Amongst all nations Pearls have ever been considered the most beautiful products of Nature, but having their origin in a living organism cannot be called a precious stone. Most scientists are agreed that Pearls are formed in the endeavour of certain bivalves to obtain relief from the irritation caused by some foreign substance which has penetrated the shell and which the Oyster, by covering with a pearly secretion, forms into a beautiful gem.

The idea that Pearls are symbolic of tears arose from this fact, and illustrates the old adage that the most noble achievements have their origin in painful and enduring effort. Nowadays in the Pearl Fisheries, particularly in the Bay of Ago, (Japan,) foreign matter is intentionally introduced into the shell, but the results do not equal the Pearls found as the outcome of natural influences, a considerable time being required to bring them to perfection.

Pearls are extremely hard, and the well-known story of Cleopatra's Pearl cannot be believed, unless the Pearl was first ground to powder, as any acid sufficiently strong to dissolve a Pearl would be fatal to human life.

Among Eastern nations this gem is credited with the power of preserving the purity of their wearers, and as an emblem of maidenly purity. The Romans also set a high value on Pearls, consecrating them to Isis, and wearing them for her favours. Pearls were also made into a decoction with distilled water and given to lunatics to restore their reason. In China Pearls are powdered and taken as medicine for syncope and stomachic ailments.

The occult properties of the Pearl in olden times caused them to be worn as Amulets by divers as a protection against sharks.

This gem is, however, considered unfortunate for those in love, and if worn by the married signified "torrents of tears," and for this reason is seldom used in engagement rings, even at the present day.