Violet, Blue, Red, Yellow, Brown, gray
Colorless, Reddish, White, pink, Green, Yellow, Violet, White, pink, Green, Yellow, Violet, White, Colorless, Blue, Green, Brown, Yellow, pink, Violet, White, pink, Green, Yellow, Violet
Uneven, Uneven, Gems, Difficult, Fibrous
Uneven, UnevenArthur Thomas, Gemstones (2009)
Al 2O 3Arthur Thomas , Gemstones (2009)
KCa 4Si 8O 20(F,OH) · 8H 2OUlrich Henn and Claudio C.