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 of Lao Tzu pearl was estimated to achieve $300,000 to $400,000, but it was not sold. Pearl of Lao Tzu The Pearl of Lao Tzu (also referred to as Pearl of Lao Tze and previously as Pearl of Allah) used to be the largest known pearl. The pearl was found in the Palawan sea, which surrounds the island of Palawan in the Philippines, and was found by a Filipino diver. It is not considered a gemstone pearl, but is instead known as a "clam pearl" or ""Tridacna" pearl" from a giant clam. It measures 24 centimeters in diameter (9.45 inches) and weighs 6.4