Gemstone Type : Natural Color Changing Alexandrite Cats Eye Approx. Weight (ct) : 0.45 Ct. Shape: Oval Cabochan Size/Dimension (LxHxW) : 5 x 4 x 2 MM Color : Green With Purple Clarity : Translucent Luster : Good Origin : Srilanka Hardness : 8.5 Specific Gravity : 3.2+ Refractive Index : 1.742 - 1.749 Chemical Composition : BeAl203 Treatment : 100% Natural