Cultured pearls can be broken down into two major categories - Freshwater cultured pearls and Saltwater cultured pearls. Within these two categories you will find a large variety of shapes, sizes and colors.
There are 3 categories of Salwater Cultured Pearls: Akoya Pearls,South Sea Pearls, and Tahitian Pearls. Saltwater pearls are much higher in quality then Freshwater pearls but also much more expensive. Saltwater Pearls are more lustrous and tend to be rounder.
For many years, pearl divers have brought up beautiful gems in the waters of the coasts of Japan Mexico , Sir Lanka, and the Persian Gulf. Their quarry was few and far between, but they never knew which oyster might hold the key to making them, or even their entire village, rich They were lucky if they found one pearl in a thousand oysters.
Saltwater cultured pearls come from the Akoya oyster. Mikimoto pearls (Mikimoto is the name of a company, not a type of pearl) come from the Akoya oyster and are the best known saltwater cultured pearls. Akoya pearls are the most difficult to grow due to the low survival rates of the host oysters. Less than 5 in 10 will survive the nucleation process. Of the survivors, about 40% will successfully encircle the shell nucleus irritant with nacre. Overall, less than 5% of pearl output can be considered "high quality."
