Green & Gold Minerals Targets High-Grade Copper Silver Indium at Herberton

Green & Gold Minerals Unearths High-Grade Copper, Silver and Indium at Herberton — Drilling Imminent

Green & Gold Minerals (ASX: GG1) has released a significant exploration update from its Herberton Conductor Metals Project in north Queensland, revealing high-grade copper, silver and indium results from both historic drill records and new reconnaissance sampling. With Green & Gold Minerals Herberton copper silver indium drilling at Copper Hills set to commence in May 2026, the company is moving quickly to test a project that has sat largely unexplored for more than four decades.

What's New and Why It Matters

The announcement delivers on two fronts simultaneously: the public release for the first time of historic drill results from Copper Hills, and new portable XRF sampling data from the mine dumps and adjacent Penang Pekin prospect.

Together, these datasets paint a compelling picture of a multi-metal system rich in copper, silver and indium — three commodities with strong demand tailwinds linked to electrification and AI hardware manufacturing.

Furthermore, the geology team mobilised immediately following EGM shareholder approval of the Herberton acquisition on 17 April 2026, with access road restoration already completed at Copper Hills and underway at Mt Gossan, Siberia and Elizabeth Bluffs.

Historic Drilling: High Grades Confirmed at Depth

The historic drill results from Ocean Resources' 1979–1980 campaign at Copper Hills are being publicly disclosed for the first time following GG1's request to make the original report open file. Eleven percussion holes were drilled across the Copper Hills field, with the best intersections confirming that high-grade copper and silver mineralisation extends below the historically mined oxide zone into fresh rock.

An Important Note on Historic Data

The historic drill results have not been independently validated, and the locations and orientations of some holes are unknown. These results should not be relied upon to estimate the quantity or average grade of mineralisation, and they are unsuitable for use in any future resource estimate. They are reproduced to indicate which metals are present and the potential continuity of mineralisation at depth.

Standout Historic Drill Intercepts from Copper Hills

These intercepts are mostly below the estimated 30m base of weathering, confirming that copper-silver mineralisation persists into unweathered fresh rock — a critical observation for assessing the potential scale of the system.

New XRF Sampling: Indium Emerges as a Key Value Driver

GG1's reconnaissance team collected samples from mine dumps at Copper Hills and Copper Hills West, taking portable XRF readings across 28 sample sites. The results consistently confirmed the presence of copper, silver and indium, with several samples returning exceptional spot readings.

A Note on XRF Analysis

Portable XRF analysis is a spot measurement on selected samples and is intended to identify which metals are present — not to determine the average in-situ grade of mineralisation. These results should not be interpreted as representative of the broader mineralised system.

Selected High-Grade XRF Results from Copper Hills Mine Dumps

The indium readings are particularly noteworthy. Indium was never assayed in the original 1979–1980 drilling programme, meaning its presence in the system is a genuinely new discovery layer that meaningfully adds to the economic potential of the prospect. Indium is on Queensland's critical minerals list and is used in semiconductor manufacturing and display screens.

Penang Pekin: A Second High-Priority Target Emerges

Reconnaissance sampling at Penang Pekin, part of the broader Elizabeth Bluffs mine group, was conducted in April 2026. The area hosts four parallel vein trends within an 80m wide corridor spanning 450m of strike, with three of the four trends hosting historic mine workings.

XRF readings from vein exposures inside historic mine adits returned strong copper, silver and indium values, establishing Penang Pekin as a compelling exploration target in its own right.

Selected XRF Results from Penang Pekin Mine Adits

Historic rock chip sampling at Penang Pekin by Dominion Mining previously returned up to 4.8% Cu, 4.68 g/t Au and 230 g/t Ag, and GG1 has collected additional rock chip samples for laboratory assay, including gold analysis. Results are pending. The broader Elizabeth Bluffs area extends over 4km of strike, and only a portion has been assessed so far.

Mt Gossan–Siberia: A 5km Anomaly Awaiting the Drill Bit

Beyond Copper Hills and Penang Pekin, GG1 has flagged the Mt Gossan–Siberia trend as its highest-priority target for the discovery of a significant deposit. The company has digitised historic soil sample data that defines a near-continuous copper-tin-arsenic-lead anomaly extending over 5km in length and up to 500m in width, with peak copper readings of 4,380 ppm Cu and continuous anomalism above the 100 ppm Cu threshold.

Key Highlights of the Mt Gossan–Siberia Target

• 31 historic shallow drill holes averaging only 30m depth, confirming mineralisation but leaving significant depth potential untested
• Best historic intercept: 8m at 2.58% Cu, 39 g/t Ag and 0.32% Sn
• Only 2 of 31 holes failed to intersect significant mineralisation or lode structures
• Gold and indium were not assayed in historic drilling; rock chip assays from the area have returned up to 1,620 g/t In
• The area has not been explored for 45 years

Access track reinstatement to Mt Gossan–Siberia is scheduled for May 2026, with drilling to follow the completion of work at Chillagoe.

Understanding Indium: The Critical Metal Most Investors Don't Know

What Is Indium?

Indium is a soft, silvery-white metal produced almost entirely as a by-product of zinc refining. It is most widely known as a key input in indium tin oxide (ITO), a transparent conductive coating used in touchscreens, flat panel displays and solar cells. It is also used in semiconductor manufacturing — including AI chips — and in thin-film photovoltaics.

Why Does It Matter for GG1 Investors?

