Astral Resources Hits 52.75m at 4.67g/t Gold Below Mandilla Resource Shell
Astral’s Theia Deeps drilling keeps growing beyond the 1.74Moz Mandilla resource
Fresh deep diamond drilling at Astral Resources’ Theia Deposit continues to intersect broad zones of gold mineralisation below the April 2026 Mineral Resource shell at the Mandilla Gold Project in Western Australia, approximately 70km south of Kalgoorlie. Three holes — AMRCD262, AMRCD376, and AMRCD378 — delivered 1,817.3m of assays, with the standout intercept coming from AMRCD378: 52.75m at 4.67g/t Au from 445.25m. The company has expanded the program from the original 6 holes (3,000m) to 21 holes (11,000m), with 13 holes now completed. These intercepts sit outside the current resource shell, signalling growth potential for a deposit already holding a 1.4Moz Theia component within Mandilla’s 1.74Moz total.
The drilling program targets extensions of an existing, defined asset — de-risking the project whilst testing the deposit’s vertical and lateral limits. Results continue to demonstrate that Theia remains open at depth and along strike, positioning the company to feed material into the ongoing Mandilla Definitive Feasibility Study.
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The standout intercepts driving the story
The three headline hits below were flagged by management as the best intercepts from the latest batch — all located outside the April 2026 Mineral Resource shell and demonstrating the scale of mineralisation at depth.
- 52.75m at 4.67g/t Au from 445.25m — AMRCD378
- 45m at 1.39g/t Au from 389m — AMRCD376
- 25m at 1.68g/t Au from 546m — AMRCD262
| Hole | Best Intercept | Notable High-Grade Sub-Interval | Position vs Resource Shell |
|---|---|---|---|
| AMRCD378 | 52.75m @ 4.67g/t Au from 445.25m | 0.35m @ 47.2g/t; 0.34m @ 477g/t | Outside/below shell |
| AMRCD376 | 45m @ 1.39g/t Au from 389m | 0.3m @ 35.8g/t; 4.4m @ 11.6g/t (from 197.6m) | Extends at depth |
| AMRCD262 | 25m @ 1.68g/t Au from 546m | 0.38m @ 28.1g/t from 494.3m | Outside/below shell |
AMRCD262 also returned a bulked interval of 136m at 0.76g/t Au from 470m (with a maximum 15m internal waste), demonstrating that Theia remains open at depth. AMRCD376 supports both existing Inferred Resources (36m at 1.00g/t from 302m) and confirms depth extension, with the 45m at 1.39g/t Au from 389m intercept sitting well below the current resource shell.
Marc Ducler, Managing Director
“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… These latest assay results… have all demonstrated broad zones of high-grade gold mineralisation beyond the base of the current April 2026 Mineral Resource shell.”
What “drilling beyond the resource shell” actually means for investors
A Mineral Resource shell is a pit-constrained envelope defined at a set gold price — in this case, A$4,500/oz for Mandilla. It represents the three-dimensional boundary of economically viable material that can be extracted under current assumptions. When a company reports drilling intercepts outside or below that shell, it signals that mineralisation extends beyond the current defined resource.
However, an intercept is not the same as a defined Resource. Drill results must be incorporated into a future Mineral Resource Estimate before they count as ounces. Until then, they serve as geological evidence that the deposit is open and could grow in subsequent resource updates.
For investors, successful depth extensions could significantly enhance the open pit economics by increasing the total inventory of economically extractable gold. In this case, the intercepts reported sit outside the April 2026 MRE shell, suggesting potential for future resource expansion at Theia.
The bigger Mandilla picture — resources, reserves and the DFS ahead
These drilling results feed into a broader asset base that investors are buying into. The company’s April 2026 Mineral Resource Estimate for Mandilla sits at 53.5Mt at 1.0g/t Au for 1.74Moz, comprising:
- 1.3Mt at 1.3g/t Au for 57koz Measured Mineral Resources
- 32.6Mt at 1.0g/t Au for 1,092koz Indicated Mineral Resources
- 19.6Mt at 0.9g/t Au for 588koz Inferred Mineral Resources
At the group level, the total Mineral Resource across Mandilla, Feysville and Spargoville stands at 61.6Mt at 1.0g/t Au for 2.07Moz. The group Ore Reserve is 36.6Mt at 0.9g/t Au for 1,082,000oz.
The company’s June 2025 Pre-Feasibility Study envisaged a standalone project producing 95koz per year for the first 12 years from a 2.75Mtpa processing plant. At a base case gold price of A$4,250/oz, the PFS delivered an NPV8 of $1.4 billion, rising to $2.9 billion at A$6,250/oz.
Drilling at Theia Deeps feeds directly into the ongoing Mandilla Definitive Feasibility Study. Growth today underpins the economics of the definitive study and supports the company’s objective to advance the project towards a Final Investment Decision.
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A busy second half of 2026 — what comes next
The company has mapped out a forward roadmap that positions it for an active exploration and development program through the remainder of 2026:
- Theia Deeps DD program — ongoing, targeting further high-grade extensions at depth and along strike.
- Theia in-fill RC program — ongoing, with 193 of 431 holes (19,445m of 44,400m) completed.
- Kamperman (Feysville) extensional drilling — recommencing in the September Quarter, following a mid-August heritage survey. Drilling follows up earlier results including 14m at 6.79g/t Au in FRC463 (open at depth, outside the current MRE).
- Heritage surveys at Wattle Dam and Eagle’s Nest complexes — scheduled for early September to clear the path for Spargoville exploration.
Marc Ducler, Managing Director
“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…”
The company is systematically testing depth extensions at its flagship Theia Deposit whilst laying the groundwork for exploration at Kamperman and Spargoville. The combination of resource growth drilling and project de-risking supports the dual objectives of expanding the asset base and advancing the DFS towards completion.
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