As many as 100,000 species of oysters exist in the world, but only 6 species such as the Pteriidae and Unionidae Families are used for cultured pearls. These oysters are called the mother oysters of pearls. While the exterior of all the oysters is plain and unattractive, the interior has the beautiful pearl-like luster. At pearl culturing farms in Japan, Akoya pearl oysters are most widely cultivated and a very small number of black lip pearl shells. Ikechogai, freshwater mollusks, are also used for cultured pearls.

Mother oysters for "Wadama", beautiful fine-textured rose pearls. Breeding with pearl oysters of different localities is being conducted to improve quality.

They are cultured in the eastern part of Biwa Lake and Kasumigaura. In the wild, these mussels are in danger of extinction.

Mabe often refers to a half pearl in general, but strictly, it means pearls of large winged pearl shells. Maybe pearls have a unique iridescent luster.

These are the only pearls from non-bivalve oysters. They are used for cultivating half pearls.

Mother oysters of large pearls called the "South Sea Pearl." There are two types, one has a silver margin on the interior, and the other a gold margin. They grow in the eastern Indian Ocean and the southewestern Pacific area between the tropic of Cancer and the tropic of Capricom.

The shells form beautiful black pearls resembling the color of peacock feathers. They are cultivated in Ishigakijima Island and Iriomotejima Island in Japan.