Standard Uranium Generates New High-Priority Uranium Targets at Flagship Davidson River Project Following Exosphere Multiphysics Surveys

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Vancouver, British Columbia--(Newsfile Corp. - August 21, 2025) - Standard Uranium Ltd. (TSXV: STND) (OTCQB: STTDF) (FSE: 9SU0) ("Standard Uranium" or the "Company") is pleased to provide an update on its summer exploration programs at the Davidson River Project ("Davidson River" or the "Project") in the southwest Athabasca Basin region, northern Saskatchewan (Figure 1). The Company has successfully completed the first ExoSphere Multiphysics surveys in the southwest Athabasca uranium district on Davidson River, outlining multiple highly prospective target areas across the Warrior, Bronco, and Thunderbird conductor corridors.

Highlights:

• Successful ExoSphere Multiphysics Surveys: Combined 3D Ambient Noise Tomography ("ANT") and Horizontal-to-Vertical Spectral Ratio ("HVSR") velocity models and constrained ground gravity block models have been generated on the Warrior, Bronco, and Thunderbird trends (Figure 2), providing critical subsurface information for guiding ongoing exploration across the Project.

• Critical Vectors for High-Grade^* Uranium: Distinct gravity-low anomalies representing potential hydrothermal alteration zones have been identified across all three surveyed structural corridors, overlapping known electromagnetic ("EM") conductors, extrapolated basement faults from previous drilling, and basement velocity lows marking structural disruption and/or favorable lithological contrasts (Figure 3). Multiple new targets also coincide with defined EM SmartMatch targets provided by ALS GoldSpot based on machine learning anomaly matching to the Arrow and Triple R deposits.

• Fall 2025 Drill Program: The Company has secured drilling permits and executed Exploration Agreements with its Clearwater River Dene Nation ("CRDN") partners. With vendors now in place, the Company is planning a four-to-six-week drill program scheduled to commence in early September 2025.

Sean Hillacre, President & VP Exploration of Standard Uranium, commented, "We have a clear geoscientific recipe for discovery at Davidson River leveraging exploration techniques and success next door at the Arrow and Triple R uranium deposits. The new datasets from our Multiphysics surveys unlock invaluable targeting information at Davidson River with the addition of gravity and seismic data outlining potential areas of significant hydrothermal alteration, akin to the geophysical signatures of nearby high-grade deposits in the same geological domain. The technical team and I are very excited to get the drills into the ground to test these new targets after several years of integrative targeting efforts."

Figure 1. Overview of Standard Uranium's Flagship Davidson River Project in the southwest Athabasca Basin uranium district along trend from significant uranium discoveries and resources^1,2.

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https://images.newsfilecorp.com/files/10633/263277_5323228814a8b999_001full.jpg

Figure 2. Summary map showing major EM conductor trends on Davidson River and completed ExoSphere Multiphysics grid locations, with first vertical derivative magnetics in the background.

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2025 Drill Program – Integrative Targeting

ANT + HVSR + Gravity grids covering uranium-bearing structural corridors on the Project were designed to characterize lithological variations and alteration signatures, in addition to further refining the structural architecture of known basement conductors on Davidson River. The surveys have been completed, providing detailed data on subsurface features and enhancing the understanding of the geological framework in the area.

Along each of the Warrior, Bronco, and Thunderbird conductive trends, multiple gravity-low anomalies have been identified from constrained density models (Figure 3). These anomalies overlap with known EM conductors, extrapolated oriented core shearing/faulting, and abrupt ANT-HVSR velocity anomalies that may represent basement wedges or vertically offset faulting, typical structural traps for uranium mineralization. Additionally, where these potential structures intersect gravity-low anomalies, they may indicate structurally focused hydrothermal alteration, such as clay replacement, which is commonly associated with basement-hosted uranium mineralization. The intersection of these geophysical anomalies with modeled graphitic shear zones results in multiple highly prospective drill target areas.

Figure 3. Results of Multiphysics surveys on the Warrior, Bronco, and Thunderbird corridors, highlighting integrated target areas – EM conductors, cross-faults, gravity lows, and velocity lows.

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Fall 2025 Diamond Drill Program

The Company has completed comprehensive analysis and integration of survey data and plans to execute a diamond drilling program to test high-priority targets generated from the Multiphysics survey results. This 2025 diamond drill program marks the Project's first drilling campaign since 2022.

Drill targets will be prioritized based on integration of positive results from previous drilling, new ANT + HVSR + Gravity anomalies, as well as ALS machine learning SmartMatch targets. The Company has received processed high-confidence datasets from all three survey grids through joint inversion and modeling, resulting in optimized drill targeting for the September 2025 program.

