Uneven, Subconchoidal, Uneven, Subconchoidal, Conchoidal, Brittle
Uneven, Uneven, Gemstones of the world (2001) More from other references
NaAlSi 2O 6 · H 2OMichael OâDonoghue , Gems, Sixth edition (2006) More from other references
H 4Mg 3Si 2O 9Walter Schumann , Gemstones of the world (2001) More from other references