ILLUSTRATIONS. 
Pago. 
Plate  I.  Map  showing  location  of  Snake  River  gold  placers  in  a  portion  of 
Uinta  County,  Wyo 76 
II.  Map  showing  location  of  placer  claims  along  Snake  River  in  the  vicin- 
ity of  Minidoka,  Idaho 78 
III.  Geologic  ma ]>  of  upper  Coal  Creek  Valley  and  vicinity.   Rio  Blanco 
County,  Colo 112 
IV.  Map  of  parts  of  Edaho,  Wyoming,  and  Utah,  showing  localities  of  upper 
( Jarboniferous  rocks  containing  phosphate  beds 450 
Fig.  1.  Index  map  showing  position  of  mining  camp-'  in    Philipsburg  quad- 
rangle. Montana 32 
2.  Sketch  plan  of  the  Granite-Bimetallic  lode.  Philipsburg  quadrangle, 
Montana 39 
3.  Generalized  section  of  <  Sranite  vein,  Philipsburg  quadrangle.  Montana. .         42 
4.  Granite  block  surrounded  andcul  by  coarsely  crystalline  calcite,  quartz, 
pyrite.  and  chalcopyrite,  Cable  mine,  Philipsburg  quadrangle,  Mon- 
tana         48 
5.  Economic  map  of  the  Hart  ville  uplift .  Laramie  County,  Wyo 192 
(i.  Sketch  ma))  of  Gila  River  alum  deposits 218 
7.  Map  showing  distribution  of  Portland  cemenl  raw  materials  in  vicinity 
of  Newcastle,  Wyo 233 
8.  Map  showing  location  of  Cheyenne  and  Newcastle,  Wyo..  in  relation  to 
established  Portland  cemenl  plants  and  transconl  inental  railroads. . .       240 
9.  Sketch  map  showing  line  of  outcrop  of  gypsum  bed.  northwestern  New 
Mexico 261 
10.  Map  showing  exposures  of  Cretaceous  rocks  in  Georgia 305 
11.  Map  of  Cheltenham  district  and  vicinity,  St.  Louis,  Mo 315 
12.  Map  of  South  Mountain  in  the  vicinity  of  Mount   Holly  Springs,  Pa., 
showing  clay  mines  and  rock  formations 327 
13.  Map  showing  areas  in  North  Carolina  in  which  mica  has  been  mined 402 
14.  Section  across  pegmatite  at  Thorn  Mountain  mine,  Macon  County,  N.  C  .       411 
15.  Pegmatite  2$  feet  thick  near  Wayah  Bald  mine,  Macon  County,  X.  C 413 
16.  Section  of   pegmatite    at  mica  prospect    near  Chink    Knob.  Jackson 
County,  N.  C 416 
17.  Section  of  pegmatite  at  Adams  mine,  1|  miles  southeast  of  Webster, 
Jackson  County,  N.  C 417 
18.  Sketch  section  2  miles  northeast  of  Cokeville,  Wyo.,  on  north  side  of 
Smiths  Fork 456 
19.  Section  of  Carboniferous  strata  on  north  side  of  Montpelier  Creek,  Idaho  .        158 
20.  Typical  section  of  lower  portion  of  phosphate  series,  Montpelier,  Idaho . .       459 
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