Encounter Resources (ASX: ENR) has confirmed the potential of the latest West Arunta niobium discovery with high-grade assay results from the Green prospect at its Aileron project in Western Australia.

Located in a remote area of east-central WA, the West Arunta region has become a global hotspot for the hunt for niobium over the last 12 months, with Encounter the latest to taste success there.

Early assays from a reverse circulation (RC) drilling campaign at Green have established the prospect hosts extensive, enriched, high-grade niobium mineralisation in the upper portion of its system.

Reconnaissance drilling

The promising results received so far are from a large reconnaissance aircore drilling campaign Encounter completed at Green earlier in 2024.

That program mapped a large, laterally mineralised zone containing frequent high-grade niobium intercepts over 2% niobium pentoxide (Nb₂O₅), often ending in mineralisation.

Highlight results include 10m at 4.2% Nb₂O₅ from 57m – as part of a 38m section containing 1.5% Nb₂O₅ from 51m – and 10m at 4.3% Nb₂O₅ from 51m, as part of 16m at 3.0% Nb₂O₅ from 47m to the end of the hole.

Carbonatite complex

Executive chair Will Robinson said it was then decided to undertake RC drilling to delineate coherent, high-grade zones with mineable dimensions within the large, mineralised carbonatite complex at Green.

“The first RC holes completed at the western side of Green demonstrate some of the best, depth-extensive niobium mineralisation in the West Arunta,” Mr Robinson said.

“A further 30 RC drill holes have been completed at Green through the better mineralised zones defined by aircore drilling, and we look forward to providing further assay results in the months ahead.”

The company has also commenced metallurgical test work on selected drill core.

Mineralogical scanning and initial sighter beneficiation and flotation tests are expected to be wrapped up in the first half of 2025.

Critical mineral

Niobium is one of a suite of commodities identified by the Australian government as critical minerals—those considered vital for the well-being of the world’s economies whose supply may be at risk of disruption.

According to Mordor Intelligence, the niobium market size is currently estimated at 106.85 kilotons and is expected to grow at a CAGR of 9.92% to reach 171.49kt by 2029.

Over the medium term, accelerating usage of structural steel and increasing demand for lighter-weight and more fuel-efficient vehicles are some of the factors driving market growth.