Brittle, Metallic, Brittle, Metallic
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
{110} Perfect, {010} Perfect
Perfect on [10 1 1] three directions with angle of 74° 55
Na 2ZrSi 3O 9 · 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)
CaCO 3Ulrich Henn and Claudio C.