Cultured Pearl

[andrewmoquin]

A cultured pearl is a pearl created by a pearl farmer under controlled conditions.

A pearl is formed when some sort of small object, typically a parasite or piece of organic matter, becomes embedded in the tissue of an oyster or mollusk. In response, the mantle tissue of the mollusk secretes nacre. Chemically speaking, this is calcium carbonate and a fibrous protein called conchiolin. As the nacre builds up in layers, it surrounds the irritant and eventually forms a pearl. It is a myth that a grain of sand can cause a pearl to form as nacre will not adhere to inorganic substances.

Natural pearls are those pearls which are formed in nature, more or less by chance. Cultured pearls, by contrast, are those in which humans take a helping hand. By actually inserting a foreign object into the tissue of an oyster or mollusk, pearl farmers can induce the creation of a pearl. The same natural process of pearl creation takes place.

Modern-day cultured pearls are primarily the result of discoveries made in the late 19th and early 20th centuries by the Japanese researchers Mise and Nishikawa. Although some cultures had long been able to artificially stimulate mollusks into producing a type of pearl, the pearls produced in this way were only blister and mabe, rather than actual round pearls. What Mise and Nishikawa discovered was a specific technique for inducing the creation of a round pearl within the gonad of an oyster. This technique was patented by Kokichi Mikimoto shortly thereafter, and the first harvest of rounds was produced in 1916.

Source: http://www.amazines.com/cultured_pearl_related.html