Ring for Tanzanite Gemstone 8.37 CaratsPlatinum and diamond engagement ring for previously purchased tanzanite described below. Price includes priority overnight FedEx shipping. Size 6 One 8. 37 carats antique cushion tanzanite, violet blue exceptional (40% 60%) color, FLAWLESS TO VVS clarity, cut grade excellent, measuring 10. 6 mm wide, 11. 9 mm long, 8. 7 mm deep; with excellent polish and excellent symmetry. The proportions of the tanzanite are as follows: total depth 82%, table width