Iluka Unveils 630Mt Heavy Mineral Resource at Goschen South, Boosting Rare Earths Supply

A New Chapter for Iluka’s Rare Earth Ambitions

Iluka Resources Limited (ASX: ILU) has announced a significant milestone with the inaugural Mineral Resource estimate for its Goschen South deposit, situated in the Mallee region of northwestern Victoria. The deposit boasts a combined Indicated and Inferred Mineral Resource of 630 million tonnes grading at 3.7% heavy minerals (HM), translating to approximately 24 million tonnes of HM. This substantial resource underpins Iluka’s strategic vision to bolster its rare earth mineral supply chain.

Geological and Mineralogical Insights

Goschen South is hosted within the Loxton Parilla Sand (LPS) geological unit of the Murray Basin, characterized by a tabular horizon of mineralisation extending over 10.5km north-south and 6km east-west. The mineralisation thickness averages 6.5 metres beneath 13.5 to 25 metres of unmineralised overburden. The deposit’s fine-grained heavy minerals include significant proportions of zircon, ilmenite, rutile, monazite, and xenotime, with rare earth oxides (REO) content averaging 0.88% within the HM fraction.

Notably, the rare earth element profile is dominated by cerium (35.4%), lanthanum (17.0%), neodymium (15.1%), and yttrium (14.0%), elements critical to modern technologies and clean energy applications. These mineral assemblages align closely with Iluka’s nearby Wimmera deposits, reinforcing the region’s potential as a long-life source of strategic minerals.

Robust Exploration and Resource Modelling

The resource estimate is underpinned by 185 Reverse Circulation Air Core drill holes completed between 2012 and 2024, totaling over 7,200 metres and 3,299 sample assays. Iluka employed rigorous sampling, assay, and mineralogical analysis protocols, including QEMSCAN and Laser Ablation ICP-MS, to accurately define the mineral assemblage and rare earth content. The resource classification reflects confidence levels supported by drill spacing, grade continuity, and geological domain consistency, with Indicated resources assigned where drill spacing is approximately 500m by 500m.

Iluka’s use of inverse distance cubed interpolation within Datamine Studio software, combined with comprehensive geological modelling, ensures a reliable representation of the deposit’s grade and tonnage. The company has also excluded environmentally and culturally sensitive areas, such as the Calder Highway corridor and Tyrell Creek, from the resource estimate, demonstrating a balanced approach to resource delineation and stewardship.

Strategic Implications for Rare Earth Refining

The Goschen South deposit’s rare earth mineralisation offers a promising feedstock source for Iluka’s Eneabba rare earth refinery in Western Australia, Australia’s first fully integrated rare earth processing facility. As the global demand for rare earth elements intensifies, driven by clean energy technologies and advanced manufacturing, this deposit could play a pivotal role in securing domestic supply chains and reducing reliance on imports.

While metallurgical challenges remain due to the fine-grained nature of the heavy minerals, ongoing feasibility studies and processing innovations, particularly those being developed at the WIM100 deposit, are expected to inform the optimal extraction and refining pathways for Goschen South.

Looking Ahead

Iluka’s announcement marks a significant step forward in its rare earth strategy, but the path to production will require further drilling, metallurgical testing, and environmental assessments. The company’s ability to navigate these next phases will be critical to unlocking the full value of Goschen South and delivering on its promise as a cornerstone of Australia’s rare earth industry.