ConchoidalAnthony et al, Handbook of mineralogy (2001), ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Sub-Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle
(Cs,K,Rb)Al 4Be 4(B,Be) 12O 28Anthony et al , Handbook of mineralogy (2001)
Cu2H2Si2O5(OH)4