First half of 2023 yields positive results and significant progress

Advisory Board appointed

Cornish Lithium (the “Company”), the pioneering mineral exploration and development company, is delighted to announce significant progress towards the commercialisation of its Lithium in Geothermal Waters projects and strong development progress made at its Trelavour Hard Rock Project, both in Cornwall, UK. The Company is also pleased to announce the appointment of an Advisory Board to provide insight and perspective to support its development.


Geothermal Exploration

  • Exploration borehole at Twelveheads successfully drilled to a depth of around 2,000 metres (“m”)
    • Several permeable structures containing lithium-enriched geothermal waters
    • Average grade of c.100 parts per million (“ppm”) below 1,700m and a temperature of over 70 °C
    • Low overall levels of Total Dissolved Solids (“TDS”) and minimal deleterious elements
  • Fourth geothermal exploration borehole now being drilled at Blackwater.

Geothermal Extraction

  • Low levels of TDS enable the successful use of conventional reverse osmosis technology utilised in desalination processes
    • Lithium concentration increased by a factor of four
    • Significantly reduces the volume of water processed with Direct Lithium Extraction (“DLE”) technology
  • Encouraging test work with KMX Technologies’ vacuum membrane distillation treatment technology
    • Test work has shown the possibility of producing a saleable lithium chloride product
  • Pre-treatment test work completed with Koch Industries ahead of testing Koch’s DLE Pilot Plant in the autumn.

Trelavour Hard Rock Project

  • Significant amount of development work has been undertaken including:
    • Renovating the TreLith processing site in preparation for the Demonstration Plant
    • Addressing the stability of the pit walls to reduce the risk of land slips
    • Upgraded site security to prevent unauthorised access to the pit
  • Resource drilling progressing well with over 5,000m of a 13,000m programme drilled
  • Demonstration Plant progressing well
    • Hazard and Operability Analysis study completed to optimise plant design and safety
    • Long lead items ordered for Demonstration Plant with initial components now on site.

Advisory Board

  • Advisory Board appointed, comprising Kate Holborow, Kate Harcourt and Alverne Bolitho, all of whom have significant experience in ESG (Environmental, Social and Governance), public relations and finance, as well as strong connections to Cornwall.

Jeremy Wrathall, Founder & CEO of Cornish Lithium, said: “Recent results from our borehole at Twelveheads, combined with significant developments in new processes that complement existing Direct Lithium Extraction technology, validates the Company’s original focus on extracting lithium from the geothermal waters that circulate beneath the surface of Cornwall. We are very excited to continue our work towards establishing a source of sustainable, low carbon lithium and contributing to a secure domestic supply of this vital battery metal for the UK. Our work so far furthers our belief that we can develop an industry of significant size and that the commercial extraction of lithium from geothermal waters in Cornwall could create a major new centre for lithium production in Europe.

“Work at our Trelavour Hard Rock Project, which we believe represents one of the most advanced lithium projects in Europe, continues apace. Since signing the leases for the Trelavour Downs Pit and the TreLith processing site, a significant amount of work has been undertaken to improve access to the pit, augment site security and prepare the TreLith site for the Demonstration Plant. We are making significant progress with our further Resource definition drilling campaign as well as with our environmental baseline studies. We plan to commence the Trelavour feasibility study later in 2023.

“It is a testament to the strategic significance of our projects to Cornwall and the UK that we have been able to attract such high calibre candidates to join our Advisory Board. The Company will benefit greatly from the Advisory Board’s experience, in their respective areas of expertise, as well as their knowledge of Cornwall. I welcome and look forward to working with Advisory Board members to further the Company’s success.”

Successful Twelveheads borehole

The recently completed borehole at Twelveheads is the third test borehole drilled by Cornish Lithium. It is situated approximately 2km from the initial proof of concept boreholes drilled at the Company’s United Downs site in 2019 and 2020. The results from the Twelveheads borehole are highly encouraging and are believed to represent a breakthrough for the Company given the grades of lithium encountered during pumping trials.

The Twelveheads borehole was drilled to a depth of 1,974m and encountered four permeable zones, each containing geothermal water and with an average lithium content of c.100 ppm lithium at the final target depth. Results from both the Twelveheads and United Downs sites demonstrate that lithium grade increases with depth. Importantly, the Twelveheads borehole also validated the opportunity to extract significant heat from the water at this depth. The temperature at the end of the borehole was 72°C and temperatures measured in all three boreholes confirm the relationship of increasing temperature with depth. Cornish Lithium believes that this carbon-free heat could be used by local businesses such as dairies, breweries, agricultural greenhouses and regional heating schemes, which would not only benefit communities across Cornwall, but also generate additional revenue for the Company.

