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