Magnetite
Karara comprises a large-scale, long-life magnetite orebody amenable to bulk mining and processing.
Magnetite ore has lower iron content (34-36% Fe) than hematite ore (58-64% Fe). It must be upgraded by a complex ore treatment process (beneficiation) to produce a high-grade (+65% Fe) concentrate for steelmaking.
Its magnetic properties enable magnetite to be refined to a premium concentrate product that is globally accepted and highly sought after as to produce high quality, low impurity steel.
The treatment and beneficiation of magnetite ore requires crushing, screening, high-pressure grinding, magnetic separation, filtering and drying to produce a premium, high iron grade concentrate with very low impurities.
Further processing by Karara’s customers involves the agglomeration and thermal treatment of concentrate to produce pellets, which can be used directly in either a blast furnace or direct reduction steelmaking plant.
The additional “up-front” and higher costs involved with the extra processing required to produce magnetite concentrate is offset by the significant price premiums that high grade, high-quality concentrate commands from steel mills, compared to conventional (hematite) benchmark iron ore products.
Hematite
The early development of Karara was supported through the exploitation of small-scale satellite deposits of hematite iron ore. Australia’s iron ore industry is historically based on the mining, production and export of high-grade hematite iron ore. Hematite ore makes up the bulk of Australia’s iron ore production and of the global seaborne trade in iron ore. High-grade hematite which can be shipped directly to customers after simple processing (crushing, screening, sorting and blending) is often referred to as ‘Direct Shipping Ore’ or DSO.
The satellite hematite orebodies at Karara that were known to be economic have been mined and are now exhausted.