Akoya Pearls When people see the perfect white, round gem, the pearl most people think of is often an Akoya pearl. The Akoya oyster is the primary oysters used for saltwater pearl farming in China and Japan. The oyster is small, so most Akoya pearls aren't larger than 9mm. They are usually white or cream with hints of pink or green. They are the classic cultured pearls of Japan. They are the most lustrous of all pearls found anywhere in the world. In recent years, China has been successful in producing Akoya pearls within their own waters. However, they have not been successful with producing as brilliant a luster as high quality Japanese Akoya cultured pearls. They are the most difficult to produce because they have such low survival rates. Less then 5 out of 10 survive the nucleation process, 40% of the surviving pearls will encircle the shell nucleus irritant with nacre, and less than 5% of those pearls will be considered "high quality."