek,  at  Morganton  road   cross- 

ing, Burke  County. 

5.  Bailey's  Creek,  3  miles  southwest  of  Glen 

Alpine  Station,  Burke  County. 

6.  Linebacher    place,    Silver    Creek,  Burke 

County. 

7.  Mac  Lewrath  place,  Silver  Creek,  Burke 

County. 

8.  East    fork   of   Satterfield   Creek,   Burke 

County. 


9.  Mac  Lewrath  Branch,  McDowell  County. 

10.  Bracket- town,  South  Muddy  Creek,  Mc- 

Dowell County. 

11.  Long  Branch,  McDowell  County. 

12.  Alexander  Branch,  McDowell  County. 

13.  Daniel    Peeler's    farm   near   Bellwood, 

Cleveland  County. 

14.  Proctor's  farm,   near  Bellwood,  Cleve- 

land County. 

15.  Wade  McCurd's  farm,  Carpenter's  Knob, 

Cleveland  County. 

16.  Tailings  from  No.  15. 
Henrietta,  Rutherford  County. 


18.  Fallston,  Cleveland  County. 


METHOD  OF  ANALYSIS  OF  MONAZITE  SAND. 

The  method  of  analysis  employed  by  Dr.  Baskerville  is  given 
below  in  his  own  words1.  He  claims  only  "  approximate  results, 
and  absolute  accuracy  cannot  be  vouched  for."  It  is  substantially 
the  same  as  Prof.  S.  L.  Penfleld's  method2  with  a  few  modifica- 
tions. 

The  pulverized  sand,  2  grams,  is  weighed  into  a  small  flask 
holding  about  100  c.  c;  10  c.  c.  H2S04  (1  :1)  are  added,  and  the 
whole  cooked  on   a  sand   bath   with   frequent  agitation,  until  the 

rFrom  a  letter  to  the  writer,  March,  1895. 
2Am.  Jour.  Sci.  (3),  vol.  24,  1882,  p.  253. 


/ 


22  MONAZITE,    AND    MONAZITE    DEPOSITS 

acid  becomes  concentrated  and  fumes  arise.  A  small  funnel  is 
used  in  the  neck  of  the  flask  to  prevent  loss  by  spitting  and  bub- 
bling. It  is  allowed  to  cool,  and  if  not  completely  decomposed,  a 
fresh  amount  of  H2S04  is  added,  and  the  previous  operation 
repeated.  Add  a  little  water,  keeping  the  temperature  down  as 
well  as  possible.  The  insoluble  silicates  are  removed  by  filtering 
and  washing  with  cold  water.  The  clear  filtrate  is  diluted  to  400 
or  500  c.  c,  and  an  excess  of  oxalic  acid  added,  whereby  the 
oxalates  of  the  cerium  metals  and  thorium  are  precipitated. 
This  is  done  in  the  hot  solution,  allowing  the  same  to  boil  a  few 
moments  after  adding  the  oxalic  acid.  It  is  then  allowed  to 
remain  in  the  cold  for  twelve  hours,  when  it  is  filtered  and  washed 
with  cold  water. 

The  precipitated  oxalates  are  ignited  by  heating  slightly  above 
faint  redness.  After  all  the  carbon  is  burned  off,  the  contents  of 
the  crucible  are  turned  into  a  platinum  or  porcelain  dish,  washing 
the  crucible  with  H2S04  (1  :1).  On  heating,  the  oxides  are  usu- 
ally dissolved  completely;  the  excess  of  H2S04  is  gotten  rid  of  by 
gentle  heat.  To  accomplish  this,  the  disk  is  placed  on  a  triangle 
inside  of  an  iron  dish  to  which  the  lamp  flame  is  applied.  The 
sulphates,  which  are  almost  invariably  colored  red,  yellow  or 
orange,  are  dissolved  in  water.  The  whole  mass  is  usually  com- 
pletely soluble  in  about  15  c.  c.  H20,  but  on  further  dilution  a 
precipitate  is  formed.  The  solution  is  made  up  to  200  or  300  c.  c, 
i.  e.,  sufficient  water  is  added  to  hold  all  the  thorium  sulphate  in 
solution;  it  is  then  boiled  and  filtered.  If  the  filtrate  is  acid,  it 
is  neutralized  with  NH4OH,  and  the  thorium  is  precipitated  out 
by  means  of  Na2S203.  The  filtered  precipitate  is  burned  to  Th02 
and  weighed  as  such  in  a  platinum  crucible. 

CHEMICAL    AND    BLOWPIPE    REACTIONS. 

Monazite  is  with  difficulty  and  incompletely  soluble  in  hydro- 
chloric acid.  It  is  attacked  completely  by  sulphuric  acid,  and  by 
potassium  acid  sulphate.  It  is  infusible  before  the  blowpipe  flame, 
turning  gray.  When  moistend  with  H2S04  it  colors  the  flame 
bluish  green  (phosphorus  reaction).  The  borax  and  salt  of  phos- 
phorus beads   are  yellowish  when   hot,  and   colorless   on   cooling; 


IN    NORTH    CAROLINA.  23 

the  saturated  borax  bead  becomes  enamel  white  on  naming.  Fused 
with  soda,  the  mass  treated  with  water  and  filtered,  the  residue 
dissolved  in  a  little  HC1,  the  solution  gives  with  oxalic  acid  a  pre- 
cipitate, which  on  ignition  becomes  brick  red  (cerium  oxide). 
With  soda  on  charcoal  a  little  tin  is  sometimes  obtained. 

MICHRO-CHEMICAL 

For  cerium. — The  dilute  solutions  of  cerium  sulphate  or  chlo- 
ride give,  with  oxalic  acid  or  ammonium  oxalate,  a  precipitate, 
which  is  at  first  flocculent  but  soon  becomes  crystalline,  being 
composed  of  fine,  doubly  terminated,  often  forked  and  serrated 
prisms;  in  more  concentrated  solutions  these  form  themselves  into 
radial  groups.  The  little  crystals  have  an  oblique  extinction  and 
a  high  double  refraction.  In  hot,  very  dilute  solutions  thin 
rhomboidal  plates  are  precipitated,  whose  acute  angle  is  about  86°; 
they  have  a  tendency  to  form  rectangular  intergrowths,  and  appear 
to  be  monoclinic. 

For  phosphorus. — Phosphoric  acid  is  precipitated  in  a  solution 
of  the  sulphate  by  the  addition  of  ammonium  molybdate,  which 
on  drying  gives  little  crystals  resembling  rhombic  dodecahedrons, 
yellow  in  reflected  and  greenish  in  transmitted  light. 

Derby  2  has  found  that  these  micro-chemical  tests  are  the  best 
means  of  identifying  monazite. 

SPECTROSCOPIC    TESTS. 

Scharizer3  tested  the  absorption  spectrum  of  a  basal  cleavage 
plate  of  the  Shiittenhofen  monazite  by  replacing  the  ocular  of  the 
microscope  with  a  spectroscope  a  vision  direct e.  The  illumination 
was  obtained  by  the  reflection  of  direct  sunlight  from  a  concave 
mirror.  The  spectrum  showed  a  broad  absorption  band  in  the 
yellow  between  the  Fraunhofer  lines  C  and  D,  corresponding  to 
didymium,  and  a  less  broad  one  at  the  end  of  the  green  near  the 
line  F,  corresponding  to  erbium. 

1H.  Rosenbusch,  Mikroscopische  Physiograhie,  Vol.  T.,  3d  ed.,  1892,  p.  266. 

2Am.  Jour.  Sci.  3,  vol.  37, 1889,  pp.  109  114.    Zeitschr.  fur  Kryst.,  vol.  19, 1891,  p.  78. 

3Zeitscnr.  fiir  Kryst.,  vol.  12, 1887,  p.  264. 


24  MONAZITE,    AND    MONAZITE    DEPOSITS 


CHEMICAL    MOLECULAR    CONSTITUTION    OF    MONAZITE. 

Penneld,1  in  his  analyses  of  Connecticut,  North  Carolina,  and  Vir- 
ginia monazite  (see  anal.  Nos.  30,  31,  32,  33;  p.  20),  deduces  the 
relation 

(Ce,  La,  Di)  203:  P205=1  :  1 
Th02:  Si02    =1 :  1 

The  former  corresponds  to  the  normal  phosphate  of  the  cerium 
metals  (R2P203) ;  the  latter  corresponds  to  that  of  normal  thorium 
silicate,  which,  in  combination  with  a  small  percentage  of  water, 
makes  the  mineral  thorite  or  orangite  (ThSio^H20).  He  concludes, 
then,  that  monazite  is  essentially  a  normal  phosphate  of  the  cerium 
metals,  in  which  thorium  silicate  is  present  in  varying  proportions 
as  an  impurity  in  the  form  of  the  mineral  thorite  or  orangite. 

Dunnington2  had  somewhat  previously  come  to  the  same  conclu- 
sion. 

Rammelsberg's3  formula  of  thorium-free  monazite  from  Arendal, 
Norway,  was  R2P2Og=(Ce,  La,  Di)  2P208,  thus  agreeing  with  Pen- 
field. 

Blomstrand,4  from  his  analyses  of  Norwegian  and  Siberian  mona- 
zite (see  anal.  No.  1-10,  13-15,  pp.  17, 18),  concludes  that  the  mineral 
is  a  normal  tribasic  phosphate,  an  excess  of  bases  being  combined 
with  Si02.  Thus  :  m  (3RO,P205)+2EO,  Si02+pH20,  where  m=5 
to  20,  and  p=less  than  1  usually. 

He  does  not  believe,  as  Penneld  does,  that  the  thoria  is  origi- 
nally combined  with  silicia  as  thorite,  but  that  it  is  a  primary  con- 
stituent, present  as  the  phosphate,  either  in  combination  with  the 
cerium  or  as  an  isomorphous  mixture,  thus  : 

IV  III  ||  IY 

Ce.  Ce  (03PO)2  and  ETh  (03PO)2 ; 

and  that  it  is  altered  to  the  silicate  by  siliceous  waters. 

iAm.  Jour.  Sci.  (3),  vol.  24, 1882,  p.  250;  vol.  36, 1888,  p.  322.  Zeitschr.  fur  Kryst..  vol.  7, 1SS3. 
p.  366;  vol.  17,  1890,  p.  407. 

2Am.  Cuem.  Jour.,  vol.  4, 1882,  p.  138. 

3Zeitsclir.  Deutsch.  geol.,  Gesell.  Berlin,  vol.  29,  1877,  p.  79.  Zeitschr.  fur  Kryst.,  vol.  3. 
1879,  p.  101. 

^Zeitschr.  fur  Kryst.,  vol.  9, 1887,  p.  160;  vol.  20, 1892,  p.  367. 


IN    N0KTH    CAEOLINA. 


25 


Rammelsberg1  has  explained  the  analyses  of  Kersten   and  Her- 
mann (see  anal.  Nos.  19,  20,  p.  18),  respectively,  by  the  formulae : 
j  5  R3P2OM        ,  j  3K3F08) 
I  Th2  P2  O9    j   ana    (  Th3  P4  O10  j 

which  does  not,  however,  appear  to  express  a  constant  molecular 
constitution. 

ARTIFICIAL    PRODUCTION    OF    MONAZITE. 

In  1875  Radominsky2  produced  monazite  artificially  by  treat- 
ing a  solution  of  impure  cerium  salt  with  sodium  phosphate,  add- 
ing an  excess  of  chloride  of  cerium,  and  heating  to  redness.  After 
cooling  and  crystallization,  long  yellow  prisms  with  striated  sur- 
faces were  formed.  The  specific  gravity  was  5.09,  and  the  com- 
pound, by  analysis,  was  found  to  agree  in  composition  with  that 
of  the  mineral  monazite. 


GEOLOGICAL  AND  GEOGRAPHICAL  OCCURRENCE. 

The  following  table  presents  the  salient  features  of  the  geograph- 
ical, geological,  and  mineralogical  occurrences  of  monazite.  All 
known  localities  at  which  the  mineral  monazite  and  its  equiva- 
lents, turnerite,  cryptolite,  etc.,  have  been  found  up  to  the  present 
time  are  tabulated  here.  It  is  placed  at  the  beginning  of  this 
chapter  as  a  general  introduction,  and  for  the  purpose  of  conveni- 
ent reference,  to  what  is  to  follow. 

Conditions  of  occurrence  of  monazite. 


Localities. 

Country  Rocks. 

Associated  Minerals. 

UNITED  STATES. 

East  Blue  Fill,  Me 

Wakefield,  N   H  .. 

do 

Westerly,  R.  I    

do      

Westford,  Mass 

Gneiss 

do 

Xenotime. 

do 

Chester,  Conn 

do 

do 

Watertown,  Conn  

dnalbite)  Apatite, zircon, 

Portland,  Conn 

tourmaline. 

Yorktown,  N.  Y 

Sillimanite. 

Xenotime. 

Microlite,      araazouit  e, 

New  Speedway,  along  Harlem  river,  New- 
York  City 

beryl,    apatite,    orthite, 
columbite,      manganese 
tantalate. 

^andbuch  der  mineral.  Cliemie.  1875,  p.  305. 
2Comptes  Rendus,  vol.  80, 1875,  p.  305. 


26 


MONAZITE,    AND    MONAZITE    DEPOSITS 


Localities. 


Associated  Minerals. 


united  states.— Continued. 
Deake  mica  mine,  Mitchell  county,  N.  C. 


Ray  mica  mine,  Yancey  county,  N.  C. 

Mars  Hill,  Madison  county,  N.  C 

Boomer,  Wilkes  county,  N.  C 


Autunite,  uraninite,  gum- 
mite,  garnet. 

(In  orthoclase.)  Beryl, 
garnet. 

Quartz,  garnet,  zircon, 
rutile,  magnetite,  ilmen- 
ite. 

Rutile. 

In  quartz. 

Quartz,  garnet,  zircon, 
rutile,  brookite,  xeno- 
time,  f ergusonite.  corun- 
dum, epidote,  beryl,  cy- 
anite,  magnetite,  pyrite, 
menaccanite. 

Crowders  Mountain,  Gaston  county,  N.  C 

Todd's    Branch,    Mecklenburg     county,  Gold  placers I Garnet,  zircon,  diamond. . 

N.C 

Spartanburg  and  Greenville  counties,  S.  C 


Milholland's  Mill,  Alexander  county, 
N.  C 

Emerald  and  hid  denite  mine,  Alexander 
county,  N.  C 

Burke,  Rutherford,  Cleveland,  Polk,  Ca- 
tawba, and  Lincoln  counties,  N.  C 


"The  Glades,11  Hall  county,  Ga 

CANADA. 

Villeneuve  mica  mine,  Ottawa   county. 
Quebec 


SOUTH  AMERICA. 

Rio  Chico,  Antioquia,  United   States  of 

Columbia 

Alcobaca,  Province  of  Bahia,  Brazil 

Oaravellas,  Province  of  Bahia,  Brazil 

Salabro,  Province  of  Bahia,  Brazil 


Gneiss,  and   stream  (Same  as  Burke,  etc.  coun- 

placers ties,  N.  C.) 

Gold  placers Quartz,  rutile,  garnet,  etc. 


Pegmatite. 


Garnet,  tourmaline,  uran- 
inite. 


Province  of  Minas  Geraes. 


Province  of  Minas  Graes,  Rio  de  Janeiro 

and  Sao  Palo,  Brazil. 
Provinces  of  Bahia,  Minas  Geraes,  Rio  de  Porphyritic 


Gold  placers 

Beach  sands 

do  

Diamond  sands Quartz,  zircon,  garnet,  dls- 

j    thene,  staurolite.  corun- 
dum, 
do             Magnetite,    ilmenite.    py- 
rite. 
Gold  placers 


Janeiro,  and  Sao  Palo,  Brazil. 


Buenos  Ayres,  Argentine  Republic. 
Cordoba,  Argentine  Republic. 


Corn  wall - 


Holma 

Kararfvet 

Johannisberg. 


NORWAY. 


Dillingso,  Moss,  Lonnesby,  Arendal,  Nar 

estoe,  Hitteroe,  Hvalo 

Arendal  and  Midbo 

Notero 


Helle 


Ivalo 


FINNISH    LAPMARK. 


granu   Apatite,  magnetite,  imien- 


litic,  and  schistose 
gneisses,  red  syen- 
ite, granite  dikes...  I 

River  sands Zircon 

Gneiss  and  granite... 


ite,  rutile,  garnet,  zircon, 
Sillimanite. 


Clay  slates 


Albitic  granite. 
Cobalt  ore 


Pegmatite 
Granite 


Gold  sands. 


Quartz,  albite. 


Gadolinite,   hjelmite.  em- 
erald. 


Cryptolite  in  apatite. 
In  feldspar,  enveloped  by 
orthite. 


Zircon. 


1 


IN    NORTH    CAROLINA. 


27 


Localities. 

Country  Rocks. 

Associated  Minerals. 

RUSSIA. 

Albitic  granite 

Placers  

skite. 

BELGIUM. 

Nil  St.  Vincent 

FRANCE. 

Le  Puys,  near  St.  Christophe,  Dauphine... 

SWITZERLAND. 

sphene,  anatase. 

Quartz   vein,    tra- 
versing         mica 
schist. 

Rutile. 

Tessin 

Perdatsch 

Santa  Brigritta,  near  Ruaras,  Tavetsch 
Valley. 

GERMANY. 

Laacher  See,  near  Coblentz 

Druse    in    sanadine 
bomb. 

Pegmatite 

AUSTRIA. 

Josephinenhuette,  Riesengebirge,  Silesia 

(In  black  mica.)  Ilmenite, 
f  ergusonite,  yttrium 
spar,  zircon. 

Gadolinite,  yttrium -spar, 
xenotime,  f ergusonite. 

Apatite. 

In  beryl  and  feldspar. 

Schuttenhofen,  Bohemia  

Pegmatite 

Pisek,  Bohemia 

AUSTRALIA. 

Vegetable   Creek,   County   Gough,    New 
South  Wales. 

Monazite  is  an  accessory  constituent  of  the  granite  eruptives  and 
their  derived  gneisses.  It  has  been  found  in  these  rocks  over 
widely  separated  areas  of  the  earth's  surface,  and  further  search 
and  study  is  liable  to  reveal  its  probable  universal  presence,  in 
varying  proportions,  in  most  granites  and  granite  gneisses.  Thus 
Derby1  has  found  monazite  as  a  constant  accessory  constituent  in 
the  porphyritic,  granulitic,  and  schistose  gneisses  of  the  provinces 
of  Bahia,  Minas  Geraes,  Rio  de  Janeiro,  and  Sao  Palo,  in  Brazil, 
representing  300  miles  along  the  axis  of  the  great  gneiss  region  of 
the  Maritime  Mountains.  The  granite  dikes,  intersecting  the 
gneiss,  also  carry  monazite. 

The  gneisses  of  the  South  Mountain  region  in  North  Carolina, 
covering  an  area  of  some  2,000  square  miles,  in  Burke,  McDowell, 

!Am.  Jour.  Sci.,  vol.  37,  1889,  pp.  109-114. 


/ 


28  MONAZITE,    AND    MONAZITE    DEPOSITS 

Rutherford,  Cleveland,  Polk,  Catawba,  Lincoln,  and  Gaston  coun- 
ties, and  extending  into  Spartanburg  and  Greenville  counties,  S. 
C,  have  been  shown  to  contain  monazite.1  I  have  since  identified 
the  mineral  in  the  thin  sections  of  several  specimens  of  mica  gneiss 
collected  in  that  locality.  The  rocks  are  granitic  mica  gneisses, 
hornblende  gneisses,  which  approach  more  nearly  to  diorite  gneisses, 
and  pegmatites.     (See  map.     Plate  II.) 

Monazite  has  recently  been  found  in  Hall  county,  Georgia,  near 
"The  Glades,"  a  post-office  about  10  miles  northeast  of  Gainesville, 
on  the  north  side  of  the  Chattahoochee  river.  It  occurs  in  the 
gold  placers  of  Flat  creek  and  its  tributaries,  the  Glade,  Stocke- 
neter,  Hamilton  and  Huram  branches. 

Derby,2  by  examining  the  heavy  residues  of  a  number  of  hand 
specimens,  selected  at  random  from  the  collection  in  the  National 
Museum,  of  Washington,  D.  C,  described  the  occurrence  of  mon- 
azite in  certain  granites  and  gneisses  of  Maine,  New  Hampshire, 
Rhode  Island,  and  Massachusetts. 

The  monazite  of  Chester,  Portland,  and  Watertown,  Conn.,  is 
an  accessory  constituent  of  the  granite  and   gneisses.     In  Amelia 
county,  Ya.,  it  is  found  in  albitic  granite  ;  also  in  the  Ilmen  Moun 
tains  of  Russia. 

The  pegmatites  of  southern  Norway,  Silesia,  and  Bohemia,  and 
of  some  of  the  mica  mines  in  Canada  and  North  Carolina,  also 
contain  monazite. 

Derby  (in  paper  above  cited)  has  found  monazite  in  a  red  syenite 
at  Serra  do  Stauba,  in  the  province  of  Bahia,  Brazil.  The  basic 
eruptives  (diabase,  quartz-diorite,  mica-diorite,  and  minette)  thus 
far  examined  by  him  in  Brazil  showed  no  traces  of  monazite. 

The  turnerite  of  the  Laacher  See  (which  is  an  extinct  volcanic 
crater),  near  Coblentz,  in  Prussia,  was  found  in  a  druse  of  a  sana- 
dine  bomb,  the  only  known  occurrence  of  monazite  in  an  undoubted 
volcanic  rock.3     It  was  grown  into  and  upon  a  crystal  of  orthite. 

The  turnerite  of  Olivone,  Switzerland,  occurs  in  a  quartz  vein, 
20  to  30  cm.  thick,  traversing  crystalline  schists.4     The  percentage 

aTrans.  Am.  Inst.  Min.  Engr.,  Mar.,  1895. 

2Proc.  Rochester,  Acad.  Sci.,  vol.  1, 1891,  pp.  294-206. 

3G.  von  Rath.,  Poggendorff,  Annalen,  1871,  Erg.-Bd.,  5,  p.  413. 

*G.  Sellgman,  Zeitschr.  fur  Kryst.,  vol.  9, 1884,  p.  420. 


• 


I 


IN    NORTH    CAROLINA.  29 

of  monazite  in  these  rocks  is  exceedingly  small,  often  infinitesimal; 
thus  Derby  (in  paper  above  cited)  states  that  the  granite  dikes  in 
the  gneiss  of  Serra  de  Tingua,  near  Rio,  are  rich  in  the  yellow 
mineral,  carrying  0.02  to  0.03  per  cent,  and  a  fine-grained  granite 
dike  on  the  outskirts  of  Rio  de  Janeiro  showed  0.07  per  cent  mon- 
azite. 

The  cryptolite  of  Norway  occurs  as  inclusions  of  very  fine,  needle- 
shaped  crystals  in  apatite. 

While  making  a  reconnaisance  trip  through  the  North  Carolina 
region,  the  writer,  in  company  with  Messrs.  H.  A.  J.  Wilkens,  E. 
M.,  and  Jno.  R.  Kirksey,  discovered  on  June  19th,  1895,  the  inter- 
esting, and  so  far  as  known  new,  occurrence  of  monazite  in  cyanite. 
The  locality  where  first  observed  was  at  the  Peeler  and  Ivester 
placers  on  a  branch  of  Knob  creek,  about  16  miles  north  of  Shelby 
in  Cleveland  county,  N.  C.  Numerous  fragments  of  a  light  blue 
grey  cyanite,  usually  less  than  one  inch,  but  occasionally  as  large 
as  three  inches  in  longest  dimension,  were  found  in  the  tailing 
dumps  from  the  bottom  gravels  that  had  been  washed  in  the  sluice 
boxes.  The  fragments  of  pure  cyanite  contained  intimately  inter- 
grow  a  crystals  of  mcnazite,  the  latter  constituting  as  much  as  50 
per  cent  of  the  mass  at  times,  though  some  pieces  of  the  cyanite 
were  practically  barren.  The  bed  rock  and  out  cropping  ledges 
near  here  were  carefully  examined,  in  the  hope  of  finding  the  orig- 
inal source  of  this  monazite-bearing  cyanite,  but  without  success. 
It  probably  occurs  in  irregular  nests  and  veinlets  through  the  peg- 
matitic  mica  gneiss,  which  forms  the  country  rock. 

Derby  thinks  (in  paper  above  cited)  that  there  is  "a  reasonable 
probability  that  zircon,  and  to  a  less  degree  monazite,  may  prove 
to  be  guide  minerals  by  which  eruptives  and  their  derivatives  can 
be  certainly  identified,  no  matter  what  degree  of  alteration  they 
may  have  suffered." 

Monazite  has  not  been  found  in  the  sedimentary  rocks,  although 
it  may  be  present  in  some  of  these  as  a  secondary  mineral  of  trans- 
portation. 

The  economically  valuable  deposits  of  monazite  are  found  in  the 
placer  sands  of   streams  and   rivers,    and    in   the   irregular   sedi- 


30  MONAZITE,    AND    MONAZITE    DEPOSITS 

mentary  sand  deposits  of  old  stream  beds  and  bottoms.  Plates 
I.  and  III.  illustrate  the  occurrence  of  monazite  sands  along  the 
upper  reaches  of  a  small  branch.  The  decomposition  and  disintegra- 
tion of  the  crystalline  rocks,  the  original  source  of  the  mineral,  has 
proceeded  to  considerable  depths,  particularly  in  the  southern, 
unglaciated  countries.  By  erosion  and  secular  movement  the 
material  is  deposited  in  the  stream  beds  and  there  undergoes  a  nat- 
ural process  of  sorting  and  concentration,  the  heavy  minerals  being 
deposited  first  and  together.  The  richer  portions  of  these  stream 
deposits  are  thus  found  near  the  head  waters.  Such  deposits  have 
been  described  from  ISorth  and  South  Carolina  in  the  United  States, 
from  Brazil,  and  from  the  Sanarka  river  in  Russia. 

The  beach  sand  deposits  along  the  coast  of  Brazil,  in  the  province 
of  Bahia,  have  a  similar  explanation,  the  concentration  there  being 
brought  about  by  the  action  of  the  waves. 

ACCESSORY  MINERALS. 

The  main  constituent  of  the  granitic  rocks  (quartz,  feldspar,  and 
mica)  all  contain  the  monazite  as  intergrowths,  though  it  appears 
to  be  more  generally  confined  to  the  feldspar. 

Zircon  may  be  regarded  as  a  constant  associate;  in  fact,  it  is 
even  a  more  important  and  general  accessory  constituent  of  the 
rocks  than  monazite.  Among  the  other  usual  associated  minerals, 
of  coeval  origin  with  the  monazite,  are  xenotime,  fergusonite, 
sphene,  rutile,  brookite,  ilmenite,  cassiterite,  magnetite,  and  apa- 
tite;  sometimes  beryl,  tourmaline,  cyanite,  corundum,  columbite, 
samarskite,  uraninite,  gummite,  autunite,  gadolinite,  hjelmite,  and 
orthite. 

The  association  of  monazite  with  orthite,  gadolinite,  samarskite; 
uraninite,  and  hjelmite  is  interesting  as  suggesting  the  possibility 
of  some  genetic  relationship. 

Among  the  principal  secondary  and  metamorphic  minerals  found 
in  association  with  monazite  are  rutile,  brookite,  anatase,  epidote, 
orthite,  garnet,  sillimanite,  and  staurolite. 

ECONOMIC  USE. 

The  economic  value  of  monazite  lies  in  the  incandescent  proper- 


1 


£     o 


\ 


IN    NORTH    CAROLINA.  31 

ties  of  the  oxides  of  the  rare  earths — cerium,  lanthanum,  didymium- 
and  thorium — which  it  contains.  These  are  utilized,  principally 
the  thoria,  together  with  limited  quantities  of  the  lanthanum  and 
didymium,  in  the  manufacture  of  the  Welsbach  and  other  incan- 
descent gaslights.  The  cerium  goes  to  the  drug  trade  as  the  oxa- 
late. 

The  Welsbach  light  consists  of  a  cylindrical  hood  or  mantle  com- 
posed of  a  fibrous  network  of  the  rare  earths,  the  top  of  which  is 
drawn  together  and  held  by  a  loop  of  platinum  wire.  It  is  perma- 
nently suspended  over  the  flame  of  a  specially-devised  burner,  con- 
structed on  the  principles  of  the  Bunsen  burner,  in  which  the  gas 
is  burned  with  the  access  of  air,  thus  utilizing  the  heating  and  not 
the  illuminating  power  of  the  hydrocarbons.  The  mantle  becomes 
incandescent,  glowing  with  a  brilliant  and  uniform  light. 

The  method  of  manufacturing  this  mantle  is  in  brief  as  follows  : 
A  cylindrical  network,  about  1J  inches  in  diameter,  is  woven  out 
of  the  best  and  strongest  cotton  thread.  This  is  first  washed  in 
ammonia  and  then  in  warm  water,  being  wrung  out  in  a  mechani- 
cal clothes  wringer  each  time.  It  is  then  soaked  in  a  solution  of 
the  rare  earths  and  dried  in  a  revolving  hot-air  bath.  After  being 
cut  to  the  proper  lengths,  each  cylinder  is  shaped  over  a  wooden 
form,  and  the  upper  end  is  drawn  together  by  a  loop  of  platinum 
wire.  The  cotton  fiber  is  then  burned  off  under  the  flame  of  a 
Bunsen  lamp,  which  leaves  a  network  of  the  rare  oxides  exactly 
resembling  the  original  woven  cylinder,  each  fiber  being  identically 
preserved,  excepting  that  the  size  is  somewhat  reduced  by  shrink- 
age. After  a  series  of  tempering  and  testing  heats  of  various 
intensities  the  mantle  is  ready  for  use.  The  exact  composition  of 
the  solution  of  the  rare  earths  is  not  known,  being  one  of  the  trade 
secrets;  but  it  is  a  well  known  fact  that  monazite  rich  in  thoria  is 
sought  after,  and  the  natural  inference  is  that  this  element  consti- 
tutes one  of  the  most  important  ingredients. 

METHODS  OF  EXTRACTION  AND  CONCENTRATION. 

The  commercially  economical  deposits  of  monazite  are  those 
occurring  in  the  placer  sands  of  the  streams  and  adjoining  bottoms 
and  in  the    beach  sands    ah  ng  the    seashore.      The    geographical 


32  MONAZITE,    AND    MONAZITE    DEPOSITS 

areas  over  which  such  workable  deposits  have  been  found  up  to  the 
present  time  are  quite  limited  in  number  and  extent.  In  the 
United  States  the  placer  deposits  of  North  and  South  Carolina 
stand  alone.  This  area  includes  between  1600  and  2000  square 
miles,  situated  in  Burke,  McDowell,  Rutherford,  Cleveland,  and 
Polk  counties,  ]N\  C,  and  the  northern  part  of  Spartanburg  county, 
S.  C.  The  principal  deposits  of  this  region  are  found  along  the 
waters  of  Silver,  South  Muddy,  and  North  Muddy  creeks,  and 
Henrys  and  Jacobs  Forks  of  the  Catawba  river  in  McDowell  and 
Burke  counties  ;  the  Second  Broad  river  in  McDowell  and  Ruther- 
ford counties  ;  and  the  First  Broad  river  in  Rutherford  and  Cleve- 
land counties,  IS".  C,  and  Spartanburg  county,  S.  C.  These  streams 
have  their  sources  in  the  South  Mountains,  an  eastern  outlier  of  the 
Blue  Ridge.  The  country  rock  is  granitic  biotite  gneiss  and  dio- 
ritic  hornblende  gneiss,  intersected  nearly  at  right  angles  to  the 
schistosity  by  a  parallel  system  of  small  auriferous  quartz  veins, 
striking  about  N.  70°  E.,  and  dipping  steeply  to  the  N.W.  Most 
of  the  stream  deposits  of  this  region  have  been  worked  for  placer 
gold.  The  existence  of  monazite  in  commercial  quantities  here 
was  first  established  by  Mr.  W.  E.  Hidden,  in  1879.  The  thick- 
ness of  these  stream  gravel  deposits  is  from  1  to  2  feet,  and  the  width 
of  the  mountain  streams  in  which  they  occur  is  seldom  over  12  feet. 
The  percentage  of  monazite  in  the  original  sand  is  very  variable, 
from  an  infinitesimal  quantity  up  to  1  or  2  per  cent.  The  deposits 
are  naturally  richer  near  the  head  waters  of  the  streams. 

The  monazite  is  won  by  washing  the  sand  and  gravel  in  sluice 
boxes  exactly  after  the  manner  that  placer  gold  is  worked.  The 
sluice  boxes  are  about  8  feet  long  by  20  inches  wide  by  20  inches 
deep.  Two  men  work  at  a  box,  the  one  charging  the  gravel  on 
a  perforated  plate  fixed  in  the  upper  end  of  the  box,  the  other 
one  working  the  contents  up  and  down  with  a  gravel  fork  or 
perforated  shovel  in  order  to  float  off  the  lighter  sands.  These 
boxes  are  cleaned  out  at  the  end  of  the  day's  work,  the  washed 
and  concentrated  monazite  being  collected  and  dried.  Magne- 
tite, if  present,  is  eliminated  from  the  dried  sand  by  treatment  with 
a  large  hand  magnet.     Many  of  the  heavy  minerals,  such  as  zir- 


1 


/ 


^™^^"^^^^™ 


m 


j^jK. 


*,        "       \    ' 

»  ■■ 


i    s 


IN    NORTH    CAROLINA.  33 

con,  menaccanite,  rutile,  brookite,  corundum,  garnet,  etc.,  can 
not  be  completely  eliminated.  The  commercially  prepared  sand, 
therefore,  after  washing  thoroughly  and  treating  with  a  hand 
magnet,  is  notpure  monazite.  A  cleaned  sand  containing  from  65 
to  70  per  cent,  monazite  is  considered  of  good  quality.  From  20 
to  35  pounds  of  cleaned  monazite  sand  per  hand,  that  is,  from  40 
to  70  pounds  to  the  box,  is  considered  a  good  day's  work. 

But  very  few  regular  mining  operations  are  carried  on  in  the 
region.  As  a  rule  each  farmer  mines  his  own  monazite  deposit 
and  sells  the  product  to  local  buyers,  often  at  some  country  store 
in  exchange  for  merchandise. 

At  the  present  time  the  monazite  in  the  stream  beds  has  been 
practically  exhausted,  with  few  exceptions,  and  the  majority  of 
the  workings  are  in  the  gravel  deposits  of  the  adjoining  bottoms. 
These  deposits  are  mined  by  sinking  pits  about  8  feet  square  to 
the  bed  rock  and  raising  the  gravel  by  hand  labor  to  a  sluice  box 
at  the  mouth  of  the  pit.  The  overlay  is  thrown  away  excepting 
in  cases  where  it  contains  any  sandy  or  gritty  material.  The  pits 
are  carried  forward  in  parrallel  lines,  separated  by  narrow  belts 
of  tailing  dumps,  similar  to  the  methods  pursued  in  placer  gold 
mining.  At  the  Blanton  and  Lattimore  mines  on  Hickory 
creek,  2  miles  northeast  of  Shelby,  Cleveland  county,  N.  C,  the 
bottom  is  300  to  400  feet  wide,  and  has  been  partially  worked 
for  a  distance  of  one-fourth  of  a  mile  along  the  creek.  The 
overlay  is  from  3  to  4  feet,  and  the  gravel  bed  from  1  to  3  feet 
thick.     (See  Plate  IV.) 

The  methods  of  mining  and  cleaning  are  much  more  systematic 
in  Spartanburg  county,  S.  C,  than  in  the  North  Carolina  regions. 
Although  the  raw  material  contains  on  an  average  fully  as  much 
garnet,  rutile,  titanic  iron  ore,  etc.,  as  that  in  the  North  Caro- 
lina mines,  a  much  better  finished  product  is  obtained,  and  more 
economically,  by  making  several  grades.  Two  boxs  are  used  in 
washing  the  gravel,  one  below  the  other.  The  gravel  is  charged 
on  a  perforated  plate  at  the  head  of  the  upper  box,  and  the 
clean-up  from  this  box  is  so  thoroughly  washed  as  to  give  a  high 
grade  sand,  often  up  to  85  per  cent.  pure.      The  tailings  discharge 


■1 


34  MONAZITE,    AND    MONAZITE    DEPOSITS 

directly  into  the  lower  box,  where  they  are  rewashed,  giving  a 
second  grade  sand.  At  times  the  material  passes  through  as 
many  as  five  washing  treatments  in  the  sluice  boxes.  Even 
after  these  grades  are  obtained  as  clean  as  possible  by  washing, 
the  material,  after  being  thoroughly  dried,  is  further  cleaned  by 
pouring  from  a  cup,  or  a  small  spout  in  a  bin,  in  a  fine,  steady 
stream  from  a  height  of  about  4  feet,  on  a  level  platform  ;  the 
lighter  quartz  and  black  sand  with  the  fine-grained  monazite 
(tailings)  falls  on  the  periphery  of  the  conical  pile  and  is  con- 
stantly brushed  aside  with  hand  brushes ;  these  tailings  are 
aftewards  rewashed.  Instead  of  pouring  and  brushing,  the  mate- 
rial is  sometimes  treated  in  a  winnowing  machine  similar  to  that 
used  in  separating  chaff  from  wheat. 

Although  the  best  grade  of  sand  is  as  high  as  85  per  cent,  pure, 
its  quantitative  proportion  is  small  as  compared  with  the  second 
and  other  inferior  grades,  and  there  is  always  considerable  loss 
of  monazite  in  the  various  tailings.  It  is  impossible  to  conduct 
this  washing  process  without  loss  of  monazite,  and  equally  impos- 
sible to  make  a  perfect  separation  of  the  garnet,  rutile,  titanic 
iron  ore,  etc.,  even  in  the  best  grades.  The  additional  cost  of 
such  rewashing  and  rehandling  must  also  be  taken  into  consider- 
ation. 

If  the  material  washed  contains  gold,  the  same  will  be  col- 
lected with  the  monazite  in  concentrating.  It  may  frequently 
pay  to  separate  it,  which  can  easily  be  accomplished  by  treating 
the  whole  mass  over  again  in  a  riffle  box  with  quicksilver. 

It  has  been  shown  that  the  monazite  occurs  as  an  accessory 
constituent  of  the  country  rock,  and  that  the  latter  is  decomposed 
to  considerable  depths,  sometimes  as  much  as  100  feet.  On 
account  of  the  minute  percentage  of  monazite  in  the  mother  rock, 
it  is  usually  impracticable  to  economically  work  the  same  in 
place,  by  such  a  process  as  hydraulicking  and  sluicing,  for 
instance.  However,  even  hillside  mining  has  been  resorted  to. 
Such  is  the  case  at  the  Pheifer  mine,  in  Cleveland  county,  N.  C, 
2  miles  northeast  of  Shelby.  (See  Plate  V.)  The  country  rock 
is  a  coarse  mica  (muscovite  and  biotite)   gneiss,   and  the  small 


I  F 


IN    NORTH    CAROLINA. 


35 


monazite  crystals  may  at  times  be  distinctly  seen,  unaided  by  a 
magnifying  glass,  in  this  rock.  It  is  very  little  decomposed  and 
still  quite  hard,  and  the  material  that  is  mined  for  monazite  is 
the  overlying  soil  and  subsoil,  which  is  from  4  to  6  feet  thick. 
This  is  loaded  on  wheelbarrows  and  transported  to  the  sluice 
boxes  below  the  water  race.  The  yield  is  fairly  good,  and  the 
product  very  clean,  though  the  cost  of  working,  of  which,  unfor- 
tunately, figures  could  not  be  obtained,  must  be  considerably  in 
excess  of  that  of  bottom  mining.  Where  the  rock  contains 
sufficient  gold,  as  it  somtimes  does,  to  be  operated  as  a  gold 
mine,  there  is  no  reason  why  the  monazite  can  not  be  saved  as 
a  valuable  by-product. 

OUTPUT  AND  VALUE   OF  MONAZITE  IN  THE  UNITED  STATES. 

As  the  percentage  of  thoria  is  variable  in  different  sands,  the 
value  of  the  sand  consequently  varies  in  a  measure  also.  It  is 
stated  that  the  transparent  greenish  and  yellowish  brown  varie- 
ties are  often  rich  in  thoria,  but  this  can  not  be  depended  on. 

Hidden1  has  suggested  that  the  difference  in  cleavage  may  be 
an  indication  of  the  presence  or  absence  of  thoria,  that  crystals 
with  the  cleavage  best  developed  parallel  to  oo  Poo  are  the  pure 
phosphate  of  the  cerium  earths,  free  from  thoria,  while  those  in 
which  the  cleavage  is  best  developed  parallel  to  OP,  contain 
thoria.  But  the  cleavage  is  rarely  observable  in  the  rolled  grains, 
and  if  it  were  the  above  statement  is  by  no  means  a  proven  fact. 
He  also  makes  the  suggestion  (in  paper  above  cited)  that  the 
density  may'afford  a  test  of  the  approximate  comparative  amount 
of  thoria  present,  and  in  support  of  this  he  mentions  the  follow- 
ing examples  : 

Relation  of  thoria  contents  to  density  in  monazite. 


Specific 
gravity. 

Th02 

Localities. 

References. 

5  30 
5.20-5.25 

Per  cent. 
14. 23 

8.25 
6.49 

Amelia  Coui't-House,  Va 

Portland,  Conn  

Table,  p.  20,  anal.  No.  32. 
Table,  p.  20,  anal.  No.  30. 

5.10 

Burke  County,  N.  C  

Table,  p.  20,  anal.  No.  31. 

However,  this  will  scarcely  hold,  for  in   other  instances  mona- 
zite   of  the    specific    gravity   4.6-1    has  been  shown     to   contain 

*Am.  Jour.  Sci.,  vol.  32, 1886,  p.  207.    Zeitschr.  fur  Kryst.,  vol.  12, 1887,  p.  507. 


36 


MONAZITE,  AND    MONAZITE    DEPOSITS 


as  much  as  9.20  per  cent,  thoria  (from  Moss,  Norway  ;  see  p.  17. 
anal.  No.  4) ;  and  again,  monazite  of  the  specific  gravity  5.19 
contained  but  3.18  per  cent,  thoria  (from  Dillingso,  Norway :  see 
p.  17,  anal.  No.  2).  On  the  whole,  there  is  no  method  of 
determining  even  the  probable  percentage  of  thoria,  except- 
ing by  chemical  analysis.  Some  monazite  contains  practically 
no  thoria.  The  best  North  Carolina  sands  (highest  in  thoria; 
came  from  Burke  and  Cleveland  counties.  Some  of  the  highest 
grade  sand  from  Brindletown,  Burke  county,  runs  from  4  to  6.60 
per  cent,  thoria  ;  sand  from  Gum  Branch,  McDowell  county,  is 
reported  to  run  3.30  per  cent ;  sand  from  the  vicinity  of  Bell- 
wood  and  Carpenter's  Knob,  in  Cleveland  county,  runs  from  5 
to  6.30  per  cent.  The  fluctuation  of  the  thoria  percentage  is, 
however,  considerable  even  in  the  same  locality.  It  also  depends, 
of  course,  in  a  measure  on  the  degree  of  concentration  of  the 
sand. 

The  price  of  North  Carolina  monazite  has  varied  from  25  cents 
per  pound  in  1887  to  as  low  as  3  cents  for  inferior  grades  and  6 
to  10  cents  for  the  best  grades  in  1894  and  1895.  It  is  only  during 
the  past  two  years  that  the  mining  and  concentration  of  monazite 
sand  in  the  South  Mountain  region  has  grown  to  a  regular  indus- 
try, and  it  is  at  present  progressing  with  increased  vigor.  In 
1887  Mr.  Hidden  shipped  from  the  Brindletown  district,  in  Burke 
county,  N.  C,  12  tons  of  monazite  sand.  And  during  1888  and 
1889  a  number  of  tons  (exact  quantity  unknown)  were  shipped 
from  North  Carolina  to  the  Welsbach  Light  Company  in  Phil- 
adelphia. The  product  and  value  of  the  saud  during  1893  and 
1894  is  given  below.  It  was  shipped  in  part  to  the  AVelsbach 
Light  Company  and  in  part  to  Europe  (Germany  and  Austria). 
Product  and  value  of  monazite  in  1893  and  1894. 


1893. 

Value  at 

mines. 

1891. 

Value  at 

Quantity. 

Price. 

Quantity. 

Price. 

mines. 

Pounds. 
110,000 

Cents. 
6 
5 

$6,600 
1,600 

Pounds. 

460,000 

80,000 

6,855 

Cents. 

$31,050 

20,000 

4,800 

313 

130,000 

7,600 

546,855 

36,193 

1 


IN    NORTH    CAROLINA.  37 

In  Brazil  considerable  deposits  of  monazite  occur  in  the  beach 
sands  along  the  seashore.  The  largest  of  these  is  found  in  the 
extreme  southern  part  of  the  Province  of  Bahia,  near  the  island 
of  Alcobaca.  The  surf  as  it  breaks  against  the  cliffs  washes 
away  the  lighter  earths  and  minerals,  leaving  naturally  concen- 
trated deposits  of  monazite  along  the  beach.  Sacks  filled  with 
this  sand  were  shipped  to  New  York  in  1885,  the  deposit  having 
been  taken  for  tin  ore.  Its  true  character  was,  however,  soon 
recognized,  and  since  then  a  number  of  tons  have  been  shipped 
in  the  natural  state,  without  any  further  concentration  or  treat- 
ment, as  ballast,  mainly  to  the  European  markets.  It  is  reported 
to  contain  3  to  I  per  cent  thoria.  Very  little  exact  information 
concerning  these  Brazilian  deposits  is  at  present  available.  Mona- 
zite has  also  been  found  in  the  gold  and  diamond  placers  of  the 
Provinces  of  Bahia  (Salabro  and  Caravellas),  Minas  Geraes  (Dia- 
mantia),  Bio  de  Janeiro  and  Sao  Paulo.  It  has  been  found  in  the 
river  sands  of  Buenos  Ayres,  Argentine  Republic,  and  also  in  the 
gold  placers  of  Bio  Chico,  at  Antioquia,  in  the  United  States  of 
of  Colombia. 

In  the  Ural  Mountains  of  Bussia  monazite  is  found  in  the 
Bakakui  placers  of  the  Sanarka  Biver.  The  placer  gold  mines 
of  Siberia  are  reported  to  contain  monazite. 

Economic  deposits  of  monazite  are  also  reported  to  exist  in  the 
pegmatite  dikes  of  Southern  Norway.  It  is  picked  by  the  miners 
while  sorting  feldspar  at  the  mines.  It  is  not  known  to  exist  in 
placer  deposits.  The  annual  output  is  stated  to  be  not  more  than 
one  ton,  which  is  shipped  mainly  to  Germany.1 

!U.  S.  Consular  Report ;  vol.  48,  No.  179,  Aug.  1895,  p.  550. 


/ 


38  MONAZITE,    AND    MONAZITE    DEPOSITS 

BIBLIOGRAPHY. 

Bauer  (Max).     Lehrbuch  der  Mineralogie,  Berlin  u.  Leipzig,  1886,  p.  495. 

Becquerel  (H.)  Absorptions-Spectra  der  Krystalle  :  Zeitschr.  Mr  Kryst, 
vol.  18,  1891,  p.  332 ;  Ann.  Chem.  Phys.  (6),  vol.  14,  p.  170. 

Blomstrand  (C.  W.)«  Analysen  von  Monazit  u.  Xenotim :  Geol.  For. 
Forh.,  vol.  9,  1887,  p.  160;  Zeitschr.  fur  Kryst,  vol.  15,  1889,  p.  99. 

Ueber  einige  schwedische  Monazite  :  Geol.  For.  Forh.,  vol.  11,  1889,  p. 

171 ;  Zeitschr.  fur  Kryst.,  vol.  19,  1891,  p.  109. 

Ueber  den  Monazit  vom  Ural :    Lunds  Universitets  Arskrift,    vol.    24, 

1888;  Zeitschr.  fur  Kryst.,  vol.  20,  1892,  p.  367. 

Breithaupt  (Aug.).  Ueber  den  Monazit,  eine  neue  Species  des  Mineral- 
Reichs:Schweigger-Seidel,  vol.  55,  1829,  p.  301. 

Brooke  (H.  J.).  Ueber  den  Monazit,  eine  neue  Mineral-Species,  etc.  : 
Poggendorff,  Annalen,  vol.  23,  1831,  p.  362 ;  Philosophical  Magazine 
and  Annals,  vol.  10,  p.  187. 

Brush  (G.  J.).  Manual  of  Determinative  Mineralogy,  New  York,  1875, 
p.  93. 

Dafert  (E.  W.)  and  Derby  (O.  A.).  On  the  Separation  of  Minerals  of 
High  Specific  Gravity :  Proc.  Rochester  Acad.  Sci.,  vol.  2,  Jan., 
1893,  pp.  122-132. 

Dahll  (T.)  and  Forbes  (D.).  Urdite  :  Am.  Jour.  Sci.  (2),  vol.  22,  1856,  p. 
262 ;  Nyt.  Mag.  for  Naturvidenskaberne,  vol.  8,  1855,  p.  227. 

Damour  (A.).     Analysis  :    Ann.  Chem.  Phys.  (3),  vol.  51,  p.  445. 

Dana  (E.  S.).  Text-Book  of  Mineralogy,  1883,  pp.  364  (cryptolite) ;  368,  432 
(monazite,  etc.). 

On  Crystals  of  Monazite  from  Alexander  Co.,  N.  C.  :  Am.  Jour.  Sci.  (3), 

vol.  24,  1882,  p.  247  et  seq.  ;  Zeitschr.  fur  Kryst.,  vol.   7,   1883,  pp. 
362-366. 

Dana  (J.  D.).  Crystallographic  Examination  of  Eremite  :  Am.  Jour.  Sci. 
(1),  vol.  33,  1838,  p.  70. 

Monazite  :  Am.  Jour.  Sci.  (2),  vol.  25,  1858,  p.  410 ;  vol.  34,  1862,  p.  217. 

Note  on  Possible  Identity  of  Turnerite  and  Monazite ;  Am.  Jour.  Sci. 

(2),  vol.  42,  1866,  p.  420. 

System  of  Mineralogy,  6th  ed.,  1892,  pp.  749-753. 

Manual  of  Geology,  4th  ed.,  1895,  p.  85. 

Derby  (O.  A.).  On  the  Occurrence  of  Monazite  as  an  Accessory  Element 
in  Rocks  :  Am.  Jour.  Sci.  (3),  vol.  37,  1889,  pp.  109-114 ;  Zeitschr.  fur 
Kryst.,  vol.  19,  1891,  p.  78. 

On  the  Separation  and  Study  of  the  Heavy  Accessories  of  Rocks  :  Proc. 

Rochester  Acad.  Sci.,  vol.  1,  1891,  pp.  198-207. 


IN    NORTH    CAROLINA.  39 

AND  Dafert  (E.  W.).     On  the  Separation  of  Minerals  of  High  Specific 

Gravity:  Proc.  Rochester  Acad.  Sci.,  vol.  2,  Jan.,  1893,  pp.  122-132. 

Des  Cloizeaux  (A.),  Annales  des  Mines,  1842  (4),  vol.  2,  p.  362;  Ann. 
Chem.  Phys.,  1857,  (3),  vol.  51,  p.  446. 

Manuel  de  mineralogie,  Paris,  1862,  vol.  1,  p.  533;  Paris,  1874,  vol.  2, 

XLV. 

Des  Cloizeaux  (A.)  and  Pisani  (F.).  Turnerit  von  Luzerne :  Zeitschr. 
deutsch.  geol.  Gesell.,  Berlin,  vol.  25,  1873,  p.  568. 

— ; Note  sur  la  Roscoelite    *    *    *     et  la  Monazite  :  Bull.  Soc.  Mill., 

1881,  vol.  4,  p.  56 ;  Zeitschr.  fur  Kryst,,  vol.  6.  1882,  p.  229. 

Dufrenoy  (A.).  Traite'  de  Mineralogie  :  vol.  2,  1856,  pp.  504-509  ;  vol.  4, 
1859,  p.  683. 

Dunninoton  (F.  P.).  Columbite,  Orthite,  and  Monazite  from  Amelia 
County,  Va.  :  Am.  Jour.  Sci.  (3),  vol.  24,  1882,  p.  153;  Amer.  Chem. 
Jour.,  1882,  vol.  4,  p.  138;  Zeitschr.  fur  Kryst.,  vol.  7,  1883,  p.  423. 

Fiedler  (K.  G.).  Lagerstaten  des  Diaspor  *  *  *  u.  Monazit :  Poggen- 
dorff,  Annalen,  vol.  25,  1832,  p.  332, 

Fischer  (H.).  Mikroskopisch-Mineralogische  Miscellen :  Zeitschr.  fiir 
Kryst.,  vol.  4,  1880,  p.  373. 

Fontaine  (W.  F.).  Notes  of  Minerals  in  Amelia  County,  Va.:  Am.  Jour. 
Sci.  (3),  vol.  25,  1882,  p.  337. 

Forbes  (P..)  and  Dahll  (T.).  Urdite  :  Am.  Jour.  Sci.  (2),  vol.  22,  1856,  p. 
262 ;  Nyt  Mag.  for  Naturvidenskaberne,  vol.  8,  1855,  p.  227. 

Fouque  (F.)  and  Levy  (A.  Michel.)  Synthase  des  Mineraux  et  des  Roches, 
Paris,  1882,  p.  253. 

Franck  (A.).  Krystallographische  Untersuchungen  des  Monazits  von  Nil- 
Saint- Vincent  :  Zeitschr.  fiir  Kryst.,  vol.  23,  1894,  p.  476 ;  Bull.  Acad, 
roy.  Belgique,  1891  (3),  vol.  21,  p.  40. 

Genth  (F.  A.).  Contributions  to  Mineralogy  :  Am.  Jour.  Sci.  (2),  vol.  33, 
1862,  p.  204 ;  (3),  vol.  38,  1889,  p.  203  ;  (3),  vol.  40,  1890,  p.  116  ;  Zeitschr. 
fiir  Kryst,,  vol.  19,  1891,  p.  88. 

The  Minerals  of  North  Carolina :  Bull.  U.  S.  Geol.  Survey  No.  74,  1891, 

pp.  77-78. 

Goldschmidt  (V.).  Index  der  Krystallformen  der  Mineralien,  vol.  2,  1890, 
pp.  399-401 ;  Zeitschr.  fiir  Kryst.,  vol.  10,  1885,  p.  261. 

Gorceix  (M.  H.).  Die  Mineralien  der  Diamantlagerstatten  von  Salabro, 
Prov.  Bahia:  Zeitschr.  fiir  Kryst,,  vol.  12,  1886,  p.  639;  Compt. 
Rend.,  1884,  vol.  98,  p.  1446;  Bull.  Soc.  Min.,  1884,  vol.  7,  p.  209. 

Monazit  von  Caravellos,  Brasilien  :  Zeitschr.  fiir  Kryst,,  vol.  12,  1887,  p. 

643;  Compt.  Rend.,  1885,  vol.  100,  p.  356;  Bull.  Soc.  Min.,  1885,  vol. 
8,  p.  32. 


40  MONAZITE,    AND    MONAZITE    DEPOSITS 

Groth  (P.).  Die  Minerallagerstatten  des  Dauphine  :  Zeitschr.  fiir  Kyrst., 
vol.  13,  1888,  p.  96;  Sitzungsber,  bayer.  Akad.  Wiss.,  1885,  pp.  371- 
402. 

Tabellarische   Uebersicht   der  Mineralien,  3d  ed.,   1889,  p.   72;    Jour. 

prakt.  Chemie,  vol.  33,  p.  90. 

Hermann  (R.).  Untersuchungen  uber  Zusanimensetzung  des  Monazits  in 
Beziehung  auf  den  angeblichen  Thonerde-Grehalt  (Monazitoid) : 
Jour,  prakt.  Chemie,  vol.  40,  1847,  p.  21 ;  vol.  93,  p.  109  ;  Am.  Jour. 
Sci.  (2),  vol.  8,  p.  125. 

Heteromeres  Krystall-System,  1860,  p.  196. 

Hessenberg  (Fr.).     Turnerit :  Neues  Jahrbuch,  1874,  p.  826. 

Hidden  (W.  E.).  Notice  on  Occurrence  of  Monazite  :  Am.  Jour.  Sci.  (3), 
vol.  21,  1881,  p.  159. 

Notes  of  Mineral  Localities  :  Am.   Jour.   Sci.   (3),  vol.  22,  1881/  p.  21 : 

Zeitschr.  fiir  Kryst.,  vol.  6,  1882,  p.  517. 

Contributions  to  Mineralogy  :  Am.  Jour.  Sci.  (3),  vol.  32,  1886,  p.  207  : 

Zeitschr.  fiir  Kryst.,  vol.  12,  1887,  p.  507. 

Hoffman  (G.  C).  Uraninite  and  Monazite  from  Canada  :  Am.  Jour.  Sci. 
(3),  vol.  34,  1887,  p.  73;  Zeitschr.  fiir  Kryst.,  vol.  15,  1889,  p.  127. 

Hussak  (E.),  Mineralogische  Notizen  aus  Brasilien  :  Zeitschr.  fiir  Kryst.. 
vol.  24,  1895,  p.  430. 

Jeremejew  (P.  v.).  Monazit-Krystalle  aus  dem  Ilmengebirge  :  Zeitschr. 
fiir  Kryst.,  vol.  1,  1877,  p.  398. 

Kersten  (C).  Untersuchung  des  Monazits:  Poggendorff,  Annalen.  vol. 
47,  1839,  p.  385. 

Koenio  (Gr.  A.).  Notes  on  Monazite  :  Proc.  Acad.  Nat.  Sci.  Philadelphia. 
Jan.  24,  1882,  p.  15;  Zeitschr.  fiir  Kryst,,  vol.  7,  1883,  p.  423. 

Koksharow  (N.  v.).  Materialien  zur  Mineralogie  Russlands,  vol.  4,  1862. 
pp.  7-34;  vol.  6,  1870,  pp.. 200  and  387;  vol.  9,  1884,  p.  10;  vol.  10. 
1884,  p.  155. 

Levy  (A.  Michel).  Description  of  a  New  Mineral  ;  Ann.  of  Phil.,  London, 
1823,  vol.  5,  p.  241. 

Description  d'une  Collection  des  Mineraux,  Paris,  1837,  vol.  3,  p.  423. 

et  Fouque  (F.).     Synthase  des  Mineraux  et  des  Roches,  Paris,  1882, 

p.  253. 
et  Lacroix  (Alf.).     Les  Mineraux  des  Roches,  Paris,  1888,  p.  242. 

Liverside  (A.).  The  Minerals  of  New  South  Wales,  Sydney,  2d  ed.,  1882, 
p.  137  ;  Zeitschr.  fiir  Kryst.,  vol.  8,  1884,  p.  87. 

Mallard  (M.  Er.).  Sur  la  Cryptolite  de  Norvege  :  Bull.  Soc.  Min.,  1887, 
vol.  10,  p.  236. 


1 


IN    NORTH    CAROLINA.  41 

Miers  (H.  A.).  Ueber  Connellit  und  Monazit  von  Cornwall  :  Min.  Mag.  & 
Jour.  Min.  Soc.  London,  No.  30,  Aug.,  1885,  vol.  6,  p.  164;  Zeitschr. 
fiir  Kryst.,  vol.  12,  1887,  p.  181. 

Fundort  des  Turnerit  :  Min.  Mag.  &  Jour.  Min.  Soc.  London,  No.  39, 

1889,  vol.  8,  p.  200  ;  Zeitschr.  fur  Kryst.,  vol.  19,  1891,  p.  415. 

Naumann  (C.  F.)  and  Zirkel  (F.).  Eelemente  der  Mineralogie,  Leipzig, 
1885,  p.  514  (cryptolite) ;  p.  515  (monazite). 

Nitze  (H.  B.  C).  North  Carolina  Monazite  :  Trans.  Am.  Inst.  Min.  Engr., 
Florida  meeting,  March,  1895. 

Penfield  (S.  L.).  On  the  Occurrence  and  Composition  of  Some  American 
Varieties  of  Monazite :  Am.  Jour.  Sci.  (3),  vol.  24,  1882,  p.  250 ; 
Zeitschr.  fiir  Kryst.,  vol.  7,  1883,  pp.  336-371. 

and  Sperry.     Mineralogical  Notes  :  Am.  Jour.  Sci.  (3),  vol.  36,  1888,  p. 

322;  Zeitschr.  fiir  Kyrst.,  vol.  17,  1890,  p.  407. 

Pisani  (F.)  and  Des  Cloizeaux  (A.).  Turnerite  von  Luzerne  :  Zeitschr. 
deutsch.  geol.  Gesell.,  Berlin,  vol.  25,  1873,  p.  568. 

Chemische  Untersuchung  des    Turnerit :   Zeitschr.  fiir  Kryst.,  vol.  1, 

1877,  p.  405  ;  Compt.  Rend.,  vol.  84,  p.  462. 

Phillips  (Wm.).  Elementary  treatise  on  Mineralogy,  5th  American  ed., 
Boston,  1844,  p.  138  (turnerite) ;  p.  422  (monazite). 

Mineralogy,  edited  by  H.  J.  Brooke  and  W.  H.  Miller,  London,  1852,  p. 

493  (monazite) ;  p.  494  (cryptolite) ;  p.  653  (turnerite) ;  p.  678  (mon- 
azitoid). 

Quenstedt  (Fr.  A.).     Handbuch  der  Mineralogie,  Tiibingen,  1877,  p.  585. 

Radominsky  (F.).  Sur  un  Phosphate  de  Cerium  renfermant  du  Fluor: 
Compt.  Rend.,  vol.  78,  1874,  p.  764. 

Reproduction  artificielle  de  la  Monazite,  et  de  la  Xenotime  :  Compt. 

Rend.,  vol.  80,  1875,  p.  304. 

Rammelsbero  (C.  F.).  Handbuch  der  Mineral-Chemie,  Leipzig,  1875,  2d 
ed.,  pp.  304-305. 

Erganzungs-Heft  to  2d  edition,  Leipzig,  1886,  pp.  168,  169. 

Ueber  Nephelin,  Monacit,  etc.:  Zeitschr.  deutsch.  geol.  Gessell.,  Berlin, 

vol.  29,  1877,  p.  79  ;  Zeitschr.  fiir  Kryst.,  vol.  3,  1879,  p.  101. 

Renard  (A.).  Monazit  von  Nil  St.  Vincent:  Zeitschr.  fiir  Kryst.,  vol.  6, 
1882,  p.  544. 

Rice  (W.  N.).  Minerals  from  Middletown,  Conn.:  Am.  Jour.  Sci.  (3),  vol. 
29,  1885,  p.  263  ;  Zeitschr.  fiir  Kryst,,  vol.  2,  1886,  p.  300. 

Richter  (Th.).  Plattner's  Manual  of  Qualitative  and  Quantitative  Anal- 
ysis with  the  Blowpipe  (transl.  by  H.  B.  Cornwall),  4th  ed.,  New 
York,  1880,  pp.  200-203. 


/ 


42  MONAZITE,    AND    MONAZITE    DEPOSITS 

Rose  (G.).     Reise  nach  dem  Ural  und  Altai,  Berlin,  1842,  vol.  2,  pp.  87  and 

482. 

Rose  (GL).  Ueber  die  Identitat  des  Edwardsit  u.  Monazit :  Poggendorff. 
Annalen,  vol.  49,  1840,  p.  223. 

Rosenbusch  (H.).  Mikroscopische  Petrographie  der  petrographisch  wich- 
tigen  Mineralien,  3d  ed.,  1892,  pp.  266  (cerium)  and  498. 

Seligmann  (G.).  Mineralogische  Notizen  :  Zeitschr.  fur  Kryst.,  vol.  6, 
1882,  p.  231 ;  Verhandl.  d.  naturh.  Ver.  Bonn,  1880,  vol.  37,  pp.  130, 
131. 

Mineralogische  Beobachtungen  :  Zeitschr.  Mr  Kryst.,  vol.  9,  1884,  p.  420. 

Schartzer  (R.).  Der  Monazit  von  Schiittenhofen  :  Zeitschr.  Mr  Kryst. 
vol.  12,  1887,  p.  255. 

Shepard  (C.  U.).  Treatise  on  Mineralogy,  1st  ed.,  vol.  2,  1835,  p.  53;  2d  ed" 
1844. 

Description  of  Edwardsite,  a  new  mineral :  Am.  Jour.  Sci.  (1),  vol.  32, 

1837,  p.  162;  Poggendorff,  Annalen,  vol.  43,  1838,  p.  148. 

Notice  of  Eremite,  a  new  mineral  species  :  Am.  Jour.  Sci.  (1),  vol.  32, 

1837,  p.  341. 

Sperry  (F.  L.)  and  Penfield.  Mineralogical  Notes  :  Am.  Jour.  Sci.  (3), 
vol.  36,  1888,  p.  322;  Zeitsch.  Mr  Kryst.,  vol.  17,  1890,  p.  407. 

Trechmann  (C.  O.).  Beitrage  zur  Kennthniss  des  Turnerit :  Neues  Jahr. 
buch,  1876,  p.  593. 

Tschermak  (G\).     Lehrbuch  der  Mineralogie,  Vienna,  1888,  p.  535. 

U.  S.  Consular  Report,  vol.  48,  No.  176,  May,  1895,  p.  170.  Uses  of  Monazite 
in  Europe. 

vol.  48,  No.  179,  Aug.,  1895,  pp.  541-551.     Monazite  in  Foreign  Countries. 

Vom  Rath  (G.).  Mineralogische  Mittheilungen  :  Poggendorff,  Annalen, 
vol.  119,  1863,  p.  247;  vol.  122,  1864,  p.  407. 

Uber  ein  neues  Vorkommen  von  Monazit  (Turnerit)  vom  Laachersee  : 

Sitzungsber.  bayer.  Akad.  Wiss.,  1870,  vol.   2,  p.  271;  Poggendoff, 
Annalen,  Erg.  Bd.  5,  1871,  p.  413. 

Notes  on  the  Mineralogy  of  North  Carolina  :  Am.  Jour.  Sci.  (3),  vol.  33, 

1887,  p.  160. 

Ueber  Beryll,  Monazit,  etc.,  von  Alexander  County,  N.  C.  :  Zeitschr. 

Mr   Kryst.,  vol.  13,    1888,  p.  596;  Sitzungsber.  nied.  Ges.  Bonn,  1866, 
pp.  67,  68,  149,  254. 

Watts  (H.).  On  Phosphocerite,  a  new  mineral  containing  phosphate  of 
cerium  :  Quart.  Jour.  Chem.  Soc,  London,  1850,  vol.  2,  p.  131. 

Websky.  Monazit  von  Schreiberhau :  Zeitschr.  deutsch.  geol.  Gesell.. 
Berlin,  vol.  17,  1865,  p.  567. 


1 


IN    NORTH    CAROLINA.  43 

Wohier  {¥.).     Ueber  den  Kryptolith  :  Poggendorff  Annalen,  vol.  67,  1846, 
p.  424. 

Zirkel  (F.)  and  Naumann  (C.  F.).     Elemente  der  Mineralogie,  Leipzig, 
1885,  p.  514  (kryptolith);  p.  515  (monazit). 

Lehrbuch  der  Petrographie,  1893,  vol.  1,  p.  432. 

Zschau  (E.).     Fifth  Supplement  to  Dana's  Mineralogy,  Am.  Jour.  Sci.  (2) 
vol.  25,  1858,  p.  410. 


/ 


INDEX. 

Page. 

Analyses  of  monazite 17-20 

Analysis,  method  of 21,  22 

Angular  measurements  of  monazite 13 

Argentine  Republic,  monazite  in 26,  37 

Artificial  production  of  monazite 25 

Associated  minerals  of  monazite 25-27,  30 

Australia,  monazite  in 27 

Austria,  monazite  in 27 

Axial  ratios  of  monazite 12 

Baskerville,  C,  cited 21 

Belgium,  monazite  in 27 

Bibliography 38-43 

Blanton  mine,  N.  C 33 

Blomstrand,  C.  W.,  cited 10,  16,  17,  18,  24 

Blowpipe  reactions  of  monazite 22-23 

Brazil,  monazite  in 26,  27,  30,  37 

Breithaupt,  A.,  cited 8,14,  15 

Brooke,  H.  J.,  cited 9 

Burke  county,  N.  C,  monazite  in 21,  26,  27,  32,  36 

Canada,  monazite  in 26 

Chemical  composition  of  monazite 7,  14-21 

Chemical  molecular  constitution  of  monazite 24,  25 

Chemical  reactions  of  monazite 22,  23 

Children,  cited 14 

Cleveland  county,  N.  C,  monazite  in 21,  26,  28,  29,  32,  33,  34,  36 

Concentration  of  monazite 32-35 

Country  rocks,  monazite  region 25-27,  28,  29 

Cryptolite 7,  9,  11,  15,  29 

"  crystal  form  of 11 

"  identity  with  monazite 9 

Crystal  form  of  cryptolite 11 

Crystal  form  of  monazite 10,  11,  12 

Cyanite,  monazite  in 29 

Dahll,  T.,  cited ". 10 

Damour,  A.,  cited 19 

Dana,  E.  D.,  cited 12 

Dana,  J.  D.,  cited 8,  9,  10,  12 

Derby,  O.  A.,   cited 12,  28,  29 

Des  Cloizeaux,  A.,  cited 8,  10,  13,  14 

Dunnington,  F.  P.,  cited 20,  24 

Economic  use  of  monazite 30-31 


INDEX.  45 


Page. 

Edwardsite 7,  9,  14 

"  identity  with  monazite 9 

England,  monazite  in 26 

Eremite 7,  9 

"        identity  with  monazite 9 

Fiedler,  K.  G.,  cited 8 

Finnish  Lapmark,  monazite  in 26 

Forbes,  D.,  cited 10 

France,  monazite  in 27 

Franck,  A.,  cited 12 

Genth,  F.  A.,  cited 16,  20 

Geological  and  geographical  occurrence  of  monazite 25-30,  32 

Georgia,  monazite  in 26,  28 

Germany,  monazite  in 27 

Gorceix,  M.  H.,  cited 19 

Hermann,  R.,  cited 9,  15,  18,  25 

Hidden,  W.  E.,  cited 32,  35 

Historical  sketch  of  monazite 7-10 

Incandescent  gas  lights 31 

Ivester  mine,  N".  C .- 29 

Kararfveite 10,  16 

"  identity  with  monazite 16 

Kersten,  C,  cited 15,  18,  25 

Kokscharow,  N.  V.,  cited 9,  10,  12,  15 

Konig,  G.  A.,  cited 20 

Lattimore  mine,  N.  C 33 

Levy,  A.,  cited 7 

Liversidge,  A.,  cited 19 

Localities  of  monazite 25-27 

Mallard,  M.  E.,  cited 9 

McDowell  county,  3ST.  C,  monazite  in 21,  26,  27,  32,  36 

Menge,  cited 8 

Mengite 7,  9 

Methods  of  extraction  and  concentration  of  monazite 31-35 

Micro-chemical  reactions  of  monazite 23 

Miers,  H.  A.,  cited 11 

Monazite, 

Analyses  of 17-20 

Artificial  production  of... 25 

Associated  minerals  of 25-27,  30 

Blowpipe  reactions  of 22,  23 

Brief  description  of 7 

Chemical  composition  of 7,  14-25 

Chemical  molecular  constitution  of 24,  25 

Chemical  reactions  of 22,  23 

Country  rocks  of 25-27,  28,  29 


46  INDEX. 


Monazite— Continued.  Page. 

Crystallization  of 10,  11,  12 

Derivation  of  name 9 

Earliest  recognition  of 8 

Economic  use  of 30,  31 

Extraction  and  concentration  of 31-35 

Geological  and  geographical  occurrence  of 25-30.  32 

Historical  sketch  of 7-10 

Localities   of 25-27 

Microscopic  distinctions  of 13 

Method  of  analysis  of 21,  22 

Method  of  formation   in  beds 30 

Micro-chemical  reactions  of 23 

Nomenclature  of 7-10 

Optical  properties  of 13,  14 

Output  and  value  of  in  United  States 35-37 

Percentage  of  in  sand 32,  33,  34 

Percentage  of  in  rocks 29 

Physical  properties  of 7,  12,  13 

Price  of  in  North  Carolina 36 

Spectroscopic  tests  of 23.  24 

Use  of 30,  31 

Variation  of  thoria  in 35,  36 

Monazitoid 7,  9,  15 

"  color  of 13,  15 

Nomenclature  of  monazite 7-10 

North  Carolina  monazite  region , 26,  27,  30,  32 

Norway,  monazite  in 26,  37 

Occurrence  of  monazite,  geological  and  geographical 25  30,  32 

Optical  measurements  of  monazite 13,  14 

Output  and  value  of  monazite  in  United  States 35  37 

Peeler  mine,  N.  C 29 

Penfield,  S.  L.,  cited 20,  21.  24 

Pheifer  mine,  N.  C 34 

Phillips,  Wm,  cited - 8 

Phosphocerite 7,  10,  16 

"  identity  with  monazite 10 

Physical  properties  of  monazite 7,  12,  13 

Pisani,  F.,  cited 8,  19 

Price  of  North  Carolina  monazite 36 

Radominski,  F.,  cited 10,  16,  18 

Rammelsberg,  C.  F.,  cited 18,  19,  24,  25 

Rose,  G.,  cited 9 

Russia,  monazite  in 27,  30.  37 

Rutherford  county,  N.  C,  monazite  in 21,  26,  28,  32,  36 

Scharizer,  R.,  cited 12,  13,  14,  16 

Shepard,  C.  U.,  cited 9.  14,  19 


1 


INDEX.  47 


Page. 

South  America,  monazite  in 26 

South  Carolina,  monazite  in 28,  30,  32 

Spectroscopic  tests  of  monazite 23 

Sweden,  monazite  in 26 

Switzerland,  monazite  in 27 

Thoria  in  North  Carolina  monazite 21,  26 

"       determination  of  in  monazite 21,  22 

"       variation  of  in  monazite 35 

Trechmann,  CO.,  cited 

Turner,  E.  H.,  cited 

Turnerite 

"  identity  with  monazite 

United  States,  monazite  in 

United  States  of  Colombia,  S.  A.,  monazite  in 

Urdite 

"      identity  with  monazite...- 

Use  of  monazite 

Vom  Rath,  GK,  cited 

Vrba,  cited 

Watts,  H.,  cited .►. 10, 

Websky,  cited 10,  16 

Welsbach  incandescent  light 31 

Wohler,  F.,  cited 9,  15,  18 

Wiilfmg,  cited 13,  14 

Zschau,  E.,  cited 10 


,  J.U, 

7 

7,8, 

28 

8 

25, 

26 

37 

7, 

10 

10 

30, 

31 

,10, 

12 

14 

,16, 

19 

NORTH  CAROLINA  GEOLOGICAL  SURVEY 


J.   A.   HOLMES,   STATE  GEOLOGIST 


BULLETIN  No.  10 


GOLD  MINING  IN  NORTH  CAROLINA 


AND 


ADJACENT  SOUTH  APPALACHIAN  REGIONS 


BY 

HENRY   B.   C.   NITZE 

AND 

H.   A.   J.   WILKENS 


RALEIGH 

Guy  V.  Barnes,  Public  Printer 
1897. 


i 


CONTENTS. 


PAGE 

Illustrations    6 

Letter  of  Transmittal 8 

Preface   9 

Chapter  I. — Geographical  and  Geological  Description  of  the  Gold  Belts 11 

Virginia  Belt    13 

The  country-rocks 14 

The  quartz-veins     14 

The  Eastern  Carolina  belt    14 

The  Carolina  belt 15 

The  country-rocks 15 

The  gold  ores 17 

Genesis  of  the  ore-bodies 17 

The  age  of  the  ore  deposits 18 

The  South  Mountain  belt      18 

The  country-rocks 18 

The  quartz-veins 19 

The  placer  deposits    20 

Minor  belts  in  North  Carolina    20 

The  Georgia  belt     . 21 

The  country-rocks 21 

The  ore  deposits 22 

The  Carolina  belt  in  Georgia 24 

Minor  belts  in  Georgia 24 

The  Alabama  belt 25 

Chapter  II. — Historical  notes ;  mining,  metallurgical  and  statistical    26 

Early  discoveries  of  gold  in  the  South  Appalachian  region     26 

Early  mining  operations .* 27 

Early  mining  and  metallurgical  methods     29 

Hydraulic  methods     30 

Vein  mining.     Free-milling  ores    32 

Early  milling  appliances 33 

Treatment  of  sulphuret  ores   36 

Mechanical  method     36 

Chemical  treatment   3  7 

The  chlorination  process 37 

The  cyanide  process   38 

Other  chemical  processes 39 

Production  of  gold  and  silver  in  North  Carolina  and  other  Southern  states  .  .  40 


4 


4  CONTENTS. 

PAGE 

Chapter  III. — Distribution  of  gold  mines  in  North  Carolina,  and  mining  notes     .  .  43 

The  Eastern  Carolina  belt    43 

The  Carolina  belt 45 

Guilford  county 45 

Randolph  county    46 

Davidson  county     47 

Montgomery  county 51 

Stanly  county 54 

Moore  county 56 

Anson  county 57 

Rowan  county 57 

Cabarrus  county 60 

Union  county 62 

Mecklenburg  county 63 

Gaston  county    66 

Lincoln,  Catawba,  Davie,  Alexander  and  Yadkin  counties 68 

The  South  Mountain  belt 68 

Caldwell  county 68 

Burke,  McDowell  and  Rutherford  counties 68 

The  mountain  counties 70 

Chapter  IV. — Distribution  of  gold  mines  in  the  South  Appalachian  region  other 

than  in  North  Carolina,  with  mining  notes 71 

In  Maryland 71 

In  Virginia   71 

Fauquier  county 72 

Stafford  county    72 

Culpeper  county      72 

Spottsylvania  county     72 

Orange  county     73 

Louisa  county 73 

Fluvanna  and  Goochland  counties 75 

Buckingham  county 76 

Eloyd  and  Montgomery  counties 76 

In  South  Carolina 76 

Carolina  belt 77 

South  Mountain  belt 77 

In  Georgia    78 

Rabun  county 78 

Habersham  county 78 

White  county 78 

Hall  county 80 

Lumpkin  county 80 

Dawson  county 81 

Forsythe  county 81 

Gwinnett  county     81 

Cherokee  county     81 

Barton,  Cobb,  Paulding  and  Douglas  counties   82 

Carroll  county 82 

Haralson  county 82 

Meriweather  county 83 

Towne  county 84 

The  Carolina  belt  (in  Georgia)    84 


CONTENTS.  5 

PAGE 

In  Alabama, 85 

Cleburne  county 85 

Randolph  county     87 

Clay  county 89 

Talladega  county 90 

In  Tennessee 90 

Chapter  V. — The  mining  and  milling  practice  at  some  of  the  characteristic  placer 

and  free-milling  mines 91 

The  Crawford  (or  Ingram)  mine,  Stanly  county,  N.  C 91 

The  Mills  property,  Burke  county,  N.  C 95 

Placer  deposits  on  Silver  creek 97 

Placer  deposits  on  Parker  branch 101 

The  Chestatee  Company,  Lumpkin  county,  Ga 101 

The  Chestatee  river  dredge-boats,  Lumpkin  county,  Ga 106 

The  Dahlonega  method,  with  special  description  of  the  Hedwig  mine 107 

Historical  notes 108 

The  water-supply 1 08 

Mining  methods 109 

Milling  methods 110 

Dahlonega  method  at  Hedwig  mine   114 

The  Lockhart  mine,  Lumpkin  county,  Ga 115 

Chapter  VI. — Mining,  milling  and  metallurgical   treatment  of  sulphuret  ores  at 

characteristic  mines   117 

The  Reimer  mine,  Rowan  county,  N.  C 1 17 

The  Franklin  mine  (Creighton  Mining  &  Milling  Co.),  Cherokee  county,  Ga.  .  121 

The  Haile  mine,  Lancaster  county,  S.  C 125 

Description  of  the  mine  workings,  Haile  mine 129 

Method  of  working,  Haile  mine 132 

Milling  operations,  Haile  mine    135 

Labor,  costs,  etc.,  at  the  Haile  mine 142 

The  Brewer  mine,  Chesterfield  county,  S.  C 144 

Chapter  VII. — Some  conclusions  concerning  gold  mining  in  North  Carolina  and 

adjacent  South  Appalachian  regions 118 


ILLUSTRATIONS. 


PAGE 

Plate  I.     Fig.  1,  Log  rockers,  Gold  Hill ;   Fig.  2,  Chilian  mill    30 

II.     Big  Cut,  Russell  mine,  Glen  Brook,  N.  C 53 

III.  Forty-stamp  mill  and  cyanide  plant,  Russell  mine    53 

IV.  Hydraulic  mining,  Parker  mine 54 

V.     Fig.  1,  Stand-pipe  ;   and  Fig.  2,  sluice-boxes*  Parker  mine 55 

VI.     Gold  Hill  mine,  Eames  stamp-mill  and  Barnhardt  shaft 60 

VII.     Catawba  mine,  30-stamp  mill 67 

VIII.      Wrought  iron  siphon  pipe,  Dahlonega 108 

IX.      Dahlonega  method  of  mining,  giant  and  ground  sluice   109 

X.     Forty-stamp  mill  and  chlorination  plant,  Brewer  mine    147 

Fig.   1.     Gold  belts  of  the  Southern  states     12 

2.  Cross-section,  Thompson  mine 22 

3.  Map  of  North  Carolina  showing  gold  distribution    44 

4.  Map  showing  distribution  of  veins  at  Gold  Hill    59 

5.  Plan  of  Capps  mine 65 

6.  Method  of  working  gravel  at  Crawford  mine     92 

7.  Rocker  used  by  tributors,  Crawford  mine 94 

8.  Riffles  in  sluice-box,  Crawford  mine    94 

9.  Proposed  hydraulic  work  on  Mills  property 96 

10.  Flume,  Mills  property 98 

11.  Hydraulic  gravel  elevator,  Mills  property 99 

12.  Section  of  sluice-box,  Mills  property 100 

13.  Plan  of  hydraulic  lift 103 

14.  Plan  of  setting  hydraulic  lift     105 

15.  Plan  of  portable  tailings  flume 105 

16.  Vertical  cross-section  of  the  Hall  stamp-mill    110 

17.  Vertical  longitudinal  section  of  the  Hall  stamp-mill 112 

18.  Vertical  section,  Reimer  mine    118 

19.  Mecklenburg  Iron  Works,  750-pound  battery 120 

20.  Vertical  section,  Franklin  mine     122 

21.  Haile  mine,  outline  map  of  region    12  7 

22.  Plan  and  section  of  Beguelin  part  of  Haile  mine 128 

23.  Plan  of  Cross  mine,  Haile  Gold  Min.  Co 130 

24.  Method  of  stoping  at  Cross  mine 133 

25.  Vertical  skip  used  at  Haile  mine 134 

26.  Section  of  60-stamp  mill,  Haile  mine 136 

27.  Double-hearth  roasting  furnace,  Haile  mine 13S 

28.  Chlorination  plant  at  Haile  mine,  longitudinal  section 139 

"29.      Chlorination  plant  at  Haile  mine,  cross  section    140 

30.  Chlorination-barrel,  Haile  mine    141 

31.  Plan  of  Brewer  mine,  Chesterfield  county,  S.  C 146 


jfartK  Carolina 


J I 


BOARD  OF  MANAGERS. 


Governor  D.  L.  Russell,  ex-officio  Chairman, 

Charles  McEamee,        . 

J.  Turner  Morehead,  .... 


Raleigh. 

Biltmore. 

Leaksville. 


STATE  GEOLOGIST. 


J.  A.  Holmes, 


Chapel  Hill. 


LETTER  OF  TRANSMITTAL. 


To  His  Excellency,  Hon.  D.  L.  Russell, 

Governor  of  North  Carolina. 

Sir: — I  have  the  honor  to  transmit  for  publication  as  bulletin  10  of 
the  Geological  Survey  series,  a  report  on  the  subject  of  Gold  Mining 
and  Mining  Methods  in  North  Carolina  and  adjacent  South  Appalachian 
regions.  The  Survey  has  received  many  requests  for  information  con- 
cerning this  subject,  and  it  is  in  response  to  these  that  I  recommend  the 
publication  of  this  report.  Many  applications  for  copies  of  it  have  been 
received  in  advance  of  its  appearance. 

Yours  obediently, 

J.  A.  Holmes, 

State  Geologist, 

Raleigh,  N.  C, 

July  1,  1897. 


i 


PREFACE. 

During  the  past  few  years  the  Survey  has  received  from  persons 
interested  in  gold  mining  in  North  Carolina,  numerous  inquiries  con- 
cerning the  mining  and  metallurgical  methods  which  have  proven  most- 
successful  in  operating  gold  mines  in  this  and  other  South  Appalachian 
regions.  In  response  to  these  inquiries,  an  investigation  was  undertaken 
of  this  subject  in  1895,  by  Mr.  H.  B.  0.  Nitze,  of  the  Survey,  and  Mr. 
H.  A.  J.  "Wilkens,  a  mining  expert  of  Baltimore,  who  visited  during  that 
year  the  more  important  mining  regions  in  North  Carolina  and  other 
Southern  States.  A  preliminary  report  of  their  examinations  was  read 
at  the  Atlanta  meeting  of  the  American  Institute  of  Mining  Engi- 
neers (October,  1895),  and  was  published  in  the  Transactions  of  the 
Institute  for  that  year. 

In  the  present  publication  that  paper  has  been  partly  reproduced,  but 
it  has  been  largely  rewritten,  elaborated  and  brought  down  to  the  end 
of  1896.  No  attempt  has  been  made  to  describe  all  of  the  mines  or  even 
to  present  detailed  descriptions  of  all  of  the  more  important  mining 
regions  to  be  found  in  North  Carolina  and  adjacent  States.  Only  such 
mining  and  metallurgical  methods  practiced  in  this  and  the  other  States 
are  here  described  as  it  is  believed  will  be  found  useful  in  a  study  of 
the  best  methods  for  use  in  the  development  of  the  North  Carolina  gold 
fields.  This  report  may  be  regarded  as  being  in  a  measure  supplemental 
to  Bulletin  3  (Gold  Deposits  of  North  Carolina),  published  by  the 
Survey  in  1896,  which  described  with  more  detail  the  gold-mining 
regions  in  this  State. 

The  descriptions  given  in  the  report  are  based  almost  wholly  upon  the 
personal  examinations  of  Messrs.  Nitze  and  Wilkens.  They  have,  how- 
ever, made  use  of  data  relating  to  the  different  mining  regions  to  be 
found  in  Mr.  Geo.  F.  Becker's  valuable  "  Reconnoissance  of  the  Gold 
Fields  of  the  Southern  Appalachians,"  and  the  reports  by  the  several 
State  Geological  Surveys,  the  sources  of  information  being  indicated  in 
each  case  by  footnotes.     Persons  desiring  to  consult  other  publications 


10  .  PREFACE. 

relating  to  this  field  will  find  a  full  bibliography  in  the  above-mentioned 
report  of  Mr.  Becker's,  published  by  the  U.  S.  Geological  Survey. 

Messrs.  Mtze  and  Wilkens  have  been  aided  in  the  preparation  of  their 
statement  concerning  the  Haile  mine  in  South  Carolina  by  Mr.  A.  Thies. 
Capt.  John  Wilkes,  of  the  Mecklenburg  Iron  Works,  Charlotte,  X.  C, 
has  also  aided  them  by  the  loan  of  drawings,  maps  and  in  other  ways. 
Mr.  Geo.  B.  Hanna,  of  the  U.  S.  Assay  Office,  at  Charlotte,  X.  C,  has 
kindly  furnished  numerous  notes  concerning  the  history  of  mining  and 
metallurgical  methods  in  the  entire  South  Appalachian  region.  In 
behalf  of  the  Survey  and  of  the  authors,  I  desire  to  thank  these  gen- 
tlemen and  many  others,  in  different  parts  of  the  region,  who  have  in 
various  ways  rendered  assistance  in  the  collection  and  preparation  of 
information  for  this  report.  I  desire  further  to  thank  the  editors  of 
The  Transactions  of  the  American  Institute  of  Mining  Engineers  and 
The  Engineering  Magazine  for  permission  to  use  electrotypes  of  plates 
prepared  for  those  publications. 

One  of  the  existing  needs  of  the  North  Carolina  gold  field  is  the 
establishment  at  central  points  in  this  region  of  practical  plants  that  will 
successfully  treat  the  low-grade  sulphur et  ores — plants  that  will  do 
custom  work  at  reasonable  prices,  and  where  individual  miners  can 
ship  their  ore  and  be  paid  for  the  same  according  to  its  value,  as  is  the 
case  in  the  great  mining  regions  of  the  West. 

J.  A.  Holmes. 


i 


GOLD  MINING  IN  NORTH  CAROLINA  AND  ADJACENT 
SOUTH  APPALACHIAN  REGIONS. 

By  H.  B.  C.  Nitze  and  H.  A.  J.  Wilkens. 


CHAPTER  I. 


GEOGEAPHICAL  AND  GEOLOGICAL  DESCRIPTION  OF 
THE  GOLD  BELTS. 

The  gold  fields  of  the  Southern  Appalachians  are  situated  in  the  area 
of  the  crystalline  rocks  extending  from  the  vicinity  of  "Washington  in  a 
general  southwesterly  direction,  through  the  piedmont  and  mountain 
regions  of  Maryland,  Virginia,  North  Carolina,  Tennessee,  South  Caro- 
lina, Georgia,  and  Alabama,  to  the  vicinity  of  Montgomery. 

The  greatest  width  of  the  belt,  as  a  whole,  is  attained  in  North  Caro- 
lina, South  Carolina  and  Georgia,  where  it  is  from  100  to  150  miles, 
narrowing  down  in  Virginia  and  Maryland  on  the  northeast  and  in 
Alabama  on  the  southwest  (see  map,  fig.  1). 

In  chapters  III  and  IV  the  gold-mining  counties  of  these  States  are 
given. 

The  general  term  crystalline  rocks  includes  gneisses,  argillaceous, 
hydro-micaceous,  chloritic,  siliceous  and  other  schists  and  slates,  lime- 
stone, granite,  diorite,  diabase  and  other  eruptives,  as  well  as  certain 
volcanic  porphyries,  etc.,  and  pyroclastic  breccias.  The  age  of  these 
rocks  is  Archaean,  Algonkian,  and  possibly  in  part  Paleozoic.  On  the 
east  they  are  covered  by  the  Coastal  Plain  and  in  places  by  small  patches 
of  the  Jura-trias  (Newark),  which  latter  also  occur  within  the  area  in 
small  isolated  basins,  notably  in  Virginia.  On  the  west  they  are  bor- 
dered by  the  Paleozoic  rocks. 

The  rocks  of  the  gold  belt  are  decomposed  to  depths  often  reaching 
50  and  100  feet.  Mr.  Becker  has  proposed  and  used  the  term  "sapro- 
lite,"  x  signifying  literally  "  rotten  rock,"  as  a  general  name  for  such 
thoroughly  decomposed,  earthy,  but  untransported  rock. 

Eor  geological  reasons  and  for  descriptive  convenience  this  gold  belt 

1  "'Reconnoissance  of  the  Gold  Fields  of  the  Southern  Appalachians,  by  G.  F.  Becker,  Six- 
'         teenth  Annual  Report  of  the  77.  S.  Geological  Survey,  1894-5,  part  iii,  pp.  289-90. 


12 


GOLD    MINING    IN    NORTH    CAROLINA. 


GEOGRAPHICAL    AND    GEOLOGICAL    DESCRIPTION    OF    GOLD    BELTS. 


13 


of  the  Southern  Appalachians  is  differentiated  into  the  following  com- 
ponent belts: 

1.  The  Virginia  Belt.  4.  The  South  Mountain  Belt. 

2.  The  Eastern  Carolina  Belt.  5.  The  Georgia  Belt. 

3.  The  Carolina  Belt.  6.  The  Alabama  Belt. 

Other  divisions  might  be  made  as,  for  instance,  the  isolated  belts  of 
auriferous  rocks  west  of  the  Blue  Ridge  in  Virginia,  North  Carolina, 
Georgia  and  Tennessee,  and  various  minor  belts  in  Georgia  and  Ala- 
bama; but  such  subdivision  is  unnecessary  for  the  purposes  of  this  paper. 

In  Bulletin  3,  "  The  Gold  Deposits  of  North  Carolina,"  the  Carolina 
Belt  has  been  differentiated  into  the  Carolina  Slate,  the  Carolina  Igneous 
and  the  Kings  Mountain  belts.  For  the  purpose  of  this  paper,  how- 
ever, where  the  geological  descriptions  of  these  various  belts  can  only  be 
briefly  taken  up,  the  above  six  main  divisions  will  suffice,  and  for  fuller 
and  more  detailed  descriptions  the  reader  is  referred  to  the  following 
papers : 

u . Reports  on  the  Surveys  of  South  Carolina,"  by  O.  M.  Lieber,  Co- 
lumbia, S.  C,  1856,  1857,  1858,  and  1859. 

"A  Reconnoissance  of  the  Gold  Fields  of  the  Southern  Appalach- 
ians," by  George  F.  Becker.1 

"  The  Gold  Deposits  of  North  Carolina,"  by  H.  B.  C.  Mtze  and  G.  B. 
Ilanna.2 

"  The  Lower  Gold  Belt  of  Alabama,"  by  William  B.  Phillips.3 

"  Mineral  Resources  of  the  Upper  Gold  Belt  (of  Ala.),"  by  Win.  M. 
Brewer  and  others.4 

Work  has  been  in  progress  by  the  Geological  Surveys  of  Georgia  and 
Alabama  on  the  gold  fields,  and  reports  from  these  respective  bureaus 
are  expected  to  be  published  shortly. 

1.    THE   VIRGINIA   BELT. 

This  belt  begins  in  Montgomery  county,  Maryland,  and  extends  in  a 
southwesterly  direction,  parallel  to  and  on  the  east  side  of  the  Blue 
Ridge,  to  the  North  Carolina  line.  The  best  and  most  reliable,  though 
incomplete,  information  regarding  the  geology  of  this  region  is  given  in 
the  early  reports  of  Prof.  William  B.  Rogers  (1835,  1836  and  1S40V 

The  width  of  the  belt  is  from  9  to  20  miles,  covering  an  area  of  some 
4000  square  miles,  and  its  best  developed  portion  is  in  Fauquier,  Cul- 


1  U.  S.  Geological  Survey,  Sixteenth  Annual  Report,  1894-95,  part  iii,  pp.  251-331. 

2  North  Carolina  Geological  Survey,  Bull.  No.  3, 1896. 

3  Geological  Survey  of  Alabama,  Bull.  No.  3, 1892. 

4  Geological  Survey  of  Alabama,  Bull.  No.  5, 1896. 

5  The  Geology  of  the  Virginias,  D.  Appleton  &  Co.,  New  York,  1884,  pp.  74-80,  131-132,  458-460. 


14  GOLD    MINING    IN    NOKTH    CAROLINA. 

peper,   Stafford,   Orange,   Spottsyrvania,   Louisa,   Fluvanna,   Goochland 
and  Buckingham  counties. 

THE    COUNTRY-ROCKS. 

The  rocks  of  the  Virginia  belt  are  mica-gneisses  and  schists,  often 
garnetiferous,  hydro-micaceous  and  chloritic.  The  strike  is  X.  20°-30° 
E.,  and  the  dip  easterly  at  varying  angles.  Mr.  S.  F.  Emmons1  gives 
the  prevailing  strike  in  Montgomery  county,  Maryland,  as  north  and 
south,  and  the  dip  nearly  vertical  or  very  slightly  inclined  to  the  east- 
ward. Granite  and  diabase  dikes  occur  in  the  region,  and  these  are 
sometimes  sheared.  In  some  private  notes  on  the  Arminius  pyrite  mine, 
in  Louisa  county,  Va.,  Mr.  Becker  says: 

"  The  principal  country  rock  is  a  series  of  micaceous  schists Indica- 
tions are  not  wanting  that  a  portion  of  these  schists  is  of  sedimentary  origin. 
....  On  the  other  hand,  it  is  equally  certain  that  the  most  prominent  charac- 
teristics of  the  schists  are  of  dynamic  origin.  .  .  .  Much  of  the  schist  looks  as  if 
it  were  derived  dynamically  from  granite." 

THE    QUARTZ-VEINS. 

The  auriferous  quartz-veins  conform  in  the  main  to  the  strike  and  dip 
of  the  enclosing  rock.  However,  their  origin  is  not  coeval,  the  schistose 
structure  antedating  the  formation  of  the  veins.  Neither  must  their 
approximate  conformity  to  the  country  be  taken  in  the  absolute  sense, 
for  they  often  cut  the  schists  at  small  angles  both  in  dip  and  strike. 
The  structure  of  the  veins  is  irregularly  lenticular,  varying  from  a  few 
inches  to  several  feet  in  thickness.  The  wall-rock  is  often  impregnated 
with  auriferous  pyrites  to  considerable  extent.  Some  of  these  veins  are 
of  remarkable  persistency  and  continuity,  as,  for  instance,  the  Fisher  lode 
in  Louisa  county,  which  has  been  opened  for  a  distance  of  some  five 
miles  along  the  strike  to  a  maximum  depth  of  220  feet  by  the  Warren 
Hill,  Louisa,  Slate  Hill,  Luce  and  Harris  mines. 

The  gravel  placer  deposits  of  the  Virginia  belt  are  in  all  respects  simi- 
lar to  those  of  other  gold  regions. 

A  small  isolated  gold  belt  is  situated  on  the  west  side  of  the  Blue 
Bidge  in  Montgomery,  Floyd  and  Grayson  counties,  but  it  is  of  little 
economical  importance  and  will  not  warrant  more  than  this  passing 
mention.  The  auriferous  copper  ores  of  Ashe  and  Watauga  counties, 
N".  C.,  also  appear  to  belong  here. 

2.    THE   EASTERN   CAROLINA   BELT. 

This  forms  a  small  and  narrow  area  in  Halifax,  Warren,  ^ash  and 
Franklin  counties.     It  is  covered  on  the  east  by  the  Coastal  Plain  and 

1"Noteson  the  Gold-Deposits  of  Montgomery  county,  Md.,"  by  S.F.Emmons.  Trans.  Am. 
Inst.  Min.  Eng.,  xviii,  391-411. 


GEOGRAPHICAL    AND    GEOLOGICAL    DESCRIPTION    OF    GOLD    BELTS.         15 

bounded  on  the  west  by  the  Louisburg  granite.  The  country  rock  is 
diorite,  in  great  part  sheared  to  a  chloritic  schist  (as  at  the  Mann- 
Arrington  mine).  The  strike  of  the  schists  is  !N".  50°-60°  E.,  and  the 
dip  25°-40°  S.E.  Other  intrusives,  such  as  diabase,  occur  in  the  region. 
The  quartz-veins. — These  occur  (1)  as  lenses,  from  minute  size 
up  to  12  inches  in  thickness,  interlaminated  in  the  schists  or  cutting 
them  at  small  angles;  (2)  as  a  reticulated  network  in  the  massive  rocks. 
It  is  stated  that  the  saprolites  are  auriferous  over  large  areas  and  will 
repay  hydraulic  mining. 

3.    THE   CAROLINA   BELT. 

This  belt  is  one  of  the  most  extensive  and  important  in  the  Southern 
Appalachians,  though  lying  far  to  the  east  of  the  Blue  Ridge.  It  is 
situated  in  the  central  Piedmont  region,  and  extends  from  the  Virginia 
line  in  a  southwesterly  direction  across  the  central  part  of  North  Carolina 
into  the  northern  part  of  South  Carolina,  where  it  sinks  beneath  the 
Coastal  Plain,  making  its  re-appearance  in  Abbeville  county,  S.  C,  and 
in  Wilkes,  McDuffie  and  adjacent  counties  in  Georgia,  near  Augusta. 
There  are  no  mountain  chains  in  the  Carolina  belt,  the  only  prominences 
of  consequence  being  a  low  range  of  hills  known  as  the  Uharie  moun- 
tains, in  Montgomery  county,  N".  C,  and  the  isolated  peaks  of  Crowders 
and  Kings  mountains  in  Gaston  county,  :N".  C,  extending  into  York 
county,  S.  C. 

The  belt  varies  in  width  from  8  to  50  miles;  it  is  bounded  on  the  east 
by  the  Jura-trias  (Newark)  and  the  coastal  plain  formations. 

THE    COUNTRY-ROCKS, 

The  gold-bearing  rocks  of  the  Carolina  belt  are  (1)  argillaceous,  seri- 
citic  and  chloritic  metamorphosed  slates  and  schists;  (2)  devitrified  an- 
cient volcanics  (rhyolite,  quartz-porphyry,  etc.,  and  pyroclastic  brec- 
cias); (3)  igneous  plutonic  rocks  (granite,  diorite,  diabase,  etc.);  (4)  sili- 
ceous magnesian  limestone;  (5)  sedimentary  pre-Jura-trias  slates.  The 
Jura-trias  conglomerates  along  the  eastern  boundary  have  also  been 
found  to  contain  gold,  but  not  in  quantities  of  economical  importance. 

The  argillaceous  and  sericitic  1  slates  and  schists,  though  in  general 
highly  metamorphosed  and  sheared,  show  many  evidences  of  sedimen- 
tary origin.  The  siliceous  magnesian  limestones  (Kings  mountain, 
etc.),  must  be  included  here.  All  of  these  rocks  are  non-fossiliferous 
and  must  be  provisionally  classed  as  Algonkian.  They  are  often  silici- 
fied  in  varying  degrees  up  to  a  completeness  which  renders  the  rock  so 

^he  general  term  "talc"  schists,  so  often  used,  is  very  loosely  applied,  and  generally  in- 
correctly, as  the  true  "talc  "schists  are  comparatively  rare;  it  should,  from  a  niineralogical 
standpoint,  more  properly  be  hydro-mica  or  sericite  schists. 


16  GOLD    MIXING-    IN    NORTH    CAROLINA. 

hard  that  it  resists  scratching  with  a  knife.  The  chloritic  schists  are 
more  truly  the  crystalline  schists,  and  probably  represent  the  sheared 
basic  eraptives.  They  are  even  porphyritic  and  brecciated  in  places. 
They  are  not  so  abundant  as  the  argillaceous  schists,  and  are  richer  in 
accessory  rnetamorphic  minerals,  such  as  garnet  and  epidote. 

The  general  strike  of  the  schist osity  is  ~N.  20°-55°  E.,  and  the  pre- 
dominating dip  to  the  !N".  W.  from  55°-85°.  In  many  cases  the  force 
producing  schistosity  and  slaty  cleavage  appears  to  have  acted  downward 
from  the  2s".W.?  developing  normal  faulting  with  but  little  deformation. 

The  volcanic  rocks  occupy  irregular  patches  along  the  eastern  border 
of  the  belt,  in  close  proximity  to  the  western  edges  of  the  Jura-trias 
basins.  They  comprise  both  acid  and  basic  types.  The  acid  rocks  are 
generally  devitrined  to  such  an  extent  that  their  real  character  is  no 
longer  recognizable  to  the  naked  eye,  and  they  appear  as  ordinary  cherts 
or  hornstones,  although  flow-structure  is  at  times  still  discernible.  Micro- 
scopic examination  shows  them  to  belong  to  the  class  of  rhyolites  and 
quartz-porphyries.  They  are  sometimes  sheared  into  schists,  as  for  in- 
stance at  the  Haile  mine,  S.  C.  The  basic  types  are  dark  green  in  color 
and  perhaps  pyroxenic  in  composition;  they  are  sometimes  massive  por- 
phyrites,  but  more  generally  sheared  into  schists.  The  pyroclastic  brec- 
cias consist  of  angular  fragments  of  the  acid  rhyolites  and  porphyries  in 
a  basic  matrix.  The  age  of  these  ancient  volcanics  is  believed  to  be  pre- 
Cambrian.  They  seem  to  be  analogous  to,  and  probably  contempora- 
neous with,  similar  rocks  of  the  South  mountain  in  Maryland  and  Penn- 
sylvania, and  other  points  along  the  Atlantic  coast.  The  igneous  plu- 
tonic  rocks  lie  on  the  western  side  of  the  central  slates;  they  consist  of 
granites,  diorites,  gabbros,  diabases,  etc.  In  point  of  age  they  are  sup- 
posed to  be  younger  than  the  slates  and  schists  on  the  east.  Diabase 
dikes  are  common  in  the  Carolina  belt,  and  appear  in  general  to  have 
exercised  a  favorable  influence  on  the  richness  of  the  ore-bodies  which 
they  intersect;  the  ores  often  are  richer  in  the  vicinity  of  the  dikes.  At 
the  Haile  mine,  in  Lancaster  county,  S.  C,  this  is  very  marked. 

The  sedimentary  pre-Jura-trias  slates,  mentioned  above  as  the  fifth 
class  of  gold-bearing  rocks,  are  perhaps  best  developed  near  Monroe, 
ITnion  county,  !N".  C,  and  have  therefore  been  called  the  Monroe  slates. 
These  slates  are  but  little  indurated  and  lie  in  flat-bedded  alternating 
synclinals  and  anticlinals.  They  cover  a  considerable  area,  extending 
from  Monroe  northward  and  eastward,  and  appearing  in  Stanly  and 
Montgomery  counties.  They  dip  under  the  Jura-trias  conglomerate 
near  Polkton,  20  miles  east  of  Monroe,  and  might  be  looked  upon  as 
Lower  Paleozoic ;  but  the  absence  of  fossils,  so  far  as  present  search  has 
gone,  must,  for  the  time  being,  place  them  provisionally  in  the  Algon- 
kiar. 


a 


GEOGRAPHICAL  AND  GEOLOGICAL  DESCRIPTION  OF  GOLD  BELTS.    1< 
THE  GOLD  ORES. 

The  gold  ores  in  the  Carolina  belt  exist  in  two  principal  structural 
forms:  (1)  as  quartz  fissure-veins;  (2)  as  pyritic  impregnations,  ac- 
companied by  irregular  stringer-like  and  lenticular  quartz  intercalations 
in  the  country  schists  and  slates.  The  fissure-veins  in  the  slates  and 
schists  are  generally  difficult  to  distinguish  as  such.  Their  structure  is 
much  more  evident  in  the  granitic  and  other  eruptives.  In  the  schists 
the  larger  and  more  regular  quartz  lodes  lie  apparently  interlaminated 
with  the  country,  or  have  the  appearance  of  lenticular  intercalations; 
however,  even  here  they  can  usually  be  shown  to  intersect  the  schis- 
tosity,  generally  at  very  low  angles. 

The  age  of  the  ore  deposits  is  later  than  that  of  the  force  which  pro- 
duced schistosity,  from  the  fact  that  fragmental  inclusions  of  sheared 
country-rock  are  not  rare  in  quartz.  The  fissuring  force  was,  there- 
fore, subsequent  to  the  shearing  force.  Certain  maximum  lines  of  fault- 
ing may  have  been  developed,  which  made  room  for  the  larger  fissure- 
veins,  on  either  side  of  which  smaller  dislocations  formed  belts  of  varia- 
ble width.  It  is  certainly  most  natural  that,  in  a  rock  like  slate  or  schist, 
the  rupturing  force  should  have  been  exerted  along  the  lines  of  least 
resistance,  that  is,  along  the  cleavage  planes,  and  that  the  predominating 
fissures  should,  therefore,  have  been  formed  in  that  direction.  Isolated 
instances  of  cross-fissures  occur,  but  they  are  rare. 

A  very  usual  occurrence  of  the  ores  is  that  of  irregular,  finely-divided 
disseminations  of  auriferous  sulphurets  and  fine  gold,  accompanied  by 
small  stringers  and  lenses  of  quartz  in  the  country  slates  and  schists, 
which  are  usually  silicified,  at  least  to  some  extent.  This  form  of  deposit 
bears  close  resemblance  to  the  Scandinavian  "  fahlbands,"  which  are  de- 
scribed as  belts  of  schists  impregnated  with  sulphides.  In  the  Southern 
Appalachian  field  they  form  the  small  and  large  bodies  of  low-grade  ores 
(Haile  mine,  Russell  mine,  etc.).  The  shape  of  these  ore-bodies  is  lenti- 
cular; their  outline,  however,  does  not  necessarily  conform  with  the 
strike  and  dip  of  the  schists,  but  is  determined  rather  by  the  degree  of 
impregnation.  Very  often,  also,  the  wall-rock  of  the  quartz  fissure-veins 
is  impregnated  for  some  distance  with  auriferous  sulphurets. 

The  gravel  placers  of  the  Carolina  belt  present  no  features  differing 
from  those  of  similar  deposits  in  other  gold  regions. 

GENESIS    OF    THE    ORE-BODIES. 

"No  definite  proof  of  metasomatic  formation  of  the  ores  has  been  ob- 
served; and  the  most  reasonable  hypothesis  for  their  formation  is  that 
of  the  ascension  and  percolation  of  heated  carbonated  and  alkaline  waters 
carrying  silica,  metallic  elements  and  sulphides  in  solution,  and  the  depo- 


IS  GOLD    MINING    IN    NORTH    CAROLINA. 

sition  of  their  mineral  contents  in  the  open  spaces  through  which  they 
circulated,  by  relief  of  pressure,  reduction  of  temperature,  and  perhaps- 
certain  chemical  reactions.  The  frequent  siliciflcation  of  the  slates  and 
schists  has  been  noted,  and  must  be  ascribed  to  this  permeation  of  the 
silicifled  waters. 

The  character  of  the  quartz  varies  from  saccharoidal  to  vitreous,  usu- 
ally inclining  to  the  latter.  The  sulphurets  are  chiefly  pyrites;  chalco- 
pyrite,  galena,  mispickel  and  zinc-blende  occur  in  certain  localities,  not- 
ably at  the  Silver  Hill  and  Silver  Valley  mines,  in  Randolph  county. 
!N".  C.  Copper  ores  (chalcopyrite)  in  some  of  the  Xorth  Carolina  mines 
are  auriferous  to  such  an  extent  as  to  make  them  valuable  for  gold  also. 
as  for  instance  at  the  Conrad  Hill.  Tellurides  have  been  found  in  very 
small  quantities,  as  at  the  Kings  Mountain  mine,  X.  C.  Among  the 
more  common  gangue  minerals,  besides  quartz  and  sulphurets,  are 
chlorite,  barite  and  carbonates.1 

THE    AGE    OF    THE    ORE    DEPOSITS. 

The  formation  of  the  ores  took  place  subsequent  to  the  production  of 
schistosity.  The  fact  that  the  Jura-trias  conglomerates,  on  the  east, 
contain  gold  proves  that  the  origin  of  the  gold  must  have  been  pre-Jura 
Triassic.  The  presence  of  gold-bearing  fissure-veins  in  the  Monroe  slate? 
shows  that  their  age  must  be  Algonkian  or  later.  The  existence  of  ore- 
bodies  in  the  pre-Cambrian  volcanic  rocks  furnishes  another  clue;  and 
thus  it  becomes  probable  that  the  age  of  the  gold  ores  in  the  Carolina 
belt  is  Algonkian. 

4.    THE    SOUTH    MOUNTAIN    BELT. 

This  belt  is  situated  in  the  western  part  of  North  Carolina,  and  takes 
its  name  from  the  South  mountains,  one  of  the  eastern  outliers  of  the 
Blue  Ridge.  The  principal  mining  region  embraces  an  area  of  250  to 
300  square  miles,  in  Burke,  McDowell  and  Rutherford  counties,  extend- 
ing from  Morganton  to  near  Rut-kerf ordton,  a  distance  of  about  25 
miles,  with  an  average  width  of  10  to  12  miles.  The  gold  veins  of 
northern  Burke  and  Caldwell  counties  on  the  north,  and  Cleveland  and 
Polk  counties,  X.  C,  on  the  south,  as  well  as  Spartanburg.  Greenville 
and  Pickens  counties,  S.  C,  might  be  considered  as  belonging  to  this 
general  belt;  but  no  extensive  operations  have  been  carried  on  there. 

THE    COUNTRY-ROCKS. 

In  the  South  mountain  region,  the  crystalline  rocks  are  for  the  most 
part  Archaean  micaceous  (biotite)  and  hornblendic  gneisses  and  schists. 

1  Mr.  Becker,  in  the  paper  referred  to  above,  pp.  274-278,  tabulates  no  less  than  60  gangue 
minerals,  besides  quartz,  pyrite,  and  the  ordinary  products  of  decomposition. 


I 


1 


GEOGRAPHICAL    AND    GEOLOGICAL    DESCRIPTION    OF    GOLD    BELTS.         19 

having  an  eminently  lenticular  structure.  They  are  often  garnetiferous 
and  contain  also  many  of  the  rarer  accessory  minerals,  such  as  zircon, 
monazite,  xenotime,  etc.  These  gneisses  are  considered  to  have  been 
igneous  granites  and  diorites,  subsequently  rendered  schistose  by 
dynamo-metamorphism.  The  general  strike  of  the  sehistosity  is  N.  10°- 
25°  "W.,  and  the  dip  20°-25°  N.E.  To  the  northwest  of  South  Muddy 
creek  and  Vein  mountain,  however,  the  strike  is  generally  N.  E.  and 
the  dip  S.  E.  This  is  the  case  also  in  the  northern  part  of  the  general 
belt,  in  Caldwell  county. 

Isolated  masses  of  pyroxenite  and  amphibolite  occur  as  rounded  inclu- 
sions or  blebs,  from  less  than  1  to  nearly  100  feet  in  diameter,  in  the 
gneiss.  They  are  looked  upon  as  basic  segregations  from  the  original 
igneous  magma  out  of  which  the  gneisses  were  formed.  They  alter  to 
talc  and  serpentine. 

Pegmatites  are  of  frequent  occurrence  in  the  gneisses,  and  like  them 
their  structure  is  usually  lenticular.  At  several  points  there  are  indi- 
cations of  pegmatite  dikes.  Granite  dikes  occur  in  the  South  mountain 
region;  and  in  the  northern  part  of  the  belt,  in  Caldwell  county,  a  very 
persistent  and  continuous  dike  of  aphanitic  olivine  diabase  has  been 
observed.  Brown  mountain,  in  the  northern  part  of  Burke  county,  is 
made  of  granite. 

THE    QUARTZ-VEINS. 

The  auriferous  quartz-veins  of  the  South  mountain  belt  form  a  system 
of  parallel  fissures  of  remarkable  regularity,  striking  t>T.  G0°-70°  E.  and 
dipping  70°-80°  N.W.  Their  thickness  varies  from  that  of  a  knife- 
edge  to  4  feet.  The  great  majority  are  from  less  than  1  to  3  inches  in 
thickness,  lying  in  zones  of  scores  of  small  veins;  the  larger  ones  (1  to  4 
feet)  are  few  and  far  between.  Normal  faulting  has  been  observed  in  a 
few  instances.  The  ore  is  quartz,  usually  of  a  milky  white  color,  gener- 
ally saccharoidal  and  seldom  vitreous  or  glassy.  It  is  often  stained 
brown  and  is  cellular  from  decomposed  sulphurets.  The  sulphurets  are 
pyrite,  galena,  chalcopyrite,  and  zinc-blende.  All  observations  go  to 
show  that  the  vein-matter  is  formed  from  ascending  mineralized  solu- 
tions. There  is  no  evidence  of  the  replacement  of  the  country  rock  by 
ore. 

In  the  South  mountain  region  proper  there  are  five  parallel  lines  or 
zones  along  which  these  quartz-veins  appear  to  be  concentrated: 

1.  The  Morganton  zone,  passing  through  Morganton,  along  Little 
Silver  creek  and  through  the  Neighbor's  place  to  North  Muddy  creek. 

2.  The  Huntsville  zone,  passing  over  the  southern  end  of  Huntsville 
mountain. 

3.  The  Pilot  mountain  zone,  passing  over  Halls  knob,  Whites  knob, 


> 


20  GOLD    MINING    IN    NORTH    CAROLINA. 

Pilot  mountain,  Brackettown,  and  Vein  mountain,  to  and  beyond  the 
Second  Broad  river. 

4.  The  Golden  valley  zone,  passing  across  the  upper  end  of  the  Gol- 
den valley  (valley  of  the  First  Broad  river)  and  crossing  Cane  and  Camp 
creeks  to  the  Second  Broad  river. 

5.  The  Idler  mine  zone,  about  3  miles  north  of  Butkerf  ordton. 

The  great  majority  of  these  auriferous  quartz-veins  are  too  small  to 
be  profitably  worked  individually.  Of  the  larger  and  more  promising 
veins  which  have  been  worked,  the  "  Nichols,"  at  Vein  mountain  (18 
inches  to  3  feet),  and  the  "Idler,"  near  Butherfordton  (22  inches),  may 
be  mentioned. 

THE    PLACER    DEPOSITS. 

The  principal  mining  ground  of  the  South  mountain  region  is  that 
of  the  placer  deposits.  These  are  of  three  classes:  1.  The  gravel  de- 
posits of  the  stream-beds  and  bottom-lands,  deposited  by  nuviatile  action. 
2.  The  gulch  and  hillside  deposits,  or  accumulations  due  to  secular  dis- 
integration and  motion  induced  by  frost  action  and  gravity.  3.  The 
upper  decomposed  layer  of  the  country-rock  in  place,  the  saprolites. 

In  the  first  class  the  gravel  is  water-worn,  rounded  to  subangular, 
and  the  dejDOsits  are  from  1  to  2  feet  in  thickness.  In  the  second  class 
the  gravel  is  usually  quite  angular,  and  the  deposits  are  from  a  few 
inches  to  several  feet  in  thickness.  In  the  third  class  gravel  is  of 
course  absent,  the  washable  ground  consisting  of  the  upper  decomposed 
layer  in  place,  the  gold  being  derived  directly  from  the  partially  dis- 
integrated quartz-veins. 

5.  MINOR  BELTS  IN  NORTH  CAROLINA. 

On  the  west  side  of  the  Blue  Bidge,  in  Henderson  county,  N.  C, 
gold  has  been  mined  at  the  Boylston  mine.  The  country  rocks  are 
fine-grained  mica-  and  hornblende-schists,  in  part  much  crumpled.  The 
general  strike  is  K  20°-30°  E.,  and  the  dip  is  K¥.  The  schists  are 
cut  by  a  granite  dike.  The  valley  of  Boylston  creek  is  made  up  of 
schistose  limestone,  underlying  these  crumpled  schists.  These  rocks 
are  probably  to  be  classed  in  the  Ocoee,  which  by  some  is  supposed  to 
be  Algonkian  and  by  others  Baleozoic,  and  by  others  still,  it  is  believed 
to  contain  formations  of  different  ages  ranging  between  these  two. 
This  isolated  belt,  however,  has  little  economic  importance  in  connec- 
tion with  gold  deposits. 

Another  belt  of  auriferous  rocks  is  that  in  which  some  unimportant 
placer-mining  operations  have  been  prosecuted  in  Swain,  Jackson, 
Macon,  Clay,  and  Cherokee  counties,  !N\  C.  The  country-rock  is  sup- 
posed to  be  largely  Ocoee.     In  Tennessee  the  petty  stream  deposits  of 


i 


GEOGRAPHICAL    AND    GEOLOGICAL    DESCRIPTION    OF    GOLD    BELTS.        21 

Polk,  McMinn,  Monroe  and  Blount  counties  are  probably  in  the  same 

horizon. 

6.    THE    GEORGIA   BELT. 

The  Georgia  belt  is  probably  of  next  or  equal  economic  importance 
to  the  Carolina  belt.  Beginning  in  Rabun  and  Habersham  counties, 
in  the  northeastern  corner  of  the  State,  it  extends  in  a  southwesterly 
direction  through  the  important  mining  town  of  Dahlonega,  and  thence 
to  the  Alabama  line  in  the  vicinity  of  Tallapoosa.  This  is  in  the  Pied- 
mont region  of  the  State,  lying  on  the  southeast  side  of  the  Blue  Ridge. 
Although  the  maximum  width  (N.W.  and  S.E.)  over  which  the  mines 
are  distributed  is  as  great  as  30  miles,  the  principal  portion  of  the  belt, 
which  extends  from  near  Canton,  in  Cherokee  county,  through  Dah- 
lonega and  JNTacoochee,  to  Clayton,  in  Rabun  county,  is  concentrated 
in  a  width  of  4  miles  or  less.  It  is  to  this  latter  portion  that  the  fol- 
lowing geological  descriptions  more  especially  relate. 

THE    COUNTRY-ROCKS. 

The  rocks  of  this  belt  resemble  in  many  respects  those  already  de- 
scribed under  the  South  mountain  belt  in  North  Carolina.  They  are 
Archaean  micaceous  and  hornblendic  gneisses  and  schists,  which  probably 
represent  sheared  granitic  and  dioritic  rocks.  At  the  Murray  mill,  on 
Yahoola  creek,  near  Dahlonega,  a  large  mass  of  unsheared  granite 
may  be  seen;  and  massive  granite  is  reported  to  exist  on  Yonah  Peak, 
near  Nacoochee.  These  gneisses  and  schists  are  banded  in  narrow., 
lenticular-shaped  layers,  from  2  to  20  feet  wide.  A  dark-colored,, 
schistose  hornblende  rock,  locally  known  as  "  brick-bat,"  is  of  frequent 
occurrence.  Its  structural  relations  are  very  difficult  to  determine;  at 
times  it  is  conformably  interlaminated  with  the  other  schists  (as  at  the 
Hedwig  mine,  near  Auraria);  again,  it  appears  to  have  no  regular  rela- 
tion in  its  position  to  the  adjoining  schists,  which  are  cut  off  by  it  or 
very  markedly  disturbed  in  their  strike,  bending  around  the  "  brick- 
bat "  mass,  and  developing  a  crumpled  or  folded  structure  in  the  schis- 
tose laminae  (as  at  the  Singleton  and  Lockhart  mines,  near  Dahlonega). 
It  is  possible  that  these  "  brick-bat "  masses,  which  appear  to  be  dioritic 
in  origin,  are  magmatic  segregations  or  blebs,  similar  to  the  pyroxemV 
and  hornblendic  blebs  described  in  the  South  Mountain  region,1  though, 
as  a  rule,  larger.  The  prevailing  strike  of  the  gneisses  and  schists  is 
N.  20°-30°  E.,  and  the  dip  30°-60°  S.E.  Locally,  however,  in  the 
presence  of  the  dioritic  masses,  as  explained  above,  this  changes  to 
northwest  strikes  with  northeast  dips.  The  rocks  are  often  garnet- 
iferous  and  contain  rarer  accessory  minerals,  such  as  monazite,    though 

1  See  page  18,  above,  and  Bull.  3,  North  Carolina  Geological  Survey,  1896,  p.  157. 

2  At  the  Glades  Post-Office,  in  Hall  county,  10  miles  northeast  of  Gainesville,  monazite  has 
been  found  in  some  quantity. 


99 


GOLD    MINING    IN    GEORGIA. 


to  a  much  lesser  degree  than  in  the  South  mountain  rocks.  The  depth 
of  the  saprolites  in  the  Georgia  belt  reaches  a  maximum  of  about  100 
feet. 

Diabase'  dikes,  such  as  are  common  in  the  Carolina  belt,  are  not 
found  in  the  Georgia  belt.  Granitic  dikes  are,  however,  not  uncommon 
in  the  Nacoochee  region. 


Fig.  2. — Cross-section  in  Opening  at  Thompson  mine,  near  Nacooehee,  Ga.     Scale, 
1  inch=2  feet,     a,  quartz;   b,  slate;  c,  granite  dike;  d,  -wall  rock. 

The  accompanying  sketch  (fig.  2)  represents  a  small  pegmatite  dike 
at  the  Thompson  mine,  4  miles  west  of  Nacooehee,  showing  the  develop- 
ment of  normal  faulting.  Similar  granitic  dikes  have  been  found  in 
Cherokee  county,  near  the  Franklin  mine.  In  the  Dahlonega  district, 
although  no  unquestionable  well-marked  dikes  are  seen  in  place,  Mr. 
Becker 1  calls  attention  to  the  possibility  that  some  of  the  unusually 
sharply  marked  sheets  in  the  gneiss  might  be  intrusive. 

THE    ORE    DEPOSITS. 

Certain  bands  of  the  gneisses  and  schists  have  been  fissured  and  filled 
with  gold-bearing   quartz   and  sulphurets.     These   fissures   are   in   the 


14'Reconnoissance  of  the  Gold  Fields  of  the  Southern  Appalachians,"  Sixteenth  Annual  Ei 
port  of  the  U.  S.  Geological  Survey,  1894-5,  part  iii,  p.  296. 


GEOGRAPHICAL    AND    GEOLOGICAL    DESCRIPTION    OF    GOLD    BELTS.        23 

main  parallel  to  the  schistosity  of  the  rock,  though  not  uncommonly 
they  cut  the  same  at  low  angles.  To  a  large  extent  they  are  aggre- 
gated in  a  zone  of  numerous  narrow  and  discontinuous  lenses  and 
stringers  through  more  or  less  definite  bands  of  the  gneiss,  which,  taken 
altogether,  form  the  vein.  This  is  well  illustrated  in  Fig.  2.  Mr. 
Becker  has  designated  such  a  system,  a  "  stringer-lead."  In  these 
narrow,  sharply-banded  gneisses  and  schists  of  different  material,  such 
as  they  are  in  this  part  cf  the  Georgia  belt,  it  is  natural  that  the  frac- 
turing force,  once  exerted  in  a  certain  band,  should  have  been  more  or 
less  confined  to  this  one,  both  longitudinally  and  transversely,  the  walls 
of  the  band  forming  the  walls  of  the  ore-body.  This  is  in  fact  the 
case.  At  times  the  Assuring  is  confined  to  the  light-colored  mica- 
gneisses,  at  other  times  to  the  dark-colored  ferromagnesian  gneisses  and 
schists.  The  "  brick-bat  "  schists  rarely  contain  ore-bodies.  The  thick- 
ness of  the  veins  is  from  less  than  3  to  as  much  as  20  feet;  they  are 
frequently  close  together,  separated  by  non-auriferous  bands  of  gneiss; 
and  the  total  width  of  the  ore-bearing  ground  reaches  as  much  as  200 
feet  (Singleton  mine,  Dahlonega).  The  extent  of  fissuring  must  de- 
pend largely  on  the  degree  of  homogeneity  of  the  material,  as  well  as 
on  the  intensity  of  the  fracturing  force.  Where  the  rock  is  of  homo- 
geneous composition  and  the  force  uniformly  exerted,  the  effect  would 
be  a  more  or  less  evenly  distributed  shattering,  with  few  gaping  fis- 
sures, and  the  whole  mass  would  be  permeated  by  the  gold-bearing 
solutions,  with  the  formation  of  auriferous  and  pyritic  impregnations, 
with  some  small  quartz-stringers.  At  the  Hedwig  mine,  near  Auraria, 
for  instance,  regular  quartz  masses  of  any  size  are  altogether  absent, 
the  ore-body  being  composed  of  soft,  sandy,  mica-gneisses  and  -schists 
containing  only  a  few,  small  and  isolated  quartz-stringers.  Again,  under 
different  conditions,  the  effect  was  the  production  of  a  large  number 
of  small  open  fissures,  inducing  the  consequent  formation  of  numerous 
small  lenticular  quartz-stringers;  and  such  is  the  usual  case  in  the 
Dahlonega  ore-bodies  (fig.  2,  p.  22).  Or,  where  the  rock  mass  was  of 
still  greater  heterogeneity,  and  the  forces  of  greater  or  more  varied 
intensity,  lenticular  fissures  have  been  opened,  of  such  size  and  extent 
as  to  allow  a  more  or  less  complete  filling  by  solid  auriferous  and  pyritic 
■quartz,  from  3  to  14  feet  in  thickness;  while,  further  along  the  strike, 
though  the  fracturing  extends  to  the  same  width  and  the  walls  hold  out, 
the  intervening  space  of  country  has  simply  been  shattered,  or  opened 
only  in  small  spaces,  but  was  nevertheless  filled  with  pyritic  impregna- 
tions and  quartz-stringers,  (as  at  the  Franklin  mine  in  Cherokee  county, 
where  these  barren  portions  of  the  vein  are  called  horses).     But  the 

144  Reconnoissance  of  the  Gold  Fields  of  the  Southern  Appalachians,'"  Sixteenth  Annual  Re- 
port of  the  TJ.  S.  Geological  Survey,  1894-5,  part  iii,  p.  283. 


24  GOLD    MINING    IN    GEORGIA. 

leads  are  continuous,  usually  for  considerable  distances.  At  the  Lock- 
hart  mine,  near  Dahlonega,  for  instance,  the  Blackmore  vein,  3  to  6 
feet  in  thickness,  has  been  opened  by  a  drift  400  feet  long.  At  the 
Franklin  mine,  in  Cherokee  county,  the  ore-body  has  been  explored  by 
underground  workings  for  1000  feet,  and  the  continuity  of  the  vein 
has  been  traced  for  three-quarters  of  a  mile  by  isolated  shafts.  The 
regularity  of  the  vein  structure  at  the  Franklin  is  exhibited  by  well- 
defined  walls,  and  by  the  presence  of  a  soft  "  gouge  "  on  both  the  foot 
and  hanging,  even  where  there  is  no  marked  quartz  filling. 

Small,  clean-cut  cross-fissures  occur  in  the  Georgia  belt,  as  at  the 
Franklin  mine,  where  the  filling  is  chiefly  calcite. 

The  pitch  of  the  ore-bodies  in  the  Georgia  belt  is  as  a  rule  to  the 
northeast.  The  filling  of  the  fissures  is  quartz,  carrying  pyrite  and 
rarely  chalcopyrite.  Among  the  most  interesting  gangue  minerals  may 
be  mentioned  garnets,  which  in  cases  have  been  found  to  be  auriferous.1 
Another  occasional,  though  rare,  gangue  mineral  is  tourmaline.  Gold 
in  close  association  with  a  tellurium  mineral  has  been  found  in  the 
so-called  "  Boly  Fields  "  vein  on  the  banks  of  the  Chestatee  river.2  The 
character  of  the  quartz  varies  greatly,  from  very  saccharoidal  to  ex- 
tremely vitreous  types,  and  from  clear  transparent  to  milky-white  in 
color,  sometimes  smoky. 

The  genesis  of  the  ore  deposits  is  best  explained  by  the  ascension 
theory;  there  is  no  evidence  of  substitution.  The  formation  of  the  ore 
deposits  was  subsequent  to  the  force  that  sheared  the  country-rock,  from 
the  fact  that  fragments  of  the  schistose  country  occur  in  the  quartz. 

The  character  of  the  gravel  placer  deposits  in  the  Georgia  belt  is 
similar  to  that  in  the  South  Mountain  belt. 

THE    CAROLINA    BELT    IX    GEORGIA. 

Mention  has  already  been  made  (p.  15)  of  the  extension  of  the  Caro- 
lina belt  into  Wilkes,  McDufrie  and  adjacent  counties,  Georgia. 

MINOR    BELTS    IX    GEORGIA. 

The  crystalline  rocks  of  Georgia  are  comprised  in  the  large  area  lyings 
north  of  a  straight  line  drawn  from  Augusta  to  Columbus.  Within  this 
area  there  are,  besides  the  principal  gold-ore  belts  mentioned  above,  a 
large  number  of  minor  belts;  in  fact,  almost  every  county  in  the  region 
claims  some  discovery  of  the  precious  metal.  Among  the  more  impor- 
tant are  a  belt  including  portions  of  Gwinnett,  Milton,  DeKalb,  Fulton. 
Campbell,   Fayette,   Coweta,   Meriwether  and   Troup   counties:   and  a 

"Reconnoissance  of  the  Gold  Fields  of  the  Southern  Appalachians."  Sixteenth  Annual  Re- 
port of  the  77.  S.  Geological  Survey,  1894-5,  part  iii,  pp.  279,  297. 
2  See  paper  by  Dr.  Wra.  P.  Blake,  Trans.  Am.  Inst.  Min.  Eng„  Vol.  xxv,  1896,  p.  802. 


4 


GEOGRAPHICAL    AND    GEOLOGICAL    DESCRIPTION    OF    GOLD    BELTS.        ZO 

small  belt  lying  on  the  northwest  side  of  the  main  Blue  Ridge  divide, 
in  Towns,  Union  and  Fannin  counties,  extending  into  Clay  county,  ~N.  C. 


7.    THE   ALABAMA   BELT. 

The  Alabama  belt  might  be  considered  a  continuation  of  the  Georgia 
belt.  However,  principally  as  a  matter  of  convenience  for  reference, 
it  is  spoken  of  and  described  separately  here.  It  comprises  an  area  of 
about  3500  square  miles,  situated  in  the  crystalline  rocks  of  Cleburne, 
Randolph,  Talladega,  Clay,  Tallapoosa,  Chambers,  Coosa,  Elmore  and 
Chilton  counties.  This  is  the  southwest  extremity  of  the  southern 
Appalachian  gold  field. 

On  the  latest  geological  map  of  Alabama,1  the  gold-bearing  rocks  of 
this  area  are  distinguished  as:  1.  The  semi-crystalline  Talladega  shales 
of  Algonkian  age,  including  argillaceous  and  hard,  greenish,  sandy 
shales  (often  graphitic);  2.  The  crystalline  schists  of  Archaean  age,  in- 
cluding mica-schists,  which,  on  the  one  hand,  grade  through  gneisses 
into  granite,  and,  on  the  other,  into  siliceous  schists;  garnetiferous  horn- 
blende-schists, probably  of  dioritic  origin,  also  occur.  The  general 
strike  is  KE.  and  the  dip  S.E. 

The  quartz-veins  are  interlaminated  in  these  rocks,  coinciding  imper- 
fectly with  the  dip  and  strike  of  the  schistosity.  Erom  a  structural 
geological  standpoint,  the  veins  bear  much  similarity  to  those  of  the 
Dahlonega  type.  From  a  mining  standpoint,  however,  they  are  dif- 
ferent, not  forming  the  wide  belts  of  numerous  parallel  leads,  as  in 
Dahlonega.  The  quartz  is  usually  glassy;  the  sulphurets  are  in  the 
main  pyritic,  and  the  gangue  minerals  are  those  of  usual  occurrence  in 
gold-bearing  quartz-veins  elsewhere.  The  character  of  the  placer  de- 
posits presents  no  novel  features. 

1  Geological  Map  of  Alabama,  with  Explanatory  Chart,  Geological  Survey  of  Alabama,  1894. 


CHAPTER  II. 

HISTOKICAL  NOTES:  MINING,  METALLURGICAL  AND 

STATISTICAL.1 

EARLY  DISCOVERIES  OF  GOLD  IN  THE  SOUTH   APPALACHIAN 

REGION. 

For  an  account  of  probably  the  earliest  discoveries  of  gold  in  the 
southern  part  of  what  is  now  the  United  States  by  the  Spanish  ex- 
plorers we  refer  the  reader  to  Mr.  G.  E.  Becker's  paper,  Beconnoissance 
•of  the  Gold  Fields  of  the  Southern  Appalachians.2 

Reports  of  the  existence  of  gold  in  the  Southern  States  antedate  the 
time  of  the  Revolutionary  war,  as  for  instance,  in  South  Carolina  at 
the  Brewer  mine  in  Chesterfield  county,  and  in  North  Carolina  at  the 
Oliver  mine  in  Gaston  county,  the  Dunn  mine  in  Mecklenburg  county, 
and  the  Parker  mine  in  Cherokee  county. 

However,  no  absolutely  authentic  references  to  these  can  be  obtained, 
and  the  date  of  the  first  actual  discovery  of  gold  in  this  country  must 
Temain  shrouded  in  uncertainty. 

Jefferson,  in  his  Notes  on  Virginia  (1782),  mentions  the  discovery  of 
.a  nugget  containing  17  dwts.  "of  gold  four  miles  below  the  falls  of  the 
Rappahannock  river.  The  U.  S.  Mint  reports  give  the  first  returns  from 
Virginia  in  1829.  For  North  Carolina  the  first  mint  returns  appear  in 
1793;  but  the  first  mention  of  any  specific  find  of  gold  in  North  Caro- 
lina is  of  a  17-pound  nugget,  discovered  on  the  Reed  plantation  in 
Cabarrus  county,  in  1799. 

Mills,  in  his  Statistics  of  South  Carolina,  notes  the  occurrence  of 
gold  in  Abbeville  and  Spartanburg  districts  as  early  as  1826,  but  the 
first  U.  S.  mint  returns  from  this  State  are  given  in  1S29. 

The  gold  placers  in  Burke  and  McDowell  counties,  North  Carolina, 
(South  Mountain  belt)  were  first  worked  in  1829,  and  immediately 
traced  southwestward  through  South  Carolina  into  Georgia. 

John  Witheroods,  of  North  Carolina,  claims  to  have  first  discovered 
gold  in  Georgia  in  1829  at  Duke's  creek,  near  Nacoochee,  Habersham 
county;3  but  Jesse  Hogan,  also  of  North  Carolina,  claims  to  have  taken 

1  We  are  indebted  to  Mr.  Geo.  R.  Hanna,  of  the  Charlotte  Assay  office,  for  valuable  notes  re 
lating  to  the  History  of  Mining  and  Metal] urg-ical  Operations  in  North  Carolina. 

2  Sixteenth  Annual  Report  of  the  77.  S.  Geological  Survey,  part  iii,  1894-5. 

3  Now  in  White  county,  which  was  later  formed  from  a  part  of  Habersham. 


3  feibrarifi 


HISTORICAL    NOTES :    MINING,    METALLURGICAL    AND    STATISTICAL.        2  < 

out  gold  previously  in  a  branch  of  Ward's  creek  near  Dahlonega,  which 
was  then  in  the  "  Cherokee  Nation."  The  earliest  mint  returns  from 
Georgia  appear  in  1830. 

Dr.  Wm.  B.  Phillips *  gives  1830  as  the  probable  approximate  date 
of  the  first  discovery  of  gold  in  Alabama.  There  were,  however,  no 
mint  returns  from  this  State  until  1840. 

Perhaps  one  of  the  chief  reasons  that  the  discovery  of  gold  came 
so  much  later  in  Georgia  and  Alabama  than  it  did  in  North  Carolina 
and  Virginia,  was  that  this  part  of  the  country  was  then  occupied  by 
the  Cherokee  Indian  Nation,  under  the  supervision  of  the  United  States, 
and  was  not  open  to  white  settlers,  although  the  latter  repeatedly  in- 
truded. 

After  the  discovery  of  gold,  the  long  pending  efforts  of  the  States 
to  acquire  these  Indian  lands  were  stimulated  and  accelerated  by  the 
added  thirst  for  the  precious  metal,  and  were  finally  successful  in  1830, 
when  the  State  laws  were  extended  over  the  Nation  and  the  Indians 
were  removed.  The  mining  region  in  Georgia  was  surveyed  into  40-acre 
lots,  which  were  distributed  by  lottery.  A  caustic  writer  of  the  time 
says  that,  "  intrusive  mining  ceased  then  and  there,  and  swindling  min- 
ing commenced." 

The  first  mention  of  gold  in  Tennessee  is  from  Coco  creek,  Monroe 
county,  in  1831,2  and  this  date  corresponds  with  that  of  the  first  mint 
receipts. 

The  earliest  record  of  gold  in  Maryland  is  in  1849,3  from  the  farm  of 
Mr.  Samuel  Ellicott  in  Montgomery  county,  about  12  miles  north  of 
Washington,  where  a  depth  of  50  feet  was  said  to  have  been  reached, 
and  about  $3000  in  gold  to  have  been  taken  out.  The  mint  reports, 
however,  show  no  returns  previous  to  1868. 

EARLY   MINING   OPERATIONS. 

The  greatest  activity  of  gold  mining  in  the  South  seems  to  have  fol- 
lowed closely  on  the  first  discovery,  being  most  marked  from  1829  to 
1836,  and  probably  due  to  the  working  of  the  more  accessible  virgin 
placers  and  more  easily  mined  outcrops.  The  mint  receipts  show  a 
renewed  activity  from  1839  to  1849,  caused  perhaps  by  more  syste- 
matic vein  explorations  and  improved  methods.  In  the  early  fifties,  the 
Californian  discoveries  abated  the  interest  in  the  Southern  gold  field,  and 
attracted  the  mining  population  westward,  causing  a  natural  depression 
in  the  output;  from  that  time  on  there  was  a  general  decrease  until  the 

1  Geological  Survey  of  Ala.,  Bull.  No.  3, 1892,  p.  10. 

2  Safford's  Geology  of  Tenn.,  1869,  p.  490. 

3  Emmons,  E.,  Proceedings  of  the  American  Philosophical  Society,  1849,  Vol.  v.,  p.  85;  see  also 
Am.  Jour.  Sci.,  Vol.  xvii,  1830,  p.  202. 


L',S  GOLD    MINING    IN    NORTH    CAROLINA. 

practically  total  cessation  caused  "by  the  Civil  "War.  Since  then  there 
have  been  spasmodic  revivals  and  depressions,  due  undoubtedly  in  a 
great  measure  to  local  causes  and  excitements,  and  to  the  financial  con- 
dition of  the  country  at  large.  Considering  the  small  total  output  of 
the  South,  such  fluctuations  may  have  been  caused  by  the  successful 
working  of  a  single  mine,  shown  for  instance,  by  the  increased  produc- 
tion of  South  Carolina  since  1890,  owing  to  the  revival  of  the  Haile 
mine. 

The  first  practical,  systematic  mining  operations  appear  to  have  been 
in  North  Carolina,  beginning  about  the  year  1800.  Prom  1804  to 
1827  (inclusive)  this  State  furnished  all  of  the  gold  produced  in  the 
country,  amounting  to  $110,000.  The  progress  up  to  1820  was  very 
slow,  and  mining  was  restricted  to  a  very  limited  area.  Prof.  Olrn- 
stead,  the  first  State  Geologist  of  North  Carolina,  in  his  writings,1  esti- 
mated the  extent  of  the  then  known  gold  country  at  1000  square  miles. 
He  says:  "  The  gold  country  is  spread  over  a  space  of  not  less  than  1000 
square  miles.  With  a  map  of  North  Carolina,  one  may  easily  trace 
its  boundaries,  so  far  as  they  have  been  hitherto  observed.  From  a 
point  taken  eight  miles  west  by  south  of  the  mouth  of  the  Uwharie, 
with  a  radius  of  eighteen  miles,  describe  a  circle;  it  will  include  the 
greatest  part  of  the  county  of  Montgomery,  the  northern  part  of  Anson, 
the  northeastern  corner  of  Mecklenburg,  Cabarrus — a  little  beyond 
Concord  on  the  west — and  a  corner  of  Rowan,  and  of  Randolph.  In 
almost  every  part  of  this  region  gold  may  be  found  in  greater  or  less 
abundance  at  or  near  the  surface  of  the  ground.  Its  true  bed,  how- 
ever, is  a  thin  stratum  of  gravel  enclosed  in  a  dense  mud,  usually  of  a 
pale  blue,  but  sometimes  of  a  yellowish  color.  .  .  .  Rocky  river  and  its 
small  tributaries,  which  cut  through  this  stratum,  have  hitherto  proved 
the  most  fruitful  localities  of  the  precious  metals." 

In  1820  articles  began  to  appear  in  the  public  journals  calling  atten- 
tion to  the  North  Carolina  gold  deposits,  and  itinerant  German  miners 
and  mineralogists  had  already  come  into  the  country  in  some  number. 

In  1821,  when  Olmstead  wrote,  there  was  a  considerable  mining  popu- 
lation, whose  average  earnings  were  from  60  to  65  cents  per  day 
(approximately  65  to  70  cents  in  the  present  standard  of  gold  coinage). 
The  toll  paid  to  the  owners  of  the  land  varied  from  one-fourth  to  occa- 
sionally one-half  of  the  yield.  The  dust  came  to  Be  quite  a  medium  of 
circulation,  and  miners  were  accustomed  to  carry  about  with  them  quills 
filled  with  gold,  and  a  pair  of  small  hand-scales,  on  which  they  weighed 
out  gold  at  regular  rates,  (for  instance,  3^  grains  of  gold  was  the  cus- 
tomary equivalent  of  a  pint  of  whiskey).     The  gold  found  its  way  largely 

1Am.  Jour.  ScL,  1825. 


I 


HISTORICAL    NOTES!    MINING,    METALLURGICAL    AND    STATISTICAL.         29 

into  the  country  stores  in  exchange  for  merchandise  at  the  rate  of  90 
to  91  cents  per  pennyweight  (96  to  97  cents  present  standard). 

In  these  early  days  farming  and  gold  digging  went,  in  many  cases, 
hand  in  hand;  and  this  is  indeed  still  true,  to  some  extent,  at  the  present 
day.  When  the  crops  were  laid  by,  the  slaves  and  farm  hands  were 
turned  into  the  creek-bottoms,  thus  utilizing  their  time  during  the  dull 
seasons.  Where  mining  proved  more  profitable  than  planting,  the  for- 
mer superseded  the  latter  entirely.  Thus,  in  speaking  of  the  Tinder 
Mats  placer  in  Louisa  county,  Va.,  Silliman  says:1 

"  Jenkins  is  in  the  habit  of  substituting  a  fall  working  in  the  gold, 
for  which  he  obtains  $1000  annually,  as  a  compensation  for  his  tobacco 
crop,  which  he  relinquishes  in  favor  of  the  gold." 

Some  of  the  more  prominent  localities  developed  into  regular  mining 
camps,  where  continuous  and  extensive  operations  were  carried  on. 
Such  were,  for  instance,  Arbacoochee  and  Goldville,  Ala.;  Auraria  and 
Dahlonega,  Ga.;  and  Gold  Hill  and  Brindletown,  ~N.  C.  In  the  latter 
place  it  is  stated  that  just  before  the  California  excitement  as  many 
as  3000  hands  might  have  been  seen  at  work  on  one  of  the  streams  of 
the  region.'2  In  1853  there  was  a  population  of  about  2000  in  the  Gold 
Hill  camp. 

When  Lumpkin  county,  Ga.,  was  organized  in  1832,  Dahlonega  (then 
called  New  Mexico)  had  a  population  of  800.  During  the  mining 
boom  Dahlonega  had  a  population  of  5000,  and  Auraria  (then  called 
Knucklesville)  2000  to  3000.3 

At  Goldville,  Ala.,  between  1840  and  1850,  there  was  a  population 
of  at  least  3000. 

The  first  work,  naturally,  was  the  washing  of  the  stream  placers. 
After  these  were  exhausted,  attention  was  turned  to  the  gravel  deposits 
lying  under  cover  of  the  alluvium.  These  were  Avorked  by  sinking  pits, 
and  raising  the  gravel  by  hand  labor.  Where  it  was  necessary  the 
pits  were  drained  by  large  vertical  bucket-wheels,  for  which  the  power 
was  derived  from  the  stream  directly,  or  by  flume  lines  with  over-shot 
or  under-shot  wheels. 

EARLY   MINING   AND   METALLURGICAL   METHODS. 

The  first  primitive  washing,  as  in  other  newly  discovered  gold  coun- 
tries, was  probably  done  with  the  pan.  As  the  workings  grew  more 
extensive,  this  was  superseded  by  the  rocker,  long  torn  and  sluice-box; 
and,  indeed,  these  original  devices  survive  to  the  present  day. 

1Eeport  to  the  President  and  Directors  of  the  Walton  Mining  Company.    By  Prof.  B.  Silliman, 
Jr.,  Fredericksburg-,  Va.,  1836. 

2  Ores  of  North  Carolina,  1887,  p.  312. 

3  Recollections  of  A.  G.  Wimpy  (a  very  old  citizen  of  Dahlonega,  Ga.)  published  in  the  Dah- 
lonega Signal,  Aug.  20,  1883. 


30  GOLD    MINING    IN    NORTH    CAROLINA. 

The  rockers  in  use  to-day  are  of  two  types.  The  first  is  essentially 
a  panning  process,  nsing  a  minimum  amount  of  water,  the  operation 
being  an  intermittent  one.  This  type  of  rocker  is  closed  at  both  ends, 
the  discharge  being  over  the  side;  it  will  be  described,  with  illustrations, 
as  now  in  use  at  the  Crawford  mine  (p.  94).  The  second  type  con- 
sists of  a  hollow  segment  of  a  log  closed  at  the  upper  end.  It  is  set 
on  a  slight  inclination,  about  6  inches  in  10  feet,  and  is  provided  at  the 
lower  end  with  grooves  or  strips  that  act  as  mercury  pockets  or  riffles. 
When  used  on  gravel  it  is  provided  at  the  upper  end  with  a  shallow 
box  having  a  round  punched  or  slotted  iron  bottom.  The  length  of 
this  type  of  rocker  is  5  to  10  feet.  The  gravel  and  clay  are  thrown 
into  the  box,  where  a  constant  stream  of  water,  together  with  the  rock- 
ing motion  and  stirring  with  fork  or  shovel,  disintegrates  the  material. 
The  pebbles  and  bowlders  are  thrown  out  with  the  fork,  while  the  fine 
portions  are  washed  down  the  bottom.  The  rocking  facilitates  the 
settling  and  amalgamation  of  the  gold  and  the  discharge  of  the  tailings. 
Two  men  work  at  one  rocker  or  set  of  rockers,  so  joined  together  as  to 
move  in  harmony.  One  throws  the  gravel  from  the  pit  into  the  box,, 
or  directly  into  the  rockers,  and  the  other  sits  or  stands  above  the  rock- 
ers moving  them  with  his  feet,  disintegrating  the  gravel  with  a  fork 
and  discharging  the  coarse  material.  Rockers  of  a  similar  type  are  at 
present  in  use  at  several  mills  for  handling  pulp  and  blanket  washings. 
(See  Plate  I.) 

AVhere  sufficient  flowing  water  is  at  hand,  the  sluice  box  and  long 
torn  are  used,  as  they  handle  larger  quantities  with  less  labor.  The 
sluice  box,  generally  8  to  10  feet  long,  20  inches  wide  and  12  inches 
deep,  provided  with  riffles  and  a  perforated  charging  plate  at  the  head, 
fulfils  the  same  purpose  as  the  rocker;  being  stationary,  however,  it 
requires  a  larger  amount  of  water  to  carry  off  the  tailings. 

It  is  interesting  to  note  that  at  the  Beaver  Dam  mine,  in  Mont- 
gomery county,  N".  C,  a  large  rocker,  about  10  feet  long  by  3  feet  wide,. 
was  operated  as  early  as  1825  by  steam  power,  the  engine  having  been 
imported  from  England. 

Tuomey,1  in  1854,  mentions  ground-sluicing  of  side-hill  deposits  at 
Arbacoochee,  Ala.,  by  aid  of  a  ditch  and  a  series  of  trenches  into  which 
quicksilver  was  poured.  It  is  probable  that  this  method  of  working 
existed  even  prior  to  that  day. 

HYDRAULIC    METHODS. 

The  first  use  of  the  hydraulic  method  of  mining  was  probably  early 
in  the  forties,  previous  to  the  California  gold  discoveries,  in  the  west- 
ern part  of  Xorth  Carolina,  although  on  a  much  smaller  and  modified 

1  Second  Biennial  Report  on  the  Geology  of  Alabama,  p.  70,  Montgomery,  185$. 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  10,  PLATE  I. 

1F7~ 


LOG  ROCKERS,  GOLD   HILL,  N.   C. 

A  small  stream  of  water  pours  from  the  crude  V-shaped  trough  above  into  the  upper  end  of  each 

of  the  larger  troughs  below,  and  washes  the  gravel  and  soil  out  at  their  lower  ends. 

'See  also  p.  60.) 


CHILIAN    DRAG-MILL   AND   ROCKERS,   NEAR   GOLD  HILL,    N.   C. 
(See  page  33.) 


II 


HISTORICAL    NOTES!    MINING,    METALLURGICAL    AND    STATISTICAL.         31 

scale  as  compared  to  its  present  application.  Mr.  Wm.  H.  Ellet,  writ- 
ing in  the  Mining  and  Statistic  Magazine  1  early  in  1858,  in  reply  to 
Hon.  T.  L.  Clingman's  inquiry  of  December,  1857,  says: 

"  I  avail  myself  of  my  earliest  leisure  to  answer  your  inquiries  in  relation  to 
the  hydraulic  gold-mining  operations  lately  introduced  by  Dr.  M.  H.  Vandyke, 

in  some  of  the  western  counties  of  North  Carolina My  observations  in  the 

hydraulic  process  were  made  during  the  month  of  April 3  at  the  Jamestown 
mine,3  in  McDowell  county,  N.  C.     The  water  was  there  conveyed  ....  about  4 

miles.     The  uniform  descent  was  4  inches  to  the  hundred  feet The  number 

of  hose  pipes  employed  was  four.  The  mass  of  earth  moved  in  nine  working 
days  was  20  feet  in  depth,  82  in  length  and  26  in  breadth,  being  at  the  rate 

of   1184  cubic   feet,   or  966  bushels,   per  day   for   each   hose The   labor 

employed  ....  was  that  of  four  men  and  two  boys The  yield  in  gold 

was  $5.13  per  day  for  each  hose  employed. 

Shortly  afterwards  a  further  publication  appeared  in  the  same  mag- 
azine,4 from  which  the  following  extracts  are  taken: 

"  The  Wilkinson  gold  mine  in  Burke  county,  N.  C,  is  owned  by  Dr.  Van  Dyke, 
and  is   worked  by  the  hydraulic   process.     The   water  is   brought  ....  by   a 

canal  or  aqueduct  for  a  distance  of  15  miles The  water  is  not  brought 

upon  these  mines  at  a  very  high  head,  only  about  40  feet.  There  was  only  one 
pipe  in  operation  at  the  time  of  my  visit.     The  water  passed  through  a  6-inch 

hose  and  a  nozzle  of  iy2  inches The  average  yield  of  the  mine  ....  was 

about  $5.00  a  day  to  each  hand Obtaining  a  sample  of  the  gold  of  this 

mine,  we  passed  over  about  2  miles  to  the  Bunker  Hill  mine,  also  in  Burke 
county.     This  was  formerly  known  as  the  Brindleton  mine.     It  is  owned  and 

worked  by  Rev.  Benjamin  Hamilton It  is  now  worked  by  the  hydraulic 

process T>      amount  of  water  is  limited,  sufficient  only  for  about  two 

pipes,  which  is  brought  in  a  small  ditch  for  a  distance  of  4  or  5  miles 

The  Collins  mine  in  Rutherford  county  is  owned  and  worked  by  Dr.  Van 
Dyke.  The  water  is  brought  to  this  mine  in  a  canal  about  4  miles  in  length, 
at  an  elevation  of  150  feet,   and   sufficient  in  amount  for  20  pipes,   and  will 

command    nearly    1000    acres    of    surface Jamestown    mine,    McDowell 

county,  N.  C,  [is]  also  worked  by  Dr.  Van  Dyke.  The  deposit  workings  embrace 
about  400  acres.  The  water  is  brought  by  a  canal  at  an  elevation  of  70  feetr 
and  is  five  miles  in  length.     There  is  water  enough  here  for  20  hose  pipes." 

Prof.  Wm.  P.  Blake  (in  1858)  in  a  "  Keport  upon  the  Gold  Placers  of 
Lumpkin  county,  Georgia,  and  the  Practicability  of  Working  them  by 
the  Hydraulic  Method,  with  Water  from  the  Chestatee  River,"5  says: 

"  Desiring  to  see  the  results  obtained  [by  Dr.  M.  H.  Van  Dyke]  in  North 
Carolina,  and  thus  to  be  enabled  to  form  a  better  judgment  of  the  probable 
results  in  Georgia,  I  first  visited  the  placers  in  Burke  and  McDowell  counties 


1  Vol.  x,  pp.  27-30,  January  1858.    Our  attention  was  called  to  this  and  related  articles  by  the 
interesting-  paper  of  Prof.  Wm.  P.  Blake,  published  in  the  Transactions  of  the  America)!  F»sti- 
tute  of  Mining  Engineers,  October  1895,  entitled  Notes  and  Recollections  Concerning  tli<-  Min 
eral  Resources  of  Northern  Georgia  and  Western  North  Carolina. 

- 1857. 

3  Afterwards  and  at  present  known  as  the  Vein  Mountain  mine. 

4  Vol.  x,  pp.  393,  394,  May,  1858. 

5  Mining  and  Statistic  Magazine,  vol.  x,  pp.  457-476,  June,  1858. 


32  GOLD    MINING    IN    NORTH    CAROLINA. 

where  the  [hydraulic]  process  is  now  in  successful  operation The  average 

yield,  as  shown  by  the  results  at  several  of  the  North  Carolina  placers,  is  about 
$6.00  a  day   to  a  pipe  attended   by  two  men,  or  by  a   man  and  a  boy.     At 

some  of  the  placers  the  average  is  not  less  than  §10.00  a  day At  Brin- 

dletown,  in  the  bed  of  a  little  brook  which  has  a  rapid  descent,  Mr.  Hamilton 

has  been  washing  very  successfully  with  two  pipes  and  five  men  and  boys 

I  am  confident  that  the  yield  cannot  be  less  than  $20.00  a  day,  even  among 
the  former  excavations  where  the  gravel  has  been  washed  over  more  than 
once  before." 

Lieber1  mentions  the  hydraulic  process  as  being  practiced  previous 
to  1859  at  Pilot  mountain  in  Burke  County,  X.  C,  and  he  evidently 
has  reference  to  the  above  described  localities. 

The  Dahlonega  method  (a  combination  of  hydraulicking,  sluicing  and 
milling)  originated  in  1868. 

The  first  record  that  we  have  of  dredge  mining  is  that  carried  on  by 
a  Mr.  Gibson  in  1843-4,  in  the  Catawba  river,  Gaston  county,  X.  C. 
The  river  sediments  and  gravel  were  scooped  out  on  flatboats  by  men 
using  long-handled  scoops,  and  the  material  was  carried  ashore  and 
washed. 

Later  on  mechanical  dredges  of  various  designs  came  into  use, 
chiefly  on  the  Chestatee  river,  in  Georgia. 

The  advent  of  the  hydraulic  gravel  elevator  dates  from  about  1883. 
It  was  'first  applied  at  Brindletown,  N".  C,  and  at  Dahlonega,  Ga.  The 
well-known  type  of  this  mechanism,  known  as  the  Hendy  lift,  was 
employed  at  the  Cincinnati  Consolidated  Company's  mines  in  Dawson 
county,  Ga.,  in  1SS3.  The  plan  was  to  divert  the  Etowah  river  and 
to  suck  up  the  gravel  from  the  old  channel. 

The  Roy  Stone  method"  was  experimented  with  in  the  Chestatee 
river  in  1883,  but  the  results  are  not  known. 

The  Crandall  hydraulic  elevator,3  as  used  at  the  Chestatee  mine, 
Georgia,  in  1895,  contains  important  improvements  over  other  types  of 
similar  mechanisms. 

VEIN    MINING.      FREE-MILLING   ORES. 

Yein  mining  probably  followed  more  or  less  closely  on  the  exhaus- 
tion of  the  richer  gravel  deposits.  The  first  account  of  vein  mining  is 
in  1825,  at  the  Barringer  mine,  Stanly4  county,  !N\  C.  In  Virginia 
the  veins  of  the  Tellurium  and  Yaucluse  mines  were  discovered  in  1832; 
and  in  Georgia  the  Reynolds  vein,  lot  IsTo.  10,  near  !N"acoochee,  in 
White  county,  was  discovered  some  time  prior  to  1834. 

1  Supplementary  Report  to  the  Survey  of  South  Carolina,  1S59,  p.  154. 

2  Trans.  Amer.  Inst.  Min.  Eng.,  vol.  viii,  p.  254. 

3  Ibid.,  vol.  xxvi,  1897,  pp.  62-68. 

4  This  part  of  Stanly  was  then  a  part  of  Montgomery  county. 


HISTORICAL    NOTES:    MINING,    METALLURGICAL    AND    STATISTICAL.        33 
EARLY    MILLING    APPLIANCES. 

For  a  long  time  the  output  was  confined  to  the  free-milling  brown 
ores  near  the  surface,  and  the  ore  was  raised  by  horse-whim  and  hand- 
windlass,  or  even  by  baskets  carried  upon  the  backs  of  the  miners.  At 
first  the  gold  from  the  ores  of  the  decomposed  outcrops  of  the  veins 
was  extracted  by  washing  in  rockers.  The  following  quotation  from 
Prof.  Elisha  Mitchell's  Report  on  the  Geology  of  North  Carolina  (1827), 
is  pertinent  here : 

"  The  quartz  is  raised  from  the  mine,  broken  to  pieces,  and  those  parts 
which  are  known  to  contain  gold  selected  for  washing.  This  part  of  the 
process  is  conducted  in  the  same  way  as  in  Montgomery  (county),  except  that 
the  agitation  is  continued  for  a  longer  time,  and  that  a  small  quantity  of 
quicksilver  is  put  into  the  rockers  to  collect  the  gold,  by  forming  an  amalgam 
with  it." 

The  most  primitive  method  of  milling  the  quartz  was  undoubtedly 
by  crushing  in  hand-mortars  and  subsequent  panning.  This  is  still 
carried  on  by  the  native  tributors  in  certain  districts.  It  was  followed 
by  the  introduction  of  the  drag  mill  {arr astro),  the  Chilean  mill  (Plate 
I,  p.  30)  and  eventually  the  stamp-mill.  The  two  former  were  evidently 
drawn  from  South  American  and  Mexican  practice,  and  were  probably 
the  first  mechanical  pulverizing  machinery  used. 

As  an  illustration  of  some  of  the  earlier  milling  methods,  the  f ollowT- 
ing  is  taken  from  a  report  of  the  Supervising  Committee  of  the  United 
States  Mining  Company  in  1835,  on  their  mine  near  the  Rappahannock 
river,  Virginia: 

"  The  plant  consists  of  a  crushing  (rolls)  and  a  vertical  mill  (stamping-mill)  in 
a  building  26x36  feet.  Both  mills  are  located  on  the  ground  floor  and  are 
propelled  by  a  water-wheel  11  feet  in  diameter,  with  a  11-foot  face.  The 
crushing-mill  has  3  sets  of  cylinders  2  feet  in  length  and  15  inches  in  diameter, 
the  first  or  upper  set  fluted,  the  other  smooth.  The  ore  is  thrown  into  a  hopper 
on  the  upper  floor,  from  which  it  is  conducted  over  an  inclined  shaking-table 
to  the  fluted  cylinders,  by  which  it  is  crushed  to  a  size  from  14  to  1  inch  in 
diameter.  The  crushed  material  is  equally  divided  and  goes  to  the  two  sets 
of  smooth  cylinders.  By  them  it  is  further  greatly  reduced,  ranging  from 
impalpable  powder  to  grains  as  large  as  coarse  hominy.  From  these  cylinders 
it  falls  into  a  sifter  having  the  fineness  and  motion  of  the  common  meal-sifter, 
from  whence  the  material  which  passes  through  is  conducted  to  12  amalga- 
mators, constructed  upon  the  principle  of  the  Tyrolese  bowls,  making  from  90 
to  100  revolutions  per  minute.  They  perform  the  office  of  washing  and  amalga- 
mating. The  sand  discarded  by  them,  after  being  washed,  is  conducted  through 
troughs  to  the  vertical  mill,  where,  being  reduced  to  an  impalpable  powder,  it 
passes  in  the  shape  of  turbid  or  muddy  water  to  another  set  of  amalgamators 
similar  to  those  above  mentioned,  and  thence  to  the  river.  The  portion  of  the 
ore  reduced  by  the  cylinders  which  passes  over  the  sifters  is  conducted  to  the 
vertical  mill,  and  is  treated  in  the  same  manner." 


34  GOLD    MINING    IN    NORTH    CAROLINA. 

The  process  at  another  Virginia  mine,  the  Vaucluse,  is  described '  in 
1847  as  follows: 

"  The  machinery  consists  of  a  condensing  Cornish  mining  engine  of  120  horse- 
power; the  mill-house  contains  6  large  Chilean  mills;  the  cast-iron  bed-plate  of 
each  is  5  feet  6  inches  in  diameter,  and  on  it  are  two  cast-iron  runners  of  the 
same  diameter,  the  total  weight  of  the  mill  being  6200  pounds.  The  ores,  on 
arriving  at  the  surface,  are  divided  into  two  classes:  1.  The  coarse  and  hard 
ore  for  the  stamps;  2.  Slate  and  fine  ore  for  the  Chilean  mills.  This  is  done  by 
means  of  a  large  screen.  The  very  large  pieces  are  first  broken  by  a  hammer 
before  they  are  fed  to  the  stamps.  All  of  the  ores  are  ground  with  water,  each 
mill  being  supplied  with  hot  and  cold  water  at  pleasure.  Twelve  inches  from 
the  top  of  the  bed-plate  there  is  a  wide,  open  mouth,  from  which  the  turbid 
water  escapes  to  tanks.  On  the  south  side  of  the  steam-engine  is  the  stamp 
house  and  amalgamation  mill,  containing  6  batteries  of  3  stamps  each;  these 
stamps,  with  the  iron  head  of  125  pounds,  weigh  350  to  380  pounds  each.  Each 
battery  is  supplied  with  water,  and  at  each  blow  of  the  stamp  a  portion  of  the 
fine  ore  passes  out  of  the  boxes  through  the  grates  to  the  amalgamation  room. 
Here  are  stationed  18  small  amalgamation  bowls  of  cast  iron.  30  inches  in  diam- 
eter. The  bowls  are  supplied  with  runners  which  move  horizontally:  in  the 
center  of  these  runners  is  an  eye  or  opening  like  that  in  the  runner  of  a  corn- 
mill.  The  ground  or  finely-stamped  ore,  gold  and  water  pass  into  this  eye.  and 
by  the  rotary  motion  of  the  same  are  brought  into  contact  with  the  quicksilver 
deposited  in  the  center,  forming  amalgam.  From  the  amalgamators  the  pulp 
passes  through  3  dolly-tubs  or  catch-alls,  acting  as  mercury  and  gold  tubs.  After 
this  the  whole  mass  passes  to  the  strakes  or  inclined  planes,  where  The  sul- 
phurets  are  deposited  and  the  earthy  matter  washed  away.  These  sulphurets 
were  formerly  treated  in  two  heavy  Mexican  drags  or  arrastras;  but  not  answer- 
ing so  good  a  purpose,  they  have  been  altered  into  three  heavy  Chilean  mills."" 

The  collection  of  amalgam,  retorting  and  melting  was  practically  the 
same  as  to-day.     The  total  plant  at  this  mine  was  valued  at  $70,000. 

Emmons  gives  the  method  of  working  the  ores  of  Gold  Hill,  X.  C.r 
in  the  earlier  days  as  follows : " 

"  The  machinery  employed  at  Gold  Hill  for  separating  gold,  consists,  first  of 
the  Chilean  mill  for  crushing  and  grinding,  after  being  broken  by  hammers, 

the  Tyrolese  bowls,  the  Burke  rockers,  and  the  drag-mill The  work  for 

a  Chilean  mill  of  this  ore  is  70  bushels  per  day,  and  our  mills  run  for  24  hours, 
with  one  or  two  short  interruptions.  They  are  all  moved  by  steam-power,  and 
all  the  water  used  in  the  mills  is  pumped  from  the  mine.  The  Burke  rocker 
is  the  principal  and  best  saving  machine  employed.  The  drag-mill  is  also  a 
good  machine,  is  cheap,  and  easily  kept  in  repair.  On  inspecting  these  opera- 
tions when  going  on  it  is  impossible  to  resist  the  conclusion  that  much  of  the 
gold  is  wasted  along  with  the  mercury." 

Emmons  further  states  the  force  employed  at  Gold  Hill  at  that  time 
for  working  the  Earnhardt  (Randolph)  vein  to  consist  of: 

"  66  miners  paid  by  the  month  and  39  negroes  hired  by  the  year.  The  day 
of  24  hours  is  divided  into  three  shifts  of  eight  hours  each  for  underground 
work." 

1  Plan  and  Description  of  the  Vaucluse  Mine,  Orange  County,  Va.    Philadelphia,  1S47. 

2  Geological  Report  of  the  Midland  Counties  of  North  Carolina,  1S56.  E.  Emmons,  pp.  160et8€9. 


1 


HISTORICAL    NOTES!    MINING,    METALLURGICAL    AND    STATISTICAL.         6b 

The  stamp-mill,  or,  as  it  was  originally  called,  the  "  pounding  mill," 
was  most  probably  a  European  innovation.  As  early  as  1836  a  6-stamp 
mill,  with  50-pound  stamps,  was  in  operation  at  the  Tellurium  mine  in 
Virginia.  In  1837  a  Frenchman  erected  a  mill  at  the  Haile  mine  in 
South  Carolina.  These  primitive  mills  were  constructed  of  wood,  with 
iron  shoes  and  die-plates;  the  general  type  of  construction  was  similar 
to  that  of  the  present  California  mills,  with  the  exception  that  the 
stems  were  square  and  did  not  revolve,  the  cams  working  in  slots  or 
recesses  cut  into  the  stems.  A  few  of  these  old-fashioned  mills  may 
still  be  seen  in  operation  in  Georgia  in  the  Nacoochee  valley,  seemingly 
serving  the  purpose  of  the  tributors  and  petty  quartz  miners,  and  it  is 
stated  that  they  are  operated  at  a  fair  profit.  They  are  cheaply  con- 
structed, a  10-stamp  mill  with  water-wheel  and  building  complete 
costing  about  $150.  The  amalgamation  is  done  on  a  copper  plate  of 
the  width  of  the  battery  and  about  one  foot  long. 

The  first  regular  California  battery  was  erected  at  the  Kings  moun- 
ain  mine,  in  North.  Carolina,  just  after  the  war;  and  in  1866  a  similar 
mill  was  built  at  the  Singleton  mine,  in  Georgia,  by  Dr.  Hamilton. 

Besides  mills  of  "Western  manufacture,  there  are  two  types  which 
are  common  to  the  South.  One  of  these  is  an  excellent  750-pound  mill 
built  by  the  Mecklenburg  Iron  Works  of  Charlotte,  N".  C,  a  slight 
variation  of  the  Western  type  (described  on  p.  119).  The  other  is  the 
450-pound  Hall  mill,  which  is  peculiarly  adapted  to  the  saprolitic  ores 
of  the  Dahlonega  district  in  Georgia  (described  on  pp.  110—113.) 

Various  types  of  rotary  pulverizers  and  pan  amalgamators  have  been 
introduced  in  the  South  from  time  to  time,  supposedly  as  improvements 
on  the  stamp-mill,  as,  for  instance,  the  Tlowland  mill,  a  flat  circular 
disc  revolving  in  an  iron  shell;  and,  similarly,  the  Crawford  (with 
revolving  iron  balls)  and  the  Huntington  mills;  the  Parson  mill,  not 
unlike  the  Howland,  but  covered  with  a  hood,  and  having  the  interior 
grinding  surfaces  coated  with  lead-amalgam;  the  Meech  mill,  in  which 
the  quicksilver  was  comminuted  by  superheated  steam;  the  Wiswell 
mill,  being  practically  an  iron  Chilean  mill  fed  with  corrosive  sub- 
limate in  connection  with  an  electric  current;  the  Nobles  process,  in 
which  the  ore  was  ground  to  100-mesh  between  buhr-stones  and  the 
pulp  run  over  amalgamated  slabs  of  zinc  or  lead.  Revolving  Freiberg 
barrels  were  also  used  at  some  of  the  mines.  The  Blake  system  of  fine 
crushing,  combined  with  subsequent  wet  grinding,1  was  introduced  at 
the  Haile  mine  in  1884,  but  was  soon  abandoned  in  favor  of  the 
present  stamp-mill. 

The  above  are  simply  cited  as  a  few  examples  of  the  vast  number  of 
mechanical  appliances  for  grinding  and  amalgamation  with  which  the 

1  Trans.  Amer.  Inst.  Mining  Evaincers,  vol.  xvi,  p.  7.V>. 


36  GOLD    MINING    IN    NORTH    CAROLINA. 

mines  of  the  Southern  States  have  been  overrun.  Although  some  of 
these,  notably  the  Huntington  mill,  are  still  in  use  at  a  few  places,  it 
has  been  quite  clearly  demonstrated  that  such  grinding  apparatus  pro- 
duces float  gold  and  flours  the  quicksilver,  besides  which  the  mechan- 
ism is  subjected  to  great  strain  and  wear,  against  all  of  which  defects  the 
stamp  battery,  with  plate  amalgamation,  has  proven  itself  vastly  su- 
perior, and  through  all  of  its  vicissitudes  it  has  held  the  field  as  the 
most  economical  and  rational  apparatus  for  milling  and  amalgamating 
gold  ores. 

TREATMENT  OF  SULPHURET  ORES. 

As  soon  as  the  water-level  was  reached  in  the  mines,  and  the  free- 
milling  brown  ores  were  practically  exhausted,  attempts  were  made  to 
treat  the  undecomposed  sulphurets. 

MECHANICAL    METHODS. 

Probably  the  earliest  method  employed  for  the  concentration  of  these 
sulphurets  was  that  used  at  the  Yaucluse  mine  in  1847  (described  on 
page  34),  which  consisted  in  passing  the  material  over  strakes  or  in- 
clined planes.  This  was  probably  followed  by  buddies,  primitive  bump- 
ing-tables  and  more  especially  by  blankets.  Log  rockers  were  also 
used  at  an  early  date  for  this  purpose.  At  the  present  day  the  Frue, 
Embrey  and  Triumph  concentrators  are  in  general  use.  Of  these,  the 
Embrey  machine  is  considered  by  some  to  give  better  results,  especially 
where  skilled  labor  cannot  be  obtained,  and  where  the  sulphurets  are 
not  sized.  Still,  each  one  of  the  three  finds  its  strong  advocates,  and  the 
difference  in  perfection  of  concentration  obtained  by  them  is  prob- 
ably not  material.  In  some  cases — as,  for  instance,  in  the  Gold  Hill 
district — the  finely-divided  condition  of  the  gold  has  led  to  the  re-em- 
ployment of  blankets. 

At  the  Reimer  mine,  North  Carolina,  a  plant  was  in  operation  in 
1883  in  which  the  ore  was  comminuted  in  a  series  of  crushers  and  26- 
inch  rolls;  the  pulp  was  sized  into  six  grades,  from  10-  to  60-inesh,  and 
each  grade  treated  separately  by  a  Bradford  jig.  This  process  is  said 
to  have  given  good  results,  but  the  plant  was  destroyed  by  tire  soon 
after  its  erection  and  never  rebuilt.  The  same  system  of  jigging  was 
at  one  time  in  use  at  the  McGinn  mine  in  North  Carolina. 

The  earliest  treatment  of  the  concentrated  sulphurets  was  by  regrind- 
ing  them  (in  the  raw,  unroasted  state)  in  Mexican  arrastras  and  Chilean 
mills,  with  subsequent  amalgamation,  as  described  above  in  the  prac- 
tice of  working  the  ores  at  the  Yaucluse  mine,  Virginia,  in  1847. 

In  1852-53,  a  Dr.  Holland,  of  Massachusetts,  introduced  a  roasting 
process  at  some  mines  near  Charlotte,  IsT.  C,  in  which  the  pyritic  con- 


HISTORICAL    NOTES!    MINING,    METALLURGICAL    AND    STATISTICAL.        37 

centrales  were  mixed  with  nitrate  of  potash  or  soda  and  roasted  in  a 
reverberatory  furnace  at  a  low  heat. 

Lieber  stated  1  in  1856  that  a  process  for  roasting  sulphurets,  with  sub- 
sequent amalgamation,  had  been  introduced  by  a  Mr.  C.  Bingel  at  a 
mine  near  Rutherfordton,  ~N.  C.  (this  was  probably  the  Alta  mine), 
and  was  afterwards  practiced  with  success  on  old  tailings  at  the  Gold 
Hill  and  other  mines  in  North  Carolina. 

In  the  past  history  of  the  Southern  mines  a  vast  number  of  roasting 
processes  and  furnaces  have  been  introduced,  many  of  them  approach- 
ing the  ludicrous,  but  they  have  never  lasted  beyond  the  experimental 
stage.     Heap-roasting  with  salt  was  also  tried. 

Some  of  the  furnaces,  particularly  of  the  well-known  reverberatory 
type,  were  successful  enough  so  far  as  the  roasting  went;  the  fault  lay  in 
the  prevalent  and  popular  belief  that,  by  oxidizing  the  sulphurets,  the 
difficulty  of  amalgamating  the  precious  metals,  which  had  been  set 
free,  would  be  removed,  when  in  fact  the  resulting  coating  of  iron  oxide 
was  nearly  as  fatal  to  the  work  as  the  sulphide  had  been. 

The  Bartlett  method  of  making  white  lead-zinc  oxide  was  introduced 
at  the  Silver  Hill  mine,  North  Carolina,  in  1871-2.  It  consisted  in 
roasting  the  concentrated  galena-blende  and  condensing  the  zinc-lead 
oxide  fumes,  which  made  a  good  paint  material.  The  process  is  said 
to  have  been  carried  on  successfully  until  all  the  available  suitable  ma- 
terial was  exhausted. 

CHEMICAL    TREATMENT. 

The  next  step  was  in  the  direction  of  a  chemical  treatment  of  these 
refractory  sulphurets.  It  would  be  useless  to  outline  the  numerous 
processes  that  were  experimented  with  for  this  purpose.  The  South 
has  been,  much  to  its  detriment,  the  "  proving  ground  "  of  almost  all 
the  patent  gold-saving  processes  invented,  and  the  greater  proportion  of 
these  have,  as  might  have  been  predicted,  resulted  in  utter  failure. 
Of  all  these  the  chlorination  process  is  practically  the  only  survivor; 
and  there  is  a  possibility  of  the  successful  application  of  the  cyanide 
process. 

THE  CHLORINATION    PROCESS. 

It  was  not  until  1879  that  the  successful  treatment  of  pyritic  sul- 
phurets was  accomplished  by  the  introduction  of  the  chlorination  pro- 
cess. In  that  year  a  Hears  chlorination  plant  was  erected  at  the 
Phoenix  mine,  North  Carolina,  under  the  management  of  Mr.  A.  Thies, 
who  soon  improved  on  and  developed  it  into  what  is  now  universally 
known  as  the  Thies  process. 

1  Report  on  the  Survey  of  South  Carolina  for  1856,  p.  47. 


38  GOLD    MINING    IN    NOKTH    CAROLINA. 

Iii  1880  a  chlorination  plant  (the  Davis  and  Tyson  Metallurgical 
Works)  was  erected  two  miles  south  of  Salisbury,  X.  C.  The  process 
used  was  known  as  the  Davis  process,  which  differed  from  the  Clears 
only  in  the  method  of  precipitating  the  gold  with  charcoal  instead  of 
ferrous  sulphate.  These  works  were  in  spasmodic  operation  on  cus- 
tom ores  for  several  years. 

In  1881  a  Davis  plant  was  erected  at  the  Reimer  mine,  Xorth  Caro- 
lina, but  was  shortly  burned  down,  before  thorough  testing. 

In  1882  the  Plattner  chlorination  process  was  introduced  at  the 
Tucker  mine,  North  Carolina,  but  was  not  successful,  and  in  the  fol- 
lowing year  the  Mears  process  was  substituted,  which  also  had  a  short 
existence  here.  These  failures  were,  however,  most  probably  due  to 
the  impracticable  application  of  the  methods  rather  than  to  the  char- 
acter of  the  methods  themselves. 

Experiments  were  made  several  years  ago  by  Mr.  P.  G.  Lidner  at  the 
Brewer  mine  in  South  Carolina,  and  at  Dahlonega,  Ga.,  with  a  chlor- 
ination process  for  treating  the  ore  in  bulk;  and  a  plant  for  a  patent 
electrolytic-chlorination  process  was  erected  in  1895  at  the  Clopton 
mine,  Villa  Rica,  Ga.  None  of  these  have,  however,  met  with  prac- 
tical success. 

At  the  present  time  the  Thies  process  is  in  successful  use  at  the 
Haile  mine,  South  Carolina,  and  the  Franklin  and  Royal  mines,  Georgia. 

THE  CYANIDE   PROCESS. 

The  cyanide  process  has  so  far  found  but  little  application  in  the 
South.  In  May,  1892,  Mr.  Richard  Eames,  of  Salisbury,  X.  C,  ex- 
perimented with  cyanide  at  the  Gold  Hill  mine,  1ST.  C,  extracting  60 
per  cent  of  the  assay  value.  In  the  summer  of  1893,  a  10-ton  cyanide 
plant  was  working  at  the  Moratock  mine,  1ST.  G,  but  the  operations 
were  soon  relinquished  here  on  account  of  the  low  grade  and  character 
of  the  ore.  Later  in  the  same  year,  a  cyanide  plant  was  in  operation  at 
the  Gilmer  mines  in  Goochland  county,  Ya. ;  with  what  success  could 
not  be  ascertained.  At  the  Franklin  mine,  Ga.,  a  treatment  of  the 
ores  with  cyanide  was  attempted  before  the  introduction  of  the  chlor- 
ination process.  It  proved  successful  on  the  oxidized  tailings  from  the 
old  dumps;  but  the  extraction  from  fresh  sulphurets  was  insufficient  to 
warrant  its  continuation. 

In  1895  cyanide  experiments  were  made  at  the  Sawyer  mine,  in  Ran- 
dolph county,  1ST.  C,  but  were  soon  abandoned.  In  1896  a  30-ton 
cyanide  plant  was  erected  at  the  Russell  mine,  N.  C,  by  the  American 
Cyanide  Gold  and  Silver  Recovery  Company  of  Denver,  Col.,  and  a 
small  plant  was  also  built  at  the  Cabin  Creek  (Burns)  mine,  X.  C,  by 
the  same  company,  but  neither  of  these  lias  yet  been  put  in  practical 
operation. 


!l 


HISTORICAL    NOTES:    MINING,    METALLURGICAL    AND    STATISTICAL.        39 

OTHER   CHEMICAL   PROCESSES. 

The  Hunt  and  Douglas  process  was  successfully  applied  in  IS 80  to 
the  ores  of  the  Conrad  Hill  mine,  N.  C.  The  roasted  snlphurets  were 
leached  with  a  ferrous  chloride  solution,  converting  the  copper  to  a 
soluble  chloride,  from  which  it  was  precipitated  as  metallic  cement  on 
scrap  iron. 

The  Designolle  process,  which  consisted  in  treating  the  roasted  ore 
with  corrosive  sublimate  in  iron  vessels,  was  only  moderately  successful 
in  its  application,  for  the  reason  that  it  made  a  very  base  bullion,  the 
iron  of  the  apparatus  invariably  precipitating  any  soluble  salts  formed 
in  the  roasting.  It  was  worked  for  a  time,  during  3  882-83,  at  a  custom 
plant  near  Charlotte,  N.  C. ;  at  the  New  Discovery  mine,  Rowan  county, 
N.  C.  (1883),  and  at  the  Haile  mine,1  S.  C.  (1883). 

A  plant  for  the  extraction  of  gold  from  pyritic  concentrates,  with  the 
recovery  of  the  sulphuric  acid,  was  erected  early  in  the  present  decade 
at  Blacksburg,  S.  C,  mainly  for  the  treatment  of  custom  ores.  The 
concentrates  were  roasted  in  a  Walker-Carter  muffle  furnace,  which 
was  connected  with  lead  chambers.  The  amalgamation  of  the  roasted 
product  Avas  carried  on  by  a  patent  process  known  as  the  Caloric  Reduc- 
tion Company's  process,  the  principle  of  which  was  a.  volatilization  of 
mercury  into  the  mass  of  the  pulp,  followed  by  a  condensation  of  the 
same,  the  amalgam  being  led  into  settling  vats.  It  was  proposed  to  use 
the  tailing  residues  for  the  manufacture  of  red  paint.  The  scheme,  as 
might  have  been  predicted,  was  a  failure.  A  similar  process,  known 
as  the  Phelps  process,  had  already  been  unsuccessfully  tried  on  North 
Carolina  ores,  in  (about)  1877,  in  an  experimental  plant  situated  at 
Philadelphia. 

Attempts  at  pyritic  smelting  were  made  as  early  as  1847  at  the  Vau- 
cluse  mine  in  Virginia  by  Commodore  Stockton,  but  resulted  in  failure. 

Matte  smelting,  followed  by  refining  in  reverberatory  furnaces, 
was  practiced  (about  1881-1882)  on  the  copper  ores  of  the  Conrad  Hill 
and  the  North  State  mines  in  North  Carolina. 

Experiments  on  matting  auriferous  sulphurets  from  the  Haile  mine, 
S.  C,  were  made  in  1886  by  Mr.  E.  G.  Spilsbury,"  but  proved  unsuc- 
cessful. 

Regarding  smelting  processes  in  the  South,  probably  most  has  been 
done  in  the  attempted  treatment  of  the  complex  galena-blende  ares, 
carrying  silver  and  gold,  of  the  Silver  Hill  and  Silver  Valley  mines, 
Davidson  county,  N.  C. 

The  process  in  use  at  Silver  Hill,  as  early  as  1S53,  was  heap-roasting, 
followed  by  wet-crushing  in  a  stamp  battery,  the  zinc  oxide  being  dis- 

1  Trans.  Amer.  Inst.  Min.  Enps.,  vol.  xv,  p.  771. 

2  Trans.  Amer.  [nst.  Min.  Eiig*.,  vol.  xv,  pp.  7(57-77"). 


40 


GOLD    MINING    IN    NORTH    CAROLINA. 


solved  and  recovered  separately,  after  which  the  residues  were  smelted 
in  the  old-fashioned  Scotch  open-hearth  lead  furnace,  and  the  precious 
metals  were  recovered  from  the  pig  lead  by  refining  in  a  cupellation 
furnace.1 

During  the  past  twelve  years  a  number  of  patent  processes  have  been 
experimentally  tried  on  the  Silver  Valley  ores  in  a  plant  situated  at 
Thomasville,  ~H.  C,  but  it  was  not  until  1895  Jhat  a  successful  process 
was  introduced  by  Mr.  Mninger,  of  Newark,  X.  J.  It  consists  of  a 
down-draught  jacket  furnace,  through  which  the  fumes  of  lead  and 
zinc  are  carried  downward  into  condensers,  where  they  are  met  by  a 
spray  of  water,  the  liquor  being  led  to  vats  where  the  lead  oxide  is 
deposited,  while  the  zinc  remains  in  solution  and  is  subsequently  pre- 
cipitated as  zinc  oxide.  The  matte,  carrying  copper,  gold  and  most 
of  the  silver,  is  tapped  from  the  well  of  the  furnace  and  cast  into  pigs. 


PRODUCTION  OF  GOLD  AND  SILVER  IN  NORTH  CAROLINA  AND 
OTHER  SOUTHERN  STATES. 

The  following  table,  compiled  from  the  production  reports  of  the 
United  States  Mint,  gives  an  estimate  of  the  gold  and  silver  production 
of  the  Southern  States  down  to  the  present  time.  The  figures  represent 
not  only  the  amounts  deposited  at  the  United  States  Mint  and  Assay 
Offices,  but  also  such  amounts  that  were  produced  and  not  turned  into 
the  mint  and  of  which  records  could  be  obtained: 

Table  I. — Estimate  of  the  Production  of  Gold  and  Silver  in  each  of  the 
Southern  States  from  1799  to  1879  and  Annually  Since. 


Year. 

Md. 

Va. 

N.  C. 

S.  C. 

Ga. 

Ala. 

Term. 

Total. 

1799-1879 

$2,500 

$3,091,700 

$19,659,600 

$2,587,900 

$14,180,500 

$365,300 

$155,300 

£40,042. N  0 

1880... 

250 

11,500 

95,000 

15,000 

120,000 

1,000 

1.500 

244.250 

1881 .... 

500 

10,000 

115.000 

40,000 

125,000 

1,000 

1,750 

293,250 

1883.... 

1,000 

15,000 

215,000 

25,000 

250,000 

3,500 

250 

509.  Toil 

1883.... 

500 

7,000 

170,000 

57,000 

200,000 

6,000 

750 

441,250 

1884.... 

500 

2,500 

160,500 

57,500 

137,000 

5,000 

300 

36o.o(iii 

1885.... 

2,000 

3,500 

155,000 

43,000 

136,000 

6,000 

300 

345.800 

1886.... 

1.000 

4,000 

178,000 

38,000 

153,500 

4,000 

500 

379.1  1  0 

1887... 

500 

14,600 

230,000 

50.500 

110,500 

2,500 

500 

409.100 

1888  ... 

3,500 

7,500 

139,500 

39,200 

104,500 

5,600 

1.100 

300.POO 

1889.... 

3,500 

4,113 

150,174 

47,085 

108,069 

2,639 

750 

3U5.830 

1890 .... 

16,962 

6,496 

126,397 

100,294 

101,318 

2,170 

1,001 

354.t-:38 

1891... 

11,264 

6,699 

101,477 

130.149 

80,622 

2,245 

519 

332.975 

1892.... 

1,000 

5,002 

90,196 

123.881 

95,251 

2,419 

1,006 

318,755 

1893 .... 

114 

6,190 

70,505 

127,991 

100,375 

6,362 

250 

311.787 

1891  .. 

978 

7,643 

52,927 

98,763 

99,095 

4,092 

329 

263.827 

1895... 

501 

6,325 

69,196 

12S.303 

128,403 

4,708 

335 

337.771 

1896.... 

1.037 

4.466 

52.056 

100,711 

$3,810,277 

150,085 

6,695 

58J 

315.632 

Total.. 

$47,606 

$3,214,234 

$21,830,528 

$16,380,218 

431.230 

$167,022 

$45,881,115 

In  order  to  give  an  idea  of  the  fluctuation  from  1799  to  1896,  Table 
Xo.    2    is    given.     These  figures,   however,    comprise    only   the    actual 


1  Mining  Magazine,  vol.  i,  1853,  p.  367  et  scq. 


HISTORICAL    NOTES:    MINING,    METALLURGICAL    AND    STATISTICAL.        41 

United  States  Mint  and  Assay  Office  receipts,  and  do  not  include  such 
bullion  as  went  abroad,  was  sold  directly  to  local  jewellers,  or  was  coined 
by  the  Bechlters  *  at  Kutherf  ordton,  K  C. 


Table  II.- 

Statement  of 

Gold  and  Sil 

ver  prod 

ern  States 

•  /  Deposited  at  the  United  States  a 

to  1896  inclusive. 

Year. 

Amount. 

Year. 

Amount 

1793-1S23 

$47,000 

1848 

$850,692 

1S24 

5,000 

1849 

891,968 

1S25 

17,000 

1S50 

658,605 

1S26 

20,000 

1S51 

500,539 

1827 

21,000 

1S52 

711,449 

1S28 

46,000 

1S53 

486,184 

1829 

140,000 

1854 

323,489 

1S30 

466,000 

1855 

362,349 

1S31 

519,000 

1856 

325,820 

1832 

678,000 

1S57 

141,810 

1S33 

868,000 

1858 

349,323 

1834 

898,000 

1859 

379,677 

1S35 

6S6,300 

1860  . 

