Astral’s 1146g/t gold at Theia Deeps: underground potential for mine planners
Reviewed by Tom Sullivan

First reported on Australian Mining
30 Second Briefing
Astral Resources has reported a record intercept at the Theia deposit, with 0.34m at 1146.3g/t gold within a broader 31m zone grading 13.5g/t from 288m depth in diamond hole AMRCD468A at the Mandilla project, about 70km south of Kalgoorlie in Western Australia. The ultra-high-grade shoot at Theia Deeps, defined in competent fresh rock, points to strong underground potential beneath existing open-pit resources and will likely drive tighter structural modelling and targeted deep drilling.
Technical Brief
- Assay represents Astral Resources’ highest individual gold grade recorded at Mandilla to date.
- Intercept occurs within Theia deposit, part of the broader Mandilla gold project tenure.
- Similar ultra-high-grade shoots in WA orogenic goldfields have historically supported narrow-vein, high-margin underground operations.
Our Take
Our database shows a sequence of escalating grades at the Theia deposit, from 1m at 219g/t in the 9 September piece to this 1146.3g/t hit at Theia Deeps, suggesting Astral Resources is progressively vectoring into a very high-grade shoot at depth rather than isolated spot highs.
The 31m zone at 13.5g/t at Mandilla, combined with Astral Resources’ recent $9.05 million move to secure unfettered control over the project tenure (28 September article), indicates the company is now backing a potential long-life, higher-margin core asset rather than a satellite deposit.
Astral’s doubling of the Spargoville gold resource (12 October article) alongside these Mandilla results positions the company as one of the more active gold resource growth stories in Western Australia within our recent Mining–Projects coverage, which may influence how it sequences development between Spargoville and Mandilla.
Prepared by collating external sources, AI-assisted tools, and Geomechanics.io’s proprietary mining database, then reviewed for technical accuracy & edited by our geotechnical team.
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