Uneven, UnevenArthur Thomas, Gemstones (2009)
Uneven, Uneven, Gems, Sixth Edition (2006)
Pb 26Ag 10Cu 24Cl 62(OH) 48 · 3H 2OWalter Schumann , Gemstones of the world (2001) More from other references
Al 2O 3Michael OâDonoghue , Gems, Sixth Edition (2006)