Uneven, Conchoidal, Brittle, Metallic, ConchoidalArthur Thomas, Gemstones (2009)
Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009)
Ca 3Cr 2(SiO 4) 3Ulrich Henn and Claudio C.
(Mg,Fe2+ )Al 2O 4Gemdat.org , Management Team (2012) More from other references