ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
ZrO 2Arthur Thomas , Gemstones (2009)
CaMoO 4Michael OâDonoghue , Gems, Sixth Edition (2006)