Uneven, Conchoidal, UnevenWalter Schumann, Gemstones of the world (2001)
Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Perfect {010}, imperfect {100}
Rare tabular and prismatic crystals. Usually occurs as fibrous, parallel veins that break off into cleavage fragments.