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) Tough, UnevenArthur Thomas, Gemstones (2009) Tough, Brittle, Uneven
CoAsSAnthony et al , Handbook of mineralogy (2001)
Mn 8Si 6O 15(OH,Cl) 10Ulrich Henn and Claudio C.