Uneven, UnevenArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Uneven, torn surfaces, (e.g. fractured metals)., Uneven, Gemstones (2009), torn surfaces, (e.g. fractured metals).
(Na,Ca) 8Al 6Si 6O 24(SO 4,S,Cl) 2Ulrich Henn and Claudio C.
FeO(OH)Arthur Thomas , Gemstones (2009)