Elk City mining news. (Elk City, Idaho) 1903-1913, 1905-06-24

cal StlrrerS are USED III Cne Idllh, puI
in small mills wooden paddle will suf-
flee. Lead tanks are the best for con-
Quoting the acid treatment in, but as
they are very expensive and difficult to
transport, redwood tanks are generally
used in preference. They may be used
without protective coating, but it is
best to paint them with P. & B paint,
after which acid will have no effect on
them.
Below the acid tank there should be a
settling tank large enough to contain
all of the waste solutions from the re-
fining operations. After few days
the top solution is decanted off and run
through filter to insure against any
loss. To remove any excess of moisture
from the gold shines, either a filter
press or vacuum filter pan is necessary.
The former is to be preferred. Consid-
cradle hot water is necessary in the
room for washing out the acid and salts
from the precipitate. A convenient
way of obtaining it is to have a cold
water tank with a steam pipe leading
into it. By turning on the steam hot
water can be obtained in few minutes.
A good way to dry the precipitate is by
means of a steam coil arranged inside
of sheet iron box with shelves to sup
port the pans.
In designing the mill an important
point to consider is the economical fill
ing of the tanks with ore. If reservoir
tailings are being treated the plant
should be located below the supply.
Then they can be shoveled into cars
and dumped into the tanks from an
overhead track. If the plant must be
located above the reservoir, run the
cars up the incline by means of hoist
ing rope, and then run them to the
tanks by hand. If the tailings have to
be transported in wagons bridge with
a grating floor should be built over the
tanks, so that the wagons can drive on
to it and dump their loads directly into
the teaching tanks. If the tailings are
near at hand scrapers can be used in
stead of the wagons and the cost of
shoveling done away with. Small plants
can made use of scrapers to convey the
tailings to the side of the tanks and
then they can be shoveled in by hand.
In dry crushing mills the ore is al
ways elevated into bins and drawn off
into the tanks as desired. Some mills
use shaking spouts to convey the ore
from the bins, but the better way is to
use ore cars running on the track built
over the tanks. In handling dry crushed
ore there is always large amount OF
dust created, which represents a loss ii
it is allowed to get away. To prevent
this arrangements should be made fol
sprinkling the pulp at the earliest pos
sible stage with either water or diluted
cyanide solution. 1t should not contain
any more moisture than is necessary tt
allay the dust. In wet crushing mills
the handling of the pulp is complicated
because of the necessity of removing
the shines previous to cyaniding.
SLIME TREATMENT. The treatmen
of slime has always been the most ser
ious problem connected with the cyan
ide process. 1t has been solved in
great many instances, but such success
es have not resulted in the working on
| of a universal method of treatment, 70
the reason that shines vary in thei
physical properties.
Slime treatment may be divided int
: three distinct operations, but it will b
t necessary to consider only the first two
: l. Dissolving the gold.
2. Separation of the solution fror
the slime.
= 8. Precipitation Of the gold.
DIsSoLvING THE GOLD. This is a
S ways accomplished by agitating tn
slime in cyanide solution. The que!
: ton of the best form of agitation is a
e open one. Mechanical agitators of til
f paddle type are very good, but as the
: require considerable power to operat
: them, they are not much used. Gel
e trifugal pumps are used great de-
o and are satisfactory in every respe'
except that the cost of repairs is col
e siderable They are usually used
connection with conical bottom tanl
arranged 50 that the slime can be draw
y off from the bottom and thrown bac
d on top. Tie use of compressed air f,
e agitation is becoming quite common ar
- gives excellent results. The time r.
+ quired to agitate an ore is variable al
e must be determined by experiment.
e the time is short the agitation is conti