ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Gems, Conchoidal, Brittle
MgAlBO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Ca 3Ti4+2(Fe3+2Si)O 12Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references