Key UK battery metal projects are edging closer to production. E&MJ reports on the latest developments from the UK Mining Conference in Cornwall
By Carly Leonida, European editor
“We have the opportunity to revitalize an industry that’s been vital to the UK economy for over 4,000 years,” Jeremy Wrathall, CEO of Cornish Lithium and founder of the UK Mining Conference in Cornwall, told the audience when he took to the stage on June 13, 2024.
Now in its fourth iteration, the event, which was held in Falmouth, UK, from June 12-13, showcased the best of British mining today with a nod, of course, to Cornwall’s rich mining heritage. The county, which was once the center of global tin and copper production, now finds itself leading a renaissance, this time as a homegrown source of critical metals and minerals, like lithium, nickel and tungsten. Though the county remains relatively untouched by modern exploration techniques, it’s thought to still hold rich polymetallic reserves which could bolster domestic supply chains for electric vehicles and low-carbon energy technologies.
For example, Sally Norcross Webb, CEO of Cornish Tin, presented results from the company’s latest exploration campaign. Founded in 2017, Cornish Tin has mineral rights covering 26 historic operations that were shuttered in the 1800s after metal prices collapsed, many of which still hold significant reserves. The company’s first exploration drilling program of 2022 uncovered multiple new tin lodes with grades of up to 6.28% tin, as well as significant lithium finds.
Further north, Richard Williams of Peak Nickel spoke to the company’s Rodburn nickel-copper-cobalt project in Aberdeenshire (Scotland) which originally came to light during a 1970s exploration campaign spearheaded by Goldfields but was never developed. A 2023 mineral resource estimate (MRE) found it to contain 4.5 million metric tons (mt) of nickel at a grade of 0.72%. Drilling will continue this year as well as metallurgical test work to support planning ahead of an initial public offering (IPO) in 2025.
The conference program also highlighted a number of operations that are on the cusp of production…
Cornish Metals – bringing South Crofty back to life
Kicking off the first day of presentations, Ken Armstrong, CEO of Cornish Metals, gave the audience a glimpse into rehabilitation and development works at its 100% owned South Crofty project. This was the last UK tin mine to close its doors,13 years after the price collapse of the 1980s. Today, the underground mine is fully permitted to 2071, and benefits from significant power and transport infrastructure left over from its 400-year history. Cornish Metals completed a new preliminary economic assessment (PEA) earlier this year hot off the back of a new 2023 MRE to reflect inferred resources identified through a recent exploration drilling program.
On site, the mine’s water treatment plant has been commissioned and dewatering is underway alongside refurbishment of the Cook’s Kitchen shaft (the project has been rephased to allow the two to happen concurrently). Completion of these activities is expected in Q3 of 2025, and installation and commissioning of the new winders and cages is underway in preparation.
South Crofty is, according to Armstrong, the highest-grade tin project in the world that’s not yet in production. At the peak of its initial 14-year mine life (in years 2-6) it’s expected to produce 4,700 mt/y of tin, equivalent to 1.5% of global supply.
The latest PEA puts the project’s net present value (NPV) at $201 million at an 8% discount and with a 29.8% internal rate of return (IRR) at a base case tin price of $31,000/mt. Pre-production capital is set at $177 million with a payback period of three years after tax. All-in sustaining costs (AISC) are expected to be $13,700/mt making South Crofty a low-cost producer.
Cornish Metals plans to bolster this through upgrading the run-of-mine ore from an average head grade of 0.95% to 1.83% using X-ray transmission (XRT) based ore sorting and dynamic dense media separation (DMS). This will also reduce the amount of material sent to the mill by around 50%, lowering energy and water requirements significantly, and the mine will be fully powered by renewable energy and biofuels.
Armstrong said that Cornish Metals’ ambition is to bring responsible tin mining to Cornwall through South Crofty and, in line with this, the mine plans to store its tailings through paste backfill. Construction of the paste plant is underway with completion expected later this year, and work has begun on the building that will house the mineral processing plant.
