Australian Rare Earths Uncovers 10km Magnetic Corridor Expanding Niobium-REE Targets at Overland, South Australia

Reprocessed 1999 Magnetic Survey Reveals Extensive 10km Carbonatite Corridor at Overland

Australian Rare Earths Limited has announced a major expansion of its exploration targets at the Overland Project in South Australia through reprocessing a high-resolution airborne magnetic survey from 1999 with 80-metre line spacing. This detailed geophysical analysis delineated a prominent 10-kilometre north-south magnetic anomaly, indicating a compelling zone for carbonatite-related mineralisation. This discovery significantly enlarges AR3's drill target inventory beyond the initial OV167 discovery announced on 8 July 2026, positioning the company with multiple exploration opportunities along the newly identified corridor.

The 10km magnetic anomaly identification follows AR3's earlier confirmation of niobium-rare earth mineralisation at OV167, which recorded a notable intercept of 19 metres at 0.61% TREO from 86 metres to the hole’s end. The magnetic reprocessing now offers a broader geological framework suggesting this mineralisation may be part of a larger, more extensive carbonatite system. The company highlights that the confirmed mineralisation at OV167, combined with the scale of the magnetic feature, lays the groundwork for systematic exploration along the entire corridor.

Historic Drill Hole R64 Indicates Potential Carbonatite System Extension Beyond OV167

A review of historic drill hole R64, located within the same 10-kilometre magnetic corridor about 3 kilometres south of OV167, revealed an independently supported exploration target. This hole recorded a significant gamma response from 56 metres to 71 metres, with mineralisation remaining open at depth. This gamma signature is comparable to that recorded at the R254 target, tested by AR3 during the OV167 drilling program. The presence of this response in R64 within the broad magnetic zone suggests the carbonatite system could extend considerably beyond the initial discovery.

The gamma response in R64 provides an early indication that mineralisation may continue along strike within the magnetic corridor. R64 was drilled vertically to 71 metres with a 120-millimetre diameter hole, adding valuable historical data for interpretation. While further drilling is needed to confirm mineralisation at R64, the combination of historic gamma response, magnetic anomaly, and confirmed mineralisation at OV167 creates multiple independently justified drill targets along the corridor.

OV167 Niobium and Rare Earth Mineralisation Confirms Carbonatite System Potential

The OV167 intercept, detailed in the company’s announcement on 8 July 2026, provides foundational evidence for the carbonatite system at Overland. The significant intercept of 19 metres at 0.61% TREO from 86 metres to end of hole includes elevated neodymium-praseodymium (NdPr), dysprosium-terbium (DyTb), and niobium oxide (Nb8O5). Mineralisation remains open at depth, indicating further drilling could uncover additional mineralised zones. This intercept confirms that the Overland Project hosts a viable niobium-rare earth mineralised system comparable to global carbonatite deposits.

The OV167 mineralisation composition aligns with known carbonatite system characteristics, globally recognized as major rare earth and niobium sources. Elevated NdPr and DyTb are especially significant due to their high demand in technology sectors. AR3 emphasizes that OV167’s mineralisation provides geological, geochemical, and mineralogical support for continued systematic exploration of the broader R254 target and the wider 10-kilometre magnetic corridor.

Global Carbonatite Analogues Highlight Multi-Commodity Potential for AR3

The update cites several significant global and regional carbonatite systems illustrating the mineral potential of these geological settings. Lynas’ Mt Weld operation and major niobium mines worldwide exemplify the rare earth and niobium production capacity of carbonatite systems at commercial scale. The historic Phalaborwa carbonatite complex in South Africa, a major copper producer with by-product rare earths, zirconium, and other metals, further demonstrates carbonatites’ multi-commodity potential.

Closer to Australia, recent carbonatite discoveries by WA1 Resources at West Arunta and Encounter Resources have shown elevated copper mineralisation alongside niobium and rare earth elements. These regional analogues suggest AR3 could unlock multi-commodity upside at Overland as exploration progresses beyond the confirmed niobium-REE mineralisation at OV167. The upcoming drilling program aims to assess both the niobium-rare earth system’s extent and the broader critical minerals potential of the carbonatite complex.

