Colorless, White, Brownish, Reddish, Black, Brownish, Black, Colorless, gray, White, Reddish, Brown
Colorless, White, Yellow, White, Greenish, gray, Brown, Colorless, Yellow
Na 3AlF 6Ulrich Henn and Claudio C.
AlO(OH)Walter Schumann , Gemstones of the world (2001) More from other references