Astral Resources Lifts Mandilla Gold Resource 22% with Measured Category Debut

Mandilla Resource Surges with Maiden Measured Category

Astral Resources (ASX:AAR) has delivered a significant upgrade to its Mandilla Gold Project, announcing a 22% increase in contained gold to 1.74 million ounces within a 54 million tonne resource grading 1.0g/t. This update is notable not only for the jump in ounces but for the inaugural declaration of a Measured Mineral Resource of 57,000 ounces at the Theia deposit, the project’s cornerstone.

The measured category reflects confidence gained from a rigorous 99-hole, 11,121-metre in-fill drilling campaign that tightened drill spacing to 12.5m x 12.5m within the Stage 1 Theia open pit area. This drilling validated the geological model and estimation methodology, with grade and ounce increases of 5.2% and 4.2% respectively compared to previous wider-spaced drilling.

Group Resource Now 2.07 Million Ounces with Higher Gold Price Assumptions

When combined with Feysville (196,000 ounces) and Spargoville (139,000 ounces), Astral’s consolidated Group Mineral Resource Estimate reaches 2.07 million ounces across 62 million tonnes at 1.1g/t gold. The updated Mandilla MRE was calculated using a gold price assumption of A$4,500 per ounce, up from A$3,500 in the prior estimate, reflecting a more bullish pricing environment for resource optimisation.

Despite the higher gold price assumption, Mandilla’s contained gold still increased by 15% on a like-for-like basis, underlining the robustness of the resource growth. Theia alone accounts for roughly 80% of Mandilla’s resource, now estimated at 1.39 million ounces, up 233,000 ounces from the previous estimate.

This substantial resource growth at Mandilla follows a series of successful drilling campaigns and fits into the company’s broader strategy to advance its Western Australian gold assets, as recently highlighted in the company’s strong drilling and placement update supporting the Mandilla DFS progress Mandilla DFS with Robust Drilling.

Depth Extensions and Underground Mining Potential

Importantly, the Theia deposit remains open at depth, with a current six-hole diamond drilling program underway targeting up to 175 metres below the known mineralisation. Early results from the deepest hole to date confirm that the mineralised environment extends well below the existing pit shell, reinforcing potential for future resource expansion.

Given this open-ended depth potential, Astral is actively evaluating underground mining options for Theia. A high-level conceptual study suggests that underground mining and processing costs could be competitive, supporting a 1g/t cut-off at the prevailing gold price assumptions. This pivot towards underground mining consideration marks a strategic shift from previous open-pit-only plans and could materially extend the mine’s life and value.

Definitive Feasibility Study and Approvals Advancing

The Mandilla Definitive Feasibility Study (DFS) is progressing with mine design work now incorporating the updated MRE. GR Engineering’s workstreams are advancing well alongside ongoing heritage clearance surveys, a critical step given the recent identification of a heritage site on the eastern side of the project tenure.

Exploration continues apace with two rigs operating: a diamond drill rig testing depth extensions and an RC rig focused on in-fill drilling to upgrade resource confidence ahead of mining, slated to commence in the second half of 2027. The in-fill program aims to elevate the entire Stage 1 Theia open pit to Measured Resource status, reinforcing the early years of mine production.

Exploration Momentum Across Portfolio

Beyond Mandilla, Astral is progressing a joint venture agreement at Feysville with MMS and preparing for renewed drilling at Spargoville after planned heritage surveys. These projects add further optionality and growth potential to Astral’s portfolio, complementing the flagship Mandilla asset.

The company’s comprehensive approach combines resource growth, feasibility advancement, and environmental and heritage management, positioning it as a notable emerging gold producer in Western Australia.