Chicago eagle. [volume] (Chicago, Ill.) 1889-19??, 1893-05-20
MODERN GOLD MINING.
Sot So Romantic as the OId-Time Rocker.
but More Certain.

but More Certain.
The days OF ailuvial digging for
gold have gone, and now we have en-
tered upon the purely mechanical
eva of quartz-crushing. The days OF
individual effort have also gone. The
miner does not now prospect upon his
own account: he engages himself to
company. He does not make for
tune, but he averages a better in
come, says the Pail Mall Budget.
1t may interest some of our read
ers to learn how gold is obtained &C
cording to the modern system. The
first requisite is reef" 1t does
not pay to 60 deep down into the
bowels of the earth for quartz; but
when ridge of the mineral juts up
above the surface there is possib.-
ity of profit accruing to the miner.
Such ridge is, of course, the ''reef."
The quartz is quarried and broken
into pieces Of about the size of road
metal by means Of crushing machines.
1t is then ready for the stamp" 1t
is by no means rare for quartz to con-
tain gold; in fact it nearly always
does so. The rarity is to find quartz
which will repay the trouble of crush.
ing. The stamps are heavy cylp.
ders Of steel. Theyare usually lifted
up by water power, and allowed to
fall upon base block fitted into the
ground The prepared fragments OF
quartz rattle down a trough, along
which also flows stream of water,
until they are brought to rest under
the stamps" Beyond the stamps"
is very fine sieve 1t is clear that
the quartz can not be carried by the
water through the sieve until it has
been reduced to very fine powder
The process is very automatic. AS
the stamps go up and down the fine
particles pass on, while their larger
brethren are detained. From the
stamping process there is no escape
until the proper standard OF fineness
is reached.
So far the work is simple: it is in
separation OF the gold from the baser
minerals that the real difficulty lies.
Charged with fine powder the water
passes through the sieve, and flows
over a shallow bath of mercury.
Quicksilver is heavy, but gold is
heavier, and into the mercury
the larger particles of gold sink.
Then the water spreads itself out
over plates of copper. Upon the cop
per is coating of mercury and cyan
ide of potassium, and this coating de-
tains yet more of the gold dust Then
the stream moves over a stretch of
blankets, and the rough, hairy sur
face of these catch particles which
have evaded the seductions of the
bath and the copper plates Finally
the water falls into a deep pit, and
from this there Is no escape. Every.
thing mineral must sink to the bot
tom and remain. The idea Of the
whole series Is to detach the heavy
gold and to leteverything lighter pass
out into the pit. In spite of all eff
forts much of the precious metal
succeeds in reaching the final stage.
TO obtain the gold the mercury
bath Is empted, the coating carefully
scraped off the copper plates, the
blankets relieved of their load and the
sediment at the bottom of the pit re
moved and washed To get rid Of
the mercury the mass is put into a
retort and heated whereupon the
mercury takes to itself wings of va
por and flies away. TheIe remains
lump consisting of gold. copper, iron,
silica and small quantities OF other
elements too numerous to mention.
The law Of gravitaton, which has
done so much already, completes the
work The heterogeneous mass is
wetted, the gold sinks to the bottom,
and the base constituents form Stag
on the surface. The removal Of this
Stag leaves only gold behind.
Such, in brief, is the modern
method of work in Australia and
Africa to-day. There is not much
romance about it, but it is effective.
Even the -honored miners i'm
plement, the revolver, is now almost
unnecessary Gold diggers do not
sleep now with their head reposing on
a bag of dust clutching a pistol in
each hand. On the contrary, they
! inhabit comfortable houses and have
no fear of burglars Poetry has given
place to prose, but one sometimes
/ Lapttors ,ftor thu rt1 pno4rv ROMA II