Australian Gold and Copper Achilles Deepest Drill Hole Returns Strongest Result

Australian Gold and Copper Drills Deepest Achilles Hole and Returns Strongest Result From Depth-Extension Program

Australian Gold and Copper Ltd (ASX: AGC) has reported the strongest assay from its recent depth-extension drilling at the Achilles deposit in New South Wales, with the deepest hole completed at the project intersecting high-grade silver-gold-base metal mineralisation well below the current Mineral Resource Estimate (MRE). Hole A3DD014 returned 26m at 102g/t AgEq from 433m, including 15m at 153g/t AgEq and 2m at 770g/t AgEq, extending mineralisation to at least 540m down dip from surface.

The result matters because the current Achilles MRE extends to about 250m down dip, meaning the new intercept sits roughly 250m below the base of the existing resource model. In practical terms, the drilling program has now shown that the northern high-grade zone continues substantially deeper than the current resource boundary, supporting the case for future underground resource growth.

The Key Drilling Result at Achilles

The latest ASX update covered the final two holes from AGC's completed depth-extension program, designed to test whether the Achilles system continued below previously reported high-grade mineralisation. The standout intercept came from A3DD014, the deepest hole drilled at Achilles so far.

A second hole, A3DD016, also returned mineralisation.

According to the announcement, A3DD014 was drilled about 60m below and east of the first two deep step-out holes reported on 7 July 2026, adding both depth and lateral confidence to the geological model.

"A3DD014 is the deepest hole drilled at Achilles to date and has returned the strongest result from the recent depth-extension drilling program. This is an excellent result and confirms the Achilles mineral system remains open and fertile hundreds of metres below the current resource," said Glen Diemar, Managing Director.

Why the Depth Extension Matters to Investors

The importance of this result becomes clearer when set against the dimensions of the existing resource. The December 2025 Achilles MRE covers mineralisation from surface to around 250m down dip. The latest drilling has now confirmed mineralisation to at least 540m down dip, adding around 290m of tested dip extent below the current resource envelope.

That does not automatically mean all of that additional depth will convert into future resources. However, according to the company, the completed program confirms the system remains open at depth and provides geological support for assessing future underground mining potential, resource growth, and longer-term development options.

This latest program also builds on earlier deep drilling. The step-out holes were drilled beneath A3RCD089, previously the deepest hole in the northern high-grade zone, which had returned 11m at 424g/t AgEq from 305m, including 3m at 1,453g/t AgEq, as reported by AGC on 27 January 2026.

How the Progression Stacks Up

The sequence outlined in the ASX material is straightforward:

1. Earlier drilling established the current resource down to about 250m down dip
2. Holes A3DD013 and A3DD015 extended mineralisation beyond 400m down dip
3. A3DD014 has now extended that confirmation to at least 540m down dip

For investors, that sequence points to a deposit that may still be growing vertically as well as laterally. Furthermore, management has been clear about the longer-term implications.

"These deeper results are important for long-term planning. They provide further confidence as we assess future underground mining potential, resource growth and development options for the deposit," Diemar said.

Achilles Resource Base Provides the Starting Point

The current Achilles MRE, reported on 16 December 2025, already provides AGC with a defined precious and base metals resource. The new drilling sits outside that estimate, which means the latest intersections are currently upside rather than included inventory.

Achilles MRE Summary

Two points stand out from the resource table. First, 58% of the resource is in the Indicated category, which generally reflects a higher level of geological confidence than Inferred material. Second, the underground component already totals 9.9Moz AgEq when combining Indicated and Inferred underground categories, giving some context for why deeper extensions matter.

The ASX release also broke the resource down by material type.

In addition, AGC stated that 23 recent drill holes were not included in the initial MRE because of assay timing. The company has previously highlighted one of these as 6m at 2,474g/t AgEq in A3RCD086. This suggests any future resource update may reflect not only the latest deep drilling but also a backlog of strong historical results not yet captured in the model.

Understanding AgEq and Why It Matters

Achilles is not a single-metal deposit. It contains silver, gold, zinc and lead, with some copper also reported in assays. Because multiple metals contribute to the potential value of each interval, AGC reports many results as silver equivalent, or AgEq.

