Mooie Gele Kunziet 13.2x18.8x8.2 mm Ovaal 14.72 CT. Clarity: Eye Clean Hardness: 6.5 - 7 Specific Gravity: 3.2 Refractive Index: 1.66 Chemical Composition: LiAlSi2O6, Lithium Aluminum Silicate Crystal Structure: Monoclinic Treatment: None