Core Lithium’s Finniss restart: underground BP33 contract insights for planners
Reviewed by Joe Ashwell

First reported on Australian Mining
30 Second Briefing
Core Lithium has awarded a $274 million underground mining contract at the Finniss lithium project near Darwin to Dev Mining Services, a subsidiary of Development Global, as part of its restart strategy after open-pit operations were suspended in 2024. The deal covers underground development and production at the BP33 deposit, targeting spodumene ore beneath the existing pit using decline access rather than further cutbacks. For geotechnical and mine planners, the shift to underground at BP33 signals a focus on higher-grade zones and tighter control of strip ratios and operating costs in a volatile lithium price environment.
Technical Brief
- Contract value of $274 million implies multi-year underground development and production scope at BP33.
Our Take
Taken with the circa A$50 million surface mining contract at the Grants deposit (7 April 2026), the Dev Mining Services award signals that Core Lithium is locking in both open-pit and underground capacity at Finniss ahead of a full operational ramp-up rather than a staged restart.
The sequence of pieces in our database – ore reserve upgrade (26 January 2026), Glencore offtake and funding (3 March 2026), FID to restart (19 March 2026), then contracting awards – suggests Finniss is now in an execution phase where schedule risk will hinge more on contractor performance than on financing or approvals.
Within the lithium coverage in Australia, Core Lithium now appears among the more contract-miner-heavy operators, which typically allows faster scaling or curtailment in response to price swings but can leave margins more exposed to contractor cost escalation over the three-year-plus terms being signed.
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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