Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
(Zn,Mn2+ )OMichael OâDonoghue , Gems, Sixth Edition (2006)
SrCO 3Walter Schumann , Gemstones of the world (2001) More from other references