ConchoidalWalter Schumann, Gemstones of the world (2001), ConchoidalWalter Schumann, Gemstones of the world (2001)
ConchoidalAnthony et al, Handbook of mineralogy (2001), ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Al 2Be 3Si 6O 18Martin H.
Al 4(Ta,Nb) 3(O,OH,F) 14Ulrich Henn and Claudio C.