Item No : 345797 Gemstone Type : Natural Unheated White Topaz Approx. Weight (ct) : 4.50 Ct. Shape : Cushion Cut Size/Dimension : 10 x 10 MM Color : White Clarity : Transparent Luster : Good Origin : Africa Hardness : 8 Specific Gravity : 3.4 - 3.5+ Refractive Index : 1.61 -1.64 Chemical Composition : Al2(OH,F)2Si04 Treatment : Natural