Cornish Tin Ltd has completed the first three drill holes in its phase III lithium exploration programme at its new extension area of Tregonning South, Cornwall.
SHEETS
The company’s targets include “lithium-enriched aplite-pegmatite sheets” which it previously discovered at Tregonning North.
Returns to date include 0.3 metres at 1.33% lithium oxide and peak grade of 1.4% lithium oxide.
Cornish Lithium also aims to demonstrate that the sheets continue across 3.27 km, from the northernmost intercept at Tregonning North to Megiliggar Rocks at the southern boundary of the project.
The company said that sheets were visible in the cliff face with widths of up to around 2.5m, while the three completed drill holes have intercepted sheets at “various levels”.
The Valley sheet, nearest to the surface, was intercepted in each of the three holes with the true widths of the sheet as 5.31m, 6m and 6.8m, respectively.
The three holes also intercepted a “slightly deeper level of sheets”, which tended to more of a “cluster pattern”.
Phase III drilling follows 9,277.6m diamond core drilling in the first two phases, of which 7,272.6m targeted tin at Great Wheal Vor and 2,005m targeted Tregonning lithium.
New discoveries of “multiple high grade tin structures” so far include the Goldilocks Cluster, Metal North, Hichens Lode, St Pirans.
Founder and chief executive officer Sally Norcross-Webb added that Tregonning was of “great importance” to the UK.
“The JORC exploration target report [67 to 328 million tonnes grading at 0.26 – 0.32% lithium oxide] of February 2025 on Tregonning North demonstrates the enormous potential of the new lithium field discovered by Cornish Tin.
“Tregonning South has never before been explored using modern methods, but the prevalence and widths of the aplite-pegmatite sheets we have discovered so far in phase 3 are very significant.
“We are also aiming to implement our next tin-focused exploration drilling program in 2026, if funds allow.”
Cornish Tin currently holds £16.67 million for equity funding.
Phase III drilling began in September 2025 and is due to end by January 2026, with assay results expected during Q1 2026.
GRANITE
Tregonning is on the western part of the Great Wheal Vor project, which comprises 26 past producing tin and copper mines in the mining district of Breage, while Carnmenellis granite lies to the east.
Tregonning granite, a G5 granite or topaz granite, lies beneath much of Cornish Tin’s exploration area.