Pearls are unique in the gemstone world because they are the most precious organic gems. They are not created in the earth's crust, but rather in the soft flesh of an oyster. For most of human history, pearls have been extremely rare and expensive. However, in the last century, methods of pearl cultivation have been developed that make fine pearls more accessible to everyone. Pearl is the birthstone for June and used for the 3rd and 30th anniversaries.