Conchoidal, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Mg 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006)
Ca 3Fe 2(SiO 4) 3Arthur Thomas , Gemstones (2009)