Cornish Lithium’s work to date indicates that the characteristics of lithium-enriched waters beneath Cornwall are fundamentally different to other lithium brines encountered around the world on which data has been published. The lithium-enriched water encountered during testing at all three boreholes in Cornwall contains high levels of lithium, but very low levels of overall salinity due to low levels of TDS, which potentially makes it considerably easier to process.  In addition to geochemical testing, Cornish Lithium has undertaken additional hydrogeological test work and airlift pump testing. This has provided a better understanding of achievable flow rates and surpassed previous expectations. These test results will support the modelling projections that are required to assess commercial viability. During recent airlift testing, it was observed that the lithium grade generally continued to rise as the test progressed, which appears to indicate that higher grade water was being drawn upwards from deeper structures. It has not yet been possible to test the maximum achievable grade as recent tests were of short duration.

Importantly, the water encountered in Cornwall at depths of up to 2,000m does not need to be kept at elevated temperature and pressure during treatment with DLE technologies – unlike most other lithium-enriched geothermal brines found elsewhere in the world.

The results from the Twelveheads borehole, in combination with the findings from the original proof of concept drillholes, validate Cornish Lithium’s original subsurface model and can therefore be used to identify new targets within geological structures. The Company has also further demonstrated that the recoverable lithium and heat in water from boreholes drilled to between 1.5km and 2km in depth represent a potentially viable business case without the need to drill significantly deeper, which would incur far higher operational costs.

As a result of encouraging work at its previous three boreholes, the Company is now progressing its fourth exploration borehole at Blackwater. Drilling commenced at the start of April with drilling and testing operations expected to take approximately six months.

Processing progress

Cornish Lithium has also made significant progress regarding defining the processing technologies it plans to use alongside DLE technology. As set out above, the lithium- enriched waters encountered in Cornwall are very distinct from lithium-bearing geothermal brines in other areas of the world due to the very low levels of TDS. Cornish Lithium has now established that simple reverse osmosis treatment, an established technology for seawater desalination, can increase lithium concentration by up to four times. This would bring the lithium concentration post reverse osmosis in line with several projects being developed in South America, with the possibility of further enhancement using additional high-pressure reverse osmosis processes. Concentrating the geothermal brine prior to utilising DLE technology significantly reduces the volume of brine treated and the size of the DLE elements of the geothermal processing plant.

The Company’s DLE Pilot Plant at United Downs has now been reconfigured to test the next DLE technology, which has been provided by SENFI-UK, a subsidiary of SCG. The Pilot Plant has been recommissioned and brine is currently being processed with encouraging results to date. Pre-treatment test work has also been completed with Koch Industries ahead of the delivery of a DLE Pilot Plant, constructed by Koch Industries, to the United Downs site for trials in the autumn.

Cornish Lithium’s processing team has also been testing vacuum membrane distillation treatment technology provided by a US company, KMX Technologies. This work has produced encouraging results that indicate the possibility of producing a saleable lithium chloride product without the need for evaporation.  

Cornish Lithium now intends to evaluate the possibility of building a demonstration-scale lithium and heat extraction plant, and is planning to drill additional exploration targets in order to further increase confidence in the regional model. The Company views the trials being undertaken with Koch’s Pilot Plant in the autumn to be a key element of this work.

The combination of encouraging exploration results and significant advances in extraction technology supports Cornish Lithium’s model of drilling extraction holes across a wide area of Cornwall and creating associated modular, low-impact extraction facilities for lithium and heat production. Furthermore, Cornish Lithium has now spent seven years building a portfolio of mineral rights agreements and detailed three-dimensional models of the subsurface across Cornwall which will underpin the Company’s vision of large-scale lithium production via multiple modular sites across Cornwall.

Development progress at Trelavour

In November 2022, leases were signed with the Tregothnan Estate for the Trelavour Pit and for the TreLith processing site to firmly establish these important development sites for Cornish Lithium. Since these leases were signed, a significant amount of development work has been undertaken by the Company, including:

  • Renovating the TreLith processing site in preparation for the construction of the Demonstration Plant
  • Establishment of new site offices for its geological and engineering teams
  • Improving access to the Trelavour Downs pit as well as enhancing access roads within it to aid drilling operations
  • Improving the stability of the pit walls to reduce the risk of land slips
  • Improving site security through the construction of a new fence and security cameras to prevent unauthorised access to the pit.

