ConchoidalWalter Schumann, Gemstones of the world (2001), ConchoidalWalter Schumann, Gemstones of the world (2001)
Conchoidal, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle
CaTiSiO 5Ulrich Henn and Claudio C.
PbCu(SO 4)(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006)