ConchoidalWalter Schumann, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Metallic
Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Perfect on {010}, good on {100}
Rare tabular and prismatic crystals. Usually occurs as fibrous, parallel veins that break off into cleavage fragments.
Be 2BO 3(OH)Ulrich Henn and Claudio C.
CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references