First production is expected at South Crofty in 2027, and Armstrong and his team hope to have the mine plan at the feasibility stage by the end of 2024, allowing them to move financing forward and speed development.
Cornish Lithium advances Trelavour
In his presentation, Wrathall gave an update on Cornish Lithium’s efforts at both its Trelavour hard-rock mining project near St Austell in Cornwall and its work on direct lithium extraction (DLE) from geothermal brines.
Trelavour is one of the most advanced lithium projects in Europe. The open pit mine benefits from existing infrastructure, including a railway that runs to the nearest port, and the project will harness an innovative mineral processing technique developed by Australian firm, Lepidico, to extract saleable lithium concentrates from lepidolite (rather than spodumene as most hard rock lithium mines do.)
All elements of the hydrometallurgical section of the demonstration plant are now on site and being assembled into final configuration, while the concentrator section is scheduled for commissioning in July 2024.
Cornish Lithium expects to release a feasibility study for Trelavour in 2025 in parallel with an environmental impact assessment (EIA) for financing, and an environmental and social impact assessment (ESIA) which will feed into planning, with first production slated for 2027.
Meanwhile, work has begun to drill a sixth exploration borehole to a depth of 2-km at the company’s Tolgus project near Redruth to test the flow of geothermal brines through certain geological formations. Cornish Lithium is planning to develop a clutch of low-footprint, low-impact lithium brine projects across Cornwall with the potential for secondary revenue streams through supplying heat and water to local businesses and communities. The company is targeting initial annual production of 15,000 mt/y of lithium concentrate, with the potential in time, for much more.
Wrathall said that Cornish Lithium hopes to drill production boreholes later this year and develop a processing plant at its Cross Lanes Farm site (formerly Twelveheads) near Truro, and recent DLE test work has yielded “encouraging results” using Evove’s selective membrane technology for lithium processing. On-site testing with Koch Technology Solutions to further refine its DLE technology for use on Cornish geothermal waters is also complete.
He concluded by saying that, following 2023 fundraising efforts, the company has around $500 million of equity in place and is ready to move forwards.
Imerys British Lithium forges ahead
In June 2023, Imerys and British lithium formed a joint venture to extract and process lithium carbonate. The company now has two mining projects – one in Cornwall and one in France – from which it plans to produce 50,000 mt/y by 2030.
CEO, Alan Parte, spoke to the progress of the UK project, the aptly named ‘Imerys British Lithium Project’, which is expected to enter production in 2028. The company’s MRE cites an inferred resource of 160.8 mt at 0.54% lithium oxide with a cut-off grade 0.15% ppm. This equates to 2.15 mt of lithium carbonate equivalent, making it one of the largest reported lithium resources in Europe.
The open pit excavation will sit within the footprint of a former kaolin mine, which Parte said has made permitting much simpler, and has an expected 30-year life of mine (LOM). Once operational, the integrated mining and processing complex will produce 21,000 mt/y of lithium carbonate at a capital cost of under £500 million ($634.6 million). The pilot mineral processing plant was completed in 2021 and first concentrate was produced in 2023.
The company has committed to the IRMA standard for responsible mine development and plans to use an electric mine fleet. The pit has a low strip ratio compared to other hard-rock lithium projects and, as mining, beneficiation and refining will take place on site, Parte said the carbon footprint of the final product is expected to be significantly lower than that of others on the market.
Camborne to reactivate engineering offering?
Importantly, it’s not just mines that are being revitalized… A homegrown source of talent will be pivotal to the success of a UK mining renaissance. Pat Foster, Director of the Camborne School of Mines (CSM) at the University of Exeter which ‘paused’ its mining engineering degree course in 2020 (the last on offer in the UK) told the audience that CSM will be making “a big announcement regarding new courses offered from 2025” in the coming weeks (hint hint, nudge nudge).
My overall takeaway from the event? The UK mining industry is just getting restarted. Watch this space!
