Uneven, UnevenArthur Thomas, Gemstones (2009)
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001)
Pb 26Ag 10Cu 24Cl 62(OH) 48 · 3H 2OWalter Schumann , Gemstones of the world (2001) More from other references
Ca 2 MgAl 2 BSi 4 O 15 OH Gemdat.org, Management Team (2012)