Uneven, Subconchoidal, Uneven, Subconchoidal, Splintery, UnevenArthur Thomas, Gemstones (2009)
Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Good on {110}, poor on {100}
Rare tabular and prismatic crystals. Usually occurs as fibrous, parallel veins that break off into cleavage fragments.
Al 2SiO 5Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references