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
The Thirteenth Pearl go to Japan. They finally kidnap her and her boyfriend, Ned when they return to River Heights. Through her clever sleuthing, Nancy is able to penetrate the rites of a pearl-worshipping cult, but some are far from devotional, and she uncovers underhanded dealings of certain employees of World Wide Gems, Inc., an international jewelry company headquartered in Tokyo, Japan. The Thirteenth Pearl The Thirteenth Pearl is the fifty-sixth volume in the Nancy Drew Mystery Stories series. It was first published in 1979 under the pseudonym Carolyn Keene. The actual author was ghostwriter Harriet Stratemeyer Adams. "The Thirteenth Pearl" is the