bansomh.]  COEUR    D'ALENE    DISTRICT,  IDAHO.  291 
These  three  classes  of  deposits  are  fairly  distinct  in  their  geo- 
graphical distribution.  The  principal  lead-silver  deposits  occur  in 
(he  portion  of  the  district  drained  by  the  South  Fork  of  the  Coeur 
d'Alene  River  and  its  tributaries.  They  fall  into  three  main  groups, 
one  near  Wardner,  one  near  Mullan,  and  one  near  Burke.  The 
principal  gold  deposits  are  found  in  the  country  drained  by  the 
North  Fork,  particularly  by  Prichard  and  Beaver  creeks.  The  cop- 
per deposits  are  apparently  confined  to  the  corner  of  the  district 
lying  southeast  of  a  northeast-southwest  line  drawn  through  the 
town  of  Mullan. 
The  geological  distribution  of  the  ore  deposits  is  of  a  more  definite 
character  than  might  have  been  expected  from  the  lack  of  lithological  i 
contrast  in  the  thick  series  of  the  Coeur  d'Alene  sediments.  The  j 
gold  veins,  so  far  as  known,  occur  only  in  the  Prichard  slate,  the 
oldest  formation  in  the  region.  These  slates  constitute  the  prevail- 
ing rock  along  Prichard  Creek  from  Eagle  to  Thompson  Pass  on 
the  main  divide.  The  principal  gold-quartz  veins  occur  in  this 
area,  the  most  productive  being  between  Murray  and  Littlefield. 
Another  area  of  Prichard  slate  extends  along  the  South  Fork  from 
Osburn  past  Kellogg,  and  contains  the  gold-quartz  veins  worked  in 
early  days  on  Elk  Creek. 
The  principal  lead-silver  deposits  are  in  the  Burke  formation  j 
which  overlies  the  Prichard,  and  which,  as  already  described,  is  pre- 
vailingly a  sericitic  quartzite.  Probably  over  75  per  cent  of  the  lead- 
silver  ore  mined  comes  from  this  formation.  The  remainder  is 
derived  from  the  lower  beds  of  the  Revett  quartzite,  from  the  more 
slaty  and  calcareous  Wallace  formation,  perhaps  in  part  from  the 
St,  Regis  formation,  and  from  the  upper  part  of  the  Prichard  forma- 
tion, which  is  separable  merely  by  a  rather  arbitrary  plane  from  the 
Burke  formation  into  which  it  really  grades. 
The  only  productive  copper  deposit  in  the  district  occurs  in  the 
Revett  quartzite,  although  a  number  of  copper  prospects  have  been 
Dpened  in  the  Wallace  and  St.  Regis  formations. 
LEAD-SILVER   DEPOSITS. 
Mines. — The  principal  companies  operating  in  the  Coeur  d'Alene 
istrict   on  lead-silver  ores  are  the  Federal  Mining  and   Smelting 
Company,  owning  the  Tiger-Poorman  mine  at  Burke,  the  Standard- 
mammoth  mine  at  Mace,  and  the  Last  Chance  mine  at  Wardner;" 
the  Bunker  Hill  and  Sullivan  Mining  and  Concentrating  Company, 
Dwnino-  the  Bunker  Hill  and  Sullivan  mine  at  Wardner;  Larson  and 
"These  different  mines  are  officially  designated  by  the  company  as  the  Burke  mines,  the 
tfaee  mines,  and  the  Wardner  mines.  It  is  less  confusing  to  the  reader,  however,  inas- 
much as  there  are  other  mines  at  Burke  and  Wardner  not  owned  by  this  company,  to 
detain  the  old  familiar  names  by  which  the  mines  are  still  known  to  all  in  the  district. 
