Brown, Red, Black, Brownish
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
Reddish, Brown, Reddish, Brown
White
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001)
Uneven, UnevenArthur Thomas, Gemstones (2009)
(Zn,Mn2+ ,Fe2+ )(Fe3+ ,Mn3+ ) 2O 4Anthony et al , Handbook of mineralogy (2001)
KCa 4Si 8O 20(F,OH) · 8H 2OUlrich Henn and Claudio C.