231,398 

1S36 

667,000 

1861 

141,778 

1S37 

282,000 

1862 

6,298 

1S3S  2 

35S,750 

1S63 

1,624 

1S39 

429,648 

1864 

6,093 

1S40 

427,311 

1865 

33,345 

1S41 

544,661 

1866 

202,000 

1S42 

723,761 

1867 

106,903 

1S43 

1,050,100 

1S6S 

155,660 

1844 

928,095 

1869 

191,738 

1S45 

986,849 

1870 

168,057 

1S46 

992,792 

1871 

138,791 

1S47 

1,018,079 

1872 

164,461 

Year. 

Amount. 

1S73 

$158,952 

1S74 

141,647 

1875 

150,012 

1876 

138,256 

1S77 

159,009 

1S78 

102,925 

1S79 

186,123 

18S0 

203,770 

18S1 

197,084 

1SS2 

229,459 

1S83 

272,475 

1884 

255.259 

1885 

239,963 

1SS6 

272,414 

1S87 

390,531 

1888 

234,947 

18S9 

224,323 

1S90 

269,997 

1S91 

254,707 

1892 

262,023 

1893 

201,904 

1894 

203,S27 

1895 

319,496 

1896 

270.210 

Total,    25.870,310 

The  following  note  concerning  this  local  coinage  by  the  Bechtlers  is 
added  by  Mr.  Geo.  B.  Hanna  of  the  LT.  S.  Assay  Office  at  Charlotte. 
K  C:   ' 

"Gold  was  coined  at  Rutherf ordton  by  three  Bechtlers:  Christian  Bechtler, 
A.  Beehtler  and  Christian  Bechtler,  Jr.  A.  Bechtler  came  in  between  C.  Becht- 
ler and   C.  Bechtler,   Jr.    I  have  in  hand  a  5-dollar  gold  piece  stamped   '  A.' 


1  Christian  Bechtler,  jeweller  by  trade,  who  resided  near  Kutherfordton,  N.  C.  was  urged 
by  residents  in  Rutherford  and  adjoining-  counties  to  coin  the  gold  of  that  neighborhood,  as 
transportation  to  the  only  mint  then  existing  (Philadelphia,  Pa.)  was  hazardous  and  difficult. 
He  commenced  coining  in  1831,  and  continued  until  his  death,  in  1S43,  when  his  nephew.  ('. 
Bechtler,  Jr.,  continued  the  minting  until  1857.  No  regular  entries  of  the  quantity  of  gold 
minted  were  made  ;  sometimes  as  much  as  $4000  to  $5000  were  coined  in  a  week  ;  and  for  a 
period  of  ten  years  the  annual  quantity  was  fairly  equal.  See  Second  Annual  Bt  port  Survey 
of  South  Carolina,  1857.  O.  M.  Lieber,  p.  135. 

2  The  years  1838  to  1847  exclude  the  amounts  deposited  at  the  New  Orleans  Mint,  which  were 
not  available  for  each  year.  The  total  amount  at  New  Orleans  in  those  years  from  the  South- 
ern States  was  only  $116,086. 


42  GOLD    MINING    IN    NORTH    CAROLINA. 

Beclitler,  and  it  is  the  most  artistic  of  all  the  5-dollar  coins.  C.  Bechtler  also 
coined  5-dollar  gold  pieces  stamped  '  Georgia  Gold  ';  a  very  few  pieces  are 
stamped  '  August  1,  1834,'  which  date  marked  a  change  in  the  U.  S.  standard 
gold  coin.  The  presumption  is  that  all  the  Bechtler  gold  coins  prior  to  this 
date  were  bought  up  at  a  premium,  and  recoined  at  a  profit  of  nearly  7  per 
cent.  The  denominations  coined  were  $1.00,  of  quite  various  patterns,  and  2% 
and  5-dollar  pieces;  the  dollar  pieces  ranged  from  27  to  30  grains.  The  coins 
were  generally  stamped  with  the  carat,  20  c.  being  the  lowest  observed.  The 
character  of  the  stamping  varied  greatly,  that  of  the  dollar  pieces  being  very 
poor,  and  these  were  extensively  counterfeited.  The  alloy  was  silver  and  the 
coin  had  a  pale  brassy  look.  Some  coins  were  specifically  stamped  '  North 
Carolina '  gold;  others  merely  '  Carolina  Gold  '  or  '  Georgia  Gold.'  " 

In  Table  ¥o.  3  the  totals  found  in  Table  No.  2,  from  the  years  1880 
to  1896,  are  distributed  among  the  various  States. 

Table  III. — Statement  of  Gold  and  Silver  Produced  in  each  of  the 
Southern  States ;  Deposited  at  the  United  States  Mint  and  Assay 
Offices  from  1880  to  1896  inclusive. 


Md. 

Va. 

N.C 

s.  c. 

Ga. 

Ala. 

Tenn. 

Total. 

1880... 

$191 

$11,071 

$77,405 

$10,071 

$103,066 

$696 

$1,270 

$203,770 

1881 . . . 

253 

9,147 

55,990 

23,093 

106,548 

700 

1,353 

197,084 

1882... 

754 

13,540 

82,473 

16,268 

114,507 

1,690 

227 

229,459 

1883... 

310 

6,343 

100,294 

48,428 

116,401 

147 

552 

272.475 

1884... 

2,024 

88,861 

48,511 

115,000 

740 

123 

255,259 

1885. . . 

.   1,539 

2,954 

64,826 

39,766 

128,148 

2,611 

119 

239,963 

1886. . . 

559 

2,873 

83,400 

36,187 

146,027 

3,051 

317 

272,414 

18S7... 

199 

12,613 

216,788 

52,142 

107,531 

1,021 

231 

390,531 

1888... 

.   2,174 

6,514 

88,641 

37,40S 

97,824 

1,47S 

908 

234,947 

1889... 

558 

2,608 

81,196 

44,923 

92,307 

2,332 

399 

224,323 

1890... 

.   7,852 

2,601 

75,192 

97,646 

85,715 

626 

365 

269,997 

1891... 

.   4,244 

4,197 

53,993 

127,161 

63,722 

1,222 

16S 

254,707 

1892... 

249 

4,473 

50,336 

120,5S2 

83,616 

2,2S6 

4S1 

262,023 

1893... 

203 

4,300 

36,454 

122,964 

92,859 

4,S95 

229 

261,904 

1894. .. 

978 

7,643 

52,927 

98,763 

99,095 

4,092 

329 

263,827 

1895. .. 

500 

3,674 

54,649 

128,904 

128,487 

2,947 

335 

319.496 

1896. . . 

300 

3,500 

44,946 

63,688 

151,776 

5,700 

300 

270.210 

In  the  Census  Report  for  1880,  vol.  xiii,  can  be  found  statistics  con- 
cerning gold  mining  in  the  Southern  States  tabulated  under  the  follow- 
ing headings:  Directory  of  deep  mines;  Means  of  handling  water  in 
deep  mines;  Cost  of  supplies  in  deep  mines;  Directory  of  ditches;  Cost 
of  ditch  plants;  Grades  and  dimensions  of  ditches;  Length  of  water  sea- 
son; Placer  directory;  Tunnels  in  placer  mines;  Stamp  batteries;  Amal- 
gamating mills;  Arrastras;  and  Roasting  furnaces. 


CHAPTER  III. 

"DISTRIBUTION  OF  GOLD  MINES  IN  NORTH  CAROLINA, 
WITH  MINING  NOTES.1 

The  North  Carolina  mines  are  distributed  in  three  main  belts — the 
Eastern  Carolina,  the  Carolina,  and  the  South  Mountain  belts  (see 
pp.  14,  15-18). 

The  distribution  of  gold  deposits  and  geological  formations  in  North 
Carolina  is  indicated  in  a  general  way  by  the  accompanying  map 
(fig.  3,  p.  44);  but  this  is  shown  in  greater  detail  and  accuracy  on  the 
larger  map  which  accompanies  Bulletin  3  of  the  Survey  reports. 

The  mining  districts  of  North  Carolina  have  been  more  extensively 
developed  than  those  in  any  other  portion  of  the  South;  although 
to-day  a  comparatively  small  number  of  the  mines  are  in  operation. 
Of  these,  very  few  can  be  said  to  be  steady  producers,  most  of  the  work 
being  prospecting  and  preliminary  development,  with  irregular  and 
spasmodic  output.  Petty  mining,  chiefly  in  the  placer  ground,  is  car- 
ried on  by  tributors  in  various  parts  of  the  State. 

THE  EASTERN  CAROLINA  BELT. 

The  principal  mines  are  situated  in  Warren,  Halifax,  Franklin  and 
Nash  counties,  in  an  area  covering  about  300  square  miles,  and  ex- 
tending in  a  southwesterly  direction  from  a  point  near  the  Thomas  mine, 
1^  miles  northeast  of  Ransoms  bridge,  to  and  across  Tar  river. 

Among  the  mines  in  this  belt  are  the  Thomas,  Kearney,  Taylor, 
Mann,  Davis,  NickArrington,  MannArrington,  and  Portis.  Of  these 
the  two  latter  are,  perhaps,  of  most  importance. 

The  Mann-Arkington  mine  is  situated  in  the  northwest  corner  of 
Nash  county,  at  Argo  P.  O.  The  country-rock  is  chlorite-schist,  in  part 
porphyrinic,  striking  N.  60°  E.  and  dipping  40°  S.E.  The  ore-body 
consists  of  quartz  lenses  from  minute  size  up  to  12  inches  in  thickness, 

1  For  fuller  description  of  some  of  the  mines,  the  reader  is  referred  to : 

Geological  Report  of  the  Midland  Counties  of  North  Carolina,  by  Ebenezer  Emmons,  New 
York,  1856. 

"The  Ores  of  North  Carolina,"  by  W.  C.  Kerr  and  George  B.  Hanna,  Nortli  Carolina 
Geological  Survey,  1887. 

"The  Gold  Deposits  of  North  Carolina,1'  by  H.  B.  C.  Nitze  and  G.  B.  Hanna.  North  Carolina 
Geological  Survey,  1896.    Bull.  No.  3. 

Unless  otherwise  stated,  the  mines  are  not  at  present  working.  The  values  of  the  ores  arc 
not  given  on  our  authority  ;  the  same  is  true  of  the  dimensions  of  the  ore  bodies  in  abandoned 
mines  and  in  such  as  could  not  be  examined. 


*—h 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  40 

imperfectly  interlaminated  in  the  schists  and  often  cutting  the  same  at 
low  angles.  The  quartz  is  usually  saccharoidal.  The  mine  has  been 
opened  to  a  depth  of  about  108  feet  and,  so  far  as  is  known,  was  last 
worked  early  in  1894. 

The  Portis  mine  is  situated  near  Ransoms  bridge  in  the  northeastern 
corner  of  Franklin  county.  The  country-rock  is  diorite.  The  ore- 
bodies  lie  in  two  intersecting  belts  of  reticulated  quartz-veins,  each 
about  9  feet  in  total  width.  No  work  further  than  prospecting  has 
been  done  on  these.  Small  irregular  quartz-stringers  occur  promis- 
cuously throughout  the  country-rock,  and  the  saprolites  in  general  are 
stated  to  be  auriferous.  The  only  work  of  any  consequence  done  here 
was  surface  sluicing  and  hydraulicking  to  a  depth  of  15  to  30  feet. 
Sufficient  water  supply  and  head  are  difficult  to  obtain.  It  is  stated 
that  1000  cubic  yards,  washed  in  one  of  the  sluice  lines,  yielded  1018 
pennyweights  of  gold,  the  loose  vein-rock  obtained  in  this  mass  assaying 
about  $8  per  ton. 

THE   CAROLINA  BELT. 

Granville,  Person,  Alamance,  Orange,  and  Chatham  counties  are  in- 
cluded in  this  belt,  being  at  its  northern  extremity;  but  little  work  of 
consequence  has  been  done  here.  A  newly  discovered  belt  of  veins  has 
been  recently  opened  three  or  four  miles  east  of  Oxford  (Chatham 
mine) ;  another  in  the  northern  part  of  Granville  county,  near  Adoniram 
and  Venable;  and  still  another  near  the  northwest  border  of  the  county, 
in  the  copper  belt  (Hollo way  mine). 

MINES    IN    GUILFORD    COUNTY. 

Among  the  principal  mines  are  the  Fisher  Hill,  Millis  Hill,  Hodges 
Hill  (Hodgins),  Fentress  (North  Carolina),  Twin,  Gardner  Hill,  Jacks 
Hill,  North  State  (McCullough),  Lindsay,  Deep  River,  Beason,  Har- 
land  and  Beard,  situated  from  3  to  10  miles  south  and  southwest  from 
Greensboro  in  a  general  direction  towards  Jamestown.  The  country- 
rock  is  granitic. 

The  Fisher  Hill  and  Millis  Hill  mines  are  five  to  six  miles  south 
of  Greensboro.  There  are  two  systems  of  parallel  veins,  the  first  run- 
ning north  and  south  and  the  second  northeast  and  southwest.  The 
aggregate  length  of  the  veins  on  this  property  is  stated  to  be  S  or  10 
miles.  The  vein  which  has  been  most  extensively  worked  varies  from 
10  inches  to  4  feet  in  thickness  and  has  been  successfully  operated  at 
several  points.  The  mill  consists  of  ten  stamps  and  was  running  in 
1886  and  1887. 

The  Hodges  Hill  (Hodgins)  mine  is  two  miles  east  of  the  Fisher 
Hill.  The  ore  is  quartz  and  chalcopyrite,  in  a  flat  vein  from  G  inches 
to  12  feet  thick. 


46  GOLD    MINING    IN    NORTH    CAROLINA. 

The  North  Carolina  (Fentress)  mine  is  9  to  10  miles  south  of 
Greensboro.  The  general  strike  of  the  vein  is  X.  25°  E.;  its  dip  ranges 
from  38°  to  60°.  The  quartz  outcrop  has  been  traced  for  three  miles. 
The  ore  is  chalcopyrite  in  quartz  and  siderite,  containing  gold.  It  was 
formerly  worked  for  copper.  The  mine  has  been  opened  to  a  depth  of 
310  feet,  where  the  ore-shoot  was  80  to  90  feet  long  and  34  inches 
wide.  The  thickness  of  the  vein  varies  from  this  to  as  high  as  13  feet. 
It  was  last  worked  in  1856,  and  the  ores  which  were  shipped  ranged 
from  14  to  23  per  cent,  copper. 

The  Twin  mine  is  six  miles  southwest  of  Greensboro.  There  are 
two  parallel  veins  separated  by  4  feet  of  slate.  The  strike  is  X.  40'  E. 
and  the  dip  S.E.  The  thickness  of  the  vein  is  about  18  inches,  the 
ore  being  auriferous  quartz,  carrying  chalcopyrite. 

The  Gardner  Hill  mine  is  three  miles  northeast  of  Jamestown. 
There  are  supposed  to  be  three  veins  on  the  property.  The  main  vein 
strikes  N.  20°  E.  and  clips  westward.  Its  thickness  is  from  a  few 
inches  to  3  feet.  The  vein-matter  is  auriferous  quartz,  carrying  chal- 
copyrite and  some  pyrite.  The  wall-rock  is  granite,  with  a  slaty  gouge 
on  each  side  of  the  veins.  The  mine  has  been  opened  to  a  depth  of  110 
feet.  It  is  stated  x  that  the  ore  ran  from  $10  to  $20  per  ton  and  that 
the  mine  yielded  $100,000.  It  is  estimated  that  the  present  dumps 
contain  25,000  tons  of  ore.     Tentative  assays  show  $3  to  $10  per  ton. 

The  North  State  (McCullough)  mine  is  situated  about  two  miles 
west  of  south  from  Jamestown.  The  vein  strikes  northeast  and  dips 
45°  to  80°  S.E.  The  mine  was  opened  to  a  depth  of  325  feet,  where 
the  vein  was  4  to  8  feet  thick.  At  the  surface  it  was  2  feet;  at  the 
60-foot  level,  4  feet;  at  the  90-foot  level,  10  feet;  and  at  the  130-foot 
level,  24  feet  in  thickness.  The  ore  is  quartz  carrying  gold  and  sul- 
phurets  (pyrite  and  chalcopyrite).  The  brown  ores  extend  to  a  depth 
of  130  feet  and  are  said  to  have  yielded  from  $1.50  to  $5  per  bushel 
($15  to  $50  per  ton). 

The  last  work  was  done  at  the  depth  of  325  feet,  where  the  vein 
varied  from  4  to  8  feet  in  width.  The  equipment  consisted  of  20 
stamps  and  other  machinery,  which  were  last  operated  in  IS 84. 

The  Jacks  Hill  is  on  the  northern,  and  the  Lindsay  on  the  southern 
extension  of  the  North  State  vein. 

MINES    IN    RANDOLPH    COUNTY. 

The  mines  are  in  the  central  and  western  part  of  the  county.  The 
country-rock  is  argillaceous  and  chloritic  schist,  probably  in  large  part 
sheared  eruptives.    At  the  Hoover  Hill  the  rock  is  a  massive  porphyrite. 

1  Emmons,  Geol.  Rept.  Midland  counties  of  N.  C,  1856,  pp.  174,  etc. 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  47 

The  Sawyer  mine  is  5  miles  northwest  and  the  Winningham,  Slack, 
Winslow  and  Davis  Mountain  mines  are  from  2  to  5  miles  southwest 
of  Aslieboro. 

During  1895  the  application  of  the  cyanide  process  to  the  ores  of  the 
Sawyer  was  experimented  with,  but  finally  abandoned 

The  Hoover  Hill  mine  is  situated  about  10  miles  west  of  Aslieboro 
and  17  miles  east  of  south  from  High  Point.  The  country-rock 
is  a  basic  eruptive  which  is  partially  brecciated,  the  included  fragments 
being  hornstone.  In  part  the  rock  is  slightly  schistose.  The  ore-bodies 
consist  of  belts  in  this  porphyrite,  which  are  pyritic  and, filled  with 
reticulated  quartz-veins  from  less  than  1  inch  to  12  inches  in  thickness. 
The  strike  of  the  belts  is  I.E.  and  the  dip  30°-60°  S.E.  The  ore- 
bodies  are  intersected  by  pyroxenic  dikes.  The  mine  has  been  opened 
to  a  depth  exceeding  300  feet.  The  so-called  Briols  shoot  at  this  depth 
furnished  ore  worth  $8  to  $10  per  ton.  The  mine  was  working  in  June, 
1895.     It  was  equipped  with  a  20-stamp  mill  in  1882. 

The  Wilson-Kindley  mine  is  one-half  mile  southwest  from  the  Hoover 
Hill,  and  the  formation  is  similar. 

The  Jones  (Keystone)  mine  is  18  miles  east-southeast  from  Lexington. 
The  country-rock  is  a  very  schistose  phase  of  the  brecciated  porphyrite 
described  at  Hoover  Hill.  The  strike  is  N".  45°  E.  and  the  dip  80° 
LAV.  The  ore-bodies  consist  of  separate  belts,  12  to  15  feet  wide,  of 
the  schists,  impregnated  with  auriferous  pyrites  and  quartz-stringers. 
The  entire  width  of  the  ore-bearing  ground  is  stated  to  be  50  to  110 
feet.  The  ore  is  cheaply  mined  in  open  cuts  by  quarrying.  A  40- 
stamp  mill  stands  on  the  property.  The  ore  is  stated  to  mill  $2.  Assay 
value  $2  to  $7  per  ton.  Pan  concentrates  run  $22  per  ton.  Cyanide 
experiments  have  been  made  in  a  small  temporary  plant,  and  it  is  stated 
that  several  tests  of  sulphureted  ores  gave  an  extraction  of  70  1o  80 
per  cent.  The  mine  is  at  present  in  operation.  The  Uharie  river,  2 
miles  distant,  is  the  nearest  supply  from  which  water  could  be  fur- 
nished by  pumping,  for  hydraulicking  and  sluicing  purposes. 

The  Herring  (or  Laughlin),  Delft  and  Parish  mines  are  in  the 
vicinity  of  the  Jones.  At  the  last-mentioned  mine  free  gold  is  found 
in  association  with  actinolite. 

The  LTharie  mine  is  near  the  Montgomery  county  line  on  the  Uharie 
river.  The  ore-bodies  are  similar  to  those  of  the  Russell,  which  i>  a 
short  distance  southwest  (see  p.  52);  but  unlike  that  at  the  Russell,  the 
work  here  has  been  underground,  the  depth  of  the  shaft  being  17<* 
feet.     A  10-stamp  mill  was  erected  in  1887. 

MINES    IN    DAVIDSON    COUNTY. 

The  Lalor  (or  Allen),  Loftin,  Eureka  and  Black  mines  arc  situated 
from  2  to  3  miles  southeast  of  Thomasville  in  the  granite.      The  ores 


48  GOLD    MINING    IN    NORTH    CAROLINA. 

contain  gold,  silver  and  copper.  At  the  Lalor  mine  the  depth  of  the 
workings  is  140  feet.  It  was  last  operated  in  1882  by  the  Campbell 
Mining  and  Reduction  Company  of  Kew  York.  The  mill  contains  10 
stamps  and  concentrating  machinery.  The  concentrates  contained  suf- 
ficient copper  sulphurets  to  make  a  smelting  ore. 

Two  of  the  more  important  mines  in  this  county  are  the  Silver  Hill 
and  the  Silver  Valley. 

The  Silver  Hill  (Washington)  mine  is  10  miles  southeast  from 
Lexington.  The  country  is  chloritic  schist  striking  X.  35 ~  E.  and  dip- 
ping 57°  !N7W.;  it  is  accompanied  by  an  eruptive  porphyrite  similar  to 
that  of  Hoover  Hill.  The  ore  is  schist  and  quartz,  carrying  a  complex 
mixture  of  pyrite,  galena,  zinc-blende  and  chalcopyrite.  The  galena  is 
rich  in  silver.     A  general  average  of  200  tests  of  Silver  Hill  ore  shows:1 

Per  Cent. 

Galena 21.9 

Pyrite    17.1 

Chalcopyrite    '. 1.8 

Zinc-blende 59.2 

Silver  and  gold 0.025 


100.025 


The  difficulty  of  successfully  treating  this  complex  combination  of 
sulphurets  has  repeatedly  been  felt  here.  A  mechanical  separation  of 
the  galena  and  blende  by  buddies  and  similar  machinery  was  perhaps 
the  most  successful  of  the  vast  number  of  concentrating  processes  tried, 
but  even  here  the  assays  of  the  tailings  and  slimes  showed  great  loss. 
The  ore  was  for  a  time  treated  with  some  success,  without  any  separa- 
tion, for  the  combined  oxides  of  lead  and  zinc  used  in  paint  manufac- 
ture. This  class  of  ore  is  best  adapted  to  a  smelting  process  in  com- 
bination with  copper  ores,  such  as  has  been  successfully  done  on  the 
similar  ores  of  the  Silver  Valley  mine.      (See  p.  49.) 

As  far  as  the  200-foot  level  certain  portions  of  the  vein  were  filled 
with  argentiferous  galena,  which  presented  no  difficulty  in  treatment. 
But  below  that  level  the  blende  gradually  increases  and  finally  pre- 
dominates over  the  galena. 

Various  assays  of  the  Silver  Hill  ores  show: 

Carbonate  Ores.  Pyritie  Ores. 
(1)                    '2^  (3)  (-P 

Gold,  per  ton SS.27  $2.07  S3. 10         S10.34 

Silver,      " 20.36  4.65  4.01  2.97 

S28.63  S6.72  S7.ll         S13.31 

Lead,  per  cent 3.S0  31.94  0.67  

Zinc,  "  . 27.28  2.0S  

1  Ores  of  North  Carolina,  by  W.  C.  Kerr  and  G.  B.  Hanna,  18ST,  p.  197. 


—  •    -^ 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  49 

Galena  and  Blende  Ores. 

(5)  (6)  (7)  (8)  (9) 

Gold,  per  ton $4.13        $6.20        $4.13         $ $ 

Silver       "       3.23         10.73         11.25  23.86        103.44 

.     $7.36       $16.93       $15.3S         $25.86       $103.44 

Lead,  per  cent 22.94        56.72         12.57  49.00  52.00 

Zinc,        "  7.14  31.29  

The  mine  has  been  worked  to  a  depth  of  GOO  feet  by  numerous  and 
extensive  levels.  There  are  two  parallel  veins  or  lodes,  known  as  the 
East  and  West,  about  2S  feet  apart.  The  strike  is  E".E.  and  the  dip 
45°  N.W.  At  the  60-foot  level  they  come  together,  making  20  feet 
in  width;  at  the  160-foot  level  the  distance  between  the  veins  again 
widens  to  32  feet,  and  the  clip  approaches  the  vertical.  At  the  200-foot 
level  the  width  of  the  west  lode  is  10  to  15  feet.  This  mine  was  dis- 
covered in  1838;  it  was  last  worked  12  years  ago. 

The  Silver  Valley  mine  is  situated  5  miles  northeast  of  the  Silver 
Hill.  The  character  of  the  country  and  the  ore  are  similar  to  those 
at  Silver  Hill.  The  strike  of  the  lode  is  E~.E.  with  a  dip  of  45°  N.W. 
The  hanging  is  siliceous  argillaceous  schist,  and  the  foot-wall,  a  hard 
hornstone  (devitrifled  quartz-porphyry).  The  outcrop  is  a  barren 
milky  quartz,  20  feet  wide;  the  sulphurets  appear  at  a  depth  of  60 
feet.  The  mine  has  been  opened  to  a  depth  of  120  feet.  The  lode  is 
from  5  to  12  feet  in  width  and  consists  of  alternate  bands  of  slate, 
quartz  and  sulphurets,  the  latter  seams  being  from  3  to  18  inches  thick. 
A  20-stamp  mill  stands  on  the  property. 

Some  assays  of  the  Silver  Valley  ores  show: 

Galena  and  Blende  Ores. 

(1)  (2)  (3) 

Gold,  per  ton $ $4.13        $ 

Silver,       "       17.19         176.49  3S.14 

$17.19       $1S0.62         $38.14 

Lead,  per  cent 15.54  55.25  38.80 

Zinc,  "  31.43  11.24  32.00 

Concentrates. 

(4)  (5)  (6)  (7) 

Gold,  per  ton $4.13  $4.13  $1.03  $1.65 

Silver,       "       23.01  44.74  13.0S  14.34 

$27.14         $4S.S7         $14.11         $15.99 

Lead,  per  cent 11.18  47.62  9.63  8.13 

Zinc,         "         27.70  12.6S  27.S4  33.54 

The  mine  was  last  operated  in  the  latter  part  of  1893,  and  the  ores 
were  smelted  in  a  furnace  at  Thomasville  (Xorth  Carolina   Smelting 
Co.).     Many  attempts  have  been  made  at  various  times  to  treat  these 
4 


50  GOLD    MINING    IN    NORTH    CAROLINA. 

complex  ores,  but  unsuccessfully  until  this  last  time.  A  description  of 
this  smelting  process,  by  Dr.  Gr.  "W.  Lehmann,  of  Baltimore,  MxL,  is 
therefore  deemed  of  interest  and  is  given  here  in  his  words: 

"  The  smelting  plant  situated  at  Thomasville,  X.  C,  on  the  line  of  the 
Southern  Railroad  and  within  13  miles  of  the  mines  of  the  Silver  Valley  Mining 
Company,  was  erected  especially  for  the  treatment  of  the  refractory  ores  from, 
this  mine. 

"  The  composition  of  the  ore  is  zinc-blende,  galena,  iron  sulphides,  together 
with  some  little  copper,  silver  and  gold.  An  average  analysis  representing  a 
large  lot  delivered  at  the  smelter  gave:  Zn.,  28  per  cent.;  Pb.,  12  per  cent.;  Cu., 
0.5  per  cent.;  Ag.,  21  ounces  per  ton;  Au.,  0.06  ounces  per  ton.  Quite  a  number 
of  patent  processes  have  been  in  operation  since  the  last  10  years  at  the  works 
in  order  to  profitably  reduce  the  several  metals,  but  none  of  these  processes 
have  gone  beyond  the  experimental  stage,  since  none  of  them  proved  a  commer- 
cial success,  until  about  two  years  ago.  At  that  time  Mr.  Robert  Xininger.  of 
Newark,  X.  J.,  erected  a  plant  which  deals  with  the  subject  of  treating  refrac- 
tory ores  successfully.     The  plant  consists  essentially  of: 

"  1.  Down-draft  jacket  furnace  connected  with  two  horizontal  jackets,  one  on 
each  side  of  the  furnace; 

"2.  Two  condensers  connecting  with  the   horizontal  jackets; 

"  3.  Vat  house  with  a  series  of  large  vats  to  receive  the  flow  of  liquor  from  the 
condensers  and  to  collect  the  lead  and  zinc  residues; 

"  4.  A  separate  plant  for  the  treatment  of  the  lead  residues; 

"  5.  A  separate  plant  for  the  treatment  of  the  zinc  residues. 

"  The  down-draft  furnace,  as  far  as  charging  and  general  construction  is  con- 
cerned, is  operated  in  a  similar  manner  as  any  ordinary  jacket-furnace,  but  the 
arrangement  of  the  tuyeres  is  different  and  the  current  of  air  from  the  blowers 
necessary  for  the  complete  combustion  of  the  refractory  ore  is  carried  down 
through  the  charge;  thence  through  the  horizontal  jackets,  the  condensers, 
through  two  powerful  suction  blowers  along  a  series  of  dust  chambers,  and  out 
through  the  stack.  A  constant  spray  of  water  meeting  the  volatile  metallic 
fumes  of  lead  and  zinc  (together  with  what  silver  the  zinc  fumes  carry 
along)  in  the  two  condensers,  deposits  all  the  metallic  products  and  carries  them 
with  the  liquor  into  a  series  of  vats  where  the  lead  sulphite  or  sulphate  is 
deposited  on  the  bottom  of  the  vats,  carrying  the  silver  with  it.  whilst  the  zinc 
remains  in  solution  and  is  precipitated  out  of  this  solution  as  zinc  oxide. 

"  During  the  operation  the  slag  is  drawn  off  from  openings  near  the  bottom 
of  the  horizontal  jackets  near  the  furnace  proper,  whilst  the  matte  is  collected 
in  the  well  of  the  furnace  and  tapped.  This  matte  carries  the  copper,  gold,  and 
most  of  the  silver.  It  is  necessary  to  prepare  the  charges  to  the  furnace  so  as 
to  have  not  less  than  5  per  cent,  of  copper  in  your  charge;  otherwise  the  resulting 
matte  would  be  too  low  in  copper  and  would  have  to  be  treated  over  and  over 
again.  Gold  concentrates  and  even  dry  ores  can  be  used  with  advantage  as 
fluxes  and  will  help  to  make  the  process  more  profitable." 

The  cause  of  closing  down  the  furnace  was  the  difficulty  of  obtaining 
sufficient  copper  ores  for  fluxing. 

During  the  summer  of  1896  some  testing  work  was  done  on  the 
placer  deposits  forming  the  bottom  land  along  a  small  creek  that 
traverses  the  property.  The  plant  consisted  of  an  iron  washer  operated 
by  a  hydraulic  stream,  riffled  sluices,  amalgamating  tables  and  rockers. 


3 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  51 

Its  capacity  is  from  40  to  50  tons  per  day.  It  was  estimated  that  the 
minimum  yield  of  the  ground  was  $2  per  ton,  and  from  that  up  to  $4. 

Some  prospecting  was  also  done  on  a  gold-bearing  quartz-vein  situ- 
ated on  the  west  side  of  the  creek.  A  40-foot  shaft  exposed  7  feet  of 
vein  matter,  consisting  of  quartz  and  schists  carrying  pyritic  sulphurets. 
An  assay  of  an  average  sample  is  stated  to  have  given  a  value  of  $9.55 
per  ton.  Assays  of  the  more  highly  pyritic  portion  (about  4  feet  in 
width)  showed  $19.06  per  ton,  and  it  is  supposed  that  this  material  can 
be  concentrated  to  $60. 

The  Welborn  (or  Smith)  mine,  which  is  2  miles  west  of  the  Silver 
Hill,  carries  similar  ores. 

The  Conrad  Hill  mine  is  situated  6  miles  east  of  Lexington.  The 
country-rocks  are  silicified  chloritic  and  argillaceous  schists,  striking 
K  10°-20°  E.,  and  dipping  80°  KW.  There  are  two  systems  of 
veins,  one  parallel  to  the  strike  of  the  schists,  and  the  other  cutting  the 
same  at  various  angles.  The  vein-matter  is  quartz  and  siderite,  carrying 
chalcopyrite  and  gold. 

A  number  of  these  veins  have  been  opened  and  worked  by  three 
different  shafts,  the  deepest  of  which,  the  main  or  engine  shaft,  is  400 
feet  deep. 

The  thickness  of  the  ore-bodies  varies  in  different  portions  of  the 
mines  from  less  than  1  to  as  much  as  20  feet. 

The  method  of  preparing  and  treating  the  ores  at  the  time  the  mine 
was  in  operation,  was  to  partially  sort  underground,  and  then  still  fur- 
ther hand-cobb  and  pick  on  the  surface,  which  product  went  to  the 
copper  works;  the  remainder  was  crushed  and  jigged  and  the  heads 
added  to  the  hand-picked  ore  above;  the  tails  were  counted  as  waste, 
and  the  middlings  were  sent  to  the  stamp-mill  and  amalgamated,  where 
the  tailings  from  the  battery  were  again  partly  concentrated  by  buddies 
and  blankets,  and  the  concentrates  sent  to  the  copper  works. 

The  treatment  for  the  extraction  of  copper  at  first  was  to  smelt  the 
roasted  ore  in  a  shaft  furnace  for  matte,  from  which,  after  re-smelting, 
black  copper  was  obtained  and  refined.  Smelting  was  superseded  by 
the  Hunt  and  Douglas  wet  process.  The  crushed  roasted  ore  was  sub- 
jected to  a  bath  of  protochloride  of  iron,  for  the  conversion  of  the  in- 
soluble copper  minerals  to  the  soluble  chloride;  after  leaching,  the 
copper  was  precipitated  by  metallic  iron  and  then  refined.  The  resi- 
dues were  milled  and  amalgamated  in  order  to  obtain  the  gold. 

MINES  IN  MONTGOMERY  COUNTY. 

The  mines  of  this  county  are  situated  in  the  northern-central  and 
northwestern  parts,  along  the  range  of  the  Uharie  mountains. 


„^ 


52  GOLD    MINING    IN    NORTH    CAROLINA. 

The  Carter  and  Reynolds  mines  are  some  6  miles  northeast  of  Troy. 
They  have  been  worked  to  a  depth  of  100  and  80  feet,  respectively. 
Telkiride  of  gold  is  stated  to  occur  here. 

On  the  nortwest  side  of  the  Uharie  mountains  is  a  series  of  gravel 
mines  situated  in  a  line  between  the  mountains  and  the  Uharie  river. 
Among  others  may  be  mentioned  the  Bright,  Ophir  *  (Davis),  Spanish 
Oak  Gap,  Dry  Hollow,  Island  Creek,  Deep  Flat,  Pear  Tree  Hill,  Toms 
Creek,  Bunnell  Mountain,  Dutchmans  Creek,  and  the  Worth.  The 
available  portions  of  these  placers  have  been  exhausted  so  far  as  the 
present  supply  of  water  will  answer.  The  Beaver  Dam  placer  is  lo- 
cated about  5  miles  west  of  Eldorado. 

The  Sam  Christian  mine  is  situated  on  the  west  side  of  the  Uharie 
mountains  about  9  miles  southwest  of  Troy. 

The  property  contains  1350  acres.  It  was  at  one  time  extensively 
worked  as  a  gravel  mine  by  the  Sam  Christian  Company,  of  London, 
England  (the  last  operations  were  in  1893),  the  water  being  obtained 
by  pumping  from  the  Yadkin  river,  about  2-J  miles  distant.  The  plant 
consisted  of  two  Worthington  pumps  and  five  100  horse-power  boilers, 
with  a  capacity  of  delivering  to  the  mine  5,500,000  gallons  in  24  hours, 
through  a  20-inch  steel  flanged  pipe.  The  elevation  of  the  point  of 
discharge  above  the  point  of  supply  was  416  feet. 

The  two  principal  channels  were  the  Dry  Hollow  and  the  Sam 
Christian  cut.  The  thickness  of  the  gravel  varied  between  1  and  3  feet. 
The  gold  was  coarse,  mostly  in  nuggets  from  5  to  1000  dwts.  The 
country-rock  is  the  Monroe  slate,  accompanied  by  large  masses  of  vol- 
canic breccias  and  cherty  felsites  (devitrified  quartz-porphyry)  which 
contain  many  small  quartz-veins  from  -J  to  3  inches  in  thickness,  strik- 
ing ~N.  70°  W.  and  dipping  60°  ]ST.E.  Several  shafts  have  been  sunk 
on  some  of  these  narrow  veins;  but  the  attempts  at  deep  mining  were 
failures. 

Most  of  the  deep  mines  are  situated  in  the  extreme  northwestern  cor- 
ner of  the  county,  with  Eldorado  in  their  center. 

The  Etjssell  mine  (Glenbrook  Mining  Company),  is  about  3  miles 
northeast  from  Eldorado  and  but  a  short  distance  from  the  Randolph 
county  line.  The  country-rocks  are  argillaceous  slates,  both  of  soft 
and  silicifled  types.  Calcite  occurs  as  a  coating  and  in  veinlets.  In 
part  at  least,  if  not  altogether,  these  slates  are  sedimentary;  the  bedding 
and  cleavage  planes  usually  coincide,  though  not  always.  The  strike 
and  dip  is  very  variable.  Diabase  dikes  occur  in  the  country,  but  not 
in  close  proximity  to  the  mine.  The  ore-bodies  consist  of  parallel  belts 
in  the  slates,  impregnated  with  iron  sulphurets  (2  to  4  per  cent.")  and 
free   gold,   together  with  quartz-stringers.     There   are   at  least   six   of 

1  Tae  siprolites  have  been  explored  here,  and  a  belt  30  feet  wide  was  found  to  mill  §3  per  ton. 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  10,  PLATE  II. 


•    y." 


v  f 


i»r* 


iv5» 


BIG  CUT,   RUSSELL   MINE,   GLEN   BROOK,   N.   C. 


' M 


\  .1 


J 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  Do 

these  belts  within  a  distance  of  2000  feet  across  the  strike.  One  of  the 
largest  is  opened  by  the  Big  Cut,  an  open  pit  about  300  feet  long  by  150 
feet  wide  by  60  feet  deep  (Plate  II).  On  the  eastern  edge  of  this  cut  is 
a  shaft  150  feet  deep,  from  the  bottom  of  which  the  ore  has  been 
&toped  upward.  It  is  stated  that  the  entire  material  from  the  cut  aver- 
aged about  $2  per  ton,  mill-yield.  There  were  some  rich  streaks  from 
1-  to  5  feet  wide  which  went  much  higher.  Two  stamp-mills  are  situ- 
ated on  the  property;  the  new  mill  contains  40  stamps  (Plate  III)  and 
the  old  one  (now  in  ruins)  30  stamps.  It  was  proposed  in  1895  to  treat 
the  Russell  ores  by  the  cyanide  process;  and  the  American  Cyanide 
Gold  and  Silver  Recovery  Company,  of  Denver,  Col.,  erected  a  30-ton 
plant  in  the  following  year,  and  it  is  stated  that  experimental  tests  and 
calculations  demonstrated  the  ability  to  treat  the  ore  for  $1  per  ton, 
on  a  100  ton  scale,  with  an  extraction  of  85  to  90  per  cent. 

The  Appalachian  (or  Coggins)  mine  is  located  near  Eldorado.  It 
is  quite  similar  in  character  to  the  Russell,  showing  large  bodies  of  low- 
grade  ore.  The  depth  of  the  last  workings  was  160  feet.  A  40-stamp 
mill  was  erected  in  1887,  and  was  moved  to  the  Jones  mine,  Randolph 
county,  in  1896. 

The  Morris  Mountain  (Davis  or  Dutton)  mine  is  one  mile  west  of 
the  Appalachian,  and  the  ore-bodies  are  similar  to  those  of  the  Russell 
and  the  Appalachian. 

The  Riggon  Hill  mine  is  located  3  miles  east  of  Eldorado.  The 
ore-body  consists  of  a  quartz-vein,  2-J  feet  in  thickness,  lying  in  and 
with  the  slate  country.  It  has  been  opened  by  a  shaft  100  feet  in 
depth.  Some  very  high-grade  ores  (both  in  gold  and  silver)  are  reported 
from  here.     Prospecting  work  was  being  done  during  the  past  summer. 

The  Steel  mine  is  situated  about  2  miles  southeast  of  Eldorado.  The 
country  is  silicifled  schist,  striking  !N".  25°  E.  and  dipping  70°  N.W. 
The  ore-bodies  (9  to  12  feet  in  thickness)  consist  of  the  schists  impreg- 
nated with  sulphurets  (galena,  blende,  chalcopyrite  and  pyrite^)  and 
intercalated  with  quartz-stringers  or  seams  from  less  than  one  up  to 
twelve  inches  in  thickness.  The  combined  thickness  of  these  ore-seams 
is  rarely  less  than  15  inches,  and  is  sometimes  more  than  3  feet.  The 
ore  contains  gold  and  silver  in  galena,  blende,  chalcopyrite  and  pyrite. 
Occasional  bunches  of  the  ore  have  been  extremely  rich,  and  assays  of 
the  entire  mass  of  the  vein-matter  have  shown  values  from  $20  to  $160 
per  ton.  The  depth  of  the  mine  is  220  feet.  It  was  last  operated  by 
the  Genesee  Gold  Mining  Company,  the  ores  being  treated  in  a  40- 
stamp  mill. 

The  Saunders  mine  is  an  extension  of  the  Steel. 

The  Moratock  mine  is  situated  8  miles  south  of  Eldorado.  The 
country-rock   is    a    massive,    devitrihed    quartz-porphyry    and   volcanic 


54:  GOLD    MINING    IN    NORTH    CAROLINA. 

breccia.  It  is  very  sparingly  impregnated  with  sulphurets  (pyrite  and 
some  chalcopyrite).  Several  small  quartz-veins  (less  than  1  inch  in 
thickness)  intersect  the  mass.  The  mine  consists  of  a  small  quarry 
opening  in  the  quartz-porphyry.  A  10-stamp  mill,  equipped  with  a 
cyanide  plant,  stands  on  the  property  and  was  last  in  operation  in  July, 
1893.  The  ore  was  reported  to  be  of  too  low  grade  to  be  profitably 
treated. 

MINES  IN  STANLY  COUNTY. 

The  mines  are  located  in  the  northeastern  portion  of  the  county,  more 
or  less  on  the  line  of  the  Southern  Railroad  branch  running  from  Salis- 
bury to  Norwood.  Among  the  more  important  properties  are  the  Haith- 
cock,  Hearne,  Crawford,  Lowder,  Parker,  Crowell  and  Barringer. 

The  Haithcock  and  Hearne  mines  are  about  two  miles  northwest  of 
Albemarle.  The  country-rock  is  clay-slate,  striking  N.E.,  and  associated 
with  eruptives.  The  quartz-veins  are  stated  to  be  from  2  to  6  feet  in 
thickness. 

The  Crawford  mine,  situated  4  miles  northeast  from  Albemarle,  is 
a  newly  discovered  placer,  and  is  described  in  detail  on  p.  91. 

The  Lowder  mine  is  situated  4  miles  west  of  Albemarle.  It  was 
opened  in  1835,  but  has  not  been  operated  since  the  war.  Previous  to 
that  time  it  was  worked  along  the  outcrop  and  to  a  depth  of  65  feet. 
The  quartz-vein  is  stated  to  be  3-|  feet  in  thickness,  lying  approx- 
imately with  the  slates  in  strike  and  dip.  During  the  summer  of  1895 
the  mine  was  unwatered,  and  some  prospecting  work  was  carried  on. 

The  Parker  mine  (the  New  London  Estates  Company,  L'td.)  is  situ- 
ated at  New  London,  9  miles  northwest  of  Albemarle.  The  property 
comprises  about  1200  acres.  It  is  now  in  litigation.  The  country 
slates  resemble  those  of  the  Monroe  type  (see  p.  16);  they  are  intruded 
by  successive  flows  of  greenstone  porphyry  and  more  basic  eruptives, 
in  part  brecciated.  The  mine  shafts  have  disclosed  at  least  two  volcanic 
sheets,  from  2  to  3  feet  thick  each,  lying  horizontally  and  separated  by 
sedimentary  slates.  In  places  the  greenstone  is  squeezed  into  nearly 
vertical  schistose  masses.  The  country  is  intersected  by  numberless 
quartz-stringers  and  several  larger  quartz-veins,  which  are  auriferous. 
The  principal  work  at  the  Parker  consisted  of  hydraulicking  (see  Plate 
IV)  in  several  old  gravel  channels,  which  are  stated  to  have  yielded 
over  $200,000.  The  gold  was  coarse,  usually  in  nuggets  from  a  few 
pennyweights  up  to  3  pounds.  The  fineness  of  the  gold  is  950  to  970. 
The  value  of  the  gravel  is  stated  to  vary  from  44  cents  to  $2.40  per 
cubic  yard. 

In  one  of  the  hydraulic  cuts  the  bed-rock  underlying  the  grit  was 
decomposed  greenstone.     Test-pits  have  shown  that  this  bed-rock  is  but 


Jl 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  10,  PLATE  V. 

""-■--  -"  <q 


STAND-PIPE,    PARKER   MINE. 


SLUICES,    PARKER    MINE,   STANLY  COUNTY,   N.   C. 


• 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  55 

a  sheet  of  greenstone  about  3  feet  thick,  and  that  it  is  underlain  by 
another  auriferous  gravel  deposit,  which  may  be  considered  virgin 
ground,  as  no  attempt  has  yet  been  made  to  work  it.  There  would  be 
no  great  difficulty  in  getting  a  sluice  on  the  bed-rock  beneath  this  lower 
grit,  with  sufficient  fall  to  carry  off  the  tailings. 

The  hydraulicking  plant  is  very  extensive.  It  consists  of  a  Worth- 
ington  compound  duplex  condensing  pump,  with  two  100  H.  P.  boilers 
(using  7  cords  of  wood  per  day,  at  $1  per  cord),  situated  on  the  Yadkin 
river,  4^  miles  from  the  stand-pipe  at  the  mine,  and  340  feet  below  the 
same.  The  pipe-line  on  the  lower  lift  is  20  inches  in  diameter,  flange- 
riveted,  made  of  ye-inch  steel;  on  the  upper  lift  is  a  similar  steel  pipe 
12  inches  in  diameter.  Expansion-joints  are  placed  every  quarter  of  a 
mile,  and  the  full  length  of  sleeve  (8  inches)  is  necessary  to  take  up 
the  maximum  expansion  and  contraction  of  the  pipe  caused  by  changes 
•of  temperature.  The  capacity  of  the  pump  is  1,500,000  gallons  in  12 
hours;  the  head  furnished  from  the  top  of  the  stand-pipe  to  the  mine- 
workings  is  about  90  feet.     (Plate  V.) 

Besides  the  gravel  channels  at  the  Parker,  the  saprolites  are,  in  gen- 
■eral,  auriferous;  and  a  combination  sluicing  and  milling  process 
(Dahlonega  method,  see  p.  107)  was  at  one  time  attempted  here.  The 
bank  was  undercut  with  powder  and  the  shattered  mass  moved  with  the 
giants.  The  material  ran  about  50  cents  a  ton  in  the  mill;  but  only  a 
small  percentage  of  it  was  quartz,  and  an  attempt  to  select  the  latter 
proved  unsuccessful.  The  tailings  in  the  mill  were  reasonably  low; 
but  the  loss  of  fine  gold  in  the  overflow  from  the  mill-tank,  in  connection 
with  the  exhaustion  of  the  richer  available  saprolites,  led  to  the  aban- 
donment of  the  process. 

The  mill  is  a  10-stamp  one,  built  by  the  Mecklenburg  Iron  Works  of 
'Charlotte,  E\  C.  The  weight  of  the  stamps  is  650  pounds.  In  the 
Dahlonega  practice  4  drops  were  given  80  times  per  minute,  and  round 
punched  screens  were  used;  there  were  no  inside  plates.  About  50  per 
<?ent.  of  the  gold  was  saved  in  the  mortars  between  the  dies.  The  total 
cost  of  milling  (including  1  cord  of  wood  at  $1),  with  1  hand  on  each 
shift  at  $1,  was  $4  per  24  hours. 

The  last  work  done  at  the  Parker  (fall  and  winter  of  1895)  was 
that  of  prospecting  some  of  the  larger  quartz-veins  on  the  property.  The 
Ross  shaft  was  sunk  to  a  depth  of  130  feet  and  a  vein  was  opened  by  a 
crosscut,  showing  sulphurets  of  iron  and  copper  in  white  quartz,  which 
gave  assay  values  ranging  from  $3  to  $12  per  ton.  The  same  vein  had 
been  exposed  in  a  130-foot  shaft  to  the  west  of  the  Koss,  where  assays 
of  the  quartz  showed  values  of  $3  at  the  85-foot  and  $7  at  the  130- 
foot  level. 

The  dimensions  of  the  Koss  shaft  are  5  feet  6  inches  bv  11  feet  inside 


/ 


56  GOLD    MINING    IN    NORTH    CAROLINA. 

measurements,  with  three  compartments,  the  ladder-way  being  in  the 
center.  The  timbers  (10  by  12  inches,  white  oak)  are  placed  in  square 
sets,  with  5  feet  centers.  The  cost  of  timber  is  $7  per  thousand.  The 
cost  of  the  shaft  (including  timbering)  was  estimated  at  $10  per  foot 
for  the  first  hundred  feet,  $12  for  the  next  hundred,  and  $15  for  the 
last  fifty  feet. 
Cost  of  labor: 

Mine  foreman  (who  also  does  the  framing) 12-hr.  shift,  $1.50 

Helper  to   same "         "  1.00 

Blacksmith   10-hr.    "  1.00 

Underground  men 12-hr.  shift,  75  to  85  cents. 

The  Crowell  mine  is  situated  near  the  Parker.  The  ore-body  is 
a  pyritic  belt  in  the  country  slate,  from  4  to  7  feet  in  thickness,  with  a 
narrow  pay-streak.  The  strike  is  !N".  10°  \V.,  and  the  dip  45°  X.TT. 
The  mine  has  been  worked  to  a  depth  of  125  feet. 

The  Little  Fritz  (formerly  the  Culp)  mine  is  situated  near  Glad- 
stone. Some  prospecting  work  has  lately  been  in  progress  here,  and  an 
Elspass  frictional  roller  quartz-mill  was  erected. 

The  Barringer  mine  is  situated  4  miles  southeast  of  G  old  Hill.  The 
gold  is  associated  with  limestone,  and  very  rich  ores  are  stated  to  have 
been  mined  here. 

MINES    IN    MOORE    COUNTY. 

The  mines  are  situated  in  the  northern  and  northwestern  parts  of  the 
county.  The  Jura-trias  sandstone,  the  eastern  limit  of  the  Carolina 
belt,  passes  in  a  southwesterly  direction  through  the  central  part  of  the 
county,  near  Carthage. 

The  Bell  mine  is  situated  8  miles  north-northwest  from  Carthage. 
The  country-rock  is  a  garnetiferous  chlorite-schist,  striking  N".  55°  E.^ 
and  dipping  75°  jST.A\r.  The  ore-body  consists  of  a  4-foot  belt  in  the 
schists,  containing  a  small  percentage  of  finely  disseminated  pyrite  and 
intercalations  of  siliceous  seams  from  -J  to  4  inches  in  thickness.  The 
entire  vein-matter  is  said  to  run  $12  a  ton.  It  is  stated  that  the  pay- 
streak,  4  to  S  inches  thick,  lay  against  the  foot-wall,  and  that  about 
2  feet  of  the  material  on  the  foot-wall  side  was  mined  and  milled,  yield- 
ing as  much  as  $30  a  ton.  The  mine  has  been  worked  to  a  depth  of 
110  feet  and  for  a  length  of  800  feet. 

The  Grampusville  mine  is  3  miles  southwest  of  the  Bell. 

The  Burns  mine1  is  situated  11  miles  west-northwest  from  Carthage, 
on  Cabin  creek.  The  country  is  sericitic  and  chloritic  schist,  in  part 
silicified.     The  strike  is  K  20°  E.,  and  the  dip  55°  K¥.     The  ore- 

1  See  article  by  H.  M.  Chance,  Eng.  and  Min.  Jour.  vol.  Lxi,  p.  132, 1896. 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  57 

bodies  consist  of  certain  belts  of  the  country,  impregnated  with  pyrite 
and  quartz  in  lenticular  stringers.  The  ore  is  mined  in  large  open  cuts, 
20  to  100  feet  wide  and  50  feet  deep.  The  average  ore  is  stated  to 
run  from  $2.50  to  $3  per  ton  in  free  gold.  In  1894  the  ores  were  being 
treated  in  five  Crawford  mills  by  the  Columbia  Mining  Company,  but 
the  operations  did  not  apparently  prove  successful.  In  1895  the  Cabin 
Creek  Mining  Company  built  a  10-stamp  mill,  with  bumping-tables  for 
the  concentration  of  the  sulphurets,  for  the  treatment  of  which  it  has 
been  proposed  to  introduce  the  cyanide  process. 

The  Clegg,  Cagle,  Bat  Roost,  Shields,  and  Brown  mines  are  situated 
from  ^  to  3  miles  west  and  north  of  the  Burns.  The  character  of  the 
country-rock  and  of  the  ore-bodies  at  these  is  similar  to  that  of  the  Burns. 

MINES    IN    ANSON    COUNTY. 

A  small  patch  of  crystalline  rocks,  lying  on  the  south  side  of  the 
Jura-trias  sandstone,  is  gold-bearing.  Two  mines,  the  Hamilton 
(Bailey)  and  the  Jesse  Cox,  are  situated  about  2  miles  southwest  of 
Wadesboro.     They  are  not  working  at  present. 

MINES    IN    ROWAN    COUNTY. 

The  mines  are  located  in  the  southeastern  portion  of  the  county  in 
three  general  groups: 

1.  In  a  line  extending  from  2  to  9  miles  southwest  of  Salisbury,  and 
1  to  3  miles  east  of  the  Southern  Railroad,  including  the  Hartman,. 
Yadkin,  Negus,  Harrison,  Hill,  Southern  Belle,  Goodman,  Randleman, 
and  Roseman  mines.  Not  enough  is  known  of  these  to  admit  of  an 
intelligent  description. 

2.  Two  to  seven  miles  east  and  southeast  of  Salisbury,  in  the  Dunns 
Mt.  granite  area,  including  the  Dunns  Mt.,  New  Discovery,  Bullion,  and 
Reimer  mines.  Of  these,  the  Reimer  is  fully  described  on  page  117, 
and  will  serve  as  a  type  for  the  others. 

3.  Nine  to  ten  miles  southeast  of  Salisbury  in  the  metamorphic  schists, 
including  the  Gold  Hill,  Dutch  Creek,  Gold  Knob,  Holtshauser,  Atlas,. 
and  Bame  mines. 

The  Gold  Hill  district  was  at  one  time  one  of  the  most  important 
mining  centers  in  North  Carolina,  if  not  in  the  whole  South;  although 
at  present  no  work  of  consequence  is  being  carried  on  there.  It  is  situ- 
ated about  14  miles  southeast  of  Salisbury,  in  the  southeast  corner  of 
Rowan  county,  extending  into  Cabarrus  county  on  the  south  and  Stanly 
county  on  the  east.  The  country-rocks  are  chloritic  and  argillaceous 
schists,  striking  N.  25°  to  30°  E.  and  dipping  75°  to  85°  X.AV.  A 
diabase  dike  cuts  the  schists  near  the  village  of  Gold  Hill.     The  char- 


58  GOLD    MINING    IN    NORTH    CAROLINA. 

aeter  of  the  ore-bodies  is  that  common  to  these  schists  elsewhere,  con- 
sisting of  certain  belts  in  the  schists  filled,  with  pyritic  impregnations 
and  imperfectly  conformable  lenticular  veins  and  stringers  of  quartz. 
The  principal  part  of  the  gold-bearing  zone  is  1^  miles  long  from  north- 
east to  southwest  and  §  of  a  mile  wide.  There  are  well-defined  veins  in 
the  district,  among  which  the  more  prominent  ones  are  the  Randolph, 
Barnhardt,  Honeycut,  Standard,  Trautman  and  the  McMackiiL  Some 
of  these,  such  as  the  Trautman  and  McMackin,  are  heavy  in  argentife- 
rous galena.1     (See  fig.  4,  p.  59.) 

The  first  gold  was  discovered  here  in  1842,  and  it  is  stated  that  in 
the  next  14  years  the  total  production  of  the  various  mines  was  $2,000,- 
000.  In  1853  there  was  a  population  of  about  2000  in  the  Gold  Hill 
camp,  at  which  time  the  Gold  Hill  Mining  Company  operated  5  Chilean 
mills  and  40  to  50  rockers,  working  300  hands.  Between  1845  and  1850 
the  Randolph  shaft  was  put  down  to  a  depth  of  750  feet.  This  is  the 
deepest  gold-mine  shaft  in  the  South.  The  Randolph  vein  was  worked 
in  three  principal  lenticular  ore-shoots,  pitching  to  the  northeast,  and 
varying  from  50  to  200  feet  in  length  and  from  a  few  inches  to  6  feet 
in  width.  It  is  stated  that  remarkably  rich  ores  were  obtained  in  those 
-days,  large  quantities  yielding  from  $100  to  $500  per  ton  in  the  mill. 
In  1881  the  Randolph  shaft  was  unwatered  to  the  depth  of  400  feet. 

The  method  of  working  the  Gold  Hill  ores  in  the  earlier  days  is  de- 
scribed on  p.  34. 

According  to  Emmons,2  the  amount  of  gold  produced  from  December, 
1853,  to  June,  1855  (inclusive),  as  derived  from  the  company's  books, 
was  $136,636.76,  and  the  expenses  were  $76,429,  leaving  a  net  profit 
of  $60,207.76  for  19  months.  During  the  time  which  includes  the  fore- 
going record,  however,  only  the  ore  taken  from  the  poor  pockets  was 
worked. 

It  is  estimated  by  some  that  up  to  1874  $3,000,000  worth  of  free  gold 
in  the  ore  was  produced.  In  1871,  Mr.  Amos  Howes,  the  owner  at  that 
time,  worked  3  Chilean  mills,  treating  7  tons  of  ore  per  day.  The  total 
daily  expenses  were  $95.51,  or  $13.64  per  ton.  Of  8400  tons  treated 
by  Mr.  Howes  he  produced  $200,000,  or  an  average  yield  of  $23.81 
per  ton.  It  is  estimated  that  only  33  per  cent,  of  the  gold  was  saved  by 
this  method  of  amalgamation,  67  per  cent,  going  off  in  the  tailings. 

The  first  stamp-mill  (20  stamps)  was  erected  in  IS  SI.  The  last  reg- 
ular work  was  done  in  1893  by  the  New  Gold  Hill  Company,  Mr. 
Richard  Eames,  manager,  when  the  ores  from  the  Bamhardt  vein, 
which  are  high  in  copper,  were  milled  in  a  10-stamp  mill.     (See  p.  60.) 

1  For  more  detailed  description  of  the  structure  of  the  region  see  Bull.  3;  Gold  Deposits  of 
N.  C  1896.  pp.  83-91. 
-  Geological  Report  of  the  Midland  Counties  of  North  Carolina,  1856.    E.  Emmons,  pp.  160  et  seq. 


M 


s-4-  K~^"*t,M.tt,6oldHul7eiBs; 


60  GOLD    MINING    IN    NORTH    CAROLINA. 

Mr.  Eames  carried  on  some  laboratory  experiments  in  1892  for  a  cyanide 
treatment  of  the  Gold  Hill  ores,  and  obtained  an  extraction  of  60  per 
cent,  on  100  pounds  treated.  During  the  summer  of  1895  Mr.  Bloomer, 
of  London,  experimented  with  cyanide,  but  with  what  result  is  not 
known.  Chlorination  of  the  Gold  Hill  ores  has  been  advised  but  never 
carried  out.  Xo  earnest  attempts  have  been  made  to  treat  the  sulphurets 
on  a  working  scale.     Plate  YI  shows  the  Eames  stamp-mill. 

For  the  past  number  of  years  the  only  work  at  Gold  Hill  has  been 
done  by  tributors,  who  cart  the  decomposed  material  from  the  old  mine 
dumps  to  the  Barnhardt  mill,  receiving  50  per  cent,  of  the  yield.  This 
material  mills  about  $1.50  per  ton.  The  pulp  from  the  stamps  flows 
directly  over  a  line  of  blankets  24  inches  wide,  which  are  washed  every 
20  minutes  in  a  tank;  and  the  concentrates  are  treated  in  a  series  of 
hollowed  log-rockers,  12  to  14  feet  long,  provided  with  quicksilver 
riffles  (see  Plate  I,  p.  30),  the  tailings  flowing  off  into  the  creek. 

At  the  Isenhour  mine  (Cabarrus  county),  1^  miles  southwest  from 
Gold  Hill,  the  ores  from  a  3-foot  vein  were  ground  (during  the  sum- 
mer of  1895)  in  a  Howland  pulverizer  of  6  tons  capacity  per  24 
hours.  The  pulp  was  run  over  blankets,  the  washings  from  which  were 
treated  in  rockers,  as  at  the  Barnhardt  mill,  with  a  yield  of  about  $2 
from  ores  that  assayed  from  $5  to  $7  per  ton. 

The  Gold  Knob  mine  is  some  5  miles  northwest  of  Gold  Hill  in  the 
same  general  zone  of  schists.  As  many  as  11  separate  parallel  ore-leads 
have  been  explored.  Of  these,  the  Holtshauser  vein  was  again  opened 
during  the  summer  of  1895. 

The  Dutch  Creek  mines  are  in  the  vicinity  of  Gold  Knob.  It  is 
stated  that  there  are  20  veins  on  the  property,  some  of  which  are  copper- 
bearing.  The  strike  of  the  veins  is  generally  northeast;  but  there  is 
a  second  system  striking  more  northerly  and  intersecting  the  first.  The 
more  or  less  oxidized  surface  ores  have  been  largely  worked  out  down 
to  the  water-level,  below  which  point  the  sulphurets  remain  practically 
unchanged. 

The  Atlas  and  Bame  mines  are  on  the  southwest  extension  of  the 
Dutch  Creek  veins. 

MINES  IN  CABARRUS  COUNTY. 

The  metamorphic  schists  occupy  a  narrow  strip  along  the  eastern  edge 
of  the  county,  in  which  are  located  a  series  of  mines  which  might  be 
considered  an  extension  of  the  Gold  Hill  zone.  Such  are  the  TTiden- 
house,  Nugget  (Biggers),  Eva  Furr,  Allen  Eurr,  Bocky  River,  Buffalo, 
Reed  and  Phoenix. 

The  other  mines  of  the  county  are  situated  in  the  granitic  rocks  near 
Concord  and  to  the  southeast  and  south  of  Concord.  Such  are  the 
Joel  Beed,  Montgomery,  Quaker  City,  Tucker  and  Pioneer  Mills  mines. 


J 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  61 

The  Nugget  (Biggers)  mine  is  situated  12  miles  southeast  of  Con- 
cord, near  Georgeville.  The  principal  operations  during  the  past 
three  years  have  been  hydraulicking  on  a  gravel  channel,  similar  to 
that  at  the  Crawford  mine  in  Stanly  county.  The  gold  is  coarse, 
usually  in  nuggets.  Quartz-veins  carrying  argentiferous  galena  have 
also  been  superficially  explored. 

The  Rocky  River  mine  is  10  miles  southeast  of  Concord.  The 
country  is  chloritic  schist  striking  !N".  20°  E.  and  dipping  70°  N".  \V. 
Several  lenticular  quartz-veins,  lying  more  or  less  with  the  schists, 
have  been  explored.  The  quartz  contains  pyrite,  galena,  blende  and 
chalcopyrite.  During  1895  Mr.  Wayne  Darlington,  M.  E.,  carried  on 
some  prospecting  work  on  one  of  these  in  a  shaft  130  feet  deep,  the 
total  length  of  the  drifts  being  about  200  feet.  In  the  80-foot  level 
the  quartz  was  2  J  to  3  feet  thick;  but  it  pinched  out  at  130  feet. 
Some  of  the  ore  was  heavy  in  sulphurets  and  rich  in  gold.  Crosscuts 
have  exposed  parallel  quartz-bodies.  However,  it  appears  that  no 
regular  quartz-vein  can  be  depended  on.  The  more  or  less  silicified 
schists  enclosing  the  quartz  are  impregnated  with  sulphurets  and  inter- 
calated with  small  quartz-stringers,  which,  taken  together,  will  make 
large  bodies  of  low-grade  ores.  It  is  in  such  that  the  possible  value 
of  the  mine  must  be  looked  for. 

The  Buffalo  mine,  1  mile  northeast  of  the  Rocky  river,  presents 
similar  conditions. 

The  Reed  mine  is  1-J  miles  southeast  of  the  Rocky  river.  It  is  the 
site  of  the  first  discovery  of  gold  in  North  Carolina.  In  1799,  a  17- 
pound  nugget  was  found,  and  in  1803  one  weighing  28  pounds.  The 
placer  ground  was  worked  vigorously  in  former  years  and  much  nugget- 
gold  taken  out.  The  estimated  yield  from  1804  to  1846  is  $1,000,- 
000.  During  the  year  1895  work  at  this  mine  was  revived,  but  it 
appears  to  have  been  simply  of  a  prospecting  character  and  short-lived. 
On  April  11,  1896,  a  nugget  weighing  246.83  ounces  Troy  was  found. 
It  contained  120.87  ounces  (10.072  pounds)  fine  gold,  and  5.99  ounces 
fine  silver.  During  the  latter  part  of  1896  placer  work  was  being  car- 
ried on  in  a  small  way.  The  chloritic  schists  are  accompanied  by  a 
large  body  of  greenstone,  intersected  by  numerous  quartz-veins  vary- 
ing in  thickness  from  4  inches  to  3  feet.  Some  of  these  are  gold-bear- 
ing, and  were  formerly  worked  by  a  shaft  120  feet  in  depth. 

The  Bhcenix  mine  is  situated  7  miles  southeast  of  Concord.  The 
country  schists  are  accompanied  by  a  large  mass  of  diabase,  in  which 
the  auriferous  quartz-veins  are  confined.  The  main  vein  is  the  Phoenix, 
which  was  extensively  and  successfully  worked  under  the  management 
of  Captain  A.  Thies,  now  of  the  Haile  mine,  S.  C.  Operations  ceased 
here  about   1889.     The  Phoenix  vein  strikes  X.   70°   E.   and   dips   -<>: 


62  GOLD    MINING    IN    NORTH    CAROLINA. 

!N". "W.  It  varies  from  12  inches  to  3  feet  in  thickness.  The  ore- 
shoot,  which  is  300  feet  long  and  pitches  to  the  northeast,  has  been 
worked  out  from  the  100  to  the  425-foot  level.  The  shaft  was  sunk 
to  485  feet  on  the  dip  of  the  vein,  but  not  drifted  from.  The  vein  in 
the  shaft  averages  30  inches;  but  the  rich  pay-streak,  lying  on  the 
hanging  wall,  is  only  from  2  to  3  inches  thick.  It  is  believed,  however, 
that  if  the  vein  were  drifted  on  at  the  425-foot  level  the  300-foot  ore- 
shoot  just  referred  to  would  be  reached  again.  Another  ore-shoot,  the 
Big  Sulphur,  is  situated  300  feet  southwest  of  the  above,  and  has  been 
worked  to  the  180-foot  level.  The  ore  in  the  bottom  of  this  shaft  (the 
pump  shaft,  213  feet  deep)  is  stated  to  be  14  inches  thick. 

Captain  Thies's  work  was  confined  to  the  300-foot  shoot.  The  ore 
was  quartz,  carrying  3  to  60  per  cent,  of  sulphurets  (pyrite,  chalcopyrite 
and  traces  of  galena).  Barite  and  calcite  occur  in  the  gangue.  The 
cost  of  mining  was  $4  per  ton.  Assays  show  from  1-|  per  cent,  to  3 
per  cent,  of  copper.  The  mill  yield  was  $10  per  ton,  besides  which  the 
sulphurets  contained  $7.50.  The  concentrates  ran  $30.  Chlorination 
was  first  introduced  here  in  1880.  This  was  the  Mears  process,  later 
developed  into  the  Thies  process.  A  full  description  of  this,  with  costs- 
of  working  at  the  Phoenix  mine,  has  been  given  in  a  paper  by  Dr. 
William  B.  Phillips.1 

The  mill  and  chlorination  plants  are  now  dismantled. 

The  Barrier,  Furness,  and  Gibb  mines  adjoin  the  Phoenix.  The  Fag- 
gart  is  3  miles  to  the  northeast,  and  the  Barnhardt  is  1-J  miles  east  of 
the  Faggart. 

The  Tucker  (or  California)  mine  is  1  mile  south  of  the  Phoenix.  It 
was  last  worked  in  1884,  by  a  shaft  175  feet  deep,  and  levels  117  feet 
in  total  length.  The  quartz-vein  was  15  inches  wide,  and  showed 
values  of  $15  per  ton.  In  1882  the  Plattner  chlorination  process  was- 
introduced  here;  but  this  was  later  superseded  by  the  Mears  process. 

The  Quaker  City  mine,  which  is  3  miles  north  of  the  Tucker,  has- 
not  been  worked  for  the  past  ten  years.  There  are  three  shafts  on  the 
property,  the  deepest  one  being  80  feet.  The  vein  is  stated  to  be  from 
2  to  5  feet  wide. 

The  Pioneer  Mills  group  of  mines  is  situated  13  miles  south  of  Con- 
cord. No  work  has  been  done  here  since  the  war.  The  granite  is 
accompanied  by  large  masses  of  basic  eruptive  rocks. 

MINES    IN    UNION    COUNTY. 

The  mines  are  situated  in  the  metamorphic  slates  in  the  western  part 
of  the   county.     Among  the  more  important  may  be  mentioned  the 

14kThe  Chlorination  of  Low-grade  Auriferous  Sulphides,"  Trans.  Am.  Inst.  Min.  Engs..  xviu 
pp.  313-322. 


- 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  63- 

Crowell,  Long,  Moore,  Stewart,  Smart,  Hemby,  Lewis,  Phifer,  Davis, 
Bonnie  Belle,  and  Howie  mines. 

The  Long,  Moore,  Stewart  and  Smart  are  characterized  by  the  pres- 
ence of  complex  sulphurets  (pyrite,  galena,  blende  and  sometimes  chal- 
copyrite).  At  the  Moore  mine  the  gold  is  associated  with  calcite,  which 
exists  in  a  pay-streak  4  inches  thick  on  the  hanging  wall  of  a  5-foot 
quartz-vein. 

The  Bonnie  Belle  (Washington)  mine  is  situated  8  miles  west  of 
Monroe.  The  country  is  argillaceous  schist  silicified  in  varying  de- 
grees, striking  N".  55°  E.  and  dipping  steeply  RT.W.  The  ore-deposit 
consists  of  pyrite  and  quartz  impregnations  in  the  schists.  The  width 
of  the  ore-bearing  belt  is  stated  to  be  14  feet.  It  is  intersected  by  a 
diabase  dike.  The  mine  was  in  operation  during  the  fall  of  1894. 
Ores  assaying  from  $4  to  $5  per  ton  were  treated  in  a  Chilean  mill  and 
four  drag-mills,  of  10  tons  capacity  per  24  hours;  the  pulp  was  dis- 
charged on  amalgamated  copper  plates  and  thence  to  a  Gilpin  county 
humping-table.  The  concentrates  assayed  $22,  and  the  tailings  50 
cents  per  ton. 

The  Howie  mine  is  1  mile  southwest  of  the  Bonnie  Belle.  The  ore- 
bearing  slates  are  said  to  have  a  total  width  of  400  feet,  within  which 
there  are  as  many  as  8  so-called  parallel  veins,  varying  from  18  inches 
to  16  feet  in  thickness.  Sulphurets  are  rare,  the  gold  occurring  mainly 
as  fine  films  on  the  cleavage  planes  of  the  more  or  less  silicified  slates. 
It  is  stated  that  the  ore,  when  last  mined,  yielded  $13  to  $14  in  the 
mill.  The  mine  has  been  opened  to  a  depth  of  350  feet.  Numerous 
diabase  dikes  intersect  the  ore-bodies,  which  are  said  to  be  richer  in  the 
vicinity  of  the  dikes. 

The  Monroe  slates  in  the  vicinity  of  Monroe  contain  some  narrow 
auriferous  quartz-veins,  but  they  are  scarcely  of  economical  importance,. 
at  least  so  far  as  present  explorations  have  gone. 

MINES  IN  MECKLENBURG  COUNTY. 

This  has  been  one  of  the  most  important  and  active  gold-mining 
counties  of  the  State. 

The  mines  are  distributed  over  the  entire  county,  around  Charlotte  as 
a  center.  Among  the  more  important  are  the  Davidson  Hill  (1  mile 
west  of  Charlotte),  St.  Catherine,  Kudisil,  Clark  (2^  miles  west  of  Char- 
lotte), Stephen  "Wilson  (9  miles  west  of  Charlotte),  Smith  and  Palmer, 
Howell,  Parks  (1  mile  northeast  of  Charlotte),  Taylor  and  Trotter  i  3 
miles  southwest  of  Charlotte),  Brawley  (4  miles  west  of  Charlotte), 
Arlington  (6  miles  west  of  Charlotte),  Capps,  McGinn,  Alexander  (8 
miles  northwest  of  Charlotte),  Dunn  (7  miles  northwest  of  Charlotte), 


64  GOLD    MINING    IN    NORTH    CAROLINA. 

Henderson  (7  miles  northeast  of  Charlotte),  Ferris,  Tredinick  (7  miles 
southeast  of  Charlotte),  Bay  (9  miles  southeast  of  Charlotte),  Simpson 
(10  miles  southeast  of  Charlotte),  and  Surface  Hill  (10  miles  east  of 
Charlotte). 

The  Kudisil  mine  is  1  mile  south  of  Charlotte.  In  the  upper  part 
of  the  mine  the  country  is  a  silicified,  chloritic  and  argillaceous  slate. 
At  a  depth  of  200  feet  this  gives  place  to  a  crystalline  eruptive  rock. 
The  ore-body  consists  of  two  parallel  veins  close  together  and  sepa- 
rated by  slate;  they  are  said  to  vary  in  thickness  from  2  to  6  feet. 
The  strike  is  K  30°  E.  and  the  dip  45°  IW.  The  mine  has  been 
worked  to  a  maximum  depth  of  300  feet  in  three  principal  shoots,  some 
of  which  furnished  very  rich  though  highly  sulphuretted  ores.  The 
largest  of  these  shoots  had  a  maximum  length  of  100  feet  and  a  max- 
imum thickness  of  15  feet;  it  pitched  towards  the  south,  and  was  fol- 
lowed down  to  below  the  300-foot,  but  never  found  in  the  350-foot  level. 
~No  attempt  at  concentration  and  treatment  of  sulphurets  was  made. 

The  Smith  and  Palmer  and  the  Howell  mines  are  supposed  to  be  on 
the  southwestern  extension  of  the  Rudisil.  » 

The  St.  Catherine  mine  is  on  the  northeastern  extension  of  the 
Budisil,  and  the  general  features  are  the  same.  The  deepest  workings 
are  at  the  370-foot  level.  It  is  reported  that  no  large  chimneys  of  solid 
high-grade  ore  were  found  below  the  250-foot  level;  but  between  the 
200  and  370  a  large  shoot,  4  to  60  feet  wide,  of  low-grade  ore  has  been 
worked.  The  ores  were  treated  by  battery  amalgamation,  and  the  sul- 
phurets were  concentrated;  these  were  probably  shipped  north  or  else- 
where for  smelting. 

The  Capps  mine  is  5-1  miles  northwest  of  Charlotte.  There  are  two 
convergent  veins,  the  Capps  striking  1ST.  30°  W.  and  dipping  40°  W., 
and  the  Jane  striking  "N.  40°-60°  E.,  and  dipping  steeply  eastward  (see 
Fig.  5).  The  actual  intersection  of  the  veins  has  not  been  found.  The 
Capps  was  worked  to  a  maximum  depth  of  130  feet  in  the  Bissell  shaft. 
The  filling  of  the  vein  is  quartz.  Its  thickness,  as  explored  in  the  mine 
workings,  was  not  less  than  20  feet;  definite  walls  were  only  found  at  a 
few  points.  The  pay-ore  was  not  uniformly  distributed  in  the  quartz, 
but  generally  occurred  in  layers.  Four  ore-shoots  have  been  explored. 
The  brown  ores  extend  to  a  depth  of  130  feet.  The  sulphurets  are 
pyrite,  with  some  chalcopyrite.  The  past  production  of  the  Capps  has 
been  estimated  at  over  $1,250,000. 

In  the  summer  of  1895,  Mr.  Wilkes,  the  owner  of  the  Capps.  made 
at  his  test  plant  in  Charlotte,  a  trial  run  of  50  tons  of  Capps  ore  (^sul- 
phurets)  from  the  old  dumps,  and  the  result  of  this  milling  and  chlorin- 
ation  test  was  a  yield  of  $27  per  ton. 

Between  January  and  April,  1895,  four  diamond  drill-holes  (1-inch 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA. 


65 


H^0 


No.  L 


Fig.  5.     Plan  of  Capps  Mine.     Scale,  1  iuch  =  200  feet. 


/ 


bb  GOLD    MINING    IN    NORTH    CAROLINA. 

core)  were  bored  on  the  Capps  vein.  Fig.  5  shows  their  position  relative 
to  the  mine-workings  in  plan,  as  well  as  a  vertical  section  of  the  ground 
which  they  explored. 

A,  Capps  vein;  B,  parallel  vein;  C,  Jane  vein;  D,  diorite;  E,  90-foot 
level;  F,  78-foot  level;  G,  130-foot  level;  H,  open  cut;  S,  saprolites;  m, 
drift;  n,  drift;  1,  borehole,  350  feet  deep;  2,  borehole,  250  feet  deep; 
3,  borehole,  220  feet  deep;  4,  borehole,  200  feet  deep;  5,  Penman 
shaft,  80  feet  deep;  6,  Bissell  shaft,  125  feet  deep;  7,  Mauney  shaft, 
130  feet  deep;  8,  Baldwin  shaft,  120  feet  deep;  9,  Gooch  shaft,  10, 
Old  shaft;  11,  Isabella  shaft,  160  feet  deep. 

The  Capps  vein  was  penetrated  by  each  borehole,  and  showed  a 
regular  thickness  of  about  20  feet,  with  walls  of  fine-  and  coarse- 
grained diorite,  at  times  porphyritic.  The  dip  is  quite  constant,  about 
30°  S.~W.  The  vein-matter  is  quartz,  averaging  $6  to  $7  per  ton,  as 
shown  by  assays  of  the  drill  cores.  The  drill-holes  are  certainly  very 
satisfactory,  in  so  far  as  they  prove  the  continuity  in  depth,  and  regu- 
larity in  thickness  of  the  Capps  vein;  and,  on  a  large  body  of  ore,  such 
as  this  is,  the  assays  of  the  drill  cores  are  of  value  as  showing  at  least 
the  presence  of  mineable  ores. 

The  McGinn  mine  comprises  the  Jane  vein,  worked  to  a  depth  of 
160  feet  in  the  Isabella  shaft,  and  a  cross-vein  on  the  northern  exten- 
sion of  the  Jane,  known  as  the  Copper  vein,  which  has  been  worked 
to  the  depth  of  110  feet  as  a  copper  mine. 

The  Ferris  mine  is  situated  5-J  miles  northeast  of  Charlotte.  The 
character  of  the  vein-matter  is  milky  quartz,  carrying  free  gold  and 
pyrite.  It  lies  with  the  schists,  striking  !N\  25°  E.  and  dipping  70° 
NVW.  The  quartz  is  broken  up  into  stringers,  the  widest  solid  portion 
being  12  inches.  The  vein,  as  a  whole,  is  stated  to  vary  from  2J  to  5 
feet  in  thickness.  In  the  fall  of  1894  the  mine  was  being  worked  by 
two  shafts,  respectively  56  and  95  feet  deep.  The  ore  was  treated  in 
a  Chilean  mill  of  3  tons  capacity.  It  is  stated  that  the  concentrates 
assay  from  $45  to  $60  per  ton. 

MINES    IN    GASTON    COUNTY. 

Among  the  mines  of  this  county  are  the  Oliver  and  Farrar  (12  miles 
northwest  of  Charlotte),  the  former  being  situated  on  the  Catawba  river 
near  the  "  big  bend,"  and  reported  to  have  been  worked  by  one  of  the 
early  German  settlers  prior  to  the  Revolutionary  war;  the  Rhyne 
and  Derr  (17  miles  west  of  Charlotte),  the  Duffle  and  Robinson  (16 
miles  west  of  Charlotte),  the  Smith  and  Sam  Beattie  (13  miles  west  of 
Charlotte),  the  McLean  (15  miles  southwest  of  Charlotte),  the  Long- 
Creek  and  the  Kings  Mountain. 

The  Long  Creek  mine  is  situated  in  the  northern  part  of  the  county, 


55^ 


ITOl 

■t9  *b&*a: 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  67 

about  6  miles  northwest  of  Dallas.  The  property  contains  600  acres. 
The  country-rock  is  chloritic  schist,  striking  northeast  and  dipping  85° 
northwest.  There  are  three  veins  lying  with  the  schists,  and  consist- 
ing of  lenticular  quartz-bodies.  The  Asbury  vein  was  6  to  8  feet  thick, 
and  contained  rich  ore-shoots  carrying  sulphurets  (pyrite,  chalcopyrite, 
galena,  blende  and  mispickel).  A  10-stamp  mill  was  running  here  in 
1891,  and  in  the  following  year  a  Crawford  mill  was  put  in,  which  was, 
however,  soon  abandoned,  and  the  mine  has  since  been  practically  idle. 

The  Kings  Mountain  (Catawba)  mine  is  situated  about  1|  miles 
south  of  Kings  Mountain,  a  station  on  the  Southern  Railroad,  in  the 
southwestern  corner  of  the  county.  The  country-rock  is  mica-schist, 
striking  ~H.  50°  E.  and  dipping  70°  ~N.~W.,  intercalated  with  lenticular 
masses  of  siliceous  magnesian  limestone.  These  rocks  appear  to  be  of 
sedimentary  origin.  The  ore-bodies  consist  of  large  lenticular  chimneys 
or  shoots  of  this  limestone,  containing  auriferous  quartz  and  sulphurets 
(pyrite,  chalcopyrite  and  galena  up  to  3  per  cent.).  Tellurides  also 
occur  in  very  small  quantity.  Five  such  lenses  have  been  opened  in 
the  mine. 

In  length  these  lenses  reach  about  100  feet  and  in  thickness  20  feet, 
being  separated  by  a  black  graphitic  slate  carrying  coarse  pyrite,  which 
is,  however,  barren.  The  mine  has  been  opened  to  a  depth  of  320 
feet.  At  the  time  of  our  visit  40  tons  of  ore  were  being  raised  per  24 
hours  by  a  total  force  of  20  men.  (Cost  of  mine  labor,  75  to  85  cents 
per  day).  The  rock  is  very  tough,  and  60  per  cent,  dynamite  is  used 
for  blasting.  The  mill  house  is  equipped  with  a  well-constructed  30- 
stamp  mill  built  by  the  Mecklenburg  Iron  Works,  of  Charlotte 
(Plate  VII),  and  5  Frue  vanners  (6x14  feet).  Weight  of  stamp,  750 
pounds.  Twenty  stamps  were  dropping  71  times  per  minute — the  height 
of  drop  being  5  inches.  The  ore  was  crushed  through  a  40-mesh  brass 
wire  screen.  The  mill  yield  is  stated  to  be  $3  per  ton,  with  a  loss  of 
$3  in  tailings.  Great  difficulty  was  found  in  saving  free  gold,  and 
the  quicksilver  gave  trouble  by  flouring;  this  is  ascribed  to  the  graphitic 
slates  which  occur  with  the  ore.  The  concentrates  run  $35  to  $40. 
The  total  cost  of  mining  and  milling  is  $1.75.  Two  men  are  employed 
in  the  mill  at  $1  per  day.     The  cost  of  wood  is  $1.35  per  cord. 

A  plant  for  washing  the  surface  brown  ores  and  saprolites  is  situated 
at  the  mine,  and  was  in  successful  operation  until  lately.  It  consists 
of  2  sets  of  12-foot  log-washers.  The  slimes  flowed  over  amal- 
gamated copper  plates  (12  feet  by  5  feet),  while  the  material  carried 
up  in  the  washer  was  screened  through  a  -J-inch  perforated  revolving 
screen,  and  then  through  a  20-mesh  brass  wire  revolving  screen, 
from  whence  it  passed  over  copper  amalgamating  plates.  The  coarse 
material    was   taken    to  the    stamp-mill.     A    large    proportion    of    the 


I, 


68  GOLD    MINING    IN    NORTH    CAROLINA. 

gold  remained  in  the  log-washers;  much  was  caught  on  the  plates  below 
the  fine  screens;  and  the  smallest  amount,  which  was  all  fine  gold,  was 
caught  on  the  slime  plates.  Trouble  was  also  experienced  here  by  the 
flouring  of  the  quicksilver.  The  bottom  land  lying  directly  to  the 
east  of  the  mine  is  being  worked  in  shallow  pits  by  tributors,  who  wash 
the  grit  and  soft  bed-rock  slates  in  sluice  boxes.  Panning  showed  up 
very  well  here,  and  the  ground  might  pay  for  hydraulic  working  on  a 
large  scale. 

MINES    IN   LINCOLN,    CATAWBA,    DAVIE,    ALEXANDER   AND    YADKIN    COUNTIES. 

Gold  has  been  found  in  these  counties  in  isolated  localities;  but  with 
few  exceptions  no  mining  work  of  any  consequence  has  been  done. 

The  Dixon  mine,  in  Yadkin  county,  is  a  new  discovery  (1895).  The 
vein  is  reported  to  be  several  feet  in  thickness,  of  high-grade  sugary 
quartz,  containing  some  copper.  Only  prospecting  work  has  been 
carried  on.  The  developments  consist  of  a  40-foot  shaft  and  140  feet 
of  levels  on  the  vein.  A  hundred  tons  of  ore  taken  out  had  a  reported 
value  of  $5  per  ton. 

THE    SOUTH   MOUNTAIN    BELT. 

MINES    IN    CALDWELL    COUNTY. 

The  Miller,  Scott  Hill,  Pax  Hill  and  Baker  mines  are  situated  within 
a  distance  of  1-J  miles  from  Johns  river,  and  near  the  southwestern 
boundary  line  of  the  county.  The  mines  are  located  in  each  in- 
stance in  close  proximity  to  a  wide  dike  of  olivine  diabase,  which  strikes 
through  the  country  for  many  miles  in  a  direction  X.  20°   \V. 

The  Miller,  Scott  Hill,  and  Pax  Hill  veins  strike  X.  50°-60°  E.  and 
dip  N.W. ;  as  far  as  observed  they  are  from  8  to  12  inches  in  thickness. 

At  the  Baker  mine  the  strike  of  the  veins  is  N".  85°-45°  \Y.,  and  the 
dip  is  60°-70°  N".E.  The  thickness  is  from  2  to  5  feet;  the  ores  con- 
tain auriferous  and  argentiferous  galena. 

The  Bee  Mountain  mine  is  about  4  miles  northeast  of  the  Baker 
mine,  and  the  ores  contain  zinc-blende,  galena  and  chalcopyrite. 

MINES    IN    BURKE,    MCDOWELL    AND    RUTHERFORD    COUNTIES. 

By  far  the  greater  proportion  of  gold  coming  from  these  counties 
has  been  won  by  placer  mining.  With  few  exceptions,  the  quartz- 
veins  are  too  narrow  to  justify  deep  mining.  But  even  in  the  cases 
where  the  veins  are  of  sufficient  width,  mining  operations  have  been 
very  spasmodic  and  of  limited  extent.  Placer  mining  on  a  larger  scale 
has  been  carried  on  during  the  past  years  only  at  a  few  points.      Such 


DISTRIBUTION    OF    GOLD    MINES    IN    NORTH    CAROLINA.  69 

are  the  Mills  property  and  Hancock  mines  in  Burke;  Cane  creek, 
Brackettown,  Huntsville  and  Vein  Mountain  in  McDowell,  and  Golden 
Valley  in  Rutherford  county. 

The  Mills  place  is  fully  described  elsewhere  (p.  95),  and  will  serve 
as  a  type  for  the  other  mines  of  the  district.  Petty  mining  is  almost 
constantly  in  progress  in  the  above  counties,  as  well  as  in  certain  parts 
of  Cleveland  and  Polk  counties  to  the  south. 

Of  the  quartz-mines,  those  worthy  of  mention  are  the  Idler,  Elwood 
and  Vein  Mountain. 

The  Idler  (Alta  or  Monarch)  mine  is  situated  about  5  miles  north 
of  Rutherfordton,  in  Rutherford  county.  As  many  as  13  parallel 
quartz-veins  have  been  explored  here  within  a  distance  of  \  mile.  The 
country  is  gneiss,  striking  about  x>T.  60°  W.,  and  dipping  25°  to  30° 
2\T.E.  The  veins  strike  "N.  65°  E.  The  vein-matter  is  quartz,  contain- 
ing sulphurets  (pyrite  and  some  chalcopyrite).  The  Alta  vein  has  been 
explored  to  the  depth  of  105  feet;  its  thickness  is  from  10  to  22  inches; 
the  ore  is  stated  to  yield  $10  per  ton.  The  mine  has  been  worked  in 
a  desultory  way,  but  is  now  under  water. 

The  Elwood  mine  is  1^  miles  southwest  of  the  Idler.  The  character 
of  the  country  and  of  the  veins  is  similar  to  that  of  the  Idler.  The 
ore  is  reported  to  yield  $5  in  free  gold.  The  mine  was  last  operated 
in  1893. 

The  Vein  Mountain  mine  is  situated  in  McDowell  county  on  the 
Second  Broad  river.  A  series  of  as  many  as  33  parallel  auriferous 
quartz-veins  crosses  Vein  mountain  in  a  belt  not  over  J  of  a  mile  wide. 
The  principal .  and  largest  one  of  these  is  the  Xichols,  which  has  been 
prospected  in  four  shafts  within  a  distance  of  1200  feet,  the  deepest  one 
being  117  feet.  The  strike  of  the  vein  is  K  80°  E.,  and  the  dip  75° 
N.  \\T.  Its  thickness  is  reported  to  vary  from  a  few  inches  to  3  feet. 
The  quartz  is  mineralized  with  pyrite,  galena,  blende  and  chalcopyrite. 
The  value  of  the  ores  varies  from  $2.50  to  $70  per  ton.  There  is  a 
10-stamp  mill  on  the  property,  but  it  has  never  been  operated  on  any 
regular  output. 

At  Brackettown,  5  miles  northeast  of  Vein  mountain,  an  expensive 
shaft  has  been  sunk  to  a  depth  of  126  feet,  on  a  parallel  series  of  several 
narrow  (1  to  6-inch)  quartz-veins,  with  the  fallacious  hope  that  these 
would  come  together  in  depth.  It  is  needless  to  say  that  these  small 
veins  will  not  justify  working  alone  unless  the  intervening  country 
(gneiss)  is  found  to  contain  auriferous  sulphurets  of  sufficient  richness 
to  make  large  bodies  of  low-grade  ores. 

An  isolated  belt  of  gold-bearing  rocks  has  been  mentioned  in  Hen- 
derson county,  N.  C.  (see  p.  20).  The  only  mine  situated  here  is  the 
Boylston,    12   miles   west  of  Henderson ville.     The   country-rocks   are 


/, 


/ 


70 


GOLD    MINING    IN    NORTH    CAROLINA. 


fine-grained,  mica-  and  hornblende-gneisses  and  schists,  in  part  much 
crumpled,  striking  K  20°-30°  E.,  and  dipping  35°-60°  K.W.  The 
quartz-veins  coincide,  more  or  less,  with  the  strike  of  the  schist*.  The 
mine  has  been  opened  by  a  series  of  shallow  shafts  and  short  drifts  on 
one  of  these  veins,  which  is  from  3  to  4  feet  in  thickness,  with  a  pay- 
streak  of  1  to  3  inches  on  the  hanging;  it  is  accompanied,  in  places,  by 
a  granitic  dike.  The  ores  are  reported  to  average  about  $4  per  ton 
(assay  value);  sulphurets  occur,  chiefly  pyrite  and  some  chalcopyrite. 
A  10-stamp  mill  (in  bad  repair)  stands  on  the  property.  It  has  not  been 
in  use  since  1889. 


MINES    IN    THE    MOUNTAIN    COUNTIES. 

In  the  northwestern  corner  of  North  Carolina,  the  copper  ores  of 
some  of  the  Ashe  county  mines,  and  some  small  galena-bearing  veins 
in  Watauga  and  Wilkes  counties,  are  auriferous. 

In  the  southwestern  corner  of  the  State  (in  Jackson,  Swain,  and 
Cherokee  counties)  some  placer-mining  operations  have  been  carried  on 
from  time  to  time,  notably  in  Georgetown  valley,  Jackson  county,  and 
about  the  headwaters  and  other  tributaries  of  Valley  river,  in  Cherokee 
county,  but  nowhere  successfully  on  a  very  large  scale. 

Gold  is  also  stated  to  occur  in  Macon  county,  and  this  may  be  a 
northern  extension  of  the  Georgia  belt  (see  p.  21). 

In  Horse  Cove,  Macon  county,  the  Ammons  Branch  mine  has  recently 
been  explored,  with  the  showing  of  a  10-inch  quartz-vein,  from  which 
very  rich  specimens  have  been  taken. 

In  the  southern  part  of  Clay  county  the  Warne  mine  is  situated  at 
the  northeastern  extremity  of  a  small  belt  of  auriferous  quartz-veins 
which  extends  southwesterly  into  Towne  county,  Ga.  (For  description 
see  p.  84). 


CHAPTER     IV. 

DISTRIBUTION  OF  GOLD  MINES  IN  THE  SOUTH  APPA- 
LACHIAN REGION  OTFIFR  THAN  IN  NORTH 
CAROLINA,  WITH  MINING  NOTES.1 

GOLD    MINES   IN   MARYLAND. 

The  gold  mines  are  situated  within  the  belt  of  crystalline  rocks  ex- 
tending from  Washington  to  Great  Falls,  on  the  Potomac  river,  in 
Montgomery  county,  and  also  in  the  central  and  northern  part  of  this 
county.      Geologically,  they  are  included  in  the  Virginia  belt  (see  p.  13). 

The  greatest  development  has  been  in  the  vicinity  of  Great  Falls, 
about  15  miles  west  of  Washington.  Among  the  principal  mines  in 
this  region  are  the  Maryland,  Montgomery,  Harrison  (or  Sawyer),  Irma, 
Huddleston,  and  Allerton-Ream,  situated  in  a  belt  from  7  to  8  miles 
in  width.2  The  greatest  development  was  during  the  years  1888-93,  in 
which  time  the  various  properties  were  worked.  Since  that  time  oper- 
ations have  been  carried  on  in  a  limited  way  at  the  Allerton-Ream,  Har- 
rison, Miller  and  Bethesda. 

During  the  winter  and  early  spring  of  1895  a  considerable  amount 
of  exploratory  work  was  carried  on  at  the  Bethesda  mine,  7  miles 
northwest  of  Washington,  by  the  Bethesda  Mining  Company.  -  Some 
$20,000  to  $30,000  had  formerly  been  taken  from  a  rich  chimney 
in  a  6-foot  quartz-vein  at  this  mine.  The  old  shaft  was  continued  to  a 
depth  of  102  feet,  and  the  ore-shoot  found  to  pinch  out.  Assays  from 
the  lower  end  of  the  chimney  ran  about  $4  per  ton.  There  are  no  sul- 
phurets  to  speak  of  in  the  ore  at  this  depth.  The  country-rock  (mica- 
ceous schist)  is  slightly  auriferous  in  places.  It  is  stated  that  large 
areas  of  the  saprolites  will  yield  18  cents  per  cubic  yard.  Sufficient 
water-supply  for  hydraulicking  or  sluicing  is  difficult  to  obtain. 

GOLD   MINES   IN   VIRGINIA. 

The  principal  gold  region  of  this  State  is  comprised  in  the  Virginia 
belt  (see  p.  13).  A  small,  isolated  area  of  placer  deposits  is  situated  on 
the  west  side  of  the  Blue  Ridge  in  Montgomery  and  Floyd  counties. 

1  Unless  otherwise  stated,  the  mines  are  not  at  present  working-.  The  values  of  the  ores  are 
not  given  on  our  authority ;  the  same  is  true  of  the  dimensions  of  the  ore  bodies  in  abandoned 
mines,  and  in  such  as  could  not  be  examined. 

2  The  best  description  of  these  mines  has  been  given  by  Mr.  S.  F.  Emmons,  in  a  paper  entitled 
"Notes  on  the  Gold-Deposits  of  Montgomery  County,  Maryland,"  Trans.  Am.  Inst.  Min. 
Enqs.,  xviii,  1890,  pp.  391  to  412. 


72  GOLD    MINING    IN    VIRGINIA. 

So  far  as  is  known,  none  of  the  Virginia  mines  are  at  present  working 
on  an  actively  producing  scale,  although  considerable  prospecting  is  in 
progress  and  apparent  preparations  for  mining  are  being  made. 

The  mines  of  Fauquier,  Stafford,  Culpeper,  Orange  and  Spottsyl- 
vania  counties  are  grouped  around  the  junction  of  the  Rappahannock 
and  Rapidan  rivers  in  a  belt  some  15  miles  wide. 

MINES    IN    FAUQUIER    COUNTY. 

The  Franklin,  Wycoff  and  Leopold  mines  are  situated  in  the  southern 
part  of  the  county  near  Morrisville. 

MINES    IN    STAFFORD    COUNTY. 

The  principal  localities  are  in  the  western  part  of  the  county  near  the 
Rappahannock  river.  The  Eagle  mine,  situated  12  miles  northwest  of 
Fredericksburg,  was  worked  by  the  Rappahannock  Gold  Mining  Com- 
pany in  1894;  greatest  depth,  250  feet;  length  of  workings,  600  feet. 

The  Monroe  mine  adjoins  the  Eagle  on  the  northwest,  and  the  Lee 
mine  is  situated  in  the  same  vicinity. 

The  Rattlesnake  mine  adjoins  the  Eagle  on  the  northwest.  It  was 
worked  as  a  gulch  placer;  large  amounts  of  nuggets  are  reported,  weigh- 
ing from  -J  to  5  dwts. ;  some  as  high  as  125  dwts. 

MINES  IN  CULPEPER  COUNTY. 

The  Culpeper  mine  is  situated  18  miles  west  of  Fredericksburg  on 
the  Rapidan  river.  Prof.  Silliman  (in  a  report  made  in  1836)  stated 
the  average  value  of  this  ore  to  be  $25  per  ton,  and  the  mining  and 
milling  expenses  at  $7  per  ton.  Other  mines  in  the  district  are  the 
Richardville  and  the  Ellis. 

The.  Powhatan  Land  and  Mining  Company  operated  a  mine  in  this 
county  in  1894,  treating  the  ore  in  Crawford  mills  and  a  ten-stamp  mill 
(Fraser  and  Chalmers'  make)  in  connection  with  Frue  vanners. 

mines  in  spottsylvania  county. 

The  oldest  mines  worked  in  this  county  were  those  operated  by  the 
United  States  Mining  Company  near  the  Rappahannock  river  in  the 
extreme  northwest  corner  of  the  county.  A  description  of  the  method 
of  milling  at  these  mines  in  1835  is  given  on  p.  33.  At  that  time  a 
2 -foot  vein  was  operated  by  adits  and  several  shafts,  the  deepest  of 
which  was  80  feet.  The  value  of  the  ore  is  given  in  this  early  report  at 
$25  per  ton,  and  the  cost  of  milling  at  80  cents  per  ton.  Other  old 
mines  near  this  property  are  the  Marshall  and  the  Gardiner. 


£ 


DISTRIBUTION   OF  GOLD   MINES   IN   THE   SOUTH  APPALACHIAN  REGION.     73 

In  the  central  portion  of  the  county  there  is  a  group  of  mines,  most 
prominent  among  which  is  the  Whitehall,1  which  was,  in  active  operation 
as  late  as  1884.  Other  properties  in  this  group  are  the  Kiggins,  Johns- 
ton, Pnllian  and  Grindstone  Hill  mines. 

Still  farther  south  are  the  Mitchell  and  the  Goodwin  mines.  They 
are  located  on  Pigeon  run,  along  which  considerable  placer-work  was 
done  in  the  earlier  days.  Both  have  been  worked  within  the  past 
twelve  years,  but  no  paying  vein  was  developed. 

MINES    IN    ORANGE    COUNTY. 

The  gold  mines  of  this  county  are  situated  in  the  northeast  corner 
near  the  Rapidan  river.  The  most  prominent  one  among  them  is  the 
Vaucluse,  which  was  discovered  and  opened  in  1832.  A  description  of 
the  milling  practice  at  this  mine  in  1847  is  given  on  p.  34.  Other 
mines  in  the  vicinity  are  the  Orange  Grove,  Greenwood  and  Melville. 

MINES  IN  LOUISA  COUNTY. 

The  gold-bearing  rocks  traverse  the  central  portion  of  the  county  in 
a  southwesterly  direction,  forming  a  narrow  belt  but  a  few  miles  in 
width.  In  this  belt,  near  the  centre  of  the  county,  and  from  2  to  6 
miles  northeast  of  Mineral  City  (Tolersville),  are  the  Louisa  county 
pyrite  mines.  These  large  bodies  of  sulphurets,  occurring  in  lenses  with 
a  maximum  thickness  of  60  feet,  and  developed  to  a  depth  of  over  600 
feet,  are  probably  of  contemporaneous  origin  with  the  gold-veins.  They 
show  the  same  strike  (N.  30°  E.),  dip  (60°  S.E.)  and  pitch  of  shoots  or 
ore  lenses  (45°  E".E.)  as  the  quartz-veins  in  the  vicinity.  Traces  of  gold 
are  found  in  the  pyrite  deposits,  and  small  gold-bearing  quartz-veins 
have  been  encountered  in  the  mines.  We  quote  from  a  letter  written 
by  Mr.  W.  H.  Adams,  manager  of  the  Arminius  Pyrite  Mines,  Mineral 
City,  to  whose  kindness  we  are  much  indebted: 

"  It  is  true  that  in  the  pyrite  vein,  as  now  opened,  there  are  traces  of  gold 
and  silver,  but  I  do  not  think  the  average  so  high  as  $1.00  per  ton,  and  have 
found  that  gold  carries  only  in  certain  lines,  and  that  nearly  all  the  vein  matter 
is  barren.  There  are,  in  all  of  the  properties,  easily  traceable  quartz-veins  in 
the  hanging-  and  foot-slates,  which  are  gold-bearing  to  the  extent  of  $4.00  to 
$15.00  per  ton,  but  these  veins  are  always  narrow — about  as  you  saw  them 
in  our  No.  3  shaft  (3  to  7  inches).  They  are,  however,  persistent,  and  I  have 
no  doubt  that  chimneys  are  to  be  found  at  points  of  contact  of  the  veins  and 
dikes,  which  chimneys  will  be  found  to  be  the  source  of  much  of  the  gold  so 
prevalent  in  the  streams  of  the  neighborhood." 

The  scope  of  this  report  will  not  permit  a  detailed  description  of  these 
interesting  pyrite  deposits  or  the  methods  of  mining  and  concentration 

1  See  Am.  Jour.  Sci.,  i,  xxxii,  1837,  p.  101. 


'"- 


74  GOLD    MINING    IN    VIRGINIA. 

pursued  here.1  It  may,  however,  be  of  value  to  give  the  cost  of  labor 
at  these  mines,  as  this  would  apply  equally  to  auriferous  mining.  The 
daily  wages  paid  are: 

Carpenters    $1.25  to  $1.75 

Engineers    1.40 

Blacksmiths    1.30  to     1.75 

Drill-runners    1.35 

Helpers    1.20 

General  labor  (under  ground)  1.00 

"      (above  ground)    0.90  to  1.00 

The  Tinder  Flats  placer  deposits  '  are  situated  at  the  northern  end  of 
the  pyrite  bodies  on  both  banks  of  JSTorth  Contrary  creek. 

This  bottom  was  perhaps  the  best  known  and  most  productive  source 
of  placer-gold  in  the  early  days  of  Virginia  gold-mining. 

At  present  the  problem  is  one  of  reworking  shallow  placer  bot- 
toms on  a  large  scale,  and  at  the  time  of  our  visit  in  1895,  Mr.  W.  H. 
Case,  of  Charlotte,  ~N.  C,  was  testing  the  ground  with  this  object  in  view. 
Water  under  natural  head  cannot  be  obtained  here,  the  surrounding 
country  being  a  but  slightly  indented  pene-plain  it  would  probably 
have  to  be  pumped  from  the  North  Anna  river. 

One-half  mile  southwest  of  the  Arminius  pyrite  mine,  on  the  same 
line  of  strike,  is  the  Walton  gold  mine.  This  mine  has  produced  some 
very  rich  ore  from  a  shoot  or  chimney  developed  to  a  depth  of  150  feet. 
The  property  has  been  tied  up  in  litigation  for  the  past  twelve  years. 

Near  Mineral  City  (Tolersville)  a  vein,  known  as  the  Fisher  Lode, 
striking  parallel  to  the  pyrite  veins  and  about  2  miles  to  the  east  of 
them,  has  been  opened  by  the  Harris,  Luce,  Slate  Hill,  Louisa  and 
Warren  Hill  mines.  Two  of  these,  the  Luce  and  Slate  Hill,  were  in 
operation  at  the  time  of  our  visit. 

The  Luce  mine  had  been  developed  to  a  depth  of  200  feet,  and  the 
total  length  of  drifting  on  the  vein  is  over  1000  feet.  The  thickness 
of  this  vein  is  from  3  to  8  feet.  The  mine  is  equipped  with  a  20-stamp, 
hand-feed  mill  (Fraser  and  Chalmers'  build). 

The  Slate  Hill  mine  was  first  opened  in  1850,  and  for  a  time  was 
extensively  worked.  It  is  the  southwest  extension  of  the  Luce,  which 
formerly  constituted  a  portion  of  the  property.  Two  veins  are  devel- 
oped to  a  depth  of  150  feet.  In  a  report  made  in  1853,  the  average 
value  of  the  ore  is  given  at  $4  per  ton,  and  the  cost  of  mining  and  mill- 
ing at  $1.40  per  ton.  The  present  company  began  operations  in  March, 
1895.  A  Huntington  mill  has  been  erected,  and  the  mine  was  being 
developed  in  the  lower  levels  at  the  time  of  our  visit. 

1  For  a  description  of  the  deposits,  see  "  Origin  of  the  Iron  Pyrites  Deposits  in  Louisa  County. 
Virginia,"  by  Frank  L.  Nason ;  Eng.  and  Min.  Jour.,  Ivii,  1894,  pp.  414-16. 

2  See  Am.  Jour.  Sci.,  i,  xxxii,  1837,  pp.  101,  110. 


DISTRIBUTION  OF   GOLD   MINES   IN  THE   SOUTH  APPALACHIAN   REGION.     75 
MINES    IN    FLUVANNA    AND    GOOCHLAND    COUNTIES.1 

The  same  narrow  belts  traverse  the  boundary  of  Goochland  and 
Fluvanna  counties,  crossing  the  James  river  at  Bremo  Bluffs  into  Buck- 
ingham county.  ~No  work  but  petty  placer-mining  and  more  or  less 
active  prospecting  is  carried  on  in  these  counties  at  present,  although 
from  1830  to  1860  this  region  was  the  field  of  extensive  operations. 

Among  the  well  known  properties  are  the  Tellurium,  the  Bowles,  the 
Payne,  the  Page,  the  Hughes,  the  Moss,  the  Fisher,  the  Busby,  the 
Tagus,  the  Gilmore,  the  Collins,  Marks,  Fades,  Big  Bird  and  the 
Belzora. 

The  Tellurium  mine,  embracing  a  property  of  644  acres,  lies  partly 
in  Fluvanna  and  partly  in  Goochland  county,  6  miles  from  Columbia, 
and  is  at  present  owned  by  the  Columbia  Gold  Mining  Company.  It 
was  discovered  in  1834  by  George  Fisher,  and  is  reported  to  have  yielded 
$1,000,000  during  its  various  periods  of  activity.  It  was  last  operated 
in  1886.  Three  principal  parallel  veins,  the  " :  Sandstone,"  "  Middle  " 
and  "  Little,"  traverse  the  property  in  a  southwesterly  direction  for  a 
distance  of  about  half  a  mile.  None  of  the  workings  have  extended 
below  a  depth  of  60  feet. 

The  Bowles  mine  adjoins  the  Tellurium,  and  the  Payne  mine  is  in 
the  same  vicinity. 

Lying  partly  in  Fluvanna  and  partly  in  Goochland  county,  and  within 
\  mile  of  the  Tellurium  and  Bowles  mines  are  the  Fisher,  the  Moss  and 
the  Busby  mines,  all  on  the  same  lode. 

The  Fisher  mine  was  opened  in  1860  by  James  Fisher.  The  main 
developments  consist  of  a  40-foot  shaft  with  175  feet  of  levels.  The 
vein  is  narrow,  from  3  to  15  inches,  and  the  ore  is  stated  to  carry  from 
$25  to  $300  per  ton. 

The  Moss  mine  is  one  mile  northeast  of  the  Fisher.  It  was  discovered 
in  1835  by  John  Moss.  It  has  been  worked  to  a  depth  of  65  feet,  and 
the  vein,  which  is  2  feet  wide  in  places,  carries  reported  values  of  $15  to 
$65  per  ton.      ^ 

The  Busby  mine  is  one-half  mile  northeast  of  the  Moss.  Prof.  Silli- 
man,  in  an  early  report,  gives  ore  values  of  $160  per  ton  from  here. 
The  work  has  been  altogether  of  a  superficial  nature. 

The  Page  mine  is  situated  \  mile  west  of  Wilmington  on  Long  Island 
creek  in  Fluvanna  county.  Work  was  begun  on  the  quartz-veins  in 
1856,  when  an  8-stamp  mill  was  erected.  Considerable  prospecting 
work  has  been  carried  on  lately. 

The  Hughes  mine  is  5  miles  from  Bremo  Bluffs  in  Fluvanna  county. 

1  We  beg  to  acknowledge  our  indebtedness  to  Messrs.  Wm.  Bugbee  and  Scott  Thurston  ot 
Palmyra,  Va.,  for  information  concerning  the  mines  of  these  counties. 


I  6  GOLD    MINING    IN    SOUTH    CAROLINA. 

It  was  opened  in  1836.     The  last  work  was  done  about  4  years  ago,  when 
a  60  -foot  shaft  was  sunk,  but  without  encouraging  results. 

The  Belzoea  mine  is  7  miles  from  Columbia  in  Goochland  county. 
It  was  discovered  in  1832,  and  was  worked  by  surface  washing  until 
1849,  and  after  that  the  veins  were  opened.  The  Marks,  Collins, 
Eades  and  Big  Bird  mines  adjoin  the  Belzora. 

MINES    IN    BUCKINGHAM    COUNTY. 

This  is  the  most  southwesterly  county  of  the  Virginia  gold  belt  in 
which  mines  have  been  actively  operated.  The  occurrence  of  gold  has, 
however,  been  reported  still  farther  to  the  southwest,  in  Appomattox, 
Prince  Edwards,  Charlotte,  and  Halifax  counties. 

The  Booker,  mine,  near  Whitehall  Station,  was  worked  prior  to  1860 
by  an  English  company.  The  deepest  shaft  is  110  feet.  The  ore  was 
crushed  in  a  Howland  mill  and  yielded  $13  per  ton. 

Another  English  company  operated  the  London  mine,  seven  miles 
north  of  the  Booker,  for  a  number  of  years.  Other  mines  of  equal 
importance  in  their  day  are  the  Garnett  and  Mosely  (3  miles  west  of 
Willis  mountain),  the  Buckingham,  the  Morton,  the  Morrow,  the  Dun- 
can, the  Ford,  and  the  Lightfoot. 

MINES    IN    FLOYD    AND    MONTGOMERY    COUNTIES. 

A  small  placer-mining  field  was  opened  here  (on  the  west  side  of 
the  Blue  Ridge)  in  1879,  along  Brush  and  Laurel  creeks  and  other 
small  streams  running  from  Pilot  mountain.  The  area  embraces  about 
80  square  miles. 

The  Walters  and  Gardner  mine  in  Montgomery  county  was  operated 
in  1893. 

Gold  also  occurs  it  Patrick,  Carroll  and  Grayson  counties,  but  prob- 
ably only  to  a  very  limited  extent,  associated  with  copper  ores. 

GOLD  MINES  IN  SOUTH  CAROLINA. 

The  present  gold  output  of  South  Carolina  is  derived  almost  entirely 
from  the  Haile  mine. 

To  show  the  extent  and  distribution  of  the  gold-mining  industry  in 
South  Carolina  before  the  war,  the  following  table  comprising  the  work- 
ing mines  in  1859  is  given: 1 

Chesterfield  and  Lancaster  counties 21  working  mines. 

Spartanburg,  Union    and  York  counties 19 

Abbeville  and  Edgefield  counties 10         "  " 

Greenville  and  Pickens  counties S         "       placers. 

Total  in  State 5S 

1South  Carolina.    Resources,  etc.,  published  by  the  State  Board  of  Agriculture,  Charleston, 
1883,  p-  134. 


DISTRIBUTION  OF   GOLD   MINES   IN  THE    SOUTH  APPALACHIAN   REGION.     'I  ( 

Some  of  these  were  probably  minor  operations,  as  Lieber1  in  his 
reports,  made  a  few  years  earlier,  complained  of  the  lack  of  interest  taken 
in  the  South  Carolina  gold  mines. 

CAROLINA    BELT. 

Chesterfield  County. — The  Brewer  mine  is  the  main  point  of  in- 
terest in  this  county.     It  is  fully  described  on  p.  144. 

In  the  same  neighborhood  are  the  old  Kirkley,  Leach  and  Mclnnis 
mines.  Some  gravel  mining  has  been  done  near  the  northern  boundary 
of  this  county. 

Lancaster  County. — The  Haile  mine  is  fully  described  on  p.  125. 
The  Funderburk,  8  miles  northeast  of  the  Haile,  and  of  the  same  char- 
acter, was  worked  as  late  as  188 7.  The  Clyburne  property  is  situated 
1J  miles  southwest  of  the  Haile.  Some  tributing  is  done  here  with 
rockers,  on  saprolite  and  gulch  deposits.  Adjoining  this  on  the  south- 
west is  the  Gay  mine,  which  shows  ore-bodies  of  the  Haile  type,  but  is 
little  developed.  The  most  southerly  occurrence  of  gold  in  this  district 
is  at  the  Williams  mine,  7  miles  southwest  of  the  Haile. 

York  County. — There  is  no  active  work  at  present  in  this  county. 
Among  the  older  mines  of  this  district  are  the  Wilson,  Wallace  and 
Palmetto. 

Union  County. — About  3  miles  south  of  Glen  Springs  are  the  West 
and  the  Thomson  mines.  Mr.  Becker  describes  the  veins  as  quartz 
lenses  similar  to  the  Dahlonega  type,  interlaminated  with  mica-  and 
hornblende-schists.  The  Thomson  mine  was  operated  during  the  sum- 
mer of  1895  on  a  small  scale  by  the  Dahlonega  method  of  mining  and 
milling. 

Abbeville  and  Edgefield  Counties. — Little  information  could  be 
obtained  regarding  the  mines  of  this  district.  The  deposits  are  probably 
closely  connected  with,  and  of  the  same  nature  as  those  in  McDuffie, 
Warren  and  Columbia  counties,  Ga.  The  Dorn  mine,  situated  at  the 
loAver  end  of  the  Abbeville  district,  was  opened  in  1852.  In  the  first 
year  of  its  operation  over  $300,000  are  said  to  have  been  taken  from  a 
rich  pocket  in  this  mine;  a  yield  of  $100  per  ton  was  considered  a  poor 
one.  The  rich  pockets  were,  however,  soon  exhausted;  and  the  mine 
was  abandoned  until  1866,  when  it  was  reworked  for  a  short  time  with 
some  success,  as  reported. 

SOUTH    MOUNTAIN    BELT. 

Spartanburg,  Greenville  and  Pickens  Counties. — The  gold  dis- 
trict in  these  three  Piedmont  counties  is  probably  a  continuation  of  the 

1  For  a  full  discussion  of  the  occurrence  of  g-old  and  a  description  of  the  older  mines  in  South 
Carolina,  see  Tuomey  (M.),  Report  on  the  Oeoloqy  of  South  Carolina,  1848;  and  Lieber  (O.  M.). 
Reports  on  the  Survey  of  S.  C,  1856,  1857, 1858  and  1859. 


7  b  GOLD    MINING    IN    GEORGIA. 

South  Mountain  'belt  in  ^orth  Carolina  (page  68),  and,  as  in  that  dis- 
trict, the  gold  produced  has  been  obtained  almost  entirely  from  placer- 
deposits.  The  present  operations  are  purely  of  a  desultory  character. 
Among  the  more  extensive  deposits  might  be  mentioned  those  of  "Wolfe 
creek  and  Tiger  river,  located  on  the  boundary  between  Spartanburg 
and  Greenville  counties  at  the  foot  of  Hogback  mountain.  The  gold  in 
these  bottoms  is  derived  from  small  quartz-veins  having  the  same  strike 
and  dip,  and  being  in  other  respects  similar  to  those  of  the  South  Moun- 
tain district  in  North  Carolina.  The  gravel  in  the  bottom  is  from  a  few 
inches  to  5  feet  in  thickness.  It  consists  of  white,  saccharoidal  and 
glassy,  barren  quartz.  In  1892  the  Wolfe  creek  bottom  was  worked  by 
the  Wolfe  and  Tiger  Mining  Company,  with  a  2-inch  nozzle  giant, 
supplied  with  45  feet  head  of  water  by  a  4-mile  ditch. 

Other  mining  properties  in  this  vicinity  are  the  Hammett,  Knott, 
Golden  Gate,  Thompson,  Hale  and  \\Test  Springs. 

GOLD   MINES   IN   GEORGIA.1 

MINES    IN    RABUN    COUNTY. 

Some  work  has  been  done  at  the  Smith  mine  near  Burton,  and  at  the 
Moore  Girls'  mine,  12  miles  northwest  of  Clayton. 

MINES  IN  HABERSHAM  COUNTY. 

Practically  no  work  of  importance  has  been  done  in  this  county, 
excepting  perhaps  some  development  work  a  few  miles  northeast  of 
Clarkesville. 

MINES    IN    WHITE    COUNTY. 

The  chief  mining  district  is  located  in  the  picturesque  Xacoochee 
valley  and  its  vicinity.  Among  the  many  Indian  traditions  of  this 
neighborhood  is  that  of  extensive  gold  mining  by  the  aborigines,  but 
absolute  proof  of  this  is  wanting. 

The  Lumsden  mine  is  situated  about  2  miles  north  of  the  Nacoochee 
valley  on  Bean  creek.  Several  rich  quartz-stringers  were  being  worked 
in  1895  by  tributors,  using  a  combination  of  hydraulic  and  dry  mining, 
the  hard  ore  being  hauled  £  mile  to  a  wooden  10-stamp  mill,  driven  by 
a  20-foot  over-shot  water-wheel.  Five  hands  are  stated  to  extract  70 
to  80  dwts.  per  week  by  this  crude  method. 

The  J arret  mine  adjoins  the  Lumsden  on  the  south;  a  20-stamp- 
mill  was  operated  here  for  some  time  by  Mr.  Childs,  of  Athens,  Ga., 

1  For  a  more  complete  statement  concerning  gold  mines  and  mining  in  Georgia  see  Bulletin 
No.  2  of  the  Georgia  Geological  Survey,  Atlanta,  Ga. 


DISTRIBUTION  OF   GOLD   MINES   IN   THE    SOUTH   APPALACHIAN   REGION.     79 

using  the  Dahlonega  method  of  sluicing  and  milling  (see  p.  107).  It  has 
been  idle  for  the  past  eight  or  nine  years. 

The  Yonah  Land  and  Mining  Company  controls  some  4800  acres  of 
mining  property  situated  mainly  along  the  watershed  of  Dukes  creek. 
This  property  is  a  consolidation  of  what  was  formerly  known  as  the 
Tonton,  the  Mercer  and  the  Butt  mines.  The  company  has  pursued 
extensive  vein  explorations  on  their  land  under  the  direction  of  Mr.  E. 
T.  Whatley.  This  prospecting  work  has  disclosed  a  large  number  of 
auriferous  quartz-veins,  which  have  a  general  strike  of  N.  20°  E.  and  a 
dip  of  about  85°  S.E.,  while  the  dip  of  the  country-rock  is  steeply  to 
the  E\"W.  Although  of  low  grade  ($3  to  $7  per  ton)  and  of  small  width 
(6  inches  to  3  feet),  some  of  these  veins  might,  under  close  management, 
be  mined  and  milled  at  a  profit.  The  producing  operations  of  this  com- 
pany are  confined  to  placer  work  with  hydraulic  elevator  in  the  bottom 
land  of  Dukes  creek.  The  elevator  used  and  the  method  of  work  in 
the  pits  is  similar  to  that  employed  by  the  Chestatee  Company  (see 
p.  101).  A  65-foot  head  of  water  is  obtained  from  a  7-mile  ditch  line. 
The  gravel  bed  averages  about  3  feet  in  thickness,  covered  by  6  inches 
of  peat  and  clay,  and  above  this  about  6  feet  of  soil  overlay.  The  gold 
consists,  to  a  large  extent,  of  extremely  rounded  and  water  worn  nuggets, 
often  aggregated  in  pockets,  from  one  of  which  $1500  is  reported  to 
have  been  taken  in  one  day. 

The  Loud  mine,  situated  near  Pleasant  Retreat  P.  O.,  and  about  11 
miles  east  of  Dahlonega,  is  one  of  the  famous  placers  of  the  district, 
and  has  produced  a  large  amount  of  remarkably  well  crystallized  and 
wiry  nugget  gold.  It  has  been  known  as  one  of  the  most  extensive 
and  richest  deposits  in  the  Southern  States.  For  the  past  few  years 
the  work  has  been  confined  to  hydraulicking  old  gravel  piles.  Water, 
under  a  75-foot  head,  is  leased  from  the  Hand-Barlow  Company  of  Dah- 
lonega and  is  supplied  by  a  ditch  25  miles  in  length.  Extensive  cuts  in 
the  saprolites  have  been  made  here. 

Other  properties  of  importance  in  White  county  are  the  Longstreet 
placer,  2-J  miles  northwest  of  Cleveland,  the  Nacoochee  Hills  Gold 
Mining  Company,  the  Martin  Mining  Company,  the  St.  George  prop- 
erty (also  known  as  the  Dean  Mine),  the  Plattsburg  (or  Chattahoochee) 
Gold  Mining  and  Milling  Company,  etc. 

Besides  these  there  are  quite  a  number  of  petty  operators,  some  wash- 
ing gravel  in  sluice  boxes,  others  mining  rich,  narrow  seams  in  the 
saprolite  and  "  beating  "  the  ore  in  wooden  stamp-mills,  as,  for  instance, 
at  the  Thompson  mine  near  the  Yonah  Land  Company's  property, 
where  the  mining  operations  were  formerly  carried  on  by  a  mother  and 
son,  the  latter  digging  the  quartz  and  carrying  it  on  his  back  to  the 
mill,  while  his  mother  attended  to  the  beating. 


IB 


1 


S 


so 


GOLD    MINING    IN    GEORGIA. 


MINES    IN    HALL    COUNTY. 


But  little  active  work  has  been  in  progress  for  a  number  of  years. 
The  principal  properties  are  the  Botosi,  12  miles  northeast  of  Gaines- 
ville, the  Currahee,  6  miles  northeast  of  Gainesville,  the  Elrod,  the 
Merrick,  the  Mammoth  and  the  Glades.  The  Currahee  mine  is 
equipped  with  a  20-stamp  mill  and  a  roasting  furnace.  The  ore  is 
quartz,  containing  pyrite  and  galena.  A  set  of  rolls  and  a  cyanide  plant 
are  now  being  erected  at  this  mine. 

MINES    IN    LUMPKIN    COUNTY. 

The  principal  mining  operations  are  in  the  vicinity  of  Dahlonega, 
extending  from  the  Yahoola  river,  about  1  mile  northeast  of  the  town, 
in  a  continuous  belt  nearly  4  miles  in  width  to  the  mining  village  of 
Auraria  (Kunckelsville),  a  total  length  of  about  6  miles.  A  general 
description  of  this  belt  and  the  method  of  mining  and  milling  (which 
bears  the  name  of  the  Dahlonega  or  Georgia  method)  pursued  here  is 
given  on  page  107. 

This  is  by  all  means  the  most  important  mining  district  in  Georgia. 
In  1838  a  United  States  mint  was  established  in  Dahlonega,  which  con- 
tinued in  active  operation  until  1861,  during  which  time  $6,106,569 
were  coined.  The  nearest  railroad  point  to  Dahlonega  is  Gainesville 
(Southern  B.  B.),  20  miles  to  the  southeast.  A  connecting  branch  be- 
tween these  two  points  is  looked  for  in  the  near  future,  and  will  greatly 
benefit  the  mining  interests  of  the  district. 

The  following  is  a  list  of  the  prominent  mines  and  their  crushing 
equipment:  Mary  Henry  (or  Murray)  (5  stamps);  Hand  (20  stamps); 
Singleton  (10  stamps);  Yahoola  (20  stamps);  Stanley  (10  stamps): 
Findley  (40  stamps);  Preacher  (10  stamps);  Hedwig  (40  stamps); 
Josephine  (20  stamps);  Lockhart  (20  stamps);  Barlow  (40  stamps); 
Balston  (20  stamps);  Turkey  Hill  (10  stamps);  Woodward  (5  stamps); 
Ivy  (60  stamps);  Calhoun  (40  stamps);  Garnet  (20  stamps);  Bigley 
(20  stamps);  Fish  Trap  (20  stamps);  Bast  (10  stamps);  Siloam  (^10 
stamps);  Lawrence  (10  stamps);  Horner  (5  stamps);  Betz  (1  Hunting- 
ton mill).  In  the  summer  and  fall  of  1896  240  stamps  were  being 
operated  at  the  Bindley,  Hand,  Yahoola,  Murray,  Lockhart,  Singleton, 
Woodward,  Breacher,  Turkey  Hill,  Balston,  Barlow  and  Hedwig  mines. 

Of  late  years  more  attention  is  being  paid  to  the  deep-mining  of  hard 
ore  in  distinction  to  the  usual  method  in  this  district  of  sluicing  the  soft 
saprolites.  Thus,  at  the  Lockhart  mine,  quartz  from  underground 
stopes  is  treated  in  a  20-stamp  mill  (for  description  of  which  see  p.  115). 

The  special  operations  of  the  Chestatee  Company,  and  of  the  dredge 
boats  on  the  Chestatee  river,  are  described  on  pages  101,  106. 


DISTEIBUTION  OF  GOLD  MINES  IN  THE  SOUTH  APPALACHIAN  REGION.    81 

Among  the  mines  of  this  district  there  are  some  that  are  operated 
by  lessees,  and  in  those  cases  the  usual  royalty  is  25  per  cent,  for  prop- 
erties on  which  a  mill  and  water-power  are  furnished,  and  10  per  cent, 
where  these  are  absent. 

MINES    IN    DAWSON    COUNTY. 

At  present  no  active  work  of  any  prominence  is  prosecuted.  Among 
the  mines  formerly  extensively  operated  by  the  Dahlonega  method  may 
be  mentioned  the  Cincinnati  Consolidated,  the  Etowah,  the  Kin-Mori 
and  the  McGuire,  all  situated  in  the  vicinity  of  Dawsonville,  the  county 
seat. 

At  the  Kin-Mori  a  ditch  34  miles  in  length,  delivering  600  to  700 
inches  at  a  pressure  of  286  feet,  was  completed  in  1883,  and  placer- 
mining  on  an  extensive  scale  was  carried  on  in  connection  with  a  Hendy 
gravel  elevator.  A  30-stamp  mill  was  erected  during  the  winter  of 
1884-85.     The  mine  has  been  idle  since  1888. 

MINES    IN    FORSYTHE    COUNTY. 

No  mines  of  importance  have  been  developed,  the  gold  output  having 
been  derived  almost  solely  from  small  placer-diggings.  The  Dr.  Charles 
property,  which  is  6  miles  southwest  of  Dawsonville,  and  not  far  from 
the  Cherokee  county  line,  has  been  prospected  to  some  extent.  The 
quartz-veins  carry  arsenical  pyrites  from  the  grass  roots  down,  and  very 
little  ordinary  pyrites.     There  is  a  10-stamp  mill  at  this  mine. 

Other  properties  that  might  warrant  attention  are  the  Little,  Settles, 
Collins,  Sawnee  Mt,,  Parks,  and  Fowler. 

MINES    IN    GWINNETT    COUNTY. 

The  Piedmont  mine,  2  miles  northeast  of  Buford,  has  been  worked 
in  a  small  way  until  recently.  The  vein-quartz  carries  pyrite,  galena, 
and  free  gold. 

The  Shelby  mine  is  4  miles  west  of  Buford.  It  is  equipped  with  a 
5-stamp  mill.  The  quartz-vein  is  2  feet  in  width,  and  is  stated  to 
carry  values  approximating  $6  per  ton.  The  Simmons  property  adjoins 
the  Shelby  on  the  east. 

MINES  IN  CHEROKEE  COUNTY. 

At  Creighton,  near  the  eastern  boundary  of  this  county,  is  located  the 
Creighton  (Franklin)  mine,  which,  together  with  the  Haile  mine  of 
South  Carolina,  and  some  smaller  mines  in  North  Carolina,  shows 
the  brighter  side  of  Southern  gold-mining.  It  is  a  continuously 
and  systematically  worked,  dividend-payina'  property  (for  description 
6 


82  GOLD    MINING    IN    GEORGIA. 

see  p.  121).  Stimulated  by  the  success  of  this  mine,  developments  are 
being  pushed  on  several  other  properties  in  this  county,  mainly  along  the 
approximate  strike  of  the  Franklin  vein.  The  properties  extend  from 
a  point  about  3  miles  north  of  the  Creighton,  in  a  more  or  less  continuous 
line  to  the  Sixes,  Wilkinson,  Cherokee  (10  stamps),  Georgiana,  Cox  and 
Worley  mines  in  the  southwestern  portion  of  the  county.  Xear  the 
center  of  this  belt,  south  of  the  Creighton,  the  Chester  (formerly 
Latham)  and  the  Strickland  properties  have  been  prospected. 


The  same  auriferous  belt,  described  above  as  occurring  in  Cherokee 
county,  extends  through  a  portion  of  Barton,  Cobb  and  Paulding  coun- 
ties. In  the  latter  county  a  high-grade  quartz-vein  has  been  opened  up 
in  the  Yorkville  mines. 

In  Douglas  county,  lenses  of  auriferous  quartz  have  been  explored 
to  some  extent  in  former  years,  but  no  active  mining  is  carried  on  at 
present. 

The  Mineral  Hill  mine  in  this  county  has  been  developed  by  a 
double-compartment  shaft  120  feet  in  depth,  sunk  on  the  vein.  At  the 
80-foot  level  the  width  of  the  ore-body  is  estimated  to  be  15  feet.  The 
ore  is  rich  in  sulphur ets  (pyrite  and  chalcopyrite),  and  is  stated  to  have 
an  average  value  of  $8  per  ton. 

MINES    IN    CARROLL    COUNTY. 

The  principal  mining  district  is  in  the  vicinity  of  Villa  Rica,  where 
prospecting  and  development  work  has  been  quite  active  during  recent 
years.  The  principal  properties  are  the  Clopton  mine,  operated  by  the 
Boston  Kennesaw  Mining  Company;  the  Mineral  Farm  mine,  3^  miles 
northwest  from  Villa  Rica;  the  Pine  Mountain  mine,  operated  by  the 
Southern  States  Exploration  and  Financial  Syndicate,  L't'd. 

MINES  IN  HARALSON  COUNTY. 

Several  mines  have  been  opened  in  the  southwestern  portion  of  this 
county,  lying  in  the  belt  which,  to  the  southwest,  is  more  extensively 
developed  near  Arbacoochee,  Ala.  The  most  important  of  these  is  the 
Royal  (formerly  known  as  the  Camille)  mine,  2-J  miles  southwest  of 
Tallapoosa. 

In  past  years  the  soft,  semi-crystalline  slates  were  sluiced,  the  loose 
free  gold  saved  in  the  sluice  boxes,  the  quartz  milled,  and  the  gold  saved 
by  amalgamation.  In  the  washed-off  portion,  hundreds  of  quartz- 
stringers,  from  the  size  of  a  knife  blade  to  5,  6  and  more  feet  in  thick- 
ness, can  be  seen  striking  almost  due  east  and  west. 


DISTRIBUTION  OF   GOLD   MINES   IN   THE   SOUTH  APPALACHIAN   REGION.     83 

In  1887  a  large  amount  of  money  was  spent  in  developing  the  mine 
and  in  erecting  a  20-stamp  mill  (Fraser  and  Chalmers),  with  8  Frue 
vanners.  A  double-compartment  inclined  shaft  was  sunk  to  a  depth  of 
186  feet.  The  ore  was  milled  at  the  rate  of  4  tons  per  stamp  head. 
But  little  free  gold  was  saved,  the  loss  in  the  sulphurets  being  great, 
and  after  a  short  run  the  work  was  abandoned  as  unprofitable. 

In  December,  1895,  Capt.  A.  Thies,  of  the  Haile  mine,  S.  C,  made 
a  thorough  examination  of  this  property,  which  resulted  in  reworking 
the  mine  and  the  erection  of  a  chlorination  plant. 

The  outcrop  of  the  main  vein,  on  which  the  186-foot  shaft  is  sunk, 
is  exposed  for  600  feet  west  of  the  shaft.  The  width  of  the  ore-body 
is  stated  to  be  6  feet.  The  ore  in  sight  stands  practically  from  the  186- 
foot  level  to  the  surface,  and  is  developed  by  east  and  west  drifts. 

Later,  a  three-compartment  vertical  shaft  was  located  south  of  the 
inclined  shaft  and  sunk  to  a  depth  of  118  feet.  It  cut  the  ore-body  at 
105  feet  and  had  not  passed  through  it  at  118.  The  ore  is  hard,  white 
quartz,  heavily  sulphuretted. 

In  the  original  exploratory  work  done  by  Capt.  Thies,  8  tons  of  ore, 
including  a  large  amount  of  hanging  wall  slates  broken  from  the  east 
drift  of  the  inclined  shaft,  were  milled  and  yielded  55  dwts.  free  gold 
and  ^  ton  of  concentrates.  Later,  143  tons  of  ore  from  the  east  drift 
of  the  same  shaft  were  milled,  realizing  500  dwts.  free  gold,  and  7  tons 
of  concentrates,  assaying  $602  per  ton.  The  percentage  of  sulphurets 
(iron  pyrites)  in  the  ore  varies  from  5  to  7  per  cent. 

There  are  over  2  acres  of  old  tailing  dumps,  8  feet  deep,  which 
material  assays  from  $7  to  $8  per  ton. 

Towards  the  end  of  1896,  the  mill  was  increased  to  40  stamps  with 
10  Frue  vanners,  and  a  5 -foot  Huntington  mill,  with  2  Triumph  con- 
centrators were  added.  The  milling  capacity  is  1J  tons  per  stamp  per 
day,  and  12  tons  per  day  in  the  Huntington  mill. 

Besides  the  above  equipment,  2  reverberatory  roasting  furnaces,  50x9 
feet  hearth,  and  a  chlorination  plant  with  two  2-ton  barrels,  filters,  etc., 
were  built. 

MINES    IN    MERIWEATHER    COUNTY. 

The  only  mine  of  importance  is  the  Wilkes,  situated  in  the  extreme 
northwest  corner  of  the  county.  It  is  stated  to  have  produced  $50,000 
from  1873  to  1878,  during  which  years  the  vein  (composed  of  quartz 
lenses  8  to  10  inches  thick)  was  mined  to  a  depth  of  130  feet.  The 
ore,  consisting  of  quartz,  with  about  3  feet  of  the  adjoining  wall-rock, 
mills  about  $4  per  ton. 

In  the  spring  of  1895  the  mine  was  opened  and  operations  conducted 
on  a  limited  scale  by  Mr.  John  Cross. 


L 


84  GOLD    MINING    IN    GEORGIA. 

MINES    IN    TOWNE    COUNTY. 

A  zone  of  ore-bearing  schists  about  3  miles  in  length  extends  across 
the  State  line  into  Clay  county,  "N.  C.  (see  p.  70). 

The  Warne  mine,  in  Clay  county,  E".  C,  is  situated  on  Brasstown 
creek,  about  8  miles  southwest  of  Haysville  and  not  more  than  \  mile 
north  of  the  Georgia  line. 

The  developments  consist  of  a  60-foot  shaft,  at  the  bottom  of  which 
the  quartz-vein  is  stated  to  be  2  feet  in  width.  There  are  no  under- 
ground workings  of  consequence.  The  property  is  equipped  with  a  10- 
stamp  mill  driven  by  a  turbine  wheel  with  a  20-foot  water-fall. 

The  Old  Field  mine,  in  Towne  county,  Ga.,  adjoins  the  Warne  on 
the  southwest.  Considerable  exploratory  work  has  been  done,  and  a 
number  of  quartz-veins  located.  There  appears  to  be  a  good  opportunity 
here  for  hydraulicking  the  saprolitic  material  over  a  considerable  area; 
with  a  ditch  line  2  miles  in  length  a  head  of  160  feet  can  be  attained. 

The  JSTancy  Brown  mine  adjoins  the  Old  Field  on  the  southwest,  be- 
yond which  lies  the  Hunt  mine  property,  where  the  main  developments 
consist  of  a  shaft  45  feet  deep,  and  a  tunnel  60  feet  long.  In  the 
former,  the  vein,  which  is  composed  of  vitreous  quartz,  is  stated  to  vary 
from  18  to  36  inches  in  width,  and  various  assays  have  shown  values 
ranging  from  $10  to  $17.  In  the  tunnel  the  quartz-vein,  which  strikes 
nearly  east  and  west  and  stands  vertically,  has  a  thickness  of  from  12  to 
15  inches,  which  has  given  reported  mill-test  values  of  $13.  The 
country  is  mica-gneiss  and  -schist,  striking  N.  70°  W.  These  rocks  are 
filled  with  quartz-stringers  or  veinlets,  and  in  general  the  district  is  not 
unlike  that  of  the  Dahlonega  region  in  Lumpkin  county. 

The  Jack  Brown  property  adjoins  the  Hunt  on  the  southwest.  The 
main  prospect  is  an  8-foot  quartz-vein,  which  has  a  promising  appearance 
and  is  stated  to  carry  values  from  $9  to  $125  per  ton.  The  strike  of 
the  vein  is  ~N.  75°  E.,  and  the  dip  is  nearly  vertical. 

The  Welborn  Hill  mine  is  situated  about  -J  mile  west  of  the  Jack 
Brown  on  a  parallel  zone  of  auriferous  schists.  It  was  last  worked  sev- 
eral years  ago  by  two  shafts  respectively  125  and  70  feet  deep,  cutting 
two  parallel  quartz-veins  respectively  36  and  30  inches  wide.  The 
strike  is  1ST.  40°  E.  and  the  dip  steeply  to  the  northwest.  The  property 
is  equipped  with  a  10-stamp  mill  of  the  Hall  type. 

THE    CAROLINA    BELT    (iN    GEORGIA). 

In  the  eastern  part  of  the  State  an  auriferous  district,  which  prob- 
ably represents  the  southwesterly  extension  of  the  Carolina  belt,  is 
developed  to  some  extent  in  McDuffie,  Warren,  Wilkes,  Lincoln,  and 
Columbia  counties. 


DISTRIBUTION  OF   GOLD   MINES   IN  THE    SOUTH  APPALACHIAN   REGION.     85 

The  most  prominent  mine  in  this  district  is  the  Smith  mine,  operated 
by  Mrs.  J.  Belknap  Smith.  It  is  situated  14  miles  northwest  of  Thom- 
son in  McDuffie  county. 

A  3-foot  vein  of  white  quartz,  carrying  free  gold,  pyrite,  chalcopyrite 
and  galena,  and  milling  from  $8  to  $24  by  simple  amalgamation,  has 
been  developed  by  two  shafts  to  a  depth  of  160  feet,  and  for  a  distance 
of  about  300  feet  along  the  strike  (nearly  north  and  south).  The  mill 
(10  stamps)  is  located  three  miles  from  the  mine  on  Little  river.  ±^o 
attempt  is  made  to  save  the  sulphurets,  and  the  tailings  are  stated  to 
carry  as  high  as  $12  per  ton. 

Other  mines  in  this  district  are  the  Columbia,  Egypt,  Tatham,  Wil- 
liams, Warren,  and  Magruder. 

GOLD   MINES   IN   ALABAMA.1 

MINES    IN    CLEBURNE    COUNTY. 

All  of  the  more  important  mines  of  the  county  are  located  in  the 
Arbacoochee  district,  situated  7  miles  southeast  of  Heflin,  the  nearest 
railroad  point.  In  the  earlier  days  extensive  placer  mining  was  earned 
on  about  §  of  a  mile  southwest  of  the  mining  village,  Arbacoochee, 
principally  in  the  Clear  Creek  valley.  The  auriferous  deposit  at  this 
point  covers  nearly  100  acres  in  Sections  5,  6  and  7,  T.  17,  R.  11  E. 

During  the  summer  of  1895  a  pocket  of  very  rich  quartz  was  opened 
up  in  one  of  the  old  placer  pits  on  the  boundary  line  between  Sections 
6  and  7.  It  is  stated  that  between  $1000  and  $2000  of  coarse  gold 
was  taken  from  about  400  pounds  of  ore  and  the  immediately  overlying 
gravel.  This  find  created  considerable  local  stir,  and  prospecting  was 
being  pushed  along  the  strike  of  the  quartz-vein  as  far  as  the  direction 
could  be  determined  from  the  very  limited  dimensions  of  the  ore  lens, 
the  latter  having  a  maximum  width  of  8  inches,  a  dip  of  about  30  , 
and  pinching  rapidly  along  the  strike  in  a  distance  of  about  6  feet. 
The  ultimate  value  of  this  find  will  depend  on  the  continuation  of  this 
shoot  in  length  and  depth,  or  the  discovery  of  new  ore-bodies  along  the 
strike  of  the  veins.  Prospecting  along  this  ore-lead  was  still  in  progress 
during  1896. 

The  only  hydraulic  work  in  the  State  was  carried  on  for  a  short  time 
by  the  Arbacoochee  Hydraulic  Company  on  side-hill  deposits,  about 
-J  mile  east  of  Arbacoochee.  The  limited  supply  of  water  and  poor 
management  are  given  as  the  reasons  for  failure. 

The  Anna  Howe,  the  Anna  Howe  Extension,  the  Crutchfield  and  the 
Valdor   are   adjoining  properties   in   the   Arbacoochee   district.     These 

1  For  a  more  complete  statement  concerning-  gold  mines  and  mining  in  Alabama  see  Bulletins 
3  and  5  of  Alabama  Geological  Survey,  referred  to  on  p.  13. 


86  GOLD    MINING    IN    ALABAMA. 

mines  are  located  on  a  series  of  narrow,  irregular,  lenticular  quartz- 
veins  having  quite  a  flat  clip.  The  Anna  Howe  was  developed  to  a 
depth  of  about  100  feet  when  the  vein  pinched  out  and  the  mine  was 
abandoned.  The  equipment  consists  of  a  Huntington  mill  and  Frue 
vanner. 

The  Chulafinnee  district  is  about  8  miles  west  of  Arbacoochee,  in 
Sections  14,  15,  16,  22,  23,  24,  25,  T.  17,  E.  9  E.  As  at  Arbacoochee, 
extensive  placer  mining  has  been  prosecuted  here  in  the  past,  but  has 
long  since  been  abandoned.  Recent  prospecting  has  disclosed  some 
rich  quartz-stringers  on  the  property  of  Mr.  Burrell  Higginbotham.  The 
old  King  mine,  at  which  a  stamp  mill  was  in  operation  over  20  years 
ago,  is  in  the  same  vicinity. 

The  Turkey  Heaven  District  comprises  a  series  of  mines  situated 
along  the  base  of  the  Turkey  Heaven  mountains.  Among  the  more 
important  properties  are  the  Miller,  the  Crown  Point,  the  Moss-Back. 
the  Pritchard,  the  Lucky  Joe,  the  Hicks-Wise,  the  Lee,  the  Crumpton, 
the  Middlebrook,  the  Sutherland,  the  Bennifield,  the  Marion- White,  and 
the  James  Moore. 

The  Crown  Point  mine  is  equipped  with  a  5-stamp  mill.  The  Moss- 
Back  is  one  of  the  early  discoveries;  it  is  equipped  with  a  10-stamp  mill. 
The  Lucky  Joe  1  is  the  most  extensively  developed  mine  in  the  district. 
It  was  opened  in  1593,  and  a  stamp-mill  (Fraser  and  Chalmers  make) 
erected.  It  is  stated  that  the  mill  runs  saved  $2.27  a  ton  by  amalgama- 
tion, the  cost  of  mining  and  milling  being  $1.35  to  $1.45  per  ton.  The 
capacity  of  the  mill,  using  30-mesh  screens,  was  30  tons  per  day.  The 
pay-ore  lies  in  chimneys  and  shoots  from  3  to  4  feet  thick,  dipping 
about  30°  eastward.  The  workings  consist  of  about  300  feet  of  drifting 
and  cross-cutting.  Apparently  the  development  of  ore  did  not  prove 
satisfactory,  as  the  mine  was  abandoned  during  the  summer  of  1894. 

The  Moss-Back  mine,  near  the  Lucky  Joe,  was  opened  in  the  early 
seventies.     A  10-stamp  mill  was  erected  in  1890. 

The  Hicks-Wise  mine  was  developed  by  a  vertical  shaft  110  feet 
deep  with  levels  at  20,  40,  and  85  feet.  Of  3000  tons  of  ore  milled 
it  is  stated  that  a  yield  of  $2  per  ton  was  obtained  by  amalgamation. 
The  ores  are  graphitic. 

The  Lee  mine  is  developed  by  an  inclined  shaft  sunk  to  a  depth  of 
40  feet  on  the  dip  of  the  ore-body  (45°),  on  which  level  a  drift  of  121 
feet  in  length  has  been  run  in  ore,  which  varies  from  2  to  5  feet  in  thick- 
ness. The  plant  in  operation  in  1894  consisted  of  3  arrastras  and  a 
Blake  crusher.     It  is  stated  that  the  ore  will  mill  $5  per  ton. 

The  Middlebrook  is  opened  by  an  inclined  shaft  20  feet  deep  on  an 
ore-body  5  feet  in  thickness.     Panning  tests  have  shown  $5  per  ton. 

1  For  full  description  of  this  property   ee  Engineering  and  Mining  Journal,  vol.  lvi,  1S93,  p.  79. 
by  W.  M.  Brewer. 


- 


DISTRIBUTION  OF  GOLD   MINES   IN  THE   SOUTH  APPALACHIAN   REGION.     87 

The  Sutherland  ore-body  closely  resembles  the  Middlebrook.  It 
has  been  but  slightly  developed  to  a  depth  of  about  30  feet.  An  old- 
fashioned  wooden  stamp  mill  with  iron  shoes  stands  on  the  property. 

The  Kemp  Mountain  district  is  situated  in  T.  17,  K.  10  E.  and  T. 
17,  R.  11  E.  The  two  most  important  properties  are  the  Eckels  and 
the  Golden  Eagle.  The  Eckels  mine  was  opened  in  1893  by  an  open- 
cut  8  feet  deep  and  50  feet  long,  exposing  ore,  thin  seams  of  quartz 
in  decomposed  graphitic  schist,  the  entire  distance.  A  shaft  was  sunk 
from  the  floor  of  the  open  cut  to  a  depth  of  65  feet.  The  dip  is  vertical 
down  to  36  feet,  when  it  changes  to  60°  south.  A  cross-cut  at  the  bot- 
tom of  the  shaft  showed  that  the  ore-body  had  narrowed  down  to  18 
feet.  In  1891-  the  shaft  was  deepened  to  100  feet  and  the  same  condi- 
tions found  to  hold.  No  sytematic  work  of  treating  the  ore  has  been 
done. 

The  Golden  Eagle  (formerly  known  as  the  Price)  mine  has  been 
opened  by  a  shaft  75  feet  deep  on  the  dip  of  the  ore-body  about  50° 
southeast.  The  vein-matter,  quartz-stringers  in  hydromica-schist,  is 
10  feet  thick  at  the  bottom  of  the  shaft  and  is  highly  sulphuretted,  con- 
taining also  arsenical  pyrites.      Some  rich  ore  has  been  found  here. 

The  Dyne-Creek  Company  has  recently  made  a  number  of  openings 
in  the  vicinity  of  Kemp  Mountain  and  south  of  Arbaeoochee. 

MINES  IN  RANDOLPH  COUNTY. 

The  only  mine  of  prominence  is  the  Pinetucky.  It  might  be  classed 
as  belonging  to  the  Arbaeoochee  district,  and  is  located  about  2  miles 
south  of  Micaville  and  11  miles  from  Heflin,  near  the  northern  boun- 
dary of  the  county. 

The  occurrence  of  gold-bearing  quartz  here  was  discovered  by  a 
Mr.  Knight  in  the  early  days  of  gold  digging.  Numerous  shallow 
workings,  perhaps  the  most  extensive  at  any  one  point  in  the  South, 
extend  in  a  continuous  line  for  over  a  mile  along  the  outcrop  of  the 
vein,  and  give  evidence  of  the  large  amount  of  work  done  here  in  time 
past,  as  well  as  of  the  continuity  of  the  vein.  These  old  workings  have 
been  carried  to  a  maximum  depth  of  70  feet,  and  a  large  amount  of 
drifting  has  been  done  on  the  course  of  the  vein,  which  is  nearly  north 
and  south,  the  dip  being  about  20°  east.  The  vein  is  a  fissure  of  hard, 
bluish  quartz  in  walls  of  garnetiferous  hornblende-schist.  It  varies  in 
thickness  from  the  fraction  of  an  inch  to  12  inches.  The  values  are 
concentrated  in  chimneys  or  shoots,  and  vary  from  a  trace  to  $150  a 
ton.  It  is  claimed  that  the  ore  will  carry  an  average  of  $10  per  ton. 
About  one-half  of  the  gold  is  free-milling,  the  other  half  being  con- 
tained in  the  sulphurets   (pyrites).     The   percentage   of  pyrite  in   the 


S8  GOLD    MINING    IN    ALABAMA. 

ore  is  less  than  1  per  cent.  Assays  of  concentrates  have  shown  from 
$90  to  over  $600  per  ton. 

A  few  years  ago  a  complete  and  well-constructed  10-stamp  mill  of 
Western  pattern  (Fraser  and  Chalmers)  was  erected  on  the  property 
abont  700  feet  east  of  the  outcrop.  A  vertical  shaft  was  started  in  the 
mill  house  with  the  object  of  cutting  the  vein  in  depth  and  hoisting  the 
ore  direct  to  the  grizzly  and  crusher,  situated  at  the  top  of  the  building. 
This  shaft  was  sunk  to  a  depth  of  50  feet  and  then  abandoned  for  lack 
of  funds.  In  the  spring  of  1895  the  property  was  leased  to  the  Fair 
Mining  and  Milling  Company  of  Chicago,  which  began  operations  by 
sinking  three  (3)  vertical  diamond  drill-holes.  The  first  of  these  was 
driven  to  a  depth  of  205  feet  without  cutting  ore.  The  cores  showed 
granite  at  a  depth  of  55  feet,  which  alternated  with  the  garnetiferous 
country  schists  to  the  bottom  of  the  hole.  The  second  hole,  bored 
about  150  feet  east  of  the  old  workings  to  a  depth  of  130  feet,  also 
failed  to  reach  the  vein.  The  country  schists  were  passed  through  at 
60  feet,  below  which  they  alternated  with  granite.  The  third  hole, 
only  80  feet  east  of  the  old  workings,  was  drilled  to  a  depth  of  70  feet. 
After  passing  through  the  country  schists,  granite  was  encountered  at  a 
depth  of  47  feet,  immediately  below  which  the  quartz-vein  was  found 
12  inches  in  thickness;  below  that  a  layer  of  soft  gouge,  and  below  that 
garnet-schist  and  granite.     A  working  shaft  was  started  at  this  point. 

In  gold  quartz-veins  of  this  size  the  result  obtained  by  diamond  drill 
borings  might  often  be  misleading,  as  the  gold-bearing  vein  can  at  times 
be  distinguished  from  other  quartz  only  by  its  gold  contents;  about  this 
the  drill-core,  and  still  more  the  cuttings  used  as  assay  samples,  can  give 
no  reliable  information.  However,  such  explorations  may  disclose  other 
facts  of  interest,  as,  for  instance,  in  this  case  the  discovery  of  granite 
overlying  the  vein  in  depth,  which  may  give  a  clue  to  the  formation  of 
the  vein  and  more  intelligently  direct  search  for  it. 

The  prospecting  work  at  this  mine  was  done  with  a  small  Sullivan 
drill  (J-ineh  core).  The  drill  runner  furnished  by  the  Sullivan  Diamond 
Drill  Company,  of  Chicago,  received  $90  per  month.  The  cost  of  under- 
ground labor  in  this  district  is  $1  per  day  and  for  top  labor  80  cents  to 
$1;  cord  wood,  75  cents  per  cord;  freight  to  HefTin  (by  wagon),  14  miles, 
20  cents  per  100  pounds. 

Near  the  center  of  this  county,  at  Wedowee,  some  placers  have  been 
operated. 

The  Goldberg  district  lies  in  the  extreme  western  part  of  the  county, 
running  partially  into  Clay  county  near  Abner.  Attention  has  been 
paid  in  this  direction  almost  entirely  to  placer  mining  along  the  bottom 
of  Crooked  creek.  A  very  considerable  amount  of  prospecting  has  also 
been  done  on  the  vein  formations,  but  no  regularly  producing  mines 


I   Tn» 


DISTRIBUTION  OF   GOLD   MINES   IN  THE  SOUTH  APPALACHIAN   REGION.     89 

have  yet  been  developed.     Arsenical  pyrite  is  of  common  occurrence 
in  the  district. 

MINES    IN    CLAY    COUNTY. 

The  more  important  mining  operations  have  been  carried  on  in  the 
Idaho  district,  which  embraces  an  area  of  about  3  miles  square.  The 
country-rocks  are  graphitic  mica-  and  hornblende-schists,  often  garnet- 
iferous.  The  principal  properties  are  the  Idaho,  ITobbs,  Laurel,  Chin- 
capina,  California,  and  Horns  Peak. 

The  Idaho  (or  Franklin)  mine  is  situated  in  Sec.  3,  T.  20,  K.  7  E., 
on  the  northwestern  side  of  Shinbone  ridge.  The  main  ore-body  con- 
sists of  a  large  mass  of  the  country  schists  interlaminated  with  quartz- 
seams  and  largely  stained  with  manganese  oxide.  The  schistosity  stands 
almost  vertical.  This  ore-body,  which,  has  a  thickness  of  50  feet,  is 
opened  by  cuts  Avhich  extend  for  over  300  feet  along  the  line  of  strike 
and  to  a  maximum  depth  of  60  feet. 

The  second  ore-body  is  about  150  feet  northwest  of  the  above.  It  is 
locally  called  the  "  Little  Sampson  vein."  But  little  work  has  been  done 
here. 

The  Idaho  ore  is  stated  to  carry  $2  per  ton  in  free  gold.  The  milling 
plant,  which,  was  in  operation  in  the  winter  of  1896,  consists  of  a  5-stamp 
mill  (crushing  capacity  10  tons  in  24  hours),  and  a  5-foot  Huntington 
mill  (crushing  capacity  20  tons  in  24  hours),  the  former  crushing 
through  round  punched  2  mm.  screens,  and  the  latter  through  1  mm. 
slotted  screens.  The  pulp  from  both  mills  goes  over  shaking  coppers 
and  thence  over  stationary  coppers,  which  are  barred  with  riffles.  From 
here  it  flows  over  blanket  sluices  8  feet  wide  at  the  Huntington  and  4 
feet  wide  at  the  stamp-mill.  The  cost  of  mining  and  milling  is  stated 
to  be  50  cents  per  ton,  and  the  cost  of  delivering  from  mine  to  mill  15 
cents  per  ton. 

The  following  rates  of  wages  are  paid:  Miners,  75  cents  per  day  (10 
hours);  foremen,  millmen,  and  engineers,  $1  per  day;  millwright,  $1.25 
per  day.     The  cost  of  fuel  is  $2  per  day. 

The  Laurel  mine  is  supposed  to  be  an  extension  of  the  Little  Sampson 
ore-body,  and  the  character  of  the  ores  is  very  similar. 

The  Chincapina  mine  is  situated  on  a  ridge  to  the  north  of  the 
Laurel  and  Idaho  mines.  The  character  of  the  ore-body  is  similar  to 
that  of  the  Idaho,  though  the  dip  is  more  inclined,  about  30°  southeast. 
"No  work  of  consequence  has  been  done. 

At  the  California  mine  a  10-stamp  mill  was  erected  and  operated  sev- 
eral years  ago. 

The  Horns  Peak  mine  is  situated  about  1  mile  west  of  the  Idaho. 
The   ore-body,   which   resembles  the   others   in   this   district,   has   been 


90  GOLD    MINING    IN    TENNESSEE. 

opened  by  a  cross-cut  tunnel,  determining  its  thickness  to  be  about  30 
feet.  Tests  made  in  a  small  5-stamp  mill  located  in  the  vicinity  have 
demonstrated  a  saving  of  $2  per  ton  by  amalgamation. 

MINES  IN  TALLADEGA  COUNTY. 

The  occurrence  of  gold  in  this  county  is  limited  to  the  extreme  eastern 
portion,  in  the  Blue  Ridge  mountain  range.  The  Riddle  and  Story 
mines  have  been  worked  to  some  extent. 

The  ore-body  at  the  Riddle  mine  is  a  highly  sulphuretted  quartz- 
vein,  having  a  very  flat  dip  towards  the  southeast.  It  has  been  opened 
by  an  inclined  shaft  on  the  dip  to  a  depth  of  100  feet.  The  thickness 
of  the  quartz  lenses  is  about  4  inches,  pinching  to  a  mere  seam  in  places. 
Assays  have  shown  values  varying  from  $20  to  $150  per  ton.  The 
prospect  pits  extend  for  over  half  a  mile  on  the  course  of  the  vein. 

The  Story  mine  lies  in  the  adjoining  section  to  the  Riddle.  The  ore 
was  mined  some  years  ago  from  an  incline  on  the  vein  to  a  depth  of  60 
feet.     It  is  similar  to  that  of  the  Riddle  mine. 

The  occurrence  of  gold  in  Coosa,  Chilton,  Chambers  and  Tallapoosa 
counties  has  been  fully  described  by  Dr.  W.  B.  Phillips  in  Bulletin 
No.  3,  Geological  Survey  of  Alabama. 

The  latter  county  was  at  one  time  the  seat  of  extensive  mining  opera- 
tions in  the  Goldville,  Hog  Mountain,1  Silver  Hill,  Gregory  Hill,  Blue 
Hill,  and  Farrow  Mountain  districts.2 

GOLD   MINES   IN   TENNESSEE. 

The  gold  produced  in  this  State  has  been  obtained  entirely  from  petty 
placer  workings  in  Monroe,  Polk,  McMinn,  and  Blount  counties.  The 
most  prolific  sources  have  been  the  deposits  along  Coco  creek,  a  trib- 
utary of  the  Hiawassee  river  in  Monroe  county.  Other  gold-bearing 
streams  in  this  county  are  the  Citico  and  Cane  creeks,  and  the  head- 
waters of  the  Tellico  river.  Along  Whippoorwill  branch,  a  tributary, 
of  the  Tellico,  small  gold  quartz-veins  have  been  discovered,  but  they 
have  never  been  worked. 

In  the  latter  part  of  1896  a  company  known  as  the  Cooper  Gold 
Mining  Company  was  organized  for  the  purpose  of  developing  the  Coco 
creek  gold  fields.3 

1  Extensive  prospecting-  work  has  recently  been  done  at  Hog  Mountain  with  the  result  of 
showing  the  existence  thereof  a  number  of  thick  veins  of  low  grade  ore,  averaging  perhaps 
$4  or  $5  a  ton. 

So  also  in  the  vicinity  of  the  old  Ulrich  mines,  and  across  the  river  at  the  Bonner,  Terrell, 
and  Gunn  mines,  much  work  has  been  done  within  the  past  twelve  months. 

2  See  Bulls.  Nos.  3  and  5,  Geoloq.  Survey  of  Alabama. 
3Eng.  and  Min.  Jour.,  vol.  lxii,  p.  374. 


■j^tftt 


CHAPTER  V 

THE  MINING  AND  MILLING  PRACTICE  AT  SOME  OF  THE 
CHARACTERISTIC  PLACER  AND  FREE-MILLING 

MINES. 

THE   CRAWFORD   (OR  INGRAM)   MINE,   STANLY  COUNTY,   N.    C. 

This  mine  is  situated  4  miles  southeast  of  Albemarle,  in  the  Carolina 
belt.  It  represents  a  type  of  working  in  virgin  placer  ground,  the  gold 
being  coarse,  usually  in  nuggets.  The  mining  tract  (180  acres)  com- 
prises a  flat  hollow  or  depression,  averaging  250  feet  in  width,  which 
is  drained  by  a  small  branch.  The  country-rock  is  the  dark  greenish 
Monroe  slate  (sedimentary),  lying  in  a  flat  synclinal  trough.  The  aurif- 
erous grit,  lying  on  the  slate  floor,  is  composed  of  angular  fragments  of 
quartz  and  country-rock  bound  in  a  clay  matrix;  the  cement  is  often 
hard  and  stained  a  brownish  or  black  color.  The  quartz  is  of  a  milky, 
vitreous  variety,  seldom  showing  ferruginous  stains;  some  pieces  show 
parallel  walls  (vein  structure)  from  a  few  inches  up  to  1  foot  in  thick- 
ness. No  free  gold  has  been  found  in  this  quartz.  The  thickness  of 
the  grit  in  the  center  of  the  synclinal  basin  is  from  1^  to  2  feet,  and 
of  the  over-lay  2  to  4  feet,  thinning  out  towards  the  edges.  The  length 
of  the  deposit  on  the  company's  property  is  about  a  quarter  of  a  mile. 
The  adjoining  property  on  the  north  is  owned  by  Mr.  F.  A.  Fesperman, 
whose  place  has  been  worked  by  tributors.  The  gold  found  at  the 
Crawford  is  altogether  coarse,  from  the  size  of  a  pin's  head  to  nuggets 
of  considerable  weight.  The  largest  nugget  was  found  on  August  22, 
1895,  and  weighed  10  pounds.  The  so-called  De  Berry  nugget,  found 
April  8,  1895,  weighed  8  pounds  5  ounces.  These  nuggets  are  scarcely 
at  all  water-worn,  being  rough  and  irregular  in  shape.  The  fineness  of 
the  gold  varies  from  850  to  900. 

On  the  hillside  to  the  west  of  the  placer  mine  several  quartz-veins 
have  been  explored  by  shallow  openings  along  the  outcrop.  One  of 
these  is  from  2  to  3  feet  thick,  and  dips  steeply  to  the  east,  cutting  the 
slates  both  in  strike  and  dip.  The  quartz,  so  far  as  explored,  has  been 
found  generally  barren,  though  in  several  places  gold  has  been  panned 
from  the  crushed  rock;  but  no  larger  pieces  have  been  found  giving  any 
possible  clue  as  to  the  origin  of  the  nuggets  of  the  placer  deposits. 

Gold  was  first  discovered  in  this  bottom  in  August,  1892,  the  prop- 


E 


92 


GOLD    MINING    IN    NORTH    CAROLINA. 


-    - 


£W 


THE    MINING   PRACTICE CEAWFORD    MINE.  93 

erty  being  at  that  time  a  portion  of  the  W.  S.  Ingram  farm.  For  two 
years  it  was  worked  spasmodically  by  tributors,  and  16  to  17  pounds  of 
nuggets  were  obtained.  In  1894  the  property  was  bought  by  the  Craw- 
ford Mining  Company  of  New  York,  and  was  put  under  the  able  man- 
agement of  Mr.  Richard  Eames,  Jr.,  of  Salisbury,  !N\  C.  A  sketch  of 
the  method  of  working  which  was  being  pursued  in  1895  is  given  in 
fig.  6. 

The  bottom  having  insufficient  grade  to  carry  off  the  tailings  with 
the  limited  amount  of  water  at  hand,  a  washing  tank  and  sluice  were 
put  up  on  the  side  hill  at  an  elevation  of  about  30  feet  above  the  creek. 
The  deposit  was  mined  by  a  system  of  parallel  trenches  12  feet  wide, 
worked  from  the  lower  end  of  the  deposit  upward.  Track  was  laid  in 
these  as  they  advanced.  The  upper  6  to  18  inches  of  the  over-lay  were 
thrown  off,  the  remaining  1-J  to  2  feet,  together  with  the  true  grit 
(gravel)  and  6  to  12  inches  of  the  bed-rock,  were  shovelled  into  cars 
holding  about  half  a  cubic  yard.  These  were  trammed  to  the  foot  of 
the  inclined  plane  (8),  and  hoisted  to  the  top  of  the  washing  plant  by  a 
small  friction-drum  engine  (3)  (see  fig.  6).  This  tank  was  built  of 
plank  and  is  about  50  feet  long,  18  feet  wide  and  6  feet  high.  On  one 
of  the  sides  there  is  a  door  or  opening  4  feet  wide,  reaching  to  within  4 
inches  of  the  bottom  to  a  sill.  The  grit  was  dumped  into  the  tank  and 
a  constant  stream  of  water  kept  flowing  over  it.  The  action  of  this 
stream  was  reinforced  by  water  played  on  the  material  from  a  hose  nozzle 
under  a  head  of  30  feet.  This  head  was  obtained  from  a  stand-pipe  (4) 
to  which  water  was  pumped  from  a  reservoir  (1)  by  means  of  a  Hall 
duplex  pump  (2)  with  a  4-inch  discharge.  Excepting  at  the  time  of  the 
clean-up,  the  tank  was  kept  nearly  full  of  gravel,  and  under  the  com- 
bined action  of  the  two  streams  of  water,  closely  imitating  natural 
agencies,  a  very  good  concentration  of  the  coarser  nuggets  was  attained 
in  the  tank.  The  material,  partly  assisted  with  a  rake,  flowed  over  a 
grizzly  (6),  the  bars  of  which  were  set  1-J  inches  apart.  The  coarser  peb- 
bles and  boulders  were  forked  off,  while  the  finer  gravel  and  sand  were 
carried  down  into  a  sluice  (7)  situated  below  the  grizzly.  The  sluice 
was  400  feet  long,  12  inches  wide  and  10  inches  deep,  and  had  an  in- 
clination of  6  inches  in  10  feet.  It  contained  only  about  20  feet  of 
riffles,  and  these  were  situated  about  100  feet  below  the  grizzly.  Orig- 
inally, the  whole  sluice  was  filled  with  riffles,  but  these  were  removed 
when  it  was  recognized  that  they  were  superfluous  for  saving  gold. 
The  first  hundred  feet  of  the  sluice  were  found  to  aid  in  thoroughly 
washing  and  disintegrating  the  material  before  it  reached  the  riffles,  and 
gold  was  seldom  found  below  the  first  four  or  five  feet  of  the  rirrles. 
The  upper  riffles  consisted  of  diagonal  slots  cut  in  2-inch  plank,  which 
was  laid  in  the  bottom  of  the  sluice.  The  lower  riffles  were  of  the  longi- 
tudinal variety  (see  fig.  8). 


94 


GOLD    MIKING    IN    NORTH    CAROLINA. 


The  upper  riffles,  as  well  as  the  surface  of  the  material  in  the  tank, 
were  examined  every  evening  for  larger  nuggets.  A  complete  clean-up 
was  made  at  odd  intervals,  depending  upon  the  richness  of  the  material 
worked  on,  etc.  The  gravel  in  the  tank  was  entirely  worked  down  by 
means  of  the  hose,  the  coarser  nuggets  picked  out  by  hand,  and  the 
heavy  sand,  together  with  similar  material  found  in  the  bottom  of  the 
sluice,  after  taking  up  the  riffles,  was  washed  in  a  rocker.  Xo  quick- 
silver was  used,  there  being  no  fine  gold  whatever.  A  loss  of  gold 
would  more  likely  be  in  the  form  of  larger  nuggets,  which  might  be 
overlooked  in  forking  out  the  coarser  material,  or  which,  on  account 
of  their  round  form  and  size,  might  roll  over  the  riffles  to  the  tailing 
heap.  One  large  nugget,  of  the  shape  and  size  of  a  hen's  egg,  was 
found  on  the  latter.  Clay  balls  (sluice-robbers)  also  cause  considerable 
loss. 


Fig.  7. — Rocker  used  by  tributors  ;   Crawford  Mine. 


pgggg  |  V/7Z7/7/7/7/7A 

Upper  End.  Lower  End. 

Fig.  8. — Riffles  in  sluice-box;   Crawford  Mine.     Scale,  }{  ineh  =  l  foot. 

When  working  to  full  capacity,  25  men  were  employed  at  these 
mines — 5  men  at  the  tank  and  sluice,  1  playing  the  hose  and  dumping 
cars,  1  raking  gravel  out  of  the  tank,  and  3  helping  the  material  down 
the  sluice  and  over  the  riffles,  forking  out  the  coarser  pebbles.  The 
latter  force  was  necessitated  by  the  limited  supply  of  water  and  the  de- 
sire to  work  as  large  quantities  as  possible.  Their  work  might  perhaps 
have  been  assisted  by  the  use  of  a  much  shorter  sluice,  and  a  somewhat 
steeper  inclination  of  the  same,  without  endangering  loss  in  gold  of  such 
a  coarse  character.  The  remainder  of  the  force,  excepting  foreman  and 
engineer,  were  employed  in  digging  gravel,  taking  up  bed-rock,  etc. 
An  average  day's  output  consisted  of  80  carloads,  about  45  cubic  yards 
of  loose  gravel.  Two  and  one-half  to  three  cords  of  wood  were  burnt  a 
day,  at  65  cents  per  cord.  Labor  was  paid  at  the  rate  of  60  to  65  cents 
per  day.  These  figures,  with  reasonable  additions  for  superintendence, 
supplies,  etc.,  placed  the  cost  of  mining  gravel  by  this  method  at  about 
50  cents  per  loose  cubic  yard.  From  June  until  November,  when  the 
water-supply  is  very  limited,  the  right  of  mining  the  gravel  was  let  out 
to  tributors,  who  turned  in  as  royalty  J  of  the  finer  gold,  including 


-■ 


THE    MINING    PRACTICE BURKE    COUNTY.  95 

pieces  up  to  1  ounce  in  weight,  and  -J  of  the  larger  nuggets  (above  1 
ounce).  The  tributes  worked  in  pairs,  one  pitting  and  taking  out  the 
bed-rock  while  the  other  one  manipulated  the  rocker  (cradle),  shown  in 
fig.  7.  It  is  made  up  like  a  barrel,  with  half-inch  staves,  smoothed  on 
the  inside,  with  solid  heads,  the  latter  being  a  little  more  than  half  a 
circle.  One  wheelbarrow-load  is  put  in  the  rocker  at  a  time.  After  the 
gravel  is  thoroughly  disintegrated  by  vigorous  motion  of  the  rocker, 
the  pebbles,  etc.,  are  thrown  out,  and  finally,  by  a  light  movement,  the 
finer  and  heavier  portions  are  examined  closely  by  eye.  It  is  practically 
a  panning  process  on  a  larger  scale.  Fifteen  minutes  are  occupied  in 
cleaning  up  one  charge. 

THE  MILLS  PROPERTY,  BURKE  COUNTY,  N.  C. 

This  property  is  situated  near  Brindletown,  about  14  miles  southwest 
from  Morganton.  It  comprises  an  area  of  2460  acres,  including  the 
eastern  portion  of  Pilot  Knob  and  the  western  flanks  of  the  South  moun- 
tains, being  drained  by  the  waters  of  Silver  creek.  The  problem  here 
presented  is  the  reworking  of  old  gravel  deposits  by  a  simple  hydraulick- 
ing  process  where  the  grade  is  sufficient,  or,  where  this  is  not  the  case, 
by  raising  the  material  to  the  surface  by  hydraulic  elevators. 

Geologically,  the  locality  is  in  the  South  mountain  belt.  The  general 
strike  of  the  crystalline  schists  'is  1ST.  20°  W.  and  the  dip  20°  1ST.E.  The 
rocks  are  decomposed  to  a  considerable  depth,  reaching  often  50  feet  and 
at  times  100  feet.  The  strike  of  the  auriferous  quartz-veins  is  ~N.  60° 
to  70°  E.  and  the  dip  70°  to  80°  KW.  These  veins  are  usually  from  a 
knife  edge  to  several  inches  in  thickness,  and  are  too  small  to  work  indi- 
vidually. One  vein  from  12  to  18  inches  in  thickness  has  been  ex- 
plored, but  was  found  to  be  almost  barren.  The  gravel  deposits  occupy 
the  present  stream  beds  and  adjoining  bottoms,  and  the  ancient  channels 
now  covered  with  deep  over-burden  and  extending  into  the  hillsides 
which  flank  the  mountain.  From  Pilot  Knob  and  along  its  lower  slopes, 
a  number  of  these  deep  channels  radiate  in  all  directions. 

The  facilities  for  obtaining  water  for  mining  purposes  are  good, 
though  beset  with  difficulties.  The  numerous  streams  which  have  their 
rise  in  the  South  mountains  are  small  though  of  good  flow  throughout 
most  seasons,  and  it  is  practicable  to  collect  their  water  and  lead  it  to 
the  larger  part  of  the  mining  ground  in  ditch  and  flume-lines  and  reser- 
voirs with  sufficient  head  for  sluicing  and  hydraulicking  purposes. 
However,  the  summer  months  cannot  be  depended  upon  for  steady  work, 
as  the  water-supply  is  apt  to  be  cut  short  by  droughts.  The  chief  im- 
pediment is  in  the  loss  of  grade  before  the  mining  ground  in  the  lower 
country  is  reached,  owing  to  the  deep  and  numerous  indentations  of  the 
mountains   which   it  is   necessary  to   circumvent.     It  is   impossible    to 


96 


GOLD    MINING    IN    NORTH    CAROLINA. 


•  M 


THE    MINING    PRACTICE BURKE    COUNTY.  97 

water  some  portions  of  the  sidehills  except  by  pumping  into  reser- 
voirs or  by  constructing  expensive  syphon-lines. 

Brindle  creek  on  the  Mills  property  was  the  site  of  the  first  discovery 
of  gold  in  this  part  of  North  Carolina,  in  1828.  "With  few  exceptions, 
most  of  the  virgin  placer  ground  above  alluded  to  has,  by  more  or  less 
continuous  mining  operations  since  then,  been  worked  as  high  as  water 
could  be  obtained  with  the  present  ditch  lines.  Much  of  the  gravel 
has  been  washed  over  as  many  as  three  times.  As  no  regular  records 
have  ever  been  kept,  it  is  impossible  to  speak  intelligently  of  the  value 
of  these  gravel  deposits.  Small  channels  yielding  as  high  as  $20  per 
cubic  yard  have  been  worked,  but  in  general  the  gravel  will  yield 
from  4  to  50  cents.  At  present,  the  available  mining  ground  may 
be  divided  into  two  general  classes:  first,  the  bottom  and  ancient  channel 
gravel  deposits;  second,  the  decomposed  country-rock  in  place,  contain- 
ing belts  of  small  auriferous  quartz-veins.  Not  much  attention  has 
been  paid  to  the  latter,  excepting  by  tributors  who  in  a  spasmodic  way 
have  worked  some  deposits  on  the  flanks  of  Brindle  ridge,  gouging  out 
the  small  rich  quartz-veins,  and  extracting  the  gold  by  crushing  in  hand- 
mortars  and  panning;  they  pay  a  royalty  of  16f  per  cent,  to  the  owner. 
Captain  J.  C.  Mills  at  one  time  successfully  worked  one  of  these  small 
quartz-belts  by  sluicing  to  a  small  stamp-mill  (Dahlonega  method),  but 
the  mill  was  destroyed  by  fire  and  never  rebuilt. 

In  1894  an  English  company  was  formed  with  the  object  of  again 
reworking  the  principal  gravel  deposits  and  obtaining  as  a  by-product 
the  monazite,  which  occurs  concentrated  with  the  gold  and  is  derived 
from  the  adjacent  country-rocks  by  disintegration.  Over  a  year  was 
spent  in  preparing  the  mining  ground,  building  and  repairing  ditches, 
flumes,  etc.  It  was  proposed  to  concentrate  the  work  at  two  points,  the 
first  in  the  bottom  land  of  Silver  creek,  using  a  giant  and  hydraulic 
elevator;  the  second  in  the  bed  of  Magazine  or  Parker  branch,  using  a 
giant  and  continuous  sluice-box  system. 

PLACER    DEPOSITS    ON    SILVER    CREEK. 

Silver  creek  forms  one  of  the  main  drainages  of  the  South  mountains. 
The  placer  deposits  which  it  was  proposed  to  rework  on  the  Mills  prop- 
erty are  situated  near  its  headwaters.  They  are  about  1  mile  in  length 
and  are  located  mainly  upon  the  west  bank,  on  which  the  gravel  often  ex- 
tends out  a  distance  of  500  to  600  yards.  The  main  difficulty  encoun- 
tered was  the  want  of  fall  in  the  bed,  a  feature  common  to  many  South- 
ern placers.  It  amounts  in  this  case  to  less  than  1  foot  in  100.  To  over- 
come this  obstacle  for  hydraulicking  with  continuous  sluice,  the  use  of 
the    hydraulic    gravel    elevator   was    decided    upon.     Fig.    9    gives    a 


98 


GOLD    MINING    IN    NORTH    CAROLINA. 


rough  sketch  of  the  plant  and  method  proposed.  Twelve  miles  of  ditch 
and  flume  line  (1)  carry  the  water  from  a  reservoir,  through  the  Dan 
Sisk  gap  in  the  South  mountains,  to  a  penstock  (4),  situated  200  feet 
above  the  level  of  the  creek  bed.  The  ditch  is  cut  about  8  inches  deep 
by  20  inches  wide,  at  a  cost  of  about  25  cents  per  rod,  and  is  given  a 
grade  of  from  \\  to  3  inches  in  100  feet.  The  flumes  are,  at  ordinary 
grade,  18  inches  wide  by  12  inches  deep  (see  fig.  10). 

A  sill,  bent,  top  and  side  brace  are  erected  every  6  feet  at  the  jointing 
point  and  middle  of  each  box.  The  bents  are  made  of  rough  lagging 
seldom  more  than  6  inches  in  diameter,  the  greatest  height  of  trestle 
being  less  than  30  feet.  The  sill  of  the  flume  acts  as  a  cap  for  the 
posts.  Wherever  a  small  grade  becomes  necessary,  the  width  of  the 
flume  is  doubled.  The  cost  of  erecting  these  flumes  is  small,  equal  to 
about  the  cost  of  the  material  in  them.  Lumber  is  worth  $6  to  $7  per 
thousand. 


Fig.  10. — Flume,  Mills  Property,  N.  C.  Scale,  %  inch  =  l  foot.  «,  lxo-ineh  board ; 
&,  1-inch  holes ;  c,  lx3-inch  board ;  d,  wedging ;  e,  1^-inch  plank  (sides  and  bottom)  ; 
/,  2x4-inch  sills  and  cap  for  bent. 

The  water,  before  reaching  the  penstock,  flows  through  a  sand  pit 
(2,  fig.  9),  to  catch  sand,  etc.,  washed  into  the  ditch  line  from  the  side. 
It  then  enters  the  penstock  after  passing  through  a  screen  (3)  for 
removing  leaves,  sticks,  etc.  The  pipe  (5)  leading  from  penstock  is 
10-inch  spiral  riveted  sheet-steel  (with  No.  16  Birmingham  gauge), 
coated  with  coal-tar  and  connected  with  flanges.  Smaller  curves  are 
made  by  placing  cast-iron  bevelled  wings  between  the  gaskets  of  the 
flanges,  larger  ones  by  suitable  elbows.  Near  the  gravel  pit  the  10- 
inch  pipe  branches  out  through  a  Y  (6)  into  two  7-inch  pipes,  supplied 
each  with  a  gate-valve,  one  leading  to  the  giant  pen  and  the  other  to 
the  hydraulic  elevator  (7).  These  are  both  of  California  type  and  manu- 
facture.1 An  illustration  of  the  latter  in  detail  is  given  in  fig.  11.  The 
principle  of  this  device  is  too  well-known  to  require  a  description.     It 


Joshua  Hendey  Machine  Works,  San  Francisco,  Cal. 


\ 


THE    MINING    PRACTICE BURKE    COUNTY. 


Fig.  11.— Hydraulic  Gravel  Elevator,  J.  C.  Mills'  land,  Burke  Co.,  X.  C 


/ 


100 


GOLD    MINING    IN    NORTH    CAROLINA. 


is  intended  to  keep  the  elevator  stationary  as  long  as  possible,  as  its 
installation  consumes  considerable  time.  A  pit  must  be  sunk  in  the 
bed-rock,  and  as  the  elevator  must  also  drain  the  workings  (a  drain  on 
the  top  of  bed-rock  to  the  initial  point  of  working  was  considered  too 
expensive),  the  water  would  gain  too  much  headway  while  the  elevator 
is  moved.  The  work  in  the  main  pit  will  be  carried  diagonally  up  the 
banks  of  the  stream,  so  as  to  gain  as  much  grade  as  possible.  As  soon 
as  there  is  room,  a  sluice-box  (9)  will  be  placed  between  the  working 
bank  and  the  elevator-pit.     A  cross-section  of  this  is  given  in  fig.  12. 


Fig.  12. — Section  of  Sluice-box,  J.  C.  Mills  land,  Burke  Co.,  N.  C.  Scale,  >£  inchznl 
foot.  «,  1%-incb:  surfaced  pine  plank  (sides  and  bottom) ;  b,  2x4-incb  brace;  c,  2x4-inch 
sill ;  d,  lx4-incb  riffle ;  e,  lx8-inch  sand-board. 


The  upper  part  of  this  sluice  will  be  filled  with  3-inch  by  1-inch 
Mocks  and  the  remainder  with  1-inch  by  3-inch  cross-riffles,  placed  11 
inches  apart  and  held  down  by  a  sand-board,  which  is  halved  down  on 
them.  Both  will  help  to  protect  the  sluice-box  against  wear.  All 
pebbles,  etc.,  more  than  \  inch  in  diameter  will  be  forked  out  of  the 
sluices  and  left  in  the  pit  (11).  After  being  raised  by  the  elevator,  the 
material  will  pass  through  another  sluice  (8),  the  tailings  from  which 
will  be  worked  for  monazite.  It  is  expected  that  by  far  the  largest  part 
of  the  gold  will  be  saved  in  the  first  sluice. 

Active  work  was  commenced  in  July,  1895,  and  after  three  months' 
washing  with  the  giant  and  hydraulic  elevator  the  undertaking  was 
abandoned.  So  far  as  the  working  of  the  machinery  was  concerned,  the 
operations  were  entirely  successful,  but  the  yield  in  gold  and  monazite 
did  not  meet  the  expectations. 

The  f -acre  of  ground  (chiefly  tailing  dumps,  which  had  already  been 
worked  over  in  an  irregular  and  imperfect  manner  several  times)  that 
was  worked  to  an  average  depth  of  9  feet,  yielded  $350  in  gold,  and  the 
monazite  was  so  full  of  magnetite,  rutile,  etc.,  that  its  saving  was  not 
warranted. 

It  is  by  no  means  intended  by  this  to  condemn  the  property,  for  it  is 
of  course  unjust  to  judge  its  value  from  this  single  test;  and  while  it  is 
undoubtedly  true  that  the  resources  are  insufficient  to  support  a  com- 
pany organized  on  so  large  a  capitalization  as  this  English  company  was, 
there  is  no  reason  why  smaller  operations  should  not  be  entirely  suc- 
cessful. 


THE    MINING  PRACTICE.  101 

PLACER    DEPOSITS    ON    PARKER    BRANCH. 

The  Magazine  or  Parker  branch  is  a  tributary  of  South  Muddy  creek. 
Its  source  is  at  the  foot  of  Pilot  Knob,  and  from  the  latter  several 
gravel  channels  run  towards  it,  sometimes  entirely  covered  with  soil, 
so  as  to  make  their  location  unrecognizable  at  the  surface.  One  of 
these,  the  Magazine  channel,  has  been  extensively  worked,  first  by  open 
hydraulic  work,  and  afterwards  at  the  upper  end,  where  the  over-burden 
grew  too  heavy,  by  a  tunnel,  subsequently  connected  with  the  shaft. 
The  former  had  a  total  length  of  600  feet,  and  the  latter  a  depth  of  50 
feet.  The  creek  bed  has  also  been  worked,  mainly  with  rockers.  It 
was  proposed  to  work  this  bottom,  besides  any  side-hill  channels  that 
might  be  found,  by  giant,  sufficient  fall  being  available  to  carry  off  the 
tailings  in  a  continuous  sluice-box  below.  Water  for  this  work  was 
brought  a  distance  of  5  miles  to  a  large  reservoir  on  the  divide  between 
South  Muddy  and  Silver  creeks,  and  from  here  in  2  miles  of  ditch  and 
flume,  along  the  foot  of  Pilot  Knob,  to  a  reservoir  situated  100  feet  above 
the  creek  bottom.  This  reservoir  was  designed  to  hold  the  water  con- 
tained in  the  ditch  after  the  gate  at  the  large  reservoir  had  been  closed 
in  the  evening ;  and  this  was  to  be  the  first  water  to  be  used  in  the  morn- 
ing before  that  from  the  large  reservoir  had  time  to  reach  this  point. 
The  placer  deposit  in  the  creek  bed  has  a  total  width  of  400  feet.  The 
old  gravel  banks,  etc.,  were  to  be  broken  down  and  the  material  run  into 
sluices  similar  to  those  described  above,  the  tailings  being  carried  down 
the  branch  to  South  Muddy  creek. 

These  operations  were,  however,  never  undertaken,  owing  to  the 
liquidation  of  the  company  before  that  point  was  reached. 

THE   CHESTATEE    COMPANY,   LUMPKIN   COUNTY,   GA. 

The  work  pursued  here,  and  its  ultimate  object,  present  special  fea- 
tures of  interest,  and  might  warrant  a  greater  application  in  the  Southern 
gold-fields.  The  plant  and  property  of  this  company  are  situated  2-J 
miles  from  Dahlonega,  on  the  Chestatee  river,  about  -J  mile  above  the 
entrance  of  Yahoola  creek.  The  property  comprises  about  250  acres  of 
placer  ground  on  the  banks  of  the  river,  together  with  about  1  mile  of 
the  stream  bed.  The  main  object  in  view  was  to  turn  the  river  into  a 
new  channel  and  to  work  the  stream-gravel,  as  well  as  that  in  the  adja- 
cent bottoms. 

At  the  lower  end  of  the  property  a  dam  was  thrown  across  the  river 
and  a  substantial  and  well-constructed  power  station  erected,  supplying 
the  power,  by  means  of  two  66 -inch  Leffel  wheels,  for  a  Blake  duplex 
12-inch  by  24-inch  pump  and  a  50  horse-power  dynamo.  The  Leffel 
wheels  were  originally  installed  to  furnish  motor-power  to  a  centrifugal 


102  GOLD    MINING    IN    GEORGIA. 

sand-pump  for  raising  gravel  from  the  channel  excavation,  but  this  was 
later  on  abandoned  in  favor  of  a  hydraulic  gravel  elevator.  The  substi- 
tution was  made  for  economic  reasons  as  well  as  for  the  fact  that  the 
latter  had  in  its  favor  greater  simplicity,  more  constant  work,  and  easier 
portability,  as  well  as  greater  facility  of  installation. 

This  elevator  is  the  design  of  Mr.  W.  R.  Crandall,  the  general  man- 
ager of  the  Chestatee  Company.  It  combines  cheapness  and  compact- 
ness of  construction,  and  a  novel  feature  is  the  introduction  of  air  at  the 
nozzle  whenever  the  inlet  of  the  suction-pipe  is  entirely  submerged.  Its 
mechanism  and  operation  have  been  admirably  described  and  illustrated 
in  a  paper  by  Mr.  Crandall,  presented  at  the  Pittsburgh  meeting  of  the 
American  Institute  of  Mining  Engineers  in  February,  1896.  \Ye  be- 
lieve that  this  form  of  elevator  may  have  quite  an  extended  and  useful 
application  in  many  parts  of  the  Southern  field,  and  in  order  to  intelli- 
gently bring  it  before  those  of  our  readers  to  whom  the  Transactions  of 
the  American  Institute  of  Mining  Engineers  may  be  inaccessible,  we 
cannot  do  better  than  to  repeat  the  descriptive  portions  of  Mr.  Crandall's 
paper,1  changing  the  numbers  of  the  figures  to  suit  this  report: 

H^"Fig.  13  shows  the  elevator  in  detail;  Fig.  14,  the  manner  in  which  it  is  set;  Fig.  15 
the  details  of  the  flume,  etc.  In  all  the  figures  the  parts  are  lettered  respectively  as  fol- 
lows : 

A.  Cast-iron  elbow  at  the  base  of  the  elevator. 

B.  Wings  or  vanes,  to  straighten  the  water  before  it  enters  the  nozzle. 

C.  Nozzle. 

D.  Air-cap. 

E.  Air-inlet  pipe,  to  furnish  air  when  the  bottom  of  the  discharge-pipe  is  submerged. 

F.  Studs  to  support  the  discharge-pipe  and  to  keep  it  and  the  nozzle  in  line. 

G.  Cast-iron  flanged  throat. 
H.      Discharge-pipe. 

I.  Discharge-box. 

K.  Hood  for  discharge-box. 

L.  Adjustable  wood-packing  around  discharge-pipe. 

M.  Discharge-flume. 

N.  Adjustable  flume-supports. 

This  elevator,  as  used  at  the  Chestatee  mine,  near  Dahlonega,  Ga.,  where  it 
has  been  gradually  developed  and  perfected  under  the  needs  of  practice,  consists 
essentially  of  an  elbow,  A,  longer  at  one  side  than  the  other,  and  coupling  by 
means  of  a  flange  to  a  5-inch  pipe.  At  the  other  extremity  are  a  flange,  into 
which  the  nozzle  screws,  and  three  studs,  F,  which  support  the  throat  into 
which  the  gravel  and  water  enter  to  be  elevated.  The  throat  slips  inside  the 
6-in.  lap-welded  pipe,  H,  for  discharging  into  the  flume  on  the  bank,  from 
which  it  may  be  conveyed  wherever  desired. 

