SOUTHWESTERN    NEVADA    AND    EASTERN    CALIFORNIA.  69 
hematite  and  limonite.  Vugs  elongated  parallel  to  the  direction  of  the  veins  arc  sonic- 
times  seen.  On  encountering  the  first  veins,  in  the  one  instance  noted,  these  veins  are 
deflected  downward. 
The  veins  of  the  third  class  are  of  later  origin  than  those  of  the  second,  and  cut  them.  As 
a  iple  they  are  more  narrow  and  less  continuous  and  dip  more  steeply  than  the  veins  of 
the  second  class.  The  veins  of  this  group  often  curve  sharply,  and  the  quartz  in  I  hem  is 
similar  to  that  in  the  second  group. 
In  the  vicinity  of  the  vein  the  granite  is  cut  by  joints  stained  by  limonite  and  manga- 
nese dioxide,  which  are  parallel  to  or  join  the  quartz  veins  at  low  angles,  and  the  surround- 
ing partially  decomposed  granite  is  said  to  carry  values.  The  granite  near  the  veins  is 
sometimes  thickly  peppered  with  cubes  of  pyrite  altered  to  limonite. 
The  ore  of  the  two  younger  sets  of  veins  so  far  encountered  is  practically  all  oxidized, 
although  a  little  original  galena  remains.  The  predominant  original  sulphide  was  pyrite, 
and  limonite  cubes  after  pyrite  are  common  in  the  quartz.  Assays  show  the  values  to  be 
in  the  proportion  of  1  of  gold  to  4  of  silver.  Some  silver  chloride  was  noted,  while  secondary 
native  silver  is  reported.     In  one  prospect  calcite  was  noted  as  a  gangue,  with  quartz. 
While  the  quartz  of  one  set  of  veins  is  of  pegmatitic  origin,  its  mineralization  is  prob- 
ably later  and  genetically  connected  with  the  filling  of  the  fissures  of  the  second  or  possibly 
the  third  system.  After  the  veins  of  the  second  system  were  fractured  a  second  period  of 
mineralization  followed,  perhaps  in  Tertiary  time.  Later  the  veins  were  crushed  and  sur- 
face waters  have  more  or  less  completely  oxidized  the  sulphides. 
Wood  and  water  are  hauled  from  Antelope  Springs,  some  9  miles  away.  Trappmans 
Camp  is  40  miles  by  road  from  Goldfield. 
Wilsons  Camp. — Wilsons  Camp,  situated  on  the  north  slope  of  O'Donnell  Mountain, 
is  2  miles  north  of  Trappmans  Camp,  and  was  discovered  in  May,  1904.  Five  miners 
were  employed  in  July,  1905.  At  that  time  several  shallow  shafts  and  short  tunnels 
were  open. 
The  predominant  country  rocks  are  a  white  altered  rhyolite  and  a  biotite-andesite. 
Both  rocks  are  cut  by  rather  steeply  dipping  quartz  veins,  the  majority  of  which  strike 
northeast,  although  some  strike  east.  The  quartz  veins,  often  crustilied,  are  character- 
ized by  quartz-lined  vugs.  Since  its  formation  the  quartz  has,  in  instances,  been  crushed. 
Limonite  and  less  commonly  malachite  stains  were  observed  on  the  quartz. 
The  reported  assay  values  run  from  $110  to  $180  per  ton,  and  the  average  proportion,  is 
1  of  gold  to  5  or  6  of  silver.  These  quartz  veins  are  to  be  con-elated  with  the  veins  of 
Silver  Bow. 
The  economic  conditions  at  Wilsons  Camp  are  similar  to  those  at  Trappmans. 
Gold  Crater. — The  mining  camp  of  Gold  Crater  is  situated  10  miles  east  of  the  summit  of 
Stonewall  Mountains.  Gold  Crater  is  an  inlier  of  older  rocks,  which  protude  in  rounded 
hills  above  the  basalt  flow  of  the  Ralston  Mesa.  These  older  rocks  are  much  altered, 
but  appear  to  be  predominantly  flows  of  andesite  with,  perhaps,  more  acid  varieties. 
The  first  locations  were  made  in  May,  1904.  In  the  fall  of  1904  several  hundred  people 
rushed  to  the  camp,  but  few  remained  long.  At  the  time  of  visit  (July  7,  1905),  a  number 
of  lessees  were  at  work. 
The  rocks  have  been  in  some  cases  strongly  silicified,  in  others  changed  to  a  chalky 
mass  through  kaolinization.  In  the  silicified  facies  the  feldspar  phenocrysts  have  often 
been  entirely  removed,  while  the  biotite  has  been  altered  to  a  silvery  micaceous  mineral. 
The  silicified  eruptives  weather  into  rugged  crags  and  wall-like  exposures.  The  country 
rock  has  been  fractured,  often  brecciated,  and  in  instances  faulted.  It  is  often  intensely 
stained  by  limonite  and  hematite,  especially  along  fractures,  and  from  such  places  rich 
gold  pannings  are  obtained.  The  ore  is  said  to  run  from  $40  to  $240  per  ton.  A  little 
chrysocolla  was  observed  along  some  joints. 
Waters  carrying  silica  and  metallic  salts  in  solution  appear  to  have  ascended  along  faults, 
brecciated  zones,  and  joints  in  the  country  rock,  and  there  to  have  deposited  silica,  pyrite, 
and  some  copper  sulphide.     Later  surface  waters  oxidized  the  sulphides  and  set  the  gold 
