Astral Resources NL (ASX: AAR) (“Astral Resources” or “the Company”) has delivered another set of outstanding metallurgical results from its Theia Deposit at the Mandilla Gold Project in Western Australia. The latest test work confirms an impressive average 24-hour gold recovery achieved with a coarse grind size, high gravity recovery, and low reagent consumption.
Managing Director Mr. Marc Ducler emphasised the significance of these results, stating:
“Once again, the results are exceptional, achieving an average gravity recovery of 87.6% and an average overall gold recovery after only 24 hours of leaching of 98.2%.”
Key Metallurgical Highlights
Highlights
- Comprehensive Sampling: 234 metallurgical samples were collected across six sections at Theia using 3mm crushed material from Photon analysis sample jars. These samples were combined into six representative sections to provide extensive variability coverage across the deposit.
- Outstanding Recovery Rates: Theia’s gravity recovery averaged 87.6%, with an overall 24-hour gold recovery averaging 98.2%. The minimum recovery observed was 94.7%, while the maximum recovery reached 99.6%
- Coarse Grind and Low Reagent Use: Test work was conducted at a 150µm grind size, 200ppm cyanide concentration, and a pH of 9. The cyanide and lime consumption remained low at 0.35kg/t and 1.90kg/t, respectively, supporting cost-efficient processing.
- Consistent with Prior Results: These findings align with previous test work at Theia, confirming the deposit’s exceptional metallurgical characteristics, including high gold recoveries, fast leach kinetics, and minimal reagent consumption.
- Upcoming Resource Updates: An updated Mineral Resource Estimate (MRE) for Mandilla is expected in the March Quarter, followed by the Pre-Feasibility Study (PFS) in the June Quarter, further de-risking the project.
Figure 1: A map showing the Mandilla and Feysville Gold Project locations
Supporting a Low-Cost Processing Future
The test work indicates that gold extraction at Theia can be achieved with minimal energy and reagent costs. The 150µm grind size means reduced power consumption, while cyanide and lime requirements remain low.
In this context, Managing Director, Mr. Marc Ducler noted:
“These results were achieved using a coarse grind size of 150µm (meaning reduced power consumption) and low reagent consumption, consistent with previous results, which is expected to support low processing costs in the PFS.”
With this strong metallurgical performance, Astral Resources is moving forward confidently with its upcoming Pre-Feasibility Study (PFS).
Mineral Resource Estimate and Pre-Feasibility Study Updates
Astral Resources is preparing to release an updated Mineral Resource Estimate (MRE) for the Mandilla Gold Project in the March Quarter. Following this, the PFS is expected in the June Quarter.
Mr. Ducler stated:
“With the focus firmly on delivering a technically and financially robust PFS, which is expected to occur in the June Quarter, these latest metallurgical results, together with the metallurgical results for the Hestia, Eos and Iris deposits at Mandilla announced to the ASX on 17 December 2024, provide further confirmation of the quality of Mandilla and represent another significant step in de-risking the Project.”
Figure 2: Geological Map of Mandilla Gold Project
Theia Deposit Metallurgical Testwork Results
Astral Resources has previously reported exceptional metallurgical results for Theia, with test work announced on 6 June 2022, demonstrating high gold recoveries and fast leach kinetics in both oxide and fresh rock samples. Further metallurgical test results from Mandilla’s Hestia, Eos, and Iris deposits were reported on 17 September 2024, showing similarly outstanding recoveries.
To further enhance resource confidence, additional variability samples were collected in August 2024 from stored Photon sample jars containing 3mm crushed material. These samples were selected across six cross-sections at Theia, with six bulk samples. The bulk samples were then submitted to ALS Metallurgy for comprehensive test work.
Sampling Breakdown
Samples were sourced from approximately 400-gram Photon assay jars and composited into six bulk sections:
- Section 1: 28 samples, 28 metres, bulk sample 12.6kg
- Section 2: 69 samples, 69 metres, bulk sample 31.0kg
- Section 4: 25 samples, 25 metres, bulk sample 11.2kg
- Section 5: 23 samples, 23 metres, bulk sample 10.4kg
- Section 6: 24 samples, 22.65 metres, bulk sample 10.8kg
- Section 7: 65 samples, 34.74 metres, bulk sample 29.2kg
Each bulk sample was homogenised and sub-sampled for detailed head assay analysis. To determine the optimal processing conditions, 1kg sub-samples underwent grind establishment tests to achieve the 150µm target grind size before conducting gravity and cyanidation leach tests.
Metallurgical Test Process
- The six bulk samples were subjected to six gravity and cyanidation leach tests at the 150µm grind size.
- Gravity testing was performed using a single pass through a laboratory-scale Knelson concentrator, followed by intensive leaching of the gravity concentrate.
- The gravity tail underwent direct cyanidation leaching at a 40% solids density, maintaining 200ppm cyanide concentration and a pH above 9.5 with oxygen injection.
Figure 3: Section Locations of Metallurgical Testing Samples
Expanding Exploration at Feysville
Astral Resources is also advancing its Feysville Gold Project, located near Mandilla. A three-hole diamond drilling program at the Kamperman Deposit is complete, with results expected soon. Additionally, an air-core program has concluded, with assay results due shortly.
A 46-hole RC drilling campaign is scheduled to begin in March 2025.
Maximus Resources Takeover Progress
Astral Resources’ off-market takeover of Maximus Resources is progressing well. The Company now holds approximately 88.16% of Maximus shares. With the offer now unconditional, accepting shareholders will receive Astral shares within ten business days.
Mr. Ducler commented:
“The off-market takeover of Maximus Resources is continuing to progress. With the offer now free of conditions, Maximus shareholders that accept the offer will be issued Astral shares within ten business days.”
Investor’s Outlook
Latest Stock Price
Astral Resources NL (ASX: AAR) has delivered a strong performance over the past year, attracting investor interest with its impressive market gains. The Company’s market capitalisation stands at $212.15 million,with a current share price of $0.155, positioning it near the upper range of its 52-week high of $0.170 (as of March 19, 2025).
Strong Market Performance
Astral Resources has experienced remarkable growth, with its stock price surging 137.29% over the past year. This performance has significantly outpaced both its sector (+145.72%) and the ASX 200 index (+132.17%). The Company’s ability to maintain this trajectory underscores strong market confidence and potential future upside.
Recent Momentum and Year-to-Date Gains
In the short term, AAR has maintained its upward trend, gaining 3.70% over the past week, mirroring its 2025 YTD growth. This sustained positive momentum suggests ongoing investor interest and potential catalysts driving further valuation gains.
