Estrella hits massive manganese oxides in Timor-Leste debut

Estrella Resources has made a landmark discovery in its maiden exploration program in Timor-Leste, intersecting a thick 6.45-metre zone of massive manganese oxides just 1.35m below surface at its Ira Miri prospect.

In what marks the first modern metallic minerals drillhole sunk in the country, Estrella’s initial diamond hole confirmed high-grade manganese mineralisation right from the outset. The mineralisation is still open at 7.8m depth.

The discovery comes hot on the heels of an original outcrop found six months ago and just 3m away. Rock chip samples from the surface discovery returned jaw-dropping assays of up to 58.6 per cent manganese. 

The latest X-ray fluorescence readings from the drill core have now backed up the earlier numbers. They average an impressive 40.1 per cent manganese over the 6.45m interval and confirm more high-grade mineralisation beneath surface.

The drill hole ended early because of intermittent core recovery and a scheduled roster break under Timor-Leste mining laws. Estrella will use the downtime to mobilise a more powerful diamond rig in the next two weeks, capable of punching deeper into the friable manganese-rich zones.

Core has now been removed for a presentation in June at the International Manganese Institute’s conference in Tokyo. 

Notably, a trench dug just 8m southeast of the drill hole also encountered massive manganese oxides starting 0.7m below surface, despite the area showing no visible surface mineralisation. The find suggests the potential for widespread, near-surface mineralisation hidden under shallow cover throughout the area.

Estrella Resources managing director Chris Daws said: “While these are early results from just our first hole and trench in Timor-Leste, the findings are significant. Not only does it provide confirmation that manganese mineralisation extends sub-surface, it also provides further confidence in the accuracy of our developing exploration model which seeks to identify rich manganese deposits.”

Estrella says the rapid turnaround to drilling is a strong sign of the in-country co-operation. Its joint venture partner, state-owned Murak Rai Timor has been instrumental in fast-tracking the campaign. 

Murak Rai Timor’s managing director Jose Goncalves also welcomed the result, calling it a strong endorsement of the joint venture’s strategy and a powerful first step in uncovering Timor-Leste’s critical minerals potential.

The current drilling program is being run by Darwin-based CoreSearch, which also impressively mobilised both diamond and reverse circulation drill rigs into Timor-Leste’s remote Lautém district in record time.

Since Timor-Leste is still an underexplored region, Estrella says it holds a substantial first mover advantage, which could crack open a treasure trove of untapped targets and turn the region into something special.

Estrella is also eyeing the country’s broader mineral potential, with a significant high-grade limestone deposit sitting directly above its manganese horizon. 

Two weeks ago, the company struck a major deal to export up to 500 million tonnes of premium, coral-rich limestone over five years to meet booming industrial demand in South East Asia. 

The limestone, part of the Baucau Formation, is high-purity calcite with minimal impurities, making it ideal for cement, glass, agriculture and nickel processing. It also sits straight above the manganese targets, allowing for streamlined dual resource exploration.

A major 20,000m drilling blitz is now on the cards, combining 10,000m of reverse circulation drilling and 3000m of deeper diamond drilling in the first phase, followed by a further 10,000m of reverse circulation drilling after a geological review.

With Timor-Leste aiming to make its mark in the global supply chain for industrial metals, Estrella’s Ira Miri manganese find could be the opening salvo of something much bigger. 

Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au