Australian Cultivated white Pearls Necklace. N. 31 perfectly round pearls, mm. 13 x 16, total weight 640 cts. Notes: South Sea pearls generally have a diameter far greater than other types of pearls produced in the world. They have a unique quality and shine of their kind. These factors make Australian pearls distinct and rare. Their shortage dictates their prices which are higher than all other types of pearls. Like other types of seawater oysters, the “Pinctada Maxima" is nucleated, that is, a nucleus is inserted. The period of growth of pearls is from 3 to 6 years, in comparison with Akoya oysters which take half the time to produce a pearl. These pearls live in an agitated water environment that makes mollusks more sensitive than their cousins in the seas of Japan and China. They are more prone to disease and the risks of oceanic disturbances. It is the reason why the cultivation areas of these oysters are more limited. Attempts to develop production by expanding the areas ended in failures since the "Pinctada Maxima" can only develop in certain environmental conditions. They are therefore collected in a well-defined area and carefully monitored. All this generates their phenomenon of rarity and luxury.