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
City of Pearl and Aras, as she struggles to lead a mission whose goal she doesn't yet consciously know. "City of Pearl" is the name humans have given to a Wess'har city located on planet Wess'ej. Josh Garrod's predecessor, Benjamin, who was taken to see the city by Aras, was said to have wept at its beauty. Many of the people of Constantine relate it to heaven, despite Aras' insistence that the City of Pearl is "just a city." On Planet Earth, Superintendent Shan Frankland (A hardened, self-sufficient, and brutally honest female cop) is preparing for retirement when she is confronted by politician