IsoEnergy-Purepoint Joint Venture Delivers High-Grade Uranium Results at Dorado Project

• IsoEnergy and Purepoint intersected 8.1% U₃O₈ over 0.4 metres within a broader 2.1-metre interval grading 1.6% U₃O₈ at the Nova discovery zone.
• The summer drill program completed 5,030 metres across 11 holes before wildfires forced early termination of the planned 5,400-metre program.
• Additional drilling results from Serin and Turaco targets provided valuable calibration data for the project's geophysical model.
• The Dorado Project encompasses over 98,000 hectares of prime uranium exploration ground in Saskatchewan's Athabasca Basin.
• Follow-up drilling programs are planned for early 2026 pending complete assay results and geological interpretation.

IsoEnergy Ltd. (NYSE American: ISOU | TSX: ISO) operates as a uranium exploration and development company focused on high-grade uranium deposits in Saskatchewan's Athabasca Basin. The company maintains a 50/50 joint venture partnership with Purepoint Uranium Group Inc. (TSXV: PTU | OTC: PTUUF) across multiple uranium exploration projects, including the flagship Dorado Project. This partnership provides investors with exposure to one of the world's premier uranium exploration regions through a diversified portfolio of properties totaling over 98,000 hectares of exploration ground.

Significant High-Grade Uranium Intersections

The latest drilling results from the Nova discovery zone represent the most significant assay intervals reported to date from the Dorado Project. Drill hole PG25-07A delivered exceptional grades, intersecting 2.1 metres at 1.6% U₃O₈, with a high-grade core of 0.4 metres at 8.1% U₃O₈. The same hole also returned an additional 4.9 metres at 0.52% U₃O₈, including 0.4 metres at 2.9% U₃O₈.  Chris Frostad, President and CEO of Purepoint Uranium stated:

"Eight percent uranium is an excellent grade from the centre of the very strong radioactive interval drilled by hole 7A. These assays reinforce the strength of this newly discovered system and provide a solid anchor point as we continue to test the mineralized structure in all directions."

The Nova discovery zone continues to demonstrate consistent uranium mineralization across multiple drill holes. Previous results from the area include PG25-05, which intersected 1.0 metre at 2.19% U₃O₈, including 0.3 metres at 5.38% U₃O₈. These results establish a pattern of high-grade uranium occurrences within a defined geological structure.

2025 Drill Program Operations

The summer 2025 drill program achieved substantial progress despite facing operational challenges from regional wildfires. The companies completed 5,030 metres of drilling across 11 holes, representing 93% of the planned 5,400-metre program. The program focused on three primary target areas: Nova discovery zone, Turaco Grid, and Serin Grid.

At the Turaco Grid, two holes totaling 832 metres targeted parallel airborne electromagnetic conductors within Zone 3. While these holes did not encounter anomalous radioactivity, with the highest reading reaching 578 CPS, the results provide valuable calibration data for the project's updated geophysical model.

Drilling at the Serin Grid included two holes totaling 1,032 metres. SL25-11 intersected anomalous radioactivity hosted by a 6-metre-wide chloritized pegmatite, returning readings up to 1,200 CPS from the downhole gamma probe. These results offer insights into basement geology and structural context that will guide future exploration targeting.

Regional wildfires ultimately forced the early termination of the program, limiting helicopter access and creating hazardous field conditions. The challenging conditions also led to the deferral of planned drilling at the nearby Celeste project, another joint venture between IsoEnergy and Purepoint.

Technical Analysis & Methodology

The drilling program employed industry-standard techniques for uranium exploration in the Athabasca Basin. Core samples underwent analysis at Saskatchewan Research Council Geoanalytical Laboratories, an ISO/IEC 17025:2005 accredited facility independent of both companies. The laboratory utilized partial and total digestion methods with inductively coupled plasma mass spectroscopy and optical emission spectroscopy for multi-element analysis.

A Mount Sopris 2PGA-1000 downhole total gamma probe provided radiometric surveying capabilities during drilling operations. All reported drill intercepts represent core width measurements, with true thickness determinations pending further geological interpretation.

