Cultured pearl is calcium carbonate and a fibrous protein called conchiolin. As the nacre builds up in layers of minute aragonite tablets, it fills the growing pearl sac and eventually forms a pearl. Natural pearls are formed by nature, more or less by chance. On the other hand, cultured pearls are human creations formed by inserting a tissue graft from a donor oyster, upon which a pearl sac forms, and the inner side precipitates calcium carbonate, in the form of nacre or "mother-of-pearl". The most popular and effective method for creating cultured pearls are made from the shells of freshwater river mussels
Pirates of the Caribbean: The Curse of the Black Pearl Jack Sparrow comes to Port Royal to commandeer a ship, and rescues Elizabeth. Norrington identifies Jack as a pirate, and a chase ensues. Jack encounters Will, now a blacksmith and swordsman. They duel, and Jack is captured and imprisoned. That night, the "Black Pearl" attacks Port Royal in search of the medallion. The crew of the "Pearl" capture Elizabeth, taking her to meet Captain Barbossa. Elizabeth claims her last name is Turner to conceal her identity as the governor's daughter. She learns that her medallion is one of the gold pieces that Barbossa's crew took from a treasure of Hernán