Conchoidal, Conchoidal, Gemstones of the world (2001) More from other references, Conchoidal, Brittle
Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
111 (perfect in four directions)
Rare tabular and prismatic crystals. Usually occurs as fibrous, parallel veins that break off into cleavage fragments.