UnevenAnthony et al, Handbook of mineralogy (2001) More from other references, UnevenAnthony et al, Handbook of mineralogy (2001) More from other references, Brittle, Metallic
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
{100} Good, {010} Good, {001} Good
{110} Perfect, {110} Perfect
CoAsSAnthony et al , Handbook of mineralogy (2001)
(Fe,Mn) 7Si 7O 21Ulrich Henn and Claudio C.