Brittle, Metallic, Brittle, Metallic, Brittle, Metallic
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Conchoidal, Brittle
Perfect on {010}, indistinct on {100} and {102}
Perfect on {110}, poor on {101}, {001} rare