Conchoidal, Metallic, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Uneven, Brittle, Metallic, Brittle, Metallic, Brittle, Metallic
Fair in four directions forming octahedrons
Good on {110}, (110) ^ (1 1 0) ≈87°; parting on {100}
Cu 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
(Na,Fe,Ca)Si 2O 6Ulrich Henn and Claudio C.