Colorless, White, Brownish, Reddish, Black, Brownish, Black, Colorless, gray, White, Reddish, Brown
Colorless, Green, Yellow, White, Colorless, Green, Yellow, White
Uneven
Conchoidal, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
Na 3AlF 6Ulrich Henn and Claudio C.
Mg 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006)