Pearls differ in colour, size and shape based on the variety of the mollusc, growing conditions, harvesting techniques and other factors. Akoya, Cortez, Mabe, South Sea and Tahitian pearls are some of the most popular varieties, each of which has its own set of qualities. Akoya pearls are typically white or cream, but they can also be grey or black. Cortez pearls are available in a range of colours, including a shimmering black pearl. Mabe pearls possess a very high lustre, while South Sea pearls are among the largest cultured pearls and can be white, cream or Gold. Tahitian pearls are naturally grey, silver or black. The most sought-after Tahitian pearl is black with peacock green overtones.