My periodic table poster is now available! Magnetite. Description from the source: Magnetite (Fe+2 Fe+32 O4 cub.), Potosi, Bolivia. Perfect crystals on matrix. 6x5x2,5 cm; 65 g. Source: Simone Citon Contributor: John Gray Acquired: 27 December, 2008 Text Updated: 28 December, 2008 Price: Trade Size: 2.4" Composition: Fe2O4