This is an authentic ROBERTO COIN 18K White Gold Diamond Blue Topaz Mother of Pearl Cocktail Ring 53 6.5. The ring is crafted of 18 karat white gold and features a pear shaped blue topaz and mother of pearl doublet with a halo of diamonds, approximately .23 total carat weight, along with a synthetic ruby on the inside of the band. Follow this item for alerts. Roberto Coin is a registered trademark of Roberto Coin. FASHIONPHILE is not affiliated with Roberto Coin.