Australian Rare Earths (ASX:AR3) has identified a niobium-rare earth carbonatite mineral system at its Overland Project in South Australia.
The current program has expanded the company’s critical minerals exposure beyond uranium targets.
Drill hole OV167 intersected 19m @ 0.61% total rare earth oxides (TREO) from 86m to end of hole, with the mineralised interval remaining open at depth.
The intersection includes 20% neodymium and praseodymium oxides and 1.70% dysprosium and terbium oxides.
Significant intervals within the broader intersection include 7m @ 0.56% TREO with 0.27% niobium pentoxide from 86m, including 1m @ 1.00% TREO with 0.53% niobium pentoxide from 87m.
The company has identified pyrochlore through petrographic and scanning electron microscope (SEM) assessment of drill cuttings from OV167. Pyrochlore represents the dominant niobium ore mineral globally.
OV167 was drilled above a large coherent magnetic anomaly, interpreted to potentially reflect iron-titanium oxide accumulation within basement rocks.
The company’s current interpretation suggests OV167 may have intersected a sill or dyke-like expression of a larger, untested carbonatite intrusive system nearby.
“OV167 has delivered an exciting and unexpected technical result, the identification of a new niobium-rare earths carbonatite mineral system at Overland,” Managing Director Travis Beinke says.
“Importantly, this is not just a geochemical anomaly. The intersection includes elevated rare earths, niobium, titanium, and iron, together with petrographic and SEM evidence identifying pyrochlore, the principal niobium ore mineral globally.”
Carbonatite mineral systems are globally recognised as major sources of rare earth elements and niobium. The company notes that carbonatite systems typically extend over kilometre scales and may develop shallow supergene-enriched portions.
The discovery was made during Australian Rare Earths’ sedimentary-hosted uranium drilling program at the R254 prospect within the 8,005km2 Overland Project. The program comprised 22 holes for 1,280m aimed at testing two large uranium target zones.
The company plans follow-up work, including expanded geophysical modelling, detailed petrographic and mineralogical assessment, and targeted drilling to test the extent of the carbonatite mineralising system.
Australian Rare Earths cautions that results are from a single drill hole and there is currently insufficient data to define a mineral resource estimate.
Write to JC Villarba at Mining.com.au
Images: Australian Rare Earths
