Buy Natural South Sea Pearl Online in Delhi. Purchase pearl stone (Moti) at Gemsndiamond online! With a FREE gem certificate, Gemsndiamond offers a huge selection of high-quality natural pearls for purchase. Natural South Sea Pearls are generally much larger than other pearl types and have a unique luster quality – a soft reflection due to the large aragonite platelets that make up the pearl. They also have the thickest average nacre of all cultured pearls. These factors make South Seas both distinctive and valuable.