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
The Pearl (novel) The doctor also visits, and although Coyotito seems to be healing, the doctor insists that Coyotito still faces danger and treats him. Kino tells the doctor that he will pay him once he sells his pearl, and the doctor attempts to discern where the pearl is located (Kino had buried it in the corner of his hut). That night, a thief attempts to break into Kino's hut, but Kino drives him away. Juana tells Kino that the pearl will destroy them, but Kino insists that the pearl is their one chance and that tomorrow they will sell it. The next