False Precious Stones.
" Art,
aping Nature, eager to deceive, Has learnt to imitate the jewel true
With lying glass, and thus beguile the view. Hence hard the real gems
from false to know. When pastes with imitative colours glow. Their
boasted virtues soon as tested fail. And hence discredit does the true
assail. Yet the true gem, by sages duly blest. In wondrous works its
power will manifest."
Under
the name of false precious stones, there arc two kinds of productions
which are essentially different—the one natural, the other artificial.
The
first comprehends stones sufficiently hard to resist the file; they are
generally quartz, either hyaline or variously coloured.
The second consists of artificial compositions of the nature of glass.
There
is an intermediate order, the productions belonging to which, if well
executed, are especially calculated to deceive, and are used to great
extent in the East Indies. They are called semi-stones, or doublets.
