The DeLamar nugget. [volume] (DeLamar, Idaho) 1891-1900, 1898-03-04
DeLamdT Cyanide Plant.
The FiItcring Press at work.
-Four tee NOR. Lceciiing Tanks to be Put
In without Delay.

successful operation. As this press j
!, a recent introduction to the cyanid
process. description of it and of the
process in use here may be of interes
to our readers. To begin with, briefly
the cyanide process is a methnd of dis
solving the gold and silver contained
in the orc with solution of cyanide o.
potassium and leeching out the solu
ton and precipitating the values there
from. The process is apparently sim
and the solution filtered thorough il
+ until it has carried with it practically
all the values it contained. Then, by
the process most in vogue, known as
the Macarthur Forest process, which is
controlled by patents, the solution is
filtered through zinc shavings, and the
gold and silver having greater affin-
ity for the zinc, is caught from the so.
luton and recovered. This method
of treating ores has been in use for
several years and with many classes of
ores has been cheaper and successful
in saving higher per centage ofvalues
than the former milling processes en-
ployed. But only small proportion
of the mines have ores which can be
completely dissolved by cyanide and
there are SO many conditions to be con-
sidered that mine owners should not
undertake to adopt its use without
thorough investigation by competent
metalurgist and chemist. Even as re-
Gently as two years ago it would not
have been practicable to have treated
DeLamar ores by this process, as de-
veloped up to that time. Captain
Plummer, then manager, after exhaus
tive tests and experiments made by
noted experts, had to abandon the
idea of lopting it. The famous Mer-
Gu. mi4es in Utah expended large sums
and ran greatly behind in trying to en-
play the process before fortunate
discovery made by one of the owners
who was not metalurgist or expert,
led to the phenomenal success the COM
pany is now achieving. That discovery
made the process practicable here. 1t
was imply having learned that-it was
not necessary to crush the ores so fine
before leeching that the pulp would
slime so that it could not be success
fully leeched. By filling leeching vat
with ore crushed to the size of marbles, |
it was found to leech properly and that
the solution practically carried with it |
all the bullion. On the other hand, it |
was found that at the great DeLamar,
Nevada, mines, where the ore is |
very hard, hinty quartz, the best re-
suits were obtained by grinding as fine
as 60 mesh.
At the mill here the ore, much of it
comes out of the mine quite fine, is run
over grizzly and the coarse rock run
through closely set rock breaker, and
goes from the ore bin direct to the
vats.
But, enough for the introduction, we
started to give a description of the
plant and process as employed here.
Beginning from the upper part of the
mill, the plant consists of two solution
tanks, the hydraulic press, several
tanks for the storage of solution, then
the leeching tanks and below them ali
1 tank into which the solution runs
after leeching through the ore, a force
pump to force the solution back,
~ orrraI xtrith fha | ,
20 the first tanks mentioned. An
iir compressor, with pipes running to
,he bottom of these two tanks, keeps
he solution constantly agitated and as |
hey are being filled, finely powdered
jnc is thrown into them which catches =,
he values in the solution. When one
ank is full and while the other is filling
he full tank is pumped through the
liter press, where the zinc powder !,
Iolding the gold and silver is filtered )
ut and held while the solution run. a
ling off is tested and cyanide added to G
ring it up to its proper strength again !
nd run into the storage tanks, from v
Whence it is drawn as required into the
eeching tanks, to go the same round n
nee more. (
At present there are ten leeching t.
anks employed, each holding little "
nore than thirty tons, and two of them I
re emptied and discharged every day. c
he leeching process thereby being car G
led on for four days on all of the ore, d