The Owyhee nugget. ([Silver City], Idaho) 1905-1984, 1906-04-20
THE NEW DELAMAR MILL
And Its Treatment of Shines by
Cyanide Process.

The DeLamar reconstructed cyanide
msll, started on trial run on the sec
ond day of this month, is now running
satisfactorily, and as it is the first re-
duction plant in the state using the
cyanide process, constructed with
special view of saving the values in the
shines, and new and novel in many of
its features, Nugget will attempt to de-
scribe it's construction and manner of
treatment of the ores, by following
them from the tramway at the top of
the midtown through the various op-
erations until the cyanide solution has
taken up the values in the ores, is
drawn into tank at the bottom Of the
mill and thence pumped to the precip,
itating tanks in the press room and
from hem forced through the filtering
presses aud the values recovered III the
shape of cyanides, ready TO 90 to
the refining room to have the zinc pow
ter cut out with acids and the result
ing product sent to the furnace to be
melted and cast into ingots ready for
market.
The ore coming down on tramcar
from the the mines is automatically
dumped into the hopper of scales,
where the weight of the carload is i'm
pressed in figures on a card. It IS then
dumped on to a grizzly, the finer por-
tion going by chute to a bin of rs
tons capacity, while the coarser rock
passing over the grizzly drops onto a
platform and is fed into rock crusher
whence it also falls into a bin. From
the bin the ore is let out Of gate onto
two union automatic feeders whence it
is fed into two sets of rolls, crushed
finer, drops into troughs and washed
into two six foot Chilian mills, where it
is ground in the solution until it pass
es out with the solution through 30
mesh screens.
AS the Chilian mills are new to the
majority of Nugget readers, brief de-
scription of these may be of interest
here. A heavy circular iron frame with
heavy base, set upon a solid cement
foundation, contains within it three
wheels with wide faces, each weighing
1000 pounds. These wheels revolve or
roll around track over the outer por-
tion of the base, driven by gearing in
the center of the frame connected to
the power shaft by pulleys and betting.
The ore, with the cyanide solution, is
fed into the mill from the top, falling
into the track of the wheels, and by
centrifugal motion thrown against the
screens set in the outer circle of the
iron frame, that fine enough to pass
through the screens falling into a
trough which carries it to the classifier,
the coarser falling back under the
wheels for further grinding. The weight
OF The three wheels and the gearing in
side of the frame of the mill is "a, 1000
pounds and the mill grinds rs to 100
tons of ore per day, the two in the De
Lunar plant however, being run at a
speed that their combined output is
only intended to be 12O tons each "a
hours.
From the mills, the shines and finely
ground sand are run with the solution
to Dorr classifiers, appliances employ
ed to separate the sand from the
shines. These are simply long, shallow
wooden boxes, not unlike an ordinary
bed for mixing mortar, with one end
of the box Set slightly higher than the
other. Inside is fixed a system of
shallow hoes or rakes which drop to
bottom of the box while heing drawn
toward the higher end and are lifted
above the contents while passing back.
As the heavy sand settles to the bot
tom it is constantly being raked over
the higher end of the box and convey.
ed by troughs to any desired one of six
iron teaching tanks, where it falls into
the tanks through pipe arranged dis
tributor, revolving On the same pres.
sure principle as an ordinary lawn
sprinkler, spreading the sand and so.
luton lightly and evenly over the sur,
face until the tank is full, when the
distributor is moved by trolley tC
another tank. In these tanks, the sand
is leached and the solution drawn of
and pumped to the precipitating tanks
gate in the tank opened and the sane
sluiced out into the creek.
The shines coming off the other end
of the classifier are run through pipe
to the bottom and small end of cone