Western liberal. (Lordsburg, N.M.) 1887-1919, 1895-01-11
A BAR OF PURE GOLD.

Uncle Sam is preparing a standard
for pure gold, according to the ST.
Louis Globe Democrat. Il will take
the form OF a bar Weighing so ounces.
This bar will be cut into several pieces,
ono OF which will be given to each Of
tA United States mlnts and assay Of
ices. A slice will also be sent to
England for comparison with the
British standard Of pure gold.
1t seems thatno absolutely pure gold
has ever been produced ia this coun-
try--at all events, none Of which there
can be a certainty. The standards
now possessed by the various mlnts
differ somewhat; not one Of them is
surely free from impurity. For the
purpose of exactness 10 assay work, it
is desired to have a standard that is,
as Caesars wife should be-aboye
suspicion.
The bar that is to be is now a liquid
The so ounces Of gold are in a chemi-
cal solution at the mint in Philadel-
phla. The yellow metal thus dissolved
was extra tne to begin with, having
only one-fourth Of one per cent. of i'm
purity. The impurity was chiefly sill
yer. This gold was rolled to very thin
sheets and then put into q tank of
aqua regia and hydrochlorio acid.
The solution OF gold made in this
way was diluted with 20 gallons of
distilled water In that condition it
now remains, a thin, but precious
liquor. Under the action OF the acid
the silver fails down to the bottom CT
the tank ID white cloud At the
end of the month the clear liquid will
be drawn off carefully into TASKS, with
out stirring, so as TO leave the silver
impurities behind. Sulphurous acid
gas will then be passed through the
solution, causing it TO throw down the
pure metallic gold.
But many processes have yet to be
gono through before the gold will be
considered chemically pure. 1t will
be washed with distilled water, boiled
with hydrochloric acid, dissolved in
aqua regia, evaporated almost to dry
ness, diluted with water and precipi
tated in metallic form by oxalic acid
All this will then be repeated Final
~ the gold will be collected, melted
in porcelain crucible and made into
bar. The piece OF the bar that IL
sent to each mint will be compared b.
chemical tests with the standard o
pure gold now used at that mint.
Uncle Sam maintains many chemi
cal laboratories. There are a dozen il
Washington, attached to the various
departments. The mints do mucl
chemical work incidental to the assay
ing and refining of metals for coinage
The gold is refined by smelling it will
three times its weight of silver anC
placing it in kettles with sulphur,
acid. The acid dissolves the silve
and other metals that are mixed will
The gold, but does not affect the golC
itself, which is left ab the bottom o
the tank in the shape of brown pow
der The solution Of silver, ETC., being
drawn of, the pure gold is washed
with water and melted into bars. Th'
silver is recovered from the solution
by immersing in the latter large ingot
of copper, on which the silver is de
posted by the acid. The metallic sill
yer is then washed off the bars ant
melted into bricks.
This is the way in which the gold
and silver are got from the raw bullion
for making the coins OF the realm. Al
the Treasury in Washington isa labor
atOry where sample coins, taken from
leach piece are subject to analysis
Other metals which commonly arr
found as impurities with gold arr
platinum, copper, lead and iron. II
order laa5 r1t trace of any Of thes,
shall remSin in tue standard bar, NJ
chemical precautlon must be neglected