The information contained within this announcement was deemed by the Company to constitute inside information as stipulated under the UK Market Abuse Regulation.

14 September 2026

ECR MINERALS PLC

("ECR Minerals", "ECR" or the "Company")

Maddens Decline Development Advances Towards Production

ECR Minerals plc (LON: ECR), the exploration and development company focused on gold in Australia, is pleased to announce that development drilling and blasting is now underway on the main decline (the downwards tunnel to access the ore body) at the Maddens Underground Mine in North Queensland, marking an important step in the Company's programme to commence gold production from Maddens during Q4 2026.  ECR has a 50% interest in the Maddens Flat Group of Mines.

The commencement of decline advancement follows a significant programme of underground enabling works, including upgrades to mine ventilation, establishment of escapeways, surveying and preparation of underground equipment. In parallel, refurbishment of the existing processing plant is progressing, including installation of a 20-inch Knelson concentrator.

Highlights

·      Development drilling and blasting is now underway on the main decline of the Maddens Underground Mine from the 355m level.

·      Maddens has entered its next phase of underground development, following significant work already completed on ventilation, underground safety and access, surveys and equipment preparation.

·      Decline advancement of approximately 72.5m is targeting the development of an ore drive with approximately 12.5m of stoping height ("backs"), which is believed to contain an estimated potential of 1,500 oz Au.

·      Processing plant refurbishment advancing in parallel, including installation of a 20-inch Knelson concentrator to optimise gold recovery.

·      First ore processing from existing surface stockpiles is currently expected by the end of September 2026.

·      Gold production from newly accessed underground ore targeted during Q4 2026, as development advances towards the planned intersection with the Maddens Reef.

·      The current programme is intended to be an important step in establishing Maddens as a producing hard-rock gold operation within the wider Maddens Flat Group of Mines.

Background

Recent work at the Maddens Underground Mine has focused on upgrading the mine ventilation system, establishing escapeways from the decline face to surface, and conducting surveys and equipment preparation to enable decline advancement. From the 355m level, the decline is to advance 15m to the north-east, curve southwards for a 180-degree turn, and advance 37.5m south-west to a planned intersection of the Maddens Reef at approximately 342m (see Fig. 1). Some 12.5m of stoping height ("backs") is expected to be developed, containing an estimated potential of 1,500 oz of gold.

Fig 1. Maddens Mine viewed from the southwest. Note only accessible stopes surveyed.

Processing plant refurbishments are underway, including the installation of a 20-inch Knelson concentrator to optimise gold recovery. The first ore processing from existing surface stockpiles is expected by the end of September 2026.

ECR Non-Executive Director Mike Parker commented: "With the ventilation upgrade completed and the key underground enabling work now in place, Maddens has moved into an important new phase. Development drilling and blasting on the main decline is underway, with the focus now firmly on advancing towards the next area of production ore.

"The planned decline development is designed to provide access to an ore drive with approximately 12.5 metres of stoping height and an estimated potential of 1,500 ounces of gold. Importantly, this work is being undertaken within an existing underground mine with established infrastructure, an experienced operating team and a processing plant already on site.

"Plant refurbishment is also progressing in parallel, including installation of the 20-inch Knelson concentrator. Our objective is to bring newly mined underground ore into production during Q4 2026, and I am very encouraged by the progress being made on site."

ECR Chairman Nick Tulloch added: "Having visited the Maddens mine in recent days, it is clear that the team has made significant progress in advancing production capabilities across both the underground mine and the processing plant. Considerable work has already been completed on ventilation, rock bolting and escapeways, and we are now seeing that preparation translate into active decline development.

"We are excited to see the fruition of this hard work, with the mine advancing well and plant refurbishments underway that will enable ECR to report its maiden production from Maddens in the coming months. The next major objective is to access the planned production area through the decline, with production from newly mined underground ore targeted during Q4 2026.

"Maddens is an important part of the wider Maddens Flat Group of Mines and we are very encouraged by the progress being made on site. I would like to thank the team for their continued efforts and dedication."

Review of Announcement by Qualified Person

This announcement has been reviewed by Michael Parker, Non-Executive Director of ECR Minerals Plc. Michael Parker has a BSc. in Mining Geology and is a professional geologist and is a Fellow of the Australasian Institute of Mining and Metallurgy (FAusIMM). He is a qualified person as defined by the AIM Note for Mining, Oil and Gas Companies.

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ABOUT ECR MINERALS PLC

ECR Minerals is a mineral exploration and development company operating through four wholly owned Australian subsidiaries ECR Minerals (Australia) Pty Ltd ("ECR Australia"), ECR Minerals (Queensland) Pty Ltd ("ECR Queensland"), ECR Minerals (Raglan) Pty Ltd ("ECR Raglan") and ECR Minerals (Paleogold) Ltd ("ECR Paleogold").

ECR Paleogold has a 50% interest in the Maddens hard rock mining project in Northern Queensland where work is underway for production this year.  It also has a 20% interest in the Salt Bush shallow open cut mining project in South Australia where preparations are underway for production which is expected to commence around mid-2027.  ECR Paleogold also owns 80% of the Tuckanarra exploration project in Western Australia.

ECR Australia owns the Bailieston and Creswick gold projects in central Victoria, Australia as well as the Tambo gold project in eastern Victoria.

ECR Raglan has a mining lease at the Raglan alluvial gold project in central Queensland, Australia and ECR Queensland has two approved exploration permits over the nearby Blue Mountain alluvial gold project.   ECR is currently working to bring the Blue Mountain alluvial gold project into production.  ECR Queensland also has three approved exploration permits covering 946 km² over a relatively unexplored area in Lolworth Range in northern Queensland. Furthermore, it has also submitted a licence application at Kondaparinga which is approximately 120km² in area and located within the Hodgkinson Gold Province, 80km NW of Mareeba, North Queensland.

Following the sale of the Avoca, Moormbool and Timor gold projects in Victoria, Australia to Fosterville South Exploration Ltd (TSX-V: FSX) and the subsequent spin-out of the Avoca and Timor projects to Leviathan Gold Ltd (TSX-V: LVX), ECR Australia has the right to receive up to A$2 million in payments subject to future resource estimation or production from these projects. 

ECR Australia also has approximately A$77 million of unutilised tax losses incurred during previous operations.