18k Yellow Gold Roberto Coin Amethyst & Diamond Ring Size 6 Weighs 13.7 Grams. Has a small Ruby on the inside of the band, as that is the Roberto coin traditional makers mark. Amethyst stone is 12mm tall x 15mm wide. Ruby & Diamond are both small but nice quality. Be sure to check out our other listings as we offer a wide range of high end designer jewelry. Everything is pre owned & ships usps priority. Thanks for viewing :)