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 of Love and colder" "sense of colour", and, wearying "altogether of carvings and pictures and inlaid ornamentation", has them "put aside". The prince comes "to care . . . more and more" for "a great aisle" that permits "a vista" of, "the snowy wildernesses of the great mountain, the lord of all mountains, two hundred miles away." All who look upon the Pearl of Love are "exalted", yet the prince feels that, "The Pearl of Love had still something for him to do . . . before his task was done." He realizes that the problem is "a certain disproportion about the