had
no less than four splits in the base or " collet," and one small one
half-way across the "table." These flaws detracted but little from the
stone's appearance at night, but on comparing the stone with a perfect
one, their effect was only too apparent.
First-class
imitations command a good price, owing to the cost of their production;
the materials, time and skill required for making the rough glass
alone, without taking into consideration the expense of cutting and
polishing, all tend to keep really fine examples of this class of work
from becoming cheap. Yery cheap forms of paste are to be purchased, but
they will not stand comparison with better qualities.
Although,
strictly speaking, pearls do not belong to the mineral kingdom, it may
not be out of place in an article of this nature to mention briefly the
method of making imitations. They are so perfectly made, besides being
not quite so perishable or liable to decay as real pearls, that the
latter as a consequence have fallen very considerably in value. Tbey
were first imitated by Jacquin at Paris in 1656, and the method in
vogue to-day is much the same as that he discovered. It consists in
blowing small spheres of opalescent glass coated internally with a
preparation known as "Essence d'Orient," made from the scales of such a
fish as the Bleak. The sphere is slightly dented, coated externally and
internally with parchment size and pearl essence, and then filled in
with wax. Pearls imitated in this way are exceedingly beautiful, and
have a rich and charming lustre. They may be known by their hardness,
which is very much greater than that of real pearls, and by their
extreme hrittleness, the slightest pressure causing
