ConchoidalAnthony et al, Handbook of mineralogy (2001), ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Not Available
(Cs,K,Rb)Al 4Be 4(B,Be) 12O 28Anthony et al , Handbook of mineralogy (2001)
SiO 2 (with trace Cr minerals) Gemdat.org , Management Team (2012)