The  whole  apparatus,  except  the  discharge-pipe,  may  be  readily  carried  by 
two  men.  If  it  be  necessary  to  move  the  elevator  often,  to  keep  up  with  the 
drainage,  the  portable  character  of  the  outfit  is  a  great  advantage. 

At  the  Chestatee  mine  the  practice  is  about  as  follows:  The  water-supply  is 
conducted  to  the  mine  through  a  9- inch  pipe.  At  a  suitable  point  the  water  is 
divided,  and  a  5-inch  pipe  conveys  that  used  by  the  lift,  while  a  7-inch  pipe 
conducts  to  the  giant.     Valves  are  provided  at  the  Tee,  so  that  one  or  both 

1  Trans.  Am.  Inst.  Engs.,  xxvi,  1897,  pp.  62-68. 


THE    MINING    PRACTICE. 


103 


HYDRAULIC     LIFT 

DESIGNED    BY 

"W.  R.  Crandall,  July,  1895. 

{Patent,  applied  for) 


Fig.  13.— Plan  of  Hydraulic  Lift. 


i 


104:  GOLD    MINING    IN    GEORGIA. 

may  be  shut  off  as  necessity  requires.  The  lift  is  set  into  the  slate  to  such 
depth  as  may  be  desired,  and  connection  is  made  with  the  water-supply  pipe. 
The  discharge-pipe  is  then  slipped  over  the  throat  and  the  discharge-flume  is 
put  in  place,  the  discharge-pipe  being  set  at  such  an  angle  of  inclination  as 
may  be  necessary  to  give  proper  grade  to  the  tailings-flume  and  allow  the  pipe 
to  extend  a  few  inches  through  the  bottom  of  the  hooded  box. 

The  air-pipe,  E,  is  then  screwed  into  place,  and  the  lift  is  ready  for  opera- 
tion. We  govern  the  depth  to  which  we  set  the  lift  into  the  bed-rock  slate  by 
the  hardness  or  softness  of  the  latter.  If  it  be  hard,  frequent  moving  is  cheaper 
than  cutting  slate-drains.  If  soft,  we  go  as  deep  as  the  slate  will  stand  without 
timbering.     This  we  find  to  be  about  7  feet. 

A  main  drain  is  then  started  in  the*  general  direction  of  our  work,  from 
which  laterals  are  afterwards  cut  as  required;  and,  at  some  suitable  place 
near  the  lift-pit,  a  box  about  6  feet  long  by  32  inches  wide  is  set  into  the 
drain  at  grade,  and  in  this  is  placed  a  cast-iron  "  grizzly  "  having  round  holes 
2%  inches  in  diameter.  This  catches  any  rocks  which  may  escape  the  forkers, 
and  insures  that  nothing  will  get  to  the  lift  which  will  not  readily  pass  through 
the  throat,  which  has,  when  new,  an  opening  of  three  inches. 

We  use  straight-bar  riffles  in  the  discharge-flume  to  catch  any  gold  that 
may  pass  through  the  lift.  This  we  find  in  practice  to  be  about  5  per  cent,  of 
the  total  amount  recovered,  a  result  largely  due  to  the  fact  that,  when  work 
is  started  at  a  new  pit,  the  ground-sluices  are  not  long  enough  to  settle  the 
gold  thoroughly. 

Whenever  the  drainage  afforded  by  a  pit  is  exhausted  the  pipe-line  is 
extended,  a  new  pit  is  sunk  near  the  gravel-breast,  and  the  work  is  continued 
as  before. 

As  the  work  follows  the  general  course  of  the  river,  the  tailings  are  dis- 
charged into  the  river  at  the  nearest  point,  the  portable  tailing-flume  being 
extended  far  enough  to  insure  the  safety  of  the  immediate  bank.  The  tailings 
finally  flow  through  a  ditch  into  the  river. 

We  usually  use  about  200  feet  of  5-inch  pipe  in  the  lift  water-supply  before 
extending  the  9-inch  pipe-line;  and  we  often  move  up  100  feet,  dig  the  pit,  re-set 
the  lift  and  get  ready  for  work  again  in  one  12-hour  shift  with  5  men. 

As  to  the  work  which  the  lift  will  accomplish,  I  may  say  that  we  are  using  a 
lift  with  l^-inch  nozzle,  discharging  through  a  3-inch  throat  into  a  6-inch  pipe, 
and  lifting  an  average  of  18  feet  vertically,  with  water  at  about  60  pounds 
pressure  per  square  inch. 

As  we  are  quite  near  the  river,  and  have  the  drainage  of  a  side-hill,  the 
surface-water  is  considerable,  probably  fifty  gallons  per  minute.  We  use  a 
l^-inch  nozzle  on  the  giant,  and  the  lift  readily  handles  all  this  and  all  the 
dirt  and  gravel  we  are  able  to  wash  to  it.  The  latter  we  estimate,  from  meas- 
urements taken  at  different  times,  to  be  about  y2  cubic  yard  per  minute  of 
'  topping.'  The  quantity  of  gravel  is  hard  to  determine,  owing  to  varying 
conditions;  but  it  is  safe  to  say  that  it  is  all  that  the  amount  of  water  em- 
ployed will  wash." 

Water  is  supplied  to  both  the  elevator  and  the  giant  by  direct  pressure 
(about  60  pounds  to  the  square  inch)  from  the  Blake  pump.  This 
direct  appliance  of  pressure,  without  intermediate  stand-pipe  or  reser- 
voir, has  proved  very  successful,  the  only  precaution  necessary  being  to 
shut  off  the  pump  before  closing  the  feed  of  the  giant  or  elevator.     It 


THE    MINING    PRACTICE. 


105 


PLAN  OF  SETTING 

HYDRAULIC     LIFT 

as  practiced  at  the  Chestatee  Mine 

Lumpkin  Co.,  Ga. 

Scale  1  in.  =  6  feet.  W.  R.  Crandall,  Snpt. 


Fig.  14.— Plan  of  setting  Hydraulic  Lift. 


1     ELEVATION 


I     END  VIEW 


(  ) 


I    GROUND   PLAN 


M    END  VIEW 


S 


a 


L    GROUND    PLAN 


L    ELEVATION 


K    ELEVATION 


N     SIDE     VIEW 


END  VIEW 


K    GROUND    FLAN 

Fi°\  15. — Portable  Tailings-Flume 


DETAILS    OF 
PORTABLE     TAILINGS-FLUME 
as  used  at  Chestatc  i 
Lumpkin  Co-,Ga. 

Scale  1  iu.  =  o  feet.  W.  R.  CfU    tall,  S 


106  GOLD    MINING    IN    GEORGIA. 

lias  also  this  advantage,  that  when  occasion  demands  it,  smaller  nozzles 
can  be  used  and  the  pressure  thus  increased. 

The  channel  is  cut  30  to  35  feet  wide,  down  to  bed-rock  in  depth, 
and  has  a  total  length  of  about  half  a  mile.  It  runs  almost  parallel  to 
the  river,  and  from  50  to  200  yards  from  the  north  bank  of  the  same. 
When  completed,  the  waters  of  the  river  will  be  turned  into  it  by  means 
of  a  wing-dam. 

The  gravel  above  the  bed-rock  in  this  channel  is  auriferous  and  has 
paid  the  expenses  of  the  preliminary  excavations.  It  averages  1  foot  in 
thickness,  with  6  to  10  feet  of  over-lay.  The  latter  was  worked  off  during 
the  night  shift  (using  electric  light  illumination),  and  the  gravel  thus 
exposed,  as  well  as  about  2  inches  of  bed-rock,  taken  up  during  the 
succeeding  day. 

CHESTATEE  RIVER  DREDGE-BOATS,  LUMPKIN  COUNTY,   GA. 

Dredge-boats  of  various  descriptions  have  been  at  work  on  the  Ches- 
tatee  river  for  a  number  of  years.  The  work  has  been  spasmodic,  and 
failures  are  more  often  recorded  than  successes.  The  river,  where  oper- 
ated on,  is  about  100  feet  in  width  and  of  variable  depth.  Xumerous 
shoals  make  dredging  difficult. 

A  steam  vacuum  dredge  *  was  operated  for  a  time  on  this  river;  it  did 
good  work,  especially  in  cleaning  up  the  bed-rock.  The  main  difficulty, 
and  the  reason  for  abandonment,  was  the  banking  up  of  the  tailings 
around  the  boat,  finally  hemming  it  in. 

The  Hoy  Stone  method,2  using  the  principle  of  the  hydraulic  eleva- 
tor, was  attempted  as  early  as  1883,  but  proved  unsuccessful.  In  the 
summer  of  1895  there  were  two  dredge-boats  on  the  river,  one  above 
and  the  other  below  New  Bridge.  The  former  of  these,  operated  by 
Mr.  Frye,  is  on  the  principle  of  a  continuous  bucket  elevator.  So  far 
it  has  not  been  operated  successfully,  the  buckets  and  continuous  link- 
chain  proving  entirely  too  light  for  the  work.  The  other  boat  was  op- 
erated at  a  small  profit  by  Mr.  Jacquish.  It  was  erected  seven  years 
ago  by  the  Bucyrus  Steam  Shovel  Company  at  an  initial  cost  of  about 
$15,000.  After  being  worked  for  two  years  it  lay  idle  until  the  summer 
of  1895. 

The  machinery  is  installed  on  a  scow,  26  by  70  feet,  drawing  3-J  feet 
of  water.  It  consists  of  a  Bucyrus  shovel  (scoop)  of  1J  tons  capacity, 
derrick  and  hoisting-drums  for  operating  the  same,  a  small  horizontal 
engine  and  a  centrifugal-pump  for  supplying  fresh  water  to  wash  the 
gravel,  and  a  60  horse-power  locomotive  boiler.  A  barge,  100  by  20 
feet,  lying  alongside  of  the  dredge-boat,  carries  the  sluices.     There  are 

1  See  Gold,  by  A.  G.  Locke,  1882,  p.  890. 

2  See  R.  W.  Raymond,  in  Trans.  Am.  Inst.  Min.  Eng.,  vol.  viii,  p.  254. 


THE    MINING    AND    MILLING    PRACTICE.  107 

two  lines  of  sluice-boxes,  each  3  feet  wide  and  18  inches  high,  running 
the  full  length  of  the  barge,  and  filled  with  longitudinal  riffles,  made 
up  in  five-foot  racks,  composed  of  1  by  3-inch  slats  set  1  inch  apart.  The 
gravel  is  discharged  from  the  shovel  on  an  iron-shod  platform  at  the 
head  of  these  boxes,  where  the  boulders  and  larger  pebbles  are  removed. 
The  gold  is  caught  almost  entirely  in  the  upper  two  racks;  the  tailings 
run  off  into  the  river  in  the  back  of  the  boat.  "When  in  favorable 
ground,  the  dredge  will  scoop  and  deliver  an  average  of  1  bucket  every 
2  minutes.  "When  examined  there  were  3  men  on  the  dredge-boat,  engi- 
neer, fireman  and  craneman,  and  6  men  at  the  sluice-boxes.  Work  is  car- 
ried forward  up  stream,  the  scow  being  moved  against  the  current  by  an- 
choring the  scoop  and  pulling  the  scow  towards  it  by  means  of  the  crane 
engine.  The  main  wear  and  tear  are  on  the  lip  of  the  scoop,  and  on  the 
chains.  A  steel  lip  12  inches  in  length  wears  out  in  about  six  months. 
The  river  ground  is  leased  on  a  royalty  of  from  5  to  10  per  cent,  by  the 
property  owners.  It  is  said  that  gravel  as  low  as  5  cents  per  cubic  yard 
can  be  worked  at  a  profit. 

In  the  spring  of  1896  a  boat,  equipped  with  a  Marion  Steam  Shovel 
Company's  dredging  outfit,  was  in  operation  under  the  management  of 
Messrs.  Benham  and  Helmer.  A  pontoon  alongside  of  the  dredge  car- 
ried a  line  of  sluice-boxes.  The  material  from  the  dredge  was  dumped 
on  a  grizzly  at  the  head  of  the  sluice  line  and  washed  down  by  a  stream 
of  water  from  a  ~No.  8  Held  and  Cisco  centrifugal  pump  having  a 
capacity  of  4500  gallons  per  minute.  The  sluice-boxes  were  70  feet 
in  length,  64  inches  wide  and  12  inches  deep,  and  provided  with  riffles. 
There  was  a  device  for  carrying  back  the  tailings  and  depositing  them 
in  the  excavation  behind  the  machine.  The  efficiency  of  the  dredge  was 
stated  to  be  800  to  1200  cubic  yards  per  10  hours.  The  expenses  were 
estimated  at  about  $18  per  day,  and  the  gross  returns  at  $40  to  $120 
per  day. 

THE    DAHLONEGA   METHOD,    WITH   SPECIAL    DESCRIPTION    OF 
THE    HEDWIG   MINE. 

The  Dahlonega  method  of  mining  and  milling  is  one  which  is  par- 
ticularly adapted  to  the  large  bodies  of  low-grade  auriferous  saprolitic 
schists,  such  as  exist  in  the  Dahlonega  district  of  Georgia.  It  consists 
in  cutting  down  the  soft,  decomposed  ore-bodies  by  means  of  a  hydraulic 
giant,  the  water  from  which  carries  the  material  through  a  line  of  sluices 
to  the  mill  situated  some  distance  below  the  workings,  usually  on  the 
banks  of  a  stream  from  which  it  derives  its  water-power.  In  the  mill 
the  coarser  and  heavier  portions  are  retained  by  means  of  a  screen,  and 
are  fed  to  the  battery  by  hand,  the  mud  and  fine  silt  being  carried 
through  into  the  river.      Generally,  a  third  of  the  gold  saved  is  caught 


108  GOLD    MINING    IN    GEORGIA. 

in  the  riffles  of  the  mine-sluices,  the  remainder  being  obtained  in  the 
mill. 

HISTORICAL    NOTES. 

The  Dahlonega  method  first  originated  in  1868  by  sluicing  the  ma- 
terial from  the  mines  to  platforms  near  the  mill,  from  where  it  was 
hauled  to  the  mill  in  carts.  This  was  improved  by  placing  bins,  with 
perforated  bottoms,  in  the  stamp-mills,  from  4  to  5  feet  above  and  back 
of  the  mortars;  underneath  this  bin  was  a  settling-box,  in  which  the 
sandy  material  settled  and  the  slimes  overflowed.  At  the  Child's  mill, 
near  Nacoochee,  a  plant  was  erected,  consisting  of  a  series  of  washing 
and  sizing  plate-screens,  in  which  three  sizes,  coarse,  medium  and  sand, 
were  made  and  milled  separately.  It  is  stated  that  all  the  millable  ore 
was  saved  in  this  way,  in  a  clean  shape,  free  from  mud. 

The  present  practice  is  to  flush  the  material  on  to  the  mill  floor  back 
of  the  batteries,  this  space  in  the  mill-house  being  practically  arranged 
as  a  large  bin  with  a  slat  screen  (distance  between  slats  about  -J  inch) 
at  one  end.  Frequently  a  Y-shaped  storage-tank  is  situated  outside  of 
the  mill,  where  the  material  is  collected  and  flushed  into  the  mill  as 
occasion  requires. 

THE   WATER-SUPPLY. 

The  system  of  reservoirs,  ditches,  etc.,  in  this  district  is  by  far  the 
most  extensive  and  best  equipped  in  the  Southern  gold-belt.  The  prin- 
cipal water-line  is  known  as  the  Hand  and  Barlow  ditch,  having  a  total 
length  of  34  miles,  the  main  canal  being  20  miles  long,  6  feet  wide  and 
3  feet  deep,  and  furnishing  800  miners'  inches.  The  grade  averages  5 
feet  to  the  mile,  being  4^  feet  on  straight  lengths,  with  slightly  steeper 
grades  on  bends.  The  cost  of  digging  this  canal  was  about  $1  per  rod; 
the  total  cost,  including  trestling,  etc.  (excluding  syphon-line),  was 
$1000  per  mile.  The  canal  crosses  the  Yahoola  valley  about  1  mile 
northeast  of  Dahlonega,  in  a  wrought-iron  syphon-tube  (see  Plate  VIII) 
2000  feet  in  length.  The  difference  in  level  of  the  two  ends  is  about 
6  feet,  and  the  pressure  at  the  lowest  point  is  90  pounds  per  square 
inch.  The  inside  diameter  is  3  feet,  the  thickness  of  the  pipe  being  i\ 
inch  in  the  upper  and  f  inch  in  the  lower  part.     It  was  built  in  IS 69. 

Tour  miles  from  Dahlonega  the  water  is  carried  across  a  similar  de- 
pression in  a  wooden  tube  which  is  -g-  of  a  mile  in  length  and  3  feet  in 
outside  diameter.  It  is  made  of  3  by  5-inch  staves,  trimmed  so  as  to 
make  a  tight  fit.  These  staves  are  laid  in  wrought-iron  hoops,  forming 
alternate  joints;  the  last  stave  is  driven  in  with  a  maul.  This  tube  was 
built  in  1868,  and  is  still  in  good  condition. 

Auxiliary  ditches  run  off  from  the  main  canal  to  the  various  mines. 
A  portion  of  this  water  was  formerly  leased  out  at  the  rate  of  12  cents 
per   miner's   inch   for   24  hours.     The   present   owners,   The   Hand   & 


fiM* 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  10,  PLATE  VIII. 


WROUGHT-IRON   SIPHON    PIPE  (3  FEET   INSIDE   DIAMETER),  2000   FEET   LONG,   ON   THE  HAND 
BARLOW   DITCH    LINE,   CROSSING  THE  YAHOOLAH   RIVER.  ONE   MILE   FROM    DAHLONEGA,   GA. 


\ 


t 


i,  >,/'i 


'*'.;■  J'fJ  ••■■** 


JM 


THE    MINING    AND    MILLING    PRACTICE.  109 

Barlow  United  Gold  Mines  and  Hydraulic  Works  of  Georgia,  have, 
however,  been  lately  using  the  whole  amount  in  working  their  own 
mines.  Besides  this  system  there  are  several  smaller  ones,  bringing 
the  total  length  of  ditch-lines  up  to  about  80  miles. 

A  unique  feature  of  the  water-supply  at  the  Findley  mine  is  the 
elevation  of  the  water  from  the  ditch-line  to  a  reservoir  situated  152  feet 
above  it,  by  means  of  a  hydraulic  pumping  engine  made  by  the  Filer  & 
Stowell  Company,  of  Milwaukee,  Mich.  This  pump  is  situated  near  the 
stamp-mill,  285  feet  below  the  ditch-line.  The  water  is  led  to  it  from 
the  above  ditch  in  a  16-inch  straight-riveted  feed-pipe  456  feet  in 
length,  and  is  discharged  by  it  into  a  reservoir  of  88,000  cubic  feet 
capacity,  a  total  vertical  height  of  437  feet,  through  a  12-inch  steel  pipe 
1141  feet  in  length.  The  principle  involved  is  that  of  the  hydraulic 
ram,  inasmuch  as  a  large  quantity  of  water  under  a  lower  head  raises 
a  certain  portion  of  itself  to  a  higher  head,  the  remainder  being  waste. 
The  machine,  however,  is  of  entirely  different  and,  so  far  as  known, 
novel  construction.  It  is  of  the  duplex  pattern,  the  two  engines  being 
-connected  by  gearing  and  with  an  8-foot  fly-wheel.  Each  engine  has  3 
•cylinders  in  tandem,  to  which  the  water  under  the  feed-head  (123 
pounds)  is  admitted  and  discharged  by  valves  of  the  Hiedler  type.  In 
one  of  these  cylinders  the  water  is  raised  to  the  greater  head  (190 
pounds)  at  the  expense  of  the  feed-water,  under  head,  going  to  waste  in 
the  other  two.  A  snifting-valve  is  attached  to  the  latter  to  give  relief 
to  the  valves.  The  stroke  is  18  inches,  and  at  a  high  piston-speed  of 
250  feet  per  minute  the  pump  works  very  smoothly.  Tests  had  not 
been  made,  and  no  figures  of  efficiency  could  be  obtained  at  the  time  of 
our  visit.  Such  figures,  as  well  as  a  more  detailed  description  than 
could  be  made  after  a  hasty  examination,  would  be  of  great  interest. 
The  present  working  capacity  of  the  pump  is  600  gallons  per  minute. 

MINING    METHODS. 

The  general  character  of  the  ore-bodies  has  already  been  described  (pp. 
22  and  23).  The  depth  of  the  saprolites  (decomposed  schists)  in  the 
Dahlonega  region  reaches  often  to  50  and  sometimes  100  feet.  Enor- 
mous openings  have  been  made  in  these  by  the  hydraulic  giant,  whole 
sides  of  the  mountain  being  torn  off  in  places  (see  Plate  IX).  The 
head  employed  in  hydraulicking  varies  from  50  to  150  feet,  dependent 
on  the  height  from  which  water  can  be  obtained.  Where  harder  rock 
"is  torn  loose,  it  is  broken  by  hand-sledges  and  thrown  into  the  ground- 
sluices.  Powder  is  sometimes  resorted  to  for  breaking  down  the  more 
resistant  ledges.  In  order  to  shorten  the  distance  in  sluicing  to  the 
mill,  tunnels  are  often  run  through  the  intervening  hill-  (as  at  the 
Hand  and  Eindley  mines).  The  wooden  sluice-line  is  supplied  with 
longitudinal  riffles  throughout  its  entire  extent. 


110 


GOLD    MINING    IN    GEORGIA. 


In  the  pursuance  of  this  method  a  large  proportion  of  the  material 
carried  to  the  mill  is  perfectly  barren,  for  the  reason  that  the  entire 
mass  is  not  gold-bearing,  but  only  certain  streaks  of  it,  which  cannot  be 
mined  separately  by  this  method. 

I 


Fig.  16. — Vertical  Cross-section  of  the  450-pound  Hall  Stamp-mill. 
MILLING    METHODS. 

The  Dahlonega  method  of  mining  and  the  milling  material  resulting 
from  the  same  have  developed  a  milling  practice  particularly  character- 
istic of  this  district.  The  material  floated  to  the  mill  is  of  necessity  of 
small  size,  the  larger  pieces  of  rock  being  sledged  before  entering  the 
flume.     Thus   crushing  is  dispensed  with.     Automatic   feeders   at  the 


THE    MINING    AND    MILLING    PRACTICE. 


Ill 


mill  have  been  tried,  but  were  found  impracticable,  the  variable  hardness 
of  the  ore  (only  a  small  proportion  being  hard  quartz  and  rock)  making 
hand-feeding  imperative. 

The  battery  which  is  almost  universally  in  use  is  that  of  the  Hall  type, 
invented  and  patented  by  Mr.  Frank  W.  Hall,  of  Dahlonega.  The 
usual  weight  of  the  stamp  is  450  pounds.  Figs.  16  and  17  give  the 
two  vertical  sections  of  this  mill.  It  represents  novel  features  both  in 
the  battery  and  in  the  setting.  The  long  battery  blocks  and  a  bed-rock 
foundation  have  been  entirely  dispensed  with.  The  mill  can  be  set  upon 
any  level  piece  of  ground,  a  2-inch  plank  platform  forming  practically 
the  only  foundation.  The  plan  of  construction  (well  shown  in  the 
drawing)  makes  the  frame  self-contained,  the  blow  of  the  stamp  and  the 
reaction  being  absorbed  and  neutralized  in  the  setting.  Elasticity  is 
maintained  by  the  guy-rods.  A  suspended  platform  gives  access  to  the 
props,  cams,  etc.  The  mortar  is  held  in  place  by  a  rib  on  the  bottom 
fitted  in  a  corresponding  gain  in  the  mortar  block.  It  is  held  down  on 
the  latter  by  wedges  driven  against  blocks  bolted  on  the  inside  of  the 
battery  posts.  The  small  inside  dimensions  of  the  mortar  are  still  more 
narrowed  down  by  chilled-iron  liners,  which  reach  to  within  an  inch  of 
the  dies.  The  main  purpose  of  these  liners  is  to  bring  the  ore,  on  being 
fed,  immediately  under  the  shoes.  They  also  protect  the  mortar  against 
wear,  and  help  to  some  extent  in  collecting  and  secreting  amalgam. 
Quicksilver  is  fed  to  the  batteries,  and  in  some  cases  a  considerable 
amount  of  amalgam  collected  is  obtained  from  the  mortars.  The  liners 
are  fitted  with  dovetails  and  lugs  at  the  end,  and  are  finally  held  in 
place  by  two  large  keys  driven  against  the  screen  frame,  which  is  shod 
with  wear  iron  on  each  side.  On  removing  the  front  liner  the  mortar 
is  opened  to  the  floor.  The  dies,  which  sit  in  ^-inch  depressions,  are 
easily  withdrawn,  the  back  and  side  liners  drop  out,  and  the  mortar  can 
be  cleaned  in  a  few  minutes.  The  whole  clean  up  in  a  10-stamp  mill 
is  accomplished  in  the  space  of  half  an  hour.  The  front  liner  deter- 
mines the  height  of  discharge,  which,  when  the  dies  are  new,  is  about 
2  inches.  An  annealed  copper  plate,  4  feet  long  and  of  the  full  width 
of  the  mortar,  is  in  most  cases  considered  sufficient  for  the  outside  amal- 
gamation. The  weight  of  the  450-pound  stamp-mill  is  divided  as 
follows : 

Pounds. 

Stem  or  spindle 175 

Head  of  boss 150 

Tappet  with  keys 50 

Shoe    75 

Total  weight  of  stamp 450 

Die 50 

Mortar 2100 

;  Liners  for  same   240 


112 


GOLD    MINING    IN    GEOEGIA. 


Fig.  17 — Vertical  Longitudinal  Section  of  the  450-pound  Hall  Stamp-mill. 


^J 


THE    MINING    AND    MILLING    PRACTICE.  113 

The  average  drop  of  stamp  is  9  inches;  number  of  drops  per  minute, 
90.  The  whole  machine  is  well  constructed,  and  admirably  fulfills  its 
purpose  of  handling  large  quantities  of  the  Dahlonega  mill-stuff.  The 
mill  is  also  built  with  heavier  stamps,  and  some  slight  changes  are  made 
in  the  frames  of  these.  None  of  these  heavier  mills  were  seen  in  opera- 
tion; but  the  setting  employed  is  said  to  give  as  great  satisfaction  as  in 
the  lighter  ones.  Whether  the  application  of  this  mill  would  be  exten- 
sive for  harder  ores  we  are  unable  to  judge.  It  certainly  gives  the 
extreme  of  rapid  crushing,  and  might  be  adopted  where  such  an  object 
is  in  view. 

The  cost  of  these  mills  is  light  and  that  of  installation  small  as  com- 
pared with  those  of  Western  type.1 

Almost  all  the  mills  in  Dahlonega  are  operated  by  water-power,  using 
turbines  of  the  Lefiel  type  for  large  quantities  and  low  heads,  and  wheels 
of  the  Pelton  type  when  the  water  is  small  in  quantity  under  a  high 
head.  The  crushing  capacity  of  these  mills  varies  from  2  to  5  tons  per 
stamp  of  450  pounds  in  24  hours,  depending  greatly  on  the  nature  of 
the  material  run  through. 

In  hydraulicking,  and  subsequent  transportation  by  water,  a  partial 
concentration  takes  place,  resulting  in  the  eventual  deposition  of  a 
largely  enriched  product  in  the  mill.  The  light  stuff  and  most  of  the 
slimes  pass  through  the  mill,  in  almost  all  cases  without  subsequent 
treatment,  and  the  heavy  product'  remains,  the  enriching  being  all  the 
way  from  2  to  5  times  the  original  value  of  the  ore  in  place.  Besides 
this,  free  gold  (generally  about  one-third  of  the  total  amount  saved)  is 
caught  in  the  sluices  before  reaching  the  mill.  Some  of  the  losses  in 
this  process  are  evident  from  the  above.  Another  serious  loss,  which  is 
rapidly  making  itself  felt  as  the  mines  grow  deeper  and  less  decomposed 
ores  occur,  is  that  of  gold  in  the  sulphurets.  In  such  ores  that  carry 
sulphurets  at  all  it  is  stated  that  they  will  run  from  2  to  10  per  cent., 
the  concentrates  from  which  are  reported  to  assay  as  high  as  $40  and 
higher.     Thus  far,  concentration  has  not  been  carried  out  on  a  working 

1  The  following  figures  were  obtained  in  the  camp  as  representing  the  average  cost  of  a  450- 
pound  10-stamp  mill  of  the  Hall  type,  as  erected  and  used  in  the  Oahlonega  district : 
All  iron-work  for  batteries  and  setting,  including  copper-plates  (f.  o.  b. 

works,  Cincinnati) $700  00 

Freight  on  same,  and  cost  of  erection,  about 500  00 

Buildings,  floors  and  sluices ' 400  00 

Engine  and  boiler,  with  connections 600  00 

Freight  on  same,  about ■ 150  00 

Total  cost  of  complete  mill $2350  00 

Water-wheel  and  installation  of  same  would  cost  about  the  same  as  engine  and   boiler. 
Chrome  steel  (made  in  Brooklyn,  N.  Y.)  and  Wilson  pressed  steel  (made  in  St.  Louis,  Mo.)  shoes 
and  dies  find  about  equal  favor  in  the  district,  costing  respectively  6  and  7  cents,  f.  o.  b.  works. 
Cast-chilled  iron  shoes  are  also  used  to  some  extent,  at  a  cost  of  about  3  cents  per  pound. 
Mills  similar  to  the  Hall  type  are  also  made  in  Gainesville  and  Atlanta,  Ga. 
8 


114  GOLD    MINING    IN    GEORGIA. 

basis.  Despite  many  inquiries  amongst  local  mill-men  and  others,  we 
could  hear  no  reports  of  losses  in  amalgamation  resulting  from  so-called 
rusty  gold.  A  loss  of  this  nature  was  in  a  few  cases  ascribed  to  the 
finely-divided  or  flaky  condition  of  the  gold. 

It  is  difficult  to  give  any  average  values  of  the  Dahlonega  ores,  or  in 
fact  to  clearly  designate  exactly  what  the  term  ore  applies  to  in  this  dis- 
trict. Material  worth  as  low  as  40  cents  per  ton  has  been  milled  at  a 
profit.  If  this  figure  per  ton,  plus  the  gold  saved  in  the  sluices  (20 
cents  per  ton  milled)  represents  the  milling-value  of  5  tons  of  material 
mined,  as  is  stated  to  be  frequently  the  case,  then  the  value  of  the  latter 
per  ton  must  have  been  12  cents.  As  a  rule,  however,  the  mill-stuff  is 
of  better  grade  than  the  above.  The  actual  ore  (quartz)  is  stated  to 
assay  from  $1  up  to  exceptionally  high  values  in  the  cases  of  rich 
stringers  or  pockets. 

The  cost  of  mining  and  milling  throughout  the  district  will  average 
from  18  to  25  cents  per  ton  of  ore  milled. 

A  description,  somewhat  more  in  detail,  has  been  prepared  of  the 
following  mine  as  representing  perhaps  most  perfectly  the  Dahlonega 
method  in  its  original  type  (of  working  .soft  saprolites  or  highly  decom- 
posed material). 

DAHLONEGA  METHOD  AT  HEDWIG  MINE. 

The  Hedwig  mine  is  situated  near  Auraria  six  miles  west  of  Dahlo- 
nega, It  consists  of  a  large  open  cut  about  sixty  feet  in  depth, 
run  on  a  line  of  siliceous,  micaceous  ore-bearing  schists,  sixty  feet 
in  total  width.  The  strike  of  the  sckistosity  is  N.E.  and  the  dip 
60°  S.E.  Three  separate  ledges  of  barren  hornblende-gneiss  (brick- 
bat) enclose  two  ore-bodies,  striking  and  dipping  conformably  To  them. 
But  very  few  small  quartz-stringers  occur  in  the  mass.  \Vater  is  fur- 
nished to  the  giant  (3-inch  nozzle)  under  a  maximum  head  of  60  feet 
from  a  reservoir  situated  on  the  hillside  above  the  mine.  Six  men  are 
employed  at  the  mine  at  80  cents  per  day  (day-shift  only). 

The  material  is  run  to  the  mill  in  a  flume  2800  feet  in  length  and  14 
by  16  inches  in  cross-section,  made  of  oak  boards.  It  is  supplied  with 
longitudinal  riffles  made  of  2  by  3-inch  post  oak  scantling.  The  grade 
of  this  sluice  is  4  J  inches  in  12  feet  at  the  lower,  and  3^  inches  at  the 
upper  end,  that  is,  in  the  cut  where  it  is  not  necessary  to  avoid  over- 
flows. The  outside  mill-bin  holds  about  240  tons,  and  the  material  is 
flushed  from  here  to  the  inside  bin,  which  holds  200  tons.  Formerly 
there  were  three  outside  bins  and  the  ore  was  hauled  to  the  mill  in  cars. 

The  mill  is  a  40-stamp  one  of  the  Hall  pattern,  with  a  12-foot  driving* 
pulley.  It  is  driven  by  a  4-inch  Bidgeway  wheel,  using  40  inches  of 
water  from  two  1-inch  nozzles.     The  water  is  supplied  from  the  same 


THE    MINING   AND    MILLING   PRACTICE.  115 

reservoir  that  furnishes  the  giant  at  the  mine,  by  an  18-inch  spiral'  riv- 
eted pipe-line,  2880  feet  in  length,  under  a  head  of  226  feet.  The 
weight  of  the  stamps  is  450  pounds;  drop  9  inches,  80  times  per  minute; 
discharge  2  inches;  round  punched  screen,  120  holes  to  the  square  inch; 
length  of  plates  (plain  copper)  8  feet  in  two  sections;  ten  of  the  stamps 
were  fitted  with  silvered  plates  in  2-foot  sections.  Only  the  upper  4 
feet  of  the  plates  in  the  mill  are  kept  in  shape;  it  is  stated  that  no  gold 
was  saved  on  the  lower  ones.  The  tailings  flow  off  through  mercury 
traps.  The  overflow  from  both  the  outside  and  inside  bins  runs  through 
a  short  line  of  riffled  sluice  boxes.  At  the  time  of  our  examination 
seven  men  were  employed  in  the  mill  in  two  shifts,  at  90  cents  per  day. 

THE   LOCKHART  MINE,   LUMPKIN   COUNTY,   GA. 

The  Lockhart  mine  is  situated  on  the  west  bank  of  the  Yahoola  river 
near  Dahlonega,  Ga,  It  represents  the  working  of  ore-bodies  of  the 
Dahlonega  type  by  underground  mining. 

The  Dahlonega  method  of  mining  the  saprolites  was  formerly  em- 
ployed here,  and  the  old  open  cuts,  now  practically  abandoned,  are  of 
considerable  extent.  This  is  the  only  mine  in  the  Dahlonega  district 
where  underground  work  of  any  importance  has  been  carried  on.  The 
ore-bodies  consist  of  veins  of  the  Dahlonega  type  (see  description,  pp.  22 
and  23)  where  the  quartz-filling  has  been  more  extensive,  in  places  occu- 
pying the  greater  part  of  the  fractured  gneiss  bands,  which  in  a  mining 
sense  may  be  termed  the  vein,  the  boundaries  of  the  gneiss  bands  form- 
ing continuous,  smooth  walls,  and  being  the  limit  of  the  mineable  ore. 
The  normal  strike  of  the  schists  at  the  Lockhart  is  northeast  and  the  dip 
southeast;  at  one  point,  however,  the  schists  bend  around  a  mass  of 
"  brickbat,"  the  strike  being  abruptly  changed  to  the  northwest  and  the 
dip  to  the  northeast. 

The  principal  work  has  been  done  on  the  Blackmore  vein,  where  the 
country  is  a  biotite  hornblende-gneiss.  The  strike  of  this  vein  is  E\E.  and 
the  dip  30°-60°  S.E.  It  varies  in  thickness  from  3  to  6  feet.  The  ore- 
body  is  opened  by  two  adit-levels  on  the  vein,  60  feet  apart.  The  lower 
one,  which  enters  the  hillside  at  a  depth  of  about  135  feet  below  the 
original  outcrop,  has  a  length  of  400  feet,  and  the  ore  has  been  stoped 
out  between  it  and  the  upper  level  for  a  distance  of  100  feet  from  the 
face,  which  is  the  length  of  the  ore-shoot  so  far  as  explored.  This 
shoot  has  also  been  worked  from  the  upper  level  to  the  surface.  The 
pitch  is  steeply  to  the  E~.E.  The  ores  from  this  shoot  mill  from  $4  to 
$5  per  ton.  Besides  this  richer  shoot  the  bottom  level  exposes  ore 
throughout  its  entire  length.  This,  however,  decreases  in  quality  as  the 
mouth  of  the  tunnel  is  approached,  where  it  yields  only  $1.  The  system 
of  work  is  underhand  stoping,  stulls  being  placed  6  feet  apart  to  1ml. 1 


116 


GOLD    MINING    IN   GEORGIA. 


up  the  ground.  The  ore  is  carried  from  the  stopes  in  barrows  to  a 
platform  at  the  mouth  of  the  tunnel,  from  where  it  is  hauled  to  the  mill 
by  carts. 

The  same  vein  has  also  been  opened  by  a  shaft,  50  feet  deep,  at  the 
mill  house,  which  is  situated  about  300  feet  N.E.  from  the  mouth  of  the 
mine.  A  drift  300  feet  long  was  run  on  the  vein  here,  which  is 
reported  to  be  14  feet  thick,  carrying  highly  sulphuretted  ores,  which 
milled  $4.     This  part  of  the  mine  is  now  under  water. 

Other  ore-bodies  have  been  opened  up  to  some  extent,  but  not  suf- 
ficiently to  say  much  of  their  nature. 

The  ore  is  treated  in  a  20-stamp  mill  of  the  450-pound  Hall  type, 
erected  originally  for  working  material  from  open  cuts  by  the  Dah- 
lonega  method.  No  crusher  or  mechanical  feeder  is  used,  and  no  con- 
centration of  the  sulphurets  has  so  far  been  attempted,  although  they 
are  stated  to  be  of  high  grade.  The  ore  is  fed  by  hand,  one  man 
attending  to  each  ten  stamps.  The  drop  is  6  to  8  inches,  60  times  per 
minute,  and  the  discharge  is  about  2  inches  high.  The  screen  used  is 
a  No.  9  Russia  slot.     The  plates  are  6  feet  in  length,  plain  copper. 

For  the  hard  ores;  such  as  are  at  present  mined,  this  mill  can  scarcely 
be  considered  of  the  best  type,  being  too  light.  A  crusher  and  auto- 
matic feeder  would  also  be  applicable  here,  as  well  as  concentrators  and 
a  subsequent  treatment  of  the  sulphurets.  The  mill-power  is  furnished 
by  a  turbine  wheel,  obtaining  its  head  of  water  from  a  dam  across  the 
Yahoola  river. 

The  cost  of  production  at  the  Lockhart  is  given  as  follows: 

Per  ton  of  ore. 

Mining $  .90 

Hauling 15 

Milling 20 

Other  expenses    10 

Total  cost  of  producing  bullion $1.35 

The  average  milling  value  of  the  ore  for  the  month  ending  February 
3,  1895,  is  given  as  $4.15  per  ton.  Eo  figures  of  the  assay-values  of 
the  tailings  could  be  obtained. 


CHAPTEE  VI. 

MINING,  MILLING,  AND  METALLURGICAL  TREATMENT 
OF  SULPHUKET  ORES  AT  CHARACTERISTIC  MINES. 

THE  REIMER  MINE,  ROWAN  COUNTY,  N.  C. 

This  mine  is  situated  about  6  miles  southeast  of  Salisbury  on  the 
waters  of  the  Yadkin  river.  Geologically  it  is  in  the  Carolina  belt.  It 
represents  a  highly  sulphuretted  quartz-vein  of  marked  persistency, 
with  smooth  walls  and  a  clay  gouge,  the  ore  from  which  is  worked  by 
st^mp-mill  amalgamation,  concentration  of  the  sulphurets,  and  chlorin- 
ation  by  the  Thies  process. 

The  vein  is  said  to  average  3-J  feet  in  thickness,  varying  from  1-J  to 
as  high  as  9  feet.  The  strike  of  the  outcrop,  which  has  been  traced 
for  2  miles,  is  in  an  east  and  west  direction.  The  dip  is  practically  ver- 
tical. The  sulphurets,  mostly  pyrite  with  a  little  chalcopyrite,  occur 
in  bunches,  averaging  about  10  per  cent,  of  the  ore.  The  quartz  is 
compact,  white  and  glassy.  The  wall-rock  is  a  coarse  crystalline  erup- 
tive, probably  a  quartz-diorite,  and  a  fine-grained  phase  of  the  same. 

Until  1884,  when  it  was  destroyed  by  fire,  a  concentration  plant  was 
in  operation  here.  The  concentrates  which  were  obtained  without  pre- 
vious  amalgamation,  were  treated  at  the  Yadkin  Chlorination  works 
near  Salisbury.  Work  wTas  not  taken  up  again  until  1894  and  lasted 
until  the  fall  of  1895.  Fig.  18  gives  a  vertical  section  of  the  mine 
along  the  strike  of  the  vein.  The  last  work  was  concentrated  at  the 
bottom  of  No.  1  shaft  (1),  at  a  depth  of  190  feet.  The  shaft  is  poorly 
constructed  and  very  wet.  A  Cornish  pump,  driven  by  a  belt  from  the 
crank  of  a  small  friction-clutch  hoisting  engine,  raised  the  water  from 
the  bottom  into  a  crude  ring  at  the  150-foot  level,  from  where  a  No.  9 
Cameron  sinking  pump  raised  it  to  the  surface.  No  development  work 
was  carried  ahead,  the  ore  being  taken  out  by  overhead  stoping  as  soon 
as  found.  It  was  stated  by  the  management  that  the  poor  condition  of 
the  mine  and  the  crude  method  pursued  was  due  to  the  more  or  less 
experimental  nature  of  the  late  underground  developments.  The  size 
and  substantial  construction  of  the  mill  and  chlorination  plant  seem, 
however,  to  have  gone  beyond  this  stage.  On  account  of  the  limited 
development  the  mine  was  worked  in  three  shifts  of  eight  hours  each. 
with  two  miners  and  helpers  on  each  shift,  paid  respectively  $1.50  and 


118 


GOLD    MINING    IN    NORTH    CAROLINA. 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MINES.        119 

$1.  The  engineer,  fireman  and  top-labor  worked  in  two  shifts  of  twelve 
hours  each.  No  definite  information  could  be  gained  regarding  the  cost 
of  mining ;  but  under  the  conditions  existing,  it  must  have  been  excessive. 
The  mill  is  a  20-stamp  one,  built  by  the  Mecklenburg  Iron  Works.1  The 
mortar  (fig.  19)  is  of  a  modified  California  type,  and  of  medium  width 
and  depth.  A  novel  feature  in  this  mortar  is  a  large  opening  above 
and  in  back  of  the  screen  by  which  the  inside  of  the  screen  can  be 
reached  to  clear  it  of  foreign  clogging  matter.  The  inside  plates  may 
also  be  taken  out  through  it  without  disturbing  the  screen.  The  weight 
of  each  stamp  is  750  pounds,  given  5-  to  7-inch  drop,  90  drops  per  min- 
ute. No  inside  plates  are  used  at  this  mill.  The  height  of  the  discharge 
is  5  inches,  when  the  dies  are  new.  The  screens  are  40-mesh,  brass  wire. 
The  outside  plates  are  similar  to  those  at  the  ITaile  mine  (see  p.  136) 
The  amount  of  ore  milled  was  about  1  ton  per  stamp  in  12  hours.  About 
it  of  the  gold  extracted  was  saved  by  amalgamation.  The  tailings  from 
the  plates  were  concentrated  on  2  Frue  and  2  Triumph  vanners,  produc- 
ing about  1  ton  of  concentrates  in  12  hours,  running  from  $30  to  $40 
per  ton. 

The  concentrates  were  roasted  in  a  large  reverberatory  furnace  located 
in  the  mill  building,  the  area  of  the  hearth  being  9x41J  feet.  The 
capacity  of  this  furnace  was  stated  to  be  4  roasted  tons  in  24  hours  at  a 
cost  of  $1.25  per  ton.  The  furnace  was  worked  in  two  12-hour  shifts 
with  two  men  on  each  shift,  head  roaster  at  $1  and  helper  at  85  cents. 
Two  cords  of  wood,  at  $1.25  per  cord,  were  burnt  in  24  hours. 

The  chlorination  was  carried  on  in  a  1-barrel  plant  with  a  capacity  of 
4  roasted  tons  of  concentrates  per  24  hours.  The  building  is  arranged 
for  the  addition  of  another  barrel  which  would  allow  the  same  work  to 
be  done  in  12  hours,  giving  better  opportunity  for  precipitation,  and 
reducing  the  total  cost  of  chlorination.  The  charge  and  the  method  of 
working  was  identical  with  that  pursued  at  the  Haile  mine  (see  p.  140). 

1  The  Mecklenburg  Iron  Works  of  Charlotte,  N.  C,  Captain  John  Wilkes,  Manager,  make  a 
specialty  of  gold-mining  and  milling  machinery.  In  the  summer  of  1895  this  company  erected 
a  5-stamp  test  mill  at  their  works,  connected  with  a  complete  chlorination  test  plant  having  a 
capacity  of  half  a  ton  of  raw  concentrates  per  day.  As  being  of  interest  and  value  in  a  paper 
of  this  kind,  we  have  obtained  from  them  the  following  list  of  the  cost  of  milling  and  chlorina- 
tion plants  erected  in  the  South.  The  figures  given  are  outside  ones  and  apply  in  each  case 
to  a  complete  automatic  plant. 

The  cost  of  the  machinery  for  a  10-750-pound  stamp  mill  with  grizzly,  crusher,  self  feeders, 
silvered  inside  and  outside  plates,  Triumph  concentrators  (4  to  every  10  stamps),  engine  and 
boiler,  together  with  all  attachments,  and  plans  for  erecting  and  locating  machinery,  is  given 
at  $5700  f .  o.  b.,  Charlotte,  N.  C    The  same  for  a  20-stamp  mill  is  $10,350. 

The  complete  cost  of  a  10-stamp  mill  as  above,  set  up  (in  the  vicinity),  will  be  about  ££000. 
Of  a  20-stamp  mill,  about  $14,000. 

The  approximate  cost  of  a  1-barrel  chlorination  plant  with  two  reverberatory  furnaces, 
erected,  is  given  at  $5500.    The  same  for  a  2-barrel  plant  with  four  furnaces  at  $9700. 

The  complete  cost  of  a  10-stamp  mill  with  concentrators,  roasting  furnaces  and  a  Thies 
chlorination  plant  with  all  necessary  power  and  expenses  may  be  figured  at  $1200  per  stamp. 
For  a  20-stamp  mill  at  $1000  per  stamp,  and  for  a  40-stamp  mill  at  $900  per  stamp. 

The  price  of  shoes  and  dies  of  a  chilled  charcoal  iron  mixture  is  3  cents  a  pound  f.  o.  b.  works. 


120 


GOLD    MINING    IN    NORTH    CAROLINA. 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MINES.        121 

"No  satisfactory  figures  regarding  the  value  of  the  tailings  from  either 
the  concentration  or  chlorination  could  be  obtained;  the  figures  given 
were  high  as  compared  with  those  of  other  mines.  The  cost  of  milling, 
concentration,  roasting  and  chlorination  per  ton  of  ore  milled  was  given 
at  $1.80  per  ton.  This  excessive  cost,  almost  three  times  as  much  as  that 
at  the  Franklin  mine,  an  almost  identical  case  as  far  as  the  plant  and  the 
thickness  of  the  ore-body  are  concerned,  must  no  doubt  be  greatly  laid 
to  the  fact  that  an  attempt  is  made  to  supply  a  plant  with  a  nominal 
capacity  of  40  tons  in  24  hours  from  a  mine,  in  which  the  development 
does  not  warrant  an  output  of  10  tons  in  this  time. 

The  percentage  and  value  of  concentrates  given  above,  with  the  addi- 
tion of  the  gold  saved  on  the  plates,  gives  an  estimated  value  of  from 
$4  to  $5  per  ton  to  the  ore  mined,  without  including  in  this  value  the 
gold  lost  in  tailings.  Such  an  ore  if  found  in  sufficiently  large  bodies 
on  developing  the  mine,  should  pay  a  profit  with  the  above  method  of 
treatment  under  a  close  management. 

Experiments  were  made  with  cyanide  in  1896,  but  were  not  successful. 

THE  FRANKLIN  MINE   (CREIGHTON  MINING  AND  MILLING  COM- 
PANY), CHEROKEE  COUNTY,  GA. 

This  mine  is  situated  on  the  Etowah  river,  about  16  miles  northeast 
of  Canton,  the  county  seat.  Geologically  it  is  in  the  Georgia  belt.  The 
proposition  presented  here  is  in  most  respects  similar  to  that  at  the 
Reimer  mine. 

The  country-rock  consists  of  gneissoid  mica-  and  hornblende-schists, 
often  garnetiferous.  The  general  strike  is  !N\  55°  E.  and  the  dip  40° 
S.E.  Granite  dikes  are  stated  to  exist  in  the  vicinity  of  the  mine,  but 
none  have  been  as  yet  found  intersecting  the  ore-bodies.  The  char- 
acter of  these  ore^bodies  has  been  described  (p.  23).  There  are  two 
parallel  veins  about  150  feet  apart,  known  respectively  as  the  Franklin 
and  the  MacDonald.  Of  these,  the  Franklin  has  been  most  extensively 
opened,  and  is  the  only  one  that  has  been  worked  during  recent  years. 
The  strike  and  dip  of  the  veins  are,  in  the  main,  coincident  with  those 
of  the  country  schists.  The  mineable  ore  exists  in  lenticular  shoots  or 
cylinders  pitching  45°  1ST.E.  (see  fig.  20).  Four  such  shoots  had  been 
opened  in  the  mine  within  a  horizontal  distance  of  about  750  feet  on 
the  strike,  at  the  time  of  our  visit.  The  largest  one  of  these  has  a  max- 
imum length  of  120  and  maximum  width  of  14  feet.  The  average 
thickness  of  the  ore-bodies  is  probably  about  3  feet.  All  but  one  of  the 
ore-shoots  crop  out  at  the  surface,  and  they  show  considerable  perma- 
nency in  depth.  The  350-foot  drift  in  the  mine  was  extended  in  a 
northeasterly  direction  about  400  feet  beyond  the  last  ore-shoot. 
Although  a  permanent  vein  with  clay  casings, and  in  places  heavy  quartz- 


J22 


GOLD    MINING    IN    GEOEGIA. 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MIKES.        123 

filling-,  had  been  found,  the  ore  was  not  rich  enough  to  mill.  On  the 
235-foot  level  a  horizontal  diamond-drill  hole  (over  150  feet  in  length) 
was  bored  in  the  hanging,  but  no  other  parallel  ore-body  was  found. 
Cross-fissures,  from  3  to  6  inches  in  thickness,  are  met  with  in  the  mine, 
striking  1ST.  30°  to  35°  W.,  with  a  vertical  dip,  and  intersecting,  though 
not  faulting,  the  ore-bodies.  These  fissures  are  filled  with  coarse  crys- 
talline calcite,  sometimes  carrying  inconsiderable  amounts  of  pyrite. 
The  structure  of  the  vein-quartz  at  the  Franklin  is  banded,  and  its  char- 
acter is  milky,  glassy.  The  sulphurets  consist  mainly  of  coarse  crystal- 
line pyrite  (with  very  little  chalcopyrite),  usually  occurring  in  bunches. 
Although  the  ore  is  over  50  per  cent,  free-milling,  gold  visible  to  the 
eye  is  of  very  rare  occurrence.     The  fineness  of  the  gold  is  980  to  989. 

The  property  of  the  Creighton  Mining  and  Milling  Company  com- 
prises some  1800  acres.  The  first  work  done  here  was  by  open  cuts  in 
the  outcrop  of  the  ore-shoots.  After  the  death  of  Mr.  Franklin,  the 
original  owner,  the  mine  was  worked  for  a  long  time  by  his  widow. 

Before  the  adoption  of  the  chlorination  process  for  treatment  of  sul- 
phurets by  the  present  company,  a  cyanide  plant  was  erected  and  oper- 
ated for  a  short  time. 

The  present  condition  of  the  mine  is  shown  in  figure  20, 
giving  a  vertical  section  along  the  strike.  The  mine  is  worked  entirely 
through  No.  2  shaft  (1),  driven  in  the  hanging  wall  to  a  depth  of  215 
feet,  at  which  point  it  strikes  the  vein.  From  this  level  work  is  carried 
on  to  a  total  depth  of  430  feet  by  a  slope  on  the  dip  of  the  vein  and  the 
pitch  of  the  ore-shoot,  resting  on  a  small  horse  of  poor  ore. 

The  method  of  mining  the  ore  is  as  follows:  Levels  are  run  every 
100  feet,  and  the  ore-lenses  are  entirely  stoped  out,  leaving  the  inter- 
vening bodies  of  low-grade  material  as  pillars.  The  levels  are  con- 
nected by  a  series  of  raises,  their  number  depending  upon  the  length  of 
the  ore-shoots.  The  ore  is  then  stoped  by  underhand  work,  the  raises 
acting  as  ore-chutes  (mill-holes),  and  the  cars  being  loaded  directly  from 
pockets  in  the  level  below.  No  pillars  are  left  below  the  levels,  the 
track,  when  necessary,  being  carried  over  the  worked-out  stopes  on  stulls. 
Only  such  timbers  as  are  necessary  to  assist  the  men  in  their  work  are 
used,  the  walls  requiring  no  support.  All  the  material  stoped  is  hoisted 
and  milled,  leaving  no  waste  filling  in  the  mine.  Air-drills  are  used 
almost  exclusively;  for  stoping,  a  Baby  Band  with  J-inch  steel  is  used, 
while  drifting  is  clone  with  3|-inch  cylinder  Sergeant  machines.  The 
ore  is  raised  in  cars  of  -J-ton  capacity,  first  up  the  incline  by  underground 
hoisting  engine  (4),  and  then  trammed  to  the  bottom  of  the  vortical 
shaft,  from  where  they  are  hoisted  to  the  surface  on  cages.  Xo.  1  shaft 
(2)  is  used  for  ventilation  and  as  a  pipe-way.  The  mine  is  not  a  wet 
one,  a  small  steam-pump,  situated  immediately  below  Xo.  2  shaft,  taking 


124  GOLD    MINING    IN    GEORGIA. 

care  of  the  water.  At  the  surface,  the  ore  is  run  over  a  grizzly  and 
then  through  a  crusher,  the  jaws  of  which  are  set  1-J  inches  apart.  The 
crushed  ore  is  hauled  to  the  mill  by  mules  in  cars  of  1^  tons  capacity, 
which  are  loaded  from  a  bin  below  the  crusher. 

During  the  summer  and  fall  of  1895  two  other  shafts,  No.  3  and 
No.  4,  located  respectively  \  and  -§  miles  southwest  of  No.  2,  were  in 
progress  of  sinking,  with  the  object  of  developing  in  depth  lenses  of 
ore  which  had  been  located  and  worked  to  some  extent  on  the  surface. 
Considerable  diamond  drilling  has  been  done  on  the  property  (some  800 
feet  in  all)  at  a  cost  of  about  $1.25  per  foot. 

The  mill  is  situated  about.  J  of  a  mile  from  No.  2  shaft,  on  the  east 
bank  of  the  Etowah  river.  Water  at  a  head  of  7-J  feet  is  supplied  to  two 
turbine  wheels  by  a  dam  thrown  across  the  river.  One  of  the  turbines,  a 
60-inch  Leffel  wheel,  supplies  23  horse-power  to  the  stamp-mill,  while 
the  other,  a  56-inch  Davis  wheel,  drives  a  duplex  Rand  air-compressor. 
The  concentrators  are  run  by  steam-power,  that  derived  from  the  tur- 
bine not  being  of  sufficient  regularity  to  secure  a  uniform  product. 
There  are  20  stamps  in  the  mill,  10  of  Western  make  and  10  erected  by 
the  Mecklenburg  Iron  Works.  Weight  of  stamps  850  pounds,  7-inch 
drop,  70  drops  per  minute,  6-inch  discharge.  No  inside  plates  are  used 
and  no  quicksilver  is  fed  to  the  battery  (a  little  coarse  gold  is  cleaned 
from  the  battery  sands).  The  screens  are  No.  7  slotted  Russia  iron, 
corresponding  to  about  30-mesh.  The  outside  plates  have  the  full  width 
of  the  mortar.  They  are  8  feet  long,  arranged  in  four  steps,  and  are 
handled  in  the  same  manner  as  those  at  the  Haile  mine.  About  55  per 
cent,  of  the  gold  extracted  from  the  ore  is  saved  by  amalgamation.  The 
ore  is  fed  from  bins  by  Hendey  automatic  feeders.  The  mill  handles  35 
tons  in  twenty-four  hours. 

The  pulp  from  each  10  stamps  is  carried  by  launders  to  four  hydraulic 
classifiers,  the  overflow  from  all  these  going  to  one  slime-spitzkasten  of 
9  by  9  feet  surface  dimensions.  The  product  of  the  8  hydraulic  clas- 
sifiers goes  to  8  Embrey  tables,  the  product  of  the  slime-kasten  being  dis- 
tributed to  2,  making  10  tables  in  all  working  on  mill-pulp.  Besides 
these,  there  are  3  tables  working  on  old  amalgamation  tailings,  assaying 
about  $3  per  ton.  The  concentrates  are  not  clean,  containing  about  50 
per  cent,  of  sand,  but  close  work  would  decrease  the  percentage  of  ex- 
traction. The  average  amount  of  sulphurets  in  the  ore  mined  is  about 
5  per  cent.,  sometimes  running  as  high  as  9  per  cent.  As  high  as  5^ 
tons  of  raw  concentrates  are  produced  and  treated  in  twenty-four  hours. 
The  tailings  from  concentration  run  at  present  about  S5  cents  per  ton, 
giving  a  remarkably  high  percentage  of  extraction. 

The  concentrates  are  roasted  in  two  double-hearth  reverberatory  fur- 
naces, with  a  capacity  of  2  tons  of  roasted  ore  each  in  24  hours.     Twelve 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MIXES.        IZO 

pounds  of  salt  per  ton  are  added  to  the  charge  to  change  the  carbonate 
of  lime  present  to  chloride. 

Chlorination  of  the  roasted  concentrates  is  carried  on  in  a  one-barrel 
chlorination  plant,  the  arrangement  of  the  same  and  the  method  pur- 
sued being  identical  with  that  at  the  Haile  mine  (see  p.  137).  The  tail- 
ings from  the  chlorination  run  about  60  cents  per  ton,  giving  an  extrac- 
tion of  over  95  per  cent. 

Labor,  Costs,  etc. — At  the  time  of  our  examination  about  90  men 
were  on  the  pay-roll  of  the  company,  when  work  was  going  on  at  full 
capacity.  The  force  of  men  is  variable,  however,  depending  upon  the 
output  and  the  amount  of  development  work.  The  wages  paid  were  as 
follows : 

Per  day. 

Drill  runners $1.55 

Helpers 1.00 

Muckers 75  to  80  cents. 

Trammers    1.00 

Blacksmiths   2,25 

Carpenters  2.50 

Three  men  were  employed  on  each  12-hour  shift  in  the  mill  and  con- 
centration house  at  the  following  wages : 

Per  day. 

Amalgamator    .$1.40 

Concentrator 1.35 

Helper     75 

Boasting. — Two  men  on  each  shift,  at  $1.25.  Cost  of  roasting,  per 
ton  of  roasted  concentrates,  $2. 

Chlorination. — One  man  on  each  shift.  Cost  of  chloridizing  per  ton 
of  roasted  concentrates,  $1.48. 

Supplies. — Timber,  $9  per  1000  feet.  Cord  wood,  $1.25  per  cord, 
8  cords  used  per  day. 

Cost  per  ton  of  ore  mined: 

Mining,  crushing  and  tramming  to  mill $2.051 

Milling,  roasting  and  chlorination (J5 

Total    $2.70 

THE    HAILE    MINE,    LANCASTER    COUNTY,    S.    C.- 

The  Haile  mine  is  situated  3  miles  northeast  of  Kershaw  in  Lancaster 
county,  S.  C.  It  is  the  property  of  the  Haile  Gold  Mining  Company 
(New  York  office,  17  Maiden  Lane),  Capt.  A.  Thies,  superintendent  and 
general  manager. 

1  This  figure  includes  all  development  work.    The  average  value  of  the  ore  ami  the  concen- 
trates cannot  be  given  lor  private  business  reasons. 

2  Written  in  co-operation  with  Mr.  A.  Thies. 


126  GOLD    MINING    IN    SOUTH    CAROLINA. 

This  mine  represents  an  example  of  gold  mining  in  its  highest  devel- 
opment in  the  South,  on  large  bodies  of  low-grade  sulphuret  ore. 

It  is  situated  in  the  Carolina  belt.  '  The  country  is  a  siliceous  hydro- 
muscovite-  and  argillaceous-schist  striking  E".  45°  to  70°  E.  and  dipping 
55°  to  85°  N.W.  The  rock  is  impregnated  with  auriferous  pyrite,  free 
gold,  and  in  places  small  quartz-stringers.  This  is  the  mass  that  consti- 
tutes the  ore-bodies,  which  are  lenticular  in  shape.  Their  outline,  how- 
ever, does  not  necessarily  conform  with  the  strike  and  dip  of  the  slates,. 
but  is  determined  rather  by  the  degree  of  impregnation.  The  lenses  are 
about  200  feet  in  length  and  100  feet  in  maximum  width.  The  pitch  is 
50°  to  60°  N.E.,  and  the  dip  E~.W.  from  45°  to  nearly  vertical.  The 
country  is  intersected  by  a  number  of  diabase  dikes,  from  a  few  feet  to 
150  feet  in  width,  striking  across  the  slates  at  various  angles,  and  in  one 
instance  (Beguelin  mine)  parallel  with  them.  \Vhere  these  dikes  cross 
the  ore-bodies  they  appear  to  have  exerted,  in  some  cases,  an  enriching 
influence  on  the  ore.  A  short  distance  to  the  southeast  of  the  main 
workings  is  the  outcrop  of  a  heavy  quartz-vein  (F.,  fig.  21)  from  10  to 
12  feet  thick,  which  strikes  parallel  to  the  slates;  it  is  apparently  barren. 
As  explained  above,  the  ore  consists  of  pyritic  slates,  silicified  in  varying 
degrees,  from  soft,  sericitic  slate  to  very  hard  hornstone.  The  more 
siliceous  ores  are  usually  the  richest;  graphitic  laminae  are  also  good  indi- 
cations. In  the  better  grade  of  ore  the  pyrite  exists  in  a  finely  divided 
condition.  Ore  containing  coarse  sulphurets  is  generally  of  poor  grade. 
The  crucial  test,  however,  of  the  value  of  the  ore  is  the  amount  of  free 
gold  it  contains,  which  is  in  direct  proportion  to  that  contained  in  the 
sulphurets,  and  is  determined  by  daily  panning.  The  ore  at  present 
delivered  to  the  mill  averages  $4  per  ton  (assay  value),  of  which  about 
one-third  is  free  gold.1  The  percentage  of  sulphurets  in  the  ores  varies 
from  2  to  25  per  cent. 

The  first  work  done  at  the  Haile  mine  consisted  of  branch  washing 
in  1829,  which  led  afterwards  to  the  discovery  of  gold  on  the  hillsides. 
All  work  was  open  cutting  until  1880,  when  underground  mining  was 
begun,  and  this  is  continued  to  the  present  time.  Although  visible  coarse 
gold  is  now  of  rare  occurrence,  the  mine  has  yielded  some  nuggets  worth 
from  $300  to  $500  from  the  decomposed  slates  in  the  shallow  open  cuts/ 

The  first  mill  was  a  5-stamp  one,  afterwards  enlarged  to  10,  and  in 
1881  to  20.  About  1884  a  Blake  dry-crushing  mill  was  erected  in  con- 
nection with  20  Embrey  tables.3  This  was  soon  abandoned,  and  the 
mine  was  worked  in  a  dilatory  way  with  the  20-stamp  mill  until  1S88. 

1  Ores  as  low  as  $2.75  have  been  successfully  milled. 

2  First  Annual  Report  on  the  Survey  of  South  Carolina  for  1856,  by  O.  M.  Lieber,  Columbia,  S_ 
C,  1858,  p.  63. 

3  "The  Rlake  System  of  Fine  Crushing  and  Its  Economic  Results,1''  by  T.  A.  Blake,  Trans. 
Am.  Inst.  Min.  Eny.,  xvi,  753. 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MINES.        127 


Fig.  21. — Mines  and  Plant,  Haile  Gold  Mining  Co.,  Lancaster  County,  S.  C.  Scale,  I 
inch=400  feet. 

A,  Red  Hill  pits;  B,  Diabase  dikes;  C,  clay  dikes;  D,  outlet  of  large  reservoir  ;  E,  Bumalo  pit ; 
F,  quartz-vein;  G,  Beguelin  mine;  H,  Haile  pit;  K,  small  reservoir;  L,  Chase  Hill  pits;  L, 
chlorination  house;  2,  roasting  furnaces;  3,  boiler  house;  4,  pump;  5,  machine  shop;  <*>, 
No.  2  shaft ;  7,  new  shaft;  8,  No.  3  shaft;  9,  offices;  10,  superintendent's  residence;  11, 
mill;  12,  concentration  house;  13,  boiler  and  engine;  14,  crusher;  15,  new  Beguelin  shaft  ; 
16,  Beguelin  slope ;  17,  boiler  house;  18,  crusher;  19,  flume;  20,  mine  railroad;  21,  com- 
missary ;   22,  church  ;   23,  school ;   24,  village. 


I 


128 


GOLD    MINING    IN    SOUTH    CAROLINA. 


Plan, 


// 


Fig.  22.—  Beguelin  Mine  (part  of  the  Haile  Gold  Mine).  Scale  1  inch  — SO  feet 
D,  diabase  dikes;  S,  slate;  O,  ore-body;  1,  new  shaft;  2,  pillar;  3,  pit,  160  feet  deep:  4. 
inclined  shaft;  5,  crusher  and  ore-bin;  6,  mine  railroad;  7,  22-inch  diabase  dike;  8. 
diabase  dike,  parallel  to  ore-body  ;  9,  old  shaft,  50  feet  deep  ;  10,  open  cut,  40  feet  deep. 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MINES.        129 

During  this  time,  and  previously,  many  unsuccessful  experiments  for  the 
treatment  of  sulpliurets  were  made.1  In  1888,  Mr.  A.  Tliies  took  charge 
of  the  Haile  mine.  He  operated  the  20-stamp  mill  until  the  mine  was 
sufficiently  developed  to  warrant  a  larger  plant.  At  this  time  a  2-barrel 
ehlorination  plant  was  added  and  increased  later  on  to  3  barrels.  In 
1889  the  Blake  mill  was  changed  to  a  60-stamp,  back-to-back  mill,  with 
20  concentrators. 


The  present  workings  consist  of  the  Cross  (a  continuation  in  depth  of 
the  old  Haile  and  Flint  pits,  H,  fig.  21),  and  the  Beguelin  (G,  fig.  21) 
mines.  The  Bumalo,  Ked  Hill  and  Chase  Hill  pits  (E,  A  and  L, 
fig.  21)  have  not  been  worked  for  some  time,  although  in  the  first  there 
has  been  considerable  underground  work. 

Work  at  the  Cross  mine  Avas  stopped  in  1888,  and  all  attention  was 
concentrated  on  the  Beguelin  (formerly  Blauvelt)  mine.  Pig.  22  gives 
a  plan  and  vertical  section  of  the  open  pits  and  some  of  the  underground 
workings  of  this  mine.  The  old  workings  consist  of  some  shallow  open 
pits  and  3  perpendicular  shafts,  one  70  feet  deep  in  ore,  one  54  feet 
deep  in  the  diabase  dike  (9,  fig.  22),  and  one  70  feet  deep  in  the  foot- 
wall  slates  on  the  southwest  side  of  the  dike  (not  shown).  The  first  of 
these  was  transformed,  from  a  depth  of  60  feet  downward,  into  an  in- 
clined shaft  (4,  fig.  22),  and  sunk  in  the  ore-body  to  a  depth  of  195  feet. 
This  shaft  was  rigged  with  a  self-dumping  skip,  crusher  and  ore-bin  situ- 
ated over  the  railroad  tracks  which  had  been  extended  to  the  mine.  At 
60  feet  a  drift  was  run  in  a  northeast  direction  until  the  diabase  dike  was 
reached.  Meanwhile  sinking  was  continued  in  the  shaft  to  120  feet. 
From  this  level  drifts  were  run  and  connections  were  made  with  the 
60-foot  level,  which  prepared  the  ground  between  them  for  stoping. 
At  ISO  feet  a  similar  drift  was  run  to  the  dike  and  connections  made 
with  the  upper  levels  in  such  a  manner  that  the  ore  from  the  60-foot 
would  fall  to  the  180-foot  level,  and  from  there  be  hoisted  to  the  sur- 
face. At  180  feet  a  drift  was  started  in  a  southwesterly  direction,  en- 
countering at  64  feet  a  dike  125  feet  thick,  through  which  the  drift  was 
continued  to  a  distance  of  600  feet  from  the  shaft.  At  a  depth  of  70 
feet  a  similar  drift  was  run  and  the  ore-body  beyond  the  dike  was  pre- 
pared for  stoping  by  connecting  these  two  drifts  by  several  raises.  At 
the  present  day  all  ore  on  the  west  side  of  the  dike  has  been  stoped  out 
to  the  180-foot  level.     To  the  northeast  of  the  shaft  a  considerable  body 

1  "Gold  Mining  in  South  Carolina,"  by  E.  G.  Spilsbury,  Trans.  .1///.  Inst.  Min.  Engs.,  xii,  99. 
"  Notes  on  the  General  Treatment  of  the  Southern  Gold  Ores  and  Experiments  in  Matting 
Iron  Sulphides,"  by  E.  G.  Spilsbury,  Ibid.,  xv,  767. 
"Chlorination  of  Gold  Bearing-  Sulphides,"  by  E.  G.  Spilsbury,  Ibid  ,  xvi,  359. 
9 


• 


130 


GOLD    MINING    IN    SOUTH    CAROLINA. 

^  ^         t 


Fig.  23.— Plan  of  Cross  Mine  (part  of  the  Haile  Gold  Mine).     Scale,   1  inch=100  feet. 

B,  Bumalo  pit ;  C,  clay  dike  ;  D,  diabase  dikes  ;  F,  Flint  pit ;  H,  Haile  pit ;  S,  old  stope  -00-foot 

level ;  «,  No.  2  shaft ;  6,  No.  3  shaft ;  c,  new  shaft ;  d,  bottom  of  old  stope,  160  feet,  rising  to  100 

feet :  e,  120-foot  level ;  /,  200-foot  level :  g  and  ht  270-foot  level ;  O.  ore-bodies  ;  1.  2,  3  #  stop! 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MINES.         161 

of  ore  was  still  standing  above  the  60-foot  level.  In  order  to  extract  this 
ore  it  became  necessary  to  open  the  mine  from  the  surface,  and  the  open 
pit  (3,  fig.  22)  was  started.  The  gronnd  was  stripped  to  a  depth  of  15 
feet,  and  from  that  point  on  the  ore,  though  lean,  was  used  in  the  mill. 
At  60  feet  a  diabase  dike  (8,  fig.  22),  lying  parallel  to  the  schistosity 
of  the  country,  was  encountered  in  cross-cutting  and  was  at  first  believed 
to  represent  the  hanging  wall.  On  cutting  through  it,  however  (a  dis- 
tance of  4  feet),  it  was  found  to  merely  divide  the  ore-body.  Under  the 
altered  conditions  it  became  necessary  to  sink  a  new  shaft  (1,  fig.  22) 
in  the  hanging  wall  as  an  outlet  for  the  ore  and  for  pumping.  This 
shaft  was  sunk  to  a  depth  of  165  feet;  connections  were  made  by  cross- 
cuts with  the  present  inclined  shaft  and  everything  prepared  for  taking 
out  the  shaft  pillars,  as  well  as  the  remainder  of  the  ore.  This  is  the 
present  condition  of  the  mine.  The  maximum  thickness  of  the  ore- 
body  at  the  Beguelin  was  80  feet,  and  the  best  ore  was  found  between 
the  two  large  cross-dikes.  A  large  amount  of  heavy  sulphuretted  ores 
is  at  present  in  sight. 

Five  hundred  feet  northeast  of  the  Beguelin  mine  are  several  open 
pits  known  as  the  Chase  Hill  (L,  fig.  21).  The  character  of  the  ore  at 
this  point  is  somewhat  different,  being  a  banded,  colored  slate,  barren  of 
sulphurets,  but  carrying  several  gold-bearing  quartz-veinlets.  Taken  as 
a  body  it  will  not  make  ore. 

To  the  northwest  of  the  Beguelin  are  several  ore-leads  as  yet  un- 
prospected. 

The  60-stamp  mill  was  run  on  Beguelin  ores  three  years.  The  Cross 
mine  was  then  reopened  (1891).  A  plan  of  the  Cross  mine  is  given  in 
fig.  23  showing  the  open  pits  and  present  underground  workings,  as 
well  as  some  of  the  abandoned  ones.  After  the  water  had  been  pumped 
out,  and  the  old  shaft  No.  2  (a,  fig.  23),  200  feet  deep,  was  fully 
secured,  a  cross-cut  was  driven  in  a  northwesterly  direction  from  the 
bottom,  a  distance  of  25  feet.  A  drift  (/,  fig.  23)  was  started  from 
that  point  in  a  south  westerly  direction,  reaching  ore  at  a  distance  of  75 
feet  from  the  cross-cut.  This  drift,  on  being  continued  200  feet,  en- 
countered a  dike  25  feet  thick,  which  was  cut  through  and  the  drift  car- 
ried on  for  100  feet  more.  The  old  workings  (d,  fig.  23)  were  also  con- 
tinued through  the  dike,  the  drift  (e,  fig.  23)  on  the  100-foot  level  being 
run  100  feet  beyond  it.  Four  upraises  were  driven  between  these  two 
levels,  two  on  each  side  of  the  dike,  opening  up  4  large  stopes  of  ore. 
This  ore  ran  low  in  sulphurets,  but  carried  more  free  gold  and  furnished 
one-half  of  the  quota  to  the  mill.  In  order  to  work  the  ores  below  the 
200-foot  level  a  new  shaft  (c,  fig.  23)  was  sunk  to  a  depth  of  270  feet. 
A  cross-cut  was  run  from  the  bottom  in  a  southwesterly  direction  for  a 
distance  of  75  feet;  15  feet  from  the  shaft  a  drift  (li,  fig.  23),  parallel  to 


132  GOLD    MINING    IN    SOUTH    CAROLINA. 

the  drift  (/)  on  the  200-foot  level,  was  carried  in  a  distance  of  250  feet. 
The  dike  when  encountered  was  35  feet  thick  and  no  longer  decomposed 
on  the  wall,  as  was  the  case  in  the  npper  level,  but  hard  and  solid.  By 
upraises  4  more  stopes  were  opened.  The  ore  was  of  a  better  grade  in 
proximity  to  the  dike  on  both  sides. 

During  1896  an  open-cut  was  made  opposite  the  old  Haile  pit,  in 
order  to  take  out  the  pillars  and  the  ore  in  the  hanging,  above  the  200- 
foot  level. 

The  old  workings  (S,  fig.  23),  which  were  continued  from  the  Bu- 
malo  pit  (B,  fig.  23),  to  a  depth  of  200  feet,  and  were  for  a  long  time 
inaccessible,  have  been  opened  up  by  a  diagonal  drift  from  the  270-foot 
level  (h,  fig.  23).  Some  time  ago  a  northeast  tunnel  was  driven  from 
the  Bumalo  pit,  at  a  depth  of  50  feet  and  for  a  distance  of  150  feet,  to 
a  diabase  dike  150  feet  in  thickness,  and  later  continued  through  this. 
Drifts  on  the  further  side  showed  up  only  barren  ground,  but  good  ore 
was  found  from  the  mouth  of  the  tunnel  to  the  dike,  being  richest  near 
the  dike.  This  ore-body  was  encountered  in  the  270-foot  level  with 
the  drift  above  mentioned,  and  the  ores  are  found  to  be  more  heavily 
sulphuretted  than  anywhere  in  the  Cross  mine. 

So  far  as  explorations  have  gone,  3  different  lenses  have  been  encoun- 
tered: 1.  The  Bumalo,  furthest  northeast;  2.  The  Haile  or  middle  lens: 
3.  A  small  lens  80  to  90  feet  west  of  the  Haile  (outcrop  under  the  new 
boiler-house,  17,  fig.  21). 

During  the  summer  of  1896  an  electric  diamond-drill  hole  was  started 
in  back  of  the  old  store  building  (just  to  the  right  of  5,  Rg.  21).  At 
a  depth  of  58  feet  the  cores  showed  ore,  assaying  as  high  as  $6,  and  it 
appears  as  though  this  were  in  a  new  hanging  wall  lens.  In  order  to 
solve  this  question  a  cross-cut  is  being  driven  on  the  270-foot  level  along 
the  25-foot  dike  in  a  northwesterly  direction. 

Bed  Hill  (A,  fig.  21)  consists  of  a  number  of  open  pits  on  the  north- 
west side  of  the  150-foot  dike,  where  ore  was  formerly  mined  to  a  depth 
of  60  feet.     It  is  supposed  to  be  in  a  line  with  the  Haile  lens. 

The  thickness  of  these  lenses  varies,  reaching  100  feet  in  places,  while 
at  others,  near  the  end  of  the  lenses,  it  is  only  from  25  to  30  feet. 

METHOD    OF    WORKING;    HAILE    MINE. 

The  method  of  working  these  deposits  is  the  pillar  system  (Pfeilerbaif). 
illustrated  in  fig.  24. 

The  levels  (8x7  feet)  are  run  70  to  100  feet  apart,  and  nearer  the 
hanging  than  the  foot-wall.  At  intervals  of  about  50  feet  upraises  are 
made,  with  a  cross-section  of  Sx7  feet.  These  are  carried  forward  at 
an  inclination  as  near  as  possible  to  45°.  If  necessary,  the  upper  portion 
through  the  chain  pillar  left  under  each  level  is  carried  up  vertically. 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MINES. 


133 


This  raise  serves  afterwards  as  a  chute  (mill-hole).  Drifts  are  then  run 
below  this  pillar  until  the  limit  of  the  stope  in  length  (about  30  to  40 
feet  in  all)  is  reached,  leaving  a  vertical  pillar  15  to  20  feet  in  thickness 
between  the  stopes.  The  ground  is  then  cut  away  between  the  foot-  and 
hanging  walls,  completely  exposing  as  roof  the  bottom  of  the  chain  pillar 
above,  which  is  sprung  in  the  shape  of  an  arch,  with  its  heavier  toe  in 
the  foot-wall  and  a  minimum  thickness  of  15  feet.  This,  as  well  as 
all  other  work  in  tight  ground,  is  done  by  air-drills.  Stoping  is  then 
carried  downward  by  hand-drilling  in  circular  steps,  arranged  in  such  a 
manner  as  to  allow  the  broken  ore  to  drop  into  the  chute,  without  further 
handling.     The  angle  of  45°  given  to  the  latter  allows  a  steady  flow  of 


Vertical  Section  along  Strike.  Section  on  X-Y. 

Fig.  34.— Method  of  Stoping  at  the  Cross  Mine  (Halle  Mine).     Scale,  1  inch=60feet. 

the  material  down  the  foot-wall  without  completely  choking  it.  At  the 
bottom  of  the  chute  is  a  rough  grizzly  (a,  fig.  24)  made  of  logs,  which 
holds  back  the  larger  boulders  and  prevents  them  from  choking  the 
smaller  loading  pocket  below.  This  grizzly  is  easily  accessible  from  the 
drift,  and  the  larger. pieces  of  ore  are  here  sledged.  The  loading-chute 
and  grizzly  are  kept  up  as  long  as  possible,  until  the  stope  is  finally 
broken  through  to  the  drift-level  below,  the  ore  being  shoveled  into 
cars.  As  far  as  possible,  the  pillars  are  left  in  poor  ore,  the  diabase  dike 
fulfilling  this  purpose  admirably.  ~No  timber  whatever  is  used,  and 
although  chambers  100  by  100  by  40  feet  have  been  cut  out,  there 
seems  to  be  no  danger  of  a  fall,  the  country-slate  being  very  tough  and 
self-supporting.  The  stopes  from  the  100-  and  200-foot  levels  are  con- 
nected with  the  surface  by  raises,  so  that  at  a  future  date  the  worked-out 


134 


GOLD    MINING    IN    SOUTH    CAROLINA. 


at     S 


— Y 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MINES.        135 

stopes  can  be  filled  from  the  surface  and  the  ore  in  the  pillars,  i.  e.,  what 
is  left  toward  the  hanging  wall,  can  be  taken  out. 

Blasting  is  done  with  40  per  cent.  Hercules  powder.  One-inch  steel 
is  used  for  both  hand  and  machine-work.  The  number  of  air-drills  is 
limited  by  the  size  of  the  compressor — an  Ingersoll  machine,  with 
3-drill  capacity.  The  ore  is  carried  from  the  loading-chutes  to  the  shafts 
in  sheet-iron  cars  of  f-ton  capacity,  running  on  18-inch  gauge  track. 
At  No.  2  Shaft  (7x12  feet,  single  compartment)  they  are  hoisted  by 
cage,  with  automatic  safety  catch.  The  new  shaft  is  6x14  feet,  double 
compartment,  and  the  ore  is  raised  by  a  novel  skip  designed  by  Mr. 
Thies  (fig.  25).  The  body  of  the  skip,  made  of  sheet  iron,  has  two 
projecting  lugs  riveted  to  it  below  the  centre  of  gravity  and  the  bail  is 
lugged  one  inch  from  the  vertical  centre  line. 

Each  lug  runs  between  a  pair  of  yellow-pine  guides  set  2  inches  apart. 
When  the  skip  is  raised  above  the  landing-chute  two  iron  pins  are 
thrown  across  the  openings  between  each  set  of  guides.  The  skip  is 
dropped  down  on  these  and  the  ore  is  dumped  into  a  loading-chute 
placed  on  the  heavier  side  of  the  skip.  The  skip  is  raised  and  righted 
by  the  bail,  the  iron  pins  are  withdrawn  by  the  lander,  and  the  skip  de- 
scends. The  operation  is  rapid  and  simple  and  the  cost  of  the  device  is 
light.  The  mine  is  not  wet,  a  No.  9  Cameron  pump  easily  handling  the 
water. 

MILLING    AND    ORE    TREATMENT    AT    THE    HAILE    MINE. 

The  ore  is  crushed  to  1^-inch  size  in  a  10x2  0-inch  Blake  crusher  at  the 
Beguelin,  and  a  7x1 0-inch  crusher  at  the  Cross  mine,  and  is  stored  at 
both  places  in  bins  of  30  tons  capacity.  The  broken  ore  is  hauled  to  the 
mill  in  narrow-gauge,  bottom-dumping  cars,  holding  3  tons;  8  cars  are 
run  to  the  trip.  The  mill  bin  has  a  capacity  of  300  tons,  and  is  so 
arranged  that  every  stamp  can  be  supplied  separately  with  ore,  as,  owing 
to  the  different  character  of  the  ore  at  the  Beguelin  and  the  Haile,  it  is 
treated  in  separate  batteries.  A  hinged  plate,  not  shown  in  the  accom- 
panying illustration,  is  for  this  purpose  hung  at  the  apex  of  the  bin 
floor.  A  vertical  cross-section  of  the  mill  is  shown  in  fig.  26.  Two  ver- 
tical sections  of  a  similar  battery  at  the  Reimer  mine  are  shown  in  fig. 
19  (p.  120). 

The  mill  is  a  60-stamp  back-to-back  one,  30  on  each  side,  built  by  the 
Mecklenburg  Iron  Works  of  Charlotte,  N.  C.  The  ore  is  fed  by  Hendey 
self-feeders.  The  weight  of  the  stamps  is  750  pounds;  chilled  iron 
shoes  and  dies  are  used;  the  stamps  drop  6  inches,  86  times  per  minute, 
in  the  order  1,  3,  2,  5,  4.  The  crushing  capacity  is  2  tons  to  the  stamp 
in  24  hours.  The  screens  are  30-mesh,  made  of  No.  20  brass  wire:  these 
work  well  if  no  cyanide  is  used  in  the  battery.     The  average  height  of 


136 


GOLD    MIXIXG    IX    SOUTH    CAROLINA. 


discharge  is  6  inches.  Amalgamation  is  accomplished:  (1)  In  the  mortar 
by  a  curved  front  plate  attached  by  means  of  a  wooden  chuck-block  to 
the  lip  of  the  mortar,  immediately  below  the  discharge ;  it  is  held  in  posi- 
tion by  bolts  and  can  be  rapidly  and  easily  removed.  It  present-  an 
amalgamation-surface  of  1.75  square  feet  and  is  made  of  Xo.  7  silver- 
plated  sheet-copper.  The  gold  being  very  fine,  its  accumulation  in  the 
mortar  between  the  dies  is  insignificant,  and  the  mortar  is  seldom  cleaned 


Fig.  26. — Vertical  Cross-section  of  60-starnp  Mill  at  the  Haile  Gold  Mine. 

out.  (2)  On  the  outside  plates,  made  of  Xo.  12  silvered  copper-sheet,  and 
presenting  an  amalgamation-surface  of  32  square  feet  to  each  battery  of 
5  stamps;  they  are  the  full  width  of  the  mortar  and  are  arranged  in  four 
steps,  each  2  feet  in  length,  and  overlapping  the  next  by  1  inch,  the 
inclination  being  2  inches  in  1  foot.  They  are  fastened  directly  to  the 
battery,  the  tremor  caused  hereby  being  considered  beneficial  to  amal- 


TREATMEXT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MIXES.        137 

gamation.  These  plates  are  interchangeable;  whenever  the  upper  plate 
becomes  hard  and  unfit  for  amalgamation,  it  is  interchanged  with  one  of 
the  lower  plates,  thus  giving  in  rotation  to  each  plate  a  position  at  the 
head  of  the  table.  The  outside  amalgamation-surface  of  each  battery  is 
further  increased  by  12  additional  square  feet,  arranged  by  a  drop  system 
of  three  plates,  the  pulp  discharging  from  one  to  the  other  before  it 
enters  the  main  launder.  Each  battery  is  provided  at  the  screen-dis- 
charge with  an  impact-plate,  not  only  for  amalgamation,  but  to  retard 
the  velocity  of  the  pulp.  They  are  cleaned  from  verdigris  with  a  weak 
solution  of  cyanide,  and  a  little  potash  is  sometimes  fed  into  the  battery. 
Phosphate  of  sodium  is  used  in  the  mill  to  keep  the  quicksilver  bright 
and  lively.  It  has  been  found  expedient  to  remove  the  inside  plates 
every  24  hours;  as  duplicate  plates  are  kept  on  hand,  no  delay  occurs 
while  they  are  being  cleaned.  The  amalgam  from  these,  which  is  col- 
lected and  weighed  daily,  forms  an  excellent  indication  of  the  value  of 
the  ore  milled.  The  amalgam  is  removed  from  the  outside  plates  when- 
ever it  is  necessary.  A  regular  clean-up  is  made  only  once  a  month. 
About  one-third  of  the  gold  is  saved  on  the  inside  plates.  The  fineness 
of  the  mill  gold  is  880.  The  average  amount  of  water  used  per  stamp 
is  3-J  gallons  a  minute;  and  the  average  consumption  of  quicksilver  is 
0.35  ounce  per  ton  of  ore.  The  wear  of  shoes  and  dies  is  1.3  pounds 
per  ton  of  ore  stamped.  As  a  lubricant  for  the  cams,  molasses  thickened 
with  flour  is  used  and  gives  excellent  results. 

The  pulp  is  carried  to  the  concentrators  in  launders  lined  with  riffles 
for  a  distance  of  eighty  feet.  JSTo  attempt  at  sizing  the  pulp  is  made, 
but  the  ores  from  the  Beguelin  and  Cross  mines,  owing  to  the  differ- 
ence in  contents  of  sulphurets,  are  concentrated  separately.  The  Cross 
ore  averages  about  2  per  cent.,  the  Beguelin  running  from  about  7  to 
25  per  cent,  sulphurets.  They  are  milled  separately  in  the  proportion  of 
xV  Beguelin  and  xV  Cross,  so  as  to  obtain  an  average  of  7  to  8  per  cent, 
sulphurets  from  the  total  ore  milled.  The  concentration  is  done  on  20 
Embrey  tables  (4  by  12  feet),  with  smooth  rubber  belts  which  are  set 
at  an  inclination  of  2f  inches  and  travel  5  feet  per  minute,  receiving  at 
the  same  time  192  percussions.  The  concentrates  contain  90  per  cent. 
pyrite,  which  is  pure  sulphide  of  iron  with  occasional  small  traces  of 
arsenic.  The  loss  in  concentration  is  15  to  20  per  cent.  The  averag< 
value  of  these  concentrates  is  $25  to  $35  per  ton. 

Chlorination. — The  concentrates  are  hauled  on  the  mine-railway  to 
the  chlorination  plant.  They  are  roasted  in  two  double-hearth  rever- 
beratory  (see  fig.  27)  and  one  revolving  pan-furnace,  the  sulphur  being- 
reduced  from  about  43  to  as  low  as  -J  per  cent.,  and  the  value  of  the 
material  being  increased  by  -J.  Each  double-hearth  furnace  is  worked 
by  two  men  to  a  shift  of  12  hours,  the  output  being  2  ton-  of  roasted 


138 


GOLD    MINING    IN    SOUTH    CAROLINA. 


«^R 


P^5£3 


Irf 


#-+ 


if  I 


H*   § 


:i 


TREATMENT    OF    SULPIIURET    ORES    AT    CHARACTERISTIC    MINES. 


139 


concentrates  per  24  hours  for  each  furnace.  The  revolving  pan-furnace 
is  worked  by  three  men  per  24  hours,  with  the  same  output  as  the  double- 
hearth.  The  fumes  from  these  furnaces  carry  off  into  the  air  the  equiv- 
alent of  13  tons  of  50  per  cent,  sulphuric  acid.  The  management  has 
investigated  the  erection  of  lead  chambers,  but  so  far  have  not  consid- 
ered such  an  installation  to  their  advantage.     The  Spence  furnace  has 


Fig-.  28. — Cliloriuation  plant  at  the  Haile  Gold  Mine.     Vertical  Longitudinal  Section. 

been  tried  at  the  Haile,  without  success.1  The  roasted  ore  after  cooling 
is  elevated  to  the  top  floor  of  the  chlorination  house,  82  feet  high.  This 
consists  of  a  four-story  frame  building,  containing  3  chlorination-barrels, 
11  filtering-tanks,  2  storage-tanks,  and  13  precipitating  vats  (see  figs. 
28,  29).     The  ore  is  charged  through  a  hopper  into  the  chlorination- 

lSee  paper  by  A.  Thies  and  W.  B.  Phillips,  "The  Thies  Process  of  Treating  Low-grade 
Auriferous  Sulphides  at  the  Haile  Gold  Mine,  Lancaster  Co.,  S.  C,"  Trans.  Am.  Inst.  Mill.  Eng., 
xix,  601. 


■HM 


. 


140 


GOLD    MINING    IN    SOUTH    CAROLINA. 


barrels  (see  fig.  30)  by  cars  holding  1  ton  each.  The  barrel  is  60  inches 
long  by  42  inches  in  diameter,  made  of  cast-iron  and  lead-lined  (12 
pounds  of  lead  to  the  square  foot).  It  also  contains  a  lead  valve  in 
order  to  ascertain  whether  the  necessary  amount  of  free  chlorine  is 
present.  (The  use  of  this  valve  is  unnecessary  after  the  character  of 
the  ores  becomes  known). 


Fig.  29. — Chlorination  Plant  at  the  Haile  Gold  Mine.     Vertical  Cross-section. 

The  full  charge  consists  of  120  gallons  of  water  (to  make  an  easily 
flowing  pulp),  from  8  to  11  pounds  of  bleaching  powder,  then  the  ore, 
and  finally  12  to  15  pounds  of  sulphuric  acid.  The  barrel  is  hermeti- 
cally closed  and  revolves  for  about  3  hours  at  the  rate  of  15  to  IS  revolu- 
tions per  minute.  (A  5  horse-power  engine  performs  this  work  and 
also  the  elevating  of  the  ore.)  The  barrel  is  then  inverted,  opened  and 
discharged  through  a  lead-lined  semicircle  in  the  floor  to  a  filter  on  the 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MIXES.        141 


Fig.  30.— Chlorination-Barrel,  Haile  Gold  Mine.  The  upper  Bgure  is  a  vertical  cross- 
section,  and  the  lower  a  vertical  longitudinal  section.  Inside  dimensions:  Diameter, 
42  inches  ;  length,  60  inches. 


142  GOLD    MINING    IN    SOUTH    CAEOLIXA. 

floor  below.  There  are  4  lead-lined  filters  to  each  barrel,  their 
sizes  being  6  by  8  feet  by  18  inches  deep  in  front  and  17  inches  in  back. 
The  bottom  is  covered  with  mineraline  1  tiles  12  by  12  inches  by  1  inch 
thick,  perforated  and  having  -J-inch  gutters  underneath;  on  top  of  these 
is  placed  a  rack  of  lj-inch  wooden  slats,  4  inches  high  and  8  inches 
apart;  the  first  layer  above  the  tiles  consists  of  4  inches  of  coarse  quartz 
pebbles  (-§•  to  -J  inch  size),  and  this  is  covered  by  from  1  to  2  inches  of 
ordinary  clean  sand.  Before  emptying  the  contents  of  the  barrel,  the 
filter  is  flooded  with  water  to  the  level  of  the  top  of  the  filter-bed  to  act 
as  a  cushion.  Then  the  original  solution  is  passed  through,  striking  on 
a  float  to  prevent  breaking  the  filter-bed.  The  ore-pulp  is  washed  twice 
with  clean  water;  the  first  time  enough  is  added  to  stand  4  inches  above 
the  surface  of  the  pulp,  and  the  second  time  the  tank  is  entirely  filled. 
This  amount  is  found  sufficient  to  thoroughly  remove  all  traces 
of  chloride  of  gold  from  the  pulp  (tests  are  made  with  TeSOj.  The 
filtered  solutions  are  stored  in  two  stock-tanks  on  the  second  floor,  and 
are  drawn  off  from  these  into  the  precipitating-tanks  as  required.  The 
latter  are  S  feet  in  diameter  and  3  feet  high,  made  of  wood,  the  interior 
coated  with  asphalt.  They  are  provided  with  three  outlets,  the  upper 
one  IS  inches  from  the  top,  the  middle  one  1  inch  above  the  bottom  and 
the  lowest  one  in  the  jamb.  The  gold  is  precipitated  in  the  metallic  state 
with  an  excess  of  fresh  ferrous  sulphate,  made  in  a  small  lead-lined  tank. 
Tn  warmer  weather  48  hours  suffice  for  settling,  and  in  colder  weather 
from  3  to  4  days.  The  supernatant  liquor  is  drawn  off  through  the  two 
upper  outlets,  opened  one  after  the  other  (in  order  to  prevent  auy  stir- 
ring of  the  precipitates),  and  passed  through  a  box  filled  with  sawdust 
to  catch  any  precipitate.  The  gold  precipitate  is  drawn  from  the  tanks 
through  the  jamb-opening  into  a  small  lead-lined  settling-tank  2  by  2  by 
4  feet.  After  standing  24  hours  the  supernatant  liquor  is  siphoned  off, 
and  the  precipitate  filtered  on  paper.  This  is  dried  and  mixed  with 
about  half  its  weight  of  borax  and  soda  in  almost  equal  proportions. 
Should  iron  salts  be  present,  a  little  quartz  sand  is  added.  It  is  melted 
in  graphite  crucibles  and  cast  into  ingots  of  about  990  fineness.  The 
whole  operation  is  so  simple  that  the  most  ordinary  laborer  can  acquire 
the  mechanical  knowledge  in  a  day.     The  repairs  are  practically  nil.3 

LABOE,   COSTS,   ETC.,   AT  THE  HAILE   MINE. 

Some  of  the  figures  of  costs  of  labor  and  working  at  the  Haile  mine 
are  given  below.  For  private  business  reasons  it  is  impossible  to  give 
these  as  fully  as  we  should  like  to. 

1  A  melted  mixture  of  sulphur  and  quartz. 

2  The  Thies  chlorination  process  has  been  described'in  detail  by  T.  K.  Rose,  in  his  Metallurgy 
of  Gold,  C.  Griffin  &  Co.,  London,  1894. 


.' 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MINES.         143 

Mines. — Cost  of  Labor: 

Per  day. 

Holders    $  .90 

Strikers   1.10 

Machine-runners    1.25 

255  cords  of  wood  at  $1.50,  burned  per  month. 

Mill  (2  shifts  of  12  hours  each).— Distribution  and  Cost  of  Labor: 

One  superintendent  $ 

"     laborer  (amalgamation)  per  shift 2.50 

1.00 

(concentration)         "  1.25 

SO 

"     fireman  per  shift ., 1.00 

"     engineer  per  day  shift  1.75 

"  per  night  shift  1.50 

150  cords  of  wood  at  $1.50,  used  per  month. 
Repairs  (wear  of  shoes  and  dies,  etc.),  4  cents  per  ton  of  ore. 

Roasting  and  Chlorination.— Distribution  and  Cost  of  Labor: 
Roasting  furnaces,  producing  6  tons  of  roasted  concentrates 

per  24  hours;  six  men,  day  shift,  each $1.00 

Five  men,  night  shift,  each 1.00 

3  cords  of  wood  at  $1.50.  used  per  24  hours. 

Chlorination  (1  shift  of  12  hours)  working  6  tons  of  roasted  concentrates: 

Two  men,  each  at  $1.00 

One  man  at 1.25 

Cost  of  roasting  per  ton  of  roasted  concentrates: 

Labor  $1.83 

Fuel 75 

$2.58 
Cost  of  chlorinating  1  ton  of  roasted  concentrates: 

Labor  $  .50 

Foreman 20 

Power   12 

Sulphuric  acid  for  FeSo4 06 

11  pounds  of  bleaching  powder,  at  iy2  cents 27% 

15  pounds  of  sulphuric  acid,  at  1  cent 15 

Wear  and  tear 10 

Superintendence   05 

$1.45Vo 

Cost  of  roasting  and  chlorination  per  ton  of  raw  concentrates.  .$3.02 
Cost  of  roasting  and  chlorination  per  ton  of  ore  mined 19 

Percentage  of  Extraction: 

Mill:   Tailings  from  concentrators 85  to  90  cents. 

Showing  a  yield  of  75  to  80  per  cent. 

Chlorination:    Tailings  as  high  as  $1.50 

Average  yield   94  per  cent. 


141-  GOLD    MINING    IN    SOUTH    CAROLINA. 

THE  BREWEE  MINE,   CHESTERFIELD  COUNTY,   S.   C. 

The  Brewer  mine  (the  De  Soto  Mining  Company)  is  situated  on 
Lynch's  creek,  about  13  miles  by  road  northeast  of  Kershaw,  the  nearest 
railroad  station;  it  is  about  8  miles  (air-line)  northeast  of  the  Haile  mine. 

The  mining  problem  presented  here  is  the  working  of  large  bodies  of 
low-grade,  sulphuretted  ores  by  quarrying,  milling,  concentration,  and 
chlorination. 

Geologically,  the  mine  is  situated  in  the  Carolina  belt.  The  country- 
rock  is  a  hard,  de  vitrified  acid  volcanic  (probably  quartz-porphyry ) .  of 
a  light  bluish-gray  color,  resembling  hornstone  or  chert.  It  is  in  part 
sheared  into  sericitic  schists,  similar  to  the  slates  at  the  Haile  mine, 
though  more  highly  silicified.  Masses  of  coarse,  pyroclastic  breccia 
were  found  in  the  bottom  of  the  large  mine-pit,  but  the  rock  was  not 
observed  in  place.  The  strike  of  the  siliceous  schists  is  very  much  con- 
fused, being  in  all  directions;  the  normal  strike  is  probably  something 
like  !N".  70°  E.,  and  the  dip  60°  "N.~W:  [Numerous  coarse-grained  granitic 
dikes  (Gr,  fig.  31)  intersect  the  country,  and  the  local  abnormal  strikes 
and  dips  of  the  schists  may  be  due  to  their  intrusion.  These  rocks 
occupy  an  elevation  known  as  Brewer  hill,  which  rises  some  200  feet 
above  the  level  of  the  main  drainage  basin,  Lynch's  creek  on  the  east 
and  Flat  creek  on  the  west.  A  heavy  diabase  dike  lies  on  the  west  bank 
of  Flat  creek,  and  to  the  west  of  that,  the  country-rock  is  granite. 

The  ore-bodies  at  the  Brewer  are  similar  to  those  of  the  Haile  mine, 
being  auriferous  pyritic  impregnations  in  the  country-rock,  and  assum- 
ing more  or  less  lenticular  forms.  Free  gold  appears  as  thin  films  or 
coatings  on  the  cleavage-  and  joint-planes  of  the  schists.  The  ore-bearing 
rock  is  decomposed,  in  certain  streaks  more  than  in  others,  to  the  deepest 
workings  of  the  mine,  150  feet,  resulting  in  soft,  friable  masses  which 
disintegrate  into  finely  divided  white  sand.  Certain  portions  of  the 
deposit  are  richer  in  gold,  and  these  also  have  an  imperfect  lenticular 
shape,  from  10  to  30  feet  in  thickness  (O,  fig.  31).  These  better 
grade  ores  will  run  from  $5  to  $7  per  ton,  assay  value,  while  the  average 
run  of  the  mine  is  in  the  vicinity  of  $3.  The  fineness  of  the  gold  is  from 
070  to  984.  The  total  width  of  the  ore-bearing  ground  is  stated  to  be 
800  yards.  The  main  ore-body  has  been  opened  for  a  distance  of  600 
feet  in  a  north  and  south,  and  250  feet  in  an  east  and  west  direction. 
The  sulphuret  contained  in  the  ore  (finely  divided  pyrite)  averages 
about  7  per  cent  of  the  total  mass.  In  one  portion  of  the  mine 
enargite  (and  perhaps  also  covellite)  appears  in  some  quantity,  but  its 
occurrence  is  local.  Other  sulphurets  occur  in  small  quantities,  but  are 
interesting  merely  from  a  mineralogical  standpoint.  Tinstone  (some- 
times in  direct  association  with  gold)  has  been  found  in  hydraulicking 


TREATMENT    OF    SULPHTJRET    ORES    AT    CHARACTERISTIC    MIXES.        145 

at  the  Tan-yard  deposit;  and  pyrophyllite  occurs  as  an  alteration  pro- 
duct in  the  granitic  dikes. 

The  ore  itself  is  practically  devoid  of  auriferous  vein-quartz.  Small 
reticulated  fissures  filled  with  barren  quartz  intersect  the  country;  and 
in  the  Tan-yard  (an  old  gravel-channel  to  the  east  of  the  mine)  a  large 
barren  quartz-vein,  5  to  20  feet  in  thickness,  is  to  be  seen. 

The  Brewer  mine,  probably  one  of  the  first  developed  in  South  Caro- 
lina, was  opened  in  1828  by  shallow  pits  in  the  saprolites  and  in  the 
gravels  of  the  Tan-yard,  the  material  being  worked  in  rockers.  This 
work  continued  until  1857,  and  it  is  stated  that  in  various  years  during 
this  period  as  many  as  100  to  200  hands  were  employed  at  one  time,  mak- 
ing $1.50  to  $3  per  day  each,  and  paying  nearly  30  per  cent,  royalty. 
From  1857  to  1862  Commodore  Stockton  mined  and  milled  the  ore  in 
arrastras  and  Chilian  mills.  Up  to  1879,  when  the  Brewer  Mining 
Company  took  hold  of  the  property,  there  seems  to  have  been  a  lull  in 
the  activity  of  the  operations.  In  this  and  succeeding  years  the  old 
Tan-yard  placer  was  reworked  by  hydraulicking.  This  deposit  is  an 
old  river-channel,  and  was  extensively  worked  in  former  days,  being, 
in  fact,  the  site  of  the  first  discovery  of  gold  on  the  property.  The 
width  of  the  channel  is  from  200  to  300  feet,  and  its  length  about  1-J 
miles;  it  is  now  intersected  by  a  large  valley.  The  original  overlay  was 
about  6  feet,  and  the  gravel  from  3  to  6  feet  in  thickness,  underlain  by 
a  thin  bed  of  compact  conglomerate,  cemented  by  iron  oxide;  the  bed- 
rock is  a  siliceous  sericitic  schist.  The  old  miners  in  working  this 
■deposit  did  not  wash  the  overlay,  nor  did  they  take  up  any  part  of  the 
bed-rock.  In  reworking,  the  whole  mass  (from  5  to  20  feet  in  thickness) 
was  hydraulicked,  and  as  much  as  4  to  5  feet  of  the  loose  bed-rock  was 
also  torn  up.  Water  was  pumped  about  200  feet  in  vertical  height, 
from  Lynch's  creek  to  a  small  reservoir  situated  at  the  head  of  the  placer, 
from  where  a  portion  of  it  was  delivered  to  the  giant  (2-J-inch  nozzle), 
by  a  force-pump  under  a  pressure  of  80  pounds,  and  the  remainder  run 
directly  through  the  ground-sluices  to  carry  off  the  tailings.  Six  men 
were  employed  in  cleaning  bed-rock,  and  two  at  the  sluices.  It  is  stated 
that  a  handsome  profit  was  realized  by  this  work. 

In  1885  a  5-stamp  mill  was  erected  and  run  on  ores  produced  in 
prospecting  work.  In  1887  an  adit-level  (A,  fig.  31),  1200  feet  in 
length,  was  driven  into  the  hillside  under  the  main  ore-deposit,  and  the 
mine  was  opened  from  below  by  a  raise,  which  was  at  the  same  time 
used  as  a  chute,  connecting  with  the  open  pit  above.  The  stoping  was 
carried  on  overground,  and  the  material  taken  out  through  the  tunnel. 
In  1888  a  40-stamp  mill  was  erected,  and  started  up  in  May,  1889.  A 
Thies  chlorination  plant  was  added  in  1892,  and  operated  for  a  short 
time  during  1893.  From  that  date  until  June,  1895,  the  mine  was  idle, 
but  at  that  time  preparations  were  being  made  for  starting  work  again. 
10 


146 


GOLD    MINING    IN    SOUTH    CAROLINA. 


Figure  31  represents  the  plan  of  the  Brewer  mine  as  it  is  at 
present  developed.  It  consists  of  the  large  open  pit  (P),  150  feet 
in  depth,  about  200  by  250  feet  on  the  surface,  and  100  by  180  feet  in 


Fig.  31. — Plan  of  Brewer  Mine,  Chesterfield  County,  S.  C.  Scale,  1  inch=120  feet 
A,  adit-level,  1200  feet  long ;  C,  north  cut,  10  feet  deep;  D,  drift,  150-foot  level:  G,. 
granitic  dikes ;  O,  streaks  of  best  ore  ;  P,  bottom  of  main  pit,  150  feet  deep ;  W,  west 
cut,  50  feet  deep  ;  a  a,  surface  line  of  open  cut;   b  b,  150-foot  level. 

the  bottom.  The  ore-body  has  been  further  explored  by  a  drift  (D)r 
on  the  bottom  level,  extending  430  feet  in  a  northerly  direction,  and 
being  in  ore  all  the  way.     The  tunnel  (A)  is  laid  with  narrow-gauge 


N 


* 


- 


/ 


TREATMENT    OF    SULPHURET    ORES    AT    CHARACTERISTIC    MINES.         147 

track,  over  which  the  ore  is  hauled  to  the  mill  by  a  small  locomotive. 
This  tunnel  is  drained  by  a  wooden  gutter  situated  in  the  center  of  the 
track  line.  At  present  ore  is  being  quarried  in  the  west  cut  (W)  near 
the  surface,  from  where  it  falls  to  the  bottom  of  the  pit  (P),  and  is  hauled 
to  the  mill  through  (A).  The  40-stamp  mill,  which  was  not  in  oper- 
tion  when  visited,  is  situated  about  a  quarter  of  a  mile  east  of  the  mine, 
on  the  west  bank  of  Lynch's  creek.  It  is  of  the  Western  type,  built 
by  Eraser  &  Chalmers.  The  weight  of  the  stamps  is  900  pounds.  The 
mortars  are  15  inches  wide  at  the  lip,  and  are  fitted  with  front  inside 
plates  and  30-mesh  steel  wire  screens.  The  outside  plates  of  silvered 
copper  are  8  feet  long  by  54  inches  wide.  Below  the  plates  is  situated 
a  line  of  pointed  boxes,  serving  simply  as  amalgam-traps,  which  dis- 
charge 2  feet  above  the  bottom  to  four  Frue  vanners  with  6-  by  14-foot 
belts.  This  is  one  of  the  most  substantial  and  best  constructed  mills  in 
the  South.     (Plate  X.) 

The  chlorination  plant  consists  of  2  revolving-pan  furnaces,  2  barrels, 
8  filters,  2  stock-tanks,  and  8  precipitating-vats  of  the  same  construc- 
tion and  arrangement  as  at  the  Haile  mine  (see  pp.  139-142). 

When  the  mill  was  last  operated  (in  1893),  the  object  was  to  put 
through  as  much  material  as  possible;  5  to  6  tons  of  ore  per  stamp  were 
milled  in  24  hours,  with  4-inch  drop,  90  drops  per  minute,  crushing 
through  a  20-mesh  screen.  Naturally,  the  pulp  flowed  over  the  plates 
without  a  large  portion  of  it  coming  in  contact  with  them;  and,  with 
only  4  vanners,  the  ultimate  loss  in  tailings  was  so  great  as  to  leave  little 
if  any  profit.  The  concentrates  that  were  obtained  ran  from  $15  to  $20. 
About  50  per  cent,  of  the  gold  in  the  ores  is  free,  and  of  the  amount 
saved  in  amalgamation  50  per  cent,  was  in  the  battery  and  on  the  inside 
plate.  The  cost  of  mining  and  milling  at  the  Brewer  mine,  as  prac- 
ticed above,  is  given  at  75  cents;  and  the  total  cost  (including  mainte- 
nance, salaries,  etc.)  at  $1  per  ton  of  ore  mined. 

Laboratory  experiments  with  cyanide,  and  others  with  chlorination 
in  bulk  (the  latter  by  Mr.  P.  G.  Lidner),  have  been  tried  at  the  Brewer, 
but  proved  unsuccessful.  In  the  latter  part  of  1895  cyanide  experi- 
ments were  again  undertaken  with  reported  favorable  results. 


CHAPTER  VII. 

SOME  CONCLUSIONS  CONCERNING  GOLD  MIXING  IN 

NORTH  CAROLINA  AND  ADJACENT  SOUTH 

APPALACHIAN  REGIONS. 

Bonanzas,  in  the  general  meaning  of  that  term,  have  not  been  found 
in  North  Carolina  nor  in  the  adjacent1  South  Appalachian  regions,  and 
probably  never  will  be,  unless  we  except  rich  pockets  of  limited  extent 
which  for  a  time  might  prove  to  be  such  to  the  individual  operator  or 
tributor.  The  "Western  saying  that  "  A  good  gold  mine  is  one  which 
will  pay  dividends  under  poor  management/'  would  exclude  all  South- 
ern gold  mines  from  even  this  distinction.  There  are,  however,  a  few 
mines  in  the  south,  notably  the  Haile  and  the  Eranklin,  which,  under  able 
management,  fully  conversant  with  all  the  requirements  and  exigencies 
of  the  case,  have  been  developed  into  remunerative  business  enterprises. 
The  wide  distribution  and  the  variety  of  the  auriferous  deposits  through- 
out the  South  do  not  preclude  the  possibility  of  these  mines  serving  as 
examples  for  a  larger  number  of  operations,  instead  of  being  isolated 
cases  as  at  present. 

By  far  the  greater  portion  of  the  gold  that  has  been  produced  in  the 
South  was  derived  from  the  placers,  including  bottom  and  sidehill 
gravels,  as  well  as  auriferous  saprolites  and  decomposed  vein  out- 
crops. From  such  deposits  the  cream  has  been  worked  off,  and 
what  remains  are  the  old  gravel  heaps  and  such  virgin  ground  as 
in  the  earlier  days  proved  inaccessible  to  water  and  unprofitable  for 
primitive  methods,  or  was  overlooked  by  the  prospectors.  Of  the  latter 
class  the  Crawford  mine,  described  on  pp.  91—95,  is  an  example.  Al- 
though the  earlier  prospecting  for  gravel  deposits  was  carried  on  in  a 
thorough  manner,  there  were  no  doubt  large  plantations  on  which  such 
work,  especially  in  the  fertile  bottoms,  was  not  countenanced.  It  is  also 
probable  that  deeper  lying  gravel-channels,  of  which  there  are  no  indi- 
cations on  the  surface,  remain  to  be  exploited,  as,  for  instance,  in  the 
South  Mountain  and  Dahlonega  districts.  The  installation  of  pumps 
(or  where  these  have  been  unsuccessfully  used,  the  erection  of  improved 
or  more  economic  plants),  as  well  as  more  thorough  and  extensive  sur- 
veys for  ditch  lines,  may  open  up  much  ground  which  was  formerly  in- 
accessible to  water.  Hydraulicking  under  direct  pressure  from  a  pump 
may  in  many  cases  be  feasible,  and  may  prove  more  economical  as  far  as 
plant  is  concerned. 


SOME    CONCLUSIONS    CONCERNING    GOLD    MINING.  149 

Bottom-gravel  mines  were  operated  in  the  earlier  days  almost  entirely 
by  pitting,  draining  the  excavations  with  water-wheels,  and  raising  the 
gravel  by  hand  to  rockers  and  sluice-boxes,  the  tailings  being  left  in 
large  heaps.  This  work  was  often  done  in  an  unsystematic  manner; 
portions  of  the  ground  could  not  be  worked  at  all;  and,  in  general,  only 
the  richest  gravel  received  attention,  the  overlay  and  the  bed-rock  being 
neglected  entirely.  Some  of  these  gravel  heaps  have  frequently  been 
reworked,  in  one  case  (on  the  Mills  property,  N.  C.)  as  often  as  seven 
times.  The  additional  gold  obtained  in  these  operations  was  partially 
due  to  the  incompleteness  of  the  preceding  washings,  as  well  as  to  the 
subsequent  further  disintegration  of  vein-quartz  carrying  free  gold  and 
sulphurets.  A  number  of  these  old  bottom-placers  may  warrant  a  re- 
munerative reworking  on  a  large  scale,  either  by  the  use  of  giants  and 
bed-rock  sluices  when  sufficient  fall  is  available,  or  where  the  latter 
is  not  the  case  (a  common  feature  in  the  South)  by  the  application  of 
the  hydraulic  gravel-elevator. 

Virgin  placer  deposits  a] so  exist,  which,  on  account  of  the  low  grade 
of  gravel,  or  the  great  depth  of  the  overlay,  could  not  be  profitably 
worked  by  the  more  primitive  methods.  Tor  such,  the  above  appliances 
may  also  furnish  a  solution.  The  Southern  gravel  deposits  are  far  less 
extensive  than  those  of  California  and  New  Zealand,  and  therefore  as 
low  a  grade  of  gravel  cannot  be  worked,  although  the  South  has  cheaper 
labor  in  its  favor.  Systematic  work  has  rarely  been  pursued,  and  rec- 
ords of  such  work  have  not  been  kept.  Tor  this  reason,  as  well  as  on 
account  of  the  unequal  concentration  of  the  gold  in  the  deposits  and  the 
varying  working  conditions  met  with,  it  is  impossible  to  give  limiting 
values  per  cubic  yard  to  guide  operations  in  the  future.  Tor  the  same 
reasons,  preliminary  testing  will  be  difficult,  especially  in  ground  that  has 
already  been  worked. 

In  general,  it  may  be  said  that  the  great  extent  of  the  rock-decompo- 
sition in  the  South  (often  from  25  to  100  feet  in  depth),  and  the  easy 
disintegration  of  the  same  has  resulted  in  a  greater  concentration  of  gold 
in  the  gravel,  considering  the  richness  of  the  ore-bodies  in  place,  than 
in  many  other  gold  fields. 

The  auriferous  saprolites  and  decomposed  vein-matter  have  been  most 
extensively  worked  in  the  Dahlonega  district.  Here  the  decomposed 
material,  in  which  gold  from  the  eroded  vein-matter  is  more  or  less  con- 
centrated, has  to  a  great  extent  been  worked  clown  to  the  harder  rock. 
In  the  Dahlonega  method  of  working,  everything  seems  to  have  tended 
towards  the  simplification  of  the  process  and  plant,  with  the  object  of 
milling  as  large  an  amount  of  loAV-grade  material  as  is  possible  with 
economy  in  labor  and  plant,  irrespective  of  close  working.  Both  on  ac- 
count of  the  greatly  impoverished  material  and  its  increasing  unfitness 


_ 


150  GOLD    MINING    IN    THE    SOUTHERN    APPALACHIANS. 

for  disintegration  with  the  giant,  a  limit  to  this  method  of  mining  must 
ultimately  be  reached  here.  The  ore-bodies  continue  in  depth  and  should 
open  up  a  probably  more  productive  field  in  deep  mining,  with  less  loss 
of  gold  and  more  economical  output. 

Although  the  Southern  gold  field  has  been  known  and  worked  since 
the  beginning  of  the  century,  it  has  not  had  the  benefit  of  such  thor- 
ough and  systematic  vein-prospecting  as  most  of  the  later  discovered 
fields.  It  was  already  a  well-settled  farming  country,  generally  owned 
in  large  plantation-tracts,  when  gold  was  first  sought  after;  and  such 
lands  as  were  unoccupied  were  the  property  of  the  State  governments, 
which  did  not  offer  special  privileges  and  inducements  to  the  develop- 
ment of  the  mining  industry.  Hence  the  Western  system  of  mineral 
lands  and  mining  claims  did  not  exist,  and  the  field  was  not  opened  to 
the  individual  professional  prospector.  The  same  condition  practically 
exists  to-day.  It  is  difficult  to  make  satisfactory  arrangements  with  the 
property  holders  for  prospecting;  and  propositions  for  such  work  from 
outsiders  are  as  a  rule  regarded  with  suspicion.  Even  the  larger  tracts 
owned  at  present  by  mining  companies  have  not  been  prospected  to  any 
extent.  A  notable  exception  to  this  is  the  development  work  carried 
on  by  the  Yonah  Land  and  Mining  Company  in  Georgia.  If  this  ex- 
ample were  followed  by  other  mining  corporations  whose  acreage  runs 
into  the  thousands  while  their  operations  are  limited  to  a  few  square 
rods,  it  would  greatly  help  to  develop  the  possible  gold  resources  of  the 
South  in  the  direction  of  new  discoveries.  We  do  not,  however,  wish 
to  give  the  impression  that  larger  and  more  valuable  ore-deposits  than 
those  already  exploited  are  still  to  be  found;  the  more  easily  recognizable 
and  richer  outcrops  have  been  worked  over,  and  in  any  case  such  finds 
as  may  be  made  will  probably  present  no  new  features. 

In  general,  the  abandoned  mines  present  the  same  features  as  those 
that  are  working.  Judging  from  some  of  the  older  reports  (Silliman, 
Rogers,  Emmons,  etc.),  the  surface  ores  of  these  mines  were  very  rich. 
due  partially  to  local  concentration  near  the  surface  from  the  eroded 
portions  of  the  vein,  and  in  other  cases  perhaps  to  pockets  and  shoots 
of  limited  extent  and  depth.  In  the  earlier  days,  few  of  the  veins 
were  worked  below  the  water-level;  the  abandonment  of  these  older 
mines,  cannot,  however,  always  be  laid  to  the  appearance  of  refractory 
sulphurets.  In  the  sulphuretted  ores  worked  to-day  from  20  to  60  per 
cent,  of  the  gold  is  free,  and  in  many  of  the  earlier  mines,  where  rich  ores 
occurred  in  continuous  shoots,  these  were  followed  down  far  below  the 
water-level  and  the  free  gold  which  they  contained  was  obtained  by 
simple  amalgamation,  as  for  instance  at  the  Gold  Hill  mine  in  Xorth 
Carolina,  where  the  workings  extended  to  740  feet  in  depth.  The  more 
plausible  reasons  for  the  abandonment  of  the  so-called  rich  Southern  gold 


SOME    CONCLUSIONS    CONCERNING    GOLD    MINING.  151 

mines  may  be  attributed  to  the  pinching  out  of  the  ore-shoots  outcrop- 
ping at  the  surface  or  a  diminution  in  the  assay  value  of  the  ore.  It 
is  probable  that  the  more  expensive  and  difficult  operations  at  such 
depths  precluded  the  further  search  for  other  ore-bodies  below  the  water- 
level.  It  must  also  be  remembered  that  as  early  as  1840  at  least  par- 
tially successful  attempts  were  made  to  work  sulphurets. 

In  many  of  the  mines,  however,  the  ore-bodies  were  of  low  grade, 
though  sometimes  of  large  extent,  and  the  small  extraction  of  the  free 
gold  in  the  sulphuretted  ores  did  not  permit  of  a  profitable  continuation 
of  the  work.  As  in  all  mining  regions,  many  other  so-called  plausible 
reasons  are  given  for  the  abandonment  of  the  mines,  as,  for  instance, 
mismanagement,  disputes  among  the  owners,  etc. 

To  determine  the  probable  value  of  a  mine  an  examination  is  of  course 
absolutely  necessary.  A  conclusive  opinion  is,  however,  in  most  cases 
impossible,  even  after  the  mine  has  been  pumped  out  and  examined,  on 
account  of  the  poor  condition  of  the  workings  and  the,  at  best,  limited 
exposures  of  the  ore-bodies.  The  prospective  investor  must,  with  few 
exceptions,  bear  the  cost  of  the  necessary  exploratory  development, 
which  expenditure  must  be  considered  speculative.  A  great  number 
of  the  properties  are  held  at  prohibitory  figures,  and  arrangements  for 
satisfactory  examination  under  option  or  otherwise  cannot  be  made, 
traditional  merit  and  output  being  considered  a  sufficient  proof  of  value 
by  the  owners. 

In  low-grade  highly  sulphuretted  ore-bodies  assays  may  give  a  fair 
indication  of  the  value  of  the  ore  if  the  samples  be  fairly  taken;  but  a 
test  on  a  larger  scale  at  one  of  the  experimental  chlorination  plants,1  in 
cases  where  it  is  intended  to  subsequently  adopt  the  chlorination  process, 
would  be  much  more  conclusive. 

On  higher  grade,  free-milling  ores,  however,  assays,  even  if  taken 
with  care,  will  be  of  little  value;  the  results  will,  in  fact,  often  be  mis- 
leading. In  such  cases  a  mill-test  is  imperative,  and  it  can  generally 
be  made  either  in  the  mill  at  the  mine  itself,  at  some  neighboring  mill, 
or  at  test  mills  especially  operated  for  this  purpose.2 

The  most  feasible  propositions  in  the  South  appear  to  be  the  work- 
ing of  the  larger  low-grade  ore-bodies.  Rich  veins  as  a  rule  have  been 
in  pockets  and  of  small  extent,  more  suited  to  the  operations  of  tributors 
or  small  landowners,  with  the  help,  perhaps,  of  the  wooden  stamp-mill. 
It  is  a  well-known  fact  that  ore-deposits  of  this  uncertain  character  can- 
not be  worked  systematically  by  larger  companies  with  an  extensive 
plant,  and  must  be  left  to  the  individual  miner,  whose  persona]  success 
pays  his  daily  wages,  and  to  whom  an  occasional  strike  is  an  induce- 
ment for  continuous  work. 

Captain  A.  Thiee,  Haile  Mine,  S.  0.,  and  Mecklenburg  Iron  Works,  Charlotte,  X.  C. 
2  Mecklenburg  Iron  Works,  N.  C,  and  the  Salisbury  Supply  Co.,  Salisbury,  N.  U. 


152 


GOLD    MINING    IN    THE    SOUTHERN    APPALACHIANS. 


Systematic  work  can  only  be  pursued  where  the  ore-bodies  are  large 
and  continuous  enough  to  warrant  the  establishment  of  a  regular  plant 
for  mining,  milling  and  reduction  of  the  ores.  The  question  of  quantity 
means  more  than  that  of  quality,  so  long  as  the  former  does  not  fall 
below  a  certain  limit. 

Among  such  may  be  classed  the  wide  lenticular  bodies  of  auriferous 
and  pyritic  slates,  as  at  the  Haile  and  Russell  mines,  and  the  persistent 
and  continuous  quartz-veins  of  sufficient  width,  such  as  at  the  Reimer 
and  Capps  mines.  The  more  continuous  and  stronger  ore-leads  of  the 
Dahlonega  type  may  also  be  included  here,  such  as  at  the  Lockhart  and 
the  Franklin  mines,  which  are  at  present  being  worked  as  deep  mines, 
as  well  as  those  which  have  so  far  been  worked  by  hydraulic-king,  like 
the  Hand,  Singleton,  Findley,  etc.,  mines. 

In  some  localities  smaller  or  irregular  quartz-veins  lying  close  to- 
gether have  been  worked  separately;  it  may  prove  feasible  to  mine  these 
together  as  a  body  of  low-grade  ore,  especially  where  the  intervening 
and  adjoining  country-rock  is  to  some  degree  auriferous,  as  at  the  Rocky 
River  mine. 

Such  ores  as  are  alluded  to  may  be  said  to  average  between  $3  and 
$7  per  ton.  There  are  exceptional  cases  of  richer  ore-bodies  which  have 
shown  considerable  continuity,  as,  for  instance,  at  the  Phoenix  mine; 
but  here,  as  is  usual,  the  size  of  the  vein  and  hence  the  quantity  of  the 
ore  decreases  proportionately  with  the  improvement  in  the  quality. 

Almost  without  exception,  a  profitable  extraction  from  Southern  gold 
ores  can  only  be  attained  by  supplementing  amalgamation  with  con- 
centration of  the  sulphurets  and  by  subsequent  treatment  of  the  latter. 
The  practically  universal  adoption  of  the  stamp-mill  in  the  South  verities,, 
as  in  other  gold-mining  regions,  its  more  general  applicability  for  crush- 
ing compared  with  other  machinery.  The  two  types  of  stamp-mills  more 
especially  characteristic  of  the  South,  each  having  its  own  field  of  action, 
have  been  described  on  pages  111  and  119.  The  milling  practice  varies 
greatly,  as  might  be  expected  from  the  extremely  variable  character  of 
the  ores. 

All  of  the  Southern  ores  contain  at  least  a  portion  of  their  gold  in 
the  free  state,  and  excepting  where  other  ingredients  offer  serious  ob- 
stacles, or  where  a  smelting  process  is  intended,  concentration  is  best 
preceded  by  amalgamation,  so  as  to  obtain  the  free  gold  as  soon  as  pos- 
sible and  not  endanger  it  to  loss  in  subsequent  treatment.  Especially 
where  the  sulphurets  are  coarse  and  the  crushing  is  not  fine,  a  prelimi- 
nary sizing  in  hydraulic  classifiers  and  spitzkastens,  and  the  treatment 
of  each  size  on  a  separate  vanning  machine,  is  advisable.  There  has 
been  a  tendency  to  overcrowd  these  machines  in  the  South;  a  saving  of 
original  cost  here  is  but  poor  economy.     It  would  seldom  be  advisable 


SOME    CONCLUSIONS    CONCERNING    GOLD    MINING.  153 

to  use  less  than  two  4-foot  belts  to  every  five  stamps.  The  degree  of 
concentration  (cleanness  of  the  concentrates)  must  depend  upon  the  ratio 
between  the  cost  of  subsequent  treatment  per  ton,  on  the  one  hand,  and 
a  greater  loss  in  tailings  occasioned  by  close  concentration  on  the  other, 
the  cost  of  concentration  itself  being  practically  the  same  in  either  ex- 
treme. 

For  the  economical  treatment  of  the  concentrates  chlorination  by 
the  Thies  process  furnishes  in  almost  all  cases  a  ready  solution.  The 
process  is  a  simple  one  and  is  not  patented;  the  cost  of  plant  is  com- 
paratively small,  and  the  percentage  of  extraction  is  high  (94  to  97  per 
cent.).  It  has  been  in  active  operation  on  a  continuous  working  scale 
at  the  two  most  successful  mines  in  the  South  (Haile  and  Franklin 
mines).  The  presence  of  copper  is  objectionable  in  this  process,  as  it 
increases  the  consumption  of  chemicals,  and  if  in  too  large  a  quantity 
it  may  preclude  the  adoption  of  the  process.  At  the  Phoenix  mine,  N. 
C,  ores  running  as  high  as  3  per  cent,  copper  were,  however,  success- 
fully treated.  Ingredients  which  make  dead-roasting  difficult  may  also 
add  to  the  cost  of  the  process. 

Sulphuret  ores  assaying  only  $3  per  ton,  when  existing  in  exten- 
sive bodies,  so  as  to  permit  operations  on  a  larger  scale,  other  condi- 
tions being  favorable,  might  be  worked  at  a  profit  by  the  application 
of  this  process. 

Should  concentration,  on  account  of  the  too  finely  divided  condition 
of  the  gold  and  sulphurets,  prove  impossible  without  a  heavy  loss  in 
tailings,  the  cyanide,  bromination  or  Swedish  chlorination  process  might 
prove  of  value  for  a  direct  treatment  of  the  ore;  or  the  ore  might  be 
treated  in  bulk  by  the  modification  of  the  Thies  process  in  use  at  Dead- 
wood,  Dakota;  or  by  the  Thies  process  proper  on  an  enlarged  scale, 
using,  if  necessary,  closed  filtering-tanks  under  pressure.  In  all  of  the 
above  previous  roasting  is  necessary,  excepting  perhaps  in  the  cyanide 
process.  Attempts  with  the  latter  have  so  far  been  unsuccessful.  It 
will  be  of  interest  to  watch  the  outcome  of  the  plant  at  the  Russell  mine, 
K".  C.  Lack  of  success  in  the  use  of  cyanide  cannot  always  be  laid  to  its 
lack  of  applicability;  it  certainly  has,  however,  this  disadvantage,  that  it 
requires  a  careful  experimental  trial,  best  made  on  a  large  scale  and 
therefore  expensive,  as  well  as  a  continuous  supervision  afterwards  by 
an  experienced  chemist,  together  with  more  or  less  skilled  assistance, 
which  is  a  requirement  not  always  conformable  with  Southern  con- 
ditions. 

A  small  class  of  the  Southern  ores,  referring  particularly  to  those  con- 
taining lead,  copper  and  zinc,  would  have  to  be  treated  by  -inciting.  A 
smelting  plant  would,  however,  only  prove  a  financial  success  under  the 
concerted  action  of  all — or  at  least  most — of  the  mine-  producing  such 


_ 


154         GOLD  MINING  IN  THE  SOUTHERN  APPALACHIANS. 

ores,  a  state  of  affairs  which,  under  the  present  condition  of  gold  mining 
in  the  South,  seems  difficult  to  attain.  Several  attempts  have  been  made 
to  gain  this  end,  but  have  not  been  successful. 

Taken  as  a  whole,  the  gold  ores  of  the  Southern  Appalachians  present 
no  greater  difficulties  of  treatment  than  those  of  other  fields,  the  dis- 
tinguishing feature  being  perhaps  their  large  variety,  which  makes  a 
close  study  of  each  separate  ore-body  necessary. 

As  to  the  cost  of  labor  in  the  South,  it  may  be  said  that  while  it  is  low 
compared  to  that  of  the  Western  mining  districts,  and  unskilled  labor 
can  be  obtained  at  especially  low  cost,  skilled  labor  commands  about  the 
same  wages  as  throughout  the  East.  It  will  be  found  here,  as  in  other 
places,  that  the  laborer  is  worthy  of  his  hire.  Some  difficulty  may  be 
experienced  in  obtaining  suitable  labor,  especially  in  those  districts 
where  no  active  mining  work  has  been  going  on.  In  general  there  are 
no  mining  camps,  in  the  Western  sense  of  the  word,  and  hence  no  regular 
mining  population  that  might  otherwise  engender  a  more  energetic  min- 
ing spirit. 

Among  the  facilities  for  operations  in  the  South  are  the  climate, 
which  permits  continuous  working  throughout  the  year:  the  accessibility 
of  the  mines  to  railroad  lines,  and  their  comparative  proximity  to  in- 
vesting Eastern  capital.  Lumber,  timber  and  cord  wood  can  be  obtained 
at  very  low  cost.  Mining  supplies  and  machinery  are  furnished  from 
several  central  points  in  the  field  (Salisbury,  Charlotte,  Daklonega, 
Atlanta).  Water-power — in  most  cases,  however,  undeveloped — is 
abundant  throughout  a  great  portion  of  the  mining  belt.  Should  a 
revival  in  mining  favor  a  development  of  properties  in  groups,  central 
electric  power  distribution  plants  would  be  practicable  in  most  districts. 

Gold  mining  in  the  South  has  its  favorable  features,  which  should 
facilitate  the  economic  working  of  the  ore-deposits  as  legitimate  business 
undertakings,  with  close  and  intelligent  management.  A  considerable 
number  of  properties  are  at  least  worthy  of  investigation,  and  to  the 
best  of  our  belief,  such  investigations  will  disclose  remunerative  working 
opportunities,  and  will  ultimately  lead  to  a  reasonable  revival  of  gold 
mining  in  the  South.  Examinations  would  be  greatly  stimulated  by 
more  disinterested  co-operation  and  reasonable  demands  of  the  mine 
owners,  ultimately  to  their  benefit.  It  is  to  be  hoped  that  speculative 
investments  in  the  Southern  gold  mines  have  had  their  day,  and  that 
all  future  operations  will  be  conducted  on  such  a  business-like  basis  as 
begets  confidence  and  stabilitv. 


NDEX 


T 


Abandonment  of  mines,  reasons  for. 150,  151 

Abbeville  county,  S,  C,  mines  in 77 

Adams,   W.   H.,   cited 73 

Age  of  ore  deposits,  Carolina  gold  belt...  18 

Alabama,  distribution  of  mines  in 85-90 

early  discovery  of  gold  in 27 

geological  map  of,  referred  to.  .25 
production    of    gold    and    silver 

in    40,  42 

Alabama    Geological    Survey,    publications 

referred  to  13,   25,  27,  30,   85,   90 

Alabama  gold  belt,  description  of 25 

mines  in    85-90 

Alamance    county,    N.    C,    occurrence    of 

gold    in    45 

Alexander    county,    N,    C,    occurrence    of 

gold  in    68 

Alexander  mine,  N.  C 63 

Allen  (Lalor)  mine,   N.   C 47,  4S 

Allen  Furr  mine,   N.   C 60 

Allerton-Ream  mine,   Md.    71 

Alta  (Idler  or  Monarch)  mine,  N.   C..37,  69 

Amalgamation  mills,  types  of 35 

American  Cyanide  Gold  and  Silver  Recov- 
ery Co.,  referred  to 38,  53 

American  Institute  of  Mining  Engineers, 
Transactions  of,  referred  to  9,   10,  14,  24, 
31,    32,   35,   39,   62,    71,   102,    106,   129,   139. 
American  Journal  of  Science,   referred  to 

27,  28,  73  74 
American   Philosophical    Society,    Proceed- 
ings of,   referred  to 27 

Ammons-Branch  mine,  N.  C 70 

Anna   Howe  mine,  Ala 85,  86 

Anna  Howe  Extension  mine,  Ala 85,  86 

Anson  county,  N.  C,  mines  in 57 

Appalachian  (Coggins)  mine,  N.   C 53 

Appomattox    county,    Va.,    occurrence    of 

gold   in    76 

Arbacoochee,    Ala.,    early    mention    of 

ground-sluicing    30 

Arbacoochee  Hydraulic  Company,  referred 

to    85 

Arbacoochee  mining  district.  Ala 85 

Argentiferous  ores   39,  48-51,  58 

Arlington  mine,  N.  C 63 

Arminius  pyrite  mine,  Va 14,   73 

Arrastra,   use  of 33 

Ashe  county,  N.  C,  auriferous  copper  ores 

of    14,    70 

Assays,  value  of   151 

Atlas  mine,   N.    C 57,    60 


PAGE 

Auraria,  Ga.,  early  mining  population  of. 29 
Auriferous   copper  ores..  14,   18,   45,    46,   48, 

51.    70 

Auriferous  garnets   24 

Bailey  (Hamilton)  mine,  N.  C 57 

Baker  mine,  N.  C 68 

Bame  mine,   N.   C 57,   60 

Barlow  mine,    Ga 80 

Barnhardt  mine,   N.   C 62 

Barnhardt  vein,   Gold  Hill,  N.   C 58,   59 

Barrier  mine,   N.    C . 62 

Barringer  mine,   N.    C 32,    56 

Bartlett   lead-zinc-oxide    process 37 

Barton  county,  Ga.,  occurrence  of  gold  in. 82 

Bast  mine,  Ga 80 

Bat-Roost  mine,  N.   C 57 

Beason  mine,  X.  C 45 

Beaver-Dam  mine,  N.  C 30,  52 

Bee-Mountain  mine,   N.  C 68 

Bechtler,  A.  referred  to 41 

C.  referred  to 41 

C.  Jr.,  referred  to 41 

Bechtler   coinage   of  gold   in   North    Caro- 
lina     41,   42 

Becker,  Geo.  F.,  cited.  .9,  11,  13,  14,  18,  22, 

23,  26,  77 
Beguelin  (Blauvelt)  mine  (see  Haile  mine) 

126-131 

Bell  mine,   N.    C 56 

Belzora  mine,  Va 75,  76 

Benham    and    Helmer,    Messrs.,    referred 

to     107 

Bennifield  mine,  Ala 86 

Bethesda   mine,   Md 71 

Bethesda  Mining  Co.,  referred  to 71 

Betz  mine,   Ga SO 

Big-Bird  mine,  Va 75,  76 

Biggers  (Nugget)  mine,  N.  C 60,  61 

Bigley  mine,   Ga 80 

Black  mine,  N.  C 47 

Blake  crushing  system 35.  126 

Blake,  T.  A.,  referred  to 126 

Blake,  Wm.  P.,  referred-  to 24,  31 

Blankets,   use  of 36 

Blauvelt  (Beguelin)  mine  (see  Haile  mine) 

126-131 

Bloomer,  Mr.,   referred  to 60 

Blount   county,   Tenn..   occurrence  of  gold 

in    90 

Blue  Hill  mining  district,  Ala r>0 

Bonner   mine.   Ala 90 

Bonnie-Belle  (Washington)  mine.  N.  C....63 


_Li 


/ 


156 


INDEX. 


PAGE 

Booker   mine,    Ya 76 

Boston  Kennesaw  Mining  Co.,  referred  to.82 

Bowles   mine,    Va 75 

Boylston  mine,  N.  C ..69,  70 

Brackettown  mines,  N.   C 69 

Bradford  jig   36 

Brawley  mine,   N.   C 63 

Brewer  mine,   S.   C 26,  38,  77,  144-147 

Brewer  Mining  Co.,  referred  to 145 

Brewer,  ¥m.  M.,  referred  to 13,  86 

"  Brickbat  "  rock,  defined 21 

Bright  mine,  N.   C 52 

Brindleton  (Bunker  Hill)  mine,  N.  C 31 

Brindletown,  N.   C,   early  mining  popula- 
tion at   29 

Bromination   process    153 

Brown  mine,  N.  C 57 

Buckingham  county,  Va.,  mines  in 76 

Buckingham   mine,    Va 76 

Bucyrus  Steam  Shovel  Co.,  referred  to..  106 

Buddies,  use  of 36 

Buffalo  mine,  N.  C 60,  61 

Bugbee,  Wm.,  referred  to 75 

Bullion   mine,   N.   C 57 

Bumalo  pits  (Haile  mine) 129,  130,  132 

Bumping  tables,  use  of 36 

Bunker-Hill  (Brindleton)  mine,  N.  C 31 

Bunnell-Mountain  mine,  N.   C 52 

Burke  county,  N.  C,  mines  in 68,  69 

Burns  (Cabin  Creek)  mine,  N.  C...38,  56,  57 

Busby   mine,   Va 75 

Butt  mine,   Ga 79 

Cabarrus  county,  N.  C,  mines  in 60-62 

Cabin-Creek  (Burns)  mine,  N.  C..38,  56,  57 

Cabin  Creek  Mining  Co.,  referred  to 57 

Cagle  mine,  N.  C 57 

Caldwell  county,  N.  C,  mines  in 68 

Calhoun  mine,    Ga 80 

California  mine,  Ala 89 

California  (Tucker)  mine,  N.  C 38,  61,  62 

Caloric  Reduction  Company's  process 39 

Camille   (Royal)  mine.    Ga                 38,  82,  83 
Campbell  Mining  and  Reduction   Co.,   re- 
ferred to   48 

Cane  Creek  gold  deposits,  Tenn 90 

Cane  Creek  mine,  N.  C 69 

Capps  mine,   N.    C 63-66 

Carolina  gold  belt,  description  of 15-18 

in  Georgia.  15,  24,  84,  85 
in    North    Carolina, 

15,   45-68 
in  South  Carolina.  15,  77 

mines  in 45-68,  77,  85 

Carolina-Igneous   gold  belt 13 

Carolina-Slate  gold  belt 13 

Carroll  county,  Ga.,  mines  in 82 

Carroll  county,  Va.,  occurrence  of  gold  in. 76 

Carter  mine,  N.   C 52 

Case,  Wm.  H.,  referred  to 74 

Catawba  county,  N.  C,  occurrence  of  gold 

in    68 

Catawba   (Kings   Mountain)    mine,    N.    C, 

18,  35,  66-68 


PAGE 

Census  Report  of  United  States,   referred 

to     42 

Chambers  county,  Ala.,  occurrence  of  gold 

in     90 

Chance,  H.  M.,  referred  to 56 

Characteristic  deep  mines  described .  115-147 
Characteristic  placer  mines  described.91-115 
Charlotte  county,   Va.,  occurrence  of  gold 

in 76 

Chase-Hill  mine  pits  (Haile  mine), 

127.  129,  131 
Chatham  county,  N.  C,  occurrence  of  gold 

in    ...45 

Chatham  mine,  N.  C 45 

Chattahoochee   (or  Plattsburg)   Gold  Min- 
ing and  Milling  Company's  mines,   Ga..79 

Chemical    processes    37-40 

Cherokee  county,  Ga.,  mines  in 81,  82 

Cherokee  county,  N.  C,  placer  mining  in. 70 

Cherokee  mine,    Ga 82 

Chestatee  Company,  referred  to. 79.  101,  102 

Chestatee  mine,  Ga 32.  101-106 

Chestatee  River  dredge  boats 106,  107 

Chester  (Latham)  mine,   Ga 82 

Chesterfield  county,  S.  C,  mines  in 77 

Childs,  Mr.,  referred  to 78 

Chilian  mills,  use  of 33 

Chilton   county,    Ala.,    occurrence   of   gold 

in    90 

Chincapina  mine,  Ala S9 

Chlorination  plant,  illustrations  of...  139-141 
Chlorination  processes,  introduction  of.37,  38 

Chlorination  process  at  Brewer  mine 147 

Franklin  mine   .  .125 
Haile  mine.   137-142 

Phoenix  mine 62 

Reimer  mine 119 

Royal  mine S3 

Tucker  mine 62 

Chulafinnee  mining  district,   Ala S6 

Cincinnati  Consolidated  mine.  Ga 32,  SI 

Citico  Creek  gold  deposits.  Tenn 90 

Clark  mine,  N.  C 63 

Clay  county,  Ala.,  mines  in S9,  90 

Clay  county,  N.  C,  mine  in 70,  84 

Cleburne  county,  Ala.,  mines  in S5-87 

Cleveland  county,  N.  C,  petty  mining  in. 69 

Clegg  mine,  N.  C 57 

Clingman,  T.  L.,  referred  to 31 

Clopton  mine,    Ga 38,  82 

Clyburne  mine,  S.   C 77 

Cobb  county,  Ga.,  occurrence  of  gold  in.. 82 

Coco  Creek  gold  deposits,  Tenn 90 

Coggins  (Appalachian)  mine,  N.  C 53 

Collins   mine,    Ga SI 

Collins  mine,  Va 75,   76 

Columbia  county,   Ga.,  mines  in S4,  85 

Columbia  Gold  Mining  Co.,  referred  to... 75 

Columbia  mine,   Ga S5 

Columbia  Mining  Co.,  referred  to 57 

Concentration  methods   36 

Conrad  Hill  mine,  N.   C IS.   39,  51 


INDEX. 


157 


PAGE 

Contents,    table   of 3-5 

Cooper  Gold  Mining  Co.,  referred  to 93 

Coosa  county,  Ala.,  occurrence  of  gold  in. 90 

Copper  ores,  auriferous 14,  18,  45, 

46,  48,  51,  70 

Cost  of  chlorination  plants 119 

chlorinating  at  Franklin  mine.. 125 
"  "    Haile  mine    . . .  .143 

diamond     drilling     at     Franklin 

mine     124 

labor  at  Arminius  pyrite  mine... 74 

"       "    Crawford  mine   94 

"       "    Franklin    mine    125 

"    Haile  mine 143 

"       "    Idaho   mine    89 

"       "    Kings  Mountain  mine.. 67 

"       "    Parker   mine    56 

"       "    Pinetucky  mine    88 

"       "    Reimer  mine 117,  119 

labor,    general   discussion 154 

milling  at  Franklin  mine 125 

"         "    Parker  mine    55 

milling,     concentrating,     roasting 
and      chlorinating      at     Reimer 

mine    121 

mining  at  Phoenix  mine .62 

mining,    crushing    and    tramming 

at  Franklin  mine 125 

mining    and    milling    at    Brewer 

mine     147 

mining  and  milling   at   Crawford 

mine   94 

mining  and  milling  in  Dahlonega 

district     114 

mining     and     milling     at     Idaho 

mine     89 

mining     and     milling     at     Kings 

Mountain   mine    67 

mining   and   milling   at   Lockhart 

mine     116 

mining  and  milling  at  Lucky  Joe 

mine     86 

mining  and  milling  at  Slate  Hill 

mine     74 

roasting  at  Franklin  mine 125 

"  "    Haile  mine    143 

"  "    Reimer  mine    119 

supplies  at  Franklin  mine 125 

"  "    Haile  mine   143 

stamp  mill  equipments 113,  119 

Cox  mine,  Ga 82 

Crandall    hydraulic    gravel    elevator, 

32,   102-105 

Crandall,  W.  R.,  cited 102 

Crawford  mill    35 

Crawford  (Ingram)   mine,   N.   C 54,  91-95 

Crawford  Mining  Co.,  referred  to 93 

Creighton  (Franklin)  mine,  Ga.81,  82,  121-125 
Creighton  Mining  and  Milling  Co.,   refer- 
red  to    121,   123 

Cross,  Jno.,  referred  to 83 

Cross  mine,    S.   C.    (see  Haile  mine), 

127,  129,  130,  131 


PAGE 

Crowell  mine,  Stanly  county,  N.  C 56 

Crowell  mine,  Union  county,  N.  C 63 

Crown  Point  mine,  Ala 86 

Crumpton  mine,  Ala 86 

Crutchfield  mine,  Ala 85 

Culp  (Little  Fritz)  mine,   N.   C 56 

Culpeper  county,  Va.,  mines  in 72 

Culpeper    mine,    Va 72 

Currahee   mine,    Ga 80 

Cyanide  process,  application  of 38,  153 

Cyanide  process  at  Brewer  mine 147 

Cabin     Creek     (Burns) 

mine  38,  57 

Franklin  mine... 38,  123 

Gilmer  mines 38 

Gold  Hill  mines.. 38,  60 

Jones  mine  47 

Moratock  mine  ...38,  54 

Reimer  mine    121 

Russell  mine 38,  53 

Sawyer  mine 38,  47 

Dahlonega,  Ga.,  early  mining  population. 29 
Dahlonega  method  of  mining  and  milling, 

general  description  32,  107-115 

Dahlonega  method  of  mining  and  milling, 

future  of  149,  150 

Dahlonega  method  of  mining  and  milling, 

at  Hedwig  mine 114,  115 

Dahlonega  method  of  mining  and  milling, 

at  Parker  mine ., 55 

Dahlonega  mining  district,  Ga...80,  107-115 

Dahlonega  Mint,  the,  referred  to .80 

Darlington,   Wayne,  referred  to 61 

Davidson  county,  N.  C,  mines  in 47-51 

Davidson  Hill  mine,  N.  C 63 

Davie  county,  N.  C,  occurrence  of  gold  in. 68 

Davis   chlorination  process.... 38 

Davis  and  Tyson  Metallurgical  Works,  re- 
ferred to  38 

Davis  mine,  Halifax  county,  N.  C 43 

Davis  (Dutton  or  Morris  Mt.)  mine,  Mont- 
gomery county,  N.  C 53 

Davis   (Ophir)    mine,   Montgomery   county, 

N.   C 52 

Davis  mine,  Union  county,  N.  C 63 

Davis  Mountain  mine,   N.   C 47 

Dawson  county,  Ga.,  mines  in 81 

Dean   (St.   George)  mine,    Ga 79 

Decomposition  of  rocks 11 

Deep  Flat  mine,  N.  C 52 

Deep  River  mine,  N.   C 45 

Delft  mine,   N.   C 47 

Derr  mine,  N.  C. 66 

Designolle  process    39 

De  Soto  Mining  Co.,  referred  to 144 

Diabase    dikes,    influence    of    on    ore-bod- 
ies   .16,  63,  126 

Diamond  drilling  at  Capps  mine 64-66 

Franklin  mine   123 

Haile  mine   132 

Pinetucky  mine  . . .  .SS 

Distribution  of  mines  in  Alabama 85-90 

Georgia    78-85 

Maryland  71 


v> 


158 


IXDEX. 


PAGE 

North    Carolina.  .43-70 
South   Carolina.. 76-78 

Tennessee    90 

Virginia   71-76 

Dixon  mine,  N.  C 68 

Dorn  mine,  S.  C 77 

Douglas  county,  Ga.,  occurrence  of  gold  in. 82 

Drag-mill,    use  of 33 

Dr.  Charles  mine,  Ga 81 

Dredge  mining .32,  106,  107 

Dry  Hollow  mine,  N.  C 52 

Duffle  mine,  N.  C 66 

Duncan  mine,  Va 76 

Dunn  mine,  N.  C 26,  63 

Dunns  Mountain  mine,  N.  C 57 

Dutch  Creek  mine,  N.  C 60 

Dutchmans  Creek  mine,  N.  C 52 

Dutton  (Davis  or  Morris  Mt.)  mine,  X.C..53 

Dyne  Creek  Co.,  Ala.,  referred  to 87 

Eades  mine,  Va 75,  76 

Eagle  mine,   Va 72 

Eames,  R.,  referred  to 38,  58,  93 

Early  concentrating  methods 36 

Early  discoveries  of  gold  in  the   Southern 

states    26,   27 

Early  discovery  of  auriferous  veins 32 

Early  milling  appliances 33-36 

Early     mining     and     metallurgical     prac- 
tice     29-40 

Early  mining  operations 27-29 

Early  records  of  vein  mining 32 

Earnhardt     (Randolph)     vein,     Gold     Hill, 

N.    C 34,   58,  59 

Eastern  Carolina  gold  belt,  description  of, 

14,  15 
mines  in.  .43,  45 

Eckels    mine,   Ala 87 

Edgefield  county,   S.   C,  mines  in 77 

Egypt   mine,    Ga 85 

Electrolytic  chlorination  process 38 

Elevators,     hydraulic     gravel,     32,     98,     99, 

102-105 

Ellet,  Wm.  H.,  cited 31 

Ellis  mine,  Va 72 

Elrod  mine,   Ga 80 

Elwood  mine,   N.   C 69 

Embrey  concentrating  machine 36 

Emmons,  E.,  cited 27,  34,   5S 

Emmons,   S.  F.,  cited 14,  71 

Engineering  Magazine,  referred  to 10 

Engineei'ing  and  Mining  Journal,   referred 

to 50,  74,  S6 

Etowah  mine,   Ga , SI 

Eureka  mine,  N.  C 47 

Eva  Furr  mine,   N.  C 60 

Faggart  mine,   N.    C 62 

Fair  Mining  and  Milling  Co.,  referred  to..SS 

Farrar  mine,  X.  C GO 

Farrow  Mountain  mining  district,  Ala.... 90 

Fauquier  county,   Va.,   mines  in 72 

Fentress  (North Carolina)  mine,  N.  C..45,  46 

Ferris   mine,    X.    C 04,   66    I 

Fesperman,  F.  A.    referred  to 91    ' 


Filer  and  Stowell  Co.,  referred  to 109 

Findley  mine,  Ga.., SO,  109 

Fish  Trap  mine,   Ga 80 

Fisher,  Geo.,  referred  to 75 

Fisher,   Jas.,   referred  to 75 

Fisher  lode,  Va 14,  74 

Fisher  mine,   Va 75 

Fisher  Hill  mine,  N.   C 45 

Flint  pit  (Haile  mine) 129,  130 

Floyd    county,    Va.,     occurrence    of    gold 

in    71,   76 

Fluvanna  county,  Va.,   mines  in 75,  76 

Ford  mine,  Va 7$ 

Forsythe  county,  Ga.,   mines  in 81 

Fowler  mine,  Ga SI 

Franklin  county,  X.  C,  mines  in 43,  45 

Franklin   (Idaho)  mine,   Ala 89 

Franklin  (Creighton)  mine,   Ga...23,  24,  38, 
81,  82,  121-125 

Franklin  mine,   Va 72 

Freemilling  ores,  treatment  of 32-36 

Freiberg  amalgamation  barrel 35 

Frue  Vanner  concentrating  machine 36 

Frye,  Mr.,  referred  to 106 

Funderburk  mine,    S.   C 77 

Furness  mine,  X  C 62 

Gangue  minerals   18,  24 

Gardiner  mine,  Va 72 

Gardner  Hill  mine,   X.   C 45,  46 

Garnet  mine,   Ga 80 

Garnets,   auriferous    24 

Garnett  and  Mosely  mine.  Va 76 

Gaston  county,  X.   C,   mines  in 66-6S 

Gay  mine,  S.  C 77 

General    conclusions    and    considerations, 

148-154 
Genesis    of    ore    deposits,     Carolina    gold 

belt    17,  IS 

Genesee  Gold  Mining  Co..  referred  to.... 53 
Geological  map  of  Alabama,  referred  to.. 25 
Geological    Survey    of    Alabama,    publica- 
tions referred  to 13,  25,  27,  30,  S5,  90 

Geological  Survey  of  Georgia,  publications 

referred  to 13.  7S 

Geological  Survey  of  Xorth  Carolina,  pub- 
lications referred  to.. 9,  13,  21.  29,  33,   34. 
43,  46,  48,  5S 
Geological  Survey  of  South  Carolina,  pub- 
lications referred  to.  .13,  32,  37.  41.  77.  126 
Geological   Survey  of  United  States,   pub- 
lications referred  to. 11.  13,  IS.  22,  23.  24.  26 
Geological    Survey    of    Virginia,     publica- 
tions referred  to 13 

Geology  of  the  Southern  Appalachian  gold 

belt    11-25 

Georgetown  Valley,  X.  C,  placer  mining.. 70 

Georgia,  distribution  of  mines  in 7S-S5 

early  discoveries  of  gold  in.  .26.  27 
production     of    gold    and    silver 

in    40.  42 

Georgia     Geological     Survey,     publications 
referred   to    13.   7S 


\ 


INDEX. 


159 


PAGE 

Georgia  gold,  belt,   description  of 21-25 

mines  in   78-85 

Georgiana  mine,    Ga 82 

Gibb  mine,  N.  C 62 

Gibson,  Mr.,   referred  to 32 

Gilmer  mines,  Va 38 

Gilmore  mine,  "Va 75 

Glades    P.    O.,    Ga.,     gold    and    monazite 

at    21,  80 

Glenbrook  Mining  Co.,  referred  to 52 

Gold  belt,  the  Alabama,  description  of 25 

mines  in  85-90 

the  Carolina,  description  of.  15-80 
in  Ga.,  15,  24,  84,  85 
in   N.   C...15,  45-68 

in  S.   C 15,  77 

mines    in 45-68, 

77,  85 

the  Carolina-Igneous  13 

the  Carolina-Slate 13 

the    Eastern    Carolina,    descrip- 
tion of   14,  15 

the     Eastern     Carolina,     mines 

in    43.  45 

the  Georgia,  description  of.  .21-25 

mines  in    78-85 

the  Kings  Mountain 13 

the     South     Mountain,     descrip- 
tion of   18-20 

the  South  Mountain,  in  N.  C.    68-70 
in  S.  C.  77,  78 
mines  in,  68-70,  77,  78 
the     Southern     Appalachian,     de- 
scription  of    11-25 

the    Southern    Appalachian,    di- 
visions of   13 

the    Southern    Appalachian,    ge- 
ology of 11-25 

the  Virginia,  description  of.  13,  14 

mines   in    71-76 

Gold  belts,  minor,  in  Georgia 24,  25 

in  North  Carolina.  .20,  21 
Gold  Hill,  N.  C,  map  showing  distribution 

of   veins    59 

Gold  Hill,  N.  C,  population  of  early  min- 
ing camp   29,  58 

Gold  Hill  mines,  N.  C 34,  37,  38,  57-60 

Gold  Hill  Mining  Co.,  referred  to 58 

Gold  Knob  mine,  X.   C, 57,  60 

Gold  milling  machinery 33-36 

Gold  and  Silver  production,  statistics.  .40-42 

Goldberg  mining  district,  Ala 88,  89 

Golden  Eagle  (Price)  mine,  Ala 87 

Golden  Gate  mine,  S.  C 78 

Golden  Valley  ore  zone 20 

Golden  Valley  placer  mines,  X.  C 69 

Goldville,  Ala.,  population  of  early  mining   . 

camp     29 

Goldville  mining  district,   Ala 90 

Goochland  county,  Va.,   mines  in 75,  76 

Goodman  mine,  X.  C 57 

Goodwin  mine,   Va 73 

Grampusville  mine,  X.  C 56 


PAGE 

Granville  county,  X.  C,  mines  in 45 

Gravel     elevators,     hydraulic,     32,     98,     99, 

102-105 
Grayson   county,   Va.,    occurrence  of  gold 

in    76 

Greenville  county,   S.  C,  mines  in.... 77,  78 

Greenwood  mine,  Va 73 

Gregory  Hill  mining  district,  Ala 90 

Grindstone  Hill  mine,  Va 73 

Ground-sluicing,  early  mention  of 30 

Guilford  county,  N.  C,  mines  in 45,  46 

Gum  mine,  Ala 90 

Gwinnett  county,  Ga.,  mines  in 81 

Habersham     county,     Ga.,     occurrence    of 

gold  in 78 

Haile  Gold  Mining  Co.,  referred  to 125 

Haile  mine,  S.  C 16,  17,  35,  38,  39,  76, 

77,  125-143 

Haile  pit  (Haile  mine) 129,  130 

Haithcock  mine,  X.  C 54 

Hale  mine,   S.  C 78 

Halifax  county,  X.  C,  mines  in 43 

Halifax  county,  Va.,  occurrence  of  gold  in.76 

Hall,  F.  W.,  referred  to Ill 

Hall  county,   Ga.,   mines  in 80 

Hall  stamp-mill    35,  110-113 

Hamilton,  Benj.,  referred  to 31 

Hamilton  (Bailey)  mine,  X.  C 57 

Hammett  mine,   S.  C 78 

Hancock  placer  mines,  X.  C 69 

Hand-Barlow  Co.,  referred  to 79 

Hand  and  Barlow  ditch,  Dahlonega 108 

Hand  and  Barlow  United  Gold  Mines  and 

Hydraulic    Works    of    Georgia,    referred 


to 


.109 


Hand  mine,  Ga 80,  109 

Hand-mortars,   use  of 33 

Hanna,  Geo.  B.,  referred  to. 10,  13,  26,  41,  42 

Haralson  county,   Ga.,   mines  in 82,  83 

Harland  and  Beard  mine,  X.  C 45 

Harris   mine,   Va 14,  74 

Harrison   (Sawyer)  mine,  Md 71 

Harrison  mine,  X.   C 57 

Hartman    mine,    X.    C 57 

Hearne  mine,   N.   C 54 

Hedwig  mine,  Ga 23,  SO,  114,  115 

Hemby  mine,  X.  C 63 

Henderson  county,  X.  C,  mine  in 69,  70 

Henderson  mine,  X.   C 64 

Hendy  lift  (gravel   elevator) 32,  98,  99 

Herring  (Laughlin)  mine,  X.  C 47 

Hicks-Wise   mine.    Ala S6 

Higginbotham  mine,  Ala S6 

Hill  mine,  X.  C 57 

Historical  notes    26-40,  10S 

Hobbs   mine,   Ala 89 

Hodges  Hill  (Hodgins)  mine,  X.  C 45 

Hodgins  (Hodges  Hill)  mine,  X.  C 45 

Hog  Mountain  mining  district,  Ala 90 

Hogan,   J.,    referred  to 26 

Holland,   Dr.,   referred  to 36 

Holloway  miue,   X.   C 45 

Holtskauser   mine,    X.    C 57 


A  ' 


t 


160 


IXDEX. 


PAGE 

Honey  cut  vein,  Gold  Hill.  N.   C 58,  59 

Hoover  Hill  mine,  N.  C 46,  47 

Horner  mine,    Ga 80 

Horns  Peak  mine,  Ala 89,  90 

Howell   mine,    N.    C 63,  64 

Howes,  Amos,  referred  to 58 

Howie  mine,  N.   C 63 

Howland  mill  35 

Huddleston  mine,   Md 71 

Hughes   mine,    Va 75,  76 

Hunt  mine,   Ga 84 

Hunt  and  Douglas  process 39,  51 

Huntington  mill   35,  36 

Huntsville  ore  zone   19 

Huntsville  placer  mines,   X.   C 69 

Hydraulic     gravel     elevators,     32,     98.     99, 

102-105 

Hydraulic    mining    methods .30-32 

Hydraulic  mining  at  the  Chestatee  mine 

101-106 
Crawford   mine 

92-95 
in    the    Dahlonega    dis- 
trict     108-110 

at  the  Hedwig  mine..  114 
Mills  mine.. 96-101 
Parker  mine. 54,  55 

Portis   mine 45 

Sam   Christian 

mine    52 

Yon  ah    mine. . .  .79 
Hydraulic  pumping  engine  at  the  Findley 

mine    109 

Idaho   (Franklin)   mine,   Ala 89 

Idaho  mining  district,   Ala 88,  89 

Idler  (Alta  or  Monarch)  mine,  X.  C..37.  69 

Idler-Mine  ore  zone  20 

Illustrations,  list  of 6 

Influence   of   diabase   dikes   on   ore-bodies, 

16.  63,  126 
Ingram   (Crawford)  mine,  X.   C....54,  91-95 

Irma  mine,   Md 71 

Isenhour  mine,  X.  C. . . , 60 

Island  Creek  mine,  X  C 52 

Ivy  mine,  Ga SO 

Jack  Brown  mine,    Ga 84 

Jacks  Hill  mine,    X.  C 45,  46 

Jackson  county,  X.  C,  placer  mining  in.. 70 

Jacquish,  Mr.,  referred  to 106 

James  Moore  mine,  Ala 86 

Jamestown     (Vein     Mountain)     mine, 

X.   C 31,   69 

Jarrett  mine,  Ga 78,  79 

Jefferson,    Thos.,    cited 26 

Jesse  Cox  mine,  X.  C 57 

Joel  Reed  mine,  X.  C 60 

Johnston  mine,  Va 73 

Jones  (Keystone)  mine,  X.  C 47 

Josephine  mine,  Ga 80 

Joshua    Hendy    Machine   Works,    referred 

to    98 

Kearney   mine,    X.    C 43 

Kemp  Mountain  mining  district.  Ala 87 

Keystone  (Jones)  mine.  X.  C 47 


Kiggins    mine,    Va 73 

Kin  Mori  mine,   Ga SI 

King   mine,    Ala ■ SO 

Kings  Mountain  gold  belt 13 

Kings   Mountain    (Catawba)    mine.    X.    C, 
18,  35,  66.  67.  68 

Kirkley  mine,  S.  C 77 

Knight,  Mr.,   referred  to 87 

Knott  mine,   S.  C 78 

Knuckelsville,    Ga.,    early   mining   popula- 
tion of  29 

Lalor  (Allen)  mine,  X   C 47.  48 

Lancaster  county,  S.  C,  mines  in 77 

Latham  (Chester)  mine,   Ga 82 

Laughlin  (Herring)  mine,  X.  C 47 

Laurel  mine,   Ala S9 

Lawrence  mine,   Ga 80 

Leach  mine,   S.  C 77 

Lee  mine,  Ala 86 

Lehmann,   G.  TV,   cited 50 

Leopold  mine,  Va 72 

Letter   of   Transmittal 8 

Lewis  mine,  X.  C 63 

Lidner,  P.   G.,  referred  to 38.  147 

Lieber,  O.  M.,  cited 13.  32.  37.  77.  126 

Lightf oot  mine,   Va 76 

Lincoln  county,  Ga.,  mines  in S4.  85 

Lincoln  county,  X.  C,   occurrence  of  gold 

in    68 

Lindsay  mine,  X.   C 45.  46 

List  of  illustrations 6 

Little  mine,  Ga 81 

Little  Fritz  (Culp)  mine,  X.  C 56 

Locke,  A.  G.,  referred  to 106 

Lockhart  mine,   Ga 21,  24,  SO,  115.  116 

Lof tin  mine,   X.   C 47 

London  mine,   Va 76 

Long  mine,   X.    C 63 

Long  Creek  mine,  X   C 66.  67 

Longstreet  placer  mine,   Ga 79 

Loud  mine,    Ga . . . .  < 79 

Louisa  county,  Va.,   gold  mines  in... 73,  74 
pyrite   mines    ...73.  74 

Louisa  mine,  Va 74 

Lowder  mine,  X.   C 54 

Luce  mine,  Va 14.  74 

Lucky  Joe  mine,  Ala S6 

Lumpkin  county,   Ga.,  mines  in SO,  SI 

Lumsden   mine,    Ga 7S 

Macon  county,  X.   G*    occurrence  of  gold 

in   TO 

Magazine  (or  Parker)  Branch  placer-mine. 

x  c 101 

Magruder  mine,   Ga 85 

Mammoth    mine,    Ga SO 

Mann  mine,  X.   C 43 

Mann-Arrington   mine,   X.    C 15.  43.  45 

Map  of  Xorth  Carolina,  showing  distribu- 
tion of  gold  deposits 44 

Map  of  Gold  Hill  mining  district,  showing 

distribution   of  veins 59 

Map,  showing  location  of  mines  and  plant. 

Haile  mine  127 

Map,   showing  plan  of  Capps  mine 65 


INDEX. 


161 


PAGE 

Marks    mine,    Va 75,  76 

Marion  Steam  Shovel  Co.,  referred  to...  107 

Marion-White  mine,    Ala 86 

Marshall  mine,  Va 72 

Martin  Mining  Co.'s  mine,    Ga 79 

Mary-Henry  (Murray)  mine,   Ga 80 

Maryland,  distribution  of  gold  mines  in.  .71 
early  discoveries  of  gold  in. . .  .27 
production    of    gold    and    silver 

in    40,    42 

Maryland  mine,  Md. 71 

Matte-smelting    39 

McCullough  (North  State)  mine,  N.  G, 

39,  45  ,46 
McDowell   county,   N.    C,   mines   in... 68,  69 

McDuffie  county,  Ga.,  mines  in 84,  85 

McGinn   mine,   N.   C 36,  63,  66 

McGuire  mine,    Ga 81 

Mclnnis  mine,   S.   G 77 

McLean  mine,  N.   C 66 

McMackin  vein,   Gold  Hill,  N.   C 58,  59 

McMinn  county,  Tenn.,  occurrence  of  gold 

in    90 

Mears   chlorination   process 37,  62 

Mecklenburg  county,  N.  C,  mines  in.. 63-66 

Mecklenburg  Iron  Works,  referred  to.... 66. 

119,  120,  124,  135 

stamp    mill.. .  .35, 

119,  120 

test   plant.  119,  151 

Meech   mill    35 

Melville  mine,  Va 73 

Mercer  mine,  Ga 79 

Meriweather  county,    Ga.,   mines  in 83 

Merrick  mine,  Ga 80 

Middlebrook  mine,  Ala 86 

Miller  mine,  Ala 86 

Miller  mine,  N.  G 45 

Milling   machinery    33-36 

Milling  practice  at  the  Bonnie  Belle  mine,  63 
Brewer  mine  ....  147 
in  the  Dahlonega  district, 

Ga 110-114 

at  the  Franklin  mine  .  .124 
Haile  mine.  ..135-137 
Hedwig  mine.  114-115 

Idaho  mine 89 

Kings  Mountain 

mine    67 

Lockhart    mine. .  .116 

Parker    mine 55 

Iteimer  mine 119 

Millis  Hill  mine,   N.   G 45 

Mills'  (Statistics  of  South  Carolina),  cited. 26 

Mills,  J.  C,  referred  to 77 

Mills  property,  N.  C,  placer  mines    69,  95-101 

Mineral  Farm  mine,  Ga 82 

Mineral  Hill  mine,   Ga 82 

Mines   in   Alabama 85-90 

Georgia    78-85 

Maryland     71 

North   Carolina    43-70 

South   Carolina    76-78 

11 


PAGE 

Mines    in    Tennessee    90 

Virginia    71-76 

Mining  Magazine,   referred  to 40 

Mining    and    Statistic   Magazine,    referred 

to    31.  32 

Mining,  milling,  and  metallurgical  treat- 
ment of  sulphuret  ores  at  characteristic- 
mines    117-147 

Mining    practice    at    characteristic    placer 

and  free  milling  mines 91-115 

Mining  practice  at  the  Chestatee  mine, 

102-106 
Crawford  mine    92-95 
in     the     Dahlonega     dis- 
trict     107-110 

at    the    Franklin    mine, 

123,  124 
Haile  mine.  .132-135 
Lockhart  mine. 

115,  116 

Mills   mine 96-100 

Minor  gold  belts  in  Georgia 24,  25 

North    Carolina... 20,  21 

Mitchell,   Elisha,    cited 33 

Mitchell   mine,    Va 73 

Monarch  (Alta  or  Idler)  mine,  N.   C..37,  69 

Monazite,  occurrence  of  19,  21,  97 

Monroe  county,   Tenn.,  occurrence  of  gold 

in    90 

Monroe  mine,   Va 72 

Monroe  slates,   described 1G 

Montgomery   county,   Md.,   mines  in 71 

Montgomery  county,  N.   C,  mines  in.. 51-54 
Montgomery    county,    Va.,    occurrence    of 

gold    in    76 

Montgomery  mine,   Md 71 

Montgomery  mine,  N.  C 60 

Moore  county,  N.  C,  mines  in 56,  57 

Moore  mine,  N.  C 63 

Moore  Girls'  mine,  Ga 78 

Moratock  mine,   N.   C 38,  53,  54 

Morganton   ore    zone 19 

Morris  Mountain  (Davis  or  Dutton)   mine, 

N.    C 53 

Morrow  mine,  Va 76 

Morton   mine,    Va 76 

Moss,  Jno.,  referred  to 75 

Moss   mine,    Va 75 

Moss-Back   mine,   Ala 86 

Murray  (Mary-Henry)  mine,  Ga SO 

Nacoochee  Hills  Gold  Mining  Co.'s  mines, 

Ga 70 

Nacoochee  Valley  mining  district,   Ga.TS.  79 

Nancy  Brown  mine,   Ga S4 

Nash  county,  N.  C,  mines  in 43 

Nason,  F.  L.,  referred  to 74 

Negus  mine,    N.    C . 57 

New  Discovery  mine,  X.    C 39,  57 

New  Gold  Hill  Co.,  referred  to 58 

New  London  Estates  Co..  L't'd.,   referred 

to    •• 54 

Nick-Arrington  mine.   N.   C 43 

Nininger,   Mr.,   referred   to 40 


- 


162 


INDEX. 


Nitze,  H.  B.  C 

Nobles  process 


PAGE 

referred  to 13 

35 

North  Carolina,  distribution  of  mines  in, 

43-70 
early  discovery  of  gold  in. 26 
production  of  gold  and  sil- 
ver in   40,  42 

North  Carolina  Geological  Survey,  publica- 
tions referred  to.  .9,  13,  21,  29,  33,  34,  43, 

46,  48,  58 
North  Carolina  (Fentress)  mine,  N.  C.  .45,  46 
North  Carolina  Smelting  Co.,  referred  to. 49 
North   State   (McCullough)   mine... 39,  45,  46 

Notes  on  Virginia  (Jefferson),  cited.. 26 

Nuggett  (Biggers)  mine,  N   C 60,  61 

Old  Field  mine,  Ga 84 

Oliver   mine,    N.    C 26,  66 

Olmstead,    Prof.,    cited 28 

Ophir  (Davis)  mine,  N.  C 52 

Orange  county,  N.   C,  occurrence  of  gold 

in    45 

Orange  county,  Va.,  mines  in 73 

Orange  Grove  mine,  Va 73 

Ore  concentration   36 

Ore  zones  of  South  Mt.  gold  belt 19,  20 

Page   mine,    Va 75 

Palmetto  mine,  S.  C 77 

Parish  mine,  N.   C 47 

Parker  (or  Magazine)  Branch  placer  mine, 

Burke  county,  N.   C 101 

Parker  mine,    Cherokee  county,   N.   C....26 

Parker  mine,  Stanly  county,  N.   C 54 

Parks  mine,  Ga 81 

Parks  mine,  N.  C 63 

Parson  mill  35 

Patrick  county,  Va.,  occurrence  of  gold  in.76 

Paulding  county,   Ga.,  mines  in 82 

Pax  Hill  mine,  N.  C 68 

Payne   mine,   Va 75 

Pear  Tree  Hill  mine,  N.  C 52 

Person  county,  N.   C,   occurrence  of  gold 

in    45 

Phelps  process   39 

Phifer  mine,  N.   C 63 

Phillips,   W.   B.,    cited 13,  27,  62,  90,  139 

Phoenix  mine,   N.   C 37,  60-62 

Pickens  county,   S.  C,  occurrence  of  gold 
in    


77 

Piedmont  mine,   Ga 81 

Pilot    mountain,    N.    C,    hydraulic   mining 

at     32 

Pilot  Mountain  ore  zone 19,  20 

Pine  Mountain  mine,  Ga 82 

Pinetucky   mine,   Ala 87,  88 

Pioneer  Mills  mine,  N.   C 61,  62 

Placer  mines,   described 91-115 

Placer   mining,    possibilities   of   discussed, 

148,  149 

Plattner  chlorination   process 38,  62 

Plattsburg   (or    Chattahoochee)   Gold  Min- 
ing and  Milling  Co.'s  mines,  Ga 79 

Polk  county,  N.  C,  petty  mining  in 69 

Polk  county,  Tenn.,  occurrence  of  gold  in. 90 


PAGE 

Portis  mine,   N.  C 4M.  45 

Potosi  mine,    Ga 80 

Powhatan  Land  and  Mining  Co..    referred 

to    72 

Preacher  mine,  Ga 80 

!    Preface    9,  10 

;    Price  (Golden  Eagle)   mine,   Ala 87 

j    Prince  Edward  county,  Va.,  occurrence  of 

gold    in    76 

Pritchard   mine,    Ala 86 

Proceedings  of  American  Philosophical  So- 
ciety,  referred  to 27 

I    Pullian   mine,    Va 73 

Pyrite  mines  of  Louisa  county,  Va. . .  .73.  74 

!    Quaker  City  mine,  N.   C ' 60.  62 

j    Rabun  county,  Ga.,  mines  in 78 

|    Ralston  mine,   Ga 80 

|    Randleman  mine,   N.    C 57 

Randolph  county,   Ala.,  mines  in 87-89 

!    Randolph  county,  N.  C,  mines  in 46-47 

I    Randolph   (Earnhardt)  vein,   Gold   Hill.   N. 

C 34.  58.  59 

!    Rappahannock   Gold   Mining   Co.,   referred 

to     72 

I    Rattlesnake  mine,  Va 72 

I    Ray  mine,  N.  C 64 

Red  Hill  mine  pit  (Haile  mine). 127.  129,  132 

|    Reed   mine,    N.    C 60.  61 

I    Reimer  mine,  N  C 36,  38,  57,  117-121 

Reynolds  mine,  N.  C 52 

Reynolds  vein.   Ga 32 

Rhyne  mine,   N.   C 66 

Richardville  mine,  Va 72 

Riddle  mine,   Ala. 90 

Riggon  Hill  mine,  N.   C 53 

Ringel,   C,  referred  to 37 

Roasting  processes    36,  37 

Roasting  process  at  Franklin  mine..  124.  125 

Haile  mine   137-139 

Reimer  mine   119 

Robinson  mine,  N.  C 66 

Rock-decomposition    11 

Rockers,   descriptions  of 30,  94.  95 

Rocky  River  mine,  N.  C 60,  61 

Rogers,  ^Ym.  B.,  referred  to 13 

Rose,    T.  K.,   referred  to 142 

Roseman   mine,    N.    C 5 1 

Rowan  county,  N.  C,  mines  in 57-60 

Roy  Stone  method  of  dredging  and  gravel- 
elevating    - 32,  106 

Royal   (Camille)   mine 3S,  S2,  83 

Rudisil  mine,   N.   C 63,  64 

Russell   mine,   N.    C 17,  3S,  52.  53 

Rutherford  county,   N.   G,   mines  in.  .68.  69 
Safford's    Geology   of   Tennessee,    referred 

to    27 

Salisbury  Supply  Co.,  test  mill lol 

Sam  Beattie  mine,  N.  C 66 

Sam  Christian  Company,  referred  to 52 

Sam  Christian  mine,  N.  C 52 

Sand-pump,   used  as  gravel  elevator 102 

Saprolite,  definition  of 

Saunders   mine,   N.    C 


,53 


INDEX. 


163 


PAGE 

Sawnee  Mountain  mine,   Ga 81 

Sawyer  (Harrison)  mine,  Mel 71 

Sawyer  mine.   N.    0 38,  47 

Seott  Hill  mine,  N.  C 68 

Settles    mine,    Ga 81 

Shelby  mine,  Ga 81 

Shields   mine,   N.    C 57 

Silliman,   Prof.   B.,   cited 20,  75 

Siloam    mine.    Ga 80 

Silver  ores   30,  48-51,  58 

Silver  and  Gold  production,    statistics   of, 

40-42 

Silver  Creek  placer  mines,  N.  C 07 

Silver  Hill  (Washington)   mine,   N.    C, 

18,  37,  30,  40,  48,  49 
Silver  Valley  mine,  N.  C...18,  30,  40,  40-51 

Simmons  mine,   Ga 81 

Simpson  mine,   N.    C 64 

Singleton   mine,    Ga 21,  23,  35,  80 

Sixes   mine,    Ga 82 

Skip  used  at  Haile  mine 134,  135 

Slack  mine,  N.   C 47 

Slate  Hill  mine,   Va 14,  74 

Sluice-box,  descriptions  of.... 30,  03,  04,  100 

Smart   mine,   N.    0 63 

Smelting  processes   ..30,  40,  50,  51,  153,  154 

Smelting  process  at  the  Conrad  Hill  mine. 51 

Silver  Hill  mine... 30,  40 

Silver  Valley  mine. 40,  50 

Smith,  Mrs.  J.  B.,  referred  to 85 

Smith    mine,    Ga 78 

Smith    (Welborn)   mine,    Davidson    county, 

N.    C 51 

Smith  mine,  Gaston  county,  N.  C 66 

Smith  and  Palmer  mine,  N.  C 63,  64 

South   Carolina,   distribution  of  mines   in, 

76-7S 
early  discovery  of  gold.. 26 
production    of    gold    and 
silver  in   ...  .40,   42 
South  Carolina  Geological  Survey,  publica- 
tions referred  to 13,  32,  37,  41,  77,  126 

South    Carolina    State    Board    of   Agricul- 
ture,  publication    referred   to 76 

South     Mountain     gold     belt,     elescription 

of 18,  20 

in  N.  C 68-70 

in  S.  C 77-78 

ore  zones  of 10,  20 

mines  in,   68,   70,   77,   78 
Southern   Appalachian   gold   belt,    descrip- 
tion  of 11-25 

divisions  of  13 

geology   of,   11-25 

Southern  Belle  mine,  N.   C 57 

Southern  States  Exploration  and  Financial 

Syndicate,  L't'd.,  referreel  to 82 

Spanish  Oak  Gap  mine,  N.   C 52 

Spartanburg  county,   S.  C,  mines  in.. 77,  78 

Spence   roasting   furnace 130 

Spillsbury,  E.   G.,  referred  to 30,  120 

Spottsylvania  county,  Va.,  mines  in.  .72,  73 


PAGE 

St.  Catherine  mine,  >'.   C 63,  64 

St.  George  (Dean)  mine.   Ga 70 

Stafforel  county,   Va.,   mines   in 72 

Stamp-mill,   history  of   33,  35 

the    Hall    pattern    elescribed, 

110-113 
the    Mecklenburg  Iron    Works 
pattern  elescribed   ....110,  120 

Standard  vein.  Gold  Hill,  N.  C 58 

Stanley    mine,    Ga 80 

Stanly  county,  N.   C,   mines  in 54-56 

Statistics  of  gold  and  silver  production. 40-42 
Statistics  of  South  Carolina  (Mills),  cited. 26 

Steel  mine,  N.  C 53 

Stephen  Wilson  mine,  N.  C 63 

Stewart   mine,    N.    Co 63 

Stockton,  Commodore,  referred  to.... 30,  145 

Story   mine,    Ala 00 

Strickland  mine,    Ga 82 

Stringer-lead,    defined    23 

Surface  Hill  mine,   N.   C 64 

Sutherland  mine,  Ala 86,  87 

Swain  county,  N.  C,  placer  mining  in... 70 

Swedish  chlorination  process 153 

Table  of  contents   3-5 

Tables    showing    production    of    gold    and 

silver    40-42 

Tagus    mine,    Va 75 

Talc-schist,  incorrect  use  of  term 15 

Talladega  county,  Ala.,  mines  in 00 

Tallapoosa  county,  Ala.,  occurrence  of  gold 

in    00 

Tanyard  placer,  Brewer  mine .145 

Tatham  mine,  Ga 85 

Taylor  mine,  N.   C 43 

Taylor  and  Trotter  mine,  N.  C 63 

Tellurium,  occurrence  of  in  ores,  18,  24,  52,  67 

Tellurium   mine,    Va 32,  35,  75 

Tennessee,  distribution  of  mines  in 00 

early  discovery  of  gold  in.... 27 
production   of   gold    and   silver 

in 40,  42 

Terrell  mine,  Ala. . .  , 00 

Thies,  A,  referred  to.  10,  37,  61,  83,  125,  120, 

130 

Thies   chlorination   process 37,  153 

Thomas  mine,   N.    C 43 

Thompson    mine,    Ga 22,  70 

Thompson   mine,    S.    C. 78 

Thomson  mine,   S.   C 77 

Thurston,   Scott,    referred  to 7.'. 

Tiger  river  placer  mines,   S.   C 7S 

Tinder  Flats  placer  mine,   Va 20,  74 

Tom's  Creek  mine,   N.   C 52 

Tonton  mine,  Ga 70 

Towne  county,  Ga.,  mines  in S4 

Transactions    of   American    Institute   Min- 
ing Engineers,  referred  to 0,  10,  14,  24 

31,    32,    35,    30,    62,    71,    102,    106,    120,    130 

Trautman  vein,   Gold  Hill,   N.   C 58,  50 

Treatment  of  freemilling  ores.:32-36,  110-116 
Treatment  of  sulphuret  ores.. 36-40,  117-147 
Tredinick  mine,    X.    C 64 


164 


INDEX. 


•  i 


PAGE 

Triumph    concentrating    machine 36 

Tucker   (California)   mine,   N.    C...38,  61,  62 

Tuomey,    M.,    cited 30,  77 

Turkey  Heaven  mining'  district,   Ala.. 86,  87 

Turkey  Hill  mine,  Ga 80 

Twin  mine,   N.   C 45.  46 

Uharie  mine,  N.  C 47 

Ulrich  mines,  Ala 90 

Union  county,  N.  C,  mines  in 62,  63 

Union  county,  S.  C,  mines  in 77 

United     States     assay     offices,     statistics 

from    40-42 

United  States  census  report,  referred  to.. 42 
United   States  Geological  Survey,   publica- 
tions   referred    to.  11,  13,  18,  22.  23,  24,  26 
United     States     Mining     Co.,     report     of, 

cited    33,  72 

United     States     mint     bureau,      statistics 

from    40-42 

United    States   mint,    reports,    referred   to, 

26,  40-42 

Valdor   mine,    Ala 85 

Valley  river,  N.  C,  placer  mines 70 

Van  Dyke,   Dr.   M.   H.,   referred  to 31 

Vaucluse  mine,  Va 32.   34,   36,   30,   73 

Veins,   early  discovery  of 32 

Vein  mining,  early  records  of 32 

possibilities   of.    discussed, 

150-154 
Vein  Mountain  (Jamestown)  mine,  N.  C. .  31,   60 

Villa  Rica  mining  district,  Ga 82 

Virginia,  distribution  of  mines  in 71-76 

early  discovery  of  gold  in 26 

production     of    gold     and     silver 

in    40,  42 

Virginia  gold  belt,   description  of 13,  14 

mines  in   71-76 

Virginia,  Notes  on  (Jefferson),   cited 26 

Virginias,  the  geology  of  the,  referred  to.  13 
Volcanic  rocks  of  the  Carolina  gold  belt..  16 

Walker-Carter  roasting  furnace 39 

Wallace  mine,   S.   C 77 

Walters  and  Gardner  mine,  Va 76 

Walton   mine,   Va 74 

Walton  Mining  Co.,  report  of.  referred  to. 29 

Warne  mine,   N.    C 70,  84 

Warren  county,   Ga.,  mines  in 84,  85 

Warren  county,  N.  C,  mines  in 43 

Warren  mine,   Ga 85 

Warren  Hill  mine,  Va 14,  74 

Washington  (Bonnie  Belle)  mine.  X.  C 63 

Washington  (Silver  Hill)  mine,  X.  C.  .48,  49 
Watauga  county,  X.  C,  auriferous  galena 
ores 70 


PAGE 

Water-power,  application  of  to  mining.  .  .154 

at  the  Chestatee  mine 101 

Crawford  mine.  .92.  93 

Hedwig   mine 115 

Kin   Mori   mine 81 

Loud  mine   79 

Mills  mines,  95-98,  101 

Old  Field  mine 84 

Parker  mine   55 

Sam  Christian  mine  52 
Wolfe  Creek  mines. 78 

Yonah    mine 79 

Water-supply     of      the      Dahlonega      dis- 
trict  108,   109 

South  Mountain  district 95 

Welborn  (Smith)  mine,  N.   C 51 

Welborn  Hill  mine,    Ga 84 

West  mine,  S.  C 77 

West  Springs  mine,  S.  C 78 

Whatley,  E.  T..   referred  to 70 

White  county,  Ga.,  mines  in .78,  79 

Whitehall    mine.    Va 73 

Widenhouse  mine,  N.  C 60 

Wilkes,   Jno.,  referred  to 10.  119 

Wilkes  county,  Ga.,  mines  in 84,  85 

Wilkes    county.    N.    C,    auriferous    galena 

ores  in    70 

Wilkes  mine.  Ga S3 

Wilkinson  mine.  Ga 82 

Wilkinson  mine,   X    C 31 

Williams  mine.  Ga 85 

Williams  mine.   S.   C 77 

Wilson  mine,   S.  C 77 

Wilson-Kindley   mine,   N.    C 47 

Wimpy,  A.   G..  referred  to 29 

Winningham  mine,   N.   C 47 

Winslow  mine,  X  C 47 

Wiswell  mill  35 

Witheroods,   Jno.,   referred  to 26 

Wolfe  and  Tiger  Mining  Co..  referred  to..7S 

Wolfe  Creek  placer  mines,  S.  C 7S 

Woodward  mine.   Ga 80 

Worley   mine,    Ga 82 

Worth  mine,   X.    C. 52 

Wycoff   mine,    Va 72 

Yadkin  Chlorination  Works,  referred  to.  117 

Yadkin   county.  X.   C.   mines  in 6S 

Yadkin  mine,  X.  C 57 

Yonah  Land  and  Mining  Co.,   mines.   Ga.. 

79.  150 

Yonah  Peak,  Ga..  granite  at 21 

York  county.   S.  C.  mines  in 77 

Yorkville    mines.    Ga S2 


i 


164 


INDEX. 


