Tanzanite Oval 4.90 Carats Blue Violet Exceptional GemstoneOne 4. 90 carats oval tanzanite, blue violet exceptional (45% 55%) more blue color, VS1 clarity, cut grade excellent, measuring 9 mm wide, 11 mm long, 6. 8 mm deep; with excellent polish and excellent symmetry. The proportions of the tanzanite are as follows: total depth 76%, table width 61%. The overall quality rating of this tanzanite is 970 out of 1000. Tanzanite is color enhanced by heating treating. Customize a Ring or Pendant with This Gemstone?