The Anaconda standard. [volume] (Anaconda, Mont.) 1889-1970, 1895-11-30
IMPROVED GOLD MINING.
Elements In Reducing tho Cost of work.
ing the Ore.

From the New York Post.
Recent reports of increasing produe-
ton of gold In this country and else
where have attracted attention to new
methods OF mining and treating the
ore. which have recently reduced the
cost of obtaining the metal. and made
possible the working of mines contain
ing very small percentage of gold.
In the Colorado gold district the best
results in this direction have not yet
been reached. 1t is predicted that
when the time comes for the enormous
deposit OF low grade ore proved to ex-
list at Cripple Creek to be treated any
where near as cheaply as the cost at
johannesburg, Cripple Creek will pro-
duce more gold than johannesburg,
where ores are treated by stamp mills,
the "tailings" being passed through
cyanide mills Ten years have been
spent in reaching the high state of
efficiency and economy there.
Rossiter Raymond. a mining en-
gineer who has had experience In the
Colorado mines, says:
The reduced cost of obtaining gold
from ores or rock containing 1t is due:
II. To the nuemous new deposits of
gold opened within the last few years.
Such deposits are, of course, more
cheaply mined while operations are
conducted near the surface. In this
country the increased activity in gold
mining is doubtless due largely to the
DISBURSEMENT Of silver mining by
the fall in the price of silver A large
army of prospectors, formerly seeking
for silver in preference to gold, is now
looking for gold. But the most inn
portant new Developments in gold are
those in South Africa, where the de-
posts Though they have been overes-
timated in the speculations of the Lon
don stock markeD are unquestionably
of immense value and productive ca
pacity.
"2. To the increased efficiency of
mining methods and machinery (high
explosives, power drills, improved
hoists and pumps, cable tramways,
etc., which permits large quantities of
low grade material TO be handled at
a profit
"s. To the cheapening of labor and
supplies by the extension Of railroads,
the increase of population. etc.
- To the multiplication Especially
In this country of smelling and other
reduction works, which can utilize 9TH
er ingredients in gold-bearing rock
dead or copper directly, and iron or
silica. as fiuxes), so as to be able to
pay to the miner, In some cases, the
full value of the gold.
'5. The only innovation in metallur-
gical methods for the extraction of
gold. apart from variations in smelt-
ing processes, is the so-called cyanide
process. which promises to treat cheap
ly certain classes of ores and 'tailings'
Its principal competitor is the chlorf-
nation process, which is very old, but
has been much improved and is now
the most perfect of all methods for
gold extraction from material suitable
to II. This process usually requires a
preliminary 'roasting;' and Ii is claim
ed that the cyanide process can be
successfully operated without the pre-
liminary. Probably the ultimate YER
dict of practice will be that each pro-
cess has it's special field and that the
choice between them will depend upon
careful consideration of the elements
of the special case-nature of mate
rial, cost of plant, etc. At the most
successful of the southern gold mines,
the Halle mine. in South Carolina, a
profit is secured from material contain
ing as mined about 81 per ton This
is first crushed and amalgamated in a
stamp mill. and then the sulphide ores,
unaffected by amalgamation, are saved
by mechanical concentration, to be
roasted. chlorinated and leached.
Rock yielding free gold to the ex-
tent of 50 per ton can be mined and
amalgamated with profit under favor
able conditions as to size and accessi-
bility of deposit, cost of power, wages,
etc. provided the operation is on a
large SCALE"