Atlanta semi-weekly journal. (Atlanta, Ga.) 1898-1920, 1902-09-08
TESTS OF DIAMONDS.
Simple But Scientific Ways of Judging
Gems.
London Express.

London Express.
Any one can tell genuine diamond or
precious stone even from very clever
imitation. There are few household tests
which are practically infallible. The, dia-
mond expert, after long years OF expert
ence with gems. can detect an imitation,
as a rule. at a glance. The laymen In
such matters, with a few simple tests,
takes more time to solve such problems,
but his judgment in the end is scarcely
less accurate.
An imitation diamond is never so brill
liant as a genuine stone. If your eye IS
not experienced enough to detect the dif-
ference a very simple test is to place the
stone under water. The imitation stone is
practically extinguished, while genuine
diamond sparkles even under water, ana
is distinctly visible. When possible place
a genuine stone beside the possible imita-
ton under water and the contrast will be
apparent to the least experienced eyes.
The glass-cutting test is, of course, more
or less familiar. 1t is probably the most
common False diamonds are usually cut
more regularly than the genuine stones.
In cutting a diamond the material is
saved as far as possible. In any imitation
the material is itself worthless, and no at
tention is made to suit the size or angle
of the facets to the form of the stone. II
can be put down as a safe rule that when
a stone is cut with great evenness and
regularity it is, to say the least. a very
suspicious sign.
Another very simple and effective test is
90 place q drop of water on the stone and
carefully observe the result. The stone
should first be carefully cleaned. On an
imitation diamond the drop, however
small, will deliquesce. The drop will, how
ever, retain it's original shape on true
stone. To make the test quite sure use
magnifying glass when watching the &C
ton of the drop.
Still another test of this nature Is to
pass the stone over a piece of aluminium.
Both the metal and the stone should be
absolutely free from any trace of grease.
The metal will give off some of its color
to an imitation stone, while a genuine dia-
mond will remain perfectly clear and I'M
affected. Among jewelers. the final test is
to apply a drop of fiuorhydric acid to the
stone under suspicion. The acid VIII eat
into any false diamond and frost 1t, while
the genuine stones will not be damaged in
the slightest degree.
Perhaps the simplest method Of all, how
ever, is to examine an ink spot on
sheet of white paper through diamond,
by holding the upper surface against the
eye If the stone be counterfeit the black
spot will appear greatly multiplied, or at
least doubled. The outline will, moreover,
appear blurred and indistinct. BY using
magnifying glass the test can readily be
made absolute.
The optical test is the best in examining
rubles and emeralds. 1t Is commonly sup
posed that such stones can be best tested
by rubbing them with file, that the gen.
uine stones resist the steel. while the imi-
tations only will suffer; but the test is not
exhaustive. The best plan is to examine
them closely with a microscope Of about
100 diameters. The genuine stones have
number of minute flaws, whereas the imi-
tations are likely to be much more nearly
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