Almost all of the world's iron ore trade comes down to two minerals: hematite and magnetite. They are both iron oxides, and both end up in a blast furnace or a direct-reduction plant, but they reach it by different routes and are valued in different ways.
The two minerals
| Property | Hematite | Magnetite |
|---|---|---|
| Formula | Fe₂O₃ | Fe₃O₄ |
| Iron in pure mineral | About 70% | About 72% |
| Colour and streak | Steel-grey to red; red-brown streak | Black; black streak |
| Magnetic? | Weakly | Strongly |
| Typical ore grade as mined | Often high; some ore can be used after crushing and screening | Often lower; usually needs concentrating |
Hematite: direct-shipping ore
Rich hematite deposits can produce ore that, after crushing and screening, is ready to sell. This direct-shipping ore is supplied as lumps and fines. Lump ore can be charged straight into blast furnaces or direct-reduction kilns; fines go to sinter plants or are pelletised.
India's iron ore production is largely hematite, from belts in states including Odisha, Jharkhand, Chhattisgarh, Karnataka and Goa. Lower-grade hematite can be beneficiated by washing, gravity separation or flotation.
Magnetite: concentrate and pellets
Magnetite ores are often lower grade as mined, with the iron mineral finely dispersed in rock. Their great advantage is that magnetite is strongly magnetic. The ore is ground fine and passed through magnetic separators, producing a high-grade concentrate.
Because concentrate is a fine powder, it is usually pelletised: rolled into balls and fired. Magnetite actually releases heat as it oxidises during pellet firing, which reduces the fuel needed.
What buyers look at
Beyond the mineral, iron ore is valued on:
- Fe content, the headline grade.
- Silica and alumina, which form slag and increase fuel and flux consumption.
- Phosphorus and sulphur, which harm steel quality.
- LOI, from hydrated minerals such as goethite.
- Size, lumps vs fines, which decides the process route. See iron ore lumps vs fines.
Minequor's iron ore division
Our iron ore division is upcoming. Three iron ore belts are in development in Goa, Odisha and Karnataka, covering hematite and magnetite as lumps and fines, for industrial raw-material demand. Details and updates are on our iron ore page, where you can also register interest.