Brittle, Metallic, Brittle, Metallic
Uneven, Subconchoidal, Uneven, Subconchoidal, Conchoidal, Brittle
Na 2ZrSi 3O 9 · 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)
NaAlSi 2O 6 · H 2OMichael OâDonoghue , Gems, Sixth edition (2006) More from other references