Cultured pearl Cultured pearl A cultured pearl is a pearl created by an oyster farmer under controlled conditions. Cultured pearls can be farmed using two very different groups of bivalve mollusk: the freshwater river mussels, and the saltwater pearl oysters. A pearl is formed when the mantle tissue is injured by a parasite, an attack of a fish or another event that damages the external fragile rim of the shell of a mollusk shell bivalve or gastropod. In response, the mantle tissue of the mollusk secretes nacre into the pearl sac, a cyst that forms during the healing process. Chemically speaking, this
Pearl River (China) as the Pearl River just north of Guangzhou. The Pearl River is famed as the river that flows through Guangzhou. The Pearl River's estuary, Bocca Tigris, is regularly dredged so as to keep it open for ocean vessels. The mouth of the Pearl River forms a large bay in the southeast of the delta, the Pearl River Estuary, the Bocca Tigris separates Shiziyang in the north, Lingdingyang in the south, and Jiuzhouyang at the southern tip of the estuary surrounded by the Wanshan Archipelago. This bay separates Macau and Zhuhai from Hong Kong and Shenzhen. The Pearl River is so