nesia and allowing it to dry on them. When this is removed, the pearls will often be found much purer in color than before.
In
various parts of the world certain dubious methods have been used for
restoring the beauty of pearls which have grown dim. In India they are
rubbed in boiled rice. Some persons have even fed them to a chicken
fastened in a coop ; after the lapse of an hour or two the chicken is
killed, and the pearls rescued from their temporary lodging-place,
where they have been somewhat restored by the digestive juices of the
fowl.
Some
curious tests applied to pearls are given us in a Hindu treatise on
gems by Buddhabhatta. For instance, we read: "If the purchaser
conceives a doubt as to the genuineness of a pearl, let him place it
during one night in a mixture of water and oil with salt, and heat it.
Or let him wrap it in a dry cloth and rub it with grains of rice ; if
it do not become discolored, it should be regarded as genuine."1 It is needless to state that these tests would be either useless or injurious.
If
the reader is the owner of a pearl or of a pearl necklace and feels
that the pearls need treatment, any attempt to follow the directions
given by many ancient writers would infallibly result in their injury
or destruction.
Pearl
drilling is a most delicate operation. It is necessary that the drill
points should have the proper shape,—that is, should not be too
tapering, but slightly blunt at the end, and turning somewhat in a
V-shape,—it is also important that the drill should be revolved with
perfect regularity, so as not to jar or jolt the pearl, as this is
likely to lead to the cracking of the pearl or to the breaking of the
drill. This latter happens not infrequently, and is due either to the
structure of the pearl, the clogging of the drill, or to encountering a
hard grain of sand inclosed in the pearl. Should the drill break in the
pearl, it can best be removed by drilling from a point directly
opposite, and slowly forcing the broken drill outward. This process
requires great care in the regulation of the speed, and great exactness
of direction in order to meet the broken drill accurately.
Pearl
drilling was formerly a laborious process, and it was scarcely possible
for a driller to perforate more than from forty to fifty pearls per day
by means of the bow-drill operated by hand. Now, by the use of a modern
machine, 1500 pearls of average size can be drilled without any
difficulty in the same time.
Some
of the most successful drilling of fine pearls is done by means of the
bow- or fiddle-drill. The arm of this is made either of steel or of
wood, with a strong cord stretched across it in the style of an
archer's bow. The drill is inserted in the end of a brass circular disk
Finot, "Les Lapidaires Indiens," Paris, 1896, p. 24.
