Item No : 8011660 Gemstone Type : Natural Blue Star Sapphire Approx. Weight (ct) : 1.25 Cts. Shape : Oval Cabochan Size/Dimension : 7.6 x 6.2 MM Depth : 2.5 MM Color : Blue Star 6 Rays Clarity : Opaque Luster : Good Origin : Africa Hardness : 9 Specific Gravity : 3.9 - 4.1 Refractive Index : 1.76 - 1.78 Chemical Composition : Al203 Treatment : Natural