White, Colorless, Blue, Red, Green, Yellow, Violet
Greenish, White, White, gray, Greenish, Reddish, White, gray, Greenish, Green, gray, White, gray, Greenish, Green, gray
Conchoidal, Conchoidal, Gemstones of the world (2001)
Uneven, Uneven, Gems, Sixth Edition (2006), Uneven, Conchoidal
SiO 2 · nH 2OWalter Schumann , Gemstones of the world (2001)
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)