Cornish Tin Ltd reported positive results from its phase II exploration drilling at Great Wheal Vor in Cornwall.
GOLDILOCKS
From February to April, the company completed 2,810 metres diamond drilling with 1,506m focused on tin and 1,304m on the new lithium field intercepted in phase I.
In phase II, drillhole four tested and proved a conceptual tin target, the Goldilocks zone beneath Wheal Vor, in an unexplored zone above the buried granite contact.
“[The target has] nine separate intercepts within a mineralised zone over 155 metres in width (at a vertical depth from approx 100 metres below the Vor historic workings) including grades peaking at 2.37% Sn,” said Cornish Tin.
“Some of the intercepts within this ‘Goldilocks cluster’ also contained high grade copper including 0.47 metres @ 2.57% Cu and 0.49 metres @ 2.91% Cu.
“This proof of concept discovery has far-reaching implications.”
The company added that, based on the conceptual model, the potential tin target zone in the location, predicted to continue down to the granite contact, would be almost three times the size of the Vor historic workings.
Additionally, two new tin lodes were discovered nearer to surface including the new St Piran’s lode with grades peaking at 2.21% Sn.
The company now has seven new tin lodes, of which one is the Goldilocks cluster.
Hole four also intercepted lithium-enriched G5 granite beneath Wheal Vor, at 843m downhole depth, with aplite pegmatite sheets containing tin and lithium in the same core.
The company added that this proved the continuity of the buried G5 granite for 1.2km from outcrop to the intercept.
Drill hole 5 tested the concept of an undiscovered mineralised structure between Vor Main lode to the north, and Wheal Metal to the south.
“This has resulted in the discovery of the new Metal North lode – a significant tin lode including 0.9 m @ 1.5% Sn.
“This is an important new potential high grade tin target zone between the Vor and main historic workings.”
G5 GRANITE
The company noted that the only type of granite in Cornwall containing the high lithium enrichment necessary for viable hardrock lithium mining is G5 granite, also known as Topaz granite.
“It is very rare (only about 1.4% of all Cornish granite outcrop),” added Cornish Tin.
“Of that 1.4%, the major part (about 54%) is the Tregonning granite, which underlies much of Cornish Tin’s exploration area.
“It is in the buried eastern slopes of this G5 granite that Cornish Tin has discovered a lithium field, and also high grade tin.”
Assays so far include discovery of two aplite pegmatite sheets (G5 granite) known as the Newall formation, containing high grades of lithium oxide and multiple intercepts of the G5 granite roof complex at the top of the buried bulk G5 granite.
Bulk tonnage of G5 granite below roof complex has “significant widths”.
PHOENIX
Cornish Tin has also expanded its mineral rights from its original 1,500 to 17,000 acres within the total Crown Estate grants of more than 121,000 acres.
The Crown Estate previously granted Cornish Tin the rights to prospect for and extract gold and silver across more than 121,000 acres of Cornwall, equating to 14% of the county’s land mass.
One area includes The Great Wheal Vor area and the other is in East Cornwall which encompasses Cornish Tin’s new Phoenix project.
The Duchy of Cornwall has also separately granted to Cornish Tin two exploration licences for the other minerals within areas in both West Cornwall (Vor) and East Cornwall (Phoenix).
Phoenix comprises 24 former tin and copper producing mines on the eastern flanks of Bodmin Moor, including Phoenix United mine and East Phoenix mine.
Founder and chief executive Sally Norcross-Webb described Phoenix as a major win for the company in increasing its potential high grade tin assets.
“We remain primarily focused on high grade tin, and believe that the market outlook for tin represents an exciting opportunity for our shareholders.
“In addition, our hardrock lithium assets could also deliver significant value in the future.
“The lithium results so far include some very encouraging grades: we will advance our lithium exploration with a close eye on the lithium market outlook.”
Since January 2022, the company has drilled a combined 9,290m and raised just under £4.9 million.
AWARDS
In June, Cornish Tin also received the 2024 Discovery of the Year award at the UK Mining Conference in Cornwall.
The company’s chairman Clive Newall won the Lifetime Achievement award.