(MENAFN- Newsfile Corp) Vancouver, British Columbia--(Newsfile Corp. - December 4, 2025) - Myriad Uranium Corp. (CSE: M) (OTCQB: MYRUF) (FSE: C3Q) (" Myriad " or the " Company ") is pleased to announce that it has just completed a large-scale helicopter-borne radiometric and magnetic survey across the entire Copper Mountain Uranium Project.

Myriad's CEO Thomas Lamb commented: "We are very pleased to have completed this helicopter-borne radiometric survey across the entire Copper Mountain project ahead of winter. This survey has been planned for some time and is a key step in understanding the wider potential of the entire project and indeed the district, and the knowledge gained will substantially strengthen our exploration and development programs.

Our extensive proprietary historical data set, along with recently obtained documents-including the comprehensive 1982 Bendix study, which assessed the broader district's contained uranium at ~655 Mlbs and a smaller area (the so-called "Contral Area", of which Myriad controls at least 70%) at ~245 Mlbs-confirms that several highly prospective areas at Copper Mountain were historically underexplored simply because they were difficult to access. This survey, particularly the radiometric survey, will illuminate those areas in a way that was never previously possible and allow us to understand and test the Bendix findings in a meaningful way. (Note these are not NI 43-101 category estimates. See the Company's recent press release here and also the section on historical estimates below). In addition, once processed, these surveys will be extremely useful as we refine targets for our next phase of drilling which we will launch as soon as possible during 2026."

Geophysical Survey Parameters

The geophysical survey was completed by Precision Geosurveys, based out of Reno, Nevada, using an Airbus AS350 helicopter. The survey area covered an extent of approximately 191.8 km², with a total of 2,114 line-kilometres completed at 100 m line spacing and with 1,000 m tie lines at a flying height of 30 m in a north-south orientation.

Magnetic data was collected using a Scintrex CS-3 (or Geometrics equivalent) cesium vapor airborne magnetometer sensor; sensitivity better than 0.01 nT and sampling rate of 20 Hz providing sample spacings of 1-2 meters, in a nose mounted stinger configuration with 3-axis real-time compensation. Two or more base station magnetometers with integrated GPS time synchronization were used for correction of temporal magnetic variations. Radiometric data was collected using a Medusa gamma spectrometer system: 21 litres of proprietary self-calibrating NaI(Tl) gamma radiation detection crystals with 512 channel output at 1 Hz sampling rate. Position control was achieved using a WAAS-enabled GPS navigation system integrated with pilot steering display and data logger. In good weather conditions, flight line accuracy of +/-8 m from desired track was achieved. Elevation control was achieved using an Opti-Logic laser altimeter (or equivalent) and height-above-ground pilot display and recording.

Preliminary uncorrected magnetic and radiometric images have been received, while final processed data and outputs are expected in January 2026.

Historical Estimates

The estimates discussed in this news release are historical in nature and do not represent current mineral resource, reserve or exploration target estimates under the category definitions provided by NI 43-101. They represent potential mineral endowments that would require exploration work and drilling to verify. The key assumptions, parameters, and methods used to prepare the historical estimates are described in a previous news release, available here. There are no more recent estimates of this type. A qualified person has not done sufficient work to classify the historical estimates as current mineral resources or mineral reserves. Myriad is not treating the historical estimates as current mineral resources or mineral reserves.

Qualified Person and Data Verification

The scientific or technical information in this news release respecting the Company's Copper Mountain Project has been reviewed and approved by George van der Walt, MSc., Sci., FGSSA, Myriad's consulting geologist and a Qualified Person as defined in National Instrument 43-101 - Standards of Disclosure for Mineral Projects. While the content of the reports is considered to be relevant and reliable, the underlying data, such as original drill logs, sampling, analytical and test data certificates, quality assurance and quality control, is not available for verification. Further work, such as drilling and sampling, will be required to verify or create supplementary information to support the underlying assumptions and conclusions.

About Myriad Uranium Corp.

Myriad Uranium Corp. is a uranium exploration company which has met its obligations to earn a 75% interest in the Copper Mountain Uranium Project in Wyoming, USA. Copper Mountain hosts several known uranium deposits and historic uranium mines, including the Arrowhead Mine which produced 500,000 lbs U3O8. Copper Mountain saw extensive drilling and development by Union Pacific during the late 1970s including the development of a mine plan to fuel a planned fleet of California Edison reactors. Operations ceased in 1980 before mining could commence due to falling uranium prices. Approximately 2,000 boreholes have been drilled at Copper Mountain, and the Project Area has significant exploration upside. Union Pacific is estimated to have spent C$117 million (2024 dollars) exploring and developing Copper Mountain, generating significant historical resource estimates. The Company also holds a 100% interest in the Red Basin Uranium Project in New Mexico, which has a near-surface mineralisation, with significant upside potential. Our Crux Investor overview page including recent interviews can be viewed here. The Company's presentation can be viewed here. News releases regarding historical drilling can be viewed here and here. The final news release regarding chemical assays of 2024 Copper Mountain drilling can be viewed here. A news release detailing a comprehensive assessment of Copper Mountain's uranium endowment by Bendix Engineering for the US Department of Energy published in 1982 can be viewed here.

For further information, please refer to Myriad's disclosure record on SEDAR+ ( ), contact Myriad by telephone at +1.604.418.2877, or refer to Myriad's website at .

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