Uneven, Uneven, Gems, Sixth Edition (2006), Uneven, Conchoidal
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Perfect on {001}, very good on {010}, imperfect on {110}
Distinct on {100} and {110}
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
3NaAlSi 3O 8 · NaClAnthony et al , Handbook of mineralogy (2001)