Astral Resources Extends High-Grade Gold at Mandilla’s Theia Deeps

Theia Deeps Keeps Growing: Astral Resources Delivers More High-Grade Gold Below the Resource Shell

Astral Resources (ASX: AAR) has reported new assay results from its deep diamond drilling programme at the Theia Deposit, the cornerstone asset of the 100%-owned Mandilla Gold Project in Western Australia. The Astral Resources Theia Deeps high grade gold drilling results at Mandilla Gold Project confirm that high-grade gold mineralisation continues to extend beyond the base of the April 2026 Mineral Resource shell, prompting the company to significantly scale up the programme.

Three drill holes, AMRCD262, AMRCD376 and AMRCD378, have returned assay results covering 1,817.3 metres of core, with each hole intersecting broad zones of gold mineralisation sitting outside the current resource boundary. The standout intersection from this batch is 52.75 metres at 4.67 g/t gold from 445.25 metres in AMRCD378, an interval that includes 0.34 metres at 477 g/t gold from 487.3 metres — a visible gold result that underscores the high-grade character of this system at depth.

Reflecting the programme's results to date, Astral has expanded the Theia Deeps drilling campaign from its original scope of 6 holes (3,000 metres) to 21 holes (11,000 metres), more than a threefold increase. Thirteen holes have been completed to date.

The Headline Numbers: What the Three New Holes Returned

AMRCD378: The Standout Hole

AMRCD378 is described as the most significant result in this release. Drilled to 605.2 metres on a south-west azimuth, the hole intersected several intervals that, according to the company, extend the Theia deposit at depth to the south.

The company notes that the 52.75-metre interval at 4.67 g/t sits entirely outside the current mineral resource boundary and represents potential additional material for future resource update work.

AMRCD376: Confirming Resources and Extending at Depth

Drilled 200 metres north-east of AMRCD260, this hole returned results that both support existing Inferred Mineral Resources and extend the deposit's footprint at depth, according to the announcement.

The combination of the 45-metre and 64-metre intervals below the April 2026 Mineral Resource shell points to lateral and vertical continuity of the gold system at this location.

AMRCD262: Deep Bulk Intervals Open Along Strike

This hole was drilled to 631.7 metres, the deepest of the three, returning a package of broad, lower-grade intervals at depth.

When the four deep intervals between 470 and 606 metres are combined, allowing for up to 15 metres of internal waste, they bulk out to 136 metres at 0.76 g/t gold, indicating scale to the mineralised system at depth. Furthermore, the company notes potential for this mineralisation to extend up-dip to the south, which future drilling is intended to test.

Managing Director Marc Ducler said: "The Theia Deeps drill program, which has now been extended to 21 holes for 11,000m, continues to show tremendous potential for additional growth at Theia, with the program targeting further high-grade extensions to the Theia resource at depth and along strike.

"These programs position Astral for a very active second half of 2026 as we continue to both de-risk and grow the Theia deposit, advance the Mandilla Project DFS and kick-off a series of very promising exploration programs."

Understanding Drill Results: What "Outside the Mineral Resource Shell" Means

One phrase repeated throughout this announcement carries particular weight for investors: mineralisation reported as "outside the Mineral Resource shell."

A Mineral Resource shell is a three-dimensional boundary, modelled using computer software, that defines the volume of rock estimated to contain economically meaningful gold mineralisation. Any gold intersected outside this shell is not yet counted in the company's official resource figure. It represents potential upside that has not yet been captured in existing estimates.

When multiple drill holes consistently intersect broad, high-grade intervals below and beyond this shell — as reported across three consecutive holes at Theia Deeps — it suggests the mineral system may be larger than currently modelled. Consequently, these results are intended to feed into future resource update work, with potential to expand both tonnage and contained gold ounces, subject to further evaluation.

Key terms for reference:

• Mineral Resource Estimate (MRE): The total volume of mineralised material estimated to JORC standards. Mandilla currently holds 1.74 million ounces at 1.0 g/t gold.
• g/t Au: Grams of gold per tonne of rock. The higher the figure, the richer the material.
• Diamond Drilling (DD): A drilling method that extracts a continuous cylinder of rock (core) for detailed geological analysis, generally preferred for deep, precise resource definition work.
• Reverse Circulation (RC) Drilling: Faster and cheaper than diamond drilling, typically used for broader resource definition.
• Inferred, Indicated, Measured: Classification levels for Mineral Resources under the JORC Code, ranging from least confident (Inferred) to most confident (Measured).
• Bulk composite: Multiple adjacent drill intersections aggregated into a single, larger interval that reflects the overall mineralised package, providing a measure of scale.

The Mandilla Gold Project: What Astral Already Holds

Before accounting for any resource growth arising from the Theia Deeps programme, Astral already holds a substantial resource base across three gold projects in Western Australia.

Group Mineral Resources

Group Ore Reserves (JORC Probable)

Ore Reserves have been estimated using a gold price of $3,000 per ounce and conform to the JORC Code 2012 edition. The group's Mineral Resources total more than 2.07 million ounces across its three projects, and the Theia Deeps programme is targeted at growing that figure further.

Project Economics: What the Pre-Feasibility Study Established

In June 2025, Astral released the results of a Pre-Feasibility Study (PFS) for Mandilla. The study was based on a standalone project comprising seven open pit mines feeding a 2.75 million tonne per annum processing facility, with production estimated at 95,000 ounces of gold per year for the first 12 years of mine life.

