Elk City mining news. (Elk City, Idaho) 1903-1913, 1904-12-03

Cne cyanide process. AL Ine f1OneSIedh
no concentration is practiced, but the
shines and sands are leached by cyanide
solution separately.
All of the shistose ores occur in the
Archaan, which forms the basement
series of rocks Of the Black Hills region.
On the upturned edges of this Archaan
terrane rest the sedimentary beds rep
resenting every important large division
known to geological science, from Sill
urian to Tertiary. In the Cambrian and
Carboniferous beds, and in part also
possibly the Devonian, occur the So
called silieious ores, though these are
rarely no more silicious than the pure
quartz ores of the Arch@an. The pres
ence of these ores in the sedimentary
beds near Galena, Bald Mountain, Green
Mountain and Terry's peak was recog-
nized early in the history of mining in
the Hills, and large number of claims
were then located on these beds, partic-
ularly in the districts named. A few
hundred tons of ore were shipped out of
the Hills from Galena, rich in silver,
lead and gold, and later several hundred
tons from the other districts were ship
ped to Omaha, Denver and other smell
tiers. For. years repeated efforts were
made to treat these ores at the mines,
but without success. Up to 1886 it was
not determined positively that the gold
was associated with tellurium ia these
ores. The pioneers in the school of ex-
perimental metallurgy were the Port
land Mining company, near Portland;
the Welcome Mining company, at the
eastern base of Terry's peak, near Ter
ry, and the Sitting Bull company, near
Galena. The latter company was really
an exception, as their ore was either
lead-silver ore, which was smelted at
the mine, or silicious chloride silver
ore, which was milled latter roasting
in various types af rotary furnaces) by
amalgamation in pans with salt, blue
stone, ETC.. The Portland, Welcome
and Snowstorm companies expended
large sums in building mills and trying
various methods of treatments, but
without success, viewed either. chem
ically, mechanically or commercially.
The next company to take up the still
unsolved problem was the Buxton, near
Terry. Here the first steps toward the
real solution of the problem was taken.
Leaching by means of bromine solutions
was the process tried, but, although it
gave results superior to any other that
had been attempted, it was not a fnan-
cial success, and was eventually aban-
doned. All of. these expensive opera
lions were carried on in a new country,
from 200 to 300 miles distant from the
railroads.
In July, 1886, the first railroad reach
ed Rapid City, at the eastern gateway
of the Hills, and within four years fol-
lowing that date the barrel chlorination
process was in operation and doing
much to simplify the vexed problem of
the metalluragy of these ores, In 1892
the cyanide process was introduced in
the treatment of these same ores, and
was found to yield as satisfactory re-
suit as, if not better than, the chlorina-
ton process. Many experiments. were
made and for that matter are still be-
ing made-in the treatment of these
ores by wet process.
The Imperial company's mill and that
of the Golden reward company are the
only ones where the ore is crushed dry,
The solutions being subsequently in
troduced. In the Dakota mill the ore
is crushed in the solution, the battery
water containing o. percent. of potas-
SUM cyanide, and four pounds of lime