St George Mining Ltd (ASX:SGQ) has uncovered a significant new zone of high-grade niobium mineralisation well outside its existing resource footprint at the Araxá Project in Brazil, strengthening the case for a major expansion of one of the world’s most important niobium and rare earths systems.
The discovery, made around 400 metres northwest of the current mineral resource estimate (MRE), returned thick, high-grade niobium intercepts from surface, led by 81.5 metres at 1.27% Nb₂O₅, including 43 metres at 2.01% Nb₂O₅ and grades peaking at 7.2% Nb₂O₅. The standout result came from discovery hole AXDD031, drilled into an area that had never previously been tested.
St George Mining said the new zone highlights the scale, continuity and open-ended nature of the niobium system at its 100%-owned Araxá Rare Earths and Niobium Project in Minas Gerais, one of the most prolific niobium provinces globally.
Oblique section showing the latest diamond drill holes as well as other significant drilling completed in the current campaign. The latest drill holes with red labels.
Step-out drilling opens new high-grade zone
The latest results are from expansion drilling to the north and west of the existing MRE, part of a broad-spaced step-out program designed to test the limits of mineralisation beyond the known resource. Importantly, the new discovery sits nearly 1.2 kilometres north of the Measured and Indicated component of the MRE, raising the prospect of multiple discrete, high-grade zones that could be developed separately.
According to the company, each drill hole reported from the new area has intersected more than 80 metres of high-grade niobium mineralisation from surface, a characteristic that could have important implications for future mine design and operating costs.
Executive chairman John Prineas said the intersections again underscored the world-class nature of the Araxá system.
“Eighty metres of high-grade niobium from surface is an outstanding result and demonstrates the world-class status of the niobium mineralisation at St George’s Araxá Project,” Prineas said.
“With mineralisation open in all directions, we still have not found the limits of the system,” he added. “Further large step-out drill holes are planned in the area of the new discovery, and we expect to see even more mineralisation uncovered.”
Plan view map of Araxá area showing the location of the diamond drilling relative to the MRE, and the section in Figure 2 above.
Strategic location in Brazil’s niobium heartland
Araxá is located within the Barreiro Carbonatite, widely regarded as the premier niobium district globally and home to the world’s dominant producer, CBMM, whose operations sit immediately adjacent to St George’s tenure.
More than 90% of global niobium supply currently comes from Brazil, with neither the United States nor China having any domestic production. Niobium is classified by the US Department of the Interior as a top-10 critical mineral and ranks second in terms of potential GDP impact if supply were disrupted.
Left: Potential US GDP loss from foreign trade disruptions to mineral commodities. Right: Brazil’s dominance in niobium is highlighted. (Source: Visual Capitalist).
Prineas said the combination of high grades from surface, established infrastructure and a long history of niobium mining in the region created a compelling development proposition.
“The potential commercial advantage of mineralisation starting from surface cannot be underestimated,” he said. “It is a significant point of difference between St George and other niobium developers where mineralisation starts 50 metres or even 100 metres or more from surface.”
Resource upgrade targeted for Q1 2026
Drilling at Araxá is continuing around the clock with three diamond rigs, and St George said 29 drill holes are currently at the laboratory awaiting assays. Follow-up work will focus on infill drilling around the new discovery to support resource conversion, as well as further step-outs to the northwest, where the company believes the potential for continuation of high-grade mineralisation is strong.
Based on drilling completed this month, St George is targeting an updated MRE in the March quarter of 2026, which could incorporate both the new niobium zone and extensions to existing mineralisation.
The maiden MRE, released in April 2025, defined a globally significant resource of 41.2 million tonnes at 0.68% Nb₂O₅ and 40.6 million tonnes at 4.13% total rare earth oxides (TREO).
Rare earths extend into new discovery area
In addition to niobium, the latest drilling has confirmed that high-grade rare earth mineralisation extends into the newly identified zone. Notable intersections include 100.15 metres at 2.16% TREO from surface in hole AXDD025, including 19 metres at 4.17% TREO.
Section showing high-grade Nb2O5 intercepts (cut-off 0.2% Nb2O5) and TREO (cut-off 1% TREO) high grade along with the existing MRE outline, showing the westward expansion of the existing MRE.
St George said the overlap of niobium and rare earths mineralisation reinforces the scale of the multi-commodity system at Araxá and supports the potential for a meaningful resource increase across both metals in the upcoming MRE.
The company acquired 100% of the Araxá Project in February 2025 and has since secured government support aimed at expediting approvals, including participation in Brazil’s MagBras Initiative and a cooperation agreement with the State of Minas Gerais to streamline permitting.