Ferric oxide, also known as iron(III) oxide, is an inorganic compound with the chemical formula Fe₂O₃. It occurs naturally as the mineral hematite and is one of the most important iron ores used in steelmaking. This reddish-brown compound is well known for its use as a pigment, an abrasive, and a raw material in various industrial processes. Ferric oxide is widely distributed in nature, found in rocks, soils, and rusted metal surfaces, as it forms readily when iron reacts with oxygen in the presence of moisture.

One of the most common applications of ferric oxide is as a pigment. Due to its strong coloring power and stability, it is used in paints, coatings, ceramics, plastics, and construction materials. Known as “red iron oxide” in the pigment industry, Fe₂O₃ provides a durable, non-fading color that resists weathering and UV exposure. Its natural and synthetic forms are both used, with synthetic ferric oxide offering more consistent particle size and purity for industrial applications.

In metallurgy, ferric oxide plays a critical role as a source of iron. Hematite ore is processed in blast furnaces to produce molten iron, which is then refined into steel. This makes Fe₂O₃ an essential raw material for the construction, automotive, and manufacturing industries. It is also used in thermite reactions—where it reacts with aluminum to produce molten iron and aluminum oxide—a process employed in welding and metal cutting.

Ferric oxide’s abrasive qualities make it valuable in polishing and grinding applications. In its finely powdered form, known as “jeweler’s rouge,” it is used to polish precious metals, glass lenses, and gemstones to achieve a smooth, high-gloss finish. Its hardness and fine particle structure allow it to remove microscopic surface imperfections without damaging the underlying material.