White, Blue, Yellow, Brown, Green, Brownish, Greenish, gray
Colorless, Yellow, Brown, Green, Colorless, Green, Yellow, Red, Reddish, Brown
Gemstones (2009), Flexible Flexible fragments.
Brittle, Metallic, Brittle, Metallic
Al 2Si 4O 10(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Ca(Mg,Al)3(Al3Si)O10(OH)2