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Old as it is, the Chinese culture of pearls left much to be desired.
In the latter part of the past century Dr. Mitsukuri, of the Imperial
University of Japan, advanced a new theory in pearl culture. Working on
this theory, Kokichi Mikimoto began experimenting in 1891 using
spherical mother-of-pearl beads as nuclei. At the St. Louis Exposition of
1904 Mikimoto exhibited some of his cultured pearls but these,
unfortunately, were attached to the shell. It was not until 1913 that he
perfected his process. Since then hundreds of technicians have been
trained and it is said that Mikimoto now has a surplus of 10,000,000
culture pearls. (1) (2)

The cultivation of pearls requires great skill and patience. The
Japanese found that the best pearls came from the strongest oysters so
they began improving their strains by careful breeding. The collected
spawn is frequently examined for disease during growth. Young oysters
are placed in fine-meshed cages, designed to protect the young shells
from the attacks of star-fish and other enemies, and lowered into the sea.
Until they are two years of age the young oysters are repeatedly
examined and their cages cleaned. Then they are moved to wider-
meshed cages for another year. (1)

At the age of three years they undergo an operation which
transforms them into pearl bearers. After removing one shell of an
oyster, a mother-of-pearl bead is placed on the epithelium of the mantle.
The skin is cut away and made into a ligatured sac which is then grafted
into the sub-epidermal tissues of another oyster. The ligature is