Astral’s high-grade gold at Theia: design and scheduling notes for mine planners
Reviewed by Tom Sullivan
First reported on Australian Mining
30 Second Briefing
Astral Resources has reported further high-grade gold intercepts from 56 reverse circulation drill holes totalling 4,970m at the Theia deposit within its Mandilla Gold Project in Western Australia. The new assays are being used to upgrade Stage 1 Mineral Resources to the Measured category, tightening confidence in near-surface grade continuity and geometry. Results will directly inform open-pit design, geotechnical domains and initial mine scheduling for the Mandilla development.
Technical Brief
- Short RC hole lengths suggest focus on shallow mineralisation amenable to conventional open-pit mining.
- Consistent high-grade intercepts across multiple holes support robust variography for Measured-category resource estimation.
- RC chip samples will constrain oxide–transition–fresh rock boundaries, critical for pit slope geotechnical domaining.
- Assay density from this programme improves confidence in ore–waste contacts, reducing dilution and ore loss in early benches.
- Upgraded classification at Theia will allow more aggressive cut-back design and tighter strip ratio optimisation.
- Early high-confidence data at Mandilla reduces reliance on conservative geotechnical and mining factors in Stage 1 economics.
Our Take
Astral Resources also reported high-grade gold intersections at the Wattle Dam prospect in its Spargoville project (29 March 2026), suggesting the company is building a multi-asset high-grade exploration story in Western Australia rather than relying solely on Mandilla.
Within our 1265 Mining stories and 418 gold‑keyword pieces, Western Australia gold items like Mandilla typically move from drilling updates to resource re‑statements within a 12–24 month window, so this 56‑hole RC programme at Theia is likely aimed at underpinning the next Stage 1 Mineral Resources upgrade.
The focus on reverse circulation drilling at the Theia deposit aligns with other WA gold projects in our database that use RC as the primary tool for defining near-surface ounces quickly, which can later support scoping or PFS‑level studies without immediately committing to more expensive diamond drilling.
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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