About Davidson River

Davidson River is Standard Uranium's flagship property, located in the southwest Athabasca Uranium District of the Athabasca Basin, Saskatchewan, and encapsulates the inferred extension of the structural trend that hosts the Triple R and Arrow uranium deposits (Figure 1). The Project consists of 10 contiguous mineral dispositions and lies approximately 25 to 30 km west of Arrow and Triple R and 75 km south of the past-producing Cluff Lake uranium mines. The Company has completed 16,561 metres of diamond drilling in 39 drill holes on the Davidson River property since 2020, which has further refined the exploration strategy for high-grade basement hosted uranium mineralization on the property³.

Davidson River hosts four main conductive corridors – the Warrior, Bronco, Thunderbird, and Saint trends (Figure 2). These conductive trends are associated with graphitic-sulphidic structures in basement rocks, which are commonly associated with high-grade^* uranium systems, providing the conduits for mineralizing fluids. This concept has been proven for all four corridors, with several instances of graphitic-sulphidic fault rocks and reactivated structures intersected along the tested strike length.

Favorable basement rock types and alteration phases have been observed across the strike length of the main trends, resembling those which host other uranium deposits in the southwestern Athabasca Basin region. Key indicators include clay-dravite alteration and stacked lenses of variably strained graphite and sulphide-bearing garnetiferous gneisses and altered feldspar-rich rocks. Structural zones in the basement are locally associated with elevated uranium and/or boron values (over 1,000 ppm B), such as in DR-20-009 and -011³.

The results from diamond drilling programs to date highlight the potential for the Davidson River Project to host significant basement hosted unconformity-related uranium mineralization, and the property contains several priority targets along all four trends that warrant further exploration.

*The Company considers uranium mineralization with concentrations greater than 1.0 wt% U₃O₈ to be "high-grade"

Qualified Person Statement

The scientific and technical information contained in this news release has been reviewed, verified, and approved by Sean Hillacre, P.Geo., President and VP Exploration of the Company and a "qualified person" as defined in NI 43-101.

Historical data disclosed in this news release relating to sampling results from previous operators are historical in nature. Neither the Company nor a qualified person has yet verified this data and therefore investors should not place undue reliance on such data. The Company's future exploration work may include verification of the data. The Company considers historical results to be relevant as an exploration guide and to assess the mineralization as well as economic potential of exploration projects. Any historical grab samples disclosed are selected samples and may not represent true underlying mineralization.

References

¹ Arrow deposit, Rook I Project, Saskatchewan, NI 43-101 Technical Report on Feasibility Study, Prepared for NexGen Energy Ltd., Effective date: February 22, 2021
² Feasibility Study, NI 43-101 Technical Report, for PLS Property, Prepared for Fission Uranium Corp., Effective date: January 17, 2023
³ Davidson River Project Overview, https://standarduranium.ca/projects/davidson-river-project

Private Placement Update

The Company also confirms that is continuing to move forward with its previously announced non-brokered private placement (the "Offering") to raise gross proceeds of up to C$3,500,000 and expects to complete an initial tranche of the Offering shortly.

The Offering consists of units of the Company (each, a "Unit") at a price of C$0.08 per Unit, and flow-through units of the Company (each, a "FT Unit", and collectively with the Units, the "Offered Securities") at a price of C$0.10 per FT Unit. Each Unit consists of one common share of the Company (each a "Unit Share") and one-half of one common share purchase warrant (each whole warrant, a "Warrant"). Each FT Unit will consist of one common share of the Company to be issued as a "flow-through share" within the meaning of the Income Tax Act (Canada) (each, a "FT Share") and one-half of one Warrant. Each whole Warrant entitles the holder to purchase one common share of the Company (each, a "Warrant Share") at a price of C$0.15 at any time on or before that date which is twenty-four months after the closing date of the Offering.

The Units will be offered to "accredited investors", as well as existing shareholders of the Company resident in British Columbia under British Columbia Instrument 45-534 – Exemption from Prospectus Requirement for Certain Trades to Existing Security Holders (the "Existing Shareholder Exemption").

Only those shareholders who are resident in British Columbia and hold shares of the Company as of August 19, 2025 (the "Record Date") are eligible to participate under the Existing Shareholder Exemption. Any person who becomes a shareholder of the Company after the Record Date is not permitted to participate under the Existing Shareholder Exemption. Existing shareholders who are interested in participating in the Offering should contact the Company at the contact information set out in this press release.

Subscriptions pursuant to the Existing Shareholder Exemption are being allocated to subscribers on a "first come, first served" basis wherein the subscribers who are first to submit a completed subscription agreement and payment of the corresponding subscription proceeds will be accepted up until the maximum amount of the Offering is reached.

