Gemstone Type : Natural Tourmaline Carving Approx. Weight (ct) : 4.65 Ct. Shape: Carving Fancy Size/Dimension (LxHxW) : 17 x 10 x 3 MM Color : Green Clarity : Translucent Luster : Outstanding Origin : Africa Hardness : 7.5 Specific Gravity : 3.0+ Refractive Index : 1.62 - 1.68 Chemical Composition : Na(Li,al)3al6si6o18(Bo3)3 (oh)4