Uneven, Subconchoidal, Uneven, Subconchoidal, Conchoidal, Brittle
Conchoidal, Brittle, Conchoidal, Brittle, Conchoidal, Brittle
NaAlSi 2O 6 · H 2OMichael OâDonoghue , Gems, Sixth edition (2006) More from other references
(Mg,Fe2+ ) 2(Mg,Fe2+ ) 5Si 8O 22(OH) 2Anthony et al , Handbook of mineralogy (2001)