White South Sea cultured pearls are created in large Pinctada maxima mollusks which can be up to forty centimeters long. This oyster is one of the largest of the thirty or so kinds of oysters found around the world. These are the only hosts which can grow the large and truly magnificent pearls with diameters of up to 20 mm.

Photo: Necklace with large, symmetric white South Sea cultured pearls.