Announcement PDF CORNISH METALS RETAINS DIGBEE ESG RATING OF A 26 October 2026 Cornish Metals plc (AIM: TIN) (“Cornish Metals” or the “Company”), a mineral exploration and development company focused on advancing its wholly owned and permitted South Crofty tin project (“South Crofty”) in Cornwall, United Kingdom, is pleased to announce that it has retained an overall A rating from Digbee ESG (“Digbee”) in its second annual independent sustainability assessment. Digbee is a mining-specific ESG disclosure framework. Each submission is scored by a team of accredited ESG experts against standardised criteria, on a scale from AAA to D. Cornish Metals achieved an A rating at both corporate level (range B to AAA) and for the South Crofty project (range CCC to AAA), giving an overall score of A with a range of CCC to AAA. The range shows how the score could move depending on how identified risks are managed. This year’s assessment was carried out against Digbee’s development-stage frameworks and is valid for 12 months from 11 August 2026. To read the full report, please visit: https://cornishmetals.com/sustainability/digbee/ Extracts from the Report: Sustainability governance has become more structured, supported by Board oversight, ESG KPIs within senior management and executive incentives, dedicated ESG budgets, a revised double materiality assessment and publication of the Company’s second Sustainability Report. The Mine Water Treatment Plant treated approximately 3.6 million cubic metres of mine water during 2025, with reported discharges complying with permit limits. Renewable sources accounted for 96% of total energy consumption in 2025, with on-site hydropower supplying the treatment plant. South Crofty is delivering tangible regional benefits. In 2025, 84% of employees were recruited from Cornwall and the Company spent £24.4 million with 516 suppliers, including 212 Cornish businesses. The underground mine design, reuse of existing infrastructure on predominantly brownfield land and planned paste backfill of tailings limit new land disturbance and remove the need for a permanent surface tailings facility. Digbee also identified areas where further work is needed as South Crofty moves into a more complex phase of development. These include independent assurance of sustainability data, the maturity of risk management systems and evidence of how controls perform in practice, and greater visibility of how closure and long-term water management obligations are provided for. The Company is reviewing these findings as part of its Sustainability Strategy. Don Turvey, CEO of Cornish Metals, commented: “Retaining an A rating in our second Digbee assessment is a useful independent check on the progress we have made over the past year. It comes as South Crofty moves from planning towards construction, and the level of scrutiny rightly increases as activity on site grows. I am encouraged that Digbee has recognised the strengthening of our governance and the benefits already reaching Cornwall through local employment and spending with Cornish businesses. “Digbee has also been clear about where we need to do more, including independent assurance of our data and the maturity of our risk management systems. Investors, regulators and the communities around South Crofty expect to see evidence, not only intent, and this process gives us a consistent way of measuring ourselves and improving year on year.” ABOUT CORNISH METALS Cornish Metals is a mineral exploration and development company that is advancing the South Crofty critical mineral project towards production. South Crofty: is a historical underground tin mine located in Cornwall, United Kingdom and benefits from existing mine infrastructure including multiple shafts that can be used for future operations; is the highest grade known tin Mineral Resource not in production with significant near-mine and regional Mineral Resource potential; is permitted to commence underground mining (valid to 2071), construct a new processing facility and for all necessary site infrastructure; is expected to produce approximately 4,700 tonnes of tin-in-concentrate annually in the first five years of full production at lowest-quartile all-in sustaining costs over an initial 14-year mine life; will be a low environmental impact underground mine with zero surface tailings; would be potentially the first primary producer of tin in Europe or North America. Tin is a Critical Mineral as defined by the UK, American, and Canadian governments as it is used in almost all electronic devices and electrical infrastructure. Approximately two-thirds of the tin mined today comes from China, Myanmar and Indonesia; benefits from strong local community, regional and national government support with a growing team of skilled people, local to Cornwall, and could generate over 300 direct jobs; is an opportunity for a secure domestic supply of tin in the UK supporting a low carbon economy. ENDS Engage with us directly at our investor hub. Sign up at: https://investors.cornishmetals.com/link/PdVZJe For additional information please contact: Cornish Metals Fawzi Hanano Emily Allhusen investors@cornishmetals.com info@cornishmetals.com Tel: +44 1209 715 777 SPAngel Corporate Finance LLP (Nominated Adviser) Charlie Bouverat Adam Cowl Ewan Leggat Tel: +44 203 470 0470 Berenberg (Joint Broker) Jennifer Lee Ivan Briechle Tel: +44 20 3753 3040 Peel Hunt (Joint Broker) Ross Allister David McKeown Tel: +44 20 7418 8900 BlytheRay (Financial PR) Tim Blythe Megan Ray Said Izagaren cornishmetals@blytheray.com Tel: +44 207 138 3204 Image Attachments image1