Green & Gold Minerals Confirms Two Major Drill Targets at Herberton

Green & Gold Minerals Flags Two Large-Scale Drill Targets as the Herberton Project Takes Shape

Green & Gold Minerals (ASX: GG1) has released a significant exploration update from its Herberton Conductor Metals Project in north Queensland, confirming two substantial copper-silver-tin-indium targets — Mt Gossan and Siberia — are being prepared for drilling. Reconnaissance sampling, including portable XRF rock chip analysis, has returned standout results across both prospects, validating the company's thesis that this underexplored district holds the potential for a large-scale polymetallic resource.

The update arrives ahead of GG1's upcoming drill campaign at Copper Hills-Chillagoe, scheduled to commence in late May 2026, with the drill rig then planned to relocate to Herberton to test the Green & Gold Minerals Herberton drill targets at Mt Gossan and Siberia.

What the XRF Results Are Telling Us

Portable XRF analysis across Mt Gossan and Siberia delivered a suite of high-grade readings across copper, silver, tin, and indium — four metals with strong demand tailwinds tied to electrification and AI infrastructure growth. The headline results from Siberia, taken from historic mine dump samples, were particularly striking:

At Mt Gossan, XRF readings from the mine adit dump and gossanous breccia outcrops returned values of up to 24% copper, 71 g/t silver, and a maximum of 576 g/t indium recorded in breccia outcrop. Bismuth was anomalous across most Siberia samples, with values reaching 1,363 g/t, adding further polymetallic complexity to the system.

Important note for investors: Portable XRF analysis is a spot measurement of individual rock fragments. It is intended to confirm which metals are present and does not represent the average in-situ grade of mineralisation. Conventional rock chip samples have been submitted to a laboratory for verification, with results pending.

Understanding Gossans and Why They Matter

What Is a Gossan?

A gossan is a heavily oxidised, iron-rich surface outcrop that forms when sulphide-bearing ore deposits are exposed to weathering over geological time. As sulphide minerals like chalcopyrite (copper) and pyrite (iron-sulphide) oxidise, they leave behind a distinctive rusty, iron-stained outcrop — the gossan — which acts as a surface indicator of potentially mineralised rock below.

Why Does It Matter to Investors?

Gossans are widely used in mineral exploration as a targeting tool because they signal the presence of a buried sulphide system. The Mt Gossan breccia, with its mapped extent of up to 210 metres long and 125 metres wide, is anomalous in copper, silver, tin, indium, and gold — and critically, it has never been drilled.

The supergene leaching observed at surface (elevated arsenic, lower copper) is consistent with the copper and silver having been concentrated at depth, beneath the oxidised zone, where the higher-grade ore is expected to sit. This pattern is further supported by the higher copper and silver values recorded in underground mine dump samples compared to surface outcrops.

Glossary of Key Terms

• Gossan: Iron-oxide-rich surface outcrop formed by weathering of sulphide mineralisation; a surface indicator of buried ore
• Breccia: Rock composed of angular fragments cemented by a matrix; breccia-style mineralisation can host high-grade ore over substantial widths
• Supergene leaching: Near-surface depletion of soluble metals (e.g. copper) by downward-percolating groundwater, often concentrating metals at depth
• Polymetallic: A deposit or mineralisation containing multiple metals of economic interest
• Indium (In): A rare technology metal used in electronics, solar panels, and display screens; a key by-product of zinc and copper mining
• XRF (X-ray fluorescence): A portable analytical technique used to identify elements in a rock sample; provides indicative rather than definitive grade data
• Pyrrhotite: A magnetic iron sulphide mineral often associated with base metal mineralisation; its presence can be detected by magnetic surveys

Two Targets, Two Compelling Stories

Mt Gossan — A Never-Drilled Breccia System

The Mt Gossan prospect sits within a 5km east-west mineralised corridor (the Siberia lode structure) and is characterised by a large gossanous and quartz stockwork-veined breccia overlying the Siberia Lode. The breccia's mapped dimensions — up to 210 metres long and 125 metres wide — give it meaningful scale potential.

Key characteristics of the Mt Gossan target include:

• The breccia has never been drilled — an unambiguous first-mover opportunity for GG1
• Historic rock chip sampling returned a maximum of 1.97 g/t gold, highlighting gold as a potential additional commodity
• XRF readings from underground mine adit dumps returned up to 24% copper and 71 g/t silver
• The highest indium value recorded in the entire programme — 576 g/t — came from a Mt Gossan breccia outcrop sample
• Historic shallow drilling on the adjacent Siberia Lode (6 holes to a maximum depth of 40 metres) confirmed consistent copper-silver-tin mineralisation but did not test the breccia or any down-dip repeats

Historic drill results on the Siberia lode at Mt Gossan (for context, unverified):

GG1 views these historic intercepts as evidence of consistent grade continuity along the lode, while the breccia itself — sitting directly above — remains an entirely open target.

