Gorgeous Genuine Natural Freshwater Pearl Necklace With Bow Shaped Silver Plated Clasp Brand New Without Tags Cultured White Freshwater Pearl, 3A grade Length Necklace: 18 in Pearl Shape: Potato Approx Pearl Size:  7-8 mm Findings: Silver Plated Clasp Tarnish Resistand Pearls are the only gems that are produced by an animal. Cultivators mimic the way natural, uncultured pearls are created by implanting a beadlike nucleus from a mollusk shell into an oyster, and the animal responds to the irritant by coating it with a pearlescent nacre of calcium carbonate, layer by layer, multiple times per day. In this article the sizes and shapes of freshwater cultured pearls are approximate, therefore no claims are accepted for this reason. To preserve this jewel, it is recommended not to expose it to direct contact with creams and perfumes.