186        CONTRIBUTIONS  TO  ECONOMIC  GEOLOGY,  1907,  PART  II. 
Section  of  coal  beds  in  NE.  \  NW.  \  sec.  35,  T.  9  S.,  R.  23  E.  {Montana). 
Upper  bed : 
Coal. 
Clay. 
Coal. 
Ft.    in. 
Total  coal. 
Middle  bed: 
Coal 
Lower  bed : 
Bands  of  shale  and  coal;  not 
workable.  Thickest  coal, 
8  inches. 
Ft. 
3 
in. 
11 
In  the  southern  part  of  the  field  the  coal  beds  are  thinner,  as  shown 
by  the  following  section,  which  is  typical  of  that  part  of  the  field: 
Section  of  coal  beds  in  sec.  5,  T.  57  N.,  R.  99  W.  (Wyoming). 
Ft.      in. 
Sandstone,  tawny,  strong 5 
Shale,  sandy,  carbonaceous 10 
Coal 6 
Shale,  carbonaceous 3 
Coal,  bony,  with  carbonaceous  shale  partings 2 
Shale,  carbonaceous 1 
Coal 1      3 
Coal,    bony   in   places;  mostly   carbonaceous   shale;  other 
places  largely  coal;  nowhere  workable 6 
Coal 10 
Shale 5 
Total  coal. 
Silvertip  mine. — The  Silvertip  mine,  which  is  on  the  west  side  of 
the  field,  about  2  miles  south  of  the  State  line,  is  the  only  producing 
mine  in  the  field.  It  consists  of  a  slope  about  300  feet  long,  from 
which  two  rooms  have  been  turned  off  to  the  left.  The  total  produc- 
tion up  to  July,  1907,  is  reported  to  be  only  500  tons,  but  the  size  of 
the  workings  indicates  a  much  larger  production.  The  coal  is  mined 
by  one  or  two  men  during  part  of  the  year,  especially  in  winter, 
hoisted  from  the  mine  by  a  gasoline  engine,  and  hauled  in  summer 
time  by  wagons  to  Garland  and  to  the  camps  of  the  Reclamation 
Service  at  Corbett,  Wyo.,  where  it  is  sold  for  $5  to  $6  per  ton.  The 
following  are  sections  at  this  mine: 
Sections  of  coal  bed  at  the  Silvertip  mine,  in  NW.  \  SE.  \  sec.  25,  T.  58  N.,  R.  100  W. 
( Wyoming) . 
MAIN  ENTRY 
Shale. 
Coal 
Shale 
Coal 
Shale 
Coal 
Base  not  exposed . 
Ft.    in. 
1     3 
2i 
1 
2     1 
Total  coal 4    0 
FIRST  ROOM  ON  LEFT  OF  ENTRY. 
Ft.    in. 
Coal 8 
Clay 1 
Coal 2 
Bone 2 
Coal 8 
Talcose    material;  white,  greasy, 
crystalline,  granular,  soft 
Coal .' 4 
Bone 2 
Coal,  good,  with  three  or  four  dis- 
continuous ^-inch  films  of  clay.     2     1 
Total  coal   3  Hi 