The base case gold price assumption used in the PFS was $4,250 per ounce, at which the project is reported to return a Net Present Value (at an 8% discount rate) of $1.4 billion. At a gold price of $6,250 per ounce, the NPV is estimated to rise to $2.9 billion.

Metallurgical test work across all four Mandilla deposits — Theia, Iris, Eos and Hestia — has demonstrated high gravity-recoverable gold, fast leach kinetics, gold recoveries described as exceptional, low reagent consumption and coarse grinding characteristics. Management regards these results as a meaningful de-risking factor for the project.

A Definitive Feasibility Study (DFS) is currently underway, with both in-fill RC drilling and deep diamond drilling feeding into that process.

What's Coming Next: An Active Second Half of 2026

Astral has multiple exploration and study programmes running simultaneously across its three projects, with a substantial pipeline of near-term activity flagged.

Mandilla (Theia Deposit):

• Theia Deeps diamond drilling continuing, with 21 holes for 11,000 metres now planned and 13 holes completed
• Additional holes targeting further high-grade extensions at depth and along strike
• RC in-fill drilling of the Theia Stage 1 open pit ongoing, with 193 of 431 holes completed (19,445 of 44,400 metres)
• Assays pending for AMRCD377, with logging indicating consistency with the April 2026 MRE and potential for additional resources at depth
• DFS advancement ongoing

Feysville (Kamperman Deposit):

• Heritage survey scheduled for mid-August 2026
• Extensional drilling to recommence following completion of the survey
• Follow-up planned to earlier drilling that intersected 14 metres at 6.79 g/t gold in FRC463, a hole located outside the current MRE and reported as remaining open at depth

Spargoville:

• Heritage surveys scheduled for early September 2026 for the Wattle Dam and Eagle's Nest complexes
• Exploration programmes to commence at Wattle Dam following survey clearance

Why the Investment Case Is Strengthening

Several factors combine to make this announcement relevant to investors monitoring Astral Resources.

Resource growth is being demonstrated through drilling results. Each of the three holes in this release intersected gold mineralisation outside the current resource boundary. The Theia Deeps programme is now 13 holes deep and continues to identify mineralisation at depth. The expansion from 6 to 21 planned holes reflects the results seen so far.

The deposit remains open in multiple directions. AMRCD262 indicates Theia is open at depth at that location, with potential for further vertical extensions. AMRCD376 extended the deposit 200 metres north-east of a prior hole. AMRCD378 demonstrated a high-grade depth extension to the south.

Collectively, these results point to a system that may have material scale beyond what is currently captured in the MRE, subject to further drilling and resource work.

The project already carries a defined economic base. With a PFS-level NPV of $1.4 billion at base case gold prices and a DFS underway, Mandilla has a defined mine plan, an Ore Reserve of 1.082 million ounces, and a processing configuration that has already been scoped and studied. Resource growth from Theia Deeps has the potential to inform future updates to this economic base.

The regional address is well-established. Mandilla is located approximately 70 kilometres south of Kalgoorlie, within a belt that hosts operating mines including Northern Star Resources' Golden Mile Super Pit, Gold Fields' St Ives Gold Mine, and Westgold Resources' Beta Hunt Gold Mine.

Multiple exploration fronts provide optionality. Beyond Theia, Astral holds the Feysville and Spargoville projects. The Kamperman extensional target, following an intersection of 14 metres at 6.79 g/t gold outside the current resource, and the historically mined Wattle Dam complex (266,000 ounces at 10.6 g/t gold) represent additional growth vectors not yet reflected in the group's 2.07 million ounce resource base.

Why This Company Warrants Continued Attention

Astral Resources is running a multi-rig exploration campaign at a project that already holds more than 2 million ounces in total Mineral Resources and a Pre-Feasibility Study indicating substantial project economics. The Astral Resources Theia Deeps high grade gold drilling results at Mandilla Gold Project continue to deliver intervals extending beyond the current resource boundary, with the programme now more than tripled in scope from its original design.

With the DFS advancing, in-fill drilling at Theia ongoing, and exploration catalysts at Feysville and Spargoville scheduled for the September quarter, the company has flagged a period of substantial activity across its project portfolio in the second half of 2026.

Key takeaway: Astral Resources has built a resource base of more than 2 million ounces across three Western Australian gold projects, supported by a PFS indicating billion-dollar-level project economics at Mandilla. The Astral Resources Theia Deeps high grade gold drilling results at Mandilla Gold Project continue to extend the deposit beyond its current boundaries. With multiple resource, study and exploration catalysts flagged for the months ahead, developments at Mandilla, Feysville and Spargoville warrant continued monitoring by investors.

Want to Know More About Astral Resources and the Mandilla Gold Project?

With over 2 million ounces in total Mineral Resources, a Pre-Feasibility Study pointing to billion-dollar-level project economics, and a Theia Deeps drilling programme that continues to deliver high-grade results beyond the current resource boundary, Astral Resources (ASX: AAR) is shaping up as a compelling gold development story in Western Australia. To learn more about the company, its projects, and the investment case behind Mandilla, Feysville and Spargoville, visit the official Astral Resources website at astralresources.com.au.