Uneven, Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Even
UnevenAnthony et al, Handbook of mineralogy (2001) More from other references, UnevenAnthony et al, Handbook of mineralogy (2001) More from other references, Brittle, Metallic
Perfect {010} imperfect {100}
{100} Good, {010} Good, {001} Good