Name of mineral : Tourmaline Mohs hardness : 7~7 Refractive index : 1.624~1.644 Specific Gravity : 3.06 Heated Gem Quality Size(mm): L 18.1 x W 16.7 x D 10.91 Weight: 27.83 ct US $40,000 宝石辞典もくじ 戻る 次ページ