Mauritania’s first uranium mine: Tiris project economics and risk notes for engineers
Reviewed by Tom Sullivan

First reported on MINING.com
30 Second Briefing
Aura Energy’s Tiris project in northern Mauritania is edging towards becoming the country’s first uranium mine, with a bankable feasibility study valuing it at US$500 million despite construction capex rising 52% to US$350 million and the post-tax IRR slipping to 28% on a US$90/lb price deck. The free-dig open pit, requiring no drilling, blasting, crushing or grinding, is planned to produce 46.1 million lb U3O8 over 26 years from 74.6 million tonnes at 227 ppm, but still needs about US$400 million in funding, including potential US$150–170 million DFC senior debt. A pilot plant replicating the full flowsheet will treat over 80 tonnes of ore from November ahead of a December FID, while security planning must integrate with the Mauritanian army in the high-risk Tiris Zemmour region.
Technical Brief
- Construction capex has risen to US$350 million, attributed to more advanced process plant engineering and higher reagent consumption.
- Proven and probable reserves now total 37.3 million lb U3O8 within 74.6 Mt at 227 ppm.
- Aura still needs to secure most of the ~US$400 million development funding, beyond indicative DFC debt.
- A pilot plant in November will run >80 t of ore through the full flowsheet to de-risk design.
- Mine build is expected to take about two years, targeting first uranium production by end-2028.
- Security planning must be integrated with the Mauritanian army, which already controls a 10‑km frontier strip.
- Community acceptance is expected to hinge on demonstrable control of water use and radiation exposure pathways.
- Sahel governance risk is material: Mauritania “renegotiates hard” but, unlike Niger and Mali, has not expropriated mines.
Our Take
With Tiris’ development capex requirement of about US$400 million against Aura Energy’s roughly A$69.1 million market capitalisation, the project is likely to remain highly dependent on external financiers such as the DFC, which can influence schedule, offtake terms and ESG conditions more than in typical mid-tier gold builds like Kinross Gold’s Tasiast expansions in Mauritania.
The 10 km security strip cleared along the Algerian frontier underlines that Sahel security dynamics are now a core design and operating parameter for northern Mauritania projects, and in our coverage of 1251 Mining stories this type of pre-emptive security zoning has usually translated into higher operating overheads and stricter contractor selection for remote open-pit builds.
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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