boutweli,.]  PARK    CITY    MINING    DISTRICT,    UTAH.  147 
exploitation,  recent  progress  in  the  mining-  industry,  and  recent 
production. 
Development. — The  opinion  is  current  among  miners  that  the  ore 
bodies  of  this  district  lie  deep  and  do  not  crop.  The  means  and 
determination  to  explore  widely  and  at  depth  have  resulted  in  very 
extensive  development.  Twent3r-two  shafts,  now  accessible,  have 
reached  a  depth  of  at  least  500  feet,  10  a  depth  of  at  least  1,000  feet, 
6  a  depth  of  1,300  feet,  and  1  a  depth  of  2,000  feet.  Lateral  develop- 
ment has  been  proportionate^  extensive.  According  in  position  with 
that  of  the  great  fissure  zone,  and  of  the  ore-bearing  limestone  forma- 
tions, the  underground  workings  of  the  main  properties  lie  in  two 
parallel  northeast-southwest  belts.  In  addition  to  the  shafts  on  indi- 
vidual properties  the  northern  belt  is  entered  by  two  long  tunnels, 
the  Hanauer  and  the  Alliance;  and  the  southern  by  three,  the  Ontario 
drain,  the  main  Ontario-Daly-Daly  West  work,  and  the  Daly-Judge 
drain  tunnels.  The  adjoining  mines  in  each  belt  have  been  connected, 
so  that  it  is  possible  to  pass  continuously  underground  from  one  end 
of  each  belt  to  its  opposite  end.  Thus  in  the  southeast  belt  there  is 
continuous  underground  connection  in  a  northeast-southwest  direction 
for  a  distance  of  over  5  miles.  Furthermore,  a  crosscut  only  450  feet 
in  length  would  connect  these  two  belts  and  afford  continuous  under- 
ground connection  between  all  the  great  mines  of  the  district. 
Character  of  ores. — The  ores  mined  in  this  district  are  essentially 
argentiferous  lead  ores  with  accessory  gold  and  copper  and  a  siliceous 
gangue.  The  values  in  the  sulphide  ore  lie  in  galena  (lead  sulphide), 
tetrahedrite  (gray  copper),  and  pyrite  (iron  sulphide);  and  in  the  oxi- 
dized ore  in  cerussite  (lead  carbonate),  angelsite  (lead  sulphate),  azurite 
(blue  copper  carbonate),  malachite  (green  copper  carbonate),  and  com- 
plex oxidation  products.  Silver  is  obtained  from  the  iron,  lead,  and 
zinc  approximately  as  follows:  3  ounces  to  each  per  cent  of  iron,  1 
ounce  to  each  per  cent  of  lead,  and  five-tenths  of  an  ounce  to  each  per 
cent  of  zinc.  a  Silver  has  also  been  found  in  its  native  state.  Zinc  is 
a  common  associate  in  fissure  ore,  and  appears  to  increase  in  depth 
and  toward  the  great  intrusive  mass  at  the  southwest.  Barite  and 
fluorite  occur  sparingly.  Oxidized  ores  are  still  mined  to  a  limited 
extent,  but  the  bulk  of  the  shipments  of  both  crude  ore  and  concen- 
trates is  composed  of  sulphides. 
Although  values  as  a  whole  run  rather  high,  a  noticeable  difference 
in  value  exists  between  ores  from  different  parts  of  the  district. 
An  average  high-grade  ore  carries  about  60  ounces  silver,  40  per  cent 
lead,  0.25  ounce  gold,  and  2.5  per  cent  copper.  Ordinary  crude  ore 
carries  50  to  55  ounces  silver,  20  per  cent  lead,  0.04  to  0.05  ounce 
gold,  1.5  per  cent  copper,  and  10  to  18  per  cent  zinc.     Just  as  the 
"This  statement  is  based  upon  results  secured  from  a  large  number  of  precise  tests  by  Mr.  F.  W. 
Sherman,  superintendent  of  the  Daly  West  and  Daly-Judge  mills. 
