Rare earth elements

Prospectivity

The Territory’s most significant rare earth deposit, Arafura Rare Earths Ltd’s Nolans project, is located in the Aileron Province north of Alice Springs. The deposit is hosted within fluorapatite veins containing allanite and monazite, and is rich in the magnet-feed rare earths neodymium and praseodymium (NdPr).

Arafura Rare Earths Ltd’s Nolans project is globally significant with the potential to meet around 4% of the world’s global supply of NdPr. The company has all approvals in place for mining through to onsite separation of rare earths to produce 4,440 tpa of NdPr oxide and 470 tpa of a mixed middle-heavy rare earth (SEG/HRE) oxide (REO). They also plan to produce 144,000 tpa of fertilizer-grade phosphoric acid (54% P₂O₅). Enabling construction works were completed in 2023. Binding offtake agreements in place with Hyundai, Kia and Siemens Gamesa for up to 2,020 tpa NdPr oxide. Most recent announcements include securing debt debt funding of more than US$1 billion and signing gas supply agreements.

Carbonatite-related REE mineralisation

Carbonatite-related REE mineralisation occurs in carbonatite rocks or associated alkaline intrusions emplaced along craton margins. The Territory is prospective for carbonatite related REE mineralisation associated with the margin of the North Australia Craton in the Aileron and Irindina provinces of Central Australia. The Territory’s most significant REE deposit, Arafura Rare Earths Ltd’s Nolans project, is located in the Aileron Province north of Alice Springs, and although not carbonatite-hosted, is interpreted to be carbonatite related. The deposit is hosted within fluorapatite veins containing allanite and monazite, rich in the magnet-feed LREE neodymium and praseodymium (NdPr).

Recent discoveries of carbonatite-hosted niobium and rare earth mineralisation in the western Aileron Province in Western Australia highlight the potential of the region for further carbonatite-hosted discoveries. Norwest Minerals Ltd, Trek Metals Ltd, Encounter Resources Ltd and WA1 Resources Ltd have exploration licence applications in the Northern Territory for this mineralisation style. Other companies exploring for carbonatite-related rare earths in central Australia include MetalsGrove Mining Ltd, Babalus Resources Ltd, Megawatt Metals Corp, First Development Resources PLC and Askari Metals Ltd.

Unconformity-related REE mineralisation

There is emerging potential for unconformity-related heavy REE mineralisation across the Territory. This style of mineralisation is known to occur in the Tanami Region, where the Browns Range deposits immediately across the border of Western Australia contain 10.8 Mt @ 0.76% TREO. Mineralisation occurs as xenotime hosted in hydrothermal breccia- or quartz veins. Northern Minerals Ltd’s Boulder Ridge prospect within the NT contains outcropping xenotime-bearing veins, with a maiden drill program planned at the prospect. Other unconformities with potential to have associated heavy REE mineralization include the base of the greater McArthur Basin, and the basal Amadeus Basin unconformity. Other explorers for this style include Heavy Rare Earths Ltd.

Placer-type REE mineralisation

The Territory also has potential for accumulations of monazite and xenotime in heavy mineral sands and alluvial sediments. Enova Mining Ltd’s Charley Creek HREE alluvial deposit has a large resource of detrital xenotime and monazite within alluvial fans in central Australia. Coastal heavy mineral sands deposits occur on the Tiwi Islands north of Darwin.

Clay-hosted REE mineralisation

Exploration for clay-hosted REE deposits is increasing in the Territory. Xenotime-hosted HREE rich clays at the Skyfall and Stromberg prospects west of Pine Creek highlights potential for clay-hosted HREE mineralisation in the northern NT. Transition Minerals Ltd have discovered a clay-hosted LREE deposit rich in NdPr in the northern Barkly region at the Vanadis prospect, associated with an overlying vanadium-rich horizon. Grades of up to 0.48% TREO were discovered in a maiden drilling campaign supported by the NT Government’s Geophysics and Drilling Collaborations program in 2022–23. Other companies exploring for clay-hosted rare earths include Green Critical Minerals Ltd, Energy Metals Ltd, URO Corp Ltd, and GSW Resources Pty Ltd.

Phosphorite-hosted REE mineralisation

Phosphorite-hosted REE occur in sedimentary phosphate rocks enriched by global seawater REE at the time of deposition. The Georgina Basin in the Northern Territory has large sedimentary phosphorite deposits with potential to host rare earths. Recent work at Avenira Ltd’s Wonarah phosphate deposit in the Georgina Basin has identified significantly anomalous REE mineralisation (up to 0.21% TREO) in a number of stratigraphic horizons within the deposit.

Other REE mineralisation styles

In addition to the mineralisation styles described above, the Aileron and Irindina provinces in central Australia may have potential for hydrothermal- and intrusion-related mineralisation styles. A rare earth-gold-uranium system in the Pine Creek Orogen at the Quantum prospect south of Darwin highlights the potential for rare earths associated with hydrothermal gold and uranium systems in the northern NT.

Download the rare earth elements opportunities factsheet PDF (4.2 MB).

Projects

More information