Tahitian Pearls, also called black pearls, are formed from the black lip oyster, in saltwater. As with other saltwater varieties, Tahitian Pearls are grown by the insertion of a bead into the oyster. Cultured Tahitian Pearls are formed in a wide variety of shapes including teardrop, round, oval and baroque. While the variety is called the black pearl, they grow with a variety of secondary tones, ranging from light to very dark. Silver, green, blue, pink, yellow and copper are all colors that can be detected within these iridescent gems.