Violet Blue Oval Tanzanite Gemstone 3.18 CaratsOne 3. 18 carats oval tanzanite, violet blue exceptional (15% 85%) color, VS1 clarity, cut grade excellent, measuring 7. 8 mm wide, 9. 3 mm long, 6. 4 mm deep; with excellent polish and excellent symmetry. The proportions of the tanzanite are as follows: total depth 82%, table width 48%. The overall quality rating of this tanzanite is 975 out of 1000. Tanzanite is color enhanced by heating.. Customize a Ring or Pendant with This Gemstone? Did you know