The Nolans Bore deposit is located at the southern end of the Reynolds Range in the central Aileron Province of the Arunta Region. The Aileron Province comprises greenschist to granulite facies metamorphic rocks with protolith ages in the range 1865-1710 Ma.

Supracrustal rocks in the Reynolds Range are divided into 2 broad units: the Lander Rock Beds (LRB) and the Reynolds Range Group. The LRB comprise (meta)turbiditic rocks that range in metamorphic grade from greenschist to granulite. In the Nolans region, the LRB include schist, phyllite, andalusite hornfels, garnet-cordierite-biotite-quartz granofels, sillimanite-biotite-cordierite-orthoclase granofels, tourmaline metaquartzite, and tourmaline-quartz pods.

Granite intrusion occurred in the Reynolds Range area between 1810 and 1790 Ma. Granitic rocks which intrude the LRB in the vicinity of Nolans are a southern extension of the Mount Boothby Orthogneiss (MBO). The supracrustal rocks and granites were overprinted by high grade metamorphism to amphibolite and granulite facies during 1590-1560 Ma.

Nolans Bore is a geologically unique deposit, which has world-class characteristics in size and grade of rare earth elements (REE), phosphate, uranium and thorium.

Apatite-hosted REE-P-U(-Th-F) mineralisation at Nolans Bore is distributed over an area of approximately 150 hectares within a kilometre radius of the bore. Mineralisation occurs predominantly in a series of sub-parallel tabular bands (vein- or dyke-swarm) of massive fluorapatite (Ca₅(PO₄)₃(F,OH)). The bands dip steeply (65°-90°) to the NNW, are up to 25 metres thick, and extend laterally and at depth over tens to several hundreds of metres. They are hosted primarily by gneissic granite assigned to the MBO.

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A simplistic three-fold subdivision of rock types is apparent in the North Zone Resource at Nolans Bore:

• Footwall granitic gneiss (to the south), which includes fluorapatite bands and stockwork mineralised granitic gneiss
• Main mineralised zone, comprising footwall fluorapatite bands, a central mylonite stockwork zone, and hangingwall fluorapatite
• Hangingwall gneiss (to the north), which includes fluorapatite bands.

The bulk (65-70%) of the REE-U content in the fluorapatite rock is hosted by minor amounts (up to 7-8%) of the phosphate-deficient REE mineral cheralite ([LREE, Ca][P, Si]O₄). Only about 30-35% of the REE-U is hosted in the crystal lattice of the fluorapatite. Other identified REE-U-Th mineral species identified include bastnaesite, monazite, thorite and allanite.

Work undertaken by Arafura Resources at Nolans since 2000 includes:

• 9 costeans totalling 1,223 metres
• 381 RC and core drill holes totalling 38,038 metres.