Colorless, White, Brownish, Reddish, Black, Brownish, Black, Colorless, gray, White, Reddish, Brown
Brownish, Red, Yellow, White, Brown, orange
Uneven
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle
Na 3AlF 6Ulrich Henn and Claudio C.
Pb 5(AsO 4) 3ClMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references