Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal
Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Metallic
Ca(Li 2Al)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012)
CuSMichael OâDonoghue , Gems, Sixth edition (2006) More from other references