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 Pearl of Death The Pearl of Death The Pearl of Death is a 1944 Sherlock Holmes film starring Basil Rathbone as Holmes and Nigel Bruce as Dr. Watson, the ninth of fourteen such films the pair made. The story is loosely based on Conan Doyle's short story "The Adventure of the Six Napoleons" but features some additions, such as Evelyn Ankers as an accomplice of the villain, played by Miles Mander, and Rondo Hatton as a brutal killer. Master criminal Giles Conover (Miles Mander) steals the famous "Borgia Pearl" from the Royal Regent Museum under the very nose of Holmes and Watson, but