Core Lithium’s Grants open pit: early mining and slope notes for engineers
Reviewed by Joe Ashwell
First reported on International Mining – News
30 Second Briefing
Open-pit mining has started at Core Lithium’s Grants deposit, part of the wholly owned Finniss Lithium Operation near Darwin in Australia’s Northern Territory, with initial works focused on drill-and-blast and bulk excavation. The start of pit development moves Finniss from project build into active ore extraction, enabling the company to progress towards first spodumene concentrate from the Grants open pit. Geotechnical teams will now be validating pit wall performance and blast fragmentation in local lithologies to optimise slope design and downstream processing.
Technical Brief
- Initial blasting campaigns at Grants require strict exclusion zones and shotfiring controls near active earthworks.
- Start-up phase will rely on short, conservative benches and catch berms until slope performance is verified.
- Drill-and-blast patterns must be tuned to lithium-bearing pegmatite versus wall rock to avoid overbreak.
- Early geotechnical mapping of blast faces will feed back into pit wall design and hazard zoning.
- Traffic management for mixed fleets in a confined new pit is critical to prevent vehicle interactions.
- Progressive clearing and topsoil stripping around Grants need erosion and sediment controls to protect nearby waterways.
- Emergency response planning now shifts from construction hazards to open-pit risks such as wall failure and flyrock.
Our Take
Within our 135 lithium-tagged pieces, most new Australian supply is concentrated in Western Australia, so Core Lithium’s Finniss Lithium Operation in the Northern Territory diversifies the country’s hard‑rock lithium footprint into a jurisdiction with less established mine infrastructure but relatively streamlined approvals.
Safety‑tagged project coverage in our database often highlights early-stage controls around new open pits; for Grants open pit this likely means particular scrutiny on wall stability and traffic management as the operation transitions from pioneering to routine ore extraction.
International Mining appears across both this Finniss Lithium Operation item and future-facing events like the World Mining Congress 2026, signalling that operational developments at assets such as Grants deposit are increasingly being framed for a global audience concerned with secure lithium supply chains.
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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