Colorless, White, gray, Brownish, Greenish
Colorless, Green, Black, Brown, Red, Greenish, Yellow, gray
Micaceous, Brittle
Conchoidal, Uneven, Conchoidal, Brittle, ConchoidalArthur Thomas, Gemstones (2009)
KAl 2AlSi 3O 10(OH) 2Walter Schumann , Gemstones of the world (2001) More from other references
Ca 3Fe 2(SiO 4) 3Arthur Thomas , Gemstones (2009)