'  k 


Triumph    concentrating    machine 36 

Tucker  (California)   mine,   N.    C...38.  61,  62 

Tuomey,    M.,    cited 30,  77 

Turkey  Heaven  mining  district,  Ala.. 86,  87 

Turkey  Hill  mine,  Ga 80 

Twin  mine,   N.  C 45.  46 

Uharie  mine,  N.   C 47 

Ulrich  mines,  Ala 90 

Union  county,  N.  C,  mines  in 62,  63 

Union  county,  S.  C,  mines  in 77 

United     States     assay     offices,     statistics 

from     40-42 

United  States  census  report,  referred  to.. 42 
United   States  Geological  Survey,   publica- 
tions   referred    to.  11,  13,  18,  22.  23,  24,  26 
United     States     Mining     Co.,     report     of, 

cited 33,  72 

United     States     mint     bureau,      statistics 

from    40-42 

United   States   mint,   reports,   referred   to, 

26,  40-42 

Valdor   mine,    Ala 85 

Valley  river,  N.  C,  placer  mines 70 

Van  Dyke,   Dr.   M.   H.,   referred  to 31 

Vaucluse  mine,  Va 32,   34,   36,   39,   73 

Veins,    early   discovery   of 32 

Vein  mining,  early  records  of 32 

possibilities   of,    discussed, 

150-154 
Vein  Mountain  (Jamestown)  mine,  N.  C. .  31,   69 

Villa  Rica  mining  district,  Ga 82 

Virginia,  distribution  of  mines  in 71-76 

early  discovery  of  gold  in 26 

production     of    gold     and     silver 

in    40,  42 

Virginia  gold  belt,   description  of 13,  14 

mines  in   71-76 

Virginia,  Notes  on  (Jefferson),   cited 26 

Virginias,  the  geology  of  the,  referred  to.  13 
Volcanic  rocks  of  the  Carolina  gold  belt..  16 

Walker-Carter  roasting  furnace 39 

Wallace  mine,   S.   C 77 

Walters  and  Gardner  mine,  Va 76 

Walton   mine,   Va 74 

Walton  Mining  Co.,  report  of,  referred  to. 29 

Warne  mine,   N.    C 70,  84 

AVarren  county,   Ga.,  mines  in 84,  85 

Warren  county,  N.  C,  mines  in 43 

Warren  mine,   Ga , 85 

Warren  Hill  mine,  Va 14,  74 

Washington  (Bonnie  Belle)  mine.  N.  C....63 
Washington  (Silver  Hill)  mine,  N.   C.  .48,  49 
Watauga  county,  N.  C,  auriferous  galena 
ores 70 


PAGE 

Water-power,  application  of  to  mining.  ..154 

at  the  Chestatee  mine....  101 

Crawford  mine.  .92,  93 

Hedwig   mine 115 

Kin   Mori   mine 81 

Loud  mine   79 

Mills  mines,  95-98,  101 

Old  Field  mine 84 

Parker  mine   55 

Sam  Christian  mine  52 
Wolfe   Creek  mines. 78 

Yonah    mine 79 

Water-supply      of      the      Dahlonega      dis- 
trict  108,   109 

South  Mountain  district.  ..  .95 

Welborn  (Smith)  mine,  N.   C 51 

Welborn  Hill  mine.    Ga 84 

West  mine,  S.  C 77 

West  Springs  mine,  S.  C 78 

Whatley,  E.  T..   referred  to 79 

White  county,  Ga.,  mines  in '. .  .78,  79 

Whitehall    mine.    Va 73 

Widenhouse  mine.  N.   C 60 

Wilkes,   Jno.,  referred  to 10.  119 

Wilkes  county,  Ga.,  mines  in S4,  85 

Wilkes    county.    N.    C,    auriferous    galena 

ores  in    70 

Wilkes  mine.  Ga 83 

Wilkinson  mine.   Ga 82 

Wilkinson   mine,    N.    C 31 

Williams  mine,  Ga 85 

Williams  mine.   S.   C 77 

Wilson  mine,    S.   C 77 

Wilson-Kindley   mine,   N.   C 47 

Wimpy.  A.   G.,  referred  to 29 

Winningham  mine,   N.   C 47 

Winslow  mine,  X.   C 47 

Wiswell  mill   35 

Witheroods,   Jno.,   referred  to 26 

Wolfe  and  Tiger  Mining  Co.,  referred  to..7S 

Wolfe  Creek  placer  mines,   S.  C 7S 

Woodward  mine.   Ga SO 

Worley   mine,    Ga S2 

Worth  mine,  N.    C .  = 52 

Wycoff   mine.    Va 72 

Yadkin  Chlorination  Works,  referred  to.  117 

Yadkin   county.  X.   C.   mines  in 68 

Yadkin  mine,  N,  C 57 

Yonah  Land  and  Mining  Co.,   mines.   Ga.. 

79.  150 

Yonah  Peak.  Ga..  granite  at 21 

York  county,   S.   C.  mines  in 77 

Yorkville    mines.    Ga S2 


K3£ .!    km 


BULLETIN  11  PLATE    1 


8T30' 


fc  IW' 


>v 


■  ^   V     ^*-4&atl 


Yir^L^ 


NORTH  CAROLINA  GEOLOGICAL  SURVEY 
J -A.  Holmes,  State  Geologist 

GEOLOGIC    SKETCH     MAP 

OF 


ri 


estern  North  Carolina 

Showing  Corundum  Localities  and  the 
distribution  of  Peridoti  tes  and  Related  Rocks. 

BY 

J.Volney  Lewis . 
1895. 
Scale 


Boundaries  of  the  Ocoee  formation  have  been  supplied  by 
Mr.  Arthur  Keith  of  the  United  States  Geological  Survey. 


\ 


NORTH  CAROLINA  GEOLOGICAL   SURVEY, 

J.  A.  HOLMES,  STATE  GEOLOGIST. 


BULLETIN  No.  11. 


CORUNDUM  AND  THE  BASIC  MAGNESIAN 

ROCKS  OF  WESTERN  NORTH 

CAROLINA. 


BY 

JOSEPH  VOIvNEY  LEWIS, 

Assistant  Geologist. 


MAP  CORRECTIONS. 

Through  some  misunderstanding  several  small  errors  have  been  made 
in  the  geological  boundaries  on  the  western  portion  of  this  map,  chiefly  in 
Unicoi,  Cocke  and  Monroe  counties,  Tennessee,  and  in  Madison  and 
Mitchell  counties  in  North  Carolina.  The  errors  were  discovered  too 
late  to  be  corrected  in  this  edition.  Later  work  lias  also  shown  that  the 
Ocoee  rocks  should  be  made  to  extend  across  the  area  left  uncolored  in 
Cherokee  county  (N.  C),  and  Polk  county  (Tenn.),  and  that  the  uncolored 
area  in  Wilkes,  Alleghany  and  Ashe  counties  should  be  colored  for 
"gneisses  and  granite. "  All  needed  corrections  will  be  made  in  a  future 
edition  of  this  map,  which  it  is  expected  will  be  published  at  an  early  date. 


C\ 


/ 


*rrp. 


•  i 


CONTENTS. 


PAGE. 

Letter  of  Transmittal 7 

1.  Introduction 9 

2.  Geologic  Sketch  of  the  Corundum  Region 11 

3.  The  Peridotites  and  Associated  Massive  Rocks 15 

(1.)  The  Peridotites .' 15 

a.  Dunite 17 

b.  Harzburgite 23 

c.  Amphibole-picrite „  23 

d.  Forellenstein 24 

(2.)  The  Pyroxenites 25 

a.  Enstatite  rock 25 

b.  Websterite  27 

(3.)  Ainphibolites j 28 

4.  Associated  Secondary  and  Schistose  Rocks 30 

(1.)  Massive 30 

a.  Serpentine 30 

(2.)  Schistose 32 

a.  Talc  schist,  Soapstone 32 

b.  Chlorite  schist 33 

5.  Distribution  of  the  Peridotites  and  Associated  Rocks 33 

(1.)  In  the  Appalachian  belt 33 

(2.)  In  North  Carolina 34 

a.  Clay  county . 35 

b.  Macon  county 36 

c.  Jackson  county. 37 

d.  Transylvania  county 39 

e.  Haywood  county 40 

/.  Buncombe  county 40 

g.  Madison  county 41 

h.  Yancey  county 43 

i.  Mitchell  county 44 

j.  Watauga  county 45 

7c.  Ashe  county 46 

I.  Alleghany  county 47 

6.  Corundum 48 

(1.)  Character  and  Varieties 48 

(2.)  Uses  of  Corundum 51 

(3.)  North  Carolina  Corundum = 51 

(4.)  Modes  of  Occurrence  of  Corundum 54 

a.  Associated  with  peridotite. 55 

b.  In  chlorite  schist 57 

c.  In  amphibolite 58 

d.  In  dunite 00 

e.  In  gneiss 01 

/.  In  gravel  deposits 02 


M 


CONTENTS. 


7. 


8. 


PAOE. 

(5.)  Distribution  of  corundum 63 

a.  In  the  Appalachian  belt 63 

Alabama 64 

Georgia 64 

South  Carolina 64 

North  Carolina 64 

Virginia 65 

Maryland 65 

Pennsylvania 65 

New  Jersey 65 

New  York 66 

Connecticut 66 

Massachusetts 66 

b.  In  North  Carolina 67 

Clay  county 67 

Macon  county 69 

Jackson  county 70 

Transylvania  county 72 

Haywood  county 73 

Buncombe  county 73 

Madison  county 74 

Yancey  county 75 

Mitchell  county 75 

Iredell  and  Alexander  counties 76 

Burke  and  Cleveland  counties 77 

Gaston  county 77 

Guilford  county 77 

Other  localities 78 

(6.)  Methods  of  Prospecting  for  Corundum 78 

(7.)  Mining  and  Cleaning  methods 81 

Historical  Sketch  of  Corundum  Mining-  in  America 86 

(1.)  Discoveries  and  early  Developments 87 

(2.)  North  Carolina  Corundum  mines 89 

a.  The  Behr  mine,  Clay  county 91 

b.  The  Buck  creek  (Cullakanee)  mine,  Clay  county 91 

c.  The  Corundum  Hill  (Cullasaja)  mine,  Macon  county 92 

d.  The  Sapphire  (Hogback)  mine,  Jackson  county 94 

e.  The  Carter  mine,  Madison  county 94 

/.  The  Acme  mine,  Sfatesville,  Iredell  county 95 

Other  Economic  Minerals  of  the  Corundum  Belt 96 

(1.)  Chromite,  or  chromic  iron 96 

(2.)  Asbestos 96 

(3.)  Nickel-bearing  minerals. 97 

(4.)  Serpenl ine 97 

Literature  on  the  Corundum  Belt 99 

Index 103 


\ 


ILLUSTRATIONS, 


Plate  I.  Geologic  sketch  map  of  western  North  Carolina Frontispiece. 

II.  Sketch  map  of  the  Appalachian  crystalline  belt 32 

III.  Map  of  the  Buck  creek  peridotite  area,  Clay  county.. 34 

IV.  Map  of  Corundum  Hill,  Macon  county 36 

V.  Map  of  the  Webster  peridotite  area,  Jackson  county 38 

VI.  Photomicrographs  of  thin  sections  of  dunite 102 

FIGURE  1.  Corundum  crystal,  showing  rhombohedral  parting 49 

2.  Corundum  crystal,  showing  basal  parting 49 

3.  Corundum  crystal  from  Egypt  mine,  Yancey  county 49 

4.  Corundum-bearing  zone  in  amphibolite,  Iredell  county 59 

5.  Corundum  crystal  in  dunite,  Egypt  mine,  Yancey  county..  60 

6.  Diagram  of  corundum-bearing  zone,  Corundum  Hill 93 

7.  Corundum  crystal  from  Ivy  river,  Madison  county 74 

8.  Corundum  wrapped  iu  margarite,  Iredell  county , 76-. 


/ 


LETTEK  OF  TRANSMITTAL. 


Raleigh,  N.  C,  December  1st,  1895. 

To  His  Excellency  Hon.  Elias  Carr, 

Governor  of  North  Carolina. 

Sir: — I  beg  to  submit  for  publication  as  Bulletin  11  of  the 
Geological  Survey,  a  preliminary  report  on  Corundum  and  the 
associated  basic  Magnesian  Rocks  in  North  Carolina,  by  Mr.  J.  Y. 
Lewis.  The  larger  part  of  the  corundum  now  produced  in  the 
United  States  is  mined  in  North  Carolina,  and  the  increasing 
demand  for  information  on  this  subject  has  led  to  the  preparation 
of  this  paper.  It  is  hoped  that  a  more  elaborate  final  report  on 
the  subject  can  be  prepared  by  the  close  of  another  year. 
With  great  respect,  I  have  the  honor  to  be,  sir, 

Yours  obediently, 

J.  A.  Holmes, 

State  Geologist. 


CORUNDUM  AND  THE  BASIC  MAGNESIAN 

ROCKS  IN  WESTERN  NORTH 

CAROLINA. 


BY 


J.  VOLNEY  LEWIS. 


■ 


1 


CORUNDUM  AND  THE  BASIC  MAGNESIAN  ROCKS  IN 
WESTERN  NORTH  CAROLINA. 


By  J.  Volney  Lewis. 


i.  INTRODUCTION. 

The  present  incomplete  report  is  issued  for  the  purpose  of  pre- 
senting the  field  results  obtained  chiefly  during  the  summer  months 
of  1893  and  1894. 

To  the  fact  that  it  is  mainly  a  report  of  field  observations  is  due, 
to  a  great  extent,  its  incompleteness;  and  I  would  urge  this  con- 
sideration as  an  apology  for  certain  vagaries  of  mineralogic  termi- 
nology in  the  following  pages,  and  for  many  unsatisfactory  points 
in  geologic  and  petrographic  descriptions.  As  far  as  possible,  I 
have  confined  myself  to  a  simple  presentation  of  facts  thus  far 
determined,  and  the  more  theoretical  discussions  have  been 
avoided. 

In  the  beginning  of  the  field  season  of  1893,  a  rapid  reconnais- 
sance of  the  region  under  consideration  was  made  with  the  late  Dr. 
George  H.  Williams,  of  Johns  Hopkins  University ;  and  a  portion 
of  the  laboratory  work  and  the  field  studies  for  both  this  and  the 
succeeding  seasons  were  prosecuted,  to  a  great  extent,  under  his 
guidance  and  general  supervision.  Specimens  were  collected  from 
all  portions  of  the  region,  and  by  the  courtesy  and  cooperation  of 
the  Director  of  the  United  States  Geological  Survey,  I  have 
begun  the  microscopic  study  of  this  material  in  the  Survey  laborato- 
ries, at  Washington.  A  more  thorough  report  on  the  corundum- 
bearing  rocks,  embodying  the  results  of  this  work,  will  be  pub- 
lished as  soon  as  practicable. 

One  acquainted  with  the  methods  and  aims  of  geology,  or  of  any 
natural  science,  needs  no  argument  to  point  oat  the  necessity  of 


10 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


thorough  detailed  work  for  the  understanding  of  any  problem  in 
Nature,  whether  of  immediate  economic  importance  or  only  of 
scientific  interest.  Thus  far  all  that  is  known  of  the  extent  and 
value  of  our  corundum  deposits  has  been  derived  from  experience  ; 
that  is  to  say,  from  actual  prospecting  and  mining.  Studies  of 
considerable  iuterestand  value  in  the  corundum  regions  have  been 
made  by  Chatard,  Julien,  Shepard,  Genth  and  others,  but  these 
have  been  confined  chiefly  to  local  occurrences  and  special  problems, 
and  no  attempt  has  been  made  to  cover  the  whole  field ;  conse- 
quently, the  various  theories  that  have  been  advanced  in  regard  to 
the  origin  of  corundum  and  its  associated  rocks  have  left  entirely 
out  of  consideration  much  evidence  which  only  a  careful  survey  of 
the  whole  area  could  furnish. 

I  can  scarcely  hope,  by  the  work  in  hand,  to  furnish  a  final  or 
even  a  very  satisfactory  answer  to  the  question  of  origin ;  for 
such  problems,  in  areas  of  great  disturbance  and  so  thoroughly 
metamorphosed  as  the  one  under  consideration,  do  not  readily 
yield  clear  results ;  but  it  is  hoped  that  even  the  facts  recorded 
here  may  add  something  to  the  small  sum  of  our  knowledge  of 
these  interesting  formations,  and  that  thereby  a  somewhat  clearer 
understanding  of  their  geologic  relations  may  be  attained. 

From  the  standpoint  of  the  prospector,  miner,  or  land-owner, 
whose  interest  in  such  matters  is  eminently  practical  and  whose 
geologic  training  is  entirely  the  result  of  work  and  observations 
in  the  mines  themselves,  it  is  hoped  that  this  presentation  of  facts 
may  be  found  useful,  and  that  the  mining  interests  of  every  section 
may  be  advanced  by  a  study  of  conditions  existing  in  other  por- 
tions of  the  field.  In  fact,  this  method  of  comparison  has  been 
found  the  only  practical  guide  in  the  search  for  new  localities  or 
in  the  development  of  deposits  already  known.  If  the  rocks  and 
associated  minerals  of  a  given  locality  are  the  same  as  found  in  a 
corundum  mine,  the  prospector  goes  to  work  on  the  hypothesis  that 
the  occurrence  there  of  corundum  itself  is  entirely  probable. 
While  characteristic  differences  are  everywhere  observed  between 
mines,  even  in  the  same  immediate  neighborhood,  yet  experience 
has  shown  that  the  conditions  for  the  occurrence  of  corundum  are 
practically   the  same   throughout  the  region.      The  few  important 


GEOLOGIC    SKETCH    OF    THE    CORUNDUM    REGION.  11 

exceptions  to  this  rule  are  noted  further  on  in  describing  the 
modes  of  occurrence. 

For  the  reasons  suggested,  then,  it  has  been  thought  advisable 
to  publish  the  facts  gathered  in  the  field,  along  with  some  general 
observations  on  the  geology  of  the  region  and  the  characteristics  of 
the  corundum-bearing  rocks,  rather  than  hold  these  for  the  appear- 
ance of  the  final  report.  A  knowledge  of  the  facts  cannot  but 
advance  the  interests  of  legitimate  mining,  as  well  as  prevent  such 
waste  of  time  and  money  as  may  sometimes  be  observed  in  western 
North  Carolina. 

At  the  present  writing,  the  only  active  corundum  mining  in  the 
world  is  in  this  State,  and,  with  the  important  exception  of 
Georgia,  North  Carolina  has  supplied  the  only  corundum  on  the 
market  since  the  beginning  of  the  industry  more  than  twenty  years 
ago.  Besides  regular  mining,  much  work  has  been  done  in  explor- 
ing and  prospecting,  and  considerable  investments  have  recently 
been  made  with  a  view  to  engaging  in  active  mining  at  an  early 
date.  Explorations  have  never  been  more  actively  prosecuted  and 
it  is  not  unlikely  that  production  .will  be  largely  increased  in  the 
near  future  by  the  opening  of  new  mines.  That  there  is  abundant 
demand  for  such  increase  is  shown  by  the  fact  that,  in  addition  to 
the  available  corundum,  there  are  annually  imported  for  consump- 
tion in  the  United  States  from  3,000  to  5,000  tons  of  emery,  which 
is  practically  the  only  mineral  product  that  competes  with  corun- 
dum in  the  market. 

The  combination  of  circumstances  favorable  to  mining  and 
milling  operations  in  North  Carolina — the  equable  climate  and 
the  almost  universal  presence  of  water-power — together  with  the 
great  superiority  of  corundum  as  an  abrasive,  combine  to  place 
these  formations  among  the  important  resources  of  the  State. 

2.  GEOLOGIC  SKETCH   OF  THE    CORUNDUM   REGION. 

From  the  accompanying  map  it  will  be  seen  that  what  we  may 
term  the  Corundum  belt  in  North  Carolina  is  confined  to  a  broad 
strip  of  gneisses  lying  chiefly  west  of  the  Blue  Ridge  and  extend- 
ing   northwestward    from   the   Georgia    boundary   through    Clay, 


12 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


Macon,  Transylvania,  Jackson,  Haywood,  Buncombe,  Madison, 
and  Yancey  counties,  while  the  peridotites  with  their  character- 
istic chromium-  and  nickel-bearing  minerals,  asbestos,  etc.,  extend 
the  belt  through  Mitchell,  Watauga,  Ashe,  and  Alleghany  coun- 
ties to  the  Virginia  line. 

This  belt  is  but  a  portion  of  the  greater  belt  of  crystalline  rocks 
which  is  coextensive  with  the  Appalachian  mountain  system  (see 
plate  II),  and  which,  on  account  of  its  complex  and  highly  crystal- 
line character,  is  generally  considered  to  be  of  Archean  age.  The 
southern  extremity  of  this  belt  disappears  under  the  younger 
formations  in  central  Alabama.  Its  principal  constituent  is  gneiss, 
often,  through  higher  development  of  lamination,  passing  into 
schists,  and  including  frequent  masses  of  granitic  and  other  dis- 
tinctively igneous  rocks. 

These  gneisses  have  been  usually  considered  to  be,  in  great  part, 
sedimentary  rocks  that  have  lost  their  original  clastic  characteris- 
tics, with  the  possible  exception  in  some  cases  of  bedding,  in  the 
great  earth-movements  and  other  metamorphosing  agencies  in 
which  they  have  been  involved.  Some  of  them,  however,  are 
certainly  granites  or  other  massive  rocks  that  have  been  sheared 
or  squeezed  by  the  same  agencies — transitions  from  the  massive  to 
the  laminated  forms  being  often  easily  observed  and,  in  fact,  almost 
universally  present  about  the  borders  of  the  massive  rocks  of  the 
region. 

When  these  changes  have  affected  the  whole  of  such  an  igneous 
mass,  it  is  obvious  that  a  rock  will  result  that  will  often  be  difficult 
and  sometimes  impossible  to  distinguish,  in  the  field,  from  a  meta- 
morphosed sediment  of  similar  composition.  As  yet  the  geology 
of  this  area  is  not  sufficiently  known  to  map  these  varieties 
separately;  though  such  distinctions  are  highly  desirable  in  con- 
sidering the  questions  of  origin  of  some  of  the  massive  rocks  and 
their  relations  to  the  prevalent  structural  types  of  the  region. 

By  the  earlier  geologists,  the  lamination  of  the  gneiss  was  con- 
sidered true  bedding,  and  their  attempts  to  interpret  the  structure 
of  the  region  were  based  on  this  misconception.  It  is  well  known 
that  lamination  is  often  developed  where  no  such  original  struc- 
ture existed,  as  in  the  sheared  massive  rocks  alluded  to  above.     It 


GEOLOGIC    SKETCH    OF    THE    CORUNDUM    REGION.  13 

is  also  known  that  such  structure  produced  by  movement  in  the 
mass  of  the  rock  may,  and  usually  does,  obliterate  whatever  origi- 
nal structure  may  have  been  present ;  so  that  a  sedimentary  rock 
thus  mechanically  laminated  and  at  the  same  time  thoroughly  crys- 
tallized would  no  longer  show  its  original  stratification.  The  new 
structural  planes  might  correspond  in  certain  cases  with  bedding, 
but  often  they  would  not ;  and  hence  the  strikes  and  dips  observed 
in  this  region  and  recorded  here,  being  those  of  lamination  planes, 
are  not  in  any  case  to  be  interpreted  as  true  strikes  and  dips. 

The  prevailing  strike  of  the  lamination  planes  in  the  gneiss  of 
western  North  Carolina  is  about  north  30°  east,  and  the  prevailing 
dip  is  at  a  high  angle  toward  the  southeast.  Yery  frequently 
local  variations  occur,  especially  in  the  dips,  and  often  the  preva- 
lent southeasterly  dip  will  become  vertical  and,  tipping  over,  will 
pass  into  a  northwesterly  dip  within  an  outcrop  of  only  a  few  feet. 
All  stages  occur  from  these  local  variations  in  dip  and  strike  to  the 
most  gnarled  and  contorted  forms  imaginable.  In  general,  the 
lamination  has  suffered  the  most  deformation  in  the  immediate 
vicinity  of  igneous  intrusions  ;  or  perhaps  the  statement  might  be 
reversed,  as  the  forces  that  produced  the  contortions  doubtless 
formed  simultaneously  the  fissures  into  which  the  massive  rocks 
were  injected. 

Constituting  a  small  proportion  of  this  belt,  as  regards  area,  are 
the  basic  magnesian  rocks,  chiefly  peridotites,  which  are  here 
specially  considered  in  their  relations  to  the  occurrence  of  corun- 
dum. These  occur  in  small  lenticular  masses  or  in  narrow  strips, 
rarely  exceeding  a  mile  or  two  in  length,  and,  so  far  as  I  am  aware? 
are  nowhere  intimately  associated  with  the  well  recognized 
igneous  rocks  of  the  granitic  type.  Contortions  are  observed, 
however,  in  the  adjacent  gneisses  similar  to  those  in  the  vicinity 
of  granites,  and  often  a  transition  to  mica-schist  gives  evidence  of 
an  unusual  amount  of  movement. 

The  magnesian  rocks,  too,  whether  peridotites  or  pyroxenites, 
have  always  a  sheath  of  schistose  talc  developed  about  their  bor- 
ders and,  in  the  corundum-bearing  region,  also  much  chlorite. 
Hence  there  is  never,  as  far  as  observed,  an  absolute  contact  be- 
tween these  massive  rocks  and  normal  irneiss. 


14  CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 

South  of  Virginia,  the  gneissic  belt  is  flanked  on  the  west  by  a 
broad  strip  of  partially  metamorphosed  but  generally  distinct  sedi- 
ments of  undetermined  geologic  age.  No  fossils  have  yet  been 
found  in  them  and  structures  are  greatly  confused  by  disturbances 
that  have  given  rise  to  the  Appalachian  system  of  mountains. 
Hence  their  relations  to  the  known  Paleozoic  rocks,  by  which,  in 
turn,  they  are  bordered  on  the  west,  is,  as  yet,  a  matter  of  contro- 
versy. These  beds  consist  of  a  lower  series  of  shales  and  lime- 
stones lying  uncomformably  on  the  gneisses,  and  followed  by  con- 
glomerates and  sandstones  above.  To  the  whole  formation  the 
name  Ocoee  has  been  given. 

Referring  again  to  the  map  (plate  I.),  it  will  be  seen  that  two  belts 
of  Ocoee  are  developed  in  western  North  Carolina  ;  the  one,  lying 
along  the  Tennessee  border,  a  broad  area  of  irregular  outline  and 
tapering  northward  to  a  point  just  south  of  Johnson  City,  Ten- 
nessee. Beyond  this  point,  as  far  as  the  boundary  has  been  traced 
northward,  the  paleozoic  formations  lie  directly  in  contact  with 
the  gneisses.  The  other  Ocoee  belt  forms  a  narrow  strip  lying 
about  forty  miles  further  east  in  its  southern  portion,  and  passing 
northwestward  from  the  upper  French  Broad  valley,  approximately 
in  the  direction  of  the  Blue  Ridge.  The  irregular  boundary  of  the 
western  area  brings  the  two  belts  within  twenty-five  miles  of  each 
other  in  places,  but  the  general  trend  of  them  both  is  the  same  as 
that  of  all  the  rocks  of  the  region,  and  corresponds  to  the  axes  of 
Appalachian  folding. 

The  eastern  belt  is  exceedingly  narrow  in  its  southern  portion, 
perhaps  even  narrower  in  places  than  indicated  on  the  map,  but 
it  broadens  northward  and  becomes  involved  in  extremely  com- 
plex folds  and  faults  in  Mitchell  and  Watauga  counties.  It  should 
be  stated  that,  north  of  the  36th  parallel,  as  the  detail  on  the  map 
would  indicate,  the  boundaries  of  this  belt  are  much  more  accu- 
rately determined  than  in  its  southern  extension.  East  of  this 
narrow  strip  of  Ocoee,  comes  a  broad  expanse  of  gneisses  and 
granites,  extending  beyond  Charlotte,  Salisbury,  and  Greensboro, 
and  forming  the  Piedmont  plateau  region  of  the  State. 

The  corundum-bearing  peridotite  belt  lies  wholly  within  the 
strip  of  gneiss  between   these  two  belts  of  Ocoee.      Almost  the 


THE    PERIDOTITES    AND    ASSOCIATED    MASSIVE    ROCKS 


15 


whole  width  of  this  strip  in  the  southwestern  portion  of  the  State 
is  thickly  dotted  with  small  peridotite  areas,  but  north  of 
Waynesville  they  become  more  irregular  and  scattering.  The 
manner  of  distribution  is  shown  on  the  map,  but,  for  the  sake  of 
clearness,  the  areal  proportions  are  there  often  necessarily  exag- 
gerated. This  is  especially  true  of  the  schistose  talc  and  chlorite 
rocks,  which  seldom  exceed  twenty  or  thirty  feet  in  width  of  out- 
crop. 

3.   THE  PERIDOTITES  AND  ASSOCIATED  MASSIVE  ROCKS. 


As  the  corundum  deposits  of  the  State  are  found  chiefly  in  con- 
nection with  these  rocks,  it  is  important,  before  passing  to  the  con- 
sideration of  these  deposits,  to  give  brief  descriptions  of  the  perid- 
otites  and  related  rocks,  in  order  that  the  descriptions  of  mines 
that  follow  may  be  more  fully  understood. 

The  rocks  to  be  considered  may  be  classed  in  three  groups, 
namely  :  peridotites,  pyroxenites,  amphibolites .  Of  these,  the  first 
group  largely  predominates,  and  the  others  are  regarded  as  only 
variant  or  accompanying  forms  of  the  same  geologic  unit.  They 
sometimes,  however,  attain  considerable  importance  as  independ- 
ent rock  masses. 

(1.)    THE    PERIDOTITES. 

The  peridotites  appear  in  numerous  small  oval  or  lenticular 
masses  of  dimensions  rarely  exceeding  a  few  hundred  feet.  Some- 
times these  lenses  merge  into  each  other  and  form  a  narrow  strip 
a  mile  or  two  in  length  with  constrictions  at  intervals,  thus  resem- 
bling, in  form,  a  string  of  sausages.  In  rare  cases,  the  outcrops  pre- 
sent an  irregular  boundary,  and  cover  areas  of  several  hundred 
acres.  The  Buck  creek  area  in  Clay  county,  and  that  at  Webster 
in  Jackson  county,  are  the  largest  masses  of  the  belt,  and  their 
form  and  extent  are  shown  approximately  on  the  small  scale 
map,  plate  I.     (See  also  plates  III  and  V.) 

These  rocks  are  in  general  perfectly  massive  and  structureless, 
though  a  parallel  structure  is  often  developed  about  the  borders; 
and  at  Webster  the  whole  mass  is  so  perfectly  laminated  as  to  pre- 


16 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


sent  a  striking  resemblance  to  a  thin-bedded  sandstone.  As  stated, 
however,  this  structure  is  exceptional,  even  the  small  bodies  and 
narrow  strips  preserving  a  perfectly  massive  character. 

This  is  often  true,  even  where  there  has  been  considerable  move- 
ment along  the  contacts  between  the  gneiss  and  peridotites,  result- 
ing in  the  frequent  development  of  mica-schist  in  the  adjoining 
gneisses  and  the  universal  presence  of  schistose  talc  in  the  borders 
of  the  dunite.  The  boandaries  have  thus  become  veritable  slick- 
ensides,  and  hence  no  true  contacts  between  the  peridotites  and 
gneisses  have  been  observed,  and  original  contact  metamorphism, 
if  such  ever  existed  here,  has  been  entirely  obliterated. 

The  peridotites  of  North  Carolina  represent  a  petrographic  unit; 
and  no  extensive  field  work  is  necessary  to  convince  one  that  any 
attempt  to  subdivide  them  must  proceed  on  comparatively  slight 
mineralogical  differences,  and  the  classes  established  regarded  as 
mere  varieties.  Thin  sections  cut  from  different  portions  of  the 
same  outcrop  might  be  made  the  basis  for  the  establishment  of 
three  or  four  petrographic  divisions;  but,  in  the  field,  the  lines  of 
separation  cannot  be  sharply  drawn.  The  classes  made  in  the 
laboratory  are  found  to  merge  into  each  other,  forming  parts  of 
the  same  rock  mass. 

However,  with  a  clear  understanding  of  this  unity,  the  estab- 
lished classification  of  the  peridotites  may  be  useful  for  purely 
petrographic  purposes;  and,  in  deference  to  usage,  the  more  prom" 
inent  types  observed  in  the  State  are  here  considered  separately 
These  are  dunite,  the  pure  olivine  rock;  harzburgite  (saxonite), 
that  composed  of  olivine  and  orthorhombic  pyroxene;  amphihole. 
picrite,  consisting  essentially  of  olivine  and  hornblende  ;  forell- 
enstein  (troctolite),the  olivine-feldspar  rock,  which  is  not  a  peridotite 
according  to  the  definition  of  that  class;  namely,  that  it  consists  o* 
olivine  rocks  without  essential  feldspar.  Forellenstein  is  usually 
regarded  as  a  phase  of  olivine-gabbro  produced  by  the  suppression 
of  the  pyroxene — indeed,  it  may  be  questioned  whether  most  perid- 
otites should  not  also  be  so  considered — but  on  the  ground  of  geo- 
logic unity,  it  is  here  classed  with  the  peridotites. 


THE    PERIDOTITES    AND    ASSOCIATED    MASSIVE    ROCKS.  17 


a.   DUNITK. 

The  type  of  this  rock  was  discovered  in  Dun  mountain,  New 
Zealand,  about  thirty  years  ago,  and  described  by  von  Hochstetter  as 
a  light  yellowish-green  to  grayish-green,  crystalline  granular  rock, 
with  an  oily  to  a  glassy  lustre,  and  an  uneven  angular  fracture. 
The  dull,  rust-brown  color  of  the  barren,  weathered  surface  gave 
the  mountain  its  name  and,  indirectly,  the  rock  itself.  It  was 
found  to  consist  almost  exclusively  of  granular  olivine,  with  chrom- 
ite  or  picotite,  in  octahedral  crystals  the  size  of  a  pin-head,  scat- 
tered through  the  mass. 

The  North  Carolina  dunite  is  very  close  to  this  type.  It  is 
usually  composed  of  quite  small  grains  of  olivine,  about  the  size 
of  granulated  sugar,  though  sometimes  much  coarser  rock  is  found 
in  small  quantities,  and  large  grains  are  often  scattered  through 
the  fine-grained  masses. 

Small  octahedrons  or  rounded  grains  of  chromite  or  picotite  are 
sparsely  scattered  through  nearly  all  the  olivine  rocks.  Sometimes 
these  become  very  plentiful,  and  are  then  frequently  segregated 
into  vein-like  streaks  or  pockets,  and  attain  importance  as  a  chrom- 
ium ore.  Long,  glistening  needles  of  tremolite  are  often  observed, 
and  sometimes  flakes  of  talc  and  chlorite. 

The  colors  include  nearly  all  shades  from  light  brownish  yellow 
to  a  dark  green,  though  the  freshest  specimens  seem  to  be  those  of 
light  oil-green  or  yellowish  green  color.  Brown  and  yellow  tints 
are  generally  more  superficial  and  seem  to  be  the  results  of  oxida- 
tion of  the  iron  constituent  in  the  incipient  stages  of  decomposi- 
tion ;  and  a  dark  green  color  may  sometimes  be  seen,  by  the  aid  of 
a  lens,  to  be  the  result  of  a  partial  alteration  to  serpentine.  The 
dark  green,  fine  grained  varieties  are  usually  tough,  and  the  coarser 
grained,  yellowish  ones  are  very  friable,  being  often  easily  crumbled 
with  the  fingers,  even  when  apparently  quite  fresh.  The  more 
thinly  laminated  varieties  about  Webster  and  elsewhere  are  usually 
partly  altered  and  quite  friable  also. 

The  characteristic  dull  brown  color  of  the  weathered  surface  is 
the  same  here  as  described  for  the  New  Zealand  rock.  By  decom- 
position,  an   ochreous  soil   is  produced   which,   on   account   of  its 


18  CORUNDUM    AND    BASIC    MAGXESIAX    KOCKS. 

infertility  and  the  cod  sequent  absence  of  vegetation,  is  easily 
removed  by  rains ;  and  hence  the  outcrops  are  nearly  always  made 
conspicuous  by  barren  areas  of  brown,  angular  rocks  in  a  region 
otherwise  well  wooded. 

Under  the  microscope,  in  ordinary  light,  dunite  is  seen  to  consist 
of  irregular,  angular  grains  of  translucent,  colorless  olivine.  In  the 
fresh  specimens,  the  angles  of  these  grains  fit  accurately  into  each 
other  with  no  interstitial  matter  whatever  (Plate  VI,  figure  1); 
though  in  the  great  majority  of  cases  there  has  been  a  slight  alter- 
ation along  the  cracks  into  serpentine,  and  this  secondary  material 
surrounds  every  grain  completely  like  mortar  in  a  rubble  wall. 
(Plate  VI,  figure  2.) 

The  microscope  also  reveals  the  fact  that  many  of  these  rocks 
now  of  fine  texture  have  resulted  from  cracking  up  the  grains  of  a 
much  coarser  rock.  In  this  process  the  remnants  of  these  origin- 
ally large  grains  have  suffered  very  little  or  no  displacement,  for 
in  polarized  light  they  still  extinguish  together  over  considerable 
areas.  (Plate  VI,  figure  3.)  In  some  cases,  however,  these  frac- 
tured grains  have  also  been  slightly  sheared,  and,  hence,  of  course, 
the  small  fragments  have  rolled  somewhat  on  each  other  and  the 
evidence  of  its  having  once  been  a  coarse  grained  rock  is  more  or 
less  completely  obliterated.  Sometimes,  too,  these  grains  show  the 
development  of  a  distinct  cleavage  parallel  to  the  brachypinacoidal 
plane  of  the  crystal ;  and  more  rarely,  a  basal  cleavage  is  devel- 
oped at  right  angles  to  this. 

Besides  olivine,  either  chromite  or  picotite,  while  neither  is  an 
essential  constituent  of  dunite,  is  always  present  in  rounded  grains, 
occasionally  in  crystals,  scattered  through  the  rock  ;  and  hence 
they  must  be  regarded  as  characteristic  accessories.  The  distinc- 
tion between  these  two  minerals  under  the  microscope,  if  indeed  a 
sharp  line  may  be  drawn  between  them  at  all,  is  often  quite  diffi- 
cult to  make.  No  chemical  or  other  special  investigations  have 
yet  been  made  in  connection  with  this  work,  and  the  two  names 
are  used  rather  loosely  in  the  descriptions  of  microscopic 
characters  of  the  rock.  A  review  of  a  considerable  amount  of 
literature  on  similar  studies  shows  quite  a  prevalent  indefinite- 
ness  in  referring  to  these  minerals,  and  emphasizes  the  need  of  more 


THE    PERIDOTITES    AND    ASSOCIATED    MASSIVE    ROCKS.  19 

thorough  chemical  and  microscopic  investigation  for  the  purpose 
of  establishing  definitely  the  relations  between  them. 

In  the  study  of  these  North  Carolina  rocks,  I  have  called  the 
opaque  mineral  that  shows  a  dull  grayish  color  by  reflected  light 
chromite  /  and  for  all  those  varieties  that  are  translucent  and  of  a 
yellowish  or  reddish  brown  color  I  have  used  the  name  picotite. 
The  thoroughly  unsatisfactory  nature  of  this  classification  is  more 
readily  understood  when  it  is  found  that  every  possible  gradation 
between  the  bright  yellowish  brown,  translucent  mineral  and  the 
dull,  opaque  one  are  found  in  the  same  rock,  and,  indeed,  may 
often  be  seen  in  the  same  thin  section.  The  most  natural  explanation 
of  these  facts  seems  to  lie  in  the  hypothesis  that  we  have  here  a 
complete  chemical  series,  as  pointed  out  by  Wadsworth* ;  and 
further  wTork  on  the  chemical  relations  of  these  minerals,  to  be  of 
the  greatest  value,  should  also  take  into  account  their  microscopic 
characters. 

In  some  of  the  oli vine-feldspar  rocks  described  below,  the  rela- 
tions are  even  more  striking  than  this ;  for  quite  frequently  the 
clear,  translucent  picotite  is  surrounded  by  a  border  of  opaque  min- 
eral with  a  sharp  line  between  them,  and  the  width  of  this  border 
varies  from  a  thin  peripheral  line  to  a  band  so  broad  that  there 
appears  only  a  minute  grain  of  translucent  mineral  in  the  middle. 

The  size  of  the  grains  of  chromite,  or  picotite,  as  the  case  may 
be,  usually  does  not  vary  very  widely  from  that  of  the  olivine 
grains,  though  sometimes  they  are  conspicuously  larger.  This  is 
usually  true  where  the  quantity  present  is  largely  in  excess  of  the 
normal,  so  that  prominent  segregations  of  it  appear,  sometimes 
attaining  the  importance  of  an  ore,  as  mentioned  above.  Masses 
of  such  ore  have  been  found  in  the  vicinity  of  Webster,  in  Jack- 
son county ;  near  Burnsville,  in  Yancey  'county ;  northwest  of 
Boone,  in  Watauga  county,  etc. 

Other  accessory  constituents  of  dunite  which  are  seen  under  the 
microscope,  and  which  sometimes  become  prominent  macroscopi- 
cally,  may  be  briefly  mentioned.  Enstatite  in  irregular  grains  is 
quite  often  seen,  and  is  sometimes  pleochroic.  Less  often,  diallage 
is  found.    A  light  green  hornblende,  in  elongated  prisms,  and  giving 

*Lithological  Studies,  Cambridge,  1884,  pp.  176-186. 


20  CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 

under  the  microscope  properties  of  aetinolite,  is  often  found  in  the 
rock  at  Buck  creek,  Clay  county,  and  sometimes  on  Shooting  creek. 

The  minerals  described  above  are  the  only  ones  that  have  been 
at  all  commonly  observed  in  the  perfectly  fresh  dunite.  As  soon 
as  alteration  begins,  there  appear  a  considerable  number  of  new 
minerals  among  the  secondary  products;  and,  as  has  been  already 
mentioned,  at  least  some  alteration  may  be  seen  in  most  of  the 
sections  when  examined  microscopically. 

By  far  the  most  prevalent  product  of  alteration,  and  one  that 
is  to  a  certain  extent  well-nigh  universal,  is  serpentine.  The  first 
stage  in  serpentinization  of  the  olivine  is  seen  in  the  narrow  line 
of  yellowish  or  greenish,  low-refracting  substance  that  appears 
along  the  borders  of  the  grains,  forming  a  fine  network,  which 
completely  envelops  the  olivine.  Later,  it  forms  along  the  irreg- 
ular fissures  and  cleavage  cracks  through  the  individual  grains 
themselves  ;  and  gradually,  as  these  are  altered  more  and  more 
along  their  borders,  the  serpentine  replaces  the  olivine  till  no 
trace  of  the  original  mineral  is  left. 

In  the  earlier  stages,  this  alteration  is  very  common,  almost 
universal,  in  the  dunite;  but,  in  North  Carolina,  complete  altera- 
tion, save  in  a  few  small  areas,  is  exceptional.  The  process  is  sel- 
dom carried  so  far  as  to  destroy  the  granular,  sandy  nature  of  the 
rock  over  any  considerable  area.  Plate  YI  (figures  1,  2,  4,  and 
5,)  shows  successive  stages  in  this  process,  together  with  some  of 
the  characteristic  phenomena  that  attend  it.  A  deposition  of  mag- 
netite in  fine  grains  in  the  beginning  of  the  alteration  is  very  com- 
mon, and  a  net-work  of  black  lines  is  thus  formed  that  often  out- 
lines the  original  olivine  grains  after  the  whole  has  passed  into 
massive  serpentine.  Sometimes  the  rejected  ferruginous  materials 
take  the  form  of  a  lower  oxid  and  stain  the  serpentine  and  also 
the  olivine  remnants  a  deep  yellowish  brown.  Where  cleavages 
are  developed  in  the  olivine,  the  alteration  to  serpentine  usually 
takes  place  more  readily  along  that  parallel  to  the  basal  plane, 
though  the  brachypinacoidal  cleavage  is  always  more  highly 
developed. 

The  same  difference  in  resistance  to  chemical  action  along  these 
two  planes  is  observed  in  the  development  of  chlorite  in  the  olivine. 


*J1  OTVJX  Q 


StaU  faibrary, 


THE    RERIDOTITES    AND    ASSOCIATED    MASSIVE    ROCKS.  21 

Chlorite  is  often  present  in  the  partially  serpentinized  specimens 
and  also  in  many  cases  where  there  is  no  serpentine.  The  horn- 
blende-bearing variety  (amphibole-picrite)  generally  shows  more 
or  less  alteration  of  the  hornblende  to  chlorite,  and  sometimes  only 
scattered  remnants  of  it  are  left  entirely  surrounded  by  the  sec- 
ondary product. 

But  chlorite  is  often  distinctly  the  result  of  alteration  of  the 
olivine  also,  as  seen  in  its  frequent  development  along  cracks  and 
cleavage  planes ;  and  still  more  conclusively  in  those  cases  where 
the  chlorite  penetrates  the  solid  olivine  grains  and  gradually 
replaces  them,  much  in  the  same  manner  as  serpentine.  In  such  alter- 
ation there  is,  of  course,  an  accession  of  alumina  from  some  source 
outside  of  the  olivine  itself,  this  mineral  being  simply  a  combina- 
tion of  the  silicates  of  iron  and  magnesium  in  varying  proportions 
and  entirely  free  from  alumina.  The  same  is  true  of  the  produc- 
tion of  talc,  which  is  much  less  frequent  in  these  rocks.  With  the 
formation  of  chlorite  there  also  occurs  a  segregation  of  the  fine 
grains  of  magnetite  into  irregular  patches  or  large  grains,  and 
these  are  frequently  given  a  skeleton  appearance  by  the  laths  01 
chlorite  that  penetrate  them.  Such  masses  of  magnetite  are  almost 
universally  surrounded  by  a  zone  of  chlorite  or  a  mixture  of  chlo- 
rite and  talc,  in  radiating  fibres  approximately  at  right  angles  to 
their  boundaries. 

Tremolite,  in  long  slender  needles,  is  often  present  with  serpen- 
tine and  chlorite,  and  is  sometimes  largely  developed  where  very 
little  of  the  other  two  has  be  enformed.  Its  secondary  nature  is 
unmistakable,  in  most  cases,  from  the  manner  in  which  it  pene- 
trates the  olivine  grains  in  every  direction,  often  passing  through 
several  in  succession  without  reference  to  the  orientation  of  cleav- 
ages or  crystallographic  axes.  The  tremolite,  in  turn,  is  frequently 
more  or  less  altered  to  talc  and  chlorite  ;  and  most  of  the  speci- 
mens showing  talc  also  bear  some  tremolite,  so  that  such  alteration 
may  often,  though  not  always,  account  for  the  presence  of  talc  in 
dunite.  In  some  cases  it  is  evidently  the  result  of  alteration  of 
enstatite,  as  shown  by  remnants  of  the  original  mineral  and  by  the 
form  which  the  talc  still  retains. 

Enstatite,  in  some  cases  at  least,  is  a  secondary  product,  as  often 


22 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


seen  in  the  radial  casing  which  it  forms  along  the  joint-planes 
of  the  dunite.  This  is  especially  prominent  at  the  north  end  of 
Corundum  Hill,  and  is  more  or  less  developed  in  a  great  many  of 
the  outcrops  throughout  the  State. 

The  casing  varies  from  an  inch  or  less  in  thickness  to  12  or  14 
inches,  and  generally  contains  more  or  less  chlorite  in  scattering 
scales  through  it.  It  is  always  fibrous  in  structure,  with  the  fibres 
arranged  approximately  normal  to  the  surface  of  the  enclosed 
dunite  ;  and  may  sometimes  be  separated  into  two  or  more  con- 
secutive layers,  practically  identical  in  structure  and  composition. 
The  outer  portions  of  these  casings  are  often  altered  to  talc,  and 
sometimes  this  has  been  rendered  schistose  by  subsequent  shearing 
so  as  to  wrap  these  portions  round  the  boulders  in  thin  laminae. 
Such  layers  are  seen  to  be  continuous  with  the  unaltered  portions 
of  the  casing  which  still  stand  perpendicular  to  the  surface  of  the 
enclosed  block  of  dunite. 

Casings  of  this  nature  are  often  broken  through  in  mining  for 
corundum,  and  the  enclosed  block  found  to  be  completely  altered 
to  a  yellow  ochreous  earth  that  easily  crumbles  on  exposure.  The 
connection  of  this  enstatite  with  the  corundum  veins  will  be  dis- 
cussed later   in   describing  the  modes  of  occurrence  of  corundum. 

Carbonates  in  small  quantities,  sometimes  forming  little  veins 
through  the  rock,  are  found  in  the  specimens  that  have  suffered 
considerable  alteration.  They  are  readily  recognized  under  the 
microscope  by  their  high  double  refraction  and  well-developed 
rhombohedral  cleavage.  ~No  tests  were  made  of  their  chemical 
nature,  but  they  are  doubtless  ordinary  magnesium  carbonate,  or 
magnesite. 

In  the  final  weathering  and  disintegration  of  dunite,  silica,  in 
the  form  of  chalcedony,  is  deposited  in  irregular  masses  in  he 
joints  and  cracks;  and  garnierite,  genthite,  and  other  nickel  bear- 
ing silicates  are  formed  in  cases  where  the  olivine  carries  small 
quantities  of  nickel.  These  minerals,  however,  never  form  impor- 
tant rock  masses,  though  the  nickel  minerals  have  been  found  in 
sufficient  quantity  in  some  localities  to  attract  attention  from  a 
commercial  standpoint. 

The  original  minerals  and  alteration  products  described  above 


THE    PERIDOTITES    AND    ASSOCIATED    MASSIVE    ROCKS.  23 

are  found  in  practically  all  the  dnnite  localities  of  the  State ;  in 
fact,  there  is  remarkably  little  variation  in  the  characters  of  the 
rock  throughout  the  region,  much  less  than  in  the  corundum  and 
its  associated  minerals.  Such  variations  as  do  exist  are  chiefly  in 
the  relative  proportions  of  the  various  minerals  resulting  from 
alternation  rather  than  in  the  original  constitution  of  the  rock, 
and  important  characters  of  this  nature  will  be  pointed  out  below 
in  enumerating  the  peridotite  localities. 

b.  harzburgite  (Saxonite). 

This  is  essentially  an  olivine-enstatite  rock  and  is  found  in  this 
region  chiefly  as  a  transition  between  the  dunite  and  the  enstatite 
rock  described  below,  though  there  are  a  few  exceptions  and  these 
are  of  sufficient  extent  and  importance  to  warrant  a  separate  con- 
sideration. The  two  principal  constituents  occur  in  very  variable 
proportions,  and,  besides  these,  all  the  accessory  minerals  of  dunite 
are  also  present.  The  olivine,  chromite,  etc.,  are  identical  with 
the  same  minerals  as  found  in  dunite,  and  the  enstatite  has  the 
same  essential  characteristics.  But  here  it  is  much  more  highly 
developed  and  becomes  an  essential  constituent,  being  always  pres- 
ent in  macroscopic  dimensions,  and  prominent  for  its  glistening 
cleavage  faces. 

The  alteration  processes  are  the  same  as  for  dunite.  The  ensta- 
tite alters  in  some  cat-es  to  serpentine,  just  as  described  for  olivine, 
but  oftener  it  changes  to  talc.  This  is  especially  true  of  the  ensta- 
tite in  the  pyroxenites  described  below.  Harzburgite  is  found 
principally  in  large  outcrops  near  Bakersville,  Mitchell  county,  and 
near  Elk  Cross  Roads,  Ashe  county;  Balsam  Gap,  Jackson  county; 
and  Mine  creek,  Yancey  county. 

C.    AMPHIBOI,E-PICRITE. 

This  rock  is  very  similar  in  structure  to  the  harzburgite  described 
above,  an  amphibole  (hornblende)  mineral,  resembling  actinolite, 
replacing  the  enstatite  as  an  essential  constituent.  Enstatite  is 
frequently  present,  however,  and  the  grains  and  crystals  of  chromite 
or  picotite  constitute  characteristic  accessories,  as  in  dunite.      The 


24 


CORUNDUM    AXD    BASIC    MAGXESIAX    ROCKS. 


hornblende  is  often  partially  or  wholly  altered  to  chlorite,  and  it 
is  very  probable  that  the  chlorite  of  the  olivine  rocks  of  this  region 
may  have  originated  often  in  this  manner.  A  considerable  por- 
tion of  the  Buck  creek  peridotite  mass,  especially  towards  the 
north  end  of  the  mountain,  is  composed  of  rock  which  conforms 
closely  to  this  type. 

d.  forKIvLExsteix  (Troctolite). 

This  rock  type,  composed  essentially  of  olivine  and  feldspar,  has 
been  found  in  important  development  at  only  one  locality ; 
namely,  on  the  eastern  border  of  the  dunite  area  at  Buck  creek, 
in  Clay  county.  It  is  also  found  in  small  amounts  on  Shooting 
creek,  where  the  rock  associations  are  similiar  in  many  ways  to 
those  of  Buck  creek.  The  whole  outcrop  at  the  former  place  covers 
an  area  of  only  about  two  acres,  but  it  is  interesting  on  account 
of  its  connection  with  the  dunite,  instead  of  with  gabbro,  as  usually 
found,  and  also  on  account  of  the  rarity  of  this  type  of  rock. 
So  for  as  I  am  aware,  this  is  the  first  recorded  instance  of  forellen- 
stein  as  a  phase  of  peridotite. 

The  rock  is  composed  almost  entirely  of  olivine  and  a  basic 
feldspar  (anorthite),  and  the  zones  of  intermediate  silicates  devel- 
oped along  the  borders  between  these  minerals. 

A  small  amount  of  feldspar  that  was  separated  by  heavy  solution 
for  analysis  showed  some  kaolinization  when  examined  with  the 
microscope,  but  the  following  partial  analysis  places  it  unmistak- 
ably with  anorthite. 

Partial  Analysis  of  Feldspar  (Anorthite)  from  Forellenstein  of  Buck 
Creek,  Clay  County,  N.  C. 


Percentage      On  basis  of  100 
Determined.  per  cent. 


Silica 

40.40 
18.72 
36.40 

42.29 

Alumina  

Lime 

19.60 
38.11 

95.52 

100.00 

PYROXENITES ENSTATITE    KOCK.  25 

The  percentages,  calculated  on  a  basis  of  100,  are  only  approxi- 
mately correct  for  the  pure  mineral,  as  magnesia  probably  exists 
in  combination  with  part  of  the  silica.  The  quantity  available 
was  too  small  to  give  more  than  approximate  results. 

In  this  rock,  the  olivine  nowhere  borders  directly  on  the  feld- 
spar, but  it  is  separated  from  it  by  a  double  zone  of  fibrous  miner- 
als, arranged  at  right  angles  to  the  boundaries.  Rarely,  one 
portion  is  absent  and  the  minerals  are  separated  only  by  a  single 
zone.  Such  reaction  rims  have  been  described  often  from  olivine 
gabbros,  and  their  optical  properties  were  carefully  studied  by  Dr. 
F.  D.  Adams,  in  an  occurrence  in  the  anorthosites  of  Canada, 
which  is  exactly  similar  to  this  North  Carolina  rock,  except  that 
the  reaction  rims  of  the  latter  are  somewhat  more  highly  developed 
than  in  any  occurrence  heretofore  described. 

Dr.  Adams  found  that  the  portion  of  this  zone  adjacent  to  the 
olivine  corresponded  in  optical  properties  with  enstatite,  and  that 
the  other  part  is  made  up  of  a  fibrous  green  hornblende.  In  the 
North  Carolina  rock,  this  latter  is  sometimes  perfectly  continuous 
with  large  cleavable  masses  of  hornblende,  and  its  identity  is  thus 
easily  recognized  microscopically.  But  the  other  portion  cannot 
be  satisfactorily  determined  without  separation  of  the  minerals 
from  the  powdered  rock,  and  this  I  hope  to  do  before  the  publica- 
tion of  the  final  report  on  these  rocks. 

(2.)  PYROXENITES. 

Two  types  of  this  family  are  found  in  closest  connection'  with 
the  peridotites,  and  sometimes  passing  gradually  into  them,  though 
usually  much  more  sharply  differentiated  than  the  different  varie- 
ties of  the  peridotite  from  each  other.  Two  very  distinct  types  of 
pyroxenite  have  been  observed,  namely,  that  composed  of  ortho- 
rhombic  pyroxene,  enstatite  rock ;  and,  one  consisting  of  both 
monoclinic  and  orthorhombic  pyroxenes,  websterite. 

a.    ENSTATITE)   ROCK. 

This  rock,  as  its  name  indicates,  is  composed  chiefly  of  the  ortho- 
rhombic  pyroxene,  which  is  usually  in  large  bladed,  interlocking 

2 


26  CORUNDUM    AND    BASIC    MAGNE8IAN    ROCKS. 

crystals  of  a  grayish  or  yellowish  color.  In  some  places  where  it  is 
considerably  developed  it  forms  a  mass  perfectly  continuous  with  the 
dunite,  as  at  Corundum  Hill,  Macon  county,  and  in  some  of  the 
outcrops  of  the  Sapphire  mine  in  Jackson  county.  At  other 
Sapphire  localities,  and  especially  in  Transylvania  and  Watauga 
counties,  it  forms  separate  rock  masses  of  considerable  extent. 
Besides  occasional  grains  of  olivine  and  chromite,  this  rock  scarcely 
contains  anything  else  than  enstatite  and  its  alteration  products. 

The  alteration  consists  entirely,  so  far  as  observed  in  this  region, 
of  a  change  into  talc.  Even  the  freshest  looking  specimens  often 
have  greenish,  transparent  talc  developed  in  them,  and  frequently 
large  masses  that  have  undergone  this  alteration  still  retain 
perfectly  the  form  and  appearance  of  the  original  mineral.  This 
is  often  true  also  of  talc  in  enstatite-bearing  peridotite  (harzburg- 
ite),  as  may  be  seen  in  that  near  Balsam  gap,  in  Jackson   county. 

Dr.  C.  D.  Smith  considered  the  chief  constituent  of  this  rock  to 
be  anthophyllite,*  and  the  same  term  has  been  employed  by  some 
later  writers.  Rocks  of  a  similar  character  at  the  Pine  Mountain 
mine,  Rabun  county,  Georgia,  are  also  called  anthophyllite  by  Mr. 
Francis  P.  King.* 

In  view  of  this  usage  and  the  extreme  scarcity  of  well  deter- 
mined localities  for  true  orthorhombic  amphibole,  I  had  a  specimen 
of  the  mineral  from  Corundum  Hill  analyzed  in  the  laboratory  of 
the  Survey  by  Dr.  Charles  Baskerville,  with  the  result  given  below 
in  column  I.  Talc  could  be  seen  in  small  amounts  in  the  specimen 
from  which  the  sample  was  taken.  This  was  carefully  excluded 
from  the  material  analyzed,  but  the  high  percentage  of  water  shows 
that  considerable  alteration  had  taken  place.  There  can  be  no 
doubt,  however,  of  the  true  character  of  the  mineral.  Deducting 
the  water  and  calculating  the  percentage  on  the  basis  of  100,  we 
obtain  the  results  given  in  column  II.,  and  these  figures  represent 
a  normal  enstatite  with  a  high  iron  constituent,  and  near  the 
bronzite  variety. 

*Report  Geol.  Sur.  N.  C  L,  1875,  appendix,  page  93. 
♦Bulletin  2,  Geol.  Sur.  of  Georgia,  1894.  pages  79,  82,  etc. 


PYKOXENITES WEBSTERITE. 


27 


An  analysis  of  another  specimen  from  the  same  locality   by  Mr. 
Frank  Julian*  is  given  in  column  III,  for  comparison. 


Analyses  of  enstatite  from  Corundum  Hill,  Macon  county  : 


I. 

II. 

III. 

Silica  

51.64 
0.12 
9.28 
0.45 

31.93 
0.56 
5.45 

54.95 

57.30 

Alumina 

trace 

Ferrous  oxid 

9.87 

7.45 

Lime 

Magnesia 

33.97 

34.64 

Manganese  oxid 

Water 

1.21 

99.43 

100.60 

No  other  specimens  have  been  determined,  and  the  name  is 
applied  to  rocks  of  other  localities  on  general  resemblance.  It 
is  possible  that  some  of  them  may  prove  to  be  of  a  different  nature. 

b.   WEBSTERITE. 

This  rock  was  first  described  and  named  by  the  late  Dr.  G.  H. 
Williams  from  specimens  collected  at  Webster,  Jackson  county.* 
Thus  far,  besides  the  type  locality  near  the  town  of  Webster,  it 
has  been  observed  only  in  the  continuation  of  the  same  outcrop  of 
dunite  on  Cnne  creek,  about  six  miles  further  east.  It  is  composed 
of  both  orthorhombic  and  monoclinic  pyroxenes  in  a  compact,  gran- 
ular mass,  closely  resembling  the  dunite  with  which  it  is  associated, 
and  forming  a  part  of  the  same  rock  mass.  So  far  as  observed, 
however,  there  is  no  gradual  transition  from  one  to  the  other,  the 
two  types  remaining  quite  distinct. 

The  Webster  dunite,  as  before  stated,  is  very  highly  laminated, 
and  in  the  midst  of  this  rock,  which  appears  on  a  hillside  facing 
the  Tuckaseegee  river  in  an  outcrop  over  1,500  feet  wide,  the  web- 
sterite  occupies  a  width  of  about  300  feet.  It  may  be  traced  for 
about  a  mile  in  length,  in  this  type  locality ;  then  it  thins  out  and 
does  not  appear  again,  except  in  the  Cane  creek  outcrop  mentioned 

♦Bulletin  74,  TJ.  S.  Geol.  Sur.,  Minerals  of  North  Carolina,  1891,  page  43. 
♦American  Geologist,  VI,  1890,  pages  41-44.    . 


28  CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 

above.  It  is  more  massive  in  character  than  the  dunite,  has  a  more 
brilliant  green  color,  and  is  less  altered  on  the  surface.  It  is  also 
quite  prominent  in  the  field,  owing  to  the  vigorous  vegetation 
which  it  supports,  in  contrast  with  the  barren  dunite. 

(3.)    AMPHIBOLITE. 

This  term  is  here  used  to  indicate  massive  rocks  composed 
wholly  or  chiefly  of  amphiboles.  The  most  important  to  be 
considered  here  is  the  beautiful  green,  feldspathic,  hornblende 
rock,  which  often  bears  pink  and  red  corundum  in  the  Shoot- 
ing creek  and  Buck  creek  localities  of  Clay  county.  It  is 
principally  composed  of  grass-green  hornblende  and  the  lime- 
feldspar,  anorthite,  in  greatly  varying  proportions  ;  and  its  struc- 
ture is  usually  laminated  and  gneissic,  though  massive  forms  are 
not  entirely  wanting.  The  corundum  which  it  bears  occurs  in 
masses  from  the  minutest  microscopic  grains  to  broad  cleavable 
plates  three  or  four  inches  in   diameter. 

The  rock  is  very  fine-grained  and  exceedingly  tough  ;  and,  hence, 
it  has  not  been  found  practicable  to  crush  it  for  the  separation  of 
the  corundum.  Transitions  from  this  type  to  the  dunite,  with 
which  it  occurs,  are  found  on  top  of  the  mountain  west  of  the  mine, 
at  Buck  creek.  The  intermediate  stages  have  about  the  same  com- 
position and  structure  as  the  forellenstein  described  above  ;  but 
they  never  assume  sufficient  importance  in  this  connection  to  be 
classed  as  a  separate  rock.  The  relations  of  this  rock  to  the  dunite 
(see  map,  plate  III)  is  strongly  suggestive  of  a  system  of  dikes 
cutting  the  latter.  On  Shooting  creek,  Clay  county,  it  usually 
occurs  in  narrow  strips  beside  the  dunite,  though  sometimes  in 
masses  of  equal  size. 

The  hornblende  of  this  rock  has  usually  been  referred  to  the 
species  smaragdite*  but  analyses  show  it  to  be  an  aluminous  horn- 
blende, and  the  late  Professor  Dana  classed  it  with  edenite.  The  bril- 
liant color  is  undoubtedly  due  to  the  chromium  present.  This  is  more 
plainly  seen  when  the  powder  of  the  rock  is  examined  under  the 

*F.  A.  Genth,  Bulletin  74,  U.  S.  Geological  Survey,  1891,  45.    F.  P.  King,  Bulletin  2,  GeoL 
Survey  of  Georgia,  1894, 44,  45. 


AMPHIBOLITES. 


29 


microscope.  When  the  mineral  is  separated  from  this  powder  with 
heavy  solutions,  the  heavier  fragments  are  all  seen  to  contain 
inclusions  of  picotite  in  minute  grains,  and  to  be  of  a  much 
brighter  green  immediately  around  these  inclusions.  This  will 
account  for  some  of  the  chromic  oxid  found  in  analyses.  The 
purer  mineral  thus  separated  was  analyzed  by  Dr.  Charles  Basker- 
ville,  with  the  results  given  in  column  I.  That  in  column  II  is  an 
analysis  of  the  same  mineral  (without  separating  the  grains  with 
picotite)  given  by  Dr.  Grenth  in  the  bulletin  referred  to  above. 

Analyses  of  Aluminous  hornblende  from  Buck  creek,  Clay  county : 


I. 

II. 

Silica  

44.38 

17.32 

0.38 

3.83 

45.14 

Alumina 

17.59 

Chromic  oxid  

0.79 

Ferrous  oxid 

3.45 

Nickelous  oxid 

0.21 

Magnesia  

15.48 
0.90 

11.51 
1.24 
0.38 
4.63 

16.69 

Manganese  oxid 

Lime 

12.51 

Soda 

2.25 

Potash 

0.36 

Water 

1.34 

Specific  gravity 

100.03 
3.075 

100.33 
3.120 

The  specific  gravity  given  by  Dr.  Genth  was  determined  on  the 
grass-green  variety,  and  it  is  natural  to  suppose  that  picotite  inclu- 
sions cause  the  greater  weight  as  well  as  the  higher  chrome  per- 
centage. Feldspar  was  separated  and  found  to  agree  both  in  spe- 
cific gravity  and  extinction  angles  with  typical  anorthite. 


30  CORUNDUM    AND    BASIC    MAGNESIAS'    ROCKS. 


4.     ASSOCIATED  SECONDARY  AND  SCHISTOSE  ROCKS. 

Besides  the  schistose  phases  of  the  massive  rocks  described 
above,  there  are  found  frequent  large  masses  of  talc-  and  chlorite- 
schists  in  connection  with  the  typical  dunite,  as  well  as  with  the 
other  associated  rocks.  Serpentine  is  extensively  developed  in  only 
one  portion  of  the  region,  and  is  evidently  an  altered  dunite. 

(1.)    MASSIVE  ROCKS. 
a.   SERPENTINE. 

Massive  serpentine  is  almost  the  universal  result  of  exposure  of 
olivine  rocks  to  hydration  process.  These  rocks  in  Xorth  Car- 
olina have  been  subjected  to  this  alteration  in  but  few  places. 
Throughout  the  greater  portion  of  the  belt,  the  outcrops  of  the 
peridotites  are  almost  perfectly  fresh  to  the  very  surface  of  the 
exposure ;  and  such  alteration  as  has  taken  place  is  usually  in  the 
nature  of  a  direct  decomposition  of  the  olivine,  forming  magne- 
sium carbonate,  which  is  mostly  carried  away  in  solution,  and  a 
residue  of.  limonite  and  silica,  the  latter  remaining  as  chalcedony. 
As  stated  in  the  description  of  dunite,  however,  most  of  the  sec- 
tions of  this  rock  show,  under  the  microscope,  some  slight  altera- 
tion to  serpentine  along  the  cracks;  and  it  seems  quite  probable 
that  this  is  the  first  stage  in  the  decomposition  and  disintegration 
of  the  rock  through  ordinary  weathering  processes. 

The  production  of  serpentine  scarcely  reaches  a  greater  develop- 
ment, in  the  majority  of  cases,  than  to  form  a  thin  net-work  along 
the  cracks  of  the  olivine  ;  and  this  is  seldom  perceptible  to  the 
naked  eye.  On  the  most  exposed  surfaces,  where  the  rock  is  super- 
ficially stained  by  the  iron  oxids  of  the  decomposing  olivine,  the 
typical  granular  structure  is  still  retained;  and,  with  the  excep- 
tion of  a  small  area  at  Buck  creek,  Clay  county,  there  is  no  devel- 
opment of  massive  serpentine  south  of  Waynesville. 

But  very  different  conditions  have  evidently  prevailed  somewhat 
further  north  ;  for  in  Buncombe,  Madison,  and  Yancey  counties 
we  find   these  granular  rocks  largely  altered  to   typical,  massive 


ASSOCIATED    SECONDARY    AND    SCHISTOSE    ROCKS.  61 

serpentine.  The  outcrops  appear  in  the  same  form  as  found  in  the 
olivine  rocks,  and  the  characteristic  chromite  grains  are  always 
present.  Under  the  microscope,  thin  sections  often  also  show  the 
original  granular  nature  of  the  rock  in  the  net-like  or  "mesh" 
structure  of  the  fibrous  serpentine  bands  that  were  first  formed 
around  the  olivine  grains.  This  structure  is  still  more  emphasized 
if,  as  is  often  the  case,  in  the  early  stages  of  serpen tinization,  there 
was  a  separation  of  magnetite  or  other  ferruginous  material  along 
these  bands. 

A  serpentine  retaining  quite  a  large  percentage  of  unaltered 
olivine  is  found  on  Ivy  river,  in  Madison  county.  Sections  of  this 
rock,  seen  under  the  microscope,  have  the  appearance  of  that 
shown  in  plate  YI,  figure  4 ;  and,  in  some  cases,  the  olivine 
grains  are  quite  distinctly  seen  with  the  unaided  eye. 

However,  most  of  the  serpentine  represented  on  the  map,  espe- 
cially that  in  the  vicinity  of  the  French  Broad  river  below  Ashe- 
ville,  is  massive  and  of  light  to  dark  green  color,  and  is  in  every 
way  similar  to  that  of  Maryland  and  Pennsylvania,  in  the  north- 
ward continuation  of  the  belt.  In  these  States,  it  is  quarried  for 
architectural  purposes,  and  may  be  seen  in  many  buildings  in  the 
cities  of  Washington,  Baltimore,  and  Philadelphia.  There  would 
seem  to  be  no  special  reason  why  the  serpentine  of  North  Carolina 
should  not  be  used  in  the  same  maimer,  especially  wThere  trans- 
portation facilities  are  good.  Stone  of  good  color  is  available  in 
many  of  the  localities  indicated  on  the  map  ;  but  thus  far,  no 
attempt  has  been  made  to  utilize  it.* 

Many  people  in  the  corundum  region  of  North  Carolina  use  the 
term  serpentine  indiscriminately,  and  in  most  cases  incorrectly,  for 
any  rock  of  the  peridotite  belt,  especially  when  associated  with 
corundum. 

*See  "Notes  on  Building  and  Ornamental  Stone,11  by  J.  V.  Lewis.  1st  Biennial  Report  of 
the  State  Geologist,  1893,  pages  101, 102. 


32 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


(2.)    SCHISTOSE    ROCKS. 


a.    TAI.C-SCHIST,    SOAPSTONE. 


As  already  mentioned  in  the  geologic  sketch  of  this  region, 
there  is  always  a  greater  or  less  development  of  talc  along  the 
boundaries  of  the  peridotites  and  pyroxenites,  separating  them  from 
the  gneisses  of  the  country.  But  there  are  considerable  masses  of 
enstatite  rock  sometimes  entirely  altered  to  talc.  Such  rocks  may, 
and  sometimes  do,  retain  the  form  and  appearance  of  the  original; 
but  generally  they  have  been  rendered  schistose  by  subsequent 
shearing. 

Besides  these  larger  masses,  narrow  strips  of  schistose  talc  are 
very  generally  developed  along  lamination  of  the  gneisses  as  a  con- 
tinuation of  the  outcrops  of  the  magnesian  rocks;  and  these  some- 
times connect  two  or  more  lenticular  masses  of  dunite  or  pyroxenite 
across  intervals  of  two  or  three  miles.  The  width  of  such  strips 
seldom  exceeds  ten  or  fifteen  feet,  and  is  very  frequently  less. 
They  are  composed  of  rather  pure,  white  and  grayish  talc,  and  are 
always  schistose.  Their  chief  importance,  of  course,  lies  in  their 
close  connection  with  the  massive  rocks.  All  the  talcose  rocks, 
frequently  the  chloritic  schists,  and  sometimes  even  the  peridotites 
are  locally  termed  "soapstone,"  or  "serpentine." 

In  many  portions  of  the  peridotite  belt,  especially  in  the  north- 
western counties  of  North  Carolina,  soapstone  of  the  firmer  and 
more  massive  varieties  assumes  considerable  importance  on  account 
of  its  extensive  local  use.  Its  great  resistance  to  heat  makes  it  a 
most  enduring  material  for  the  construction  of  fireplaces  ;  and  its 
use  for  this  purpose  is  almost  universal  in  regions  where  it  can 
be  readily  obtained.  It  is  easily  cut  into  desired  shapes  with 
ordinary  saws,  axes,  and  planes,  such  as  are  used  in  wood-work. 
While  the  copper  mine  was  operated  at  Ore  Knob,  Ashe  county, 
great  quantities  of  soapstone  were  used  for  furnace  linings,  all  of 
which  was  cut  from  the  neighboring  peridotite  belt  in  Ashe  and 
Alleghany  counties.  This  material  also  finds  an  extensive  local 
use  for  tombstones  on  account  of  the  ease  with  which  it  is  shaped 
and  lettered. 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  11,  PLATE  II. 


/ 


DISTRIBUTION    OF    PETtLDOTITES    AND    ASSOCIATED    EOCKS.  33 

b.    CHLORITE-SCHIST. 

Where  corundum  is  found  in  connection  with  dunite,  there  is 
always  more  or  less  chlorite  developed  about  the  borders  of  the 
rock  mass  and  through  the  larger  joints  ;  but  the  chlorite  itself,  in 
such  cases,  never  assumes  the  importance  of  a  rock.  In  certain 
localities,  however,  especially  on  the  waters  of  the  Tuckaseegee 
river  above  Webster,  there  are  narrow  strips  of  chlorite  rock,  com- 
parable in  many  ways  to  those  of  talc  described  above,  but  in  no 
way  connected  with  known  olivine  rocks.  They  are  apparently 
independent  masses,  usually  schistose  in  character,  and  sometimes 
bear  corundum.  In  these  cases  the  corundum  is  surrounded  by 
alteration  zones  of  muscovite,  but,  besides  the  chlorite,  the  rock 
has  no  other  prominent  constituent.  The  chlorite  rocks  are  often 
talcose,  and  sometimes  pass  over  into  the  type  described  above. 
Whether  talcose  or  not,  they  are  usually  known  to  the  people  as 
"blue  soapstone."  , 

5.    DISTRIBUTION    OF  PERIDOTITES  AND  ASSOCIATED   ROCKS. 

(1.)    IN    THE    APPALACHIAN  BELT. 

A  great  peridotite-serpentine  belt,  coextensive  in  length  with 
the  Appalachian  mountain  system  (see  map,  plate  II),  traverses  the 
crystalline  schists  and  gneisses  from  Tallapoosa  county  in  eastern 
central  Alabama,  where  these  rocks  emerge  from  beneath  the  later 
formations  to  the  southward,  to  Trenton,  New  Jersey,  where  they 
disappear  for  a  space  under  the  younger  sedimentary  rocks  to  the 
northward.  Throughout  this  distance  of  over  800  miles,  the  perid- 
otites  are  found  along  a  narrow  belt  of  disconnected  outcrops 
with  an  approximate  trend  of  north  45°  east. 

In  the  southern  half  of  this  belt,  dunite  is  the  prevailing  type  of 
rock,  but  in  Virginia,  Maryland,  and  Pennsylvania,  it  is  repre- 
sented only  by  the  secondary  forms — serpentine  and  talc  rocks. 
Chromite  is  almost  a  constant  accompaniment  throughout  the 
region,  and  in  Pennsylvania,  North  Carolina,  South  Carolina, 
Georgia,  and  Alabama,  corundum  is  also  found  in  the  same 
connection. 


M 


CORUNDUM    AND    BASIC    MAGNP]SIAN    HOCKS. 


With  the  reappearance  of  the  crystalline  belt,  we  find  serpentine 
again  at  Hoboken,  New  Jersey,  and  on  Staten  island.  Other 
occurrences  of  a  similar  nature  are  found  in  northern  New  York, 
Massachusetts,  Vermont,  northern  New  Hampshire,  and  at  Deer 
island  on  the  coast  of  Maine.  The  distribution  of  these  rocks  is 
indicated  on  the  accompanying  map,  plate  II.  The  occurrence  of 
corundum  in  these  regions  is  discussed  further  on,  but  it  may  be 
stated  here  that,  with  two  exceptions,  it  is  not  found  with 
olivine  rocks  north  of  Pennsylvania.  The  two  localities  excepted 
are  the  emery  deposits  of  Westchester  county,  New  York,  and  the 
corundum  found  at  Pelham,  Massachusetts. 

(2.)    IN    NORTH    CAROLINA. 


The  highest  development  of  these  magnesian  rocks  is  attained  in 
North  Carolina,  where,  in  the  southwestern  connties,  the  outcrops 
are  thickly  scattered  over  a  region  nearly  forty  miles  in  width.  In 
this  region  also — at  Buck  creek,  in  Clay  county,  and  at  Webster, 
in  Jackson  county  (see  plates  III  and  Y) — occur  the  two  largest 
dunite  outcrops  of  the  whole  belt,  covering  areas  of  approximately 
three-fourths  and  one-half  a  square  mile  respectively.  It  will  be 
seen,  however,  that  the  amount  of  corundum  bears  no  relation  to  that 
of  the  dunite  ;  for  very  little  corundum  has  been  found  at  Webster, 
while  the  mine  at  Corundum  Hill,  (see  plate  IY)  which  has  fur- 
nished a  steady  output  of  corundum  for  seventeen  years,  covers  an 
area  of  only  ten  acres. 

A  more  detailed  description  of  localities  is  desirable  in  order  to 
point  out  local  characteristics  and  variations  in  the  rocks  that 
could  not  be  represented  on  the  map. 

Along  the  southern  boundary  of  the  State,  tliese  rocks  group 
themselves  roughly  into  three  sub-belts,  located  approximately  in 
the  valleys  of  the  Chattooga,  the  Little  Tennessee,  and  the  Hi- 
wassee  rivers,  though  none  of  these  retains  its  individuality  for 
any  considerable  distance.  In  Union  county,  Georgia,  two  and 
a  half  miles  south  of  the  Towns  county  line,  is  the  Track  Rock 
corundum  mine.  The  magnesian  rocks  outcrop  here  chiefly  in  the 
form   of   talcose  chlorite   schist.     Little   typical   dunite  is   found, 


DISTRIBUTION    OF    PERIDOTITES    AND    ASSOCIATED    ROCKS.  35 

though  olivine  grains  are  sometimes  seen  in  the  chlorite  on  the 
fresh  fracture,  and  an  altered  dunite  was  found  here  bj  Mr.  Francis 
P.  King,  of  the  Geological  Survey  of  Georgia. *  This  outcrop 
is  continued  for  two  or  three  miles  both  north  and  south  of  the 
gap,  by  talcose  rocks;  and  northward  the  line  is  almost  continu- 
ous to  the  the  Hamilton  mine,  which  is  located  about  a  mile  and  a 
half  south  of  the  North  Carolina  line.  Near  the  road,  about  a 
mile  north  of  Young-Harris,  is  a  small  mass  of  forellenstein,  and, 
so  far  as  observed,  this  is  the  only  exception  to  the  prevalent  talc- 
chlorite  rocks  of  this  line. 

From  this  point,  the  line  of  outcrop  drops  back  five  miles  to 
the  east,  and  appears  again  in  normal  dunite  a  mile  and  a  half 
north  of  Hiawassee.  Here  a  long  strip  of  laminated  dunite  crosses 
the  road  and  may  be  followed  for  more  than  half  a  mile;  and,  a 
little  further  up  Bell  creek,  two  oval  masses  occur  very  near 
together,  with  dimensions  of  400  or  500  feet.  Near  this,  on  the 
north  slope  of  Bell  knob,  is  a  band  of  talc  rocks  interlaminated  with 
gneiss,  and  the  talc  is  found  in  almost  a  continuous  line  to  the 
waters  of  Shooting  creek  in  Clay  county,  North  Carolina. 

a.    CIvAY   COUNTY. 

Here  considerable  chlorite  is  found,  gradually  passing  into  less 
altered  dunite  near  Shooting  creek  postoffice.  After  an  interval 
of  two  miles,  this  line  is  again  found  at  the  foot  of  Chunky  Gal  moun- 
tain, composed  of  dunite  and  considerable  schistose  talc,  in  a  strip 
rarely  attaining  a  width  of  forty  feet,  but  continuous  for  three 
miles  across  the  mountain,  and  disappearing  within  a  mile  of  the 
great  Buck  creek   area. 

Three  miles  above  the  mouth  of  Shooting  creek,  in  the  vicinity 
of  Elf  postoffice,  are  two  other  narrow  strips  of  dunite  very  close 
together  and  lying  parallel  in  the  lamination  of  the  gneiss  for 
about  a  mile.  Occasionally  feldspathic  phases  are  developed  in 
these  rocks,  and  in  one  place  a  peculiar  lamination  is  found  where 
feldspar  and  enstatite  alternate  with  olivine  in  laminae  of  half  an 
inch  to  three  inches  in   thickness.      This  lamination   is   almost  at 

^'Bulletin  No.  2,  Geological  Survey  of  Georgia,  p.  93. 


36 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


right  angles  to  that  of  the  gneiss,  and  the  whole  is  enclosed  in 
massive  dunite.  Accompanying  the  western  strip  almost  its  entire 
length,  is  amphibolite,  varying  all  the  way  from  almost  pure  feld- 
spar to  pure  hornblende  rock.  The  latter  is  of  a  brilliant  grass- 
green,  and  sometimes  bears  beautiful  red  corundum.  This  strip 
differs  also  from  the  other  in  being  continued  northeastward  for 
nearly  three  miles,  by  a  narrow  line  of  talc  outcrops. 

We  now  come  to  the  Buck  creek  area,  which  is  the  largest 
compact  mass  of  peridotite  in  the  State,  and  in  fact,  the  largest 
yet  observed  in  the  Appalachian  belt.  There  is  a  greater  surface 
exposure  in  the  vicinity  of  Webster,  but  it  is  drawn  out  into  con- 
siderable length,  and  in  that  respect  differs  markedly  from  that  at 
Buck  creek. 

The  form  and  extent  of  this  outcrop  are  shown  in  plate  III, 
which  is  reduced  from  a  large-scale  map  made  during  the  summer 
of  1894.  Points  of  especial  interest,  which  will  be  dwelt  on  more 
fully  in  a  later  report,  are  the  amphibolite  and  forellenstein  and 
their  relations  to  the  dunite,  the  arms  (apophyses)  passing  into  the 
surrounding  gneiss,  and  the  structure  of  the  gneiss  itself.  In  a 
general  way  these  points  are  shown  in  the  accompanying  map 
(plate  III)  sufficiently  well  not  to  require  further  description  here. 
The  area  of  this  outcrop  is  approximately  half  a  square  mile. 

b.    MACON    COUNTY. 

The  broad  region  over  which  the  peridotites  occur  in  this  county, 
as  contrasted  with  the  width  elsewhere,  especially  northward, 
would  seem  to  indicate  that  considerable  disturbance  has  taken 
place  here.  Whatever  theory  may  be  adopted  to  account  for  the 
origin  of  the  peridotites,  the  conclusion  that  a  number  of  parallel 
breaks  (fault-planes,  or  fissures)  have  been  formed  in  this  region  is 
one  that  is  readily  suggested  by  a  study  of  the  map  (plate  I).  A 
mile  or  two  south  of  the  State  line,  in  Rabun  county,  Georgia, 
small  lenticular  masses  of  dunite  and  enstatite  rock  are  devel- 
oped on  Bettys  creek.  Much  of  this  enstatite  is  quite  fibrous  and 
abestiform. 

On  the  road  from  Franklin,  North  Carolina,  to  Clayton,  Georgia, 
and  almost  on  the  State  line,  is  an  outcrop  of  dunite  with  consid- 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  11,  PLATE  IV. 


LEGEND: 


Dunite 

',', 

Gneiss 

(Showing  directions  of  strike  and  dip.) 

%M. 

Mica-Schist 

Corundum  Workings 

MAP  OF 

CORUNDUM    HILL 

Macon   County,  N.C. 

r>u  J.  Volncij  Lewis,  1B95. 

Topography  by  Chas.  E  Cooke. 

Contour  Interval  10  feet. 

SCALE  OF  FEET: 
100  000  300 


ESG'D  PY  AMERICAN  cask  NOTE  CO. 


FIGURES    ON    CONTOUR    LINES    GIVE    ELEVATIONS    ABOVE    AN    ARBITRARY    BASE  — THE    FLAT    ROCK    BED    OF    THE    BRANCH 
NEAR    THE   SOUTHWESTERN    CORNER    OF   THE    MAP. 


DISTRIBUTION    OF    PERIDOTITES    AND    ASSOCIATED    ROCKS.  37 

erable  schistose  talc ;  and  for  fifteen  miles  down  the  Little  Tennes- 
see river,  numerous  small,  often  entirely  isolated,  outcrops  are 
scattered  over  the  country.  These  arrange  themselves  approxi- 
mately in  lines  and  are  represented  on  the  map  as  continuous 
masses,  where,  strictly,  there  should  be  a  number  of  small  dots. 
Some  of  these  are  enstatite,  and  they  are  often  represented  on  the 
surface  only  by  the  talc  that  has  resulted  from  their  alteration. 

Between  the  Cullasaja  river  and  the  Jackson  county  line,  an 
area  on  the  spurs  of  the  Cowee  mountains  is  thickly  dotted  with 
typical  oval  masses  of  normal  dunite,  of  which  the  well-known 
Corundum  Hill  outcrop  may  be  taken  as  an  example  (plate  IY). 
Many  of  the  masses  are  somewhat  larger  or  different  in  shape  from 
this,  but  the  variation  is  nowhere  very  great,  and  the  same  general 
type  prevails.  Plate  IY  is  a  topograhic  map  of  Corundum  Hill, 
and  shows  its  most  prominent  characteristics.  This  rather  blunt, 
lens-shaped  mass  of  dunite  has  an  extent  of  about  ten  acres,  and 
the  rock  is  laid  bare  over  almost  the  entire  surface.  Enstatite, 
which  is  developed  at  the  south  end  of  this  outcrop,  is  not  usually 
found  in  the  other  places  in  this  vicinity,  though  scattered  grains 
and  nodules  of  it  are  quite  common. 

As  indicated  on  the  map,  corundum  is  found  over  this  entire  area 
between  Walnut  and  Ellijay  creeks,  north  of  the  Cullasaja,  and 
considerable  activity  is  manifested  in  the  search  for  workable 
deposits. 

C.    JACKSON   COUNTY. 

In  the  line  of  strike  of  the  gneisses  of  the  Cullasaja  region,  are 
found,  in  Jackson  county,  a  series  of  long  strips  of  chlorite  schist, 
as  mentioned  in  the  description  of  that  rock,  in  the  vicinity  of  the 
forks  of  the  Tuckaseegee  river.  Similar  narrow  bands  of  talc 
schist  are  occasionally  seen  in  the  same  region. 

In  some  respects  the  dunite  area  at  Webster  (plate  Y)  is  the 
most  remarkable  outcrop  of  the  whole  Appalachian  belt.  In  point 
of  shape  it  is  entirely  unique,  bearing  no  resemblance,  as  a  whole, 
to  the  prevailing  lenticular  form.  The  line  of  outcrop  traces  an 
almost  unbroken  ellipse,  mostly  northeast  of  Webster,  with  a  major 
axis  of  six  miles  lying  north  25°  east,  and   a  minor   axis  of  three 


38 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


and  a  half  miles.  The  width  of  exposure  varies  from  a  third  of  a 
mile  at  Webster  to  extremely  attenuated  strips  of  talc  in  several 
places ;  and  on  the  eastern  side  five  complete  breaks  occur,  the 
smaller  disconnected  masses  having  the  typical  lenticular  form. 

Near  its  northern  extremity,  at  Addie,  an  irregular  mass  projects 
into  the  gneisses  within  the  ellipse;  and  a  little  further  west,  a 
gneiss  area  is  entirely  enclosed  by  slender  strips  of  dunite  and  talc. 
Near  Sylva,  on  the  western  side  of  the  area,  for  a  short  distance, 
the  deep  soil  covering  rendered  it  impossible  to  determine  whether 
the  belt  is  continuous  or  not  ;  and  hence  it  is  indicated  there  by  a 
dotted  line  on  the  map.  Plate  Y  is  reduced  from  a  map  of  this 
region  which  has  been  prepared  for  publication  in  the  final  report 
on  the  corundum  belt ;  but  the  most  prominent  features  alluded  to 
above  are  sufficiently  well  shown  as  not  to  require  further  explan- 
ation. 

Another  important  peculiarity  of  this  Webster  area  is  the  high 
development  of  lamination  ;  and  this  is  best  seen  in  the  larger  out- 
crops about  Webster  and  Addie.  In  its  broadest  portion,  on  the 
hillside  facing  the  river  at  Webster,  is  the  type  locality  of  web- 
sterite,  as  mentioned  in  the  description  of  that  rock.  It  forms  a 
strip  within  the  dunite  about  300  feet  wide  in  its  greatest  develop- 
ment, and  may  be  identified  for  a  distance  of  about  a  mile.  The 
only  other  locality  where  I  have  seen  this  rock  is  on  the  eastern 
side  of  this  ellipse,  about  a  mile  above  the  mouth  of  Cane  creek. 

The  peculiar  form  of  the  outcrop  renders  the  structure  of  this 
area  unusually  interesting.  The  strikes  conform  to  the  outline  of 
the  ellipse,  the  dips,  both  inside  and  outside,  are  away  from  the 
centre,  and,  in  general,  steeper  as  we  go  outward.  The  directions 
of  strike  and  dip  are  indicated  by  the  symbols  in  the  gneiss  area, 
near  the  borders  of  the  dunite. 

Near  the  head  of  Cane  creek,  and  within  half  a  mile  of  the 
isolated  dunite  masses  which  form  the  eastern  portion  of  the  Web- 
ster outcrop,  another  line  of  dunite  and  talc  schists  begins,  which 
is  continued  by  a  series  of  disconnected  masses  in  a  direction  north 
45°  east  almost  to  the  Haywood  county  line,  at  Balsam  gap.  Near 
the   gap,   a  very   coarse  grained  phase   is  developed,  which   bears 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  11,  PLATE  V. 


FIGURES   ON    CONTOUR    LINES    GIVE    ELEVATIONS    ABOVE    SEA    LEVEL 


DISTRIBUTION    OF    PERIDOTITES    AND    ASSOCIATED    ROCKS.  39 

enstatite  altered  to  talc,  and  good  exposures  are  seen  in  railroad 
cuts. 

In  the  southern  portion  of  Jackson  county,  several  small  danite 
areas  are  found  in  the  vicinity  of  Glenville,  and  associated  with 
these,  talc  and  chlorite  schists  are  developed  in  narrow  belts.  But 
dunite  is  found  in  much  greater  abundance  in  the  region  about 
Sapphire,  including  portions  of  both  Jackson  and  Transylvania 
counties. 

Directly  southwest  of  these  outcrops  and  in  the  direction  of  trend 
of  the  gneiss,  is  the  Laurel  creek  corundum  mine,  in  Rabun  county, 
Georgia.  This  mine  is  very  similar  in  many  respects  to  that  at 
Corundum  Hill.  The  dunite  outcrops  in  an  oblong,  somewhat 
irregular  mass,  covering  an  area  rather  larger  than  that  of  Corun- 
dum Hill ;  and,  so  far  as  observed,  no  arms  branch  off  into  the 
surrounding  gneiss.  The  nature  of  the  rocks  is  the  same,  though 
a  much  larger  development  of  enstatite  is  found.  The  principal 
differences  between  these  two  mines  are  found  in  the  minerals 
developed  with  the  corundum  ;  and  further  reference  will  be  made 
to  these  in  describing  the  modes  of  occurrence  of  corundum. 

Several  small  areas  of  dunite  and  talc  rocks  are  found  between 
the  State  line  and  Sapphire,  and  quite  a  large  area  in  the  vicinity 
of  the  latter  place  is  thickly  dotted  with  dunite  and  enstatite 
rocks.  Many  of  the  smaller  outcrops  are  necessarily  merged  into 
each  other  on  the  map. 

d.  Transylvania  county. 

In  the  southwestern  portion  of  the  county,  adjoining  the  Sap- 
phire region  of  Jackson,  the  rocks  are  the  same  as  those  mentioned 
above,  but  enstatite  rook  becomes  more  and  more  prevalent  as  we 
pass  northeastward  into  the  valley  of  the  upper  French  Broad 
river.  Often  the  surface  exposures  of  this  rock  are  entirely  altered 
to  talc,  and  all  the  northwestern  portion  represented  on  the  map 
by  the  talc-chlorite  symbol  is  composed  of  narrow  strips  of  talc 
schist,  seldom  exceeding  twenty  feet  in  width.  Those  nearer  Bre- 
vard are  similar  strips  of  chlorite,  becoming  quite  talcose  towards 
the  northeast.      They  are  made   up    of  several   outcrops   of  "soap- 


40 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


stone,"  as  it  is  called,  which  could  not  be  definitely  connected  by 
search  for  intervening  exposures  ;  but,  on  account  of  the  small 
scale,  they  have  been  thrown  into  continuous  lines  on  the  map. 

e.    HAYWOOD   COUNTY. 

From  the  crest  of  the  Balsam  mountains,  the  Haywood-Jackson 
county  line,  a  gap  occurs  in  the  peridotite  belt,  to  the  Pigeon 
river  above  Clyde — a  distance  of  15  miles.  Just  north  of  the 
river,  scattering  outcrops  of  soapstone  occur  over  an  area  of  sev- 
eral square  miles.  But  peridotite  does  not  appear  till  we  reach 
the  North  Fork  of  Hominy  creek,  two  and  a  half  miles  northeast 
of  Canton,  the  railroad  station  at  the  crossing  of  Pigeon  river. 
Here  a  strip  of  dunite  several  hundred  feet  wide  and  about  half  a 
mile  long  crosses  the  road  near  the  creek.  Another  small  lens 
occcurs  near  the  head  of  the  creek,  and  a  strip  of  talc  schist  and 
still  another  dunite  outcrop  is  found  in  New  Found  gap.  A  mile 
west  of  this  line  and  on  the  waters  of  North  Fork  is  the  amphib- 
olite  outcrop  in  which  is  located  the  Presley  corundum  mine. 

/.  buncombe;  county. 

For  a  distance  of  seven  miles  from  the  county  line  at  New  Found 
gap,  the  belt  is  not  represented  except  for  a  small  strip  of  talc 
which  extends  for  a  short  distance  from  the  dunite  at  the  gap. 
Near  Leicester,  where  the  Asheville  road  crosses  New  Found  creek, 
another  mass  of  dunite  occurs  with  dimensions  not  exceeding  thirty 
by  one  hundred  feet.  A  mile  southeast  of  this,  a  small  serpentine 
outcrop  about  ten  feet  wide  is  found  and,  very  near  this  another 
serpentine  mass  about  forty  feet  wide  and  about  half  a  mile  long. 

Less  than  a  mile  further  down  New  Found  creek,  two  outcrops 
are  found  about  150  feet  apart — one  a  strip  of  serpentine  ten  feet 
wide,  and  the  other  a  typical  dunite  about  thirty  feet  in  width. 
Both  of  these  outcrops  have  been  cut  across  in  search  of  nickel 
ore,  and  their  nature  is  well  shown.  Decayed  gneiss  appears 
between,  and,  as  far  as  the  outcrops  show,  the  two  masses  have  no 
connection  with  each  other. 


^ti&f&aa 


StaU  £#pi 


ar^t 


DISTRIBUTION    OF    PERIDOTITES    AND    ASSOCIATED    ROCKS.  41 

For  a  distance  of  eight  miles  from  this  point,  serpentine  and 
talc  are  the  only  basic  magnesian  rocks  found.  The  belt  crosses 
the  French  Broad  river  a  mile  above  Alexander — eight  miles  below 
Asheville — in  two  narrow  strips  of  serpentine  that  may  be  seen 
north  of  the  river  on  the  Asheville  road. 

The  river  gorge  here  shows  a  fine  section  of  the  gneiss.  It  con- 
tains many  granitic  and  other  igneous  intrusions  and  its  lamination 
planes  have  been  twis'ed  and  contorted  in  the  most  intricate  man- 
ner. Doubtless  the  forces  which  produced  these  phenomena  have 
had  great  influence  in  the  hydration  processes  that  produced  the 
serpentine  and  talc  in  the  dunite  belt  through  this  region. 

Through  the  Flat  Creek  mountains,  only  strips  of  talc  and  a  little 
serpentine  are  found,  except  one  small  outcrop  of  dunite  five  miles 
from  the  French  Broad  river,  near  the  head  of  Flat  creek.  The 
talc  outcrop  is  almost  if  not  quite  continuous  to  Morgan  hill,  two 
miles  south  of  the  Madison  county  line.  At  this  point,  it  connects 
directly  with  a  typical  dunite  mass  which  in  a  very  short  distance 
attains  a  width  of  400  to  500  feet,  and  is  continuous  with  about 
the  same  dimensions  for  three  miles,  ending  with  the  Carter  corun- 
dum mine  in  Madison  county. 

This  strip  is  remarkable  for  its  size  and  the  constancy  of  its 
characters  over  so  great  a  distance.  Most  of  it  is  laminated,  though 
less  so  than  that  of  Webster,  and  nickel  and  chrome  stains  are 
quite  prominent.  Talc  is  highly  developed  along  the  borders,  and 
chalcedony  is  found  in  rather  larger  quantities  than  usual.  Corun- 
dum has  attracted  attention  only  in  the  northern  portion  of  the 
outcrop,  beyond  Ivy  river;  and  important  deposits  have  been  found 
only  in  the  corner  of  Madison  county,  at  the  Carter  mine. 

The  second  parallel  strip  that  was  found  at  the  crossing  of  the 
French  Broad  river  is  still  traceable  in  the  narrow  strip  of  talc 
that  appears  at  intervals  from  half  a  mile  to  a  mile  east  of  the 
principal  outcrop. 

Q.    MADISON   COUNTY. 

The  Carter  corundum  mine  is  located  in  the  north  end  of  the 
outcrop  last  described,  which  is  continuous  from  Morgan  hill,  in 
Buncombe   county.      Three  miles  north   of  this,  serpentine  again 


42 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


appears  on  Paint  Fork  of  Ivy  river.  Light  green,  massive  rock 
predominates,  but  some  portions  show  a  considerable  amount  of 
unaltered  olivine  fragments  visible  to  the  naked  eye.  The  outcrop 
at  the  road  is  about  100  feet  wide  and  is  continuous  for  about 
three  miles  toward  Faint  gap.  At  one  point,  a  small  mass  of 
unaltered  dunite  occurs  about  one-eigth  of  a  mile  east  of  the  ser- 
pentine, having  a  width  of  about  fifty  feet  and  interlaminated  at 
the  borders  with  gneiss.  This  outcrop  shows  no  tendency  to  the 
development  of  massive  serpentine. 

The  second  and  minor  belt  is  represented  in  this  county  by  dark 
green  serpentine  on  the  head  waters  of  Terrys  Fork,  about  two 
miles  east  of  the  main  belt,  in  an  outcrop  about  200  feet  wide. 

Ten  or  twelve  miles  west  of  the  principal  peridotite  belt  just 
described,  is  a  zone  of  scattering  soapstone  outcrops,  which  crosses 
the  French  Broad  river  two  miles  below  Marshall.  This  zone 
seems  to  have  its  beginning  in  a  series  of  similar  rocks  found  north 
of  Clyde,  in  Haywood  county.  In  the  southern  part  of  Madison 
county,  soapstone  occurs  on  the  headwaters  of  Spring  and  Sandy 
Mush  creeks,  and  a  number  of  outcrops  are  found  along  the  course 
of  the  latter  within  a  few  miles  of  its  mouth.  It  appears  then  on 
Little  Pine  creek,  and  on  both  sides  of  the  French  Broad  river 
below  Marshall.  Outcrops  occur  at  intervals  as  we  pass  up  Wal- 
nut  creek,  and  in  a  number  of  places  on  the  waters  of  Big  Laurel 
creek,  on  the  north  side  of  the  county. 

The  chief  constituent  of  these  outcrops  is  schistose  talc  with 
more  or  less  chlorite,  the  latter  in  a  few  places  predominating,  or 
occurring  almost  pure.  But  one  important  exception  was  found  to 
this  rule,  and  that  is  an  outcrop  two  miles  north  of  Marshall,  on 
Walnut  creek,  at  the  county  poor-house.  The  rock  here  consists 
largely  of  talc  also  ;  but  scattered  thickly  through  it  are  grain:  and 
crystals  of  olivine,  varying  in  size  from  a  small  fraction  of  an  inch 
to  one  or  two  inches  in  diameter.  A  rock  exactly  similar  to  this, 
near  Philadelphia,  except  that  the  olivine  has  largely  altered  to 
serpentine,  has  been  called  "perido-steatite"  Several  of  the  soap- 
stone  outcrops  in  this  Madison  county  zone  are  full  of  small  "rust- 
holes,"  as  though  similar  olivine  crystals  had  weathered  out  of  it. 


DISTRIBUTION    OF    PERIDOTITES    AND    ASSOCIATED    ROCKS.  43 

7l.    YANCEY   COUNTY. 

Crossing  the  mountains  about  Paint  gap,  only  talc  schists  repre- 
sent the  belt  till  near  Cnney  river  the  serpentine  is  again  found  on 
Possum  Trot  (McElroys)  and  Bald  creeks. 

Here  it  has  the  same  general  characters  as  that  on  Paint  Fork, 
and  the  outcrops  indicate  masses  of  approximately  the  same  dimen- 
sions. Beyond  Caney  river,  no  direct  extension  of  this  line  is 
known,  but  two  miles  to  the  eastward,  irregular  outcrops  of  dunite 
occur  on  the  waters  of  Prices  and  Banks  creeks,  accompanied  by 
a  little  serpentine  and  a  narrow  strip  of  chlorite  schist.  Small 
talc  outcrops  are  also  found  on  the  Green  mountains  north  of 
Burnsville. 

Four  miles  north  of  Burnsville,  on  Mine  Fork  of  Jacks  creek,  a 
very  prominent  lenticular  mass  of  peridotite  appears.  It  is  about 
half  a  mile  long  and  500  feet  wide,  and  forms  two  small  hills,  one 
on  either  side  of  the  creek.  The  rock  is  normal  harzburgite  of 
greenish  yellow  color,  rather  plentifully  sprinkled  with  chromite 
grains,  and  much  of  it  contains  talc  scales  of  the  form  and  appear- 
ance of  the  original  enstatite.  A  small  peridotite  mass  occurs 
half  a  mile  north  of  this,  and  then  the  line  of  outcrop  swerves  sud- 
denly eastward,  just  before  reaching  the  Toe  river.  For  the  rest 
of  the  distance  within  the  county,  it  is  represented  only  by  narrow 
talc  strips  and  occasionally  a  little  serpentine. 

A  still  smaller  belt  appears  to  the  east  of  this  line  of  principal 
outcrops,  and  this  is  seen  in  a  narrow  talc  strip  about  two  miles 
northeast  of  Burnsville,  and  in  a  mass  of  dunite  on  Chestnut 
mountain,  four  miles  east  of  the  locality  on  Mine  Fork  described 
above. 

This  last  locality  is  perhaps  the  purest  type  of  olivine  rock  yet 
observed  in  the  whole  belt.  The  outcrop  is  about  300  by  700  feet, 
oval  in  shape,  and  forms  a  hill  about  200  feet  high,  with  a  per- 
fectly barren  rocky  surface  except  for  occasional  bunches  of  sedge 
that  grow  in  the  crevices  of  the  rocks.  The  longer  axis  of  this 
mass  lies  north  10°  west.  Besides  light  greenish  yellow  olivine,  the 
rock  contains  only  a  few  disseminated  scales  of  chlorite  and,  in 
places,  small  flecks  and  interlacing  veins  of  talc.      The  rock  lias 


44 


CORUNDUM    AND    BASIC    MAGNESIAX    ROCKS. 


weathered  to  a  dull  brown  on  the  surface,  but  shows  very  little 
alteration  of  any  other  kind.  At  the  contact  with  the  mica  schist 
in  which  it  is  enclosed  there  is  a  radial  border  of  fibrous  enstatite 
altered  mostly  to  talc,  but  such  borders  do  not  follow  the  joints 
within  the  mass,  as  is  often  the  case  in  other  localities. 

Ten  miles  west  of  Burnsville,  in  Egypt  township,  on  the  slopes 
of  Sampson  and  Bald  mountains,  occurs  a  strip  of  rocks  that  must 
be  considered  as  belonging  here.  At  its  southern  extremity  is 
located  the  Hayes  (or  Egypt)  corundum  mine,  and  the  predominant 
rock  is  enstatite  with  a  little  dunite,  the  latter  considerably  altered 
to  tremolite.  Three  separate  masses  of  enstatite  rock  occur  at  the 
mine,  and  the  line  of  outcrop  is  almost  continuous  across  Bald 
Mountain  creek.  From  this  point  narrow  talc  strips  were  found 
northward  for  a  distance  of  four  miles. 

Again,  on  the  eastern  border  of  the  county,  we  find  a  belt  of 
enstatite  rocks,  and  talc  resulting  from  their  hydration,  along  the 
valley  of  the  South  Toe  river.  Six  miles  south  of  the  forks  of  Toe 
river,  corundum  is  found  with  one  of  these  outcrops  on  Bailey 
mountain.  A  mile  east  of  this,  there  is  a  large  outcrop  of  the 
talc-olivine  rock  ("perido-steatite")  described  above  (see  Madison 
county).  The  olivine  crystals  in  this  case  are,  however,  much 
larger,  some  of  them  being  several  inches  in  diameter. 

I.    MITCHEI.I,  COUNTY. 

Eight  miles  south  of  Bakers ville,  and  just  north  of  the  ford  of 
South  Toe  river,  is  an  outcrop  about  one-fourth  of  a  mile  long  and 
300  to  400  feet  wide,  composed  chiefly  of  dunite,  though  there  is 
also  considerable  enstatite  rock ;  and  forming  the  transition 
between  these  two  types,  harzburgite  is  developed.  This  locality 
is  very  similar  to  that  at  the  Woody  place  described  next  below. 

Two  and  a  half  miles  south  of  Bakersville  is  a  large  lenticular 
outcrop  of  dunite  on  what  is  known  as  the  Woody  place.  It  is 
about  300  by  600  feet  and  the  long  axis  lies  north  65°  east.  It  is 
a  light  green  dunite  with  considerable  masses  of  enstatite  rock. 
Very  little  chromite  was  seen.  Cellular  and  compact  chalcedony 
and  nickel  stains  are  abundant.  The  hillside  which  is  composed  of 
this  rock  is  quite  barren  and  rocky. 


DISTRIBUTION    OF    PERIDOTITES    AND    ASSOCIATED    ROCKS.  45 

From  this  place  a  line  of  enstatite  and  talc  rocks,  outcropping  at 
frequent  intervals,  extends  up  Cane  creek.  One  small  dunite 
mass  appears  near  the  summit  of  Grassy  Ridge  Bald,  considerably 
to  the  north  of  the  general  line;  but  the  original  direction  is  con- 
tinued by  the  large  outcrops  on  North  Toe  river,  six  miles  south 
of  Cranberry,  near  the  mouth  of  Roaring  creek.  This  is  a  large, 
irregular  area  which  is  continuous  for  nearly  a  mile  with  a  width 
of  150  to  200  feet, 

Considerable  chromite  is  found  in  some  portions  of  the  rock, 
and  chrysotile  (fibrous  serpentine,  commonly  called  asbestos)  is 
highly  developed  at  the  north  end  of  the  exposure,  just  below  the 
mouth  of  Squirrel  creek.  Another  area  of  dunite  occurs  near  this, 
on  the  side  of  Haw  mountain. 

At  Bellevue,  on  the  summit  of  Fork  mountain,  two  miles  south 
of  Cranberry,  dunite  also  appears  in  an  outcrop  abolit  200  feet 
wide  and  greatly  altered  to  serpentine  and  talc.  The  outcrop  can 
be  traced  by  a  strip  of  the  latter  for  about  one-fourth  of  a  mile. 

But  here  we  evidently  encounter  the  results  of  very  great  and  com- 
plex earth  movements,  as  shown  by  the  manner  in  which  the  rocks 
of  the  Ocoee  formation  have  sufferen  folding,  crumpling  and  gen- 
eral breaking  up  ;  and  also  by  the  presence  of  considerable  bodies 
of  massive  rocks.  In  this  region  of  intense  confusion,  no  recogniz- 
able peridotites  or  related  rocks  have  been  observed  for  a  distance 
of  about  sixteen  miles  from  the  outcrop  at  Bellevue  mentioned 
above. 

j.    WATAUGA   COUNTY. 

Normal  conditions  are  somewhat  restored  in  the  upturned  edges 
of  the  gneisses  on  the  western  side  of  Rich  mountain,  just  north  of 
Boone.  The  first  appearance  of  peridotite  is  observed  in  the  road 
about  two  and  a  half  miles  west  of  Boone,  where  atypical  yellow- 
ish dunite  appears  in  a  small  outcrop.  From  this  point  outcrops 
occur  at  intervals  in  a  curved  line  following  the  general  trend  of 
the  mountain  for  a  distance  of  four  miles  northward.  More  or  less 
talc  and  asbestos  accompany  these  occurences. 

Near   where   the    road  crosses   the   mountain    at   the  northern 
extremity  of  this  line,  a  considerable  body  of  chromite   has   been 


46 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


removed  in  prospecting.  It  was  in  the  form  of  a  lenticular  mass 
lying  in  the  pure  olivine  rock,  narrowing  within  a  few  feet  of  the 
surface  to  a  small  vein.  These  places  constitute  the  last  dunite 
outcrops  found  on  the  belt  within  the  State.  Further  northward, 
enstatite  becomes  a  predominating  element,  as  in  the  region  about 
Sapphire,  in  Jackson  county,  and  in  a  number  of  cases  constitutes 
the  whole  mass  of  the  rock. 

Just  east  of  the  northern  extremity  of  this  Eich  mountain  dunite, 
and  about  four  miles  north  of  Boone,  an  enstatite  rock  is  encoun- 
tered— in  places  altered  into  talc  on  the  surface — forming, 
in  some  cases,  masses  of  a  hundred  feet  or  more  in  width  and 
traceable  across  the  country  continuously  for  about  two  miles. 
Other  areas  of  less  importance  are  indicated  on  the  map,  but  it  is 
scarcely  necessary  to  mention  them  all  in  detail. 

Of  the  other  areas  indicated  on  the  map,  one  six  miles  east  of 
Boone,  on  the  crest  of  the  Blue  Ridge  just  north  of  Cook  gap,  is 
worthy  of  mention.  Talc,  bearing  fine  radiating  actinolite,  is  the 
predominant  rock  in  an  outcrop  about  fifty  feet  wide  and,  per- 
haps, three  or  four  times  as  long.  But  there  are  also  large  masses 
of  dark  green  serpentine,  the  only  occurrence  of  this  rock  that  I 
have  found  north  of  Cranberry.  About  one-fourth  of  a  mile  north- 
east of  this,  another  outcrop  of  soapstone  of  about  the  same  dimen- 
sions is  found  on  the  estern  slope  of  the  Blue  Hidge. 

k.  ASHE   COUNTY. 

An  outcrop  of  importance,  both  on  account  of  its  unusual  size 
and  the  type  of  rock  represented,  is  found  on  the  middle  fork  of 
Elk  creek  three  miles  from  its  mouth,  and  situated  just  east  of  the 
Watauga  county  line.  Here  an  immense  mass  of  harzburgite,  the 
olivine-enstatite  peridotite,  forms  heavy  cliffs  on  the  western 
slope  of  Black  mountain,  and  great  quantities  of  it  have  rolled 
down  into  the  creek  below.  The  rock  consists  of  about  equal 
parts  of  enstatite  and  olivine,  and  the  texture  varies  from  a  uni- 
form fine  grain  to  that  in  which  both  constituents  assume  dimen- 
sions of  three  or  four  inches.  Blocks  of  scaly  chlorite,  bearing 
red  garnets  one-fourth  of  an  inch  in  diameter  and  occasional  crys- 
tals of  magnetite,  are  also  found. 


DISTRIBUTION    OF    PERIDOTITES    AND    ASSOCIATED    ROCKS.  47 

Four  miles  northeast  of  the  outcrop  just  described,  is  another 
great  mass  of  harzburgite,  on  Bee  Ridge,  a  short  spur  on  the  east 
side  of  Elk  Ridge.  The  mass  is  about  a  thousand  feet  wide,  length 
undetermined,  and  presents  a  forked  outline  at  the  south  end. 
Enstatite  frequently  predominates,  and  soapstone  derived  from  it 
constitutes  about  half  of  the  outcrop.  This  is  sometimes  schis- 
tose, though  it  often  retains  the  structure  of  the  mineral  from 
which  it  is  derived.  Considerable  quantities  of  this  stone  have 
been  used  for  furnace  linings  in  the  copper  works  at  Ore  Knob. 
In  the  surrounding  country,  most  of  the  fireplaces  and  many  of 
the  chimneys  are  built  of  it  ;  and  it  is  found  quite  suitable 
for  these  purposes,  both  on  account  of  its  fireproof  qualities  and 
the  ease  with  which  it  is  worked.  Soapstone  outcrops  have  been 
worked  at  intervals,  along  the  flanks  of  Elk  Ridge,  for  three  or 
four  miles  north  of  this  place. 

Other  small  outcrops  of  soapstone,  which  have  had  some  local 
application,  are  found  on  Negro  mountain,  just  south  of  Jefferson, 
and  one  and  a  half  miles  north  of  Jefferson,  at  Phoenix  gap. 

I.    AUEGHANY  COUNTY. 

The  first  appearance  of  peridotite  in  this  county  is  found  three 
miles  south  of  Sparta,  near  Little  river,  where  soapstone  is  found 
in  the  road  to  Whitehead.  From  this  point,  a  line  of  disconnected 
harzburgite  outcrops  follows  the  general  direction  of  Little  river 
almost  to  the  Virginia  line.  It  is  typically  developed  about  a 
mile  east  of  the  mouth  of  Pine  Swamp  creek,  also  just  north  of 
the  mouth  of  Glade  creek,  in  the  great  bend  of  the  river,  and 
south  of  the  river,  at  the  mouth  of  Brush  creek.  It  next  appears 
at  Ennis,  on  Crab  creek,  and  is  found  in  almost  a  continuous  line 
up  the  north  fork  of  this  creek,  in  a  direction  about  north  50° 
east,  to  the  Virginia  line.  The  same  rock  is  said  to  occur  almost 
continuously  for  fifteen  miles  further  in  the  same  direction. 

This  rock  has  about  the  same  nature  as  that  at  Bee  Ridge,  in 
Ashe  county,  described  above.  All  stages  are  found  between  pure 
talc  and  nearly  pure  olivine  rock,  but  the  latter  is  never  quite 
free  from  a  certain  perceptible  amount  of  talc  or  enstatite.  A 
coarse  lamination  is  generally  discernible,  and  the   purer   steatite 


/ 


48 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


portions  are  usually  schistose.  The  latter  also  frequently  bears  a 
considerable  proportion  of  carbonates;  and  the  numerous  "rust- 
holes"  in  some  portions  of  the  outcrops  are  doubtless  due  to  the 
weathering  out  of  these  minerals  and  olivine. 


6.     CORUNDUM. 


For  a  complete  description  of  the  chemical,  physical,  and  crys- 
tal lographic  characters  of  corundum,  the  reader  is  referred  to 
Dana's  System  of  Mineralogy,  or  to  any  good  text-book  on  the 
subject.  Only  the  most  important  features  are  related  here,  and 
technicalities,  while  not  entirely  avoidable,  are  dispensed  with  or 
explained  as  far  as  practicable,  for  the  benefit  of  the  general 
reader. 

(1.)    CHARACTER    AND    VARIETIES. 

Next  to  diamond,  corundum  is  the  hardest  substance  known  in 
nature,  and  on  this  property,  as  more  or  less  modified  by  other 
qualities  named  below,  depends  its  commercial  value.  It  crystal- 
lizes in  the  rhombohedral  division  of  the  hexagonal  system  ;  but 
the  six-sided  prism  is  usually  the  most  prominent  form,  and  the 
crystals  often  appear  to  have  the  complete  hexagonal  symmetry 
(see  figures  1,  2  and  3).  Sometimes,  however,  the  rhombohedron  is 
quite  prominent,  but  it  is  usually  developed  only  in  small  faces 
truncating  the  alternate  corners  of  the  prism  and  basal  plane  or 
pyramid. 

Small  crystals  are  usually  quite  perfectly  formed,  but  the 
larger  ones  are  generally  rough  and  irregular,  with  many  of  the 
faces  deeply  corrugated.  Figures  1  and  2  show  the  hexagonal 
form  as  effected  by  rhombohedral  and  basal  parting,  respectively. 
Figure  3  is  a  crystal  with  rhombohedral  parting  well  shown  by 
the  faces  it  has  produced  on  the  prism.  Figure  8  is  a  common 
form  of  wrapped  crystal. 

Strictly  speaking,  corundum  has  no  cleavage,  but  two  forms  of 
parting,  often  erroneously  called  cleavage,  are  frequently  met 
with.     This  parting  is  due  to  multiple  twinning,    and  the  form 


CORUNDUM CHARACTER    AND    VARIETIES. 


49 


most  commonly  seen  is  that  parallel  to  the  rhombohedral  faces, 
which  are  inclined  to  each  other  at  an  angle  of  93°  56r,  thus 
breaking  the  crystal  into  almost  cubical  blocks,  (see  figures  1,  3,  and 
7).  The  other  form  of  parting  is  parallel  to  the  basal  plane,  and 
crystals  in  which  it  is  developed  break  square  across  into  a  number 
of  thin  segments,  often  resembling  buttons,  (figure  2).  Crystals 
or  masses  in  which  no  parting  is  developed  break  with  a  rough, 
uneven  fracture. 


Fig.  1. 


Fit 


Fh 


Fig.  1.— Hexagonal  crystal  of  corundum  showing  rhombohedral  parting.  (From 
Tschermak's  Mineralogy.) 

Fig.  2,— Corundum  crystal  showing  basal  parting  and  concentric  zonal  arrangement  of 
colors.    (Tschermak.) 

Fig  3.— Corundum  crystal  from  Egypt  mine,  Yancey  county,  showing  hexagon  termi- 
nated by  rhombohedral  parting  planes.  One-fourth  natural  size.  (Drawn  from  a  photo- 
graph.) 


Corundum  sometimes  appears  in  masses  without  crystal  form, 
though  crystalline  in  structure,  and  such  masses  may  have  either 
form  of  parting  described  above.  Crystalline  granular  aggregates 
are  also  sometimes  met  with. 

All  the  foregoing  varieties  of  form  and  crystallization  are 
subject  to  great  variation  in  color — gray,  blue  and  red  being  the 
most  common.  Corundum  is  usually  more  or  less  translucent,  but 
seldom  transparent.  The  more  strongly  colored  varieties  are 
pleochroic;  that  is,  they  show  different  colors  for  light  passing- 
through  them  in  different  directions. 

Corundum  has  a  specific  gravity  of  3.9  to  4.1,  which  is  equiva- 
lent to  saying  that  it  is  about  four  times  as  heavy  as  water.  Of  the 
minerals  associated  with  it,  only  chromite  and  magnetite  are 
heavier,  garnet   and  spinel   are   about  the   same   weight;   olivine, 


50 


CORUNDUM    AND    BASIC    MAGNESIAN    BOOKS. 


chlorite,  hornblende,  tourmaline  and  margarite  are  not  so  heavy; 
while  quarty,  feldspar,  serpentine,  and  talc  are  much  lighter. 

Professor  Dana,  in  his  description  of  the  varieties  of  corundum, 
says  :  "There  are  three  subdivisions  of  the  species  prominently 
recognized  in  the  arts,  and  until  early  in  this  century  regarded  as 
distinct  species  ;  but  which  actually  difTer  only  in  purity  and  state 
of  crystallization  or  structure."* 

The  three  varieties  mentioned  are ;  1.  Sapphire,  2.  Corundum, 
3.   Emery. 

1.  Sapphire  includes  all  those  transparent  and  translucent  kinds 
which  are  of  good  colors  and  useful  as  gems.  Jewelers  designate 
the  various  gems  according  to  colors  :  the  red  is  the  oriental  or 
true  ruby  ;  the  blue  is  the  sapphire;  the  yellow  is  the  oriental 
topaz  ;  the  green  is  the  oriental  emerald  /  the  purple,  the  oriental 
amethyst ;  and  the  opalescent  variety  showing  a  six-rayed  star  of 
light  is  called  asteria,  or  star  sapphire.  North  Carolina  has  pro- 
duced the  sapphire  variety  of  corundum  in  every  known  color. 

2.  Corundum,  as  the  term  is  used  in  the  arts,  "  includes  the 
kinds  of  dark  or  dull  colors  and  not  transparent,  colors  light  blue 
to  gray,  brown  and  black."  This  is  the  rough  material  which 
forms  the  bulk  of  the  product  of  the  North  Carolina  mines. 

3.  Emery  is  an  intimate  mixture  of  granular  corundum  and 
magnetite  or  hematite.  This  is  the  form  of  much  the  greater  part 
of  the  corundum  used  in  the  arts  ;  a  fact  which  is  due  to  its  com- 
parative abundance  and  cheapness  in  Asia  Minor  and  the  Grecian 
Islands,  while  corundum  is  obtainable  only  in  much  smaller  quan- 
tities and  at  greater  expense.  Emery  is  mined  at  Chester, 
Massachusetts,  and  has  been  obtained  in  small  amounts  from 
Westchester  county,  New  York.  It  was  found  in  Guilford  county, 
North  Carolina,  in  1871,  by  Dr.  Genth,  (see  index  reference, 
.Emery),  and  has  been  recently  reported  from  a  locality  in  Macon 
county,  North  Carolina,  but,  so  far  as  I  am  aware  the  material  has 
not  yet  been  examined,  so  no  further  statement  can  be  made  in 
regard  to  it  at  present. 


'Dana's  System  of  Mineralogy,  1892,  page  212. 


j*}iai9  %j/{hi»&?2» 


USES    OF    CORUNDUM.  51 


(2.)  USES  OF  CORUNDUM. 

The  use  of  the  sapphire  variety  for  gems  has  already  been 
pointed  out  in  the  description  above.  The  red  colors  are  most 
highly  prized  for  this  purpose,  and  especially  that  particular 
shade  known  as  "pigeon-blood."  Fine  specimens  of  two  or  three 
carats  in  weight  are  equal  in  value  to- the  diamond. 

Corundum  and  emery  are  used  for  the  same  purposes,  and  in 
both  the  value  is  due  to  the  hardness  as  applied  to  cutting  and 
polishing  metals,  glass,  stone,  and  all  hard  substances.  The  mate- 
rial to  be  used  for  polishing  is  first  crushed  and  then  sorted 
according  to  size  of  grain  by  passing  through  sieves.  For  most 
cutting  and  grinding  purposes,  the  granular  material  thus  obtained 
is  made  into  a  kind  of  dough  with  some  cementing  material,  then 
moulded  into  the  form  of  a  grindstone  and  baked.  Such  artificial 
stones  are  called  corundum  wheels  or  emery  wheels,  according  to 
the  material  of  which  they  are  made,  and  are  extensively  used  in 
all  kinds  of  metal  working,  especially  the  iron  and  steel  industries. 

(3.)    NORTH    CAROLINA    CORUNDUM. 

The  gem  varieties  of  corundum  were  the  chief  attraction  for 
the  early  prospectors  and  miners.  The  mine  at  Corundum  Hill, 
in  Macon  county,  the  story  of  which  constitutes  the  greater  part 
of  the  history  of  corundum  mining  in  the  United  States,  was 
opened  and  worked  for  a  number  of  years  as  a  gem  mine.  Some 
of  the  material  that  came  from  this  mine  and  other  localities  in 
the  State  has  attracted  considerable  attention,  as  may  be  seen  from 
the  following  mention  by  Mr.  George  F.  Kunz : 

"In  variety  of  color  the  North  Carolina  corundum  excels.  It  is 
found  gray,  green,  rose,  ruby-red,  emerald-green,  sapphire-blue, 
dark  blue,  violet,  brown,  yellow,  and  of  intervening  shades,  and 
colorless"  "Many  specimens  [from  North  Carolina]  have  been 
cut  and  mounted,  especially  of  the  blue  and  red  shades,  and  make 
good  gems,  though  not  of  the  choicest  quality.  Several  rubies  of 
1  carat  each  have  been  found  ;  a  blue  sapphire,  1  carat  in   weight, 


/ 


52 


CORUNDUM    AND    BASIC    MAGNESIAN    BOCKS. 


is  in  the  United  States  National  Museum  at  Washington,  and  a 
series  of  fine  red  and  bine  crystals  has  been  deposited  there  by 
Dr.  H.  S.  Lucas."* 

In  several  localities,  as  on  Ellijay  creek,  in  Macon  county,  crys- 
tals of  a  peculiar  brown  corundum  with  a  beautiful  chatoyant 
lustre  have  been  found.  "These  (when  cut  en  cabochon)  all  show 
a  slight  bronze  play  of  light,  and  under  artificial  light  they  show 
well  defined  stars,  being  really  asterias,  or  star-sapphires,  and  not 
cat's  eyes,  as  might  seem  at  first  sight  to  be  the  case."f 

Although  the  principal  work  in  the  mining  region  is  now  con- 
centrated on  the  search  for  commercial  corundum,  still  there  is  a 
considerable  interest  shown  in  some  sections  in  prospecting  for 
gems;  and  Mr.  Kunz  writes  again  in  1893:  "The  finding  of  small 
rubies  of  fairly  good  color  in  Macon  county,  North  Carolina,  gives 
ground  for  the  belief  that  larger  and  better  stones  may  be  found 
there  by  more  extended  development."^:  • 

Commercial  corundum  does  not  occur  in  all  the  varieties  of  color 
that  are  found  in  the  gems,  but  there  are  differences  of  texture  and 
purity  that  have  no  less  important  bearing  on  the  value  of  the  pro- 
duct than  color  and  transparency  in  the  gems.  As  mentioned 
above  in  describing  the  varieties,  this  class  includes  all  those  dull  and 
dark  colored  kinds  which  constitute  the  priucipal  product  of  the 
mines.  The  colors  are  generally  gray,  or  some  shade  of  blue,  or  mot- 
tled white  and  blue;  but  the  variations  in  texture  are  much  more 
important  than  those  of  color.  The  different  mines  of  the  State 
produce  every  known  variety  :  massive  or  "block"  corundum,  crys- 
tal corundum,  and  the  fine  granular  or  crystalline  variety  called 
"sand"  corundum.  And  all  these  are  sometimes  found  associated 
in  the  same  immediate  locality  or  even  the  same  mine.  Each 
mine  has  its  own  peculiar  characteristics,  however,  and  a  kind  of 
family  resemblance  runs  through  its  whole  product.  This  fact  is 
well  recognized  by  the  miners,  and  they  can  frequently  ascribe  a 
specimen  to  its  proper  locality  by  its  general  appearance. 

Corundum  from  some  localities  is  chiefly  six  sided  crystals,  often 


*George  F.  Kunz,  Mineral  Besources  of  the  United  States,  1892,  pages  760,  761. 
tGeorge  F.  Kunz,  Gems  and  Precious  Stones  of  North  America,  1890,  page  47. 
^George  F.  Kunz,  Mineral  Besources  of  the  United  States,  1893,  page  680. 


NORTH  CAROLINA  CORUNDUM.  53 

tapering  toward  the  end  like  a  barrel — hence,  we  sometimes  hear  the 
term  "barrel  corundum" — and  these  crystals  may  or  may  not 
have  one  of  the  forms  of  parting  developed.  If  parting  is  absent 
or  only  developed  to  a  slight  extent,  the  crushed  product  will  be 
solid  and  tough,  even  in  the  coarser  numbers;  while,  if  it  is  very 
highly  developed,  the  coarse  numbers  and  sometimes  also  the 
medium  and  finer  sizes  will  be  full  of  these  parting  planes  along 
which  it  will  easily  crumble  down  in  use.  Besides  producing  a 
defective  grain,  there  is  always  considerable  loss  in  crushing  from 
the  production  of  an  unusual  amount  of  "flour." 

The  massive  or  "block"  corundum  may  have  the  same  defects, 
though  this  is  usually  not  the  case,  and  hence  such  material,  when 
in  sizes  suitable  for  crushing,  produces  a  good  tough  grain.  But 
the  difficulty  encountered  in  working  such  corundum  lies  in  the 
size  of  the  masses,  which  are  frequently  intergrown  with  feldspar 
and  hornblende  into  blocks  so  tough  that  they  cannot  be  profitably 
broken  and  crushed.  This  is  the  case  with  some  of  the  material 
mined  at  Buck  creek,  in  Clay  county.  This  variety  is  also  found 
in  veins  of  tough,  compact  materials  which  render  its  removal  from 
the  mine  a  source  of  considerable  expense. 

Sand  corundum  consists  of  small  crystals  and  irregular  grains, 
which  are  developed  in  the  soft  vermiculites  surrounding  the 
peridotites,  and  hence  are  always  easily  dug  out  and  the  corundum 
obtained  by  washing  away  the  lighter  minerals.  This  variety  is 
not  subject  to  the  difficulties  and  defects  of  the  other  two,  but,  as 
there  is  considerable  variation  in  the  size  of  the  grains,  it  is  impos- 
sible to  remove  all  the  lighter  minerals  by  washing,  and,  of  course, 
the  magnetite  and  chromite  cannot  be  thus  removed. 

Corundum  in  place  in  the  rocks  is  subject  to  numerous  altera- 
tions by  which  its  hardness  is  impaired  even  in  incipient  stages  ; 
and  this  property  is  entirely  lost  in  the  complete  alteration, 
which  produces  a  series  of  aluminous  minerals  of  little  or  no  value 
as  abrasives. 

It  is  a  well  known  fact  that  chemical  action  takes  place  much  more 
rapidly  on  small  grains  than  on  large  ones,  owing  to  the  greatly 
increased  proportion  of  surface  exposed:  hence,  sand  corundum  is 
more  subject  to  alteration  than  the  larger  masses.      The  sand  may 


51  CORUNDUM    AND    BASIC    MAGNESIAS'    ROCKS. 

be  in  some  cases  only  the  remnants  of  larger  masses  which  have 
disappeared  through  this  means.  Still,  sand  corundum  is  the  kind 
most  sought  by  the  miners,  and  the  usnal  presence  of  more  or  less 
crystal  corundum  along  with  it  makes  up  to  a  certain  extent  for 
its  lack  of  purity.  These  two  forms  constitute  the  product  of  the 
mine  at  Corundum  Hill. 

(4.)  MODES  OF  OCCURRENCE  OF  CORUNDUM. 

Professor  Zirkel  enumerates  the  following  modes  of  occurrence 
of  corundum  as  a  rock  constituent'.  Corundum  in  small,  fine 
grained  aggregates  is  the  chief  constituent  of  emery.  Otherwise,  it 
occurs  only  occasionally  as  an  accessory  in  granites,  gneisses,  granu- 
lar limestones  and  dolomites,  in  the  amphibolites  of  northwestern 
Austrian  Silesia  (largest  hazel-nut  size,  white  or  blue  grains  i, 
in  the  cholorite  schist  of  Nischne-Issetsk  in  the  Urals,  in  the  graph- 
ite of  Miihldorf,  near  Spitz,  in  Lower  Austria ;  as  blue  sapphire 
in  several  basalts,  where  it  is  perhaps  originally  a  remnant  of  mol- 
ten inclusion;  often  with  spinel,  rutile  and  sillimanite.  Worthy 
of  note  is  the  occurrence  as  a  contact  product  of  the  diorites  of 
Klausen,  in  Tyrol.  It  is  also  observed  as  altered  foreign  inclu- 
sions or  as  real  accessory  masses  in  certain  eruptive  rocks,  often 
with  cordierite,  spinel,  andalusite — as  inclusions  in  the  andesite 
of  the  Eifel,  and  similarly  in  tonalite.  Further  it  appears  scattered 
through  a  contact  product  of  qnartz-mica-diorite  on  quartz-phyl- 
lite  in  Yal  Moja.  Similarly  in  the  kersantite  of  Mickaelstein, 
Harz.* 

Besides  these  occurrences  as  a  rock  constituent,  corundum  is 
found  in  large  quantities  in  feldspar  veins  and  associated  with  clilo- 
rites  in  the  peridodtites  and  serpentines  of  the  Atlantic  States 
of  America  ;  and  in  areas  of  crystalline  rocks  in  many  parts  of  the 
earth's  surface,  in  the  gravel-beds  of  streams.  Except  the  occur- 
rences in  granular  limestone,  in  graphite,  and  in  association  with 
volcanic  rocks,  all  the  various  modes  enumerated  above  have  been 
observed  in  North  Carolina.  These  will  be  described  briefly  in  the 
following  order: 

*F.  Zirkel,  Lehrbuch  der  Petrograptiie,  Leipsic,  1893,  page  416. 


CORUNDUM    ASSOCIATED    WITH    PERIDOTITES.  55 

a.  Associated  with  peridotites ;  h.  In  chlorite  schist ;  c.  In 
amphibolite  ;  d.  In  dunite ;  e.  In  gneiss ;  f.  In  gravel  deposits. 

a.    CORUNDUM   ASSOCIATED   WITH   PERIDOTITES. 

The  occurence  of  corundum  in  the  State,  with  few  important 
exceptions,  is  in  association  with  olivine  rocks  (peridotites),  though 
rarely  occurring  in  the  body  of  such  rocks.  It  is  found  in  the 
zone  of  chlorites  and  vermicnlites  developed  between  the  perido- 
tites and  the  gneisses  of  the  surrounding  country,  and  sometimes 
near  this  zone  in  the  gneisses  themselves.  In  some  cases  this 
border  zone  of  chloritic  minerals  carrying  corundum  has  de- 
veloped along  -the  joints  of  the  peridotites  to  the  very  center  of 
the  mass.  Such  a  condition  is  shown  in  a  number  of  openings  at 
.Corundum  Hill,  though  mining  operations  have  been  chiefly  con- 
fined to  the  border  zones.    (See  figure  6.) 

These  zones  vary  exceedingly  in  thickness,  from  ten  or  twelve 
inches  to  as  many  feet,  and  the  proportion  of  corundum  is  scarcely 
more  constant,  though  bearing  no  relation  to  the  dimensions  of 
the  "vein".  In  places  the  chlorites  are  thickly  studded  with  cor- 
undum almost  from  wall  to  wall,  and  sometimes  this  condition 
prevails  for  a  considerable  distance;  then  the  corundum-bearing 
portion  wTill  narrow  down  to  a  thin  strip  in  the  middle,  or  perhaps 
disappear  entirely,  to  be  encountered  again  only  after  a  consider- 
able amount  of  barren  material  has  been  handled. 

There  is  a  prevailing  impression  that  peridotite  always  occurs 
in  hornblende-gniess.  While  this  is  frequently  the  case  it  is  by 
no  means  universally  true,  as  a  microscopic  examination  shows  some 
of  these  enclosing  rocks  to  be  normal  gneiss  ;  that  is,  composed 
of  quartz,  feldspar  and  mica  (the  mica  being  chiefly  biotite).  In 
other  cases,  the  country  rock  is  mica-schist. 

A  gneissoid  rock  resulting  from  the  lamination  of  the  bright 
green  hornblende  rock  found  at  Buck  creek,  in  Clay  county,  and 
elsewhere,  is  closely  associated  with  the'  peridotites  of  these  local- 
ities;  but  it  is  here  regarded  as  a  member  of  the  peridotite  group, 
and  is  not  classed  with  the  country  rocks. 

The  gneiss  of  this  region,   wherever   found  in    contact   with  the 


56  CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 

peridotites  near  the  surface  is  considerably  decomposed,  crumbling 
easily  into  a  loose  sand,  though  retaining  a  fresh  appearance  and 
the  original  structure  of  the  unchanged  rock  so  far  as  may  be  seen 
with  the  unaided  eye. 

In  the  description  of  the  secondary  products  found  in  connection 
with  the  alteration  of  dunite,  mention  was  made  of  the  enstatite 
casing  which  often  surrounds  the  jointed  masses  of  the  rock.  In 
most  cases,  it  is  quite  clear  that  these  casings  are  closely  connected 
with  the  chloritic  zones  that  bear  corundum.  They  are  composed 
of  enstatite,  often  fibrous  and  usually  altered  more  or  less  to  talc  : 
and  the  structure  is  radial,  or  parallel,  the  fibres  standing  normal 
to  the  outer  surface  of  the  dunite  block  enclosed.  In  all  cases 
observed,  the  enclosed  rock  is  more  or  less  altered,  and  frequently 
to  such  an  extent  that  only  a  soft  ochreous,  clay-like  mass  remains, 
though  the  casing  may  be  tough  and  apparently  fresh.  These 
casings  often  contain  more  or  less  chlorite,  and  especially  towards 
their  outer  portions;  furthermore,  they  are  never  developed  ex- 
cept in  places  where  chlorite  is  also  formed  along  the  borders  and 
more  prominent  joints  of  the  peridotites;  and,  vice  versa,  some 
slight  development,  at  least,  of  such  enstatite  always  lies  between 
the  chlorite  and  the  olivine  rocks. 

The  whole  zone,  consisting  of  chlorite,  vermicnlite,  talc,  and  the 
enstatite  border  is  frequently  sheared  until  all  original  structure 
is  replaced  by  a  high  development  of  schistosity. 

A  number  of  other  minerals  are  always  present  in  minor  pro- 
portions, varying  in  importance  in  the  different  localities.  Some 
variety  of  amphibole,  pyroxene,  spinel,  and  tourmaline  are  fre- 
quently observed;  staurolite,  diaspore,  and  anthophylliteare  occa- 
sionally seen  ;  and,  where  the  corundum  is  associated  with  feld- 
spar, margarite  and  zoisite  are  frequent  accompaniments.  Muscov- 
ite, margarite,  and  other  minerals  that  so  often  form  the  wrapping  of 
corundum  crystals,  appear  to  be  in  many  cases  undoubtedly  the 
results  of  alteration  of  that  mineral,  as  indicated  by  the  researches 
of  Dr.  F.  A.  Genth. 

The  green  and  yellow  micaceous  minerals,  known  respectively  as 
chlorite  and  vermiculite,  have  been  divided  into  several  more  or  less 


OOKUNDUM    IN    CHLORITE    SCAIST. 


57 


definite  species  based  on  chemical  analyses.  Lucasite,  kerrite, 
culsageeite,  jefferisite,  wilcoxite,  etc.,  are  some  of  the  names 
that  have  been  given  to  the  yellow  and  brownish  minerals  ;  but 
the  distinctions  are  almost  purely  chemical,  and  the  names  are  of 
no  practical  value  in  the  held  examinations;  and,  in  most  cases, 
their  use  would  tend  only  to  confusion.  These  are  all  grouped 
here  under  the  name  vermiculite.  Pennine,  clinochlor,  prochlor- 
ite,  cornndophilite,  etc.,  are  some  of  the  more  important  subdivi- 
sions of  the  chlorite  group  ;  but  the  same  condition  exists  here  as 
in  the  vermiculite  group,  so  far  as  field  distinctins  are  concerned, 
and  the  term  chlorite  is  used  for  all  green  colored  micaceous 
minerals  associated  with  corundum  and  the  olivine  rocks. * 

In  the  midst  of  these  Chlorite  zones,  corundum  is  sometimes 
found  in  veins  of  feldspar,  as  at  Buck  creek,  and  with  amphibole 
rocks  in  Iredell  county.  In  rare  cases  quartz  is  intergrown  with 
the  feldspar,  forming  a  true  pegmatite.  Such  a  vein,  without  cor- 
undum is  found  at  the  Hamlin  prospecting,  on  the  head-waters  of 
Ellijay  creek,  in  Macon  county. 

b.    CORUNDUM  IN  CHLORITE  SCHIST. 

An  occurrence  in  some  respects  similar  to  that  in  the  chloritic 
zones  about  peridotites,  is  found  in  the  long  belts  of  chlorite  schist 
that  traverse  the  country  ten  to  twelve  miles  southeast  of  Webster. 
Chloritic  rocks  here,  which  sometimes  attain  a  width  of  several 
hundred  feet  are  traceable  across  the  country  for  several 
miles.  Green,  scaly  chlorite  is  almost  the  only  constituent  of 
these  rocks,  though  sometimes  they  are  flecked  with  small  white 
grains  of  feldspar,  and  occasionly  amphibole  needles  are  seen. 
The  chlorite  is  in  small  scales,  never  very  coarse,  as  is  sometimes 
the  case  in  the  zones  about  peridotite,  and  often  they  are  so  min- 
ute as  to  impart  quite  a  compact  appearance  to  the  rock. 

In  one  of  these  belts,  on  Caney  Fork  of  Tuckaseegee  river,  cor- 
undum is  disseminated  through  the  chlorite  in  small  rounded 
masses,  ranging  from  an  inch  in   diameter  to   minute  grains.      In 


*A  careful  investigation  of  the  chemical  and  mineralogic  relations  of  corundum  and 
its  associated  minerals  is  now  being  pursued  by  Mr.  Joseph  H.  Pratt,  of  Yale  University 
and  the  most  of  these  minerals  are  here  referred  to  only  in  a  general  way. 


5S  CORUXDCM    AXD    BASIC    MAGNESIAS    BOCKS. 

these  cases,  the  chlorite  is  not  so  tough  and  compact  as  elsewhere, 
and  the  corundum  is  invariably  wrapped  in  a  coating  of  white 
mica,  usually  in  radiating  scales  perpendicular  to  the  outer  sur- 
face of  the  corundum.  The  mica  coating  is  exceedingly  thin  in 
some  cases,  but  it  is  so  variable  that  many  nodules  are  composed 
almost  entirely  of  it  with  only  a  small  grain  of  corundum  in  the 
centre.  The  secondary  nature  of  this  mica  and  its  derivation  from 
the  corundum  can  scarcely  be  doubted. 

C.    CORUNDUM  IX  AMPHIBOLITE. 

The  beautiful  grass-green  hornblende  rock,  which  forms  impor- 
tant dike-like  masses  at  various  peridotite  localities  iD  Clay  county, 
was  described  above  among  the  massive  rocks  associated  with  per- 
idotite (p.  28).  Besides  the  green  hornblende  and  the  an orth.it e 
which  constitute  the  principal  constituents  of  the  rock,  there  is 
always  present,  in  the  corundum-bearing  phase,  microscopic  grains 
of  picotite,  and  the  smaller  grains  of  corundum  are  usually  inter- 
grown  with  irregular  masses  of  this  mineral  and  enclose  many 
minute  particles  of  it. 

The  corundum  ranges  in  size  from  the  minute  microscopic 
grains  to  large  masses  of  several  inches  in  width,  and  is  usually 
laminated  or  possesses  a  parting  according  to  the  rhombohedron, 
which  breaks  it  into  small,  nearly  cubical  blocks.  It  ranges  in 
color,  too,  from  almost  white  to  deep  ruby-red.  most  of  it  being  of 
quite  a  decided  red  color.  Some  portions  of  the  rock  are  thickly 
studded  with  corundum,  and  boulders  of  this  kind  have  been 
gathered  from  the  surface  at  Buck  creek  and  hauled  on  wagons  to 
Corundum  Hill  to  be  crushed  for  separation.  It  has  furnished 
some  handsome  cabinet  specimems,  the  contrast  of  the  bright  red 
and  green  colors  producing  a  striking  effect ;  but  it  is  an  exceed- 
ingly tough  rock  and  is  not  likely  soon  to  become  a  commercial 
source  of  corundum. 

The  corundum  that  has  been  found  in  place  in  the  vicinity  of 
Statesville,  Iredell  county,  is  developed  in  the  joint-planes  and 
along  the  borders  of  coarse  hornblende  rocks,  much  in  the  same 
manner  as  that  with  dunite  at  Corundum  Hill  and  elsewhere  in 
the  more  westerly  counties.      These  hornblende  rocks  appear  in 


CORUNDUM    IN    AMPHIBOLITE. 


59 


the  gneisses  somewhat  as  the  peridotites,  so  far  as  may  be  judged 
from  the  meagre  outcroppings  available,  and  the  corundum  is 
found  with  fine  brown,  scaly  vermiculite,  which  is  developed  in 
zones  from  a  few  inches  to  three  or  four  feet  in  thickness,  along 
the  borders,  and  through  irregular  joints  in  the  hornblende  rock 
(See  figure  4).  In  one  or  two  instances,  feldspar  veins  five  or  six 
inches  thick,  sometimes  altered  to  kaolin,  were  observed  in  the 
midst  of  the  vermiculite  zones.  This  feldspar  often  bears  corundum 
also,  though  in  prospecting  most  of  it  was  found  with  the  vermi- 
culite. The  corundum  is  in  crystals  and  rounded  masses  of  crys- 
tals clustered  together;  sometimes  margarite  accompanies  it,  and 
large  masses  have  been  found  on  the  surface  in  this  region  made 
up  of  these  two  minerals. 


Fig.  4. 

Fig.  4.  Diagram  illustrating  the  mode  of  occurrence  of  corundum  in  amphibolite  at 
Hunter's,  seven  miles  west  of  Sfcaiezviile,  Iredtdl  councy.  a,  Feldspar  vein,  (not  always 
present)  sometimes  carrying  corundum;  b,  Fine  scaly  vermiculite  with  crystals  and 
lumps  of  corundum;  o,  Radiating  uorder  of  actinolite  enclosing  large  blocks  of  (d)  dark 
green  hornblende  rock. 


Still  another  point  of  similarity  to  the  occurrences  in  connection 
with  peridotite  is  found  in  the  radiating  borders  that  intervene 
between  the  corundum-bearing  vermiculite  z.ones  and  the  massive 
rock.  In  this  case,  the  radiating  border  is  composed  of  a  green 
horneblende  similar  to  actinolite,  instead  of  the  enstatite.  Sim- 
ilarly, the  rounded  blocks  thus  inclosed  are  often  almost  completely 
decomposed  ;   so   that   we  find,   on   breaking    through   this   radial 


60 


CORUNDUM  AND   BASIC  MAGNESIAN   ROCKS. 


casing,  only  a  mass  of  ochreons  clay  b(  aring  occasional  needles 
of  horneblende  and  scales  of  brown  vermiculite. 

d.    CORUNDUM  IN  DUNITE. 

Thus  far  I  have  observed  but  one  instance  of  this  association; 
and,  so  far  as  I  am  aware,  it  is  entirely  unique.  This  was  found 
at  the  Egypt  mine  on  the  western  slopes  of  the  Sampson  moun- 
tains, in  Yancey  county,  by  Mr.  U.  S.  Hayes,  who  was  prospect- 
ing at  the  time  of  my  visit.  I  am  indebted  to  him  for  two  of  the 
best  specimems  collected,  one  of  which  is  shown  in  figure  5.  It 
consists  of  a  hexagonal  crystal  of  corundum  completely  surrounded 
by  granular  dunite,  with  none  of  the  chloritic  minerals  which 
usally  intervene.  The  dunite  is  not  quite  fresh,  being  stained 
yellowish  brown  and  rather  friable.  A  little  muscovite  is  devel- 
oped along  the  basal  parting  planes  of  the  corundum,  as  is  often 
the  case  in  other  occurrences. 


Fig.  5. 

Fig.  5.    Corundum  crystal  in  altered  d  unite.    From  Egypt  (Hayes)  mine,  Yancey  countv. 
One-half  natural  size.    (Drawn  from  a  photograph.) 

With  one  possible  exception,  so  far  as  I  am  aware,  this  is  the 
first  instance  of  such  anomolous  mineral  association  yet  recorded. 
In  enumerating  the  minerals  of  the  Buck  creek  corundum  locality, 
in  1875,  the  late  Dr.  C.  D.  Smith  states  that  he  found  "chrysolite 
attached  as  an  enveloping  matter  to  considerable  masses  of  cor- 
undum ;"  *  but  as  neither  Dr.  Smith  nor  any  of  the  numerous 
writers  on  this  subject  during  the  succeeding  twenty  years  have 
made  any  further  mention   of  this  extraordinay  discovery,  it  may 

*Report  of  the  North  Carolina  Geological  Survey,  1875,  Appendix  page  95, 


CORUNDUM    IN    GNEISS. 


61 


be  fairly  assumed,  I  think,  that  this  passage  refers  only  to  the 
ordinary  occurrence  of  corundum  in  the  chlorite  zones  developed 
within  the  peridotite  and  along  its  borders. 

e.    CORUNDUM  IN  GNEISS. 

In  the  same  belt  of  crystalline  rocks  that  carries  the  peridotite, 
but  apparently,  in  no  way  connected  with  the  latter,  corundum  is 
found  in  a  number  of  localities  in  the  ordinary  gneiss  of  the  coun- 
try. Five  years  ago  Dr.  Genth  *  described,  as  a  new  mode  of 
occurrence  for  corundum,  that  discovered  in  the  mica  schist  region 
of  Patrick  county,  Virginia.  The  schists  are  sometimes  garnet- 
iferous  and  gn eissic,  and  the  corundum  is  associated  with  andalu- 
site,  cyanite,  chloritoid,  mica,  etc.  The  schists  were  intersected 
with  granite  dikes,  and  the  corundum  was  found  near  these  in 
crystals  and  rounded  masses  on  the  surface. 

In  the  North  Carolina  localities,  corundum  occurs  in  place  in 
the  gneiss  in  nodules  of  half  an  inch  in  diameter  and  smaller,  and 
wrapped  in  a  sheath  of  radiating  muscbvite,  similar  to  that  in  the 
chlorite  schist  described  above.  None  of  the  accompanying  min- 
erals described  by  Dr.  Genth  were  observed,  and  but  for  the  pre- 
sence of  these  nodules,  the  lock  seemed  to  be  in  every  way  normal 
gneiss.  The  nodules,  on  account  of  their  resistance  to  the  decom- 
posing forces  of  the  atmosphere,  always  stand  out  prominently  on 
the  weathered  surface;  and  they  are  often  present  in  such  propor- 
tion as  to  thickly  stud  these  surfaces  with  little  white  and  grayish 
knots. 

In  one  instance,  however,  the  corundum-bearing  gneiss  is  asso- 
ciated with  basic  magnesian  rocks,  though  such  has  not  yet  been 
shown  to  be  the  case  in  other  instances.  The  basic  rock  referred 
to  here  occurs  on  the  head  waters  of  Shooting  creek,  in  Clay  county, 
and  consist  largely  of  fine  grained  green  horneblende  and  hypers- 
thene — the  latter  somewhat  predominating.  The  sections  of  this 
rock  have  not  been  sufficiently  studied  to  determine  whether  the 
horneblende  is  primary  or  secondary,  but  the  preponderence  of  the 
hypersthene  would  give  ground  for  calliing  it  hypersthenite.  This 
rock  cuts  through  the  gneiss  in   two  dikes  about  ten   feet  thick 

*F.  A.  Genth,  Am.  Jour.  Science,  3,  xxxix,  1890,  pa^es  47,  48. 


62  CORUNDUM   AND    BASIC    MAGNESIAN    ROCKS. 

t 

and  about  500  or  600  feet  apart.  The  Corundum  is  found  in 
the  gneiss  between,  intimately  associated  with  a  small  pegmatite 
vein  and  a  band  of  very  black  mica. 

Just  beside  one  of  the  dikes  also,  corundum  was  found  in  a  zone 
of  line  scaly  brown  mica.  This  corundum  is  in  nodules  and,  like 
that  in  the  gneiss  betweeu  the  dikes,  has  two  systems  of  parting 
well  developed. 

In  other  localities,  no  such  relation  to  magnesian  rocks  has  been 
observed.  The  covering  of  soil  and  decomposed  rock  is,  however, 
very  deep  in  some  places,  and  quite  sufficient  throughout  most  of 
this  region  to  render  the  outcrops  rather  obscure. 

On  the  western  side  of  Chunky  Gal  mountain,  bands  of  brown 
mica,  bearing  lumps  of  granular  garnet,  and  both  carrying  more  or 
less  corundum,  are  found  in  the  gneiss.  So  far  as  determinable  at 
the  time  of  my  visit,  the  corundum  here  has  no  connection  with 
peridotite  or  similar  rocks. 

/.    CORUNDUM  IN  GRAVEL  DEPOSITS. 

It  is  well  known  that  the  gem  varieties  of  corundum  are  found 
chiefly  in  the  soil  and  gravel  beds  of  Burma,  Ceylon,  and  other 
regions  of  southern  Asia.  Along  with  these,  the  common  forms 
of  crystalized  corundum  are  also  found  ;  and,  in  some  of  the  local- 
ities, the  mineral  has  been  traced  to  its  origin  in  the  crystalline 
rocks. 

The  gravel  beds  represent  the  result  of  ages  of  concentration. 
While  the  rocks  have  been  slowly  decomposing  and  crumbling 
away  through  the  agencies  of  air  and  water,  the  stream  beds  fur- 
nished a  natural  system  of  sluices  in  which  the  heavy  and  more 
resistant  minerals,  including  corundum,  have  been  caught  and 
retained,  while  the  lighter  material  has  been  carried  out  to  the 
sea.  Hence,  although  the  corundum  gems  may  have  been  quite 
rare  in  the  original  rock,  they  are  found  in  these  gravel  deposits 
in  cotriparitive  abundance  ;  and  even  when  the  original  source  is 
found,  the  gravels  still  remain  the  principal  commercial  source. 

Most  of  the  corundum  localities  of  North  Carolina  have  beeu 
found  through  the  discovery  of  fragments  in  the  soil  or  in  beds  of 
streams;  and  it  is  a  favorite  method  with  prospectors  to  wash   the 


. 


distribution'  of  corundum.  63 

gravels  of  stream  beds  for  corundum,  much  in  the  same  manner  as 
search  is  made  for  gold.  Similarly,  corundum  crystals  have  been 
ploughed  up  in  bottom  lands,  and  further  investigation  has  revealed 
gravel  beds,  often  of  considerable  extent,  which  usually  bear  sev- 
eral varieties  of  corundum.  Search  up  the  stream  and  its  tribu- 
taries till  no  further  trace  is  found  and  then  up  the  adjoining 
hillsides,  has  in  many  instances  brought  to  light  the  source  of 
these  valley  deposits  ;  but,  in  a  number  of  cases,  such  search  has 
proven,  thus  far,  fruitless;  and  we  are  led  to  the  conclusion  that 
the  corundum  must  have  been  concentrated  from  rocks  in  which 
it  is  only  a  rare  constituent. 

Several  such  deposits,  in  Macon  and  Jackson  counties,  have  fur- 
nished ruby-colored  corundum  of  nearly  every  shade,  and  consider- 
able attention  has  been  devoted  to  the  search  for  gems.  Occasion- 
ally pieces  are  found  sufficiently  transparent  and  free  from  flaws 
to  be  cut  into  fair  gems,  though  most  of  it  is  too  much  clouded 
and  the  parting  too  highly  developed  to  be  of  any  value  except  as 
mineral  specimems.  The  principal  object  of  the  recent  work 
in  these  gravels  has  been  to  locate  the  original  source  of  the 
material  in  the  hope  that  the  finer  specimens  may  be  found  in 
sufficient  quantity  to  establish  gem  mining  on   a  profitable  basis. 

Small  grains  and  crystals  of  corundum  are  found  in  the  gold 
placers  of  Rutherford,  McDowell  and  Burke  counties, 'but  they 
are  not  considered  of  sufficient  importance  to  be  indicated  on  the 
map. 

(5.)    DISTRIBUTION  OF  CORUNDUM. 

As  indicated  above,  in  the  description  of  the  modes  of  occurence, 
the  home  of  corundum  is  in  thet  highly  crystalline  rocks,  and 
chiefly  in  the  region  of  gneisses.  This  is  true  of  all  occurrences 
that  attain  to  any  but  purely  scientific  interest. 

a.     IN  THE  APPAI.ACHAIN  BKI/T. 

In  describing  the  distribution  of  peridotites,  mention  has  already 
been  made  of  the  occurrence  of  corundum  in  Pennsylvania,  North 
and  South  Carolina,  Georgia  and  Alabama.  In  these  states,  the 
corundum  localities  are  found  along  the  peridotite  belt  .indicated 
on  the  general  map  (plate  II,  p.  32).      Other  localities  are  found  as 


16 


64  CORUNDUM    AND    BASIC    MAGNESIAS    ROCKS. 

indicated  above,  which  are  not  intimately  connected  with  these 
rocks  ;  but  thus  far  none  of  these,  except  the  emery  of  Chester, 
Massachusetts,  has  become  of  economic  importance. 

Corundum  in  Alabama. — The  Appalachain  crystalline  belt 
passes  under  the  Cretaceous  and  later  sedimentary  formations 
in  the  central  part  of  the  State  near  Montgomery.  Representatives 
of  the  peridotite  belt  have  been  found  in  the  vicinity  of  Dudley- 
ville,  in  Tallapoosa  county,  and  corundum  has  been  found  in  frag- 
ments on  the  surface  both  in  this  and  Coosa,  the  adjoining  county 
on  the  west.  A  little  search  would  doubtless  reveal  the  presence 
of  peridotite,  and  perhaps  also,'  corundum,  to  the  very  borders 
of  the  crystalline  rocks. 

Corundum  in  Georgia. — A  series  of  scattering  deposits  extends 
the  peridotite  belt  through  this  State  in  a  northeast  direction,  pass- 
ing in  a  general  way  up  the  valley  of  the  Chattahoochee  river  to 
the  western  extremities  of  North  and  South  Carolina.  Along  this 
line,  corundum  has  been  found  in  the  following  counties  :  Rabun, 
Towns,  Union,  Lumpkin,  Habersham,  Hall,  Cobb,  Paulding,  Doug- 
las, Carroll,  Heard,  Troup,  and  somewhat  off  the  line  to  the  east, 
in  Walton.  One  occurrence  is  reported  in  Forsyth  county  in  a 
region  of  mica  schist  and  garnetiiierous  horneblcnde  gneiss.  Con- 
siderable work  has  been  done  along  this  belt  in  the  nature  of 
prospecting,  and  for  a  number  of  years,  a  productive  mine  was 
operated  at  Pine  mountain,  in  Rabun  county.  * 

Corundum  in  South  Carolina. — Corundum  is  reported  from 
Laurens,  Anderson  and  Oconee  counties,  and  I  have  seen  speci- 
mens that  were  said  to  have  been  found  in  Pickens.  The  western 
portion  of  this  State  is  in  the  line  of  peridotites  as  indicated 
by  the  direction  of  the  belt  in  Georgia  and  North  Carolina,  and 
these  rocks  are  known  to  exist  along  the  border  in  the  north- 
western corner;  but  no  work  has  been  done  to  trace  out  their 
distribution  nor  to   develop   the  corundum  deposits,  if  such  exist. 

Corundum  in  North  Carolina. — As  remarked  above,  this  State 
presents  the  greastest  development  both  of  peridotite  and  corun- 
dum.    The  belt   here   attains   its  greatest   width,  and  the  largest 

*A  Preliminary  Report  on  the  Corundum  deposits  of  Georgia,  by  Francis  P.  King,  1894 
Bulletin  No.  2  of  the  Geological  Survey  of  Georgia. 


DISTRIBUTION    OF    CORUNDUM. 


65 


outcrops  of  chrysolitic  rocks  in  the  Atlantic  States  are  found  in 
the  southwestern  counties.  As  indicated  on  the  map,  (plate  I) 
corundum  occurs  in  Clay,  Macon,  Jackson,  Haywood,  Transylvania, 
Buncombe,  Madison,  Yancey  and  Mitchell  counties  along  the  belt 
of  basic  magnesian  rocks  ;  and  it  is  found  east  of  the  mountains  in 
the  counties  of  Cleveland,  Burke,  Gaston,  Alexander,  Iredell  and 
Guilford.  More  particular  mention  is  made  of  these  localities 
under  another  head  beyond. 

Corundum  in  Virginia. — Thus  far  I  have  been  able  to  find  cor- 
undum reported  from  only  two  localities  in  this  State.  The  first 
is  a  large  deep  blue  crystal  found  in  Louisa  county  by  Mr.  Louis 
Zimmer,  and  reported  by  Mr.  George  F.  Kunz.*  The  second  is 
that  described  by  Dr.  Genth  in  1890,  and  noted  above  in  describ- 
ing the  mode  of  occurrence  in  gneiss.  The  peridotite  belt  is  con- 
tinued through  the  State  by  a  great  number  of  talc  and  serpen- 
tine rocks,  but  no  corundum  has  been  reported  from  any  of  these 
localities. 

Maryland. — Although  the  peridotite  belt  is  well  represented  in 
this  State,  no  corundum  localities  are  known. 

Corundum  in  Pennsylvania. — The  serpentine  belt  that  comes 
diagonally  across  Maryland,  is  continued  through  the  counties  of 
Lancaster,  Chester,  Delaware,  Montgomery  and  Bucks.  Corun- 
dum is  found  associated  with  it  in  many  places,  especially  in 
Chester  and  Delaware  counties,  and,  a  few  years  ago,  wTas  mined 
to  a  certain  extent  in  the  former.  It  is  found  here  in  chloritic 
zones  about  the  serpentine,  but  in  larger  amounts  in  granular 
albite,  much  like  the  occurrence  in  feldspar  veins  at  Buck  creek,  in 
Clay  county,  North  Carolina. 

Zones  of  chloritic  minerals  along  the  borders  of  the  serpentine 
masses  and  in  the  larger  joints,  are  constantly  present  in  these  cor- 
undum localities,  and  chromite  is  found  in  the  mass  of  the  serpen- 
tine itself.  Considerable  prospecting  has  been  done  in  Pennsyl- 
vania, and  corundum  has  been  mined  in  one  or  two  places  but 
these  are  now  abandoned. 

Corundum  in  New   Jersey. — The   crystalline   belt    disappears 

*George  F.  Kunz,  Mineral  Recources  of  the  United  States,  1883-4,  page  736. 


66  CORUNDUM    AND    BASIC    MAGNESIAX    ROCKS. 

under  the  Jura-Trias  near  Trenton,  almost  immediately  on  crossing 
the  Pennsylvania  line.  Portions  of  it  outcrop  again  to  the  north- 
ward in  the  Highlands,  but  in  the  line  of  the  perhiotite  belt,  it 
does  not  reappear  till  we  find  it  on  the  opposite  side  of  the  State 
at  Hoboken,  where  serpentine  is  found,  but  no  corundum. 

Corundum  is  found,  however,  in  Sussex  county  along  the  bor- 
ders between  the  crystalline  limestones  and  the  gneiss. 

Corundum  in  New  York. — Corundum  is  also  found  with  the 
white  limestone  of  this  State  in  Orange  county.  Emery,  an 
intimate  mixture  of  granular  corundum  and  magnetite,  is  found 
east  of  Peekskill,  in  Weschester  county,  in  basic  magnesian  rocks. 
which  have  been  shown  to  be  eruptive  in  origin.*  This  Emery  is 
also  often  intimately  intergrown  with  chlorite  and  green  spinel, 
though  there  are  no  well  defined  chlorite  zones  such  as  are  devel- 
oped about  the^  peridotites  of  North  Carolina.  This  has  been 
mined  to  a  limited  extent,  though  the  product  is  said  to  have  been 
too  soft,  and  it  is  not  worked  now. 

Corundum  in  Connecticut. — Connecticut  has  thus  far  furnished 
only  surface  specimens  of  corundum,  nothing  of  commercial  impor- 
tance. Early  in  the  century,  a  mass  of  cyanite  was  found  at  Litch- 
field, "associated  with  talc,  sulphuret  of  iron,  and  corundum  .  .  . 
supposed  to  weigh  1500  pounds."!  Dana  also  reports  it  from 
Norwich.  Both  of  these  localities  are  in  regions  of  crystalline 
rocks. 

Corundum  in  Massachusetts. — About  thirty  years  ago,  the 
emery  vein  at  Chester  was  found  in  a  chlorite  schist  zone  lying 
between  a  talc  rock  on  the  east  and  a  horneblende  schist  on  the 
west.  The  vein  traverses  the  mountains  on  both  sides  of  Westfield 
river,  in  a  nearly  north  and  south  direction,  and  has  been  traced 
for  a  distance  of  about  four  miles.  A  typical  section  from  west  to 
east  would  be  about  as  follows  :  (a.)  Horneblende  schist,  black, 
coarse  crystalline,  often  feldspathic  and  banded,  gneissic;  (b.)  Chlo- 
ritic  schist,  bearing  lenticular  masses  of  emery  and  magnetite, 
sometimes  becoming  talcose,  and   often   bearing  radiating  tourma- 

*George  H,  Williams,  American  Journal  of  Science,  3.  1886.  XXXI:  pasres  26  41:  1887, 
XXXIII,  pa^es  135  144  and  J91-199;  1888,  XXXV,  pages  438-448 ;  1888,  XXXVI,  pages  254  26^. 

tEdward  Hitchcock,  American  Journal  of  Science,  1,  VI,  1823,  page  219. 


CORUNDUM    IN    NORTH    CAROLINA.  67 

line  clusters.  This  belt  is  usually  about  twenty  feet  wide,  (c.) 
Granular  quartz  in  a  vein  one  to  two  feet  wide  ;  sometimes  entirely 
disappearing,  (d.)  Talc  schist,  sometimes  chloritic  and  of  fine 
texture,  closely  resembling  serpentine;  fifteen  to  twenty  feet  wide. 
(e.)  Mica  schist  to  the  eastward. 

The  position  of  the  emery  in  the  chloritic  zone  (b.)  is  very 
variable,  and  it  often  lies  along  the  border  of  this  and  the  talcose 
rocks  (d).  The  emery  is  associated  with  diaspore  and  margarite, 
especially  about  the  edges  of  the  lenticular  masses.  Grains  of 
corundum  are  said  to  be  found  in  the  talc  rocks  sometimes.  This 
locality  is  still  worked,  and  is  the  only  productive  emery  mine  in 
the  United  States. 

A  few  years  after  the  discovery  of  emery  at  Chester,  corundum 
was  found  in  brown,  scaly  vermiculite  associated  with  asbestos 
and  other  amphibole  minerals  in  Pelham,  Massachusetts.  Pro- 
fessor B.  K.  Emerson  informs  me  in  a  private  letter  that  olivine 
rocks  are  also  found  here,  and  that  the  occurrence  is  very  similar 
to  the  corundum  localities  of  North  Carolina.  This  locality  has 
thus  far  proved  of  only  mineralogic  interest,  however. 

In  the  numerous  serpentine  localities  of  the  State,  no  corundum 
has  been  found. 

b.    CORUNDUM  IN  NORTH  CAROLINA. 

We  come  now  to  a  more  detailed  consideration  of  the  corundum 
localities  of  North  Carolina.  In  a  general  way,  these  are  all 
indicated  on  the  map  (plate  I),  except  those  of  Gaston  and  Guilford 
counties  ;  and  in  the  following  enumeration  of  localities  the  per- 
idotite  belt  will  be  considered  first — beginning  with  thf  southwest- 
erly corner  of  the  State — and  afterwards,  the  localities  east  of  the 
mountains. 

Corundum  in  Clay  County. — One  mile  south  of  Elf  postoffice, 
on  Shooting  creek,  and  five  miles  southeast  of  Hayesville,  perido- 
tite  occurs  within  about  a  mile  of  the  Georgia  line,  and  corundum 
is  found  associated  with  it  in  its  most  southerly  outcrops,  on  the 
property  of  W.  C.  Ledford.  It  occurs  here  in  "sand  veins"  in 
scaly   vermiculites  ;   and,  a  little  further  north,  it  occurs  in  feld- 


68  CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 

spar  veins  and  green  chlorite,  on  the  land  of  Samuel  Housed.  On 
the  same  place,  it  is  found  in  feldspar,  associated  with  zoisite, 
forming  considerable  masses;  also  in  rounded  nodules  with  rhom- 
bohedral  parting  (as  in  figures  1  and  3)  highly  developed,  and  cov- 
ered with  a  very  variable  coating  of  white  compact  mineral 
(margarite?)  which  has  undoubtedly  been  formed  from  the  alter- 
ation of  the  corundum.  Sometimes  only  small  grains  remain  in 
the  center  of  the  nodules,  while  the  coating  has  developed  to  great 
thickness. 

About  Elf,  are  found  outcrops  of  the  bright  green  amphibolite  : 
and  one  place  near  the  postoffice  by  the  roadside,  shows  beautiful 
red  corundum  plates  and  grains,  also  having  the  rhombohedral 
parting.  Sand  corundum  and  the  massive  variety  with  feldspar 
were  obtained  in  the  Behr  mine,  at  Elf.  Corundum  has  been  found 
on  the  surface  and  ploughed  up  in  fields  along  the  continuation  of 
this  peridotite  strip  up  Lick  Log  branch  almost  to  the  gap  between 
this  and  Tusquittah  creek. 

Except  a  few  loose  surface  fragments  near  Shooting  creek  post- 
office,  no  corundum  has  been  found  along  the  strip  of  dunite  and 
talc  that  passes  across  the  head- waters  of  Shooting  creek,  till  it 
reaches  the  slopes  of  Chunky  Gal  mountain  at  Newton  Penland's. 
From  this  point  it  has  been  found  all  the  way  up  the  mountain 
side  to  about  half  a  mile  east  of  the  summit,  where  it  narrows  to 
very  small  dimensions  and  finally  disappears.  The  occurrence  in 
feldspar  predominates  toward  the  point  of  this  outcrop,  and  this 
mode  is  found  along  with  the  sand  veins  and  crystal  corundum  on 
the  mountain  side  also.  A  decomposed  amphibolite,  bearing  cor- 
undum disseminated  through  the  mass  in  small  grains,  is  now  being 
extensively  prospected  near  Penland's,  and  encouraging  results 
are  reported. 

About  three  miles  from  Shooting  creek  postoffice,  on  Thumping 
creek,  at  Curtis  Ledford's,  is  the  corundum  locality  in  gneiss 
described  above  under  modes  of  occurrence  (p.  61).  Corundum  is 
found  here  in  rounded  nodules  in  the  gneiss  and  in  veins  of  black 
mica  ;  and  is  also  developed  in  vermiculite  beside  one  of  thehypers- 
thenite  dikes.  Some  work  has  been  done  here,  and  portions  of  the 
rocks  exposed  are  quite  thickly  studded  with  corundum. 


CORUNDUM  IN  NORTH  CAROLINA.  69 

At  the  head  of  Muskrat  fork  of  Shooting  creek,  and  about  half 
way  up  the  side  of  Chunky  Gal  mountain,  corundum  is  found  in 
garnet  rock  and  brown  scaly  mica.  This  is  also  described  above 
under  the  occurrence  of  corundum  in  gneiss  (p.  61).  This  was  being 
prospected  at  the  time  of  my  visit  in  the  summer  of  1894,  and 
the  work  is  said  to  have  been  resumed  again  this  year  (1895). 

The  only  remaing  deposit  in  Clay  county  is  that  with  the  great 
peridotite  mass  at  Buck  creek.  The  corundum  mined  here  is 
found  in  veins  of  coarse* feldspar  and  horneblende  near  the  eastern 
edge  of  the  peridotite.  In  fact,  only  a  few  feet  of  these  rocks  inter- 
vene between  the  corundum-bearing  vein  and  the  gneiss.  Some 
corundum  is  also  found  in  the  vermiculite  and  chlorite  that  are 
developed  through  joints  of  the  peridotite  on  the  hillside  west  of 
the  creek  ;  and  some  is  f  ;und  here  also  in  feldspar  associated  with 
zoisite  and  margarite.  Portions  of  the  bright  green  amphibolite 
at  this  locality  are  quite  full  of  corundum  ;  this  is  especially  true 
of  that  on  top  of  the  mountain  west  of  the  creek,  where  the  ground 
was  covered  with  fragments  of  this  rock  ;  but  many  of  these  have 
been  collected  and  hauled  to  Corundum  Hill  to  be  crushed  and 
separated.  The  locations  of  the  corundum  workings  at  this  place 
are  represented  on  the  map  (plate  III,  page  34). 

Corundum  in  Macon  County. — I  have  visited  and  located  on 
the  map  a  great  number  of  peridotite  and  soapstone  outcrops  in 
the  valley  of  the  Little  Tennessee  river  above  Franklin  ;  but,  so 
far  as  I  was  able  to  learn,  corundum  has  been  found  at  only 
one  of  those  places.  A  number  of  them  show  considerable 
development  of  chlorite,  and  a  little  careful  search  in  such  places 
might  be  well  rapaid.  The  locality  referred  to  is  at  the  head  of 
Hickory  Knoll  creek,  at  an  elevation  of  about  4000  feet,  on  the 
western  slope  of  Fish  Hawk  mountain.  A  number  of  small  dunite 
outcrops  are  found  here,  most  of  the  blocks  exposed  near  the 
surface  having  a  well  developed  radial  enstatite  casing.  Some 
corundum  has  been  found  in  small  encased  nodules. 

Six  miles  southeast  of  this,  and  just  south  of  mount  Scaly,  cor- 
undum is  found  in  small  crystals  and  grains  with  outcrops  of 
soapstone  and  a  fibrous,  asbestos-like  mineral.     Radiating  casings 


70  CORUNDUM    AND    BASIC    MAGNESIAN    BOCKS. 

* 

of  talc  here  enclosing  an  ochreous  earthy  material  doubtless  repre- 
sent the  peridotite,  which  does  not  appear  on  the  surface. 

The  next  corundum  region  encountered  lies  seven  miles  east  of 
Franklin,  just  north  of  the  Cullasaja  river,  and  included  between 
its  tributaries,  Ellijay  and  Walnut  creeks.  On  this,  one  of  the 
most  prominent  western  spurs  of  the  Cowee  mountains,  are  found 
more  promising  corundum  localities  than  in  any  other  region  of 
equal  area  within  the  State,  or  indeed,  in  the  whole  Appalachian 
crystalline  belt.  At  the  southern  point  of  this  spur  is  Corundum 
Hill,  the  most  widely  known  mine,  and  the  one  that  has  furnished 
by  far  the  greater  part  of  American  corundum  since  the  beginning 
of  the  industry.  A  map  (plate  TV,)  and  description  of  this  place 
are  given  under  the  head  of  the  distribution  of  peridotitite  (p.  36), 
and  a  sketch  of  its  history  will  be  found  beyond. 

It  is  entirely  unnecessary  to  add  anything  further  here  about 
the  occurrence  of  corundum  at  this  place.  In  this  region,  having 
a  total  area  of  less  than  twenty  square  miles,  there  are  at  least  fif- 
teen outcrops  of  peridotite;  and  corundum  in  greater  or  less  quan- 
tity has  been  found  associated  with  nearly  all  of  them.  Consider- 
able prospecting  has  been  and  is  now  being  done,  and  a  great  deal 
of  capital  has  been  invested  there  within  the  past  three  years. 

Corundum  has  been  found  and  some  prospecting  done  in  the 
gneiss  on  the  summit  of  Turkey  knob,  on  the  Macon-Jackson  county 
line,  and  fine  specimems  of  red  corundum  are  found  in  the  gravels 
of  Cowee  creek.  Well  formed  crystals  are  also  found  at  Xona 
postoffice,  seven  miles  west  of  Franklin,  in  the  soil  of  gneiss. 

Corundum  in  Jackson  County. — Loose  fragments  and  crystals 
of  corundum  have  been  found  at  Addie,  on  the  ring  of  peridotite 
that  lies  northeast  of  Webster,  (see  (plate  Y,  p.  38.)  but  pros- 
pecting has  not  yet  located  any  important  deposit  in  place.  Good 
specmens  of  red  corundum  are  found  in  gravel  beds  on  the  head- 
waters of  Cullowbee  creek. 

On  Caney  Fork,  two  miles  above  its  mouth,  corundum  is  found 
in  the  chlorite  schist  in  the  manner  described  on  page  57,  on 
Mrs.  Chastain's  place  and  at  Marion  Long's.  By  digging  a  very 
shallow  pit,  a  width  of  eight  feet  of  this  rock  was  exposed  which 
was  thickly  studded  with  nodules  of  corundum.      On  Johns  creek, 


CORUNDUM    IN    NORTH    CAROLINA. 


71 


half  a  mile  above  its  junction  with  Caney  Fork,  a  chlorite  schist 
outcrop  occurs  with  a  width  of  about  a  thousand  feet.  Corundum 
is  said  to  be  found  in  fragments  over  the  surface,  but  no  prospect- 
ing has  been  done. 

At  the  mouth  of  Chastains  creek,  five  miles  up  Caney  Fork, 
corundum  is  found  in  the  gneiss  near  the  residence  of  W.  W. 
Biown.  It  is  in  nodules  one-half  to  one  inch  in  diameter,  and 
surrounded  by  a  thin,  compact  casing.  Two  miles  up  Chastains 
creek,  corundum  is  found  in  the  same  manner  in  the  gneiss,  near 
a  belt  of  chlorite  schist.  At  many  points  along  Caney  Fork,  cor- 
undum is  reported  to  be  found  in  the  fields  and  elsewhere  over  the 
surface.  So  far  as  I  was  able  to  learn,  corundum  has  been  found 
in  only  one  place  on  West  Fork,  and  that  in  association  with  a 
chlorite  rock  on  Shoal  Creek  mountain,  four  miles  north  of  Glen- 
ville. 

South  of  Sapphire,  corundum  is  found  with  peridotite  on  Snake 
ridge  at  several  places;  and  on  the  lands  of  Dr.  C.  Grimshawe, 
near  Montvale  postoifice,  in  both  Jackson  and  Transylvania  coun- 
ties. 

At  the  Sapphire  mines,  corundum  is  found  in  similar  associa- 
tions in  a  great  number  of  places  on  both  sides  of  Horespasture 
river,  and  on  the  spars  of  Great  Hogback  mountain.  Several  of 
these  localities  have  been  mined  by  the  Sapphire  Yalley  Company, 
and  have  yielded  considerable  quantities  of  corundum  for  the 
market.  In  a  number  of  the  outcrops,  enstatite  rock  predominates, 
though  more  or  less  peridotite  may  be  seen  in  nearly  all  of  them. 
The  mutual  relations  of  these  two  rocks  at  some  of  the  localities, 
as  at  the  "Sapphire1'  mine,  is  such  as  to  strongly  point  to  the 
derivntion  of  the  enstatite  from  the  olivine. 

Besides  a  number  of  places  that  have  been  prospected,  the  fol- 
lowing localities  have  been  mined,  to  a  greater  or  less  extent,  and 
constitute  jointly  the  Sapphire  mines.  I  am  indebted  to  Mr. 
Charles  N.  Jenks,  the  superintendent,  for  the  characterization  of 
the  product  of  the  different  workings. 

The  "Burnt  Rock"  mine  is  a  mile  and  a  half  northeast  of  Great 
Hogback   mountain,    and   produces   nodular,    massive   corundum. 


72 


CORUNDUM     AND    BASIC    MAGNESIAN    ROCKS. 


Some  of  the  blocks  taken    out    weighed  as  much  as   twenty-five 
pounds. 

The  "Brockton"  mine  is  about  a  mile  south  of  the  Burnt  Rock, 
and  its  product  is  a  dull  gray  crystal  corundum,  which  is  easilv 
separated  from  the  vermiculite  ganffue. 

The  "Rattlesnake"  mine  is  a  mile  and  ahalf  southwest  of  Great 
Hogback  mountain  and  about  the  same  distance  northeast  of 
Sapphire.  Crystal  and  sand  corundum  are  found  here  in  chlo 
rite  and  vermiculite  about  the  borders  of  the  enstatite  rock. 

The  "Sapphire"  mine  is  somewhat  less  than  a  mile  northeast 
of  Sapphire,  and  near  where  the  Brevard  road  crosses  Big  Hog- 
back creek.  The  product  of  this  place  is  crystals  and  masses  of 
white  and  gray  corundum  specked  and  mottled  with  blue. 

The  "Socrates"  mine  is  half  a  mile  south  of  Sapphire,  on  the 
north  end  of  Bear  Pen  mountain.  The  corundum  here  is  neither 
in  crystals  nor  masses,  but  occurs  in  "shotty"  nodules  in  the  chlo- 
rite veins  through  enstatite  rock.  This  furnishes  the  most  perfect 
grain  produced  by  these  mines,  and  is  well  adapted  to  the  manu- 
facture of  either  cement  or  vitreous  wheels. 

The  "Bad  Creek"  mine  is  on  the  west  side  of  Bear  Pen  moun- 
tain and  about  half  a  mile  from  the  Socrates  mine.  The  corun- 
dum here  is  massive,  and  occurs  with  chlorite,  margarite,  garnet, 
biotite,  feldspar,  and  a  number  of  rarer  minerals,  forming  a  hard, 
tough  vein.  Mr.  Jenks  informs  me  that  corundum  constitutes 
about  35  per  cent,  of  the  whole  mass,  but  that  it  is  very  difficult 
to  separate  it  thoroughly  from  the  gangue. 

The  "  Whitewater"  mine  is  about  six  miles  southwest  of  Sap- 
phire, on  Whitewater  river.  The  corundum  occurs  here  in  col- 
ored crystals,  possessing  some  gem  characteristics,  and  producing 
a  good  solid  grain. 

All  of  the  lacalities  enumerated  lie  near  the  Jackson-Transyl- 
vania county  line,  and  the  first  three  are  situated  in  the  latter 
county.  A  number  of  intermediate  outcrops  have  been  prospected 
a  little,  and  still  others  yet  remain  untouched. 

Corundum  in  Transylvania  County. — The  Sapphire  mines 
"Burnt  Rock,"  "Brockton,''  and  "Rattlesnake, "  described  above, 
are  located  in  this  county,  on  the  spurs  of  Great  Hogback  mountain. 


CORUNDUM  IN  NORTH  CAROLINA.  73 

Corundum    is  said  also  to  be   found   with    enstatite  rocks    in  the 
same  vicinity,  on  the  headwaters  of  the  Toxaway  river. 

On  the  West  fork  of  the  French  Broad  river,  I  saw  corundum 
with  similar  rocks  on  the  hill  just  west  of  the  mouth  of  Owens 
creek.  A  number  of  shallow  pits  had  been  dug  in  prospecting, 
and  large  masses  of  margarite  had  been  thrown  out,  bearing  cor- 
undum and  black  tourmaline  Asbestiform  minerals  are  also 
found  at  the  same  locality. 

A  large  number  of  similar  outcrops  are  found  to  the  eastward 
and  northeastward,  and  corundum  is  said  to  occur  with  some  of 
these  on  the  North  Fork  of  the  French  Broad  river;  but  I  was 
unable  to  verify  these  reports,  owing  to  the  profound  air  of  secrecy 
maintained  by  the  alleged  discoverers. 

Near  the  mouth  of  Owens  creek,  east  of  the  corundum  locality 
described  above,  a  number  of  large  boulders  of  disthene  (cyanite) 
have  been  found  on  the  surface,  bearing  grains  and  crystals  of 
deep  sapphire-blue  corundum.  The  rocks  at  this  locality  are 
ordinary  gneiss. 

Corundum  in  Haywood  County. — On  Pigeon  river,  at  Retreat 
postofhce,  six  miles  southeast  of  Waynesville,  corundum  is  found 
with  cyanite  and  margarite  in  crystals  scattered  through  the  soil. 
The  rocks  are  garnetiferous  mica  schist  and  gneisses,  and  no 
deposit  has  yet  been  found  in  place. 

Three  miles  northeast  of  Canton,  corundum  has  been  found  on 
the  surface  with  an  outcrop  of  dunite,  but  no  workable  deposit  has 
been  discovered.  A  mile  north  of  this,  at  the  "Presley  mine," 
corundum  occurs  in  pegmatite  veins  through  dark  green  horn- 
blende rock.  The  corundum  occurs  both  in  the  mica  and  the 
feldspar  of  the  pegmatite,  and  is  sometimes  wrapped  in  margarite. 
It  often  has  the  appearance  of  having  altered  into  these  minerals. 

Just  south  of  Newfound  gap,  red  corundum  is  found  on  the 
surface  about  a  small  lenticular  mass  of  dunite.  It  is  also  reported 
from  a  soapstone  outcrop  near  the  gap  between  Cabes  and 
Crabtree  creeks. 

Corundum  in  Buncombe  County. — Just  south  of  the  Carter  mine, 
near  the  Madison  county  line,  corundum  is  found  about  Democrat 


71 


CORUNDUM    AND    BASIC    MAGNESIAN    EOCKS. 


with  the  long  strip  of  peridotite  which  crosses  Big  Ivy  river  at 
this  place.  The  Carter  mine  is  in  Madison,  and  very  little  pros- 
pecting has  been  done  in  Buncombe. 

At  Swannanoa  gap,  on  the  eastern  border  of  the  county,  cor- 
undum is  occasionally  found  in  masses  of  cyanite. 

Corundum  in  Madison  County. — The  Carter  mine  is  very  near 
the  Bumcombe  county  line,  in  the  eastern  end  of  the  county,  and 
is  situated  on  Holcombe  branch,  a  tributary  of  Little  Ivy  river. 
It  is  at  the  north  end  of  the  strip  of  dunite  which  is  continous 
from  Morgan  Hill,  in  Buncombe  county.  The  corundum  here 
occurs  in  a  vein  of  chlorite  and  vermiculite  which  is  developed 
at  right  angles  to  the  lamination  of  the  peridotite.  It  is  in 
masses  of  white,  pink,  and  blue  colors,  and  is  intergrown 
with  greenish  black,  massive  spinel   and  feldspar. 

Recently,  Mr.  John  A.  Carter,  of  Democrat,  has  found  a  crys- 
tal of  mottled  bine  and  white  corundum  weighing -16  pounds.  It 
is  hexagonal  in  form,  though  rough  and  irregularly  broken,  and  has 
the  rhombohedral  parting  well  developed.  It  was  found  loose 
above  the  Carter  mine  in  a  small  stream  very  near  its  head,  but 
search  failed  to  discover  its  source. 


Fig.  7.  Hexagonal  crystal  of  corundum  showing  rhombohedral  twinning.  A,  oblique 
view;  B,  end  view;  one-fourth  natural  size;  weight  17  pounds.  From  an  amphibolite  out- 
crop half  a  mile  north  of  the  mouth  of  Ivy  river,  Madison  county.  (Specimen  in  posses- 
sion of  Mr.  G.  C.  Haynie,  Marshall,  N.  C    Figure  drawn  from  photographs.) 


The  first  corundum  found  in  North  Carolina  was  picked  up 
from  the  surface  three  miles  below  Marshall,  just  above  the  mouth 
of  Little  Pine  creek.     A  belt  of  soapstone  and  peridotite  crosses 


CORUNDUM    IN    NORTH    CAROLINA. 


75 


the  river  near  this  point,  but  the  locality  has  never  furnished  a 
second  specimen,  so  far  as  I  was  able  to  learn. 

Three  miles  above  Marshall  and  half  a  mile  north  of  the  mouth 
of  Big  Ivy  river,  corundum  is  found  in  large  gray  crystals  on 
the  surface  of  a  large  hornblende  outcrop.  One  crystal  from 
this  place  (figure  7),  which  weighs  17  pounds,  and  exhibits  fine 
rhombohedrol  twinning,  is  in  possession  of  Mr.  G.  C.  Haynie,  of 
Marshall,  the  owner  of  the  property. 

Corundum  in  Yancey  County. — The  principal  corundum  local- 
ity of  this  county  is  that  known  as  the  "Egypt  (or  Hayes)  mine," 
ten  miles  west  of  Burnsville,  on  the  western  slopes  of  Sampson 
mountain.  Corundum  occurs  in  green  chlorite  along  the  bor- 
ders of  dunite  and  enstatite  rock,  the  latter  predominating.  It 
is  generally  in  distinct  crystals,  though  granular  massess  are 
also  found.  The  prevailing  colors  are  white  and  banded  or  mot- 
tled blue  and  white.  The  corundum  imbedded  in  dunite  (figure 
5),  and  the  crystal  shown  in  figure   3  are  from  this  locality. 

Eight  miles  southeast  of  Burnsville,  on  Celos  Ridge,  near 
South  Toe  river,  corundum  is  found  in  crystals  of  two  or  three 
inches  in  diameter  in  the  decomposed  gneiss  adjoining  an  out- 
crop of  enstatite  rock. 

Corundum  in  Mitchell  County. — Three-fourths  of  a  mile  west 
of  Bakersville,  corundum  crystals  are  found  in  the  gneiss  at  Wil- 
liam Bowman's.  I  also  saw  fragments  of  corundum  on  the  sur- 
face and  in  the  dump  a  mile  and  a  half  up  White  Oak  creek  from 
Bakersville,  where  work  had  been  done  for  asbestos.  The  rock 
is  a  massive  enstatite  with  fine  radiating  borders  similar  to  those 
found  about  dunite  in  many  places. 

Since  my  visit  to  this  region,  Mr.  D.  A.  Bowman,  a  local  min- 
eralogist, of  Bakersville,  writes  me  that  "one  mile  due  east  from 
Bakersville,  a  massive  blue  corrundum  occurs,  with  now  and  then 
a  hair-brown  piece."  He  further  states  that  in  the  sumer  of  1888 
he  obtained  about  600  lbs.  at  this  place,  one  piece  of  which 
weighed  23£  pounds.  "Some  small  blue  crystals  found  at  this 
place  would  cut  very  nice  gems  were  it  not  for  cleavages." 

~No  corundum  has  yet  been  found  in  North  Carolina  north  of 
Bakersville. 


76 


CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 


Corundum  in  Iredell  and  Alexander  Counties. — The  country 
rock  in  these  counties  is  ordinary  gneiss,  and  surface  specimens 
of  corundum  are  found  scattered  over  a  large  number  of  local- 
ities, especially  in  Iredell.  Grayish  masses  are  found  several 
inches  in  diameter,  and  the  smaller  ones  frequently  have  crystal 
form.  All  are  more  or  less  altered,  and  most  of  the  specimens 
have  a  sheath  of  compact  damourite  or  margarite,  (figure  8)  which 
is  sometimes  developed  to  such  an  extent  that  only  a  trace  of 
the  original  corundum  remains  in  the  interior. 


Fig.  8.  A  tapering  crystal  of  black  corundum  enclosed  in  a  sheath  of  compact  mar- 
garite. One-half  natural  size.  From  Belts  bridge,  Iredell  county.  (Drawn  from  a  pho- 
tograph.) 

In  the  alluvial  deposits  first  worked  by  the  Acme  company  at 
Statesville,  blue  and  pink  corundum  was  found  in  clays  and 
sands,  either  in  small  loose  pieces  or  in  masses  with  cyanite.  On 
passing  through  the  clays  and  gravels,  a  massive  hornblende 
rock  was  encountered,  and  a  little  search  discovered  a  vein  of 
feldspar  bearing  corundum  and  separated  by  vermiculite  from 
the  hornblende  rock  through  which  it  passed.  In  its  widest 
place,  this  feldspar-corundum  vein  had  a  thickness  of  two  and  a 
half  feet,   and  was  very  rich  in  corundum. 