The Company continues to make good progress on its latest drilling campaign with over 5,000m of a 13,000m programme drilled to date. The drilling campaign is expected to be completed in the autumn. The updated Resource, in support of the project’s Feasibility Study, is expected to be published by the end of 2023.

A tender process, with a shortlist of preferred engineering firms, is currently underway with a view to work commencing on the Feasibility Study in September.  The environmental studies required to support the Feasibility Study also continue to be progressed and lead ESIA consultants will be appointed in the next few months to align the two processes. 

Contractors have been appointed for the construction of the Trelavour Demonstration Plant, including Lancashire-based Ai Process Systems. The Trelavour Demonstration Plant has been partly funded through a £1.8 million grant from Innovate UK through the Automotive Transformative Fund (ATF). This forms part of the Scale-up Readiness Validation (SuRV) UK Government funding competition secured in September for the hydrometallurgical section of the Demonstration Plant. Initial components for the Demonstration Plant have begun to arrive at the site and completion of the Demonstration Plant is expected in early 2024.

The Company has also now completed a Hazard and Operability Analysis for the Demonstration Plant. This substantial piece of work identified a number of design improvements that were able to be incorporated ahead of the construction of the Demonstration Plant to ensure the safety of operational staff.

Advisory Board appointed

At the end of 2022, the Company formally constituted an Advisory Board with Kate Holborow, Kate Harcourt and Alverne Bolitho invited to join.

Kate Holborow

Born and brought up in Cornwall, Kate (as Kate Wild) is founder of Wild Card, a PR and communications consultancy with offices in Truro, Bristol and London. A Deputy Lieutenant of Cornwall since 2017, she sits on the panel for Young & Talented Cornwall, The Lord Lieutenant’s Fund, leading on fund development and sponsorship. She is co-chair of the annual Cornwall Christmas Fair at the Eden Project, one of the county’s largest fundraisers, which supports Cornish charities through the Cornwall Community Foundation. She sits on The Trelawny Plate Panel, a biannual and prestigious Cornish award made to the individual who has contributed most to the spirit of Cornwall, and co-chairs the Cornwall Lieutenancy Voluntary Sector Committee. Kate has been on the Board of the Cornwall Chamber of Commerce since 2017, is a member of the Lieutenancy Business Committee and was High Sheriff of Cornwall in 2020/21.

Kate Harcourt

Kate is a sustainability professional with more than 30 years of experience across the mining industry and is currently the Company’s ESG (Environmental, Social and Governance) Officer. She works as part of the Owner’s Team with leadership on sustainability issues, and for Equator Principles Financial Institutions and engineering groups. She serves as Non-Executive Director to Condor Gold, Fortuna Silver (transitioning from Roxgold Inc), Orezone Gold Corporation and Atalaya Mining.

She works on projects mainly in Europe and Africa, developing policy and environmental management frameworks, navigating local and international ESIA (Environmental and Social Impact Assessment) processes, stakeholder engagement and permitting, lender liaison, annual reporting and construction supervision. She has joined due diligence teams on high-profile new projects and has contributed to documentation on industry good practice, such as the UNEP (United Nations Environment Programme) Awareness and Preparedness for Emergencies at Local Level for Mining, the IFC (International Finance Corporation) Good Practice Note on Managing Contractors’ Environmental and Social Performance and worked with the Responsible Jewellery Council to update their Codes of Practice (COP).

In 2018, she was nominated one of the Top 100 Global Inspirational Women in Mining.

Alverne Bolitho

Alverne was born and raised in West Cornwall into a family with its roots deep in the local mining community.

Starting his professional life in the military, he has since worked in the City of London for the past 36 years, initially as a stockbroker and more recently in fixed income asset management. Alverne is Managing Director of the London office of New England Asset Management Ltd, which is owned by Berkshire Hathaway.

He is also a member of the London Committee of the Cornwall Community Foundation.  

Cornish Lithium’s Advisory Board members will work closely with its Board of Directors to provide market insight and specific knowledge on key topics, and intelligence to support business planning and alignment to the Company’s strategic goals as well as act as regional ambassadors for the Company. Their significant experience in their specific areas of expertise, combined with their local knowledge and networks, will prove invaluable as the Company progresses its business plan and develops its portfolio of projects.

For further information about Cornish Lithium, please contact:

Neil Elliot, Manager – Corporate Development:

National media enquiries: Wild Card,

Financial media enquiries: BlytheRay,; +44 (0) 207 138 3205

Local/regional media enquiries: Jilly Easterby at Curlew PR;; 07743 164434

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