Evening star. [volume] (Washington, D.C.) 1854-1972, 1890-06-14
TESTING UNCLE sANI,s COINS.
How the Government Assayer Makes
Sure of Their Quality.

You would be amused to see the silver
dollars that compose the stock OF the govern
ment assayer at the Treasury building. Each
one of them is about foot long, of a mar
row oval shape, and perforated with hundreds
OF little round holes. Such is the form they
appear IN after being rolled out thin and
punched with a machine. All the silver coins
that come to the department for testing are
treated in this way to begin with. They are
sent III from the minis specimens, taken at
random from every fresh lot made. and il is
the duty of the assayer TO find out whether
these samples are of the weight and fineness
required by law. The weight is merely mat
ter of a moments trial on scales, which are of
such wonderful delicacy that single hair an
inch in length will altogether overcome the
equipoise, but to discover the degree OF fine
ness, which means the proportion of pure
silver in the coin, is a more difficult affair 1t
is decreed that the dollar. for instance. must
be exactly nine-tenths silver. the remaining
tenth being copper. and a variation of not
more than one and one-half grains in the
quantity OF the noble metal is allowed.
Why 1T Is ROLLED OUT.
The silver dollar has to be rolled out thin in
machine to begin with. because when the
coin is made the silver in it has a tendency to
go toward the middle, SO that the metal on
the outside Is not so fine as within. But the
assayer must discover the average fneness of
the piece in order TO ascertain Just how much
silver there is altogether al IT. and he does this
III very curious way. He passes the thin
strip of metal into which the dollar has been
rolled through little continuance operated by
crank that is turned by the hand The strip
comes out punched as full of holes as it can be-
while hundreds of small circular disks about
the size of a gold quarter dollar fall out of the
holes thus made into tiny box below. Next
! the disks are taken out of the drawer
ana mixed up; few OF them are
taken from the lot and they. representing
the average of silver, are subjected to cheml-
cal analysis. The director of the mint is
charged with the coins he receives from the
minis for testing in this way, and he sells back
to the minis the perforated strips and disks
thus squaring that account. 1t is the same
with halves and quarters and dimes as with
dollars. But these subsidiary CONS are not
worth as much in proportion TO their legal
tender value as the dollar. Two silver halves
are worth about five cents less than one silver
dollar: four quarters likewise and ten dimes
the same way. The government makes about
% per cent on all the money il coins in silver
through the fact that there is not a value of
SILVER In the coins equal to what they pretend
to be worth.
GOLD COINS,
however are worth their full face value in
gold, without counting the cne-tenth part of
copper they contain. The yellow metal, un-
like the silver. does not ''segregate'' in the
middle of the piece Therefore il is not
necessary to perforate gold coins for testing
them. They are simply rolled out, each strip
cut into three pieces. and little pieces for
chemical analysis are shipped off the cut
edges. There is a very small amount of silver
left in the gold pieces, as they are made at the
minis. and, for the sake of arriving at perfect
accuracy, the assayer takes this out by boiling
in nitric acid. The silver and gold sent back
to the minis for sale are melted up by the
Ouantity in "A hip