Colorless, White, Brownish, Reddish, Black, Brownish, Black, Colorless, gray, White, Reddish, Brown
Green, Blue, Yellow, White
Na 3AlF 6Ulrich Henn and Claudio C.
Mg 3Si 2O 5(OH) 4Anthony et al , Handbook of mineralogy (2001)
Gemmological Tables (2004) More from other references
TranslucentAnthony et al, Handbook of mineralogy (2001)