Estate 8.63 carat oval tanzanite platinum ring. This estate platinum ring features an oval tanzanite at 8.63 carats. The tanzanite is accented with 1.83 carat total weight of round brilliant diamonds. These diamonds have SI2-SI3 clarity and H color. The estate tanzanite platinum ring weighs 13.40 grams, is appraised at $13,760, and is a size 6.5.