bansomb.]  COEUR   D'ALENE    DISTRICT,  TDAHO.  293 
lower  levels  are  worked  through  a  winze.  The  Tiger-Poor  man  and 
Hecla mines  arc  operated  through  shafts  in  the  tow  n  of  Burke.  These 
workings  are  respectively  1,800  and  600  feet  deep.  The  Standard- 
Mammoth  mine  has  two  long  cross-cut  adits,  the  Campbell  tunnel, 
running  nearly  north  from  a  point  on  Canyon  Creek  just  below  Mace, 
and  the  No.  6  tunnel,  running  nearly  northeast  from  a  point  on 
the  creek,  3,000  feet  west  and  about  150  feet  below  the  Campbell  adit. 
From  the  end  of  the  Campbell  tunnel,  an  underground  shaft  or  winze 
gives  access  to  5  levels,  the  lowest  being  1,050  feet  below  the  adit  level, 
or  about  2,000  feet  below  the  apex  of  the  vein.  The  main  adit  of  the 
Helena-Frisco  mine  is  a  south  crosscut  from  Canyon  Creek  near 
Gem,  at  the  end  of  which  is  a  shaft  1,400  feet  deep,  connecting  with  7 
levels.  The  main  adit  of  the  Hercules  mine  is  on  Tiger  Peak,  about 
1|  miles  north  of  Burke  and  about  1,500  feet  above  the  bed  of  Canyon 
Creek.  This  mine  as  yet'  produces  no  concentrates,  the  crude  ore 
being  hauled  by  wagons  to  the  railroads  at  Burke. 
It  appears  from  the  foregoing  that  the  mines  working  below  the 
main  canyon  bottoms  of  the  district  are  the  Tiger-Poorman,  Heclaj 
Standard -Mammoth,  and  Helena  Frisco.  Of  these,  the  Tiger-Poor- 
man, 1,800  feet,  is  the  deepest. 
The  lead-silver  mines  as  a  rule  are  equipped  with  excellent  machin- 
ery and  are  operated  in  a  first-class  and  substantial  manner. 
Structural  features  of  the  deposits. — Most  of  the  lead-silver  de- 
posits in  the  Coeur  d'Alene  district  are  metasomatic  fissure  veins. 
They  are  generally  tabular  deposits,  formed  partly  by  the  filling  of 
[>pen  spaces,  but  largely  by  replacement  along  zones  of  Assuring  or 
of  combined  Assuring  and  shearing.  The  type  is  best  exemplified 
jy  the  Canyon  Creek  and  Mullan  groups  of  mines.  The  deposits 
worked  in  the  mines  at  Wardner  have  different  forms  from  those 
of  Canyon  Creek  and  Mullan,  but,  broadly  regarded,  fall  into  the 
same  class.  The  ore  bodies  of  the  Granite  mine  also  present  some 
exceptional  features,  which  will  be  adverted  to  later. 
The  general  strike  of  the  lodes  is  northwestward.  In  the  Canyon 
Creek  and  Mullan  groups  the  prevailing  strike  is  about  N.  70°  W., 
with  local  variations  from  N.  55°  W.  to  west.  At  Wardner  the 
Bunker  Hill  and  Sullivan-Last  Chance  lode  strikes  N.  42°  to  45°  W. 
With  the  exception  of  this  lode,  which  dips  toward  the  southwest  at 
in  angle  of  38°,  and  the  Sierra  Nevada  lode,  which  in  places  is  almost 
lorizontal,  the  lodes  are  nearly  vertical.  The  Standard-Mammoth  and 
Hecla  dip  north-northeast  at  an  angle  of  about  85°.  The  Tiger- 
Poorman,  Hercules,  and  Helena-Frisco  have  generally  south-south- 
vest  dips  ranging  from  75°  to  nearly  vertical,  while  the  Morning  and 
iold  Hunter  lodes  are  practically  vertical. 
While  the  fissures  appear  to  have  been  opened  originally  by  fault- 
