Evening star. [volume] (Washington, D.C.) 1854-1972, 1905-12-24
BOGUS GEMS, HOW MADE
AN INDUSTRY THAT REQUIRES
LARGE CAPITAL.
Methods of Turning Out Paste Dia-
monds-How Cut and
Polished
From london Tlt-Bits.

From London TIt-Bits
The passion for precious stones which has
reisned in the minds of and women
almost from time imniemorial has. of
course, given rise to much eounterfeiting of
the more valuable stones
All are more or less familiar, with the
cheap glass limitations where the worthless
ness of the article is so apparent that there
is no suggestion of fraud. Few however,
realize to what an extent skilled fraud ex-
lists in this trade more especially on the
continent, where much of the diamond cut
ting is done The manufacture of imitation
gems of specially prepared glass is quite
an important industry.
1t is now possible to produce I'm paste an
imitation of almost every precious stone
which is capable of deceiyfng the eyes of
all but the most expert Not only is there
a superficial resemblance but a skillfully
prepared paste" stone exhibits the same
lpster and high index of refraction and dis
pcrsion would diamond of the first
water The purity of the materials en-
ployed is such that equal degree of clear
ness and Transparency Is given TO the imi-
tatIon as is found in the genuine stone.
Color is initiated also, 20 that a ruby en-
erald, sapphire or other gem made of glass
Is practically indistinguish able from the
real jewel which may have cost hundreds of
pounds.
The material of which these imitation
stones are made is known as ''strass.. This
Is made according TO different recipes. but
usually includes red lead, rock crystal.
potassium carbonate, borax and white
arsenic. The greater the amount of lead
used In the production of the paste" the
greater will be the brillianey and play of
prismatic colors in the finished stone, and
at the game time the higher will be its spe-
cffic gravity. On the other hand. the stone
loses In hardness what 1t gains in briiEance.
An old-time, but stiil servieeahie, rough
i.-s
it will scratch or cut window glass, which
is as rule, harder than most imitation
stones.
Expensive Process.
1t must not be imagined that these close
limitations of the real diamond or other
stone can be produced cheapy. This is far
from the case A large capital is required
IL the manufacture and the high degree
OF purity necessary in all the materials
employed necessitates an amount of care,
and incidentally waste, which is exceed.
ingly expensive. Moreover. the imitation
gems have to be cut and finished in pre-
cisely the same manner as the real stones.
and this is perhaps the most expensive part
of the procedure.
Another method OF deceiving the unwary
purchaser of precious stones Is to palm
OF on him genuine stoaes which have been
faxed In some way 70 make them appear
more valuable than they really are. A
device commonly prActieed is that OF
cernenting two stones so that they appear
TO be one large one. At first sight there
does not seem 10 be any object In such q
proceeding. but diamonds increase very
much In value If they are large. For in
stance while E10 would be a very fair
price for diamond Weighing one carat
ESQ might be paid for five carat stone
of the same water.
Eastern jewelers. are particularly slsfIfui
in this direction. An Indian dealer will
think nothing OF selling for large sum a
beautiful stone which on examination by
an expert proves 10 be, perhaps, only
sldlsfnlly prepared piece of bottle glass. II
Is not OF course. claimed that there IS
necessarily anything fraudulent In the skill
full preparation OF imitation stones to re-
semble more valuable gems. Many Of the
most reputable jewelers. deal In these stones,
ehargfng price for which no one would