CULTURED PEARLS Made famous by Mikimoto, nearly all pearls sold on the open market are cultured. Cultured pearls evolve in a similar manner as natural pearls, with the distinction being that cultured pearls have an irritant intentionally placed by a pearl farmer to start the formation of a pearl. The process may take one to several years. Japan, China and various places in the South Pacific have traditionally been major suppliers of cultured pearls. All pearls sold on this website are cultured pearls.