Twelveheads
Cornish Lithium successfully completed drilling the lithium in geothermal waters exploration borehole in the Twelveheads area in spring 2023. Further work at the site is taking place over 2023 and 2024 to test the waters
From June 2023 until March 2024 further work will be happening at the Twelveheads site for necessary pumping and testwork to analyse the geothermal waters.
- Small scale abstraction pumping as part of extension to existing permissions
- Water will be transported from the site to the United Downs Test Facility and trailed through new DLE technologies
- No drill rig will be onsite
- Work within a secure compound over the previously used site
- Intermitted work at site between 8am – 6pm Monday – Friday
The project sheet for this work is available here:
Previous work:
Successful Twelveheads borehole drilled in 2022 and 2023 provided highly encouraging results:
- Exploration borehole at Twelveheads successfully drilled to a depth of around 1,974m
- Several permeable structures containing lithium-enriched geothermal waters
- Average grade of c.100 parts per million below 1,700m
- Temperature of over 70 °C – end of borehole 72°C
- Low overall levels of total dissolved solids and minimal deleterious elements
Read more information in the press release https://cornishlithium.com/company-announcements/first-half-of-2023-yields-positive-results-and-significant-progress/
Why Twelveheads?
To explore for lithium in geothermal waters, we have created 3D digital models of the geology of Cornwall to identify areas with the most potential for future lithium extraction. In 2019 we drilled two successful research boreholes at United Downs, which confirmed that the geothermal waters are enriched in lithium from depths as shallow as 600 m (c. 2,000 ft). To advance our exploration programme and demonstrate the regional prospectivity of Cornwall, we are currently drilling an additional research borehole just outside of Twelveheads, that will target permeable geological structures approximately 1,600 m (c. 5,250 ft) below the surface. From this research borehole, we plan to recover rock core, which will be analysed and used to identify the location of natural structures in the rock that geothermal waters flow through. An electric pump will be used to pump water samples to surface from these strucutres, which will be analysed for their lithium concentration as set out in the illustration below.
The borehole is being drilled using a small mineral exploration drill rig, like the one we used at United Downs in 2019-2020 .
Drilling Operations
Cornish Lithium commenced drilling the research borehole on 10 March 2022 and it is anticipated that the research borehole will take approximately four and half months to drill, with drilling operations taking place between the hours of 7:00am and 7:00pm each day. Samples of geothermal waters will be collected at intervals down the hole, which is planned to be drilled to a depth of nearly c.1,600m. Some water sampling may take place between 7:00pm and 11:00pm at night, but there will be no drilling after 7:00pm.
If you would like more information about Cornish Lithium’s drilling programme or have any concerns, please contact our drilling team via email, [email protected], or telephone on 01326 640 049.
Community Drop-In Session
To continue our engagement with the Twelveheads’ community, Cornish Lithium will be hosting further community drop-in sessions at the Twelveheads Methodist Church Hall at 4pm to 6pm on the 24th of January and 10am to 12 noon on the 28th of January. Full details of the sessions will be announced in due course. If you are a member of the local community with questions about the research borehole, drilling operations or Cornish Lithium’s work developing an environmentally responsible source of lithium we’d like to hear from you.
