Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle, Metallic
Uneven, Uneven, Management Team (2012), Conchoidal, Brittle
Mg 2Si 2O 6Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Fe 3O 4Ulrich Henn and Claudio C.