Blue, White, Grey, Yellow, Green, Colorless, Red, gray
Colorless, Reddish, White, pink, Green, Yellow, Violet, Blue, Brown
Uneven, Conchoidal, Brittle
Uneven, UnevenArthur Thomas, Gemstones (2009)
(Na,Ca)4-8Al6Si6(O,S)24(SO4,Cl)1-2
KCa 4Si 8O 20(F,OH) · 8H 2OUlrich Henn and Claudio C.