Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
ConchoidalAnthony et al, Handbook of mineralogy (2001), ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
CaBe 2(PO 4) 2Michael OâDonoghue , Gems, Sixth Edition (2006)