Colorless, Blue, Violet, White, Brown, Colorless, Blue, Violet, White, rose, Brown, gray, Colorless, White, Violet, gray, Colorless, White, Violet, gray
Green, Greenish, Blue, Red
Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Not Available
CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
SiO 2Arthur Thomas , Gemstones (2009)