Encounter (ENR) Drills 70,000m at Aileron Niobium Project in WA

Encounter Resources (ASX: ENR) has two aircore rigs running at its Aileron project in Western Australia’s West Arunta region. The company is working through a planned 70,000-metre drilling program for 2026 that combines infill drilling and regional exploration.

One rig is completing infill work across potential high-grade starter pit areas at Green. A second aircore rig is testing priority regional targets across the broader tenure. A third multi-purpose diamond and mud-rotary rig is scheduled for mobilisation in the September quarter. That rig will support geotechnical, hydrogeological, and metallurgical drilling for pre-development studies.

The drilling follows a major resource upgrade. In April, Encounter increased the combined inferred mineral resource estimate by 54% to 120 million tonnes at 0.77% niobium pentoxide above a 0.25% cut-off. That includes a high-grade component of 26 million tonnes at 1.7% Nb2O5 above a 1.0% cut-off. The upgrade came after a single season of drilling following the maiden resource in May 2025.

Metallurgical work at Green has shown strong recoveries at high concentrate grades across multiple composites representing sections of the anticipated starter pits. The results support the company’s plan to upgrade the inferred resource to indicated status through the current 30,000m of infill drilling.

The environmental and permitting work is also advancing. Encounter has lodged a mining lease application over the area proposed for mining, processing, and infrastructure. The application area was selected to accommodate potential modifications for operational, engineering, environmental, or cultural heritage requirements as survey work advances. The conceptual site layout includes processing infrastructure, tailings storage, return water ponds, evaporation ponds, stockpiles, an airstrip, camp facilities, a solar farm, and access roads.

Executive chair Will Robinson said the work program had maintained strong momentum.

“In recent months Encounter has increased its resource base by more than 50%, demonstrated strong metallurgical results at Green, and executed a partnership agreement to help foster expansion of the growing niobium oxide industry,” Robinson said.

Robinson said Encounter was also advancing permitting and stakeholder engagement.

“An initial baseline study identified the optimal location for processing infrastructure and a Mining Lease has been applied for over this area.”

“We continue to have positive engagement with multiple government bodies and Traditional Owner groups around the advancement of Aileron and the West Arunta region.”

The regional aircore program is designed to test a series of high-priority niobium-REE and copper-gold targets across Encounter’s tenure. The company is using rapid, cost-effective aircore drilling to assess further discovery opportunities. The 40,000m of regional drilling is underway alongside the resource-definition work at Green.

For a project at this stage, the critical test for the stock price over the next 6–12 months is whether the infill drilling at Green converts inferred tonnes to indicated status at grades that match the high-grade component. The metallurgical results are encouraging – recoveries above 70% at concentrate grades over 60% Nb2O5 on multiple composites – but the sample set covers only a portion of the starter pits. A second test is the extent of new discoveries from the regional program. Any significant copper-gold or niobium-REE intercepts from the aircore drilling would expand the project’s optionality well beyond the current Green resource.

The mining lease application is a procedural milestone that signals the company is serious about development, not just exploration. The timeline to a mining lease in Western Australia depends on the referral process under the Environmental Protection Act and native title agreements. The engagement with Traditional Owner groups and government bodies Robinson noted will be a factor in the pace of approvals.

For the broader niobium market, Aileron is positioned as a potential new source outside Brazil, which currently supplies about 90% of global niobium. The resource grade of 0.77% Nb2O5 is comparable to existing operations, and the high-grade component at 1.7% is well above average. If Encounter can demonstrate a feasible development path, the project could alter the supply dynamics for specialty steel and alloy markets that depend on niobium as a hardening agent.

The next concrete date to track is the September quarter mobilisation of the diamond rig. The results from the infill drilling at Green, which are expected to be released in batches over the coming months, will determine whether the indicated resource target is achievable within the 2026 drilling budget.