Used as a pigment in paints, coatings, and construction materials due to its stable red-brown color. Commonly found in rust-proof primers and concrete products for color and durability. Employed in polishing agents for glass and metal. Acts as a catalyst in industrial chemical reactions, such as the Haber process for ammonia synthesis. Utilized in magnetic recording media and in the production of certain electronic components. Also used in pharmaceuticals as an additive and in water treatment to remove impurities.