White, Colorless, Blue, Red, Green, Yellow, Violet
Colorless, Green, Black, Brown, Red, Greenish, Yellow, gray
Not Available
Conchoidal, Uneven, Conchoidal, Brittle, ConchoidalArthur Thomas, Gemstones (2009)
SiO 2Ulrich Henn and Claudio C.
Ca 3Fe 2(SiO 4) 3Arthur Thomas , Gemstones (2009)