The Goldfield news. [volume] (Goldfield, Nev.) 1904-1911, 1905-12-01
TONOPAH MINING CO.'S MILL
s. A. Worcester Gives a Minute Description of 1t In
Mining Journal.

In the last issue of the Mining and
Engineering Journal, 8. A. Worcester
describes the new mill to be built for
the Tonopah Mining company, as fol-
lows:
The Tonopah Mining company's
mill is to be located at Goldfeld juno
ton, about Is miles from the mines.
The ore will be delivered to the bin ut
the crushing and sampling plant IN
trains of standard-gauge dump cars,
the railroaad being owned by the
Tonopah Mining company (Which is
also erecting a large electric power
plant for furnishing current to mines
and mills).
Ore from the IN gate falls to the
No. 7A crusher; and, when crushed, it
is elevated to the revolving screen
with 1A-inch perforations. All over
size divides in two spouts to the No.
A crushers, which deliver to the same
elevator as the No. ~ crusher. When
the material passes the 1A-inch perfo.-
%ations, it is sampled by the first Vein
sampler, the rejection passing to the
mill conveyor, and the sample (about
1-7) passing to the rolls, which reduce
it to about u inch. This n inch prod
uct passes to the second Vein sampler,
which takes a IT sample and sends its
rejection also to the mill conveyor
(about $50 feet long,, which delivers
the ore ON the longitudinal conveyor
operating over the bins of the 100
stamp mill.
A self-propelling travelling tripper
delivers the ore to any bin desire l.
Bin gates and Challenge feeders de-
liver the ore to 10-stamp batteries of
1050-pound stamps, with apron-froar
mortars having cast iron bases and
concrete foundations. The batteries
are provided with the simple back
knee frame, and are driven in two
sections of so stamps each by $50
horse power induction motors located
on the main floor. A swinging belt
tightener is used for each 10-stamp
battery, and the motor belts, driven
with the slack side on top, are tight
ened by moving the motor on it's base.
This stamp mill drive is simple and
efficient. Self-oiling bearings are usrd
throughout the plant.
The pulp from the stamps (Which
drop 100 times per minute and crush
in cyanide solution) passes to 10 coarse
classifiers in which the coarser product
is re-ground in five 5-foot Huntington
mills, to 5000 mesh. This pulp then
joins the fines from the classifiers and
is elevated by the 6o-foot sand wheel
to the twenty-five classifers arranged
upper 10 are re-classifed in the lower
ones, and the slime from all goes to the
9 slime watts with agitators, while the
sand from the lower cones passes to
one or other of the two sand collecting
tanks (33 by 8 feet), to which they are
delivered by the Buffers revolving dis
tributor. Each of these collecting
tanks has three slime gates; when
filing the tank, the water and slime
pass over to a 54-inch Premier sand
pump, and are raised to a fine class
iier. This sends its slime to the ap-
propriate tanks and returns any fils
sand to the collecting tank.
After draining in the collecting
tank, the sand is excavated by an auto
matte machine and delivered to the
central belt conveyor; this in turn de-
livers to a centrifugal distributo Or
placed over any desired teaching tank.
Both excavator and distributor travel
on rails the whole length of the two