Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
SrCO 3Walter Schumann , Gemstones of the world (2001) More from other references
CaCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references