Indium was simply not on the radar during the original exploration campaigns at Copper Hills and Mt Gossan in the late 1970s and 1980s. The complete absence of indium assays from historic drilling means the economic potential of the system has likely been understated.

The Green & Gold Minerals Herberton copper silver indium drilling at Copper Hills programme is now demonstrating that indium is consistently present — sometimes at very high spot readings — across multiple prospects. As a Queensland-listed critical mineral, indium adds a dimension to this project that was invisible to previous explorers.

Key Technical Terms

• XRF (X-ray fluorescence): A portable analytical technique used to identify which elements are present in a sample. It is a screening tool, not a substitute for laboratory assay.
• Gossan: An iron-rich weathered cap formed above a sulphide ore body; often an indicator of mineralisation at depth.
• Malachite / Azurite: Green and blue copper carbonate minerals, respectively; visible indicators of copper mineralisation in the oxide zone.
• Stockwork: A network of small, closely spaced veins — often a sign of a large hydrothermal system.
• Intrusion-related system: A style of mineralisation driven by heat and fluids from an intruding granite body.
• JORC Code: The Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves — the standard for ASX-listed explorers.

Project Context: A Well-Endowed District with Proven Neighbours

The Herberton Mineral Field sits approximately 100km west of Cairns in north Queensland and has a long history of productive mining stretching back to the 1800s. The field is best known for historic tin mining, but it also contains a clearly defined copper-silver dominant zone — the zone in which GG1's tenements sit.

Crucially, the silver-lead-zinc portion of the same mineral field has already delivered results for neighbouring explorers. Companies exploring in the adjacent Ag-Pb-Zn-In zone have defined large, nationally significant silver-lead-zinc-indium resources. GG1's stated strategy is to replicate this exploration success in the copper-silver zone, which it describes as "virtually unexplored in the modern era."

How GG1's Project Compares to the Broader Herberton Setting

What Comes Next: A Clear and Active Drilling Pipeline

GG1 has outlined a structured sequence of activity across its two projects over the coming months.

Herberton Conductor Metals Project — Upcoming Milestones

1. May 2026 — Green & Gold Minerals Herberton copper silver indium drilling at Copper Hills commences
2. May 2026 — Access track reinstated to Mt Gossan–Siberia; fieldwork commences on EPM27229
3. Following Chillagoe drilling — Drilling relocates to Mt Gossan–Siberia to test the 5km anomaly
4. Ongoing — Laboratory assay results pending for rock chip samples from Copper Hills and Penang Pekin, including gold analysis
5. Ongoing — Continued reconnaissance across the broader Elizabeth Bluffs 4km target zone

Chillagoe Gold Project — Concurrent Activity

In addition to Herberton, the Chillagoe Gold Project continues to advance in parallel. Drilling at Sentinel and Mt Wandoo gold targets is planned following the Copper Hills programme. Modelling and mining studies are also continuing at Mt Wandoo, which hosts an inferred JORC resource of 32,400oz Au and 387,000oz Ag at 1.1 g/t Au and 13 g/t Ag.

Investment Thesis: Multiple Catalysts Across a Multi-Metal Platform

GG1 is not a single-asset story. The company is simultaneously advancing a copper-silver-indium-tin project in one of Australia's most historically productive polymetallic districts while progressing a gold resource toward mining studies. Several features of the current setup stand out for investors assessing the opportunity.

1. A Genuinely Underexplored Project in a Proven District

The copper-silver zone of the Herberton Mineral Field has not seen meaningful modern exploration. The last drilling at some key targets was conducted in 1980 — before portable XRF technology, before modern geochemical interpretation tools, and before indium had any commercial relevance.

2. Indium Adds a New Economic Layer to Known Mineralisation

The consistent presence of indium across Copper Hills and Penang Pekin was unknown to prior explorers. With indium listed as a Queensland critical mineral and in demand for AI chips and display screens, every new assay result from laboratory analysis carries the potential to materially upgrade the perceived value of the system.

3. Multiple Prospects Provide Portfolio Diversification Within the Project

Copper Hills, Penang Pekin, Mt Gossan–Siberia and Elizabeth Bluffs all show independent evidence of mineralisation. The 5km soil anomaly at Mt Gossan–Siberia in particular represents an unusually large untested footprint for a target that has already returned encouraging historic drill results.

4. Neighbouring Exploration Success Provides a Credible Blueprint

The large silver-lead-zinc-indium resources defined in the adjacent metal zone of the same mineral field demonstrate that the geological system is capable of hosting significant, economically relevant resources. GG1 is explicitly targeting a similar outcome in the copper-silver zone.

5. Near-Term Drill Results Provide Clear, Imminent News Flow

With drilling commencing at Copper Hills in May 2026 and a sequence of follow-up programmes already planned, investors have a defined pipeline of catalysts ahead. Laboratory assay results for rock chip samples — including gold — are also pending, adding further near-term news flow potential.

"Green & Gold Minerals has assembled a compelling multi-metal project in a historically rich Queensland mineral field that has been largely ignored by modern explorers. With copper, silver and indium confirmed across multiple prospects, drilling imminent at Copper Hills, and a 5km anomaly at Mt Gossan–Siberia waiting in the queue, GG1 offers investors a concentrated series of exploration catalysts in the months ahead. The consistent presence of indium — a metal that previous explorers never tested for — adds a new and potentially significant dimension to what was already a well-credentialled copper-silver system."

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