This stunning sterling silver art deco necklace features a diamond shaped mother of pearl gemstone, above a diamond shaped black onyx stone decorated with sparkling marcasite.This chain is 45cm long with a 3cm extender.Black onyx is a member of the chalcedony family and has been used in jewellery for centuries, most notably in ancient cameo jewellery.Mother of pearl, also known as nacre, is an iridescent blend of minerals that are produced by oysters and some other molluscs.Once used as a substitute for the shine of a diamond, the natural semi-precious gemstone marcasite is now celebrated for its lustre and metallic beauty.Black Onyx Information: Number of Stones: 1 Stone Shape: diamond Stone Size: 18mm x 5mm Carat Weight: 1.00ct Natural/Created: Natural Onyx Country of Origin: Brazil Mother of Pearl Information: Number of Stones: 1 Stone Shape: diamond Stone Size: 5mm x 3mm Carat Weight: 0.25ct Natural/Created: Natural Mother of Pearl Country of Origin: Australia marcasite Information: Number of Stones: 2 Stone Shape: Round Stone Size: 1.30mm Carat Weight: 0.03ct Natural/Created: Natural marcasite Country of Origin: Austria