ConchoidalWalter Schumann, Gemstones of the world (2001), ConchoidalWalter Schumann, Gemstones of the world (2001)
Conchoidal, Conchoidal, Gemstones of the world (2001) More from other references, Fibrous
SiO 2Ulrich Henn and Claudio C.
CaAl 2(Fe3+ ,Al)Si 3O 12(OH)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references