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Iron(II,III) oxide nanopowder - is the chemical compound with formula Fe3O4. It occurs in nature as the mineral magnetite.
IO 0003 - Iron(II,III) oxide nanopowder, APS 20 nm, 99.5% - used as a pigment in magnetic applications, polishing compounds, cosmetics, medicines, polymers, rubber, fillers, building, construction, appliances and magnetic inks.