Much progress in producing lithium from mica in Cornwall

The global demand for lithium is expected to outpace supply over the coming decades, a recent analysis by the International Energy Agency suggesting that the world's current supply of lithium will meet only 50% of global demand by 2035. Governments around the world have responded by advancing the rapid development of their lithium resources, including hard-rock mineral deposits. 

In west Cornwall Cornish Lithium is currently testing different technologies to extract the metal from the hot geothermal brines a kilometre below the earth, and after removing the lithium injecting the water back underground so the process can be repeated. The energy used to power this process will be from a renewable source, the natural heat from the deep rocks being converted into electricity, making the process carbon-neutral

In East Cornwall, however, two companies, Cornish Lithium and British Lithium, are developing flowsheets to extract lithium from zinnwaldite, a lithium containing mica, found in the decomposed granite which forms kaolin, mined in the St.Austell region by Imerys as china clay.

Imerys is a French multinational company, which, a year ago, acquired an 80% stake in British Lithium, based in the same area, the transaction bringing together Imerys’ expertise in mining, R&D and process development capabilities, as well as its lithium mineral resources, with British Lithium’s bespoke technology and state-of-the-art lithium pilot plant, which recently produced battery-grade lithium carbonate.

Mineral resources are estimated at 161 million tonnes at a grade of 0.54 % lithium oxide. These resources give sufficient confidence to target a life of mine exceeding 30 years at a production rate of 20,000 tonnes of lithium carbonate equivalent per year, potentially enough to equip 500,000 electrical vehicles per year by the end of the decade, meeting roughly two-thirds of Britain’s estimated battery demand by 2030 when all UK car manufacturers convert to electric vehicles.

Last month Cornish Lithium received confirmation that the Government has directed that the Company’s Trelavour Hard Rock Project, also in the St Austell area of Cornwall, should be treated as a Nationally Significant Infrastructure Project. The UK currently imports 100% of its lithium, and the two projects will reduce the country's reliance on carbon-intensive imported lithium whilst supporting the UK’s green energy transition to Net Zero. 

Two years ago I visited the Trelavour site to see how things were proceeding, but was disappointed to see only an empty shed!  That shed is no longer empty, as last week the Demonstration Processing Plant was launched, a huge milestone for Cornish Lithium,  but more importantly for the UK. 

Photos courtesy of David Goldburn

The Demonstration Processing Plant will allow Cornish Lithium to test and confirm the viability of extracting lithium from hard rock in Cornwall, before scale-up to full size production. The plant will take lithium-enriched granite, mined from a repurposed china clay pit and process it to produce battery-grade lithium hydroxide using low-carbon processing technology, all on one site.

It is forecast that Cornish Lithium will contribute at least £800 million to the local economy and create over 300 well paid jobs for local people. This project will also drive investment across the entire supply chain, supporting businesses from St Austell to the Scottish Highlands. Trelavour combined with the planned geothermal lithium production will contribute around 25% of the UK’s forecasted demand by 2030. 

Together the two companies could create around 860 jobs in the county and if the mines and processing plants attract investment for a battery factory a further 3,000 jobs could be created.