Vancouver, British Columbia--(Newsfile Corp. - February 14, 2025) - Sienna Resources Inc. (TSXV: SIE) (OTC Pink: SNNAF) (FSE: A1XCQ0) ("Sienna" or the "Company") is pleased to announce that Sienna has received the drill permit on its 100% owned 'Case Lake West Cesium and Spodumene Pegmatite Project' in Ontario. The Case Lake area of Ontario is one of the most highly prospective regions for cesium in North America. Management cautions that past results or discoveries on properties in proximity to Sienna may not necessarily be indicative of the presence of mineralization on the company's properties.

Jason Gigliotti, President of Sienna Resources stated, "We are very pleased to receive our drill permit. We want to thank the Ontario Government as well as our First Nations partners on this exciting first step towards a much larger goal of finding a new cesium discovery. We anticipate being able to commence drilling shortly. When you consider that this project directly borders Power Metals Corp, whose shares have increased an amazing 85% in just the past 12 trading days based on their Case Lake deposit news, we couldn't be more excited about getting this drill permit in hand and getting boots on the ground as soon as the driller can be mobilized. This is at a time when the junior markets are showing significant strength as we are moving into a phase of significant growth. These next few weeks/months will be a watershed mark for Sienna as we commence our first drill program in a long time."

The 'Case Lake Cesium Project', owned by Power Metals Corp., is a highly prospective lithium, cesium, and tantalum (LCT) project in northeastern Ontario, Canada. Here are some of the highlights:

• High-grade mineralization: Recent drilling programs have consistently confirmed high-grade cesium mineralization, with standout results including up to 20.67% Cesium Oxide (Cs2O). Exceptional Tantalum grades of up to 5328ppm have also been recorded.

• Shallow mineralization: The cesium mineralization is often found at shallow depths, which could make the project more economically viable.

• Multi-element potential: In addition to cesium, the project also contains significant lithium and tantalum mineralization, further enhancing its value.

• World-class asset: The Case Lake project is considered a world-class asset due to the high grades and significant size of the deposit.

• Strategic importance: The project's high-grade cesium and tantalum resources are strategically important for meeting the growing global demand for these critical minerals in advanced technologies.

Overall, the Case Lake Cesium project is a promising project with the potential to become a significant supplier of cesium, lithium, and tantalum.

About Sienna Resources Inc.

Sienna has significantly increased acreage of the "Stonesthrow Gold Project", consisting now of approximately 31,718 contiguous acres prospective for gold. Sienna has also recently acquired the "Case Lake West Cesium and Spodumene Pegmatite Project" in Larder Lake Mining division of Ontario, Canada roughly 100 km north of Kirkland Lake, NE Ontario. This project consists of approximately 7,850 contiguous acres prospective for Cesium and Spodumene Pegmatites. Sienna has also just acquired the 10,357 acre "Uranium Town Project" bordering Denison Mines Corporation, the now 23,134 contiguous acre "Dragon Uranium Project" bordering Cameco Corporation and the 55,440 acre "Atomic Uranium Project" in the world renowned Athabasca Basin of Saskatchewan. Also, Sienna has the "Elko Lithium Project" in Elko County, Nevada consisting of approximately 1830 contiguous acres directly bordering Surge Battery Metals' "Nevada North Lithium Project" in Elko County, Nevada who announced the highest-grade lithium deposit in the USA. Sienna is also one of the larger landholders in Clayton Valley Nevada. Sienna's Clayton Valley projects include the Blue Clay Lithium Project, the Silver Peak South Project, and the Clayton Valley Deep Basin Lithium Project. Clayton Valley is home to the only lithium production in North America, being Albemarle Corp's Silver Peak deposit. This project is also near Tesla Motors Inc.'s Gigafactory in Nevada. On March 18, 2021, Schlumberger New Energy Venture announced the development of a lithium extraction pilot plant with a strategic partnership with Pure Energy. Management cautions that past results or discoveries on properties in proximity to Sienna may not necessarily be indicative of the presence of mineralization on the company's properties.

We seek Safe Harbor.

Qualified Person:

Mr. Frank Bain, PGeo, a qualified person as defined by National Instrument 43-101 has reviewed and approved the scientific and technical disclosure contained within this news release.

"Jason Gigliotti"
President, Director
Sienna Resources Inc.

Statements in this news release that are not historical facts are forward-looking statements. Forward-looking statements are statements that are not historical, and consist primarily of projections - statements regarding future plans, expectations and developments. Words such as "expects", "intends", "plans", "may", "could", "potential", "should", "anticipates", "likely", "believes" and words of similar import tend to identify forward-looking statements. Forward-looking statements in this news release include uncertainty of exploration and development plans regarding the property; commodity price fluctuations; political or economic instability and regulatory changes; currency fluctuations, the state of the capital markets; uncertainty in the measurement of mineral reserves and resource estimates; the Company's ability to attract and retain qualified personnel and management; potential labour unrest; reclamation and closure requirements for mineral properties and the availability of capital to fund the Company's projects, as well as other risks and uncertainties identified under the heading "Risk Factors" in the Company's continuous disclosure documents filed on SEDAR. You are cautioned that the foregoing list is not exhaustive of all factors and assumptions which may have been used. The Company cannot assure you that actual events, performance or results will be consistent with these forward-looking statements, and management's assumptions may prove to be incorrect. These forward-looking statements reflect current expectations regarding future events and operating performance and speak only as of the date hereof and the Company does not assume any obligation to update forward-looking statements if circumstances or management's beliefs, expectations or opinions should change other than as required by applicable law. For the reasons set forth above, you should not place undue reliance on forward-looking statements.

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