Name of mineral : Corundum Mohs hardness : 9 Refractive index : 1.762~1.770 Specific Gravity : 4.00 Untreated Gem Quality Size(mm): L 9.3 x W 8.2 x D 5.48 Weight: 3.81 ct US $90,000 宝石辞典もくじ 戻る 次ページ