The  only  other  locality  where  corundum  has  been  found  m 
place  in  this  region  is  eight  miles  northwest  of  Statesville,  and 
just  north  of  the  Charlotte  and  Taylorsville  railroad,  on  the  Hun- 
ter place.  Here  no  such  alluvial  deposits  were  encountered,  and 
the  amphibolite  is  of  much  finer  texture  than  that  at  Statesville. 
But  otherwise,  the  occurence  is  very  much  the  same.  The  cor- 
undum is  almost  coal-black  and  is  associated  with  feldspar  and 
vermiculite  in  the  joint  system  of  the  rocks,  much  in  the  same 
manner  as  that  found  in  some  of  the  dunite  localities  of  the  moun- 
tain region.      The  mode  of  occurrence  is  described  and  illustrated 


CORUNDUM     IN    NORTH    CAROLINA. 


77 


(figure  6)  on  page  93.  Near  this  place,  large  masses  of  corun- 
dum with  margarite  are  found  on  the  surface.  The  soil  and 
decomposed  rock  are  so  deep  over  this  region  that  very  little  can 
be  determined  about  the  form  or  extent  of  these  amphibolites. 
Only  occasionally  does  a  stream  or  a  wash  in  the  hill  side  offer 
an  exposure  of  rock  that  may  be  readily  recognized. 

Corundum  in  Burke  and  Cleveland  Counties. — lam  indebted 
to  Mr.  H.  B.  C.  Nitze  for  the  following  notes  in  regard  to  the 
•occurrence  of  corundum  along  the  borders  of  Burke  and  Cleve- 
land counties,  near  the  corner  of  Catawba.  The  rocks  of  the 
region  are  highly  garnetiferous,  gneissic,  mica  schist.  Grayish 
blue,  tapering  corundum  crystals  are  found  on  the  surface  along 
the  ridge  leading  northwest  of  Carpenters  knob.  On  the  waters  of 
the  South  Fork  of  the  Catawba,  in  Burke  county,  corundum  of  a 
similar  nature  is  found  in  "pockets"  containing  from  one  to  two 
hundred  pounds.  Monazite  is  found  in  the  placers  of  the  streams. 
Dr.  Genth  mentions  "crystals  of  corundum  surrounded  by  fibro- 
lite"  from  this  locality.* 

Corundum  in  Gaston  County. — Corundum  was  discovered  in 
this  county  at  Crowders,  Chubbs,  and  Kings  mountains  by  Dr. 
C.  L.  Hunter,  about  forty  years  ago.  It  was  found  in  masses  and 
six-sided  crystals  "in  place — associated  with  mica  and  quartz 
aggregate."  Margarite  was  found  with  it ;  and,  in  places,  by  the 
gradual  introduction  of  iron  oxids,  a  transition  to  granular  emery 
was  observed.  ~No  large  quantities  have  been  found  here,  and 
thus  far,  the  discovery  has  proved   of  only  mineralogic  interest. 

Corundum  in  Guilford  County. — In  the  titaniferous  iron  ore 
belt  that  traverses  the  northwest  corner  of  Guilford  county,  Dr. 
Genth  found  true  emery  at  the  McChristian  (or  McCuiston)  place, 
seven  miles  north  of  Friendship.  One  variety  was  reddish,  gran- 
ular, and  had  "much  the  appearance  of  agranular  reddish  brown 
garnet,  for  which  it  has  been  mistaken,  until  the  analysis  proved 
it  to  be  not  a  silicate,  mixed  with  granular  magnetite,  but  corun- 
dum."    Another,  found  in  the  same  locality  was  grayish  in  color; 

^Bulletin  74,  U.  S.  Geological  Survey,  1891.  The  Minerals  of  North  Carolina,  page  30. 


78  CORUNDUM  AXD  BASIC  MAGXESIAX   ROCKS. 

and  "the  minute  crystals  of  eorudum  have  a  yellowish  or  brownish 
white  color,  and  show  in  many  places  cleavage  fractures, 
which  give  it  the  appearance  of  a  feldspathic  mineral."^ 

The  following  analyses  of  these  varities  are  given  in  the  same 
place. 

Analyses  of  J^mery  from  the  McChristian  place,  7  miles  north  of  Friend- 
ship, Quilford  county. 

REDDISH  BROWN.  &RAY. 

Silica 1.39  0*98 

Titanic  acid 0.78  2.42 

Magnetic  iron  oxid r.. 42.77  46.29 

Oxid  of  Manganese  and  Cobalt 1.00  1.27 

Chromium  oxid 0.80  trace 

Alumina  52.24  44.86 

Magnesia 0.68  3.27 

Lime 0.84  0.91 

100.00  100.00 

Corundum  in  other  localities. — Tn  the  report  of  the  North 
Carolina  Geological  Survey  for  1S75,  large  hexagonal  crystals  of 
corundum  are  reported  from  Forsyth  county  (page  299),  and  a 
reddish  variety  from  Polk  (Appendix  page  65).  Small  particles 
are  also  said  to  occur  in  cyanite  in  Wilkes  county  :  and  Dr. 
Genth  says  that  "rarely  small  remnants  of  corundum  are  found 
in  the  pyrophyllite  slates  of  Chatham  county."  He  also  men- 
tions the  locality  of  Y  alley  river  in  Cherokee  county  for  corun- 
dum, and  says  that  emery  is  found  near  Salem,  Forsyth  county.  + 
I  have  not  yet  had  an  opportunity  to  verify  these  reports,  but 
hope  to  do  so  before  publishing  a  final  report  on  this  subject. 

(6.)   METHODS   OF  PROSPECTIXG    FOR    CORUXDUM. 

The  early  discoveries  of  corundum  in  North  Carolina  were  not 
the  result  of  any  systematic  search  ;  in  fact,  corundum,  as  it  is 
now  known  in  this  State  and  Georgia,   was  not  then   a  commer- 

*Report  of  the  Geological  Survey  of  North  Carolina,  I.,  1815,  pages  245,  246. 
tBulletin  74,  U.  S.  Geological  Survey,  1891,  pages  29-31,  96. 


METHODS    OF    PROSPECTING    FOR    CORUNDUM.  79 

cial  mineral,  and  nothing  was  known  of  its  occurrence  with 
peridotite.  Accidental  finding  of  surface  fragments  led  to  the 
discovery  of  extensive  deposits  ;  and  the  subsequent  working  of 
these  and  other  localities  has  given  to  mineralogy  and  mining 
a  great  fund  of  information  on  this  subject  that  is  to  a  large 
extent  entirely  new.  As  usual  in  the  case  of  things  new,  many 
mistakes  were  made  in  early  prospecting  and  attempts  at 
mining.  Mistakes  are  made  yet,  and  they  will  doubtless  con- 
tinue for  some  time  to  come,  but  many  of  the  earlier  errors  need 
not  be  repeated  if  due  regard  is  had  to  the  store  of  information 
that  has  been  accummulated  by  more  than  twenty  years  of  expe- 
rience. 

Those  who  would  search  for  corundum  had  best  see,  first  of  all, 
an  actual  corundum  mine  or  a  place  where  prospecting  has  been 
done  and  corundum  found;  and  note  carefully  the  conditions.  In 
the  southwestern  portion  of  the  State  this  may  easily  be  done  with- 
out great  inconvenience.  If  the  preceding  pages  have  been  read, 
or  even  a  small  portion  of  them,  it  will  already  be  understood 
that  conditions  are  rarely  duplicated  exactly,  even  in  localities 
very  near  together.  Certain  types  of  rocks  and  minerals,  how- 
ever, may  be  observed  in  the  greater  number  of  them  ;  and  these 
may  be  profitably  used  as  guides  in  searching  for  new  localities. 
Of  course  the  prospector  must  be  able  to  recognize  corundum 
itself  in  all  of  its  common  forms. 

Loose  fragments  of  corundum  in  the  soil  or  stream  beds  are, 
of  course,  the  surest  "signs"  of  corundum  deposits,  though  not 
always  the  most  easily  traced  to  their  origin.  The  extreme 
resistance  of  the  mineral  to  the  ordinary  process  is  of  abrasion  and 
decomposition  render  it  almost  indestructible  when  exposed  on  the 
surface.  Hence,  it  may  be  transported  tor  great  distances  down 
the  mountain  slopes  and  streams  without  showing  any  apprecia- 
ble alteration  and  but  little  wear.  When  associated  with  frag- 
ments of  peridotite,  chlorite,  or  talc,  the  corundum  is  a  much 
more  valuable  guide.  In  such  cases,  it  has  probably  been  trans- 
ported only  a  short  distance,  and  the  search  for  the  source 
becomes  far  less  difficult.      Where    no    corundum    is   found    with 


80  CORUNDUM    AND    BASIC    MAGNESIAS'    ROCKS. 

the  rock  fragments  or  minerals  indicated,  and  none  is  found  by 
panning  the  soil  or  sand,  as  in  the  ordinary  search  for  gold,  there 
is  little  encouragement  to  seek  further. 

The  "indications"  are  followed  up  the  grade  by  which  they 
would  most  naturally  have  reached  their  present  position.  If  in 
a  stream  bed,  the  search  is  made  up  the  stream  or  its  tributaries 
till  fragments  are  no  longer  found,  and  then  up  the  adjoining 
hillsides  till  the  parent  mass  of  peridotite  is  reached.  The  bor- 
ders of  this  rock  are  first  examined.  If  the  border  is  not  readily 
found  by  inspection,  ditches  are  cut  through  the  soil  and  decom- 
posed surface  materials  at  right  angles  to  the  strike  of  the 
country  rock.  The  chlorite  and  vermiculite  along  the  contact 
between  the  gneiss  and  peridotite  should  then  be  examined  for 
corundum.  A  ditch,  passing  completely  through  the  soil, 
should  follow  this  contact  zone;  and,  at  intervals,  shallow  pits 
or  cuts  should  be  sunk  to  disclose  the  nature  of  the  deposit. 
Where  no  encouraging  development  is  found  about  the  borders, 
it  may  be  worth  while  to  cut  ditches  across  the  peridotite  mass 
for  the  examination  of  the  joint  zones;  but  these  are  usually  less 
developed  than  those  about  the  borders. 

Margarite  is  found  abundantly  with  corundum  in  some  places, 
but  in  the  majority  of  the  North  Carolina  localities,  this  is  not 
true,  and  its  discovery  usually  follows,  rather  than  precedes, 
that  of  the  corundum.  The  emery  mine  at  Chester,  Massachu- 
setts, however,  was  discovered  by  the  finding  of  this  mineral, 
and,  when  found,  it  is  to  be  regarded  as  a  good  "indication." 

Obviously,  the  points  given  above  apply  chiefly  to  corundum 
associated  with  peridotite.  It  is  found,  however,  in  a  number  of 
other  associations  in  the  State,  and  several  of  those  in  amphibo- 
lite  and  gneiss  give  promise  of  becoming  of  commercial  import- 
ance. For  these  occurrences,  there  seems  to  be  no  important 
index,  except  to  find  the  corundum  itself.  When  it  is  developed 
in  considerable  quantity,  there  should  be  no  difficulty  in  finding 
it  in  the  soil  and  in  the  gravels  of  the  adjacent  streams. 

In  some  cases,  where  chlorite  and  vermiculite  are  found 
abundantly  on  the  surface,  it  may  be  advisable  to  trace  them  to 
their  origin,  even  though  corundum  may  not   be   found   floating 


MINING    AND    CLEANING    METHODS.  81 

in  the  soil  with  them.  Corundum  itself,  however,  is  the  only 
sure  indication  of  new  deposits,  and  other  guides,  though  often  of 
valuable  assistance,  should  be  regarded  as  pointing  only  to  proba- 
bilities. 

An  ordinary  wash-pan,  or  even  a  shovel,  will  serve  very  well 
in  examining  the  gravels  or  soil;  and  any  one  may  readily  deter- 
mine for  himself  whether  corundum  occurs  in  a  given  locality. 
By  a  little  practice,  all  the  heavy  minerals  in  the  soil  or  gravel 
may  be  shaken  to  the  bottom  of  the  pan  and  the  lighter  mate- 
rials washed  off  over  the  edge.  The  heavy  minerals  will  be  found 
usually  to  contain  grains  of  magnetite,  garnets,  dark  hornblende, 
and  corundum,  if  any  is  present. 

Finally,  however  good  the  indications,  even  from  the  presence 
of  corundum  itself,  no  extravagant  anticipation  or  large  invest- 
ments are  justifiable  till  the  deposit  has  been  thoroughly 
explored  by  intelligent  prospecting.  Had  this  truth  been  borne 
in  mind,  trite  as  it  may  seem,  much  disappointment  and  financial 
loss  would  have  been  avoided  and  the  mining  reputation  of  the 
State  saved  many  serious  blows. 

(7.)   MINING    AND  CLEANING    METHODS. 

Twenty-five  years  ago,  the  corundum  fields  under  considera- 
tion were  entirely  new  to  the  mining  world.  Corundum  itself, 
as  a  commercial  article  was  scarcely  known  except  in  the  forms 
of  emery  and  the  gems;  as  an  associate  of  peridotite,  it  was  not 
even  known  to  mineralogy.  There  were  no  precedents  in  min- 
ing, and  every  step  was  evolved  by  the  slow  and  expensive  pro- 
cess of  experiment.  Undue  excitement  had  been  created  by  the 
finding  of  a  few  gems,  and  the  idea  that  corundum  might  be 
profitably  mined  as  an  ordinary  abrasive  had  scarcely  been  con- 
cieved. 

Under  these  conditions,  the  first  undertaking  (at  Corundum 
Hill)  was  naturally  a  failure.  A  hydraulic  method  with  short 
sluice  systems  was  adopted  for  working  the  corundum-bearing 
soil  and  gravels,  and  some  of  the  chlorite  zones  were  opened. 
Only  the  larger  crystals  and  promising  gem  materials  were  saved. 


82  CORUNDUM     AND    BASIC    MAGNESIAN    ROCKS. 

With  the  exception  of  the  gems,  the  product  was  sold  for  cabinet 
specimens  and  for  the  manufacture  of  dental  appliances  ;  but  the 
work  was  soon  found  unprofitable.  The  concentrated  gem-bear- 
ing gravels  were  exhausted,  and  the  mine  abandoned. 

Two  great  mistakes  were  made  in  this  early  work  ;  first,  too 
much  importance  was  attached  to  gem  mining  ;  and,  second,  the 
smaller  fragments,  or  "sand-corundum,"  which  afterward  became 
the  most  important  product,  were  allowed  to  waste.  Prospect- 
ing, and  some  small  attempts  to  mine  in  other  localities  during 
the  next  few  years,  soon  demonstrated  the  scarcity  of  true  gems. 
When  Dr.  H.  S.  Lucas  reopened  the  work  at  Corundum  Hill,  it 
was  purely  for  the  purpose  of  mining  corundum  as  an  abrasive. 
and  methods  were  adopted  for  saving  the  whole  product  of  the 
mine.  On  this  basis,  the  work  has  been  successfully  continued 
to  the  present  time,  not  even  closing  down  entirely  during  the 
panic  of  1893  and  1894. 

Mining  Methods. — Naturally,  the  methods  of  work  adopted  in 
the  few  places  that  have  really  been  mined,  as  distinguished  from 
prospecting,  have  varied  greatly,  according  to  location,  character 
of  material,  and  other  variable  conditions.  The  area  under  con- 
sideration is  located  entirely  in  the  mountainous  and  hilly  districts 
of  the  western  part  of  the  State,  and  the  outcrops  are  usually  on 
high  ground,  with  abundant  natural  drainage.  These  conditions 
and  the  nature  of  the  border  zones  of  chlorite  and  vermiculite. 
which  are  the  principal  deposits  worked,  have  led  to  the  adoption, 
in  the  majority  of  cases,  of  open  cuts  and  drifts. 

So  long  as  the  work  is  confined  to  the  comparatively  superficial 
portions  of  the  deposit,  the  open  cut  is  the  most  advantageous. 
But,  with  increase  in  depth,  the  jointed  peridotite,  with  its  great 
development  of  slippery  magnesian  minerals  along  the  cracks,  is 
exceedingly  liable  to  fall  in.  Such  cuts  at  Corundum  Hill,  at  a 
depth  of  twenty  to  thirty  feet,  have  loosened  great  masses,  and 
have  sometimes  produced  cracks  in  the  surface  at  a  considerable 
distance  from  the  working.  These  are  a  continual  menace  to  the 
miners;  and,  in  a  few  cases,  they  have  slipped  into  the  cuts, 
though  without  more  serious  result  than  to  stop  the  work. 


MINING    AND    CLEANING    METHODS.  83 

The  same  trouble,  though  to  a  less  degree,  is  sometimes  exper- 
ienced in  drifts,  and  it  is  very  difficult  to  timber  the  workings  in 
such  a  manner  as  to  be  perfectly  safe.  Much  of  this  trouble, 
however,  is  really  due  to  unsystematic  work  and  employment  of 
unskilled  men.  After  the  work  in  open  cuts  had  been  rendered 
impracticable  at  Corundum  Hill,  the  mining  was  continued  by 
drifts.  In  one  place,  several  of  these  have  been  driven,  one 
above  another,  in  the  same  vein. 

In  a  few  localities,  small  shafts  have  been  sunk,  but  generally, 
this  is  done  only  where  the  configuration  of  the  surface  is  not 
favorable  to  cuts  and  drifts.  The  expense  of  hoisting  and  pump- 
ing incurred  in  shafts  is  probably  the  chief  objection  to  them. 

The  material  handled,  in  the  great  majority  of  cases,  is  loose, 
scaly  chlorite  and  '  vermiculite  with  corundum  disseminated 
through  it,  and  is  easily  removed  with  a  pick  and  shovel.  In 
solid  feldspar  veins,  however,  as  in  some  of  the  Sapphire  mines, 
and  at  Laurel  Creek  (Ga.)  and  Buck  Creek,  blasting  has  to  be 
resorted  to,  and  afterward  the  material  crushed  for  cleaning. 
One  of  the  drifts  at  Corundum  Hill  is  now  being  cut  through 
the  gneiss  wall  adjoining  the  peridotite.  It  is  very  hard  and 
thickly  impregnated  with  corundum,  and  must,  of  course,  be 
removed  by  blasting.  In  removing  the  material  from  the  mines, 
hand  cars  and  wheelbarrows  are  employed.  It  is  then,  according 
to  its  nature,  dumped  into  wagons  or  sluice-troughs  to  be  carried 
to  the  mill  for  cleaning. 

Methods  of  Cleaning. — The  prime  object  of  all  methods  of 
cleaning  corundum  is,  of  course,  the  removal  of  all  impurities  as 
completely  as  possible  ;  for  any  other  mineral  that  is  ever  found 
in  association  with  corundum,  though  it  may  be  very  hard  itself, 
is  always  softer,  and  if  left  with  it  in  considerable  quantity,  will 
appreciably  reduce  its  abrasive  power.  But  the  mere  removal 
of  impurities  is  not  the  only  point  to  be  considered  in  devising 
methods  of  cleaning.  This  must  be  done  with  the  least  possible 
injury  to  the  cutting  power  of  the  corundum  grains.  The  sharp 
edges  attained  by  crushing  must  not  be  ground  off,  and  no  large 
percentage  of  it  should  be  lost  by  reducing  it  to  "  flour." 


84  CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 

Owing  to  the  high  sjDecific  gravity  of  corundum,  it  can  be 
effectually  separated  from  most  of  its  associated  minerals  by 
washing  methods  in  many  ways  similar  to  those  adopted  in 
placer  mining  for  gold.  Where  the  corundum  occurs  loose  in 
chlorite  and  vermiculite  scales,  little  other  treatment  is  nec- 
cessary  ;  but,  when  it  is  enclosed  in  a  tough  gange  of  feldspar, 
margarite,  and  other  minerals,  or  is  a  constituent  of  a  solid  rock, 
as  in  the  gneiss  and  some  of  the  amphibolite  occurrences,  the 
minerals  must  be  thoroughly  broken  apart  before  separation. 
For  the  accomplishment  of  this  purpose,  the  abrasive  power  of 
the  corundum  itself  is  used,  by  scouring  the  crushed  material 
together,  so  that  the  particles  cut  the  softer  minerals  from  each 
other.  All  cleaning  methods,  then,  involve  the  three  processes, 
crushing,  scouring,  and  washing.  The  means  by  which  these 
processes  are  applied  may  be  best  understood  by  descriptions  of 
concrete  cases. 

Methods  of  cleaning  Corundum  at  Sajyjjhire. — I  am  indebted  to 
Mr.  Charles  ~N.  Jenks  for  the  following  outline  of  methods 
adopted  by  him  at  the  Sapphire  mines. 

With  crystal  corundum,  which  is  found  in  loose,  scaly  vermi- 
culite, only  the  simplest  treatment  is  necessary.  It  is  placed  in 
a  box  through  which  flows  a  strong  current  of  water,  and  stirred 
vigorously  with  hoes.  The  scaly  minerals  float  off  with  the  cur- 
rent, leaving  the  corundum  about  95  per  cent,  pure  ;  and  this 
requires  only  crushing  and  sifting  into  sizes  to  prepare  it  for  the 
market. 

But  with  every  other  variety  of  corundum,  the  separation  of 
impurities  is  more  difficult  and  the  methods  of  treatment  corres- 
pondingly more  complicated.  The  material  is  first  broken  into 
coarse  grains  by  passing  through  crushers  and  rolls.  In  this 
process,  much  of  the  adhering  impurities  is  broken  loose  ;  and 
this  may  be  partly  removed  by  the  gravity  process  described 
above  ;  that  is,  by  stirring  in  a  strong  current  of  water.  It  is 
then  passed  through  a  machine,  in  which  a  coarse  worm,  like  a 
screw-conveyer,  is  carried  on  a  revolving  shaft.  In  this  the 
adhering  minerals  are  cut  away  by  the  grinding  of  the  corundum 
grains    upon    each    other;   after    this  it    is   again    subjected    to 


MINING    AND    CLEANING    METHODS.  85 

the  gravity  treatment  in  a  strong  current  of  warter.  The  last 
process,  and  one  by  which  the  corundum  is  brought  to  a  high 
degree  of  purity,  is  in  a  machine  called  the  "muller",  or  "chaser". 
In  this  machine,  two  heavy  wooden  rollers  move  around  the  cir- 
cumference of  a  shallow  tub.  The  partially  cleaned  corundum 
is  thrown  into  this  tub,  and  is  stirred  constantly  by  iron 
teeth  that  move  in  front  of  the  rollers.  Being  thus  alternately 
stirred  up  by  the  teeth  and  pressed  down  by  the  rollers,  a  scour- 
ing motion  is  continually  kept  up  between  the  grains,  and  the 
impurities  are  gradually  cut  away.  In  this  action,  the  impuri- 
ties are  reduced  to  the  form  of  a  fine  powder,  and  are  carried 
away  by  a  small  current  of  water  which  continually  flows  through 
the  tub.  This  process  is  continued  from  three  to  five  hours,  accor- 
ding to  the  difficulty  of  cleaning  and  the  degree  of  purity  required. 

Methods  of  cleaning  Corundum  at  Corundum  Hill. — Two  classes 
of  material  are  produced  by  this  mine;  namely,  the  sand  corun- 
dum (and  crystals)  contained  in  the  vermiculite  and  chlorite  devel- 
oped along  the  borders  and  in  the  joints  of  the  peridotite  ;  and 
the  contact  gneiss  impregnated  with  corundum.  Each  of  these 
requires  its  special  mode  of  treatment. 

Until  recently,  the  sand  corundum  veins  were  the  only  depos- 
its worked  at  this  mine.  All  of  the  material  of  this  class  is  sent 
from  the  mine  to  the  mill,  a  distance  of  a  mile  and  a  half,  in  a 
small  trough  carrying  a  swift  current  of  water.  In  this  course, 
there  are  seA7eral  vertical  drops  of  five  to  ten  feet  to  facilitate  in 
breaking  loose  the  scaly  minerals  adhering  to  and  enveloping  the 
corundum.  At  the  mill,  all  material  that  will  not  pass  through 
a  screen  of  II  mashes  to  the  inch  is  crushed  between  rolls  and 
passed,  with  the  originally  fine  material,  to  the  gravity  boxes,  or 
sluices,  where  it  is  vigorously  stired  in  a  strong  current  of  water. 
It  is  then  treated  in   mullers,   as  in  the  process  described  above. 

The  gneissic  material  comes  from  the  minein  hard,  tough  blocks, 
sometimes  quite  large,  and  is  hauled  to  the  mill  on  wagons.  A 
very  primitive  method  is  adopted  for  breaking  the  large  blocks  into 
sizes  suitable  for  the  crushers.  A  fire  is  built  over  them  till  they 
are  heated  through,  and  then  they  are  suddenly  cooled  by  throw- 
ing on  water.      Fortunately,   only    a  small   part   of  the   product 


A 


86  CORUNDUM     AND    BASIC    MAGNESIAN    ROCKS. 

requires  this  treatment.  It  is  then  passed  through  crushers  and 
coarse  and  fine  rolls  till  it  will  all  pass  through  meshes  II  to  an 
inch.  It  is  then  subjected  to  a  scouring  action  in  the  auger-like 
machine  described  above,  and  passed  on  to  the  gravity  boxes. 
The  final  cleaning,  as  in  the  other  case,  is  given  by  the  mullein. 

The  method  of  drying  in  use  at  Corundum  Hill  is  also  worthy 
of  notice.  When  the  material  is  removed  from  the  mullers,  it  is 
allowed  to  lie  over  night  in  a  heap  on  an  inclined  floor.  This 
material,  still  wet,  is  carried  up  in  an  elevator  and  dropped  verti- 
cally through  a  distance  of  about  twenty  feet  down  the  stack  of 
a  furnace.  At  the  bottom  of  this,  it  strikes  an  inclined  plane 
and  slides  down  this  for  a  few  feet  through  the  flames  of  a  wood 
fire.  By  this  time  it  is  thoroughly  dry,  and  is  passed  into  a  cham- 
ber beneath,  whence  it  is  removed  with  shovels  and  subjected  to 
a  final  sifting.  All  material  not  fine  enough  to  pass  through  a 
screen  with  14  meshes  to  an  inch  is  again  passed  through  the 
rolls,  and  the  entire  cleaning  process  is  repeated. 

The  corundum  thus  cleaned  is  shipped  to  the  company's  mills 
at  Chester,  Massachusetts,  where  it  is  further  crushed  and  sorted 
into  sizes  for  the  market.  The  coarser  numbers  are  also  passed 
through  magnetic  separators  for  the  removal  of  the  magiuetite. 


7.   HISTORICAL  SKETCH  OF  CORUNDUM  MINING  IN    AMERICA. 

The  following  chronological  outline  of  the  principal  discov- 
eries and  the  developement  of  corundum  mining  in  the  eastern 
United  States  has  been  compiled  from  the  sources  enumerated  in 
the  bibliography  at  the  end.  In  the  main,  these  sources  are  con- 
sidered reliable,  and  it  is  believed  that  the  outline  here  presented 
indicates  with  tolerable  accuracy,  not  only  the  origin  of  the  cor- 
undum mining  industry,  but  also  the  growth  of  our  knowledge 
of  corundum  in  many  of  its  most  important  mineralogic  and  geo- 
logic relations. 

Besides  the  enumerations  of  discoveries,  I  have   o-iven  short 


DISCOVERIES    AND    EARLY    DEVELOPMENTS.  87 

sketches  of  all  the  corundum  mines,  properly  so  called,  in  North 
Carolina. 

(1.)    DISCOVERIES   AND   EARLY   DEVELOPMENTS. 

So  for  as  I  have  found  in  the  literature  on  the  subject,  corun- 
dum was  not  known  in  America  before  1819.  In  that  year,  Mr. 
John  Dickson,  a  teacher,  of  Columbia,  South  Carolina,  sent  Prof. 
Silliman  a  lot  of  minerals  which  he  had  collected  on  a  tour  through 
the  Carolinas.  Among  these  was  a  regular,  six-sided  crystal  of 
blue  corundum  three-fourths  of  an  inch  long  and  one  inch  in  diam- 
eter, with  parting  and  striae  developed  similar  to  the  East  Indian 
corundum.  It  was  sent  without  label,  and  in  reply  to  an  inquiry 
as  to  its  locality,  Mr.  Dickson  writes:  "I  think  it  was  Laurens 
district;  at  all  events,   it  was  picked  up  by  my  own  hands,  if  not 

in  situ,  in  a  place    which  it  could  have  reached  only  by  one 

of  the  usual  and  natural  accidents  which  displace  minerals  of  all 
kinds I  am  sure  it  is  American  and  Carolinian."  l 

In  1822,  both  Edward  Hitchcock  and  Parker  Cleaveland  des- 
cribed the  mass  of  cyanite  found  at  Litchfield,  "associated  with 

talc    sulfuret  of  iron,    and    corundum supposed   to   weigh 

1500  pounds."  The  corundum  was  massive  and  in  six-sided 
prisms,  of  a  dark  grayish  blue  color,  and  imbedded  in  the  cyanite. 
Both  of  these  authors  attribute  their  information  to  Mr.  John  P. 
Brace.  2 

In  April,  1827,  at  a  meeting  of  the  Lyceum  of  Natural  History, 

New  York,  "Major  Delafield exhibited  crystals  of  Sapphire 

from  Newton,  Sussex  county,  New  Jersey."  3  In  1832,  Dr.  Fow- 
ler described  this  locality,  pointing  out  the  geologic  and  miner- 
alogic  relations  of  the  corundum.  It  is  found  along  the  border 
of  crystalline  limestone. 4 

According  to  Mr.  W.  W.  Jefferis  (as  quoted  by  Mr.  Joseph 
Willcox)  John  and  Joel  Bailey  claim  to  have  discovered  corun- 
dum in  the  serpentine  region  of  Chester  county,  Pennsylvania, 
about  1822  to  1825.     Dr.   Thomas   Seal  collected  specimens   at 

1Am,  Jour.  Sci.,  1,  III.,  1821,  4,229,  230. 

2Am.  Jour.  Sci.,  1,  VI.,  1823,  219;  Cleveland's  "Mineralogy  and  Geology,'1  Boston,  1822. 

3  Am.  Jour,  Sci.,  1,  XIII.,  1828,  380. 

4Am.  Jour.  Sci.,  1,  XXL,  1832,  319,  320. 


88  CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 

Unionville  about  1832,  and  Mr.  Jefferis  himself  saw  large  lumps 
in  the  fields  there  in  1837  or  1838. l  A  ton  of  surface  fragments  and 
boulders  was  collected  about  1839  and  shipped  to  Liverpool.  But 
the  search  for  the  source  of  this  material  was  unsuccessful  till  1873, 
when  a  large  lenticular  mass  was  found  in  place.  This  consisted 
chiefly  of  corundum  and  margarite  and  carried  some  fine  speci- 
mens of  diaspore.2 

In  a  report  on  the  Mineralogy  of  New  York,  in  1842, Lewis  C. 
Beck  mentions  the  occurrence  of  corundum  in  the  white  lime- 
stone near  Amity,  in  Orange  county. 

The  first  discovery  in  North  Carolina  was  a  large  detached 
block  of  dark  blue,  laminated  corundum,  found  three  miles  below 
Marshall,  in  Madison  county,  in  the  spring  of  1847.  Gen.  T.  C. 
Clingman,  after  considerable  search,  found  another  piece  in  the 
same  vicinity  in  1848 — about  a  year  before  the  first  discovery 
of  emery  in  place  in  Asia  Minor  by  Dr.  J.   L.  Smith.3 

In  1852,  Mr.  W.  P.  Blake  described  corundum  from  the  new 
locality  at  Yernon,  Sussex  county,  New  Jersey.4  In  the  spring 
of  the  same  year,  Dr.  C.  L.  Hunter  discovered  corundum  and 
emery  in  place  in  Gaston  county,  North  Carolina.5 

In  1864,  the  occurence  of  emery  at  Chester,  Massachusetts, 
was  predicted  by  Dr.  C.  T.  Jackson  from  his  discovery  of  mar- 
garite there — a  mineral  which  Dr.  J.  L.  Smith  had  just  found 
characteristic  of  the  emery  deposits  of  Asia  Minor.  On  Septem- 
ber 6th  of  the  same  year,  Dr.  H.  S.  Lucas  discovered  the  emery 
in  what  had  before  been  considered  only  deposits  of  magnetic 
iron  ore.6  Two  years  later,  distinct  crystals  of  corundum  were 
found  in  the  same  deposits.7  This  discovery  of  emery  soon  led 
to  the  establishment  of  active  mining,  the  first  of  its  kind  in 
America.  This  mine  is  still  worked,  though  it  has  not  been 
operated  continuously  from  the  beginning. 

>  /fin   1870,  Mr.    Hiram    Crisp    found   the    first    corundum    that 
ie/jfy£jl?W$$-  ^jjfentionto  the  present  mining  regions  of  North  Caro- 


2d  G-eol.  Sur.  Perm.,  C4, 1883,  348-351. 

1  Owl.  Sur.  Penn.,  13,  1875,  31-33. 

ull.  74,  U.S.  Geol.  Sur.,  1891,  293-1. 
♦Am.  JoiH-.  8cl.,  2,  -XIII.,  1852, 116. 
5 Am.  Jour.  Sci.,  2,  XV.,""1§§J  3*6. 

°The  exact  date  was  furnished  me  by  Dr.  Lucas  in  a  private  letter. 
'Am.  Jour.  Sci.,  2,  XXXIX.,  1865,  87-90;  XLIL,  1866,  421. 


NORTH    CAROLINA    CORUNDUM    MINES.  89 

lina.  This  was  found  at  what  is  now  the  Corundum  Hill  Mine — 
Mr.  Crisp  living  there  at  the*  time.  A  specimen  was  sent  to 
Professor  Kerr,  then  State  Geologist,  for  indentification,  and 
considerable  interest  was  aroused  on  the  discovery  that  it  was 
true  corundum.  In  the  same  year,  Mr.  J.  H.  Adams  found 
corundum  in  very  similar  relations  at  Pelham,  Massachusetts.* 

In  1870-71,  considerable  activity  was  displayed  in  the  search 
for  corundum  in  the  dunite  regions  of  the  southwestern  counties 
of  North  Carolina  ;  and  new  localities  were  soon  brought  to 
light  in  Macon,  Jackson,  Buncombe,  and  Yancey  counties.  In 
1871,  Dr.  Genth  also  discovered  the  emery  of  Guilford  county. f 
About  this  time,  Mr.  Crisp  and  Dr.  C.  D.  Smith  began  active 
work  on  the  Corundum  Hill  property,  and  removed  about  a 
thousand  pounds,  part  of  which  was  sold  to  collectors  for  cabi- 
net specimens.  Some  of  the  masses  weighed  as  much  as  forty 
pounds. 

In  the  fall  of  1871,  the  property  was  bought  by  Col.  C.  W. 
Jenks,  of  St.  Louis,  Missouri,  and  Mr.  E.  B.  Ward,  of  Detroit, 
Michigan  ;  and  mining  was  soon  begun  under  the  superinten- 
dence of  Col.  Jenks. 

In  reply  to  my  inquiry  about  the  discovery  of  corundum  in 
Iredell  county,  Mr.  J.  A.  D.  Stephenson,  of  Statesville,  writes 
me  as  follows  :  "The  first  corundum  found  in  Iredell  county 
was  found  by  myself  near  where  the  Collins  (Acme)  mine  is  now 
located,  either  late  in  1871  or  eariy  in  1875.  It  was  a  mass 
weighing  probably  two  pounds.  I  also  found  a  lot  of  pink  frag- 
ments near  by."  It  was  soon  discovered  in  loose  masses  and 
crystals  in  many  parts  of  the  county,  and  small  amounts  have 
been  found  in  Alexander,  the  adjoining  county  to  the  west. 

(2)    NORTH    CAROLINA    CORUNDUM    MINES. 

Mining  proper,  as  distinguished  from  prospecting,  has  thus  far 
been  restricted  to  a  few  localities  in  the  counties  of  Clay,  Macon, 
Jackson,  Madison,  and  Iredell.  Extensive  prospecting,  however, 
has  been  done  at  a  number  of  places  which  have  come  to  be  known 

*Am.  Jour.  Science,  2,  XLIX,,  1870,  271,  272. 
tRept.  Geol.  Sur.  of  N.  C,  L,  1875,  246. 


90  CORUNDUM    AND    BASIC    MAGNESIAN    ROCKS. 

locally  as  "  mines  ;  "  and  more  or  less  work  has  been  done  at 
nearly  all  the  localities  where  corundum  is  known  to  occur  in 
the  State.  Most  of  this  has  been  done  in  the  most  primitive  and 
unsystematic  manner.  Little  pits -are  dug  here  and  there,  no 
deeper  than  a  man  may  conveniently  throw  the  dirt  from 
with  a  shovel ;  and  trenches  are  dug,  apparently  at  random,  in 
every  direction  over  the  surface  about  the  peridotite  outcrops. 
At  few  of  the  corundum  localities  enumerated,  has  the  work  been 
sufficient  or  of  such  a  nature  as  would  reveal  the  extent  and 
value  of  the  deposit. 

Much  has  been  learned,  however,  by  the  experience  of  a  quar- 
ter century  ;  and  the  prospecting  of  recent  date  has  been  more 
intelligently  directed  and  the  results  correspondingly  more  satis- 
factory. To  find  that  a  place  has  been  prospected  and  aban- 
doned, however,  is  still  not  to  be  regarded  as  conclusive  evidence 
that  it  is  worthless  ;  and  I  have  no  doubt  that  the  work  now 
under  way,  and  that  of  the  future  will,  in  many  cases,  prove 
the  correctness  of  this  statement. 

Short  historical  sketches  of  the  following  mines  are  given 
below  : 

a.  The  Behr  mine,  Clay  county. 

b.  The  Buck  creek  (Cullakanee)  mine,  Clay  county. 

c.  The  Corundum  Hill  (Cullasaja)  mine,  Macon   county. 

d.  The  Sapphire  (Hogback)  mines,  Jackson  county, 

e.  The  Carter  mine,  Madison   county. 

f.  The  Acme  mine,  Statesville,  Iredell  county. 

In  the  preparation  of  these  sketches,  I  have  had  to  rely  partly 
on  such  information  as  could  be  gathered  piecemeal  here  and 
there  through  the  country  ;  but  chiefly,  and  especially  in  regard 
to  the  more  prominent  mines,  I  am  indebted  to  the  kindness  of 
superintendents  and  mine-owners  for  most  of  the  facts  presented 
here.  I  would  mention  especially  Dr.  H.  S.  Lucas,  who  first 
placed  corundum  mining  on  a  successful  basis,  and  who  has  been 
identified  with  the  industry  for  twenty  years  ;  and  Mr.  Charles 
~N.  Jenks,  superintendent  of  the  Sapphire  mines,  who  was  asso- 
ciated with  his  father,  Col.  C.  "W.  Jenks,  in  the  first  work  of  the 
kind  undertaken  on  a  commercial   scale.      Valuable  information 


NORTH    CAROLINA    CORUNDUM    MINES.  91 

has  also  been  furnished  by  Mr.  A.  M.  Stoner,  of  Franklin  ;  and, 
in  regard  to  recent  developments  and  prospecting,  I  am  much 
indebted  to  Mr.  L.  S.  Ropes,  of  Franklin,  and  Dr.  C.  Grimshawe, 
of  Montvale.  Mr.  J.  A.  D.  Stephenson,  of  Statesville,  Mr.  John 
A.  Carter,  of  Democrat,  and  Mr.  IT.  S.  Hayes,  of  Bald  Creek, 
have  furnished  important  data  in  regard  to  the  operations  in 
their  respective  localities. 

a.    THE  BEHR  MINE,  CEAY  COUNTY. 

This  mine  is  located  five  miles  east  of  Haysville,  at  Elf  post- 
office,  on  Shooting  creek.  It  was  opened  in  1880  by  Dr.  H.  S. 
Lucas.  It  was  afterward  bought  by  Herman  Behr  &  Company, 
of  New  York,  and  was  operated  till  1890.  A  steam  cleaning 
plant  was  erected  at  the  mine,  and  considerable  work  was  done. 
Much  of  this  was  doubtless  of  the  nature  of  prospecting,  but  I 
am  informed  that  several  car  loads  of  cleaned  corundum  were 
shipped.  The  location  of  the  mine  in  a  low  place  by  a  branch 
necessitated  the  constant  use  of  pumps  for  drainage.  The  near- 
est railroad  is  about  twenty-five  miles  distant. 

b.  THE   BUCK   CREEK    (CUUUAK  AJSTEE)    MINE,    CI,  AY   COUNTY.  „ 

In  the  report  of  the  North  Carolina  Geological  Survey  for 
1875,  Dr.  C.  D.  Smith  states  that  he  was  the  first  to  find  corun- 
dum at  Buck  creek.  Large  loose  blocks  with  feldspar  and  black 
horneblende  were  found  on  the  surface.  The  first  prospecting 
was  done  by  Maj.  Bryson  about  1875  ;  and  two  years  later  Mr. 
Frank  Meminger  worked  for  about  six  months  and  removed 
about  thirty  tons  of  corundum. 

For  a  period  of  ten  years  no  further  operations  were  under- 
taken ;  then  work  was  resumed  by  Mr.  Ernst  and  continued  for 
nine  months,  chiefly  in  the  nature  of  prospecting.  During 
another  period  of  four  years,  the  mine  was  idle  ;  then  operations 
on  a  liberal  scale  were  begun  by  Mr.  Gregory  Hart,  and  con- 
tinued for  a  year  and  a  half,  during  which  time  a  shaft  was  sunk 
on  the  feldspar  vein  and  several  open  cuts  made  on  the  chlorite 
zones  about  the  eastern  border  of  the  peridotite.  Considerable 
quantities   of  corundum  were  taken   out   during  this   time,   but 


92  CORUNDUM    AND    BASIC    MAGNESIAS    BOCKS. 

nothing  was  shipped.  Most  of  the  product,  however,  was  in 
large  massive  blocks  with  feldspar  and  black  horneblende,  and 
there  was  no  economic  method  of  crushing  and  cleaning  it. 

In  1893,  the  mine  was  purchased  by  the  Hampden  Emery  and 
Corundum  Company  (as  it  is  now  styled),  and  the  material 
already  mined  was  hauled  to  Corundum  Hill  and  cleaned  with 
the  product  of  that  mine.  Since  that  time  a  little  prospecting 
has  been  done  in  the  chlorite  zones,  but  no  farther  mining;  has 
been  undertaken. 

The  nearest  practicable  shipping  point  is  forty  miles  away,  but 
by  the  construction  of  a  few  miles  of  wagon  road,  another  station 
could  be  reached  within  twenty  miles.     (See  also  page  69.) 

G.  THE  CORUNDUM  HILL  (CULLASAJA)  MINE,  MACON  COUNTY. 

This  mine  is  seven  miles  southeast  of  Franklin,  on  Cullasaja,  or 
Sugar  Fork  of  the  Little  Tennessee  river.  The  postoffice  is  Cul- 
lasaja. It  is  well  known,  not  only  for  being  the  first  worked,  but 
also  as  the  most  successful  corundum  mine  of  the  whole  belt.  Since 
1878,  it  has  afforded  a  constant  annual  product  of  200  to  300  tons 
of  cleaned  corundum.  During  1893-4,  the  output  was  not  so 
large,  but  the  mine  was  operated  continuously  during  a  period 
when  nearly  every  industry  of  the  country  was  paralyzed. 

The  beginning  of  operations  here  in  1871,  by  Col.  C.  AY.  Jenks, 
has  already  been  noted  in  the  sketch  of  "  Discoveries  and  early 
developments"  given  above.  This  first  mining  was  chiefly  for 
gems  ;  and  the  work  was  done  by  a  hydraulic  process  with  sluice 
boxes,  very  much  in  the  same  manner  as  the  process  is  applied  to 
gold  mining.  The  surface  soil  and  loose  vein  material  were 
washed  through  a  series  of  sluices,  or  rather  boxes,  inclined  about 
thirty  degrees.  The  material  was  constantly  stirred  so  as  to  allow 
the  lighter  minerals  to  float  off,  while  the  corundum  and  other 
heavy  minerals  remained  in  the  boxes.  The  concentrated  corun- 
dum thus  obtained  was  then  removed  and  carefully  searched  for 
gems.  Transparent  and  translucent  fragments  of  ruby-red,  sap- 
phire-blue, yellow,  green,  colorless,  and  other  shades  were  found. 
Some   of  these    cut   good  gems  ;  but,    unfortunately,    they    were 


NORTH    CAROLINA    CORUNDUM    MINES. 


93 


always  small  and  the  quantity  too  limited  to  make  the  business 
profitable. 

The  value  of  the  so-called  sand  corundum  was  not  then  realized  ; 
and  the  only  material  put  on  the  market,  besides  gems  and  cabinet 
specimens,  consisted  of  the  larger  crystals  and  lumps.  About  one 
hundred  tons  of  this  corundum  were  mined,  and  sold  for  dental 
and  other  purposes  in  this  country  and  Europe.  This  material, 
however,  possessed  a  degree  of  purity  scarcely  attained  in  the  later 
product  of  any  of  the  mines.  The  average  force  employed  in  this 
work  was  about  twelve  men. 

In  1878,  Dr.  H.  S.  Lucas,  of  Chester,  Massachusetts,  bought  the 
mine  at  Corundum  Hill  for  the  Hampden  Emery  Company,  and 
began  operations  in  October  of  the  same  year.  Profiting  by  the 
experience  of  his  predecessors,  Dr.  Lucas  confined  his  operations 
to  the  mining  of  corundum  for  abrasive  purposes  only;  and  all 
corundum  found — whether  sand,  crystals,  or  lumps — was  saved 
and  worked  into  sizes  together.  The  abundant  water-power  of 
the  Cullasaja  was  early  utilized  for  the  operation  of  washing  and 
other  cleaning  machinery  ;  and  thus  the  business  was  placed  on  a 
basis  which  has  continued  successful  to  the  present  time. 


a 


T-O: 


■4" 


mm 


[Fig.  6.— Diagramatic  section  across  the  corundum-bearing  zone  between  gneiss  and 
peridotite,  Corundum  Hill,  Macon  county,  a.  Gneiss,  sometimes  bearing  corundum  near 
the  border;  b,  Schistose  talc,  chlorite,  and  vermiculite;  c,  Chlorite  and  vermiculite  in 
interlocking  crystalline  plates  with  disseminated  corundum;  d.  Similar  to  l>  but  more 
talcose;  e.  Border  of  bladed  and  fibrous  enstatite;  /,  Dunite.  [For  a  description  of  the 
formations  illustrated  by  this  figure  see  page  55.] 


A  line  of  sluice  troughs  a  mile  and  a  half  in  length  connects 
the  mine  with  the  mill,  and  the  loose  chloritic  vein  material  is 
dumped  into  this  as   fast   as   mined.      The    rolling,   falling,    and 


94  CORUNDUM    AND    BASIC    MAGNESIAN    "ROCKS. 

scouring  action  to  which  it  is  subjected  over  this  course  does 
much  toward  separating  the  corundum  from  the  accompanying 
impurities,  and  it  arrives  at  the  mill  in  a  condition  which  renders 
cleaning  comparatively  easy.   (See fig.  6  [p.  93]  and  pp.  37  and  55.) 

For  two  or  three  years,  the  "  Hosea  Moses  mine  "  on  Eliijay 
creek  was  worked  by  the  same  company,  and,  after  a  partial  wash- 
ing at  the  mine,  the  product  hauled  to  Corundum  Hill  for  defin- 
ing.     This  was  closed  in  1894,  and  has  not  since  been  worked. 

Recently  Dr.  Lucas  has  retired  from  the  company,  and  the 
mines  are  under  the  management  of  the  new  president,  Mr.  Frank 
E.  Bidwell.  The  force  employed  in  the  company's  x^orth  Carolina 
mines  has  been  somewhat  variable,  but  it  is  usually  about  thirty 
or  forty.  The  company  (now  styled  the  Hampden  Emery  and 
Corundum  Company)  also  owns  the  Buck  creek  mine,  but  has  not 
yet  attempted  to  work  it  ;  also  the  Pine  Mountain  mine,  (Laurel 
creek,)  in  Rabun  county,  Georgia,  which  was  operated  from  18 SO 
till  the  spring  of  1893  ;  and  the  emery  mine  at  Chester,  Massa- 
chusetts, which  is  still  in  operation. 

d.  THK  SAPPHIRE  (HOGBACK)  MINKS,  JACKSON  COUNTY. 

Corundum  was  known  in  the  vicinity  of  Great  Hogback  moun- 
tain in  the  southeastern  corner  of  Jackson  county  atthe  time  when 
Dr.  Smith  wrote  his  report  on  this  region,  1875.*  He  speaks  of 
several  hundred  pounds  having  been  taken  out  by  digging  small 
pits. 

Work  was  begun  here  by  the  Sapphire  Valley  Mining  Company 
in  1892,  at  the  "  Burnt  Bock  "  mine,  seven  miles  northeast  of 
Sapphire  ;  and  shortly  afterwards  a  number  of  places  in  the  sur- 
rounding country  were  opened.  A  complete  cleaning  and  crushing 
plant  was  erected  on  Horsepasture  river,  and  considerable  expense 
was  incurred  in  building  roads,  bridges,  stores  and  other  houses, 
saw-mills,  shops,  etc.  About  fifty  or  sixty  men  were  constantly 
employed  in  mining,  prospecting,  and  improvements,  during  the 
year  in  which  the  mine  was  operated.  Mr.  Charles  N".  Jenks,  the 
superintendent,  reports  a  product  of  over  400  tons,  one-fourth  of 
which    was  crystal  corundum  90  per  cent.   pure.     Work  was   sus- 

*Rept.  Geol.  Sur.  N.  C,  1, 1875,  Appendix  91-97. 


NORTH    CAROLINA    CORUNDUM    MINES.  95 

pended  during  the  financial  crisis  of  1893,  and  has  not  yet  been 
resumed.  The  new  railroad  to  Brevard  will  affect  a  considerable 
saving  in  transportation,  as  the  product  was  formerly  hauled  on 
wagons  to  Henderson ville  for  shipment,  a  distance  of  some  forty 
miles.  (For  descriptions  of  the  various  workings,  see  pages  71 
and  72.) 

e.  THE  CARTER  MINE    MADISON  COUNTY. 

This  mine  is  in  the  eastern  corner  of  the  county,  near  Demo- 
crat postoffice,  in  Buncombe  county.  It  is  located  on  Holcombe 
branch,  a  tributary  to  Ivy  river,  and  marks  the  northern  extremity 
of  the  belt  of  dunite  which  extends  over  a  distance  of  more  than 
two  miles,  with  an  average  width  of  about  one-fourth  of  a  mile. 
Dr.  C.  D.  Smith  first  found  corundum  here  about  fifteen  or  twenty 
years  ago. 

The  first  work  was  done  by  Mr.  William  Carter  and  Dr.  H.  S. 
Lucas,  who  took  out  a  few  tons  in  prospecting.  Afterward  work 
of  a  similar  nature  was  done  by  Mr.  M.  E.  Carter,  and  by  Messrs. 
Rice  and  Coleman,  who  sold  the  property  to  Tarr,  Hamilton  and 
Company,  of  ISTew  York.  This  company  began  regular  mining 
about  1886.  A  steam  crushing  and  sizing  plant  was  erected  on 
the  grounds,  and  about  twenty  tons  of  corundum  were  cleaned  and 
shipped  from  Marshall.  The  work  continued  only  about  six 
months,  and  has  not  since  been  resumed.    (See  also  page  74.) 

/.  THE  ACME  MINE,  STATESVILLE,  IREDEEE  COUNTY. 

This  mine  is  located  about  three-fourths  of  a  mile  west  of  the 
town  of  Statesville,  and  half  a  mile  south  of  the  Charlotte  and 
Taylors  ville  Railroad.  About  1875,  Mr.  J.  A.  D.  Stevenson 
found  corundum  near  the  site  of  the  present  operations.  The 
Acme  Corundum  and  Mining  Company  began  work  here  in  Feb- 
ruary 1893  under  the  management  of  Mr.  H.  A.  Collins.  Some 
corundum  was  shipped  in  the  form  of  large  rough  blocks  and 
crystals,  just  as  it  came  from  the  mine  ;  but  this  was  soon  found 
unprofitable,  and  a  steam  mill  was  erected  in  March  of  the  same 
year  for  cleaning  and  crushing.  The  product  of  cleaned  material 
in   1893  was  about  fifty  tons. 

Considerable  difficulty  was  encountered  on  account  of  the  great 


96  CORUNDUM    AND    BASIC    MAGNESIAN    BOCKS. 

depth  of  soil  and  decayed  rock.  The  mine  is  situated  in  a  depression 
near  the  head  of  a  small  branch,  where  the  alluvial  deposits  of  clay 
are  about  fifteen  feet  deep.  This  material  and  the  soft  rock  under- 
lying it  are  so  thoroughly  saturated  with  water  that  great  diffi- 
culty was  experienced  in  holding  them  back  out  of  the  workings. 

Mining  was  resumed  in  December,  189i,  and  since  then,  the 
work  has  been  of  the  nature  of  prospecting  for  the  purpose  of 
locating  veins  under  more  favorable  conditions. 

The  mode  of  occurrence  of  this  corundum  and  that  of  the  Hun- 
ter place,  in  Iredell,  are  described  under  the  head  of  corundum 
in  amphibolite,  pages  58  and  59.      See  also  page  76. 

8.     OTHER  ECONOMIC  MINERALS  OF  THE  CORUNDUM  BELT. 

Incidentally  the  chromic  iron  and  asbestos  deposits  were  noted 
in  passing  over  the  region  on  the  corundum  work.  These  min- 
erals have  been  found  in  promising  abundance  in  many  places,  and 
hence  a  word  in  regard  to  them  is  appended  here.  "While  the  cor- 
undum shows  a  great  falling  off  northward,  this  is  by  no  means 
true  of  the  characteristic  accompaniments  of  peridotite — chromite, 
asbestos,  and  nickel  silicates. 

(1)   CHEOMITE,  OB  CHBOMIC  IEON. 

This  mineral  has  been  found  in  considerable  abundance  in  Jack- 
son county,  near  Webster;  in  Bum  combe  county,  at  Morgan  Hill; 
and  in  several  localities  in  Yancey,  Mitchell,  and  Watauga  coun- 
ties. For  analyses  and  more  definite  information,  the  reader  is 
referred  to  Bulletin  No.  1  of  the  present  Survey,  Iron  Ores  of 
North  Carolina,  by  H.  B.  C.  Nitze,  1893,  pages  212-215. 

(2)     ASBESTOS. 

A  fibrous  mineral  which  is  called  by  this  name  has  been  the 
object  of  considerable  interest  in  Jackson  county,  in  the  vicinity 
of  Glenville;  in  Mitchell  county,  near  Bakersville,  and  near  the 
mouth  of  Squirrel  creek  on  north  Toe  river;  in  Watauga  county, 


NICKEL-BEARING    MINERALS SERPENTINE.  97 

along  the  western  slopes  of  Rich  mountain;  in  Ashe  county,  on 
Elk  creek;  and  it  is  found  with  all  the  enstatite  rocks  of  the  north- 
eastern portion  of  this  belt.  Fibre  of  good  length,  color,  and  fine- 
ness has  been  found  in  many  places;  and  the  mineral  is  of  suffi- 
cient importance  to  warrant  further  investigation.  In  some  places 
this  fibrous  mineral  is  enstatite,  while  in  others  it  is  chrysotile,  or 
fibrous  serpentine.  In  a  few  cases  it  is  possibly  amphibole,  the 
true  asbestos. 

(3)    NICKEL-BEARING  MINERALS. 

Minute  quantities  of  nickel  are  often  present  in  the  olivine  rocks 
of  this  belt,  but  its  presence  can  scarcely  be  detected  in  the  fresh 
specimen  except  by  chemical  methods.  But  when  the  olivine 
begins  to  decompose  under  the  influence  of  the  atmospheric  agen- 
cies, it  is  readily  seen  in  the  characteristic  green  silicates  that  are 
developed  along  the  joints  and  fissures.  Genthite,  garnierite,  and 
perhaps  other  nickel  silicates  are  formed  in  such  relations  in  the 
dunite  at  Webster,  in  Jackson  county.  These  minerals  have  attrac- 
ted considerable  attention,  and  some  prospecting  has  been  done, 
but  nothing  of  importance  as  an  ore  has  yet  been  found. 

Similar  indications  of  the  presence  of  nickel  were  observed  south 
of  Shooting  creek,  near  Elf,  Clay  county,  and  south  of  Democrat, 
in  Buncombe  county.  Small  amounts  of  nickel  staining  have  been 
seen  in  many  places,  showing  a  wide  distribution  of  the  metal  in 
our  olivine  rocks;  but  no  other  localities  were  found  that  are 
considered  worthy  of  special  mention. 

(4)    SERPENTINE. 

Mention  has  already  been  made  (page  31)  of  the  adaptation  of 
the  serpentines  of  this  belt  to  architectural  purposes.  They  are 
indentical  in  every  respect  with  those  of  Maryland  and  Pennsyl- 
vania, which  are  largely  quarried,  especially  in  the  latter  state,  for 
both  interior  decorative  work  and  ordinary  building  purposes. 
The  dark  green  and  mottled  varieties  take  a  fine  polish  and 
give  very  rich  effects  for  ornamental  work  where  not  exposed  to 
wear  or  weather.      The  peculiar,  but  not  unpleasing  effect  of  the 


98  CORUNDUM     AND    BASIC    MAGNESIAN    ROCKS. 

lighter  colors  for  general  building  purposes  may  be  seen  in  many 
structures  in  Philadelphia,  Baltimore,  and  Washington. 

Outcrops  of  serpentine  well  suited  to  both  these  uses  occur  abun- 
dantly between  Weaverville  aud  Leicester,  in  Buncombe  county, 
in  the  strip  that  crosses  the  French  Broad  river  a  mile  above  Alex- 
ander. Other  masses  equally  as  large  are  found  on  the  Paint  Fork 
of  Ivy  river,  in  Madison  county,  and  on  the  waters  of  Bald  creek, 
in  Yancey  county;  but  these  are  not  so  conveniently  located  for 
transportation. 

There  seems  to  be  no  reason  why  the  Buncombe  county  serpen- 
tine should  not  come  into  the  market  in  the  near  future.  The  era 
of  substantial  building  has  only  just  begun  in  the  southern  states, 
and  as  we  learn  to  build,  we  should  also  learn  to  appreciate  and 
appropriate  our  own  resources. 


. 


LITERATURE    ON    THE    CORUNDUM    BELT.  99 


9.  LITERATURE  ON   THE  CORUNDUM   BELT. 

Only  references  pertaining  to  corundum  itself  or  the  corundum-bearing 
rocks  are  included  in  this  list.  Many  others  on  peridotites  and  serpentine 
might  be  added. 

Adams,  J.  H.     Corundum  at  Pelham,  Mass.   Am.  Jour.  Science,  2,  XLIX., 

1870,  271,  272. 
Beck,  Lewis  C.     Corundum  in  New  York.    Mineralogy  of  New    York, 

1842,  315. 
Blake,  W.  P.     Corundum,  etc.,  at  Vernon,  N.  J.   Am.   Jour.   Science,  2, 

XIII,  1852,  116. 
Chatard,  T.  M.     Corundum  and  emery  of  the  U.  S.     Min.   Resources  of 

the  U.  S.,  1883-84,  714-720. 
Gneiss-Dunite  contacts  of  Corundum  Hill,  N.  C.     Bull.  42,    U.  S.   Geol. 

Survey,  1887,  45-63. 
Cleaveland,  Parker.     Corundum  at  Litchfield,  Conn.  Mineralogy  and 

Geology,  Boston,  1822. 
Dana,  J.  D.     Emery  of  Cortlandt,  Westchester  county,  N.   Y.   Am.  Jour. 

Science,  3,  XX.,  1880,  199,  200. 
Day,  David  T.     Coruudum  and  emery  of  the  U.  S.     Min.  Resources  of 

the  U.  S.,  1885,  429  :  1887,  553,  554;  1888,  577;  1889-90,  457. 
Dickson,  John.     Corundum  from  the  Carolinas.    Am.  Jour.  Science,  1, 

III.,  1821,  4,  229,  230. 
Fowler,  Samuel.     Sapphire,  etc.,  at  Newton,  Sussex  county,  N.  J.   Am. 

Jour.  Science,  1,  XXL,  1832,  319,  320. 

Gannett,  Henry.     Corundum  and  emery  of  the  U.  S.   Min.  Resources  of 

the  U.  S.,  1882,  476,  477. 
Genth,  F.  A.     Corundum  in  N.  C.     Jour.  Franklin  Inst.,  Nov.  and  Dec. 

1871. 
Corundum,  alterations  and  associated  minerals.     Proc.  Am.  Phil.  Soc, 

XIII.,  1873,  361-406  ;  XIV.,  1874,  216-218  ;  XX.,  1882,  381-404. 

Corundum  in  Pennsylvania.     2nd  Geol.  Survey  of  Penn.,  B,  1875,  31-33. 

Corundum  in  N.  C.     Rept.  Geol.  Survey  of  N.  C,  I.,  1875,  Appendix,  64. 

— — and  W.  C.  Kerr.     Emery  in  Guilford  county,  N.  C.     Rept.  Geol.  Sur- 
vey of  N.  C,  I.,  1875,  246. 
Corundum  in  Patrick   county,  Va.      Am.  Jour.  Science,   3,   XXXIX., 

1890,  47,  48. 

Corundum  in  N.  C.     Bull.  74,  U.  S.  Geol.  Survey,  1891,  29-31. 

Hitchcock,    Edward.      Corundum     at     Litchfield,    Conn.      Am.    Jour. 

Science,  1,  VI.,  1823,  219. 
Hunt,  T.  Sterry.     On  Dr.  Genth's  researches  on  Corundum.     Proc.  Nat. 

Hist.  Soc,  Boston,  XVI.,  1874. 
Hunter,  C.  L.     Corundum    and    emery  in  Gaston   county,  N.    C.     Am. 

Jour.  Science,  2,  XV.,  1853,376. 


100  CORUNDUM    AND    BASIC    MAGNESIAN     ROCKS. 

Jackson,  C.  T.     Discovery  of  emery  at  Chester,  Mass.     Am.  Jour.  Science, 

2,  XXXIX,  1865,  87-90. 
Discovery  of  corundum  at  the  emery  mine,  Chester,  Mass.     Am.  Jour. 

Science,  2,  XLII.,  1866,  421. 
Jenks,   Charles  N.     Abrasives  in   common   use.      Scientific    American 

Sup.,  No.  988,  Dec.  8,  1894. 
Jenks,  C.  W.     Corundum  in  N.  C,   Am.  Jour.  Science,  3,  III,   1873,  301, 

302.  Quar.  Jour.  Geol.  Soc,  London,  XXX.,  1874,  303-306. 
Julien,  A.  A.     Dunite  beds  of  N.  C,  Proc.  Nat.  Hist.  Soc.  Boston,  XXII., 

1882,  141-149. 
Kerr,  W.  C.     Corundum  of  N.  C,  Kept.  Geol.   Survey  of  N    C,    I.,  1875, 

299.    Appendix  Rept.Beol.  Sur.  of  N  C,  1873,  9. 
King,  Francis  P.    Corundum  in  Gra.,  Bull.  2,  Geol.  Survey  of  Ga.,  1894. 
Kunz.  George  F.  Corundum  gems  of  the  U.  S.  Min.  Resources  of  the  U.  S., 

1882,  485,  486;  1883-84,  733-736;  1892,  760-761;  1893,  680.  Gems  and  Pre- 
cious Stones  of  North  America,  1890,  40-48. 
Lesley,  J.  P.     Origin  of  Corundum,  etc.,  in  Penn.,  2d   Geol.   Survey  of 

Penn.,  C4,  1883,  351-354. 

Lewis,  J.  Volney.  Origin  of  peridotite  and  Corundum  of  the  southern 
Appalachians.     Jour.  Elisha  Mitchell  Sci.  Soc,  12th  year,  1895-6. 

Corundum  of  the  Appalachian   Crystalline  Belt.     Trans.  Am.   Inst., 

Min.  Eng.,  XXV.,  Atlanta  meeting,  1895. 

Paret,  T.  Dunkin.     Emery  and  other  abrasives.  Jour.  Franklin  Inst., 

CXXXVIL,  1894,  353-372,  421-438. 
Parker,  E.  W.     Corundum  of  the  U.  S.     Min.   Resources  of  the    U.  S., 

1891,  555;  1892,  751. 

Corundum  in  N.  C.     Min.  Resources  of  the  U.  S.,  1893,  674  678. 

Pennypacker,  Charles  H.     Corundum  in  Penn.   Mineral  Collector,  II.. 

1895,  89,  90. 
Raborg,  William  A.     Corundum  of  the  U.  S.     Mineral  Resources  of  the 

U.  S.,  1886,  585,  586. 
Rand,  Theodore  D.,  W.   W.  Jefferis,   and    J.  T.  M.  Cardeza.    Min- 
eral localities  of    Philadelphia  and  vicinity.     Proc.  Ac.  Nat.  Sci. 

Phil.,  1892, 174-202. 
Origin  of  serpentine  of  Pennsylvania.     Proc.  Ac.  Nat.   Sci.  Phil.,  1890, 

76-123. 
Raymond,  R.  W.     Jenks  (Corundum  Hill)  mine,  N.  C.     Trans.   Am.   Inst. 

Min.  Eng.  VII.,  1878,  83-90. 
Shepard,  C.  U.     Corundum  at  Litchfield,  Conn.    Minerals  of  Conn.,  1837, 

64. 
Corundum  regions  of  N.  C.  and  Gra.     Am.  Jour.  Science,   3,   IV..  1872, 

109-114,  175-180. 


LITERATURE    ON    THE    CORUNDUM    BELT.  101 

Emery  and  associated  minerals  at  Chester,  Mass.     Am.   Jour.  Science, 

2,  XL.,  1865,  112,  123;  2,  XLIL,  1866,  421,  422;  2,  XLVL,  1868,  256. 
Silliman  B.,  Jr.     Corundum  and  associated  minerals,  Unionville,   Penn. 

Am.  Jour.  Science,  2,  VIII.,  1849,  377,  393. 
Smith,  C.  D.     Corundum  in  N.  C.     Rept.    Qeol.  Survey  of  N.  C,   I,   1875, 

Appendix,  91-97;  98-120. 
Smith,  Edgar  F.     Discovery  of  corundum  in  Lehigh  county,  Penn.     Proc. 

Am.  Phil.  Soc,  XXII.,  March,  1882. 
Analysis  of  corundum  from  Lehigh  county,  Penn.     Am.  Chem.  Jour. 

V.,  1883,  275. 
Smith,  J.  L.     Emery  of  Chester,  Mass.     Am.  Jour.  Science,   2,  XLIL,  1866, 

83-93. 
Corundum  in  N.  C,   Ga.  and  Mont.     Am.  Jour.  Science,  3,  VI.,  1873, 

180-186. 
Trautwine,  J.  C.     Corundum,   etc.,  Cullasaja  (Corundum   Hill),  N.   C, 

Jour.  Franklin  Inst,  XCIV.,  1872,  7. 
Wadsworth,  M.  E.     Olivine  rocks  of  N.  C,  Science,  III.,  1884,  486,  487. 
Dunite  of  N.  C.     uLithological  Studies,'''1  Mem.  Mus.  Comp.  Zool.,  Cam- 
bridge, XL,  Part  1, 1884,  118-120. 
Willcox,  Joseph.     Corundum  in  North  and  South  Carolina.  Proc.  Acad. 

Nat.  Sci.  Phil.,  1878,  159,  223. 
Corundum  in  Penn.     2d  Qeol.  Survey  of  Penn.,  C4.  1883,  346-351. 

Williams,  G.  H.     Emery   of  the   "  Cortland  series,"  N.   Y.      Am.    Jour. 

Science,  3,  XXXIII,  1887,  194-199. 
Miscellaneous  mention. — Corundum  in  N.  J.     Am.  Jour.  Science,  1,  XIIL, 
1828,  380. 

Corundum  Hill,  N.  C.     Am.  Jour.  Science,  3,  III.,  1872,  301. 
Corundum  in  N.  C.     Pop.  Science  Monthly,  IV.,  1874,  452-456. 
Corundum  in  S.  C.     Agr.  Rept.  S.  C.  1883,  137,  and  map. 
Corundum  in  Ga.     The  Commonwealth  of  Ga.,  1885,  139. 


102  CORUNDUM    AND    BASIC    MAGNESIAX    ROCKS. 


EXPLANATION  OF  PLATE  YI. 


PHOTOMICROGRAPHS  OF  THIN  SECTIONS  OF  DUNITE. 

Photographed  with  Fetiss''  objective  No.  0.  Magnified  12  diameters. 

FIGURE  1. — RAIUROAD  CUT  2  M.  WEST  OF  BALSAM  GAP,    JACKSON  COUNTY. 

This  is  an  exceptionally  fresh  specimen  of  the  pure  olivine  type.  The 
perfectly  crystalline,  even  grained  texture  of  the  rock,  and  the  generally 
irregular  (hypidiomorphic)  structure  are  well  shown ;  though  crystal  out- 
lines, like  that  on  the  upper  left  hand  side,  are  frequently  seen. 

FIGURE  2. — CARTER  CORUNDUM  MINE,  MADISON  COUNTY. 

This  figure  represents  the  prevailing  character  of  the  surface  exposure 
of  dunite.  These  first  narrow  bands  of  yellowish  green  serpentine  formed 
about  the  borders  of  the  olivine  grains  are  minutely  fibrous,  with  the 
fibres  at  right  angles  to  the  boundaries  of  the  olivine.  They  look  very 
much  like  mortar  in  rubble  masonry. 

FIGURE  3. — CARTER  CORUNDUM  MINE,  MADISON  COUNTY. 

This  section  shows  a  common  type  of  fine  grained  olivine  rock  as  seen 
between  crossed  nicols  (polarized  light).  The  minute  grains  are  found  to 
extinguish  together  over  considerable  areas,  showing  that  the  fine  text- 
ure is  the  result  of  irregular  cracking  up  of  large  grains  similar  to  those 
shown  in  figure  1. 

FIGURE  4. — WEBSTER,  JACKSON  COUNTY. 

This  specimen  shows  an  advanced  stage  in  the  alteration  of  olivine  to 
serpentine,  the  beginning  of  which  was  seen  in  figure  2.  In  the  process  of 
alteration,  a  considerable  proportion  of  magnetite  has  been  formed  and 
deposited  in  dark  bands  about  the  olivine  remnants,  which  appear  white 
in  the  figure. 

FIGURE  5. — PAINT  FORK  OF  IVY  RIVER,  MADISON  COUNTY. 

Here  we  have  the  final  result  of  the  process  of  serpentinization  repre- 
sented in  figures  2  and  4.  No  trace  of  unaltered  olivine  remains.  The 
positions  of  the  last  fragments  to  disappear  are  marked  by  black  accumu- 
lations of  magnetite;  otherwise  the  serpentine  appears  quite  homogeneous 
in  ordinary  light. 

FIGURE  6. — SAME  AS  FIGURE  5. 

The  subject  of  this  figure  is  identical  with  the  last,  except  that  the 
section  is  here  viewed  between  crossed  nicols.  The  network  of  light 
bands  ("mesh-structure")  represents  the  first  serpentine  formed  in  the 
alteration  of  olivine,  as  shown  in  figure  2,  and  marks  the  boundaries  of 
the  original  grains.    (This  figure  is  inverted  with  reference  to  figure  5.) 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  11.  PLATE  VI. 


THIN    SECTIONS   OF    DUNITE.      (Magnified    12    Diameters'. 


INDEX. 


Acme  corundum  mine,  Iredell  Co. 
Actinolite  in  amphibolite 

in  anaphibole-picrite.... 

in  dunite 

in  talc 

Adams,  F.  D.,  cited 

Adams,  J.  EL,  cited 

Addie,  Jackson  Co.,  corundum 

peridotite 


PAGE. 

95 


23 


Alabama,  corumdum 38,64 

peridotite 33,  64 

Alexander,  Buncombe  Co.,  serpen- 
tine    41, 98 

Alexander  Co.,  corundum 76,  89 

Alleghany  Co.,  peridotite 47 

soapstone 47 

Alluvial  deposits,  corundum  in 62 

Alterations  of  dunite 20,  56,  102 

of  peridotite 20,56 

of  pyroxenite 26 

Amphibole 20,  23,  25,  26,  59,  60 

Amphibole-picrite 23 

Amphibolite 28,  58 

Analyses  of  enstatite 27 

of  emery,  Guilford  Co 78 

of  feldspar  in  f  orellenstein  24 

of  "smaragdite" 29 

Andalusite 61 

Anorthite  in  amphibolite.. 28,  58 

in  forellenstein 24 

Anthophyllite 26,  56 

Apophyses  of  peridotite 36,  38 

Appalachian  crystalline  belt 12,33 

Asbestos 45,  69,  73,  96 

Ashe  County 97 

Jackson   " 96 

Mitchell    "     45,  75,  96 

Watauga"     45,96 

Ashe  Co.,  asbestos 97 

peridotite 46 

soapstone 32,  47 

Asia  Minor,  emery 88 

Asteria,  asteriated  sapphire 50,  52 

Bakersville,  asbestos 96 

corundum 75 

peridotite 44 

Bailey,  John  and  Joel,  corundum  in 

Penn .-. 87 

Balsam  Gap,  peridotite 38 

Banks  creek,  peridotite 43 

Baskerville,  Dr.  Chas.,  analyses  by.  24,  26,  29 

Beck,  Lewis  C,  cited 88 


PAGE. 

Behr  corundum  mine,  Clay  Co 91 

Bell  knob,  peridotite 35 

Bellevue,  peridotite 45 

Bid  well,  Frank  E.,  corundum  mining  94 

Blake,  W.  P.,  cited 88 

Block  corundum 52 

Boone,  Watauga  Co.,  chromite 19,  96 

peridotite 45 

Bowman,  D.  A.,  cited 75 

Bowman,  Wm.,  corundum 75 

Brace,  John  P.,  cited 87 

Brush  creek,  peridotite 47 

Bryson,  Major,  corundum  mining....  91 

Buck  creek,  amphibole-picrite 24 

amphibolite 28,  36,  55 

corundum  mine 69,  83,  91 

forellenstein 24,  36 

peridotite 15,  34,  36 

serpentine 30 

Buncombe  Co.,  chromite : 96 

corundum 73 

nickel-bearing  min- 
erals   40 

peridotite 40 

serpentine 30,  40 

Burke  Co.,  corundum 63,  77 

Burnsville,  chromite 19,  43 


Cane  creek,  Jackson  Co.,  peridotite. 
websterite 

Cane  creek,  Mitchell  Co.,  peridotite.. 

Caney  fork,  corundum 

Cai'bonates  in  dunite 21, 

Carpenters  knob,  corundum 

Carter,  John  A.,  acknowledgements 
corundum 

Carter  corundum  mine,  Madison  Co.  41,  74, 

Chalcedony  from  peridotite 22, 

Chatard,  T.  M.,  cited 

Chatham  Co.,  corundum 

Cherokee  Co.,  corundum 

Chester,  Mass.,  emery  mine tit;,  80, 

Chestnut  mountain,  dunite 

Chlorite 

in  amphibole-picrite 

in  dunite 20,  21, 

veins  of  with  corundum 55, 

Chlorite  schist 

corundum  in 33, 

Chloritoid 

Chromite,  chromic  iron 19. 

in  peridotite 17,  18, 

relation  to  picotite 


104: 


INDEX. 


Chrysolite,  see  Olivine. 

Chrysotile 97 

Chubbs  mountain,  corundum 77 

Chunky  Gal  mountain,  corundum-...  62,  68 

peridotite 35 

Clay  Co.,  corundum 67,91 

nickel-bearing  minerals....  97 

peridotite 24,  a5 

Cleaning  corundum,  methods 81,  83 

Cleveland  Co.,  corundum 77 

Cleveland,  Parker,  cite  i 87 

Clingman,  Gen.  T.  C, 88 

Collins,  H.  A.,  corundum  mining 95 

Commercial  corundum 50,  52 

Concentration  of  corundum 81 

natural 62 

Connecticut,  corundum 66 

Corundum,  character  and  varieties.  48 

in  North  Carolina.  51 

as  rock  constituent 54 

cleaning  processes 81,  83 

discoveries  and  early  de- 
velopments   87 

distribution 63 

in  Alabama 33,64 

Alexander  Co.. 76,89 

Appalachian  belt 63 

Buncombe  Co 73 

Burke  Co 63,77 

Chatham  Co 78 

Cherokee  Co 78 

Clay  Co 67,91 

Cleveland  Co. 77 

Connecticut 66 

Forsyth  Co 78 

Gaston  C  > 77,88 

Georgia 33,  64 

Guilford  Co 77,  89 

Haywood  Co 73 

Iredell  Co 58,76,89,95 

Jackson  Co 57,  63,  70 

Macon  Co 69,92 

Madison  Co 74,  88,  95 

Massachusetts 34,  66 

Mitchell  Co 75 

New  Jersey 65,  88 

New  York 34,  66  ,88 

North  Carolina.  33,  64,  67,  88 

Pennsylvania 33,65 

Polk  Co 78 

South  Carolina 33,  64 

Transylvania  Co 72 

Virginia 65 

Wilkes  Co 78 

Yancey  Co 75 

mining  methods 81,82 

modes  of  occurrence 54,  93 


page. 
Corundum— Continued. 

prospecting  methods 78 

uses  of 51 

Corundum  belt,  geologic  sketch 11 

Corundum  gems 50.  52 

Corundum  Hill  mine 37,  92 

cleaning  methods....  85 

Corundum  mining,  historical  sketch  86 

in  North  Carolina  89 

methods  of 81,82 

Corundum  wheels 51 

Cowee  mountains,  corundum 70 

Crab  creek,  peridotite 47 

Cranberry,  peridotite  near 45 

Crisp, Hiram,  discovery  of  corundum  88 

Crowders  mountain,  corundum 77 

Cullakanee  mine,  see  Buck  Creek. 
Cullasaja  mine,  see  Corundum  Hill. 
Cyanite,  corundum  in 61,  73,  74.87 

Damourite  on  corundum 76 

Dana,  James  I).,  cited 28.50 

Delafleld,  Maj.,  cited 87 

Democrat,  corundum  near 73 

nickel-bearing  minerals.  41,  97 

peridotite 40 

Deer  Island,  Me.,  serpentine 34 

Diallage  in  dunite 19 

Diaspore  with  corundum 56.  88 

Dickson,  John,  chW 87 

Dikes  of  amphibolite 28 

hypersthenite 61 

Discoveries   and   developments    of 

corundum 87 

Distribution  of  peridotite,  ere. 33 

of  corundum,    see   Co- 
rundum. 

Dunite 17,  43 

alteration  of 20,56,102 

corundum  in 60.  75 

distribution,  see  Peridotite. 

microscopic  characters 18. 102 

Economic  minerals  of  corundum  belt  96 

Edenite 28 

Egypt  (Hayes)  mine,  Yancey  Co 44,  75 

Elf,  Clay  Co.,  corundum 68,  91 

nickel-bearing  minerals...  97 

peridotite. 35 

Elk  creek,  Ashe  Co.,  harzburgite 46 

Elk  ridge,  Ashe  Co.,  peridotite 47 

Emerson,  B.  K.,  cited 67 

Emery 11,  50,  88 

Chester,  Mass. 66,  80 

Forsyth  Co 78 

Gaston  Co ".  88 

Guilford  Co 77,89 


;";.•-.  -.  - 


INDEX. 


105 


PAGE. 

Emery— Continued. 

New  York 34,66 

Emery  wheels 51 

Ennis,  Alleghany  Co.,  peridotite 47 

Enstatite  in  peridotites 19,  23,  25,  47 

in  pyroxenites.. 25 

Enstatite  borders 21,  56 

Enstatite  rock.  25,  45,  46 

analyses  of.... 27 

Feldspar  in  amphibolite 29 

in  forellenstein 24 

with  corundum 59,  74,  76,  83 

Fish  Hawk  mountain,  corundum 69 

Flat  creek  mountains,  peridotite 41 

Forellenstein,  troctolite 24,  35 

Forsyth  Co.,  corundum  and  emery...  78 

Fowler,  Dr.  Samuel,  cited 87 

French  Broad  river,  peridotite 39,  42 

serpentine 31,  41,  98 

Friendship,  emery  near 77 

Garnet 46,  62,  73 

Garnierite 97 

Gaston  Co.,  corundum... 77,  88 

Gem  varieties  of  corundum 50,51 

Genth,  Dr.  F.  A.,  cited. 10,  27, 28,  56,  61, 77,  78,  89 

Genthite 97 

Geologic  sketch  of  corundum  region  11 

Georgia,  corundum  in 33,  64 

peridotite 34,  36,  39 

Glade  creek,  peridotite 47 

Glenville,  Jackson  Co.,  asbestos 96 

peridotite 39 

Gneiss,  corundum  in 61,  73 

of  the  crystalline  belt 12,  55 

Gravel  deposits,  corundum  in 62 

Grimshawe,    Dr.    C,   acknowledge- 
ments   91 

Guilford  Co.,  emery 77,  89 

Hamilton  corundum  mine,  Georgia.  35 

Hampden  Emery  and  Corundum  Co.  92,  94 

Hart,  Gregory,  corundum  mining....  91 

Harzburgite  (Saxonite) 23,  43,  46,  47 

Hayes  (Egypt)  mine,    Yancey  Co....  44,  75 

Hayes,  U.  S.,  acknowledgements 91 

Haynie,  G.  C,  corundum 75 

Haywood  Co.,  corundum 73 

peridotite 40 

Historical  sketch  of  corundum  m'n'g  86 

Hitchcock,  Edward,  cited 66,  87 

Hoboken,  N.  J.,  serpentine 34 

Hogback  (Sapphire)  corund1m  mine  39, 71, 94 

Hogsed,  Samuel,  corundum 68 

7 


PAGE. 

Hornblende,  see  Amphibole. 

"  Hosea  Moses  Mine,"  Macon  Co 94 

Hunter,  Dr.  C.  L.,  cited 77,  88 

Hypersthenite  dikes 61 

Igneous  rocks,  sheared 12 

"Indications"  of  corundum 78 

Iredell  Co.,  amphibolite 58 

corundum 58,76,89,95 

Ivy  river,  corundum 75,  95 

peridotite 42 

serpentine 31,42,  98 

Jackson  Co.,  asbestos 96 

chromite 19,  96 

corundum 57,  63*  70,  94 

nickel-bearing  min'r'ls  97 

peridotite 37 

Jackson,  Dr.  C.  T.,  cited 88 

Jefferis,  W.  W.,  cited 87 

Jefferson,  soapstone 47 

Jenks,  Chas.  N.,  acknowledgements  71.  90,  94 
Jenks,  Col.  C.  W.,  corundum  mining.     89,  92 

Julian,  Frank,  analysis  by 27 

Julien,  A.  A.,  cited .. 10 

Kings  mountain,  corundum 77 

King,  Francis  P.,  cited 26,28,35,  65 

Kunz,  George  F.,  cited . 51,52,64 

Laurel   creek   (Pine  mountain)    co- 
rundum mine,  Georgia 39,  64,  83 

Leicester,  serpentine 40,  98 

Lewis,  J.  Volney,  cited 31 

Limestone,  corundum  with 66,  88 

Literature  on  corundum  belt. 99 

Litchfield,  Conn.,  corundum 87 

Lucas,  Dr.  H.  S.,  acknowledgements     88,  90 
corundum  mining  91, 93, 95 

McChristian  place,  emery 77 

McDowell  Co.,  corundum 63 

Macon  Co.,  corundum 37,  69,92 

peridotite 36 

Madison  Co.,  corundum 74,  88,  95 

peridotite 41 

serpentine 30,  41,  98 

Magnesian  rocks 13,15 

Magnetite 21,  46, 102 

Maine,  serpentine 34 

Map  of  Appalachian  crystalline  belt  32 

Buck  creek  peridotite  area...  34 

Corundum  Hill 36 

Webster  peridotite  area 38 

Western  N.  C.    Frontispiece. 


106 


INDEX. 


PAGE. 

Margarite  with  corundum.  56, 59, 73,  76,  80, 88 

Marshall,  corundum  discovery 74,  88 

Maryland,  corundum 65 

serpentine 31,  33,  97 

Massachusetts,  corundum,  emery  ...66,  88,  89 

peridotite 34,67 

serpentine 34 

Massive  rocks  of  peridotite  belt 13, 15 

Meminger,  Frank,  mining 91 

Mesh  structure  of  serpentine 102 

Methods  of  cleaning  corundum 81,  83 

mining  81, 82 

prospecting  78 

Mica  with  corundum 56.58,60,  61 

Mica  schist,  corundum  in 61,  64,  73 

Microscopic  characters  of  dunite 18, 102 

serpentine         102 

Mining  and  cleaning  methods 81 

Mitchell  Co.,  asbestos 45,  75,  96 

chromite 96 

corundum 75 

peridotite 44 

Modes  ofoccurrence  of  corundum....     54,  93 

Monazite 77 

Morgan  Hill,  chromite £6 

Muscovite 58,58,60,61 

New  Found  creek,  serpentine 40 

New  Found  gap,  corundum 73 

peridotite 40 

New  Hampshire,  serpentine 34 

New  Jersey,  corundum 87,  88 

serpentine 34 

New  York,  corundum  and  emery...  34,  66,  88 

peridotite 34,  66 

serpentine 34 

New  Zealand,  dunite 17 

Nickel-bearing  minerals 22,  44,  97 

Nitze,  H.  B.  C,  acknowledgements  .  77 

cited 96 

North  Toe  river,  asbestos 96 

peridotite 45 

Norwich,  Conn.,  corundum 66 

Ocoee  formation 14,  45 

Olivine,  alterations,  etc 20, 102 

in  forellenstein : 24 

in  peridotite 15 

serpentine  from 30, 102 

Oriental  amethyst 50 

emerald 50 

ruby 50,  52 

topaz  50 

Paint  Fork  of  Ivy  river,  serpentine.     42,  98 

Paleozoic  of  Tennessee 14 

Pegmatite  with  corundum 57,  73 


PAGE. 

Penland,  Newton,  corundum 68 

Pennsylvania,  corundum 33,  65 

serpentine 31.  33 

"  Perido-steatite  " 42,  44 

Peridotite  and  associated  rocks 13, 15 

corundum  with 55 

distribution'in  Alabama 33,  64 

Alleghany^Co 47 

Appalachian  belt 33 

Ashe  Co 46 

Buncombe  Co 40 

Clay  Co 35 

Georgia 33, 36, 39,  64 

Haywood  Co 40 

Jackson  Co 37 

Macon  Co 36 

Maine 34 

Madison  Co 41 

Maryland 33.  97 

Massachusetts 34.  67 

Mitchell  Co 44 

New  Hampshire 34 

New  Jersey 34,66 

New  York 34,66 

North  Carolina 34, 64, 67 

Pennsylvania 33,  65 

South  Carolina 33.  64 

Transylvania  Co 39 

Vermont 31 

Virginia 33,  65 

Watauga  Co 45 

Yancey  Co 43 

Picotite  in  amphibole-picrite 23 

amphibolite 29,  58 

dunite 17. 18 

relation  to  chromite 18 

Pigeon  river,  corundum 73 

Pine  mountain  (Laurel  creek)  corun- 
dum mine,  Georgia 39.  64.  83 

Pine  Swamp  creek,  peridotite 47 

Polk  Co.,  corundum 78 

Presley  corundum  mine,  Hayw'd  Co.  40,  73 

Prices  creek,  peridotite. 43 

Prospecting  methods 78 

Pyrite  with  corundum 87 

Pyrophyllite,  corundum  in 78 

Pyroxene 56 

in  harzburgite 23 

in  pyroxenites 25,27 

Pyroxenites 25,  45,  46 

Rabun  Co.,  Georgia,  corundum 39 

peridotite 36 

Reaction  zones  in  forellenstein 25 

Rich  mountain,  chromite 45 

peridotite 45 

Ropes,  L.  S.,  acknowledgements 91 


INDEX. 


107 


PAGE. 

Ruby,  oriental  or  true 50,  52 

Rutherford  Co.,  corundum 63 

Sampson  mountains,  corundum 75 

peridotite 44 

Sand  corundum 52 

Sapphire 50 

Sapphire  (Hogback)  mine 39,  71,  83,  94 

cleaning  methods 84 

Saxonite  (Harzbui  gite) 23,  43,  46,  47 

Scaly  mountain,  corundum 69 

Schistose  magnesian  rocks 32 

Seal,  Dr.  Thomas,  corundum  in  Penn  87 

Secondary  minerals  in  dunite 20 

Secondary  magnesian  rocks 30 

Serpentine..... 20,30,  97 

architectural  uses 31,  97 

derived  from  olivine 20,  30 

distribution,  Buck  creek  30 

Buncombe  Co 30,  40 

Clay  Co 30 

Madison  Co 30 

Maine 34 

Maryland 31,33,97 

Massachusetts 34 

New  Hampshire..  34 

New  Jersey 34 

New  York 34 

Pennsylvania 31, 33, 97 

Vermont 34 

Virginia 33 

Watauga  Co 46 

Yancey  Co 30 

Sheared  igneous  rocks 12 

Shepard,  Dr.  C.  IT.,  cited 10 

Shooting  creek,  corundum 61,  68,  91 

nickel-bearing'minerals..  97 

peridotite 24,  35 

Smaragdite 28 

Smith,  Dr.  C.  D.,  cited 26,60,91,94 

Smith,  Dr.  J.  L.,  cited 88 

Soapstone,  talc  rocks 32,  42 

Alleghany  Co 32 

Ashe  Co 32,  47 

Watauga  Co 46 

South  Carolina,  corundum 33,64 

South  Toe  river,  peridotite 44 

Spinel  with  corundum . 56,66,  74 

Star  sapphire 50,  52 

Staten  Island,  serpentine 34 

Statesville,  corundum 76,  95 

Staurolite 56 


PAGE. 

Stephenson,  J.  A.  D.,  acknowledge- 
ments   89, 91 

Stoner,  A.  M.,  acknowledgements....  91 

Swannanoa  gap,  corundum 74 

Talc  from  enstatite 26 

in  dunite 21 

Talc  rocks,  soapstone 13,  32,  42,  46,  73 

Tourmaline  with  corundum 56 

Towns  Co.,  Georgia,  corundum 34,  64 

peridotite 34 

Toxaway  river,  corundum 73 

Track  Rock  corundum  mine,  Ga 34 

Transylvania  Co.,  corundum 72 

peridotite 39 

Tremolite  in  dunite 21 

Troctolite,  Forellenstein 24 

Turkey  knob,  corundum 70 

Union  Co.,  Georgia,  corundum 34 

Uses  of  corundum 51 

Varieties  of  corundum 48,  51 

Vermiculite 57,  59,  76 

Vermont,  serpentine 34 

Vernon,  N.  J.,  corundum 88 

Virginia,  corundum 61,  65 

peridotite 47 

serpentine 33 

Wadsworth,  Dr.  M.  E.,  cited, 19 

Ward,  E,  B.,  corundum  mining 89 

Watauga  Co.,  asbestos 45,  96 

chromite 19,  96 

peridotite 45 

Weathering  of  dunite 22 

Weaverville,  serpentine 98 

Webster,  chromite 19,96 

nickel-bearing  minerals....  97 

peridotite 15,17,  34,  37 

Websterite 27 

Wilkes  Co.,  corundum 87 

Willcox,  Joseph,  cited 78 

Williams,  Dr.  G.  H.,  cited 9,  27,  66 

Yancey  Co.,  chromite 19,  96 

corundum 75 

peridotite 43 

serpentine 30,  98 

Zirkel,  F.,  cited 54 


HISTORY  OF  THE  GEMS  FOUND  IN 
NORTH  CAROLINA 


BY 

GEORGE  FREDERICK  KUNZ,  Ph.D. 


I 


i 


NORTH  CAROLINA  GEOLOGICAL  AND 
ECONOMIC  SURVEY 

JOSEPH  HYDE  PRATT,  STATE  GEOLOGIST 


BULLETIN  NO.  12 


HISTORY  OF  THE  GEMS  FOUND  IN 
NORTH  CAROLINA 

GEORGE  FREDERICK  KUNZ,  Ph.D. 


RALEIGH 

E.  M.  Uzzell  &  Co.,  Public  Printeks  and  Binders 

1907 


\ 


A 


r 


b'bl 
/|/f/2> 


4_ 


GEOLOGICAL  BOARD 


Governor  R.  B.  Glenn,  ex  officio  Chairman Raleigh. 

Henry  E.  Fries Winston-Salem. 

Frank  R.  Hewitt Asheville. 

Hugh  MacRae Wilmington. 

Frank    Wood Edenton. 

Joseph  Hyde  Pratt,  State  Geologist Chapel  Hill. 


t 


LETTER  OF  TRANSMITTAL 


Chapel  Hill,  N.  C.,  November  15,  1906. 

To  His  Excellency,  Hon.  E.  B.  Glenn, 

Governor  of  North  Carolina. 

Sir. — I  have  the  honor  to  submit  for  publication  as  Bulletin  No. 
12  of  the  Geological  and  Economic  Survey,  the  report  of  Dr.  George 
Frederick  Kunz  on  the  History  of  the  Gems  found  in  North  Carolina. 

Yours  obediently, 

Joseph  Hyde  Pratt, 

State  Geologist. 


L 


CONTENTS 


PAGE 

Peeface    ix 

Introduction    xl 

Chapter       I. — Historical  sketch  of  gem  mining  in  North  Carolina 1 

II. — Diamonds     5 

III. — Corundum  gems  10 

IV. — Gem  minerals  of  the  pegmatite  dikes 25 

The  feldspars  27 

Orthoclase     27 

Microline     27 

Oligoclase    27 

Labradorite  28 

Leopardite    28 

V— Quartz    29 

Crystalline  varieties 29 

Rock  crystal   29 

Amethyst     81 

Smoky  quartz 32 

Rose  quartz    33 

Quartz  inclusions    33 

Fluid  inclusions    34 

Non-Crystalline  quartz    35 

Chalcedony    35 

Chrysoprase    35 

Jasper     35 

Opal     36 

Hyalite     36 

VI. — Beryl,   spodumene    (hiddenite) 37 

Beryl     37 

Emerald  beryl   37 

Aquamarine    42 

Yellow  beryl    42 

Hiddenite  or  lithia  emerald 45 

VII. — Garnet,  zircon,  rutile,  octahedrite 49 

Garnet    49 

Almandite     49 

Pyrope    50 

Rhodolite     50 

Zircon  51 

Rutile     52 

Octahedrite     53 

VIII. — Cyanite,  epidote,  tourmaline,  chrysolite  (peridot),  ser- 
pentine, SMARAGDITE,  LAZULITE,  MALACHITE,  PEARLS..  54 

Cyanite     54 

Epidote 55 

Tourmaline     55 

Chrysolite    (peridot) 56 

Serpentine     56 

Edenite  (smaragdite)    57 

Lazulite    57 

Malachite    58 

Pearls     58 


ILLUSTRATIONS 


PLATE  FACING   PAGE 

I.     Corundum  gems  from  North  Carolina « 1 

II.    Wiseman   Beryl   Mine,   Mitchell   County,   N.   C,   18   miles   from 

Marion    2 

III.  Diamond  and  heryl  crystals  from  North  Carolina 8 

IV.  A,  Transparent  blue  and  green   sapphire,   natural   size,  Macon 

County,  N.  C;  B,  Corundum  showing  alteration,  natural  size, 

Haywood  County,  N.  C 16 

V.     Quartz  gems  from  North  Carolina 26 

VI.    A,  Quartz   crystals    (smoky),   natural   size,   Alexander   County, 

N.  C;  B,  Amethyst  crystals,  Lincoln  County,  N.  C 30 

VII.    A,  Smoky  quartz   crystals   7/16   natural  size,   Hiddenite   P.   0., 
Alexander  County,  N.  C;  B,  Quartz  crystals  with  amethyst 

tips,  natural  size,  Lincoln  County,  N.  C 32 

VIII.  A,  Group  of  quartz  crystals,  parallel  crystallization,  %  natural 
size,  Lincoln  County,  N.  C;  B,  Group  quartz  crystals  en- 
closing clay  and  water,  %  natural  size,  Burke  County,  N.  C.     34 

IX.     Beryl  crystals  from  North  Carolina 38 

X.     Emerald  mine,  Crabtree  Mountain,  Mitchell  County,  N.  C,  about 

25  miles  from  Marion 42 

XL     Beryl  crystals,  natural  size,  Burnsville,  N.  C 44 

XII.    A,  Spodumene  (hiddenite)   in  matrix,  natural  size,  Stony  Point, 

N.  C;  B,  Cyanite,  natural  size,  Burnsville,  N.  C 48 

XIII.  Garnet  and  cyanite  gems  from  North  Carolina 50 

XIV.  A,  Rutile  crystals,  natural  size,  Stony  Point,  N.  C.;.  B,  Rutile, 

reticulated,  natural   size,  near  Hiddenite   P.    0.,   Alexander 

County,  N.  C 52 

XV.    A,  Rutile  with  dolomite  and  muscovite;  B,  Rutile  group,  natural 

size,  Stony  Point,  N.  C 56 


> 


PREFACE 


The  preparation  of  the  report  on  the  History  of  the  Gems  Found  in 
North  Carolina  was  turned  over  to  Dr.  George  Frederick  Kunz  of  New 
York  as  the  recognized  authority  on  gems.  He  has  had  access  to  all  the 
information  relating  to  gems  and  gem  minerals  on  file  in  the  office  of  the 
Survey,  and  has  also  drawn  freely  from  the  various  publications  by 
himself  and  others  relating  to  the  gems  of  the  State.  In  his  introduction, 
Dr.  Kunz  calls  attention  to  the  fact  that  the  production  of  gems  in  the 
State  has  been  largely  incidental  to  the  mining  and  production  of  some 
other  mineral  and  that  there  have  been  but  few  localities  that  have  been 
developed  solely  for  gems.  At  the  present  time,  however,  there  are 
several  companies  operating  in  North  Carolina  simply  for  gem  minerals, 
the  two  more  important  companies  being  the  United  States  Ruby  Com- 
pany and  the  American  Gem  and  Pearl  Company. 

The  report  is  freely  illustrated  and  many  of  the  colored  illustrations 
are  of  gems  in  the  Morgan-Tiffany  and  Morgan-Bement  collections  at 
the  American  Museum  of  Natural  History  of  New  York  City. 

Chapter  I  gives  a  brief  historical  sketch  of  gem  mining  in  the  State, 
but  detailed  accounts  are  given  in  many  instances  under  the  head  of  the 
individual  mineral. 

The  various  gem  minerals  are  described  in  the  next  five  chapters.  The 
localities  are  also  given  and  reference  is  made  to  the  commercial  value  of 
the  gem  material  found. 

This  report  does  not  pretend  to  take  up  a  detailed  account  of  the 
geological  occurrences  of  the  gem  minerals,  or  a  study  of  their  chemical 
and  physical  characteristics,  as  these  will  be  discussed  in  a  later  publi- 
cation. It  has  been  published  especially  for  distribution  at  the  James- 
town Exposition. 

Joseph  Hyde  Pratt, 

State  Geologist. 


> 


INTRODUCTION 


North  Carolina,  with  its  magnificent  mountains  and  its  swiftly  running 
rivers  and  streams,  has  now  for  some  years  come  to  possess  almost  as 
great  a  charm  for  the  Northern  as  it  long  before  had  for  the  Southern 
tourist.  "  The  land  of  the  Sky "  has  become  a  favorite  resort  for  the 
traveler,  the  invalid,  the  sportsman,  the  lover  of  nature,  and  the  seeker 
for  rest,  from  almost  every  part  of  the  country.  For  the  mineralogist, 
too,  it  has  peculiar  interest,  so  great,  indeed,  that  its  scenic  attractions 
have,  for  such  as  he,  been  almost  overmatched,  not  to  say  overlooked, 
in  the  search  for  the  beautiful  crystals  that  are  found  in  its  mountains, 
and  the  variety  of  rare,  minute,  and  interesting  minerals  that  occur  in 
the  brooks  and  streams  associated  with  gold.  Among  these  crystals  and 
sands  occur  many  minerals  that  have  yielded  true  gems,  and  North 
Carolina  has  hence  become  one  of  the  most  notable  States  for  gem  pro- 
duction in  the  American  Union. 

The  finding  of  these  minerals,  however,  has  been  in  most  cases  a 
secondary  or  incidental  result  in  the  search  for  and  mining  of  substances 
more  immediately  desired  for  practical  use  on  a  larger  scale.  These 
last  have  been  essentially  three,  which  have  developed  in  succession,  and 
mark  several  stages  in  the  mineral  production  of  North  Carolina. 

These  stages  were :  (I)  The  gold-mining,  from  early  in  the  last  century 
to  the  time  of  the  Civil  War;  (II)  the  corundum  and  mica  industry,  for 
the  quarter-century  following  that  great  struggle;  and  (III)  the  devel- 
opment of  the  "  rare  earths,"  and  the  monazite  sands,  in  connection  with 
recent  scientific  discoveries  and  appliances,  within  the  last  10  or  15 
years.  To  these  may  be  added  a  fourth  stage,  viz.,  that  of  systematic 
mining  for  the  gems  themselves  at  various  times,  such  as  for  sapphire 
at  Corundum  Hill;  for  ruby  and  rhodolite  in  the  Cowee  Valley;  for 
beryls  in  Mitchell  County,  and  later,  for  amethyst  at  Tessentee  Creek, 
Macon  County. 

Through  the  gold  belt  of  the  western  Carolinas  and  Georgia,  that 
metal  occurs  widely  distributed,  but  in  very  variable  amounts.  At  certain 
points  mining  has  been  conducted  with  profit,  and  in  some  instances 
nuggets  of  impressive  size  have  been  obtained.  More  or  less  active 
working  has  long  been  done  in  the  North  Carolina  gold  fields,  and  the 


Xll  INTRODUCTION. 

total  product  has  been  very  considerable;  but,  strange  as  it  may  seem, 
many  of  the  discarded  gold-washings  of  a  century  ago  are  now  yielding 
more  to  the  owner  of  the  land  for  the  obscure  and  long  unknown  monazite 
sands  than  for  the  gold  originally  obtained  with  them.  In  regard  to  this 
latest  development,  extended  mining  has  recently  shown  that  the  hillsides, 
from  which  the  monazite  sands  in  the  "  branches  "  and  streams  originally 
came,  contain  an  endless  store  of  these  rare  minerals,  and  that  when  the 
ancient  brook-washings  are  exhausted,  the  hillsides  can  be  resorted  to  for 
a  century  to  come.  It  is  in  the  search  for  this  mineral  that  most  of  the 
small  and  beautiful  garnets,  rutiles,  sapphires,  epidotes,  and  other  gems 
have  lately  been  found. 

Between  the  gold-mining  of  earlier  times  and  the  more  recent  and 
varied  developments,  came  the  terrible  years  of  the  "  war  between  the 
States."  When  that  was  past,  brave  and  patriotic  men  like  the  late 
Gen.  Thomas  L.  Clingman,  afterwards  United  States  Senator,  turned  their 
attention  to  developing  the  natural  resources  of  their  State  and  retrieving 
in  every  way  possible  the  ruin  and  devastation  that  had  swept  over  the 
South.  Then  commenced  a  period  of  exploration  and  discovery  in  the 
mineral  and  gem  treasures  of  North  Carolina  that  has  progressed  and 
expanded  to  a  wonderful  extent.  It  began  with  the  corundum  industry 
and  the  mica  mines.  The  presence  of  the  former  mineral  had  been  known 
for  some  years  before  the  war,  but  it  had  not  been  developed.  The  first 
notice  of  its  occurrence  in  the  State  was  in  1846,  by  Prof.  C.  D.  Smith, 
but  with  no  particulars  as  to  the  locality.  About  1850  General  Clingman 
announced  it  from  Madison  County;  andin  1852,  Prof.  E.  T.  Brumby, 
of  the  College  of  South  Carolina,  collected  and  labelled  specimens  from 
Clubb  Mountain,  in  Lincoln  County,  and  placed  them  in  the  College  cab- 
inet at  Columbia,  S.  C.  In  the  next  year  Professor  Ebenezer  Emmons,  of 
the  University  of  North  Carolina,  in  a  report  on  the  midland  counties  of 
the  State,  mentioned  a  discovery  of  corundum  by  Dr.  C.  L.  Hunter,  in 
Gaston  County.  Little  or  nothing  was  done  in  regard  to  it,  however,  until 
immediately  after  the  war,  in  1865,  when  the  Rev.  C.  D.  Smith,  of  Frank- 
lin, Macon  County,  who  had  been  an  assistant  to  Prof.  Ebenezer  Emmons 
on  the  Geological  Survey  of  the  State,  identified  specimens  that  were 
brought  to  him,  visited  the  spot  whence  they  came,  and  discovered  a 
number  of  important  localities.  In  the  next  5  years  a  great  amount  of 
exploration  was  done,  mines  were  opened,  and  an  important  and  enduring 
industry  was  called  into  being.  Among  those  most  active  in  this  field 
of  study  and  progress,  besides  Mr.  Smith  and  General  Clingman,  were  the 
able  State  Geologist,  Prof.  Washington  C.  Kerr,  the  enthusiastic  and 
indefatigable  collector,  Mr.  J.  Adlai  D.  Stephenson,  of  Statesville,  and 


INTRODUCTION".  Xlll 

Mr.  C.  W.  Jenks,  who  opened  the  Corundum  Hill  mine,  at  Franklin,  N.  C, 
about  1870,  and  was  the  first  to  find  gem  sapphire  in  its  original  matrix. 
During  the  same  period,  numerous  valuable  scientific  reports  and  analyses 
were  prepared  and  published  by  such  authorities  as  Prof.  F.  A.  Genth, 
Dr.  J.  Lawrence  Smith,  and  Dr.  T.  M.  Chatard;  and  the  North  Carolina 
corundum,  its  history,  mineralogy,  and  composition,  was  thus  made  widely 
known. 

Although  the  main  value  of  the  mineral  as  mined  was  for  use  as  an 
abrasive  material,  yet  pieces  were  obtained  that  had  color  and  transparency 
enough  to  rank  them  in  some  cases  as  true  gems  and  largely  as  valuable 
specimens.  Among  the  first  fine  crystals  were  some  obtained  by  Prof. 
C.  U.  Shepard;  one  of  these,  now  in  the  Shepard  collection  at  Amherst 
College,  Mass.,  weighs  over  300  pounds.  Besides  the  collecting  tours  of 
Professor  Shepard,  many  annual  visits  were  made  to  the  corundum  region 
by  Mr.  Norman  Spang,  of  Pittsburg,  Pa.,  a  wealthy  and  noted  collector, 
who  encouraged  exploration,  and  brought  back  with  him  much  of  the 
choicest  of  the  "treasure  trove."  Mr.  W.  E.  Hidden,  of  New  York, 
devoted  a  large  part  of  20  years  to  energetic  and  intelligent  search 
for  minerals  and  gems  with  wonderful  success;  and  recently  the  State 
Geologist,  Dr.  Joseph  H.  Pratt,  and  Prof.  J.  V.  Lewis  have  given  ex- 
tended and  detailed  study  to  the  whole  subject  of  the  various  occurrences 
of  corundum  in  the  State.  All  this  activity  has  not  only  developed  the 
industry  itself,  but  has  led  incidentally  to  other  discoveries.  It  may  be, 
indeed,  that  more  has  been  spent  in  the  search  and  in  attempts  at  mining, 
not  always  judicious,  than  the  product  itself  has  yielded;  but  the  effect 
on  the  development  of  the  State  has  been  immense.  In  the  matter  of 
gems  and  remarkable  specimens,  these  years  of  exploration  have  succes- 
sively brought  to  light  one  and  another  fine  gem,  crystal,  or  rare  mineral, 
to  such  an  extent  that  to-day,  were  the  North  Carolina  specimens  removed 
from  the  great  collections  of  the  world,  a  gap  would  be  left  that  could 
not  be  filled,  in  such  places  as  the  American  Museum  of  Natural  History, 
New  York,  the  British  Museum  of  London,  the  Imperial  Museum  of 
Vienna,  the  U.  S.  National  Museum  at  Washington,  the  Field  Columbian 
Museum  of  Chicago,  the  Musee  de  Historie  Naturelle,  Paris;  and  many 
others,  important  but  less  famous. 

During  the  same  general  period,  the  mining  of  mica  came  to  be  another 
important  industry  in  the  revival  of  the  State,  and  this  also  led  to 
discoveries  of  other  rare  minerals  in  the  search  for  valuable  localities  for 
mica.  One  of  the  most  curious  and  interesting  facts  brought  to  light  in 
this  connection,  was  the  clear  evidence  that  some  of  the  best  mica  mines 
had  been  long  and  extensively  worked  by  ancient  aborigines,  either  Indians 


XIV  INTRODUCTION. 

or  earlier  "mound-builders"  (if  these  indeed  be  distinct  peoples),  or 
both.  Ornaments  cut  from  mica,  as  also  shells  and  quartz  crystals,  are 
not  uncommon  in  the  burial-mounds  of  the  Mississippi  valley;  and,  as 
no  mica  occurs  in  that  part  of  the  country,  it  is  clear  that  the  old  excava- 
tions, rudely  made  with  stone  tools,  along  the  outcrops  of  large  mica  veins 
in  Forth  Carolina,  were  the  source  of  this  material,  which  was  evidently 
prized  by  the  prehistoric  tribes  and  widely  distributed  among  them. 

It  is  a  "  far  cry "  from  prehistoric  mounds  and  ancient  and  long- 
forgotten  mica  mines  to  the  incandescent  lighting  of  our  present  civiliza- 
tion and  the  properties  of  rare  chemical  elements.  But  such  are  some 
of  the  contrasts  that  present  themselves  in  speaking  of  North  Carolina 
minerals.  It  is  now  some  18  years  since  the  introduction  of  the 
Welsbach  incandescent  burner,  or  rather  mantle,  that  has  so  improved 
our  gas  illumination.  Instead  of  using  the  light  produced  by  white  hot 
carbon  particles,  as  in  ordinary  flame,  a  hood  or  mantle  is  employed, 
which,  when  heated  by  the  burning  gas,  glows  with  far  greater  intensity7. 
This  mantle  consists  of  a  loosely  woven  fabric  impregnated  with  certain 
compounds  of  rare  elements.  The  first  forms  of  it  employed  zirconia  salts ; 
and  this  fact  led  to  active  mining  of  the  small,  opaque,  and  previously 
unimportant  zircon  crystals  that  are  abundant  at  several  points  in  North 
Carolina.  Since  then  it  has  been  found  that  even  greater  brilliancy  is 
obtained  by  the  use  of  nitrate  of  thorium.  This  latter  is  a  rare  metal, 
found  in  very  few  minerals  and  in  small  amounts;  but  it  is  notably 
present  in  monazite,  a  phosphate  of  this  and  other  oxides  of  rare  elements. 
Monazite  was  formerly  regarded  as  a  very  uncommon  mineral,  but  it  has 
been  found  to  occur  quite  abundantly  in  the  sands  of  the  stream-beds  in 
the  South  Mountain  region,  comprising  several  counties  of  North  Carolina, 
being  derived  from  the  disintegration  of  the  country  rock.  Thus  the 
monazite  industry  has  now  become  highly  important,*  and  it  is  likely  to 
continue  and  increase;  as  the  demand  for  thorium  salts  for  incandescent 
burners  is  very  great.  This  latest  stage  of  North  Carolina  mining — the 
search  for  the  "  rare  earths,"  so-called — has  developed  extensively  within 
a  few  years;  though  General  Clingman  was  active  in  the  earlier  stages 
of  it,  in  promoting  the  zircon  mining,  and  Mr.  W.  E.  Hidden  first  brought 
into  use  the  monazite  sands,  and  induced  the  Welsbach  Company  to 
experiment  with  them  in  1884.  In  1901  the  monazite  output  of  North 
Carolina  was  748,000  pounds,  valued  at  some  $50,000.  Only  Brazil 
surpasses,  or  even  approaches,  this  production.  In  1906  the  output  was 
697,275  pounds,  valued  at  $125,510.  A  total  of  8,426,004  pounds  valued 
at  $635,568,  was  mined  in  the  14  years  1893  to  1906,  inclusive. 

With  these  general  historical  outlines  in  mind,  we  may  pass  to  a  more 


INTRODUCTION.  XV 

special  account  of  North  Carolina  gems,  that  have  been  found,  as  above 
noted,  chiefly  as  incidents  in  the  course  of  mining  enterprises. 

The  diamonds  of  North  Carolina,  although  small  in  size  and  few  in 
number,  are  undoubtedly  authentic.  The  localities  have  been  visited 
and  the  discoveries  verified  by  good  mineralogists.  Whether  their  occur- 
rence will  always  be  as  sporadic  as  these,  or  whether  others  will  be  found, 
time  only  can  tell.  Eubies,  as  fine  in  color  as  those  of  Burma,  but  gener- 
ally small  or  containing  imperfections,  have  lately  been  found  in  the 
Cowee  Valley,  in  Macon  County;  considerable  mining  for  them  has  been 
done,  but  the  financial  outcome  is  still  somewhat  problematical.  Eme- 
ralds, remarkable  as  crystals,  but  rarely  transparent  enough  for  gems, 
were  obtained  in  Alexander  County,  some  years  ago ;  but  a  greater  quan- 
tity has  been  sold  from  the  more  recent  Crabtree  Mountain  discovery,  in 
Mitchell  County,  where  the  emerald  is  translucent  to  transparent,  in  a 
white  granitic  rock,  and  the  whole  is  cut  together  as  a  matrix  material — 
the  quartz  and  feldspar  contrasting  charmingly  with  the  emerald  green. 
Aquamarines,  which  for  beauty  of  colors  have  never  been  rivalled  in  any 
country  of  the  world,  have  been  found  in  some  profusion,  and  many  gems 
have  been  cut  weighing  from  1  to  30  carats,  of  the  most  beautiful  sea- 
blue  color.  Beryls,  both  sea-green  and  yellow,  than  which  none  richer 
have  ever  been  found,  are  also  obtained  in  Mitchell  County  and  elsewhere. 
Mention  should  also  be  made  of  the  peculiar  "lithia  emerald,"  or  hid- 
denite,  found  with  the  large  emerald  crystals  above  noted,  at  Stony  Point, 
Alexander  County.  This  gem-stone  was  discovered  in  1879  by  J.  Adlai  D. 
Stephenson,  then  sent  by  William  E.  Hidden  to  Dr.  J.  Lawrence  Smith 
of  Louisville,  who  named  it  hiddenite.  The  garnets  of  the  gold  washings 
are  well  known;  but  it  remained  for  the  Cowee  Valley  to  produce  a  new 
variety  of  garnet  which  has  received  a  distinct  name,  rhodolite,  and  has 
brought  of  late  greater  financial  returns,  probably,  than  any  other  North 
Carolina  gem.  The  amethysts  from  various  localities  equal  those  found 
in  any  country  of  the  globe;  while  smoky  quartz,  wonderful  as  crystals, 
that  have  commanded  the  attention  and  study  of  some  of  the  greatest 
living  crystallographers,  has  been  obtained  in  Alexander  and  adjoining 
counties.  These  specimens  have  frequently  been  fine  enough  to  cut  into 
gems.  But  quartz  in  its  choicest  form, — rock  crystal — has  been  found  in 
Ashe  County  in  such  magnificent  masses  that  one  of  the  finest  art  objects 
shown  at  the  Paris  Exposition  of  1900,  was  made  from  rock  crystal  ob- 
tained in  this  county  in  1888  by  the  author  as  was  the  cover  of  the 
"  Adams  gold  vase  "  presented  to  the  same  museum.  These  now  form 
parts  of  the  Matthiessen  gift  and  Edward  D.  Adams  gift  to  the  Metro- 
politan Museum  of  Art,  in  New  York,  where  they  are  two  of  the  finest 
objects  in  the  entire  museum. 


XVI  INTRODUCTION. 

It  is  intended  in  this  report  to  illustrate  some  of  the  principal  North 
Carolina  gems,  more  remarkable  usually  as  crystals  than  as  precious  stones 
for  jewelry,  that  grace  the  great  collections  before  alluded  to.  All  those 
shown  on  the  colored  plates,  and  many  of  the  others,  are  contained  especi- 
ally in  the  Morgan-Tiffany  collections,  presented  by  the  munificence  of 
Mr.  J.  Pierpont  Morgan  to  the  American  Museum  of  Natural  History, 
at  New  York ;  these  comprise  the  splendid  collections  formed  by  the  author 
for  Tiffany  &  Company,  of  New  York,  of  American  gems  and  precious 
stones  shown  at  the  Paris  Exposition  of  1889,  and  the  still  finer  and  more 
extensive  one  displayed  by  them  at  the  Paris  Exposition  of  1900 ;  also  the 
Tiffany  collection  shown  at  the  Cotton  States  Exposition  at  Atlanta,  in 
1894,  and  presented  to  the  II.  S.  National  Museum  by  Prof.  L.  T. 
Chamberlin. 

Many  of  the  figures  are  loaned  by  the  courtesy  of  the  publishers  of 
"  Gems  and  Precious  Stones  of  North  America,"  and  will  form  part  of 
the  new  edition  of  that  work,  treating  of  the  Morgan-Tiffany  and  Morgan- 
Bement  collections  of  minerals  in  the  American  Museum  of  Natural 
History;  this  latter  made  up  of  the  Spang  collection  and  many  from  the 
Hidden,  Wilcox,  and  other  collections.  It  was  thought  well  to  illustrate 
for  this  report  specimens  in  places  which  are  readily  accessible,  and  no 
collection  on  this  continent  contains  so  many  choice  examples  of  North 
Carolina  gems  as  does  this  one. 

Fuller  discussions  upon  all  these  subjects,  with  geological,  miner al- 
ogical,  chemical,  or  crystallographic  details,  may  be  found  in  the  reports 
issued  by  the  North  Carolina  Geological  Survey,  which  contains  many 
most  valuable  papers  and  monographs  by  such  authorities  as  Kerr,  Shep- 
ard,  Genth,  Chatard,  Hidden,  Lewis,  and  Pratt,  and  in  the  Journal  of  the 
Elisha  Mitchell  Scientific  Society,  published  at  Chapel  Hill ;  also  in  the 
Annual  Eeports  of  the  Department  of  Mining  Statistics  of  the  United 
States  Geological  Survey,  prepared  by  the  author  under  the  directorship 
first  of  Albert  Williams,  Jr.,  and  then  of  Dr.  David  T.  Day,  who  has  done 
everything  to  encourage  and  increase  public  interest  in  the  development 
of  the  precious  stone  and  mineral  resources  of  the  United  States.  Many 
papers  have  likewise  appeared  on  the  same  topics  in  the  American  Journal 
of  Science.  Among  all  these,  much  of  the  literature  of  the  gem  product 
of  the  State  may  be  found.  It  is  the  purpose  of  the  present  report  to 
present  in  a  clear  and  concise  manner  such  facts  as  may  interest  the 
mineralogist,  the  collector,  or  even  the  tourist  who  wishes  to  acquaint 
himself  with  these  "  crystallized  flowers,"  as  the  celebrated  Abbe  Hauy 
called  them,  whose  enduring  beauty  remains  unchanged  by  the  variations 
of  climate  found  upon  our  globe. 


INTRODUCTION.  XV11 

The  mineral  collections  in  the  State  Museum  at  Ealeigh  include  a 
number  of  valuable  and  interesting  collections  of  gems  and  gem  minerals 
prominent  among  which  is  that  of  Mr.  J.  A.  D.  Stephenson,  for  more  than 
30  years  a  resident  of  North  Carolina  and  an  enthusiastic  explorer  of 
its  natural  resources. 

Much  credit  is  also  due  to  the  late  James  D.  Yerrington,  for  many  years 
the  agent  of  the  Henry  D.  Morse  Diamond-Cutting  Company,  who  for 
30  years  carried  on  correspondence  with  North  Carolina,  doing  much  by 
his  kindly  advice  and  care  to  encourage  the  people  to  send  small  gems, 
which  in  many  cases  led  to  valuable  results. 

George  Frederick  Kunz. 


a 
e 

! 
o 

c 

to 

s 

iv 

to 

PC 


A 
/Section  of  a  .Sapphire  crystal, 

banded  blue  and  yellow,  Jenks  Mine,  Macon  County, 
North  Carolina. 


Asteriared  sapphire, 
Jackson  County, 

North  Carolina. 


# 


Ruby, 

J  en  ks  M  me ,    Macon  County , 
North  Carolina 


D 
First  sapphire  found  ii 

Corundum  Hill,  Macon Countv. 
North  Carolina. 
Restored  to  matrix  after  beinq  cut. 


F 

Ruby, 
-     /alley, 


Sapphire.  (Brown. 

Chatoyant, 

McDowell  (  bunty, 

North  Carolina. 


G 
Ruby, 

vee  Valley, 
Macon  CounK    North  . 


Prepared  under**  directions  of  Gt»rj£FKiM 


HISTORY  OF  THE  GEMS  FOUND  IN 
NORTH  CAROLINA. 

By  GEORGE  FREDERICK  KlJNZ,  Ph.  D. 


CHAPTER  I. 

HISTOKICAL  SKETCH  OF  GEM  MINING. 

Gem  mining  in  North  Carolina  had  its  origin;  first,  in  the  finding  of 
rolled  crystals  in  the  gold  washings  in  several  counties,  some  of  them 
of  gem  value,  notably  a  few  diamonds  and  occasionally  a  zircon  or 
epidote;  then  in  the  development  of  the  mica  mines,  some  of  which 
furnished  some  very  beautiful  beryls  and  others,  garnets.  Some  of  the 
garnet  crystals  of  wonderful  color  and  brilliancy  were  frequently  found 
flattened  between  the  plates  of  mica. 

The  first  systematic  mining  for  gems  was  undertaken  by  Mr.  C.  W. 
Jenks,  in  1871,  when  he  opened  the  corundum  mine,  on  Corundum  Hill, 
near  Franklin,  Macon  County.  This  proved  interesting  scientifically,  and 
many  choice  gems  were  obtained ;  and  the  name  of  the  Jenks,  or  Culsagee, 
mine  became  noted.  The  amount  of  gems  found,  however,  did  not  warrant 
permanent  operations  for  gem  corundum  only,  and  after  a  few  years  the 
mine  was  operated  for  corundum  for  abrasive  purposes.  Another  promis- 
ing mine,  opened  soon  afterwards,  was  the  Buck  Creek,  or  Cullakeenee 
mine,  in  Clay  County ;  but  this  has  had  much  the  same  history.  Next 
came  the  mining  for  emeralds  in  Alexander  County,  at  Stony  Point,  where 
crystals  had  been  found  loose  in  the  soil  formed  by  the  disintegration  of 
the  country  rock.  As  this  region  has  never  been  subjected  to  glacial  action, 
as  the  northern  part  of  the  country  has,  anything  found  in  the  soil,  apart 
from  stream-beds,  has  its  origin  presumably  near  the  spot  where  it  is 
met  with.  The  entire  soil  and  upper  portions  of  the  rocks  here  consist  of 
what  Professor  Kerr  called  the  "  frost  drift,"  i.  e.,  the  same  as  the  under- 
lying rock,  but  decayed  and  decomposed  by  frost  and  weathering  in 
general.  Credit  should  be  given  here  to  the  late  Mr.  J.  Adlai  D.  Stephen- 
son, of  Statesville,  who  recognized  these  conditions  and  stimulated  the 
country  people  to  search  the  surface  of  their  fields  for  such  crystals,  of 


2  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

which  he  gathered  a  great  collection,  in  the  hope  of  locating  mines  near 
the  points  where  anything  of  special  interest  was  encountered.  It  was 
thus  that  the  emerald  locality  at  Stony  Point,  which  also  yielded  the 
new  and  remarkable  hiddenite  gems,  was  traced.  Later,  the  beryl  mine 
at  Spruce  Pine,  Mitchell  County  (PI.  II),  was  opened,  and  worked  from 
time  to  time,  affording  beautiful  beryls.  Then  came  the  discovery  of 
true  rubies  near  Franklin,  Macon  County,  which  has  led  to  considerable 
development  and  to  the  finding  of  some  crystals  which  had  gem  value, 
although  never  very  great.  Near  this  place  occurs  also  the  rhodolite — a 
garnet  between  pyrope  and  almandite.  This  has  been  developed  by  two 
companies  with  remarkable  success,  and  apparently  more  gems  in  value 
have  been  sold  from  this  mine  than  from  all  other  sources  in  North 
Carolina  combined.  More  recent  still  is  the  development  of  the  emerald 
matrix  mine  at  Crabtree  Mountain,  near  Bakersville,  in  Mitchell  County. 
Here  the  emerald  occurs  as  small  richly  colored  crystals,  thickly  strewn 
through  a  white  matrix  of  feldspar  and  quartz ;  and  the  whole  rock  is  cut 
and  polished  together,  as  a  green  and  white  ornamental  stone,  which  is 
quite  in  favor.  Amethyst  of  good  quality,  but  not  to  any  great  extent,  has 
been  developed  in  Lincoln  and  Macon  counties. 

Thus  far,  with  the  exception  of  rhodolite  and  beryl,  the  gem  mines  of 
North  Carolina  have  not  proved  remunerative  enough  to  warrant  a 
continued  development,  either  from  absence  of  sufficiently  rich  material 
or  else  from  the  use  of  methods  that  lacked  cohesiveness  to  assure  success. 

A  few  notes  may  be  given  here  as  to  some  of  the  circumstances  con- 
nected with  mining  development  and  the  men  who  were  active  in  it. 
General  Clingman  has  been  referred  to  already;  another  early  and  very 
active  worker  was  Mr.  C.  W.  Jenks,  who  will  be  mentioned  further  in 
relation  to  the  first  corundum  development.  One  of  the  most  energetic 
explorers  and  discoverers  of  North  Carolina  minerals  was  Mr.  J.  A.  D. 
Stephenson,  of  Statesville.  In  1888  he  prepared  for  the  author  a  sum- 
mary of  the  results  which  he  had  attained  in  the  years  following  the  Civil 
War;  and  from  this  little  unpublished  work  the  following  passages  are 
taken,  to  show  the  spirit  and  the  methods  of  his  activity : 

The  Piedmont  region  lying  between  the  Catawba  and  Yadkin  rivers,  is 
remarkable  for  the  number  of  minerals,  both  common  and  rare,  that  are 
found  in  unusually  fine  crystals.  Being  a  native  of  this  section,  and  an 
ardent  admirer  of  all  the  phenomena  and  beauties  of  nature,  these  crystals 
attracted  my  attention  in  early  life,  and  the  collection  and  study  of 
them  ....  convinced  me  that  they  were  of  more  than  usual  interest;  and 
my  early  experience  in  the  placer  gold  mines  of  North  Carolina  familiarized 
me  with  the  occurrence  of  such  rare  materials  as  monazite,  xenotime,  zircon, 
columbite,  etc.,  in  this  region;   and  knowing  that  these  materials  are  found 


N.    C.    GEOLOGICAL    AND    ECONOMIC    SURVEY 


BULLETIN    NO.    12.       PLATE    II 


HISTORICAL    SKETCH    OF    GEM    MINING.  6 

associated  with  precious  stones  in  other  countries,  impressed  me  with  the 
idea  that  by  ...  .  systematic  search,  valuable  gems  would  be  found  here, 
but  want  of  time  and  opportunity  delayed  the  search  until  1874. 

I  selected  this  section  as  the  most  convenient  for  my  work.  But  the  same 
indications  cross  the  State  from  northeast  to  southeast.  In  fact,  to  draw 
a  line  ....  from  Paris,  Maine,  to  Gainesville,  Ga.,  it  is  surprising  to  me 
how  near  it  passes  all  the  gem  localities  east  of  the  Mississippi  River. 

My  plan  ....  was  to  go  among  the  people  of  the  country,  and  endeavor 
to  interest  them  in  collecting  the  different  crystals  found  in  their  respective 
sections;  this  I  found  an  easy  matter,  especially  with  the  children,  as  they 
took  hold  of  the  idea  readily  and  many  of  them  soon  became  familiar  with  the 
work,  and  not  only  did  good  service  in  developing  the  mineral  resources  of 
the  State,  but  many  of  them  have  acquired  a  good  knowledge  of  mineralogy 
and  general  natural  history. 

Mr.  Stephenson's  discoveries  form  almost  the  only  exception  to  the 
general  statement  made  at  the  outset,  that  the  discoveries  of  gems  and 
gem-minerals  in  North  Carolina  arose  incidentally  in  the  search  or  min- 
ing for  gold,  corundum,  mica,  or  the  rare  earths.  Mr.  Stephenson  had 
described  how  he  set  about  the  search  for  gems  directly,  in  the  assurance 
that  they  must  exist  and  could  be  traced  by  sufficient  endeavor.  In  almost 
all  other  cases,  the  discoveries  have  been  made  accidentally  in  the  course 
of  other  mining  operations. 

A  recent  letter  to  the  writer  from  Mr.  D.  A.  Bowman,  of  Bakersville, 
for  example,  states  the  usual  facts  as  follows : 

As  to  the  discovery  of  beryl,  and  other  gems,  this  was  invariably  by  mica 
mining,  for  outside  of  a  mica  vein,  I  have  never  known  a  beryl  to  be  found. 
In  working  for  black  mica,  the  beautiful  beryl  at  Buchanan  Mine  was  found. 
It  was  the  same  at  Grassy  Creek,  where  Wiseman  and  McKinney  found  the 
deep  green  aquamarines,  and  then  sold  to  the  "  American  Gem  Company." 

I  identified  the  beryl  found  by  Wiseman  and  McKinney  and  shipped  it  to 
Tiffany  &  Company. 

It  was  Mr.  Rorison  and  myself  that  first  discovered  the  emerald  matrix 

at   Brush   Creek  Mountain,    in   1894   or   1895 For   35  years    I    have 

worked  hard  to  bring  to  light  the  various  minerals  and  gems,  and  through 
your  kind  assistance  I  feel  I  have  not  worked  in  vain,  and  have  been  of 
some  little  service  to  my  country. 

In  the  same  letter,  Mr.  Bowman  gives  an  interesting  account  of  the 
first  opening  of  a  mica  mine,  shortly  before  the  war.  In  1858,  General 
Clingman,  while  traveling  in  the  western  part  of  the  State,  stopped  over 
night  with  a  Mr.  Silver,  near  Bakersville,  and  was  interested  to  find 
a  window  filled  with  8  by  10  inch  panes  cut  from  sheets  of  mica,  or  as  it 
was  generally  called,  isinglass.  The  very  next  day,  having  been  shown 
the  spot  where  this  novel  material  was  found,  General  Clingman  hired 
workmen  and  began  sinking  a  shaft.    Mica  was  taken  out  in  magnificent 


4  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

blocks;  but  General  Clingman  was  more  interested  in  a  brilliant  pyrites 
in  the  adjacent  feldspar,  under  the  impression  that  it  was  a  silver  ore. 
After  the  war  had  closed,  in  1869,  the  old  mine,  long  known  in  the 
vicinity  as  the  "  Sink-hole,"  was  brought  to  the  notice  of  a  stove  company 
in  Knoxville,  Tenn.,  who  began  to  operate  it  for  the  mica,  with  great 
success.  Another  mica  mine  in  the  same  section,  the  "  Cloudland,"  was 
discovered  accidentally  at  about  the  same  time,  and  proved  to  be  also 
valuable.  Quite  a  local  excitement  sprang  up,  and  much  prospecting 
was  done  for  mica,  with  the  result  that  several  important  mines  were 
discovered.  One  of  these,  the  "  Clarissa/'  has  yielded  as  much  as  half  a 
million  of  dollars,  by  Mr.  Bowman's  estimate.  It  has  been  worked  down 
to  400  feet,  and  is  now  stopped  by  water;  but  only  awaits  improved 
machinery  and  a  rise  in  the  price  of  mica,  to  be  reopened  with  profit. 

With  all  that  has  been  discovered,  however,  and  all  that  has  been  done, 
in  North  Carolina  gems,  there  are  evidently  much  greater  possibilities 
in  the  future.  One  suggestion  of  a  practical  kind  may  be  made  in 
closing  this  introductory  chapter. 

A  wonderful  development  has  gone  on  in  North  Carolina  in  the  direc- 
tion of  the  great  hotels  at  Asheville  and  Toxaway  and  the  mountain  re- 
sorts at  Linville,  Cranberry  and  elsewhere,  and  a  large  tourist  class  visit 
this  region  every  year.  If  some  of  the  native  prospectors  should  use  their 
spare  moments  as  do  those  in  Eussia,  they  would  gather,  mine  and 
then  cut  the  rock  crystals,  smoky  quartz,  and  other  stones  of  the  region, 
shaping  them  into  ornamental  forms,  as  the  inhabitants  of  the  Ural 
Mountains  have  done  since  the  eighteenth  century,  when  Catherine  the 
Second  sent  two  Italian  lapidaries  to  educate  them  in  the  art.  This  might 
well  prove  a  source  of  interest  and  profit  to  the  people  of  the  State. 


CHAPTER  II. 

DIAMOND 

The  mining  of  gems  in  this  State  had  its  origin  in  the  finding  of  rolled 
crystals  of  gem  value  in  the  gold  washings.  In  these  regions  have  been 
found  crystals  of  diamond,  either  loose  in  the  soil,  or  taken  from  the 
washings  of  auriferous  gravel.1  The  portion  of  the  State  which  has 
yielded  these  valuable  substances  is  that  known  as  the  Piedmont  region — 
a  broad  belt  of  country,  as  its  name  indicates,  at  the  foot  of  the  mountains, 
along  the  eastern  base  of  the  Blue  Eidge.  The  rocks  here  are  meta- 
morphic  and  crystalline,  with  some  Cambrian  beds  a  little  farther  west. 
There  runs  throughout  much  of  this  region  a  belt  or  belts  of  itacolumite, 
the  so-called  "  flexible  sandstone,"  which  is  also  found  in  Brazil  and  in 
the  Ural  Mountains,  and  has  frequently  been  supposed  to  be  the  matrix 
of  diamond  crystals.  The  presence  of  this  peculiar  rock  and  the  occasional 
discovery  of  diamonds  in  adjacent  districts  have  led  to  the  idea  that  the 
itacolumite  belt  of  North  Carolina  might  prove  to  be  a  valuable  diamanti- 
f erous  region ;  but  as  yet  no  diamonds  have  actually  been  discovered  there, 
and  but  few  have  been  found  in  the  loose  debris  of  the  crystalline  beds. 
The  late  Prof.  Frederick  A.  Genth,  of  the  University  of  Pennsylvania, 
described2  the  occurrence  of  the  2  crystalline  varieties  of  carbon  in  that 
State, — the  graphite  in  beds  interstratified  with  schist  or  gneiss;  the 
diamond  in  the  debris  of  such  rocks,  associated  with  gold,  zircon,  garnet, 
monazite,  and  other  minerals,  and  after  speaking  of  this  occurrence  in 
connection  with  rocks  of  identical  age,  as  a  very  interesting  circumstance, 
he  says :  "  The  diamond  has  not  been  observed  in  North  Carolina  in  any 
more  recent  strata,  and  in  the  itacolumite  regions  no  diamonds  have 
ever  been  found,  as  in  Brazil ;  from  which  it  appears  that  the  itacolumite 
of  Brazil  is  either  simply  a  quartzose  mica  slate  of  similar  age  with  the 
North  Carolina  gneissoid  rocks,  or,  if  it  be  contemporary  with  the 
North  Carolina  itacolumite,  the  diamonds  were  not  produced  in  the  same, 
but  came  from  the  older  rocks  and  were  redeposited  with  the  sands 
resulting  from  the  reduction  to  powder  of  these,  and  are  now  found 
imbedded  in  the  same,  their  hardness  having  prevented  their  destruction. 
Seven  or  8  diamonds  have  thus  been  found.     They  occur  distributed 

1  Gems  and  Gem  Mining  in  the  South,  hy  Joseph  Hyde  Pratt ;  The  Southland,  Vol.  I, 
No.  2,  p.  4,  1901. 

2  Mineral  Resources  of  North  Carolina,  p.  28,  Philadelphia,  1871. 


0  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

over  a  wide  area  of  surface  in  the  counties  of  Burke,  Kutherf ord,  Lincoln. 
Mecklenburg,  and  Franklin,  and  I  have  no  doubt  if  a  regular  search  were 
to  be  made  for  them,  they  would  be  more  frequently  found."  To  the 
counties  named  by  Professor  Genth,  must  now  be  added  McDowell,  and 
these  all  form,  with  the  exception  of  Franklin,  a  group  lying  together  in 
the  line  of  the  general  drainage  of  the  country,  southeast  of  the  Blue 
Eidge.  Franklin  County  is  far  to  the  northeast  of  the  others;  and  any 
diamonds  occurring  there  must  be  derived  from  the  disintegration  of 
another  belt  of  crystalline  rocks,  that  traverses  the  eastern  portion  of  the 
State,  near  Weldon,  in  Halifax  County,  or  else  have  been  transported  for 
a  long  distance  by  streams. 

Up  to  the  present  time  there  are  about  ten  authentic  occurrences  of 
diamonds  in  North  Carolina,  besides  several  reported  discoveries  that  are 
not  entirely  reliable.3  One  such  instance  was  that  of  a  quartz  crystal 
found  near  Danbury,  which  was  examined,  and  pronounced  a  (genuine) 
diamond,  by  the  local  jewelers,  who  valued  it  erroneously  at  some 
thousands  of  dollars. 

The  first  specimen  in  order  of  time,  was  found  in  1843,  by  Dr.  F.  M. 
Stephenson,  at  the  ford  of  Brindletown  Creek,  in  Burke  County.  It 
was  an  octahedral  crystal,  and  was  valued  at  $100 ;  but  no  particulars  of 
it  are  on  record.  Another  was  found  in  the  same  neighborhood  by  Prof. 
George  W.  Featherstonhaugh,  but  there  seems  to  be  no  account  of  its 
characters  preserved.  In  1845,  a  diamond  of  1J  carats,  a  distorted  octa- 
hedron with  curved  faces,  clear  and  flawless,  though  tinged  with  yellow, 
was  found  in  the  gold  washings  of  J.  D.  Twitty's  mine,  in  Rutherford 
County.  It  became  the  property  of  the  late  General  T.  L.  Clingman,  of 
Asheville,  who  for  many  years  took  great  interest  and  did  great  service 
in  developing  the  mineral  resources  of  North  Carolina.  This  stone  was 
described  by  Prof.  Charles  U.  Shepard,4  who  announced  the  existence 
of  itacolumite  in  the  gold-bearing  region  of  North  Carolina,  at  the 
meeting  of  the  American  Association  of  Geologists  and  Naturalists  in 
1845,  and  under  the  impression  that  the  itacolumite  is  their  matrix,  had 
predicted  the  further  discovery  of  diamonds  in  that  region,  as  in  Brazil. 
For  this  reason  diamonds,  when  found,  were  naturally  submitted  to  him. 
C.  Leventhorpe,  of  Patterson,  Caldwell  County,  N.  C,  reports  a  small 
and  poor  specimen  found  in  a  placer  mine  on  his  property  in  Eutherford 
County,  and  states  that  he  presented  it  to  Prof.  Shepard,  who  retained  it 
in  his  cabinet.    The  next  important  diamond  was  found  in  gold-washings 

3  Sketch  of  N.  C,  issued  by  the  Dept.  of  Agriculture.  Raleigh,  to  accompany  the  State 
Exhibit  at  the  Charleston  Exposition,  1902.     Diamond,  pp.  40,  41. 

4  Am.  Jour.   Sci.,  Vol.  II,  p.  253,  Sept.,  1846. 


DIAMOND.  7 

in  1852,  by  Dr.  C.  L.  Hunter,  near  Cottage  Home,  Lincoln  County.  It 
is  described  as  an  elongated  octahedron  of  a  delicate  greenish  tint,  trans- 
parent, and  about  half  a  carat  in  weight.  Another,  said  to  be  a  very 
handsome  white  crystal  of  1  carat,  was  obtained  in  the  same  year,  at 
Todd's  Branch,  Mecklenburg  County;  it  became  the  property  of  the  late 
Dr.  Andrews,  of  Charlotte,  N.  C,  who  also  informed  Prof.  G-enth  that  a 
beautiful  black  stone  "  as  large  as  a  chinquapin  "  was  afterwards  found 
by  some  gold-washers  in  the  same  locality.  This  specimen,  unfortunately, 
was  crushed  with  a  hammer,  sharing  the  fate  of  several  American 
diamonds  when  submitted  to  the  mistaken  test  which  confounds  hardness 
with  strength.  The  fragments  of  the  black  diamond  scratched  corundum 
with  ease,  thereby  proving  its  genuineness.5  Soon  after  this  two  dia- 
monds, one  a  beautiful  octahedron,  were  reported  by  Prof.  F.  A.  Genth, 
as  obtained  at  the  Portis  mine,  in  Franklin  County.  This  locality  is  far 
removed  from  the  others  in  North  Carolina, — a  point  which  is  referred  to 
presently. 

Two  discoveries  are  recorded  in  McDowell  County,  one  of  two  or  three 
small  crystals  found  at  the  headwaters  of  Muddy  Creek,  and  the  other 
a  fine  stone  picked  up  at  a  spring  near  Dysartville,  in  1886.6  This  was  a 
distorted  and  twinned  hexoctahedron,  of  4-J  carats,  transparent,  with  a 
grayish-green  tint.  The  little  son  of  Mr.  Grayson  Christie,  going  for 
water  to  a  spring  on  the  farm  of  Alfred  Bright,  observed  this  peculiar 
shining  pebble,  and  brought  it  home.  After  some  local  interest  had 
developed,  its  nature  was  suspected,  and  it  was  sent  to  New  York  and 
there  at  once  identified.  A  model  of  it  was  exhibited  at  the  Paris  Ex- 
position of  1889,  and  is  now  in  the  Tiffany-Morgan  collection  of  the 
American  Museum  of  Natural  History.  The  present  writer  subsequently 
visited  the  spot,  and  fully  authenticated  all  the  facts  of  the  discovery. 
The  sediment  in  the  bed  of  the  spring  was  taken  out  and  examined,  and 
also  the  small  hollows  on  the  adjacent  hillside.  None  of  the  ordinary 
associations  of  the  diamond  were  observed,  and  hence  it  is  probable  thai 
the  crystal  was  washed  down  with  decomposing  rock-soil  from  higher 
ground,  perhaps  during  some  freshet ;  or  possibly  it  may  have  been  carried 
to  the  spring  by  miners,  and  left  unobserved  or  unrecognized  among  the 
"  wash-up "  of  the  gold-bearing  sand  from  some  neighboring  placer. 
There  are  gold  mines  in  McDowell  County,  worked  chiefly  by  hydraulic 
sluicing,  but  as  a  rule  the  stones  that  remain  in  the  sluices  are  carefully 
examined,  as  the  miners  know  that  gems  are  sometimes  thus  found. 
The  value  of  the  Dysartville  diamond  as  a  jewel  will  hardly  represent  the 

3  Handbook  of  North  Carolina,  Raleigh,  1886,  pp.  197,  198. 
6  Am.  Jour.  Sci.,  Vol.  XXXIV,  Dec,  1887,  p.  490. 


8  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

interest  that  attaches  to  it  as  a  local  specimen  of  large  size  and  fine 
appearance.      (See  Plate  III.) 

Another  diamond  is  reported  to  have  been  found  9  years  before,  in  18?  7, 
by  a  small  boy,  in  the  same  region  as  the  last.  It  weighed  2f  carats, 
and  is  described  as  white  and  lustrous,  but  somewhat  flawed,  and  of 
irregular  flattened  form,  resembling  a  bean,  with  the  crystal  faces 
obscure.  The  finder  sold  it  in  Marion  for  a  mere  nominal  sum.  Mr. 
B.  B.  Price,  of  Marion,  put  it  for  disposal  into  the  hands  of  Mr.  James 
M.  Gere,  of  Spruce  Pine,  an  extensive  buyer  and  miner  of  North  Carolina 
mica.  He  took  it  to  Syracuse,  N.  Y.,  and  sold  it  there  to  Messrs.  C.  M. 
Ball  &  Co.,  jewelers,  for  the  sum  of  $18.  It  was  finally  sent  to  New 
York,  where  it  was  cut  into  a  small  gem  and  its  identity  lost.7 

Still  another  crystal  is  in  the  State  Museum  at  Ealeigh.  The  partic- 
ulars of  its  discovery  are  not  known;  but  it  was  purchased  by  the  State 
with  the  collection  of  the  late  Dr.  J.  A.  D.  Stephenson,  of  Statesville, 
N".  C,  who  had  possessed  it  for  some  years,  and  reported  that  he  had 
bought  it,  with  other  minerals,  from  a  countryman  in  Burke  County. 
It  has  an  oblong  spheroidal  form,  the  faces  being  curved  and  rounded; 
and  it  weighs  5/16  of  a  carat.  These  particulars  are  given  in  a  recent 
letter  from  Mr.  T.  K.  Brunner,  Secretary  of  the  State  Department  of 
Agriculture  at  Ealeigh. 

The  latest  well  established  discovery  was  in  1893,  in  Cleveland  County, 
near  King's  Mountain.  It  was  a  polished  octahedron,  weighing  J  carat, 
of  a  bright  light  canary  yellow. 

It  will  be  noticed  that  most  of  these  localities  are  situated  in  the 
same  section  of  the  State, — in  the  mountainous  district,  lying  just 
north  from  the  northernmost  extension  of  the  border  of  South  Carolina. 
Here  the  counties  of  Burke,  Eutherford,  McDowell,  and  Cleveland  lie 
closely  adjacent,  and  Mecklenburg  only  a  short  distance  eastward. 

The  foregoing  list  includes  all  the  authentic  diamonds  thus  far 
discovered  in  North  Carolina.  A  number  of  small  stones,  exhibited  as 
diamonds,  have  been  found  at  Brackettstown.  They  are  similar  to 
supposed  diamonds  found  by  J.  C.  Mills  at  his  mine  at  Brindletown,  but 
these  were  transparent  zircon  or  smoky-colored  quartz,  the  former  of 
which  has  a  lustre  readily  mistaken  by  an  inexperienced  person  for  that 
of  a  diamond.  A  number  of  pieces  of  rough  diamond,  exhibited  as 
from  the  same  section,  have  been  decided  to  be  of  South  African,  not 
Carolinian  origin.     It  is  to  be  hoped  that  the  few  legitimate  discoveries 

7  Addendum  to  the  "  Minerals  and  Mineral  Localities  of  North  Carolina,"  by  William 
Earl  Hidden,  p.  2,  1889  ;  Reprinted  from  Jour,  of  the  Elisha  Mitchell  Scientific  Society, 
6th  year,  part  II.     Raleigh,  1890. 


Plate  No  HI 


IV         G 

Diamond, 
Dysortvi 

McDowell  County. 

North  Carolina. 


Alexander  County 
Ncrih  Carolina. 


Aquamarine, ( Blue 

Spruce  Pine, 
Mitchell  (buniy, 
North  Carolina. 


Beryl  Cats  Eye 

Spruce  Pine, 
Mitchell  County, 

North  Carolina. 


Aquamarine, 

(.Sea  Green. ) 
Spruce  Pine, 
Mitchell  County, 
North  Carolina. 


F 
Hiddenite. 

Stony  Point, 
AlexanderCounr 

North  Carolina. 


Emerald  Matrix 

'  !rabtroc  Mounl 

Mitchell  Co>... 
North  Carolina. 


1  iili  byUshei  I'm  no  A; 


■      I 


DIAMOND.  'J 

actually  made  in  this  locality  will  not  lead  to  deceptions,  which  would 
greatly  retard  any  natural  development  of  interest.  It  is  quite  possible 
that  diamonds  may  be  found  widely  distributed  throughout  the  auriferous 
belt  of  the  Carolinas  and  northern  Georgia;  and  that,  in  the  often  rude 
and  hurried  methods  of  gold-washing  employed,  they  may  have  been 
overlooked  in  the  past,  and  now  lie  buried  in  the  piles  of  sand  that 
stretch  for  miles  along  the  water-courses.8  It  is  stated  that  3  diamond 
crystals  were  obtained  many  years  ago  on  Koko  Creek,  at  the  headwaters 
of  the  Tellico  Eiver,  in  East  Tennessee,  on  the  "  Bench  lands  "  of  the 
Smoky  or  Unaka  Mountains.  If  this  statement  be  correct,  it  probably 
points  to  a  western  extension  of  the  diamond  belt  of  North  Carolina,  or 
to  the  transportation  of  the  stones  thence  by  streams.9 

Franklin  'County  is  far  removed,  both  geographically  and  geologically, 
from  all  the  other  points  above  noted;  and  indeed  in  both  aspects,  a 
possible  relation  is  suggested  rather  with  the  celebrated  Manchester,  Vir- 
ginia, diamond.  In  both  these  cases,  if  the  diamonds  came  from  the 
Blue  Eidge,  they  must  have  been  carried  a  long  distance  by  streams.  There 
is,  however,  a  possible  nearer  source,  in  the  belt  of  "  Atlantic  "  or  "  Tide- 
water "  gneiss,  which  runs  down  from  New  York  to  and  through  the 
Carolinas,  forms  the  rapids  in  the  James  at  Richmond,  and  goes  on 
directly  toward  Franklin  County,  North  Carolina.  This  is  merely  a 
suggestion,  however,  caused  by  the  geographical  isolation  of  these  two 
occurrences;  nowhere  else  along  this  gneissic  belt  have  diamonds  ever 
been  found. 

8  Gems  and  Precious  Stones  of  North  America,  by  Geo.  F.  Kunz,  New  York,  1890,  p. 
21.     8vo,  363  pp. 
M.  o...  p.  35. 


CHAPTER  III. 
COKUKDTTM  GEMS.1 

While  diamonds  and  gold  are  found  in  the  Piedmont  country  east  of 
the  mountains,  North  Carolina's  chief  corundum  rocks  are  in  Madison, 
Buncombe,  Haywood,  Jackson,  Macon,  and  Clay  counties,  where  numer- 
ous occurrences  are  known.  A  second  and  a  third  line  of  localities  are 
recognized,  but  they  are  of  slight  importance.  There  are  occurrences  of 
corundum,  however,  east  of  the  mountains,  in  the  counties  of  Gaston, 
Lincoln,  Burke,  Iredell,  Guilford,  and  Forsyth.  The  late  Prof.  John  A. 
Humphreys  called  attention  to  some  of  these  in  18 — ,  in  his  paper  No.  12 
of  "  Natural  History  Notes  on  Western  North  Carolina,"  and  suggested 
their  possible  importance  in  comparison  with  those  farther  west.  Some 
of  the  earliest  specimens,  also,  were  collected  in  Gaston  and  Lincoln 
counties,  as  will  be  noted  further  on.  But  the  main  corundum  region  is 
beyond  the  Blue  Eidge,  where  it  forms  a  belt  or  zone  of  large  extent, 
stretching  along  the  whole  course  of  the  Southern  Appalachians.  The 
principal  corundum  gems  are  the  ruby,  sapphire,  and  oriental  emerald. 

According  to  Dr.  Thomas  M.  Chatard,2  of  the  United  States  Geological 
Survey,  the  corundum  region  extends  from  the  Virginia  line  through  the 
western  part  of  South  Carolina,  and  across  Georgia  as  far  as  Dudleyville, 
Ala.  Its  greatest  width  is  estimated  to  be  about  100  miles.  This 
belt  has  sometimes  been  called  the  chrysolite  or  chromiferous  series, 
owing  to  the  presene  of  chrysolite  containing  chromite,  from  the  former 
of  which  corundum  was  believed,  by  certain  authorities,  to  have  been 
derived  by  alteration.3  In  this  decomposed  and  altered  chrysolite  (dunite) 
throughout  the  Southern  States,  corundum  is  found  in  place;  and  the 
earlier  writers  on  the  subject,  including  such  eminent  authorities  as  Dr. 
J.  Lawrence  Smith  and  Prof.  Charles  U.  Shepard,4  believed  it  to  be  con- 
fined to  the  serpentinous  rocks  of  this  belt,  which  represent  largely  an  al- 

1  For  more  detailed  descriptions  of  corundum  occurrences  in  North  Carolina,  refer- 
ence is  made  to  Reports,  N.  C.  Geol.  Survey,  Vol.  I,  1905,  on  Corundum  and  the  Basic 
Magnesian  Rocks  of  N.  C,  by  Joseph  Hyde  Pratt  and  Joseph  Volney  Lewis  ;  Corundum 
and  the  Basic  Magnesian  Rocks  of  N.  C,  by  J.  Volney  Lewis,  Bull.  No.  11,  1895  ;  and  also 
Gems  and  Gem  Mining  in  the  South,  by  Joseph  Hyde  Pratt ;  The  Southland,  Vol.  I, 
Nos.  3  and  4,  1901. 

2  Mineral  Resources  of  the  United  States,  p.  714,  1883-1884. 

3  See  Corundum  :  Its  Alterations  and  Associated  Minerals,  by  Frederick  A.  Genth, 
in  Contributions  from  the  Laboratory  of  the  University  of  Pennsylvania,  No.  I,  Phila- 
delphia, 1873. 

4  Corundum  and  its  Gems  :     A  Lecture  before  the  Society  of  Arts,  Boston,  1876. 


CORUNDUM    GEMS.  11 

teration  product  of  chrysolite.  Such  was  the  general  view  during  the 
years  following  the  Civil  War,  when  the  mineral  resources  of  North  Caro- 
lina were  beginning  to  be  actively  developed. 

More  recently,  it  has  come  to  be  seen  that  this  is  only  one  phase  of 
corundum  occurrence,  although  much  the  most  conspicuous.  The  investi- 
gation of  the  Geological  Survey,  conducted  by  Dr.  Joseph  H.  Pratt,0 
and  Prof.  Joseph  Volney  Lewis,6  have  traced  several  distinct  associations 
in  which  corundum  appears.  Three  of  these  are  clearly  developed  in 
North  Carolina: — (1)  In  the  crystalline  schists,  as  long  prismatic  crys- 
tals, usually  opaque,  grey,  pink,  or  blue;  (2)  in  the  decomposed  chrysolite 
or  peridotite  rocks,  called  dunites,  that  intersect  the  schists,  as  igneous 
intrusions;  the  crystals  often  large  and  variously  colored,  but  very  rarely 
of  gem  quality;  (3)  in  more  or  less  decomposed  basic  rocks,  with  garnets, 
in  the  Cowee  Valley  in  Macon  County,  where  the  crystals  are  small,  in 
six-sided  tables  or  to  some  extent  rhombohedral,  sometimes  transparent 
and  rich  red.  These  last  are  the  "  Cowee  rubies."  The  second  group 
corresponds  to  the  chrysolite  or  serpentine  occurrence  noted  by  the 
earlier  writers ;  the  first  has  been  but  recently  distinguished  with  clearness 
from  the  second.  It  appears  now,  through  further  researches  of  Dr.  Pratt 
that  under  this  first  head  are  again  included  two  very  different  modes  of 
geological  occurrence, — one  in  a  hornblende  gneiss  arising  from  the 
alteration  of  an  igneous  rock  and  its  foliation  by  pressure,  and  the  other 
in  a  true  gneiss  varying  to  a  quartz  schist,  which  has  resulted  from  the 
metamorphism  of  sedimentary  strata.  These  latter  gneisses  occur  sepa- 
rately, extending  along  the  crest  of  the  Blue  Kidge,  at  an  elevation  of 
3000  to  4000  feet,  from  Eabun  County,  Georgia,  to  Clay  Count}',  N.  C. 
The  corundum  appears  in  irregular  bands  in  the  gneiss,  evidently 
belonging  to  it,  and  not  in  veins  or  dikes.  Dr.  Pratt  concludes  that  these 
were  originally  aluminous  shales,  and  that  in  the  long  process  of  meta- 
morphism, the  alumina  may  have  first  separated  as  bauxite  (hydra ted 
oxide),  and  subsequently  formed  corundum  bands  parallel  to  the  planes 
of  lamination. 

In  all  the  other  cases,  the  corundum  is  a  product  of  true  igneous  action, 
having  either  crystallized  out  from  a  molten  rock  directly,  or  formed  at 
the  contact  zones  of  such  rock  with  others  which  it  penetrated,  by  mutual 
chemical  actions  under  the  influence  of  great  heat.  The  former  is  a 
frequent  manner  in  which  corundum  exists.  The  extensive  deposits  lately 
made  known  in  Ontario,  are  in  a  nepheline-syenite,  plainly  igneous  in 

5  Amer.  Jour.  Sci.,  Vol.  VI,  Pt.  4,  p.  59,  1898  ;  Vol.  X,  pp.  295-298,  1900. 
0  N.  C.  Geol.  Survey,  Bull.  11,  1896  and  Vol.  I,  1905. 


12  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

origin,  and  the  gem  corundums  of  Montana  are  derived  from  intrusive 
dikes.  The  occurrence  in  crystalline  limestone,  in  northern  New  Jersey, 
like  that  in  Burma,  is  probably  of  the  other  type,  a  result  of  contact 
metamorphism,  although  Messrs.  Brown  and  Judd  have  advanced  a 
theory  for  the  Burman  mines,  that  attributes  even  these  to  an  original 
igneous  source. 

The  whole  question  of  the  geology  of  corundum, — its  origin,  mode  of 
formation,  etc.,  has  been  obscure  and  uncertain  for  a  long  time.  Many 
theories  have  been  advanced,  only  to  be  modified  by  subsequent  dis- 
coveries. Within  a  few  years  past,  however,  important  progress  has  been 
made;  and  though  much  remains  to  be  ascertained,  a  number  of  points 
have  gradually  been  established. 

Among  these  is  the  fact  that  corundum,  long  regarded  as  a  somewhat 
rare  mineral,  is  really  of  more  frequent  occurrence  than  was  formerly 
supposed ;  and  also  that  it  has  been  formed  under  various  conditions  and 
in  several  distinct  ways.  As  already  stated  above,  it  is  now  known  to 
have  been  produced  (1)  by  crystallizing  directly  out  of  igneous  rocks; 
and  (2)  by  various  forms  of  alteration  and  metamorphism,  in  both 
igneous  and  sedimentary  rocks.  The  first  head  is  further  divided  into 
occurrences  in  basic  and  in  acidic  rocks,  and  again  into  cases  when  the 
alumina  was  present  in  excess  in  the  igneous  rock  itself,  as  an  original 
constituent  (autogenic),  and  those  when  it  was  introduced  in  pieces  of  an 
aluminous  shale  traversed  by  the  igneous  rock  and  taken  up  by  it  in  its 
ascent  (allothigenic).  All  these  eases  of  occurrence  have  now  been  fairly 
identified  in  the  corundum  localities  in  the  United  States. 

The  earlier  writers  generally  held  that  pure  alumina  (corundum  )was 
a  secondary  or  derivative  mineral,  formed  by  the  alteration  of  other  species 
in  which  it  had  previously  existed  in  combination,  as  a  silicate.  Its 
close  association  with  the  altered  peridotite  or  chrysolite  (dunite)  belt 
of  the  South  Atlantic  States,  has  already  been  referred  to,  and  the  belief 
of  some  geologists  that  the  corundum  was  derived  from  the  chrysolite,  by 
various  processes  of  alteration.  The  late  eminent  Dr.  F.  A.  Genth,  while 
not  committing  himself  to  any  positive  statement  as  to  the  origin  of  the 
corundum,  developed  a  remarkable  body  of  facts  as  to  the  alteration  of 
corundum  itself  into  various  other  and  associated  minerals.'  There  is  not 
space  here  to  go  into  any  full  outline  of  the  course  of  observation  and 
opinion.  This  has  been  very  well  done  by  Dr.  J.  H.  Pratt,  of  the  North 
Carolina  Geological  Survey,  in  his  recent  paper  "  On  the  Origin  of  the 
Corundum  associated  with  the  Peridotites  in  North  Carolina."  s     In  this 

7  The  Alterations  of  Corundum;  Proc.  Am.  Phil.  Soc,  XIII,  pp.  361-406,  1873. 

8  Am.  Jour.  Sci.,  IV,  Vol.  VI,  No.  31,  July,  1898,  pp.  49-65. 


CORUNDUM   GEMS.  13 

article  he  shows  how  the  igneous  origin  of  these  peridotites  or  dunites  has 
come  to  be  gradually  established,  and  the  separation  of  the  corundum  from 
them  as  an  original  ingredient.  In  a  subsequent  and  more  extended  paper 
on  "  The  Occurrence  and  Distribution  of  the  Corundum  in  the  United 
States," 9  Dr.  Pratt  describes  all  the  known  localities,  and  the  special 
features  of  each. 

A  full  and  excellent  account  of  the  distribution,  the  geology,  and  the 
history  and  literature  of  corundum,  with  special  reference  to  Georgia,  has 
also  been  given  by  Prof.  Francis  P.  King,  assistant  geologist  of  that 
State,  in  his  "  Preliminary  Eeport  on  Corundum  Deposits  in  Georgia."  10 

The  earliest  discovery  of  corundum  in  the  United  States  was  reported  in 
1819,  by  Mr.  John  Dickson,  in  an  article  on  the  mineralogy  and  geology 
of  the  two  Carolinas,  published  in  "  Silliman's  Journal."  u  The  crystals 
which  he  obtained  came  from  Laurens  District,  S.  C,  a  locality  which  has 
since  yielded  a  considerable  amount  of  both  corundum  and  zircon. 

Of  corundum  in  North  Carolina,  the  first  recorded  account  is  the 
statement  by  Prof.  C.  D.  Smith,  who  was  the  assistant  State  Geologist 
under  Professor  Emmons,  that  it  was  found  in  1846,  but  he  does  not 
say  where  or  by  whom.  Dr.  F.  A.  Genth  reports  that  a  large  mass  of 
corundum  was  obtained  in  1847,  in  Madison  (then  a  part  of  Buncombe) 
County,  on  the  French  Broad  Eiver,  3  miles  below  Marshall. 

This  was  a  dark  blue  piece,  associated  with  chlorite  and  margarite. 
In  1849  or  1850,  Prof.  Charles  U.  Shepard  received  from  Gen.  Thomas  L. 
Clingman  several  pounds  of  a  coarse  blue  sapphire  broken  from  a  large 
crystal  "  picked  up  at  the  base  of  a  mountain  on  the  French  Broad 
Eiver  in  Madison  County,  N.  C."  This  is  probably  the  same  discovery  as 
that  previously  noted. 

Whether  the  Indians  knew  anything  of  corundum  is  uncertain.  It  is 
too  hard  for  them  to  have  worked  it  in  any  way,  and  it  has  not  been 
recognized  among  any  of  the  minerals  occasionally  found  in  graves  or 
mounds.  As  Professor  King  of  Georgia  says,  it  is  not  unlikely  that  some 
of  the  pink  or  blue  fragments  of  crystalline  corundum  found  in  the 
gravels  of  the  Southern  States  may  have  been  noticed  and  prized  as 
ornaments;  but  the  aborigines  certainly  made  very  little  use  of  it 
otherwise.  A  curious  fact  is  noted  by  Professor  King,  however,  in  refer- 
ence to  the  corundum  mine  at  Track  Eock,  in  Union  County,  Georgia, — 
that  near  the  locality  is  a  rock  covered  with  curious  carvings,  many  of 
them  resembling   animals   tracks,   whence  the  place   derives   its   name. 

9  U.  S.  Geol.  Survey  Bull.,  No.  180,  93  pp.,  1901,  and  Bull.  269,  175  pp.,  1906. 

10  Geol.  Survey  of  Georgia,  Bull.  No.  2,  133  pp.,  1894. 
"Am.  Jour.  Sci.,  I,  Vol.  Ill,  p.  4. 


14  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

Possibly  the  Indians  may  have  employed  fragments  of  corundum  in 
executing  these  designs  on  the  rock  (?). 

This  first  recognition,  far  to  the  west,  was  soon  followed  by  some  on 
the  eastern  side  of  the  Blue  Eidge.  In  1852,  Prof.  E.  T.  Brumby,  of  the 
College  of  South  Carolina,  collected  specimens  of  corundum  at  Clubb 
(now  Chubb)  Mountain,  in  Gaston  County,  and  placed  them  in  the 
cabinet  of  the  College,  where  they  still  remain,  with  Prof&ssor  Brumby's 
dated  labels.  They  are  rough  crystals  and  crystalline  masses,  of  dark 
blue  color,  covered  with  the  micaceous  alteration-products  so  frequently 
present;  but  they  have  high  interest  in  being  perhaps  the  first  North 
Carolina  specimens  to  be  determined,  labeled,  and  placed  in  a  public 
collection.  About  the  same  time  Dr.  C.  L.  Hunter  discovered  corundum 
in  Gaston  County,  perhaps  at  the  same  locality,  and  Professor  Emmons 
referred  to  it  in  his  report  on  the  midland  counties  of  Xorth  Carolina  in 
1853.12  The  Civil  War  began  soon  after,  putting  a  stop  to  further  research, 
and  it  was  not  until  its  close  that  investigations  were  resumed. 

Eev.  C.  D.  Smith,  of  Franklin,  N".  C,  who  in  his  former  position  on 
the  State  Geological  Survey,  had  become  very  familiar  with  the  minerals 
of  the  State,  now  discovered  most  of  the  important  localities  in  North 
Carolina.  In  1865  a  specimen  was  brought  to  him  from  a  point  west  of 
the  Blue  Eidge,  which  he  recognized  as  corundum ;  he  visited  the  locality, 
collected  specimens,  and  announced  the  occurrence.  This  was  the  origin 
of  the  mining  industry  now  so  valuable.  These  discoveries  led  to  further 
exploration,  and  many  localities  were  found  in  the  same  region,  which 
have  since  been  more  or  less  developed. 

In  1870,  Mr.  Smith  sketched  the  corundum  belt  of  North  Carolina, 
as  running  in  a  southwesterly  course  across  Macon  County,  where  it 
strikes  the  Georgia  State  line,  its  general  direction  coinciding  with  the 
trend  of  the  Blue  Eidge,  until  it  reaches  the  head  of  the  Tennessee  Eiver, 
when  it  suddenly  ceases  on  encountering  the  Nantahala  Mountain  (a 
spur  of  the  Blue  Eidge  here  running  due  north),  to  reappear  10  miles  to 
the  northwest  on  Buck  Creek,  whence  it  pursues  its  original  course  of 
northeast  and  southwest  across  the  Chunkygal  mountains,  where  it  again 
enters  the  Blue  Eidge.  Later  investigation  has  revealed  a  more  extended 
belt. 

Two  of  the  localities  in  this  region  have  been  much  the  more  promi- 
nent,— those  at  Corundum  Hill  and  Buck  Creek. 

With  the  opening  of  the  Culsagee  (Cullasagee,  or  Cullasaja)  mine,  on 
Corundum  Hill,  near  Franklin,  Macon  County,  by  Mr.  C.  W.  Jenks,  in 

12Amer.  Jour.  Sci.,  II,  Vol.  XV,  p.  373,  May,  1853. 


CORUNDUM    GEMS.  15 

1871,  the  first  systematic  attempt  to  mine  gems  within  the  State  was 
begun.  From  a  scientific  point  of  view  the  operations  were  most  interest- 
ing, but  the  number  of  gems  found  did  not  warrant  permanent  operations, 
for  gems  only,  and  after  a  few  years  mining  for  this  mineral  was  for 
abrasive  purposes. 

This  mine,  which  includes  several  openings,  is  situated  on  the  Culsagee 
or  Sugartown  Fork  of  the  Little  Tennessee  Eiver,  8  or  9  miles  above 
(southeast  of)  the  town  of  Franklin,  the  county  seat,  at  an  elevation 
of  about  2500  feet  above  the  sea.  The  Corundum  Hill  is  essentially  an 
outcrop  of  peridotite  (dunite),  some  10  acres  in  area,  and  rising  to  a 
height  of  between  300  and  400  feet.  Most  of  the  openings  are  along  the 
contact  of  the  dunite  with  the  gneiss  or  schist  through  which  it  rises, 
and  follow  "  contact  veins  "  of  corundum.  It  has  often  been  called  the 
Jenks  mine,  also  the  Culsagee  and  the  Corundum  Hill,  names  derived 
from  the  locality  and  from  the  name  of  its  first  operator,  Charles  W. 
Jenks,  of  Boston,  Mass.  It  was  subsequently  worked  by  the  Hampden 
Emery  Company,  of  Chester,  Mass.,  under  the  direction  of  Dr.  S.  F. 
Lucas,  and  became  known  as  the  Lucas  mine.  It  is  now  owned  by  the 
International  Corundum  &  Emery  Co.,  of  New  York,  which  also  controls 
several  other  less  important  mines  in  the  same  neighborhood. 

The  other  prominent  locality  was  the  Buck  Creek  or  Cullakenee  (also 
spelled  Cullakeenee  and  Cullakenish)  mine,  in  Clay  County,  20  miles 
southwest  of  Franklin.  It  was  opened  soon  afterwards,  and  has  had  a 
similar  history.  The  outcrop  is  much  more  extensive,  but  less  work  has 
been  done  there. 

These  mines,  especially  the  first,  have  been  described  in  various  scientific 
papers  and  reports.  One  of  the  earliest  published  accounts  was  given  by 
Prof.  C.  U.  Shepard  13  in  1872 ;  another  was  by  Mr.  Jenks  himself,  2 
years  later,  in  a  paper  read  before  the  Geological  Society  of  London.  In 
1876,  Prof.  Eossiter  W.  Eaymond  read  an  excellent  paper  before  the 
American  Institute  of  Mining  Engineers";  in  1883,  Dr.  Thomas  M. 
Chatard,  of  the  XL  S.  Geological  Survey  described  it  again.18 

Besides  these  valuable  articles,  there  are  the  no  less  excellent  references 
in  various  reports  of  the  State  Survey,  by  Prof.  W.  C.  Kerr,  and  in 
articles  by  Dr.  F.  A.  Genth,  who  was  associated  with  him  in  portions 
of  the  survey  work,  and  by  Dr.  J.  Lawrence  Smith. 

Professor  Shepard  described  the  dunite  rock  very  well,  and  recognized 
it  distinctly  as  an  altered  form  of  chrysolite,  referring  it  to  the  species 

13  Am.  Jour.  Sci.,  II.  Vol.  IV,  Aug.-Sept.,  1872. 

14  Trans.  Am.  Inst.  Min.  Eng.,  Chattanooga  meeting,  May,  1876. 

15  Mineral  Resources  of  the  U.   S.,  1883-1884,  p.  714. 

3 


16  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

known  as  villarsite.  Dr.  Eaymond  fully  perceived  its  character  as  an 
igneous  intrusion,  differing  from  some  other  writers  on  this  point,  since 
clearly  established.  Dr.  Chatard  describes  the  Culsagee  outcrop  as  con- 
sisting of  chrysolite  (dunite)  mingled  with  hornblende.  The  corundum 
is  enclosed  among  various  hydromicaceous  minerals,  commonly  grouped 
under  the  term  chlorite,  between  the  gneiss  and  the  dunite,  from  the 
alteration  of  which  they  have  evidently  been  formed.  It  occurs  chiefly 
in  crystalline  masses,  often  of  considerable  size,  and  sometimes  suitable 
for  gems  (PI.  IV,  A).  At  other  parts  of  the  mine  it  is  found  in  small 
crystals  and  grains  mingled  with  scales  of  chlorite,  forming  what  is  called 
the  "  sand  vein."  This  is  so  loose  and  incoherent  that  it  is  worked  by  the 
hydraulic  process;  and  the  small  size  of  such  corundum  is  the  saving  of 
much  labor  in  the  next  process  of  pulverizing.  At  Buck  Creek  the 
chrysolite  rocks  cover  an  area  of  over  300  acres,  and  from  that  point 
southward  the  hornblende  rocks  assume  greater  proportions,  being  asso- 
ciated with  albite  instead  of  the  ordinary  feldspar  and  forming  an 
albitic  cyanite  rock.  There  is  also  found  here  the  beautiful  green 
smaragdite,  called  by  Professor  Shepard  chrome-arfvedsonite,  which, 
with  red  or  pink  corundum,  forms  a  beautiful  and  peculiar  rock  curiously 
resembling  the  eclogite  or  omphacite  rock  of  Hof,  in  Bavaria,  as  Professor 
Shepard  had  noted  in  his  early  article  in  1872. 

Both  these  localities  have  also  been  recently  described,  with  maps,  in 
the  admirable  report  of  Dr.  J.  H.  Pratt  and  Prof.  J.  V.  Lewis,  elsewhere 
referred  to.16 

The  resemblance  in  the  occurrence  of  the  North  Carolina  corundum  to 
that  of  Mramorsk  in  the  Ural  Mountains,  as  described  by  Prof.  Gustav 
Rose  of  the  University  of  Berlin,  has  been  shown  by  Professor  Genth.17 
There  the  associated  species  are  serpentine  and  chlorite  schist,  sometime? 
with  emery,  diaspore,  and  zoisite,  very  similar  to  the  chrome  serpentine 
corundum  belt  of  the  Southern  States.  The  emery  deposits  of  Asia  Minor 
and  the  Grecian  Archipelago,  according  to  Dr.  J.  Lawrence  Smith,18  yield 
that  substance  in  marble  or  limestone,  overlying  gneissic  rocks;  while 
with  it  are  associated  many  of  the  same  hydromicaceous  and  chloritic 
species  that  accompany  both  the  New  England  emery  and  the  southern 
corundum. 

With  more  particular  reference  now  to  the  actual  gems  yielded  at  these 
various  localities,  we  may  note  that  they  occur  in  two  distinct  forms: 
first,  as  crystals,  of  which  the  usual  forms  for  sapphire  are  doubly  termi- 

16  Corundum  and  the  Peridotites  of  North  Carolina,  N.  C.  Geol.  Surv.,  Vol.  I,  1905. 

17  Contributions  to  the  Laboratory  of  Penn.  Univ.,  No.  1,  1873. 

M  Am.  Jour.  Sci.,  II,  Vol.  X,  p.  355,  Nov.,  1850  ;  and  Vol.  XII,  p.  53,  Jan.,  1851. 


N.    C.    GEOLOGICAL   AND   ECONOMIC    SURVEY 


BULLETIN    NO.    12.       PLATE   IV 


A.    TRANSPARENT    BLUE    AND    GREEN    SAPPHIRE,    NATURAL    SIZE,     MACON    COUNTY,     N.     C. 


15.    CORUNDUM,    SHOWING    ALTERATION,    NATURAL   SIZE,    HAYWOOD    COUNTY,    N.    C. 


CORUNDUM   GEMS.  17 

nated  hexagonal  pyramids,  often  barrel-shaped  by  the  occurrence  of  a 
number  of  pyramidal  planes  of  successively  greater  angle;  and  second, 
as  nodules  of  purer  and  clearer  material,  in  the  midst  of  larger  masses  of 
ordinary  cleavable  corundum.  These,  when  broken  or  falling  out,  are 
sometimes  taken  for  rolled  pebbles,  which  they  resemble.  This  latter, 
and  quite  peculiar  mode  of  occurrence  is  treated  of  somewhat  in  the  able 
paper  on  this  mine,  read  by  Prof.  Eossiter  W.  Eaymond,  in  May,  1876, 
before  the  American  Institute  of  Mining  Engineers,  and  published  in 
their  Transactions. 

In  regard  to  the  relations  of  different  kinds  of  corundum,  Dr.  Pratt 
says : — "  The  corundum  gem  or  sapphire  localities  are  usually  distinct 
from  corundum  localities,  although  very  handsome  gems  have  been  found 
where  corundum  was  mined  for  abrasive  purposes,  notably  at  the 
Corundum  Hill  mine."  19 

In  1874,  Mr.  C.  W.  Jenks  read  a  paper  on  the  occurrence  of  sapphires 
and  rubies  in  situ  in  corundum,  at  the  Culsagee  mine,  before  the  Geolog- 
ical Society  of  London;  in  this  brief  but  important  article  he  described 
the  location  and  mineralogical  character  of  the  mine,  and  the  fact  of  the 
presence  of  portions  in  the  corundum  of  true  gem  quality.  The  paper 
attracted  much  interest,  and  Prof.  David  Forbes  said  that  great  credit 
was  due  to  Mr.  Jenks,  and  that  he  had  "  discovered  the  actual  home  "  of 
the  true  ruby  and  sapphire,  which  had  never  before  been  really  traced 
to  their  sources  (see  PL  I). 

Some  years  later,  a  London  periodical  made  the  statement  that  any  one 
who  found  the  sapphire  or  the  ruby  in  its  original  matrix  would  be 
called  the  "  King  of  Rubies,"  and  that  his  fortune  would  be  assurred. 
But  such  is  not  always  the  result  to  those  who  deserve  it.  Mr.  Jenks  was 
undoubtedly  the  original  finder  of  the  true  corundum  or  sapphire  gems- 
in  place,  and  he  obtained  from  this  locality  nearly  all  the  fine  crystals  of 
the  best  American  collections.  One  of  the  most  interesting  of  these  is  a 
piece  of  blue  corundum  with  a  white  band  running  across  it  and  a  place 
in  the  center  where  a  nodule  had  dropped  out.  This  piece  was  cut  and 
put  back  in  its  place,  and  the  white  band  can  be  seen  running  across  both 
gem  and  rock.  (See  colored  PL  1.)  Nearly  all  the  fine  gems  from 
Franklin,  N.  C,  were  brought  to  light  by  Mr.  Jenks'  mining;  but 
although  found  in  their  original  matrix,  they  were  of  such  rare  occur- 
rence that  it  was  found  unprofitable  to  mine  for  them  alone.  The  work 
was  subsequently  suspended  for  some  time  in  consequence  of  the  financial 
crisis  of  1873,  but  resumed  by  the  Hampden  Emery  Company. 

18  Corundum  in  the  United  States,  J.  H.  Pratt,  1901,  p.  10  (Bull.  No.  180,  U.  S.  Geol. 
Survey). 


18  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

The  largest  crystal  ever  found,  which  is  5  times  larger  than  any  other 
known,  is  one  early  discovered  by  Mr.  Jenks  and  described  by  Professor 
Shepard.20  It  is  now  in  the  cabinet  at  Amherst  College:  but  much 
injured  by  the  disastrous  fire  of  1882,  which  destroyed  so  many  fine 
specimens  of  the  Shepard  collection.  It  weighed  312  pounds,  and  meas- 
ured 22  inches  in  length,  18  inches  in  breadth,  and  12  inches  in  thickness. 
In  form  it  was  a  steep  and  somewhat  irregular  six-sided  pyramid,  termi- 
nated above  by  a  rather  uneven  basal  plane.  Its  general  color  is  grayish 
blue. 

In  addition  to  these  and  other  notable  crystals,  many  public  collections, 
besides  the  American  Museum  of  Natural  History  (which  possesses 
much  the  finest  series),  contain  numerous  cut  gems  from  this  mine. 

A  blue  stone  of  over  1-carat  weight  is  in  the  United  States  Xational 
Museum  at  Washington,  and  a  series  of  fine  red  and  blue  crystals  have 
been  deposited  there  by  S.  F.  Lucas.  In  the  collection  made  by  the  late 
Prof.  Joseph  Leidy,  of  Philadelphia,  and  now  also  in  the  Xational 
Museum,  are  several  gems  from  the  same  mine,  including  a  wine-yellow 
sapphire  of  3£  carats  (660  milligrams)  ;  a  violet-blue  stone  of  a  little 
over  1  carat  (215  milligrams)  ;  and  three  dark-blue  ones  weighing 
respectively  about  1^  (320  milligrams)  ;  1J  (250  milligrams)  ;  and  J 
(145  milligrams)    carats  each. 

In  Dr.  Spencer's  notes  on  American  gems  in  the  British  Museum  of 
Xatural  History,  London,  is  noted  a  specimen  of  corundum  from  Corun- 
dum Hill,  Macon  County,  X.  C,  which  consists  of  a  rough  hexagonal 
prism,  26  cm.  long  and  18  cm.  across,  of  a  reddish  color. 

In  a  recent  report  of  Prof.  J.  H.  Pratt,  State  Geologist,  he  thus  refers 
to  gems  from  this  locality  : 

At  the  Corundum  Hill  Mines,  Cullasagee,  N.  C,  various  shades  of  gem 
ruby  corundum  have  been  found.  Two  of  the  best  rubies  of  good  color  that 
have  ever  been  found  at  this  mine  are  in  the  collection  of  Clarence  S. 
Bement,  of  Philadelphia;  there  are  also  a  number  of  fine  ones  in  the  United 
States  National  Museum  at  Washington.  Many  of  the  smaller  crystals  of 
various  shades  of  pink  to  red  are  transparent  near  the  outer  surface  and 
near  their  extremities,  and  from  these  small  gems  can  be  cut,  but  few  that 
are  worth  $100  have  been  obtained  from  them. 

Probably  the  finest  emerald  green  colored  sapphire  in  the  world  came 
from  the  Culsagee  mine  sand  is  now  in  the  Morgan-Bement  collection  at 
Xew  York.  This  is  the  rarest  of  all  the  colors  of  sapphire  or  corundum 
gems,  and  is  known  as  Oriental  emerald.     The  specimen  is  a  crystal 

20  Am.  Jour.  Set,  IV,  Aug.  and  Sept.,  1872. 


CORUNDUM   GEMS.  19 

4  x  2  x  1 J  inches ;  part  of  it  is  transparent,  and  several  very  fine  gems 
could  be  cut  from  it,  see  Plate  XII. 

Another  locality  in  the  same  county,  interesting,  though  less  prominent, 
is  the  Mincey  mine  on  Ellijay  (properly  Elegee)  Creek,  about  2  J  miles 
northeast  of  Corundum  Hill.  Some  good  ruby  corundum  occurs  here, 
together  with  a  peculiar  brown  or  bronze  variety,  known  locally  as  "  pearl 
corundum,"  which  shows  distinct  asterism,  both  by  natural  and  artificial 
light,  when  the  stone  is  cut  en  cabochon.  In  natural  light  these  corun- 
dums  all  show  a  bronze  luster  and  are  somewhat  similar  to  the  catVeye, 
but  in  artificial  light  the  star  is  more  distinct.  Most  of  the  bronze  -corun- 
dum is  in  rough  crystals,  but  some  have  been  found  that  have  the  prismatic 
faces  smooth  and  well  developed,  and  these  are  often  dark,  almost  black, 
in  color.  One  crystal  of  this  dark  kind,  found  some  years  ago,  yielded 
gems  §  of  an  inch  in  diameter.  A  similar  asterism  has  been  noticed  in 
many  of  the  rubies  and  sapphires  from  Cowee  Valley,  and  at  several 
other  points  in  the  State.  According  to  Von  Lasaulx,  it  is  some- 
times produced  by  rifts  due  to  the  basal  parting.  These  rifts  when 
examined  with  the  microscope,  are  seen  to  be  very  thin,  sharp  and  recti- 
linear, and  are  parallel  to  the  edge  between  the  prism  and  the  base.  In 
other  cases  asterism  is  undoubtedly  due  to  rutile  or  other  minute  crystals 
enclosed  in  the  corundum,  intersecting  each  other  at  an  angle  of  60°,  or  in 
some  similar  systematic  positions. 

At  the  Cullakenee  mine,  Buck  Creek,  in  Clay  County,  masses  of  emerald 
to  grass-green  amphibolite  (also  called  smaragdite)  are  found,  through 
which  are  disseminated  particles  of  pink  and  ruby  corundum,  from  the 
size  of  a  pea  to  some  as  large  as  hickory  nuts.  The  corundum  is  not  of 
gem  quality,  but  the  combination  of  the  green  and  pink  makes  very 
beautiful  specimens,  and  as  the  rock  is  hard  enough  to  take  a  good  polish, 
it  might  furnish  a  decorative  or  ornamental  stone  of  some  value.  It  has 
been  introduced  for  such  purposes  under  the  name  of  ruby  matrix. 

A  similar  association  of  green  amphibolite  with  corundum,  sometimes 
pink  and  sometimes  dark  blue,  is  found  near  Elf  post-office,  on  Shooting 
Creek,  in  the  same  county.  Other  corundum  localities  in  Clay  County  are 
the  Foster  mine,  near  the  headwaters  of  the  north  fork  of  Shooting  Creek, 
and  the  Herbert  mine  on  Little  Buck  Creek. 

Of  late  much  attention  has  been  aroused  by  the  discovery  of  rich  ruby 
corundum  in  small  distinct  crystals  of  a  different  character  from  any 
others  found  in  the  State,  and  in  a  different  rock.  These  have  been  known 
as  the  Cowee  rubies,  from  the  locality  in  the  Cowee  valley,  in  Macon 
County.  It  has  seemed  as  though  here,  at  last,  true  gem  rubies,  equal  to 
those  of  Burma,  had  been  really  found,  and  much  interest  has  been  felt  in 


20  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

the  discovery.  Thus  far,  however,  no  very  important  results  have  been 
obtained,  although  some  of  the  stones  are  unquestionably  fine,  but  most  of 
them  are  small  (see  PI.  I). 

They  are  unusually  interesting  and  beautiful  as  crystals,  but  many  of 
them  are  imperfect.  It  is  claimed,  however,  that  the  percentage  of 
imperfect  stones  is  no  greater  than  it  is  in  the  rubies  from  Burma. 
Unfortunately,  many  of  the  crystals  also  have  inclusions  which  mar  their 
elegance  as  gems.  The  exact  locality  of  this  very  interesting  occurrence  is 
a  tract  of  some  10  square  miles  lying  between  Mason's  Branch  and 
the  Caler  Fork  of  Cowee  Creek,  affluents  of  the  Little  Tennessee  River 
some  6  miles  below  Franklin,  Macon  County.  Many  interesting  minerals 
are  found  in  this  area,  and  there  are  mica  mines  there,  and  mines  where 
the  abundant  garnet  has  been  worked  for  use  as  an  abrasive.  The 
beautiful  rhodolite  garnets,  found  in  close  association  with  the  ruby 
crystals  in  the  gravel  and  saprolite,  will  be  described  separately  under 
garnet. 

The  discovery  and  development  of  the  "  Cowee  rubies "  were  first 
described  in  the  volumes  of  the  TJ.  S.  Geological  Survey  (Mineral 
Resources  of  the  United  States),  in  the  writer's  annual  reports  on  the 
Production  of  Precious  Stones,  from  1893  to  1896,  year  by  year,  and 
further  in  that  of  1899.21  Also  in  1899,  there  appeared  a  full  account  by 
Prof.  J.  W.  Judd,  Mr.  W.  E.  Hidden,  and  Dr.  J.  H.  Pratt22;  and  the 
latter  gentleman  has  since  published  further  accounts  in  his  annual 
reports,  and  in  his  special  bulletins  on  corundum  in  the  United  States.2" 

The  first  published  notice  in  the  author's  report  for  1893,  above 
mentioned,  was  of  the  finding  of  ruby  corundum,  in  small  hexagonal 
crystals,  flat  or  tabular,  in  an  alluvial  deposit  on  the  Reeves  farm,  not  far 
from  Franklin,  associated  with  beautiful  garnets.  The  next  years  report 
described  the  locality  as  consisting  of  the  valley  of  a  stream,  for  several 
miles,  in  which  the  rubies  were  distributed  through  a  gravel  bed  from 
2  to  10  feet  thick,  overlain  by  several  feet  of  surface  deposit. — a  mode 
of  occurrence  very  similar  to  that  in  the  Mogok  Valley  in  Burma,  where 
the  finest  rubies  are  obtained. 

The  attention  of  the  author  was  first  called  to  these  rubies  by  the  late 
Mr.  James  D.  Yerrington,  of  New  York,  who  had  specimens,  both  cut 
and  uncut,  that  he  had  received  from  Mr.  Reeves,  of  Athens.  Georgia, 
who  owned  the  farm  on  which  they  had  been  found.  Two  cut  gems  of 
\  a  carat  each,  were  set  in  a  flag  scarf-pin  shown  in  the  Tiffany  jewelry 

21  Mineral  Resources  U.  S.,  Ann.  Reps.  U.   S.  G.  S.,   1893,  1894,  1895,  1896.  1899. 

22  Am.  Jour.  Sci.,  IV,  Vol.  VIII,  Nov.  1899,  pp.  370-380. 

23  Bulls.  U.  S.  Geol.  Survey,  No.  180,  1901  and  No.  269,  1906. 


CORUNDUM    GEMS.  21 

S 

exhibit  at  the  Columbian  Exposition  of  1893;  these  were  subsequently 
unmounted  and  displayed  by  the  same  firm  at  the  Atlanta  Exposition  of 
1895.  They  now  form  part  of  the  Tiffany-Lea  collection,  included  in 
that  of  the  U.  S.  National  Museum  at  Washington.  A  number  of  others 
(see  figures),  obtained  at  about  the  same  time,  are  in  the  American 
Museum  of  Natural  History,  New  York.  A  fine  series,  both  of  crystals 
and  cut  gems,  was  shown  by  the  North  Carolina  Geological  Survey  at  the 
recent  Expositions  at  Buffalo,  1901,  Charleston,  1901-02,  and  St.  Louis, 
1904. 

In  1896,  the  locality  was  visited  and  examined  by  Mr.  C.  Barrington 
Brown,  the  eminent  authority  on  ruby  mining,  who  had  previously  pre- 
pared an  exhaustive  report  on  the  Burma  region,  in  conjunction  with 
Prof.  J.  W.  Judd,  for  the  British  Government. 

In  1899,  as  above  stated,  Professor  Judd  and  Mr.  William  E.  Hidden 
published  a  joint  article,  with  crystallographic  notes  by  Dr.  J.  H.  Pratt. 
This  account  embodied  the  results  of  Mr.  Brown's  visit,  of  Mr.  Hidden's 
operations  on  the  ground,  and  of  Dr.  Pratt's  studies  on  the  crystal  forms 
and  their  relations.  It  had  now  become  clear  that  the  rubies  from  this 
locality  occurred  in  a  wholly  different  association  from  any  other  corun- 
dum in  the  State,  and  the  title  of  the  article  was  "  On  a  New  Mode  of  Oc- 
currence of  Euby  in  North  Carolina."  The  surrounding  rocks  are  schists 
and  gneisses,  often  containing  corundum,  but  in  elongated  crystals  and 
not  of  gem  quality.  Only  a  few  miles  away  are  the  dunite  outcrops  of  the 
Culsagee  and  other  localities,  already  described.  But  at  Cowee  the  rock 
is  wholly  different,  and  the  forms  of  the  crystals  also.  The  first  accounts 
had  reported  a  limestone  as  the  probable  source  of  the  valley  deposit, 
and  even  as  the  matrix  of  the  crystals,  as  is  the  case  in  Burma.  But 
further  study  had  disproved  this  statement.  Underneath  the  ruby-bearing 
gravel,  comes  a  soft  decayed  rock  to  which  the  name  of  saprolite  has  been 
given, — a  result  of  the  decomposition  of  basic  igneous  rocks,  in.  place. 
This  is  sometimes  many  feet  in  thickness,  but  gradually  passes  downward 
into  the  unaltered  condition  of  the  same  rocks.  Trial  shafts  show  that 
this  change  begins  from  a  depth  of  some  35  feet,  when  portions  of  the 
unaltered  rock  begin  to  be  met  with.  The  original  rock,  when  reached, 
proves  to  consist  of  several  related  varieties,  comprising  amphibolite, 
hornblende-eclogite  (garnet-amphibolite  of  some  authors),  and  a  basic 
hornblende-gneiss,  with  some  feldspars  (labradorite  and  perhaps  anor- 
thite).  Some  of  these  rocks  are  doubtless  the  source  of  the  rubies  strewn 
through  the  saprolitic  material  and  the  overlying  gravel,  though  their 
actual  occurrence  in  the  undecomposed  rock  has  not  vet  been  proved. 
The  crystals  are  distinct  from  any  others  found  in  North  Carolina,  but 


22  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLIXA. 

resemble  in  form  those  from  Yogo  Gulch,  Montana  (the  sapphire  variety) 
which  are  taken  from  true  igneous  dikes;  and  these  flat  and  tabular 
hexagonal  forms  are  regarded  by  students  of  crystallography  as  character- 
istic of  corundum  that  has  solidified  from  a  molten  igneous  rock. 

