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THE DIAMOND
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be
enticed could easily pay much more for a piece of the same value, for
some fancied superiority. So cleverly were these glittering displays
managed, that sufficient profits were made out of a foolish clientele
to pay the high rentals of stores in the most expensive locations, and
leave a large surplus for the managers.
In
the past, white sapphire, jargoon, white topaz, and rock crystal have
all at times been sold occasionally as diamond, but of late years
imitation diamonds, of whatever name, have been simply glass, for fine
specimens of sapphire and jargoon excepted, glass looks better long
enough to sell, than the other stones which though real, are not as
deceptive.
As
enormous quantities of them are used, much ingenuity has been
displayed in the manufacture of glass diamonds and the art has been
brought to a high state of perfection. The imitation of gems is as old
certainly as Egypt, but the fine white glass composition which with
some variations is used now, was invented in the seventeenth century by
Josef Strasser of Strasburg, and was called after him " Strass." It was
composed of silica, potash, borax, red-lead and sometimes arsenic. Of
the different proportions used now, the following is given as a good
example: 300 parts powdered quartz, 470 parts red-lead, 163 parts
potash (purified by alcohol), 22 parts borax, 1 part white arsenic, by
weight, This makes a dense white glass and is the mixture called strass
or paste, from which the fine imitations are made. Great care is
exercised in cutting the fine imitations, not only in the work of
faceting, but also in shaping and cutting to proportions which will
hide as much as possible the inherent differences of reflection,
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