What Is AgEq?

AgEq converts the value contribution of gold, zinc and lead into an equivalent silver grade using assumed metal prices and expected metallurgical recoveries. This gives investors a single number that can be used to compare drill results more easily across a polymetallic deposit. For the drill results in this release, the company used the following formula:

AgEq (g/t) = Ag (g/t) + 92.6 × Au (g/t) + 32.1 × Zn (%) + 21.8 × Pb (%)

The assumptions disclosed in the ASX announcement were:

• US$31.6/oz silver
• US$2,700/oz gold
• US$2,850/t zinc
• US$2,000/t lead
• Metallurgical recoveries of 83% silver, 90% gold, 95% zinc and 92% lead

Copper was not included in the AgEq calculation because AGC stated it was not recovered in metallurgical testing.

Why Should Investors Pay Attention to AgEq?

AgEq is useful because it helps compare wide, mixed-metal intersections using a common value measure. A result such as 2m at 770g/t AgEq does not mean the rock contains only silver at that grade. It means the combined contribution of silver, gold, zinc and lead adds up to the equivalent value of 770 grams of silver per tonne under the company's stated assumptions.

That makes AgEq a practical screening tool, but it is not a substitute for looking at the underlying metal mix. At Achilles, the precious metal component comes from silver and gold, while zinc and lead can add meaningful value depending on recoveries and future processing outcomes.

What the Forward Program Looks Like

With the deep drilling program now complete, AGC said the next phase at Achilles is expected to focus on shallow RC drilling targeting oxide gold-silver mineralisation near surface. RC, or Reverse Circulation, is a lower-cost drilling method commonly used for shallower targets and resource definition work.

According to management, this next program is intended to be:

• Lower cost
• Faster to drill
• More directly aligned with near-surface resource growth

A key target is expected to include follow-up on A3OX010, which previously intersected 5m at 19.1g/t Au, 52g/t Ag and 1.3% Pb+Zn from 30m, within a broader 42m at 266g/t AgEq from 26m. Approvals for this drilling are reported to be underway.

Outside Achilles, the company also outlined activity across its broader South Cobar portfolio.

The Evergreen program is particularly relevant because AGC said it is targeting an initial MRE at the Browns Reef-Evergreen precious and base metals deposit. That gives the company a second potential resource growth avenue beyond Achilles.

The Broader Investment Picture for AGC

The latest Achilles result does not stand alone. It sits within a broader investment case built around resource growth, portfolio development, and a relatively clean balance sheet. Three factors are likely to remain central for investors following AGC.

1. Achilles Continues to Show Growth Potential

The current resource already stands at 38.5Moz AgEq, and the latest drilling indicates the system continues materially below that existing estimate. If future drilling converts those deeper extensions into reportable resources, the underground component of Achilles could expand considerably.

2. A Second Resource Opportunity Is in Progress

At Browns Reef-Evergreen, the current drilling campaign is aimed at supporting an initial resource estimate. This creates an additional catalyst independent of Achilles and may broaden AGC's project base if the upcoming work continues to return mineralisation.

3. The Company Retains Funding Flexibility

The company's capital structure, as cited in the ASX material, is as follows.

A debt-free balance sheet does not remove funding risk from future exploration and development. However, it does mean the company is not currently carrying borrowings while executing its drilling programs, which is a constructive position to be in.

What This ASX Update Means in Practical Terms

This ASX announcement adds weight to the idea that Achilles may become larger than its current published resource suggests. The deepest hole drilled to date has also returned the strongest result from the recent deep program, which is a constructive combination from a geological perspective.

Just as important, the company is not relying on a single workstream. While investors wait to see whether deeper Achilles drilling is incorporated into a future resource update, AGC is also moving ahead with shallow drilling at Achilles, resource-definition work at Evergreen, field programs at Junee, and interpretation work at Tooronga.

For now, the key factual takeaway from the report is clear: Achilles mineralisation has been intersected to at least 540m down dip from surface, well below the current resource boundary, and AGC believes those results support further assessment of underground growth and longer-term development options.

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