Critical Metals’ Tanbreez HREE corridor: resource and pit design notes for engineers
Reviewed by Joe Ashwell
First reported on MINING.com
30 Second Briefing
Critical Metals’ 2025 drilling at the Tanbreez project in southern Greenland has extended rare earth mineralisation over a 1,750-metre corridor at Area B, with TREO grades typically 0.35%–0.61% and heavy rare earths comprising up to 27% of the total. Final holes at the Fjord deposit returned consistent >0.4% TREO plus gallium, hafnium, cerium and yttrium, supporting further extension and infill drilling in 2026 to refine pit designs and resource models. Tanbreez currently hosts at least 45 million tonnes within a 4.7‑billion‑tonne intrusive body, underpinning a PEA NPV of about $3 billion and a phased ramp-up from 85,000 to 425,000 t/y REO.
Technical Brief
- Preliminary economic assessment reports a pre-tax NPV between $2.8–$3.6 billion at 15–12.5% discount.
- Current defined resource is split roughly 50/50 between the Hill and Fjord deposits.
- Mineralised host intrusion is ~5 km by 2.5 km, several hundred metres thick, totalling ~4.7 billion tonnes.
- Existing resource footprint covers only ~1% of the mapped intrusive body, indicating substantial upside drilling inventory.
Our Take
With Tanbreez’s host rock estimated at 4.7 billion tonnes and the current resource covering only about 1% of that, the scale suggests Critical Metals could justify multi-phase mine planning and staged processing expansions rather than a single-build plant, which is unusual even among the 88 rare-earth keyword pieces in our database.
The very high pre-tax IRR of around 180% and NPV of roughly $3 billion put Tanbreez at the aggressive end of rare earth project economics in our coverage, which is likely to strengthen Critical Metals’ hand in any future US-facing offtake or funding discussions hinted at in the 14 January 2026 item about its mobile assay lab purchase involving the US government and White House.
Taken together with the 7 January 2026 article on Critical Metals’ turnkey pilot facility in Qaqortoq, the confirmation of high-grade HREEs at Tanbreez points to a deliberate strategy to lock in Arctic-capable logistics and testwork infrastructure ahead of a potential 2026 start, reducing execution risk that often delays Greenland projects in our mining database.
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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