Name of mineral :opal Mohs hardness : 5〜6 1/2 Refractive index :1.450 Specific gravity :2.15 Weight :3.53 ct Size (mm) : L 13.1×W 9.8×D 4.80 untreated Gem quality us $9,000 宝石辞典もくじ 戻る 次ページ