Uneven, Conchoidal, Brittle, Metallic, ConchoidalArthur Thomas, Gemstones (2009)
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Ca 3Cr 2(SiO 4) 3Ulrich Henn and Claudio C.
Cu 3(OH) 2(CO 3) 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references