Another  corundum  occurrence  in  saprolitic  rock,  but  the  crystals  blue 
and  more  prismatic,  is  noted  by  Dr.  Pratt  at  the  Seed,  or  Watauga  mine, 
6  miles  east  of  Franklin;  and  red,  sometimes  ruby,  corundum  is  found 
in  old  stream  gravels  near  West  Mills;  both  of  these  are  in  Macon 
County.  A  number  of  minor  occurrences  are  known  throughout  the 
general  region,  where  there  are  small  saprolitic  areas. 

There  are  many  other  localities  of  corundum  in  this  group  of  counties, 
some  of  the  more  important  or  promising  of  which  may  be  simply  men- 
tioned here.  In  Macon  County,  besides  the  important  occurrences  already 
described,  corundum  appears  at  Glenville,  in  chlorite  schist;  at  Xona, 
on  Thumping  Creek,  in  nodules  and  flat  crystals  in  gneiss;  on  Hickory 
Knoll  Creek  at  an  elevation  of  4,000  feet  on  Fishhawk  Mountain,  in 
dunite ;  and  at  the  Coweeta  mine,  of  pink  color  in  greenish  cyanite.  Of 
late,  the  emery  variety  has  been  found,  and  to  some  extent  worked,  at 
several  points  near  Fairview  Knob,  in  a  basic  magnesian  rock,  the  prin- 
cipal mine  being  the  Fairview,  near  North  Skeener  Gap,  and  the  Waldroop 
mine  on  Dobson  Mountain. 

Jackson  and  Transylvania  counties  have  numerous  corundum  localities, 
notably  in  the  region  along  their  border,  where  the  town  of  Sapphire  has 
been  named,  and  the  appellation  of  the  Sapphire  country  is  frequently 
used.  Here  are  found  many  outcrops  of  peridotite,  with  a  general  X.E.- 
S.W.  course,  and  frequently  associated  with  corundum.  One  locality  that 
gives  some  promise  is  the  so-called  gem  mine  on  the  property  of  Dr. 
Grimshawe,  of  Montvale.  This  has  been  known  and  to  some  extent 
worked,  for  many  years.  Eubies  of  good  color,  from  which  a  number  of 
fine  but  very  small  stones  have  been  cut,  have  been  found  here  in  the 
gravels  of  the  stream,  together  with  blue  and  yellow  corundum  of  gem 
quality.  By  following  up  the  gravels  the  corundum  was  located  in  a  small 
vein  in  the  decomposed  peridotite. 

At  the  Sapphire  and  Whitewater  mines,  near  Sapphire,  fragments  of 
corundum  of  a  fine  blue  color  have  been  found,  from  which  small  but  good 
gems  have  been  cut. 

Quite  large  amounts  of  commercial  corundum  have  been  taken  out  at 
the  Bad  Creek  and  Socrates  mines,  and  also  at  the  Burnt  Bock  and 
Brockton  mines;  these  two  are  in  Transylvania  County,  the  others  being 
in  Jackson  County,  and  all  in  peridotite.  Other  associations  in  Jackson 
County  are,  along  Caney  Fork  and  Chastain's  Creek,  in  chlorite  schist; 
and  at  Bett's  Gap  in  translucent  grayish-white  crystals  in  gneiss. 


CORUNDUM   GEMS.  23 

In  Haywood  County,  2  miles  northeast  of  Pigeon  river,  near  the  cross- 
ing of  the  Asheville  road,  and  2  miles  north  of  this,  on  the  west  fork  of 
Pigeon  Eiver,  at  Presley  mine,  are  found  some  of  the  finest  colored 
specimens  of  blue  and  grayish-blue  corundum,  in  a  pegmatitic  dike,  and 
also  near  Eetreat  post-office  (see  PI.  IV,  B).  At  Newfound  Gap,  red 
corundum  occurs  in  an  outcrop  of  dunite. 

Twenty  miles  northeast  of  the  Presley  is  the  Carter  mine  in  Buncombe 
County,  where  fine  white  and  pink  corundum  occurs  in  crystals  and  in  a 
laminated  form  in  peridotite.  Blue,  bluish-white,  and  reddish  varieties 
occur  at  Swannanoa  Gap ;  and  also  a  little  south  of  the  town  of  Democrat, 
corundum  appears, — all  in  the  same  or  similar  rock. 

Yancey  County  has  several  localities,  the  most  noted  of  which  are 
Celos  Eidge,  8  miles  southeast  of  Burnsville,  where  crystals  occur  in  a 
decomposed  gneiss,  and  Egypt,  10  miles  west  of  the  same  town,  where 
white  crystals,  sometimes  mottled  with  blue,  are  found  directly  in  the 
decomposed  peridotite  (dunite).  This  occurrence  is  noted  as  of  much 
interest,  by  Lewis1  and  Pratt,2  for  although  corundum  is  very  largely 
associated  with  the  rock,  the  crystals  are  rarely  found  actually  enclosed 
in  it. 

Northeast  of  these  mines,  in  the  line  of  strike  of  the  whole  country 
rock,  corundum  is  found  in  gneiss  near  Bakersville,  in  Mitchell  County ; 
and  also  southwest,  in  Madison  County,  near  Marshall,  a  little  north  of 
where  Big  Ivy  Eiver  enters  the  French  Broad;  here  the  rock  is  amphib- 
olite. 

Grouped  together  under  the  name  of  the  Blue  Eidge  tract,  are  a 
number  of  localities  where  the  corundum  occurs  in  long  bands  of  quartzose 
schist  that  belong  in  and  with  the  gneisses  among  which  they  occur.  This 
was  referred  to  before  as  a  very  distinct  mode  of  occurrence,  in  that  the 
rocks  are  altered  sediments,  and  the  corundum,  a  product  of  metamorphic 
action  rather  than  igneous.  These  corundiferous  schists  have  been  traced 
for  many  miles  along  the  crest  of  the  Yellow  and  Chunkygal  mountains. 
The  content  of  corundum  is  very  small,  and  these  deposits  will  not  be 
important  sources  for  some  time  to  come.  Dr.  Pratt  makes  4  local  divi- 
sions ; — The  Scaly  Mountain  tract,  at  an  elevation  of  some  4,500  feet 
on  the  southern  and  southwestern  slopes  of  those  mountains,  near  the 
headwaters  of  Beech  Creek,  a  tributary  of  the  Tallulah ;  the  Foster  tract, 
just  over  the  line  in  Georgia;  the  Yellow  Mountain  tract,  on  the  northern 
slopes  of  those  mountains ;  and  the  Chunkygal  tract,  near  the  headwaters 
of  Sugar  Cove  Creek,  on  the  western  slopes  of  the  mountains.    The  first 

1Bull.  11,  N.  C.  Geological  Survey. 
2  Bull.  269,  U.  S.  Geological  Survey. 


24  HISTORY    OF    THE    GEMS    FOUND   IN    NORTH    CAROLINA. 

two  have  been  worked  somewhat,  by  the  Corundum  Mining  &  Manufac- 
turing Co.,  of  Philadelphia.  These  localities  are  all  near  the  southern 
border  of  the  State,  and  pass  over  into  Rabun  County,  Georgia. 

The  Piedmont  Counties. — As  was  stated  above,  corundum  was  early 
found  at  some  points  east  of  the  mountains ;  and  the  references  to  discov- 
eries and  collecting  by  Dr.  C.  L.  Hunter,  Prof.  J.  A.  Humphreys,  and 
Prof.  Brumby  of  Columbia,  S.  C,  antedate  the  Civil  War  by  about  10 
years.  Since  the  new  epoch  of  mineral  development  set  in  after  the 
return  of  peace,  further  discoveries  have  been  made,  all  of  interest,  but 
none  as  yet  of  importance.  Mr.  J.  A.  D.  Stephenson  obtained  fine 
hexagonal  prisms  of  pale  brown  corundum  at  Belt's  Ridge,  near  States- 
ville,  Iredell  Co.,  and  some  crystals  of  fine  colors  from  other  neighboring 
points.  Prof.  Lewis  mentions  a  black  corundum  in  amphibolite,  on  the 
Hunter  farm,  8  miles  north  of  Statesville,  another  occurrence  in  the 
same  rock,  at  the  Acme  mine,  and  a  pink  corundum  in  cyanite  at  the 
Collins  mine,  both  in  the  same  vicinity.  An  old  locality,  especially  noted 
by  Professor  Humphreys,  is  Shoup's  Ford,  in  Burke  Co.,  where  the 
corundum  is  associated  with  fibrolite,  which  sometimes  surrounds  or 
encloses  the  crystals,  forming  what  Professor  Humphreys  described  as 
"pods."  In  Gaston  County,  bine  corundum  occurs  with  quartz  and 
mica,  at  Crowders  Mountain  and  Chubbs  Mountain;  the  latter  is  the 
source  of  the  Brumby  specimens  in  1852;  it  was  then  known  properly 
as  Clubb  Mountain,  named  from  an  old  resident  and  Revolutionary 
patriot. 

Corundum  in  grayish-blue  crystals  in  garnet-bearing  schists  and  gneisses 
is  reported  from  points  along  the  ridge  stretching  from  Carpenter's  Knob, 
northwest,  on  the  borders  of  Burke,  Catawba,  and  Cleveland  counties. 


CHAPTER  IV. 

GEM  MINERALS  OF  THE  PEGMATITIC  DIKES. 

In  the  pegmatite  veins  of  North  Carolina  are  found  so  many  minerals 
of  gem  value  1  that  a  short  description  of  these  dikes  is  given  here. 

These  pegmatitic  veins  are  interesting  not  only  from  a  commercial 
standpoint  on  account  of  the  value  of  the  mica  obtained,  but  also  from  a 
mineralogical' standpoint  on  account  of  the  variety  of  minerals  that  they 
sometimes  contain. 

In  character  these  pegmatitic  dikes  are  very  similar  to  a  granite  and 
have  sometimes  been  called  "  coarse  granite  "  and,  if  we  could  conceive 
of  the  constituents  of  a  granite  magnified  a  hundred  times  or  more, 
we  would  have  an  appearance  that  is  very  similar  to  a  pegmatitic  dike. 
The  main  mineral  constituents  of  these  dikes  are  quartz,  feldspar,  and 
muscovite  mica  in  varying  proportions,  sometimes  being  nearly  equally 
distributed  while  in  others  sometimes  one  and  again  another  will  pre- 
dominate. Sometimes  the  feldspar,  quartz,  and  mica  have  separated  out 
in  rather  small  masses  while  at  other  times  they  have  separated  out  on  a 
larger  scale  and  are  more  or  less  crystallized. 

The  associated  minerals  that  occur  in  these  dikes  vary  with  their  occur- 
rence and  while  in  some  there  is  a  great  variety  of  •them,  in  others  they 
are  very  rare.  The  pegmatitic  dikes  that  are  observed  in  North  Carolina 
have  furnished  the  greatest  variety  of  accessory  minerals,  45  having  been 
observed  from  the  different  veins,  at  a  number  of  which  over  20  different 
minerals  have  been  observed.  Of  these  accessory  minerals  the  garnet 
(either  andradite  or  almandite)  is  by  far  the  commonest  and  is  often  the 
only  accessory  mineral  observed. 

The  accessory  minerals  in  these  pegmatitic  dikes  are  usually  well 
crystallized  and  a  number  of  them  are  gem  minerals.  The  following  is  a 
list  of  the  minerals  that  have  been  identified  in  the  mica-bearing 
pegmatitic  dikes  in  North  Carolina  and  they  are  given  approximately 
according  to  their  relative  frequency  of  occurrence : 

Quartz     (massive,    crystallized    and      Zoisite   (var.  thulite). 

smoky).  Menaccanite. 

Albite,  Feldspar.  Rogersite. 

1  Joseph  Hyde  Pratt  in  "  The  Southland,"  Asheville,  North  Carolina,  August,  1001,  pp. 
120-121. 


26 


HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 


Microcline,  Feldspar. 
Oligoclase,  Feldspar. 
Orthoclase,  Feldspar. 
Kaolin. 

Beryl   (Emerald,  yellow,  and  aqua- 
marine). 
Muscovite,  Mica. 
Biotite,  Mica. 
Essonite,  Garnet. 
Almandite,  Garnet. 
Andradite,  Garnet. 
Tourmaline. 
Apatite. 
Columbite. 
Allanite. 
Epidote. 
Samarskite. 
Gummite. 
Autunite. 
Pyrite. 
Magnetite. 


Hatchettolite. 

Fergusonite. 

Uraninite. 

Uranotil. 

Phosphuranylite. 

Monazite. 

Zircon. 

Pyrrhotite. 

Hematite. 

Limonite. 

Rutile. 

Molybdenite. 

Opal  (var.  hyalite) 

Enstatite. 

Actinolite. 

Cyanite. 

Gahnite. 

Chabazite.(?) 

Graphite. 

Pyrophyllite. 


Of  the  minerals  given  in  this  list  the  following  have  been  found  of 
sufficient  purity  to  be  a  source  of  gems : 
Essonite.  Albite. 

Almandite.  Oligoclase. 

Beryl.  Orthoclase. 

Quartz.  Gahnite. 


The  following  of  these  pegmatite  occuring  minerals  are  precious  stones : 


Albite,  Feldspar. 
Almandite,  Garnet. 
Beryl   (Emerald,  yellow,  and  aqua- 
marine). 
Cyanite. 

Essonite,  Garnet. 
Opal  (var.  hyalite). 
Pyrite. 


Quartz,    (massive,    crystallized    and 

smoky). 
Menaccanite. 
Microcline. 
Oligoclase,  Feldspar. 
Rutile. 
Zircon. 


The  following  are  radio-active : 

Allanite.  Monazite. 

Autunite.  Phosphuranylite. 

Columbite.  Rogersite. 

Fergusonite.  Samarskite. 

Gummite.  Uraninite. 

Hatchettolite.  Uranotil. 
Menaccanite. 


Plate  No   V 


Smoky  quartz 

( cairngorm  stone), 
AlexanderCounh/,  North  Carolina 


iu 1 1 late d  Quariz. 

Alexander  County, 
North  Carolina 


Elutiloted  Quartz 

Alexander  County, 
North  Carolina 


D       E 

Amethyst 

Henry  Lincoln  County 
North  Carolina. 


Amethyst. 
TesantyCn 
Smith  Bridgelbwnship, 
Macon Cbunty,  NorthCaioIina. 


i  by'lhliei  Prang  Art  lo 


.Vepsrw  undei  II 


GEM    MINERALS    OF    THE    PEGMATITIC    DIKES.  SJ'7 

The  following  are  commercial  minerals : 

Graphite.  Muscovite  (mica). 

Kaolin.  Orthoclase. 

Magnetite.  Pyrophyllite. 

It  is  the  breaking  down  of  these  veins  that  form  many  of  the  smaller 
often  microscopic  minerals  found  in  the  detritis  of  the  gold  veins. 

THE    FELDSPARS. 

Several  interesting  varieties  of  feldspar  occur  in  North  Carolina, 
among  which  the  following  may  be  especially  noted  as  the  ones  which  are 
of  importance  as  gem  material. 

Orthoclase. — A  very  interesting  variety  of  sunstone  was  found  by  J.  A. 
D.  Stephenson  at  the  quarry  in  Statesville,  N.  C;  the  reflections  are  as 
fine  as  those  of  the  Norwegian,  but  the  spots  of  color  are  very  small. 
Several  hundred  dollars'  worth  from  this  locality  have  been  sold  as  gems. 

Microcline. — This  feldspar  is  closely  related  to  orthoclase;  it  is  some- 
times of  a  very  beautiful  light  green  color,  and  is  then  known  as  amazon- 
stone,  and  valued  for  cutting  and  polishing  for  ornamental  purposes. 
Several  localities  in  North  Carolina  furnish  this  mineral,  especially  the 
Eay  mica  mine,  Yancey  County. 

Oligoclase. — In  December,  1887,  specimens  of  feldspar  were  sent  to  the 
writer2  by  Daniel  A.  Bowman,  who  had  found  them  at  a  depth  of  380 
feet  in  the  Hawk  Mica  mine,  4  miles  east  of  Bakersville,  N.  C.  They 
proved  to  be  a  variety  of  oligoclase,  remarkable  for  its  transparency.  The 
clearest  piece  measured  1  by  2  by  3  inches.  One  of  the  two  varieties 
is  of  a  faint  window-glass  green  color,  and  contains  a  series  of  cavities, 
surrounded  and  fringed  by  tufts  of  white,  needle-shaped  inclu- 
sions called  microlites;  these  tufts  vary  from  1/50  to  3/50  inch  (0.5  to 
1.5  millimeter)  in  diameter  and  are  quite  round,  resembling  those  that 
are  occasionally  present  in  the  Ceylonese  moonstone.  The  wonderful 
transparency  of  the  oligoclase  and  the  whiteness  of  the  inclusions  give 
the  whole  mass  a  striking  resemblance  to  the  lumps  of  glass  so  commonly 
obtained  from  the  bottom  of  a  glass-pot.  It  was  mistaken  for  this  until 
its  highly  perfect  cleavage  was  noticed.  Recently  some  material  of  a 
slightly  different  character  has  been  obtained  at  the  mine.  Cleavage 
masses  of  a  white,  striated  oligoclase,  3  inches  long,  were  found  containing 
nodules  about  f  inch  to  f  inch  (10  to  15  millimeters)  across,  which  were 
as  colorless  and  pellucid  as  the  finest  phenacite  and  entirely  free  from 

2  See  Mineralogical  Notes,  by  George  F.  Kunz,  Am.  Jour.  Sci.,  Ill,  Vol.  XXXVI,  p.  222, 
Sept.,  1888. 


28  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

the  inclusions  found  in  the  greenish  variety.     This  translucent  variety, 
like  the  other,  shows  no  striae. 

The  following  analysis  by  Prof.  Frank  W.  Clarke,  made  from  a  faint 
green  variety,  shows  it  to  be  a  typical  oligoclase.  The  specific  gravity  was 
determined  to  be  2.651.  This  has  been  cut  into  a  transparent  gem,  and 
may  be  advantageously  used  for  spectroscope,  microscope,  and  other  lenses. 

Silica  62.60 

Alumina  23.52 

Ferric  Oxide 08 

Manganous  Oxide trace 

Lime   4.47 

Potassa 56 

Soda  8.62 

Loss  by  ignition 10 

99.95 

Labradorite  (Opalescent  feldspar). — On  the  road  to  Charlotte,  Mecklen- 
burg  County,  and  near  Bakersville,  Mitchell  County,  specimens  showing 
a  slight  blue  chatoyancy  are  found.  This  domestic  labradorite  is  scarcely 
used  at  all  in  the  arts,  as  the  mineral  from  Labrador  is  cheaper  and  of  a 
much  superior  quality,  and  takes  a  fine  polish. 

Leopardite. — This  is  a  rock  composed  largely  of  whitish  feldspar 
(orthoclase  and  plagioclase),  spotted  black,  perhaps  by  manganese  oxide, 
and  named  from  its  leopard-like  appearance.  It  is  abundant  near 
Charlotte,  Mecklenburg  County,  and  also  in  Gaston  County.  It  is  not 
a  definite  mineral,  but  a  variety  of  porphyry  with  disseminated  crystals 
of  quartz,  and  occurs  in  large  masses  as  a  rock,  so  that  it  would  furnish 
a  good  ornamental  stone,  if  polished.  This  variety  of  spotted  feldspar 
is  peculiar  to  North  Carolina,  and  has  been  described  in  detail  in  the 
report  on  Building  Stones. 

The  beryl,  zircon,  and  other  gem  minerals,  which  are  also  constituents 
of  pegmatitic  dikes,  are  described  in  the  following  chapters. 


CHAPTER  V. 

QUAKTZ  AND  OPAL. 

Quartz  in  its  various  crystalline  forms, — rock-crystal,  amethyst,  and 
smoky  quartz, — occurs  at  many  points  in  North  Carolina,  and  in  some 
cases  of  fine  quality  (PL  V).  The  non-crystalline  varieties,  such  as 
agate,  jasper,  etc.,  have  not,  on  the  other  hand,  been  found  to  any 
important  extent  in  the  State,  until  very  recently  in  the  chrysoprase 
workings  near  Asheville. 

CRYSTALLINE    VARIETIES. 

Rock-Crystal.- — Much  interest  was  created  in  1886,  when  a  remarkable 
mass  of  rock-crystal,  weighing  51  pounds,  was  sent  to  Tiffany  &  Com- 
pany, New  York.  It  purported  to  be  from  Cave  City,  Va.,  but  was 
subsequently  traced  with  certainty  to  the  mountainous  part  of  Ashe 
County,  N.  C.1  The  original  crystal,  which  must  have  weighed  300 
pounds,  was  unfortunately  broken  in  pieces  by  the  ignorant  mountain 
girl  who  found  it,  but  the  fragment  sent  to  New  York  was  sufficiently 
large  to  admit  of  being  cut  into  slabs  6  inches  square  and  from  half  an 
inch  to  an  inch  thick.  This  superb  crystal,  if  it  had  not  been  broken, 
would  have  furnished  an  almost  perfect  ball  4-J  or  5  inches  in  diameter. 
It  is  now  in  the  Morgan  Collection  at  the  American  Museum  of  Natural 
History,  New  York.  A  visit  to  the  locality  by  the  author  traced  this 
specimen  to  the  place  of  its  discovery  near  Long  Shoal  Creek,  on  a  spur 
of  Phoenix  Mountain  in  Chestnut  Hill  Township.  There  have  also  been 
found  at  2  places,  600  feet  apart  (about  1  mile  from  the  former  locality), 
2  crystals,  weighing  respectively  285  and  188  pounds.  The  larger  of  the 
2  was  29  inches  long,  18  inches  wide,  13  inches  thick,  showing  1  pyra- 
midal termination  entirely  perfect  and  the  other  less  complete.  All  these 
crystals  were  lying  in  decomposed  crystalline  rock  consisting  of  a  coarse 
feldspathic  granite,  and  were  obtained  either  by  digging  or  by  driving  a 
plow  through  the  soil.  Altogether  several  dozen  crystals  have  been  found 
in  this  vicinity  weighing  from  20  to  300  pounds  each,  and  future  working 
will  undoubtedly  reveal  more.  These  large  crystals  are  often  very  irregu- 
lar and  pitted,  like  many  of  those  from  St.  Gothard.     Of  those  now  in 

iProc.  Am.  Assoc'n  Adv.  Scl.,  Vol.  XXXV,  p.  239,  1886. 


30  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

the  Morgan-Tiffany  collection  at  New  York,  the  most  irregular  was  20-| 
pounds  in  weight,  with  the  entire  surface  rough  and  opaque  like  ground 
glass,  and  almost  spherical  in  form,  but  the  interior  perfectly  transparent. 
In  a  few  instances,  they  had  a  coating  of  rich  green  chlorite  that  pene- 
trated to  the  depth  of  an  inch.  This,  when  left  on  the  quartz,  gave  the 
cut  crystal,  after  polishing,  the  effect  of  a  pool  of  water  with  green  moss 
growing  on  the  bottom. 

Many  beautiful  articles  have  been  made  from  this  Ashe  County 
material.  One  was  an  elegantly  carved  vinaigrette  or  scent-bottle,  exhib- 
ited at  the  Paris  Exposition  of  1889.  A  crystal  ball  5  inches  in  diameter, 
and  a  number  of  art  objects,  all  of  American  workmanship,  made  from 
the  same  material,  were  shown  at  the  Columbian  Exposition  at  Chicago 
in  1893,  and  some  of  these  are  now  in  the  Tiffany  collection  in  Higin- 
botham  Hall,  in  the  Field  Columbian  Museum  in  that  city.  These  were 
all  made  in  the  Tiffany  ateliers  in  New  York. 

By  far  the  most  important  piece  from  this  locality,  however,  was  a 
magnificent  crystal  obtained  in  1888  by  the  author  at  the  same  locality. 
This  was  worked  up  into  a  special  design,  and  exhibited  as  the  finest 
piece  of  American  lapidary  work  ever  executed  in  rock  crystal.  It  was  the 
most  important  art  object  of  stone  at  the  great  Paris  Exposition  of  1900, 
where  it  was  shown  by  the  makers,  Tiffany  &  Company.  It  now  will  form 
part  of  the  F.  A.  Matthiesen  memorial  gift,  lately  presented  to  the 
Metropolitan  Museum  of  Art  in  New  York  City. 

Another  North  Carolina  locality  was  reported  in  1896,  by  Mr.  E.  M. 
Chatham,  who  described  crystals  up  to  40  pounds  in  weight,  from  Elkin, 
in  Surrey  County.  Some  large  crystals  are  also  known  from  South 
Carolina;  and  it  is  probable  that  a  good  deal  of  rock-crystal,  capable  of 
use  in  the  arts,  exists  in  the  mountain  region  of  the  South. 

The  report  of  the  finding  near  Bakersville  of  transparent  crystals  of 
quartz,  weighing  642  pounds  and  340  pounds  respectively,  was  premature, 
as  the  specimens  proved  to  be  veins  of  translucent  quartzite,  with  the 
crystalline  markings  of  a  group  rather  than  of  a  single  crystal.  The 
clear  spaces,  which  were  to  be  observed  only  on  these  crystalline  sides, 
would  hardly  afford  material  for  a  crystal  ball  an  inch  in  diameter,  and 
with  this  exception  they  are  almost  an  opaque  white,  with  flaws.  Notwith- 
standing this  error,  it  is  certain  that  some  localities  in  North  Carolina 
have  yielded  larger  masses  of  clear  rock-crystal  than  any  other  State 
in  the  Union,  until  the  recent  developments  in  Calaveras  County, 
California. 

In  Alexander  and  Burke  counties,  N.  C,  crystals  of  white  as  well  as  of 
smoky  quartz  have  been  found,  in  which  were  spaces  that  would  cut  into 


. 


N.    C.    GEOLOGICAL   AND    ECONOMIC    SURVEY 


BULLETIN    NO.    12.       PLATE    VI 


A.     QUARTZ     CRYSTALS     (SMOKY)      NATURAL     SIZE,     ALEXANDER     COUNTY,      N.     C. 


li.     AMETHYST,     LINCOLN      COUNTY,      N.     C. 


QUARTZ   AND  OPAL.  31 

clear  crystal  balls  of  from  2  to  2-|  inches  (PI.  VII,  A).  One  of  these 
from  Alexander  County,  measuring  2  3/16  inches,  is  in  the  State  Museum 
of  Natural  History  at  Albany,  N.  Y.  A  very  interesting  bead  made  of 
rock-crystal,  fluted  and  drilled  from  both  ends,  is  in  the  collection  of 
A.  E.  Douglas,  in  New  York  City.  It  is  evidently  native  work,  as  it  is 
improbable  that  foreign  traders  would  use  white  rock-crystal  beads,  when 
glass  would  answer  the  purpose  as  well. 

The  Indians  who  lived  in  North  Carolina  previous  to  the  advent  of 
the  white  man  occasionally  noticed  quartz  crystals,  as  is  shown  by  some 
being  found  in  the  mounds.  They  also  realized  the  beautiful  cutting  edge 
that  this  material  would  possess  if  it  were  chipped  in  the  form  of  an  arrow 
point;  and  so  they  used  up  great  quantities  of  the  white  quartzite  for  this 
purpose,  and  occasionally  a  transparent  piece  of  quartz,  either  white  or 
smoky.  Many  such  objects, — of  the  chase  or  of  war, — made  of  this 
beautiful  material  have  been  found,  and  are  to  be  seen  in  our  museums. 
Within  the  past  10  years,  however,  the  demand  for  these  transparent 
arrow-heads  has  increased,  until  the  demand  has  so  much  exceeded  the 
supply  that  some  of  the  inhabitants,  especially  in  Mitchell  County,  with 
remarkable  cupidity  and  cleverness,  have  chipped  arrow-points  out  of 
quartz  crystals.  These  are  in  many  ways  quite  as  beautiful  as  the  Indian 
work,  but  have  no  archaeological  value,  of  course,  though  they  are  to  some 
extent  sold  as  articles  of  ornament. 

The  highly  modified  crystals  from  White  Plains,  in  Surrey  County, 
and  Stony  Point,  Alexander  Count}',  and  also  from  Catawba  and  Burke 
counties,  N.  C,  are  worthy  of  note  as  being  crystallographically  un- 
equalled anywhere,  and  as  having  formed  the  subject  of  special  memoirs 
by  Dr.  Gerhard  von  Path2  (Pis.  VI,  A  and  VIII,  A).  A  beautiful 
opalescent  quartz  has  been  found  in  Stokes  County. 

Amethyst  (Purple  Variety  of  Quartz.) — An  almost  unique  gem  in  the 
collection  of  the  United  States  National  Museum  at  Washington  is  a 
piece  of  amethyst  found  at  Webster,  N.  C,  and  deposited  by  Dr.  H.  S. 
Lucas.  The  present  form  is  just  such  as  would  be  made  by  a  lapidary  in 
roughly  shaping  a  stone,  preliminary  to  cutting  and  polishing  it.  It  was 
turtle-shaped  when  found,  though  the  shape  was  unfortunately  destroyed 
by  chipping,  and  was  said  to  have  borne  marks  of  the  handiwork  of 
prehistoric  man.  It  now  measures  3f  inches  (6  centimeters)  in  width, 
1-J-  inches  (4  centimeters)  in  thickness,  and  weighs  4f  ounces  (135.5 
grams).  It  is  perfectly  transparent,  slightly  smoky,  and  pale  at  one  end, 
and  also  has  a  smoky  streak  in  the  center. 

2  Naturw.  Verein,  Westphalia,  1888. 
4 


32  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

In  Haywood  County  a  number  of  crystals  of  amethyst  have  been 
secured,  some  of  which  were  cut  into  very  fine  gems. 

In  1894  Mr.  T.  K.  Brunner,  of  Kaleigh,  reported  a  yield  of  amethysts 
from  Catawba,  Macon,  Wake,  Lincoln,  and  other  counties  in  the  State; 
and  in  1898  he  stated  that  large  amethysts  of  good  color  were  still  found 
in  Lincoln  County,  together  with  smoky  and  lighter  colored  varieties. 

In  1901  there  was  a  decidedly  promising  effort  to  prosecute  mining  for 
amethysts  on  a  commercial  scale  at  Tessentee,  on  the  creek  of  that 
name,  in  Smith  Bridge  Township,  Macon  County.  Here  a  large  vein  of 
crystalline  quartz  occurs  in  an  altered  pegmatite.  The  development 
during  the  year  was  entirely  in  a  kaolinized  rock,  in  which  the  amethyst 
crystals,  ranging  from  \  inch  to  3  inches  in  length,  were  found  loose  with 
the  quartz  and  mica  in  the  kaolin.  The  entire  vein  was  exposed  to  the 
depth  of  20  feet  by  a  landslide.  It  would  appear  that  further  working 
should  disclose  the  amethysts  in  the  rock.  The  crystals  are  light  and  dark 
in  color,  and  the  dark  spots  are  often  of  the  deepest  purple.  Xo  finer 
amethysts  have  been  discovered  in  this  country,  and  several  thousand 
dollars  worth  of  crystals  were  sold  as  the  proceeds  of  the  first  development 
work. 

Amethyst  crystals,  often  of  great  beauty  and  of  much  crystallographic 
interest,  have  been  found  in  various  parts  of  the  State,  sometimes  in 
remarkable  quartz  groupings,  such  as  the  so-called  capped  crj'stals,  with 
purple  tops  raised  upon  slender  stilt-like  white  crystals ;  others  with  rare 
faces,  and  then  again  enclosing  water,  especially  from  Lincoln  County 
(see  Pis.  V,  VI,  B,  and  VII,  B). 

Smoky  Quartz. — At  Taylorsville  and  Stony  Point,  North  Carolina,  a 
number  of  clear  pieces  of  this  material  have  been  found  that  cut  fair 
stones  weighing  over  an  ounce  each.  In  Alexander,  Burke,  Catawba,  and 
adjacent  counties,  smoky  quartz  crystals  which  would  afford  fine  gems  are 
frequently  met  with.  They  are  generally  from  1  to  5  inches  in  diameter, 
sometimes  of  a  citron  or  light  yellow  color,  and  often  in  groups  weighing 
up  to  100  pounds  and  over,  quaintly  grouped  and  often  very  clear. 
Crystals  weighing  as  much  as  40  pounds  have  been  taken  from  the  vicinity 
of  Elkin,  in  Surrey  County.  Smoky  and  citrine  quartz  abound  also  in 
Iredell  and  Mitchell  Counties. 

At  Stony  Point,  near  Hiddenite  post-office,  Alexander  County.  X.  C. 
have  been  found  from  time  to  time  in  the  gneissoid  rocks,  pockets  of  quaitz 
crystals  varying  from  absolute  pellucid  and  transparent  to  a  dark  smoky 
color.  These  are  of  wonderful  brilliancy  and  purity,  and  range  from  an 
inch  in  length  to  a  large  size ;  but  they  are  particularly  remarkable  from 
the  fact  that  the  faces  of  the  crystals  are  highly  and  peculiarly  developed, 


N.    C.    GEOLOGICAL    AND    ECONOMIC    SURVEY 


BULLETIN    NO.    12.       PLATE    VI] 


A.     SMOKY     QUARTZ     CRYSTALS,    7/16     NATURAL     SIZE,     HIDDENITE     P.     0.,     ALEXANDER     COUNTY,     N.     C. 


3' 

Q 

2 

o 

2 

H 
ft 

to 

2 

to 


B.     QUARTZ     CRYSTALS,     WITH     AMETHYST     TIPS,     NATURAL     SIZE,     LINCOLN     COUNTY,     N.     C. 


QUARTZ   AND  OPAL.  33 

sometimes  with  great  complexity  (PL  VI,  A).  They  have  furnished  the 
subject  for  several  monographs  on  the  crystallography  of  quartz,  notably 
those  by  Dr.  Gerhard  von  Eath,  of  Bonn,  and  by  Dr.  Gill,  of  Cornell 
University.  Some  of  the  large  complex  groups  are  very  interesting  from 
their  remarkable  twinning-masses  from  150  to  200  pounds,  being  made  up 
of  many  crystalline  faces,  while  in  general  contour  a  single  large  crystal. 
They  stand  quite  unique  as  examples  of  beautiful  color  and  marvelous 
crystallization  (see  Pis.  V  and  VI,  A). 

The  remarkable  smoky  crystals  with  included  cavities,  from  Alexander 
County,  are  referred  to  further  on,  under  quartz  inclusions. 

Hose  Quartz. — Specimens  of  rose  quartz  from  Dan  Eiver,  Stokes 
County,  N.  C,  show  a  beautiful  opalescence,  and  the  existence  of  like 
quartz,  as  well  as  asteriated  quartz,  in  two  other  counties,  Iredell  and 
Cabarrus,  was  determined  in  1894. 

Quartz  Inclusions  (sagenite). — North  Carolina  has  yielded  more  of 
this  material  for  gem  purposes  than  all  other  American  localities  together. 

Eutilated  quartz  of  unexcelled  beauty,  the  rutile  brown,  red,  golden  or 
black,  has  been  brought  to  light  in  many  places  in  Eandolph,  Catawba, 
Burke,  Iredell,  Jackson,  and  Alexander  counties,  especially  the  last,  where 
in  1888  crystals  of  quartz,  3  inches  in  length,  and  filled  with  rutile  the 
thickness  of  a  pin,  were  secured  at  Stony  Point  (PL  V) .  Beautiful  series 
of  these  formerly  in  the  collection  of  J.  W.  Wilcox,  of  Philadelphia,  are 
now  in  the  Morgan-Bement  collection  in  New  York.  In  1901,  fine  ruti- 
lated  quartz,  well  crystallized  and  perfectly  transparent,  was  developed, 
together  with  handsome  garnets,  in  the  monazite  mines  near  Shelby, 
Cleveland  County. 

Hornblende  in  quartz  is  reported  as  found  in  Burke,  Alexander,  and 
Iredell  counties. 

Mining  operations  at  Stony  Point,  N.  C,  have  brought  to  light  a 
number  of  crystals  4  by  3  inches,  and  masses  of  quartz  6  by  3  inches, 
some  of  the  former  filled  with  what  appears  to  be  asbestos  or  byssolite, 
forming  an  interesting  and  attractive  material  susceptible  of  being  cut 
into  charms  and  other  objects.  Magnificent  polished  specimens  are  in 
the  Morgan-Tiffany  and  Morgan-Bement  collections.  The  inclosures  of 
what  is  seemingly  gothite  in  minute  red,  fan-shaped  crystalline  groups 
or  tufts,  form  also  a  beautiful  and  interesting  gem  stone. 

Among  other  inclusions,  some  of  which  might  be  utilized  for  gems, 
the  following  may  be  mentioned  from  North  Carolina  :  Quartz,  including 
scales  of  hematite  from  King's  Mills,  Iredell  County;  quartz  containing 
crystals  of  green  spodumene  (hiddenite)  from  Stony  Point;  inclusions  of 


34  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

muscovite  mica,  that  are  green  when  viewed  through  the  side  of  the  prism, 
and  of  green  chlorite,  from  several  other  localities  in  Alexander  County. 

A  remarkable  specimen  of  this  kind,  that  was  a  "  nine-days  wonder  " 
some  years  ago,  was  the  so-called  Gibsonville  emerald.  This  was  a  stone 
weighing  9  ounces,  plowed  up  near  Gibsonville,  Guilford  County,  which 
was  pronounced  a  genuine  emerald  by  some  local  expert,  who  tested  it, 
and  with  the  microscope  showed  that  it  contained  various  small  diamonds. 
Its  value  was  estimated  up  in  the  thousands,  and  $1000  was  reported  to 
have  been  refused  for  it  by  its  owner,  who,  as  it  was  believed  to  be  the 
largest  known  emerald,  expected  that  it  would  bring  him  a  fortune. 
Being,  therefore,  too  valuable  to  be  be  entrusted  to  an  express  compan}*, 
he  put  himself  to  the  expense  of  a  trip  to  New  York,  where  his  prize 
proved  on  examination  to  be  a  greenish  quartz  crystal,  filled  with  long 
hair  like  crystals  of  green  byssolite  or  actinolite,  on  which  were  series 
and  strings  of  small  liquid-cavities  that,  glistening  in  the  sun,  had  led  to 
the  included  diamond  theory.  The  best  offer  that  he  received  for  the 
stone  was  $5. 

Fluid  Inclusions. — In  March,  1882,  Mr.  William  E.  Hidden  described 
and  illustrated  before  the  New  York  Academy  of  Sciences  some  unpar- 
alleled specimens  obtained  at  Stony  Point,  Alexander  County — the 
emerald  locality  elsewhere  noted.3  Here  some  400  pounds  of  choice  large 
crystals  of  smoky  quartz  were  taken  out  of  a  "  pocket "  in  a  quartz  vein, 
besides  much  of  less  fine  quality.  These  crystals  were  filled  with  cavities 
containing  a  clear  lustrous  fluid,  and  of  extraordinary  size,  those  of  an 
inch  long  being  not  uncommon,  and  some  of  double  that  length.  The 
largest  was  2J  inches  by  J  of  an  inch.  So  abundant  were  they  that  at 
times  the  crystals  seemed  to  be  made  up  of  thin  walls  of  quartz,  separating 
a  multitude  of  elongated  cavities,  parallel  to  the  rhombohedral  or  pris- 
matic faces  of  the  crystals  (PL  VIII,  B). 

It  is  a  matter  of  great  regret  that  such  unique  specimens  could  not 
have  been  studied  with  the  minute  care  given  by  Professors  Dana  and 
Penfield  to  those  of  Branchville,  Conn.  But  now  comes  the  singular 
conclusion  of  this  account.  The  whole  body  of  these  crystals,  carefully 
taken  out  and  put  aside  as  great  treasures,  were  shattered  into  fragments 
in  a  single  night,  by  the  temperature  falling  below  the  freezing  point. 
The  contained  fluid  was  evidently,  as  in  the  Branchville  quartz,  principally 
water,  and  its  expansion  in  freezing  destroyed  the  entire  body  of  speci- 
mens. Those  with  few  cavities  exploded  with  sharp  reports,  and  pieces 
were  blown  as  much  as  15  feet  away.    Those  filled  with  small  cavities  were 

3  On  a  Phenomenal  Pocket  of  Quartz  Crystals  ;  Trans.  N.  Y.  Acad.  Sci.,  March,  1SS2. 


N.    C.    GEOLOGICAL    AND    ECONOMIC    SURVEY 


BULLETIN    NO.    12.       PLATE   VIII 


E 

o 

I 

2 
3 


td 

e 


A.    GROUP    OF    QUARTZ    CRYSTALS,    PARALLEL    CRYSTALLIZATION,     S/%    NATURAL    SIZE,    LINCOLN    CO.,    N.    C. 


GROUP  OF  QUARTZ    CRYSTALS,  ENCLOSING   CLAY   AND   WATER,    $/$    NATURAL   SIZE,   BURKE  COUNTY,    N.    C. 


QUARTZ   AND  OPAL.  35 

reduced  to  little  heaps  of  fragments  frozen  together  in  a  coherent  mass. 
All  that  remained  for  the  illustration  of  Mr.  Hidden's  paper  before  the 
Academy,  were  flakes  of  flat  pieces,  parallel  to  the  faces  of  the  rhombo- 
hedron,  and  filled  and  clouded  with  elongated  and  often  rod-shaped 
cavities,  in  great  numbers  and  of  conspicuous  size. 

So-called  quartz  pseudomorphs  after  calcite  cleavages  occur  at  a  locality 
2  or  3  miles  northeast  from  Eutherfordton,  Eutherford  County,  and 
frequently  contain  irregularly  shaped  cavities  filled  with  water,  which, 
if  broken  out  in  good  shape,  could  be  utilized  as  curious  ornaments.  This 
variety  of  quartz  was  also  found  by  J.  A.  D.  Stephenson  in  Iredell  County. 
This  occurrence  was  named  and  described  by  Mr.  William  E.  Hidden  of 
New  York,  and  shown  to  be  due  simply  to  quartz  filling  irregular  cavities 
between  the  mica  crystals  in  a  pegmatite  rock.  It  is  known  as  "box 
quartz." 

NON-CRYSTALLINE  QUARTZ. 

As  was  stated  above,  these  varieties  have  not  been  very  prominent  in 
North  Carolina. 

Chalcedony. — A  rich  fawn  and  salmon  colored  chalcedony  has  been 
obtained  near  Linville,  in  Burke  County,  and  fine  agates  and  chalcedony  at 
Caldwell's,  Mecklenburg  County,  near  Harrisburg  and  Concord,  Cabarrus 
County,  and  in  Granville  and  Orange  counties,  and  at  some  other  localities 
in  the  State.  A  fine  green-colored  variety  intermixed  with  black  horn- 
blende, that  would  afford  gems  an  inch  across,  was  found  some  years  ago 
in  Macon  County,  and  moss  agate  near  Hillsborough,  in  Orange  County. 

Chrysoprase. — This  valuable  variety  of  chalcedony,  colored  green  by 
oxide  of  nickel,  has  recently  been  found  in  Buncombe  County,  near 
Morgan  Hill,  about  16  miles  from  Asheville.4  It  appears  in  several 
parallel  seams  or  veins,  having  a  general  N.E.-S.W.  course,  and  within 
a  few  feet  of  each  other.  At  the  surface,  the  color  was  pale  green,  but  as 
the  rock  was  opened  down  to  some  4  feet,  the  tint  became  deeper  and 
richer.  Only  a  little  test  work  has  yet  been  done,  and  the  extent  and 
commercial  value  of  the  material  cannot  at  present  be  determined.  The 
stone  polishes  very  well,  and  if  darker  in  color  the  deposit  would  have 
considerable  value. 

Jasper. — In  North  Carolina  fine  jasper,  banded  red  and  black,  is  found 
in  Granville  and  Person  counties ;  bright  brick-red  and  yellow  at  Knapp's, 
Eeed's  Creek,  Madison  County;  at  Warm  Springs;  at  Shut-in-Creek  in 

4Min.  Res.  U.  S.,  1902,  p.  57   (U.  S.  G.  S.  report). 


36 


HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 


Moore  County;  also  in  Wake  County,  and  elsewhere.  Black  jasper 
(basanite)  also  occurs  somewhat,  and  a  beautiful  spear-point,  5  inches 
long,  and  a  number  of  arrow-points,  made  from  this  material,  have  been 
found  near  Statesville. 

OPAL. 

Opal  has  been  found  but  very  sparingly  in  North  Carolina  and,  with 
the  exception  of  the  hyalite  variety,  the  only  specimen  that  has  been  found 
was  near  Asheville,  Buncombe  County,  and  is  of  a  delicate  pink  color. 

Hyalite. — This  mineral  has  been  found  at  the  Culsagee  Mine,  Macon 
County;  the  Carter  Mine,  Madison  County;  near  Concord,  Cabarrus 
County;  in  Burke  County;  and  in  limonite  geodes  found  in  the  decom- 
posed dunite  near  Elf  on  Shooting  Creek,  Clay  County.  Nowhere, 
however,  is  it  of  importance,  though  its  presence  is  of  scientific  interest. 


CHAPTER  VI. 

BEEYL  GEMS  AND  SPODUMENE   (HIDDENITE). 

BERYL  (EMERALD,  AQUAMARINE,  GOLDEN"  BERYL ). 

This  gem,  chemically  a  silicate  of  alumina  and  glucina  (or  beryllia) 
and  ranking  among  the  most  valuable  of  precious  stones,  is  found  quite 
extensively  in  North  Carolina.  Its  commoner  variety,  beryl,  occurs  at 
many  places  in  the  State,  and  sometimes  of  beautiful  gem  quality;  these 
are  the  aquamarines,  blue  to  light  green  and  the  yellow  or  golden  beryl. 
We  will  first  treat  of  the  precious  variety,  emerald. 

Emerald  Beryl. — Very  few  genuine  emeralds  have  been  found  in  the 
United  States;  and  a  number  of  reported  specimens,  assumed  to  be 
such,  have  proved  upon  examination  to  be  only  deep  green  beryls.  The 
true  emerald  owes  its  color  to  a  minute  amount  of  oxide  of  chromium. 
Some  beryls  are  of  a  very  rich  light  green,  and  closely  resemble  emerald, 
so  that  they  may  easily  be  regarded  as  such;  but  they  lack  the  depth  of 
color  so  valued  in  the  real  emerald  (see  Pis.  Ill  and  IX).  The  chief 
localities  are  Alexander  and  Mitchell  counties,  N.  C,  where  emeralds,  or 
beryls  suggesting  them  occur.  In  the  former  it  has  been  found  at  several 
different  points,  with  quartz,  rutile  (some  of  the  finest  known),  dolomite, 
muscovite,  garnet,  apatite,  pyrite,  etc.,  all  in  fine  crystals.  One  of  these 
places,  Stony  Point,  is  about  35  miles  southeast  of  the  Blue  Kidge,  and  16 
miles  northeast  of  Statesville,  N.  C.  The  surface  of  the  country  is  rolling, 
the  altitude  being  about  1000  feet  above  sea  level.  The  soil,  which  is  not 
very  productive,  is  generally  a  red,  gravelly  clay,  resulting  from  the 
decomposition  of  the  gneissoid  rock,  and  under  these  circumstances  it  is 
easy  to  find  the  sources  of  minerals  discovered  on  the  surface.  Prof. 
Washington  C.  Kerr's  theory  of  the  "  frost-drift "  is  well  illustrated  by 
the  conditions  that  prevail  throughout  this  region.  The  unaltered  rock 
appears  at  Stony  Point  at  a  depth  of  26  feet  and  is  unusually  hard, 
especially  the  walls  of  the 'gem-bearing  pockets. 

An  exceptionally  clear  and  reliable  account  of  the  search  for  minerals 
in  Alexander  County  which  resulted  in  the  final  uncovering  of  the  import- 
ant emerald  and  beryl  deposits  of  Stony  Point,  has  been  given  by  the 


38  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

developer  of  the  first  emerald  mine  in  this  country,  William  E.  Hidden/ 
in  1881,  and  we  cannot  do  better  than  quote  his  words.    He  writes : 

Sixteen  years  ago,  the  site  of  the  mine  now  being  worked  was  covered 
with  a  dense  primitive  forest.  Less  than  10  years  ago  (1871),  this  country 
was  mineralogically  a  blank;  nothing  was  known  to  exist  here  having  any 
special  value  or  interest.  Whatever  we  know  of  it  to-day  is  due  directly  or 
indirectly  to  the  earnest  field  work  done  here  in  the  past  7  years  by 
J.  A.  D.  Stephenson,  a  native  of  the  county,  now  a  well-to-do  and  respected 
merchant  of  Statesville,  N.  C.  Under  a  promise  of  reward  for  success,  he 
engaged  the  farmers  for  miles  around  to  search  carefully  over  the  soil  for 
minerals,  Indian  relics,  etc.,  and  for  several  years  he  enjoyed  surprising 
success  in  thus  gathering  specimens.  The  amount  and  the  variety  of  the 
material  gathered  in  this  way  was  simply  astonishing,  and  his  sanguine 
expectations  were  more  than  realized.  To  be  brief  ....  I  will  state  that 
from  a  few  localities  in  the  county  Mr.  Stephenson  would  occasionally  procure 
crystals  of  beryl  of  the  ordinary  kind,  but  now  and  then  a  semi-transparent 
prism  of  beryl,  having  a  decided  grass-green  tint  would  be  brought  to  him. 
These  the  farmers  named  "  green  rocks  "  or  "  bolts,"  and  became  the  principal 
object  of  the  people's  searchings.  Mr.  Stephenson  had  told  them  that  a 
dark  green  beryl  would  be  valuable  if  clear  and  perfect,  would  in  fact  be 
the  emerald  and  for  them  to  search  more  carefully  than  ever  to  find  one. 
Surely,  he  had  informed  the  people  aright  and  had  given  them  a  rara  avis 
to  look  for.  It  is  sufficient  to  say  that  within  a  period  of  about  6  years 
there  was  found  on  3  plantations  in  this  county,  loose  in  the  soil,  a 
number,  say  10,  of  veritable  emeralds,  none  of  which,  however,  were  dark- 
colored  or  transparent  enough  for  use  as  gems.  All  of  these  specimens  went 
into  Mr.  Stephenson's  collection,  with  the  single  exception  of  one  very  choice 
crystal  obtained  at  that  locality  by  the  late  John  T.  Humphreys,  which 
crystal  is  now  in  the  New  York  State  Museum  at  Albany,  after  first  being 
in  the  collection  of  the  late  Dr.  Eddy,  of  Providence. 

The  following  historical  account  is  from  unpublished  notes  on  North 
Carolina  gems,  prepared  for  the  author  hj  Mr.  Stephenson  himself  in 
1888: 

The  first  beryl  I  collected  suitable  for  cutting,  was  found  early  in  1875,  at 
the  locality  now  known  as  the  Emerald  and  Hiddenite  mine.  It  was  a 
beautiful  aquamarine,  but  only  partly  suitable  for  cutting.  A  few  weeks 
later,  I  obtained  at  this  locality  my  first  emerald;  it  was  small  and  rather 
opaque,  but  of  fine  color,  and  the  file-like  markings  on  its  planes  were  very 
distinct.  During  1876,  I  collected  two  others  at  the  same  locality.  .  .  .  Dur- 
ing 1877,  Mr.  I.  W.  Miller  brought  me  2  emeralds  found  on  his  mother's 
farm,  2  miles  northeast  of  the  Emerald  and  Hiddenite  mine.  They  were 
of  good  color  and  quite  transparent,  but  very  rough  on  the  surface.  This 
promising  locality  is  still  undeveloped. 

1  The  Discovery  of  Emeralds  in  North  Carolina,  by  W.  E.  Hidden.  Privately  printed, 
8vo.,  4  p.,  1881,  and  also  Trans.  N.  Y.  Acad.  Sci.,  1882,  pp.  101-105. 


N.    C.    GEOLOGICAL   AND  ECONOMIC    SURVEY 


BULLETIN    NO.    12.      PLATE   IX 


y 


2 


*.-,.. 

* 


1.  BERYL     (EMERALD),    ALEXANDER    COUNTY,    N.     C. 

2.  BERYL    (EMERALD),    STONY    FOINT,    N.    C. 

3.  BERYL,  ALEXANDER    COUNTY,    N.    C. 

4.  BERYL    (EMERALD)    WITH    RUTILE,    ALEXANDER    COUNTV,    N.    C. 

5.  BERYL    CRYSTALS,    GROUP. 

6.  BERYL    (EMERALD)     ON    QUARTZ,    STONY    POINT,    N.    C. 


BERYL   GEMS    AND   SPODUMENE    (  HIDDENITE).  39 

During  ....  1883,  Mr.  J.  O.  Lackey  brought  me  36  small  emeralds,  .... 
found  in  a  vein  of  dark  mica  on  his  farm  a  short  distance  southwest  of 
the  Emerald  and  Hiddenite  mine.  One  or  two  other  occurrences  in  the 
same  region  are  also  reported  in  these  notes. 

In  July,  1880,  Mr.  Hidden  undertook  to  follow  up  the  field-work  of 
Mr.  Stephenson  systematically,  by  engaging  men  to  dig  a  series  of  ditches 
on  a  selected  site,  where  at  least  half  a  dozen  pale  beryls  had  been  uncov- 
ered by  a  farmer  while  plowing.  These  ditches  were  dug  in  different 
directions,  so  as  to  cut  the  strata  of  the  prevailing  country  rock  (gneiss) 
at  various  angles.  After  this  work  had  been  carried  on  for  5  weeks 
without  success,  a  so-called  "  blind  vein  "  or  pocket  was  discovered  at  a 
depth  of  8  feet.  Only  a  few  emeralds,  and  those  of  small  size,  were 
found  in  this  pocket,  but  outnumbering  the  emeralds  50  to  1,  emerald- 
green  spodumene  was  brought  to  light,  which  later  received  the  name  of 
hiddenite  from  Dr.  J.  Lawrence  Smith,  of  Louisville,  Ky.,  who  was  the 
first  to  determine  its  true  chemical  nature  (PI.  III).  By  further  work, 
eleven  other  like  pockets  were  opened  during  the  year,  within  an  area  of 
40  feet  square,  all  carrying  emeralds  in  small  quantities,  and  three 
besides  the  first  containing  hiddenite  or  the  spodumene  emerald  also. 
Other  pockets  were  found  that  yielded  quartz,  rutile,  monazite,  and 
mica  crystals  of  great  beauty.  In  others  the  walls  were  covered  with 
finely  crystallized  dolomite  and  calcite  and  transparent  apatite,  as  well 
as  the  former  minerals. 

The  gem-bearing  "  pockets  "  referred  to  are  expansions  of  quartz  veins 
that  traverse  the  gneiss  rock  of  the  region,  having  generally  an  east  and 
west  course  and  a  dip  toward  the  north.  They  are  usually  quite  narrow, 
but  on  being  followed  downward,  are  found  to  widen  out  occasionally  and 
form  these -cavities,  which  may  be  several  inches  wide  and  a  foot  or  more 
in  length,  or  in  rare  cases  much  larger.  There  are  other  quartz  veins 
also,  of  more  irregular  course,  which  do  not  appear  to  develop  these 
cavities  or  yield  any  of  the  gems.  The  gneiss  rock  decomposes  in  place 
to  a  depth  often  of  many  feet;  and  then  the  quartz  crystals  and  pieces, 
the  mica  and  beryls  or  emeralds,  and  in  short  all  the  harder  minerals  of 
the  veins  and  pockets,  are  left  lying  in  the  soil  formed  by  the  decayed 
and  disintegrated  gneiss.  The  presence  of  these  minerals  on  or  near  the 
surface,  therefore,  serves  to  those  who  understand  their  source,  as  an 
indication  or  "  sign  "  of  the  presence  of  such  veins  in  the  rock  beneath. 
This  was  the  principle,  as  has  been  shown,  that  guided  Mr.  Stephenson 
in  his  pioneer  work. 

In  1881,  a  corporation  called  the  Emerald  and  Hiddenite  Mining  Com- 
pany was  organized  to  work  the  property  at  Stony  Point,  and  prosecuted 


40  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

the  search  for  gems  irregularly,  for  periods  varying  in  length,  for  several 
years.  Since  1885,  however,  but  little  has  been  done,  owing  to  some  legal 
disputes  as  to  the  property. 

The  largest  emerald  crystal  found  during  this  mining  work  was  8-J 
inches  in  length  and  weighed  nearly  9  ounces  (PL  III,  p.  8).  It  is 
now  in  the  Morgan-Bement  collection  at  Xew  York.  This  was  one  of 
nine  crystals  contained  in  a  single  pocket,  all  excellent  in  color  and 
partially  transparent,  but  somewhat  flawed.  One  was  5  inches  in  length 
and  others  were  over  3  inches  (PI.  III). 

One  of  the  most  noteworthy  gems  cut  from  the  product  of  this  mine 
was  from  a  crystal  found  in  a  pocket  at  a  depth  of  over  43  feet.  Its  color 
is  a  pleasing  light  green  and  it  weighs  4  23/32  carats.  In  1887,  at  a 
depth  of  about  70  feet,  another  crystal  was  obtained  that  yielded  a  cut 
stone  of  5  carats.  Both  of  these  are  too  light  in  color  to  rank  as  fine 
gems.  The  two  largest,  and  a  series  of  the  smaller  ones,  went  into  the 
cabinet  of  Clarence  S.  Bement,  now  the  Bement-Morgan  collection  in 
the  American  Museum  of  Natural  History.  Some  fine  ones  are  also  in  the 
British  Museum.  The  rich  emerald  color  in  many  of  these  crystals  is 
confined  to  a  border  from  2/100  to  3/100  of  an  inch  in  thickness 
around  the  edge  and  near  the  termination  of  the  crystals.  If  this  edge 
were  thicker,  fine  gems  could  be  cut  from  it. 

The  value  of  the  emeralds  in  this  deposit  was  relatively  small  com- 
pared with  that  of  the  many  slender  crystals  of  hiddenite.  Both  these 
species  are  in  part  silicates  of  alumina,  but  they  differ  in  the  other  basic 
element  present,  which,  in  hiddenite,  is  lithia,  while  in  the  emerald  it  is 
glucina.  Both  gem  stones  owe  their  color  to  the  same  substance,  oxide 
of  chromium.  The  emeralds  found  in  this  mine  were  very  rarely  without 
flaws,  while  the  hiddenite  was  notably  free  from  such  defects,  and  varied 
in  shade  from  a  yellowish  green  to  the  deepest  blue-green,  often  oddly 
combining  both  extremes  of  color  in  the  same  crystal. 

The  chemical  composition  of  the  emerald  beryl  is  shown  in  the  analysis 
given  below  of  a  leek-green  colored  beryl  from  Alexander  County : 

Analysis  of  Emerald  Beryl.1 

Specific  Gravity,  2.703. 

Constituent.  Per  cent. 

Silica    66.28 

Alumina  18.60 

Ferrous  oxide 0.22 

Beryllia  13.61 

Water 0.83 

Total    99.54 

1  F.  A.  Genth,  Analyst. 


BERYL   GEMS   AND   SPODUMENE    ( HIDDEN ITE )  .  41 

In  the  soil  overlying  the  rock  and  resulting  from  its  decomposition, 
nine  crystals  of  emeralds  were  found,  later,  all  doubly  terminated  and 
measuring  from  1  to  3  inches  (25  to  77  millimeters)  in  width.  The  latter 
crystal  is  very  perfect  as  a  specimen;  it  is  of  fine  light  green  color  and 
weighs  8  J  ounces,  or  only  \  ounce  less  than  the  famous  Duke  of  Devon- 
shire emerald  costal  (PI.  III).  Another  crystal  measuring  2 \  inches 
(63  millimeters)  by  11/12  inch  (25  millimeters)  is  filled  with  large 
rhombohedral  cavities,  formerly  containing  dolomite.  As  mineral  speci- 
mens these  are  quite  unique. 

Some  peculiar  features  pertaining  to  the  emeralds  and  beryls  from  this 
region,  are  particularly  noted  by  Mr.  Hidden.2  "  They  appear,"  he  says, 
"  as  though  filed  across  the  prismatic  faces."  The  basal  plane  is  also  often 
pitted  with  minute  depressed  hexagonal  pyramids,  that  lie  with  their 
edges  parallel  to  one  another,  and  to  the  edge  of  the  di-hexagonal  prism. 
Rarely,  though,  crystals  are  found  with  perfectly  smooth  and  brilliant 
faces.  The  emerald  color  is  often  focused  on  the  surface  and  fades 
gradually  to  a  colorless  central  core,  which  feature  is  of  exceeding  interest 
when  the  genesis  of  the  mineral  is  considered.3  A  similar  etching  or 
corrosion  appears  in  beryls  from  Colorado  and  those  from  Pala,  California. 
A  remarkable  fact  is  that  we  have  here  a  green  beryl  (emerald)  and 
emerald  green  spodumene  (hiddenite),  and  in  the  Pala,  California,  mine, 
we  have  lilac  spodumene  (kunzite)  and  pink  beryls. 

Some  beryls  and  emeralds  of  pale  color  were  also  collected  by  Mr.  J.  A. 
D.  Stephenson,  1  mile  southwest  of  the  Stony  Point  deposit  and  a  short 
distance  from  the  place  where  the  same  mineral  was  found  by  Mr. 
Smeaton,  of  New  York.  Such  discoveries  tend  to  show  that  the  deposit 
is  evidently  not  the  only  one,  and  that  there  is  still  encouragement  for 
future  working  in  this  region. 

In  July,  1894,4  a  new  locality  of  true  emeralds,  in  the  western  part  of 
the  State,  was  discovered  by  Mr.  J.  L.  Rorison,  a  pioneer  miner  of  mica. 
and  Mr.  D.  A.  Bowman,  on  the  Rorison  property,  14  miles  from  Bakers- 
ville,  and  about  the  same  distance  from  Mitchell's  Peak,  Mitchell  County. 
Here,  at  an  elevation  of  5000  feet,  on  Big  Crabtree  Mountain  occurs  a 
vein  of  pegmatite  some  5  feet  wide,  with  well  defined  walls,  in  mica-schist. 
It  outcrops  for  perhaps  100  yards,  with  a  north-and-south  strike  (PI.  X). 
This  vein  carries  a  variety  of  minerals  besides  its  component  quartz  and 
feldspar,  among  these  being  garnets  of  a  translucent  reddish  color,  and 
black  tourmaline,  the  latter  abundant  in  slender  crystals;  beryls,  white, 

2  Am.  Jour.  Sci.,  III,  Vol.  XXXIII,  p.  505,  June,  18S7. 

3  See  Rep.  Dept.  Mining  Statistics,  George  F.  Kunz,  1903. 
4 16th  Ann.  Rep.  U.  S.  Geol.  Sur.,  Part  IV,  p.  600,  1894. 


42  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

yellow,  and  pale  green;  and  the  emeralds.  These  last  are  chiefly  small, 
1  to  10  mm.  wide  by  5  to  25  mm.  long,  but  some  have  been  found  two  or 
three  times  the  size  of  the  largest  above-named.  They  are  perfect  hex- 
agonal prisms,  generally  well  terminated  with  basal  planes,  and  are  of 
good  color,  with  some  promise  for  gems.  They  very  strikingly  resemble 
the  Norwegian  emerald  from  Arendal. 

It  will  be  noticed  that  the  occurrence  here  is  entirely  different  from  that 
in  Alexander  Coiinty,  being  not  in  veins  of  quartz,  but  in  a  pegmatite 
dike.  The  latter  is  the  usual  situation  in  which  beryls  are  found,  from 
New  England  to  the  Carolinas,  and  also  the  large  deposits  of  mica  suitable 
for  mining.  This  emerald  locality  has  been  lately  worked  by  a  New  York 
company,  and,  although  but  few  perfectly  transparent  gems  have  yet  been 
obtained,  a  beautiful  ornamental  stone  has  been  developed.  The  crystals 
vary  from  ■§  of  an  inch  to  1J  inches  in  diameter,  and  are  rarely  over 
1  inch  in  length.  Though  not  clear,  they  have  rather  a  fine  emerald  color, 
and  penetrate  the  quartz  and  feldspar  in  an  irregular  manner.  This  green 
and  white  mixture  is  very  pleasing;  and  as  the  feldspar  has  a  hardness  of 
6.5,  the  quartz  of  7,  and  the  emerald  of  about  8,  the  whole  can  be  cut  and 
polished  together.  Pieces  are  cut  en  caboclion,  showing  sections  of  one  or 
more  emerald  crystals  on  the  top  and  sides  of  the  polished  stone.  The 
name  of  "  emerald  matrix  "  is  given  to  this  ornamental  gem  material  (see 
illustration  in  Morgan-Tiffany  collection)  (see  PL  III).  This  property, 
which  was  worked  quite  extensively  in  1906  by  the  American  Gem  and 
Pearl  Company,  of  New  York,  produced  some  perfectly  transparent  crys- 
tals of  emerald  which  cut  good  gems  up  to  f  carat  in  weight. 

Far  to  the  southwest  of  Stony  Point  and  some  50  miles  south  of  the 
emerald  locality  near  Bakersville,  a  second  new  occurrence  was  noted  in 
1897  by  Mr.  J.  Meyer  of  Charlotte,  N.  C,  who  had  found  near  Earle's 
Station,  in  that  State,  between  Blacksburg,  S.  C,  and  Shelby,  N.  C,  a 
broken  fragment  of  emerald  of  good  color,  better  than  anything  observed 
from  North  Carolina,  although  somewhat  flawed ;  it  was  cut  into  a  facetted 
stone,  of  tapeziform,  or  sub-triangular  shape,  weighing  4  15/16  carats, 
that  quite  closely  resembles  the  material  from  the  Muzo  mine  of  Colombia. 

Aquamarine,  Yellow  and.  Golden  Beryl. — This  mineral,  as  above  stated, 
is  found  at  many  localities  in  North  Carolina,  and  sometimes  of  quality 
fine  enough  to  yield  choice  gems.  It  will  be  noted  that  beryl  localities  are 
met  with  on  both  sides  of  the  Blue  Eidge,  both  in  the  Piedmont  region; 
and  west  of  the  mountains.  Here  again,  for  the  development  of  these 
and  many  other  forms  of  mineral  wealth  in  North  Carolina,  in  the  years 
following  the  devastation  of  the  Civil  War,  a  lasting  debt  of  honor  is 
due  to  Mr.  J.  Adlai  D.  Stephenson,  of  Statesville,  and  also  to  the  late  G-en. 


N.    C.    GEOLOGICAL    AND   ECONOMIC    SURVEY 


BULLETIN    NO.    12.       PLATE    X 


BERYL    GEMS   AND    SPODUMENE    (HIDDENITE).  4  3 

Thomas  L.  Clingman,  who  after  serving  as  a  brave  officer  in  the  Southern 
army,  turned  his  energies  to  the  cultivation  of  the  arts  of  peace  and  the 
improvement  of  the  natural  resources  of  his  State  (see  Pis.  Ill,  IX,  and 
XI). 

Mr.  Stephenson  published  accounts  from  time  to  time  of  his  researches 
and  discoveries,  beginning  soon  after  the  war,  and  continuing  for  a 
number  of  years.  A  number  of  beryl  localities  are  noted  by  Mr.  Stephen- 
son in  the  counties  of  Alexander,  Burke,  Caldwell,  Cleveland,  Macon, 
Mitchell,  and  Yancey,  some  of  them  yielding  choice  material  (PL  IX). 
The  remarkable  discovery  of  emerald  beryls  at  Stony  Point,  Alexander 
County,  has  been  already  described  under  emerald ;  but  there  are  numer- 
ous occurrences  of  beryl  in  the  State,  closely  resembling  those  of  New 
England,  both  in  size  and  variety.  Mr.  Stephenson  called  the  attention  of 
the  author  to  a  dark  green  beryl,  weighing  25.4  ounces,  part  of  which 
would  furnish  gems  of  some  size,  that  was  found  in  January,  1888,  near 
Russell  Gap  Eoad,  Alexander  County,  by  a  farmer  plowing.  This 
locality,  about  10  miles  from  Stony  Point,  is  the  largest  beryl  deposit 
affording  gems  that  has  been  opened  in  North  Carolina.  It  is  noteworthy 
that  the  highly  modified  beryls  of  this  region  occur  rarely,  and  only  when 
associated  with  spodumene  or  albite,  and  also  that  the  white  or  pale  green- 
ish beryls  are  found  with  the  deepest  green  spodumene.  It  has  be- 
fore been  noted  that  the  quartz  and  beryl  of  Alexander  County  are  more 
highly  modified  when  implanted  on  the  feldspathic  layers  of  the  walls  of 
the  pockets.  We  have  here  a  green  spodumene  and  a  green  beryl  (em- 
erald) ;  we  have  the  same  minerals,  rose  or  lilac  colored  (kunzite)  and 
rose  beryl,  at  Pala,  California.  Two  emerald  beryls  found  in  1881,  at  a 
depth  of  34  feet,  were  in  a  little  cavity,  the  walls  of  which  were  almost 
covered  with  crystals  of  albite  twinned  parallel  to  the  base.  Only  four 
emeralds  were  found,  averaging  about  1  cm.  in  the  three  dimensions. 
The  pocket  was  free  from  all  decomposition  whatever.  The  crystals 
were  of  good  color,  transparent,  and  had  their  commoner  planes  well 
polished,  but  they  differed  to  some  extent  in  habit. 

Some  of  the  North  Carolina  beryls,  especially  the  fibrous,  green,  opaque 
beryl  from  Alexander  County,  would  furnish  cat's-eyes,  although  not  very 
fine. 

A  rich  yellow  crystal  was  reported  in  1888  by  Mr.  Stephenson,  as  found 
in  a  quartz  boulder,  with  finely  crystallized  tourmaline,  near  Little  Eiver 
Church,  Alexander  County.  Beryl,  resembling  the  Siberian,  occurs  in 
greenish-yellow  and  deep  green  crystals,  in  the  South  Mountains,  9 
miles  southwest  of  Morganton,  Burke  County;  also  in  the  Sugar  Moun- 
tains at  Shoup's  Ford,  Dietz's,  Huffman's,  and  Hildebrand's.     A  rich 


44  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

blue-green  crystal  in  quartz  was  found  at  Mill's  gold  mine,  Burke  County, 
and  a  fine  transparent  green  crystal  from  that  vicinity  is  now  in  the 
cabinet  of  M.  T.  Lynde,  of  Brooklyn,  1ST.  Y.  Another  Piedmont  locality 
is  at  Wells,  in  Gaston  County. 

Some  of  the  beryls  from  the  neighborhood  of  Statesville  are  of  unusual 
interest  from  their  crystalline  forms;  these  have  been  described  and  in 
part  figured  by  Mr.  W.  E.  Hidden.5 

Passing  to  the  counties  west  of  the  Blue  Eidge,  several  good  localities 
are  known  where  fine  beryls  occur,  generally  in  pegmatite  dikes,  like  the 
Bakersville  emeralds.  Clear  green  beryls  have  also  been  obtained  at 
Balsam  Gap,  Buncombe  County;  Carter's  mine,  Madison  County;  Thorn 
Mountain,  Macon  County,  and  at  one  or  two  points  in  Jackson  County. 
The  following,  however,  are  more  important: 

Blue  beryl  in  fine  crystals  that  afforded  fair  gems  was  found  near  the 
Yancey  County  line,  and  golden  beryl  in  the  same  vicinity,  as  noted  by 
Dr.  Pratt.  Some  crystals  2  feet  long  and  7  inches  in  diameter,  with  small 
clear  spots,  which  would  cut  into  gems,  occur  4  miles  south  of  Bakers- 
ville, and  near  Grassy  Creek,  both  in  Mitchell  County  (PI.  III).  Fine 
blue-green  aquamarine  is  known  at  Pay's  mica  mine  on  Hurricane  Mt., 
Yancey  County. 

The  Grassy  Creek  locality,  just  noticed,  has  attracted  some  attention 
recently  as  a  source  of  fine  aquamarine.  It  is  situated  on  Brush  Creek 
Mountain,  Estatoe  P.  O.,6  Mitchell  County.  The  beryls  occur  in  a 
pegmatite  dike  that  cuts  across  the  country  rock  (gneiss)  at  a  low  angle, 
instead  of  conforming  to  the  steep  lamination  of  the  latter,  as  do  the 
ordinary  mica  veins.  These  last  are  chiefly  muscovite,  while  the  dike 
consists  of  quartz  and  albite,  with  black  mica  (biotite),  garnet,  black 
tourmaline,  titanic  iron  and  beryls.  Most  of  the  latter  are  opaque  and 
yellowish,  the  bright  green  ones  being  only  occasionally  found,  and  not 
always  in  the  dike,  but  sometimes  in  the  adjacent  mica-schist, — as  though 
a  product  of  contact  alteration.  The  best  crystals  have  a  fine  aquamarine 
tint,  and  some  have  yielded  very  perfect  gems  of  more  than  a  carat  in 
weight.  Some  honey-yellow  beryls  also  occur,  sufficiently  clear  for  cutting, 
but  these  are  rare. 

Another  locality  in  Mitchell  County,  very  promising  as  a  source  of 
aquamarines,  is  the  Wiseman  mine  at  Elatrock,  near  Spruce  Pine  P.  0. 
Here  the  beryls  occur  not  in  a  dike,  as  in  the  last  instance,  but  in  con- 
nection with  veins  of  muscovite  mica  that  run  with  the  gneiss  rock. 

5  Am.  Jour.  Sci.,  Vol.  XXII,  August,  1881. 

6  J.  H.  Pratt.     Jour.  Elisha  Mitchell  Sci.  Society,  Vol.  XIV,  Part  2,  1897,  p.  80. 


N.    C.   GEOLOGICAL   AND   ECONOMIC    SURVEY 


BULLETIN    NO.    12.       PLATE    XI 


BERYL    CRYSTALS,     GROUP,     NATURAL    SIZE,    BURNSVILLE,     N.     C. 


BERYL    GEMS    AND    SPODUMENE    (HIDDENITE).  45 

Several  colors  are  found  here ;  some  are  of  fine  aquamarine  tint,  and  have 
yielded  very  perfect  gems  of  more  than  a  carat;  less  frequently  they  are 
honey-yellow,  with  portions  clear  enough  to  be  cut;  while  rich  blue  ones, 
equal  to  any  of  those  from  Brazil,  have  also  been  obtained  in  the  course 
of  the  past  15  years,  first  by  desultory  working  and  then  by  the  most 
systematic  operations  under  the  American  Gem  Company,  of  New  York 
City.  Large  quantities, — thousands  even, — of  magnificent  blue  gems 
weighing  from  1  to  20  carats,  have  been  taken  out  here.     (See  PL  II.) 

At  the  Littlefield  mine,  on  Tessentee  Creek,  Macon  County,  clear  aqua- 
marines have  been  obtained  which  have  cut  into  beautiful  gems. 

At  the  Charleston  Exposition  of  1901,7  Dr.  J.  H.  Pratt  exhibited, 
among  other  choice  minerals  of  North  Carolina,  a  crystal  of  golden  beryl 
1J  inches  in  diameter  and  %\  inches  long,  obtained  from  an  Indian  mound 
near  Tessentee  Creek,  not  far  from  the  Littlefield  mine,  and  hence  pre- 
sumably from  that  locality.  This  is  the  first  instance  recorded  of  a  beryl 
crystal  found  deposited  in  an  Indian  grave. 

Another  important  locality  in  Macon  County  is  the  McG-ee  mine.  Here 
the  gems  are  sea-green  and  occasionally  yellow,  and  are  found  in  quantity. 

A  fine  representation  of  the  North  Carolina  beryl  is  to  be  seen  in  the 
museum  of  the  State  University  at  Chapel  Hill,  together  with  the  other 
minerals  of  the  State,  collected  by  the  late  Mr.  Stephenson,  in  the  course 
of  his  enthusiastic  explorations,  and  whose  cabinet  was  most  appropriately 
secured  by  the  State. 

HIDDENITE   OR  LITHIA   EMERALD. 

This  is  a  stone  which  is  peculiar  to  North  Carolina,  and  hence  possesses 
especial  interest  in  any  account  of  the  minerals  of  that  State.  The 
circumstances  under  which  it  first  came  into  notice  have  already  been 
mentioned  under  Emerald,  with  which  it  was  found,  at  Stony  Point, 
Alexander  County,  in  about  1879.  Mineralogically,  it  is  a  variety  of 
spodumene,  a  well-known  silicate  of  alumina  and  lithia,  usually  found  in 
large  rather  coarse  crystals,  opaque  and  of  no  beauty.  Occasionally,  how- 
ever, it  is  transparent  and  richly  colored  (PI.  III).  The  first  occurrence 
of  this  form  of  it  in  the  United  States,  was  in  these  small  brilliant,  green 
crystals  in  North  Carolina;  a  second  has  lately  attracted  much  attention 
in  San  Diego  County,  California,  where  the  crystals  are  large  and  of  a 
rose-lilac  tint ;  this  variety  is  the  new  gem-stone  called  kunzite. 
The  history  of  the  North  Carolina  discovery  is  as  follows : 
About  1879,  some  crystals  of  a  yellow  and  yellowish-green  mineral, 

7  Report  Dept.  Mining,  Charleston  Exposition,  1901. 


46  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH   CAROLINA. 

supposed  to  be  diopside,  were  found  at  Stony  Point,  Alexander  County, 
N.  C,  associated  with  beryl,  quartz,  rutile,  garnet,  dolomite,  etc.  These 
crystals  soon  came  into  the  hands  of  J.  A.  D.  Stephenson  of  Statesville, 
Who  sent  the  best  of  them  to  Norman  Spang,  of  Pittsburg,  Pa.,  a  noted 
collector  of  choice  minerals.  About  2  years  later  Mr.  Stephenson  called 
the  attention  of  William  E.  Hidden  to  this  mineral,  and  to  the  locality; 
Mr.  Hidden  then  sent  specimens  for  examination  to  Dr.  J.  Lawrence 
Smith,  of  Louisville,  Ky.,  who  found,  on  investigation,  that  the  mineral 
was  not  diopside  but  a  transparent  variety  of  spodumene.  The  crystals 
were  first  found  loose  in  the  soil  with  emeralds,  but  systematic  mining 
revealed  them  attached  to  the  veins  of  the  wall-rock  (PL  XII,  A).  The 
spodumene  is  generally  more  or  less  altered,  hence  its  pitted  or  eaten-out 
appearance ;  but  when  found  in  the  rock,  the  crystals  are  quite  perfect  and 
unchanged.  They  are  all  transparent  and  range  from  colorless  (rare), 
to  a  light  yellow,  into  yellowish-green,  then  into  deep  yellow  emerald- 
green.  Sometimes  an  entire  crystal  has  a  uniform  green  color,  but 
generally  one  end  is  yellow  and  the  other  green.  Its  hardness  is  on 
the  prism  faces,  6.5,  and  across  them,  according  to  Doctor  Smith,  nearly 
that  of  the  emerald ;  but  a  series  of  experiments  proved  it  to  be  some- 
what less.  At  first  considerable  difficulty  was  experienced  in  cutting  it, 
owing  to  its  remarkably  perfect  prismatic  cleavage,  which  is  very  lustrous. 
Gems  have,  however,  been  cut  up  to  2 -J  carats  in  weight.  Specific  gravity, 
3.18  to  3.194. 

Specimens  of  the  crystals  and  of  cut  stones,  have  gone  into  all  important 
public  and  private  collections  in  the  United  States,  and  to  some  extent 
abroad.  Dr.  Spencer,  of  the  British  Museum,  has  recently  described 
several  specimens  there  contained,  in  a  report  to  the  Director,  Dr. 
Fletcher,  as  follows: 

Hiddenite:     Alexander  County,  N.  C. 

A  faceted  stone  of  a  rich  emerald-green  color,  perfectly  transparent,  and 
with  only  1  or  2  small  cracks.     Weight,  0.494  gram. 

A  piece  of  matrix  bearing  2  or  3  small  crystals.  Also  numerous  isolated 
prismatic  crystals  up  to  2V2  centimeters  in  length;  many  rather  pale  in  color, 
but  3  crystals,  presented  by  Mr.  Hidden,  in  1893,  of  a  rich  emerald-green. 

The  yellow  tinge  exhibited  by  this  mineral  in  even  the  darkest  green 
gems  will  prevent  it  from  competing  with  the  emerald,  since  it  is  this 
very  quality  that  has  kept  down  the  prices  of  the  Siberian  demantoids, 
or  Uralian  emeralds,  as  the  green  garnets  are  variously  termed.  The 
finest  crystal  of  lithia  emerald  ever  found  is  in  the  Morgan-Bement 
collection  at  New  York.     (See  PI.  III.)     It  measures  2f  inches   (68 


BERYL   GEMS   AND    SPODUMENE    (HIDDENITE).  47 

millimeters)  by  J  inch  (14  millimeters)  by  i  inch  (8  milli- 
meters). One  end  is  of  very  fine  color,  and  would  afford  the  largest  gem 
yet  cut  from  this  mineral,  weighing  perhaps  5J  carats.  In  Dr.  Augustus 
C.  Hamlin's  cabinet  is  a  fine  gem  weighing  about  2  carats;  and  a  cut 
stone  of  fine  color,  and  a  good  crystal  are  in  the  collection  of  Col.  W.  A. 
Eoebling.  Dr.  J.  Lawrence  Smith 8  says  that  the  crystals,  when  cut  and 
polished,  resemble  the  emerald  in  luster  though  the  color  is  not  so  intense 
as  in  the  finer  varieties  of  the  latter  gem.  Prof.  Edward  S.  Dana  says 
that,  owing  to  its  dichroism,  it  has  a  peculiar  brilliancy  which  is  wanting 
in  the  true  emerald.  Thomas  T.  Bouve,  of  Boston,  says :  "  One  might 
infer  from  the  statement  .made  of  the  great  brilliancy  of  both  the  hiddenite 
and  garnet,  when  compared  with  the  emerald,  that  this  should  decide 
their  relative  beauty;  but  it  is  not  the  case,  for  the  emerald  has  a  beauty 
of  its  own,  in  its  deep  and  rich  shade  of  color,  that  will  ever  make  it  rank 
at  least  an  equal  in  loveliness  with  the  newer  aspirants  for  favor." l 
When  the  hiddenite  was  first  introduced,  it  had  a  considerable  sale  because 
of  its  novelty  as  an  American  gem  and  because  of  the  newspaper  notoriety 
it  gained  through  the  controversy  that  arose  as  to  its  discovery.  Hence 
for  a  time  the  demand  exceeded  the  supply,  which,  from  the  desultory 
working  of  the  mine,  was  limited.  Thus  a  2-J  carat  stone  was  sold  for 
$500.00,  and  a  number  of  stones  brought  from  $40.00  to  over  $100.00  a 
carat.  The  total  sale  of  all  the  gems  found,  from  the  beginning  of  oper- 
ations in  August,  1880,  to  the  close  of  1888,  amounted  to  about  $7500.00, 
the  yield  in  1882,  during  which  the  preparatory  work  was  done,  being 
about  $2000.00.  At  the  time  of  the  discovery,  this  was  supposed  to  be 
the  first  occurrence  of  transparent  spodumene;  but  Pisani,  in  the  Comptes 
Eendus  for  1877,  announced  a  transparent  yellow  spodumene  that  had 
been  found  at  Minas  G-eraes,  Brazil,  where  it  exists  in  large  quantities 
and  has  been  extensively  sold  as  chrysoberyl.  The  writer  saw  nearly  a  ton 
of  broken  crystals  of  this  mineral  at  Idar,  Germany,  in  1881,  whither  it 
had  been  sent  for  cutting.  A  stone  from  Brazil  weighing  1  carat  is 
in  the  United  States  National  Museum.,  as  also  a  series  of  crystals  and 
cut  stones  from  North  Carolina.  At  Branchville,  Conn.,  spodumene  is 
found  in  opaque  crystals  4  or  5  feet  long  and  a  foot  in  diameter,  almost 
entirely  altered  to  other  minerals.  In  spots,  however,  it  is  transparent 
enough  to  furnish  small  gems  of  an  amethystine  color.  The  alterations 
which  have  taken  place  have  entirely  changed  it  to  what  might  almost  be 
called  a  defunct  gem;  otherwise,  these  crystals  would  have  afforded  gems 

8  Am.   Jour.   Sci.,   Ill,   Vol.   XXI,   p.   128,  Feb.,   1881. 
8Proc.  Boston  Soc.  Nat.  His.,  Vol.  XXIII,  p.  2,  Jan.  2,  1884. 
5 


48  HISTORY  OF  THE  GEMS  FOUND  IN  NOPcTH  CAROLINA. 

over  an  inch  in  thickness  and  several  inches  in  length.  The  color  before 
the  alteration  was  probably  much  richer  pink.  It  is  of  mineralogical 
value  only. 

Within  the  past  year,  the  discoveries  in  San  Diego  County,  California, 
have  brought  to  light  spodumene  of  "a  similar  color  with  the  little  rem- 
nants at  Branchville,  but  entirely  clear  and  unaltered. 

The  North  Carolina  mineral  was  given  its  name  by  Dr.  J.  Lawrence 
Smith  (who  first  determined  its  true  character)  in  honor  of  Mr.  W.  E. 
Hidden.  The  crystals  are  slightly  inclined  prisms  in  form,  ranging  from 
quite  small  up  to  perhaps  2  inches  in  length  and  from  -J  to  \  of  an  inch 
in  diameter,  for  the  largest.  The  first  crystal  of  any  size  that  was  found, 
was  shown  in  the  remarkable  North  Carolina  gem-exhibit  at  the  Charles- 
ton Exposition  of  1901-02.  Notwithstanding  the  interest  which  attaches 
to  this  peculiar  and  beautiful  American  gem,  no  further  developments  of 
it  have  been  made  for  several  years,  owing  to  the  mines  at  Stony  Point 
being  closed  under  litigation. 

The  chemical  composition  of  hiddenite  is  given  in  the  following  table 
of  analyses : 

Analyses  of  Hiddenite. 
Specific  Gravity,  3.152-3.189. 


Constituent. 

Silica 

Alumina   

P*er  cent.1 

63.95 

26.58 

Per  cent 
64.35 

28.10 

Ferric  Oxide   

0.25 

Chromic  Oxide 

Ferrous  Oxide 

0.18 

1.11 

Lithia    

Soda    

6.82 

1.54 

7.05 
0.50 

Potassa     

0.07 

Water    

0.15 

1  F.  A.  Genth,  analyst.  Am.  Jour.  Sci..  Ill,  23.  68. 

2  ,T.  Lawrence   Smith,   analyst,   Am.   .Tour.   Sci.,   Ill,   21,   128. 


N.    C.    GEOLOGICAL   AND  ECONOMIC   SURVEY 


BULLETIN    NO.    12.      PLATE   XII 


A.     SPODUMENE     (HIDDENITE)     IN     MATRIX,     NATURAL     SIZE,     STONY     POINT,     N.     C. 


3.     CYANITE,      NATURAL     SIZE,     BURXSVILLE,      N.     C. 


CHAPTER  VII. 

GARNET,  ZIRCON,  RUTILE,  AND  OCTAHEDRITE. 

GARNET. 

The  name  garnet  is  applied  not  to  any  single  mineral,  but  to  a  well- 
marked  little  group,  comprising  several  species  and  varieties,  differing 
in  color  and  chemical  composition,  but  very  closely  related  physically. 
They  all  crystallize  in  the  isometric  system,  and  are  all  constructed  on  the 
same  type  chemically,  though  varying  considerably  in  their  components. 
They  are  silicates  of  lime,  magnesium,  iron,  or  manganese,  with  more  or 
less  of  alumina,  ferric  iron  or  chromium.  According  to  the  presence  and 
the  proportions  of  these  substances,  the  species  and  varieties  are  deter- 
mined. Several  members  of  the  garnet  group  are  found  in  North 
Carolina,  some  of  the  commoner  kinds  in  large  quantities,  so  that  they 
have  been  mined  for  use  as  an  abrasive  and  some  of  choicer  quality  that 
yield  beautiful  gems. 

Of  the  latter  are  to  be  noted  the  following:  Almandine  or  precious 
garnet,  the  iron-alumina  variety;  pyrope  or  Bohemian  garnet,  the  mag- 
nesia-alumina variety;  rhodolite,  a  peculiar  and  beautiful  garnet  inter- 
mediate between  these  two ;  and  spessartite,  or  manganese-alumina  garnet. 
This  last  is  rare  and  the  only  North  Carolina  occurrence  of  it  is  reported 
by  Dr.  J.  H.  Pratt,  in  beautiful  flattened  plate-like  crystals  in  mica,  near 
Bakersville,  some  large  enough  to  cut  gems  of  a  carat  or  more.1  Very 
elegant  crystals  of  large  size  have  been  found  at  Amelia  Court  House, 
Virginia,  in  an  albite  pegmatite.  This  variety  is  not  red,  but  of  a  peculiar 
rich  brown  or  fulvous  tint  (PI.  XIII). 

Almandite  is  the  most  frequent  variety,  and  the  one  that  has  been  mined 
for  garnet  paper  and  other  abrasive  purposes,  including  a  so-called 
"  emery,"  for  which  tons  of  it  have  been  crushed.  The  color  is  red,  of 
many  shades,  varying  to  brownish  and  purplish  reds.  The  peculiar  play 
of  color  observed  in  some  of  the  North  Carolina  garnets  is  usually  due 
to  inclusions.  In  Burke,  Caldwell,  and  Catawba  counties  are  found 
large  dodecahedral  and  trapezohedral  almandite  crystals  coated  externally 
with  a  brown  crust  of  limonite,  the  result  of  superficial  alteration,  but 

1  Gems  and  Precious  Stones  of  North  America,  New  York,   1S00.   pp.   70-S.'?. 


50  HISTORY  OF  THE  GEMS  FOUND  IN"  NORTH  CAROLINA. 

usually  showing  a  bright  and  compact  interior  when  broken.  They  are 
sometimes  as  fine  in  color  as  the  Bohemian  garnets,  and  should  find  a 
ready  use  for  watch-jewels  and  other  like  purposes.  Some  crystals  have 
been  found  weighing  20  pounds  each.  Although  not  fine  enough  for 
gems,  these  might  be  cut  into  dishes  or  cups  measuring  from  3  to  6 
inches  across,  as  has  been  done  in  India.  A  very  large  quantity  of  these 
garnets  has  been  found  about  8  miles  southeast  of  Morganton,  and  also 
near  Warlick,  in  Burke  County.  Here  they  have  been  extensively  mined 
for  abrasive  use  and  also  near  HalFs  Station  in  Jackson  County,  where 
garnet  wheels  are  manufactured. 

Bohemian  or  pyrope  garnets. — This  garnet  of  good  color,  that  has  fur- 
nished gems,  has  been  found  in  the  sands  of  the  gold-washings  of  Burke, 
McDowell,  and  Alexander  counties.     This  species  has  a  more  blood  red 


N 


tint  than  the  preceding,  and  is  used  largely  in  the  garnet  jewelry  made 
in  Bohemia,  whence  the  name;  it  is  the  same  also  that  passes  under  the 
name  of  Cape  ruby,  from  South  Africa,  and  Arizona  ruby,  from  the 
territory  of  that  name. 

Rhodolite. — This  is  by  far  the  most  important  variety  of  garnet  in 
North  Carolina,  and  is  found  nowhere  else,  indeed,  so  that  it  possesses 
peculiar  interest.  Since  it  has  been  recognized  and  developed,  it  has 
proved  to  be  also  the  most  valuable  gem  produced  commercially  in  the 
State.  The  locality  is  much  the  same  as  that  of  the  Cowee  rubies,  in 
Macon  County,  in  the  gravels  of  streams  heading  on  Mason;s  Mountain, 
and  on  the  mountain  itself  at  some  points.  When  first  observed  it  was 
regarded  as  a  very  beautiful  and  brilliant  light-colored  form  of  almandine ; 
but  analysis  subsequently  showed  that  it  is  a  variety  intermediate  between 
that  and  pyrope,  in  fact  an  inter-mixture  of  the  two,  in  the  proportion  of 
f  pyrope  and  -J  almandine. 

The  first  mention  of  these  Macon  County  garnets  was  apparently  due 
to  Mr.  A.  M.  Field,  of  Asheville,  in  1893,2  and  was  made  by  the  author 
in  his  report  on  the  production  of  precious  stones  for  that  year,  and 
again  in  1897.3  In  the  following  year,  a  paper  was  published  by  Mr.  W. 
E.  Hidden  and  Dr.  J.  H.  Pratt,  in  which  the  whole  subject  was  treated 
fully,  the  analyses  described,  the  nature  of  the  stone  determined,  and  the 
name  of  rhodolite  proposed  for  it  as  a  new  variety.4  This  name  is  from 
the  Greek  word  rhodon,  a  rose,  from  the  resemblance  of  its  color  to  some 
kind  of  roses  and  rhododendrons.  The  mineral  shows  a  light  shade  of 
fine  red,  without  the  dark  aspect  that  belongs  to  most  garnets,  and  it 

2Min.  Res.  U.  S.,  1893   (Rep.  U.  S.  Geol.  Survey),  pp.  15  and  19. 

3Min.  Res.  TJ.  S.,  1897   (Rep.  U.  S.  Geol.   Survey),  p.  13. 

4  Am.  Jour.  Sci.,  IV,  Vol.  V,  1898,  pp.  293-296  ;  and  also  Vol.  VI,  pp.  463-46S. 


Plate  No 


B 
Cyan  ile, 

Seven  .Mile  Ridge,  Mitchell  County, 
North  Carolina. 


A 

Cyan  He, 

Seven  Mile  Ridge,  Mitchell  County, 
North  Carolina. 


© 


c 
Rhodolite. 

Cowee  Valley, 

Macon  Couniv.  North  Carolina, 


D 
Rhodolite. 

<v  Valley, 
Macor.  Couniv.  North 


i  hvl'almi  PrrtnoArt  Cc 


•  ■    d 


II 

GARNET,  ZIRCON,  RUTILE,  AND  OCTAIIEDRITE.  51 

a 

possesses  a  remarkable  degree  of  brilliancy,  especially  in  artificial  light. 
Those  qualities  give  it  great  value  for  gem  purposes,  and  it  has  become 
very  popular.  The  pieces  found  are  not  generally  large,  but  stones  have 
been  cut  of  as  much  as  14  carats.  A  very  fine  exhibit  of  rhodolites  was 
made  in  the  State  Geological  Survey  Exhibit  at  the  recent  Expositions  at 
Buffalo,  Charleston,  and  St.  Louis.  They  have  been  developed  by  two 
companies  with  remarkable  success;  and  apparently  more  gems  in  value 
have  been  sold  from  this  mine  than  from  all  other  sources  in  the  State 
combined.     (See  PL  XIII.) 

Perhaps  $53,000  worth  of  these  stones  have  been  sold  from  these 
mines  to  date. 

ZIRCON. 

Zircon  (silicate  of  zirconia)  is  a  mineral  of  somewhat  wide  distribu- 
tion, though  rarely  conspicuous.  It  crystallizes  in  square  prisms  with 
pyramidal  terminations,  generally  opaque  and  of  some  shade  of  brown. 
When  transparent,  and  of  any  size,  beautiful  gems  can  be  cut  from 
zircon  crystals ;  these  are  the  hyacinths  of  jewelers. 

In  North  Carolina  zircon  is  abundant  in  the  gold  sands  of  Polk,  Burke, 
McDowell,  Eutherford,  a'nd  Caldwell  counties,  and  in  nearly  all  the 
colors  found  in  Ceylon — yellowish-brown,  brownish- white,  amethystine, 
pink,  and  blue.  The  crystals  are  beautifully  modified,  but  too  minute 
to  be  of  value.  Brown  and  brownish-yellow  crystals,  very  perfect  in  form, 
occur  abundantly  in  Henderson  County,  N.  C,  and  in  equal  abundance 
in  Anderson  County,  S.  C.  The  latter  are  readily  distinguished  from  the 
North  Carolina  crystals,  as  they  are  generally  larger,  often  an  inch  across, 
and  the  prism  is  almost  always  very  small,  the  crystal  frequently  being- 
made  up  of  the  two  pyramids  only.  They  are  found  in  large  quantities, 
loose  in  the  soil,  as  the  result  of  the  decomposition  of  a  feldspathic  rock. 
Large  and  richly  colored  zircons,  sometimes  as  much  as  2  ounces  in 
weight,  and  of  fine  shades  of  brown  and  hone}^-red,  are  found  in  Iredell 
County.5. 

Within  the  past  20  years  some  demand  has  arisen  and  continued  for 
minerals  containing  the  rare  earths, — zirconia,  thoria,  etc., — as  these 
substances  are  used  for  the  mantles  or  hoods  of  the  Welsbach  and  other 
forms  of  incandescent  gas  burners.  This  demand  led  to  active  search 
throughout  the  world  for  the  minerals  containing  these  oxides,  and  so 
successful  has  been  this  search  that  many  species  which  were  once  con- 
sidered rare  are  now  so  plentiful  that  they  are  quoted  at  one-tenth  to  one- 

5  N.  C.  Geolog.  Survey,  Economic  Paper,  No.  6,  1901,  p.  99;  and  Department  of 
Mining  Statistics,  1898,  p.  34. 


52  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

hundredth  of  their  former  prices.  The  best  zircon  localities  in  Xorth 
Carolina  are  on  the  Old  Meredith  Freeman  estate,  and  the  Jones  estate, 
Green  Kiver,  Henderson  County.  It  was  leased  for  25  years  by  Gen. 
Thomas  L.  Clingman,  who,  as  early  as  1869,  mined  1000  pounds  of  zircon, 
and  during  that  whole  period  never  lost  faith  in  the  incandescent  proper- 
ties of  zirconia;  but  when  these  were  finally  proved  and  acknowledged, 
through  some  legal  difficulties  General  Clingman  had  forfeited  his  leases, 
and  hence  failed  to  reap  his  reward.  The  zircon  industry  has  been  quite 
important  in  North  Carolina;  and  as  far  back  as  1883  Mr.  W.  E.  Hidden 
mined  26  tons  in  that  single  year.  The  chemical  composition  of  zircon 
is  shown  below  in  the  analysis  of  a  sample  of  this  mineral  from  Buncombe 
County. 

Analysis  6  of  Zircon  from  Buncombe  County,  N.  C. 
Specific   Gravity,   4.607. 

Constituent.  Per  cent.  T^° ^al 

Silica    -33.70  32.80 

Zirconia    65.30  67.20 

Ferric   Oxide    0.67  

Water    0.41  

RUTILE. 

This  is  one  of  the  most  interesting  minerals  found  in  North  Carolina, 
although  not  one  that  is  very  conspicuous.  In  composition,  it  is  pure 
oxide  of  the  metal  titanium,  and  varies  in  color  from  deep  red  or  reddish- 
brown  to  black,  the  crystals  being  modified  square  prisms.  Specimens 
from  Alexander  County  rival  any  that  have  ever  been  found  for  their 
perfection  of  form,  wonderful  polish,  and  fine  color  (PL  XIV,  A  and  B, 
and  PI.  XV).  At  Graves  Mountain,  Georgia,  elegant  rutile  occurs  with 
lazulite  usually  imbedded  in  a  compact  red  oxide  of  iron  that  can  be 
readily  removed  by  hydrochloric  acid,  or  with  a  sharp  instrument,  leaving 
on  the  surfaces  a  mirror-like  polish.  The  crystals  vary  in  length  from  -J 
an  inch  up  to  5  inches,  and  are  either  single,  twins,  or  vieriings,  often 
in  fine  groups.  The  rutile  from  this  locality  has  realized  at  least  $20,000 
for  cabinet  specimens,  and  has  supplied  the  collections  of  the  world 
through  the  perseverance  of  Prof.  Charles  IT.  Shepard.  It  occurs  in  a 
similar  association  with  lazulite  in  North  Carolina,  at  Crowders  Mountain, 
in  Gaston  County. 

The  finest  small  brilliant  geniculated  crystals  are  found  at  Millholland's 
Mills,  White  Plains,  near  Liberty  Church,  and  near  Poplar  Springs,  in 

r;C.  F.  Chandler,  analyst,  Am.  Jour.  Sci.,  II,  24,  131. 


N.    C.    GEOLOGICAL    AND    ECONOMIC    SURVEY 


BULLETIN    NO.    12.       PLATE    XIV 


1 
1 

> 

o 

r 

*-* 

Z 
> 


A.    RUTILE    CRYSTALS,    NATURAL    SIZE,    STONY    POINT,    N.    C. 


B.     RUTILE,     RETICULATED,     NATURAL     SIZE,     NEAR     HIDDEN1TE     P.     0.,     ALEXANDER     COUNTY.     N.     C. 


GARNET,    ZIRCON,    RUTILE    AND    OCTAIIEDRITE.  53 

Alexander  County,  see  Plate  XIV.  These  have  furnished  some  of  the 
finest  cut  black  rutile,  which  more  closely  approaches  the  black  diamond 
in  appearance  than  any  other  gem.  Some  of  the  lighter  colored  ones 
furnish  gems  strongly  resembling  common  garnet.  Beautiful  long  crys- 
tals at  times  transparent  red,  ranging  from  the  thickness  of  a  hair  to  J 
and  in  some  instances  §  inch  across,  and  from  1  inch  to  6  inches  in  length, 
often  doubly  terminated  and  very  brilliant,  have  been  found  at  Taylors- 
ville,  Stony  Point,  and  elsewhere  in  that  vicinity.  A  very  marked  form 
of  rutile  is  that  in  which  these  slender  red  crystals  penetrate  transparent 
quartz,  both  colorless  and  smoky,  forming  the  beautiful  combination 
called  sagenite,  or  by  the  French,  "  fleches  d'amour"  (love's  arrows) 
(PL  V).  This  material  is  found  of  remarkably  fine  quality  at  several 
points  in  North  Carolina,  and  is  described  in  this  report  under  Quartz 
Inclusions. 

Dr.  Joseph  Hyde  Pratt  has  recently  reported  the  occurrence  of  beau- 
tifully terminated  rutile  crystals  from  near  Mebane,  Orange  County.  The 
crystals  are  up  to  1J  inches  long  and  J  broad  and  are  imbedded  in 
pyrophyllite. 

OCTAHEDRITE. 

Octdhedrite  is  a  rare  mineral,  identical  with  rutile  in  composition,  but 
entirely  different  in  the  form  of  its  crystals.  It  is  described  by  W.  E. 
Hidden  7  as  occurring  in  thin  tabular,  glassy  crystals  of  a  pale-green  color 
and  very  brilliant  up  to  J  of  an  inch  in  diameter,  in  the  gold  sands  of 
Brindletown  Creek  and  elsewhere  in  Burke  and  the  adjoining  counties, 
especially  on  the  northern  slope  of  Pilot  Mountain.  These  might  afford 
small  gems  that  would  compare  favorably  with  the  beautiful  blue  crystals 
from  Brazil,  which  are  so  brilliant  as  to  have  been  mistaken  for  diamonds. 
Cassiterite,  the  oxide  of  tin,  has  been  found  in  considerable  quantities  at 
King's  Mountain.  Fine  specimens  may  be  cut  like  rutile,  but  this 
place  has  not  yielded  a  single  gem,  or  been  worked  as  yet  with  commercial 
success  for  tin. 

7  Am.  Jour.   Sci.,  Ill,  Vol.  XXII,  July,  1881,  p.   26. 


CHAPTER  VIII. 

CYANITE,    EPIDOTE,    TOURMALINE,    CHRYSOLITE     (PERI- 
DOT), SERPENTINE,  SMARAGDITE,  LAZUL1TE, 
MALACHITE,  AND  PEARLS. 

CYANITE. 

This  mineral  (also  spelled  kyanite)  is  a  subsilicate  of  alumina  almost 
identical  in  composition  with  andalusite,  and  very  closely  related  also  to 
topaz.  It  is  named  from  the  Creek  huanos,  blue,  in  allusion  to  its  pre- 
vailing color,  and  was  also  called  by  old  writers  sappar,  from  a  corruption 
of  sapphire,  which  the  fine  clear  cyanites  of  deep  tint  sometimes  resemble. 
It  occurs  generally  in  long  prismatic  or  blade-like  crystals,  and  is  not 
uncommon  in  the  gneissic  rocks  of  New  England  and  Southeastern 
Pennsylvania  to  North  Carolina  (Pis.  XIII  and  XII,  B).  It  presents 
various  shades  of  blue  and  blue-green,  occasionally  varying  to  pure  white, 
— the  variety  from  the  Tyrol  called  rhcetizite.  Fine  crystals  occur  with 
lazuli te  at  Chibb's  and  Crowder's  mountains,  on  the  road  to  Coopers 
Gap,  in  Gaston  County,  and  also  in  Rutherford  County.  Cyanite  is  some- 
what frequently  associated  with  corundum,  from  which  Dr.  Genth  believed 
it  to  be  derived  by  alteration.  Another  locality  is  at  Swannanoa  Gap, 
in  Buncombe  County;  but  the  finest  specimens  are  found  in  Mitchell 
County,1  where  it  occurs  in  distinct  isolated  crystals  that,  for  perfection. 
depth  of  color,  and  transparency,  rival  those  from  St.  Gothard, 
Switzerland.  The  locality  is  at  an  altitude  of  5500  feet,  near  the  summit 
of  Yellow  Mountain  on  the  road  to  Marion,  4  miles  southeast  of  Bakers- 
ville,  in  a  vein  of  white  massive  quartz  in  a  granitic  bluff,  associated  with 
almandite  garnet  of  a  very  light  transparent  pinkish-purple  color.  The 
vein  has  a  dip  of  60  degrees,  bearing  northeast  and  southwest.  The  color 
varies  from  almost  colorless  to  deep  azure-blue,  as  dark  as  the  Ce}Tlonese 
sapphire,  also  occasionally  green.  Some  of  the  crystals  are  2  inches  long, 
while  a  few  were  observed  f  inch  (15  millimeters)  in  width  and  f  inch 
(10  millimeters)  in  thickness.  Occurring  in  white  quartz,  they  form 
beautiful  specimens,  and  the  loose  crystals  were  extensively  sold  for 
sapphire  some  years  ago,  at  Roan  Mountain,  the  summer  resort.     A  few 

'Am.  Jour.  Sci..  III.  Vol.  XXXVI.  p.  224.  Sept.,  1888. 


CYANITE,    EPIDOTE,    TOURMALINE,    SMARAGDITE,    ETC.  55 

gems  have  been  cut,  and  a  fine  example  is  in  the  United  States  National 
Museum.    It  is,  however,  too  soft  to  admit  of  much  wear. 

Another  locality  of  fine  cyanite  in  the  same  vicinity,  was  described  in 
1898  by  Dr.  J.  H.  Pratt.2  This  was  on  the  farm  of  Mr.  T.  Young,  in 
Yancey  County,  on  North  Toe  Eiver,  a  few  miles  from  Spruce  Pine, 
Mitchell  County.  Here  the  cyanite  is  frequently  of  a  rich  mossy  green 
color,  sometimes  perfectly  transparent;  and  some  of  the  crystals  are  blue 
along  the  center  with  grass-green  margins.  Many  of  them  are  terminated, 
which  is  not  common  in  cyanite;  and  the  locality  seems  a  very  promising 
one. 

EPIDOTE. 

Prof.  Frederick  A.  Genth  mentions  3  a  crystal  of  epidote  in  the  cabinet 
of  the  University  of  Pennsylvania,  from  the  gold-washings  of  Eutherford 
County,  N.  C.  This  crystal  is  strongly  pleochroic,  like  the  so-called  pusch- 
kinite  from  the  auriferous  sands  of  Ekaterinburg,  in  the  Ural  Mountains, 
and  would  cut  into  a  small  gem.  Some  fine  highly  complex  forms  have 
been  observed  at  Hampton's,  Yancey  County,  by  William  E.  Hidden. 
These  crystals  might  possibly  afford  cabinet  gems,  not  equal,  however, 
to  the  Tyrolese  epidote.  Handsome  prismatic  crystals,  1-J  inches  in  length 
and  i  in  diameter,  have  been  reported  by  Mr.  0.  H.  Blocher,  of  Old  Fort, 
McDowell  County,  as  found  some  40  miles  from  that  place,  but  with  no 
more  specific  location.  They  are  brilliant,  but  of  too  dark  a  green  to 
have  much  promise  as  gems. 

Crocidolite  was  observed  by  Joseph  Wilcox  in  long,  delicate  fibers  of  a 
blue  color,  in  one  of  the  western  counties  of  North  Carolina. 

TOURMALINE. 

This  is  a  complex  boro-silicate  of  alumina  and  several  oxides,  which  is 
frequent  in  various  crystalline  rocks,  and  in  its  common  black  form  is 
found  at  numerous  North  Carolina  localities.  But  the  richly  colored 
varieties  which  are  valued  as  gem  stones,  and  are  found  in  Maine,  Con- 
necticut, and  Southern  California,  do  not  appear  in  North  Carolina. 
The  only  announcement  of  the  presence  of  any  of  them,  thus  far,  was 
made  several  years  ago  by  Messrs.  D.  C.  Morgan  and  Company,  of  Waynes- 
ville,  Haywood  County,  who  reported  crystals  of  transparent  green 
tourmaline  as  found  near  that  place.  The  colored  tourmalines  usually 
contain  some  lithia,  and  are  nearly  always  found,  when  they  do  occur,  in 
pegmatite  dikes.     As  these  latter  are  frequent  in  the  western  counties, 

.     2Am.  Jour.  Sci.,  IV,  Feb.,  1898,  pp.  126,  127. 

3  Minerals  and  Mineral  Localities  of  North  Carolina,  Raleigh,  p.  44,  1881. 


56  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

it  seems  remarkable  that  almost  no  tourmalines  of  this  kind  have  been 
found  in  all  the  mining  and  prospecting  work. 

CHRYSOLITE    (OLIVINE,  PERIDOT ). 

This  mineral  is  a  silicate  of  magnesia  and  iron.  It  occurs  largely  in 
an  altered  form  in  North  Carolina,  as  the  leading  constituent  of  the 
decomposed  peridotites  called  dunites,  but  very  rarely  in  its  unchanged 
condition.  It  is  a  green  to  yellow  mineral,  nearly  as  hard  as  quartz 
(6.5-7),  and  when  transparent  and  in  pieces  of  any  size,  it  is  valued 
as  a  brilliant  gem-stone, — the  chrysolite  or  peridot  of  jewelers.  Xear 
Webster,  in  Jackson  County,  it  is  found  in  granular  masses,  of  a  bright 
yellow-green  color,  and  susceptible  of  a  fine  high  polish.  This  material. 
if  present  in  any  quantity,  might  be  utilized  as  a  pleasing  ornamental 
stone;  but  not  as  a  gem,  unless  more  transparent  and  in  larger  pieces. 

Analyses  of  Chrysolite  from  Wedster,  Jackson  County    N.  C. 

Constituent.  Percent.4     Percent.5      Percent.0 

Silica    41.89  40.74  41.17 

Ferric  Oxide       )  n  co  1  00 

- U.Oo  l.oo  

Chromic  Oxide  ) 

Ferrous  Oxide 7.39  7.26  7.35 

Nickel  Oxide   0.35  0.39  0.41 

Lime    0.06  0.02  0.04 

Magnesia 49.13  49.18  49.16 

4  F.  A.  Genth,  analyst,  Am.  Jour.  Sci.,  Ill,  33,  200. 

51.  c. 

eF.  A.  Genth,  analyst,  Am.   Jour.   Sci.,  II,  33,   199. 

4  Color,  pale  grayish  green. 

5  and  6  Color,  yellowish  olive  green. 

SERPENTINE. 

This  mineral,  a  hydrous  silicate  of  magnesia,  occurs  widely  distributed 
throughout  some  portions  of  the  State,  and  is  often  a  result  of  the  alter- 
ation of  the  olivine-bearing  rocks  (peridotite,  dunite)  already  repeatedly 
mentioned.  At  some  points  it  is  massive  and  of  good  color  and  quality, 
such  as  might  be  used  for  building-stone,  as  it  is  frequently  near  Phila- 
delphia. But  the  translucent  and  rich  green  variety  known  as  precious 
serpentine,  which  is  used  as  an  ornamental  stone  like  that  of  Maryland, 
has  been  recognized  only  at  a  few  points  and  does  not  appear  as  yet  to 
have  been  utilized  at  all.  Dr.  Pratt  mentions  several  promising  outcrops 
in  Buncombe  County,  between  Leicester  and  Weaversville.  and  others  in 
Madison  and  Yancey  counties.  Still  another,  where  the  serpentine  is  of 
fine  quality,  is  in  Wilkes  County,  where  it  forms  the  rock  of  the  asbestos 


N.    C.   GEOLOGICAL   AND   ECONOMIC   SURVEY 


BULLETIN    NO.    12.       PLATE    XV 


CYANTTE,    EPIDOTE,    TOUKMALINE,    SMARAGDITE,    ETC.  57 

mine  near  North  Wilkesboro.  It  is  hard  and  compact  and  polishes  hand- 
somely, and  might  prove  as  beautiful  as  that  of  Harford  County,  Mary- 
land. Dr.  Genth,  also,  years  ago,  stated  that  a  serpentine  from  the 
neighborhood  of  Patterson,  Caldwell  County,  of  a  dark  greenish-black 
color,  admits  of  a  fine  polish.7 

Analysis 8  of  Serpentine,  Webster,  N.  G. 

Constituent.  Per  cent. 

Silica    43.87 

Alumina    0.31 

Ferrous  Oxide  7.17 

Nickel  Oxide  0.27 

Magnesia    38.62 

Water    9.55 

EDENITE    (  SMARAGDITE. ) 

Smaragdite  is  a  variety  of  hornblende  (amphibole),  which  occurs 
plentifully  at  the  Cullakenee  Corundum  Mine,  Clay  County,  N.  C.  In 
color  it  is  bright  emerald  to  grass-green,  also  grayish  and  greenish-gray. 
Masses  through  which  the  pink  and  ruby  corundum  occur  disseminated, 
are  exceedingly  beautiful.  The  mineral  is  hard  enough  to  admit  of  a  fine 
polish  and  is  worthy  of  attention  as  an  ornamental  or  decorative  stone. 
It  has  recently  been  utilized  for  such  purposes,  under  the  name  of  "  ruby 
matrix."  Pieces  are  selected  in  which  bright  portions  of  red  or  pink 
corundum  are  enclosed  in  the  rich  green  smaragdite,  and  the  contrast 
makes  a  very  attractive  material.  Smaragdite  occurs  also  near  Elf,  on 
Shooting  Creek,  in  the  same  county,  similarly  associated  with  corundum, 
pink  and  dark  blue. 

LAZULITE. 

Lazulite  is  a  somewhat  rare  mineral,  a  phosphate  of  alumina  containing 
some  magnesia  and  protoxide  of  iron.  It  occurs  in  pale  and  dark  blue 
crystals  and  crystalline  masses  at  Clubb  Mountain  and  Crowder's  Moun- 
tain, in  Gaston  County,  and  at  Sauratown,  in  Stokes  County.  The  finest 
crystals,  however,  come  from  Graves'  Mountain,  Georgia,  some  of  the m 
being  as  much  as  two  inches  in  length.  Its  hardness  is  6,  and  its  specific 
gravity  is  3.122.  This  mineral  would  make  an  opaque  gem  or  an  orna- 
mental stone,  as  the  color,  though  lighter,  is  often  as  rich  as  that  of  lapis 
lazuli,  for  which  it  was  mistaken  when  first  found. 

7  Mineral  of  N.  C,  p.  57. 

8F.  A.  Genth,  analyst,  Am.  Jour.  Sci.,  II.  33.  201. 


58  HISTORY  OF  THE  GEMS  FOUND  IN  NORTH  CAROLINA. 

Analysis  9  of  Blue  Lazulite  from  Gaston  County,  N.  C. 

Constituent.                                     Per  cent.  Per  cent. 

Phosphoric  Acid   43.38  44.15 

Alumina    31.22  32.17 

Ferrous  Oxide   8.29  8.05 

Magnesia    10.06  10.02 

Silica    1.07  1.07 

Water    5.68  5.50 

Hardness    5.0-6.0  5.0-6.0 

MALACHITE. 

This  beautiful  green  carbonate  of  copper,  often  used  as  an  ornamental 
stone  as  well  as  mined  for  an  ore  of  the  metal,  is  found  somewhat  in 
Guilford,  Cabarrus,  and  Mecklenburg  counties.  The  fibrous  variety  has 
been  observed  at  Silver  Hill  and  at  Conrad  Hill,  in  Davidson  Count}7,  and 
in  a  number  of  other  localities  in  North  Carolina,  but  is  rarely  of  any  gem 
value.  In  the  Torrey  Collection  at  the  United  States  Assay  Office,  in 
New  York  City,  are  a  few  fine  gem  pieces  of  malachite  from  the  Copper 
Knob  mine  in  Ashe  County. 

PEARLS. 

The  Indians  of  Carolina,  Georgia,  Florida  and  Alabama,  gathered 
mussels  and  conchs,  as  shown  by  the  numerous  refuse  piles  and  shell 
heaps  that  abound  upon  the  salt-water  creeks.  It  is  not  a  matter  of 
surprise  that  the  Indians,  as  they  opened  these  shells,  should  have  care- 
fully watched  for  pearls,  and  from  the  vast  numbers  examined,  should 
have  accumulated  a  store.  If  the  shores  of  Carolina,  Georgia,  and 
Florida  did  not  afford  the  larger  and  more  highly  prized  pearls,  it  is 
not  impossible  that  pearls  from  the  islands  and  lower  portions  of  the 
Gulf  of  Mexico,  and  even  from  the  Pacific  coast,  may  have  found  their 
way  into  the  heart  of  Georgia  and  Florida  and  into  more  northern 
localities,  to  be  there  bartered  away  for  skins  and  other  articles.  The 
replies  of  Indians  to  Father  Hennepin  and  others  and  the  presence  in 
remote  localities  of  beads,  ornaments,  and  drinking-cups  made  of  marine 
shells  and  conchs,  still  peculiar  to  the  Gulf  of  Mexico,  confirm  the 
truthfulness  of  this  suggestion.10 

9  Analysts,  Smith  &  Brush.     Dana,  Mineralogy,  5th  ed.,  p.  572. 

10  Ancient  Aboriginal  Trade  in  North  America,  by  Charles  Rau.  Report  of  the 
Smithsonian  Institution  for  1872,  Washington,  1873 ;  Gems  and  Precious  Stones  of 
North  America,  New  York,  1890-92 ;  TJ.  S.  Commission  Fish  and  Fisheries,  1S93-9S ; 
Pearls,  by  Geo.  F.  Kunz,  Charles  H.  Stevenson,  Century  Co.,  New  York,  1907. 


I 


PUBLICATIONS 

OF    THE 

NORTH  CAROLINA  GEOLOGICAL  AND  ECONOMIC  SURVEY. 


BULLETINS. 

1.  Iron  Ores  of  North  Carolina,  by  Henry  B.  C.  Nitze,  1893.  8°,  239  pp.,  20 
pi.,  and  map.     Postage  10  cents. 

2.  Building  and  Ornamental  Stones  in  North  Carolina,  by  T.  L.  Watson  and 
F.  B.  Laney  in  collaboration  with  George  P.  Merrill,  1906.  8°,  283  pp.,  32  pi., 
2  figs.     Postage  25  cents.     Cloth-bound  copy  50  cents  extra. 

3.  Gold  Deposits  in  North  Carolina,  by  Henry  B.  C.  Nitze  and  George  B. 
Hanna,  1896.     8°,  196  pp.,  14  pi.,  and  map.     Out  of  print. 

4.  Road  Material  and  Road  Construction  in  North  Carolina,  by  J.  A.  Holmes 
and  William  Cain,  1893.     8°,  88  pp.     Out  of  print. 

5.  The  Forests,  Forest  Lands  and  Forest  Products  of  Eastern  North  Caro- 
lina, by  W.  W.  Ashe,  1894.     8°,  128  pp.,  5  pi.     Postage  5  cents. 

6.  The  Timber  Trees  of  North  Carolina,  by  Gifford  Pinchot  and  W.  W.  Ashe, 
1897.     8°,  227  pp.,  22  pi.     Postage  10  cents. 

7.  Forest  Fires:  Their  Destructive  Work,  Causes  and  Prevention,  by  W.  W. 
Ashe,  1895.     8°,  66  pp.,  1  pi.     Postage  5  cents. 

8.  Water-powers  in  North  Carolina,  by  George  F.  Swain,  Joseph  A.  Holmes 
and  E.  W.  Myers,  1899.     8°,  362  pp.,  16  pi.     Postage  16  cents. 

9.  Monazite  and  Monazite  Deposits  in  North  Carolina,  by  Henry  B.  C.  Nitze, 
1895.     8°,  47  pp.,  5  pi.     Postage  h  cents. 

10.  Gold  Mining  in  North  Carolina  and  other  Appalachian  States,  by  Henry 
B.  C.  Nitze  and  A.  J.  Wilkins,  1897.     8°,  164  pp.,  10  pi.     Postage  10  cents. 

11.  Corundum  and  the  Basic  Magnesian  Rocks  of  Western  North  Carolina, 
by  J.  Volney  Lewis,  1895.     8°,  107  pp.,  6  pi.     Postage  4  cents. 

12.  History  of  the  Gems  found  in  North  Carolina,  by  George  Frederick 
Kunz,  1907.     8°,  60  pp.,  15  pi.     Postage  6  cents. 

13.  Clay  Deposits  and  Clay  Industries  in  North  Carolina,  by  Heinrich  Reis, 
1897.     8°,  157  pp.,  12  pi.     Postage  10  cents. 

14.  The  Cultivation  of  the  Diamond-back  Terrapin,  by  R.  E.  Coker,  1906. 
8°,  67  pp.,  23  pi.,  2  figs.     Postage  6  cents. 

15.  Experiments  in  Oyster  Cultutre  in  Pamlico  Sound,  by  Robert  E.  Coker. 
In  press. 

16.  A  List  of  Elevations  in  North  Carolina,  by  Joseph  Hyde  Pratt  and 
E.  W.  Myers.    In  preparation. 

17.  The  Loblolly  Pine  in  Eastern  North  Carolina,  by  W.  W.  Ashe.  In  prepa- 
ration. 

18.  Shade  Trees  in  North  Carolina,  by  W.  W.  Ashe.    In  preparation. 

19.  The  Tin  Deposits  of  the  Carolinas,  by  Joseph  Hyde  Pratt  and  Douglass 
B.  Sterrett,  1905.     8°,  64  pp.,  8  figs.     Postage  J,  cents. 

ECONOMIC    PAPERS. 

1.  The  Maple-Sugar  Industry  in  Western  North  Carolina,  by  W.  W.  Ashe, 
1897.     8°,  34  pp.     Postage  2  cents. 


60  LIST   OF  PUBLICATION'S. 

2.  Recent  Road  Legislation  in  North  Carolina,  by  J.  A.  Holmes.     Out  of 
print. 

3.  Talc  and  Pyrophyllite  Deposits  in  North  Carolina,  by  Joseph  Hyde  Pratt, 
1900.     8°,  29  pp.,  2  maps.     Postage  2  cents. 

4.  The  Mining  Industry  in  North  Carolina  During  1900,  by  Joseph  Hyde 
Pratt,  1901.     8°,  36  pp.,  and  map.     Postage  2  cents. 

5.  Road  Laws  of  North  Carolina,  by  J.  A.  Holmes.     Out  of  print. 

6.  The  Mining  Industry  in  North  Carolina  During  1901,  by  Joseph  Hyde 
Pratt,  1902.     8°,  102  pp.     Postage  4  cents. 

7.  Mining  Industry  in  North  Carolina  During  1902,  by  Joseph  Hyde  Pratt, 
1903.     8°,  27  pp.     Postage  2  cents. 

8.  The  Mining  Industry  in  North  Carolina  During  1903,  by  Joseph  Hyde 
Pratt,  1904.     8°,  74  pp.     Postage  4  cents. 

9.  The  Mining  Industry  in  North  Carolina  During  1904,  by  Joseph  Hyde 
Pratt,  1905.     8°,  95  pp.     Postage  J,  cents. 

10.  Oyster  Culture  in  North  Carolina,  by  Robert  E.  Coker,  1905.     8°,  39  pp. 
Postage  2  cents. 

11.  The  Mining  Industry  in  North  Carolina  During  1905,  by  Joseph  Hyde 
Pratt,  1906.     8°,  95  pp.     Postage  4  cents. 

12.  Investigations  Relative  to  the  Shad  Fisheries  of  North  Carolina,  by  John 
N.  Cobb,  1906.     8°,  74  pp.,  8  maps.     Postage  6  cents. 

13.  Report   of   Committee   on    Fisheries    in   North    Carolina.     Compiled   by 
Joseph  Hyde  Pratt,  1906.     8°,  78  pp.     Postage  4  cents. 

14.  Mining  Industry  of  North  Carolina  during  1906,  by  Joseph  Hyde  Pratt, 
A.  A.  Steel,  and  Douglas  B.  Sterrett.    In  press. 


VOLUMES. 

Vol.  I.  Corundum  and  the  Basic  Magnesian  Rocks  in  Western  North  Caro- 
lina, by  Joseph  Hyde  Pratt  and  J.  Volney  Lewis,  1905.  8°,  464  pp.,  44  pi., 
35  figs.     Postage  32  cents.     Cloth-bound  copy  50  cents  extra. 

Vol.  II.     The  Fish  of  North  Carolina,  by  H.  M.  Smith.     In  press. 

Vol.  III.  Miscellaneous  Mineral  Resources  in  North  Carolina,  by  Joseph 
Hyde  Pratt.     In  preparation. 

y  Vol.  IV.     Mica  Deposits  of  Western  North  Carolina,  by  Joseph  Hyde  Pratt 
and  Douglas  B.  Sterrett.     In  preparation. 


Samples  of  any  mineral  found  in  the  State  may  be  sent  to  the  office  of  the 
Geological  and  Economic  Survey  for  identification,  and  the  same  will  be 
classified  free  of  charge.  It  must  be  understood,  however,  that  xo  assays,  or 
quantitative  detekminations,  will  be  made.  Samples  should  be  in  a  lump 
form  if  possible,  and  marked  plainly  with  name  of  sender  outside  of  package, 
post-office  address,  etc.;  a  letter  should  accompany  sample  and  stamp  should 
be  enclosed  for  reply. 


These  publications  are  mailed  to  libraries  and  to  individuals  who  may  de- 
sire information  on  any  of  the  special  subjects  named,  free  of  charge,  except 
that  in  each  case  applicants  for  the  reports  should  forward  the  amount  of 
postage  needed,  as  indicated  above,  for  mailing  the  bulletins  desired,  to  the 
tttate  Geologist,  Chapel  Hill,  N.  C. 


\ 


k 


O 

O  "S 

Q-  X 

oo 

S  I 

CC  TO 

O  co 

£  =0 


NORTH  CAROLINA  GEOLOGICAL  SURVEY 


J.   A.   HOLMES,   STATE  GEOLOGIST 


BULLETIN  No.  13 


CLAY  DEPOSITS  AND  CLAY  INDUSTRY 
IN  NORTH  CAROLINA 


A  PRELIMINARY  REPORT 


HEINRICH  RIES 


RALEIGH 

Guy  V.  Barnes,  Public  Printer 
1897 


Hf'lJL- 


i 


CONTENTS 


PAGE 

Illustrations 6 

Letter  of  Transmittal 8 

Preface 9 

Chapter  I. — The  Origin  of  Clay    11 

Chapter  II. — Chemical  properties  of  clay 15 

Impurities  in  clay 15 

Fluxing  impurities  .  . 16 

Alkalies  in  clay 1G 

Soluble  alkaline  compounds 17 

Insoluble  alkaline  compounds 17 

Compounds  of  iron  in  clay 18 

Lime  in  clay ;  .  .  20 

Effect  on  the  brick  of  calcium  carbonate  in  clay 21 

Magnesia  in  clays 23 

Non-fluxing  impurities  , 23 

Silica 24 

Titanium 24 

Organic  matter 25 

Water 26 

Methods  employed  in  making  clay  analyses    2T 

The  rational  analysis  of  clay 30 

Chapter  III. — Physical  properties  of  clay 33 

Plasticity 33 

Tensile  strength 34 

Shrinkage 35 

Fusibility 36 

Temperature  at  which  clay  fuses 37 

Measurement  of  temperatures 3S 

The  thermo-electric  pyrometer 38 

Seger's  pyramids :'»s 

Slaking  of  clays 42 

Minor  physical  properties  of  clays 42 

Absorption  of  water 42 

Texture 42 

Taste 4:; 

Color 4:; 

Density 43 


4  CONTENTS. 

PAGE 

Chapter  IV. — Geology  and  geography  of  North  Carolina  clay  deposits 44 

Residual  clays , 44 

Sedimentary  clays 46 

The  North  Carolina  clay  working  industry 48 

Chapter  V. — Kaolins  or  china  clays 50 

Character,  Mining,  Preparation  for  market 50 

Distribution  of  the  kaolins 50 

Mineralogical  character  of  kaolin 50 

Properties  of  kaolin 51 

Mining  of  kaolin 53 

Preparation  of  kaolin  for  market 54 

Deposits  of  kaolin  in  North  Carolina 58 

Kaolin  in  Jackson  county 58 

Macon  county 62 

Montgomery  county 64 

Richmond  county 65 

Uses  of  the  North  Carolina  kaolins 68 

Chapter  VI. — Pottery  Clays  in  North  Carolina 71 

The  pottery  industry 71 

Requisites  of  a  pottery  clay 72 

Stoneware  manufacture 73 

Pottery  industry  in  Burke  county 75 

Catawba  county 76 

Lincoln  county 77 

Wilkes  county 78 

Chapter  VII. — Fire-clays  and  pipe-cla}rs  in  North  Carolina 80 

Fire-clays SO 

Fire-clays  in  Cleveland  county 81 

Guilford  county S3 

Pipe-clays  in  North  Carolina S6 

Manufacture  of  sewer  pipes  and  tiles S6 

Guilford  county SS 

Chapter  VIII. — Brick-clays  and  brick  manufacturing 92 

General  character  of  brick-clays 92 

Requisites  of  brick-clays 93 

Methods  of  brick  manufacture 94 

Soft-mud  process 94 

Stiff-mud  process 96 

Dry-press  process 99 

Chapter  TX. — Brick-clay  deposits  in  North  Carolina 102 

Brick-clays  in  Bladen  county 102 

Buncombe  county 104 

Burke  county 107 

Cleveland  county 108 

Cumberland  county 110 

Forsyth  county Ill 

Gaston  county 113 


CONTENTS.  5 

PAGE 
Chapter  IX. — Continued. 

Brick-clays  in  Guilford  county 114 

Halifax  county , 116 

Harnett  county 119 

Jackson  county 121 

Martin  county 122 

Mecklenburg  county 122 

Richmond  county 125 

Robeson  county 126 

Rowan  county , 127 

Surry  county 128 

Union  county 129 

Wake  county 130 

Wayne  county 131 

Wilkes  county 134 

Wilson  county 136 

Comparison  of  Wilson  and  Wayne  county  clays 138 

Chapter  X. — Manufacture  of  paving-brick 139 

Requisite  character  of  clay 139 

Manufacture  of  paving-brick 140 

Table  of  Chemical  Analysis  of  Clays „ 142 

Table  of  Physical  Properties  of  Clays 146 

Bibliography 150 

Index 153 


ILLUSTRATIONS. 


PAGE 

Plate  I.     Pomona  Terra  Cotta  Works,  Pomona,  N.  C Frontispiece. 

II.     Map  showing  distribution  of  geological  formations  in  Xorth  Carolina  .  .  44 

III.  Fig.  1,  Kaolin  washing  and  drying  plant,  Harris  Clay  Co 56 

2,  Harris  Clay  Co.'s  mine,  showing  method  of  sinking  pits  in  soft 

kaolin 56 

IV.  Fig.  1,  Wooden  frame  kaolin  filter-press -. 58 

2,  Iron  frame  kaolin  filter-press 58 

V.     Fig.  1,  Residual  kaolin  deposit,  Harris  Clay  Co.'s  mine,  near  Webster..  .  59 

2,  Residual  clay  deposit,  Powhatan  Clay  Mfg.  Co.,  near  Grover 59 

VI.     Fig.  1,  Press  for  sewer-pipe,  tile,  and  hollow  brick 86 

2,  Chaser  mill  for  tempering  clay  for  sewer-pipe 86 

VII.     Fig.  1,  Circular  down-draft  kiln  for  tile,  etc 88 

2,  Tunnel  dryers,  used  in  brick  making 88 

VIII.     Fig.  1,  Stiff-mud  auger  end-cut  brick  machine ." .  98 

2,  Re-pressing  brick  machine 98 

IX.     Fig.  1,  Interior  view  of  a  continuous  brick-kiln 99 

2,  Exterior  view  of  a  continuous  brick-kiln 99 

X.     Fig.  1,  Up-draft  brick-kilns,  for  burning  common    brick,    at  the   State 

Penitentiary,  Raleigh,  N.  C 101 

2,  Down-draft  brick-kiln.     Eudaly  type 101 

XL     Fig.  1,  Black  clay  along  Cape  Fear  river,  at  Prospect  Hall 110 

2,  Poe  Bros',  clay  bank,  Fayetteville,  N.  C 110 

XII.     Fig.  1,  Brick  works  of  Carter  and  Shepard,  Bethania 120 

2,  Clay  deposit  in  railway  cut,  Spout  Springs,  C.  F.  &  Y.  V.  railroad.  120 

Fig.    1.      Pump  for  removing  kaolin  from  settling  vats  and  forcing  it  into  the  presses.  57 

2.  Potter's  jolly,  No.  3 74 

3.  Vaughan  sewer-pipe  press S7 

4.  Dry-pan  crusher 97 

5.  Dry-press  brick  machine 100 


■ 


BOARD  OF  MANAGERS. 

Govern ob.  D.  L.  Russell,  ex-officio  Chairman,         .         .  Raleigh. 

Charles  MoNamee,       .......  Biltmore. 

J.  Turner  Morehead,  ......  Leaksville. 


STATE  GEOLOGIST. 
J.  A.  Holmes, Chapel  Hill. 


LETTER  OF  TRANSMITTAL. 


To  His  Excellency,  Hon.  D.  L.  Russell, 

Governor  of  North  Carolina 

and  Chairman  of  the  Geological  Board. 

Sir: — I  have  the  honor  to  transmit  as  bulletin  13  of  the  Survey  series, 
a  preliminary  report  on  some  of  the  clay  deposits  and  the  clay  industry 
in  North  Carolina,  by  Dr.  Heinrich  Hies.  This  report  is  not  intended 
as  a  complete  or  final  discussion  of  the  clay  deposits  of  this  State.  Their 
examination  has  thus  far  been  limited  mainly  to  the  regions  about  towns 
and  railway  stations,  where  the  need  for  information  is  greatest:  but 
during  the  next  few  years  it  is  expected  that  this  work  will  be  ex- 
tended to  all  portions  of  the  State  where  there  is  a  probability  of  dis- 
covering workable  deposits  of  clay  or  kaolin. 

Meanwhile  it  is  thought  best  to  publish,  in  response  to  the  calls  for 
immediate  information,  this  preliminary  report,  which  I  regard  as  an 
important  contribution  to  our  series  of  reports  on  North  Carolina 
resources.  I  believe  it  will  be  well  received  by  the  clay  workers  of  the 
State,  and  hope  that  it  will  prove  useful  to  them. 

Yours  obediently, 

J.  A.  Holmes, 

State  Geologist. 

Raleigh,  N.  C, 

July  15,  1897. 


PREFACE 


The  following  investigation  of  the  North  Carolina  clays  was  under- 
taken for  the  purpose  of  determining  (1)  the  extent,  qualities,  appli- 
cability of  the  clays  occurring  within  the  State;  and  (2)  whether  those 
deposits  now  being  utilized  could  be  used  for  making  other  or  better 
products  than  those  that  are  now  being  manufactured  from  them, 
by  varying  the  mixtures  or  by  the  use  of  different  appliances  in  the 
manufacture.  The  field  work  was  earned  on  during  the  spring  and 
autumn  of  1896,  and  many  of  the  clay  deposits  (nearly  100)  were 
visited.  Samples  were  collected  from  about  seventy  beds  and  sub- 
mitted to  chemical  and  physical  investigation. 

The  chemical  work  was  earned  out  in  a  careful  and  detailed  manner 
by  Prof.  Chas.  Baskerville,  of  the  University  of  North  Carolina.  In 
each  case  the  constituents  determined  were  free  and  combined  silica, 
alumina,  ferric  oxide,  lime,  magnesia,  alkalies,  moisture,  and  water.  In 
certain  cases  determinations  were  also  made  of  the  ferrous  oxide,  organic 
matter,  sulphur,  and  titanic  oxide.  Of  the  high  grade  clays,  such  as  the 
kaolins,  a  rational  analysis  was  made  in  each  case.  This,  though  of 
great  importance,  has  rarely  been  done  in  this  country,  although  it  is 
often  carried  out  abroad.  From  the  rational  analysis,  as  pointed  out 
in  the  report,  it  is  possible  to  compute  the  percentage  of  clay  substance, 
quartz,  and  feldspar  in  the  clay,  a  fact  which  is  of  great  practical  value 
to  the  manufacturer,  for  it  gives  him  an  important  guide  in  making  up 
the  mixture  for  the  body. 

The  physical  investigations  consisted  in  determining  the  amount  of 
water  required  to  be  added  to  give  a  workable  mass,  the  shrinkage  in 
drying  and  burning  of  bricklets  made  from  this  mud;  the  color  to  which 
the  clay  burns;  the  temperatures  of  incipient  fusion,  vitrification,  and 
viscosity;  the  cohesion  or  tensile  strength  of  the  air-dried  clay,  deter- 
mined by  making  briquettes  and  pulling  them  apart  in  a  cement  testing 


1 0  PREFACE. 

machine;  the  texture  of  the  clay;  the  slaking  in  water;  and  other  minor 
physical  characteristics. 

The  fire  tests  were  carried  on  in  a  regenerative  gas  furnace  for  tem- 
peratures up  to  2500  degrees  F.,  but  for  temperatures  above  this  a 
Deville  furnace  was  used. 

The  results  of  the  work  show  that  North  Carolina  contains  an  abun- 
dance of  kaolin  of  superior  quality,  as  well  as  clays  for  the  manufacture 
of  stoneware,  pressed  brick,  sewer  pipe,  and  probably  paving  brick  if  a 
mixture  of  clays  is  used. 

The  presence  of  good  clays  for  the  better  grades  of  structural  mate- 
rial is  of  itself  a  matter  of  importance,  as  at  present  nearly  all  such 
wares  are  brought  from  other  States  at  considerable  cost.  While  the 
sedimentary  "  bottom "  clays  yield  smoother  and  usually  better  pro- 
ducts than  the  residual  ones,  still  experiments  and  practical  tests  show 
that  the  product  made  from  the  latter  is  materially  improved  by  the 
proper  manipulation. 

Many  of  the  products  are  easily  accessible,  being  situated  either  along 
navigable  rivers  or  near  the  intersection  of  important  lines  of  traffic. 

As  only  a  portion  of  the  clay  deposits  has  as  yet  been  examined,  this 
must  be  regarded  as  a  preliminary  report.  It  is  expected  that  these 
investigations  will  be  continued  until  the  more  promising  clay  deposits 
in  all  parts  of  the  State  shall  have  been  examined,  and  a  final  and  more 
elaborate  report  will  then  be  prepared  for  publication. 

Acknowledgments  are  due  to  the  clay  workers  of  the  State  for  the 
uniform  courtesy  with  which  they  have  aided  the  gathering  of  informa- 
tion for  this  report. 

The  American  Clay-working  Machinery  Co.,  of  Bucyrus,  O.,  The 
Turner,  Vaughn  and  Taylor  Co.,  of  Cuyahoga  Tails,  O.,  and  the 
Director  of  the  New  York  State  Museum  have  kindly  loaned  several 
of  the  illustrations  for  this  report. 

ITeixkich  TIies. 

May  9,  181)7. 


CLAY  DEPOSITS  AND  CLAY  INDUSTRY  IN  NORTH 

CAROLINA. 

By  Heinrich  Bjes,  Ph.  D. 


CHAPTER  I. 

THE  OEIGIJST  OF  CLAY. 

Forming  as  it  does  one  of  the  most  abundant  materials  of  the  sur- 
face of  the  earth's  crust,  the  enormously  extensive  application  of  clay 
is  not  to  be  wondered  at.  It  is  to  be  found  almost  everywhere,  but 
varies  greatly  in  form,  color,  and  other  chemical  and  physical  char- 
acters. There  are  two  properties,  however,  which  are  more  or  less  con- 
stant, and  by  means  of  which  clay  can  be  generally  recognized.  These 
are  plasticity  when  wet,  so  that  any  form  can  be  given  it  by  pressure; 
and  the  retention  of  this  form  when  air-dried. 

Pure  clay  is  composed  of  the  mineral  kaolinite,  which  is  a  hydrated 
silicate  of  alumina,  and  masses  of  it  are  called  kaolin.  It  rarely  hap- 
pens that  kaolin  is  found  in  a  strictly  pure  state,  for  more  or  less  foreign 
mineral  matter  is  usually  present,  and  may  form  such  a  large  percentage 
of  the  kaolin  as  to  completely  mask  the  kaolinite.  The  latter  is  known 
as  the  clay  substance,  the  foreign  minerals  being  regarded  as  impurities. 

Clay  may  therefore  be  defined  as  a  mixture  of  kaolinite  with  more  or 
less  quartz  and  other  mineral  fragments  (hydrates,  silicates,  etc.)  pos- 
sessing usually  plasticity  when  mixed  with  water,  and  when  subjected 
to  a  high  heat  becoming  converted  into  a  hard,  rock-like  mass.1 

Kaolinite,  the  base  of  all  clays,  is  not  an  original  mineral  of  the 
earth's  crust,  but  a  secondary  one,  resulting  from  the  decomposition  of 
feldspars,  and  possibly  sometimes  from  other  aluminous  mineral-.  The 
feldspars  are  a  group  of  silicate  minerals  of  rather  complex  composition, 
but  orthoclase  (the  common  feldspar),  which  serves  as  the  type  of  the 
group,  is  a  compound  of  silica,  alumina,  and  potash,  or  in  other  words, 
a  double  silicate  of  alumina  and  potash. 

The  change  to  kaolinite  is  brought  about  by  weathering  agents  oi 
the  atmosphere  which  are  continually  at  work  on  the  minerals  of  the 
earth's  crust,   disintegrating  them  or  converting  them  into   new   uiiu- 

1  The  flint  clays,  though  nearly  pure  kaolinite,  possess  little  or  no  plasticity. 


12  CLAY    DEPOSITS    IN    XORTH    CAROLINA. 

eral  compounds.  The  most  active  weathering  agents  are  oxygen  and 
carbon  dioxide,  which  by  percolating  waters  are  carried  into  the 
most  remote  cracks  and  crevices  of  the  rocks,  and  attack  the  various 
mineral  compounds,  simply  oxidizing  some,  decomposing  others  and 
carrying  part  of  their  elements  off  as  carbonates,  while  silica  may  be 
left  behind. 

Under  the  action  of  these  weathering  agencies  the  feldspar  is  decom- 
posed, the  potassium  being  removed  in  the  form  of  carbonate,  while  the 
silica  and  alumina  remain  behind,  and  with  water  form  the  hydrated 
silicate  of  alumina  or  kaolinite,  whose  composition  is  expressed  by  the 
formula  A1203,  2Si02,  2II20;  or  in  the  proportions  of  silica  (Si02) 
46.3^,  alumina  (A1203)  39. 8$,  water  (H20)  13.9^. 

It  sometimes  happens  that  the  percentage  of  alumina  in  clay  is  over 
39.8,  as  in  the  case  of  many  of  the  Missouri  flint-clays,  and  TTheeler  has 
suggested  that  they  may  be  mixtures  of  kaolinite  and  pholerite.1  The 
latter  is  an  amorphous  variety  of  the  former  and  contains  -±5^  of 
alumina. 

The  purity  of  a  clay  as  formed  will  depend  largely  on  the  nature  of 
the  parent  rock  or  the  associations  of  the  feldspar.  This  mineral  fre- 
quently occurs  in  large  vein-like  masses,  in  which  case  its  decomposition 
would  yield  a  bed  of  nearly  pure  kaolin,  but  more  frequently  it  is  asso- 
ciated with  quartz,  or  with  quartz  and  mica,  etc.  When  these  pegma- 
tite or  granite  veins  decompose,  the  result  is  a  bed  of  kaolin  with  par- 
ticles of  angular  quartz  and  flakes  of  mica,  etc.,  scattered  through  it. 
These  mineral  impurities  can  usually  be  separated  by  washing. 

Beds  of  kaolin  occurring  in  or  very  close  to  their  place  of  origin  are 
known  as  residual  clays,  and  they  may  represent  the  purest  as  well  as 
the  most  impure  forms  of  clay.  The  mineral  impurities  commonly 
found  in  residual  clays  are  feldspar,  quartz,  mica,  garnet,  hornblende, 
augite,  rutile,  etc.  Residual  clays  may  form  small  vein-like  masses, 
or  be  of  enormous  extent.  The  kaolins  near  \Vebster  and  Sylva  are 
examples  of  the  former,  the  surface  clays  around  Greensboro  of  the 
latter. 

In  the  erosion  of  the  earth's  surface  the  residual  clay  is  washed  down 
into  the  lakes  and  seas,  where  it  is  deposited  in  the  form  of  a  sediment, 
but  with  the  addition  of  many  impurities. 

Clays  thus  deposited  are  known  as  sedimentary  clays,  and  are  usually 
far  more  plastic  than  the  residual  clays  mentioned  above. 

The  clays  of  the  Cretaceous  and  Tertiary  formations  bordering  the 
Atlantic  coast  are  all  of  sedimentary  origin.  Shales  are  simply  har- 
dened clays,  their  rock-like  character  being  due  to  their  having  been 
buried  more  or  less  deeply  under  other  sediments  formed  subsequent 

iMo.  Geol.  Surv.,  XI,  1897. 


THE    ORIGIN    OF    OkAY.  13 

to  them.  On  grinding  them  to  a  powder  and  mixing  them  with  water, 
they  become  plastic  just  like  other  clays. 

By  metamorphism  a  shale  may  lose  its  chemically  combined  water, 
develop  a  cleavage,  and  become  converted  into  a  slate.  It  is  then  no 
longer  possible  to  develop  any  plasticity  by  grinding  and  mixing  with 
water. 

Sedimentary  clays  may  vary  widely  in  their  nature,  even  in  the 
same  formation  and  within  small  areas.  This  is  due  to  the  variations  in 
direction  and  velocity  of  currents  in  the  bodies  of  water  where  they 
were  deposited,  for  the  finer  clay  would  only  be  dropped  in  quiet  water, 
while  where  currents  existed  coarse  sand  only  might  be  deposited. 

Variations  in  the  current  at  the  same  point  would  produce  alter- 
nating beds  of  clay  and  sand,  while  similar  causes  might  develop  large 
lenses  of  clay,  free  from  sand  or  comparatively  so,  surrounded  by  coarse 
sand  beds.  The  kaolin  deposits  of  Aiken,.  South  Carolina,  and  the 
black  clays  exposed  in  the  bluffs  at  Prospect  Hall,  Xorth  Carolina,  are 
examples  of  this. 

Sedimentary  clays  may  be  either  soft  or  hard.  In  the  latter  case 
they  are  known  as  shales.  Shales,  on  account  of  their  rockdike  con- 
dition, are  frequently  deceptive,  yet  when  ground  and  mixed  with 
water  they  possess  the  same  plasticity  as  soft  clay.  On  account  of  the 
fusible  impurities  which  they  frequently  contain,  they  are  found  to 
be  admirably  suited  to  the  manufacture  of  vitrified  wares,  but  in  Xorth 
Carolina  no  shale  deposits  have  yet  been  developed  which  are  suitable 
for  the  manufacture  of  clay  products. 

As  clays  show  ail  gradations  from  the  purest  kaolins  to  the  most 
impure  brick  clays,  it  is  hard  to  draw  any  sharp  lines  of  division  be- 
tween the  kinds  of  clay  used  for  one  purpose  or  another,  and  conse- 
quently no  classification  is  here  given. 

As  before  stated,  kaolinite  forms  the  base  of  al]  clays,  and  the  rest 
of  the  clay  is  composed  chiefly  of  the  two  minerals  quartz  and  feld- 
spar. The  relative  proportion  of  these  three  can  not  be  calculated 
from  the  ordinary  analysis,  but  if  the  amount  of  residue  insoluble 
in  sulphuric  acid  and  sodium  hydroxide  be  determined,  and  this  latter 
analyzed  for  alumina,  potash  and  soda,  it  is  possible  to  calculate 
the  amount  of  clayd)ase,  quartz  and  feldspar  present  in  the  clay.  This 
determination  is  of  special  importance  in  the  case  of  clays  used  for  the 
manufacture  of  porcelain,  white  earthenware,  stoneware,  tiles,  and 
refractory  wares. 

The  amount  of  clay-base  may  vary  within  wide  limit-.  In  a  strictly 
pure  kaolin  it  should  theoretically  be  10(K,  but  seldom  exceeds  tuv,. 
On  the  other  hand,  it  may  get  as  low  as  5  or  10  per  cent.,  and  in  this 
instance  the  material  would  resemble  a  sand  more  than  clay.  The  per- 
centage of  feldspathic  detritus  is  seldom  large. 


14  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

In  kaolins  of  great  purity  the  clay  substance  consists  of  kaolinite,  but 
in  impure  clays  the  term  is  generally  taken  to  mean  the  finest  clay  par- 
ticles, viz.,  those  under  jjtq  inches  diameter.  In  impure  clays  the 
clay  substance,  which  may  contain  both  ferric  oxide  and  lime,  often 
forms  the  most  plastic  portion  of  the  mass. 

In  the  North  Carolina  clays  the  variations  in  clay  substance  and  free 
sand  (quartz  and  feldspar  with  some  mica)  are  shown  by  the  following 
extremes : 

Clay  substance. 

Washed  kaolin,  Webster  (53)   96.81  % 

Bottom  clay,  Prospect  Hall  (12)    85.02% 

Crude  kaolin,  Bosticks  Mills  (20)   47.14% 

Free  sand  (quartz  and  feldspar). 

Black  clay,  Prospect  Hall  (12)   15.05% 

Kaolin,  Bosticks  Mills  (20)    52.86%, 


CHAPTER  II. 

CHEMICAL  PEOPEKTIES  OF  CLAY. 

The  properties  of  clay  are  of  two  kinds,  (1)  chemical  and  (2)  phys- 
ical, and  the  action  of  clays  under  heat  is  not  dependent  on  one  class 
of  properties  alone,  but  upon  both  acting  together.  Two  clays  may 
correspond  closely  in  chemical  composition,  but  differ  in  their  phys- 
ical properties,  and  consequently  act  in  a  totally  different  way. 

Pure  clay,  as  previously  stated,  consists  of  the  mineral  kaolinite. 

This  is  a  white,  pearly  mineral,  crystallizing  in  the  monoclinic  system, 
the  crystals  presenting  the  form  of  small  hexagonal  plates.  Its  specific 
gravity  is  2.2  to  2.6,  and  its  hardness  is  2  to  2.5.  It  is  naturally  white 
in  color,  and  plastic  when  wet,  but  very  slightly  so.  A  microscopic 
examination  shows  the  plates  of  kaolinite  to  be  collected  in  little 
bunches,  which  if  broken  apart  by  grinding  increase  the  plasticity.1  If 
kaolin  be  formed  into  briquettes  of  the  same  shape  as  those  used  in  test- 
ing cement,  its  tensile  strength,  as  determined  by  pulling  these  bri- 
quettes apart  in  a  testing  machine,  is  usually  12  to  15  pounds  per  square 
inch — a  very  low  amount  when  compared  with  the  tensile  strength  of 
more  plastic  clays.  Kaolinite  is  practically  infusible,  as  much  so  as 
silica  or  magnesite,  but  a  slight  addition  of  fusible  impurities  immedi- 
ately lowers  its  refraetiveness. 

IMPURITIES   IN    CLAY. 

The  impurities  in  clay  are  silica,  iron  oxides,  lime,  magnesia,  potash, 
soda,  titanic  acid,  sulphuric  acid,  phosphoric  acid,  manganese  oxide  and 
organic  matter.2  They  are  generally  present  in  the  clay  in  the  form  of 
oxides,  silicates,  carbonates,  sulphates,  phosphates,  etc.  The  minerals 
present  in  clay  containing  these  impurities  may  be  feldspar,  quartz, 
limonite,  mica,  garnet,  hornblende,  augite,  calcite,  gypsum,  talc,  etc. 

The  impurities  in  a  clay  will  vary  in  effectiveness  according  to  the 
quantity  present  and  the  combination  in  which  they  exist.  Thus  cal- 
cium or  alkalies  if  present  as  silicates  may  serve  as  a  most  useful  I  lux. 
whereas  if  the  calcium  is  present  as  carbonate  it  may  be  very  injurious. 

The  impurities  found  in  clay  may  be  divided  into  two  classes  accord- 
ing to  their  effects:  (1)  fluxing  impurities,  and  (2)   non- fluxing  ones. 

1  The  Clays  of  New  Jersey,  N.  J.  Geol.  Survey,  1878.    G.  H.  Cook. 

2  All  of  these  impurities  are  seldom  present  in  the  same  clay. 


16  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

FLUXING   IMPURITIES. 

These  include  alkalies,  ferric  oxide,  lime,  magnesia  and  silica.  Their 
effectiveness  or  fluxing  action  is  in  the  order  given  above;  therefore,  of 
two  clays  having  the  same  physical  properties  and  the  same  total  per- 
centage of  fusible  impurities,  the  one  might  be  more  fusible  than  the 
other  on  account  of  having  a  larger  proportion  of  the  more  active  of  the 
fluxes  in  its  composition.  For  some  purposes  it  is  desirable  as  well  as 
necessary  that  the  percentage  of  fluxes  should  be  low,  not  only  for 
reasons  of  refractiveness,  but  also  to  prevent  discoloration  of  the  ware, 
as  when  the  clay  is  used  for  porcelain  manufacture.  On  the  other 
hand,  when  the  clay  is  to  be  used  for  paving  brick  or  sewer-pipe,  a  high 
percentage  of  fluxing  impurities  is  desirable  in  order  to  produce  a  vitri- 
fied body.  In  kaolins  the  fluxes  may  be  as  high  as  7^,  provided  they 
do  not  exert  a  coloring  action.  Thus  some  of  the  most  celebrated  por- 
celain kaolins  have  35$  of  feldspar,  which  means  about  5.5$  of  potash. 
In  fire-clay  4  to  5$  is  the  permissible  limit,  depending  on  the  physical 
properties.  For  paving  brick  and  sewer-pipe  the  total  fluxes  may  run 
as  high  as  16$. 

The  term  fluxing  impurities  should  not  be  misunderstood.  All  the 
substances  mentioned  below  as  exerting  a  fluxing  action  do  not  become 
effective  at  the  same  temperature.  Thus  quartz  is  a  flux  at  extremely 
high  temperatures,  while  feldspar  acts  at  a  lower  temperature,  and  iron 
or  lime  at  a  lower  one  still.  Furthermore  the  greater  the  amount  of 
feldspar  present,  the  lower  the  temperature  at  which  the  quartz  and 
kaolinite  act  on  each  other,  for  the  feldspar  when  fused  seems  to  play 
the  same  part  that  water  does  in  promoting  chemical  action  between 
two  substances  which  when  dry  do  not  act  upon  each  other. 

ALKALIES    IX    CLAY. 

The  alkalies  present  in  clays  may  be  of  two  kinds,  viz.:  the  fixed 
alkalies,  potash,  soda  and  lithia,  and  the  volatile  alkali,  ammonia. 

Ammonia. — This  substance  is  abundant  in  moist  clay,  and  is  ab- 
sorbed by  the  latter  with  great  avidity.  Indeed,  it  is  responsible  to  a 
large  extent  for  the  characteristic  odor  of  clay.1  If  the  ammonia 
remained  in  the  clay  it  would  act  as  a  strong  flux,  but  it  is  rendered 
harmless  for  the  simple  reason  that  it  passes  off  as  a  vapor  at  a  tem- 
perature considerably  below  dull  redness,  or  may  even  volatilize  with 
the  moisture  in  the  clay  during  the  early  stages  of  burning. 

The  fixed  alkalies,  potash,  soda,  and  lithia,  will  only  vaporize  at 
high  temperatures,  and  consequently  their  effect  must  be  taken  into  con- 
sideration in  all  stages  of  the  drying  and  burning.     Lithia  is  of  very 

1  F.  Senft,  Die  Thonsubstanzen,  p.  29. 


CHEMICAL    PROPERTIES    OF    CLAY.  17 

rare  occurrence  and  only  apt  to  be  present  in  the  rare  mica,  lepidolite; 
it  may  therefore  be  left  out  of  consideration. 

Potash  and  soda  are  present  in  almost  every  clay,  from  a  trace  up  to 
nine  or  ten  per  cent.,  with  an  average  of  one  to  three  per  cent. 

The  reason  for  this  variation  is  easily  apparent  when  we  consider  the 
composition  of  pure  clay  and  its  derivation.  Kaolinite,  it  will  be 
remembered,  contains  only  silica,  alumina  and  water,  whereas  orthoclase, 
the  common  feldspar,  has  nearly  l7fo  of  alkalies.  The  presence  in  the 
clay,  therefore,  of  varying  amounts  of  undecomposed  or  even  partly 
altered  feldspar  would  be  sufficient  to  account  for  the  alkalies  found  in 
greater  or  less  quantities  in  the  majority  of  samples  analyzed.  Aside 
from  the  feldspar,  the  only  common  rock-forming  mineral  containing 
alkalies  in  abundance  is  mica.  In  a  few  cases  potash  or  soda  may  be 
present  in  the  form  of  soluble  salts.  We  may,  therefore,  recognize  two 
sources  of  the  alkalies,  viz.,  soluble  and  insoluble  compounds. 

SOLUBLE     ALKALINE     COMPOUNDS. 

Soluble  alkaline  salts  are  very  frequently  present  in  clays,  though 
generally  in  very  small  quantities.  They  may  come  from  the  decom- 
position of  feldspar  (as  in  the  case  of  potassium  carbonate),  or  may  have 
been  introduced  by  percolating  surface  waters.  In  most  regions  the 
soluble  alkaline  compounds  are  unimportant  and  hardly  worth  atten- 
tion; but  in  areas  of  little  rainfall,  where  evaporation  exceeds  precipi- 
tation, they  become  concentrated  near  the  surface.  These  soluble  salts 
may  give  the  manufacturer  considerable  trouble.  Unless  decomposed 
in  burning  or  rendered  insoluble  in  some  way,  they  may  form  an 
unsightly  white  coating  on  the  surface  of  a  burned  brick  or  other  pro- 
duct. In  a  similar  manner  this  crust  may  interfere  with  the  formation 
of  a  salt  glaze  by  preventing  the  union  of  the  sodium  vapors  with  the 
silica  of  the  clay,  or  prevent  the  glaze  adhering  to  the  surface  of  pottery 
which  is  glazed  before  burning. 

Soluble  alkaline  sulphates  are  powerful  fluxes.  They  may  cause  blis- 
tering of  the  ware  if  the  clay  is  heated  sufficiently  high  to  decompose 
the  sulphate  and  permit  the  escape  of  sulphuric  acid  gases. 

In  some  clays  containing  sulphate  of  iron  the  latter  may  be  decom- 
posed by  chemical  reactions  taking  place  in  the  clay  and  sulphuric  acid 
set  free.  This  acid  is  apt  to  attack  the  alumina,  of  the  clay-base,  and, 
if  potash,  soda  or  ammonia  are  present,  give  rise  to  potash,  soda,  or 
ammonia  alum,  which  can  frequently  be  detected  by  tasting  the  clay. 

INSOLUBLE     ALKALINE     COMPOUNDS. 

The  minerals  feldspar  and  mica  forming  this  class  of  alkaline  salts  in 
clay   are   among   the   commonest   of  the  rock-forming   minerals.     The 


18  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

feldspars  are  silicates  of  alumina  and  potash,  or  alumina,  lime  and  soda. 
Orthoclase  is  the  only  species  furnishing  potash,  of  which  it  contains 
about  17$,  while  the  lime-soda  feldspars  have  from  4  to  12$  of  soda  de- 
pending on  the  species. 

The  orthoclase  is  by  far  the  commonest  of  the  feldspars,  and  next 
to  it  in  point  of  abundance  come  albite  and  oligoclase,  with  about  12$ 
and  9$  of  soda  respectively.  The  species  of  feldspars  present  in  a  clay 
may  have  some  bearing  on  its  refractiveness,  for  the  soda  feldspars  are 
more  fusible  than  the  potash  ones. 

The  micas  are  complex  silicates  of  aluminium  with  iron,  magnesium, 
and  potassium.  Muscovite,  the  commonest  species  of  the  group,  con- 
tains nearly  12$  of  potash  and  may  at  times  contain  a  little  soda. 

Feldspar  is  the  only  serious  source  of  alkalies  in  clays,  however,  for 
the  mica  is  not  always  present  in  very  large  amounts.  Mica  alone  is 
extremely  refractory,  being  unaffected  at  a  temperature  of  2550°  I\, 
while  feldspar  fuses  completely  at  2300°  F.1 

Alkalies,  on  account  of  their  fluxing  properties,  especially  if  in  the 
insoluble  form  as  silicates,  are  frequently  of  an  advantage,  as  they  serve, 
in  burning,  to  bind  the  particles  together  in  a  dense,  hard  body,  and 
permit  the  ware  being  burned  at  a  lower  temperature.  In  the  manu- 
facture of  porcelain,  white  granite  and  C.  C.  ware  (cream-colored  ware), 
the  alkalies  for  fluxing  are  added  to  the  body  in  the  form  of  feldspar, 
provided  the  kaolin  does  not  already  contain  a  sufficient  amount  of  this 
material.  Much  feldspar  is  mined  in  this  country  for  potters'  use,  all 
of  it  being  the  potash  feldspar. 

So  far  as  is  known,  the  alkalies  exert  no  coloring  influence  on  the 
burned  ware,  although  if  an  excess  of  feldspar  be  added  to  a  white 
burning  kaolin,  the  latter  may  exhibit  a  yellowish  tint  when  burned. 

In  the  North  Carolina  clays  the  combined  alkalies  (potash  and  soda) 
vary  from  .29$  in  clay  from  Spout  Springs  to  4.62$  in  brick  clay  from 
Wilkesboro.  The  average  is  1.50  to  2.5$.  The  washed  kaolins  usually 
contain  under  one  per  cent.  The  pottery  clays  of  North  Carolina  have 
from  0.68  to  2.82$. 

COMPOUNDS    OF    IRON    IN    CLAY. 

Aside  from  being  a  flux,  iron  oxide  is  also  the  great  natural  coloring 
agent  of  clays  in  both  their  raw  and  burned  state.  The  mineral  com- 
pounds which  may  serve  as  the  sources  of  iron  oxides  in  clays  are  as 

follows : 

Silicates:    Mica,  hornblende,  garnet,  etc. 
Oxides:  Limonite,  hematite,  magnetite. 
Sulphides:  Pyrite,  marcasite. 
Sulphates:    Melanterite. 
Carbonates:  Siderite. 

i  G.  Vogt,  Bull,  de  la  Soc.  Chim.  de  Paris  ;  and  Chem.  News,  1890,  p.  315. 


CHEMICAL    PROPERTIES    OF    CLAY.  19 

The  silicate  mineral,  mica,  is  missing  in  very  few  clays.  Of  the 
oxides,  limonite  and  hematite  are  frequent  impurities,  and  are  often 
introduced  from  the  surface  by  percolating  waters,  or  may  result  from 
the  decomposition  of  minerals,  such  as  garnet.  This  fact  is  noticeable 
in  some  of  the  less  pure  portions  of  the  kaolin  beds  at  Webster,  North 
Carolina.  The  iron  oxides  color  the  raw  clay  various  shades  of  red 
and  yellow.  Pyrite  is  frequently  present  in  clays,  especially  in  many 
stoneware  and  fire-clays,  its  yellow,  glittering  metallic  particles  being 
easily  recognizable.  When  disseminated  through  the  clay  in  small 
grains  it  may  be  difficult  to  separate  except  by  careful  washing;  but 
when  occurring  in  lumps,  popularly  known  as  "  sulphur  balls/'  it  is 
much  easier  to  extract.  If  the  finely  disseminated  pyrite  remained  in 
the  clay,  it  would  be  found  after  burning  that  the  clay  was  dotted  with 
fused  spots  of  silicate  of  iron.  Many  of  the  first  speckled  brick  so 
extensively  used  at  the  present  time  were  made  in  this  manner. 

The  pyrite  may  readily  become  oxidized  to  the  soluble  sulphate  of 
iron,  which,  if  present  in  sufficiently  large  amounts,  imparts  an  inky 
taste  to  the  clay.  Pyrite  being  such  a  strong  flux,  the  addition  of 
1-J  to  2$  by  weight,  according  to  Wipplinger,1  may  exert  a  noticeable 
effect  in  the  increase  of  its  fusibility. 

In  all  the  classes  of  iron  compounds  mentioned  above,  the  iron  is 
present  in  one  or  two  conditions,  viz.  as  a  ferrous  or  ferric  salt;  and 
the  fusibility  of  the  clay  depends  somewhat  on  this  condition,  ferrous 
salts  being  more  fusible  than  ferric  salts.  In  burning  any  clay  the 
ferrous  salt  will  be  changed  to  the  ferric  salt,  provided  the  action  of  the 
fire  is  oxidizing.  If  the  fire  exerts  a  reducing  action,  the  same  clay  will, 
under  these  conditions,  fuse  at  a  lower  temperature. 

Ferric  silicate  may  be  an  original  mineral  impurity  of  the  clay,  but 
many  ferric  compounds  in  clays  result  from  the  oxidation  of  ferrous 
carbonate  or  ferrous  hydrate  in  clay  which  has  been  introduced  in  solu- 
tion. The  presence  of  ferric  hydrate  in  clay  increases  its  absorptive 
power  for  gases  and  solutions.  On  burning,  the  hydrate  is  of  course 
converted  into  an  oxide. 

If  treated  to  an  oxidizing  fire,  the  presence  of  ferrous  salts  need  not 
therefore  be  considered,  provided  the  heat  is  raised  high  enough  to 
oxidize  them.  The  rapidity  with  which  the  temperature  is  raised  is 
important,  for  if  the  heat  is  raised  too  quickly  the  outer  portion  of  the 
clay  may  shrink  and  become  dense  before  the  air  has  had  time  to 
permeate  the  clay  and  oxidize  the  iron  in  the  centre  of  the  body.  This 
is  the  cause  of  black  cores  sometimes  seen  in  bricks  whose  surface  is 
red.  This  rapid  heating  may  also  bring  about  a  differential  shrinkage 
between  the  interior  and  exterior  of  the  brick  and  cause  cracking. 

1  Keramik,  p.  26. 


20  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Uiiburnecl  clays  may  be  yellow,  blue,  brown,  red  or  gray  in  color, 
depending  on  the  relative  amounts  of  ferrous  and  ferric  salts  present. 

The  same  variety  of  shades  and  colors  is  produced  in  burning.  Fer- 
rous oxide  (FeO)  alone  produces  a  green  color  when  burned,  while 
ferric  oxide  (Fe203)  alone  may  give  a  purple,  and  mixtures  of  the  two 
may  produce  yellow,  cherry-red,  violet,  blue  and  black,1  a  fact  which  is 
of  the  greatest  importance  to  manufacturers  of  unglazed  wares.  The 
more  intense  the  heat  the  deeper  the  color  produced  by  the  iron. 

Seger  2  found  that  combinations  of  ferric  oxide  with  silica  produced 
a  yellow  or  red  color,  while  similar  compounds  of  the  ferrous  salt  showed 
blue  and  green. 

The  black  coloration  by  iron  produced  by  hard  firing  is  often  to  be 
seen  on  breaking  open  the  arch  bricks  of  a  brick  kiln.  The  surface  of 
these  bricks  may  get  black,  due  to  the  dust  and  ashes  of  the  fire  sticking 
to  it. 

The  bleaching  of  the  iron  color  by  the  presence  of  lime  is  to  be  seen 
in  many  calcareous  clays,  as  described  under  lime.  It  may  sometimes 
happen,  however,  that  a  calcareous  clay  when  burned  does  not  become 
buff,  but  shows  a  red  surface,  as  if  there  were  no  lime  present  to  neu- 
tralize the  iron  color. 

In  such  an  instance  as  found  by  Seger,  the  core  of  the  brick  may 
show  the  expected  buff  color.  This  was  brought  about  by  the  sulphuric 
acid  vapors  from  the  fuel  uniting  with  the  lime  of  the  clay  to  form 
calcium  sulphate,  thus  preventing  its  union  with  the  ferric  oxide. 

The  percentage  of  ferric  oxide  permissible  or  desirable  in  a  clay 
depends  on  the  quality  of  the  latter.  Kaolins,  to  be  used  in  the  manu- 
facture of  white  ware,  should  have  under  1$  if  possible,  although  many 
with  1.5$  produce  excellent  results.  A  greater  percentage  might  be 
present,  provided  there  was  also  present  three  times  as  much  lime  to 
neutralize  its  color. 

If  a  kaolin  has  enough  ferric  oxide  to  produce  a  faint  yellowish  tinge 
when  burned,  by  burning  it  in  a  reducing  atmosphere  the  color  will  be 
bluish,  and  will  be  far  less  noticeable.  The  reduction  is  accomplished 
by  letting  less  air  into  the  kiln,  and  the  production  of  a  smoky  fire. 

The  North  Carolina  washed  kaolins  contain  from  .28$  to  1.86$;  the 
unwashed,  1.14$  to  1.86$;  the  pottery  clays  from  2.88.^  to  5.48$. 

The  total  range  of  ferric  oxide  in  the  seventy-three  samples  of  North 
Carolina  clays  which  were  tested  was  from  .28$  to  11.79^,  with  an 
average  of  1.5$  to  5$. 

LIME    IN    CLAYS. 

Lime  is  a  common  detrimental  or  fluxing  impurity  of  most  medium 
or  low  grade  clays.     It  may  be  present  in  one  of  three  conditions,  viz. : 

1  Keramik,  p.  258.  5  RotizUatt,  1874,  p.  16. 


CHEMICAL    PROPERTIES    OF    CLAY.  21 

a.  As  a  silicate,  such  as  in  the  feldspars. 

b.  As  a  simple  carbonate,  limestone  or  calcite,  or  in  the  form  of  a 
double  carbonate,  as  dolomite. 

c.  As  a  sulphate,  such  as  gypsum. 

The  first  two  of  these  are  primary  mineral  constituents  of  the  clay, 
the  third  is  of  secondary  origin  and  results  from  chemical  action  taking 
place  in  the  clay. 

The  presence  of  lime  as  a  silicate  in  clay  is  probably  the  form  in 
which  it  usually  occurs,  especially  if  the  clay  has  been  derived  wholly 
or  in  part  from  a  region  of  feldspathic  rocks.  The  common  feldspar, 
orthoclase,  contains  no  lime,  so  that  it  probably  comes  from  the  lime- 
soda  feldspars.  There  are  other  silicates  containing  lime,  but  their  pres- 
ence is  usually  more  difficult  to  prove  with  certainty. 

When  present  as  a  silicate,  lime  acts  as  a  flux,  but  it  is  less  liable  to 
exert  a  decolorizing  action  on  the  clay,  by  the  formation  of  a  double 
silicate  of  iron  and  lime,  except  at  higher  temperatures. 

Calcium  carbonate  is  very  common  in  clays  which  have  been  derived 
in  part  from  limestone  areas,  or  it  may  result  from  the  decomposition 
of  lime-bearing  feldspars.  Its  presence  may  be  usually  determined  by 
treating  the  clay  with  muriatic  acid,  which  produces  effervescence  if 
more  than  4  or  5$  of  calcium  carbonate  is  present. 

Lime  if  present  in  the  form  of  lumps  or  pebbles  is  very  injurious, 
and  should  be  removed  by  screening  or  washing.  Finely  divided  lime 
though,  if  not  present  in  too  large  amounts,  may  be  harmless.  Clays 
with  20  to  25$  of  calcium  carbonate  may  be  used  for  common  or  even 
pressed  bricks,  and  also  for  earthenware.  In  the  latter  case  the  same 
clay  can  often  be  utilized  for  glazing  the  pottery,  requiring  only  the 
addition  of  some  fluxes. 

EFFECT  ON  THE  BRICK  OF  CALCIUM  CARBONATE  IN  CLAY. 

When  occurring  as  carbonate  in  clay,  lime  becomes  far  more  injuri- 
ous. If  the  clay  is  under-burned,  the  calcium  carbonate  will  be  simply 
broken  up  into  carbon  dioxide  and  lime.  The  former  escapes,  but  the 
lime,  on  the  cooling  of  the  brick,  slakes,  that  is  to  say,  it  absorbs  water 
from  the  air,  and  swells,  thus  frequently  bursting  the  brick. 

If,  however,  the  clay  is  thoroughly  burned,  the  calcium  carbonate 
after  being  decomposed  unites  with  any  free  silicate  that  may  be 
present  and  forms  silicate  of  lime  or  probably  also  silicate  of  lime  and 
alumina.  If  iron  oxide  is  present,  the  lime  takes  it  also  into  combina- 
tion and  thereby  destroys  its  coloring  action,  giving  a  buff  product 
instead  of  a  red  one,  as  would  be  the  case  if  the  iron  oxide  remained 
free.  It  should  also  be  stated,  however,  that  a  low  percentage  of  iron 
oxide  in  the  clay  without  the  presence  of  lime  will  also  give  a  buff- 
colored  ware.     This  is  the  case  with  manv  stoneware  clays. 


22  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

In  high-grade  clays  large  amounts  of  lime  do  not  have  to  be  consid- 
ered, for  such  materials  cannot  be  used,  but  in  the  manufacture  of  build- 
ing brick,  or  pressed  brick,  terra-cotta,  etc.,  it  is  frequently  necessary  to 
use  a  clay  containing  large  percentages  of  lime,  either  from  necessity  or 
to  obtain  a  cream-colored  ware.  It  therefore  becomes  a  matter  of 
importance  to  know  how  much  lime  is  permissible  in  a  clay  for  this  pur- 
pose. In  general,  it  may  be  said  that  a  good  brick  can  be  made  from  a 
clay  containing  20  to  25$  of  calcium  carbonate,  provided  it  is  evenly 
distributed  through  the  clay  and  in  as  finely  a  divided  state  as  possible. 

Some  clays  contain  lime  in  angular  fragments  or  pebbles,  which  can 
be  frequently  removed  by  screening. 

Aside  from  lowering  the  fusibility  of  a  clay  to  a  marked  extent,  lime 
also  exerts  a  powerful  effect  on  its  shrinkage. 

Seger1  found  that  calcareous  or  marly  clays  required  usually  only 
20  to  24$  of  water  to  convert  them  from  a  dry  condition  into  a  workable 
paste,  whereas  other  clays  needed  28  to  35^  of  water  to  accomplish  the 
same  change.  Furthermore,  as  calcareous  clays  lost  not  only  combined 
water  but  also  carbon  dioxide  in  burning,  the  bricks  were  the  more 
apt  to  be  light  and  porous,  and  this  increased  with  the  amount  of  lime 
present.  They  also  shrink  much  less  than  other  clays  up  to  the  points 
of  incipient  fusion.  This  low  shrinkage  may  become  zero,  and  the 
brick  swell  instead  of  shrinking.  He  also  found  that  the  difference 
between  the  points  of  incipient  fusion  and  viscosity  was  so  small  that 
it  was  extremely  difficult  to  bring  a  kiln  of  bricks  made  from  calcareous 
clay  to  vitrification  without  melting  a  large  number. 

Seger  claims  that  the  presence  of  calcium  carbonate  and  ferric  oxide 
in  the  proportions  of  3:1  is  sufficient  to  produce  a  buff  color. 

Many  clays  contain  calcium  in  the  form  of  gypsum,  the  hydrated 
calcium  sulphate.  It  generally  originates  from  the  action  on  calcium 
carbonate  by  sulphuric  acid  obtained  by  the  oxidation  and  leaching  of 
pyrite  in  the  clay.  Gypsum  frequently  discloses  its  presence  by  the 
formation  in  the  clay  of  crystals  or  masses  of  its  transparent  variety, 
selenite.  It  also  not  uncommonly  occurs  in  masses  of  parallel  fibres 
filling  cracks  or  cavities  in  the  clay. 

It  serves  as  a  flux,  but  may  do  considerable  damage  in  burning  by 
its  disintegration,  the  sulphuric  acid  thus  set  free  causing  in  its  escape 
blisters  on  the  surface  of  the  wares. 

There  is  another  method  by  which  lime  may  be  introduced  into  clay, 
and  that  is  absorption.  This  may  occur  when  a  clay  deposit  rests  on 
a  limestone  or  marl  formation,  and  the  lime  being  taken  into  solution 
by  the  percolating  waters  is  soaked  up  by  the  clay.  In  this  event  the 
lower  layers  of  the  clay  would  be  more  calcareous  than  the  upper  ones. 

1  Gesammelte  Schrift,  p.  265. 


CHEMICAL    PROPERTIES    OF    CLAY.  23 

Few  of  the  North  Carolina  clays  are  very  calcareous.  Out  of  the 
seventy-three  samples  examined  the  lime  varied  from  .1$  in  the  clay 
at  Prospect  Hall  to  2.55$  in  Kirkpatrick's  clay  at  Greensboro.  This 
latter  is  exceptionally  high,  for  most  of  the  North  Carolina  clays  contain 
under  1$. 

Its  action,  therefore,  in  all  of  the  samples  tested  amounts  to  very 
little. 

Marly  clays  are  known  to  occur  in  the  coastal  plain  formation  near 
the  coast,  but  none  of  these  have  been  tested. 

MAGNESIA    IN    CLAYS. 

Magnesia  rarely  occurs  in  clays  in  the  same  quantity  as  lime;  in  fact, 
it  rarely  exceeds  2$.  In  the  North  Carolina  clays,  however,  of  which 
samples  were  examined  it  seldom  exceeds  .75$,  and  is  generally  present 
in  about  the  same  quantity  as  the  lime. 

Magnesia  may  be  derived  from  the  same  classes  of  compounds  as 
lime,  viz.  silicates,  carbonates  and  sulphates. 

The  silicates  are  probably  by  far  the  most  abundant  form  of  its  occur- 
rence in  clay  and  are  represented  by  the  minerals  mica,  chlorite,  and 
hornblende  (all  scaly  minerals)  containing  respectively  20-25$,  15-25$, 
and  15$  of  magnesia.  The  mica  scales  may  be  prominent  in  many 
clays,  and  chlorite  scales,  if  very  abundant,  might  even  tend  to  color 
the  clay  green.  Hornblende  is  mostly  present  in  clays  derived  from 
rocks  of  a  very  basic  composition  (that  is,  with  a  low  silica  percentage), 
and  the  same  may  be  said  of  pyroxene,  which,  however,  is  less  common 
than  the  hornblende. 

Dolomite,  the  double  calcium-magnesium  carbonate,  has  been  men- 
tioned under  the  description  of  lime  (p.  21). 

Magnesium  sulphate,  or  epsom  salts,  occurs  sparingly  in  clays.  It 
is  mostly  to  be  found  in  those  clays  where  sulphuric  acid,  set  free  by 
the  decomposition  of  pyrite,  has  attacked  magnesium  carbonates.  The 
presence  of  magnesium  sulphate  can  frequently  be  detected  by  the 
bitter  taste  which  it  imparts  to  the  clay. 

As  far  as  the  effects  of  magnesia  are  concerned  with  the  chemical 
properties  of  clay,  they  are  probably  the  same  as  lime.  This,  however, 
can  only  be  stated  with  a  reasonable  amount  of  certainty,  for  magnesia 
is  generally  present  in  such  small  amounts  that  its  actual  effect  cannot 
be  detected. 

NON-FLUXING   IMPURITIES. 

These  include  silica,  titanic  oxide,  organic  matter,  and  water.  Both 
silica  and  titanic  oxide  at  high  temperatures  are  fluxes. 


24  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

SILICA    IN    CLAYS. 

Chemical  analysis  distinguishes  two  classes  of  silica,  viz.  (1)  that  com- 
bined with  aluminium  in  kaolinite,  and  (2)  sand.  The  latter  includes 
quartz,  and  silica  in  combinations  with  various  bases  as  in  feldspar  and 
mica  (excluding  kaolinite).  The  two  kinds  of  silica  included  in  this 
second  class  are  insoluble  in  sulphuric  acid  and  sodium  hydroxide.  If 
this  residue  be  further  analyzed,  it  is  possible  to  calculate  the  amount  of 
silica  present  as  quartz  and  that  contained  in  the  clay  in  the  form  of 
feldspar  or  mica.  This  is  frequently  an  important  matter,  for  the  con- 
dition of  the  silica  may  influence  the  fusibility  of  the  clay  to  a  marked 
degree. 

Free  silica  or  quartz  is  present  in  all  clays  in  variable  amounts. 
Cook  *  found  a  minimum  of  0.2  of  one  per  cent.,  and  gives  5$  as  the 
average  in  the  Woodbridge  fire-clays.  Wheeler2  gives  the  minimum  as 
0.5  of  one  per  cent,  in  the  flint  clays,  and  the  sand  as  20  to  43$  in  the 
St.  Louis  fire-clays,  and  20  to  50$  in  the  Loess  clays. 

Twenty-seven  samples  of  Alabama  clays  contained  from  5  to  50$  of 
insoluble  residue,  mostly  quartz.8 

Seventy  North  Carolina  clays  had  from  15.05  to  70.43$  insoluble 
residue;  while  of  three  samples  of  which  a  rational  analysis  was  run 
the  percentage  of  sand  was  from  24.55  to  56.58$,  and  the  quartz  per- 
centage in  these  ran  from  16.58  to  49.06$,  and  the  feldspathic  detritus 
from  7.52  to  16.05$. 

Free  silica  is  considered  by  Bischof  *  to  exert  a  fluxing  action  at  high 
temperatures,  that  is,  over  2800°  F. 

The  most  important  effects  of  free  silica  and  sand  are  directed  towards 
the  physical  properties  of  clay.  They  lessen  the  plasticity,  diminish 
the  tensile  strength  and  also  the  shrinkage.  If  silica  is  present  in  ex- 
cess and  in  grains  of  large  size,  it  may  cause  the  clay  to  expand  in 
burning.  Quartz  in  fine  grains  lessens  the  shrinkage  less  than  when 
present  in  large  ones. 

TITANIUM    IN    CLAYS. 

Titanium  is  probably  of  widespread  occurrence  in  clay,  though  never 
present  in  great  quantity;  it  may  be  derived  from  rutile  (TiOo")  or 
ilmenite  (titaniferous  iron  ore).  It  was  formerly  looked  upon  as  a 
rare  element  and  a  non-detrimental  impurity,  but  this  idea  of  its  rarity 
has  resulted  from  the  fact  that  it  is  usually  overlooked  in  chemical 
analyses.  According  to  Seger,  it  is  often  present  in  clay  slates  and 
bauxites.  Its  effect  on  the  refractiveness  of  a  clay  has  always  been 
misunderstood,  although  its  action  was  considered  similar  to  silica. 

1  N.  J.  Clay  Rept.,  1878,  p.  213.  2  Mo.  G-eol.  Surv.,  XI,  p.  54. 

3  Forthcoming-  Bulletin  of  Alabama  Geological  Survey.        *  Die  Feuerfestcn  Tlwjie.  1896. 


CHEMICAL    PROPERTIES    OF    CLAY.  25 

Although  the  determination  of  titanium  in  clay  requires  no  difficult 
methods,  it  has,  as  a  rule,  not  been  determined  in  the  chemical  analyses 
of  clay  except  when  specially  desired. 

In  order  to  determine  definitely  what  the  effect  of  titanium  was, 
Seger  and  Cramer1  took  a  sample  of  Zettlitz  kaolin  (which  has  98.5$ 
of  clay  substance)  and  mixed  two  samples  of  it  with  respectively  5$  and 
10 fc  of  silica,  and  two  other  samples  of  the  kaolin  with  respectively  6.65$ 
and  13.3$  of  titanic  oxide.  These  samples  were  molded  into  pyramids, 
which  were  heated  to  a  temperature  above  the  fusing  point  of  Avrought 
iron  with  the  following  results : 

1.  Pure  Zettlitz  kaolin  burned  to  a  white,  sharp-edged,  dense  body. 

2.  100  pts.  kaolin  and  10%  silica  burned  white. 

3.  "      "         "         "      5%       " 

4.  "      "  "      6.65%  titanic  oxide  softened  in  heating  aud  showed  a 

blue  fracture. 

5.  "      "         "         '*      13.3%  titanic  acid  fused  to  a  deep  blue  enamel. 

It  will  therefore  be  seen  that  titanium  acts  as  a  flux  at  lower  tem- 
peratures than  silica,  and  calls  to  mind  the  fact  that  the  blue  color 
given  to  some  stoneware  clays  by  hard  firing  may  not  be  due  always  to 
iron  oxide. 

ORGANIC    MATTER    IN    CLAYS. 

This  is  commonly  noticed  in  many  clays  by  the  black  color  which  it 
imparts  to  them,  but  the  clay  may  also  be  colored  brown  or  blue  from 
the  same  cause. 

The  organic  matter  generally  consists  of  finely  divided  pieces  of  plant 
tissue,  or  large  pieces  of  stems  and  leaves,  which  settled  in  the  clay 
during  its  deposition.  All  surface  clays  contain  plant  roots  in  their 
upper  layers,  but  these  do  not  always  exert  a  coloring  effect. 

Clays  colored  by  organic  matter,  and  containing  no  iron,  burn  white 
as  the  plant  tissue  burns  off  at  a  bright  redness,  but  if  such  a  clay  is 
heated  too  quickly  the  surface  of  the  piece  becomes  dense  before  all  of 
the  organic  matter  has  had  time  to  escape  from  the  interior,  and  the 
latter  remains  dark  colored.  The  presence  of  iron  may  be  masked  by 
organic  matter,  so  that  the  clay  burns  red,  as-is_the  case  with  the  clays 
from  Prospect-  Hall,  on  the  Cape  Tear  river.  Organic  matter  is  sel- 
dom determined  separately  in  chemical  analysis,  but  its  quantity  may 
often  be  judged  approximately  from  the  relation  between  loss  on  igni- 
tion and  alumina. 

Organic  matter  exercises  the  important  property  of  increasing  the 
plasticity,  but  all  clays  having  organic  matter  are  not  necessarily  plastic, 
for  the  presence  of  much  sand  may  render  such  a  clay  very  Iran,  like 
the  Prospect  Hall  clays. 

1  Ges.  Schr.,  p.  411. 


26  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

In  the  weathering  of  clays,  organic  material,  by  its  oxidation  and 
consequent  evolution  of  carbonic  acid,  helps  to  break  up  the  clay. 

WATER    IN    CLAYS. 

The  water  in  clay  is  of  two  kinds: 

1.  Hygroscopic  water  or  moisture. 

2.  Chemically  combined  water. 

Moisture. — This  may  be  as  low  as  .5$  in  air-dried  clays  or  reach 
30$-40$  in  those  freshly  taken  from  the  bank.  In  the  air-dried  speci- 
mens of  the  North  Carolina  clays  it  ranged  from  .08 $  to  3.07$  in  the 
kaolins,  .45$  to  4.50$  in  the  sedimentary  clays,  and  .95$  to  1.90$  in  the 
residual  brick  clays. 

Air-drying  expels  most  of  the  moisture  in  a  clay,  and  this  is  accom- 
panied by  a  shrinkage  which,  in  70  samples  tested  from  North  Carolina, 
ranged  from  2$  to  13.3$.  Sandy,  coarse-grained  clays  usually  show  the 
least  shrinkage,  but  some  of  the  fine-grained  ones  may  act  in  a  similar 
manner.  The  amount  of  water  which  a  dry  clay  needs  in  order  to 
develop  an  easily  worked  paste  varies  from  12$-20$  in  lean  ones  and 
25$-35$  for  fat  clays.  The  samples  of  North  Carolina  clays  tested 
required  from  16$-40$.  The  more  water  that  a  clay  absorbs  the  more 
it  has  to  part  with  in  drying  and  the  greater  will  be  the  shrinkage.  If 
the  clay  is  fine-grained,  rapid  drying  may  cause  it  to  split  from  the 
active  disengagement  of  steam. 

In  the  manufacture  of  clay  products  the  moisture  is  expelled  by 
exposing  the  ware  to  the  sun  or  drying  it  in  heated  tunnels.  The  last 
portions  of  moisture  are  driven  off  in  the  early  stages  of  burning, 
known  as  water  smoking,  during  which  time  abundant  white  vapors 
can  be  seen  issuing  from  the  kiln. 

Combined  water  is  present  in  every  clay.  In  pure  kaolin  there  is 
nearly  14$  of  it.  In  other  clays  the  percentage  varies  with  the  amount 
of  clay-base  and  hydrates  present.  In  the  North  Carolina  clays  the 
loss  on  ignition  (which  practically  amounted  to  combined  water,  those 
containing  organic  matter  being  left  out)  varied  from  4.04$  to  13.40$  in 
the  washed  kaolins,  5.98$  to  9.00$  in  the  residual  clays,  and  4.17$  to 
11.08$  in  the  sedimentary  ones. 

Combined  water  is  driven  off  at  a  low  red  heat,  and  when  this  takes 
place  the  clay  begins  to  suffer  an  additional  loss  in  volume  or  shrinkage. 

