Britain’s only tin mine could end up exporting much of its future production to the United States after the American government signalled it is prepared to provide up to $225 million (£166 million) in financing to revive the historic South Crofty site in Cornwall.
Cornish Metals, which is working to bring the South Crofty mine near Camborne back into production, has received a letter of interest from the Export-Import Bank of the United States (Exim), proposing a potential financing package linked to supplying tin to the US market.
The move comes less than a year after Cornish Metals secured a £28.6 million equity investment from the UK’s government-backed National Wealth Fund, which was framed at the time as supporting a domestic supply of a strategically important mineral.
In its statement, Cornish Metals said Exim’s interest was explicitly tied to South Crofty providing a “responsible supply of tin concentrate” to the United States, as Washington seeks to strengthen critical mineral supply chains and reduce dependence on overseas producers.
The company estimates it will cost around £198 million to restart the mine by mid-2028, with both costs and timelines increasing over the past year. It is now seeking to secure funding to cover capital expenditure and operating costs as it moves towards production. Shares in Cornish Metals rose 2.7 per cent following confirmation of Exim’s interest.
Tin is classed as a critical mineral and is widely used in electronics, renewable energy systems and advanced manufacturing. The UK currently has no domestic tin production, and South Crofty is expected to produce an average of around 4,700 tonnes of tin concentrate annually in its first five years, roughly equivalent to the UK’s total yearly consumption.
Fawzi Hanano, Cornish Metals’ chief development officer, said the US financing proposal would inevitably come with expectations around offtake.
“Exim would not give money to a foreign entity unless there’s something in it for them,” he said. “Ideally they would want all of the production, but in reality it would be a certain percentage that aligns with the level of financing being provided.”
He confirmed that none of South Crofty’s future output is currently committed to buyers and that there is no obligation for the mine to supply UK customers, despite the National Wealth Fund’s involvement.
One of the challenges, Hanano said, is that while the mine will produce a high-grade tin concentrate, the UK and Europe currently lack the smelting capacity needed to process it into refined tin metal.
“There is no smelting capacity in the UK or Europe at present, so there is no outlet for tin concentrate domestically,” he said. While the US also lacks significant smelting capacity today, it is in the process of developing it as part of its critical minerals strategy.
Hanano suggested that government-to-government agreements could still allow for some tin to flow back to UK end users in the future. “If one country has upstream capacity and another has processing capability, there are structures where material can be processed and some of it returned. That’s ultimately a decision for governments to take.”
The potential deal highlights growing geopolitical competition for critical minerals, and raises questions over how far UK-backed resource projects may ultimately serve domestic industry when global supply chains, and foreign state financing come into play.