weed.]  COPPER    DEPOSITS    OF    EASTERN    UNITED    STATES.  219 
as  the  Weverton  sandstone,  whose  finer  beds  contain  fossils  of  Cam- 
brian age,  overlies  and  flanks  this  Catoctin  schist,  and  the  copper 
solutions  from  the  trap  rock  have  in  part  penetrated  the  sandstone 
for  a  few  feet  and  deposited  ores  in  small  amounts  on  joints  and 
fractures.  Tbe  ore  found  in  this  section  is  commonly  the  red  oxide 
of  copper,  with  some  native  copper,  and  the  green  carbonate  (mala- 
chite). These  minerals  occur  usually  associated  with  quartz,  calc- 
spar,  and  epidote.  In  the  Manassas  Gap  properties  grains  and  films 
of  copper  pyrite  and  of  peacock  copper,  or  bornite,  also  occur. 
In  southern  Virginia,  in  Carroll,  Grayson,  and  Floyd  counties, 
there  are  a  number  of  copper  properties  which  were  formerly  rather 
prominent  producers;  in  fact,  the  mineralization  of  this  section 
has  been  well  known  ever  since  Revolutionary  times.  The  famous 
Bertha  zinc  mine  and  the  Wythe  lead  mine  are  situated  in  this  sec- 
tion. Near  these  mines  there  is  an  opening  known  as  the  Iron 
Ridge  mine,  which  is  on  the  south  end  of  the  great  gossan  lead  of 
Virginia,  a  vein  or  series  of  veins  whose  outcrop  of  brown  hematite 
ore  can  be  traced  for  10  miles  or  more  to  the  northeast.  This  hema- 
tite ore  has  been  very  extensively  worked  and  the  capping  removed 
down  to  the  unaltered  sulphide  ores  which  underlie  the  limonite. 
The  unaltered  ore  is  from  a  few  feet  to  50  or  more  feet  in  thickness. 
It  consists  of  magnetic  pyrite  or  pyrrhotite,  with  scattered  specks 
of  copper  pyrite.  Occasionally  bunches  and  layers  of  rich  copper 
ore  have  been  found,  but  the  main  body  of  the  deposit  contains, 
I  am  told  by  one  of  the  largest  shippers  from  this  region,  not  over 
three-fourths  of  1  per  cent  of  copper.  Owing  to  the  predominance 
of  the  magnetic  sulphide,  which  is  low  in  sulphur,  this  ore  has  not 
been  valuable  for  acid  making,  and  hence  has  remained  undeveloped. 
If  the  reported  success  in  utilizing  the  sulphur  from  similar  ores 
at  Ducktown,  Tenn.,  proves  to  be  true,  the  ores  of  this  great  ledge 
may  some  day  prove  workable.  At  the  present  time  no  development 
work  is  being  prosecuted  on  this  lead. 
At  a  place  north  of  Hillsville,  the  county  seat  of  Carroll  County, 
the  New  York  and  Virginia  Copper  Company  has  opened  up  a  vein  of 
dark-greenish  colored  amphibolite-schist  containing  smooth,  rounded 
masses  of  copper  pyrite,  some  of  them  as  large  as  a  hickory  nut.  These 
concretions  show  slickensides  and  movement,  and  occur  in  a  sheared 
zone  about  8  feet  wide.  The  amount  of  copper  is,  however,  too  small 
to  pay  for  working,  and  the  gangue  is  unfavorable  either  for  cheap 
concentration  or  for  smelting.  The  dump  heap  shows  a  few  hundred 
tons  of  this  low-grade  ore.  At  the  present  time  the  property  has  been 
dismantled  and  the  machinery  shipped  to  the  Toncray  mine,  about 
12  miles  east  of  Christiansburg,  a  property  which  is  regarded  by 
local  residents  as  the  best  in  this  part  of  Virginia. 
