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PRECIOUS STONES.
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from the scales of the bleak or ablette, a little white fish which abounds in the Seine, the Marne, and the Loiret.
The
fishes are rubbed rather roughly in pure water, contained in a large
basin; the whole is then strained through a linen cloth, and left for
several days to settle, when the water is drawn off. The sediment forms
the essence of orient. It requires from 17,000 to 18,000 fishes to obtain 500 grammes (a little over a pound) of this substance.
The
scaly substance is liable to decompose quickly, and numerous chemical
agents are employed by different manufacturers to preserve it. These
means are kept a secret, but it is known that liquid ammonia, or the
volatile alkali, is one of the substances most commonly used.
The
process of colouring the pearl is commenced by lining the interior of
the ball with a delicate layer of perfectly limpid and colourless
parchment-glue; and before it is quite dr.y, the essence of orient is
introduced by means of a slender blowpipe. It is then allowed to dry;
the pearl is filled with wax, and, if intended for a necklace, is
pierced.
FALSE CORAL.
A number of objects are made at the present day of a composition intended to resemble coral, but
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