THE  ANNIE  LAURIE  MINE,  PIUTE  COUNTY,  UTAH. 
By  Waldemar  Lindgren. 
Location. — The  principal  part  of  the  gold  and  silver  mined  in  Utah  is  derived  from  a  few 
camps  to  the  east  and  south  of  Salt  Lake,  such  as  Park  City,  Bingham,  Mercur,  and  Tintic. 
A  broad  strip  comprising  nearly  half  of  the  State  and  including  almost  all  of  the  eastern 
counties  belongs  to  the  Plateau  Province  and  contains  few  if  any  deposits  of  precious  metals. 
This  is  true  also  of  the  southern-central  counties,  which  likewise  form  a  part  of  the  Plateau 
Province.  The  western  tier  of  counties,  adjoining  Nevada,  contains  among  its  many  desert 
ranges  scattered  deposits  of  gold  and  silver,  but  few  of  them  have  attained  any  noteworthy 
production. 
About  the  year  1900  statements  began  to  appear  in  the  press  concerning  a  new  gold  dis- 
covery of  importance  in  the  southern-central  portion  of  the  State,  in  Piute  County.  This 
deposit,  which  is  known  as  the  Annie  Laurie  mine,  has  amply  verified  the  predictions 
regarding  its  value,  inasmuch  as  its  production  during  the  last  few  years  amounts  to  over 
$2,000,000. 
The  Annie  Laurie  mine  is  situated  175  miles  south  of  Salt  Lake  City,  on  the  west  side  of 
Sevier  Valley,  in  Piute  County,  just  over  the  line  from  Sevier  County.  The  region  was 
known  to  be  mineral  bearing  from  the  earlier  days,  for  the  deposits  of  Marysvale  and  Bullion 
Creek  are  located  in  the  same  vicinity,  a  few  miles  to  the  southeast;  but  in  the  new  district, 
which  is  named  the  Gold  Mountain,  no  productive  mines  had  previously  been  developed. 
The  district  was  discovered  about  fifteen  years  ago,  but  as  the  ores  did  not  prove  amenable 
to  the  ordinary  amalgamation  process,  the  primitive  reduction  works  erected  were  a  com- 
plete failure.  With  the  advent  of  the  cyanide  process  a  method  was  found  which  permitted 
the  successful  working  of  the  ores,  and  the  present  mill  was  built  at  the  mine  by  the  Annie 
Laurie  Mining  Company  in  the  year  1899.  The  production  of  gold  and  silver  of  the  mine 
since  that  time  has  amounted  to  $2,100,000,  or  about  $400,000  a  year. 
Development. — The  deposit,  which  is  to  be  classed  with  the  fissure  veins,  is  located  at  an 
elevation  of  about  9,600  feet  on  the  northerly  slopes  of  that  cluster  of  high  peaks  which 
culminate  with  elevations  of  over  12,000  feet  in  the  Belknap  and  Delano  mountains.  The 
development,  which  extends  over  a  horizontal  distance  of  2,400  feet,  is  effected  by  four 
principal  tunnels,  the  upper  one  called  the  Blue  Bird  and  the  lower  three  referred  to  as  No.  3, 
No.  4,  and  No.  5.  The  vertical  distance  between  the  Blue  Bird  and  No.  5  tunnel  is  800  feet. 
All  of  the  tunnels  are  crosscuts,  and  the  lowest  one  penetrates  the  barren  rock  for  over  3,000 
feet  until  it  strikes  the  vein.  In  all,  the  tunnels  and  crosscuts  aggregate  several  miles  in 
length. 
The  reduction  of  the  ore  is  carried  on  by  means  of  a  dry-crushing  process,  followed  by 
cyanide  percolation  and  amalgamation.  The  mill,  which  has  a  capacity  of  200  tons  and 
which  is  expected  to  be  enlarged  to  300  tons,  crushes  the  quartz  by  four  sets  of  rolls  to  a 
40-mesh  screen.  The  percolation  takes  place  in  the  usual  large  tanks  and  occupies  a  period 
of  eight  days.  The  amount  of  sulphides  in  the  ore  is  exceedingly  small,  so  that  concentra- 
tion on  tables  is  deemed  unnecessary.  From  the  cyanide  vats  the  pulp  goes  (<»  (lie  amal- 
gamating tables,  where  the  coarser  gold  which  may  have  remained  unattacked  by  the 
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