Uneven, Uneven, Gemstones of the world (2001) More from other references
UnevenAnthony et al, Handbook of mineralogy (2001) More from other references, UnevenAnthony et al, Handbook of mineralogy (2001) More from other references, Brittle, Metallic
H 4Mg 3Si 2O 9Walter Schumann , Gemstones of the world (2001) More from other references
CoAsSAnthony et al , Handbook of mineralogy (2001)