26 June 2026

Guardian Metal Resources plc

('Guardian Metal' or the 'Company')

Pre-Feasibility Study Update and Notice of Investor Presentation

Guardian Metal Resources plc (NYSE.A: GMTL, LON: GMET, OTCQB: GMTLF), a strategic mineral exploration company focused on tungsten in Nevada, USA, will publish the results of its Pre-Feasibility Study ("PFS" or the "Study") for the Pilot Mountain Tungsten Project ("Pilot Mountain" or the "Project") on 30 June 2026. Completion of the PFS will mark a significant development milestone for the Project and an important step in the Company's strategy to develop the first new domestically mined U.S. tungsten operation in over 15 years. 

The PFS is being supported by a U.S. Department of War $6.2m Defense Production Act Title III Investment¹ in Guardian Metal's wholly owned subsidiary, Golden Metal Resources (USA) LLC, and is led by Guardian Metal's in-house team in collaboration with Samuel Engineering, Inc., and a group of specialist engineering and environmental firms.

Following the publication of the PFS results, Guardian Metal will host a live investor presentation via 6ix on 01 July 2026 at 11:00 ET / 16:00 BST to discuss the Study and provide an update on the Company's outlook, including next steps for the Project.

The presentation is open to all existing and potential shareholders. Questions may be submitted ahead of the event via the registration form or at any time during the event.

Investors can sign up to 6ix for free and register for Guardian Metal's presentation here: https://6ix.com/event/guardian-metal-resources-presents-pilot-mountain-pfs

^[1] Company announcement, U.S. Department of Defense Awards $6.2M to Golden Metal Resources for the Pilot Mountain Project, dated 23 July 2025
( https://polaris.brighterir.com/public/guardian_metal_resources/news/rns/story/wvm0n3w )

Forward Looking Statements

This announcement contains forward-looking statements relating to expected or anticipated future events and anticipated results that are forward-looking in nature, and, as a result, are subject to certain risks and uncertainties, including general economic, market and business conditions, competition for qualified staff, the regulatory process and actions, technical issues, new legislation, potential delays or changes in plans, uncertainties resulting from operating in a new political jurisdiction, uncertainties regarding the results of exploration, the timing and granting of prospecting rights, the timing and granting of regulatory and other third party consents and approvals, Guardian Metal's or any third party's ability to execute and implement future plans, and the occurrence of unexpected events.

Forward-looking statements are subject to risks and uncertainties, including those described in the Company's filings with the SEC. There can be no assurance that the acquired water rights or real property interests will ultimately support a future mining operation at Tempiute or that the Project will proceed to development or production. Guardian Metal undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required by law.

This announcement does not purport to be full or complete. No reliance may or should be placed by any person for any purpose on the information contained in this announcement or its accuracy, fairness or completeness. The information in this announcement is subject to change.

For further information visit www.guardianmetalresources.com or contact the following:

About Guardian Metal Resources 

Guardian Metal Resources PLC (NYSE.A: GMTL, LON:GMET, OTCQB:GMTLF) is a strategic mineral exploration company driving the revival of U.S. mined tungsten production and strengthening America's defense metal independence. The Company is advancing two co-flagship tungsten projects, Pilot Mountain, one of the largest undeveloped tungsten deposits in the U.S. and Tempiute, formerly America's largest producing tungsten operation, both located in Nevada, one of the top-rated mining jurisdictions in the United States.

In July 2025, the U.S. Department of War (DoW) under Title III of the Defense Production Act of 1950, as amended, invested US$6.2M in Golden Metal Resources (USA) LLC, a wholly-owned subsidiary of Guardian Metal Resources PLC, to support the Pilot Mountain PFS. The Company completed a U.S. listing on the NYSE American on March 20, 2026. 

Tungsten is a strategic metal critical to the defense, energy transition, technology, and industrial sectors. In the context of shifting geopolitical dynamics and tightening Chinese export restrictions, Guardian Metal is well positioned to play a leading role in re-establishing a secure, domestically mined U.S. supply chain for this vital defense metal.