The Washington times. [volume] (Washington [D.C.]) 1902-1939, 1917-01-02
Imitation Brilliant May Scratch,
But viii Not Cut
Glass.
FILE WILL. SETTLE DOUBT
Facets of Genuine Stone Rarely
Cut So Perfectly as
False.

Far be it from us to plant IN the
trusting mind of any woman who
wears a diamond a horrid doubt as to
its genuineness; and should suspicion
already possess her the best advice
doubtless is to let sleeping dogs lie.
what YOU don't know won't hurt
your is a splendid working motto for
suspicious female.
However, there are a few tests for
determining genuine diamonds; S.
Leonard Bastin gives them in an
article published in a recent number
of the Scientific American:
Oldest Test.
One of the Oldest tests for a dia-
mond is, of course, the practice of
drawing it over a sheet of glass. The
popular idea that a paste article will
not make any mark is incorrect. Well
made imitation diamonds commonly
scratch glass, but they do not cut 1t.
A real diamond drawn quite lightly
over the surface cuts the glass
so completely that the slight
est blow will cause a separ0-
ton. Another old test is that in
which a file is employed. In the case
of a real stone it is impossible to
make any impression with the nipple
ment. An imitation article is easily
marked. Or the suspected gem may
be placed between two coins and
pressed hard with the fingers. 1t
will be impossible to make the small
est impression on a real diamond, but
! in the case of a paste article the
edges may be crushed. The effect can
| be discerned by a critical examine
ton with lens.
Water Test.
When a diamond is quite clean and
dry carry out the following expert
ment: Place on the surface a tiny
drop of water. Now take a needle
or pin and try to. move the drop
about. II the diamond is genuine the
drop can be rolled about intact. On
the other hand, where the gem is
an imitation the water spreads direct
| ly 1t is touched with the needle
| point.
Another very good test may be car
ried out with a tumbler of water.
Into this put the suspected article
and examine its appearance. A real
diamond will show up in the water
with startling clearness and 1t can
never be COMPOUNDED. with the water.
On the other hand, the imitation
! looks indefinite and il is sometimes
difficult to see 1t clearly at all.
Black Spot.
Make a single black spot on a
white card and hold the diamond in
front of this at distance OF about
a quarter of an inch. II the gem
is real the spot stands up quite plain
| ly. On the, other hand, in the case
of a spurious gem a ring of spots is
usually seen and these are often blur
red. Selected a piece of any fabric
with red and white stripes on 1t. Now
draw the stone which is being tested
over the colors. With an imitation
the colors will be plainly seen, while
with a genuine diamond 1t Is not pos
sible to see the tints.
Generally speaking the facets in a
real diamond are not cut so truly as
those In the imitation. This Is on &C.
count of the fact that diamonds are
sold by weight; hence the cutter tries
to preserve as much of the original as
possible, even making small sacrifices
in the matter of regularity. In the
case OF a paste article or a cheaper
stone no such need arises and the cut
ter endeavors to make the stone ap-
pear as perfect in shape as possible.
To observe such Irregularities as
sometimes occur in a real diamond IT,
Is needful to examine II with great
care.
Many diamond experts are able to
tell a false from a real gem by simply
h. fNAIA H..
the tongue. 1t is said that a genuine
diamond always feels noticeably
colder than a paste article.
Aluminium Test.
The test with an aluminium pencil
is worth trying, as this is commonly
regarded by experts as the surest of
all. Marks on glass or any similar
substance containing slick made with
an aluminium pencil cannot be re-
moved, no matter how hard they may
be rubbed. Even with the use OF acids
it is difficult to erase them entirely.
Wipe a suspected stone carefully and
then mark it with an aluminium pen
Gil. Now rub briskIy with a moist
ened cloth. II the gem is real the
mark will disappear at once. Where
the line remains II is certain that the
stone is not real.
Phosphorescence.
Finally. real diamonds are phospho-
resent after being treated in the fol-
lowing manner. FIRST OF all expose
for a few minutes to the light of an
electric arc lamp. Then rub briskIy
on wood or metal. Now take into a
dark place, when the diamond will