Estrella Resources Uncovers High-Grade Copper and Nickel at Laleno Dome

Estrella Resources Uncovers High-Grade Copper, Nickel, Silver and Manganese Across a Virtually Untouched Frontier

Estrella Resources (ASX: ESR) has reported high-grade copper, nickel, silver and manganese discoveries from its Timor-Leste concessions, with rock-chip results including up to 60.34% Cu, 182 ppm Ag, 0.75% Ni and manganese samples averaging 51.7% Mn. The results come from two prospects, Sica and the newly defined Daudere, which lie on the flanks of the Laleno Dome — a geological structure described by the company as nearly 700 metres high and about 10 kilometres wide.

The update matters because it broadens Estrella's Timor-Leste story beyond manganese and points to a possible multi-commodity hydrothermal system. Preliminary work suggests the copper mineralisation at both prospects may be linked, with the Laleno Dome emerging as the key regional target for follow-up mapping and geophysics.

"At nearly 700m in height and ~10km in width, the Laleno Dome dominates the landscape. Fortunately for Estrella, it sits in the middle of our Timorese land concessions portfolio. This is the first time the company has systematically mapped the structure to determine its significance." — Robert Mencel, Managing Director

Two Discoveries Begin to Define the Laleno Dome Story

Estrella described Sica and Daudere as separate discoveries made during mapping and sampling of the Laleno Dome. The two areas are approximately 5 kilometres apart, yet the company's geological interpretation suggests they may reflect the same broader mineralising process.

That interpretation is important for investors because early-stage exploration becomes more meaningful when different prospects start to fit a coherent geological model. Rather than isolated rock-chip anomalies, Estrella is now outlining a larger target area with potential structural and intrusive controls.

Sica Prospect Returns Very High-Grade Copper and Silver

At Sica, on the northern flank of the dome, Estrella reported two styles of copper-bearing material within close proximity. One was oxidised copper mineralisation in weathered rocks of the Noni Formation, while the other was a specimen of oxidised massive sulphide located about 150 metres southwest.

The key Sica assays reported were:

According to the company, ESR006093 came from small malachite and azurite nodules exposed in a weathered rock face, while ESR006094 was collected from iron-rich weathered material known as gossan. A gossan is oxidised rock formed when sulphide minerals weather near the surface, and it can act as an indicator that mineralisation may exist below.

The standout result was ESR006095, which assayed 60.34% Cu and 182 ppm Ag. Whilst rock-chip samples are selective by nature and do not indicate mineable widths, such grades can still be highly relevant because they show that strong mineralising fluids were active in the area.

Daudere Adds Manganese and Another Copper Occurrence

At Daudere, around 5 kilometres southwest of Sica, the company identified a new prospective area during continued mapping. The first area inspected contained numerous manganese oxide boulders, whilst a separate copper occurrence was later sampled about 300 metres to the west.

The manganese results were striking for their consistency:

Estrella said the uniformly high manganese grades and very low impurity levels suggest the samples represent high-purity primary manganese oxides upgraded by supergene enrichment. In simple terms, supergene enrichment is a near-surface weathering process that can concentrate metals by dissolving and then re-depositing them.

Furthermore, the company said this supports the view that the boulders are likely close to their source rather than having been transported far from where they formed.

Daudere also produced a copper result from fine-grained sandstone containing malachite — ESR006286 returned 12.4% Cu and 77 ppm Ag — collected from residual lag on outcrop in the Noni Formation, adding a second copper occurrence on the dome's flank.

Why the Laleno Dome Matters

A central feature of the announcement is not just the grades, but the company's interpretation that the discoveries may be linked by the Laleno Dome itself.

In geological terms, a dome is an upward-arched rock structure. Domes can matter in mineral exploration because they may focus fractures, intrusive activity and fluid flow. When hot, metal-bearing fluids move through those pathways and cool, they can deposit minerals in veins, sulphides or altered host rocks.

How Do Hydrothermal Mineral Systems Form?

A hydrothermal system forms when heated fluids move through cracks and porous rocks underground, carrying dissolved metals such as copper, silver, gold, zinc or nickel. As pressure and temperature change, or as the fluids react with surrounding rocks, the metals can drop out of solution and form mineral deposits.

