Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
Gems, Sixth Edition (2006), Gems, Sixth Edition (2006)
3CaAl 2Si 2O 8 · CaCO 3Anthony et al , Handbook of mineralogy (2001)
SiO 2Michael OâDonoghue , Gems, Sixth Edition (2006)