Item #: 770699 Year: 1998 This is an authentic CARTIER 18K White Gold Black Onyx Tank Ring size 53 or 6.5. The ring is crafted of 18 karat white gold and features a square black onyx stone set along a high polished band. Follow this item for alerts. Cartier is a registered trademark of Cartier. FASHIONPHILE is not affiliated with Cartier.