It  is  a  curious  fact  that  while  the  amount  of  combined  water  does  not 
seem  to  stand  in  any  close  relation  to  the  plasticity  of  a  clay,  neverthe- 
less, when  once  driven  off,  the  clay  can  no  longer  be  rendered  plastic 
by  the  addition  of  water.  The  fire  shrinkage  in  the  North  Carolina 
clays  varied  from  2$-12$. 


CHEMICAL    PROPERTIES    OF    CLAY.  27 

METHODS  EMPLOYED  IN  MAKING  CLAY  ANALYSES. 

The  following  brief  statement  of  the  methods  employed  in  making 
the  analyses  of  clays  for  this  report  has  been  prepared  by  Dr.  Charles 
Baskerville,  by  whom  the  analyses  were  made: 

Moisture. — Two  grams  are  heated  in  a  platinum  crucible  at  100°  C. 
until  they  show  a  constant  weight.     The  loss  is  reported  as  moisture. 

Loss  on  Ignition  (combined  water,  and  sometimes  organic  matter, 
etc.). — The  crucible  and  clay  are  heated  with  a  blast  lamp  until  there 
is  no  further  loss  in  weight. 

Alkalies. — This  same  portion  of  clay,  which  has  been  used  for  de- 
termining moisture  and  loss,  is  treated  with  concentrated  sulphuric  and 
hydrofluoric  acids  until  it  is  completely  decomposed.  The  acids  are  evap- 
orated off  by  heating  upon  the  sand-bath.  The  cooled  crucible  is  washed 
out  with  boiling  water  to  which  several  drops  of  hydrochloric  acid  have 
been  added.  The  solution  after  being  made  up  to  about  five  hundred 
cubic  centimetres  is  boiled,  one-half  gram  ammonium  oxalate  added  and 
made  alkaline  with  ammonium  hydroxide;  the  boiling  is  continued  until 
but  a  faint  odor  of  ammonia  remains.  The  precipitate  is  allowed  to 
settle  and  is  separated  from  the  liquid  by  filtering  and  washed  three 
times  with  boiling  water.  The  filtrate  is  evaporated  to  dryness  and 
ignited  to  drive  off  ammonium  salts.  The  residue  is  treated  with  five 
cubic  centimetres  of  boiling  water,  two  or  three  cubic  centimetres  of 
saturated  ammonium  carbonate  solution  are  added  and  the  whole  is 
filtered  into  a  weighed  crucible  or  dish.  The  precipitate  is  washed 
three  or  four  times  with  boiling  water  and  the  filtrate  evaporated  to 
dryness.  Five  drops  of  sulphuric  acid  are  added  to  the  residue  and 
then  the  crucible  or  dish  is  brought  to  a  red  heat,  cooled  in  a  desiccator, 
and  the  alkalies  are  weighed  as  sulphates. 

To  separate  the  alkalies,  the  sulphates  are  dissolved  in  hot  water, 
acidified  with  hydrochloric  acid,  sufficient  platinum  chloride  added  to 
convert  both  the  sodium  and  potassium  salts  into  double  chlorides;  the 
liquid  is  evaporated  to  a  syrup  upon  a  water-bath,  eighty  per  cent, 
alcohol  added,  and  filtered  through  a  Gooch  crucible  or  upon  a  tared 
filter  paper.  The  precipitate  is  thoroughly  washed  with  eighty  per 
cent,  alcohol,  dried  at  100°  C.  and  weighed;  the  potassium  oxide  is  cal- 
culated from  the  double  chloride  of  potassium  and  platinum. 

When  magnesium  was  present  to  as  much  as  one-half  of  one  per  cent, 
the  magnesium  hydroxide  was  precipitated  with  barium  hydroxide  solu- 
tion, and  the  barium  in  turn  removed  by  ammonium  carbonate.  When 
the  amount  of  magnesium  was  less  than  the  amount  named,  this  por- 
tion of  the  ordinary  process  was  not  regarded  as  necessary. 

Silica. — Two  grams  of  clay  are  mixed  with  ten  grams  of  sodium  car- 
bonate and  one-half  gram  of  potassium  nitrate  and  brought  to  a  calm 


2S  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

fusion  in  a  platinum  crucible  over  the  blast  lamp.  The  melt  removed 
from  the  crucible  is  treated  with  an  excess  of  hydrochloric  acid  and 
evaporated  in  a  casserole  to  dryness  upon  a  water-bath,  and  heated  in 
an  air-bath  at  110°  C.  until  all  the  hydrochloric  acid  is  driven  off. 
Dilute  hydrochloric  acid  is  added  to  the  casserole  now,  and  the  solution 
brought  to  boiling  and  rapidly  filtered.^  The  silica  is  washed  thor- 
oughly with  boiling  water  and  then  ignited  in  a  platinum  crucible, 
weighed,  and  moistened  with  concentrated  sulphuric  acid.  Hydro- 
fluoric acid  is  cautiously  added  until  all  the  silica  has  disappeared.  The 
solution  is  evaporated  to  dryness  upon  a  sand-bath,  ignited  and  weighed. 
The  difference  in  weight  is  silica. 

Iron  Sesquioxide.- — The  filtrate  from  the  silica  is  divided  into  equal 
portions.  To  one  portion  in  a  reducing  flask  is  added  metallic  zinc  and 
sulphuric  acid.  After  reduction  and  filtration  to  free  the  liquid  from 
undissolved  zinc  and  carbon,  the  iron  is  determined  by  titration  with  a 
standard  solution  of  potassium  permanganate. 

Aluminium  Oxide. — To  the  second  portion,  which  must  be  brought 
to  boiling,  ammonium  hydroxide  is  added  in  slight  excess,  the  boiling 
continued  from  two  to  five  minutes,  the  precipitate  allowed  to  settle 
and  then  caught  upon  the  filter,  all  the  chlorides  being  washed  out  with 
boiling  water.  The  precipitate  is  ignited  and  weighed  as  a  mixture  of 
aluminium  oxide  and  iron  sesquioxide.  The  amount  of  iron  sesqui- 
oxide already  found  is  taken  from  this  and  the  remainder  reported  as 
alumina. 

Calcium  Oxide.— -The  filtrate  from  the  precipitate  of  iron  and  alum- 
inium hydroxides  is  concentrated  to  about  two  hundred  cubic  centi- 
metres, and  the  calcium  precipitated  in  a  hot  solution  by  adding  one 
gram  of  ammonium  oxalate.  The  precipitate  is  allowed  to  settle  dur- 
ing twelve  hours,  filtered  and  washed  with  hot  water,  ignited  and 
weighed  as  calcium  oxide.  When  the  calcium  is  present  in  notable 
amounts,  the  oxide  is  converted  into  the  sulphate  and  weighed  as  such. 

Magnesium  Oxide. — The  filtrate  from  the  calcium  oxalate  precipi- 
tate is  concentrated  to  about  one  hundred  cubic  centimetres,  cooled  and 
the  magnesium  precipitated  by  means  of  hydrogen  disodium  phosphate 
in  a  strongly  alkaline  solution,  made  so  by  adding  ten  cubic  centimetres 
of  ammonium  hydroxide  (0.90  sp.  gr.).  The  magnesium  ammonium 
phosphate,  after  standing  over  night,  is  caught  upon  an  ashless  filter, 
washed  with  water  containing  at  least  five  per  cent,  ammonium  hydrox- 
ide, burned  and  weighed  as  magnesium  pyrophosphate. 

The  insoluble  residue  is  determined  by  digesting  two  grams  of  clay 
with  twenty  cubic  centimetres  of  dilute  sulphuric  acid  for  six  or  eight 
hours  on  a  sand-bath,  the  excess  of  acid  being  finally  driven  off.  One 
cubic  centimetre  of  concentrated  hydrochloric  acid  is  now  added  and 


CHEMICAL    PROPERTIES    OF    CLAY.  29 

boiling  water.  The  insoluble  portion  is  filtered  off,  and  after  being 
thoroughly  washed  with  boiling  water  is  digested  in  fifteen  cubic  cen- 
timetres of  boiling  sodium  hydroxide  of  ten  per  cent,  strength.  Twenty- 
five  cubic  centimetres  of  hot  water  are  added  and  the  solution  filtered 
through  the  same  filter  paper,  the  residue  being  washed  five  or  six 
times  with  boiling  water.  The  residue  is  now  treated  with  hydro- 
chloric acid  in  the  same  manner  and  washed  upon  the  filter  paper,  and 
free  from  hydrochloric  acid,  is  burned  and  weighed  as  insoluble  residue. 

A  portion  of  this  is  treated  as  the  original  clay  for  silica,  aluminium 
oxide,  and  iron  oxide.  Another  portion  is  used  for  the  determination 
of  the  alkalies  in  the  insoluble  residue. 

Titanic  Oxide. — One-half  gram  clay  is  fused  with  five  grams  potas- 
sium bisulphate  and  one  gram  sodium  fluoride  in  a  spacious  platinum 
crucible.  The  melt  is  dissolved  in  five  per  cent,  sulphuric  acid.  Hy- 
drogen dioxide  is  added  to  an  aliquot  part  and  the  tint  compared  with 
that  obtained  from  a  standard  solution  of  titanium  sulphate. 

Sulphur  (total  present). — The  sulphur  is  determined  by  fusing  one- 
half  gram  of  clay  with'  a  mixture  of  sodium  carbonate,  five  parts,  and 
potassium  nitrate,  one  part.  The  melt  is  brought  into  solution  with 
hydrochloric  acid.  The  silica  is  separated  by  evaporation,  heating 
resolution,  and  subsequent  filtration.  Hydrochloric  acid  is  added  to  the 
filtrate  to  at  least  five  per  cent,  and  the  sulphuric  acid  is  precipitated  by 
adding  barium  chloride  in  sufficient  excess,  all  solutions  being  boiling 
hot.  The  barium  sulphate  is  filtered  off  and  washed  with  hot  water, 
burned  and  weighed  as  such. 

Ferrous  Oxide  is  determined  by  fusing  one-half  gram  clay  with  five 
grams  sodium  carbonate,  the  clay  being  well  covered  with  the  car- 
bonate, the  top  being  upon  the  crucible.  The  melt  is  dissolved  in  a 
mixture  of  dilute  hydrochloric  and  sulphuric  acids  in  an  atmosphere 
of  carbon  dioxide.  The  ferrous  iron  is  determined  at  once  by  titration 
with  a  standard  potassium  permanganate  solution. 

The  rational  analysis  is  made  from  the  results  obtained  by  the  chem- 
ical analysis  in  the  following  way:  The  alumina  found  in  the  portion 
insoluble  in  sulphuric  acid  and  sodium  hydroxide  is  multiplied  by 
3.51.  This  factor  has  been  found  to  represent  the  average  ratio  be- 
tween alumina  and  silica  in  orthoclase  feldspar;  therefore  the  product 
just  obtained  would  represent  the  amount  of  silica  that  would  be  presenl 
in  undecomposed  feldspar.  The  sum  of  this  silica  with  the  alumina. 
ferric  oxide  and  alkalies  equals  the  "  felclspathic  detritus.''  The  dif- 
ference between  silica  as  calculated  for  feldspar  and  the  total  silica  in 
the  insoluble  portion  represents  the  "  quartz "  or  "  free  sand."  The 
difference  between  that  portion  of  the  sample  insoluble  in  sulphuric 
acid   and   sodium  hydroxide   and   the   total   represents   the   "clay   sub- 


30  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

stance."  The  method  of  analysis  used  to  determine  the  mineralogical 
character  of  the  clay  is  called  the  rational  method,  and  when  carried 
out  in  its  simplest  form,  determines  the  amount  of  clay  substance  or 
kaolinite,  quartz,  and  feldspar  present  in  the  clay.  If  carried  out  more 
completely  it  enables  us  to  calculate  the  amount  of  calcite  or  limestone 
(calcium  carbonate),  iron  oxide  and  even  mica  in  the  clay. 

THE    RATIONAL   ANALYSIS   OF    CLAY. 

In  the  ordinary  or  ultimate  quantitative  analysis  of  clay  the  latter 
is  regarded  as  being  composed  of  a  given  number  of  elements  or  oxides 
of  them,  in  given  amounts,  but  gives  no  clue  as  to  the  condition  in 
which  these  substances  exist,  viz.,  whether  they  are  present  as  oxides, 
silicates,  carbonates,  etc.,  a  point  which  it  is  often  of  the  greatest  im- 
portance to  know.  Thus,  as  pointed  out  under  calcium  (Chemical  Prop- 
erties of  Clay),  if  this  substance  is  present  as  a  carbonate  it  may  be 
extremely  injurious,  but  if  combined  with  silica  in  the  form  of  feld- 
spar it  is  beneficial,  serving  as  a  binding  material  (p.  21).  Or,  again, 
the  ultimate  analysis  does  not  point  out  the  condition  of  the  silica, 
whether  present  as  quartz  (serving  to  lessen  the  shrinkage)  or  as  a  con- 
stituent of  feldspar  (serving  as  a  flux).  A  high  percentage  of  total 
silica  in  an  ultimate  analysis  may  be  caused  by  an  excess  of  feldspar 
and  not  always  by  quartz. 

The  inferences  which  may  be  drawn  from  the  ultimate  analysis  of  a 
clay  are: 

1.  It  may  be  said  in  general  that  the  greater  the  amount  of  ferric 
oxide  in  a  clay  the  deeper  red  it  will  burn  at  any  given  temperature. 
Small  percentages  of  ferric  oxide  will  only  color  the  clay  yellow. 

2.  We  can  see  from  the  ultimate  analysis  whether  there  is  sufficient 
lime  present  to  counteract  the  effect  of  the  feme  oxide. 

3.  It  is  possible  to  gain  an  approximate  idea  of  the  fusibility  of  the 
clay  from  the  total  fluxes  present,  and  also  to  see  whether  it  is  the 
weaker  or  more  powerful  fluxes  that  are  present. 

4.  A  very  high  silica  percentage  generally  indicates  a  sandy  clay. 

5.  Clays  high  in  alumina  and  combined  water  as  a  rule  shrink  con- 
siderably in  burning. 

There  are,  however,  many  physical  properties  which  the  ultimate 
analysis  does  not  explain,  because  they  are  dependent  largely  on  the 
mineralogical  composition. 

It  frequently  happens  that  two  clays  show  very  close  chemical  com- 
position, but  act  entirely  unlike,  and  the  explanation  is  almost  self- 
evident,  viz.,  that  the  elements  present  in  both  clays  are  differently 
combined. 

The  following  table  of  analyses  illustrates  this,  viz. : 


CHEMICAL    PROPERTIES    OF    CLAY.  31 

1.  That  clays  with  the  same  ultimate  composition  may  show  a  dif- 
ferent rational  composition  (see  analyses  a  and  b  below). 

2.  That  clays  may  agree  in  both  their  ultimate  and  rational  analysis 
(see  b  and  c  below),  but  this  is  not  very  frequent: 


Silica   47.60 

Alumina    34.00 

Ferric  oxide 1.30 

Lime    trace 

Magnesia    .50 

Alkalies    3.00 

Loss  on  ignition   13.60 

Total    100.00 

Clay  substance    88.34 

Quartz    8.95 

Feldspar    2.73 


b. 

c. 

46.61 

46.82 

36.47 

38.49 

2.81 

1.09 

.14 

trace 

1.44 

1.40 

12.80 

12.86 

100.17 

100.G6 

96.08 

96.55 

1.93 

2.30 

1.99 

1.15 

100.02  100.00  100.00 

The  practical  bearing  of  the  rational  analysis  has  thus  far  been 
chiefly  for  those  branches  of  the  clay-working  industry  using  mostly 
materials  of  considerable  purity,  as  in  the  manufacture  of  porcelain, 
white  earthenware,  fire-bricks,  glasspots  and  encaustic  tiles;  and  its 
importance  lies  in  the  fact  that  two  bodies  having  the  same  rational 
composition  will  usually  act  pretty  much  alike.  That  is  to  say,  that 
other  things  being  equal,  they  will,  for  instance,  usually  have  the  same 
shrinkage  in  burning. 

In  the  manufacture  of  porcelain  the  body  generally  consists  of  a  mix- 
ture of  kaolin,  quartz  and  feldspar.  Suppose  that  the  mixture'  has  60 
parts  of  feldspar  and  200  parts  of  kaolin,  the  latter  having  the  rational 
composition  of  the  Wests  Mill,  1ST.  C,  material,  viz.: 

Clay  substance,  83.39;  quartz,  14.98;  feldspar,  1.58. 

This  would  give  us  a  mixture  with  rational  composition  of: 

Clay  substance,  60.32;  quartz,  11.40;  feldspar,  24.30. 

If  now  for  the  Wests  Mill  kaolin  we  desired  to  substitute  that  from 
near  Bostick  having: 

Clay  substance,  54.30;  quartz,  43.85;  feldspar,  1.S2, 

and  used  the  same  amount  as  we  did  of  the  Wests  Mills  material,  we 
should  get  a  mixture  having: 

Clay  substance,  41.77;  quartz,  33.31;  feldspar,  20.3<>. 


32  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

This  mixture  having  less  feldspar  and  clay  substance,  but  more 
quartz,  would  probably  show  less  plasticity  and  less  shrinkage.  Know- 
ing,  however,  the  rational  composition  of  the  Bostick  kaolin,  it  is  per- 
fectly easy  to  add  it  in  such  proportions  as  will  keep  our  mixture  of  the 
same  composition. 

In  the  manufacture  of  tiles,  where  one  clay  body  is  pressed  on  to 
another,  it  is  highly  essential  that  the  two  should  have  the  same  shrink- 
age to  prevent  cracking  during  the  burning  and  cooling. 

Experiments  tend  to  show  that  if  the  two  bodies  have  the  same 
rational  composition  their  shrinkages  will  be  about  the  same,  provided 
there  is  not  much  difference  in  the  coarseness  of  their  grain.  In  porce- 
lain and  white  earthenware  manufacture  the  clays  are  ground  so  fine 
that  this  point  does  not  come  into  consideration. 

A  rational  analysis  has  been  made  of  all  the  I^orth  Carolina  kaolins 
tested,  and  in  the  other  clays  the  insoluble  residue  (quartz  and  feldspar 
combined)  was  determined. 


CHAPTER  III. 

PHYSICAL  PKOPERTIES  OF  CLAY. 

These  are  fully  as  important  as  the  chemical  ones,  and  sometimes 
more  so.  In  Germany  the  labors  of  Seger,  Bischof,  Olschewsky  and 
others  have  brought  forth  the  significance  which  the  physical  properties 
of  clays  have,  and  in  this  country  the  work  of  Orton  and  Wheeler  has 
corroborated  them  in  many  details. 

Chemical  analysis  alone  cannot  be  used  as  a  basis  of  comparison,  but 
the  physical  characters  must  also  be  taken  into  consideration. 

While  the  list  of  physical  properties  may  be  made  of  considerable 
length,  there  are  a  number  which  are  of  special  importance  and  will 
be  considered  herewith.  These  are  plasticity,  fusibility,  shrinkage,  ten- 
sile strength,  slaking,  absorption,  density. 

PLASTICITY   IN   CLAYS. 

This  is  one  of  the  most  important  properties  of  clays,  for  it  permits 
their  being  molded  into  any  desired  form,  which  they  subsequently 
retain. 

Plasticity  in  clays  is  exceedingly  variable.  Those  possessing  little 
plasticity  are  called  "  lean/7  while  those  which  are  highly  plastic  are 
known  as  "  fat "  clays. 

The  cause  of  plasticity  was  for  a  long  time  supposed  to  be  directly 
■connected  with  the  hydrated  silicate  of  alumina,  or  kaolinite,  and  clays 
high  in  kaolinite  were  said  to  be  very  plastic  and  vice  versa.  This  is 
plainly  not  so,  as  any  series  of  clays  tested  will  demonstrate. 

Pure  or  nearly  pure  kaolins  are  very  lean,  while  clays  low  in  alumina 
may  be  highly  plastic.  )  This  may  be  shown  by  a  few  examples  drawn 
from  the  North  Carolina  clays  tested,  mentioning  first  that  the  tensile 
strength  of  a  clay  (as  will  be  explained  later)  is  closely  related  to  its 
plasticity. 

The  examples  to  illustrate  this  point  are  as  follows : 

Tensile  strength  in 
Per  cent,  of  pounds  per  sq.  in. 

Alumina.       Average.     Maximum. 

Lower  clay,  Roanoke  Rapids  (3) 16.09  200  218 

Washed  kaolin  (53)   40.61  20  22 

Clay,  Spout  Springs  (17) 32.51  24  29 

Prof.  G-.  H.  Cook1  considered  that  plasticity  was  due  to  a  plate  struc- 

1  N.  J.  Geol.  Survey,  Kept,  on  Clays,  1878. 


3-i  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

ture  present  in  the  clay,  the  plates  sliding  over  each  other  and  thus 
permitting  mobility  of  the  mass  without  cracking.  As  kaolinite  is  prac- 
tically the  only  plate-like  mineral  omnipresent  in  the  clay,  the  simple 
plate  theory  does  not  seem  entirely  sufficient. 

Olschewsky'1  was  probably  the  first  to  suggest  that  the  plasticity  and 
cohesion  of  a  clay  were  dependent  on  the  interlocking  of  the  clay  par- 
ticles and  kaolinite  plates,  and  in  this  connection  used  the  briquette 
method  of  testing  the  plasticity  or  rather  obtaining  a  numerical  expres- 
sion for  it,  by  determining  the  tensile  strength  of  the  air-dried  clay. 

The  more  recent  experiments  of  W.  Aleksiejew  and  P.  A.  Cremiats- 
chenski  on  the  Russian  clays2  show  that  plasticity  is  not  only  due  to 
the  interlocking  of  the  clay  particles,  but  also  varies  with  the  fineness 
of  the  grain,  the  extreme  coarse  and  fine  ones  both  having  less  plas- 
ticity. 

In  this  country  Wheeler's  work  on  the  Missouri  clays  has  substan- 
tiated these  views.3 

Experiments  by  the  writer  on  the  Alabama  clays*4  corroborate  these 
results  still  further,  and  the  tests  of  the  Xorth  Carolina  ones  also  point 
in  the  same  direction.  The  clays  southeast  of  Spout  Springs,  for  ex- 
ample, which  are  very  fine-grained,  plainly  show  the  lessening  effect 
on  the  tensile  strength. 

Whether,  however,  the  greatest  tensile  strength  depends  on  the  pres- 
ence of  particles  of  certain  size,  or  a  mixture  of  different  sizes,  and,  if 
so,  within  what  limits  these  sizes  must  be,  is  still  to  be  determined. 

Plasticity,  whatever  may  be  its  exact  cause,  is  an  important  property 
from  a  commercial  standpoint,  for  it  facilitates  the  molding  or  burning 
of  the  wares  without  cracking. 

The  amount  of  water  required  to  develop  the  maximum  plasticity 
varies.  If  too  little  is  added,  the  clay  cracks  in  molding  and  is  stiff  and 
hard  to  work.  If  too  much  water  is  used,  the  paste  becomes  soft  and 
retains  its  shape  with  difficulty.  Lean  clays  usually  require  less  water 
to  produce  a  workable  paste  than  fat  ones. 

TENSILE   STRENGTH   OF   CLAYS. 

To  state  that  the  plasticity  of  a  clay  is  lean,  fair,  good,  or  high  is 
necessarily  only  approximate  and  unsatisfactory,  and  a  method  by  which 
the  degree  of  plasticity  can  be  expressed  accurately  is  much  to  be  pre- 
ferred. 

Various  methods  for  testing  the  plasticity  of  a  clay  have  been  devised, 
but  as  most  of  them  are  practically  useless,  if  for  no  other  reason  than 

1  Topf .  w.  Zieg\.  1882,  No.  29. 

2  Zap.  imp.  russk.  techn.  obschtsch.,  1896,  XXX,  pt.  6-7. 

3  Mo.  Geo!.  Surv.,  XI,  1897,  p.  102. 

4  The  Clay-working  Industry  in  1896, 18  Ann.  Rept.  U.  S.  Geol.  Surv.,  pt.  V.  p.  1129. 


PHYSICAL    PROPERTIES    OF    CLAY.  35 

that  they  are  largely  influenced  by  the  personal  equation,  their  discus- 
sion need  not  be  gone  into  here,  and  any  one  desiring  to  look  them  up 
is  referred  to  C.  Bischof's  work,  "  Die  Feuerfesten  Thone." 

Two  methods,  however,  approach  the  requirements: 

The  first  consists  in  forming  the  clay  into  a  bar  of  known  section  and 
then  noting  the  load  required  to  crossbreak  it.1 

The  second,  devised  by  Olschewsky,2  consists  in  molding  the  clay  into 
briquettes  of  the  same  shape  as  those  used  in  testing  cement,  allowing 
them  to  air-dry,  and  then  pulling  them  apart  in  a  cement  testing  ma- 
chine, noting  the  number  of  pounds  pull  required.  Before  breaking, 
the  cross-section  of  the  briquette  must  be  carefully  measured  and  the 
tensile  strength  per  square  inch  calculated,  as  the  clay  shrinks  in  drying. 
This  is  a  perfectly  rational  method  and  supposes  that  as  plasticity  is 
dependent  on  the  interlocking  of  the  particles,  the  tensile  strength  will 
naturally  stand  in  direct  relation  to  it.  Even  though  it  is  not  yet  cer- 
tain that  this  is  the  cause  of  plasticity,  still  it  is  certain  that  with  increase 
in  plasticity  there  is  a  rise  in  the  tensile  strength. 

In  the  North  Carolina  clays  the  tensile  strength  varied  from  5  lbs. 
per  sq.  in.  in  a  Webster  kaolin  to  220  lbs.  per  sq.  in.  in  a  brick  clay 
from  Greensboro. 

The  residual  clays  tested  were  all  of  low  tensile  strength. 

The  clays  were  all  ground  to  pass  through  a  30-mesh  sieve  before 
being  molded  into  the  briquettes. 

SHRINKAGE    OF   CLAYS. 

The  variable  shrinkage  of  clays  in  drying  has  already  been  mentioned 
in  the  discussion  of  water  in  clays.  The  amount  of  shrinkage  depends 
somewhat  on  the  amount  of  water  absorbed  or  the  porosity  of  the  clays. 
But  coarse-grained  clays  may  absorb  much  water  and  yet  shrink  com- 
paratively little.  Having  larger  pores,  they  will  permit  the  water  to 
escape  more  rapidly,  and  hence  can  often  be  dried  quicker  than  fine- 
grained ones,  from  which  the  water  on  account  of  the  smallness  of  the 
pores  cannot  escape  so  quickly. 

If  fine-grained  clays  are  dried  rapidly,  the  surface  shrinks  quicker 
than  the  interior,  and  cracking  may  ensue,  especially  if  the  clay  ha-  a 
low  tensile  strength. 

The  air  shrinkage  begins  as  soon  as  the  clay  is  molded  and  set  out 
in  the  sun  or  put  in  a  hot  tunnel  to  dry,  and  continues  until  the 
moisture  is  driven  off. 

The  fire  shrinkage  generally  commences  when  the  combined  water 
begins  to  pass  off,  or  about  1200°  F.  It  varies  just  as  the  air  shrinkage 
did. 

1  P.  Jochem,  Zeitscb.  der  Verein  deutech.  Trig.,  18P5.  -  Topi".  Zeit.,  1882,  No.  -'•:. 


36  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

In  the  North  Carolina  clays  the  fire  shrinkage  was  from  2-12$,  with 
an  average  of  4-6$. 

The  fire  shrinkage  is  influenced  by  several  conditions,  viz.  amount 
of  combined  water,  organic  matter,  and  sand.  The  fire  shrinkage  in- 
creases with  the  amount  of  organic  matter  and  combined  water  in  the 
clay.  Sand  diminishes  the  shrinkage.  Lime  has  the  same  tendency 
and  may  even  make  the  clay  swell  a  little.  Clays  containing  a  large 
amount  of  feldspar,  will,  instead  of  showing  a  steady  shrinkage  up  to 
the  temperature  of  complete  vitrification  or  sintering,  often  exhibit  a 
temporary  increase  of  volume  when  the  fusing  point  of  the  feldspar 
(about  2300°  F.)  is  reached. 

Between  the  points  at  which  the  moisture  has  ceased  coming  off  and 
that  at  which  the  combined  water  begins  to  escape,  the  clay  shrinks 
little  or  none  at  all.  Consequently  in  firing  a  clay  the  heat  can  be 
raised  rapidly  between  these  two  points,  but  above  and  below  them  it 
must  proceed  slowly  to  prevent  cracking  the  ware. 

FUSIBILITY   OF   CLAYS. 

In  the  heating  of  a  clay,  or  subjecting  it  to  a  gradually  increasing 
temperature,  it  not  only  shrinks  but  begins  to  harden.  After  the 
moisture  has  been  driven  off  the  clay  bears  some  handling  and  is  mod- 
erately hard,  but  can  be  scratched  by  the  finger-nail. 

Accompanying  the  second  shrinkage  of  the  clay,  beginning  at  a  dull 
red  heat,  there  comes  an  increase  in  hardness  and  density,  and  at  a 
temperature  of  from  1500°  to  2100°  F.,  depending  on  the  clay,  it  becomes 
very  dense,  the  individual  particles  are  barely  recognizable,  and  the 
clay  cannot  be  scratched  with  a  knife.  It  is  still  porous,  however.  This 
is  the  point  of  incipient  fusion.  With  an  increase  in  the  temperature 
of  from  50°  to  200°  F.,  depending  on  the  clay,  an  additional  amount  of 
shrinkage  occurs.  The  clay  becomes  hard,  dense,  impervious,  the  par- 
ticles are  no  longer  recognizable,  and  the  maximum  shrinkage  has  been 
attained.  This  is  the  point  of  vitrification  or  sintering.  "With  a 
further  similar  rise  in  temperature  the  clay  becomes  viscous  or  flows. 

These  three  stages  are  not  sharply  marked,  but  with  a  little  practice 
the  eye  can  detect  the  condition  which  the  burned  clay  has  reached. 
With  few  exceptions,  the  point  of  vitrification  seems  to  be  midway 
between  incipient  fusion  and  viscosity.  The  difference  in  temperature 
between  these  two  points  varies  from  75°-100°  F.  in  calcareous  clays, 
up  to  400°  or  more  in  the  purer  ones.  Indeed,  the  majority  of  clays 
show  a  difference  of  300°-400°  F.  between  incipient  fusion  and  viscosity. 

The  practical  value  of  this  property  is  at  once  apparent,  for  many 
clays  require  to  be  heated  to  vitrification,  and  the  greater  the  margin 
between  this  point  and  viscosity  the  better,  for  a  kiln  cannot  be  man- 
aged within  very  narrow  limits  of  temperature. 


PHYSICAL    PROPERTIES    OF    CLAY.  37 

TEMPERATURE   AT  WHICH  CLAY  FUSES. 

It  may  be  said  in  general  that,  other  things  being  equal,  the  fusi- 
bility of  a  clay  will  increase  with  the  amount  of  fluxes. 

This  is  only  to  be  regarded  as  an  approximate  statement,  for  all  the 
fluxing  impurities  do  not  act  with  the  same  intensity. 

If  the  fluxes  are  the  same,  a  fine-grained  clay  will  fuse  at  a  lower 
temperature  than  a  coarse-grained  one,  because  in  a  clay  with  fine  grain 
the  particles  are  closer  together,  and  can  interact  better  chemically  when 
they  become  softened  by  the  heat.  This  fact  may  be  brought  out  by  a 
comparison  of  the  pipe-clay  from  the  first  pit  at  Pomona  and  that  at 
Spout  Springs. 

The  former  is  coarse-grained,  and,  though  containing  5.10$  of  fluxes, 
only  vitrifies  at  2250°  F.,  while  the  latter,  with  only  3.81$  total  fluxes, 
vitrifies  at  2150°  because  it  is  very  fine-grained. 

Several  attempts  have  been  made  to  express  the  relative  fusibilities 
of  clays  numerically,  but  none  of  them  are  wholly  satisfactory,  as  they 
do  not  give  a  series  of  numbers  expressing  the  relative  fusibilities  of 
different  clays,  which  stand  in  the  same  order  as  the  fusibilities  them- 
selves. 

Until  this  can  be  done  such  formulae  have  no  definite  value,  and,  in 
any  case,  it  is  more  satisfactory  to  know  the  actual  temperature  of  fusion 
of  a  clay  than  to  express  it  in  relative  terms. 

Bischof 1  assumed  that  refractoriness  of  a  clay  is  directly  as  the  square 
of  the  alumina  and  inversely  as  the  silica  and  fluxes.  He  therefore 
deduced  the  formula  in  which  F.  Q.  stands  for  "  Refractory  quotient." 

v  n         fAl2OsV 
1-^-  —  Si02XRO" 

This  only  holds  good  for  comparing  clays  of  the  same  fineness.   When 
there  is  a  variation  in  this  the  formula  no  longer  holds  good. 
Wheeler  *  has  suggested  the  formula 


F.  F. 


D  +  D'  +  C 


in  which  F.F.  is  called  the  Fusibility  Factor. 

N  =  sum  of  non-detrimentals,  or  silica,  alumina,  titanic  acid,  water, 
moisture  and  carbonic  acid. 

D  =  sum  of  detrimental  impurities,  or  iron,  lime,  magnesia,  alkalies, 
sulphuric  acid,  sulphur,  etc. 

D'=sum  of  alkalies  which  Wheeler  supposes  to  have  twice  the  flux- 
ing value. 

The  formula  without  C  was  not  much  more  regular  in  its  results 
than  Bischofs. 

1  Die  Feuerfesten  Thone,  p.  71, 1876.  *  Eng.  and  Min.  Jour.,  LVIL,  1894,  p.  224. 


38  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Wheeler  therefore  adds  the  term  C,  which  he  makes 

C  =  l  when  clay  is  coarse-grained  and  specific  gravity  exceeds.  .  . 


C  =  2     « 

CC          U              U                       U                    (C                  « 

"          from.  .  . 

....2  to  2.25 

C  =  3     " 

44          44              C£                       It                    U                  (« 

"         from  .  .  . 

..  .1.75  to  2.0 

C=2     « 

"     "  fine-grained         "          " 

"         above... 

r.  .2.25 

C  =  3     " 

<<            14            (C                     K                                   41                     (( 

"         from. .  . 

..  .2  to  2.25 

C  =  4     " 

((           44           44                   44                                44                   44 

"         from  .  .  . 

..  .1.75  to  2.0 

This  gives  better  but  still  not  regular  results.  The  insertion  of  a 
term  to  account  for  fineness  or  coarseness  is  perfectly  rational,  but  the 
specific  gravity  is  dependent  on  the  mineral  composition  of  the  clay 
and  therefore  indirectly  connected  with  chemical  constitution. 

MEASUREMENT    OF    TEMPERATURES. 

There  are  various  forms  of  pyrometers  for  determining  the  tempera- 
tures, depending,  according  to  their  principle,  on  the  fusion  of  alloys 
or  single  metals,  thermo-electricity,  fusion,  spectro-photometry,  expan- 
sion, etc.  Most  of  these  are  unreliable,  and  for  their  description  one 
is  referred  to  any  good  text-book.  Two  forms  of  pyrometer  deserve 
detailed  mention,  the  one  on  account  of  its  extreme  accuracy  and 
adaptability  in  many  places  where  a  little  care  is  used,  the  other  on 
account  of  its  very  fair  accuracy,  cheapness,  as  well  as  ready  applica- 
bility to  practical  use. 

THE  THERMO-ELECTRIC   PYROMETER. 

Le  Chatelier's  thermo-electric  pyrometer  depends  on  the  measure- 
ment of  a  current  generated  by  heating  a  thermo-pile.  The  latter  con- 
sists of  two  wires,  one  of  platinum  and  the  other  of  an  alloy  of  90# 
platinum  and  10fo  rhodium,  twisted  together  at  their  free  ends  for  a 
distance  of  about  an  inch,  and  the  next  foot  or  two  of  their  length 
enclosed  in  a  fire-clay  tube,  so  that  when  the  couple  is  inserted  into  the 
furnace  only  the  twisted  ends,  which  are  held  near  the  body  whose  tem- 
perature is  to  be  measured,  will  receive  the  full  heat.  The  two  wires 
connect  with  a  galvanometer,  the  deflection  of  whose  needle  increases 
with  the  temperature  at  the  point  where  the  free  end  of  the  wire  couple 
is  applied. 

For  use  the  instrument  has  to  be  first  calibrated,  but  this  can  be 
easily  done  with  a  little  care. 

As  at  present  put  on  the  market,  the  thermo-electric  pyrometer  costs 
about  $180,  and  this  high  price  has  always  tended  to  restrict  its  use. 
There  is  no  reason,  however,  why  one  should  not  be  made  for  about  $35. 

This  pyrometer  is  accurate  to  within  5  or  10  degrees  Fahr. 

SEGER'S   PYRAMIDS. 

These  consist  of  different  mixtures  of  kaolin  and  fluxes,  which  are 
compounded  so  that  there  shall  be  a  constant  difference  between  their 


PHYSICAL    PROPERTIES    OF    CLAY.  39 

fusing  points.  Seger's  series  were  numbered  from  1  to  20,  and  the  dif- 
ference between  their  fusing  points  is  36°  F.  A  later  series,  introduced 
by  Cramer,  runs  from  .01  to  .022  with  a  difference  of  54°  F.  between 
their  fusing  points.  The  higher  numbers  of  the  cones  have  also  been 
extended  up  to  36. 

These  pyramids  have  been  recently  recalibrated,  and  therefore  the 
fusing  points  and  composition  of  the  different  numbers  are  given  here- 
with, being  taken  from  the  recently  issued  circular  of  the  Thonin- 
dustrie  Laboratorium,  in  Berlin,  where  these  cones  were  first  made. 

FUSION  TEMPERATURES  BASED  UPON   RECENT  RECALCULATIONS  FOR  SEGER'S  PYRAMIDS. 


No.  of 
Cone. 

032 

021 
€20 
€19 
€18 
€17 
€16 
€15 
014 
€13 
012 
€11 
€10 

09 

€8 

07 

€6 

€5 

€4 

€3 


Composition. 

Fusion  Point 

0.5  Na.,0  ) 
0.5  PbO    \ 

(  2  Si02 
(  1  B.Oa 

Cent. 

590 

Fahr. 
1094 

0.5  Na.,0 
0.5  PbO    \ 

0.1Al2O3 

(  2.2  Si02 

(   1  BP:>, 

620 

1148 

0.5  Na.,0 
0.5  PbO    f 

0.2  A1,03 

(  2.4  Si02 
j  1  B20:j 

650 

1202 

0.5  Na90  ) 
0.5  PbO    f 

0.3  A1203 

(  2.6  Si02 
I  1  B203 

680 

1256 

0. 5  Na.,0  ) 
0.5  PbO    \ 

0.4  A1203 

(2.8Si02 

I    1  B  A 

710 

1310 

0.5  Na.,0  } 
0.5  PbO    \ 

0.5  A1203 

f  3.0  Si02 

1 1  B,o3 

740 

1364 

0.5  Na.,0  ) 
0.5  PbO    f 

0.55  A1203 

J  3. 1  Si02 
I  1  B203  - 

770 

1418 

0.5  Na.,0 
0.5  PbO    f 

0. 6  A1203 

|3.2Si02 
1 1  B  A 

800 

1472 

0.5  Na.,0 
0.5  PbO    j" 

0.65  A1.,03 

\  3.3  Si02 
I  1  B203 

830 

1526 

0.5  Na.,0  V 
0.5  PbO   / 

0.7Al2O3 

J"  3.4  Si02 
1 1  B203 

860 

1580 

0.5  Na.,0  } 
0.5  PbO    j" 

0. 75  A1203 

\  3. 5  Si02 
1  1  B203  ' 

890 

1634 

0. 5  Na,0  ) 
0.5  PbO    f 

0.8  A1203 

f  3.6  Si02 
I  1  B203 

920 

1688 

0.3  K.,0    ) 
0.7  CaO    \ 

0.2  Fe.,03 
0.3  A12"03 

j  3.50  Si02 
I  0. 50  B203 

950 

1742 

0.3  K.,0 
0. 7  CaO    \ 

0.2  Fe203 
0.3  A1203 

j  3.55  SiO., 
\0.45  B203 

970 

1778 

0.3  K.20    ) 

0. 7  CaO    \ 

0. 2  Fe203 
0.3  A1203 

{  3.60  Si02 
"(0.40  B,03 

990 

1S14 

0.3  K20    ) 

0. 7  CaO    J" 

0.2  Fe.,03 
0.2  A1203 

{  3. 65  SiO., 
}  0.35  B.,03 

1010 

is;,  0 

0.3  K20    ! 

0.7  CaO    f 

0.2  Fe203 
0.3  A1203 

J  3. 70  SiO, 
\0.30  B203 

1030 

L886 

0.3  K.,0    \ 

0. 7  CaO    j 

0.2  Fe.,0., 
0.3  A1203 

f  3. 75  SiO, 
\0.25B2O; 

1050 

L922 

0. 3  K.,0    ) 
0. 7  CaO    J" 

0.2  Fe203 
0.3  A1203 

(  3.80  Si02 
"j  0.20  B,03 

1070 

L958 

0.3  K.,0    ) 

0.7  CaO    / 

0.2  Fe2Os 
0.3  A1203 

(  3.85  Si02 
"/  0.1:,  B903 

1090 

1994 

40 


CLAY    DEPOSITS    IN    NORTH    CAROLINA. 


FUSION    TEMPERATURES,    ETC.— Continued. 
Composition. 


Fusion  Point. 


No.  of 
Cone. 

02 
01 

1 

2 

3 

4 

5 

6 

7 

8 

9 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 


0.3  K20 

0.7  CaO 

j 
J 

0.2Fe2OQ        j 
0.3  A1203J        ( 

3.90  Si02 
0.10  B203 

Cent. 

1110 

Fahr. 
2030 

0.3  K.,0 
0.7  CaO 

0.2  Fe203        \ 
0.3  A1203         ( 

3.95  Si02 
0.05  B203 

1130 

2066 

0. 3  K20 

0. 7  CaO 

1 

0.2Fe2O3        f 
0.3  A1203        \ 

4  Si02 

1150 

2102 

0.3  K20 
0.7  CaO 

0.2  Fe203        f 
0.4  A1203         ( 

4  Si02 

1170 

2138 

0.3  K20 
0.7  CaO 

0.05Fe2O3        j 
0.45  A1203         ( 

4  Si02 

1190 

2174 

0.3  K20 

0.7  CaO 

0.5  Al2034Si02 

1210 

2210 

0.3  K20 

0.7  CaO 

0.5  Al2Os5Si02 

1230 

2246 

0.3  K,0 
0.7  CaO 

0.6  Al2036Si02 

1250 

2282 

0.3  K20 

0.7  CaO 

0.7  Al2037Si02 

1270 

2318 

0.3  K20 
0.7  CaO 

0.8  Al2038Si02 

1290 

2354 

0.3  K00 
0.7  CaO 

0.9  Al2039Si02 

1310 

2390 

0.3  K20 
0.7  CaO 

1.0  Al2O310SiO2 

1330 

2426 

0.3  K20 
0.7  CaO 

I 

1.2  Al20312Si02 

1350 

2462 

0.3  K20 
0.7  CaO 

1.4  Al20314Si0.2 

1370 

2498 

0.3  K20 
0.7  CaO 

1.6  Al20316Si02 

1390 

2534 

0.3  K20 

0.7  CaO 

1.8  Al20318Si02 

1410 

2570 

0.3  K20 

0.7  CaO 

2.1  Al20321Si02 

1430 

2606 

0.3  K20 
0.7  CaO 

2.4  Al20324Si02 

1450 

2642 

0.3  K20 
0.7  CaO 

2.7  Al20327Si02 

1470 

26  7S 

0.3  K20 

0.7  CaO 

3.1  Al20331Si02 

1490 

2714 

0.3  K20 

0.7  CaO 

j 

3.5  Al20335Si02 

1510 

2750 

0.3  K20 

0.7  CaO 

3.9  Al20339Si02 

1530 

2786 

0.3  K20 
0.7  CaO 

4.4  Al20344Si02 

1550 

2822 

0. 3  K20 

0.7  CaO 

\ 

4.9  Al20349Si02 

1570 

2858 

0.3  K20 
0. 7  CaO 

5.4  Al20354Si02 

1590 

2894 

0.3  K20 
0.7  CaO 

6.0  Al2O360SiO2 

1610 

2930 

0.3  K20 

0.7  CaO 

6.6  Al20366Si02 

1630 

2966 

PHYSICAL    PROPERTIES    OF    CLAY.  41 

FUSION   TEMPERATURES,    ETC.- Continued. 

Composition. 


No.  of  i k 

Cone. 

™  0.7  CaO    j"     '*     ai2u3^smu2 

27  K20     h    on   Aifl  200S1O 
-7  Q  ?  CaQ     j.     ,..U  AI2U3-UU&lU5 

28  Al2O310SiO2 

29  Al2038Si02 

30  Al2036Si02 

31  Al2035SiOo 

32  Al2034Si02 

33  Al2033Si02 

34  Al2032.5Si02 

35  Al2032Si02 

36  AL,(X2Si09 


Fu 

sion  Point. 

Cent. 

Fahr. 

1050 

3002 

1070 

3038 

1000 

3074 

1710 

3110 

1730 

3146 

1750 

3182 

1770 

3218 

1790 

3254 

1810 

3290 

1830 

3320 

1850 

3862 

"When  these  pyramids  are  placed  in  a  kiln  or  furnace  they  begin 
to  soften  as  the  temperature  is  raised,  and  as  it  approaches  their  fusion 
point  the  cones  bend  over  until  the  tip  is  as  low  as  the  base.  "When 
this  occurs  the  temperature  at  which  they  fuse  is  considered  to  be 
reached. 

If  it  is  therefore  stated  that  a  clay  vitrifies  at  cone  5,  it  means  that  the 
amount  of  heat  required  to  make  cone  5  bend  over  is  sufficient  to  vitrify 
the  clay.  In  this  report  it  has  not  been  thought  advisable  to  use  this 
method  but  to  give  the  actual  temperatures.  Comparisons  can  be  easily 
made  by  looking  up  the  number  of  the  cone  in  the  foregoing  table. 

These  cones  are  accurate  to  within  25°,  which  is  entirely  sufficient 
for  practical  purposes.  In  actual  use  the  cones  are  set  in  the  kiln  at 
a  point  where  they  can  be  watched  through  a  peep-hole  but  will  not 
receive  the  direct  touch  of  the  flames  from  the  fuel. 

It  is  well  to  put  two  or  more  cones  in  so  that  warning  can  be  had  of 
the  approach  of  the  desired  temperature. 

In  order  to  determine  the  temperature  of  a  kiln,  several  cones  of 
separated  numbers  are  put  in,  as,  for  example,  .07,  1,  and  5.  Suppose 
that  .07  and  1  are  bent  over  in  burning,  but  5  remains  unaltered. 
The  temperature  of  the  kiln  was  therefore  between  1  and  5.  The 
next  time  2,  3  and  4  are  put  in.  2  and  3  may  be  fused,  but  4  remains 
unaffected.  The  temperature  therefore  reached  the  fusing  point  of  3, 
or  2174°  F.  If  the  cones  up  to  about  No.  2  are  heated  too  quickly, 
they  are  apt  to  swell  up,  and  prevent  themselves  bending  over. 

Seger's  cones  are  extensively  used  in  Europe,  and  in  America  their 
application  is  extending.  Their  one  great  advantage  is  that  they  indicate 
not  the  actual  temperature,  but  rather  its  action.  Thus  cone  No.  1  does 
not  bend  over  as  soon  as  the  temperature  of  2102°  F.  is  reached,  but  only 
when  this  temperature  has  penetrated  the  cone.     It  is  not  advisable  to 


42  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

use  a  cone  a  second  time,  in  case  it  lias  not  bent  over  in  a  previous  burn- 
ing.    Such  cones  are  apt  to  bend  at  a  lower  temperature. 

In  porcelain  manufacture,  cones  of  the  same  composition  as  the  glaze 
on  the  ware  are  sometimes  used. 

These  cones  can  be  obtained  for  about  one  cent  each  from  Prof.  E. 
Orton,  Jr.,  Ohio  State  University,  Columbus,  O. 

SLAKING   OF    CLAYS. 

"When  a  lump  of  clay  is  placed  in  water  it  begins  to  slake  or  break 
up  in  a  more  or  less  characteristic  manner,  depending  on  the  nature  of 
the  clay.  Some  homogeneous  clays  split  into  a  number  of  angular 
fragments,  others  into  scaly  particles,  while  still  others  break  up  com- 
pletely into  their  component  grains.  The  rapidity  of  slaking  varies, 
depending  largely  on  the  density  and  toughness  of  the  clays.  Some 
clays  slake  completely  to  pieces  in  two  or  three  minutes,  while  others 
may  lie  in  water  for  an  hour  or  two  and  remain  totally  unaffected. 

This  property  is  of  practical  importance  in  two  ways.  In  washing 
kaolins  or  stoneware  clays  it  is  desirable  that  they  should  fall  apart 
quickly  when  thrown  into  water,  and  thereby  permit  a  quicker  and 
more  thorough  separation  of  the  impurities. 

Slaking  is  also  of  importance  in  tempering  clays,  for  the  easier  they 
break  up  the  easier  and  more  thoroughly  will  they  become  mixed  in  the 
pugmill. 

MINOR   PHYSICAL   PROPERTIES    OF   CLAYS. 

The  other  physical  properties  of  clay,  such  as  absorption,  fineness  of 
grain,  taste,  color,  have  been  mentioned  in  connection  with  other  prop- 
erties and  need  be  but  briefly  referred  to  here. 

ABSORPTION    OF    WATER. 

The  absorption  of  clays  varies  of  course,  some  taking  up  a  large 
amount  of  water,  which  they  give  off  again  in  drying,  with  the  risk  of 
cracking  the  clay  unless  dried  very  slowly.  The  presence  of  organic 
matter,  ferric  hydrate  and  ammonia  may  increase  the  absorptive  power. 
The  residual  clays  common  throughout  the  western  half  of  the  State 
often  absorb  a  large  amount  of  water,  without  showing  much  plasticity. 
They  are  coarse-grained  and  very  porous,  and  show  the  property  not 
uncommon  to  many  clays,  in  that  they  become  more  plastic  as  water  is 
added  up  to  a  certain  limit,  but  a  slight  addition  over  this  causes  the 
clay  to  become  soft  and  decrease  rapidly  in  plasticity. 

TEXTURE  OF  CLAYS. 

Fineness  of  grain,  as  already  mentioned,  has  an  important  bearing  on 
the  fusibility  of  clays.     It  also  diminishes  the  tensile   strength,   and, 


PHYSICAL    PROPERTIES    OF    CLAY.  43 

with  few  exceptions,  requires  the  clay  to  be  slowly  dried,  and  in  burn- 
ing to  be  slowly  heated  at  first.  In  porcelain  manufacture  the  particles 
of  clay  must  be  of  extreme  fineness,  and  this  has  often  to  be  brought 
about  by  grinding. 

TASTE    OF    CLAYS. 

Tasting  a  clay  will  often  give  a  clue  to  the  presence  of  soluble  salts, 
such  as  sulphates  of  iron  or  magnesia,  which  may  impart  a  bitter,  inky 
taste  to  the  clay.  The  presence  of  grit  may  also  be  detected  by  grind- 
ing a  lump  of  the  clay  between  the  teeth. 

COLOR    OF    CLAYS. 

The  color  of  a  clay  serves  only  as  an  indication  of  its  quality  within 
very  wide  limits. 

Many  high-grade  clays  which  burn  white  are  in  their  original  or  green 
state  colored  black  by  the  presence  of  a  small  per  cent  of  organic  matter. 
The  latter,  however,  may  mask  the  presence  of  iron,  as  in  those  from 
Prospect  Hall,  which  burn  to  a  deep  red. 

Iron  may  color  a  clay  green,  yellow,  red,  gray,  brown  or  black, 
depending  on  the  condition  of  its  compound,  whether  ferrous  or  ferric. 
In  surface  clays  it  frequently  exists  in  the  ferric  condition  as  limonite 
or  hematite,  and  imparts  a  brilliant  yellow  or  red  to  the  clay.  E"ot 
unfrequently  the  upper  part  of  a  clay  bank  is  yellow  or  red,  due  to  the 
presence  of  abundant  ferric  oxide,  while  the  lower  portion  of  it  may 
be  blue  or  gray  from  the  iron  being  less  oxidized.  Many  kaolins  with  a 
very  small  percentage  of  ferric  oxide  burn  white  in  oxidizing  fire,  but  in 
reducing  fire  burn  gray,  due  to  a  reduction  of  the  iron  from  the  ferric 
to  the  ferrous  condition. 

The  colors  imparted  by  the  different  constituents  have  been  mentioned 
under  the  chemical  properties.  It  should  be  remembered  that  in  case 
the  clay  does  not  burn  to  a  color  which  the  analysis  would  indicate,  that 
it  may  be  due  to  the  union  of  the  elements  in  the  clay  with  substances 
in  the  fire  gases  of  the  kiln.  Many  coals  contain  sulphur.  In  burning 
the  sulphuric  acid  gases  are  apt  to  unite  with  the  lime  or  other  sub- 
stances in  the  clay,  with  formation  of  sulphates. 

DENSITY    OF    CLAYS. 

The  specific  gravity  of  a  clay  varies  with  its  mineralogical  composi- 
tion, and  may  run  from  about  1.75  to  2.60.  Thus  far  it  is  not  known  of 
itself  to  have  any  practical  value.  In  the  summary  of  tests  at  the  end 
of  the  report  will  be  found  the  specific  gravities  of  the  North  Carolina 
clays  here  described,  determined  by  Prof.  F.  P.  Tenable. 


CHAPTER  IV. 

GEOLOGY  AKD  GEOGEAPHY  OF  NORTH  CAROLINA 
CLAY  DEPOSITS. 

The  clay  deposits  of  North  Carolina  belong  to  two  types,  residual 
and  sedimentary,  which,  with  their  varieties,  may  be  grouped  as  follows : 

Kesidual : — Kaolins;   tire-clays;   and  impure  clays. 

('Coastal  plain  clays,  of  Cretaceous  or  Tertiary  age. 
a   j.         .  !  Sedimentary  surface  clays  (for  brick  and  pottery),  mainly  along 

y    j       the  streams  and  low-lands,  in  the  Piedmont  plateau  and  moun- 
[_      tain  counties. 

The  accompanying  outline  map  (Plate  II)  indicates  the  general  dis- 
tribution of  the  geological  formations  in  the  State,  except  that  no- 
attempt  is  made  to  separate  those  of  the  coastal  plain  region. 

RESIDUAL    CLAYS. 

These  in  general  are  to  be  found  in  any  portion  of  the  western  half 
of  the  State,  that  being  the  area  underlain  by  the  granitic,  gneissic,  and 
schistose  rocks  from  which  they  have  originated  by  the  decay  in  situr 
as  explained  under  the  origin  of  clay. 

The  eastern  border  of  this  area  of  crystalline  rocks  passes  through  the 
counties  of  Halifax,  Eranklin,  Wake,  Chatham,  Moore,  Kichmond,  and 
Anson. 

West  of  this  line,  which  passes  near  Weldon,  Raleigh  and  Rocking- 
ham, we  find  the  residual  clays  forming  an  almost  universal  mantle  over 
the  surface.  They  are  generally  coarse-grained,  red,  brown  or  yellow 
sticky  clays,  frequently  of  a  lean  character.  Their  thickness  varies  from 
three  to  twenty  or  more  feet,  depending  on  the  depth  to  which  disinteg- 
ration of  the  rock  has  taken  place  and  the  amount  of  erosion  of  the  sur- 
face that  has  occurred.  In  general,  we  may  expect  to  find  them  of  less 
thickness  on  the  steep  slopes  than  on  the  gentler  ones  or  level  areas. 

It  not  unfrequently  happens  that  the  clay  has  been  little  disturbed, 
and  the  banded  structure  of  the  gneiss  or  schist  from  which  it  originated 
may  still  be  seen  extending  upward  into  the  clay.  As  quartz  decom- 
poses more  slowly  than  most  rock-forming  minerals,  the  veins  of  this 
material  are  also  to  be  seen  at  times  traversing  the  clay. 

Residual  clays  commonly  contain  many  angular  grains  and  frag- 
ments of  undecomposed  or  only  partially  decomposed  mineral  matter, 
and  the  relative  amount  of  this  depends  on  the  extent  of  the  rotting  of 
the  rock. 


GEOLOGY  AND  GEOGRAPHY  OF  NORTH  CAROLINA  CLAY  DEPOSITS.    45 

The  brickmakers  are  very  prone  to  use  these  materials  on  account  of 
their  sandy  nature,  their  lean  character  making  them  much  easier  to  work 
by  hand;  at  the  same  time  their  porous  nature  produces  a  porous,  weak 
brick  unless  properly  burned,  and  at  the  smaller  brickyards  the  burning 
is  seldom  carried  far  enough. 

The  composition  of  two  of  these  impure  residual  clays  is  given  below : 


Composition  of  Residual  Clays. 

Dean's  Yard,       Greensboro 
Greensboro.      Brk.  &  Tile  Co. 

Moisture    1.90  1.64 

Silica 59.27  56.81 

Alumina   22.31  20.62 

Ferric  oxide 6.69  6.13 

Lime    25  .65 

Magnesia 13  .58 

Alkalies    90  4.47 

Water  (loss  on  ignition)   9.00  8.60 

Total   100.45  99.50 

Free  sand  33.35  40.65 

Fluxes 7.97  11.S3 

The  residual  fire-clays  found  at  Pomona  and  Grover  are  coarse- 
grained, sandy  clays  of  a  semi-refractory  nature,  with  much  intermixed 
quartz  and  mica.  At  times  these  two  mineral  impurities  may  become 
so  abundant  that  the  portions  of  the  vein  holding  them  have  to  be 
avoided  in  mining. 

As  these  semi-refractory  clay  deposits  have  been  but  little  worked 
thus  far,  not  very  much  can  be  said  of  their  extent.  Vein  formations 
such  as  they  result  from  are  often  apt  to  be  of  a  pocket-like  nature,  but 
at  times  are  very  extensive,  so  that  they  should  be  well  exploited  before 
much  mining  is  done. 

These  residual  clays  are  sometimes  found  such  a  short  distance  from 
their  point  of  origin  that  they  still  practically  possess  their  residual 
characteristics  of  leanness,  coarseness,  angularity  of  fragments,  etc. 

The  kaolins,  which  also  come  under  this  head,  are  of  the  greatest 
commercial  value.  They  result  from  the  decomposition  of  feldspar  or 
granite  veins,  so  abundant  in  the  crystalline  area  of  ISTorth  Carolina. 
In  width  they  vary  from  a  few  inches  to  300  feet,  and  the  kaolin 
extends  from  the  surface  to  a  depth  of  60  to  120  feet,  depending  on  the 
extent  to  which  the  feldspar  has  altered.  Below  this  the  fresh  or  par- 
tially altered  rock  is  met.  In  their  unaltered  state  these  vein.-  may 
serve  as  sources  of  feldspar  or  quartz,  which,  when  of  sufficient  purity, 
are  available  for  potters'  use. 

The  kaolin  deposits  at  TTebster,  N.  C,  have  been  worked  for  a  num- 


16  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

ber  of  years  to  supply  the  potteries  at  Trenton,  X.  J.,  and  East  Liver- 
pool, Ohio.  The  field  work  and  laboratory  tests  carried  on  in  con- 
nection with  the  preparation  of  this  report  indicate  additional  ones  of  a 
very  promising  nature. 

SEDIMENTARY   CLAYS. 

The  coastal  plain  deposits  of  North  Carolina  furnish  the  most  exten- 
sive beds  of  clay  to  be  found  within  the  State.  They  have  been  classed 
as  belonging  to  the  Potomac  (lower  Cretaceous),  Tertiary,  and  post- 
Tertiary  (Columbia)  formations.1 

The  former  are  best  exposed  along  the  Cape  Tear  river  below  Eay- 
etteville, and  consist  of  dark-colored  clays,  at  times  very  sandy  and 
frequently  containing  an  abundance  of  organic  matter. 

The  clay  usually  forms  large  lenses,  and  sometimes,  by  the  increase 
of  sand,  passes  into  sand  beds.  One  of  the  best  exposures  of  these 
black  Potomac  clays  is  at  Prospect  Hall,  21  miles  below  Eayetteville; 
but  they  are  exposed  also  in  many  of  the  river  bluffs  from  10  to  60 
miles  below  Eayetteville  (p.  102). 

The  Eocene  deposits  are  best  exposed  along  the  western  border  of  the 
coastal  plain  region  in  Moore  and  Harnett  counties,  lying  near  or  at 
the  summits  of  the  sand  hills  and  ridges.  Their  thickness  varies  from 
5  to  15  feet,  or  possibly  more,  and  there  usually  is  but  little  (2  to  6  feet) 
of  sandy  overburden.  The  best  known  exposures  of  these  are  on  the 
Sprunt  lands,  2  to  3  miles  north  of  Spout  Springs,  and  2  miles  southeast 
of  Southern  Pines  on  the  Seaboard  Air  Line  Railway. 

There  are  good  exposures  of  clay  in  the  cuts  of  the  Cape  Eear  and 
Yadkin  Valley  P.  R.  between  Spout  Springs  and  Eayetteville,  the  age 
of  which  is  not  certain,  though  they  are  probably  Eocene  or  Cretaceous. 

The  composition  of  these  latter  clays  (see  table  at  the  end  of  report) 
might  lead  one  to  assign  a  refractory  character  to  them,  but  their 
extreme  fineness  of  grain  causes  them  to  fuse  at  comparatively  low  tem- 
peratures. Their  smoothness  is  marked,  and  they  might  be  used  for 
other  purposes. 

Finely  laminated  clays  of  various  colors  are  also  to  be  found  exposed 
in  railway  cuts  and  river  bluffs  in  many  parts  of  the  coastal  plain 
region,  in  some  places  associated  with  tertiary  marls,  and  elsewhere 
overlying  them.  Along  the  western  border  of  the  coastal  plain  region, 
both  in  the  river  bluffs  and  on  the  divides  between  the  streams,  as  are 
to  be  seen  at  intervals  along  the  Atlantic  Coast  Line  R.  R.  from 
Weldon  to  a  few  miles  south  of  Eayetteville,  are  beds  of  finely  laminated 
clays  varying  in  color  from  yellowish  to  nearly  black,  and  often  mot- 
tled, which  are  believed  to  be  a  part  of  the  Lafayette  formation.     None 

1  J.  A.  Holmes.    "  The  Kaolin  and  Clay  Deposits  of  North  Carolina,"  Trails.  Amer.  Inst.  Min. 
Eng.  XXV,  p.  929, 1896. 


GEOLOGY  AND  GEOGRAPHY  OF  NORTH  CAROLINA  CLAY  DEPOSITS.    47 

of  these  clays  has  yet  been  fully  tested,  but  the  results  of  their  exam- 
ination will  be  described  in  a  later  report. 

There  is  also  to  be  found  in  the  terraces  bordering  the  larger  streams 
for  some  miles  above  and  below  where  they  pass  from  the  hill  country 
into  the  coastal  plain  region,  a  series  of  red  and  brown  loams,  which, 
near  Weldon,  Goldsboro  and  Fayetteville,  in  North  Carolina,  and  at'  as 
many  points  similarly  located  in  other  Southern  States,  have  been  found 
to  make  good  brick  when  properly  manipulated.  These  "  brick  loams," 
as  they  have  been  designated,  are  of  still  more  recent  origin  than  the 
laminated  Lafayette  clays  mentioned  above,  and  they  are  classed  with 
the  youngest  of  our  extensive  geological  formations,  that  known  as  the 
Columbia. 

Many  of  the  rivers  farther  inland,  as  they  pass  across  the  hill  country, 
and  even  in  the  mountain  region,  are  often  bordered  by  considerable 
stretches  of  terrace  which  are  underlain  by  brick  or  pottery  clays,  often 
of  excellent  quality. 

,  The  more  sandy  clays  under  these  terraces  are  generally  to  be  found 
close  to  the  river,  while  the  finer  grained  and  smoother  ones  have  been 
deposited  nearer  shore  at  the  edge  of  the  terrace,  and  when  there  are 
several  terraces  they  are  usually  found  under  the  upper  one. 

Such  terraces  are  abundant  along  the  Catawba  river  near  Morgan- 
ton  and  Mount  Holly;  along  the  Yadkin  river,  especially  at  Wilkes- 
boro  and  Elkin;  along  the  Clarke  river  (south  fork  of  Catawba  river) 
at  Lincolnton,  where  clay  to  supply  some  fifty  potters  is  dug. 

It  is  from  these  terrace  deposits  of  recent  geologic  age  that  some  of 
the  best  clays  in  the  State  are  to  be  obtained.  In  depth  they  vary  from 
five  to  ten  feet,  and  as  some  of  these  river  valleys  supply  the  lines  of 
railroad  with  an  easy  passage  through  the  mountain  regions,  the  clays 
are  well  located  for  shipment  either  in  their  burned  or  unburned  con- 
dition. 

These  river  clays  are  also  well  developed  along  the  French  Broad 
river  near  Asheville;  and(  at  Biltmore  they  have  produced  excellent  and 
extremely  encouraging  results. 

It  not  uncommonly  happens  that  the  river  terrace  is  formed  on  the 
slope  of  some  hill  covered  by  coarse-grained,  lean,  residual  clays,  and 
by  the  gradual  creep  of  the  soil  the  residual  material  moves  down  on  to 
the  sedimentary  clay  underlying  the  terrace.  Such  conditions  are  not 
uncommon,  and  at  first  sight  the  section  of  this  kind  exposed  in  a  clay 
bank  presents  a  rather  peculiar  appearance. 

As  mentioned  above,  the  sedimentary  clays  are  also  well  developed 
around  Wilson,  Goldsboro  and  Fayetteville. 

With  proper  treatment,  as  will  be  mentioned  later,  these  clays  are 
capable  of  excellent  results,  and  yet  by  careless  methods  the  product 
that  is  sometimes  produced  is  not  fit  to  use. 


48  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Just  as  much  care  should  be  taken  in  the  manufacture'  of  brick  as  in 
white  ware.  There  is,  unfortunately,  too  much  disposition  to  regard 
a  brick  as  so  many  cubic  inches  of  burned  clay  that  must  be  able  to 
stick  together  and  little  more. 

The  omnipresence  of  residual  brick  clays  in  the  South  has  had  an 
injurious  effect  on  the  clay-working  industry,  for  when  a  large  cotton 
mill  or  other  building  is  erected  the  contractor  generally  digs  up  the 
nearest  residual  clay  soil,  the  most  siliceous  he  can  find,  and  even  then 
sand  is  sometimes  added  to  it  to  permit  its  mixing  with  the  minimum 
amount  of  labor. 

This  clayey  sand  is  then  molded  by  hand  and  hurriedly  burned  in 
small  scove  kilns.  The  great  amount  of  sand  naturally  tends  to  make 
a  porous  brick,  and  burning  the  kiln  barely  to  incipient  fusion,  and 
never  much  beyond,  prevents  the  clay  from  reaching  its  maximum 
shrinkage.     The  result  is  a  porous,  soft  brick. 

The  sedimentary  clays  generally  make  a  smoother,  denser  brick,  and 
one  which  burns  at  a  lower  temperature,  but  the  residual  brick  clays  are 
frequently  capable  of  good  results  if  properly  handled. 

Clays  for  making  good  common  and  pressed  brick  are  of  as  much 
importance  in  North  Carolina  as  stoneware  clays  and  kaolins,  for  prac- 
tically all  the  pressed  brick  now  used  in  the  State  are  shipped  from  other 
States. 

THE    NORTH    CAROLINA   CLAY-WORKING   INDUSTRY. 

The  products  at  present  manufactured  in  North  Carolina  include 
stoneware,  earthenware,  fire-brick,  sewer-pipe,  flue-linings,  drain-tile 
and  building  brick. 

Stoneware  is  manufactured  by  a  number  of  small  potters  located 
chiefly  in  the  western  part  of  the  State.  The  clays  used  burn  to  a  dense 
hard  body  at  moderate  temperature,  2100°  F.,  but  the  ware  has  a  rough 
surface  aue  to  the  glazing  material,  which  contains  much  grit.  The 
same  potters  make  red  earthenware  articles  to  a  limited  extent.  "With 
the  available  clays  there  is  room  for  much  improvement  in  the  character 
of  the  ware. 

Fire-brick  are  manufactured  at  Pomona,  Guilford  county,  Emma, 
Buncombe  county,  and  Grover,  Cleveland  county.  In  each  case  the 
clays  are  coarse-grained,  sandy  ones,  with  much  quartz  and  mica. 
Those  at  Grover  especially  would  probably  make  a  very  good  grade  of 
refractory  material,  but  their  application  has  thus  far  been  limited. 

Sewer-pipe  and  flue-linings  are  only  made  at  Pomona,  Guilford 
county,  but  the  factory  located  at  that  place  is  turning  out  a  very  good 
product,  and  it  has  recently  been  much  enlarged. 

Common  brick  are  manufactured  at  many  localities  throughout  the 


GEOLOGY    AND    GEOGRAPHY    OF    NORTH    CAROLINA    CLAY    DEPOSITS.       49 

State,  but  pressed  brick  have  not  passed  beyond  the  experimental  stage; 
although  many  of  the  clays  are  admirably  adapted  for  this  purpose,  as 
those  near  Asheville,  Buncombe  county,  at  Wilkesboro,  Wilkes  county, 
around  Goldsboro,  Wayne  county,  and  Raleigh,  Wake  county. 

Many  of  these  towns  are  at  the  intersection  of  several  lines  of  railroad, 
so  that  the  product  could  be  easily  shipped. 

In  visiting  the  various  localities  for  the  collection  of  samples  for 
analysis  and  physical  tests,  this  point  has  been  borne  in  mind,  and  the 
areas  most  accessible  have  been  especially  examined. 


CHAPTER  V. 
KAOLINS  OR  CHINA  CLAYS. 

CHARACTER,    MINING,    PREPARATION   POR   MARKET. 

North.  Carolina  is  one  of  the  important  producers  of  kaolin  used  by 
the  manufacturers  of  white  granite,  C.  C.  (cream-colored)  ware,  and 
porcelain,  at  Trenton,  East  Liverpool  and  other  localities  in  the  United 
States,  and  the  material  produced  stands  second  to  none  thus  far  mined 
in  this  country. 

All  of  the  North  Carolina  kaolins  thus  far  discovered  are  of  a  resid- 
ual nature,  that  is,  the  material  is  found  at  the  point  where  it  originated. 
They  have  resulted  from  the  decay  of  veins  of  pure  feldspar,  pegmatite 
or  granite,  and  vary  in  their  initial  impurity  according  to  the  number  of 
foreign  minerals  which  occurred  in  the  vein  from  which  they  were 
formed. 

DISTRIBUTION    OF    THE    KAOLINS. 

Knowing  thus  the  nature  of  their  origin,  it  is  possible  to  predict 
approximately  the  limits  within  which  they  can  occur.  As  the  feld- 
spar and  granite  veins  are  generally  found  cutting  the  gneisses, 
granites  or  hornblende  and  mica  schists,  the  kaolin  deposits  can  occur 
in  any  part  of  the  central  or  western  parts  of  the  State,  this  being  the 
area  underlain  by  the  crystalline  rocks.  Large  deposits  have  thus  far 
been  recorded  from  Montgomery,  Richmond,  Cleveland,  Burke,  Jack- 
son, and  Macon  counties. 

MINEKALOGICAL    CHARACTER    OF    KAOLIN. 

The  kaolin  from  most  of  these  veins  is  a  white,  dense,  soapy  sub- 
stance, soft  and  easily  picked  out.  Through  this  may  be  scattered  scales 
of  mica,  garnet,  quartz,  etc.  The  mica  is  generally  fresh  in  appearance 
unless  it  is  an  iron-bearing  species.  The  garnet  is  almost  invariably 
decomposed  and  forms  rusty  stains  which  can  generally  be  eliminated 
in  washing.  The  quartz  is  practically  always  undecomposed  and  in 
angular  fragments.  Its  condition  determines  the  necessity  of  its  sepa- 
ration; that  is  to  say,  if  the  quartz  were-  extremely  fine  its  presence 
would  be  harmless.  If  the  vein  was  originally  a  coarsely  crystalline 
mass  of  quartz  and  feldspar,  the  former  remains  in  such  large  fragments 
that  it  is  necessary  to  eliminate  it  by  washing;  but  if  the  quartz  and 


KAOLINS    OK    CHINA    CLAYS.  51 

feldspar  were  intimately  associated  in  a  finely  granular  mixture,  then 
the  quartz  may  be  scattered  through  the  kaolin  in  the  form  of  a  fine 
siliceous  powder,  and  if  there  are  no  other  impurities  with  it,  the  quartz 
can  be  left  in  the  kaolin. 

Indeed,  it  sometimes  happens  that  there  is  so  much  finely  divided 
quartz  present  that  it  is  impossible  to  separate  all  of  it  by  washing. 
This  is  the  case  with  the  kaolin  from  Troy. 

Depending,  therefore,  on  the  character  of  the  quartz,  the  washed 
kaolin  from  different  localities  may  show  a  very  variable  amount  of 
clay  substances. 

In  the  case  of  the  Webster  kaolin  the  quartz  forms  a  large  mass  in 
the  centre  of  the  vein,  and  is  left  standing  while  the  kaolin  is  mined 
away  on  either  side. 

In  Plate  V,  facing  page  59,  fig.  2  shows  a  bed  of  residual  clay  near 
Grover,  and  fig.  1  an  extensive  vein  of  residual  kaolin  near  Webster. 

PKOPERTIES    OF    KAOLIN. 

Kaolin  of  good  quality  is  pure  white  when  washed  and  dried,  but 
often  gray  when  wet.  The  purest  North  Carolina  kaolin,  and  also  other 
American  kaolins,  show  on  microscopic  examination  bunched  and  also 
isolated  scales  of  kaolinite,  plates  and  scales  of  white  mica,  grains  of 
quartz,  and  apparently  feldspar  grains. 

The  plasticity  of  kaolin  is  usually  very  lean,  although  some  crude 
kaolins  are  appreciably  plastic  to  the  feel.  The  tensile  strength  is  always 
low,  and  in  the  North  Carolina  kaolins  varies  on  the  average  from  5  to 
20  lbs.  per  square  inch.  Most  kaolins  absorb  considerable  water  in 
being  worked  into  a  plastic  paste.  They  burn  to  a  white  body  when 
little  iron  is  present,  and  the  hardness  and  density  vary  with  the  degree 
of  temperature  to  which  they  are  subjected,  and  also  with  the  amount 
of  quartz  and  feldspar  which  they  contain.  In  the  manufacture  of  china 
the  kaolin  is  mixed  with  ball  clay  to  give  the  mass  plasticity,  and  feld- 
spar to  act  as  a  flux.  Quartz  is  also  added  to  prevent  excessive  shrink- 
age.    It  is  in  this  connection  that  the  value  of  a  rational  analysis  is  felt. 

The  rational  analysis  considers  a  clay  as  being  made  up  of  quartz, 
feldspar,  and  kaolinite  or  clay  substance,  and  shows  the  amount  of  each 
present  in  the  clay.  If  now  the  potter  changes  from  the  kaolin  lie  bas 
been  using  to  one  from  another  locality,  it  will  be  possible  for  him,  if  he 
has  a  rational  analysis  of  this  new  clay,  to  determine  without  endless 
experimenting  how  to  vary  the  amount  of  quartz  and  feldspar  whic 
adds  to  his  mixture  in  order  to  produce  one  which,  with  the  new  ka<  lin, 
will  give  as  good  results  as  the  old  one. 

The  method  of  rationally  analyzing  clays  is  discussed  under  the 
"Chemical  Analysis  of  Clay  "  (pp.  29-33),  but  a  few  points  regardii  g  it 


52  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

may  also  be  stated  here.  Clays  may  agree  in  their  ultimate  chemical 
composition,  but  disagree  widely  in  their  rational  composition.  Clays 
showing  the  same  rational  composition,  will,  other  things  being  equal, 
usually  have  the  same  shrinkage.  If  they  differ  in  the  degree  of  fine- 
ness of  their  particles,  they  may  show  a  different  shrinkage,  even  though 
they  analyze  alike  rationally.  In  porcelain  and  white  earthenware 
manufacture  the  clay  is  generally  ground  so  fine  that  this  last  point 
does  not  have  to  be  considered. 

A  rational  analysis  has  been  made  of  the  kaolins  of  Xorth  Carolina. 

The  fact  that  a  kaolin  does  not  contain  98$  of  clay  substance  need  not 
cause  the  slightest  uneasiness.  The  important  requirement  is  a  very  low 
percentage  of  iron.  If  in  addition  to  clay  substance  the  clay  contains 
quartz  and  feldspar,  then  just  so  much  less  quartz  and  feldspar  will  have 
to  be  added  in  making  up  the  porcelain  or  other  mixture.  The  cele- 
brated French  kaolins  which  do  not  have  to  be  washed  sometimes  con- 
tain 38^  feldspar.1 

An  examination  of  the  following  table  shows  that  there  is  consider- 
able variation  in  the  proportion  of  clay  substance,  quartz  and  feldspar 
present. 

Table  showing  variation  in  clay  substance,  quartz  and  feldspar. 
Percentage  of  clay  substance,  quartz,  and  feldspar  in  North  Carolina  kaolins. 

Clay 

Locality.  substance.  Quartz.  Feldspar. 

Sylva  (washed),  N.  Ca.  Min.  &  Mfg.  Co.  (57)  94.21  5.75 

Webster  (washed),  Harris  Clay  Co.  (53)...  .  96.81  0.07  3.12 

(unwashed),  G.  Springer  (54) 66.14  15.61  18.91 

(washed),  G.  Springer  (56) 93.24  ■  6.60 

Bostick  Mills  (unwashed)  (21) 49.30  41.50  9.20 

(22) 36.05  62.33 

«       (washed)  (20) 54.30  43.85  1.S2 

Troy,  darker  kaolin  (64a) 14.71  83.94  1.91 

(64)  (washed) 20.83  76.20  2.34 

"    white  kaolin  (68)         "        58.92  35.27  5.81 

Wests  Mill,  Macon  Co.,  crude  kaolin  (69)...  83.39  14.98  1.58 

It  will  be  seen  from  the  above  that  the  free  sand  or  insoluble  residue 
in  the  North  Carolina  kaolins  is  nearly  all  quartz. 

The  variations  in  the  total  percentages  of  the  washed  samples  is  as 

follows : 

Variation  in  composition  of  kaolin,  ivashed  samples. 

Silica 44.08  to  S6.03$ 

Alumina 6.46   «  41.70 

Ferric  oxide 2S   "     2. 97 

Lime 15   "       .50 

Magnesia 09   "       .20 

Alkalies 25   «     2.4S 

Water  (loss  on  ignition) m 2.90   "   13.56 

1  Seger's  Ges.  Schrift,  p.  552. 


KAOLINS    OR    CHINA    CLAYS.  53 

The  special  point  of  interest  in  these  analyses  is  the  iron  percentage. 
The  per  cent,  of  iron  in  the  various  washed  kaolins  and  their  color  on 
burning  are  as  follows : 

Table  showing  per  cent,  of  ferric  oxide  in  washed  kaolin,  and  color  on  burning. 

Ferric  oxide,  Color  of 

Locality.                                             percentage.  burned  clay. 

(         .28 

G.  Springer,  Webster "  &  1  08  F  O  White. 

Wests  Mill 1.18  White. 

Harris  Clay  Co.,  Webster 1.41  White. 

Sylva 1.86  White. 

(  White,  faint 

Bostick  Mills 2.14  \      ..      ' 

(  yellow  tinge. 

Dark  kaolin,  Troy 2.18  Light  buff. 

White  kaolin,  Troy 2.97  Red  buff. 

This  affords  an  interesting  series  from  which  to  determine  the  permis- 
sible limit  of  iron  in  a  kaolin.  It  would  seem  from  this  that  the  extreme 
safety  limit  is  2$,  but  still  under  1.5$  is  more  desirable.  It  should  be 
remembered  that  there  might  be  2  or  3$  of  ferric  oxide  without  its  pres- 
ence being  noticed,  provided  there  was  also  present  6  to  9$  of  lime  to 
bleach  it.  But  still  it  is  undesirable  to  have  to  count  on  this,  and  even 
if  this  condition  existed  the  kaolin  would  burn  yellowish  white  and  not 
pure  white. 

MINING    OF    KAOLIN. 

Kaolin  is  usually  soft  enough  to  be  mined  with  a  pick  and  shovel. 

If  the  kaolin  deposit  is  large  and  broad,  it  can  be  worked  as  an  open 
pit,  digging  out  the  material  with  picks  and  shovels  and  loading  it  into 
wheelbarrows  or  cars,  which  are  drawn  or  pushed  to  the  washing 
troughs,  or,  if  the  pit  is  deep,  brought  to  the  foot  of  an  incline  and  then 
hauled  up  by  means  of  a  cable. 

Most  of  the  North  Carolina  kaolin  deposits  are  vein  formations  whose 
depth  is  comparatively  great  as  related  to  their  width.  In  such  in- 
stances the  method  of  sinking  pits  is  adopted.  This  consists  in  sinking 
a  circular  pit  in  the  kaolin  about  25  feet  in  diameter.  As  the  pit  pro- 
ceeds in  depth  it  is  lined  with  a  cribwork  of  wood,  as  shown  in  fig.  2 
of  Plate  III,  which  will  be  found  facing  page  56.  This  lining  is  ex- 
tended to  the  full  depth  of  the  pit,  which  varies  from  50  to  100  or  even 
120  feet.  When  the  bottom  of  the  kaolin  has  been  reached  the  filling- 
in  of  the  pit  is  begun,  the  cribwork  being  removed  from  the  bottom  up- 
wards as  the  filling  proceeds.  If  there  is  any  overburden  it  is  generally 
a  good  plan  to  use  this  for  filling  in  the  pits. 

As  soon  as  one  pit  is  filled  a  new  one  may  be  sunk  in  the  same  manner 
right  next  to  it.     In  this  ,way  the  whole  vein  is  worked  out,  and,  if  the 


54  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

deposit  is  large,  several  pits  may  be  sunk  at  the  same  time  to  increase 
the  output  of  the  mine. 

The  kaolin  is  taken  from  the  pit  in  buckets,  which  are  operated  by  a 
derrick.     At  the  mouth  of  the  pit  it  is  discharged  into  barrows  or  cars. 

Two  other  methods  of  mining  may  be  mentioned. 

If  the  deposit  is  deep  and  narrow,  and  the  better  portions  of  the  kaolin 
are  irregularly  scattered  through  the  vein,  it  may  be  cheaper  to  sink 
a  shaft  and  run  levels  from  this  into  the  better  parts  of  the  bed.  These 
levels  generally  have  to  be  timbered  and  the  shaft  also  requires  lining. 

Hydraulic  mining  has  been  tried  with  success  in  some  very  sandy, 
loose-grained  kaolins,  but  is  not  used  in  Xorth  Carolina.  The  method 
as  sometimes  used  consists  in  washing  the  clay  down  into  the  bottom 
of  the  pit,  whence  it  is  sucked  up  by  means  of  a  pump  and  discharged 
from  the  conveying  pipe  into  the  washing  trough. 

It  is  sometimes  necessary  to  have  a  scraper  to  stir  or  loosen  up  the 
clay  in  order  to  permit  its  being  sucked  up  more  easily.  Where  appli- 
cable, this  is  a  cheap  and  rapid  method,  but  most  kaolins  are  too  dense 
and  not  sandy  enough  to  permit  its  being  used. 

At  the  Harris  Clay  Company's  mines,  near  "Webster,  the  mines  are 
at  a  higher  level  than  the  washing  plant,  and  the  kaolin,  after  being 
trammed  for  a  few  hundred  feet  from  the  mouth  of  the  pits,  is  dis- 
charged directly  into  a  trough  leading  down  the  slope  to  the  washing 
works.  A  current  of  water  is  pumped  up  the  slope  and  discharged  into 
the  trough  to  wash  the  kaolin  down. 

A  kaolin  bed  to  be  of  commercial  value  should  not  be  less  than  8  feet 
thick. 

The  workable  depth  depends  on  the  distance  below  the  surface  to 
which  the  feldspar  has  kaolinized. 

PREPARATION    OF    KAOLIN    FOR    MARKET. 

Most  kaolins  are  washed  before  shipment.  This  is  done  to  eliminate 
coarse  particles  and  substances  such  as  iron,  which  would  render  the 
clay  fusible  or  discolor  it  in  burning. 

Two  methods  of  washing  may  be  used.  The  first  consists  in  throw- 
ing the  kaolin  into  large  circular  tubs  or  "  blungers "  filled  with 
water;  in  these  tubs  there  revolve  arms  which  stir  the  mass  up  to  a 
mixture  of  creamy  consistency.  By  this  treatment  the  fine  kaolinite 
particles  and  some  very  fine  quartz,  feldspar  and  mica  grains  remain  in 
suspension  while  the  coarser  particles  drop  to  the  bottom.  The  water, 
with  the  kaolin  in  suspension,  is  then  drawn  off  to  the  settling  tanks. 

A  modification  of  this  consists  in  the  use  of  a  large  cylinder,  closed  at 
both  ends.  The  cylinder  is  set  in  a  horizontal  position  and  contains  an 
axis  with  iron  arms,  which  as  the  axis  revolves  serve  to  break  up  the 


KAOLINS    OK    CHINA    CLAYS.  0  0 

•clay.  The  latter  is  charged  through  a  hopper,  and  a  current  of  water 
passes  into  the  end  of  the  cylinder,  while  at  the  other  end  the  water 
passes  out  with  the  fine  clay  particles  in  suspension,  the  coarser  ones 
remaining  in  the  cylinder. 

The  amount  of  water  used  has  to  be  regulated  by  experiment.  If  an 
excess  is  used,  too  much  coarse  material  will  be  washed  out  of  the  cylin- 
der, and  conversely  if  the  current  is  too  slow,  the  clay  will  not  yield  a 
sufficient  percentage  of  washed  material.  The  coarse  sand  remains  in 
the  cylinder  and  has  to  be  removed  from  time  to  time,  depending  on  the 
capacity  of  the  cylinder  and  amount  of  coarse  sand  in  the  clay.  \Vhen 
the  water  and  suspended  clay  leave  the  machine  they  are  conducted  to 
the  settling  tanks. 

This  method  is  little  used  in  this  country  for  the  purification  of  the 
crude  material,  although  it  is  extensively  used  abroad. 

The  prevalent  method  of  washing  kaolin  in  the  United  States  is  by 
means  of  troughs,  and  the  details  of  this  method  are  as  follows: 

As  the  kaolin  comes  from  the  mine  it  is  generally  discharged  into  a 
log-washer.  This  consists  of  a  semi-cylindrical  trough,  in  which  there 
revolves  a  horizontal  axis  bearing  short  arms.  The  action  of  these  arms 
breaks  up  the  kaolin  more  or  less  thoroughly,  depending  on  its  density, 
.and  facilitates  the  subsequent  washing.  The  stream  of  water  directed 
into  the  log-washer  sweeps  the  kaolin  and  most  of  the  sand  into  the 
washing  troughs,  which  latter  are  about  15  inches  wide  and  12  inches 
•deep.  They  may  be  wider  and  deeper  if  the  kaolin  is  very  sandy; 
in  fact,  they  should  be.  The  troughing  is  about  700  feet  long,  and  to 
utilize  the  space  thoroughly  it  is  broken  up  into  sections  (50  feet  each 
is  a  good  length),  these  being  arranged  parallel,  and  connecting  at  the 
ends,  so  that  the  water,  with  suspended  clay,  follows  a  zig-zag  course. 
This  trough  has  a  slight  pitch  in  the  North  Carolina  plants,  being  about 
one  inch  in  20  feet,  but  this  is  a  matter  depending  on  the  kaolin.  If 
the  kaolin  is  very  fine  and  settles  slowly,  the  pitch  need  not  be  so  great, 
.and  vice  versa.  A  large  quantity  of  very  coarse  sand  in  the  kaolin  is 
a  nuisance,  as  it  clogs  up  the  log-washer  and  upper  end  of  the  trough 
more  quickly,  and  causes  so  much  more  labor  to  keep  them  clear.  As 
it  is,  considerable  sand  settles  there,  and,  to  keep  the  trough  clear,  sand 
wheels  are  used.  These  are  wooden  wheels  bearing  a  number  of  iron 
scoops  on  their  periphery.  As  the  wheel  revolves  these  scoops  catch  up 
a  portion  of  the  sand  which  has  settled  in  the  trough,  and  as  each  scoop 
reaches  the  upper  limit  of  its  turn  on  the  wheel,  it,  by  its  inverted  posi- 
tion, drops  the  sand  outside  of  the  trough.  These  sand  wheels  are  a 
help,  but  it  is  very  often  necessary  to  keep  a  man  in  addition  shoveling 
the  sand  from  the  trough. 

A  general  view  of  the  kaolin-washing  plant  at  the  Harris  kaolin  mine 


56  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

near  Webster  is  shown  in  Plate  III,  fig.  1.  At  the  end  of  the  shed 
on  the  right  are  the  four  sand  wheels.  Xext  to  these  conies  the  trough- 
ing, while  in  the  lowest  part  of  the  illustration  in  front  of  the  house  are 
the  settling  tanks.  In  the  background  along  the  foot  of  the  hill  are 
the  drying  racks. 

If  the  sand  is  finer  it  is  not  dropped  so  quickly,  but  distributed  more 
evenly  along  the  trough  and  does  not  clog  it  up  so  fast. 

The  zig-zag  arrangement  of  the  troughing  has  been  objected  to  by 
some,  as  it  produces  irregularities  in  the  current,  causing  the  sand  to 
bank  up  in  the  corners  at  the  bends,  and  also  at  certain  points  along  the 
sides  of  the  troughing.1 

The  effect  of  this  is  to  narrow  the  channel,  and  consequently  increase 
the  velocity  of  the  current,  thereby  causing  the  fine  sand  to  be  carried 
still  further  towards  the  settling  tanks. 

This  difficulty,  which  is  not  often  a  serious  one,  has  been  obviated 
either  by  having  the  troughing  straight,  or  by  allowing  the  water  and 
suspended  clay  as  it  comes  from  the  logwasher  to  pass  through  a  section 
of  straight  trough,  and  from  this  into  another  one  of  the  same  depth  but 
five  or  six  times  the  width  and  divided  by  several  longitudinal  partitions. 
The  water  and  clay  then  pass  into  a  third  section,  twice  as  wide  as  the 
second,  and  divided  by  twice  the  number  of  longitudinal  divisions. 

By  this  means  the  water  moves  always  in  a  straight  course,  but  as  it 
is  being  continually  spread  out  over  a  wider  space  it  flows  with  an  ever 
decreasing  velocity. 

By  the  time  the  water  has  reached  the  end  of  the  troughing  nearly 
all  of  the  coarse  grains  have  been  dropped  and  the  water  is  ready  to  be 
led  into  the  settling  vats,  but  as  a  further  and  necessary  precaution  the 
water  is  discharged  onto  a  screen  of  100  meshes  to  the  linear  inch. 
The  object  of  this  is  to  remove  any  coarse  particles  that  might  possibly 
remain,  and  also  to  remove  sticks  and  other  bits  of  floating  dirt  that 
are  sure  to  be  introduced. 

Two  kinds  of  screens  can  be  used:    1,  stationary,  and  2,  revolving. 

The  stationary  screen  is  simply  a  frame  covered  with  100-mesh  copper 
cloth  and  set  at  a  slight  angle.  The  water  and  suspended  kaolin  fall 
on  this  and  pass  through.  If  they  do  not  they  run  off  the  screen  and 
are  lost. 

A  slight  improvement  is  to  have  two  or  three  screens  overlapping, 
so  that  whatever  does  get  through  the  first  will  fall  on  the  second. 

If  the  vegetable  matter  and  sticks  are  allowed  to  accumulate  they 
clog  the  screen  up  and  nothing  will  run  through.  These  stationary 
screens  therefore  have  to  be  closely  watched. 

The  revolving  screens  are  far  better,  for  they  keep  themselves  clean. 

1  E.  Hotop.    Thonindustrie  Zeitung,  1893. 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  13,  PLATE  III. 


FIG.   1.- KAOLIN  WASHING  AND  DRYING  PLANT,   HARRIS  CLAY  CO.,  NEAR  WEBSTER. 
(See  also  page  61.) 


m 


FIG.   2.— KAOLIN    MINE,    HARRIS  CLAY   CO.,    NEAR   WEBSTER. 
Showing  method  of  sinking  pits  in  the  soft  kaolin.     (See  pages  53  and  60.' 


KAOLINS    OB    CHINA    CLAYS. 


57 


Such  a  screen  is  barrel-shaped,  and  the  water,  with  the  kaolin  in  sus- 
pension, is  discharged  into  the  interior  and  passes  outward  through  the 
screening.  As  the  screen  revolves,  the  dirt  caught  is  carried  upwards 
and  finally  drops;  but  instead  of  dropping  down  upon  the  other  side  of 
the  screen,  it  falls  upon  a  board  which  diverts  it  out  on  to  the  ground. 


Fig.  1. — Pump  used  in  forcing  kaolin  suspended  in  watek  from  the 
settling  vats  into  the  pkesses. 


The  settling  tanks  into  which  the  kaolin  and  water  are  discharged 
may  be,  and  often  are,  about  8  feet  wide  by  4  feet  deep  and  50  feet  or 
more  long.     As  soon  as  one  is  filled  the  water  is  diverted  into  another. 

The  larger  a  settling  tank,  the  longer  it  will  take  to  till  it  and  allow 
the  kaolin  to  settle,  and  delays  due  to  this  cause  are  expensive,  especi- 
ally when  the  market  takes  the  output  of  washed  kaolin  as  soon  as  it  is 
ready.     Too  many  small  tanks  increase  the  initial  cost  of  plant. 


5S  CLAY    DEPOSITS    EST    NORTH    CAROLINA. 

If  the  kaolin  settles  too  slowly,  alum  is  sometimes  added  to  the  water 
to  hasten  the  deposition.  When  the  kaolin  has  settled  most  of  the 
clear  water  is  drawn  off,  and  the  cream-like  mass  of  kaolin  and  water  in 
the  bottom  of  the  vat  is  drawn  off  into  the  slip  pumps  and  forced  by  them 
into  the  presses.  Figure  1,  on  the  preceding  page,  shows  a  form  of 
pump  used  for  this  purpose,  made  by  the  Turner,  Vaughn  and  Taylor 
Company  of  Cuyahoga  Falls,  Ohio. 

The  presses  consist  simply  of  a  series  of  flat  iron  or  wooden  frames 
between  which  are  flat  canvas  bags.  These  bags  are  connected  by 
nipples  with  the  supply  tube  from  the  slip  pumps.  By  means  of  the 
pressure  from  the  pumps  nearly  all  of  the  water  is  forced  out  of  the 
kaolin  and  through  the  canvas. 

"When  all  the  water  possible  is  squeezed  out  the  pressure  is  removed, 
the  press  opened,  and  the  sheets  of  semi-dry  kaolin  taken  out.  These 
sheets  are  rolled  up  and  put  on  the  racks  out  in  the  open  air  or  in  a 
steam-heated  room  to  dry. 

Plate  IY,  fig.  1,  shows  a  kaolin  filter  press  with  wooden  frame, 
and  fg.  2,  such  a  press  with  an  iron  frame.  The  latter  is  preferable, 
especially  in  climates  where  wood  decays  easily. 

In  a  plant  of  steady  and  moderate  capacity,  both  economy  and  ease 
may  be  practised  by  paying  a  little  attention  to  its  proper  arrangement. 
It  is  a  good  idea  to  have  cars  on  a  track,  or  an  endless  belt  run  past 
the  presses  and  drying  racks.  The  clay  can  then  be  taken  right  from 
the  presses  and  put  on  the  cars  or  belt  and  taken  right  from  them  and 
put  on  the  racks. 

As  for  every  ton  of  crude  kaolin  usually  only  about  two-fifths  or 
sometimes  one-quarter  of  a  ton  of  washed  kaolin  is  obtained,  the  impor- 
tance of  having  the  washing  plant  at  the  mines  will  be  easily  seen,  for 
it  avoids  the  hauling  of  60  to  70$  of  useless  sand,  which  has  to  be  washed 
out  before  the  kaolin  can  be  used  or  even  placed  on  the  market. 

DEPOSITS    OF    KAOLIN   IN   NORTH    CAROLINA. 

KAOLIN    IN    JACKSON    COUNTY. 

Near  Sylva. — North  Carolina  Mining  and  Manufacturine;  Co.  The 
kaolin  mine  of  this  company  is  two  miles  south  of  Sylva  on  the  mountain 
slope.  The  wall  rock  is  a  gneiss,  now  largely  decomposed  to  a  ferru- 
ginous clay.  The  kaolin  vein  cuts  this,  striking  about  N.  15°  E.  Its 
exact  width  is  not  known,  but  it  is  8  to  10  feet  in  places.  A  50-foot  shaft 
has  been  sunk  on  the  vein,  and  from  the  foot  drifts  have  been  run  in 
both  directions  along  the  vein.  This  drift  is  about  4  feet  wide  and 
6  feet  high.  That  running  to  the  east  from  the  shaft  is  about  150 
feet  long,  including  two  offsets  due  to  faulting  of  16  feet  each.     The 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  13,  PLATE  IV. 


FIG.   1.— WOODEN   FRAME  FILTER-PRESS-   FOR   REMOVING  THE  WATER   FROM  THE  WASHED  KAOLIN. 


FIG.  2.— IRON    FRAME    FILTER-PRESS,    FOR   REMOVING  THE  WATER    FROM   THE  WASHED   KAOLIN. 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  13,  PLATE  V. 


FIG.    1.— RESIDUAL   KAOLIN    DEPOSIT,    HARRIS  CLAY  CO.,   WEBSTER. 

View  looking  N.  E.  along  the  strike,  shows  only  half  of  the  vein,  the  rock  on  the  left  being  a  large  lens 
of  quartz  in  the  center  of  the  vein. 


FIG.   2 —RESIDUAL  CLAY    DEPOSIT,    NEAR   GROVER. 
Belonging  to  the  Powhatan  Clay  Manufacturing  Company.     'See  page  82.) 


KAOLINS    OK    CHINA    CLAYS.  59 

drift  running  west  has  gone  only  a  short  distance.  A  second  tunnel 
was  started  towards  the  east,  about  8  feet  above  the  bottom  of  the 
shaft. 

There  are  streaks  of  so-called  "  sand  "  at  several  points  in  the  mine, 
which  are  patches  of  only  partially  kaolinized  rock.  Several  tons  of 
fresh  feldspar  have  been  shipped  from  this  mine.  The  washed  clay  is 
very  fine-grained  with  no  grit.  Color  pure  white.  Very  smooth. 
Slakes  slowly  but  very  completely.  To  produce  a  workable  paste  40$ 
of  water  was  required.  This  paste  was  lean,  and  shrunk  8fc  in  drying 
and  4cr/o  in  burning,  giving  a  total  shrinkage  of  12$.  The  tensile  strength 
of  air-dried  briquettes  made  from  this  paste  was  15  lbs.  per  square  inch. 

Incipient  fusion  occurs  at  2200°  ¥.,  vitrification  at  2450°  F.,  and  vis- 
cosity at  2700°  F. 

The  clay  burns  to  a  pure  white,  smooth  body. 

The  shrinkage  in  drying  and  burning  is  3$  less  than  in  the  case  of 
the  kaolins  from  Florida.1 

The  following  is  the  analysis  of  this  clay: 

Analysis  of  washed  kaolin  (No.  57)  N.  C.  Mining  &  Mfg.  Co.,  two  miles  south  of  Sylva. 

Moisture 3.07 

Silica  (total) 44.08 

Alumina   36.26 

Ferric  oxide 1.S6 

Lime    43 

Magnesia    20 

Alkalies   50 

Water  (loss  on  ignition)   13.56 

Total    99.96 

Free  sand  5.75 

Total   fluxes 2.99 

From  this  analysis  we  get: 

Clay  substance   94.21 

Quartz  and  feldspar  5.75 

Specific  gravity   2.31 

The  insoluble  residue  was  not  analyzed  separately,  as  there  was  such 
a  small  amount  of  it. 

From  the  analysis  it  will  be  seen  that  the  clay  contains  a  high  per- 
centage of  clay  substance. 

Near  "Webster. — Harris  Clay  Company.  The  kaolin  deposit  of  this 
company  is  a  large  and  very  coarse  pegmatite  vein  or  dike  with  a  max- 
imum thickness  of  nearly  300  feet.  In  the  middle  there  is  a  large 
thick  lens  of  quartz.      (Plate  V,  fig.  1.) 

1  Langenbeck,  Chemistry  of  Pottery,  101. 


60  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

The  vein  runs  almost  north  and  south,  and  the  kaolin  is  of  high 
quality,  but  has  some  quartz  and  mica,  and  occasionally  garnet  mixed 
in  with  it. 

The  wall  rock  is  a  reddish,  fine-grained,  much  decomposed  gneiss, 
and  the  boundary  between  the  kaolin  and  gneiss  is  not  always  sharp. 
There  are  really  three  distinct  "  veins  "  of  kaolin  included  in  the  300 
feet  mentioned  above.  A  tunnel  was  driven  across  a  portion  of  the 
deposit  from  west  to  east,  and  the  materials  which  were  passed  through, 
together  with  their  thickness,  were  as  follows: 

Section  across  the  Harris  Kaolin  Mine  near  Webster. 

Kaolin  28  ft. 

Gneiss    23    " 

Quartz   32    " 

Kaolin  (exposed  in  V  tunnel) 56    " 

Kaolin  (bored  through)  21    " 

Kaolin  (exposed  in  shaft)   22    " 

182  ft. 

The  21  feet  exposed  in  boring  were  through  kaolin,  and  ended  in  a 
shaft  22  feet  wide  sunk  in  the  eastern  half  of  the  vein.  There  were 
several  feet  of  kaolin  beyond  this  shaft,  giving  over  100  feet  of  solid 
kaolin  in  the  eastern  half  of  the  vein.  The  tunnel  was  about  70  feet 
below  the  surface. 

The  pits  sunk  in  the  kaolin  vary  from  15-25  feet  in  width  and  80-100 
feet  in  depth.  The  deepest  thus  far  sunk  is  125  feet  through  solid 
kaolin.     (Plate  III,  fig.  2,  p.  56.) 

Since  April,  1896,  the  company  has  been  following  the  strike  of  the 
vein  down  the  hill,  toward  the  north,  and  has  sunk  several  new  pits  in 
this  direction. 

The  washed  kaolin  from  this  mine  is  smooth  to  the  taste  and  feeling 
and  shows  little  or  no  grit.  In  water  it  falls  slowly  but  completely  to 
a  fine  powder.  Forty-two  per  cent,  of  water  were  required  to  give  a 
workable  paste,  which  was  somewhat  lean.  It  shrunk  6#  in  drying 
and  4z/c  in  burning,  giving  a  total  shrinkage  of  10$.  The  average  ten- 
sile strength  of  air-dried  briquettes  was  20  lbs.  per  square  inch  with  a 
maximum  of  22  lbs.  Incipient  fusion  occurred  at  2300°  F.3  vitrifica- 
tion at  2500°  F.,  and  viscosity  above  2700°  F. 

The  clay  burns  to  a  white  body.  The  ultimate  and  rational  analysis 
of  this  kaolin  yielded  the  following  results: 


KAOLINS    OR    CHINA    CLAYS.  61 

Analysis  of  Kaolin  {No.  53),  Harris  Clay  Co.'s  Mine,  Webster. 

Washed  kaolin.  Portion  insoluble. 

Moisture    35  .... 

Silica    45.70  2.00 

Alumina    40.61  0.55 

Ferric  oxide    1.39  0.27 

Lime    0.45  .... 

Magnesia    0.09  

Alkalies    2.82  0.37 

Water  (loss   on   ignition) 8.98  .... 

Total    100.39  3.19 

Free    sand    3.19  

Total  fluxes    4.75  .... 

Specific  gravity 2.43  

This  gives  the  following  : 

Clay  substance  96.81 

Quartz    0.07 

Feldspar 3.12 

100.00 

The  kaolin  as  mined  is  discharged  into  the  upper  end  of  a  trough, 
along  which  it  is  washed  down  to  the  works.  It  is  discharged  into  the 
upper  end  of  the  washing  troughs,  and,  with  the  water,  passes  along 
under  5  sand  wheels,  which  extract  a  large  amount  of  the  fine  sand  and 
keep  the  trough  from  becoming  clogged.  The  kaolin,  sand  and  water 
then  pass  along  700  feet  of  troughing,  gradually  dropping  the  sand, 
until  the  settling  tanks  are  reached.  There  are  3  troughs,  4  pumps 
and  4  presses,  open-air  drying  racks,  and  a  steam-drying  room.  The 
capacity  of  the  works  is  24  tons  per  day  of  washed  and  dried  kaolin. 
(See  Plate  III,  p.  56.) 

The  washed  kaolin  has  to  be  hauled  four  miles  to  the  railroad  at  Dills- 
boro.  The  clay  is  dried  in  the  steam  chamber  in  three  days,  while  on 
the  racks  it  requires  two  weeks. 

Springer  Clay  Pit. — Geo.  Springer,  Jr.,  has  recently  opened  a  mine 
of  kaolin  on  the  property  of  AVm.  Buchanan,  one-half  mile  northeast  of 
Webster.  A  drift  has  been  run  in  from  the  side  of  the  hill  and  across 
the  vein.  In  this  tunnel  the  vein  of  kaolin  shows  up  25  feet  wide  and 
strikes  K  15°  W. 

Two  headings  have  been  run  north  and  south  from  the  drift  for  a 
distance  of  five  feet.  About  50  tons  of  the  crude  material  have  been 
thus  far  taken  out. 

The  kaolin  appears  to  be  of  excellent  quality,  but  the  presence  of 
some  coarse  angular  quartz  fragments  necessitates  it>  washing. 

Both  the  crude  and  washed  clays  were  tested,  and  the  two  series  of 
tests  are  given  in  parallel  columns  for  the  sake  of  comparison.  Xo.  54 
is  the  crude  material  and  Xo.  56  the  washed  kaolin. 


62  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Physical  tests  of  Kaolin,  washed  and  crude,  Springer  pit. 

Xo.  54.  No.  56. 

Crude  kaolin.  Washed  kaoliD. 

f  Coarse  to  fine.  Very  fine. 

Character (        gandy  Sm00th_ 

Slaking Fast  and  complete.     Slow  and  complete. 

Water  required  to  give  paste 32%  38% 

Plasticity  Lean.  Lean. 

Air  shrinkage  2  8 

Fire  shrinkage 4  4.5 

Average  tensile  strength 6  lbs.  23 

Maximum  tensile  strength 7  lbs.  24 

Condition  when  burned Porous.  Dense. 

Color  when  burned White.  White. 

Incipient  fusion 230(T  F.  2350'-  F. 

Vitrification  (incomplete)   2500°  F.  2550c  F. 

Viscosity    above  2700°  F.  above  2700°  F. 

Analysis  of  Kaolin,  Springer  pit,  }i  mile  X.  E.  of  Webster. 

No.  54*  Xo.  56. 

Crude         Insoluble  Washed         Insoluble 

kaolin.  residue.  kaolin.  residue. 

Moisture    25  2.05  

Silica 62.40  29.12  45.78  6.60 

Alumina    26.51  3.S5  36.46  


Ferric  oxide  1.14  .65  .28 

Ferrous  oxide   1.08 

Lime    57              .50 

Magnesia    01              .04 

Alkalies    9S  .90  .25 

Water  (loss  on  ignition)  .  .  8.S0               13.40 


Total       .100.66  34.52  99.S4 

Fluxes    2.70  2.15 

Specific  gravity     2.58  2.27 

From  the  rational  analysis  we  tet  the  following : 

Clay   substance       66.14  93.24 

Quartz 15.61) 

Feldspar    1S.91  /  b,bU 

It  is  plain  that  the  effect  of  the  washing  has  been  to  eliminate  the 
percentage  of  quartz  and  feldspar  and  relatively  increase  the  clay  sub- 
stance nearly  30$.      Of  the  fluxes  only  the  alkalies  have  been  decreased. 

KAOLIN    IN    MACON    COUNTY. 

Xear  "Wests  Mill. — On  the  land  of  Geo.  Brindel,  near  "Wests 
Mill,  is  a  deposit  of  kaolin  of  remarkable  whiteness,  which  burns  to  a 

*  Composition  of  Clay  substance  of  54: 

Silica 50.50  Alumina 34.24  Ferric  oxide 0  74 

Lime 0.36  Magnesia 0.01  Alkalies 0. 10 

AVater 13  35 


KAOLINS    OR    CHINA    CLAYS.  63 

pure  white  color,  showing  its  excellent  quality.  It  is  very  line-grained, 
free  from  grit,  and  shows  a  few  scattered  white  mica  scales.  It  slakes 
slowly  but  thoroughly. 

The  addition  of  31$  of  water  gave  a  workable  paste  of  the  usual  lean 
character.  The  bricks  made  from  this  paste  shrunk  6$  in  drying  and 
6$  in  burning,  giving  a  total  shrinkage  of  12$.  The  air-dried  bri- 
quettes had  an  average  tensile  strength  of  15  lbs.  per  square  inch  and 
a  maximum  of  18  lbs.  Incipient  fusion  occurs  at  2300°  F.,  vitrifica- 
tion at  2600°  F.,  and  viscosity  at  over  2700°  F.  The  clay  burns  to  a 
pure  white  body. 

The  following  analysis  of  the  unwashed  sample  shows  its  remarkable 
purity: 

Analysis  of  Kaolin  (Wo.  09)  from  Geo.  BrindeVs  land,  near  Wests  Mill. 

Crude  kaolin.       Insoluble  residue. 

Silica  (total)  53.10  15.23 

Alumina    33.06  0.07 

Ferric  oxide    1.18  0.46 

Lime     0.38  

Magnesia     0.0S  .... 

Alkalies    0.S3  0.S0 

Water  (loss  ou  ignition) 11.32  .... 

Total     99.95  16.56 

Total  fluxes   2.47 

Specific  gravity   2.31 

From  the  above  we  get  : 

Clay  substance  S3.39 

Quartz    14.9S 

Feldspar    1.5S 

Subtracting  the  second  column  from  the  first,  we  get  the  composition 
of  the  clay  substance,  which,  in  the  second  of  the  two  following  col- 
umns, is  recalculated  to  100.  The  clay  substance,  it  will  be  seen,  is 
nearly  pure  kaolinite,  but  with  a  slightly  greater  amount  of  alumina 
in  proportion  to  the  silica  than  is  called  for  by  the  formula  of  kaolinite: 

Composition  of  Clay  Substance  in  Kaolin  from  Wests  Mill. 

Silica 37.87  15.4] 

Alumina    32.99  39.51  i 

Ferric    cxide    0.72  0.St> 

Lime    0.3S  0.45 

Magnesia    0.0S  0.09 

Alkalies    0.03  «'.,.:; 

Water  (loss  on  ignition) 11.32  L3.5S 

83.39  99.98 


64  CLAY    DEPOSITS    IN    NOKTH    CAROLINA. 

KAOLIN    IN    MONTGOMERY    COUNTY. 

Eeae  Teoy. — Considerable  quantities  of  kaolin  have  recently  been 
discovered  4  miles  west  of  Troy,  Montgomery  county. 

From  the  various  outcrops  two  samples  were  tested. 

The  first  sample  forwarded  (No.  64)  was  a  darker  kaolin.  This  was 
a  fine-grained,  gritty  clay,  which  passes  almost  entirely  through  a  60- 
mesh  sieve.     It  slakes  easily  and  quickly  to  fine  grains. 

The  sample  when  washed  yielded  a  residue  of  40$,  which  is  probably 
somewhat  larger  than  would  be  obtained  in  actual  practice,  and  this 
washed  kaolin  required  30$  of  water  to  produce  a  workable  paste  that 
was  lean  to  the  feeling.  This  paste  shrunk  3$  in  drying  and  an  addi- 
tional 10 '$  in  burning,  giving  a  total  shrinkage  of  13$.  The  average 
tensile  strength  of  air-dried  briquettes  was  9  lbs.  per  square  inch  with 
a  maximum  of  12  lbs.  per  square  inch.  Incipient  fusion  occurred  at 
2100°  F.,  vitrification  at  2300°  F.,  and  viscosity  at  2500°  F. 

The  clay  burns  to  a  very  pale  buff. 

The  second  sample  forwarded  was  a  white  kaolin  (No.  68)  and  does 
not  possess  the  grayish  tint  which  the  other  does.  It  shrank  3$  in  dry- 
ing and  9$  in  burning,  giving  a  total  shrinkage  of  12$.  The  air-dried 
briquettes  had  an  average  tensile  strength  of  10  lbs.  per  square  inch 
with  a  maximum  of  12  lbs.  Incipient  fusion  occurs  at  2100°  F.,  vitri- 
fication at  2300°  F.,  and  viscosity  at  2500°  F.  The  kaolin  burns  to  a 
deeper  buff  than  the  preceding  one. 

The  coloration  of  these  two  kaolins  is  against  their  use  for  white- 
ware,  but  they  might  be  used  for  higher  grades  of  stoneware,  encaustic 
tiles,  or  in  the  body  of  refractory  wares  for  laboratory  use. 

The  crude  white  kaolin  was  at  first  tested,  as  its  snow-white  color 
suggested  that  it  might  burn  white  and  to  a  dense  body  without  further 
treatment.  The  results  obtained  were  so  similar  to  those  of  the  washed 
white  kaolin  that  they  are  simply  given  in  the  appended  table.  The 
tensile  strength  of  the  crude  material  was  a  few  pounds  greater  and  the 
shrinkage  in  burning  three  per  cent.  less. 

An  examination  of  the  following  analyses  indicates  the  rather  high 
iron  percentage  which  accounts  for  the  color  of  the  burned  clay.  A 
comparison  of  the  analysis  of  the  washed  and  crude  kaolin  also  points 
out  that  the  percentage  of  sand  has  been  reduced,  but  none  of  the  iron 
removed. 

In  the  following  analyses  ~No.  64a  represents  the  darker  kaolin  (crude) 
from  4  miles  west  of  Troy,  ~Ro.  64  this  darker  kaolin  washed,  and  No. 
68  the  white  kaolin  washed  from  the  same  localitv. 


j 


KAOLINS    OR    CHINA    CLAYS.  65 

Analyses  of  Kaolin  4  miles  W.  of  Troy,  Montgomery  Go. 

No.  64a.  No.  64.  No.  68. 

Moisture   48  .53  .75 

Silica    90.13  86.03  63.10 

Alumina    4.99  6.46  23.33 

Ferric  oxide 1.86  2.14  2.97 

Lime 13  .17  .15 

Magnesia 01  .04  .09 

Alkalies   1.03  1.00  1.90 

Water  (loss  on  ignition) ....   1.93  2.90  7.65 

Total    100.56  99.27  99.94 

Insol.   residue    85.85  78.54  41.08 

Total  fluxes    3.03  3.35  5.11 

Specific  gravity 2.47  2.32  2.34 

Analyses  of  insoluble  residue  from  the  above. 

No.  64a.  No.  64.  No.  68. 

Silica    84.64  77.25  38.25 

Alumina    20  .30  .85 

Ferric  oxide 37  .26  .46 

Alkalies   64  .73  1.52 

85.85  78.54  41.08 

From  the  above,  by  a  rational  analysis,  we  get  the  percentages  of  the 
mineral  ingredients  as  follows: 

Mineral  Composition  of  Kaolin  4  miles  W.  of  Troy,  N.  C. 

No.  64a.  No.  64.  No.  68. 

Clay   substance    14.71  20.83  58.92 

Quartz    83.94  76.20  35.27 

Feldspar    1.91  2.34  5.81 

Composition  of  the  clay  substance  in  the  above. 

No.  61a.  No.  64. 

Silica    38.58  43.46 

Alumina    33.66  30.04 

Ferric  oxide 10.46  9.30 

Lime   91  .84 

Magnesia    07  .19 

Alkalies    2.70  1.33 

Water  (lost  on  ignition)   13.56  14.35 

99.94  99.51 

KAOLIN    IN    RICHMOND    COUNTY. 

Near  Bostick. — Considerable  residual  kaolin  has  recently  been 
found  on  the  property  of  Robert  W.  Steele,  near  Bosticks  Mills,  14 
miles  north  of  Rockingham,  Richmond  county.  A  number  of  tesl 
pits  have  been  sunk  and  the  exploitations  indicate  the  presence  of  an 

5 


66  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

abundant  amount  of  material.  The  deposit  could  be  readily  trans- 
ported to  market.  It  is  two  miles  from  the  end  of  a  lumber  railroad, 
and  after  hauling  to  this  point  the  lumber  company  would  transport  it 
to  the  railroad  at  Hoffman,  a  distance  of  12  miles,  for  not  exceeding 
50  cents  a  ton;  or  this  timber  railroad  could  be  extended  easily  and 
cheaply  to  the  kaolin  deposit. 

The  first  point  at  which  the  kaolin  appears  is  one  mile  south  of  Bost- 
ick  P.  O  and  near  Christopher  Bostick's  cabin,  where  it  crops  out  for 
a  distance  of  fifty  feet  in  a  ditch  by  the  roadside.  It  is  next  seen 
on  the  opposite  side  of  the  road,  at  base  of  hill,  but  between  these  two 
exposures  is  a  red  clay  resulting  from  the  decomposition  of  schistose 
rock. 

Just  east  of  the  first-mentioned  exposure,  and  in  the  woods  about  100 
feet  from  the  road,  a  test  pit  four  feet  square  has  been  sunk  (No.  21). 
This  showed  lj  feet  overburden  and  then  3  feet  kaolin.  The  pit  had 
been  sunk  10  feet  through  kaolin,  but  had  caved  in.  About  30  feet 
from  this  another  pit  was  sunk  to  a  depth  of  12  feet.  This  also  shows 
the  kaolin  from  one  foot  below  the  surface  down  to  the  bottom  (No.  20). 
Several  other  small  pits  have  been  sunk  within  a  radius  of  75  feet,  and 
all  penetrated  the  kaolin.  The  material  is  fine-grained,  with  compara- 
tively few  angular  fragments.  There  are  scattered  stains  of  iron,  but 
these  may  disappear  with  depth. 

Another  series  of  pits  (No.  22)  have  been  sunk  on  Mr.  Chapel's  land, 
one  mile  due  west  of  No.  21.  These  pits  were  sunk  to  a  depth  of  10 
feet,  and  the  kaolin  appeared  at  18  inches  from  the  surface  and  con- 
tinued to  bottom  of  pits.  This  kaolin  is  whiter  than  that  at  21.  Be- 
tween the  two  deposits  there  is  a  shallow  valley,  and  it  is  not  known 
whether  21  and  22  are  portions  of  one  vein  or  not. 

Samples  of  Nos.  20,  21  and  22  were  tested  in  their  crude  condition, 
and  Nos.  20  and  22  were  also  washed. 

No.  20  is  a  fine-grained  kaolin  with  little  coarse  grit,  which  slakes 
slowly  but  completely  to  a  fine-grained  mass.  It  required  27.7$  of 
water  to  give  a  workable  paste,  which  shrank  4$  in  drying  and  9$  in 
burning.  Incipient  fusion  occurs  at  2250°  F.,  vitrification  at  2500'  F., 
and  viscosity  at  2700°  F.  The  average  tensile  strength  of  air-dried 
briquettes  was  10  lbs.  per  square  inch  with  a  maximum  of  14  lbs.  per 
square  inch.  The  clay  burned  to  a  dense  body  with  slightly  yellowish 
tint. 

No.  21  slaked  the  same  as  20.  It  required  26$  of  water  to  make  a 
workable  but  lean  paste,  which  shrunk  3.5$  in  drying  and  8#  in  burn- 
ing. Incipient  fusion  occurred  at  2300°  F.,  vitrification  at  2500°  F., 
and  viscosity  at  2700°  F.  The  clay  burns  to  same  tint  as  No.  20.  Its 
average  tensile  strength  was  13  lbs.  per  square  inch,  with  a  maximum 
of  16  lbs.  per  square  inch. 


KAOLINS    OR    CHINA    CLAYS.  67 

~No.  22  is  a  somewhat  porous,  fine-grained  white  clay  with  compara- 
tively little  grit,  which  slakes  slowly  but  completely  to  fine  grains. 

It  required  27.7$  of  water  to  make  a  workable  but  lean  paste.  This 
paste  shrunk  4=fc  in  drying  and  an  additional  8$  in  burning.  The  aver- 
age tensile  strength  of  the  air-dried  briquettes  was  15  lbs.  per  square 
inch  with  a  maximum  of  16  lbs. 

Incipient  fusion  occurs  at  2250°  F.,  vitrification  at  2450°  F.,  and  vis- 
cosity at  over  2700°  F. 

The  following  analyses  of  these  three  samples  (crude  kaolin)  were 
made: 

Analyses  of  Kaolin  near  Bosticks  Mills,  14  miles   ~N.  of  Rockingham,  Richmond  Co. 

No.  21.  No.  20.*  No.  22. 

Crude  Insol.  in  Crude  Insol.  in  Crude  Insol.  in 

Kaolin.  H2S04  etc.  Kaolin.  H2S04  etc.  Kaolin.  H2S04  etc. 

Silica    68.15  47.45  70.63  48.10  73.70  62.33 

Alumina    19.99  1.70  21.81  3.24  16.03            

Ferric  oxide    1.86  .20  1.49  .56  1.57            

Lime    13  .20  .38            

Magnesia    16  .29  .47            

1  Na20  .72  ") 

Alkalies    2.85  1.35  1.45   I ._  "    nA      y      1.90  

J    K2G  .24     J 

Moisture    17  ....  .08  ....  ....  .... 

Water  (loss  on  ignition).   4.70  4.04  4.33  .... 


Total    98.01  50.70  99.99  52.S6  98.38  62*33 

Total  fluxes   5.00  3.43  4.32  

Specific   gravity    2.52  2.41  2.43  

From   the    above   we   obtain   the    mineralogical   composition    of   the 
kaolins  as  being: 

Mineral  composition  of  Kaolin  near  Bosticks  Mills. 

No.  21.  No.  20.  Mo.  22. 

Clay  substance   49.30  47.14  36.05 

Feldspar     9.20  )  16.13 


S 


Quartz     .41.50/  36.^° 

A  5 -lb.  sample  of  No.  20  was  washed.  The  settlings  amounted  to 
4r.Ofc7  which  is  probably  somewhat  larger  than  would  be  obtained  in 
actual  practice.  The  washed  kaolin  required  26$  of  water  to  give  a 
workable  paste  that  was  lean  but  smooth.     This  paste  shrunk   3$  in 


*  Composition  of  Clay  Substance  of  No.  20: 

Silica — 

47.88 

did  04 

Ferric  oxide  ... 

1.90 

Lime 

0.42 

0.80 

Alkalies 

l.di 

Water 

a  50 

99.46 


68  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

drying,  and  there  was  an  additional  shrinkage  of  9$  in  burning.  In- 
cipient fusion  occurred  at  2250°  F.,  vitrification  at  2450 J  F.,  and 
viscosity  at  over  2700°  F.  There  was  a  faint  yellowish  tint  to  the 
burned  ware. 

Sample  ~No.  22  was  also  washed.  The  washed  material  was  35^  of 
the  original  mass.  It  required  29$  to  give  a  lean  but  workable  paste 
that  shrunk  4$  in  drying  and  7$  in  burning,  giving  a  total  shrinkage 
of  life  The  air-dried  briquettes  had  an  average  tensile  strength  of 
8  lbs.  per  square  inch  and  a  maximum  of  11  lbs.  Incipient  fusion 
occurs  at  2250°  F.,  vitrification  at  2450°  F.,  and  viscosity  at  over  2700° 
F.  The  clay  when  washed  was  pure  white,  but  when  burned  had  the 
faintest  yellow  tint. 

An  analysis  was  made  of  the  washings  from  'No.  20  and  yielded  the 
following  percentages : 

Analysis  of  Washings  from  Kaolin  (No.  20),  near  Bosticks  Mills. 


Total  portion.        Insoluble  portion. 

Silica    ...., 71.12  44.38 

Alumina    19.61 

Ferric  oxide 2.18 

Lime   17 

Magnesia   08 

Alkalies    2.48 

Water  (loss  on  ignition) 4.33 


Total    99.97  45.67 

From  the  above  we  get  the  following: 

Mineral  composition  of  washings  from  the  Bostick  Kaolin  No.  20. 

Clay  substance 54.30 

Quartz    43.85 

Feldspar    1.82 

Composition  of  clay  substance  from  the  Bostick  Kaolin,  sample  No.  20. 

Silica    49.33 

Alumina 35.90 

Ferric  oxide 3.15 

Lime   31 

Magnesia 14 

Alkalies    3.15 

Water  (loss  on  ignition)  S.00 


Total    99.98 

USES    OF    THE    NORTH    CAROLINA    KAOLINS. 

The  foregoing  tests  of  the  kaolins  from  several  localities  are  to  be 
looked  upon  as  very  promising,  for  they  indicate  the  presence  of  much 
material  of  a  high  grade. 


KAOLINS    OR    CHINA    CLAYS.  69 

It  would  be  possible'  to  make  comparisons  of  the  North  Carolina 
kaolins  with  those  from  other  localities,  but  such  comparisons  have 
little  practical  value,  unless  the  chemical  and  physical  characters  of 
each  clay  are  known.  Many  ultimate  and  rational  analyses  of  foreign 
kaolins  have  been  published,  but  few  physical  tests  are  given.1 

As  a  matter  of  interest,  some  of  the  North  Carolina  kaolins  may  be 
compared  with  celebrated  foreign  ones  which  are  used  in  the  manu- 
facture of  the  highest  grades  of  porcelain. 

In  the  following  columns  the  analyses,  No.  a  (53)  and  No.  b,  are 
those  of  washed  kaolin  from  the  mine  of  the  Harris  Clay  Co.,  the  first 
analyzed  by  Chas.  Baskerville,  the  second  by  C.  Langenbeck.2  Number 
c  is  an  analysis  of  the  well-known  kaolin  from  Zettlitz,  near  Carlsbad, 
in  Bohemia. 

Analyses  of  Kaolins  :   Webster,  N.  C.  (a  and  b)  and  Zettlitz  (c). 

Nos.  a  (53).  No.  T>.  No.  c. 

Silica    . 45.70  45.80  46.82 

Alumina    40.61  39.20  38.49 

Water  (loss  on  ignition) 8.98  13.11  12.86 

Ferric  oxide    1.39  .40  1.09 

Lime     45  .45  .... 

Magnesia    09  .15  tr. 

Alkalies    2.82  .92  1.40 

100.04  100.03  100.66 

The  washed  white  kaolin  from  4  miles  west  of  Troy,  N.  C.  (No.  68), 
is  interesting  to  compare  with  a  German  kaolin  from  Sennewitz,  near 
Halle,  (d)  and  which  is  used  at  Berlin  for  the  manufacture  of  porcelain.3 
The  two  are  very  similar  in  their  ultimate  composition,  but  disagree 
strongly  when  their  rational  analyses  are  compared. 

Analyses  of  Kaolin  from  Troy,  JV.  G.  (68)  and  Sennewitz,  Germany  (d). 

No.  68.  No.  d. 

Moisture    75  .... 

Silica    63.10  64.87 

Alumina    23.33  23.83 

Water  (loss  on  ignition) 7.65  8.36 

Ferric  oxide  2.97  .83 

Lime    15  .... 

Magnesia    09  .50 

Alkalies    1.90  1.39 

99.94  99.7S 

Clay    substance    5S.92  63.77 

Quartz    35.27  35.50 

Feldspar    5.81  .73 

1  ThoDindustrie  Zeitung,  1893,  p.  1311.        -Chemistry  of  Pottery.        3Sefr.  Ges.  Sohr.,  p.  50. 


70  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

The  North  Carolina  kaolins,  which  contain  under  one  per  cent,  of 
ferric  oxide,  are  perfectly  well  adapted  to  the  manufacture  not  only  of 
white  earthenware,  but  also  of  the  best  grades  of  porcelain.  Those 
with  1-J  to  2$  of  ferric  oxide  could  no  doubt  be  used  for  lower  grades 
of  white  earthenware,  while  those  containing  2  to  2^  of  ferric  oxide 
might  be  utilized  for  mixing  with  fire-clays  in  the  manufacture  of 
refractory  apparatus. 

Kaolin  containing  very  little  grit,  which  would  be  the  case  when  it 
had  a  very  large  percentage  of  clay  substance,  is  eagerly  sought  after 
by  paper  manufacturers.  Kaolin  is  also  used  in  the  manufacture  of 
ultramarine.  For  this  purpose  it  should  be  as  low  in  iron  and  lime 
as  possible.  An  excess  of  silica  is  undesirable,  but  if  too  little  is 
present  it  may  be  added  in  the  form  of  finely  powdered  quartz. 


31 


CHAPTEE  VI. 
POTTERY  CLAYS  IN  NORTH  CAROLINA. 

THE    POTTERY   INDUSTRY. 

The  pottery  industry  of  North  Carolina  has  thus  far  been  confined 
entirely  to  small  potteries  of  perhaps  25,000  gallons  annual  capacity, 
whose  trade  is  mostly  local.  There  are  between  forty  and  fifty  of  these 
small  potteries  in  the  state,  and  most  of  them  are  located  near  Jugtown 
and  Blackburn  in  Catawba  county,  and  Henry  in  Lincoln  county. 
There  are  others  scattered  over  the  state,  as  at  Wilkesboro,  Wilkes 
county,  two  miles  north  of  Morganton,  Burke  county,  and  several 
other  localities. 

All  of  the  potteries  in  Lincoln  and  Catawba  counties  obtain  a  large 
amount  of  their  clay  from  the  lowlands  along  the  Clarke  river  (south 
fork  of  Catawba)  two  miles  north  of  Lincolnton,  some  of  them  having 
to  haul  it  14  miles.  They  pay  50  cents  a  ton  for  it,  and  generally  haul 
the. clay  on  their  return  from  a  peddling  trip,  when  their  wagons  would 
otherwise  be  empty. 

The  clays  used  for  pottery  purposes  in  North  Carolina  are  the  finer 
aluminous  sediments  underlying  the  river  terraces  to  be  found  in  many 
of  the  broader  valleys,  and  the  better  ones  are  generally  found  near  the 
shore  line  of  the  terrace.  These  terrace  deposits  of  fine-grained,  plastic 
clay  are  common,  and  with  an  increasing  demand  for  pottery  clays 
in  the  state,  an  abundance  of  the  necessary  material  will  probably  be 
found  close  at  hand. 

In  addition  to  the  clay  deposits  underlying  the  terraces  along  Clarke 
river,  especially  north  of  Lincolnton,  which  have  already  been  men- 
tioned, the  Catawba  river,  which  flows  by  Morganton  and  Catawba, 
and  thence  southward  past  Mt.  Holly,  has  also  a  marked  terrace  devel- 
opment; and  the  clays  north  of  Morganton  have  already  been  used  for 
pottery  manufacture. 

A  third  series  of  deposits  of  terrace  clays  is  to  be  found  along  the 
Yadkin  river. 

Those  at  "Wilkesboro  emphasize  the  importance  of  making  a  rather 
thorough  search  for  the  proper  kind  of  clay,  for  the  material  found 
there  at  one  point  is  only  suitable  for  brick,  while  one-quarter  of  a  mile 
further  it  is  eminently  plastic,  smooth,  and  burns  to  a  dense  hard  body, 
just  such  as  is  needed  for  stoneware. 


72  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

REQUISITES    OF   A   POTTERY    CLAY. 

This  term  is  meant  to  include  the  lower  grades  of  earthenware  and 
stoneware  clay.  For  common  earthenware,  such  as  flower-pots,  almost 
any  red-burning,  plastic  clay  will  suffice,  if  it  permits  turning  on  the 
potter's  wheel  and  burns  to  a  good  red  but  not  vitrified  body. 

It  is  also  possible  to  make  a  very  serviceable  grade  of  earthenware 
from  calcareous  clays,  with  up  to  20  or  30  per  cent,  of  calcium  car- 
bonate (provided  it  is  finely  divided  and  evenly  distributed  through  the 
clay),  and  cover  the  ware  with  an  easily  fusible  glaze  of  clay,  clay  and 
lead,  or  a  mixture  of  fusible  compounds.  The  majolica  wares  made  in 
Italy  and  Germany  are  made  from  such  clays. 

Stoneware  clays  require  a  little  more  attention. 

They  should  possess  good  plasticity  in  order  to  permit  molding  or 
turning  without  cracking. 

Their  tensile  strength  should  be  preferably  not  less  than  125  lbs.  or 
150  lbs.  per  square  inch. 

They  should  not  shrink  excessively  in  burning,  and  should  burn  to  a 
dense  vitrified  body  at  a  temperature  of  2000°  F.  or  2100°  F.  if  pos- 
sible. The  lower  temperature  of  vitrification  is  of  course  an  important 
item  of  economy.  For  the  same  reasons  the  clay  should  permit  of  rapid 
drying.     It  should  also  be  smooth  and  as  free  from  grit  as  possible. 

The  fluxing  impurities  in  a  stoneware  clay  should  be  sufficiently  high 
to  produce  a  vitrified  body.  Iron  is  a  desirable  coloring  ingredient. 
Lime,  if  in  small  amounts,  2-3$,  is  not  very  objectionable,  but  a  large 
percentage  may  bleach  the  iron  color,  decrease  the  shrinkage  and  in- 
crease the  fusibility.  Calcium  sulphate  is  undesirable,  for  its  dissocia- 
tion at  high  temperatures  may  cause  blistering. 

It  is  frequently  found  that  better  results  can  be  obtained  by 
mixing  two  different  clays,  the  one  furnishing  stiffness  and  low  shrink- 
age, the  other  plasticity  and  easier  fusibility.  This  is  done  by  all  of 
the  North  Carolina  potters,  the  two  clays  which  they  use  being  mixed 
in  equal  proportions,  although  in  their  case  the  chief  difference  of  the 
clays  used  is  in  plasticity  and  stiffness. 

Clays  for  making  yellow  ware  are  generally  low  grade  fire-clays 
which  burn  to  a  buff  color.  They  are  usually  washed  to  eliminate  any 
coarse  sand  and  pyrite  nodules  which  they  may  contain.  This  is  gen- 
erally done  in  a  circular  vat  or  "  blunger,"  in  which  there  revolve 
stirrers,  as  mentioned  under  "  The  Preparation  of  Kaolin  "  (page  54). 

Yellow  ware  is  first  molded  and  burned  to  incipient  fusion,  the  trans- 
parent or  opaque  glaze  applied  and  the  ware  burned  again. 

Some  of  the  shale  clays  associated  with  the  coal  seams  in  North 
Carolina  might  answer  for  this  purpose,  but  they  have  not  yet  been 
tested. 


POTTERY    CLAYS    IN    NORTH    CAROLINA.  73 

STONEWARE    MANUFACTURE. 

The  methods  at  present  employed  within  the  State  are  somewhat 
crude,  but  best  adapted,  perhaps,  to  the  size  of  the  plant  and  available 
capital. 

The  clay  is  mixed  in  a  vertical  box,  in  which  there  is  set  a  shaft  with 
iron  cross-pieces.  This  shaft  is  turned  by  horse-power,  and  the  clay 
becomes  mixed  by  the  action  of  the  iron  arms.  Before  molding,  the 
clay  is  further  wedged.  It  is  tempered  to  quite  a  soft  paste,  whose 
total  shrinkage  in  drying  and  burning  is  20-25^,  according  to  the  potters. 
The  molding  is  done  on  the  old-fashioned  "  kick-wheel,"  and  the  green 
ware  dried  on  shelves  set  over  a  long,  low,  hot-air  flue  in  the  centre  of 
the  room. 

The  wares  are  burned  in  a  long,  low  kiln  resembling  a  muffle  in 
form.  The  glaze  is  either  old  glass  or  furnace  slag  ground  fine  and 
applied  in  the  form  of  a  slip.  The  glass  is  put  on  the  wares  set  in  the 
upper  end  of  the  kiln,  as  it  melts  easier,  while  the  ware  set  in  the  lower 
end  of  the  kiln  is  coated  with  the  ground  slag. 

If  a  pottery  clay  possesses  all  the  requisite  chemical  and  physical 
characters  but  is  gritty,  it  is  often  possible  to  remove  the  grit  by  wash- 
ing. This  is  best  done  in  a  circular  tub  in  which  there  revolve  stirring 
arms,  as  mentioned  under  the  head  of  kaolin  washing.  The  water,  with 
suspended  clay,  is  drawn  off  and  the  latter  allowed  to  settle  in  tanks. 
The  clear  water  is  then  drawn  off  and  the  clay  can  be  dried  by  steam 
or  in  the  sun.  Sandy  clays  will  dry  quicker,  but  they  do  not  burn  to 
as  dense  a  body. 

None  of  the  North  Carolina  potters  use  Albany  slip  for  glazing  their 
ware.  If  they  did  the  product  would  be  far  more  sightly  than  it  is 
now.  The  crude  glaze  which  they  use  is  cheap,  but  it  cracks  very 
soon.  "With  a  little  experimenting  of  the  proper  nature  it  would  be 
possible  to  find  glazes  adaptable  to  the  clays  now  being  used.  This, 
together  with  the  application  of  improved  methods  and  some  care, 
would  enable  the  North  Carolina  potter  to  put  a  far  better  grade  of 
ware  on  the  market,  and  sell  it  at  a  correspondingly  increased  price. 
At  present  nearly  all  of  the  earthenware  and  stoneware  used  in  the 
larger  towns  and  cities  of  North  Carolina  comes  from  other  states. 

The  molding  is  all  done  by  hand,  and  in  the  present  state  of  the 
industry  plaster  molds  have  not  been  deemed  necessary. 

As  has  been  already  stated,  many  of  these  river  clays  are  well  adapted 
to  stoneware  manufacture,  and  would  give  a  far  better  product  than  is 
now  being  made.  Their  temperature  of  vitrification  is  also  high  enough 
to  bear  the  application  of  Albany  slip  as  a  glazing  material. 

The  Albany  slip  is  an  impure  fusible  clay  found  in  the  Eudson  river 
valley  in  New  York  state.     It  vitrifies  at   ls<><>    F.  and  forms  a  brown, 


74 


CLAY    DEPOSITS    IN    NORTH    CAROLINA. 


evenly  colored  coat.     No  other  clay  has  yet  been  found  which  has  these 
qualities  of  such  constancy. 

In  larger  stoneware  factories  the  kick-wheel  is  found  insufficient. 
For  the  ordinary  symmetrical  shapes  a  common  potter's  wheel  can  be 
used,  operated  by  steam  power.  Crocks,  jugs  and  similar  articles  are 
molded  on  this,  the  potter  throwing  a  lump  of  clay  on  the  revolving 
wheel  and  then  deftly  working  it  up  into  the  desired  form  simply  by 
using  his  fingers. 


Fig.  2. — The  Potters'  Jolly  Wheel,  No.  8. 

Many  articles  are  molded  on  a  jolly  wheel.  With  this  a  plaster  of 
Paris  mold  is  used  to  form  the  article.  The  mold  is  set  on  the  wheel 
and,  while  being  revolved,  a  lump  of  the  tempered  clay  is  thrown  into 
it  and  worked  out  in  a  thin  layer  over  the  interior  surface  of  the  mold. 


POTTERY    CLAYS    IN    NORTH    CAROLINA.  75 

The  mold  is  then  set  aside  to  dry,  and  the  clay  shrinks  from  the  mold 
and  hardens  sufficiently  to  be  lifted  out.  Fig.  2  shows  a  jolly  made 
by  the  Turner,  Vaughn  &  Taylor  Co.,  of  Cuyahoga  Falls,  Ohio. 

The  speed  of  drying  depends  on  the  clay.  If  possible,  the  drying  is 
done  in  a  steam-heated  room  for  a  number  of  hours  until  the  ware  is 
dry  enough  to  be  burned.  If  slip  glaze  is  used  the  ware  has  to  be 
first  dipped  into  it  and  once  more  dried  before  burning,  but  if  salt  glaze 
is  used  the  ware  is  put  directly  in  the  kiln. 

The  quicker  the  drying  and  burning  which  a  clay  will  permit  with- 
out cracking  the  more  economical  it  is  to  use  it. 

Very  plastic  clays  have  to  be  dried  slowly  to  prevent  cracking,  but 
this  difficulty  may  be  overcome  by  the  admixture  of  more  sandy  ones. 

Burning  may  be  done  in  circular  kilns,  which  are  either  up-draft  or 
down-draft  in  their  action.  The  burning  and  cooling  take  from  5-8 
days,  depending  on  the  clay. 

The  water-smoking  can  generally  be  carried  on  rapidly,  but  the  cool- 
ing should  not  be  hurried,  to  avoid  cracking. 

POTTERY    INDUSTRY    IN    BURKE    COUNTY. 

Near  Morganton. — Three  miles  north  of  Morganton  is  the  North 
Carolina  pottery,  at  present  inoperative,  but  the  plant  is  one  of  the 
largest  in  the  State.  The  clay  which  it  is  claimed  was  alone  used  is 
on  Manly  McDowell's  property,  li  miles  west  of  Morganton  and  along 
the  road,  an  eighth  of  a  mile  from  the  Catawba  river. 

This  clay  (No.  51)  directly  underlies  the  terrace  surface  and  is  a  fine- 
grained, gritty,  soft  clay,  overlain  by  18  inches  to  2  feet  of  yellow  loam. 
The  bed  of  clay  is  6-7  feet  thick. 

The  addition  of  36$  of  water  gave  a  stiff,  somewhat  smooth,  but 
rather  lean  mass,  which  shrunk  9.6$  in  drying  and  -1.5;/  in  burning, 
giving  a  total  shrinkage  of  14.1$. 

The  air-dried  briquettes  of  this  clay  had  an  average  tensile  strength 
of  60  lbs.  per  square  inch  with  a  maximum  of  81  lbs. 

Incipient  fusion  occurs  at  1950°  F.,  vitrification  at  2100°  F.,  and 
viscosity  at  2250°  F.     The  clay  burns  red. 

The  analysis  of  the  clay  is  as  follows: 

Analysis  of  Pottery  Clay  [No.  51),  Manly  McDowell's,  near  Morganton. 

Moisture    1.68 

Silica  (total)   69.58 

Alumina    14.03 

Ferric  oxide   6.4 1 

Lime   40 

Magnesia   27 

Alkalies    1.65 


76  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Water  (loss  on  ignition)   5.73 

Total    99.75 

Clay  substance    45.47 

Free  sand    54.28 

Total  fluxes  8.73 

Specific  gravity    2.59 

It  is  manifestly  impossible  that  pottery  could  have  been  made  from 
this  clay  alone,  on  account  of  its  low  binding  power,  and  a  more  plastic 
material  must  have  been  mixed  with  it. 

POTTERY    INDUSTRY    IN    CATAWBA    COUNTY. 

Near  Blackburn. — Many  of  the  potters,  especially  those  at  Black- 
burn, use  a  highly  plastic,  dark-colored  clay  obtained  two  miles  north- 
west of  Blackburn  on  the  property  of  M.  Finger.  This  clay  is  smooth, 
dense,  and  slakes  slowly  to  irregular,  scaly  flakes.  There  is  a  noticeable 
amount  of  organic  matter  present  in  it. 

The  addition  of  30^  of  water  was  required  to  give  a  workable  mud, 
which  was  very  plastic.  This  paste  shrunk  12$  in  drying  and  an  addi- 
tional 7fo  in  burning,  giving  a  total  shrinkage  of  19$.  The  briquettes 
made  from  this  clay  had  when  air-dried  an  average  tensile  strength  of 
148  lbs.  per  square  inch  and  a  maximum  of  200  lbs.  Incipient  fusion 
occurred  at  1950°  F.,  vitrification  at  2100°  F.,  and  viscosity  at  2250°  F. 

The  clay  burns  to  a  grayish  brown  body  of  good  density. 

The  analysis  of  the  clay  is  as  follows: 

Analysis  of  Pottery  Clay  (No.  50),  2  miles  JJT,  W.  of  Blackburn. 

Moisture 2.08 

Silica  (total)    50.17 

Alumina    28.77 

Ferric  oxide   2.88 

Lime    05 

Magnesia 22 

Alkalies    1.04 

Water  (loss  on  ignition)   14.03 

Total    99.24 

Clay   substance    73.19 

Free  sand    26.05 

Total  fluxes    4.19 

Specific  gravity    2.35 

The  high  percentage  of  loss  on  ignition  is  due  to  the  several  per  cent, 
of  organic  matter  in  the  clay.  This  also  increases  the  plasticity  and 
adds  somewhat  to  the  air  shrinkage. 


POTTERY  CLAYS  IN  NORTH  CAROLINA.  7  < 

POTTERY  INDUSTRY  IN  LINCOLN  COUNTY. 

Near  Lincolnton. — The  clay  along  the  Clarke  river,  northwest  and 
north  of  Lincolnton,  supplies  nearly  fifty  potters  in  Catawba  and  Lin- 
coln counties. 

The  material  is  a  fine-grained  gray  clay  with  occasional  yellow  iron 
stains.  Two  samples  were  tested,  No.  61  from  the  pits  at  end  of  lane 
on  T.  Rhodes'  property  two  miles  northwest  of  Lincolnton,  and  No.  49 
from  about  one-quarter  mile  farther  up  the  river. 

No.  61  is  a  fine,  gritty  clay  with  scattered  mica  scales.  It  slakes 
slowly.  The  addition  of  35$  of  water  gave  a  smooth,  very  plastic  mass 
which  shrunk  10$  in  drying  and  7$  in  burning,  giving  a  total  shrinkage 
of  life  The  air-dried  briquettes  of  this  clay  had  an  average  tensile 
strength  of  157  lbs.  per  square  inch  and  a  maximum  of  1S6  lbs. 

Incipient  fusion  occurs  at  1900°  F.,  vitrification  at  2100°  F.,  and 
viscosity  at  2300°  F. 

The  clay  burns  to  a  dark  red  body. 

This  clay  is  not  as  plastic  as  that  obtained  northwest  of  Blackburn, 
nor  is  its  tensile  strength  always  so  great,  as  will  be  seen  from  the  tests 
of  the  next  sample,  but  it  is  a  good  material  for  common  stoneware. 

The  analysis  of  the  clay  is  as  follows : 

Analysis  of  Pottery  Clay  {No.  61),  T.  Rhodes'  land,  2  miles  N.  W.  of  Lincolnton. 

Moisture 2.10 

Silica    (total)    57.20 

Alumina     24.82 

Ferric   oxide    3.25 

Ferrous  oxide 1.42 

Lime    73 

Magnesia   13 

Alkalies    93 

Water  (loss  on  ignition)    8.25 

Total   98.83 

Clay  substance   02.27 

Free  sand  36.57 

Total  fluxes  0.40 

Specific  gravity    2.51 

Sample  ~No.  49  from  the  pits  on  T.  Rhodes'  property  is  finely  gritty 
clay  which  slakes  slowly  but  completely.  It  required  the  addition  of 
40$  of  water  to  make  a  workable  paste,  which  was  very  plastic  to  the 
feel.  This  paste  shrunk  9.5$  in  drying  and  5.5$  in  burning,  giving  a 
total  shrinkage  of  15$.  The  air-dried  briquettes  made  from  tlii-  mud 
had  an  average  tensile  strength  of  133  lbs.  per  square  inch  and  a  max- 
imum of  158  lbs. 


78  CLAY    DEPOSITS    IX    XOBTH    CAEOLIXA. 

Incipient  fusion  occurred  at  1900°  F.,  vitrification  at  2100°  F.,  and 
viscosity  at  2300°  F. 

The  clay  burns  reddish  white  at  1900°  F.  and  deep  red  at  2100°  F. 
The  composition  of  it  is  as  follows : 

Analysis  of  Pottery  Clay  {No.  49),  Rhodes'  land,  2£  miles  N.  W.  of  Lincolnton. 

Moisture    69 

Silica  (total)  57.08 

Alumina    26.11 

Ferric  oxide 4.64 

Lime    20 

Magnesia    16 

Alkalies    1.42 

Water  (loss  on  ignition)   8.52 

Total    9S.82 

Clay  substance   62.76 

Free  sand  35.96 

Total    fluxes    6.42 

Specific  gravity    2.53 

POTTERY    INDUSTRY    IX    WILKES    COUNTY. 

Near  vYilkesboeo. — At  the  west  end  of  the  village  of  Wilkesboro  a 
small  pottery  has  used  the  clay  outcropping  at  the  fork  of  the  roads, 
and  also  drawn  upon  an  additional  bed  in  a  field  to  the  north. 

That  dug  along  the  road  is  a  light  bluish-white  clav.  tough,  and  con- 
taining small  amounts  of  fine  grit.  This  is  used  to  furnish  stiffness  to 
the  potter's  mixture,  while  that  from  the  field  across  the  road  furnishes  a 
bond  in  burning. 

The  stiff  clay  (Xo.  34)  is  fine-grained  and  contains  little  mica.  It 
slaked  slowly  and  required  the  addition  of  40$  of  water  to  make  a  work- 
able paste,  which  was  slightly  plastic.  This  shrunk  7.5$  in  dry- 
ing and  12$  in  burning,  giving  a  total  shrinkage  of  19.5$.  The  air- 
dried  briquettes  had  an  average  tensile  strength  of  51  lbs.  per  square 
inch  and  a  maximum  tensile  strength  of  63  lbs.  per  square  inch. 

Incipient  fusion  occurred  at  1900°  F.,  vitrification  at  2050°  F.,  and 
viscosity  at  2200°  F.  The  clay  burns  red  and  dense.  Its  composition 
is  as  follows: 

Analysis  of  Pottery  Clay  {No.  34),  near  Wilkesboro. 

Moisture    1.28 

Silica  (total)    54.38 

Alumina    27.27 

Ferric  oxide 5.48 

Lime    45 

Magnesia    41 


POTTERY    CLAYS    IN    NORTH    CAROLINA.  79 

Alkalies    68 

Water  (loss  on  ignition) 9.78 

Total    99.73 

Clay  substance   75.73 

Free  sand  24.00 

Total  fluxes  7.02 

Specific  gravity    2.37 

To  the  north  of  this  locality  one-half  mile  and  underlying  the  broad, 
low  river  terrace  along  the  Yadkin  river,  is  a  large  deposit  of  clay  on 
the  land  of  Calvin  Cowles.  A  deep  trench  has  been  run  across  the 
property,  exposing  the  clay  throughout  its  length,  and  samples  were 
taken  from  this  point. 

It  is  a  fine-grained,  smooth,  dark-colored  clay,  containing  very  little 
grit.  It  slakes  slowly  to  grains  and  granules.  35 $  of  water  were 
required  to  give  a  workable  mixture,  which  was  very  plastic.  This 
paste  shrunk  10$  in  drying  and  5$  in  burning,  giving  a  total  shrinkage 
of  15$.  The  air-dried  briquettes  had  an  average  tensile  strength  of  169 
lbs,  per  square  inch,  and  the  maximum  tensile  strength  amounted  to 
192  lbs.  per  square  inch.  Incipient  fusion  occurred  at  1800°  F.,  vitri- 
fication at  2000°  F.,  and  viscosity  at  2200°  F. 

The  clay  burns  to  a  hard,  dense,  brownish-gray  impervious  body  at 
2000°  F.,  and  should  make  an  excellent  potter's  clay.  It  required  slow 
drying  and  heating  to  avoid  cracking.  The  composition  of  it  is  as 
follows : 

Analysis  of  Pottery  Clay  {No.  35),  ]/2  mile  north  of  Wilkesooro,  C.  Cowles'  land. 

Moisture    2.20 

Silica  (total)   54.24 

Alumina    24.97 

Ferric  oxide 4.83 

Lime    57 

Magnesia    70 

Alkalies    2.52 

Water  (loss  on  ignition) 9.-40 

Total 99.43 

Clay  substance    67.0S 

Free  sand  32.35 

Total  fluxes   8.62 

Specific  gravity  2.-40 

This  is  not  unlike  the  clay  at  the  pottery,  but  its  finer  grain,  greater 
percentage  of  alkalies,  make  it  burn  dense  at  a  lower  heat. 


CHAPTER  VII. 

FIRE-CLAYS  AND  PIPE-CLAYS  IN  NORTH  CAROLINA. 

FIRE-CLAYS. 

The  fire-clay  deposits  of  North  Carolina  are  few  in  number  as  thus 
far  known.  They  are  either  residual  deposits  or  the  wash  from  them. 
There  are  a  number  of  siliceous  clays  in  the  State  which  at  a  moderate 
temperature  burn  to  a  cream-white  or  white  color,  and  the  bricks  made 
from  these  clays  are  used  for  bakers'  ovens  and  boiler  foundations. 
They  are  called  fire-brick,  but  are  not  such  in  the  true  sense  of  the  word. 

Refractory  clays  occur  at  Pomona,  Guilford  county,  and  Grover, 
Cleveland  county,  and  are  mined  at  both  places. 

While  it  is  desirable  that  fire-clays  should  possess  good  plasticity  and 
low  shrinkage,  the  main  point  is  the  refractory  character.  A  good 
fire-clay  should  be  unaffected  by  2500°  F.,  but  many  good  clays  will 
not  stand  this  degree  of  heat,  nor  is  it  required  for  the  uses  to  which 
they  are  to  be  put.  In  general,  it  may  be  said  that  the  fusible  impuri- 
ties of  a  fire-clay  should  not  exceed  3J  or  4  per  cent,  if  it  is  fine-grained, 
or  even  less  if  it  is  very  fine-grained,  but  if  coarse-grained  they  may 
reach  even  5$.  The  clay  on  the  railroad  near  Spout  Springs,  for 
example,  has  only  3.81$  of  total  fluxes,  yet  on  account  of  its  very  fine 
grain  it  is  by  no  means  refractory.  If  a  fire-clay  shrinks  too  much  in 
burning  this  may  be  often  counteracted  by  the  addition  of  "grog," 
viz.,  sand,  ground  fire-brick  or  other  substances  which  would  dilute  the 
shrinkage.  Fire-clays  which  are  fat  and  plastic  generally  burn  to  a 
dense  body,  but  crack  considerably  owing  to  their  high  shrinkage. 
This  may  be  counteracted  best  by  mixing  burned  clay  of  the  same  or 
some  other  kind  with  the  fresh  material.  This  burned  clay  or  grog, 
should  be  burned  as  dense  as  possible  before  use.  Fine-grained  or  pow- 
dered grog  permits  the  brick  to  shrink  more  in  burning  than  coarse- 
grained, and  bricks  with  the  latter  generally  stand  changes  of  tem- 
perature better.  Next  to  burned  clay,  quartz  is  the  most  important 
grog. 

If  a  fire-brick  made  only  of  clay  and  clay-grog  still  shrinks  when 
placed  in  the  furnace,  sharp  quartz  grains  should  be  added,  as  they  have 
a  tendency  to  expand  on  repeated  heatings.  Fine-grained  quartz  sand 
should  in  no  case  be  added  as  it  tends  to  act  as  a  flux  in  burning.  The 
addition  of  coarse  quartz  must  also  be  within  limits,  for  if  too  large  it 
loosens  the  stone  by  expansion. 


FIRE-CLAYS    AND    PIPE-CLAYS    IN    NORTH    CAROLINA.  81 

A  good  fire-brick  is  sometimes  made  by  mixing  a  non-plastic  refrac- 
tory clay  with  a  very  plastic,  dense  burning  semi-refractory  one. 

Fire-brick  are  now  mostly  molded  by  hand  and  repressed.  For  a 
time  many  manufacturers  molded  their  bricks  in  stiff  mud  or  even  dry- 
press  machines,  but  most  of  them  have  returned  to  the  old  method. 

FIRE-CLAYS    IN    CLEVELAND    COUNTY. 

Near  Grover. — Surrounding  the  village  of  Grover  is  an  extensive 
series  of  outcrops  of  a  light  bluish-gray  sandy  clay  of  variable  depth 
and  nature.  In  some  pits  it  shows  its  residual  character  beyond  a 
doubt,  but  at  other  points,  if  of  residual  origin,  it  appears  to  have 
been  sorted  over  and  compacted  by  water  action.  Two  companies  have 
mined  this  clay,  the  Grover  Brick  Company  and  the  Powhatan  Clay 
Manufacturing  Company  of  Richmond,  Ya. 

The  former  company  has  one  pit  in  a  hollow  along  a  stream  three 
quarters  of  a  mile  due  S.  W.  of  Grover  station.  The  upper  three  feet 
are  loam  with  lumps  of  red  clay,  and  under  this  come  6  feet  of  bluish- 
white  sandy  clay  (No.  43).  The  Grover  Brick  Company  make  their 
white  fire-brick  from  this. 

A  sample  of  this  (No.  43)  shows  it  to  be  a  gritty,  fine  to  coarse, 
dense,  tough  clay,  with  abundant  coarse  quartz  grains.  It  slakes  slowly 
to  irregular  grains  and  scales. 

The  addition  of  32^  of  water  gave  a  workable  mass  of  moderate  plas- 
ticity. This  paste  shrunk  10.6^  in  drying  and  6r/e  in  burning,  giving  a 
total  shrinkage  of  16.6^.  The  average  tensile  strength  of  the  air-dried 
briquettes  was  38  lbs.  per  square  inch  with  a  maximum  of  42  lbs. 

Incipient  fusion  occurs  at  2100°  F.,  vitrification  at  2300°  F.,  and  vis- 
cosity at  2500°  F.  The  clay  burns  white  at  incipient  fusion,  but  light 
buff  at  higher  temperature. 

The  white-burned  brick  made  from  this  clay  are  sold  as  fire-brick. 
The  composition  of  the  clay  is  as  follows: 

Analysis  of  Fire-clay  {No.  43),  Grover  Brick  Co.'s  Eskridge  pit. 

Moisture    ^6 

Silica   (total)    (^--S 

Alumina     1 8.83 

Titanium  oxide   -' 

Ferric  oxide    2.60 

Lime    "° 

Magnesia    13 

Alkalies     2.29 

Water  (loss  on  ignition)    6.47 

Total    100.33 

6 


82  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Clay  substance    46.99 

Free  sand   53.30 

Total  fluxes   5.72 

Specific  gravity    2.57 

About  500  feet  IS".  E.  of  the  preceding  is  a  second  pit  belonging  to 
the  Powhatan  Clay  Manufacturing  Company  of  Richmond,  Va.  It 
is  seven  feet  deep.  They  encountered  the  same  bluish-white  sandy 
clay,  and  at  the  bottom  of  the  excavation  found  considerable  dense, 
fine-grained  plastic  clay. 

The  bottom  clay  (No.  44)  which  they  mine  was  sampled  and  tested 
in  order  to  determine  its  difference  from  the  more  sandy  and  commoner 
clay.  It  is  a  very  plastic  clay  and  freer  from  grit  than  the  other.  It 
slakes  slowly  and  required  the  addition  of  28^  of  water  to  give  a  work- 
able mud,  which  shrunk  8$  in  drying  and  5$  in  burning,  giving  a  total 
shrinkage  of  13//.  The  average  tensile  strength  of  the  air-dried  bri- 
quettes was  39  lbs.  per  square  inch  with  a  maximum  of  45  lbs. 

Incipient  fusion  occurs  at  2100°  F.,  vitrification  at  2300°  T.,  and  vis- 
cosity at  2600°  F.     The  clay  burns  to  a  yellowish-white  body. 

The  analysis  of  the  clay  yielded  as  follows: 

Analysis  of  Fire-clay  (No.  44),  Powhatan  Clay  Mfg.  Co.,  S.  W.  of  Grover. 

Moisture    1.29 

Silica    (total)    53.07 

Alumina    29.54 

Ferric  oxide    1.27 

Ferrous  oxide   1.00 

Lime     0.15 

Magnesia    0.14 

Soda 0.S7 

Potash     1.28 

Water  (loss  on  ignition) 9.93 

Total    98.54 

Clay  substance   61.99 

Free  sand   36.55 

Total  fluxes    4.71 

Specific  gravity    2.24 

The  bricks  made  from  this  clay  have  the  reputation  of  being  free  from 
discoloration.  This  is  due  partly  to  the  low  iron  percentage,  and  partly 
to  the  fact  that  they  are  burned  hard  enough  to  oxidize  the  ferrous  iron 
and  prevent  its  being  brought  to  the  surface  of  the  brick  afterwards  in 
solution  and  oxidized  there  to  ferric  oxide. 

The  brick  have  had  an  extended  use  in  many  of  the  eastern  cities. 

The  clay  (No.  45)  in  the  other  pit  of  the  Powhatan  Clay  Manufac- 
turing Company,   one-half  mile   east  of  Grover   (see   Plate  Y,  fig.   2, 


FIRE-CLAYS    AND    PIPE-CLAYS    IN    NORTH    CAROLINA.  83 

p.  59),  is  more  like  sample  (44)  from  the  pit  of  the  Grover  Brick 
Company. 

It  is  a  mixture  of  fine  and  coarse  white  clay  with  abundant  sand 
grains  and  much  mica.  In  water  it  slakes  very  slowly.  Thirty-one 
per  cent,  of  water  added  to  it  gave  a  workable  paste,  which  was  lean 
and  gritty  and  shrunk  4^  in  drying  and  4.5$  in  burning,  giving  a  total 
shrinkage  t  of  8.5$.  The  average  tensile  strength  of  the  air-dried  bri- 
quettes was  31  lbs.  per  square  inch  with  a  maximum  of  35  lbs.  per 
square  inch. 

Incipient  fusion  occurred  at  2150°  F.,  vitrification  at  2350°  F.,  and 
viscosity  at  2550°  F.     The  clay  burns  to  a  yellowish-white. 

Its  composition  is  shown  by  the  following  analysis : 

Analysis  of  Fire-clay  (No.  45),  Powhatan  Clay  Mfg.  Co.,   yz  mile  E.  of  Grover. 

Moisture    95 

Silica  (total) 64.13 

Alumina    22.35 

Ferric  oxide 1.95 

Lime   10 

Magnesia   22 

Alkaliesi  Soda    " 

(  Potash    1.81 

Water  (loss  on  ignition)    5.98 

Total    98.48 

Clay  substance  46.88 

Free  sand  51.60 

Fluxes 5.07 

Specific  gravity 2.51 

There  are  two  more  openings  in  the  same  deposit  a  short  distance 
south  of  Grover.  These  clays  around  Grover  are  all  good  semi-refrac- 
tory clays,  and  they  make  an  excellent  yellowish- white  brick;  but  their 
chief  use  up  to  the  present  time  has  been  for  the  manufacture  of  light 
brick.     These  are  molded  on  stiff-mud.  auger  machines  and  repressed. 

The  pit  from  which  the  residual  clay  iSTo.  45  came  is  shown  in  fig.  2. 

FIRE-CLAYS    IN    GUILFORD    COUNTY. 

Pomona  Clay  Bank. — The  Pomona  Terracotta  Company  has  a 
deposit  of  white,  very  sandy,  coarse-grained  clay  on  its  property  which 
is  used  for  the  manufacture  of  fire-brick.  Judging  from  the  angular 
grains  in  its  substance,  as  well  as  the  abundance  of  prominent  mica 
scales,  it  is  probably  a  residual  deposit  which  has  been  somewhat  altered 
by  wash.     It  occurs  on  the  south  side  of  Xorth  Buffalo  creek  and  just 


84  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

east  of  the  company's  new  factory.  The  available  portion  of  it  is  three 
feet  thick,  for  it  then  changes  into  a  very  sandy  clay  which  possesses 
exceedingly  low  plasticity.  The  upper  clay  slakes  very  slowly  to  a 
granular,  gritty  mass.  It  required  26$  of  water  to  make  a  workable 
paste  out  of  it,  and  this  was  lean.  This  paste  shrunk  10$  in  drying  and 
2$  additional  in  burning,  giving  a  total  shrinkage  of  12$.  Air-dried 
briquettes  made  from  this  paste  had  an  average  tensile  strength  of  -17 
lbs.  per  square  inch  and  a  maximum  of  49  lbs.  per  square  inch. 

Incipient  fusion  occurs  at  2150°  F.,  vitrification  at  2350°  I\,  and  vis- 
cosity at  2550°  F. 

The  clay  burns  red  or  buff,  depending  on  the  intensity  of  firing  and 
oxidizing  condition  of  the  fire.     Its  chemical  composition  is  as  follows: 

Analysis  of  Fire-clay  {No.  25),  Pomona  Terracotta  Works. 

Moisture   9S 

Silica   (total)    70.45 

Alumina    17.34 

Ferric   oxide    3.16 

Ferrous  oxide   33 

Lime    25 

Magnesia    22 

Alkalies     70 

Water  (loss  on  ignition)   6.63 

Total    100.06 

Clay  substance   48.26 

Free  sand   51.50 

Fluxes    4.66 

Specific   gravity    2.55 

The  under  clay  (25a)  is  a  very  siliceous  white  clay  that  slakes  slowly 
and  completely  to  irregular  grains. 

Thirty-three  per  cent,  of  water  added  to  it  gave  a  workable  but  very 
lean  mass  which  shrunk  3$  in  drying  and  3$  in  burning,  giving  a  total 
shrinkage  of  6$. 

The  average  tensile  strength  of  air-dried  briquettes  was  14  lbs.  per 
square  inch  with  a  maximum  of  16  lbs.  Incipient  fusion  occurred  at 
2200°  F.,  vitrification  at  2400°  F.,  and  viscosity  at  2600°  F.  The  clay 
burns  to  a  gray  buff. 

This  clay  is  not  used.  Attempts  have  been  made  to  mix  it  with  the 
sewer-pipe  clay,  but  it  would  not  take  the  salt  glaze.  The  trouble  is 
probably  similar  to  a  case  which  Prof.  E.  Orton,  Jr.,  cited  to  the  writer 
from  Ohio,  the  difficulty  lying  in  the  extremely  siliceous  nature  of  the 
clay,  which  does  not  possess  enough  alumina  to  unite  with  the  silica 
and  salt  to  give  the  glaze,  which  is  a  silicate  of  aluminium  and  sodium. 

The  composition  of  this  under  fire  clay  is  as  follows: 


FIRE-CLAYS    AND    PIPE-CLAYS    IN    NORTH    CAROLINA.  85 

Analysis  of  Clay  (No.  25a),  under  the  Fire-clay,  Pomona  Terracotta  Works. 

Moisture    1.17 

Silica  (total)   70.15 

Alumina    15.51 

Ferric   oxide 3.34 

Lime    83 

Magnesia    07 

Alkalies    3.75 

Water  (loss  on  ignition)    5.14 

Total    09.96 

Clay  substance  39.46 

Free  sand    60.50 

Total  fluxes    7.99 

There  is  probably  much  undecomposed  feldspar  in  the  clay,  and  while 
the  total  fluxes  are  high,  the  grain  is  so  coarse  as  to  raise  the  fusing 
point. 

Woodroffe  Clay  Bank. — Tlios.  Woodroffe,  of  Greensboro,  has  a 
similar  deposit  of  fire-clay  about  one  mile  north  of  the  Pomona  sewer- 
pipe  works  and  along  the  same  creek.  It  is  likewise  a  very  gritty,  tough, 
dense,  light  gray  clay,  that  slakes  very  slowly.  Twenty-eight  per  cent, 
of  water  was  required  to  make  a  workable  mixture.  This  shrunk  9.3$ 
in  drying  and  4^  in  burning,  giving  a  total  shrinkage  of  13.3/fc.  Air- 
dried  briquettes  of  the  mud  had  an  average  tensile  strength  of  51  lbs. 
per  square  inch  and  a  maximum  of  56  lbs.  per  square  inch.  Incipient 
fusion  occurs  at  2100°  F.,  vitrification  at  2300°  F.,  and  viscosity  at 
2500°  F. 

If  burned  reddish  when  heated  to  barely  2100°  F.,  or  in  reducing  fire 
the  clay  remained  white.  This  is  the  condition  of  the  bricks  manu- 
factured from  this  fire-clay  at  Pomona,  but  if  the  clay  is  raised  above 
2100°  F.  and  with  an  oxidizing  lire  the  clay  burns  buff  or  red. 

The  composition  of  the  clay  from  WoodronVs  bank  is  shown  by  the 

following: 

Analysis  of  Fire-clay  {No.  29),  Woodroffe  Bank. 

Moisture    1.13 

Silica   (total)    71.60 

Alumina    1 5.27 

Ferric  oxide    •">••">•'> 

Lime    IT 

Magnesia    21 

Alkalies    •   -M -* 

Water  (loss  on  ignition)    5.40 

Total 99.53 

Clay  substance  42.83 

Free  sand  56.70 

Total  fluxes  5.83 

Specific  gravity   2.60 


86  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

This  closely  approaches  the  Pomona  Sewer-pipe  and  Brick  Co.'s  clay 
in  composition. 

PIPE-CLAYS   IN   NORTH    CAROLINA. 

Clays  which  are  suitable  for  the  manufacture  of  sewer-pipe  should 
answer  the  following  requirements: 

They  should  be  plastic  to  permit  molding  without  cracking;  they 
should  have  a  tensile  strength  of  125-150  lbs.  The  clay  should  burn 
to  a  dense,  hard,  impervious  body,  of  a  red  or  deep  red  color.  The  dry- 
ing should  permit  of  rapidity,  and  the  ware  should  not  warp  or  crack 
in  doing  so.     The  same  may  be  said  of  the  burning. 

An  excess  of  fluxing  impurities  may  render  a  clay  so  fusible  that  in 
burning  it  softens  to  such  an  extent  as  to  lose  its  shape.  It  is  a  very 
common  practice  therefore  to  use  a  mixture  of  clays,  the  one  fusible  to 
form  a  bond  in  burning,  the  other  much  less  so  to  preserve  the  shape 
of  the  ware.     This  is  done  at  Pomona,  for  example. 

There  should  be  a  considerable  but  not  excessive  percentage  of 
silica  in  the  clay  for  the  salt  vapors  to  unite  with  and  form  the  glaze. 
An  excess  of  silica  is  detrimental,  However,  to  the  formation  of  a  good 
glaze,  for  the  latter  is  a  silicate  of  sodium  and  aluminium,  and  conse- 
quently if  there  is  an  excess  of  silica  and  lack  of  alumina,  a  poor  glaze, 
or  perhaps  none  at  all,  may  form.  This  is  probably  the  case  with  the 
under  fire-clay  at  Pomona,  which  for  a  while  was  mixed  in  with  the 
pipe-clay. 

MANUFACTURE    OF    SEWER-PIPE    AND    TILE. 

If  shale  or  hard  clay  is  used  it  has  to  be  first  ground  in  a  dry  pan, 
but  with  soft  clays  they  can  be  put  directly  into  the  wet  pan  or  chaser 
mill,  which  in  a  few  minutes  tempers  each  charge  rapidly  and  thor- 
oughly.    (Plate  YI,  fig.  2.) 

This  method  of  tempering  is  far  more  thorough  and  quicker  than  a 
pugmill,  although  requiring  more  power. 

The  tempered  clay  is  generally  taken  to  the  upper  story  of  the  fac- 
tory by  means  of  bucket  elevators  and  discharged  into  the  clay  cylinder 
of  the  sewer-pipe  press.     (Pig.  3,  p.  87,  and  Plate  VI,  fig.  1.) 

The  press  (fig.  3,  page  87)  consists  of  two  cylinders,  an  upper  steam 
and  a  lower  clay  cylinder,  and  the  ratio  of  their  diameters  is  generally 
as  3  :  1.  The  clay  cylinder  is  filled  with  clay,  and  the  piston  then  forced 
downwards  by  the  piston  of  the  steam  cylinder  above,  the  piston  rod 
of  the  two  being  continuous.  This  forces  the  clay  out  through  the  die 
at  the  bottom.  When  the  clay  in  the  form  of  a  pipe  has  issued  to  the 
proper  distance,  the  machine  is  stopped.  If  of  small  diameter  the  pipe 
is  sometimes  simply  broken  off,  but  for  large  pipe  and  usually  small 
ones  the  pipe  is  cut  off  close  to  the  mouth  of  the  die  either  by  means 
of  a  wire  or  else  by  an  automatic  knife  edge  located  within  the  die. 


N.  C.  GEOLOGICAL  SURVEY 


BULLETIN  13,  PLATE  VI. 


FIG.    1.— PRESS   FOR   SEWER-PIPE,  TILE,   AND   HOLLOW   BRICK. 


FIG.   2— CHASER    MILL    FOR   TEMPERING   CLAY    FOR   SEWER-PIPE. 


Yig.  3.—  Vaughn  Sewer-Pife  Press,  No.  7. 
60  inch  Steam  Cylinder,  36  inch  clay  Cylinder. 


88  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

The  edges  of  the  pipe  are  trimmed  and  the  pipe  are  then  set  on  the 
drying  floor. 

Small  diameter  pipe  can  be  dried  comparatively  fast,  but  large  ones 
must  be  dried  very  slowly. 

Sewer-pipe  are  usually  burned  in  circular  kilns  of  down-draft  pat- 
tern, which  are  from  16-25  ft.  (rarely  more)  in  diameter.  The  pipes 
are  set  on  top  of  each  other,  and  when  there  are  several  sizes  they  are 
nested.     Figure  1  of  Plate  VII  shows  a  circular  down-draft  kiln. 

The  burning  can  proceed  quite  rapidly  on  account  of  the  thinness 
of  the  ware.  The  salt  is  added  to  the  fires  when  the  temperature  of 
the  kiln  has  reached  its  maximum. 

Sewer-pipe  should  be  free  from  blister,  cracks  and  other  defects. 
They  should  also  be  straight. 

Elbows  and  Y's  are  made  by  molding  the  clay  in  plaster  molds,  or 
in  the  case  of  Y's  and  T's  straight  pieces  of  pipe  are  sometimes  trim- 
med to  fit  together  in  the  desired  shape,  and  the  parts  cemented  by  slip. 
They  have  to  be  dried  more  slowly.  Sewer-pipe  are  made  from  2  to 
2-J  ft.  in  length,  and  in  diameter  from  3-30  inches. 

GUILFORD    COUNTY. 

Pomona  Terracotta  Co.'s  Works. — The  Pomona  Terracotta  Com- 
pany has  its  works  and  clay  pits  at  Pomona,  three  miles  west  of  Greens- 
boro. The  clays- occur  in  the  bottom  of  the  flat  valley  along  both  sides  of 
North  Buffalo  creek,  and  are  practically  of  two  kinds,  a  plastic  pipe- 
clay, and  a  white  quartzose  clay,  called  a  fire-clay.  The  pipe-clay  is 
said  to  occur  only  on  the  north  side  of  the  creek  and  the  fire-clay  on 
the  south  side.  This  is  true  for  the  sewer-pipe  company's  pits,  and  they 
also  claim  it  to  hold  true  at  other  points  above  and  below  them  on  the 
creek.  There  are  four  pits  opened  up  in  the  pipe-clay.  In  the  first, 
or  that  nearest  to  the  factory,  there  are  five  feet  of  dark  clay,  and  two 
feet  of  red.  The  material  from  this  pit  furnishes  one-half  of  the  sewer- 
pipe  mixture.  That  in  the  second  pit  is  similar  to  the  lower  clay  in  the 
first,  but  is  said  to  shrink  less  in  burning. 

The  upper  red  in  the  first  pit  (No.  27)  is  a  lean,  gritty  clay,  which 
required  the  addition  of  30$  of  water  to  make  a  workable  paste.  In 
water  the  clay  slakes  quickly  to  scaly  fragments.  The  clay  shrinks 
10$  in  drying  and  6$  in  burning,  giving  a  total  shrinkage  of  16$.  The 
average  tensile  strength  of  the  air-dried  briquettes  was  59  lbs.  per 
square  inch,  with  a  maximum  of  67  lbs.  per  square  inch.  Incipient 
fusion  occurs  at  2000°  F.,  vitrification  at  2150°  F.,  and  viscosity  at 
2300°  F.  The  clay  burns  to  a  brownish  red.  Its  composition  is  as  fol- 
lows : 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  13,  PLATE  VII. 


£^ 


FIG.    1.— CIRCULAR    DOWN-DRAFT   KILN    FOR   TILE,    &c. 


5™                                                                               v. 

jtJ$MLl 

lUi  I  1  m\  1 

W^^^^^^: 

KB^^^^^^-1"        *^ 

FiQ.   2.— TUNNE.    DRYERS     USED   IN    BRICK   MAKING. 
(See  page  98.) 


..1 


FIRE-CLAYS    AND    PIPE-CLAYS    IN    NOETH    CAROLINA.  81) 

Analysis  of  upper  Pipe-clay  {No.  21),  Pomona  Terracotta  Co. 

Moisture     2.05 

Silica  (total)    54.28 

Alumina    22.27 

Ferric  oxide 8.45 

Ferrous  oxide   1.33 

Lime    45 

Magnesia    18 

Alkalies    60 

Water  (loss  on  ignition)    10.50 

Total    100.11 

Clay   substance    67.57 

Free   sand    32.51 

Fluxes     11.01 

Specific  gravity    2.50 

The  color  of  the  fresh  clay  is  evidently  due  to  the  high  amount  of 
hydrated  ferric  oxide  or  limonite. 

The  under  clay  (No.  26)  from  this  same  pit  is  also  a  gritty  clay,  but 
more  plastic.  It  slakes  slowly  to  scaly  fragments.  Forty  per  cent,  of 
water  was  required  to  make  a  workable  mass,  which  shrunk  10$  in 
drying  and  6$  in  burning,  giving  a  total  shrinkage  of  lQfc  The  air- 
dried  briquettes  made  from  this  material  had  an  average  tensile  strength 
of  86  lbs.  per  square  inch  and  a  maximum  of  103  lbs.  Incipient  fusion 
occurred  at  2050°  F.,  vitrification  at  2250°  F.?  and  viscosity  at  2150°  F. 

The  clay  burns  red.  Its  composition  is  shown  by  the  following 
analysis : 

Analysis  of  under  Pipe-clay  {No.  26),  Pomona  Terracotta  Co. 

Moisture    1.53 

Silica  (total)    58.73 

Alumina    23.94 

Ferric  oxide    3.71 

Lime    05 

Magnesia    09 

Alkalies     1.25 

Water  (loss  on  ignition)  9.S0 

Total 99.10 

Clay    substance    65.70 

Free  sand   •*>•">.  I" 

Fluxes    5.1  ( > 

Specific   gravity    2.52 

The  clay  in  the  second  pit  (No.  28)  is  a  gray,  gritty  clay  with  numer- 
ous quartz  grains,  tough,  moderately  fine-grained,  ami  -lake-  slowl; 
irregular  granules. 


v    to 


90  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

It  required  the  addition  of  33^  of  water  to  produce  a  workable  mass, 
which,  however,  was  quite  plastic,  but  did  not  feel  as  plastic  as  the 
tensile  strength  would  suggest  it  to  be.  This  mixture  shrunk  8$  in  dry- 
ing and  2>c/c  in  burning.  The  average  tensile  strength  of  the  air-dried 
briquettes  was  145  lbs.  per  square  inch,  with  a  maximum  of  160  lbs. 
per  square  inch.  Incipient  fusion  occurred  at  2000°  F.,  vitrification  at 
2200°  F.,  and  viscosity  at  2400°  F. 

The  clay  analyzed  as  follows : 

Analysis  of  Pipe-clay  {No.  28),  2nd  pit  Pomona  Terracotta  Go. 

Moisture   2.20 

Silica  (total)    70.75 

Alumina    13.87 

Ferric  oxide    5.01 

Lime    82 

Magnesia    29 

Alkalies    1.15 

Water  (loss  on  ignition)  5.00 

Total    99.09 

Clay  substance  39.40 

Free  sand    59.70 

Fluxes     7.27 

Specific  gravity    2.51 

As  these  three  clays  serve  different  purposes  in  the  manufacture  of 
the  sewer-pipe,  it  may  be  well  to  compare  them. 

No.  26.     Good  plasticity. 

No.  27.  Gives  a  better  red  in  burning,  and  vitrifies  at  lower  tem- 
perature. 

^N"o.  28.  Shrinks  less  and  has  better  bonding  qualities.  The  char- 
acters are  summed  up  in  the  following  table : 

Comparison  of  Pipe-clays,  Pomona  Terracotta  Co. 
No.  of 

the  Tensile  Temperature  in  F.  Degrees. 

Sam-  Shrinkage.  Strength.  Incipient       Vitri-  Viscos- 

ple.  Feel.        Drying.   Burning.    Av.         Max.       Fluxes.        Fusion,      fication.  ity. 

26  Plastic  10$  6$  86  103  5.10$  2050°         2250°  2150° 

27  Lean  10$  6$  59  67         11.07$         2000°         2150°  2300° 

28  Very  plastic       8$  3$  145         160  7.27$         2000°  2200°  2400° 

The  clay  as  it  is  mined  is  thrown  into  cars  which  are  run  to  the  foot 
of  an  incline  up  which  they  are  drawn  by  a  cable  to  the  factory.  The 
clay  mixture  is  put  through  the  usual  chaser  mill,  each  charge  being 
tempered  about  four  minutes.  It  is  then  carried  on  an  endless  belt  to 
the  pipe  press.  In  their  old  building  the  company  has  Barber  sewer- 
pipe  presses,  and  Penfield  presses  in  the  new  works.     There  are  several 


FIRE-CLAYS    AND    PIPE-CLAYS    IN    NORTH    CAROLINA.  91 

stories  of  slatted  drying  floors  in  each  of  the  two  factories,  and  the  heat 
is  supplied  by  coils  of  pipe  on  the  lower  floor.  The  diameters  of  sewer- 
pipe  made  are  the  usual  ones  up  to  24  inches  in  diameter,  inside  measure. 
A  second  grade  of  sewer-pipe  of  the  same  sizes,  manufactured  here,  is 
now  used  largely  as  a  substitute  for  stone  culverts  at  public  road  cross- 
ings. And  in  addition  to  these  the  company  manufactures  the  follow- 
ing: Terracotta  well  tubing,  10  to  24  inches  inside  diameter,  and  2  feet 
long;  terracotta  chimney  flues;  and  farm  drain  tile  2^  to  12  inches  in 
diameter. 

The  burning  is  done  in  circular  down-draft  kilns,  26  ft.  in  diameter 
and  8i  ft.  high,  with  inclined  grate  bars  in  the  fire-places.  Soft  clinker 
coal  is  used  for  fuel.  There  are  12  kilns  altogether,  with  one  stack 
for  two  kilns.  (See  Plate  I,  frontispiece,  for  a  general  view  of  the 
works.) 

Flue  linings  and  semi-fire-brick  are  also  made  and  burned  in  the  same 
kilns. 

The  company  has  an  abundance  of  available  clay,  as  it  controls  much 
land  bordering  the  North  Buffalo  creek  and  has  exploited  the  clay 
b^ds  to  a  considerable  extent.  It  has  a  complete  modern  plant,  having 
recently  more  than  doubled  its  capacity,  and  is  turning  out  some  excel- 
lent material. 


CHAPTER  VIII. 
,     BRICK-CLAYS  AND  BRICK  MANUFACTURE. 

GENERAL  CHARACTER  OF  BRICK-CLAYS. 

Clays  suitable  for  the  manufacture  of  common  brick  are  so  widely 
distributed  in  North  Carolina  that  it  is  hardly  necessary  to  say  more 
here  than  to  refer  to  the  detailed  descriptions  of  the  more  important 
occurrences. 

In  North  Carolina  two  kinds  of  clay  are  used: 

1.  Residual  clays. 

2.  Sedimentary  clays. 

The  residual  clays  are  to  be  found  all  over  the  Piedmont  plateau  and 
mountain  regions  of  the  state,  and  their  thickness  depends  on  the  depth 
to  which  the  rocks  have  disintegrated,  and  also  on  the  slope  of  the  land, 
for  on  steep  slopes  the  material  is  rapidly  washed  away.  Residual  clays 
are  usually  impure.  Those  around  Greensboro,  which  are  the  most 
worked,  showed  from  8-12$  total  fluxes.  Owing  to  the  high  percentage 
of  undecomposed  mineral  matter  in  some  of  them,  they  are  generally 
gritty,  sandy,  and  possess  little  plasticity.  They  frequently  absorb  a 
large  amount  of  water  in  molding,  which  they  have  to  give  off  again  in 
drying,  with  the  consequent  danger  of  checking;  this  is  especially  apt  to 
happen  when  the  soft-mud  process  of  hand-molding  is  used.  Owing  to 
their  coarseness  of  grain  the  residuals  do  not  fuse  incipiently  under 
2000°-2100°  F.,  while  the  sedimentary  clays  generally  reach  the  same 
condition  at  1900°  F.  As  very  few  of  the  smaller  brickmakers  reach 
a  temperature  of  over  1950°  F.  in  burning,  the  brick  are  generally 
underburned,  porous  and  weak. 

It  has  been  noticed  that  when  these  clays  are  molded  in  a  steam- 
power  machine,  especially  a  stiff-mud  machine,  which  requires  less  water 
to  be  added  to  the  paste,  the  resulting  brick  is  smoother  and  denser. 
Having  less  water,  it  shrinks  less  in  drying,  and  consequently  there  is 
less  danger  of  cracking.  The  use  of  some  permanent  form  of  kiln  also 
gives  better  results,  as  the  heat  can  be  better  regulated. 

The  sedimentary  clays  are  found  unde^Jying  terraces  along  the  rivers 
or  else  in  the  valley  bottoms,  where  the}  represent  the  accumulation 
of  clay  sediments  in  lakes  or  ponds.  These  clays  are  far  preferable 
to  the  residual  ones,  for  they  burn  dense  at  a  lower  temperature;  they 
are  more  plastic,  smoother,  have  greater  tensile  strength,  and  generally 
burn  to  a  better  color  than  the  residual  clays. 


J 


BRICK-CLAYS    AND    BRICK    MANUFACTURE.  93 

REQUISITES  OF  BRICK-CLAYS. 

The  more  impure  clays  are  generally  used  for  the  manufacture  of 
building  brick.  They  should  burn  to  a  good  red  color,  preferably  at  a 
temperature  not  greater  than  2000°  F.  or  2100°  F.  They  should  have 
enough  fluxes  to  cement  the  particles  to  a  hard  and  dense  body  at  the 
above  temperature.  From  5-7$  of  iron  is  desirable,  as  this  amount  has 
generally  been  found  to  exert  the  best  coloring  action.  A  large  amount 
of  lime  is  undesirable,  for  it  brings  the  temperatures  of  fusion  and 
incipient  vitrification  too  close  together,  although  Seger  has  shown  that 
with  care  a  good  brick  may  be  made  from  a  clay  containing  20-25$  of 
calcium  carbonate.  Its  tendency,  as  previously  stated  (chemical  prop- 
erties of  clays),  is  to  lessen  the  shrinkage.  If  brick-clays  contain  lime, 
it  should  be  finely  and  evenly  disseminated,  for  if  in  lumps,  these  are 
apt  to  split  the  burned  brick  (see  p.  21). 

Sand  seems  generally  to  decrease  the  plasticity  and  tensile  strength, 
whether  present  in  coarse  grains  as  in  the  laminated  black  clay  on  the 
Cape  Fear  river  at  Prospect  Hall,  or  in  a  finely  divided  condition  as  in 
the  kaolin  four  miles  west  of  Troy.  It  also  diminishes  the  shrinkage  to 
a  A^ariable  extent.  Indeed,  sand  is  sometimes  added  to  very  plastic 
clays  to  facilitate  molding  and  decrease  the  shrinkage  in  drying  and 
burning.  It  should  be  borne  in  mind,  however,  that  it  is  harmful  to 
go  to  the  other  extreme  and  add  too  much  sand,  for  the  tendency  is  to 
produce  a  weak,  porous  brick,  especially  if  hand-molded. 

Fine-grained  clays  and  very  plastic  ones  generally  require  slow  dry- 
ing. The  reason  for  this  is  that  on  account  of  the  smallness  of  the  pores 
the  moisture  cannot  escape  so  readily,  and  the  outer  portion  of  the 
brick  dries  and  shrinks  quicker  than  the  interior.  The  result  is  crack- 
ing. Kapid  drying  may  be  prevented  somewhat  by  adding  salt  water 
to  the  clay;  this  is  a  common  practice  in  portions  of  Missouri.1 

Fine-grained  clays  very  often  have  to  be  heated  slowly  in  the  early 
stages  of  burning,  although  in  the  case  of  fine-grained  clays  with  an 
abundance  of  fine  sand  they  can  generally  be  heated  rapidly,  so  far  as 
the  North  Carolina  clays  are  concerned. 

The  range  of  the  various  constituents  in  the  North  Carolina  brick- 
clays  is  as  follows : 

Range  of  Constituents  in  North  Carolina  Brick-Clays. 

Range.  Average. 

Silica * 52-70  G0.00 

Alumina 13-2S  18.00 

Ferric  oxide   | 1.5-11.5  6.00 

Lime    ?* 0.10-2.5  O.fiO 

Magnesia    0.10-1.5  0.40 


Alkalies 

0.20-4.5 

2.00 

Water    

4-12 

7.00 

Total   fluxes 

3.5-17.5 

1  Mo.  Geol.  Survey,  XI,  p.  481. 

9.00 

'94  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

This  is  about  the  usual  composition  of  brick  clays,  with  the  exception 
of  lime  and  magnesia,  which  are  somewhat  low. 

METHODS    OF    BRICK   MANUFACTURE. 

All  clay  when  made  into  building  brick  has  to  go  through  the  fol- 
lowing stages : 

1.  Preparation  (crushing  or  tempering,  or  both). 

2.  Molding. 

3.  Drying. 

4.  Burning. 

Various  methods  may  be  used  in  each  stage  of  the  manufacture,  and 
this  is  especially  the  case  in  molding,  and,  therefore,  four  methods  of 
manufacture  are  generally  recognized,  according  to  the  type  of  machine 
used  to  shape  the  clay.     These  four  processes  are: 

1.  Soft-mud. 

2.  Stiff-mud. 

3.  Semi-dry  press. 

4.  Dry  press. 

Each  of  these  processes  has  certain  advantages,  and  its  applicability 
depends  on  the  character  of  the  clay,  capacity  desired,  and  capital  avail- 
able. 

SOFT-MUD    PROCESS. 

In  North  Carolina  this  is  the  one  most  generally  used.  It  is  adapt- 
able to  almost  any  clay,  and  requires  the  least  amount  of  capital. 

