Name of mineral :Corundum Mohs hardness : 9 Refractive index : 1.762~1.770 Specific gravity : 4.00 Weight : 10.25 ct Size (mm) : L 12.0×W 10.0×D 7.60 untreated Gem quality US $40,000 宝石辞典もくじ 戻る 次ページ