The analytical process includes comprehensive quality assurance and quality control measures, incorporating blanks, duplicate sample comparisons, and standard sample variance analysis. U₃O₈ percentage values derive from uranium-total results measured through total digestion preparation followed by ICP-OES analysis, with conversion factors applied to standard reporting formats.

Geological Context & Resource Potential

The Dorado Project occupies a strategic position on the southeastern margin of Saskatchewan's Athabasca Basin, one of the world's premier uranium districts. The project area encompasses the former Turnor Lake, Geiger, Edge, and Full Moon properties, all characterized by graphite-bearing lithologies and fault structures favorable for uranium deposition.

Shallow unconformity depths across the property typically range between 30 and 300 metres, enabling highly efficient drilling operations and rapid follow-up on exploration results. This geological advantage reduces operational costs and accelerates the pace of exploration compared to deeper basement targets.

Recent drilling activities by IsoEnergy east of the Hurricane Deposit have intersected strongly elevated radioactivity across multiple holes, confirming the continuity of the fertile graphitic rock package. These results highlight the broader regional potential for additional high-grade uranium discoveries across the joint venture's extensive land position.

Strategic Positioning & Market Context

The joint venture structure between IsoEnergy and Purepoint provides both companies with exposure to multiple high-potential uranium exploration properties while sharing operational costs and technical expertise. The partnership encompasses more than 98,000 hectares of exploration ground, representing one of the largest uranium exploration land packages in the Athabasca Basin.

Saskatchewan's Athabasca Basin hosts some of the world's highest-grade uranium deposits, with several operating mines and advanced development projects in the region. The basin's established infrastructure, favorable mining jurisdiction, and proven geological potential make it a preferred destination for uranium exploration investment.

The timing of these exploration results coincides with growing global interest in uranium as nuclear energy gains recognition as a clean baseload power source. Increased uranium demand projections and limited new supply development have created a favorable market environment for exploration companies with high-quality assets.

Future Development Plans

The companies are currently awaiting complete geochemical assays and structural interpretations from the 2025 drill program. These results will inform detailed planning for follow-up drilling scheduled for early 2026, with programs focused on expanding the Nova discovery and testing priority corridors across the broader Dorado Project property.

The comprehensive dataset from the 2025 program, including geophysical calibration data from the Turaco and Serin grids, will enable more targeted exploration approaches in future drilling campaigns. The companies plan to integrate geological, geochemical, and geophysical data to optimize drill hole placement and maximize the potential for additional high-grade discoveries.

The deferral of the Celeste project drilling provides an opportunity to incorporate lessons learned from the Dorado program and potentially enhance exploration efficiency when operations resume. The companies maintain budget and schedule flexibility to adapt their exploration strategies based on evolving market conditions and technical results.

For Investors

For investors evaluating IsoEnergy, the latest drilling results at the Dorado Project demonstrate the company's ability to identify and develop high-grade uranium targets in one of the world's premier uranium districts. The 8.1% U₃O₈ intersection represents exceptional grade material that could support future resource development, while the broader mineralized system suggests potential for expansion through continued exploration.

The joint venture structure provides IsoEnergy with cost-effective exposure to extensive exploration acreage while maintaining operational flexibility through shared technical expertise and financial resources. The company's focus on the Athabasca Basin positions it within an established uranium mining jurisdiction with proven geological potential and supportive infrastructure.

However, investors should consider the early-stage nature of the exploration program and the inherent risks associated with mineral exploration activities. The successful development of uranium resources requires sustained exploration investment, favorable market conditions, and eventual permitting and development capital. The impact of operational challenges, such as the wildfire disruptions experienced in 2025, demonstrates the potential for external factors to influence exploration timelines and costs.

The pending release of complete assay results and geological interpretation will provide additional data points for evaluating the Nova discovery's resource potential and the broader project's exploration upside. The planned 2026 drilling programs represent the next critical phase in advancing the project toward potential resource definition and development consideration.