Mr. Keith Bodnarchuk reports

COSA COMMENCES AIRBORNE GEOPHYSICAL SURVEYS AT THE COSMO AND ORION URANIUM PROJECTS, ATHABASCA BASIN, SASKATCHEWAN

Airborne geophysical surveying has commenced at Cosa Resources Corp.'s 100-per-cent-owned Cosmo and Orion uranium projects. Cosa has engaged Geotech Ltd. to complete comprehensive coverage over these projects utilizing its exclusive industry-leading Z-axis tipper electromagnetic system (ZTEM).

Highlights

• Property-wide coverage at Cosmo will determine if prospective conductive basement stratigraphy is present; notably the potential extension of the Bell Lake structural corridor, believed to host east-west structures critical in the formation of the Hurricane deposit to the east.
• Surveying at Orion will complete ZTEM coverage along the interpreted extension of the Larocque Lake trend which hosts the Hurricane deposit to the northeast.
• Detailed interpretation to identify follow-up target areas potentially related to structures and/or hydrothermal alteration to follow.

Details

Cosa has engaged Geotech to complete 618 line kilometres of ZTEM surveying at the Cosmo and Orion projects. Exclusive to Geotech, the ZTEM system is widely used within the Athabasca basin as it boasts a demonstrated industry leading ability to provide a wide range of frequency measurements with high accuracy and resolution at depth. Condor Consulting Inc., recognized expert in the field of geophysical data processing and interpretation with extensive experience with both the ZTEM system and the Athabasca basin, has been retained to complete a detailed interpretation of the results.

The primary objective of surveying is to determine if basement conductive zones like those associated with all Tier 1 Athabasca uranium deposits are present. ZTEM also has potential to map zones of anomalous conductivity in the sandstone which may reflect zones of hydrothermal alteration related to significant basement structures.

Results of the survey and data inversion will guide follow-up work. The identification of basement conductive trends would likely warrant a combination of ambient noise tomography (ANT) surveying and ground-based electromagnetic (EM). The most prospective areas identified from these surveys will be prioritized for drill testing and added to Cosa's pipeline of compelling drill targets.

About Cosmo

Cosa's 100-per-cent-owned, 10,145-hectare Cosmo project is located 36 kilometres west of the Hurricane deposit and 58 kilometres north of the Cigar Lake mine. Cosmo covers 18 kilometres of magnetic low strike length located on the western flank of a magnetic high; magnetic lows on the northern, eastern and southern flanks of the magnetic high-bordering Cosmo host EM conductors and uranium occurrences. This includes the Bell Lake east-west structural corridor, which may be important in localizing mineralization at the Hurricane deposit to the east. Cosmo has never been covered with ZTEM, and historical exploration work is limited. No drilling is known to have been completed at Cosmo. The depth to the unconformity is estimated to be 600 to 750 metres.

About Orion

Orion is located 29 kilometres west of the Cigar Lake uranium mine and immediately east of Orano's Parker Lake project. The project covers approximately 25 kilometres of strike length of the interpreted extension of the Larocque Lake trend. Cosa has repeatedly expanded its 100-per-cent-owned, 20,255-hectare Orion project since initial acquisition in 2022 as the fertile Larocque Lake trend hosts numerous occurrences of high-grade mineralization to the northeast while the portion covered by Orion is highly underexplored.

Orion is on the interpreted western extension of the Cigar Lake-Tucker Lake trend where it intersects the Larocque Lake trend. Drilling on trend at Parker Lake has intersected broad zones of structural disruption in the sandstone with illitic hydrothermal alteration and anomalous uranium geochemistry, including 0.05 per cent U3O8 (triuranium octoxide) over 1.0 metres (932.4 to 933.4 metres) immediately above the unconformity in drill hole PAR-03. Basement intersections included graphitic lithologies and structures, indicating basement geology and sandstone alteration along trend is consistent with deposits in the region.

In 2023, MobileMT surveying completed by Cosa over the western portion of Orion-identified basement hosted conductive zones overlain by conductivity anomalies in the sandstone. Follow-up ANT surveying in 2024 identified several kilometre-scale sandstone-hosted low velocity anomalies which are interpreted to reflect prospective structures and/or alteration above conductive basement zones and are considered high-priority targets for additional follow-up (see Cosa's news release dated May 28, 2025).

About Cosa Resources Corp.

Cosa Resources is a Canadian uranium exploration company operating in Northern Saskatchewan. The portfolio comprises roughly 237,000 hectares across multiple 100-per-cent-owned and Cosa-operated joint venture projects in the Athabasca basin region, all of which are underexplored, and the majority reside within or adjacent to established uranium corridors.

In January of 2025, the company entered a transformative strategic collaboration with Denison Mines that has secured Cosa access into several additional highly prospective eastern Athabasca uranium exploration projects. As Cosa's largest shareholder, Denison gains exposure to Cosa's potential for exploration success and its pipeline of uranium projects.

Cosa's award-winning management team has a long record of success in Saskatchewan. In 2022, members of the Cosa team were awarded the AME Colin Spence Award for their previous involvement in discovering IsoEnergy's Hurricane deposit. Prior to Hurricane, Cosa personnel led teams or had integral roles in the discovery of Denison's Gryphon deposit and 92 Energy's GMZ zone and held key roles in the founding of both NexGen and IsoEnergy.

The company's core focus throughout 2025 is drilling at the Murphy Lake North joint venture. Murphy Lake North is a 70/30 joint venture between Cosa and Denison respectively and is located at the northern end of the Larocque Lake trend. The project is within three kilometres of and on trend with the Hurricane deposit. Initial drilling completed by Cosa during winter 2025 intersected broad zones of hydrothermal alteration of the sandstone, associated with prospective basement structures interpreted as the strike extension of those controlling the Hurricane deposit. An expanded follow-up campaign is currently in planning for the summer season.

Technical disclosure

Historical exploration results disclosed in this news release were sourced from the Saskatchewan Mineral Assessment Database (SMAD). These results have not been verified by the qualified person except as noted below and are relied upon for qualitative assessment of the project only. At present, the company does not intend to complete additional verification of historical results. SMAD sources for Orion include MAW02291, MAW02121, MAW00736, 74I04-0010, 74I04-0009, 74I03-0015, 74I03-0013 and 74I02-0073. SMAD sources for Cosmo include 74I-0010, 74I-0012 and 74I10-0020.

Verification of historical drilling results included confirming the approximate collar location of historical drill holes from air photos and reviewing core photos and geochemical results. Core photos were not available for all drill holes. Cosa intends to relog drill core from the two historical drill holes Orion in the summer of 2025. Verification of geophysical results is limited to reviewing historical interpretations of ground surveys and confirming selected survey grid locations from air photos.

Qualified person

The company's disclosure of technical or scientific information in this press release has been reviewed and approved by Andy Carmichael, PGeo, vice-president, exploration, for Cosa. Mr. Carmichael is a qualified person as defined under the terms of National Instrument 43-101. This news release refers to neighbouring properties in which the company has no interest. Mineralization on those neighbouring properties does not necessarily indicate mineralization on the company's properties.

We seek Safe Harbor.