possible iocg systems, page-3

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Iron oxide copper gold ore deposits (IOCG) are important and highly valuable concentrations of copper, gold and uranium ores hosted within iron oxide dominant gangue assemblages which share a common genetic origin.

These ore bodies range from around 10 million tonnes of contained ore, to 4,000 million tonnes or more, and have a grade of between 0.2% to 5% copper, with gold contents ranging from 0.1 to 3+ grams per tonne (parts per million). These ore bodies tend to express as cone-like, blanket-like breccia sheets within granitic margins, ore as long ribbon-like breccia or massive iron oxide deposits within faults or shears.

The tremendous size, relatively simple metallurgy and relatively high grade of IOCG deposits can produce extremely profitable mines.

Iron oxide copper-gold deposits are also often associated with other valuable trace elements such as uranium, bismuth and rare earth metals, although these accessories are typically subordinate to copper and gold in economic terms.

Famous examples include the Olympic Dam, South Australia and La Candelaria, Chile deposits.