Blue Violet 2.94 Square Cushion Tanzanite GemstoneOne 2. 94 carats square cushion tanzanite, blue violet exceptional color, 10X LOUPE CLEAN clarity, cut grade excellent, measuring 7. 9 mm wide, 7. 9 mm long, 6 mm deep; with very good polish and excellent symmetry. The proportions of the tanzanite are as follows: total depth 75. 9%, table width 58%. The overall quality rating of this stone is 940 out of 1000. Tanzanites are color enhanced by heating.