Chrysoberyl Approx Weight: 0.45 CT. Size: 7x3.5 mm Shape: Marquise Facet Color: Vibrant Fine Lemon Green Clarity: Clean Luster: Stunning Origin: Africa Hardness: 8.5 Specific Gravity: 3.7+ Refractive Index: 1.75 Chemical Composition: BeAl2O4, Beryllium Aluminum Oxide Crystal Structure: Orthorhombic Treatment: None