TANZANITE, DIAMOND AND EIGHTEEN KARAT GOLD RING. The 18k white gold ring with round, full-cut diamonds and diamond baguettes set around a featured 7.68 cts. oval-cut violetish blue tanzanite. Total combined weight for all diamonds: 1.27 cttw. The ring weighs 9.8 grams and is stamped "18K", "D 1.27" and "TZ 7.68". Ring size: 7.