F3 Uranium Extends Tetra Zone Mineralisation to 135 Metres

• Fall 2025 drilling extended the Tetra Zone's interpreted mineralised plunge length from 60 metres to 135 metres, a 125% increase.
• Five diamond drill holes totalling 2,628 metres tested plunge continuity, with hole PLN25-221 stepping out approximately 28 metres from previous drilling.
• Hole PLN25-217 intersected 29.5 metres of mineralisation, including 27.5 metres continuous, with 2.30 metres exceeding 10,000 counts per second between 396.70 metres and 407.30 metres depth.
• Approximately 300 metres of shear zone remains untested in the up-plunge direction towards the Athabasca Unconformity, with down-plunge targets also identified.
• Assay results from the fall programme are currently being processed at SRC Geoanalytical Laboratories, with follow-up drilling planned to commence later this month.

F3 Uranium Corp. (TSXV: FUU) (OTCQB: FUUFF) is a uranium exploration company operating in Saskatchewan's Western Athabasca Basin. The company holds 42,961 hectares through its Patterson Lake North Project, comprising three properties: Patterson Lake North (hosting the JR Zone), Minto, and Broach (hosting the Tetra Zone). The properties are located near existing uranium deposits and are accessible via Provincial Highway 955.

Tetra Zone Mineralised Plunge Length Extension from 60m to 135m

The fall 2025 drilling programme consisted of five diamond drill holes totalling 2,628 metres, designed to test plunge continuity within the Tetra Zone shear structure. The programme extended the interpreted mineralised plunge length from 60 metres to 135 metres. A plunge refers to the direction and angle at which a geological feature extends underground, which helps geologists understand where mineralisation may continue.

On the down-plunge western side, holes PLN25-220A and PLN25-220AW1 intersected the shear structure above the expected mineralised interval. PLN25-220A encountered radioactivity and broader shearing, indicating the structure continues at depth. These results suggest further drilling with adjusted angles may be required to intersect the mineralised zone in this area.

On the up-plunge eastern side, hole PLN25-221 confirmed continuity by stepping out 28 metres from hole PLN25-205, which was drilled in July 2025. Approximately 300 metres of shear zone remains untested in the up-plunge direction towards the Athabasca Unconformity. The Athabasca Unconformity is a geological boundary where uranium deposits in the region are commonly found, making it a target of interest for exploration.

Fall 2025 Drill Programme Results and Radioactivity Highlights

Hole PLN25-217 encountered mineralisation over 29.5 metres total length, including 27.5 metres of continuous mineralisation. Within this interval, 2.30 metres registered readings exceeding 10,000 counts per second between 396.70 metres and 407.30 metres depth. Readings above 10,000 counts per second are classified as highly radioactive by the company's measurement standards.

Hole PLN25-221 intersected multiple radioactive intervals: 2.0 metres between 333.5 metres and 335.5 metres depth, 8.5 metres between 338.0 metres and 346.5 metres with peak readings of 4,500 counts per second, and 0.5 metres between 351.0 metres and 351.5 metres. The company uses handheld spectrometers to measure natural gamma radiation in drill core, with readings above 300 counts per second classified as anomalous.

Vice President Exploration Sam Hartmann stated,

"The fall 2025 program was designed to test the plunge continuity of uranium mineralization in the Tetra Zone shear. Drilling extended the known mineralized plunge length from 60m to 135m."

The company notes that spectrometer measurements do not directly correlate with uranium grades and should be considered preliminary indicators pending laboratory assay results.

Future Drilling Priorities Along Strike and Down-Plunge

F3 has identified drilling priorities based on the fall programme results. The company plans to commence follow-up drilling later this month, targeting the approximately 300 metres of untested shear zone extending up-plunge towards the Athabasca Unconformity. The company has designated this area as a first-order priority target.

Down-plunge extensions have also been identified for testing. Holes PLN25-220A and PLN25-220AW1 intersected the structure above the mineralised interval, suggesting mineralisation may continue at depth. Adjusted drill angles will be used to target this area in future programmes.

Sam Hartmann commented,

"The roughly 300m of shear zone remaining in the up-plunge direction toward the Athabasca Unconformity, along with the down-plunge extent, represent first order priority areas for follow-up drilling."

The Tetra Zone is located 13 kilometres south of the JR Zone on the Broach Property.

Milestones and Next Steps

The fall 2025 programme extended the Tetra Zone's interpreted mineralised plunge length from 60 metres to 135 metres. Assay results from the programme are currently being processed at SRC Geoanalytical Laboratories and will be released as they become available. These results will provide uranium grade data for the radioactive intersections identified.

Follow-up drilling is scheduled to commence later this month, targeting the 300 metres of untested shear zone towards the Athabasca Unconformity and down-plunge extensions. The programme aims to further test the continuity and extent of mineralisation at the Tetra Zone.

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