Astral Resources NL (ASX:AAR) earlier this week provided an update on drilling and development activities at its flagship Mandilla Gold Project in Western Australia, with managing director Marc Ducler outlining growing confidence in the depth potential of the Theia deposit.
Speaking with Proactive, Ducler said recent deep diamond drilling had delivered strong geological indicators, including quartz veining, visible gold and sulphides, suggesting the mineralised system could extend significantly beyond current resource boundaries.
The company completed a conceptual underground mining study earlier this year before launching the drilling campaign, with Ducler explaining that Astral Resources wanted confidence that deeper mineralisation could ultimately support underground extraction.
Two drill holes have now been completed, both extended well beyond their original target depths after encouraging observations during drilling. One hole was increased from 560 metres to 690 metres, while the second was extended from 520 metres to 775 metres.
Ducler said the company expected upcoming assay results to confirm the scale of the opportunity.
“We expect that when those assays start to come through that we will be able to demonstrate that we have significantly increased the depth potential of Theia as a deposit,” he said.
Alongside the deep drilling campaign, Astral Resources continues to advance a three-phase RC infill drilling program aimed at supporting the Definitive Feasibility Study (DFS) for Mandilla. The company recently updated the resource model for the first development panel, delivering measured resources and improved reconciliation outcomes.
Ducler noted grades increased by around 5%, with contained ounces also improving.
The company is also assessing the high-grade Five Mile deposit at Spargoville, acquired as part of the Spargoville transaction. While relatively small compared to Astral Resources’ broader 2.1-million-ounce resource inventory, the deposit may play an important strategic role due to its proximity to planned mine infrastructure.
According to Ducler, the deposit remains open at depth and a revised resource estimate is expected later this year.
Astral Resources also recently acquired the Mandilla homestead, a move designed to reduce permitting complexity and remove potential development constraints linked to nearby residential impacts.
Looking ahead, investors can expect initial diamond drilling assay results from mid-May, while the company is also targeting progress on its Think Big joint venture with Matsa Energy and a related pre-feasibility study.
Key interview highlights
- Astral Resources has completed two deep diamond drill holes at the Theia deposit within the Mandilla Gold Project.
- Both holes were extended significantly beyond planned depths due to encouraging geology.
- Drilling intersected quartz veining, visible gold and sulphides.
- The company believes Theia has substantial depth extension potential.
- A conceptual underground mining study supported the deep drilling strategy.
- Ongoing RC infill drilling is supporting the Definitive Feasibility Study (DFS).
- Recent resource updates showed improved grade reconciliation and increased ounces.
- The Five Mile deposit at Spargoville remains open at depth and could support infrastructure planning.
- Astral Resources acquired the Mandilla homestead to simplify permitting and reduce development risk.
- Investors can expect diamond drilling assay results from mid-May.
- Progress is also anticipated on the Think Big joint venture and pre-feasibility study.
Proactive: There is growing upside at Astral Resources’ flagship Mandilla Gold Project, with early diamond drilling indicating the system may extend well beyond current resource limits. New high-grade results from nearby Spargoville also add to the broader development picture. Here to discuss it is Managing Director Marc Ducler. Marc, good to see you again.
Marc Ducler: Likewise.
Proactive: Let’s talk about these drilling results at Theia. Talk us through the results and the potential they add to the Mandilla gold system.
Marc Ducler: We’ve always thought Theia was open at depth. We resisted testing it initially because we wanted confidence that, if those deep holes were successful, we would have a viable pathway to extract the mineralisation.
Earlier this year we completed a conceptual underground study and saw that the economics could stack up. Off the back of that, we launched this diamond drill program.
The first hole was planned for 560 metres and we extended it to 690 metres. The second hole was planned for 520 metres and we extended it to 775 metres. These holes were exceptionally successful, with consistent runs of quartz veining, visible gold and sulphide.
We expect that when the assays come through, we will be able to demonstrate that we have significantly increased the depth potential of Theia as a deposit.
Proactive: And infill drilling is helping progress the DFS as well?
Marc Ducler: Yes. We have two rigs operating. The diamond rig is doing the deep tests and the RC rig is conducting phase one of our three-phase infill program for the remainder of stage one.
The aim is to ensure confidence that the first stage of mine development will deliver on expectations. We’ve already seen encouraging outcomes through the recent resource update, where measured resources were established for the first panel and grade reconciliation improved from indicated to inferred resources.
Overall, grades were up about 5% and ounces were also higher. That work is continuing at the moment.
Proactive: Let’s look at Spargoville as well. What role can the high-grade Five Mile deposit play in the development plan?
Marc Ducler: It’s a 5,000-ounce deposit compared to the company’s broader 2.1-million-ounce resource base, so it’s not material on its own. However, because of its location immediately north of the proposed waste rock landform and tailings dam, it could be strategically important if mined early.
The drilling program there was designed to infill the resource. The Five Mile deposit came from the Spargoville transaction, so it’s new to us and we needed to confirm the mineralisation.
The grades have been encouraging and the deposit remains open at depth. We’ll update the resource estimate later this year and then decide the next steps.
Proactive: Beyond the exploration work, you also bought the Mandilla homestead. Talk us through that decision and what it means.
Marc Ducler: When developing a mine and closure plan, there’s a concept known as a “human receptor,” referring to residents potentially impacted by dust, noise or other operational effects.
The Mandilla homestead had a single resident and there was an opportunity to acquire the property. It was a successful transaction for both sides and simplifies the permitting process, which is one of our key focuses as we progress the DFS.
Proactive: With drilling results still to come, what can investors expect over the next two to three months?
Marc Ducler: We expect the diamond drilling results to start flowing from mid-May. The RC drilling is being processed through different laboratories and turnaround times are currently around 40 to 45 days, which is slower than we’d like.
We’re hoping to release the first diamond drilling results within two to three weeks.
We’ve also spoken previously about the joint venture with Matsa on the Think Big deposit. We’re hopeful of making progress there shortly and potentially executing the joint venture and releasing a pre-feasibility study outlining the revenue opportunity that Think Big could present.
Proactive: Lots to look forward to. Thanks for your time today.
Marc Ducler: Thanks very much.