There are conditions and restrictions when relying upon the Existing Shareholder Exemption; namely, the subscriber must: a) be a shareholder of the Company on the Record Date (and still is a shareholder); b) be purchasing the units as a principal, that is, for their own account and not for any other party; and c) may not purchase more than $15,000 value of securities from the Company in any 12-month period, unless they have first received suitability advice from a registered investment dealer, and, in this case, subscribers will be asked to confirm the registered investment dealer's identity and employer.

The Company intends to use the proceeds of the Offering for the exploration and development of its projects and for general corporate and working capital purposes. The actual allocation of the proceeds may vary though, depending on future operations or unforeseen events or opportunities. If the Offering is not fully subscribed, the Company may apply the proceeds of the Offering in such priority and proportions as the board of directors of the Company determines to be in the best interests of Company.

About Standard Uranium (TSXV: STND)

We find the fuel to power a clean energy future

Standard Uranium is a uranium exploration company and emerging project generator poised for discovery in the world's richest uranium district. The Company holds interest in over 233,254 acres (94,394 hectares) in the world-class Athabasca Basin in Saskatchewan, Canada. Since its establishment, Standard Uranium has focused on the identification, acquisition, and exploration of Athabasca-style uranium targets with a view to discovery and future development.

Standard Uranium's Davidson River Project, in the southwest part of the Athabasca Basin, Saskatchewan, comprises ten mineral claims over 30,737 hectares. Davidson River is highly prospective for basement-hosted uranium deposits due to its location along trend from recent high-grade uranium discoveries. However, owing to the large project size with multiple targets, it remains broadly under-tested by drilling. Recent intersections of wide, structurally deformed and strongly altered shear zones provide significant confidence in the exploration model and future success is expected.

Standard Uranium's eastern Athabasca projects comprise over 42,303 hectares of prospective land holdings. The eastern basin projects are highly prospective for unconformity related and/or basement hosted uranium deposits based on historical uranium occurrences, recently identified geophysical anomalies, and location along trend from several high-grade uranium discoveries.

Standard Uranium's Sun Dog project, in the northwest part of the Athabasca Basin, Saskatchewan, is comprised of nine mineral claims over 19,603 hectares. The Sun Dog project is highly prospective for basement and unconformity hosted uranium deposits yet remains largely untested by sufficient drilling despite its location proximal to uranium discoveries in the area.

Cautionary Statement Regarding Forward-Looking Statements

This news release contains "forward-looking statements" or "forward-looking information" (collectively, "forward-looking statements") within the meaning of applicable securities legislation. All statements, other than statements of historical fact, are forward-looking statements and are based on expectations, estimates and projections as of the date of this news release. Forward-looking statements include, but are not limited to, statements regarding: the timing and content of upcoming work programs; geological interpretations; timing of the Company's exploration programs; and estimates of market conditions.

Forward-looking statements are subject to a variety of known and unknown risks, uncertainties and other factors that could cause actual events or results to differ from those expressed or implied by forward-looking statements contained herein. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Certain important factors that could cause actual results, performance or achievements to differ materially from those in the forward-looking statements are highlighted in the "Risks and Uncertainties" in the Company's management discussion and analysis for the fiscal year ended April 30, 2024.

Forward-looking statements are based upon a number of estimates and assumptions that, while considered reasonable by the Company at this time, are inherently subject to significant business, economic and competitive uncertainties and contingencies that may cause the Company's actual financial results, performance, or achievements to be materially different from those expressed or implied herein. Some of the material factors or assumptions used to develop forward-looking statements include, without limitation: that the transaction with the Optionee will proceed as planned; the future price of uranium; anticipated costs and the Company's ability to raise additional capital if and when necessary; volatility in the market price of the Company's securities; future sales of the Company's securities; the Company's ability to carry on exploration and development activities; the success of exploration, development and operations activities; the timing and results of drilling programs; the discovery of mineral resources on the Company's mineral properties; the costs of operating and exploration expenditures; the presence of laws and regulations that may impose restrictions on mining; employee relations; relationships with and claims by local communities and indigenous populations; availability of increasing costs associated with mining inputs and labour; the speculative nature of mineral exploration and development (including the risks of obtaining necessary licenses, permits and approvals from government authorities); uncertainties related to title to mineral properties; assessments by taxation authorities; fluctuations in general macroeconomic conditions.

The forward-looking statements contained in this news release are expressly qualified by this cautionary statement. Any forward-looking statements and the assumptions made with respect thereto are made as of the date of this news release and, accordingly, are subject to change after such date. The Company disclaims any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required by applicable securities laws. There can be no assurance that forward-looking statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements.

Neither the TSX-V nor its Regulation Services Provider (as that term is defined in the policies of the TSX-V) accepts responsibility for the adequacy or accuracy of this release.

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