116  CONTKIBUTIONS    TO    ECONOMIC    GEOLOGY,  1905. 
occurs  in  shoots  and  consists  of  chalcopyrite  intimately  intergrown  with  quartz.  Concen- 
tration is  not  effective  owing  to  the  fineness  of  the  particles  of  chalcopyrite  and  the  practical 
impossibility  of  a  clean  separation.  The  ore  is  highly  siliceous  and  carries  a  low  precious- 
metal  content .  One  workable  ore  shoot  has  been  developed  in  the  Union  Copper  Company's 
workings,  and  this  is  open  to  a  depth  of  800  feet.  The  ore  is  shipped  to  New  York,  and 
to  Ducktown,  Tenn. 
Besides  the  two  districts  mentioned  North  Carolina  has  many  copper-bearing  veins  in  the 
gold  belt  lying  along  the  boundary  between  the  old  Algonkian  ( ?)  slates  and  the  granite  mass. 
The  Crosby  and  Concord  Hill  mines,  near  Concord,  arc  among  the  best  known,  the  ore  being 
chalcopyrite  associated  with  siderite  (carbonate  of  iron). 
In  the  mountain  region  of  Jackson  County  there  are  several  copper  veins,  formerly  worked, 
that  carry  copper  pyrite.  They  are  in  metamorphic  schists  but  usually  occur  associated 
with  aiiiphibolite  bands.  The  only  property  recently  worked  is  the  Cullowee  (Davies  post- 
office),  near  Sylva,  on  the  Murphy  branch  of  the  Southern  Railway.  The  ores  consist  of 
chalcopyrite  in  a  quartz  gangue,  occurring  in  a  band  of  amphibolite.  The  development 
work  on  the  various  properties  is  not  sufficient  to  warrant  an  estimate  of  the  importance  of 
the  veins  as  future  producers.  The  ore  shoots  so  far  known  are  not  large,  and  though  the 
veins  arc  often  traceable  by  their  iron-stained  outcrop  for  a  mile  or  two,  development  work 
is  limited  to  a  few  points.  These  properties  are  at  present  several  miles  from  the  railways, 
but  branch  lines  could  be  easily  and  cheaply  constructed  and  would  serve  the  timber  and 
clay  industries  as  well. 
The  Rowan  and  Salisbury  copper  mines  have  been  worked  to  some  extent  and  the  Mead 
mine  has  been  developed. 
NEVADA. 
Nevada  has  as  yet  only  a  small  annual  production  of  copper.  Six  counties  yielded  a  total 
of  29,317  pounds  of  copper  in  1904,  the  largest  production,  13,963  pounds,  coming  from 
Eureka  County. 
Elko  County  produced  7,200  pounds  in  1904,  from  the  high-grade  gold-bearing  ores  of  the 
Weston  and  Frank  mines,  in  the  Railroad  district. 
Esmeralda  County  gave  the  small  amount  of  300  pounds  in  1904.  The  Sodaville  copper 
belt  occurs  in  this  county,  at  the  north  end  of  the  Pilot  Mountains,  about  18  miles  east  of 
Mina,  a  new  town  on  the  Carson  and  Colorado  Railway.  The  copper  ores  occur  in  a  contact 
zone  12  miles  long,  on  the  borders  of  a  granite  intrusion.  On  the  east  side  of  the  range  the 
Dunlap  property  is  being  developed  by  the  Guggenheim  interests.  At  the  north  end  the 
copper-contact  mine  is  shipping  small  amounts  of  ore,  and  at  the  south  end  the  D'Arcy  mine 
is  also  producing.  On  the  west  side  of  the  mountains  the  Utavarda  Copper  Company,  at 
Garnet,  shows  a  vein  said  to  be  13  feet  wide,  opened  by  a  70-foot  shaft  and  proved  for  2,700 
feet  horizontally. 
Eureka  County  yielded  13,963  pounds,  of  a  value  of  $1,380,  mostly  from  the  Tenabo 
Mining  and  Milling  Company's  mine  in  the  Cortez  district. 
Lander  County  yielded  3,200  pounds  of  copper  in  1904. 
Nye  County  produced  but  70  pounds  of  copper,  from  the  gold-silver  ores  shipped  to 
smelters.  , 
White  Pine  County,  whose  great  ore  bodies  are  now  being  so  actively  and  extensively 
developed,  yielded  but  4,584  pounds  of  copper  in  1904.  Within  the  last  few  years  a  great 
mining  district  has  been  quietly  developed  in  this  county,  and  its  mines  will  soon  take  high 
rank  among  the  world's  great  producers.  The  region,  commonly  known  as  the  "  Ely  dis- 
trict," lies  6  miles  west  of  Ely,  the  county  seat,  which  is  140  miles  distant  from  Toano,  a 
station  on  the  Southern  Pacific  Railroad.  The  place  is  officially  known  as  the  "  Robinson 
mining  district." 
The  mineral-bearing  area  consists  of  shales  and  limestones,  intruded  by  an  immense  dike- 
like mass  of  monzonite-porphyry  that  is  traceable  for  some  miles  in  length,  with  a  later 
intrusion  of  rhyolite-porphyry  transversely  cutting  across  the  porphyry  in  the  center.     On 