Statistical Success Rates Support Continued Investment in Carbonatite Exploration

AR3 provided industry context on carbonatite discovery success rates, referencing Woolley and Kjarsgaard (2008). Their data shows only about one in ten mineral exploration projects reach drilling, and only one in 1,000 drill programs discovers a viable deposit. Specifically, approximately 6% of 527 reported carbonatites and alkaline-carbonatite complexes host active mines, 3% have historic mines, and 11% contain established mineral resources. This suggests newly found carbonatite systems have roughly a 9% chance of hosting a mine, a meaningful success rate in exploration.

Against this backdrop, AR3 has advanced Overland from a geophysical target to confirmed niobium-rare earth mineralisation at OV167, surpassing typical early-stage hurdles. The upcoming drilling campaign aims to determine if OV167’s success can be replicated along the 10-kilometre corridor, providing multiple chances to establish whether the discovery is isolated or part of a larger mineralised system. These statistics imply that if the discovery extends along the corridor, it could significantly enhance AR3’s critical minerals portfolio.

Targeted Drilling Program to Assess Corridor Continuity and Expand Mineralisation

AR3 plans a focused drilling program to test priority magnetic geophysical targets along the 10-kilometre north-south magnetic corridor. Results will clarify how much of the corridor beyond OV167 contains mineralisation. The program’s objectives include extending and better defining the OV167 carbonatite system, investigating the magnetic anomaly near historic hole R64, and assessing the system’s scale and continuity along strike. These aims seek to establish the discovery’s overall size and significance. Drilling will prioritize anomalies identified from magnetic reprocessing, targeting locations likely to yield mineralisation comparable to or extending OV167.

This systematic drilling approach evaluates the broader carbonatite system beyond the initial find. By targeting both OV167 extensions and the independently supported R64 site, the program offers multiple avenues to confirm system continuity and scale. AR3 stresses that confirming mineralisation at additional corridor sites will be key to gauging Overland’s overall significance. The program also includes detailed assaying, petrography, and downhole geophysics to support ongoing geological interpretation and target generation across the project.

Regulatory Approvals and Land Access Pending Before Drilling

Prior to starting drilling, AR3 must secure regulatory approvals and land access to conduct operations along the magnetic corridor. These standard prerequisites for Australian mineral exploration must be completed before mobilizing drilling equipment. The company identifies obtaining these approvals and agreements as the immediate next step. Compliance with South Australian exploration and environmental regulations is mandatory for the Overland Project.

After approvals and access are secured, AR3 plans to execute exploration drilling along the corridor, followed by detailed assaying, petrography, and downhole geophysics. The company also intends to continue geophysical interpretation and target generation across the broader project area, potentially identifying further drill targets beyond the initial 10-kilometre corridor. This phased approach enables progressive refinement of the carbonatite system understanding and prioritization of drill locations.

Overland Discovery Enhances AR3’s Portfolio Alongside Koppamurra Rare Earths Project

AR3 positions the Overland Project discovery as a valuable addition to its critical minerals assets while maintaining focus on advancing the Koppamurra rare earths project. The company states, "Overland continues to add meaningful critical minerals upside to AR3's portfolio, while our priority remains firmly on advancing the Koppamurra rare earths project toward commercialisation." This indicates that although Overland is a significant exploration opportunity, near-term development efforts and resources remain concentrated on Koppamurra.

This dual strategy allows AR3 to pursue a near-term project at Koppamurra while exploring longer-term potential at Overland, maintaining optionality within its critical minerals portfolio. The early-stage Overland discovery offers upside potential as capital and management focus remains on the more advanced Koppamurra project. This balanced approach positions AR3 to benefit from Koppamurra’s commercialisation while building confidence in Overland through systematic exploration of the 10-kilometre magnetic corridor.

Early-Stage Status Highlights Exploration Risks and Data Gaps

AR3 issues a caution regarding the early-stage nature of the Overland discovery, emphasizing that results come from a single OV167 drill hole and currently lack sufficient data to define a Mineral Resource under Australian standards. The company notes uncertainty whether further exploration will yield a Mineral Resource estimate and that single intercept results may not represent the entire target area. This caution acknowledges that while OV167 and magnetic data are encouraging, substantial additional work is needed to confirm commercial viability or resource potential.

AR3 indicates that OV167’s geological, geochemical, and mineralogical characteristics support further exploration but provides no guidance on the likelihood of discovering additional significant mineralisation or resource size. The limited dataset and early-stage status mean material exploration risk remains. The upcoming drilling program aims to address data gaps by testing additional corridor locations, but exploration outcomes remain uncertain.