The Northern Territory contains a number of iron ore deposits, with two periods of mining from 1967-1974 and 2007-2014 producing a total of 18.2 million tonnes of iron ore. Most production has occurred from the Frances Creek iron ore deposits near Pine Creek, which are hydrothermally-enriched hematite deposits within the Pine Creek Orogen.
The Frances Creek mine, 200 km southeast of Darwin, produced 1.5-2 Mtpa of iron ore from 2007 to 2014 and moved into care and maintenance in late 2014. The iron mineralisation occurs in a fault breccia in the lower Wildman Siltstone and ranges in composition from haematite to goethite and limonite. There are over 50 named occurrences and prospects covering a distance of approximately 35 km. Resources and reserves at Frances Creek announced in 2010 included total Probable Reserves of 5.8 Mt at 57.9% Fe and Indicated and Inferred Resources of 9.9 Mt at 58.1% Fe.
Relatively large resources also occur in the the Roper iron field, which is hosted in the Roper Group of the McArthur Basin, south of the Roper River. The Roper iron field contains more than 1 billion tonnes of moderate grade iron ore, with around 85 million tonnes of higher grade direct shipping ore (57-59% Fe) at the Roper River and Roper Bar deposits. Mining occurred at Roper Bar in 2013-2014, with export through Bing Bong port. Iron ore in the Roper field varies from massive to oolitic and pisolitic haematite, and occurs within interbedded medium- to very coarse-grained ferruginous sandstone and siltstone of the Mesoproterozoic Sherwin Ironstone Member.
Iron resources also occur as part of TNG Ltd’s Mount Peake vanadium-titanium-iron project in the Arunta Region, where feasibility studies propose the production of pig iron from a future mining operation.
Historical mining of gold- and copper-bearing ironstone at Tennant Creek has produced tailings containing up to 70% magnetite at a number of sites that are located near the Alice Springs-Darwin railway line and existing infrastructure.