Conchoidal, Brittle, Conchoidal, Brittle, Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Uneven, Uneven, Gems, Sixth Edition (2006), Uneven, Conchoidal
[001] good, [210] distinct
Perfect on {001}, very good on {010}, imperfect on {110}
PbSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)