UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
Uneven, Conchoidal, Brittle, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
Ca 2(Mg,Al) 6(Si,Al,B) 6O 20Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Na(Li 1.5Al 1.5)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012) More from other references