MINERAL  RESOURCES  OF  THE  BIGHORN   BASIN. 
By  Cassius  A.  Fisher. 
COAL. 
General  description. — Coal  is  the  principal  mineral  resource  in  the  sedimentary  formations 
the  Bighorn  Basin.  It  occurs  mainly  in  the  so-called  Laramie  formation,  although  on  the 
t  side  of  the  district  a  coal,  said  to  be  of  good  quality,  is  found  in  the  upper  part  of  the 
lorado  formation,  and  on  No  Wood  Creek,  12  miles  southeast  of  Bonanza,  a  deposit  of  coal 
nined  from  the  Cloverly  formation.  The  coal  is  found  at  various  horizons  throughout  the 
jaramie  "  formation,  but  the  most  persistent  beds  of  workable  thickness  are  in  a  basal  mem- 
r  of  this  formation,  or  possibly  in  lower  beds.  Coal  is  of  widespread  distribution  within  the 
ea  occupied  by  the  Laramie  formation.  The  greatest  development,  however,  is  found  in 
aces  where  the  larger  streams  expose  the  coal  measures.  Here  the  most  favorable  condi- 
ms  exist  for  locating  mines,  and  the  increased  settlement  of  the  irrigated  valleys  along  the 
earns  affords  a  local  market  for  the  coal.  A  detailed  description  of  the  coal  deposits  in 
e  various  districts  where  the  principal  development  has  taken  place  has  already  been 
blished,  a  but  since  this  investigation  was  made  several  new  mines  have  been  opened  and 
jrief  account  of  these  is  here  given. 
Cody  Coal  Company's  mine. — During  the  winter  of  1904  the  Cody  Coal  Company  opened 
mine  on  the  north  side  of  Shoshone  River,  about  3  miles  east  of  Cody  station.  The  coal 
curs  about  1,500  feet  above  the  base  of  the  Laramie  formation,  in  beds  dipping  at  an  angle 
45°  E.  It  is  about  4$  feet  thick  and  is  apparently  of  good  quality,  although  no  analysis 
the  product  is  available.  The  opening  of  this  bed  is  in  the  face  of  the  bluffs  about  30  feet 
ove  the  railroad,  so  that  the  coal  can  be  loaded  for  shipment  at  a  small  expense  when  the 
w  sidetrack  now  being  built  is  completed.  The  mine  is  well  timbered  and  preparations 
e  being  made  for  extensive  development.     A  section  of  the  deposit  is  as  follows: 
Section  at  Cody  Coal  Company's  mine,  Cody,  Wyo. 
Dark  sandy  clay.  Feet. 
Coal 4 
Coaly  shale 2 
Dark  sandy  clay 8 
Gray  massive  sandstone 20 
Arrangements  are  now  being  made  by  another  company  to  mine  coal  at  the  same  horizon 
q  the  south  side  of  Shoshone  River. 
Silver  Tip  mine. — The  deposit  on  Cottonwood  Creek,  on  the  north  side  of  the  divide 
etween  Clark  Fork  and  Shoshone  River,  has  been  prospected  at  several  places,  but  the  prin- 
ipal  opening,  the' Silver  Tip  mine,  is  in  sec.  29,  T.  58,  R.  100.  Here  considerable  coal  has 
een  taken  out  for  the  last  three  years,  chiefly  to  supply  the  ranch  trade  of  Clark  Fork  Valley, 
he  total  thickness  of  the  bed  is  5  feet,  including  two  partings  of  impure  coal  and  a  thin 
lyer  of  soft  light-colored  clay.  The  main  entry  is  driven  in  about  125  feet  from  the  outcrop 
nd  throughout  this  distance  the  character  of  the  coal  appears  to  be  uniform.     An  analysis 
o  Fisher,  Cassius  A.,  Coal  of  the  Bighorn  Basin:  Bull.  U.  S.  Geol.  Survey  No.  225,  1904.  p.  345. 
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