3.15One 3. 15 carats round brilliant cut tanzanite, blue violet vivid color, 10X LOUPE CLEAN clarity, cut grade excellent, measuring 8. 7 mm wide, 8. 7 mm long, 6. 1 mm deep; with very good polish and very good symmetry. The proportions of the tanzanite are as follows: total depth 70%, table width 50. 5%. Tanzanites are color enhanced by heating. The overall quality rating of this tanzanite is 935 out of 1000.