Custer weekly chronicle. [volume] (Custer City, S.D.) 1890-1931, 1908-01-04
HoMESTAkE SLIME PLANT.
39,46S Tons Treated During the Month
OF November Extracting 90 Per
Cent of the Gold.

At this time of the year as the new
year with all its bright possibilities is a
hand, and we are preparing to say fare
we'll to the departing year, it loes wei
to cast about and see the progress tina
has been made during the past in min
! ing and thus get an idea of what the
future has in store for us in the mining
world. One of Deadwood mcst recent
and unique plants in the mining indus
try, the Homestake shines plant, locat
ed in the city, is something to be proud
of. 1t treats very low grade of ore al
nominal cost and is paying the com.
pany we'll
Now that the Homestake mine il
again producing it's normal mix of ore
after the difficulties caused by the frtl
the slime plant Of this company has
reached point where the showing will
approach the work OF the future, and
Superintendent c. w. Merrill, designer
Of the plant and inventor OF the special
process that makes it entirely unique in
the mining world, has made public fig
ures relating to the cost and operation
that will make interesting reading.
These figures are based on actual opera
ton of the plant for the month of No
vember, during which 81 presses were
completed and running. Today 22 of
the "A filter presses are in operation and
with the addition Of the two others, a
still further change will be made in the
cost of recovery figures.
During the month Of November the
plant treated 9,46S tons of slime for a
recovery Of IS per cent by charge and
residue assays and 81 per cent by bul.
lion while the total costs were approx.
mately 81 cents per ton. The average
value of the shines treated was 80 cents
per ton. The cyanide decomposition
was 037 of a pound for the first ten
days, O.35 tor the second ten and 0325
for the last ten days. The zinc con-
sumption was o. of "a pound of zinc dust
per ton Of lime while the lime consump.
tion was Al pounds per ton. During the
last ten days of the month which may
be taken as fair sample of the work
being accomplished at present in the
big plant, an average Of ,435 tons of
slime we're treated per day for recov-
cry of 80 per cent The full capacity of
the plant Is placed at ! 500 tons every "A
hours on the shines from the ore mix
now being nlilled.
One of the most interesting features
OF the work is the low consumption of
power This was less than one-twen.
tieth of hilowalt per ton Of slime per
day, and according 10 AIR. Merrill this
would be reduced to a merely nominal
figure were it not for the necessity OF
compressing "A large volume of air III or.
der to oxidize the reducing chemicals
calls for at least seventy per cent of the
power used in the treatment of the
shines.
The explanation of the small amount
of power used is the fact that there is
no agitation Of pulp and TO the further
possibility of using very small bulk OF
solution, namely, one to one or less be-
ing all that is leached through the slime
cakes.
The extraction of the values from the
shines ranges from So to 81 cents, at a
cost of 80 cents per ton treated. The
saving of value is conforming strictly to
the extraction secured by experiments
and the cost at the present time is five
cents per ton more than that predicted
The slime plant has had thorough
testing with different character ores
During the period of the memorable fire
last summer, or rather during that per
iod when the mills were able to resume
crushing after a months idleness, ths
Homestake was obliged to secure its ore
from the open cut, surface rock being
used. While this ore was of lower
grade and slower of treatment than tha
taken from the lower levels as today i
yielded slightly higher recovery (uE
to 50 per cent? AS was to be expected
from ore containing practically no sui
phides.
The slime plant is today approachin!
its.normal working basis. most of th'
construction work having been complet
ed and the force of workmen being grad
ually reduced to an operative basis. Tn
automatic sluicing device, whicn is on
of the important features of the plant
mas proven entirely satisfactory in thi
the largest slime plant in the world
The presses hold 26 tons each while tn
largest hand removal press operate
elsewhere have d capacity ofbut six ton
each.
Mr.. Merrill figures that the recover
will shortly be brought up To 80 per cen
or slightly better and the cost reduce
materially, just as the costs per ton {
the cyanide sand plants have been rs
duced until today they are lesss tina
rs cents per ton of material treated, a
compared with nearly double that Fl.
ure during the early operations Of thes
plants.
The addition of this plant has brougt
the recovery from Homestake ore to s
per cent at total milling cost for crusl
ing, amalgamatine and cyaniding of al
proximately 80 cents per ton.-Dea'
wood Telegram.
st. Louis reports falling off of 600 s.
looms in the course Of year, whic
only shows how quick st. Louis s.
loon keeper can make enough to reiil
on.
The annual meeting of the South d,
kota Bar association will be held at WI