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112
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NATURAL HISTORY OF GEMS.
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and
termed the Hyaloeides, which may mean the Beryl, a gem not mentioned by
him under that name. For, strangely enough, Garcias ab Horto asserts "
that no Crystal at all is found in India, but, on the contrary, the
Beryl in large fragments, out of which the natives make both glass and
vessels of price." The first part of this statement is altogether
erroneous, for Crystal is still brought from India, and in masses of
enormous size.
Glass
had been carried to such perfection when Pliny wrote as to imitate the
Crystal with wonderful exactness, yet, what surprised him, vases of the
latter substance had risen in value, instead of declining through this
competition. This colourless, transparent glass, approaching as nearly
as possible to the true Crystal, was then the most admired. Such
perhaps was the material of the two small vases with handles
(pterotae), a discovery of Nero's times, which sold for the enormous
price of 6000 sesterces (60?.), for Pliny quotes them when speaking of
this stone.
The
Indians (xxxvii. 20) had discovered the art of forging all the coloured
gems, but more especially the Beryl, by staining Crystal. Treatises
were extant, says Pliny (75), directing how to stain Crystal so as to
pass for the Emerald and other transparent precious stones ; hut he
declines to point them out, on the ground that even luxury ought to be
protected against fraud; adding that no other mode of cheating in the
world was so lucrative. Dutens, however (' Pierres Précieuses,' p. 67),
is less scrupulous; stating that a Crystal made red-hot and plunged
repeatedly into the tincture of cochineal becomes a Piuby ; if into
tincture of red santal, it takes a deep red tint ; into tincture of
saffron, a yellow like the Topaz ; into that of turnsole, it assumes
the colour of the Sapphire ; into juice of nerprun, it takes a deep
viole like the Amethyst ; and into a mixture of tincture of turnsole
and saffron, it be-
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