White, Colorless, Blue, Red, Green, Yellow, Violet
Yellow, Brownish, Reddish, Green, Brownish, Yellow, Green, Yellow, Red
Uneven, Uneven, Gems, Sixth Edition (2006)
Uneven
Al 2O 3Michael OâDonoghue , Gems, Sixth Edition (2006)
(Fe+++,Al)25(PO4)17O6(OH)12•75(H2O)