Brittle, Metallic, Brittle, Metallic
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
Na 2ZrSi 3O 9 · 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)
Mg 3(SiO 4)(F,OH) 2Anthony et al , Handbook of Mineralogy (2001)