Siberia — 5km of Strike, High Grades, and a Magnetic Depth Target

Located 1.4 kilometres west of Mt Gossan, the Siberia historic mining area presents a different but equally compelling opportunity. The Siberia Lode outcrops continuously between Mt Gossan and Siberia over a 5km strike length, widening in the Siberia area with the addition of a second, hanging wall lode.

Key characteristics of Siberia include:

• Multiple historic mine adits over an 800-metre strike length, with ore historically transported to the Chillagoe smelter
• XRF analysis of mine dump samples returned grades up to 24.7% copper, 293 g/t silver, 558 g/t indium, 4.2% tin, and 3.7% zinc in individual samples
• Historic drilling returned significant intercepts including 8 metres at 2.6% copper, 39 g/t silver, 0.3% tin from 15 metres (SPH15)
• The lode is open at depth and along strike, with only a limited extent tested by historic shallow drilling
• A magnetic survey has identified east-west striking magnetic high anomalies coinciding with the mapped lode position, interpreted as the down-dip continuation of the Siberia Lode — a magnetic depth target that has never been drill tested

Key historic Siberia drill results (unverified):

Furthermore, the mineralogy transitions from shallow tin-arsenic dominant zones to copper-silver dominant at depth — a pattern consistent with a classic granite-related hydrothermal system where the most valuable base metal mineralisation sits below the weathered horizon.

The Geology That Underpins the Prospectivity

The Green & Gold Minerals Herberton drill targets at Mt Gossan and Siberia are hosted in sandstone units, interpreted to have formed from magmatic hydrothermal fluids associated with the cooling and contraction of the Emuford Granite. Tension fissures created pathways for these fluids, resulting in the polymetallic vein and breccia mineralisation observed today.

The Emuford Granite forms part of the O'Brien's Creek Supersuite, a regionally significant suite of late Carboniferous granites associated with tin, base metal, and gold mineralisation across northern Queensland. This is the same geological setting that has produced multiple significant deposits in the broader Herberton Mineral Field.

Critically, GG1's tenements sit within the copper-silver-tin-indium dominant zone of the Herberton Mineral Field — distinct from the silver-lead-zinc dominant zone to the south, where neighbouring explorers have already defined large, nationally significant resources. The company's stated aim is to replicate that discovery success within its own metal zone.

What's Coming Next

GG1 has a clear and sequenced drilling pipeline in place:

1. Copper Hills drill campaign commences — late May 2026
2. Short drill programme at Chillagoe — following Copper Hills
3. Mt Gossan and Siberia drilling — following Chillagoe programme

In parallel, reconnaissance fieldwork will continue at the Herberton Conductor Metals Project, with additional work planned at the Elizabeth Bluffs trend — a 4km long historic copper mine corridor — and the A1 Line, a 1.3km long prospect.

Work on the Mt Wandoo gold development is also progressing, with modelling and studies ongoing. This forms part of the Chillagoe Gold Project, which holds an inferred JORC resource of 32,400oz gold and 387,000oz silver at 1.1 g/t Au and 13 g/t Ag.

The Investment Thesis in Focus

GG1 is building a case for a district-scale polymetallic discovery in one of Australia's most historically productive mineral fields. Several elements of that case are worth examining together:

The company is pursuing a dual-asset strategy: developing the Wandoo gold resource toward mining studies while systematically exploring the Green & Gold Minerals Herberton drill targets at Mt Gossan and Siberia for a large-tonnage polymetallic resource in the copper-silver-tin-indium zone.

The geological framework is sound. The O'Brien's Creek Supersuite granites have a demonstrated track record of hosting economic mineralisation. The Siberia lode system's 5km of near-continuous surface outcrop, combined with a magnetic depth target that has never been tested and a completely undrilled breccia system at Mt Gossan, represents a genuine exploration opportunity at a scale that is increasingly rare.

Why Investors Should Keep Watch

Green & Gold Minerals has identified two large-scale, drill-ready targets at Mt Gossan and Siberia within the Herberton Conductor Metals Project — one of which has never been drilled — backed by high-grade XRF results across copper, silver, tin, and indium. With a drill programme at Copper Hills commencing late May 2026 and the Green & Gold Minerals Herberton drill targets at Mt Gossan and Siberia to follow, the company is approaching a series of catalysts that could materially define the scale of this opportunity. In a mineral field where neighbouring explorers have already proven the model, GG1 is positioned at an early but rapidly advancing stage of its own discovery story.

The pending laboratory assay results from the rock chip samples submitted for analysis will be the next material data point — providing independent verification of the XRF readings and testing for gold across a broad multi-element suite. Those results, combined with the upcoming drill programme, give investors a clear and near-term set of catalysts to monitor closely.

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