Several geological features can improve the chance of this happening:

• Intrusions: bodies of magma that cool underground and can act as heat and metal sources
• Faults and fractures: pathways that allow fluids to move
• Reactive host rocks: rocks that chemically interact with the fluids
• Structural traps: places where fluids slow down or spread out, allowing minerals to precipitate

In Estrella's case, the report outlined multiple signs that such a system may be present around the Laleno Dome, including several intrusions — mostly ultramafic, plus gabbro plugs and intermediate dykes — widespread hydrothermal alteration, quartz-calcite vein fragments with crustiform textures, and Q-XRD mineral analysis identifying arsenide minerals such as enargite and lautite in sample ESR006095.

For non-specialist readers, epithermal refers to shallow mineral deposits formed from hot fluids, often associated with volcanic or intrusive environments. Estrella said the Q-XRD results point more towards a high-sulphidation epithermal or porphyry-related setting than a volcanogenic massive sulphide style.

Q-XRD Adds Weight to the Geological Interpretation

One of the more technical but important parts of the update was the Quantitative X-ray Diffraction (Q-XRD) analysis completed on the Sica copper discoveries. Q-XRD is a lab method used to identify the actual minerals present in a sample, rather than just measuring bulk chemistry.

That distinction matters because different mineral species can point to different deposit types and exploration models. In the report, Estrella said ESR006095 contains arsenide minerals including enargite and lautite, consistent with its elevated arsenic content of 10.7% As.

The company stated these minerals are typically associated with high-sulphidation epithermal and porphyry copper systems rather than volcanogenic massive sulphide deposits. That does not confirm a deposit model at this stage, but it helps narrow the range of possibilities and gives the exploration team a more targeted framework for upcoming geophysical work.

The Investment Case Now Extends Beyond Manganese

Before this update, Estrella's Timor-Leste exposure was largely framed around manganese. However, the latest announcement expands that picture into a broader multi-commodity exploration story. Key commodities identified so far include:

The tungsten result should be read carefully. Estrella specifically noted that the 213 ppm W sample came from material that had been pre-concentrated by sieving and panning, and that this process exaggerates the anomalism. Even so, it adds to the broader picture of a geologically varied system.

For investors, the importance lies less in any single sample and more in the pattern now emerging. Multiple commodities, two prospects, a consistent host formation, intrusive activity, alteration and structural scale together increase the range of possible exploration outcomes.

Near-Term Catalysts From Geophysics and Commercial Activity

The next phase of work appears focused on testing what sits beneath clay-rich surface cover around the dome and at known prospects. Estrella said preliminary Magneto Telluric drone (MTd) results from Ira Miri were encouraging enough to justify further expenditure on 3D inversion processing.

Resistivity/Induced Polarisation (Res/IP) surveys are expected to begin at Ira Miri in mid-July 2026, followed by surveys at Leuro and Sica. The near-term programme outlined in the announcement includes:

Alongside exploration, the company said the sale of a trial manganese parcel is progressing, with nine separate parties having expressed interest in purchasing all or part of the parcel. Management said discussions are nearing completion and a sale recommendation is expected to be provided to the board shortly.

"The question now is: just how special is the Laleno Dome? The planned regional geophysical survey will help answer that." — Robert Mencel, Managing Director

Why Investors May Be Watching Closely

This ASX update positions Estrella as an early-stage explorer with a widening commodity footprint in a region the company describes as virtually unexplored by modern standards. Historical work in the area is described as limited and non-systematic, meaning the current programme represents genuine first-pass discovery potential.

Several factors are likely to keep investor attention on the story:

1. Very high-grade rock-chip copper results, even allowing for the selective nature of such sampling
2. Geological consistency across separate prospects, which may support a district-scale model
3. A large, internally held structural target in the Laleno Dome
4. Upcoming geophysical surveys, which could help test concealed targets beneath cover
5. Commercial interest in manganese, which may provide near-term validation of product demand

The current stage remains early. No drilling results were reported in this announcement, and the company's interpretations will need further validation through geophysics, additional mapping and eventually drilling if warranted.

In addition, the immediate question for the market is no longer limited to manganese potential. It is whether the Laleno Dome could host a broader hydrothermal mineral system capable of generating multiple target styles across copper, silver, nickel and manganese. The next round of geophysical results is likely to be central to that assessment.

Want to Identify the Next Major Multi-Commodity Discovery Before the Market Does?

Discovery Alert's proprietary Discovery IQ model scans ASX announcements in real time, instantly alerting subscribers to high-potential exploration stories like Estrella Resources — turning complex geological data across 30+ commodities into clear, actionable insights. Explore how historic mineral discoveries have generated extraordinary returns on Discovery Alert's dedicated discoveries page, and begin your 14-day free trial today to position yourself ahead of the broader market.