Uneven, Subconchoidal, Uneven, Subconchoidal, Conchoidal, Brittle
Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
NaAlSi 2O 6 · H 2OMichael OâDonoghue , Gems, Sixth edition (2006) More from other references
CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references