Astral Resources NL (ASX:AAR) has pointed to growing upside at its flagship Mandilla Gold Project in Western Australia, with early diamond drilling indicating the system may extend well beyond current resource limits, while new high-grade results from nearby Spargoville add to the broader development picture.
The update combines early-stage visual results from deep drilling at the Theia deposit, ongoing work to support a definitive feasibility study (DFS) and fresh assays from the 5B deposit at Spargoville — all feeding into the company’s push to advance Mandilla towards development.
Map illustrating the location of the Mandilla, Spargoville and Feysville Gold Projects.
Deeper drilling points to larger Theia system
At Mandilla, drilling is targeting extensions beneath the existing mineral resource at the Theia deposit, which already hosts a substantial portion of the project’s 1.74Moz resource base.
Astral has completed two of six planned diamond holes, with both extending well beyond their original target depths and intersecting strong quartz veining and visible gold.
Orthogonal view of target areas (green, red and blue) with light blue drill traces of planned diamond drilling and dark blue squares showing RC drill collars.
These visual indicators — particularly quartz veining, which closely correlates with gold mineralisation at Theia — were logged as deep as around 360 metres below the base of the current pit design.
Managing director Marc Ducler said the early results suggest the mineral system could continue significantly deeper than previously defined, with the program now expanded.
“The current deep diamond drilling program at Mandilla’s cornerstone Theia Deposit is designed to scope the potential scale of the Theia gold mineral system,” he said, noting extensions of up to 380 metres below the existing resource are being considered.
Isometric view of the Theia Deposit showing the MRE block model, the quartz vein percentage values of the two most recent DD holes drilled and the cross-section location.
Assay results are expected in June, but the visual logging has already been enough to justify adding three more holes to the program, lifting the total planned drilling to 5,500 metres, Ducler added.
Alongside this work, reverse circulation drilling continues to infill the proposed Stage 1 open pit, with around 5,000 metres completed as part of a larger 23,000-metre program aimed at upgrading resource confidence ahead of mining.
Cross-section view of the Theia Deposit showing the MRE block model, logged visible gold and the quartz vein percentage value. (inset picture AMRCD263 NQ2 diameter core at 518.2m).
Land acquisition streamlines approvals
Astral has also moved to simplify development approvals at Mandilla, acquiring the 21-hectare Mandilla Homestead for $850,000.
Located less than 500 metres from the proposed processing plant site, the freehold land purchase removes the risk of proximity to residents and is expected to streamline permitting.
The site could also serve as a future operational base, allowing relocation of infrastructure currently located offsite.
Plan view of Mandilla Gold Project showing the location of Mandilla Homestead (red outline) relative to the planned infrastructure locations from the Mandilla PFS.
High-grade Spargoville results add near-term optionality
At the nearby Spargoville Gold Project, a 12-hole RC drilling program at the 5B deposit has delivered a series of high-grade intercepts, confirming and extending known mineralisation.
Key results include:
- 9m at 4.38 g/t gold from 108m, including 2m at 10.3 g/t
- 4m at 8.31 g/t from 97m, including 1m at 29.1 g/t
- 4m at 4.95g/t from 100m, including 1m at 13.4 g/t
The drilling was designed to validate historical results and infill gaps within the current resource model, with outcomes confirming a consistent high-grade component within the deposit.
Map of the 5B deposit illustrating drill collar locations of recent and historical drilling on local area geology.
Ducler said the results highlight the potential for early-stage mining at 5B, particularly given its location relative to planned Mandilla infrastructure.
“With confirmed high-grade mineralisation in the recent results… there appears to be a clear high-grade component to the gold mineralisation at the contact of a hangingwall ultramafic unit with a footwall basalt,” he said, noting the work will feed into a broader resource update scheduled for the September quarter.
The 5B deposit currently hosts a modest inferred resource of around 5,000 ounces, but its proximity to proposed waste dumps and tailings infrastructure means it could play a strategic role in early project development.
Cross section of the 5B deposit (looking 000) illustrating historical drill traces, recent gram-metre gold intersections and the MRE block model.
Building momentum towards development
Mandilla sits about 70 kilometres south of Kalgoorlie and is emerging as a significant standalone gold project, underpinned by a 1.74Moz resource and a pre-feasibility study outlining a multi-pit operation.
That study envisaged annual production of around 95,000 ounces over an initial 12-year mine life, with strong economics at prevailing gold prices.
With drilling now targeting deeper extensions, infill programs advancing, and nearby deposits like Spargoville continuing to deliver, Astral is steadily building both scale and flexibility into the broader development plan.
The next key catalysts will be assay results from Theia’s deep drilling program and updated resource estimates across the portfolio later this year — both of which could reshape the project’s long-term production profile.