Manufacturing & Uses of Iron Oxide Iron Oxide: There is a natural Iron Oxide and Synthetic Iron Oxide from the steel mill. When they produce the cold steel rolling plate in steel mill, they wash the plate by hydrochloric acid to remove the impurities. We produce Iron Oxide by extracting (Fe₂O₃) from the used Acid. Uses of Iron Oxide: EG’s Iron Oxide is mainly used for industrial material of soft and hard ferrite and basic material of pigments according to its color and impurities concentration.