Standard Uranium Confirms Strong Radioactivity During Successful Exploration Program at the Corvo Uranium Project

Vancouver, British Columbia--(Newsfile Corp. - September 22, 2025) - Standard Uranium Ltd. (TSXV: STND) (OTCQB: STTDF) (FSE: 9SU0) ("Standard Uranium" or the "Company") is pleased to announce preliminary results from its 2025 exploration programs the Corvo Uranium Project ("Corvo", or the "Project"), currently under a three-year earn-in option agreement with Aventis Energy Inc. (CSE: AVE) ("Aventis") . From July 4 to July 16, 2025, the Company completed a detailed mapping and sampling program across historical uranium showings and zones of interest on the Project.

Highlights:

• Off-Scale** Radioactivity at Surface: Verification of strong radioactivity at the historical Manhattan showing with handheld scintillometer measurements >65,535 counts per second ("cps") at surface, in addition to 112 further occurrences of highly anomalous*** radioactivity up to 13,500 cps across the Project.
• Discovery of New Radioactive Showings: Scintillometer prospecting uncovered previously undocumented radioactive occurrences across the Project in favorable rock types for uranium and Rare Earth Element ("REE") mineralization.
• Favorable Uranium Host Rocks: Geological mapping along structural and electromagnetic ("EM") trends across the Project confirmed the presence of deformed and hydrothermally altered basement lithologies including metasedimentary, calc-silicate, and granitic rocks.
• Ongoing Exploration: An extensive ground gravity survey is being planned for Q4 2025, designed to identify density anomalies potentially representing hydrothermal alteration systems coincident with newly refined EM conductor trends across the Project. A diamond drill program is being planned for Q1 2026 to begin testing targets developed and ranked through the detailed programs executed in 2025.

"Confirming strong radioactivity at multiple historical uranium showings on the Project and discovering undocumented showings speaks to the prospectivity of the Corvo Project. In addition, taking new samples will allow us to confirm uranium grades and build a comprehensive understanding of controls on mineralization prior to our maiden drill program," said Sean Hillacre, President & VP Exploration of Standard Uranium. "We look forward to continuing to bolster our targeting strategy through further work programs planned on the Project in 2025."