Types of Cultured Pearls
Pearls will vary depending on the species of mollusk that produced the pearl and the environment in which the animal lived. The main groups of cultured pearls produced today are:
• Keshi Pearls (this is a by-product which can arise from any of the above groups)
To produce a cultured pearl a technician skillfully inserts foreign matter into a healthy, mature oyster or mussel. To protect itself from this irritant, the oyster produces cells that secrete multiple layers of nacre that eventually coat the foreign matter to become the cultured pearl. After the insertion, the oyster is placed in wire?mesh baskets for protection and hung from floating rafts in the sea. Traditionally, after one to three years beneath the sea the pearls are then harvested.
The shape and size of the resulting pearls depends, to a large degree, on the shape and size of their implanted irritant. Finding a valuable pearl requires as much luck as skill. The number of gem quality or 'perfect' pearls produced each year is still remarkably low.