ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Uneven, UnevenArthur Thomas, Gemstones (2009)
(Ca,Cr)MgSi 2O 6Gemdat.org , Management Team (2012)
Pb 26Ag 10Cu 24Cl 62(OH) 48 · 3H 2OWalter Schumann , Gemstones of the world (2001) More from other references