Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle, Metallic
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Mg 2Si 2O 6Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Na 2Ca 2(CO 3) 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references