The Trevalour lithium project, also known as the Trelavour Hard Rock Project, is located approximately 11 km from the town of St Austell in Cornwall, in the southwest of the UK. Currently, the country has no active lithium production, making this one of the few lithium exploration initiatives underway in the UK. The Trelavour Lithium Project is being undertaken exclusively by Cornish Lithium, a UK-based company founded in 2016. The company has emerged as a key player in establishing a new lithium industry in Cornwall, focusing on both brine extraction and hard-rock lithium deposits. In this article, we will focus on its hard-rock lithium project.
The geology of Cornwall is influenced by the Cornubian Batholith — a vast granite body originated approximately 298 to 270 million years ago during the Variscan Orogeny. This granite body intruded into older Devonian and Carboniferous sedimentary rocks and now outcrops across several areas of Cornwall, including St Austell, Carnmenellis, Bodmin Moor, and Land’s End. The intrusion of magma also led to the formation of valuable mineral deposits in the region.
Cornwall’s granite primarily comprises three main minerals: quartz, feldspar, and mica. And the lithium in this granite occurs within the mica minerals. It is important to note that the most common lithium bearing hard rock mineral, spodumene, is not the source of lithium in Cornwall, and the Cornish Lithium’s extraction efforts are specifically focused on mica minerals.
The company is adopting an innovative chemical-based extraction technology that replaces the conventional high-temperature heating process. This approach is regarded as more environmentally sustainable, as it significantly reduces emissions and allows lithium to be extracted with a minimal carbon footprint.
Cornish Lithium already benefits from existing infrastructure at the Trelavour site, which includes a large historic pit previously used for china clay extraction for approximately 250 years and now repurposed for granite mining. Additionally, an old railway line near the site can be utilized to transport materials, significantly lowering logistics costs. The presence of existing power lines and road access further helps reduce overall project expenses.
The company completed test drilling in 2024 to assess lithium resources, and analysis of the results is currently underway. Cornish Lithium also commissioned its low-emission lithium hydroxide Demonstration Plant, which officially opened in October 2024. The facility is designed to carry out the research and analytical work necessary to evaluate the commercial viability of the project.
Cornish Lithium is very confident about the successful completion of test phase of this project, and is aiming to commence commercial production of lithium after the full scale development in 2028. It is estimated to produce around 10,000 tons of lithium carbonate equivalent (LCE) a year – enough for around 200,000 cars. Once the project is fully developed and lithium production begins in 2028, it is expected to supply up to half of the UK’s car battery demand.
In addition to lithium, the Trelavour project could produce valuable by-products, including amorphous silica which is used in cement, concrete, and steel industry; alum, which is potassium aluminium sulphate, and used in water treatment and paper production; potassium sulphate for fertiliser industry; and gypsum, which is a useful material in plasterboard and building materials.
In addition to lithium, the Trelavour Project has the potential to produce several valuable by-products, including amorphous silica—used in the cement, concrete, and steel industries; alum (potassium aluminium sulphate)—used in water treatment and paper production; potassium sulphate—for use in fertilizers; and gypsum—a key material for plasterboard and other building products.
