Pearl human intervention. They are quite small, typically only a few millimeters. Keshi pearls are produced by many different types of marine mollusks and freshwater mussels in China. Keshi pearls are actually a mistake in the cultured pearl seeding process. In seeding the cultured pearl, a piece of mantle muscle from a sacrificed oyster is placed with a bead of mother of pearl within the oyster. If the piece of mantle should slip off the bead, a pearl forms of baroque shape about the mantle piece which is entirely nacre. Therefore, a Keshi pearl could be considered superior to cultured pearls
Pearl of Kuwait at the Victoria and Albert Museum in London, which closed on 19 January 2014. Its owners have made claims that it is the same pearl that is depicted in the portraits of Mary Tudor. The Pearl of Kuwait outweighs La Peregrina by a small amount. The pearl is currently on loan to the Smithsonian, who make no claims of its history or provenance. The Smithsonian does say that it is exceptional, that is weighs 64.4 carats, that its setting is 19th century in style, and that the pearl itself "recalls" those that originate from the Persian Gulf. Pearl of Kuwait