The Colfax chronicle. [volume] (Colfax, Grant Parish, La.) 1877-1981, 1881-08-13

from various business houses. Itsome-
times happened that deposit of orig
inal dust, in small flaky grains, was
brought into the Office by bronze-faced
miner in person, who had brought it
home.
The method is to take the gold on de-
post from the bankers or others who
send it, and to give them check on the
Sub-Treasury after an assay had been
made. Each deposit OF gold is melted
and cast into bricks in every case be-
fore the ASSAY is made. Two small
quantities are then chisled off from two
different bricks and sent one to each
of two men in the assay room. Here
seven grains and halt of each quanti-
ty are carefully weighed out by each
man on separate pair of scales en-
closed in glass case. This seven and
half grains corresponds with a French
weight which has been divided into a
thousand equal parts. Each of the two
assayers works separately but in SIM
liar manner to the end of the assay.
Their results must agree to within
very small fraction. Each adds to the
weighed gold definite quantity of sill
yer. This is done because the nitric
acid to which it is to be subjected will
not ferret out very small quantities of
silver that are enveloped in the gold,
but if large amount of silver is melt
ed up with the gold the acid can follow
it into the mass and eat it all out. The
weighed particles of gold and silver are
then wrapped up in !. little sheet of
pure lead of known weight that is
first twisted into the shape of cornuco-
pia to receive them. This pellet of gold
and silver and lead is then melted in a
cupel, little porous white cup made of
the ashes of bone pith. A draft of hot
this oxydizes the lead, and the pres
ence of the oxydized lead for some un-
known reason aids the oxidation of the
copper mixed in the gold and carries it
down with it in a similarly mysterious
way into the pores of the cupel There
is left a little button of gold and silver
lying in the bottom of the cupel This
is hammered to knock off the scales of
oxide that cling to it, and then rolled
into n ribbon nearly half an inch wide.
This ribbon is coiled up and put into a
little platinum cup, the size of a Thin
BILE. and set into boiling nitric acid
The bottom of the platinum cup is per-
forated so that the boiling acid may en-
ter and get a fair chance at the silver.
1t will not attack either the
gold in the ribbon nor the plati-
mum in the cup. The coil is boiled
ten minutes, and then lifted out and
boiled ten minutes more in fresh acid.
BY this time the silver is all eaten out
of the ribbon, and the gold is left porous,
which makes it so brittle that if it is
pinched the little coil will crackle into
pieces in the fingers. 1t is accordingly
subjected to just enough heat to cause
the particles to adhere. This little coil
is now pure gold. 1t is unpublished and
of dull creamy, color. Not a particle
of the gold has been lost, but all of the
alloys have been removed. 1t is again
carefully weighed. Suppose that where
as it originally weighed 1000 according
to the system of weighing explained
above. it now weighs only 873. This
shows that the metal brought in to be
assayed contains S73 parts in 1000 of
gold, or, in other words, 81 $40 per
cent. of it only is pure. ~
All gold is melted before it is assayed
and having been assayed it must be
melted again in order to be refined. An
additional quantity of silver is added to
it for the same reason that has been ex-
planned in the process of assaying. 1t
is then melted and granulated by flirt-
ing the molten gold from ladle upon
the surface of water The idea is to
make the gold fall in sheet on the
surface so that it will break up into lit
tie flaky masses. This granulated gold
is then dried, and for convenience of
handling is pressed into cheese shaped
masses. These are cut up and the pieces
are put into boiling oil of vitrioi. The
acid eats out the silver and copper.
which turns it blue. This blue liquid is
drawn off with siphon. The boiling
is repeated several times, varying in
according to the purity required,
after which the gold is melted and run
into brick-shaped masses to be carried
to the treasure room. SOC 3a5 81.
The blue liquid which contains the
copper and silver is run into tank and
weakened with the addition of water.
The effect of this simple process is to
cause the acid to let 60 of the silver
while it yet clings to the copper.
I" If you have cat," said refner,
T" OF large size and good courage she
will clear the house of rats and mice;
but if you get asmaller cat, or one that is
not quite so courageous, she will lei
the rats run and coniine herself to the
mice. The mice in this case are rep
resented by the copper, which the acid
cuts up with greater ease than it does
the silver"
The blue liquid is now allowed to
stand in lead-Iined tank. in which are
also many long strips of
lead. On the lead beautiful blue crys-
tails are formed, with points as sharp
as needles, and whose scratch is poison
Gus. These crystals are blue vitriol, or
sulphate of copper. and are sold as such
for the making of Paris green and other
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