Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Conchoidal, Brittle
Brittle, Metallic, Brittle, Metallic
Fe 2O 3Arthur Thomas , Gemstones (2009)
CaZnSiO 4 · H 2OAnthony et al , Handbook of mineralogy (2001)