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
Pearl (given name) been inspired by the name Margaret, which means "pearl". In Nathaniel Hawthorne's 1850 novel "The Scarlet Letter", heroine Hester Prynne names her illegitimate daughter Pearl because the child is "of great price, purchased with all she had, her mother's only treasure." The passage refers to the Parable of the Pearl in the New Testament. The gates to Heaven are also commonly pictured as made of pearl. It was among the 50 most popular names for girls born in the United States between 1880 and 1911, remained among the top 100 most popular names for girls between 1911 and 1926 and