Historically, hematite was the preferred iron ore due to its direct usability in blast furnaces (BF) for steel production, without beneficiation (value improvement) costs. But with declining hematite ore quality and a shift towards low-carbon technologies such as DRI, the demand for high-quality magnetite ore is at historically high levels.

This demand is driven by magnetite’s low impurities, enabling even higher steel grades, and its lower energy requirements, which reduce end-to-end process emissions due to higher iron concentration, which also reduces waste by-products. Magnetite is increasingly recognised as a critical resource in the green steel process.

Magnetite offers several benefits over hematite for steel decarbonisation, making it an increasingly attractive option for high-quality iron ore:

Higher iron content

Magnetite boasts a higher iron content by weight (70-72.4% Fe) than hematite (60-68% Fe), resulting in greater efficiency and cost effectiveness, as less magnetite is needed to produce the same amount of iron.

Lower impurities

Magnetite typically contains fewer impurities, such as phosphorus, sulphur and gangue (silica and alumina), than hematite. This results in cleaner steel production and reduced emissions, making it ideal for DRI and EAF processes. The reduced amount of gangue also limits the fluxes required during steelmaking and the amount of slag generated.

Lower energy requirement

Magnetite processing involves wet grinding, as opposed to hematite’s dry grinding, which produces finer particles and so improves the efficiency of the beneficiation process. The magnetic separation process used with magnetite is also more energy-efficient than gravity separation or flotation, which are employed in hematite processing, and doesn’t require the additional chemicals needed for hematite.