Freshwater come in a variety of shapes and sizes. They are found in lakes and rivers around the world and tend to be less expensive than their saltwater cousins, which make them a popular choice among young and trendy folk who don’t have the means to invest in pricier Akoyas or South Sea pearls. Among the many types of freshwater pearls are the Mabe Pearl, a half-spherical cultured pearl grown on the inside shell of a mollusc, the Biwa Pearl, which is grown at Lake Biwa in Japan, and the Rice Pearl.