Yellow, Red, Reddish, Brown, Colorless, White, Yellow, Red, Reddish, Brown, Colorless, White, gray, White, gray, Reddish, White, gray, Reddish, White, gray, Reddish
Blue, Greenish
KAl3(SO4)2(OH)6
(Fe2+ ,Mg)Al 2(PO 4) 2(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006)