Astral Resources Tightens Model at 1.4Moz Theia With 31m at 3.03g/t Gold Hit

Astral Resources' latest Theia in-fill drilling delivers standout intercepts up to 31m at 3.03g/t Au, advancing the Measured Resource conversion that underpins the Mandilla DFS and a $1.4 billion NPV8 gold project.
By William Hadrian -
Summarise with Ai:

Astral’s latest Theia drilling results tighten the model at its 1.4Moz Mandilla gold engine

Astral Resources (ASX: AAR) has reported assays for the next 56 holes (4,970m) of ongoing in-fill reverse circulation (RC) drilling at the Theia deposit, Mandilla Gold Project, 70km south of Kalgoorlie, WA. The results continue to validate the geological model and support conversion of the Stage 1 open-pit inventory to the Measured Mineral Resource category, further de-risking the early years of mine development at the 100%-owned project.

Standout intercepts confirm high-grade shoots within broad mineralisation

The latest batch has delineated broad intercepts of gold mineralisation containing very high-grade shoots within coherent zones of quartz-sulphide veining. Headline hits include:

  • 31m at 3.03g/t Au from 12m, incl. 1m at 59.8g/t (AMRC380)
  • 19m at 2.70g/t Au from 41m, incl. 1m at 36.2g/t (AMRC389)
  • 21m at 2.07g/t Au from 74m, incl. 1m at 14.6g/t (AMRC396)
  • 11m at 3.93g/t Au from 106m, incl. 1m at 34.3g/t (AMRC397)
  • 20m at 2.02g/t Au from 71m, incl. 1m at 22.6g/t (AMRC401)
  • 8m at 2.91g/t Au from 12m, incl. 1m at 19.6g/t (AMRC388)
  • 13m at 2.19g/t Au from 39m, incl. 1m at 12.0g/t (AMRC385)
  • 10m at 2.44g/t Au from 17m, incl. 1m at 19.1g/t (AMRC327)

The average grade of all intercepts in this batch is 1.24g/t Au, which remains well above the Stage 1 Pit MRE grade. Prior in-fill batches averaged 1.93g/t (December 2025) and 1.41g/t (July 2026), demonstrating the consistency of the mineralised system.

Theia In-Fill Drilling: Grade Consistency & Top Intercepts

Marc Ducler, Managing Director

“These results continue to demonstrate the consistency of gold mineralisation within the Stage 1 pit and provide further confidence in both our geological model and the planned conversion of this inventory to the Measured Mineral Resource category.”

Why converting to Measured Resources matters

What “in-fill drilling” and the Measured category actually mean

In-fill drilling reduces drill spacing to increase geological confidence. The three-phase program at Theia is designed to tighten spacing to 12.5m by 12.5m, which will support declaration of Measured Resources across the entire Stage 1 mining inventory. The JORC Measured category is the highest-confidence resource classification, requiring closely spaced drilling and demonstrable geological continuity. This level of confidence is critical for detailed mine planning and project financing.

The de-risking angle for investors

Upgrading Stage 1 to Measured underpins the first 16 months of planned mill feed at Mandilla, a key milestone for the Definitive Feasibility Study (DFS) and project financing. Theia hosts an MRE of 41.0Mt at 1.1g/t Au for 1.4Moz, contributing approximately 75% (1.1Moz) of the Mandilla PFS 1.48Moz production case. The Stage 1 open pit encompasses 4.2Mt at 1.1g/t Au for 146,000oz over the first 21 months of the project at a strip ratio of 4:1.

Metric Figure
Stage 1 open pit inventory 4.2Mt at 1.1g/t Au for 146,000oz
Stage 1 mine life covered First 21 months (16 months of mill feed underpinned by Measured target)
Theia total MRE 41.0Mt at 1.1g/t Au for 1.4Moz
Mandilla PFS NPV8 (A$4,250/oz) $1.4 billion
Mandilla PFS NPV8 (A$6,000/oz) $2.7 billion

Programme progress and what comes next

The in-fill programme remains on schedule, with drilling expected to continue through the remainder of CY2026. Key milestones include:

  1. In-fill programme completed to date: 151 holes for 15,131m of the planned 431-hole (44,400m) programme.
  2. Further 280 holes for 29,300m planned, likely to keep the RC rig utilised for the remainder of CY2026.
  3. Theia Deeps diamond drilling ongoing: 10 of 12 holes (expanded 7,500m programme) complete; assays pending for five holes (2,614m).
  4. Mandilla DFS forecast for completion in the March Quarter 2027, subject to Mineral Rights Agreement consents and native title heritage surveys.
  5. Early mining opportunity at Think Big (Feysville) could deliver cash flow in the June Quarter 2027.

The validation drilling is feeding into the DFS and project financing decisions, positioning Mandilla as a near-term gold production hub in the Kalgoorlie region. The coherent mineralised system at Theia continues to demonstrate the consistency required to underpin early mine development.

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Frequently Asked Questions

What is the Measured Mineral Resource category and why does it matter for Astral Resources?

The JORC Measured category is the highest-confidence resource classification, requiring closely spaced drilling and demonstrated geological continuity. For Astral Resources, converting Stage 1 at Theia to Measured is critical for detailed mine planning, the Definitive Feasibility Study, and securing project financing for the Mandilla Gold Project.

What are the latest Astral Resources Theia in-fill drilling results?

The latest batch of 56 holes (4,970m) returned headline intercepts including 31m at 3.03g/t Au, 11m at 3.93g/t Au, and 19m at 2.70g/t Au, with an average grade of 1.24g/t Au across all intercepts in this round of drilling.

How much gold does the Theia deposit contain?

Theia hosts a Mineral Resource Estimate of 41.0Mt at 1.1g/t Au for 1.4 million ounces, contributing approximately 75% of the Mandilla PFS 1.48Moz production case.

When is the Mandilla Gold Project DFS expected to be completed?

Astral Resources is targeting completion of the Mandilla Definitive Feasibility Study in the March Quarter 2027, subject to Mineral Rights Agreement consents and native title heritage surveys.

What is the NPV of the Mandilla Gold Project?

The Mandilla Pre-Feasibility Study returned an NPV8 of $1.4 billion at a gold price of A$4,250/oz, rising to $2.7 billion at A$6,000/oz, with Theia as the primary production driver.

William Hadrian
By William Hadrian
Partnerships Director
William supports Discovery Alert subscribers across Australia and overseas, helping them tailor alerts, troubleshoot technical issues, and optimise platform settings to suit their workflow.
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