This is an authentic ROBERTO COIN 18K Yellow Gold Diamond Palazzo Ducale Stud Earrings. The earrings are crafted of 18 karat yellow gold and feature square studs with a brushed finish, set with round brilliant cut diamonds weighing approximately .09 total carat weight. The earrings also feature the signature synthetic ruby stone on the back of each earring. Follow this item for alerts. Roberto Coin is a registered trademark of Roberto Coin. FASHIONPHILE is not affiliated with Roberto Coin.