Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Conchoidal, Brittle
Rare tabular and prismatic crystals. Usually occurs as fibrous, parallel veins that break off into cleavage fragments.
None, may show partings on {0001} and {10 1 1}
CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
Fe 2O 3Arthur Thomas , Gemstones (2009)