ConchoidalWalter Schumann, Gemstones of the world (2001), ConchoidalWalter Schumann, Gemstones of the world (2001)
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Conchoidal, Brittle
CaTiSiO 5Ulrich Henn and Claudio C.
Zn 4Si 2O 7(OH) 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references