Tempering-  the  Clay. — The  clays  used  are  generally  soft  ones,  such 
as  require  no  grinding.  They  are  first  tempered  with  water.  This  is 
done  either  by  throwing  the  clay  into  a  large  rectangular  pit  behind 
the  molding  machine,  pouring  water  over  it  and  allowing  it  to  soak,  or 
else  tempering  it  in  ring-pits.  These  consist  of  circular  pits  15-20  feet 
in  diameter  and  2-3  feet  deep.  In  each  pit  there  revolves  a  large  iron 
wheel  attached  to  a  post  in  the  centre,  and  so  geared  that  it  travels 
back  and  forth  from  the  centre  to  the  circumference  of  the  pit  as  it 
travels  around.  The  clay  is  shoveled  into  the  pit,  water  poured  over  it 
and  the  mass  allowed  to  soak  for  12  hours,  and  it  is  then  mixed  by  the 
wheel  for  about  six  hours  more.  This  is  by  far  the  best  method  of 
tempering  clay  for  the  soft-mud  process,  for  it  mixes  the  clay  into  a 
homogeneous  mass,  which  is  something  a  soak  pit  does  not  do. 

Many  small  manufacturers  in  the  South  have  a  rather  crude  arrange- 
ment for  tempering  their  clay.  It  consists  of  a  vertical  rectangular 
box,  in  which  there  is  set  an  upright  shaft  with  cross-arms.  The  clay 
is  thrown  in  at  the  top,  and  by  the  revolution  of  the  shaft,  operated  by 
horse-power,  it  is  forced  slowly  downward  and  out  at  the  bottom. 


BRICK-CLAYS    AND    BRICK    MANUFACTURE.  95 

Pugmills  are  sometimes  used  in  connection  with  soft-mud  machines, 
but  are  more  frequently  used  in  connection  with  the  stiff-mud  process, 
and  will  be  described  under  that  head. 

Molding  the  Brick. — The  clay  is  molded  by  hand  or  in  machines 
operated  either  by  steam  or  horse-power.  When  the  clay  is  molded  by 
hand  it  is  generally  tempered  somewhat  softer,  often  too  much  so.  A 
wooden  mold  is  used.  The  molder  takes  a  chunk  of  clay  from  his 
supply  on  a  table  near  him,  and  forming  it  roughly  he  lifts  it  up  and 
then  throws  it  downward  into  the  mold,  which  has  been  previously 
sanded  on  the  inside  to  prevent  the  clay  adhering.  The  mold  is  then 
reversed  onto  a  pallet,  the  brick  drops  out  and  is  carried  off  by  a  boy, 
the  "  off-bearer,"  and  placed  on  the  yard  to  dry. 

A  man  can  mold  about  2500-3000  bricks  per  day  by  this  method. 

The  day's  work  of  molded  brick,  which  have  been  spread  out  on  the 
yard  to  dry,  are  turned  on  edge  at  the  end  of  the  day  to  permit  equal 
drying.  Sometimes  a  boy  goes  along  the  rows  of  brick  and,  with  a  flat 
board  fastened  to  the  end  of  a  stick,  stamps  the  brick  in  order  to  square 
them  up  in  case  the  clay  was  too  wet  to  hold  its  shape. 

Hand-molding  is  a  cheap  method  as  far  as  cost  of  plant  is  concerned, 
but  the  capacity  is  small.  Hand-made  bricks  are  generally  porous  and 
light,  as  the  clay  receives  little  pressure  in  molding,  but  they  are  homo- 
geneous in  structure,  and  when  hard-burnt  are  usually  strong. 

The  celebrated  Philadelphia  red  front  brick  were  for  a  long  time 
molded  by  hand  and  then  re-pressed. 

When  soft-mud  brick  are  molded  by  machine  the  clay  is  fed  into  the 
upper  end  of  a  rectangular  box,  which  is  really  a  vertical  pugmill.  The 
clay  passes  downward  and  is  forced  into  a  six-brick  mold  at  the  bottom; 
the  latter,  as  soon  as  filled,  being  thrust  out.  Such  machines  have  a 
capacity  of  about  20,000  brick  per  day.  It  requires  from  5  to  7  men  to 
operate  one  of  these  machines,  that  is,  a  shoveler,  mold-sander,  mold- 
lander,  who  receives  the  mold  and  trims  off  the  superfluous  clay,  and 
two  or  three  off-bearers  to  spread  the  brick  on  the  yard. 

Drying. — Soft-mud  bricks  are  generally  dried  in  the  sun.  As  this 
method  requires  considerable  space,  especially  when  large  capacity  is 
required,  it  is  sometimes  found  desirable  to  dry  the  brick  on  pallets 
set  one  above  the  other  on  racks.  This  increases  the  drying  capacity, 
avoids  handling  until  the  brick  are  set  in  the  kiln,  and  there  is  no  loss 
from  washed  brick.     The  drying  takes  a  little  longer. 

Burning. — Soft-mud  bricks  are  usually  burned  in  scove-kilns;  that 
is,  they  are  piled  up  in  rectangular  masses  35-iO  courses  high,  and  open 
spaces  or  arches  are  left  at  intervals  in  the  bottom  of  the  pile  these 
arches  running  through  the  mass. 

The  exterior  of  the  "  kiln  "  is  daubed  over  with  mud.  and  one  or  two 


96  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

courses  of  brick,  called  the  "  platting,"  are  laid  natside  down  on  the 
top  of  the  kiln  to  keep  the  heat  in.  Fires  are  then  built  in  both  ends 
of  the  arches,  and  the  interior  of  the  kiln  is  gradually  heated  to  the 
desired  temperature. 

Burning  is  the  most  important  step  in  the  manufacture  of  brick.  It 
is  important  that  the  heat  should  be  raised  slowly  during  water-smoking 
and  also  while  the  combined  water  is  being  driven  off,  and,  furthermore, 
that  the  temperature  should  be  distributed  as  evenly  as  possible  through- 
out the  kiln,  for  it  is  a  common  fault  at  many  of  the  smaller  yards  that 
the  arches  are  almost  melted  while  the  upper  courses  can  sometimes 
barely  be  called  salmon  brick.  In  this  connection  there  may  be  men- 
tioned the  practice  followed  by  some  manufacturers  of  adding  coal-dust 
to  the  brick  to  be  placed  in  those  parts  of  the  kiln  which  do  not  receive 
sufficient  heat.  In  burning,  the  coal-dust  in  the  brick  ignites  and  sup- 
plies additional  heat  where  it  is  needed.  The  coal  dust  is  added  in  the 
proportions  of  one  bushel  to  clay  for  1000  brick,  and  is  added  to  the 
clay  before  it  is  tempered.  Wood  is  the  fuel  commonly  used  in  burning 
soft-mud  brick.  The  arches  are  often  closed  by  iron  doors,  and  these 
should  never  be  omitted,  for  a  flood  of  cold  air  rushing  into  a  mass  of 
red-hot  brick  is  sure  to  do  damage. 

If  the  heat  is  raised  too  rapidly,  the  outer  part  of  the  brick  shrinks 
and  becomes  dense  before  the  ferrous  oxide  of  the  interior  has  been 
converted  to  the  ferric  oxide,  and  a  black  core  is  generally  to  be  seen 
in  such  cases;  unequal  shrinkage  and  consequent  cracking  also  results 
from  the  same  cause. 

STIFF-MUD    PROCESS. 

Preparation  of  the  Clay. — This  method  of  making  brick  is  appli- 
cable to  either  shales  or  clays.  In  the  case  of  the  former  they  generally 
have  to  be  prepared  by  grinding  them  in  a  dry  pan.  This  consists  of  a 
large  circular  revolving  iron  pan  about  9  feet  in  diameter  (fig.  4=, 
p.  97).  In  this  there  are  two  iron  rolls  weighing  3000-1000  pounds 
each,  and  which  revolve  by  friction  against  the  bottom  of  the  pan.  The 
outer  part  of  the  bottom  is  perforated  by  slits  one-fourteenth  to  one- 
sixteenth  inch  diameter,  according  to  the  fineness  to  which  the  material 
is  to  be  ground. 

For  softer  shales  and  tough  clays  a  disintegrator  is  used. 

Many  of  the  North  Carolina  manufacturers  pass  their  clay  first 
through  a  pair  of  rolls,  but  as  in  most  instances  where  these  are  used 
the  clay  contains  no  stones  and  needs  only  tempering,  the  advantage 
of  using  the  rolls  is  not  apparent. 

Tempering  the  Clay. — For  a  stiff-mud  machine  the  tempering  is 
generally  done  in  a  pugmill.      This  consists  of  a  horizontal  trough  ir» 


BRICK-CLAYS    AND    BRICK    MANUFACTURE. 


97 


which  there  revolves  a  shaft  bearing  knife  blades  set  at  a  small  angle. 
The  clay  and  water  are  fed  in  at  one  end  and  as  they  are  pushed  for- 
ward towards  the  other  end,  where  they  are  discharged  into  the  machine, 
they  become  thoroughly  mixed.  This  is  of  considerable  importance,  for 
in  the  case  of  laminated  clays  their  structure  should  be  destroyed  by 
thorough  mixing.  Pugmills  are  generally  six  or  eight  feet  long,  and 
the  longer  the  better.  A  wet  pan  gives  better  results  than  a  piigmill, 
for  it  not  only  crushes  a  soft  clay  but  tempers  it  thoroughly. 


Fig.  4. — Dry-Pan  Ckusher. 


There  are  many  stiff-mud  auger  machines  put  on  the  market  which 
have  a  pugmill  about  three  feet  long,  and  many  manufacturers  have 
bought  them,  probably  for  cheapness.  In  almost  every  case  they  give 
dissatisfaction  unless  the  clay  is  thoroughly  tempered  before  being 
molded  in  them,  for  the  pugmill  is  entirely  too  short  to  be  effective. 

Molding. — Two  types  of  stiff-mud  machines  are  used,  the  plunger 
.and  the  auger.  In  both  the  clay  is  discharged  in  the  form  of  a  rect- 
angular bar.  The  plunger  machine  is  intermittent  in  it-  action;  the 
auger  is  continuous,  sometimes  intermittent,  and  perhaps  tic  favorite 
method.  The  bar  of  clay  may  be  2^x4-  inches  or  9x4,  according  as  the 
brick  is  to  be  an  end-cut  or  side-cut  one. 

The  capacity  of  an  auger  machine  is  usually  Prom  50,000  to  70,000 
per  day,  but  it  may  be  less  or  more.  Anger  machine  brick-  arc  apl  to 
he  laminated,  which  aives  a  shelly  structure  to  the  brick.     Some  clavs 


98  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

show  this  more  than  others,  and  the  same  clay  may  show  more  lamina- 
tions when  side-cut  than  end-cut.  Very  plastic  clays  usually  laminate 
the  most. 

Auger  machine  brick  are  often  repressed,  especially  if  to  be  used  for 
paving  or  fronts.  If  pressed  brick  are  to  be  made  it  is  important  to 
test  the  clay  on  different  stiff-mud  machines  first  to  determine  which 
works  the  best.  Plate  VIII  shows  an  auger  end-cut  brick  machine 
(fig.  1),  and  a  re-pressing  machine  (fig.  2). 

The  bar  of  clay  as  it  is  cut  up  into  bricks  is  received  on  a  belt  which 
carries  the  brick  to  the  repressing  machines  or  else  to  the  "  off-bearers." 
who  place  them  on  cars  which  are  run  into  a  drying  tunnel.  Stiff-mud 
brick  are  stiff  enough  when  molded  to  permit  of  their  being  piled  6  or 
8  courses  high  on  the  drying  cars  without  crushing  out  of  shape. 

Re-pressing  sharpens  the  form  of  the  brick,  but  adds  considerably  to 
the  cost  of  manufacture. 

The  brick,  when  piled  on  the  cars,  are  run  into  long  tunnels,  which 
are  heated  by  steam,  coal  or  oil  (see  Plate  VII,  Hg.  2,  p.  88).  Recently 
successful  experiments  have  been  made  towards  utilizing  the  waste 
heat  from  the  cooling  kilns  for  drying  the  brick.  The  rapidity  of  the 
drying  varies  from  20  to  50  or  60  or  more  hours  according  to  the  clay. 
Rapid  drying  cracks  many  clays. 

Few  stiff-mud  brick  are  dried  in  the  sun. 

Burning. — This  is  done  either  in  up-draft  or  down-draft  kilns.  The 
wp-draft  kilns  generally  have  permanent  side  walls,  the  ends  and  top 
being  closed  up  with  brick  and  those  at  the  ends  daubed  with  mud. 
Such  kilns  usually  have  a  capacity  of  150,000  to  200,000.  The  up- 
draft  kilns  are  cheaper  to  construct  than  down-draft  ones,  but  there  is- 
a  greater  percentage  of  salmon  brick  obtained.  Figure  1  of  Plate  X 
(p.  101)  shows  an  up-draft  kiln  used  at  the  state  penitentiary  at  Raleigh. 
This  has  permanent  side  walls,  which  are  braced  by  brick  offsets. 

Continuous  kilns  are  sometimes  used.  This  is  the  ideal  method  of 
burning  brick  and  the  cheapest.  They  have  been  used  most  successfully 
abroad  and  are  gradually  coming  into  extended  use  in  this  country.. 
The  continuous  kiln  consists  essentially  of  a  long  chamber  of  oval  form,, 
which  is  divisible  into  compartments  by  means  of  temporary  partitions. 
Each  compartment  has  one  or  two  entrances  for  wheeling  the  green 
brick  in  and  the  burned  brick  out.  There  are  four  or  more  openings,, 
covered  by  caps  in  the  top  of  each  chamber  for  feeding  the  fuel,  as 
will  be  mentioned  later. 

In  the  walls  of  the  kiln  are  a  series  of  flues  connecting  the  chambers 
with  the  chimney,  and  also  by  means  of  dampers,  making  connection 
possible  between  any  two  chambers.  Each  chamber  has  a  capacity  of 
20,000  to  22,000  brick,  and  in  setting  them  vertical  spaces  are  left  under 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  13,  PLATE  VIII. 


FIG.    1.— 3TIFF-MUD  AUGER    END-CUT   BRICK   MACHINE. 

Shows  a  bar  of  clay  issuing  from  the  die  of  the  machine.     This  is  cut  across  by  a  wire  at  proper 

intervals,  thus  dividing  it  into  brick. 


FIG.   2.  — RE-PRESSING   BRICK   MACHINE. 

The  brick  to  be  re-pressed  are  brought  from  the  moulding  machine  on  a  belt  Us  shown  in  the 

foreground),  from  which  they  are  taken  by  a  workman  who  places  them, 

two  at  a  time,  into  the  machine. 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  13.  PLATE  IX. 


FIG.   1.— INTERIOR  VIEW  OF  A  CONTINUOUS   BRICK-KILN. 


FIG.   2.— EXTERIOR   VIEW,   CONTINUOUS   BRICK-KILN. 


BRICK-CLAYS    AND    BRICK    MANUFACTURE.  99 

the  charging  holes  in  the  roof.  As  each  chamber  is  filled  the  temporary 
(often  paper)  partition  between  it  and  the  next  one  is  put  up,  the  object 
of  this  being  simply  to  prevent  the  draft  from  passing  straight  through 
the  whole  kiln. 

After  each  chamber  is  filled  the  two  entrances  are  bricked  up,  leaving 
a  charging  space,  which  is  covered  by  an  iron  door.  The  kiln  is  started 
by  building  a  fire  in  the  doorway  of  the  first  chamber  and  gradually 
heating  it  up  to  the  desired  temperature.  Coal  slack  is  also  charged 
through  the  openings  in  the  top.  Many  manufacturers  no  longer  use 
the  top  openings,  but  feed  all  the  fuel  through  the  doorways. 

The  important  principle  of  the  continuous  kiln  is  that  the  heat  from 
this  burned  chamber  is  conducted  into  the  next  one  either  through  the 
flues  in  the  wall  or  else  through  sheet-iron  pipes  placed  to  connect  the 
roof  openings.  In  this  way  the  heat  raises  the  temperature  of  the  next 
chamber,  so  that  less  fuel  need  be  used.  When  the  kiln  is  once  started 
it  takes  from  200-300  pounds  of  fuel  per  1000  brick. 

The  heat  from  a  burning  chamber  cannot  as  a  rule  be  carried  safely 
through  more  than  three  or  four  chambers  before  taking  it  off  to  the 
chimney.  The  reason  for  this  is  that  the  hot-air  collects  moisture  from 
the  brick  in  these  chambers  which  are  being  heated  up;  it  will  easily 
be  seen  that  if  carried  through  too  many  chambers  the  air  will  lose  so 
much  heat  that  instead  of  gathering  moisture  it  will  begin  to  deposit  it 
on  the  brick. 

It  is  sometimes  necessary  to  aid  the  draft  of  a  continuous  kiln  by 
means  of  a  small  fan.  The  number  of  chambers  in  the  kiln  depends 
on  the  size  of  the  yard  and  available  capital. 

Continuous  kilns  are  used  in  this  country  for  burning  common  and 
front  brick,  paving  brick  and  fire-brick. 

~No  continuous  kilns  are  in  use  in  North  Carolina,  so  that  the  illus- 
trations shown  are  from  one  at  the  Catskill  (N.  Y.)  Paving-Brick  Works. 
Fig.  1  of  Plate  IX  shows  the  interior  view  of  the  kiln,  which  is  empty, 
while  fig.  2  of  the  same  plate  shows  the  exterior  view. 

DRY-PRESS    PROCESS. 

This  method  is  applicable  to  a  variety  of  clays,  but  not  to  very  sandy 
ones,  which  have  little  cohesive  nature.     The  advantages  of  it  are  wide 


to' 


range  of  character  permissible  in  clays  used,  the  brick  made  are  sharp- 
edged  and  smooth,  and  the  green  brick  can  generally  be  set  directly  in 
the  kiln. 

The  disadvantages  of  this  method  are,  the  necessity  of  weathering 
the  clay,  increased  cost  of  plant,  and  limited  capacity. 

Dry-press  brick  when  properly  burned  arc  a-  strong  aa  other  brick, 
but  if  underburned  they  are  easily  affected  by  the  weather. 


100 


CLAY    DEPOSITS    IX    XORTH    CAROLINA. 


Preparation  of  the  Clay. — The  clay  for  making  dry-press  brick  is 
generally  weathered  first.  This  is  accomplished  by  piling  the  clay  up 
under  large  sheds  or  spreading  it  out  over  the  ground  in  a  layer  one  to 
two  feet  thick.  If  possible,  it  is  frequently  best  to  allow  the  clay  to 
weather  for  several  months  or  even  longer,  depending  on  the  nature  of 
the  material.  By  this  weathering  the  moisture  becomes  evenly  dis- 
tributed through  the  clay,  the  frost  breaks  it  up  and  the  decay  of 
organic  material  by  the  disengagement  of  carbonic  acid  produces  the 
same  effect.  The  iron  compounds  may  also  become  further  oxidized. 
Clays  weather  more  actively  in  winter  than  in  summer. 


Fig.  5. — Drt-Pkess  Bkick  Machine. 


When  ready  for  use  the  clay  is  first  pulverized,  usually  in  a  cen- 
trifugal disintegrator  of  the  Steadman  type,  and  then  passed  through 
a  screen  with  meshes  varying  from  one-eighth  to  one-sixteenth  inch, 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN*  13.  PLATE  X. 


iWUHlfr  BR 


FIG.   1 .— UP-DRAFT   BRICK-KILNS,    FOR    BURNING  COMMON    BRICK,   AT  THE  STATE   PENITENTIARY, 
RALEIGH,   N    C.     'See  page  98.) 


FIG.  2— DOWN-DRAFT  BRICK-KILN,   EUDLAY  TYPE.     (See  also  page  141.) 


BRICK-CLAYS    AND    BRICK    MANUFACTURE.  101 

the  finer  mesh  being  used  for  front  brick.  The  clay  should  not  con- 
tain too  much  moisture,  as  otherwise  it  clogs  the  screen.- 

Molding  the  Brick, — The  dry -press  consists  essentially  of  a  steel 
mold  box  with  movable  top  and  bottom.  The  clay  is  fed  into  the 
mold  automatically,  and  the  plunger  descends  into  the  mold  from  above, 
the  pressure  being  applied  by  means  of  a  toggle-joint  or  cam.  After 
the  clay  is  pressed  the  plunger  rises,  as  does  also  the  bottom  of  the  mold, 
until  the  brick  is  level  with  the  table,  on  which  it  is  pushed  forward 
by  the  charger  as  it  advances  to  refill  the  mold.  The  brick  are  set  on 
hand-cars  and  carried  off  to  the  kilns. 

If  the  clay  is  very  dry  the  edges  are  apt  to  crumble,  and  the  brick 
will  not  bear  much  handling.  To  avoid  this  the  clay  is  sometimes  dis- 
charged from  the  screen  into  a  pugmill,  where  it  is  moistened  with 
steam.  This  gives  a  brick  with  sharper  edges  and  one  which  bears 
handling  better.  The  term  semi-dry  press  is  used  when  the  clay  is 
moistened  somewhat. 

There  are  numerous  types  of  dry-press  machines,  among  which  may 
be  mentioned  those  of  the  Boyd  (fig.  5,  p.  100),  Simpson,  Whittaker, 
and  Chambers  patterns.  The  slower  the  pressure  is  applied  in  molding 
the  brick  the  less  air  will  there  be  enclosed  in  it,  and  the  less  will  be 
the  danger  of  its  bursting  by  the  expansion  of  the  air. 

Burning. — Dry-press  brick  are  burned  in  either  up-draft  or  down- 
draft  kilns.  This  process  has  to  be  conducted  very  slowly,  for  both  the 
drying  and  water-smoking  have  to  be  done  in  the  kiln,  and,  on  account 
of  the  dense  nature  of  the  brick,  the  water  can  only  escape  slowly. 
Drying  and  water-smoking  may  therefore  take  from  six  to  eight  days. 
In  burning  front  brick  it  is  important  that  as  few  as  possible  should  lie 
exposed  to  the  direct  action  of  the  flames.  In  up-draft  kiln-  the 
arch  brick  are  generally  warped  and  discolored,  while  in  down-draft 
kilns  the  top  courses  are  generally  fire-flashed  and  also  discolored  from 
the  ashes  of  the  fuel.  These  top  brick  are  harder  burned  than  the 
bottom  ones,  and  while  useless  for  front  brick,  if  not  cracked  they  are 
often  desirable  for  walks  or  sewers. 

The  down-draft  kiln  is  preferable  for  burning  front  brick,  a-  there 
is  less  loss  in  the  form  of  overburned  or  underburned  brick.  Plal  X. 
fig.  2,  shows  the  Eudaly  type  of  down-draft  kiln,  which  is  in  common  use. 


CHAPTER  IX. 
BEICK-CLAY  DEPOSITS  IN  NOKTH  CAEOLIXA. 

CLAYS  IN  BLADEN  COUNTY. 

Near  Prospect  Hall. — Following  down  the  Cape  Pear  river  from 
Fayetteville,  after  passing  Willis  creek,  there  begin  to  appear  large 
quantities  of  black  clay  in  the  bluffs  along  the  river.  One  of  the  best 
sections  is  to  be  seen  in  a  bluff  60  feet  high  on  the  property  of  Wil- 
liam Whitted  at  Prospect  Hall  (see  Plate  XI,  fig.  1,  p.  110). 

The  upper  20  feet  of  the  bluff  are  sand  and  gravel  often  heavily 
stained  with  iron,  but  the  lower  forty  feet  are  mostly  black  clay,  roughly 
separated  into  three  somewhat  lens-shaped  beds,  as  follows: 

Black,  sandy  clay,  8-10  feet  (field  sample  No.  11). 

Sand  and  sandstone,  10  feet. 

Black,  sandy  clay,  8  feet  (field  sample  No.  10). 

Black  clay,  4  feet,  exposed  at  base  of  bluff  (field  sample  No.  12). 

The  upper  black  sandy  clay  of  the  section  (Xo.  11)  has  in  places 
abundant  mica  scales,  and  sometimes  coarse  sand  grains.  It  slakes 
slowly  to  large  scaly  fragments.  Pyrite  and  lignite  are  both  scattered 
sparingly  through  the  clay,  but  the  pyrite  is  mostly  in  small  grains. 
The  addition  of  38/c  of  water  gave  a  mass  that  was  lean  and  gritty. 
This  paste  shrunk  6$  in  drying  and  8^  in  burning,  giving  a  total  shrink- 
age of  14:fo.  Air-dried  briquettes  of  this  paste  had  an  average  tensile 
strength  of  64  lbs.  per  square  inch  and  a  maximum  of  77  lbs.  per 
square  inch.  Incipient  fusion  occurs  at  1900°  F.,  vitrification  at  2100°, 
viscosity  at  2300°.     It  burns  to  a  deep  red,  dense  body. 

The  composition  of  this  clay  is: 

Analysis  of  Brick-clay  {No.  11),  Prospect  Ball. 

Moisture    4.50 

Silica  (total)  56.13 

Alumina j 17.80 

Ferric   oxide    5.85 

Lime 10 

Magnesia 79 

Alkalies    2.45 

Water  (loss  on  ignition)  11.60 

Total    99.22 

Free  sand 27.18 

Total  fluxes   7.29 

Specific  gravity   2.34 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  103 

No.  11  is  similar  to  E"o.  10,  but  contains  more  coars.e  grit,  and  the  mica 
scales  are  abundant.  It  slakes  slowly  to  large  fragments,  and  required 
the  addition  of  22^  of  water  to  make  a  workable  paste,  which  is  very 
lean.  This  paste  shrunk  5$  in  drying  and  8^  in  burning,  giving  a  total 
shrinkage  of  13$.  The  tensile  strength  is  very  low  as  indicated  by  the 
plasticity,  being  on  the  average  only  46  lbs.  per  square  inch,  with  a 
maximum  of  58  lbs.  per  square  inch.  Incipient  fusion  occurs  at  2000° 
F.,  vitrification  at  2150°  F.,  and  viscosity  at  2300°  F.  The  clay  burns 
to  a  deep  red  body. 

Its  composition  is  as  follows: 

Analysis  of  Brick-clay  {No.  10),  Prospect  Hall. 

Moisture    2.80 

Silica   (total)    ' 63.30 

Alumina    15.87 

Ferric  oxide   5.48 

Lime    27 

Magnesia    21 

Alkalies     2.10 

Sulphur    1.78 

Water  (loss  on  ignition)    8.25 

Total     100.36 

Free  sand   57.30 

Total  fluxes  10.11 

Specific  gravity    2.13 

The  organic  matter  is  noticeable  from  the  loss  on  ignition  which  the 
clay  undergoes.  The  total  percentage  of  fluxes  is  greater  than  in  Xo. 
11,  but  their  fluxing  tendency  is  more  than  offset  by  the  sand  present. 

No.  12  is  the  best  clay  of  the  three,  as  it  contains  less  sand,  mica  scales 
and  pyrite.  It  is  also  more  homogeneous,  harder  and  denser.  The  sand 
and  mica  grains  are  mostly  between  the  layers  of  the  clay.  The  clay 
slakes  slowly  to  large  scaly  fragments.  It  soaks  up  a  large  quantity  of 
water,  and  required  40$  to  make  a  workable  mud  that  had  little  plas- 
ticity. This  mud  shrunk  12$  in  drying  and  5$  in  burning,  giving  a 
total  shrinkage  of  17$.  The  air-dried  briquettes  made  from  this  paste 
had  an  average  tensile  strength  of  59  lbs.  per  square  inch  and  a  max- 
imum tensile  strength  of  90  lbs.  per  square  inch,  [ncipiejil  fusion 
occurred  at  1900°  F.,  vitrification  at  2100°  F.,  viscosity  at  2300°  F. 

The  composition  of  the  clay  is  as  follow-: 

Analysis  of  Brick-clay  [No    12),  Prospect  Ball. 

Moisture    4.26 

Silica  (total)   •"'"'■, >•"> 

Alumina    20.8(3 


10-J:  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Ferric   oxide    5.11 

Lime     30 

Magnesia    04 

Alkalies    2.13 

Sulphur    1.18 

Water  (loss  on  ignition)    9.94 

Total    100.07 

Free  sand  15.05 

Total  fluxes   9.36 

Specific  gravity    2.30 

The  chief  objection  to  these  clays  is  their  lean  character.  They  stand 
rapid  heating  and  burn  easily  to  a  dense  red  body. 

If  molded  into  brick,  it  shonld  be  done  by  machinery  that  would  give 
them  good  pressure,  and  not  by  hand.  The  admixture  of  a  more  plastic 
clay  would  be  a  still  better  method  to  follow. 

They  might  possibly  be  worked  for  paving  brick. 

CLAYS   IN    BUNCOMBE    COUNTY. 

Penniman  Clxvy  Bank  near  Emma. — Along  the  line  of  the  Southern 
R.  R.,  southwest  of  Asheville,  on  the  road  to  Murphy,  deposits  of  sedi- 
mentary clays  are  to  be  found  at  a  number  of  localities.  Their  largest 
development  is  at  Emma,  two  miles  west  of  Asheville,  where  consider- 
able quantities  of  brick  are  made  by  W.  R.  Penniman. 

The  section  exposed  in  Penniman's  bank  is  as  follows: 

Upper  red  clay  4  feet. 

Lower  gray  clay   ("  fire-clay  ") 3-10  feet. 

Sand    

The  upper  clay  is  tough,  gritty,  highly  colored,  and  in  places  seems 
to  grade  downward  into  the  under  gray  clay. 

The  upper  or  brick  clay  slakes  quickly  to  grains  of  sand  and  mica  and 
fine  aluminous  mud. 

The  addition  of  20^  of  water  gave  a  workable  paste  of  somewhat 
plastic  feel.  This  paste  shrunk  9$  in  drying  and  4$  in  burning,  giving 
a  total  shrinkage  of  13^.  The  air-dried  briquettes  made  from  this  mud 
had  an  average  tensile  strength  of  63  lbs.  per  square  inch,  with  a  max- 
imum of  80  lbs.  per  square  inch.  Incipient  fusion  occurred  at  2000° 
E.,  vitrification  at  2200°  E.,  and  viscosity  at  2400°  E. 

The  clay  burns  to  a  good  red  body.     The  following  is  the  analysis: 

Analysis  of  upper  Brick-clay  (iVT'>.  59).  Penniman's. 

Moisture    1.15 

Silica  (total)   66.27 

Alumina    19.95 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  105 

i  Ferric  oxide   3.16 

Ferrous  oxide   07 

Lime    20 

Magnesia    32 

Alkalies    1.85 

Water  (loss  on  ignition) <;.17 

Total    99.74 

Clay  substance   49.34 

Free  sand 50.40 

Total  fluxes   0.20 

Specific  gravity    2.50 

The  iron  is  mostly  oxidized,  as  will  be  seen  from  the  analysis  and 
also  indicated  by  the  color  of  the  clay. 

The  under  clay  at  this  yard  goes  by  the  name  of  fire-clay.  It  is  a 
coarse-grained  clay,  full  of  mica  scales  and  small  angular  quartz  grain-. 
In  water  it  slakes  quickly  and  completely,  and  on  the  addition  of  28$ 
of  water  gave  a  workable  and  moderately  plastic  paste  which  shrunk 
7$  in  drying  and  4$  in  burning,  giving  a  total  shrinkage  of  11$.  The 
average  tensile  strength  of  the  air-dried  briquettes  made  from  this  clay 
was  58  lbs.  per  square  inch,  with  a  maximum  of  60  11>-. 

Incipient  fusion  occurs  at  2050°  F.,  vitrification  at  2250°  F.,  ami 
viscosity  at  2450°  F.  The  clay  burns  gray  buff.  ■  The  composition  of 
the  clay  is  as  follows : 

Analysis  of  lower  Brick-clay  {"fire-clay")  [No.  58),  Peniriman's. 

Total  portion.    Insoluble  portion. 

Moisture    80 

Silica  (total)    70.60  55.70 

Alumina     17.21  .40 

Ferric  oxide   3.44  .5G 

Lime    10 

Magnesia    07 

Alkalies    2.45  1.32 

Water  (loss  on  ignition) 5.00 

Total    . 99.73  57.98 

Total   fluxes    7. m 

Specific    gravity    2.48 

From  the  above  analysis  we  obtain: 

Clay  substance   U.75 

Quartz    54.30 

Feldspar 3.68 


106  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

This  clay  is  not  unlike  the  bottom  clay  at  Bethania,  but  contains 
more  free  sand.  The  grains  of  the  latter  are  mostly  quartz,  as  seen 
from  the  rational  analysis. 

This  type  of  clay  is  not  uncommon  in  ]N"orth  Carolina,  the  clays  at 
Grover  being  of  this  kind,  but  they  contain  less  iron.  The  predom- 
inant character,  however,  is  the  fine-grained  clay  substance  with  the 
coarse  quartz  grains  scattered  through  it, 

Mr.  Penniman  uses  the  upper  clay  for  making  common  brick  and 
also  for  re-pressed  brick,  for  it  burns  to  a  good  red  color.  The  brick  are 
molded  in  a  Sword's  machine,  dried  in  the  sun  and  burned  in  up-draft 
open  kilns  with  permanent  side  walls,  of  185,000  capacity.  The  fuel 
is  coal.   ■ 

The  brick  made  from  the  lower  clay  are  burned  in  the  same  kiln  and 
at  the  same  time  as  the  red  clay.  They  are  re-pressed.  The  chief  use 
of  the  lower  clay  brick  is  for  boiler  and  furnace  foundations  and  for 
furnaces  requiring  only  a  low  degree  of  heat.  The  bricks  are  white 
or  yellowish-white,  and  not  burned  very  hard. 

It  is  probable  that  a  mixture  of  the  upper  and  lower  clay  would  make 
a  paving  brick,  although  if  a  more  plastic  and  slightly  more  fusible  clay 
than  the  upper  one  could  be  mixed  with  the  lower  clay,  still  better 
results  would  be  obtained.  Such  clays  are  to  be  found  in  many  of  the 
lowlands  along  the  valleys  near  Asheville. 

Clays  near  Asheville  and  Biltmore. — The  French  Broad  river 
near  Asheville  is  bordered  at  several  points  by  broad  stretches  underlain 
by  clays  of  good  quality  for  various  purposes.  Such  a  deposit  has  been 
worked  at  Biltmore  with  eminent  success,  the  products  being  common 
and  pressed  brick,  drain  tile,  and  paving  brick.  The  deposit  has  been 
covered  up  now  to  permit  land  improvements,  but  the  same  belt  of  clay 
land  borders  the  river  at  other  points. 

It  should  be  noted  that  the  methods  and  machinery  used  at  Biltmore 
were  of  the  most  approved  type. 

Poor  products  may  result  very  often  as  much  from  carelessness  in 
manipulation  and  the  use  of  the  wrong  appliances  and  methods  as  in 
the  use  of  improper  clay. 

The  other  brickyards  around  Asheville  are  working  residual  clays  for 
making  common  brick  to  supply  a  local  demand. 

Clays  near  Fletcher. — The  Buncombe  Brick  Co.  at  this  locality 
is  engaged  in  the  manufacture  of  both  common,  pressed  and  paving 
brick.  Their  main  bank  is  a  light  gray  clay  of  slightly  plastic  and 
somewhat  gritty  feel.  It  is  fine-grained  and  slakes  slowly.  The  addi- 
tion of  25.5$  of  water  was  required  to  give  a  workable  mass,  which 
shrunk  4$  in  drying  and  7$  in  burning,  making  a  total  shrinkage  of  11$. 
The  air-dried  briquettes  had  an  average  tensile  strength  of  37  lbs.  per 
square  inch  and  a  maximum  of  40  lbs.  per  square  inch. 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  107 

Incipient  fusion  occurs  at  2000°  F.,  vitrification  at  2200°  F.,  and 
viscosity  at  2400°  F. 

The  chemical  composition  of  the  clay  is : 

Analysis  of  Brick-clay  {No.  65),  near  Fletcher. 

Moisture 1.10 

Silica  (total)   75.08 

Alumina    13.73 

Ferric  oxide 3.47 

Lime 30 

Magnesia 17 

Alkalies 1.48 

Water  (loss  on  ignition)    4.65 

Total    99.98 

Clay  substances   45.18 

Free  sand  55. SO 

Total  fluxes   5.42 

Specific  gravity    2.41 

CLAYS   IN    BURKE    COUNTY. 

Near  Morganton. — The  clay  underlying  the  terrace  along  the  river 
two  miles  west  of  the  town  becomes  more  sandy  in  character  towards 
the  river.  A  sample  from  the  brickyard  of  Mr.  McDowell  along  the 
river  had  60^  of  sand,  while  along  the  road,  back  from  the  river,  there 
was  only  54^. 

The  clay  as  exposed  in  McDowell's  brick-clay  bank  (Xo.  52)  is  a 
loose,  sandy,  coarse  clay,  with  abundant  mica  scales  and  quartz  grains. 
It  slakes  very  quickly  and  completely  to  its  component  grains.  The 
addition  of  22$  of  water  gave  a  lean  but  workable  mud  which  shrunk 
6$  in  drying  and  5^  in  burning,  giving  a  total  shrinkage  of  IK. 

The  average  tensile  strength  of  the  air-dried  briquettes  was  50  lbs. 
per  square  inch,  with  a  maximum  of  83  lbs. 

Incipient  fusion  occurs  at  1950°  F.,  vitrification  at  2100°  F.,  and 
viscosity  at  2250°  F.     The  clay  burns  dark  red  at  2100°  F. 

The  analysis  of  it  gave: 

Analysis  of  Brick-clay  {No.  52),  McDuicelVs  day  bank. 

Moisture    1.80 

Silica  (total)    67.03 

Alumina    L6.88 

Ferric  oxide  ,; 50 

Lime 1-00 

Magnesia    1.16 

Alkalies    90 

Water  (loss  on  ignition)   4.78 

Total    100.05 


10S  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Clay  substance   39.90 

Free  sand , 60.05 

Total  fluxes   9.56 

Specific  gravity    2.61 

The  clay  is  used  for  making  common  brick,  but  they  are  molded  in 
ordinary  hand-molds  and  burned  barely  to  incipient  fusion;  with  more 
care  and  better  machinery  a  very  good  brick  could  be  made  from  it. 

Probably  there  could  be  found  a  more  plastic  clay  in  the  lowlands 
between  the  railroad  and  the  Xorth  Carolina  Insane  Asylum. 

CLAY  IN  CLEVELAND  COUNTY. 

Xear  Grover. — Occurring  in  the  region  around  Grover  are  beds 
of  surface  clays  which  have  no  connection  with  the  so-called  fire-clays 
previously  mentioned  (p.  81).  At  the  works  of  the  Cleveland  Brick 
Company  just  south  of  Grover,  one  of  these  beds  has  been  opened  up 
and  consists  of  an  upper  bed  of  tough,  red,  mottled  clay,  6  feet  thick, 
and  an  under  bed  of  very  plastic  clay  not  less  than  3  feet  thick. 

The  under  clay  (No.  46)  is  a  gritty  clay  with  small  mica  flakes  and 
coarse  sand  grains.  It  is  slow  in  slaking.  35$  of  water  was  required  to 
give  a  workable  mass  that  shrunk  9$  in  drying  and  6.5$  in  burning, 
giving  a  total  shrinkage  of  15.5$.  Air-dried  briquettes  of  the  clay 
had  an  average  tensile  strength  of  98  lbs.  per  square  inch  and  a  max- 
imum of  115  lbs.  per  square  inch.  Incipient  fusion  occurs  at  1900"  F., 
vitrification  at  2100°  F.,  and  viscosity  at  2300°  F.  The  clay  burns 
a  rather  light  red.    • 

The  analysis  of  the  clay  gives: 

Analysis  of  Cleveland  Brick  Co's.  under  Clay  [Wo.  46),  just  S.  of  Grocer. 

Moisture 1.18 

Silica  (total)   61.75 

Alumina    23  30 

Ferric  oxide    3.34 

Ferrous  oxide   50 

Lime     27 

Magnesia    25 

Alkalies    1.31 

Water  (loss  on  ignition)   7.75 

Total     99.65 

Clay  substance    60.62 

Free  sand  39.05 

Total  fluxes   5.67 

Specific  gravity    2.36 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  109 

The  upper  clay  is  far  less  plastic,  but  very  tough.  It  also  required 
26fo  of  water  to  make  a  workable  paste,  which  was  gritty  to  the  feel 
and  somewhat  plastic.  This  clay  shrunk  7.5$  in  drying  and  5#  in 
burning,  giving  a  total  shrinkage  of  12.5^.  The  average  tensile 
strength  of  the  air-dried  briquettes  was  42  lbs.  per  square  inch  with  a 
maximum  of  51  lbs.  Incipient  fusion  occurred  at  1950°  F.,  vitrifica- 
tion at  2150°  F.,  and  viscosity  at  2350°  F.     The  clay  burns  red. 

The  composition  of  this  clay  is  as  follows: 

Analysis  of  Cleveland  Brick  Co.'s  upper  Clay  (No.  47),  just  S.  of  Grover. 

Moisture    G.°> 

Silica  (total)   65.45 

Alumina    20.02 

Ferric  oxide    4.18 

Lime 25 

Magnesia    2!> 

Alkalies    1.51 

Water  (loss  of  ignition)  6.5S 

Total    98.91 

Clay  substance   47.06 

Free  sand  51.45 

Total  fluxes   0.23 

Specific  gravity 2.61 

While  the  upper  clay  is  not  as  strong  as  the  lower,  still  it  burn-  easier 
to  a  red  brick  and  shrinks  less  in  burning. 

The  pit  is  about  300  feet  from  the  yard,  and  the  clay  i-  hauled  in 
carts.  The  tempering  is  done  in  a  long  open  pugmill  of  Chambers's 
manufacture.  Molding  is  done  in  a  Chambers's  auger  automatic  end- 
cut  machine.  A  pair  of  rolls  were  formerly  used  for  breaking  the  claw 
but  were  found  very  unsatisfactory.  A  standard  dryer  heated  by 
steam-pipes  is  used.  Exhaust  steam  is  used  in  the  daytime  and  live 
steam  at  night. 

The  brick  are  burned  either  in  scove  kiln-  or  circular  down-draft 
ones.  They  are  16  feet  in  diameter,  and  there  is  one  stack  for  every 
two  kilns,  but  Mr.  Eskridge  is  about  to  put  a  aumber  of  small  chim- 
neys on  each  kiln. 

The  fire-brick  are  burned  in  the  circular  kiln.  They  are  used  for 
the  roof  of  the  roasting  furnaces  at  the  Blacksburg  (South  Carolina) 
acid  works,  and  wear  well.  The  furnace  has  a  diameter  of  2<>  feet, 
and  the  rise  from  circumference  to  centre  is  s   inches. 

The  hard  red  brick  are  used  around  the  acid  works  and  resist  the 
action  of  the  acid  very  well. 

This  clav  is  not  unlike  many  of  the  alluvial  clays  in  other  parts  of 


110  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

North.  Carolina,  and  they  show  very  well  the  influence  of  proper  work- 
ing and  machinery  in  producing  good  results. 

CLAY   IN    CUMBERLAND    COUNTY. 

Near  Fayetteville. — South  of  the  town  are  extensive  beds  of  sedi- 
mentary clays,  whose  general  section  involves  2-3  feet  of  coarse  sand 
underlain  by  at  least  eight  feet  of  clay,  and  sometimes  probably  more. 
The  clays  are  best  exposed  at  Poe  &  Bros.'  yard,  a  half  mile  south  of 
Fayetteville.  The  clay  as  exposed  here  is  a  fine-grained,  tough,  bluish- 
white  clay  with  frequent  thin  iron  stains,  which  give  it  a  mottled 
appearance.  In  some  portions  of  the  bank  the  clay  is  very  smooth 
and  free  from  iron  stains,  and  has  been  used  for  stoneware.  ('Plate  XI, 
fig.  2.) 

At  the  south  of  the  pit  is  a  bed  of  very  tough  clay,  fine-grained  and 
broken  by  numerous  small  joints  running  in  every  direction.  This  por- 
tion is  not  used,  as  it  is  claimed  to  be  too  tough  to  work. 

A  sample  of  the  average  run  of  the  bank,  excluding  the  top  sand  and 
tough  clay,  which  is  not  used,  showed  the  clay  to  be  a  somewhat  gritty, 
medium-grained,  tough  clay  which  slakes  quickly  to  grains  ^-tOw*11 . 
in  diameter.  It  required  the  addition  of  28 fo  of  water  to  make  a  work- 
able mud,  which  felt  quite  plastic.  This  mass  shrunk  8.5$  in  drying 
and  5fo  in  burning,  giving  a  total  shrinkage  of  13. 5£.  The  air-dried 
briquettes  of  this  paste  had  an  average  tensile  strength  of  14-1  lbs.  per 
square  inch  and  a  maximum  of  175  lbs.  per  square  inch. 

Incipient  fusion  occurs  at  1900°  F.,  vitrification  at  2050"  F.,  and 
viscosity  at  2200°  F.     The  clay  burns  deep  red. 

The  chemical  composition  of  the  clay  is  as  follows : 

Analysis  of  Pot's  Brick-clay  {No.  14),  y2  mile  S.  of  Fayettetille. 

Moisture    2.48 

Silica  (total)   64.93 

Alumina    17.0S 

Ferric  oxide 5.57 

Lime    43 

Magnesia    59 

Alkalies    3.85 

Water  (loss  of  ignition)  6.58 

Total    101.51 

Clay  substance 53.13 

Free  sand 45.90 

Total  fluxes  10.44 

Specific  gravity 2.55 

A  sample  of  the  so-called  "  tough  "  clay  was  also  tested  with  the 
following  results.     It  is  a   dense,  somewhat  gritty  clay  which  slakes 


s.1 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  13,  PLATE  XL 


FIG.   1.— BLACK  CLAY  ALONG  CAPE   FEAR   RIVER,    AT   PROSPECT   HALL. 
(See  page  102.) 


FIG.   2.  — POE   BROTHERS'   CLAY    BANK,    FAYETTEVILLF.,   N.   C. 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  Ill 

slowly  to  rounded  granules  of  variable  size,  mostly  above  o  in.  Little 
mica  was  noticeable..  It  required  the  addition  of  28.5^  of  water  to 
make  an  easily  worked  paste,  which  shrank  9.8$  in  drying  and  7<  in 
burning,  giving  a  total  shrinkage  of  16.8$.  Air-dried  briquettes  of  this 
clay  had  an  average  tensile  strength  of  84  lbs.  per  square  inch  and  a 
maximum  of  120  lbs.  per  square  inch.  Incipient  fusion  occurs  at 
1850°  F.,  vitrification  at  2050°  F.,  and  viscosity  at  2250°  F.  The  clay 
burns  deep  red,  and  requires  somewhat  slow  heating  to  prevent  crack- 
ing.    The  composition  of  the  clay  as  shown  by  analysis  is  as  follow-: 

Analysis  of  the  "tough  clay1'   [No.  15),  Poe's  bank,  l/2  mile  S.  of  Fayetteville. 

Moisture    3.23 

Silica  (total)   58.17 

Alumina    20.10 

Ferric   oxide 7.43 

Lime     00 

Magnesia    77 

Alkalies 2.60 

Water  (loss  of  ignition)    7.34 


Total    100.24 

Clay  substance    48.09 

Free  sand   52.15 

Total  fluxes   11.40 

Specific  gravity    2.45 

The  greater  toughness  of  this  clay  is  due  to  its  density. 

This  "  tough  clay  "  could  probably  be  mixed  advantageously  with 
the  other.  As  this  clay  is  manufactured  into  a  very  good  brick,  it  may 
be  well  to  mention  the  method  followed.  The  clay  and  sand  are  first 
dumped  into  soak  pits.  From  these  they  are  shoveled  into  a  Penfield 
plunger  machine  and  issue  from  this  onto  the  cutting  table,  where  they 
are  cut  up  into  brick,  the  frame  carrying  the  cutting  wires  being  oper- 
ated by  hand-power.  The  drying  is  usually  done  on  pallets  and  pro- 
ceeds very  slowly.  The  burning  is  done  in  permanent  side-wall,  up- 
draft  kilns,  having  a  capacity  of  170,000.  Re-pressing  the  brick  has 
been  attended  with  favorable  results. 

CLAY   IN    FORSYTH    COUNTY. 

Near  Bethania. — The  largest  brick-making  plain  in  the  State  is  sit- 
uated at  this  locality.  It  is  owned  by  Messrs.  Carter  and  Shepard. 
(Plate  XII,  fig.  1,  p.  120.) 

The  clay  bank  adjoins  the  yard  and  consists  of  a  gray  clay,  the  up]  er 
portions  of  which  are  intermixed  with  the  wash  of  residual  clay  fr<  m 
the   neighboring   slopes.     The    lower    portion,    of    which    there   is    an 


112  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

abundance,  is  much  superior  to  the  top  mixture,  and  the  two  have  been 
tested  separately  to  determine  their  relative  advantages. 

The  lower  clay  (32)  is  tough,  somewhat  coarse-grained,  with  grains 
of  quartz  and  small  mica  scales.     It  slakes  slowly  to  grains. 

The  addition  of  25^  of  water  gave  a  very  plastic,  workable  mass, 
which  shrunk  10$  in  drying  and  an  additional  5$  in  burning,  giving  a 
total  shrinkage  of  15#.  The  tensile  strength  of  the  air-dried  briquettes 
showed  an  average  of  127  lbs.  per  square  inch  and  a  maximum  of  160 
lbs.  per  square  inch. 

Incipient  fusion  occurs  at  1900°  F.,  vitrification  at  2100°  F.,  and 
viscosity  at  2300°  F.  The  clay  burns  buff  to  red,  dependent  on  the 
temperature. 

The  composition  of  the  clay  is  as  follows : 

Analysis  of  lower  Brick-clay  (No.  32),  Bethania. 

Moisture    90 

Silica  (total)    64.39 

Alumina 19.11 

Ferric  oxide 5.39 

Lime    80 

Magnesia    22 

Alkalies     1.72 

Water  (loss  on  ignition)    7.75 

Total    100.28 

Clay  substance  53.18 

Free  sand  46.60 

Total  fluxes  8.13 

Specific  gravity   2.50 

The  upper  mixture  is  a  lean,  stiff,  sandy  clay  which  slakes  easily  to 
irregular  grains  and  scales.  It  required  27/£  of  water  to  give  a  work- 
able mud,  which  was  lean  and  gritty  to  the  feel.  This  paste  shrank 
8.5$  in  drying  and  6^  in  burning,  giving  a  total  shrinkage  of  11.5^. 
The  air-dried  briquettes  had  an  average  tensile  strength  of  65  lbs.  per 
square  inch  and  a  maximum  of  89  lbs.  per  square  inch.  Incipient 
fusion  occurred  at  2000°  F.,  vitrification  at  2150°  F.,  and  viscosity  at 
2300°  F.  The  clay  burns  to  a  deep  red.  Its  composition  is  shown  by 
the  following  analysis: 

Analysis  of  the  upper  Brick-clay  {No.  33),  Bethania. 

Moisture    1.85 

Silica  (total) 55.S1 

Alumina    20.06 

Ferric  oxide    11.79 

Lime   33 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  113 

Magnesia    1G 

Alkalies    1.42 

Water  (loss  on  ignition)  8.80 

Total    100.22 

Clay    substance    c>7.-14 

Free  sand  32.78 

Total  fluxes  13.70 

Specific  gravity    2.51 

The  upper  clay  contains  more  iron  and  burns  to  a  deeper  red,  but 
does  not  possess  the  tenacity  or  plasticity  that  the  lower  clay  does. 

Carter  and  Shepard's  Clay  Bank. — This  clay  at  Bethania  is  used 
for  brick  and  drain  tile.  It  is  first  put  through  rolls  and  then  a  pugmill, 
after  which  it  is  molded  in'  a  Steele  auger  machine.  The  drying  is  done 
either  on  pallet  racks  or  on  heated  floors.  The  brick  are  burned  in  a 
Morrison  kiln  and  are  of  a  deep  red  color,  but  full  of  lamination-. 

If  the  clay  were  prepared  more  thoroughly,  and  more  of  the  under 
clay  used,  it  would  probably  give  better  results. 

CLAY    IN    GASTON    COUNTY. 

IsTear  Mount  Holly. — The  terraces  along  the  Catawba  river  are  well 
developed  around  Mount  Holly  and  furnish  an  abundance  of  clay. 
About  one-quarter  mile  south  of  town  this  clay  has  been  opened  up  for 
the  manufacture  of  brick.  The  deposit  lies  at  the  shore  line  of  the 
terrace  and  about  35  feet  above  the  river.  It  is  not  less  than  seven 
feet  thick  and  underlain  by  sand  and  gravel.  Brick  were  formerly 
made  from  it  by  Holobaugh,  but  the  yard  is  no  longer  running. 

The  clay  is  somewhat  gritty  and  slakes  slowly  but  completely.  A  few 
mica  scales  are  scattered  through  it. 

The  addition  of  29^  of  water  gave  a  very  plastic  paste,  which  shrunk 
8^  in  drying  and  4.5^  in  burning,  giving  a  total  shrinkage  of  12. ."»'/. 
The  average  tensile  strength  of  the  air-dried  briquettes  was  131  lbs. 
per  square  inch  with  a  maximum  tensile  strength  of  L60  lbs.  per  square 
inch.  Incipient  fusion  occurs  at  1950°  F.,  vitrification  at  2100  I"., 
and  viscosity  at  2250°  F.     The  clay  burns  to  a  close  red  body. 

The  analysis  of  this  clay  yielded  as  follows: 

Analysis  of  Brick-clay  {No.  60),  )i   mile  S.  of  Mt.  Holly. 

Moisture    1.43 

Silica  (total)    (51.28 

Alumina    20.83 

Ferric  oxide   5.51 

Lime     ''•' 

Magnesia    14 

8 


114  CLAY    DEPOSITS    IX    XOKTH    CAROLINA. 

Alkalies    81 

Water  (loss  on  ignition)  8.75 

Total     99.27 

Clay  substance    50.99 

Free  sand  19.05 

Total  fluxes   6.98 

Specific  gravity   2.17 

This  clay  should  make  a  first-class  brick  that  would  stand  re-pressing. 
In  composition  and  physical  properties  it  is  closely  similar  to  the 
clay  for  pottery  dug  northwest  of  Lincolnton,  but  is  more  san^y  in  its 
nature. 

CLAY   IN   GUILFORD    COUNTY. 

JSTear  Greensboro. — Both  residual  and  sedimentary  clays  occur  in 
abundance  around  the  town,  and  both  are  utilized  by  the  brick  manu- 
facturers. The  Greensboro  Brick  and  Tile  Company's  yard  is  located 
on  the  northern  edge  of  the  town  along  the  road  to  Pomona.  The  clay 
is  a  reddish  residual  clay  resulting  from  the  decomposition  of  gneissic 
rock,  and  opened  up  to  a  depth  of  8  feet.  This  material  is  somewhat 
more  sandy  in  portions  of  the  bank,  but  all  of  it  is  soft.  A  sample  of 
this  clay  was  found  to  slake  easily  to  its  component  grains.  It  required 
28^  of  water  to  produce  a  workable  mass,  which  shrunk  9$  in  drying 
and  6$  in  burning,  making  a  total  shrinkage  of  15$.  This  paste  was 
moderately  plastic.  Air-dried  briquettes  of  the  clay  had  an  average  ten- 
sile strength  of  85  lbs.  per  square  inch  and  a  maximum  of  96  lbs.  per 
square  inch.  Incipient  fusion  occurs  at  2050°  F.,  vitrification  at  2250° 
F.,  and  viscosity  at  2450°  F.     The  clay  burns  to  a  red  body. 

Its  composition  is  as  follows: 

Analysis  of  Greensboro  Brick  &  Tile  Co's.  Clay  {No.  21). 

Moisture    1.64 

Silica  (total)    56.81 

Alumina    20.62 

Ferric  oxide   6.13 

Lime    65 

Magnesia    58 

Alkalies    4.47 

Water  (loss  on  ignition)  S.60 

Total    99.50 

Clay  substance   5S.S5 

Free  sand  40.65 

Total  fluxes 11.83 

Specific  gravity    2.44 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  115 

The  high  per  cent,  of  alkalies  is  evidently  due  to  much  undecom- 
posed  feldspar.  A  very  good  building  brick  is  made  from  this  clay. 
The  plant  includes  a  pair  of  rolls,  Freese  disintegrator  and  Treese  side- 
cut  auger  machine.  The  brick  are  dried  on  a  brick  floor  heated  by  hot 
air  passing  through  flues  underneath.  They  have  three  Morrison  kilns 
in  which  soft  coal  is  used.     Re-pressing  has  been  tried  with  fair  results. 

Dean's  brickyard  is  on  the  southern  side  of  town,  and  the  clay  is  very 
similar  to  that  at  the  Greensboro  Brick  and  Tile  Company's  yard. 

It  is  a  lean,  gritty  clay,  with  abundant  grains  of  quartz,  feldspar  and 
mica.     In  water  it  slakes  easily  to  its  component  grains. 

It  absorbed  28$  of  water  in  being  worked  into  a  paste,  which  shrunk 
lOfc  in  drying  and  6$  in  burning,  giving  a  total  shrinkage  of  16$.  The 
average  tensile  strength  of  air-dried  briquettes  was  66  lbs.  per  square 
inch,  while  the  maximum  was  77  lbs.  per  square  inch.  Incipient  fusion 
occurred  at  2100°  F.,  vitrification  at  2300°  F.,  and  viscosity  at  2400°  F. 
The  clay  burns  red.     Its  composition  is  shown  by  the  following  analysis: 

Analysis  of  Dean's  Bruk-clay  {No.  30)  pit,  Greensboro . 

Moisture    1.90 

Silica  (total) 59.27 

Alumina    22.31 

Ferric   oxide    6.69 

Lime    25 

Magnesia    13 

Alkalies    90 

Water  (loss  on  ignition) 9.00 

Total    100.45 

Clay  substance   67.20 

Free  sand   33.25 

Fluxes    7.97 

Specific  gravity   2.46 

This  clay  is  used  for  the  manufacture  of  common  brick.  It  is  tem- 
pered in  a  ring  pit,  molded  by  hand,  dried  in  the  sun,  and  burned  in 
scove  kilns.     The  product  is  burned  little  beyond  incipient  fusion. 

Watson's  brickyard  uses  the  same  clay  and  methods  as  are  used  at 
Dean's  yard,  just  described. 

Kirkpatrick's  brickyard  is  situated  along  North  Buffalo  creek,  and 
the  clay  is  a  portion  of  the  deposit  to  be  found  more  or  less  continuously 
along  the  creek  all  the  way  up  to  Pomona.  It  i<  a  gray,  gritty  clay, 
dense  and  tough,  and  slakes  slowly  to  irregular  granules. 

It  required  the  addition  of  3(K  of  water  to  make  ;i  workable  paste, 
which  shrunk  11$  in  drying  and  :>'<  in  burning,  giving  a  total  shrinkage 
of  lQfc.     Air-dried  briquettes  of  the  very  plastic  paste  had  an  average 


116  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

tensile  strength  of  220  lbs.  per  sqnare  inch  with  a  maximum  of  232  lbs. 
per  square  inch.  Incipient  fusion  occurs  at  1900°  F.,  vitrification  at 
2100°  F.,  and  viscosity  at  2300°  F.  It  burns  to  a  dense  red  body,  but 
requires  slow  heating.  The  composition  is  indicated  by  the  following 
analysis : 

Analysis  of  Kirkpatrick' s  Brick-clay  {No.  31),  Greensboro. 

Moisture    1.50 

Silica  (total)    69.70 

AlumiDa    12.87 

Ferric  oxide  6.13 

Lime    2.55 

Magnesia    57 

Alkalies     2.79 

Water  (loss  on  ignition)    4.08 

Total    100.19 

Clay  substance    35.27 

Free  sand    64.92 

Fluxes     12.04 

Specific  gravity    2.48 

The  clay  is  discharged  directly  into  a  steel  end-cut  auger  machine, 
heated  on  drying  floors,  and  burned  in  scove  kilns. 

CLAY   IN    HALIFAX    COUNTY. 

Near  Roanoke  Rapids. — There  has  been  considerable  demand  for 
brick  at  this  locality  for  use  in  the  construction  of  large  cotton  mills 
being  erected  at  this  point.  The  clays  used  occur  along  or  near  the 
Roanoke  river,  a  few  hundred  yards  south  of  the  cotton  mills.  The 
section  is  in  general  as  follows: 

Yellowish  sandy  clay  (sample  No.  1) 2  to  5  ft. 

Plastic  clay  (exposed)  (sample  No.  2)   6  to  S  ft. 

This  upper  sandy  clay  is  coarse-grained  and  contains  numerous  small 
concretions  of  sand  cemented  by  limonite.  A  sample  of  this  upper  clay 
was  tested  with  the  following  results:  The  sandy,  moderatelv  coarse- 
grained yellow  clay  slaked  extremely  slowly  on  account  of  its  density. 
It  required  25^  of  water  to  produce  a  workable  paste,  which  to  the  feel 
was  very  lean.  This  paste  shrunk  Sfc  in  drying  and  5$  in  burning, 
giving  a  total  shrinkage  of  13#.  Air-dried  briquettes  of  the  mud  had 
an  average  tensile  strength  of  46  lbs.  per  square  inch  and  a  maximum 
strength  of  50  lbs.  per  square  inch.  Incipient  fusion  occurred  at  1900° 
F.,  vitrification  at  2050°  F.,  and  viscosity  at  2250°  F. 

At  1900°  the  clay  burned  to  a  reddish,  porous  body,  but  at  2050°  it 


s 


BRICK-CLAY    DEPOSITS    EN    NORTH    CAROLINA.  117 

was  fairly  dense,  but  deep  reddish  brown.     The  little  ferruginous  con- 
cretions fuse  to  black  spots  in  burning. 

The  following  is  the  composition  of  this  upper  sandy  day. 

Analysis  of  upper  sandy  Clay  (JVo.  1),  Roanoke  Rapids. 

Moisture    1.63 

Silica  (total)    67.55 

Alumina 13.16 

Ferric  oxide   S.54 

Lime    17 

Magnesia    28 

Alkalies    2.65 

Water  (loss  on  ignition)  5.08 

Total    99.06 

Clay  substance   41.98 

Free   sand    57.08 

Total  fluxes   11.64 

Specific  gravity    2.39 

The  insoluble  residue  ("  free  sand  ")  in  the  above  indicates  the  sandy 
character  of  the  clay  and  the  reason  of  its  leanness  and  low  tensile 
strength. 

The  underlying  clay  is  less  sandy  and  feels  far  more  plastic.  It  con- 
tains a  few  small  mica  scales.  It  slakes  moderately  fast  to  grains  of 
small  size,  and  is  not  a  very  dense  clay.  The  following  description  ap- 
plies to  the  part  of  this  lower  clay  (6  to  8  feet  thick)  exposed  and  used 
in  the  pits  at  Roanoke  Rapids,  and  here  designated  the  middle  clay 
(sample  No.  2): 

It  required  26.5^  of  water  to  make  a  workable  mass,  which  was  highly 
plastic.  This  mud  shrunk  10$  in  drying  and  an  additional  5$  in  burn- 
ing, giving  a  total  shrinkage  of  15v.  Air-dried  briquettes  made  from 
this  paste  exhibited  an  average  tensile  strength  of  151  pounds  per  square 
inch  and  a  maximum  of  168  pounds  per  square  inch.  Incipient  fusion 
occurs  at  1900°  F.,  vitrification  at  2050°  F.,  and  viscosity  at  2250°  F. 
The  clay  burns  to  a  red  body,  much  smoother  than  the  preceding  sample. 

The  increased  plasticity  is  very  noticeable,  and  due  no  doubt  in  part 
to  the  smaller  quantity  of  sand  present  and  perhaps  greater  fineness  of 
the  grains. 

The  following  is  the  composition  of  the  clay: 

Analysis  of  the  middle  Brick-clay  [No.  2),   Roanoke  Rapids. 

Moisture    2.45 

Silica    (total)    65.58 

Alumina 11.04 

Ferric   oxide    5.76 

Lime     '  - 

Magnesia -s 


118  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Alkalies    2.30 

Water  (loss  on  ignition) 5.58 

Total    99.71 

Clay  substance   56.70 

Free  sand  31.50 

Total  fluxes   9.06 

Specific  gravity   2.59 

Another  sample  (No.  3)  of  this  lower  clay,  and  here  designated  the 
under  clay,  represents  its  lower  portion,  extending  for  several  feet 
below  the  level  of  the  present  floor  of  the  brickyard  at  Roanoke  Rapids, 
and  was  collected  to  show  the  uniformity  of  this  lower  clay.  Its  gen- 
eral character  may  be  seen  from  the  following  description : 

To  the  feel  the  lower  sample  of  the  under  clay  was  about  the  same 
in  grittiness  and  fineness  of  grain  as  the  upper  part  of  this  lower  clay 
stratum  (No.  2),  but  the  plasticity  was  seemingly  greater.  The  clay 
slaked  rather  readily  to  irregular  granules,  requiring  26$  of  water  added 
to  it  in  order  to  produce  a  workable  paste,  which  was  very  plastic.  This 
paste  shrank  10.6^  in  drying  and  5$  in  burning,  making  a  total  shrink- 
age of  15.6/1  The  average  tensile  strength  of  the  air-dried  briquettes 
was  206  lbs.  per  square  inch,  and  the  maximum  strength  218  lbs.  per 
square  inch. 

Incipient  fusion  occurred  at  1900°  F.,  vitrification  at  2050°  I\,  and 
viscosity  at  2250°  F.  The  clay  burned  to  a  dense  red  body.  Its  com- 
position is  as  follows: 

Analysis  of  the  under  Brick-clay  (No.  3),  Roanoke  Rapids. 

Moisture 2.05 

Silica   (total)    59.68 

Alumina    16.09 

Ferric  oxide   8.91 

Lime    1.35 

MagDesia    14 

Alkalies    3.24 

Water  (loss  on  ignition) 6.33 

/•  

Total    97.79 

Clay  substance  42.2S 

Free  sand  39.S2 

Total  fluxes 13.24 

Specific  gravity   2.56 

A  comparison  of  the  three  clays  sampled  from  this  locality  is  worth 
while.  The  last  two,  it  will  be  noticed,  possess  a  much  greater  plas- 
ticity than  the  first,  a  greater  tensile  strength,  and  burn  to  a  denser  and 
harder  body  at  the  same  temperature  than  the  first  one  does. 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  119 

The  under  bed  of  this  bank  is  far  better  suited  to  the  manufacture 
•of  good  brick  than  the  upper  sandy  one;  and  a  mixture  of  the  two 
would  be  better  than  using  either  the  upper  sandy  clay  alone  or  this 
with  sand  added.  The  latter  only  helps  to  make  the  brick  more  porous 
in  view  of  its  naturally  sandy  condition. 

Near  Weldon. — Similar  clays  to  those  at  Roanoke  Rapids  are  dug 
along  the  railroad  south  of  the  depot;  they  are  used  for  the  manufacture 
of  common  building  brick. 

Near  Halifax  also  there  are  extensive  beds  of  clay,  but  these,  like 
those  at  Weldon,  could  not  be  carefully  examined  in  time  for  the 
present  report. 

CLAY  IN  HARNETT   COUNTY. 

Near  Spout  Springs. — There  are  three  cuts  along  the  line  of  the 
C.  F.  &  Y.  V.  R.  R.  between  Fayetteville  and  Spout  Springs  in  which 
there  are  exposed  considerable  quantities  of  a  purplish  clay.  The  first 
of  these  is  between  the  92d  and  93d  mile  post,1  and  just  N.W.  of 
McClenehan  cut.  The  clay  comes  up  in  a  low,  dome-shaped  mass, 
showing  a  maximum  thickness  of  8  feet  above  the  roadbed.  There  is 
very  little  sand  covering,  and  the  clay  is  remarkably  homogeneous  in 
its  character.  An  examination  of  a  sample  from  this  cut  showed  it  to 
be  a  fine-grained,  tough  clay,  even  grained  and  with  conchoidal  frac- 
ture. It  slakes  easily  in  water  to  grains.  It  required  35$  of  water  to 
give  a  workable  paste  that  was  only  slightly  plastic  but  smooth.  This 
paste  shrank  10$  in  drying  and  4$  in  burning,  giving  a  total  shrinkage 
of  14$.  Air-dried  briquettes  made  from  this  paste  had  an  average  ten- 
sile strength  of  27  lbs.  per  square  inch  and  a  maximum  of  31  lbs.  per 
square  inch. 

Incipient  fusion  occurred  at  1950°  F.,  vitrification  at  2150°  F.,  and 
viscosity  at  2350°  F.  The  clay  burns  to  a  buff  at  2000°  F.,  but  with 
more  firing  turns  red.     The  composition  of  it  is  as  follows: 

Analysis  of  Brick-clay  {No.  16),  C.  F.  &  Y.  V.  R.  R.,  92-93  mile  post. 

Moisture    1.42 

Silica  (total) 64.16 

Alumina    -1.71 

Ferric  oxide  1.58 

Ferrous  oxide   1.08 

Lime    23 

Magnesia    1 5 

Alkalies    77 

Water  (loss  on  ignition)   8.30 

Total    99.40 

1  Measuring  from  Wilmington. 


£ 


120  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Clay  substance  58.55 

Free  sand   40.90 

Total  fluxes   3.81 

Specific  gravity    2.43 

The  second  cut  is  at  the  100-mile  post,  and  the  clay  shows  nine  feet 
of  thickness. 

Here,  again,  the  clay  (No.  17)  is  very  fine-grained  and  homogeneous, 
hut  not  quite  so  gritty  as  the  preceding.  It  slakes  just  the  same,  and 
required  32^  of  water  to  make  a  workable  but  rather  lean  paste,  which 
shrunk  8$  in  drying  and  6^  in  burning,  or  a  total  of  14=fc.  The  air-dried 
briquettes  had  an  average  tensile  strength  of  24  lbs.  per  square  inch  and 
a  maximum  of  29  lbs.  per  square  inch.  Incipient  fusion  occurred  at 
1950°  F.,  vitrification  at  2150°  F.,  and  viscosity  at  2350°  F.  The  clay 
burns  to  a  smooth,  red  body.     Its  composition  is: 

Analysis  of  Brick-clay  {No.  17),  C.  F.  &  Y.  V.  R,.  R.,  at  100  mile  pout. 

Moisture , 1.35 

Silica  (total) 50.68 

Alumina    32.51 

Ferric  oxide   3.06 

Lime 30 

Magnesia    02 

Alkalies    58 

Water  (loss  on  ignition)   11.08 

Total    99.58 

Clay   substance    83.43 

Free  sand   16.15 

Total  fluxes   3.96 

Specific  gravity    2.53 

The  third  cut  along  the  railroad  is  a  half  mile  southeast  of  Spout 
Springs  and  shows  fully  12  feet  of  this  clay;  while  a  fourth  exposure 
of  it  is  in  the  cut  just  northwest  of  Spout  Springs  station  (Plate  XII, 
fig.  2). 

The  clay  exposed  in  this  last  mentioned  cut  possesses  the  same  homo- 
geneous, tough,  fine-grained  character  as  those  just  described.  A  sample 
(Xo.  18)  tested  from  this  place  slaked  quickly  and,  when  mixed  with 
35$  of  water,  gave  a  workable,  lean,  smooth  mass  that  shrunk  9$  in 
drying  and  8^  in  burning,  a  total  shrinkage  of  17$.  The  air-dried, 
briquettes  made  from  this  paste  had  an  exceedingly  low  tensile  strength, 
19  lbs.  per  square  inch  on  the  average  with  a  maximum  of  25  lbs.  per 
square  inch.  Incipient  fusion  occurred  at  2000°  F.,  vitrification  at 
2200°  F.,  and  viscosity  at  2400°.  The  clay  burns  to  a  red-gray  dense 
body.     The  following  is  the  composition  of  this  clay: 


N.  C.  GEOLOGICAL  SURVEY. 


BULLETIN  13,  PLATE  XII. 


FIG.   1.— BRICKWORKS   OF  CARTER   AND  SHEPARD,    BETHANIA. 
(See  page  111.) 


FIG.   2.— CLAY    DEPOSIT   IN    RAILWAY   CUT,   SPOUT  SPRINGS,   C.  F.  &   Y.  V.   RAILROAD. 


*m 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  121 

Analysis  of  Clay  {No.  18),   C.  F.  &  Y.  V.  R.  R.,  Spout  Springs  station. 

Moisture 1.05 

Silica  (total)  53.65 

Alumina    28.66 

Ferric  oxide     4.50 

Lime    10 

Magnesia    1.35 

Alkalies     29 

Water  (loss  on  ignition)    10.79 

Total    100.39 

Clay  substance 73.77 

Free    sand    26.65 

Total  fluxes   6.24 

Specific   gravity    2.41 

CLAY  IN  JACKSON  COUNTY. 

^Tear  Sylva. — Along  the  road  south  of  Sylva  and  three-quarters  of  a 
mile  from  the  kaolin  washing  works  is  considerable  outcropping  of  gray 
clay  (No.  55)  with  much  quartz.  There  is  also  an  abundance  of  mica 
scales  in  it.  The  clay  which  has  been  experimented  with  in  the  hopes 
that  a  ball-clay  might  be  obtained  from  it  by  washing,  contains  too  much 
ferric  oxide.  Its  chief  application  lies  in  the  manufacture  of  pressed 
brick,  or  to  mix  with  a  more  plastic  clay  for  vitrified  wares,  such  as 
sewer-pipe  or  possibly  paving  brick. 

The  clay,  which  varies  from  coarse  to  fine,  contains  abundant  grains 
of  quartz  as  well  as  scales  of  mica.  It  slakes  slowly  to  irregular  grains. 
The  addition  of  2Sr/>  of  water  gave  a  tough  but  stiff  mass,  which  to  the 
feel  was  gritty  and  plastic.  The  shrinkage  in  drying  was  9$  and  in 
burning  5$,  giving  a  total  shrinkage  of  14^.  The  average  tensile 
strength  of  the  air-dried  briquettes  was  58  lbs.  per  square  inch,  with  a 
maximum  of  67  lbs.  Incipient  fusion  occurred  at  2100°  F.,  vitrifica- 
tion at  2300°  F.,  and  viscosity  at  2500°  F. 

The  clay  burns  red.     Its  composition  is  as  follows: 

Analysis  of  Brick-clay  {JSfo.  55),  near  Sylva. 

Moisture    45 

Silica  (total)    66.70 

Alumina    19.75 

Ferric  oxide   3.25 

Lime     45 

Magnesia    16 

Alkalies    2.12 

Water  (loss  on  ignition) 6.65 

Total    99.53 


122  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Clay  substance  47.28 

Free  sand  52.25 

Total  fluxes  6.08 

Specific  gravity   2.59 

CLAY  IN   MARTIN   COUNTY. 

Near  Williamston. — Two  samples  of  residual  clay  from  this  locality 
were  submitted  to  the  Geological  Survey  for  testing.  The  first  (No.  66) 
was  a  moderately  coarse-grained  clay  which  slaked  easily  to  irregular 
grains.  The  addition  of  40$  of  water  was  required  to  give  a  workable 
mass  that  to  the  feel  was  lean  and  gritty.  This  mud  shrunk  13$  in 
drying  and  3$  in  burning,  giving  a  total  shrinkage  of  16$.  Care  had 
to  be  .exercised  in  drying  to  prevent  it  from  cracking.  The  average 
tensile  strength  of  the  air-dried  briquettes  was  67  lbs.  per  square  inch, 
while  the  maximum  was  78  lbs.  Incipient  fusion  occurs  at  2000°  F.. 
vitrification  at  2150°  F.,  and  viscosity  at  2300 =  F.  The  clay  burns 
red  at  incipient  fusion,  but  above  that  the  color  deepens  rapidly. 

The  second  sample  was  similar  in  appearance  to  the  first  one,  and, 
like  it,  slaked  easily  to  its  component  grains.  The  addition  of  29$  of 
water  gave  a  workable  but  lean,  sticky  mass,  which  shrunk  10$  in  dry- 
ing and  2$  in  burning,  giving  a  total  shrinkage  of  12$.  The  air-dried 
briquettes  had  an  average  tensile  strength  of  71  lbs.  per  square  inch 
with  a  maximum  of  100  lbs.  Incipient  fusion  occurred  at  2000°  F., 
vitrification  at  2150°  F.,  and  viscosity  at  2200°  F. 

The  clay  burns  red  at  2000°  F.,  but  the  color  becomes  much  deeper 
with  harder  firing. 

This  clay  cracks  less  than  the  previous  one  in  drying,  for  the  shrink- 
age is  less. 

Both  these  clays  illustrate  the  lean  character  and  low-binding  quali- 
ties of  some  clays,  both  sedimentary  and  residual.  Their  porous 
nature  and  avidity  for  water  cause  them  to  soak  up  large  quantities  of  it, 
and  the  consequent  expulsion  of  this  water  brings  about  excessive  shrink- 
age and  necessitates  very  slow  drying.  The  only  remedy  in  such  cases 
is  the  admixture  with  these  lean,  porous  clays  of  other  clays  that  are 
more  compact  and  have  better  binding  qualities. 

CLAY   IN   MECKLENBURG    COUNTY. 

Near  Charlotte. — The  region  in  the  vicinity  of  Charlotte  is  under- 
lain by  sedimentary  clays  in  the  hollows,  and  residual  clays  on  the 
hills.  While  those  in  the  hollows  are  largely  composed  of  the  wash 
from  the  hills,  still,  on  account  of  the  sorting  and  elimination  of  coarse 
particles  which  follow  as  a  result  of  the  washing,  the  lowland  deposits 
are  smoother  and  more  plastic. 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  123 

One  of  the  latter  class  is  near  D.  K.  Cecil's  yard  on  Trade  street  at 
the  east  edge  of  the  town. 

The  section  of  this  clay  bank  shows  the  following: 


Loam    (soil)   12-18  inches. 

Clay   8  feet. 

Sand    

The  clay  is  gray,  mottled  with  iron  stains,  fine-grained,  fairly  smooth. 
There  is  no  mica  apparent.     It  slakes  quickly. 

The  addition  of  25.8^  of  water  gave  a  moderately  plastic  paste  with 
somewhat  gritty  feel.  This  paste  shrunk  Qfo  in  drying  and  6$  in  burn- 
ing, giving  a  total  shrinkage  of  12$.  The  average  tensile  strength  of 
air-dried  briquettes  was  88  lbs.  per  square  inch  with  a  maximum 
strength  of  95  lbs.  per  square  inch. 

Incipient  fusion  occurs  at  1850°  F.,  vitrification  at  2050°  F.,  and 
viscosity  at  2250°  F. 

The  clay  burns  to  a  red,  fairly  smooth  body.  Its  composition  is  as 
follows : 

Analysis  of  B.  K.  Cecil's  Brick- clay  (N~o.  39),  Charlotte. 

Moisture    1.35 

Silica    (total)    68.35 

Alumina 13.13 

Ferric   oxide    6.87 

Lime 2.10 

Magnesia    32 

Alkalies    2.86 

Water  (loss  on  ignition)  5.20 

Total    100.18 

Clay  substance  38.73 

Free  sand   61.45 

Total  fluxes   12.15 

Specific  gravity    2.68 

Mr.  Cecil  uses  the  clay  for  the  manufacture  of  common  brick.  The 
clay  is  molded  in  an  auger  side-cut  machine,  dried  on  pallets  and  burned 
in  scove  kilns.     The  product  is  usually  a  hard,  dense  brick. 

At  Houser's  yard,  one-quarter  mile  from  Cecil's,  there  is  a  similar 
deposit  of  sedimentary  clay.  It  contains  an  abundance  of  small  quartz 
grains.  The  bricks  are  barely  burned  to  incipient  fusion.  Houser's 
plant  includes  a  pair  of  rolls,  Brewer  side-cut  machine,  and  pallet  racks. 

The  clay  from  this  yard  was  not  tested.  It  is  situated  along  the 
same  stream  as  Cecil's  deposit. 

At  F.  M.  Sassamon's  brickyard,  two  miles  northwest  of  Charlotte, 


121  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

the  clay  lies  in  a  hollow  and  covers  a  number  of  acres.  Its  exact  thick- 
ness is  not  known,  but  it  is  not  less  than  six  feet.  A  sample  of  this  clay 
was  examined  and  found  to  be  a  somewhat  coarse-grained,  porons  clay. 
It  slakes  moderately  fast  to  fine  aluminous  mud  and  granules.  The 
addition  of  35fc>  of  water  gave  a  plastic  mass,  which  shrunk  13.3$  in 
drying  and  8fo  in  burning,  giving  a  total  shrinkage  of  21.3$.  The  dry- 
ing could  not  be  hurried,  as  otherwise  cracking  resulted.  The  average 
tensile  strength  of  the  air-dried  briquettes  was  105  lbs.  per  square  inch 
with  a  maximum  of  125  lbs. 

Incipient  fusion  occurred  at  1950°  F.,  vitrification  at  2100'  I\,  and 
viscosity  at  2250°  F.     The  clay  burns  red. 

Its  composition  is  as  follows: 

Analysis  of  F.  M.  Sassamon's  Brick  clay  (Wo   42).  Charlotte. 

Moisture    1.27 

Silica    (total)    » . 65.95 

Alumina    14.67 

Ferric  oxide 7.61 

Lime    2.57 

Magnesia    25 

Alkalies    2.55 

Water  (loss  on  ignition)  5.52 

Total    100.39 

Clay  substance  43.84 

Free  sand   56.45 

Fluxes 12.98 

Specific  gravity    2.60 

Shuman  operates  a  deposit  (No.  11)  just  north  of  Charlotte,  which  is 
a  mixture  of  sedimentary  clay  and  residuum.  It  is  about  9  feet  thick 
as  exposed,  and  varies  from  a  sandy  clay  to  a  fat,  tough  one. 

Most  of  it  is  coarse-grained,  gritty,  and  slakes  slowly  but  completely. 
The  clay  required  the  addition  of  35$  of  water  to  give  a  workable, 
though  lean  mass.  Its  porous  nature  permitted  rapid  drying,  and  it 
shrunk  5$  in  doing  so.  The  shrinkage  in  burning  was  4$,  giving  a 
total  shrinkage  of  9$.  Air-dried  briquettes  had  an  average  tensile 
strength  of  26  lbs.  per  square  inch  and  a  maximum  of  2S  lbs.  Incipi- 
ent fusion  occurred  at  2100°  F.,  vitrification  at  2200°  T.,  and  viscosity 
at  2300°  F.     The  clay  burns  to  a  reddish  brick. 

The  composition  of  it  is  as  follows: 

Analysis  of  F.  W.  Shuman' s  Brick-clay  (No.  41),  Charlotte. 

Moisture    7.10 

Silica    59.15 

Alumina    18.36 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  125 

Ferric  oxide  6.04 

Lime    20 

Magnesia     34 

Alkalies    1.72 

Water  (loss  on  ignition)  7.47 

Total    100.38 

Free  sand    39.50 

Total  fluxes   8.30 

Specific  gravity    2.44 

J.  Asbury  lias  a  brickyard  about  one  and  a  half  miles  north  of  the 
town.  The  section  at  the  clay  bank  shows  four  feet  of  red  clay  (sample 
No.  62)  and  under  this  six  feet  of  very  plastic  blue  clay.  The  addition 
of  25$  of  water  gave  a  workable  paste  of  good  plasticity. 

This  paste  shrank  7$  in  drying  and  5$  in  burning.  The  average 
tensile  strength  of  the  air-dried  briquettes  was  60  lbs.  per  square  inch 
with  a  maximum  of  72  lbs.  per  square  inch.  Incipient  fusion  occurred 
at  1900°  F.,  vitrification  at  2100°  F.,  and  viscosity  at  2300°  F. 

The  clay  burns  red.     Its  analysis  shows  the  following: 

Analysis  of  J.  Asbury's  upper  red  Brick-clay  (No.  62),  Charlotte. 

Moisture    63 

Silica  (total)  60.33 

Alumina    18.57 

Ferric  oxide 10.03 

Lime    20 

Magnesia    14 

Alkalies    55 

Water  (loss  on  ignition)   7,83 

Total    98.28 

Clay    substance    56.23 

Free  sand  42.05 

Total  fluxes   10.02 

Specific   gravity    2.60 

CLAY    IN    RICHMOND    COUNTY. 

Near  Rockingham. — A  red,  coarse-grained,  sedimentary  clay  (Xo. 
23)  occurs  at  Roberdell,  four  miles  north  of  Rockingham.  The  upper 
portion  of  the  deposit  is  somewhat  sandy.  In  practice  the  bricks  seem 
to  shrink  considerably  in  burning  and  also  to  crack,  but  they  burn  to 
a  deep  red  color.     The  clejDosit  is  owned  by  R.  L.  Steele. 

A  sample  of  this  clay  slaked  slowly  to  grains  ?V  to  T\T  in.  diameter. 
It  required  26$  of  water  to  make  a  workable  paste  which  shrunk  CVr 
in  drying  and  8$  in  burning,  making  a  total  shrinkage  of  14$.  It 
required  slow  heating  to  avoid  cracking.      The  average  tensile  strength 


126  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

of  air-dried  briquettes  made  from  this  paste  was  133  lbs.  per  square 
inch  with  a  maximum  of  154  lbs.  Incipient  fusion  occurs  at  2000°  F., 
vitrification  at  2200°  F.,  viscosity  at  2400°  F.  The  clay  bums  to  a  deep 
red.  It  is  not  fine  or  smooth  enough  to  be  used  for  pottery.  The 
composition  of  the  clay  is  as  follows: 

Analysis  of  Brick  clay  {No.  23),  4  miles  N.  of  Rockingham. 

Moisture 1.98 

Silica  (total)  59.59 

Alumina    22.07 

Ferric  oxide  4.27 

Lime   65 

Magnesia    49 

Alkalies    2.70 

Water  (loss  on  ignition)  7.53 

Total    99.28 

Clay  substance 51.63 

Free  sand    47.65 

Fluxes   8.11 

Specific  gravity   2.54 

CLAY   IN   ROBESON   COUNTY. 

^Near  Red  Springs. — Five  or  six  brickyards  have  been  in  operation 
at  this  locality  for  some  years.  The  flat,  wooded  region  around  the 
town  is  underlain  by  abundance  of  yellowish,  coarse-grained,  sandy  clay 
of  extreme  leanness.  The  abundant  sand  grains  are  nearly  all  pure 
quartz. 

The  poor  quality  of  this  material  is  evident  on  sight,  but  a  sample 
(No.  19)  was  tested  in  order  to  demonstrate  this  fact,  for  there  is  a 
tendency  among  many  small  manufacturers  to  use  very  sandy  clay,  as  it 
molds  easier. 

The  examination  showed  it  to  be  a  porous,  coarse  clay,  slaking  fairly 
fast  in  water.  It  required  17$  of  water  to  make  a  workable  mass 
which  was  extremely  lean.  This  paste  shrank  8.8$  in  drying  and  4$ 
in  burning,  giving  a  total  shrinkage  of  12.8$.  Air-dried  briquettes 
had  an  average  tensile  strength  of  41  lbs.  per  square  inch  and  a  max- 
imum of  51  lbs.  Incipient  fusion  occurred  at  2100°  F.,  vitrification  at 
2250°  F.,  viscosity  at  2400°  F.  At  2100°  F.  it  burns  red,  but  is  still 
porous  and  weak. 

The  composition  of  the  clay  is  as  follows: 

Analysis  of  Brick-clay  {No.  19),  Red  Springs. 

Moisture    1.09 

Silica  (total)   78.16 

Alumina    8.26 

Ferric  oxide 4.09 

Lime    40 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  127 

Magnesia    22 

Alkalies    2.91 

Water  (loss  on  ignition)    4.14 

Total    99.27 

Clay  substance   15.22 

Free  sand  74.05 

Total  fluxes   7.62 

Specific  gravity   2.60 

The  chemical  analysis  indicates  the  large  percentage  of  sand  in  the 
clay,  and  the  quantity  and  coarseness  of  this  sand  makes  the  clay  too 
lean.  On  account  of  this  very  high  percentage  of  sand  in  the  clay 
considerable  heat  is  required  to  make  a  hard  brick  of  it. 

None  of  the  clay  pits  at  Red  Springs  are  deep,  and  it  is  not  known 
whether  the  clay  increases  with  depth,  but  if  it  does  the  product  would 
be  of  much  better  quality  by  using  it. 

CLAY   IN    ROWAN    COUNTY. 

Near  Salisbury. — Half  a  mile  south  of  the  station  is  an  area  of 
swamp  land  underlain  by  considerable  clay,  mostly  of  a  plastic  nature. 

The  section  shows  6  feet  of  clay  underlain  by  sand,  and  the  tract  is 
about  an  eighth  of  a  mile  long.  There  are  occasional  iron  streaks  in 
the  clay,  but  these  are  mostly  confined  to  sandy  spots.  A  sample  of 
this  clay  (No.  48)  which  was  tested  showed  it  to  be  medium-grained 
with  considerable  grittiness.  It  slaked  slowly  and  required  the  addi- 
tion of  28$  of  water  to  give  a  workable  mixture  which  was  very  plastic. 
This  mass  shrunk  8.5$  in  drying  and  5.5$  in  burning,  giving  a  total 
shrinkage  of  14$.  The  average  tensile  strength  of  air-dried  briquettes 
was  129  lbs.  per  square  inch  with  a  maximum  of  144  lbs.  Incipient 
fusion  occurs  at  1850°  F.,  vitrification  at  2050°  F.,  and  viscosity  at 
2250°  F. 

The  clay  burns  to  a  red  color.     Its  composition  is  as  follows: 

Analysis  of  Brick-clay  {No.  48),  south  side  of  Salisbury. 

Moisture    1.91 

Silica  (total)   69.89 

Alumina    15.31 

Ferric  oxide   4.39 

Lime   55 

Magnesia    16 

Alkalies .     .70 

Water  (loss  on  ignition)  6.37 

Total 99.2S 

Clay    substance    47.3S 

Free  sand 51.90 

Total  fluxes   5.80 


128  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

This  clay  has  been  used  at  D.  K.  Cecil's  brickyard  for  five  years. 
The  clay  receives  no  tempering,  but  is  charged  directly  into  a  small 
auger  machine  with  a  three-stream  die.  The  bricks  are  dried  in  the 
sun  and  burned  in  scove  kilns. 

The  quality  of  the  brick  admits  of  much  improvement,  and  the 
quality  of  the  clay  warrants  it. 

CLAY   IN    SURRY    COUNTY. 

!Neae  Elkin. — An  opening  has  been  made  one  mile  west  of  town 
along  the  railroad  and  on  the  property  of  the  Pomona  SeAver-pipe  Co., 
and  exposes  the  same  yellowish  clay  as  that  noted  at  \Yilkesboro.  The 
clay  is  8-10  feet  deep  and  underlain  by  sand  and  coarse  pebbles. 

The  clay  itself  (No.  38a)  is  fine-grained  and  contains  numerous  small 
mica  scales  and  fine  grit.  It  slakes  somewhat  slowly  to  its  component 
grains.  The  addition  of  16$  of  water  gave  a  workable  but  somewhat 
lean  mud,  which  shrank  7$  in  drying  and  9$  in  burning.  The  average 
tensile  strength  of  the  air-dried  briquettes  was  69  lbs.  per  square  inch 
and  the  maximum  was  73  lbs. 

Incipient  fusion  occurred  at  1900°  E.,  vitrification  at  2100°  E.,  vis- 
cosity at  2300°  1".  The  clay  burns  red  and  gets  very  deep  red  or 
brown  on  vitrifying. 

The  analysis  of  it  yielded  the  following: 

Analysis  of  Brick-clay  (No.  38a),  Pomona  Co.'s  bank,  FAkin. 

Moisture    90 

Silica  (total)   59.4S 

Alumina    19.24 

Ferric  oxide 8.26 

Lime     60 

Magnesia    1.01 

Alkalies     3.76 

Water  (loss  on  ignition) 6.41 

Total    99.66 

Clay  substance   49.21 

Free  sand   50.35 

Total  fluxes   13.53 

Specific  gravity    2.59 

Mixed  with  some  more  plastic  clay,  such  as  that  used  for  sewer-pipe 
at  Pomona,  this  clay  might  possibly  be  used  for  the  manufacture  of 
paving  brick. 

There  are  numerous  points  between  Elkin  and  ISTorth  ^Yilkesboro 
where  the  cutting  of  gullies  in  the  terrace  has  exposed  this  yellow  clay. 

The  clay  used  at  the  brickyards  just  east  and  west  of  Elkin  is  resid- 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  129 

ual  material  of  uncertain  character  and  not  associated  with  that  down 
in  the  valley  bottom. 

"While  these  yellow  clays  of  the  lowlands  would  doubtless  make  a 
good  smooth  building  brick  by  the  soft-mud  process,  it  is  doubtful  if 
they  would  work  in  an  auger  machine,  and  probably  refuse  to  issue 
from  the  die  without  tearing,  for  there  is  little  bond  between  the  clay 
particles.  In  mixing,  it  also  shows  slight  tendency  by  itself  towards 
the  development  of  a  laminated  structure. 

CLAY   IN    UNION   COUNTY. 

Near  Monroe. — The  lowlands  southwest  of  the  depot  are  underlain 
by  an  abundance  of  blue  clay,  and  though  only  about  6  feet  deep, 
still  it  covers  a  considerable  area.  As  the  creek  which  flows  through  the 
lowland  is  approached  the  clay  becomes  more  sandy. 

A  sample  of  this  clay  (No.  40)  was  found  to  be  fairly  smooth  and 
slaked  slowly  but  rather  completely.  It  required  the  addition  of  23$ 
of  water  to  produce  a  workable  mass  that  was  very  plastic  and  that 
shrank  6$  in  drying  and  3$  in  burning,  giving  a  total  shrinkage  of  9$. 
Incipient  fusion  occurred  at  1950°  F.,  vitrification  at  2150°  F.,  and 
viscosity  at  2350°  F.  The  clay  burns  red,  but  underburning  produces 
a  yellowish  red. 

For  a  plastic  clay  the  shrinkage  is  quite  low. 

The  average  tensile  strength  of  the  air-dried  briquettes  was  124  lbs. 
per  square  inch  with  a  maximum  of  148  lbs.  per  square  inch. 

It  is  probable  that  some  of  the  finer  portions  of  this  clay  bed  could  be 
used  for  the  lower  grades  of  stoneware. 

The  composition  of  the  clay  is  as  follows,  the  sample  (No.  40)  coining 
from  J.  T.  Shute's  clay  bank: 

Analysis  of  Brick-clay  {No.  40),  Shute's  clay  bank,  Monroe. 

Moisture    1.65 

Silica  (total) 76.60 

Alumina    9.98 

Ferric  oxide 4.46 

Lime   30 

Magnesia    27 

Alkalies-   2.25 

Water  (loss  on  ignition)   4.30 

Total    99.81 

Clay    substance    34.26 

Free  sand  65.55 

Total  fluxes  7.28 

The  clay  contains  a  small  amount  of  organic  matter  and  is  a  good 
illustration  of  the  combination  of  low  alumina  and  marked  plasticity. 
9 


130  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

J.  T.  Shute  manufactures  common  brick  from  the  clay  at  Monroe. 
The  clay  makes  a  very  fair  product,  but  has  to  be  burned  carefully. 

The  bricks  are  molded  in  a  Brewer  auger  machine  with  vertical  pug- 
ging cylinder  attached. 

CLAY   IN   WAKE    COUNTY. 

Near  Raleigh. — Much  clay  of  very  plastic  nature  underlies  the 
bottom  lands  north  and  east  of  the  city.  It  has  thus  far  been  worked 
only  for  building  brick,  although  promising  experiments  have  been 
made  looking  towards  its  utilization  for  the  coarser  grades  of  pottery. 
A  small  deposit  of  considerable  plasticity  underlies  the  low  ground 
between  Caraleigh  Mills  and  the  phosphate  mill  southeast  of  town. 
This  deposit  is  not  nearly  so  extensive,  however,  as  that  north  of  the 
town  in  the  lowland  along  the  Neuse  river. 

The  clay  used  at  the  penitentiary  is  obtained  from  the  lowland 
southeast  of  the  city.  The  upper  two  feet  are  a  yellowish  sandy  clay, 
but  under  this  is  a  much  fatter  gray  clay  possessing  considerable  plas- 
ticity to  the  feel,  and  frequently  comparatively  free  from  grit  in  the 
form  of  coarse  sand  grains.  A  small  amount  of  organic  matter  is 
present.  It  is  a  tough,  fairly  compact  clay  which  slakes  rather  fast  to 
grains  and  granules.  It  required  the  addition  of  25$  of  water  to  make  a 
workable  mass,  which  shrunk  9.3$  in  drying  and  4$  in  burning,  giving  a 
total  shrinkage  of  13.3$.  Air-dried  briquettes  made  from  this  mixture 
had  an  average  tensile  strength  of  123  lbs.  per  square  inch  and  a  max- 
imum tensile  strength  of  144  lbs.  per  square  inch.  Incipient  fusion 
occurred  at  2000°  F.,  vitrification  at  2150°  F.,  and  viscosity  at  2300°  F. 
The  clay  burns  to  a  red,  which  increases  in  depth  of  color  when  the 
clay  is  burned  to  vitrification.  The  composition  of  this  clay  is  shown 
by  the  following: 

Analysis  of  Brick-clay  {No.  23),  Penitentiary  Yard,  Raleigh. 

Moisture    1.60 

Silica  (total)    70.03 

Alumina    15.64 

Ferric  oxide 2.SS 

Lime    80 

Magnesia   57 

Alkalies    1.47 

Water  (loss  on  ignition) 6.37 

Total 99.36 

Free  sand 54.55 

Clay  substance    44. SI 

Total   fluxes    5.72 

Specific  gravity    2.54 


. 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  131 

The  low  percentage  of  total  fluxes  accounts  partly  for  the  fusion 
point  being  2300°. 

It  is  probable  that  some  of  the  smoother  portions  of  this  clay  deposit 
would  work  very  well  for  common  stoneware. 

The  clay  underlying  A.  Ii.  Green's  land  on  the  north  side  of  the 
river  is  less  gritty. 

The  clay-working  industry  around  Raleigh  is  confined  to  the  manu- 
facture of  common  brick.  These  are  made  by  the  Caraleigh  Mills 
Company  and  the  North  Carolina  State  Penitentiary.  Both  used  hand- 
molds  and  dry  the  bricks  in  the  sun  and  burn  them  in  up-draft,  open- 
top  kilns.  Considering  the  method  of  molding,  the  clay  makes  a  very 
good  red  building  brick.  Steam-power  machinery  would  no  doubt 
greatly  increase  the  value  of  the  product.  Re-pressing  has  been  tried 
with  considerable  success,  and  brick  thus  treated  were  used  in  the  gov- 
ernor's mansion  at  Raleigh. 

CLAY   IN    WAYNE    COUNTY. 

!STear  Goldsboro. — There  are  extensive  beds  of  sedimentary  clay 
underlying  the  lowlands  southeast  of  the  town.  At  the  Goldsboro  Brick 
and  Tile  Company,  or  Grant's  yard,  one  mile  southwest  of  Goldsboro, 
quite  a  large  surface  has  been  worked  over  in  obtaining  its  clay,  in  order 
to  use  the  clay  at  the  surface,  which  is  far  more  sandy  but  of  good  plas- 
ticity.    The  exact  depth  of  the  clay  is  not  known. 

A  track  runs  along  the  central  portion  of  the  excavation,  and  the  clay 
is  dug  by  means  of  scrapers  and  brought  to  cars  on  the  track.  These 
cars  are  hauled  to  the  foot  of  an  incline  and  drawn  up  by  cable  to  the 
second  floor  of  the  works,  where  the  clay  is  discharged.  It  passes  first 
through  a  pair  of  rolls  and  then  to  the  pugmill,  from  which  it  is  dis- 
charged into  a  Kell's  auger  machine.  The  brick  are  side-cut,  and  the 
cutting  table  is  operated  by  hand  power.  Ten  brick  are  cut  at  a  time 
and  discharged  from  the  cutting  table  on  to  a  pallet.  The  bricks  are 
carried  directly  to  the  drying  chambers.  These  consist  of  a  series  of 
cupboards,  across  which  runs  a  series  of  parallel  steam-pipes,  which 
serve  as  a  shelving.  The  pallets  are  shoved  endwise  into  each  cham- 
ber. In  the  practice  of  this  method  a  considerable  per  cent,  of  the 
brick  may  be  lost  when,  in  pushing  the  pallet  into  the  chamber,  the 
"  off-bearer "  pushes  against  the  end  brick  instead  of  the  pallet  and 
crushes  the  former  all  out  of  shape.  The  drying  requires  three  days 
when  heat  is  applied  during  the  daytime  only.  The  yard  is  also 
equipped  with  pallet  racks. 

Burning  is  done  in  up-draft  kilns  with  a  capacity  of  about  200,000 
each.     The  bricks  are  burned  to  a  light  red. 

The  upper  part  of  the  clay  consists  of  tough,  light-blue  plastic  clay 


132  CLAY    DEPOSITS    IX    NORTH    CAROLINA. 

with  much  intermixed  sand.  The  use  of  the  rolls  is  supposed  to  break 
up  these  lighter-colored  lumps  of  clay,  but  it  does  not  always  do  so 
entirely,  as  can  be  seen  from  an  inspection  of  the  burned  brick,  the 
lighter-colored  lumps  of  the  clay  occasionally  showing  within.  A  wet 
pan  would  probably  give  better  results.  The  mixture  of  the  sandy  and 
tough  clay  gives  the  best  results  and  makes  a  good  brick. 

A  sample  of  this  clay  was  tested.  It  was  a  coarse  to  fine-grained 
clay  (No.  7)  that  slaked  irregularly.  The  addition  of  33  per  cent, 
of  water  gave  a  fairly  plastic  and  somewhat  tough  mass,  which  shrunk 
8$  in  drying  and  6$  in  burning,  giving  a  total  shrinkage  of  14X  The 
air-dried  briquettes  had  an  average  tensile  strength  of  65  lbs.  per  square 
inch  and  a  maximum  tensile  strength  of  74  lbs.  per  square  inch.  Incipi- 
ent fusion  occurs  at  1900°  F.,  vitrification  at  2100°  T.,  and  viscosity  at 
2300°  F. 

This  kind  of  clay  should  be  thoroughly  mixed,  and  when  so  treated 
it  burns  to  a  uniform  attractive  red,  but  if  the  clay  be  not  well  mixed 
the  lumps  of  tougher  clay  are  plainly  seen  if  the  temperature  is  raised 
rapidly  so  that  the  iron  in  them  does  not  get  a  chance  to  become  thor- 
oughly oxidized.     The  composition  of  this  clay  mixture  is  as  follows: 

Analysis  of  Gt  ant's  Brick-zlay  (No.  7),  Goldsboro. 

Moisture    1.58 

Silica  (total)    66.05 

Alumina    17.81 

Ferric  oxide  6.69 

Lime    30 

Magnesia   25 

Alkalies     1.04 

Water  (loss  on  ignition)   6.32 

Total    100.04 

Clay  substance  51.47 

Total  fluxes 7.76 

Free  sand  48.05 

Specific  gravity   2.53 

Near  the  factory  of  the  Goldsboro  Brick  and  Tile  Company  is  a  con- 
siderable quantity  of  tough  clay  which  is  called  "  fire-clay,"  but  which 
is  not  a  true  fire-clay  as  that  term  is  generally  used.  This  clay  simply 
requires  a  little  more  heat  in  burning  the  brick  than  the  clay  usually 
employed. 

A  sample  of  this  "  fire-clay  "  showed  it  to  be  a  tough,  plastic,  fine- 
grained clay  with  scattered  scales  of  mica,  It  slakes  moderately  fast 
to  a  mixture  of  fine  powder  and  small  angular  quartz  grains.  The  addi- 
tion of  25$  of  water  gave  a  plastic,  workable  paste  that  shrunk  8.5$  in 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  133 

drying  and  an  additional  5$  in  burning,  giving  a  total  shrinkage  of 
13.5$.  The  air-dried  briquettes  made  from  this  paste  had  an  average 
tensile  strength  of  107  lbs.  per  square  inch  and  a  maximum  of  125  lbs. 
per  square  inch.  Incipient  fusion  occurs  at  1950°  F.,  vitrification  at 
2150°  F.,  and  viscosity  at  2300°  F.  The  clay  burns  to  a  deep  red, 
tough,  dense  body,  and  might  be  worked  for  stoneware. 
The  following  analysis  shows  its  composition: 

Analysis  of  Grant's  "  Fire-clay  "   (No.  9),  Goldsboro. 

Moisture    1.12 

Silica  (total)    65.95 

Alumina    13.51 

Ferric  oxide 4.64 

Lime   35 

Magnesia 36 

Alkalies    2.82 

Water  (loss  on  ignition)   11.58 

Total     100.33 

Clay  substance  49.63 

Total  fluxes  8.17 

Free  sand 50.70 

Specific  gravity   , .• 2.55 

On  account  of  the  high  percentage  of  combined  water  the  clay  had  to 
be  heated  very  slowly  to  prevent  cracking. 

II.  Weil  &  Bros.7  yard  and  clay  bank  are  about  a  mile  and  a  half 
southwest  of  Goldsboro.  Their  clay  deposit,  which  is  an  extension  of 
that  of  the  Goldsboro  Brick  &  Tile  Co.,  contains  a  considerable  quan- 
tity of  plastic  clay.  This  is  8  feet  thick  in  places,  and  towards  the 
surface  becomes  mixed  with  sand.  The  clay  is  molded  by  hand  and 
pugged  in  a  vertical  mill  operated  by  horse-power.  The  water-smoking 
and  burning  is  done  in  the  rather  short  time  of  five  days. 

A  sample  of  the  plastic  clay  (No.  8)  tested  showed  it  to  be  moder- 
ately fine  with  considerable  grit  and  mica  scales.  The  clay  is  some- 
what porous  but  tough,  and  slakes  slowly  to  irregular  grains.  The 
addition  of  25$  of  water  gave  a  workable  mixture  of  fair  plasticity.  It 
shrunk  8.3$  in  drying  and  3$  in  burning,  giving  a  total  shrinkage  of 
11.3$.  The  air-dried  briquettes  made  from  the  worked-up  paste  had 
an  average  tensile  strength  of  85  lbs.  per  square  inch  and  a  maximum 
strength  of  102  lbs.  per  square  inch.  Incipient  fusion  occurs  at  1900° 
F.,  vitrification  at  2100°  F.,  and  viscosity  at  2300°  F. 

The  clay  burns  to  a  red  color.  Underburning  and  imperfect  oxida- 
tion make  the  brick  grayish-red  or  brown,  and  porous. 

The  composition  of  the  clay  is  as  follows: 


134  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Analysis  of  Weil's  Brick-clay  (No.  8),  Ooldsboro. 

Moisture    1.85 

Silica  (total)    67.90 

Alumina    18.74 

Ferric  oxide 3.1G 

Lime    40 

Magnesia 45 

Alkalies   1.85 

Water  (loss  on  ignition)  6.03 

Total    100.38 

Clay  substance  46.23 

Total  fluxes  5.86 

Free  sand  54.15 

Specific  gravity    2.57 

CLAY   IN    WILKES    COUNTY. 

Near  Wilkesboro. — The  valley  of  the  Yadkin  river  at  this  locality 
is  nearly  three-quarters  of  a  mile  wide,  and  its  broad,  flat  bottom  is 
underlain  by  an  abundance  of  clay. 

At  D.  SmoaWs  yard,  on  the  south  side  of  the  river  just  west  of  the 
iron  bridge,  the  clay  is  said  to  be  13  feet  thick  and  to  be  underlain  by 
gravel  and  sand.  As  the  river  is  approached,  the  surface  sand  increases 
in  depth.  The  clay  is  claimed  to  improve  greatly  with  the  depth,  so 
a  sample  (No.  37)  was  taken  from  the  bottom  of  the  deposit  and  one 
(No.  36)  representing  the  average  material  now  used. 

The  latter  (No.  36)  is  a  fine-grained,  yellowish  clay  with  numerous 
very  small  mica  scales.  It  slakes  quite  rapidly  and  completely  to  fine 
grains.  The  addition  of  25^  of  water  gave  a  workable  but  lean  paste. 
This  paste  shrunk  5^  in  drying  and  10$  in  burning,  giving  a  total 
shrinkage  of  15$.  The  average  tensile  strength  of  the  air-dried  bri- 
quettes was  74  lbs.  per  square  inch  with  a  maximum  of  76  lbs.  per 
square  inch. 

Incipient  fusion  occurs  at  1900°  F.,  vitrification  at  2100°  F.,  and 
viscosity  at  2300°  F. 

At  2100°  the  clay  burns  to  a  good  red,  but  above  this  temperature  it 
darkens  rapidly. 

The  composition  of  this  clay  is  as  follows: 

Analysis  of  Smoak's  Brick-clay  {No.  36),    Wilkesboro. 

Moisture    1.03 

Silica  (total)    53.75 

Alumina    24.01 

Ferric  oxide   7.00 

Lime    70 

Magnesia    1.12 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  135 

Alkalies    . 2.94 

Water  (loss  on  ignition) 7.60 

Total    100.04 

Clay  substance    54.04 

Total  fluxes    12.75 

Free  sand  46.00 

Specific  gravity    2.G3 


The  bottom  clay  (No.  37)  at  Smoak's  brickyard  is  also  a  fine-grained, 
yellowish-brown  clay  with  abundant  fine  grit  and  small  mica  scales. 
It  slakes  rather  quickly  and  completely  to  its  component  grains.  The 
clay  required  24$  of  water  to  make  a  workable  paste,  which  was  some- 
what lean. 

This  paste  shrunk  6$  in  drying  and  9$  in  burning,  giving  a  total 
shrinkage  of  15$.  The  average  tensile  strength  of  the  air-dried  bri- 
quettes was  71  lbs.  per  square  inch  with  a  maximum  of  84  lbs. 

Incipient  fusion  occurred  at  1900°  F.,  vitrification  at  2100°  F.,  and 
viscosity  at  2300°  F. 

The  clay  burns  to  a  bright  red  at  1900°  F.,  but  this  rapidly  darkens 
as  the  temperature  is  raised. 

The  physical  characters  of  this  clay  are  therefore  closely  similar  to 
that  composing  upper  portions  of  the  deposit. 

The  composition  of  this  lower  clay  is  as  follows: 

Analysis  of  Smoak's  bottom  Brick-clay  (No.  37),    Wilkesboro. 

Moisture    2.10 

Silica   (total)    52.25 

Alumina    20.66 

Ferric  oxide 11.14 

Lime    60 

Magnesia    1.08 

Alkalies    4.62 

Water  (loss  on  ignition)  7.45 

Total    99.90 

Clay  substance  57.45 

Total  fluxes 17.44 

Free  sand  42.45 

Specific   gravity    2.44 

In  fluxes  this  bottom  clay  runs  several  per  cent,  higher  than  the  top 
and  contains  less  alumina. 

This  clay  and  the  preceding  one  described  underlie  the  same  terrace 
as  does  the  pottery  clay  on  the  Calvin  Cowles  land,  the  two  being  not 
more  than  half  a  mile  apart  (see  p.  79). 


136  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Mr.  Smoak  uses  the  yellowish  clay  for  the  manufacture  of  common 
brick.  It  is  molded  by  hand,  dried  in  the  sun  and  burned  in  up-draft, 
permanent  side-wall  kilns.  The  clay  makes  a  good  brick,  and  also 
yields  promising  results  with  re-pressing.  Some  of  the  re-pressed  brick 
are  to  be  seen  in  the  bank  building  at  Xorth  Wilkesboro. 

CLAY   IN   WILSON   COUNTY. 

Near  Wilson. — Sedimentary  clay  occurs  in  considerable  quantity  on 
the  east  and  northeastern  edge  of  the  town  and  is  extensively  worked. 
The  A.  C.  L.  E.  K.  passes  close  to  the  deposits.  At  S.  Lucas's  yard, 
northeast  of  the  town  along  the  railroad,  the  section  is  as  f oIIoavs  : 

Sandy  soil 1  ft. 

Sand,  clayey  in  spots 2  ft. 

Sandy  clay,  red 3  ft. 

Blue  clay  3  ft.  -f 

The  sandy  soil  is  stripped  and  a  mixture  of  the  remaining  portion  of 
the  section  used.  Two  openings  have  been  made  which  show  similar 
sections,  but  the  clay  in  the  southern  one  is  red  while  that  in  the  north- 
ern one  is  blue.  Little  iron  concretions  are  not  uncommon  in  the  upper 
portion  of  the  bed,  and  these  in  burning  produce  fused  spots. 

The  red  clay  (No.  4)  is  the  more  sandy  of  the  two.  It  is  a 
gritty  clay,  porous  and  slakes  very  quickly.  The  addition  of  32$  of 
water  gave  a  lean  mass,  which  shrunk  10 fo  in  drying  and  5$  in  burning, 
giving  a  total  shrinkage  of  15$.  The  average  tensile  strength  of  air- 
dried  briquettes  made  from  this  paste  was  SI  lbs.  per  square  inch  and 
the  maximum  98  lbs.  Incipient  fusion  occurred  at  1800°  F.,  vitrifica- 
tion at  1950°  F.,  and  viscosity  at  2100°  F.  The  clay  burns  to  a  red 
but  not  very  dense  body.  With  hard  firing  it  becomes  converted  into  a 
black,  impervious  body  in  which  the  individual  quartz  grains  stand 
out  with  great  distinctness. 

The  composition  of  the  clay  is  as  follows: 

Analysis  of  red  Brick-clay  (No.  4),  Lucas'   Yard,  N~.  E.  of  Wilson. 

Moisture 2.31 

Silica  (total)    62.99 

Alumina    13.56 

Ferric   oxide    11.52 

Ferrous   oxide    0.33 

Lime    10 

Magnesia    29 

Alkalies    2.07 

Water  (loss  on  ignition)  6.03 

Total    99.20 


BRICK-CLAY    DEPOSITS    IN    NORTH    CAROLINA.  13T 

Clay    substance    55.95 

Total  fluxes   14.31 

Free  sand  43.25 

Specific  gravity    2.62 

The  insoluble  residue  is  probably  mostly  quartz,  and  the  high  per- 
centage of  ferric  iron  gives  the  clay  its  red  color. 

The  blue  clay  is  also  gritty  to  the  feel,  somewhat  finer  grained  than 
the  red,  and  slakes  slowly  to  scaly  grains  in  water.  Like  the  red,  it 
shows  no  mica  scales.  It  required  30$  of  water  to  produce  a  workable 
paste.  This  was  quite  plastic  and  shrunk  8$  in  drying  and  5.5$  in 
burning,  giving  a  total  shrinkage  of  13.5$.  Briquettes  of  this  air-dried 
paste  had  an  average  tensile  strength  per  square  inch  of  107  lbs.  and. 
a  maximum  of  129  lbs.,  much  stronger,  it  will  be  seen,  than  the  red. 
Incipient  fusion  occurs  at  1900°  F.,  vitrification  at  2050°  F.,  and  vis- 
cosity  at  2200°  F.     The  clay  burns  to  a  red. 

Its  composition  is  as  follows: 

Analysis  of  Lucas'  blue  Brick-clay  {No.  5),  N.  E.  of  Wilson. 

Moisture    1.70 

Silica  (total)   68.90 

Alumina    14.36 

Ferric   oxide    6.04 

Lime    03 

Magnesia    31 

Alkalies    2.30 

Water  (loss  on  ignition)  5.83 

Total    99.47 

Clay  substance  48.72 

Total  fluxes   8.68 

Free  sand 51.75 

Specific  gravity    2.45 

Mr.  Lucas  has  a  second  clay  bank  east  of  the  town,  from  which  he  also 
uses  the  clay  for  making  common  brick.  The  clay  in  appearance  and 
feel,  chemical  composition  and  physical  properties,  is  closely  like  that 
described  above  as  used  at  the  other  yard,  but  the  claim  is  made  that  it 
not  only  shrinks  less  in  burning  but  even  swells  sometimes.  For  this- 
reason  the  clay  was  examined.  The  only  apparent  difference  from  that 
at  the  other  yard,  northeast  of  the  town,  lies  in  its  slightly  higher  fusi- 
bility, and,  consequently,  with  only  the  same  amount  of  firing  as  that 
given  to  the  other  clay,  this  one  would  shrink  less.  It  is  a  gritty  clay 
which  slakes  slowly  and  requires  the  addition  of  33$  of  water  to  give  a 
workable  paste  that  to  the  feel  was  very  plastic.  This  paste  shrunk 
11$  in  drying  and  4$  in  burning,  giving  a  total  shrinkage  of  15$. 


138  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

The  air-dried  briquettes  made  from  this  paste  had  an  average  tensile 
strength  of  138  lbs.  per  square  inch  and  a  maximum  of  155  lbs.  per 
square  inch. 

Incipient  fusion  occurred  at  1950°  F.,  vitrification  at  2100°  F.,  and 
viscosity  at  2250°  F.  The  color  of  the  burned  clay  was  red.  Its  com- 
position, as  shown  by  the  following  analysis,  corresponds  closely  with 
that  of  the  preceding  sample. 

Analysis  of  Lucas'  Brick  clay  (No.  6),  E    of  Wilson. 

Moisture    1.68 

Silica  (total)  68.28 

Alumina    13.59 

Ferric  oxide 5.66 

Lime    15 

Magnesia    47 

Alkalies    2.82 

Water  (loss  on  ignition)    6.00 

Total    98.65 

Clay  substance  43.69 

Total  fluxes   . 7.69 

Free  sand    53.55 

Specific   gravity    2.52 

Other  clays  of  the  same  nature  are  exposed  for  some  distance  along 
the  railroad  track  north  and  south  of  Wilson.  A  number  of  buff  brick 
have  been  made  from  a  deposit  lying  south  of  the  town. 

COMPARISON    OF   CLAYS  FROM  WILSON  AND   WAYNE   COUNTIES. 

The  clays  at  Wilson  and  Goldsboro  are,  as  has  been  previously  stated, 
of  sedimentary  nature  and  somewhat  similar  in  character. 

Experiments  and  actual  practice  point  to  the  fact  that  very  different 
results  can  be  obtained  from  these  clays  by  the  use  of  different  methods. 
Hand-molding,  improper  tempering  and  hurried  burning  give  a  poor, 
porous,  badly-colored  brick.  Steam  power  machines  give  a  much 
smoother  brick.  Auger  machines  were  tried  by  some  and  given  up  in 
disgust,  but  the  machines  used  had  the  shortest  possible  pugmill  and 
the  clay  received  no  other  tempering.  When  rolls  are  used  they  seldom 
do  more  than  flatten  out  the  tough  lumps  of  clay.  In  a  cheap  auger 
machine  the  die  is  often  improperly  constructed,  and  laminations  of  the 
worst  kind  may  be  produced  in  the  brick.  If  the  brick  is  not  thor- 
oughly burned,  these  laminations  will  result  in  the  shelling  off  of  frag- 
ments from  the  brick. 


CHAPTER  X. 
MANUFACTURE  OF  PAVING  BRICK. 

Few  paving  brick  are  manufactured  in  North  Carolina,  but  as  some 
of  the  clays  give  indications  of  applicability  for  this  purpose,  it  may 
be  well  to  say  a  few  words  regarding  the  manufacture  of  brick  for  pav- 
ing purposes.  General  practice  has  shown  that  shales  are  par  excel- 
lence the  material  for  making  paving  brick,  for  on  account  of  their 
fusible  impurities  they  burn  to  such  a  dense  body.  Shales,  however, 
are  not  always  obtainable,  and  then  other  clays  have  to  be  used.  It 
is  highly  probable  that  mixtures  of  clays  can  be  used  in  North  Carolina 
for  this  purpose.  '  A  mixture  of  the  top  and  bottom  clay  from  Emma, 
in  Buncombe  County,  was  tried  and  burned  to  a  dense,  hard  body.  The 
clays  at  Elkin  and  Wilkesboro  also  burn  to  a  dense,  impervious  mass, 
but  they  lack  somewhat  in  plasticity  and  would  have  to  be  mixed  with 
a  more  plastic  clay. 

REQUISITE    CHARACTER   OF    CLAY. 

Clays  used  for  making  paving  brick  should  have  sufficient  fluxing 
impurities  to  enable  them  to  burn  to  a  dense,  impervious  body  at  a 
moderate  temperature. 

Wheeler1  gives  the  following  average  composition  of  a  paving  brick 
clay  deduced  from  fifty  reliable  sources. 

Average  composition  of  paving-brick  clay. 

Minimum    Maximum 
percent.      percent.    Average. 

Moisture     0.5  3.0  1.5 

Silica     49.0  75.0  56.0 

Alumina    11.0  25.0  22.5 

Ferric   oxide    2.0  9.0  0.7 

Lime    0.2  3.5  1.2 

Magnesia    0.1  3.0  1.4 

Alkalies    1.0  5.5  3.7 

Water  (loss  on  ignition) 3.0  13.0  7.0 

Total  mixes   13.0 

Chemical  composition  alone  does  not  determine  the  use  of  a  clay  for 
paving  brick.     It  should  be  quite  plastic  to   permit   molding  without 

1  Vitrified  Paving  Brick. 


140  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

tearing  in  a  stiff-mud  auger  machine,  but  not  excessively  plastic,  other- 
wise laminations  result. 

From  a  commercial  standpoint,  it  is  of  course  desirable  that  the 
shrinkage  in  drying  and  burning  should  be  moderate,  and  that  the  clay 
will  permit  drying  in  24  to  36  hours.  In  fact,  the  lengthening  of  any 
of  the  stages  of  the  process  of  manufacture  increases  the  cost. 

An  important  point  is  that  the  greater  the  difference  in  temperature 
between  incipient  fusion  and  viscosity  the  safer  it  is  to  thoroughly 
vitrify  the  brick.  The  difference  in  temperature  between  incipient 
fusion  and  viscosity  should  not  be  less  than  250°  F.  and  preferably 
400°  F.1 

The  color  of  a  paving  brick  is  no  indication  of  its  quality. 

MANUFACTURE    OF    PAVING   BRICK. 

If  shale  is  used  it  is  first  crushed  in  a  dry  pan  and  then  screened. 

The  screened  clay  is  mixed  with  water  in  a  pugmill  of  the  type  de- 
scribed under  building  brick. 

From  the  pugmill  the  clay  passes  into  the  stiff -mud  machine,  which 
has  been  already  mentioned  (p.  97).  Few  paving  brick  manufacturers 
now  use  anything  except  the  auger  machine.  The  brick  may  be  either 
end-cut  or  side-cut  according  to  the  clay.  Re-pressing  the  green  brick 
is  also  commonly  done,  but  the  manner  of  re-pressing  may  have  a 
marked  effect  on  the  wearing  power  of  the  brick. 

Experiments  by  Prof.  E.  Orton,  Jr.,2  have  shown  that  end-cut 
re-pressed  paving  brick  are  the  toughest. 

The  brick  are  generally  piled  on  cars  and  run  into  tunnels  to  dry. 
These  tunnels  are  heated  by  steam-pipes,  or  coal  or  oil  fires. 

The  cars  are  run  in  at  one  end  and  always  discharged  from  the 
other. 

Paving  brick  should  be  burned  in  down-draft  kilns,  as  they  give  far 
better  results  than  the  up-draft  ones.  The  kiln  may  be  either  circular 
or  rectangular.  Circular  kilns  have  small  capacity  and  are  cheap  to 
erect,  but  little  used  outside  of  Ohio.  Their  capacity  is  about  25,000 
brick. 

Rectangular  kilns  of  150,000  to  200,000  capacity  are  the  most  used. 
There  are  several  types,  but  their  principle  is  the  same.  The  flames 
and  heat  enter  the  kiln  at  the  bottom  and  pass  upwards  in  jDOckets  set 
against  the  wall  of  the  kiln  and  running  half-way  or  three-quarters  to 
the  roof.  The  heat  escapes  from  the  top  of  the  pockets  or  bags  into 
the  kiln,  passes  downward  through  the  brick  and  out  through  the  open- 
ings in  the  floor  to  the  flues  leading  to  the  chimney. 

1  Olchewsky.  in  Post.  Chem.  Tech.  Analyse,  1890,  and  Wheeler,  Vitrified  Paving  Brick,  1895. 

2  Clay  Worker,  Feb.  and  March,  1897. 


MANUFACTURE    OF    PAVING    BRICK.  141 

The  difference  between  the  various  makes  of  kiln  consists  in  the  size 
and  shape  of  the  fireplaces,  arrangement  of  flues,  slight  differences  in 
bag  walls,  number  of  stacks,  etc.  Among  the  various  types  may  be 
mentioned  those  of  Eudaly,  Graves,  etc.  Figure  2  of  Plate  X  (p.  101) 
shows  a  Eudaly  down-draft  kiln. 

As  paving  brick  soften  somewhat  in  burning  to  vitrification,  it  is  nec- 
essary not  to  make  too  many  courses,  otherwise  the  lower  ones  are  liable 
to  be  crushed  out  of  shape.  The  water-smoking  period  varies  accord- 
ing to  the  clay,  but  3-4  days  is  the  average,  and  the  burning  takes  from 
4  to  7  days  longer.  The  kiln  should  be  cooled  very  slowly  in  order  to 
anneal  the  brick  and  give  it  that  great  degree  of  toughness  character- 
istic of  all  good  pavers. 

Great  care  should  be  taken  to  avoid  any  cold  air  entering  the  kiln 
and  checking  the  pavers. 

At  several  localities  continuous  kilns  are  used  in  the  burning  of  pav- 
ing brick,  but  while  they  work  fairly  well,  they  are  not  yet  a  thoroughly 
established  success. 


142 


CLAY    DEPOSITS    IN    NORTH    CAROLINA. 


m 

< 
o 

I— I 

o 
o 

w 

o 

o 

m 
m 

<! 
O 


Q 


•sj^jBrnaH 


snoau^n^osiH 


O^ 

3^  2  j, 

3    • 
O 

a     z. 

u 

3       3 

© 

02      02 

pE| 

*        # 

CM         OJ 

nOffl 

s   & 


1.      o 


•pUBg  Q9J& 

CO 

d 

00 
CM 

o 

o 

k6 

Q 

o 

co>a 
•Wio 

kO  CO 

8 

CO 

s 

CO 

eo" 

8 

OB 

i-0 

g 

is 

•saxnu  is^ojj 

CM 

6 

OS 

o 

OS 

oon 

Oll-I^H 

£5g 

od  oj 

C5 

CM 

I— 

£; 

03 

1 

o 

•aou^sqns  ^bjo 

6 

8 

M 

o 

oi-^io 

-"#  OS 

IOCS 

^#co 

OS 
CO 

OS 

os 

CO 

8 

CM 

O 

CO 

~ 

X 

•pnoj, 

o 

6 

OS 

eo 

CO 

o 

o 

o 

o 
o 

^COCO 
t-  fc-Ci 

oleics 

OiOICi 

lOiO 

cio 
©o 

cm 

s 

CO 
CO 

o 
o 

CC 

X 

X 

| 

X 

1 

s 

•UOIIIU.^1 


•saij^lV 


O 

X 
CM 

X 

OS 

o 

«-" 

^ 

?1 

•Bisaa.S'Bpi 


JS        *H 
-       CM 

CO 

Mt-t- 

COO-H 

J- CO 

§3 

CO 

s 

CM 

CM 

CM 

1       CM 

O 

CO 

ooo 

CM  i-l  CO 

S3 

s 

o 

J3 

cr 

£ 

£ 

•8  rail 


«     § 


'apiXQ  0UJ8.J 


•^airaniv 


Ci  MM. 


io-hco  eo 

cscm  t-  o 

oi  i- co 


x  t- 


-i  — I  CM  r^ 


•(TB^ox)  ^e>n!S 


•aan^sioj^ 


SS2        §S 


3 

.  3 

H    0 

gj    © 

Si 
to  B, 

9  >» 

R    as 

a?  ^ 

cq  *i  =  .2 


:W-° 


O  08 


u  s 


OS  cS 

g  sa 

cS  cS 
P=  .3.3 
§    g§ 

5     ®   ®   Ld 

to  P^Ph  © 

««  - 


c  o 

fc,  3S 
O  0JD 

as 


H 

to 
& 
o 
o 

S  «  o 

b? 

o"2 

Puca 


?  o 

-«j    3 

o 

0 


•  o  ;  o 

;0Q    'qo 


3  ;  3  :  £  I  "8 

8  :  2  •      • 

g     •  ™  CD  D     -3 

=2  :  cs2^  :  © 
Q  :DHb  :  ^ 

0  Si  3  M,2  h  *  ti 

cS  CO  03-3  o  ©a  a 

i  p  s  a  «  o  j-  ? 


3  >-.  S  ci' 
©  cs  is  ^ 


^3  S^a  c  ©  S  ©  &- 
Dh     cu     b    U 


o  P-  « 


paqiaosacE 

aa'aqAv 

^aodan  ui  aS^ 


on  ^aoiBaoq^'i 

1B0ITX191[3 


ir>  x  ?> 
ot-t- 

lO  iC  UO 


— I— H  »0  1— I 


IJiodzyi  srq^  ui 
pasn-o^  Piaii 


•«*<      ic      co      r- 


ANALYSES    OF    NORTH    CAROLINA    CLAYS. 


143 


-•     "8    "2 

1-H  0  0 

O         ^0^  © 

<»       ej  — I  o~ 

03    co 


'V 

-co 

V 

a;  cv 

M 

id  id 

t- 

o 

o  o 

o 

o  o 

^ 

55  55 

co  co 
3  • 
O 


»o     ion 


i-l       COOl 


mo-f 
CO  cc  oi 

oioieo 


°co 

WO 


££ 


2 

oco 

cot- 

lO 

o 

lO 

OS 

CD  © 

o 

o 

»o 

© 

©o 
uo  t- 

coooi 

©  lO  CO 

© 
3s 

J28 

© 

Ojl 

© 

CO 

kOlO 

o 

-*eo 

OJ 

CO 

co 

o-* 

-*CO 

»n 

CO 

CO 

04 

CO 

OS 

oco 

CO  lO 

t»H9 

lococo 

o 

CO  CO 
—  01 

kQ 

01 

CO 

CO 

1C  01 
kO 

CS 

coo 

CO 
OS 

CO-* 
CO  O 

to 

2 

© 

© 

I— 

0! 

OS  CO 

©CO 

-*CO~* 

CO  ON 

CO 

CO'* 

OSOl 

•o 

© 

k0 

©CO 
OJO 

O 

coco 

© 

fc- 

—  Ol 

-# 

»© 

s 

fc- 

t-m 

—  ©CO 

co 

COCO 

"* 

*-' 

01 

oico 

£ 

CO'* 

OS 
OS 

o 

CI 

£5 

CO 

0! 

o 
1- 

WO 

© 

coco 
-*co 

COO  CO 

©t-©l 

lO 

no 

COL- 

CO 

s 

-* 

—  CO 
01  01 

o 
(5 

cot- 

lOCO 

§ 

so 

£8 

CO 

»o 

CO 

CO 

OS 

CO 

ffijt 

—  CO  01 

CO 

»o 

COCO 

cot- 

CO 

OS 

© 
eo 

© 

"f  fc- 
os># 

o 

COOl 
0d« 

01 

lO 

OS 

lO  — 

CO 

o 

© 

^ 

OS 

© 

coco 
©io 

CO  — OS 
©L-fc- 

© 

coos 
mco 

© 

8 

00 

COCO 
OS  kO 

o 

ft 

oo 
oo 

OS 
OS 

8 

030 
OTO 

© 

© 

as 

OS 

8 

OS 

© 

O  © 

as  os 

OSOSt- 

OS 

as 

BS 

o 
© 

8 

rs 
© 

OS  OS 
OS  OS 

00 

kO© 

C-00 

JO 

8 

©CO 

coo 

eo 

CO 

o 

00 

* 

8 

^H© 

CO  CO  CO 

o»oco 

o 

CO 

coos 
©t- 

s 

o 

CO 

© 

CO>(0 

mco 

ft 

I— CO 

CO 

OS 

00  ^H 

© 

© 

© 

m 

>OiO 

lO'OCO 

CO 

—  o 

CC 

CC 

CO 

CO© 

co     oo 

01        CO  — 


■■#      lO      lO 


o     com 


CO  — — 

CO        CO  CO 


1— I      t-      -* 

co      co      co 


coco 
coco 


Ot— OS 
CO  lOCO 


Ol        Ol  —        — 


CO         Ol         CO 


Ol        COOl 


—        —        CO 


■eH       O       O  — 

in     i—     t-t— 


H 

85 

& 

o    . 
H  1 

K  CO 
O     ,   , 
PR    t>>>> 

oo 

OP 


P    S 

O    ° 

o  M 

w  © 

o  £ 

o 

a 


s^ 


|J  tSCQ  O 

5  til 

d  a  _ 

a;  ^ 


o   . 

u     • 
O  cS    • 


:  oj  g 

■    U   O 

:Og 

:  a 

m  t» 


-   .  -.S-o.-o 

1 1  i  S3  £  S  i 


o^  :  v 


P  PH 


5  aS'-C  2  O 

b  ^ 


2 


PSP 


:S  -0 


a 

Z    a     .     -   .  09 

fci      ,  co  ^j  go  bo 

u  —  a  .  aa2 

«    >H   o         Oft 


DQ 


"  o    _  c    . 


5    o    o 


£  ;# 


^     •  0 

o  :s  s? 

OS  .  •  Q  > 


Ol  N 

CO 

lO  ■>* 

i—  CO 

© 

00 

© 

CO 

§ 

00 

s 

l~lz2 

OS 

© 

?! 

€•» 

CO 

eo 

© 

OS 
lO 

0» 

NO 
lOO 

ta 

eo 

lOiO 

oio 

«*  lO 

lOlO 

CO 

U5 

»o 
»o 

cS 
lO 

CO—  ■* 
<*  CO  KO 
i.O  i.O  i.O 

CO 

CO 

01 

Ol 

f» 

5 

X 

§ 

io      ko     o     us 


144 


CLAY    DEPOSITS    IN    NORTH    CAROLINA. 


■* 

© 

S3 

© 

©  So 

ill 

M 

•ss[j^caa}i 

► 

£ 

a 

fe 

© 

© 

^A,*,* 

£4 

M 

M 

f. 

o 

O 

_o  _CJ  o  © 

© 

o  o  o 

o 

~ 

QQ 

02 

caasa 

a 

1ZZZ 

DQ 

- 

z 

CO 

t- 

§ 

CO 

icomo 

^■00 

o 

50^'- 

i^ 

o 

^ 

•pires  QdJjti 

cc  t-eo 

o 

5S 

in 

CO 

—  CScOOl 

00  — 

to 

r"1 

t-^ 

m 

m  m  co 

L- 

m 

IN 

I-H 

so 

CM 

fc- 

loom:! 

i— CO  OS  OS 

lOrt 

o 

_. 

M 

•saxni^  ib;oi, 

""? 

"t 

"^ 

eo—* 

00 

~*oco 

•"< 

m 

£ 

co 

«o 

CM 

OlXOfO 

com 

m 

eom-* 

X 

t- 

eo 

£ 

t. 

so 

OS 

CO        •"#« 

COOl 

coos 

O  CO 

ojm 

CO 

tHOiO 

CO 

•aoireqsqns  Atb\q 

d 

oi 

CO 

ot 

CO 

s 

oo     eo  co' 

CO        TttlO 

L~ 

L~  O:  CC 

s 

■-0 

?i 

o 

CO 

est 

COOOCS  00 
r-COCON 

§o§§ 

CMOS 

Ol 

01 

'I^o^ 

o 

to 

CO 

as 

GO 
OS 

OS 
OS 

o  oox 
oooa 

cscs 

OS  OS 

OS 

as 

as  x  cc 

» 

s 

X 

O 

°^ 

•sno8UBnaosii\[ 

d 

00^5 

8 

CD 

f^ 

•UO[lTU.8f 

00 

gs 

CM 

CM 

CO 

ot-oieo 

01-*m  CO 

OiO 

cs  ea 

eo 

-oco 

m 

- 

•^ 

no  ssot  J.B%TSji\ 

to 

CO 

CO 

S 

lOi-mb- 

CMt- 

CO 

*-*'* 

t- 

•* 

t- 

to 

01 

CO 

cm  cm  m  w 

o  -=> 

0 

•SBii^mY 

c 

COi-ifllO 

L- 

^xe: 

t- 

°J 

t« 

ki 

rt 

CM— (CM 

rl  — t 

—  01 -^ 

CM 

Ol 

* 

) 

o 

CO 

co 

00 

im-^ho-* 

Ss 

ta 

?!2^ 

- 

•BisauSepi 

o 

*~J 

t 

o 

" 

"^ 

o 

to  . 

"" 

m 

CO 

CO 

nMiOH 

i— in 

m 

ia 

•araii 

o 

CM 

TT 

m 

«— ieo 

CO 

to 

CM        Ol 

■* 

lO 

^ 

J^ 

_ 

a 

•apixo  ouaaj 

c 

CM 

CO 

COOCOO 

^OS 

eo 

-*xm 

CM 

o: 

CM 

ki 

co 

■* 

r"1 

tOSffJt-O 

CM  CM 

■** 

— i  —  i-i 

■"* 

-* 

X 

CO 

,_, 

SS 

_ 

-* 

•■Baiairi[Y 

CO 

C3 

T-ieoccm 

eo 

xoso 

o 

Ol 

CM 

to 

■* 

CO  CO  >*  CO 

iO 

•"5  OS  CO 

OS 

CM 

CO 

r,KH'H 

rt 

CN 

o 

00 

o 

iQOian 

coo 

OS 

com  co 

— 

s: 

X 

•(i^nox)  ^onis 

o 

t-^ 

o 

odosino 
co  m  co  co 

CO  CO 

OS* 

occco 

1^- 

X 

2 

in 

iC 

m 

t- 

LT 

*■* 

o 

com 

^ 

xt- 

X 

- 

•aanqsiopi 

o 

ft 

ea 

CO  i--  CM  CO 

rH 

go    • 

3  '• 

CO 

© 

a  i 

6 

>5 

o 

eg  ; 

a  . 

^ 

a  : 

s 

ffl  : 

o 

p 

^j  • 

_c 

CQ     . 

* 

...  : 

a 

o- 

It 

CO 

© 

© 

► 

c 

93 

>&£ 

0^ 

©  : 

o  . 

F 

LOCALITY. 

B 

Z 
19 

C 
Q 

& 

C 

o 

z 

(3 

«    .CM 

<u   .    - 

o    •  © 

os  :  a 

gB|3 

d  ©    .  C 

©  O  o  c 

©  .  © 

a     o 

> 

B 
t3 

c 
o 
z 
c 
o 
< 
3 

s ; 

CO      • 

+2    '. 
w     • 

©   • 

*  : 

^  : 
es   . 

fl   . 

a  : 

3T3 

o  a 

es  cS 
^-, 

CO 

©^ 

5 

B 

U 

c 
a 

a 
as 
p 

z 
ts 

o 
pa 

a 

4- 

c 

!- 
0 

_: 

'C 

f. 
c 
> 
a 

C 
a 
C 

F.  W.  Shuman's  yard,  Charlotte 
P.  M.  Sassamon's  yard,  Charlotte 
Upper  clay,  J.  Asbury's  yard,  Ch 

> 

H 
Z 
& 

c 
o 

S 

o 
0 

H 
Z 

o 

Z 

ta 
c 
O 
z 

c 

m 

3 
fit 

.2 
"S 

B 

m 

a 
© 
a 

W 

P 

>■ 
B 
Z 
& 

G 
Q 

Q 

Z 

s 
= 
a 

5 

-J 

I 

a 
M 
c 

"5 
c 

s. 
c 
c 
c 

: 

B 

f 

! 
1 

>-«  - 

j 

3*  : 

o  ! 

fe  : 

©  : 
S  : 

S.  : 

©  . 

©  : 
©  : 

■w  _ 

cc  g 

-;  cs 

m 

E- 
Z 
t= 

C 

o 

z 

c 

X 
po 

C 

& 

c 
a 

- 

! 

c 

) 

l 
s 

1 

s 

> 

B 

z 
!= 

C 

© 

- 

i 

© 

«  r 

x- 
c. 

f 

1 

•paqxaosad 

cm  n  oi  oi 

CO 

cr 

X 

aaaqAv 

fc- 

CO 

coco 

CM 

•o>i  ^JOi'eaoqBT; 

CO 

£ 

CO-H  —  00 

OS  CO 

t- 

co  t-ao 
coco  CO 

s 

m 

reoituaqo 

in 

«o 

JO 

m  m  m  m 

mm 

m 

l^i  XO^^i 

•qaoday;  stqq.ni 

^ 

68 

O  — Ol 

as 

(  pasn  -om  piai.j 

CO 

0 

o  **>■» 

HCO 

cog 

^ 

* 

ANALYSES    OF    NORTH    CAROLINA    CLAYS. 


145 


T3 

.-a 

0) 

<u  a> 

s* 

o 

£  o 

y$ 

MX* 

£&MM 

O 

O  O+j 

OpOO 

u 

'u'u  O 

oo-St 

ca 

ecasz; 

cc^cacq 

6  2 

O  -J 


£  ,<* 


I  b 
g* 


s  :  ° 
■  oj 


So 

O^5 


h5S 


£5£ 


g  O  a>  «Q 

gl6l: 


b*     °  S 
0)     ji  o 


.2.2 

(2£ 


CO 

m> 

m 

ire  ire  o 

©rlfc- 

oireoire 
ocoo^ 

ire  ire  ire 

o 

m> 

ire 

00 -*o 

^ireire 

^NCDO! 
CMCO"*'* 

cohere 
-*mire 

d 

CO 
CM 

fc-CO  -H 

05  CM  ire  tH 

—  COOS 

*" 

m 

t- ire  oo 

£-  CO  N  L- 

-*oot- 

S 

o 
ot 

GO 

l-coco 

'cHOICO 

coco  -*  ire 

OIL- CO 

o 

is 

CO 

^ 

r-COOS 

m  ->#  -# 

ireL-^r- 

l-  co  co  ire 

ire  co  co 

o 

00 

CO 

-•"COCO 

ococo 

coco-#o 

CM  "■#  N 

O 

£ 

OS 

OS 

§22 

oiao© 
cso.  oos 

OS  OS  J— 

OS  OS  OS 

CO 

6 

o 

CO 

t- 

co 

CO 

IM  COCO 

coo  ire 

cooom 

L-^*  CO  ■* 

Cscst-L-^ 

co  coo 
ocoo 

comco 

c- 

6 
ft 

ire 

CM 

oi 

Ir- 

O  CO  CO 

tCWrXM 

co  ire  os  cd 

'  CMO}-* 

t-OfH 

oco-* 

CMNrH 

CD 

6 

ft 

5-1 

IO 

ire  ire  co 

CM^HCO 

—  OOJ  GO 
-*t-i— lO 

CS-^t~ 
OICO'* 

to 
6 
ft 

s 

S 

ooire 

CO-*f  CO 

mt-oo 
^*iret-o 

©corns 

6 
ft 

r» 

CO 
CO 

si 

OS  CD  ■* 
CD  — O 

CD  CO  •"# 

CO  CO  OS-* 

-*  COCS-h 

ire^i~-H 

01-*  CD 

m  o  co 
r-ieoia 

CO 

6 
ft 

CO 

cs 

CS 

to 

ire 

—  ~#  — " 
cot- in 

L^COCO 

t-  L-  —  CO 

ff  >  OS  OS  CO 

l-^-#  -#o 

CM  CM  OJ  CM 

COtC  OS 

mcom 

CO-*r'cO 

CN 

6 

o 

CD 

so 

co 
o 
o 

mom 

OOSCS 
CO  CO  CO 

go  -*  mure 

COOlt-n 
-#  ■*  CO  CM 

t^>  l^  iO  lO 

OS  ©CO 

OS_  OS  01 
oicc  CO* 

CO  CO  CO 

P 

>re 

CO 

o 

CO 

com  cm 
m  co  — 

coocoo 

NNOh 

*h  oi  —  oi 

--©CO 
COL- CO 

NrHrH 

o 

pa 

&      . 

c  m 
5  2 


uJ  en 


(J,  ^  ^J, 

-* 

t-co 

Ol 

CO 

CO 

1—1 

1—11—11—1 

~ 

^^ 

OS 

nn 

— 

cs 

mos 

m  m  m 

m 

m 

ire 

m 

i..  l.. 

\ 


10 


146 


CLAY    DEPOSITS    IN    NORTH    CAROLINA. 


'A^IA'B.lf) 

og'ioads 


OOOH 

in  -#  -* 
oi  01  oi 


01        m        CO 

oi      oi      oi 


•pouanq 
u9qAY  ao[OQ 


©  ©  CD 
■^   ■-   ■- 


COO 


m 

-op 
©  i 


-CO 
©  © 


■      DQ         SQ         V 


•saxni^  ib^ox 


—  t-     t-     o      eo      n 


< 

•A^isoasjA. 

ooo 

O  OO 

cococo 
oi  n  cm 

OOO 
OiOO 

SI  SSI 

oo 

OI  OI 
OlOl 

o 
1ft 

o 
o 

OI 

o 
o 

CM 

o 

M 

o 
oS 

oi 

5 

52 

0101 

be* 

K 

0 

H 

Q 

•nor} 
-•bouu^ia 

irtOO 
OI  01  CM 

ooo 

OlC"0 
01  01  N 

oo 

oo 

0101 

o 

o 

01 

o 
o 

CO 
OI 

o 

s 

0! 

CO 

IN 

O 

o 

01 

;2 
oi 

o 

WW 

^naidioui 

OOiffl 
CM— (i-l 

5=2° 

OiOO 

ooo 
oi  oi  oi 

oo 
m  m 

OS  o 

o 

OS 

o 
o 

01 

1 
0! 

| 

s 

2 

0C 

oo 

3  o 

o 
o 

&q 

H 
P3 
W 

Ph 

o 

Ph" 
Ph 

O 

M 
CC 

!>H 

W 

Ph 

o 

.J 

PP 
H 


•^io 

jo  aan^xax 


©jg  a 

OS^1   3 


cl  cJ.rt 


.5 
2   £ 


03      rs 

8  § 


•SuiJi'Bis 


*&H0RSB[<I 


o_o  o 


co  as  <Z 
a  58  © 


OS    GO 

cs  C3 


O       O 
53      55 


> 

^ 

'ui  -bs  aod  "sqi 
•q^Su8.ns 

00  t-o 

ooo 

—  CO 

coco 

1 

CM 

•>* 

U- 

in 

eo 

m 

in 

m 

fi 

2  X 

•ui  -bs  J8d  -sqi 
•q;Saaa^s 

9JISU91  9#FJ9AV 

*0-*OS 

cooot- 
omco 

OO 
COM3 

CO 

00 

co 

M 

CO 

OO 

03 

-*1 

3 

DC 

01  o 

0 

H 

o 

X 

y 

Ph 

•gSB^uiaqg 

CO"*t- 

CO  — -H 

is 

o 
os 

o 
6 

ro 

CO 

m 

"? 

co 

00 

i£=5 

•gSB^uiaqg 
9aii; 

oo  com 

■**-*t- 

-*m 

t- 

eo 

lO 

m 

eo 

m 

m 

- 

mo 

•e.SBJiuiaqg 

lOeDM 

ost— * 

eo 

as  o 

Ol 

eo 
o 

CO 

^ 

OS 

t-^ 

00 

X 

O  30 

ci  c  a 

C3  CS  C3 
Cu  Z)  05 


O  C       T3 

bo  co      o 

t         ^     O 


•a^sBd  8[qB>iJOA\ 

9A0  0^  p9ppB 


o  <g 
W  3: 


.   CB- 

:  3* 
:3 


S    PS 


o  fl 

O    cs 


O    d> 


a 

ee* 

bD 

O 


a  ™ 


CD  03     ► 

P-O 


-   i 

o  - 
P-C3 


ci 

To 
8t 


6  » *» 


:  o 

o  : 

DQ 

;C»    ; 

•     ^ 

.     ^   • 

•  O 

•  o   • 

:o 

•o  . 

•  o 

:  ©  : 

•  u 

•  i-  • 

■  X 

:cq  : 

■  "0 

:*  : 

.  c  • 

■  cS 

•  a   ■ 

•  cp 

•    Qj       • 

> 

'.    >       '. 

•  © 

©       - 

O 

:<->  : 

a>  tj 

•  >>  : 

©  C3  ©  C3  P  O  ©"o  © 


C3   O 


_    tO  fci  b  **  o 

c xi _.  « 2 © S 

5&0&c^O=-0 

W0,      0-       b      O 


©  © 
&   - 


•paquosap 

oaaqAv 

^.iod9H  in  9^^^ 

CO 

o 

oi  co 

oo 

-Hint- 

ooo 

mt- 

eo 

—  Ol 

00  00 

co 

X 

X 

o 

1 

o 

3 

—  23 

•jgqrariK  PI9Id 

o 

—  Ol 

cjcom 
in  m  o 

in  in 

s 

CO-* 

in 

eo 

5 

3 

s 

coco 

PHYSICAL    PROPERTIES    OF    NORTH    CAROLINA    CLAYS. 


147 


to-*      toco     m     ci     -*o^h 
-* -*      ->*i  -*i      10      m      -*io»o 

©Jci     ©ici     oi     C4     ©icici 


cououo 
©i  ©i  ©i 


©ici 


<-h  CO 

no      if: 
©i     ©i 


01  © 

PhPh 


d  tL® 

o 


.  PS 

0,0 


rOrOrO 
0  ©  OJ 


0 


c;  o 
cico 


oo  oo  ooo  ooo 

o  no  oo  ifloio  moo 

IB  -*>  -*CQ  nO  CD 'ti  -*  CO  ■<* 

©1©1  ©}©i  (MMJ1  ©I  ©I  ©J 


>o  >o  > O 
fdg,C  2  —  s 

<J  ©J  <  11  <j  ©i 


oo 

L-  uO 
CI  01 


oo  ooo  ooo  o 

o  o  iooio  icieo  o 

co  — i  eo->*"M  cm  i— i  -  •  co 

©I  ©1  ©}©*©!  CI  01  ©1  CM 


oo  ooo 

o  o  ia  o  ia 

^- OV>  i-h  ©I  o 

©1—1  ©i©l©! 


38; 


CO        CO        CI— i 
CI        ©}        CI  ©i 


a  a 
o  o 

OO 


&  0  0  0  0  0 

pj  co  co  co  co  co 

— |  ci  c3  C3  cS  cS 

§  OOO  o  o 

£  ooo  oo 


CD'S 

£3 


0 

o 

0 

a 

*j 

a 

c 

© 

-•- 

>> 

a  >. 

d-Z  ht 

0 

0 

> 

O 

> 

0  o 

ft  ^^ 
>o 


0      0 
a     d 


coco      coC,      '1:       <»  <*  £       £ 


•fePq 


£  *»  P  P  P 
O  §  O  OO 
CQ       Ph      GO      GGOQ 


d'S  c'jd  d     'd  'Sd'S  a 

cS  du  o3  be  cs^o  o-o  eg 

CP--H  cu-rt  0  •     O  O  O  O  0 

^5o  h133  hi     o  O^O  ^ 


■a 

.  •  o 

fl-Og, 

0  o  >, 

►JO  *■< 


►J> 


P      P 

o     o 
55    c/3 


I 

t^co 
c> 

C5COCO 
^-HO 

CO  »-  o 
as  co  2 

CO 

O  CO  CO 

lO  CO  — i 
nN 

CO 

OJiO 
CI  CI 

CI 
CI 

t- 

CJ 

fr- 
ee 

CD 
CO 

CO 
iO 

1—1 
co 

CO  1(0 

co  co 

coo 
©* 

t--#CO 
^#  —  CO 

uO  C35  m 

m 

CO— '  CO 

Tt<lOO 

r-ICl 

Ci 

-*t<05 

Cl—I 

o 

CM 

<o 

eo 

C! 

lOOO 

lO 

CO 

IB 

©i 

co  no 

coco 

ci  co  co 

>ra  co  ph 

co 

CO 

CO 

comic 

-¥ 

-*  t^ 

o 

CO 

C! 

I— 1  —1 

^; 

ift 

lO 

coco 

COlO 

CI  CO  CO 

CO  CO  CO 

>c* 

lO  nOiO 

« 

coco 

* 

- 

5 

-*ua 

t- 

UO 
UO 

CO 

oo; 

O— 1 

ocoo 

CS  O  00 

CO 

•os 

CO 

coob 

o 

COOJ 

CO 

<M 

CO 

COOS 

o 

uO 
OS 

CI       CO       ox 


S? 
S  .s 

CO    ■" 

o 


ft  , 

COrJ3 


g  p'C  0 


►.?/ 


O   csj; 


•       cS    • 

:  :  o  : 

:  PS  : 

!  o  s*  : 

:^S  : 

.  h^  : 

•?§:• 

:*J: 

.  ->-  O    • 

:  e,^  : 

•  >>*5  . 

■  cs-£  . 

:  o 

;_*»■« 

.    »   CO 

•■8*  : 

O    .^3 

°  °  M 


5  "p,  9 

o*j  o 

I*  a 

ft       .QJ-C 


J3  tf^ 

o  d  0 
o  o^ 

ssa 

^  o 

BSS  c3 

1^ 

!  &  -  © 
ojs  c  g 

^  ^^  2 

o  i  "d  o 
a  2  c S 


.  03 

C    sS 


z  as  •  r .  a 

o  5-a-j.s-s 


OaOH^ 


;  0  o 
t£"d 


■  -a  ^  - 

t-  o-r  0 


0  tJ  °,'  2 
o  t^dEnd 

0  o"3  ° 


o    £    £    a 


148 


CLAY    DEPOSITS    IN    NORTH    CAROLINA. 


otjioadg 


n  ©i  01  oa 


©i  ci  ©i 


•potunq 
ueqAi  aoioo 


■CO 


©2  ©  © 

P5 


.  CB  © 

:£2 


©  ©  ©>h.2 


•saxnj^  i^oj, 

t- 

©i 

13.15 

8.30 
13.98 
10.93 

Iff  I— 1 

COr-J 

coin 

COO  CI 

tow 

CO  iff-* 

cc 

Cl 

GO 

o 

CO 

•a 

cc 

Cl 

M 

< 
ft 

CO 

OS 
0 

s 
0 

•i£;isoosiA 

*3©1 

oo 

S3 

©1©1 

oooo 

lOClOO 

©icocico 

<JJ  ©1  CI  5J 

ooo 

ooo 

iff  iff  iff 
Ci  ©I  Cl 

©1CICI  >   > 

o 
o 

Ci 

Ci 

ci 

| 

a* 

•nor; 
-BOUii^A 

CI 

oo 

05  3d 

o  ooo 

LtOOO 

©1  CI  ©1  ©l 

ooo 
ooo 
raeoeo 

OlCMOl 

ooooo 
o  o  iff  iff  ia 

©i  ©1  ci  ci  ©i 

Cl 
Cl 

o 

Cl 

Cl 

© 

Cl 

Cl 

Cl 

•uotsnj 
^uaidioui 

o 
o 

CO 

©1 

OO 

§8 

01  c^* 

oooo 

l-  OiOO 

ooo 

ooo 

C1C1C1 

ooooo 
£Sficlcl 

CI  Cl  ©1  ©1  Cl 

o 
o 
o 

Cl 

g 

00 

£ 

s 

©  CD 

m  w 

u  U 

o  o 


.  ©  9  © 

©  M   5  IB 

.£  03^  ci 

^o|o 


(s^fets 


•ytyioi:jS'eic[ 


jr  ca  as 

O  c3  oS 

03  fef^ 


l^^fa-^ 


4i  +S  -U 

02  02  as 

ci  *  cc 


o  o_c_c  c     c 


§ 

•ui  *bs  jad  -sq^j 
ojisuoq.  'xvjfl 

CO 

coo 

SL-O 

m  ■»  »ff  ci 
cs  ci  ci  t- 

©1©1* 

^f  CO  to  Cl  — 

3 

Iff 

2 

L~ 

X 

•ui  -bs  aed  -sq^ 
•q^aaa^s 

9IlSa8J  0SBJ9AV 

US' 

COt- 

CO  CO  iff  o 
CO  Cl  O  CO 

050^ 

o  co  iff  o  co 

CO 

- 

S3 
Cl 

s 

Cl 

K 
O 

K 

•aSBJfuuqg 
T^oj, 

Cl 

cO©l 

1—1  .— 1 

CO 

HOHN 
r-1        ©J.-I 

COClOi 

Iff 

CO  -h  Cl  Cl  — l 

- 

CO 

ci 

s 

~ 

a. 

•8^HJini.iqg 

CD 

coci 

CO*  CClff 

ooco 

OCCCOOfc- 

CO 

- 

3 

o 

CO 

•a-SB^maqg 
Jiy 

. 

coo 

CO  iff  CO  fc- 

CO  CO  CO 

Iff 

■*  CO'*  co* 

CO 

cc 
cc 

oc 

*- 

• 

S3 

fl  a 

C3 

03  cs 

© 

©  © 

h! 

i^hI 

rci©cc 


a  c  c 

03  C3  03 
©  ©  © 


c  a  c  c  a  ^3 

C3  03  C3  C3  03  O 

©  ©  ©  ©  ©  o 

h!^m^^  o 


o^SBd  aiq-B^aoAv 
GAiS  o%  pappt? 


Cl  iH 


©J3 

^o 

O    - 


D  Is0.' 

(-,  O  h  C3  3 

J   >»  fl  o  ■_• 

W     03 

D  ^ 


„    j-  S  03  >, 

§o^^^ 


«(-!  ^  «tH 

0  o  ° 

g  in 


Po^ 


O   on         K     s 

fe5  "5-   -    ©-    "* 

o  -£J  *   a    -J 

«|S*JS    © 


E- 

z 

p 

C    U) 

O    C 


re  © 
c  « 


&  -'    50 

SI  8  S 


fc  « 


w  ©~ 


c 

04 


II 
s?  S 

p    as 

© 

B 

1-5 


•paqxaosap 

OjaqM 

U0d9^  ui  aStJd 


CO  J—  X  t—  CO 


•aeqmn^  ptsi^ 


Ci  Cl  Ci  Ci  C-i  Ci 


PHYSICAL    PROPERTIES    OF    NORTH    CAROLINA    CLAYS. 


149 


iClfflO 

CO 

tfflTd 

(MIMCQ 

CI 

©a  n  n 

"313 

g''d. 

.  OJ   Ol 

£  <u- 

"D«^ 

T3 

0>  +j  ,_ 

o> 

1* 

Mm 

« 

© 


03 


OJ  0>, 


Em     fafai3 


JQ 

°o 

G3 

co  so  t- 

t-  GO  rH 

L-irico 

o 

COL--TH 

CO 

GO 
CO 
GO 

OS 

o 

g 

co 

ooo 
ooo 

o 
o 

ooo 

ooo 

C-(COCO 
<N  *i  CM 

o 
o 

C-J 

o 
o 

<M 

o 
CM 

o 
55 

ooo 

OOlfl 

O 

O 

ooo 
822 

Ol  <N  (N 

o 
os 

o 

lO 

o 

o 
o 

53 

O 

o 

o 

ooo 

ooo 

OS  OS  OS 

OS 

ooo 
ooo 
j.  o:  os 

o 
o 

CO 

o 

o 

OS 

o 
>« 

CS 

g   s 


S3 

fa 

ci  >>ci 
fa">fa 

T3 

a 

,2    s  a: 

co         fa 


13 

■■co 

r3  d  rt 

O 

-oo 

0  s  g3 

O 

5,oo 

O  i>  0) 

O 

faOO 

o 

C5Ju3 

all 

fa       0)       CO 


2 

i'0:i 
1—1 1—1 

CO 
CO 

CQ  CO"* 

cr.  t-co 

CO 
OS 

OS 

CO 
CM 

in  mi- 
ce coo 

>o 

OS"*— 1 

CO 

o 

CO 
CO 

co 

CO 

o 

O  COiO 

O 

\a  ia  >-o 

\a 

CO 

lO 

* 

COCOlO 

ea 

ooo 

lO 

lO 

-* 

co 

is 

CO  lO 

CO  CO  CO 

iO 

OiSffl 

o 

CO 

s 

«     ?    8 

o      o      o 
I-?     O     O 


-<*        CO  CM  CM 


si 

Si 


ft 


•43 

•  co 

•2 
:o 
:0 
d-g 

oft 


tj   Si 

O  0) 

^fto2 


o 


wso5 


racfa 


O    A3  flfe  ^ 
*»  .2  ^    S3 


GO. 

pa  +s^  S  d-* 


O  O        h 


fa 

C  :0 
If 


o 

ft  . 
c  - 


!   O 

fa  — 


^  °  £1 

o>^^: 
Cd    a    pq 

•J         l  -        CO 


I 


BIBLIOGEAPHY. 

Such  a  list  could  be  made  to  include  thousands  of  titles,  but  all  that 
is  intended  here  is  to  give  the  titles  to  the  more  important  and  easily 
obtained  works  on  clays  and  the  manufacture  of  clay  products. 

The  German  works  contain  much  that  is  of  importance  on  the  tech- 
nology of  clay-working,  and  many  of  them  can  be  obtained  at  reason- 
able rates. 

For  an  exhaustive  index  the  reader  is  referred  to  the  Bulletin  of  the 
U.  S.  Geological  Survey,  by  J.  C.  Branner,  given  below. 

The  articles  which  are  mainly  locality  reports  are  marked  a;  those 
dealing  largely  with  the  technology  alone,  b;  reports  treating  of  both 
are  marked  c. 

Barber,  E.  A.  Pottery  and  Porcelain  of  the  United  States.  Xew 
York,  1893.      (Historic.) 

Bischof,  C.     Die  Feuerfesten  Thone.     Leipzig,  1895  (b). 

Blue,  A.  Vitrified  Bricks  for  Pavements,  3d  Ann.  Kept.  Ontario 
Bureau  of  Mines,  p.  103.     Toronto,  1893  (b). 

Blatchley,  AY.  S.  Clays  of  Coal-bearing  Counties  of  Indiana,  Ind. 
Geol.  Surv.,  20th  Ann.  Kept.,  p.  24,  1896  (c). 

Bock,  O.     Die  Ziegelei-Industrie.     Leipzig. 

Branner,  J.  C.  Bibliography  of  Clays  and  the  Ceramic  Arts,  Bull. 
IT.  S.  Geol.  Surv.  No.  143,  1896. 

Chamberlin,  T.  C.  Geol.  of  Wisconsin,  vol.  II,  p.  235,  1877,  and  I, 
p.  668,  1883.     Describes  Milwaukee  brick  and  clay  (a). 

Cook,  G.  H.     Clays  of  Xew  Jersey,  Geol.  Surv.  X.  J.,  1878  (a). 

Cook,  R.  A.  Manufacture  of  Fire-brick  at  Mt.  Savage,  Md.,  Trans. 
Amer.  Inst.  Min.  Eng.,  vol.  XIY,  p.  698,  1886  (b). 

Cox,  E.  T.  Porcelain,  Tile  and  Potters'  Clays,  Ind.  Geol.  Surv., 
1878,  p.  154  (a). 

Davis,  C.  T.  Bricks,  Tiles  and  Terra  Cotta.  Philadelphia, 
1884,  second  edition  1889  (b). 

Dummler,  K.  Ziegel  und  Thonwaaren  Industrie  in  den  Yereinigten 
Staaten.     Halle,  1894  (b). 

Griffiths,  H.  H.     Clay  Glazes  and  Enamels.     Indianapolis,  1S95  (b). 

Hill,  R.  T.  Clays  of  the  United  States,  U.  S.  Geol.  Survey,  Mineral 
Resources,  1891,  p.  474  (a). 

Hofman  and  Demond.  Tests  on  the  Refractory  Character  of  Fire- 
clays, Trans.  Amer.  Inst.  Min.  Eng.,  vol.  XXIY,  p.  42,  1895  (b). 


_ 


BIBLIOGRAPHY.  151 

Holmes,  J.  A.  The  Kaolin  and  Clay  Deposits  of  North  Carolina, 
Trans.  Am.  Inst,  Min.  Eng.  XXV,  p.  929,  1896  (a). 

Irelan,  L.  Pottery,  9th  Ann.  Eept.  Cal.  State  Mineralogist, 
p.  240,  1890  (5). 

Johnson,  W.  I).  Clays  of  California,  9th  Ann.  Report.  Cal.  State 
Mineralogist,  p.  287,  1890  (a). 

Kerr,  W.  C.      Geology  of  North  Carolina,  vol.  I,  1875,  pp.  29G,  297. 

Ladcl,  G.  Clays  of  St.  Louis  County,  Mo.,  Bull.  Mo.  Geol.  Surv. 
No.  3,  1890  (a). 

Langenbeck,  K.      Chemistry  of  Pottery.     Easton,  189 G  (b). 

Lesley,  J.  P.  Kaolin  Deposits  of  Delaware  and  Chester  Counties, 
Pa.,  Ann.  Kept.  Pa.  Geol.  Survey,  p.  571,  1885  (c). 

Loughridge,  K.  H.  Clays  of  Jackson  Purchase  Kegion,  Kentucky, 
Kentucky  Geol.  Surv.,  p.  77,  1888  (a). 

Meade,  D.  W.  Manufacture  of  Paving  Brick,  Trans.  Amer.  Soc. 
Civ.  Eng.,  vol.  XXIY,  p.  553,  1893  (&). 

Orton,  Edward,  Jr.  Clays  and  Clay-working  Industries  of  Ohio, 
Ohio  Geol.  Survey,  vol.  VII,^part  I,  p.  69,  1893  (b). 

Periodicals : 

Brick  (monthly),  Chicago,  111. 
Brickbuilder  (monthly),  Boston,  Mass. 
Brickmaker  (bi-weekly),  Chicago,  111. 
Clay  (quarterly),  Willoughby,  O. 
Crockery  and  Glassware  Journal  (weekly),  N.  Y. 
Clay-worker  (monthly),  Indianapolis,  Ind. 
Paving  and  Municipal  Engineering,  Indianapolis,  Ind. 
|  Thoninclustrie  Zeitung,  Berlin,  Germany. 

Topfer-  und  Ziegler-Zeitung,  Berlin,  Germany. 

Phillips,  Wm.  B.  Eng.  Min.  Jour.,  XLII,  p.  326;  and  Jour.  Iron 
and  Steel  Industry,  1887,  No.  1,  p.  389  (c). 

Piatt,  F.  Test  of  Fire-Brick,  Pa.  Geol.  Survey,  Kept.  M.  M.,  p.  270, 
1879  (b). 

Pies,  LI.  Clays  of  United  States,  Mineral  Industrv,  1891,  vol. 
II  (c). 

Pies,  H.  Clays  of  Hudson  Kiver  Valley,  10th  Ann.  Kept,  of  N.  Y. 
State  Geologist,  1890  (c). 

Pies,  IL.  Clay  Industries  of  New  York,  Bull.  N.  Y.  State  Museum, 
vol.  Ill,  No.  12,"  1895  (c). 

Pies,  H.  Technology  of  Clay-working  Industry  and  Analyses  of 
Clays  of  U.  S.,  IT.  S.  Geol.  Surv.,  16th  Ann.  Kept.,  pt.  IV,  p.  523  (6). 

Pies,  H.  Pottery  Industry  of  United  States,  17th  Ann.  Kept.  U.  S. 
Geol.  Survey,  pt.  Ill,  p.  842  (&). 


\ 


152  CLAY    DEPOSITS    IN    NORTH    CAROLINA. 

Hies,  H.  The  Clays  of  Florida,  17th  Ann.  Kept.  U.  S.  Geol.  Sur- 
vey, pt.  Ill,  p.  871  (a). 

Ries,  H.     Clays  of  Alabama,  Bull.  Ala.  Geol.  Survey,  1897  (a). 

Ries,  H.  The  Clay-working  Industry  in  1896,  18th  Ann.  Rept. 
U.  S.  Geol.  Survey,  pt,  Y,  p.  1105,  1897  (c). 

Ries,  H.  The  Ultimate  and  Rational  analysis  of  Clays  and  their  rela- 
tive advantages,  Trans.  Amer.  Inst.  Min.  Eng.,  XXVIL 

Smith,  E.  A.  Clays  of  Alabama,  Ala.  Indus,  and  Sci.  Soc,  vol.  II, 
1892  (a). 

Smock,  J.  C.  Mining  Clays  in  New  Jersey,  Trans.  Amer.  Inst. 
Min.  Eng.,  Ill,  p.  211,  1874-75  (&). 

Smock,  J.  C.     Xew  Jersey  Clays,  ibid.,  vol.  YI,  p.  177,  1879  (a). 

Spencer,  J.  W.     Clays  of  Georgia,  Ga.  Geol.  Surv.,  p.  276,  1893  (a). 

Struthers,  J.  Le  Chatelier  Thermo-electric  Pyrometer,  School  of 
Mines  Quarterly,  vol.  XII,  p,  143,  and  vol.  XIII,  p.  221  (b). 

Wheeler,  H.  A.  Fusibility  of  Clays,  Eng.  and  Min.  Jour.,  XYII, 
p.  224,  1894. 

Wheeler,  H.  A.     Yitrifled  Paving  Brick.     Indianapolis,  1895. 

Wheeler,  H.  A.     Clays  of  Missouri,  Mo.  Geol.  Survey,  vol.  XI,  1896. 

Young,  Jennie  J.     Ceramic  Art.     Xew  York,  1878  (b). 

Zwick,  F.     Die  Ziegel  Industrie.     Leipzig,  1894. 


NDEX. 


PAGE 

Absorption  of  water  by  clays 42 

Air-drying  of  clays 26 

Alabama  clays,  silica  in 24 

Aleksieje w  cited 34 

Alkalies  in  clay 16, 17, 

advantage  of 

coloring  influence  of ,  in . .     18 

determination  of,  in  clay  27 

fixed  in  clay 

soluble  alkaline  compounds 

sulphates  as  fluxes 

insoluble       "        ""        "      

silicates  as  fluxes  —   

Aluminium  oxide  in  clay,  determination  of. .28 

Ammonia  in  clay 16 

Analyses  of  clays  (see  brick-clay,  fire-clay, 
pottery-clay,  pipe-clay  and  kaolin), 

142,149 

methods  of  making 27 

rational  analyses 9,  29,  30 

Asbury's  brickyard 125 

Auger  machine 97 

Asheville,  brick  clay  near —  104 

Baskerville,  Chas.,  analyses  by ... 9,  27 

quoted 27 

Bibliography 150 

Biltmore,  brick-clay  near 106 

Bikchof,  C,  quoted    24,35 

Blackburn,  pottery  industry  at  . . 76 

Bostick,  kaolin  near . 65 

Brick-clay  deposits  in  North  Carolina. .  .92, 102 

Brick  for  building 93 

effect  of  calcium  carbonate  on 21 

manufacture,  methods  of 94 

soft-mud  process  —  ....94 

stiff-  "  "        96 

dry-press      "        • 99 

Brick-clays  and  brick  manufacture 92 

Brick-clays,  general  characters  of 92 

effect  of  sand  on    93 

requisites  of 93 

analyses  of 103,104, 

105,  107, 108,  109,  110,  111,  112,  113, 
114,  115, 116,  117,  118,  119,  120,  121, 
122, 123, 124,  125,  126,  127,  128,  129, 
130,  132,  133,  134,  135,  136,  137,  138. 

preparation  of 94,  96, 100 

tempering 94,  96 

molding 95,  97,  101 

burning 95,  98, 101 

Brick-clay,  deposits  in  North  Carolina 102 

in  Bladen  county 102 

near  Prospect  Hall 102 


PAGE 

Brick-clay,  in  Bladen  County,  on  property 

of  Wm.  Whitted 102 

in  Buncombe  county  — 104 

Penniman's  clay  bank,  near 

Emma    104 

near  Asheville  and  Biltmore.  1C6 

near  Fletcher 106 

Buncombe  Brick  Co 106 

in  Burke  Co 107 

near  Morganton 107 

in  Cleveland  Co 108 

near  Grover  108 

in  Cumberland  Co 110 

near  Fayetteville — 110 

in  Forsyth  Co HI 

near  Bethania Ill 

Carter  &  Shepherd's  clay  b'k.113 

in  Gaston  Co 113 

near  Mt.  Holly 113 

in  Guilford  Co 114 

near  Greensboro 114 

Dean's  brickyard     115 

Kirkpatrick's  brickyard 115 

Watson's  brickyard 115 

in  Halifax  Co 116 

near  Roanoke  Rapids 116 

"     Weldon 119 

"     Halifax 119 

in  Harnett  Co   ...  ...  119 

near  Spout  Springs 119 

in  Jackson  Co 121 

near  Sylva 121 

in  Martin  Co 122 

near  Williamston   122 

in  Mecklenburg  Co 122 

near  Charlotte 122 

Cecil's  yard 123 

Houser's  yard 123 

Sassamon's  yard 123 

Shuman's  deposit 124 

Asbury's  brickyard 125 

in  Richmond  Co .   •   125 

near  Rockingham 125 

in  Robeson  Co 12& 

near  Red  Springs  . .   126 

in  Rowan  Co 127 

near  Salisbury 127 

in  Surry  Co 128 

"    near  Elkin 128 

in  Union  Co 129 

near  Monroe 129 

Shute's  clay-bank 129 

in  Wake  Co 130 


154 


INDEX. 


Brick-clay,  in  Wake  Co.,  near  Raleigh 130 

in  Wake  Co.,  Penitentiary  brick 

yard    130,131 

Green's  property 131 

Caraleigh  Mills  Co 131 

in  Wayne  Co 131 

near  Goldsboro 131 

Goldsboro  Brick  and  Tile  Co.131 

Weil  &  Bros,  yard    133 

in  Wilkes  Co 134 

Smoak's  yard 134 

in  Wilson  Co 136 

near  Wilson 136 

Lucas  property 137 

BrindeFs  kaolin  deposit  62 

Buncombe  Brick  Co  106 

Burke  Co.,  pottery  industry  in 75 

brick-clays  in 107 

Burning  brick 94,95,96,98,101 

updraf  t  kilns 98 

continuous  kilns 98 

Calcium  carbonate  in  clay 21 

effect  on  brick 21 

Calcium  oxide  in  clay 28 

Caraleigh  Mills,  brick-clay  at 130 

Carbonate  of  iron  as  source  of  iron  in  clays. .  19 

Carbonic  acid,  action  on  feldspar  12 

Carter  and  Shepard's  clay  bank   113 

Catawba  county,  pottery  industry  in 76 

Cecil's  brickyard 123 

Clay  substance 14 

Clay,  absorption  of  water 42 

absorbing  lime 22 

alkalies  in 16 

ammonia  in 16 

analyses  of 142-149 

bases  in 11, 15, 16,  17,  18,  20,  21,  22,  23 

brick  (see  brick-clay) 92 

chemical  analj'sis  of 27 

chemical  properties  of 15 

china 50 

character  of  for  paving-brick 139 

color  of,  unburned  20 

color  of 43 

composition  of  (see  analyses) 11 

compounds  of  iron  in 18,19,20 

comparison    of,    from     Wilson    and 

Wayne  counties , 138 

Cretaceous  and  Tertiary 12 

defined 11 

density  of 43 

effect   of   calcium    carbonate    in,   on 

brick 21 

Forsyth  county    Ill 

near  Fayetteville 110 

fire-shrinkage  of   35 

fire-clay  (see  fire-clays,  p.  155). 

fluxing  impurities  in 15-23 

fusibility  of 36 

geology  and  geography  of,  in  N.  C 44 

hornblende  in 12 

impurities  in 15 

lime  in 15,20 

magnesia  in 15,  23 


Clay,  non-fluxing  impurities  in 23 

origin  of n 

organic  matter  in 25 

pipe-clay  in  North  Carolina , 86 

plasticity  of   25.  26.  33.  34 

preparation  of 54,94,96,100 

properties  of 11, 14 

pure,  composition  of   11, 14 

purity  of,  depends  on 12 

physical  properties  of 33,  42 

pottery  clays  in  N.  C 71 

pottery  clay,  requisites  of 72 

removing  lime  from 21 

residual  clays  (see  residual)   ....  12,  44, 92 

substance 14 

sedimentary 12, 13,  46,  92 

shrinkage  of 35 

silica  in 24 

silica,  two  classes  of ,  in 24 

silica,  free,  in 24 

silica  in  Alabama  clays 24 

"      "  North  Carolina 24 

slaking  of 42 

sulphuric  acid  in 15 

taste  of 43 

tempering  the 94,  96 

temperature  at  which  clay  fuses 37 

tensile  strength  of 34,35 

texture  of  42 

titanium  in 24 

variation  in  composition  of 13, 14 

water  in 26 

working  industries 48 

Clay,  brick,  near  Asheville 106 

Bethania .111 

Biltmore 106 

Charlotte 122 

Elkin  128 

Fayetteville 110 

Fletcher 106 

Goldsboro 131 

Greensboro 114 

Grover 108 

Halifax 119 

Monroe ..129 

Morgan  ton 107 

Mount  Holly 113 

Prospect  Hall 102 

Raleigh 130 

Red  Springs 126 

Rockingham 125 

Roanoke  Rapids 116 

Salisbury 127 

Spout  Springs —   119 

Sylva 121 

Weldon 119 

Williamston 122 

Wilson 136 

Wilkesboro 134 

Clays  from   Wilson   and  Wayne  counties 

compared 138 

Clay  deposits,  geology  and  geography  of 

North  Carolina.   44 

Cleveland  cou  nty ,  fire-clays  in 81 


INDEX. 


155 


Cleveland  county,  brick-clays  in 108 

Cook,  Prof.  G.  H.,  quoted 33 

Continuous  kilns .   ...98 

Coal  mixed  with  clay  in  burning  brick 96 

Color  of  clays 43 

Compounds  of  iron  in  clay  18 

Combined  water  in  clay 26 

Cramer  cited 25 

Cremiatschenski  cited 34 

Deans'  brickyard    115 

Density  of  clays 43 

Deposits  of  kaolin  in  North  Carolina 58 

Dry-press  process    99 

preparation  of  clay  for    100 

molding-  in 101 

burning  the  brick  in 101 

Determination  of  moisture  in  clay 27 

water         "      ""     27 

alkalies      "      "     27 

silica  "      "    27,28 

iron  sesquioxide 28 

aluminium  oxide 28 

calcium  "       28 

magnesium    "      28 

insoluble  residue 28 

titanic  oxide  — 29 

sulphur   29 

ferrous  oxide  29 

rational  analyses 29 

Distribution  of  the  kaolins 50 

Elkin,  brick-clay  near 128 

Emma,  Penniraan's  clay  bank  near    104 

Fayetteville,  brick-clay  near  110 

Feldspar,  orthoclase  11, 17, 18 

action  when  fused 16 

alkalies  in 16,17,18 

weathering  of 12 

Ferric  oxide  in  clay .     ..19 

percentage  desirable 20 

Ferric  silicate  in  clay,  effect  of 19 

Fire-brick,  manufactured 48 

Fire-clays 80 

characteristics  of 80 

analyses  of 81,  82,  83,  84,  85 

in  Cleveland  Co 81 

near  Grover  81 

in  Guilford  Co 83 

Pomona  clay-bank  83 

Woodroffe  clay-bank 85 

Fletcher,  brick-clay  near 106 

Fluxes,  in  clay,  per  cent.  of,16, 17, 18, 19, 20,  21, 22 

Fluxing  impurities  in  clay 15-23 

Forsyth  county,  brick-clays  in Ill 

Fusion  of  clay,  incipient 36 

stages  of   36 

temperature  of 37 

Fusion  temperatures,  table  showing 39-41 

Fusibility  of  clay 36 

Gaston  county,  brick-clay  in 113 

Geology  and  geography  of  North  Carolina 

clays  44 

Goldsboro,  brick-clays  near    131 

Goldsboro  Brick  and  Tile  Co  131 

Greensboro,  brick-clay  near 114 


Greensboro  Brick  and  Tile  Co.'s  yard 114 

Green's  property    131 

Grover  Brick  Company 81 

Grover,  brick-clays  near 108 

Gypsum  in  clays 22 

Guilford  county,  fire- clays  in 83 

Pomona  clay-bank 83 

Woodroffe  clay-bank  — 85 

pipe-clays  in 88 

Pomona  Terra  Cotta  Co.'s 

works    88 

brick-clay  in 114 

Halifax  county,  clay  in 116 

brick-clays  near 119 

Harris  Clay  Co 59 

Harnett  county,  brick-clays  in 119 

Hematite,  an  impurity  in  clay 18,  19 

Houser's  brickyard 123 

Holmes,  J.  A.,  cited 46 

Hornblende  in  clays 23 

Hygroscopic  water  in  clay 26 

Ignition,  loss  on,  in  clay 27 

Industry,  clay  working  in  North  Carolina. .  .48 

pottery,  The 71 

Impurities  in  clay .  .15, 16, 17, 18, 19,  20,  21,  22,  23, 

24,25 

fluxing  impurities 16 

non-fluxing  impurities 23 

in  residual  clay 12 

Infusibility  of  kaolinite 15 

Insoluble  residue,  determination  of 28 

Iron  compounds  in  clay 18, 19,  20 

Iron  sesquioxide,  determination  of 28 

Iron,  a  coloring  agent 19,  20 

percentage  permissible  in  clay 20 

in  N.  C.  kaolins   20 

sources  of,  in  clay 18 

Incipient  fusion  of  clay  — 36 

Jackson  county 58 

brick-clay  in  — 121 

kaolin  in 58,  59,  60,  61,  62 

Jolly-wheel —  74 

Kaolin,  analyses  of 59,  61, 62,  63,  65,  67,  68,  69 

Kaolin,  Bostick's  Mills 65 

china  clay   50 

comparisons  of  North  Carolina  with 

foreign  ones 69 

composition  of 52 

distribution  of 50 

fluxes  in 16 

Harris  Clay  Co.'s  mine 59 

iron  in 53 

Jackson  county 58 

mineralogical  character  of 50 

mining  of 53 

Montgomery  county 64 

North  Carolina  Mining  and  Mfg.  Co.'s 

mine    58 

preparation  of 54 

plasticity  of,  inci-ease  by  grinding..  15 

properties  of 51 

Richmond  county 65 

Springer's  pit 61 

Steele's  deposit 65 


\ 


156 


INDEX. 


Kaolin,  Sylva 58 

Troy 64 

uses  of,  North  Carolina 68 

Wests  Mill  62 

Webster 59 

Kaolinite,  composition  of 11, 12 

described    15 

formation  of 11 

origin  of 11 

refractoriness  of 15 

Kilns 98 

up-draf  t 98 

continuous 98 

Kirkpatrick's  brickyard 115 

Langenbeck  cited 59 

Lime,  compounds  of,  in  clays 20,  21,  22 

absorption  of  into  clays 22 

as  carbonate,  effect  on  clay 21 

as  silicate,  ik       "      "    21 

as  sulphate,        "       "     "     21,22 

effect  on  brick 21 

in  North  Carolina  clays     23 

Limonite,  a  frequent  impurity  in  clays.  .18, 19 

Lincoln  county,  pottery  industry  in 77 

Lincolnton ,  pottery  industry  near  77 

Lithia  in  clays 16 

Lucas,  brickyards  of    137 

Macon  county,  kaolin  in 62 

Magnesia,  origin  of,  in  clay 23 

in  clays. 23 

in  North  Carolina  clays 23 

Magnesium   carbonate 23 

oxide  in  clay,  determination  of  .28 

sulphate 23 

Manufacture  of  brick 92 

of  stoneware 73 

of  sewer-pipe  and  tiles 86 

of  paving-brick 139,  140 

Martin  county,  brick-clay  in 122 

McDowell,  Manly,  pottery  clay 75 

Measurement  of  temperature 38 

Mecklenburg  county,  brick-clay  in 122 

Methods  employed  in  making  clay  analyses. 27 

Methods  of  brick  manufacture 94 

soft-mud  process 94 

stiff-mud  process 96 

semi-dry  press 94, 101 

dry-press 99 

Mineral  impurities  in  clay  15 

Mining  of  kaolin 53 

Moisture  in  clays —   .  26 

hygroscopic 26 

chemically  combined 26 

determination  of 27 

Molding  brick .   94,  95,  97, 101 

Monroe,  brick-  clays  near    129 

Montgomery  county,  kaolin  in 64 

Morganton,  pottery  industry  near 75 

brick-clays  near 107 

Mount  Holly,  brick-clays  near ]  13 

Non-fluxing  impurities  in  clay 23 

North  Carolina  clay-working  industry,  The. 48 

deposits  of  kaolin  in  58 

pottery  clays  in 71 


North  Carolina  fire-clays  and  pipe-clays  in.  .80 

pipe-clays  in 86 

brick-clay  deposits  in 102 

clays,  silica  in  24 

Olschewsky  quoted 34, 140 

Organic  matter  in  clays   25 

effect  of,  on  clay 25 

Origin  of  clays u 

Orton,  E.,  Jr.,  cited    84,  140 

Oxides  in  clay 15, 18 

Oxygen,  a  weathering  agent 12 

Paving  brick,  manufacture  of  ....  139,140,141 

analysis  of  clay  for  139 

character  of  clay  requisite  for 
139 

kilns  for 140. 141 

Penitentiary  yard,  Raleigh,  brick-clay  at  .130 

Penniman,  clay  bank,  near  Emma 104 

Percentage  of  iron  admissible  in  clay 20 

in  N.  C.  kaolins 20 

Physical  properties  of  clay 33,  42 

Pipe-clays  in  North  Carolina 86 

analyses  of   89,90 

methods  of  manufacture.  .86,  87,  88 

in  Guilford  county 88 

Pomona  Terra  Cotta  Co's  works.  88 

requirements  of 86 

tensile  strength  of 86 

Plasticity  in  clays 34 

in  kaolinite  increased  by  grind- 
ing    15 

effect  of  organic  matter  on 25 

Poe  &  Bros,  yard 110 

Pomona  Terra  Cotta  Co 83,  88 

Sewer-pipe  and  Brick  Co 86 

Potash  in  clay 11,  15, 16,  18 

Pottery  clays  in  North  Carolina 71 

Pottery  clay,  requisites  of 72 

analyses  of 75.  76,  77,  78,  79 

Burke  county  75 

Blackburn 76 

Catawba  county    76 

Cowles,  Calvin 79 

Lincoln  county 77 

near  Lincolnton 77 

Rhodes, T 77 

Wilkes  county 78 

Wilkesboro 78 

Pottery  industry,  The    71 

in  Burke  county 75 

at  Blackburn .'  —  76 

in  Catawba  county .76 

in  Lincoln  county 77 

near  Lincolnton ...  77 

near  Morganton 75 

in  Wilkes  county 78 

in  Wilkesboro 78 

Powhatan  Clay  Mfg.  Co 81,  82 

Preparation  of  clay  for  bricks 94,  96, 100 

fire-clay 80,  81 

kaolin 54,  55,  56,  57,  58 

pipe-clay 86 

pottery-clay 72 

clay  for  paving-bricks 140 


timh  Carolina  Sfate  library 
Raleigh 


INDEX. 


157 


Pressed  brick 

Properties  of  kaolin 
Prospect  Hall  clays 
Pyramids,  Seger's  ... 

Pyrite  in  clay .. 

Pyrometers 


49 

51 

.102,103,104 

38 

18,19 

38 


Thermo-electric,  The 38 

Seger's  pyramids    38 

Purity  of  clay  depends  on 12 

Raleigh,  brick  clays  near 130 

Rational  analysis  of  clay,  The 30 

method  of  making 29 

practical  bearing  of 31 

Refractoriness  of  clay 37 

Requisites  of  a  brick-clay 93 

fire-clay  . .   80 

pipe-clay 86 

Red  Springs,  brick-clay,  near 126 

Residual  clays 12,44,92 

composition  of 45 

impu  rities  in 12 

Residue,  insoluble,  determination  of  ..   28 

Rhodes  property,  pottery  clay 77 

Richmond  county,  kaolin  in 65 

brick-clay  in 125 

Roanoke  Rapids,  brick-clay  near 116 

Rockingham,  brick-clay  near .125 

kaolin  near 65 

Roberdell,  brick-clay  at 125 

Robeson  county,  brick-clay  in    126 

Rowan  county,  brick-clay  in 127 

Salisbury,  brick-clay  near 127 

Sand,  effect  of,  on  brick-clays 93 

Sassamon's  brickyard 123 

Sedimentary  clays 46,  92 

Seger,  quoted 20,  22.  52 

Seger's  pyramids 38 

•>  fusion  temp,  ratures  of  39,  40,  41 

Semi-dry-press  process 94, 101 

Sewer-pipe 86 

method  of  manufacture.   ..  86,87, 
88,91 

Pomona  Terra  Cotta  Co 88 

Shales,  used  as  clays 12,13 

metamorphism  of 13 

Shrinkage  of  clays 35,  36 

Shute's  clay-bank 129, 130 

Shuman's  deposit 124 

Silica,  determination  of  in  clays 27 

in  clays 24 

effects  of  on  clays 24 

Silicates,  in  clay 11 

of  iron  in  clay 18, 19 

Slaking  of  clays 42 

Smoak'syard  134 

Soda  in  clay 15,16,17 

Soft-mud  process    94 

tempering  the  clay 94 

molding  the  brick 95 


Soft-mud  burning 95 

Spout  Springs,  brick-clay  near 119 

Springer  clay-pit 61 

Stiff-mud  process 96 

tempering  the  clay  96 

molding 97 

burning 98 

Stoneware  manufacture  73,  74,  75 

Sulphur  in  clay,  determination  of 29 

Sulphates  as  a  source  of  iron  in  clays ....  18, 19 
Sulphides  "   "      "  "      "      "      "       ...  18,19 

Sulphuric  acid  in  clays 15 

Surry  county,  brick-clay  in 128 

Sylva,  brick-clay  near  .   121 

Table  of  variations  in  clay  substance 52 

Taste  of  clays 43 

Temperature  at  which  clay  fuses 37 

measurement  of 38 

Tempering  clay,  soft-mud  process 94 

stiff-mud        "        96 

Tensile  strength  of  clays 34 

Terra-cotta  ware 88 

Company,  Pomona 88 

Texture  of  clays 42 

Thermo-electric  pyrometer,  The 38 

Tiles,  manufacture  of 86 

Titanium  in  clay 24 

as  a  flu  x 25 

Titanic  oxide,  determination  of 29 

Union  county,  brick-clay  in 129 

Uses  of  North  Carolina  kaolin 68 

Variations  in  clay 13,14 

Variation    in    clay   substance,   etc.,   table 

showing 52 

Viscosity  of  clay 36 

Vitrification  of  clay 36 

Wake  county,  brick-clays  in 130 

Water  in  clays 26 

absorption  of,  by  clays 42 

hygroscopic 26 

combined 26 

Watson's  brickyard ...  115 

Wayne  county,  brick-clays  in 131 

Weathering  of  feldspar .12 

Webster,  kaolin  near    59 

Weil  &  Bros,  brickyard 133 

Weldon,  brick-clays  near 119 

Wests  Mill,  kaolin  near 62 

WT heeler  cited 34,37,139 

Whitted,  Wrilliam,  clay  on  land  of 102 

Wilson  county  clays  136 

brick-clays  in 136 

Wilson,  brick-clays  near 136 

Wilkes  county     "  "     in 134 

pottery  industry  in 78 

Wilkesboro,  pottery  industry  near 78 

brick-clays  near ..134 

Williamston 122 


\ 


60 


STATE  LIBRARY  OF  NORTH  CAROLINA 


3  3091  00772  7852