Conchoidal, Splintery, Fibrous, UnevenArthur Thomas, Gemstones (2009)
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
CaSO 4 -2(H 2O)Arthur Thomas , Gemstones (2009)
CaMoO 4Michael OâDonoghue , Gems, Sixth Edition (2006)