Estrella unearths more high-grade manganese zones in Timor-Leste

Estrella Resources has rolled out another set of manganese-rich results from its Ira Miri project in Timor-Leste, with several high-grade intervals hinting at the potential for multiple stacked manganese horizons.

The company says it has also wrapped up drilling at its adjacent Werumata limestone project, revealing thick carbonate layers and a fresh limestone unit at depth with promising early commerciality indications. 

Estrella says the latest assays from Ira Miri have built on the company’s previous ultra-high-grade hits, delivering peak intercepts of 5.2m at 39.6 per cent manganese, including a bonanza 2.5m section running at 54 per cent manganese. Another hit returned 6.2m at 45.3 per cent manganese. 

Earlier ultra-high-grade intercepts included 6.5m at 51.7 per cent manganese and 8.1m at 53 per cent, with peaks of up to 58 per cent manganese in follow-up drilling.

The results mark the final batch of a 45-hole program at the project, totalling 1533m of diamond drilling. Management says 16 of the holes intercepted notable manganese mineralisation within the target Noni Formation host rock. 

The company says the mineralisation shows consistent traits in pockets, with strong manganese grades alongside very low phosphorus and iron impurities, suggesting a straightforward beneficiation process for the supergene-enriched material.

Notably, new geological modelling points to the possibility of stacked or fault-shifted manganese horizons, hinting at substantial extension potential both deeper and along strike. 

Meanwhile, at Estrella’s Werumata limestone prospect, the company has completed a combined reverse circulation (RC) and diamond drilling effort spanning 3717m across 42 holes, targeting a large and potentially high-purity limestone resource. Some estimates have pegged an exploration target in the 500-million-tonne range, suggesting its limestones could supply Timor for many decades to come. 

Drilling intercepted limestone widths up to 87m thick at its Baucau prospect, as well as chalk units up to 38m thick at Batu Putih. Combined units reached 112m in thickness, with an average of 57m across the project.

Estrella says the key find at Werumata was an underlying weathered marl layer – a mix of carbonate and clay – that could be valuable for acid neutralisation, similar to limestone and may be folded into future resource calculations. 

Assays for the limestone samples are in the pipeline, with results due in the new year.

Estrella Resources managing director Chris Daws said: “The consistency of high-grade manganese intersected at Ira Miri continues to underline the quality and potential scale of this system, particularly given its favourable metallurgical characteristics. In parallel, the company has completed drilling at Werumata and identified a potentially economic marl unit materially enhances the strategic value of the limestone project.”

The manganese mineralisation across a number of outcrops on Estrella’s extensive Timor-Leste land holding has been well documented. The company says its setup mirrors established high-silica, low-iron manganese operations globally, where the metal plays a core role in steel production for added strength.

On the limestone side, Werumata's thick, clean horizons could be used to target markets for cement feedstock, agricultural lime and industrial acid adjustment. As an added bonus, the overlying carbonate frequently caps manganese mineralisation below, providing a handy overlap that could streamline operations.

With assays imminent and follow-up work primed for early 2026, Estrella's dual focus in Timor-Leste continues to build steam. While the limestone might anchor steady output, the revelation of potentially stacked manganese horizons could potentially add serious upside and scale.

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