Saturday, September 19, 2026
MiningNewsTerminal
Saturday, September 19, 2026 Admin

SIEN.V ·

Multi-Hole Drill Program Now Underway on "Case Lake West Cesium and Spodumene Pegmatite Project" in Ontario Bordering Power Metals Corp.'s Cesium Deposit

Exploration Programs

Multi-Hole Drill Program Now Underway on

"Case Lake West Cesium and Spodumene

Pegmatite Project" in Ontario Bordering Power

Metals Corp.'s Cesium Deposit

Vancouver, British Columbia--(Newsfile Corp. - March 6, 2025) - Sienna Resources Inc. (TSXV: SIE)

(OTC Pink: SNNAF) (FSE: A1XCQ0) ("Sienna" or the "Company") is pleased to announce that the

multi- hole drill program is now underway on Sienna's 100% owned 'Case Lake West Cesium and

Spodumene Pegmatite Project' in Ontario.

Jason Gigliotti, President of Sienna Resources, stated, "We are extremely pleased and excited to finally

be underway on a drill program.

It has been a long time since Sienna has drilled.

The 'Case Lake West

Cesium and Spodumene Pegmatite Project' has potential for cesium.

When you consider that this

project directly borders Power Metals Corp., whose shares increased approximately 300% in February

based on their Case Lake deposit news, we couldn't be more excited about getting boots on the ground.

These next few weeks/months will be a watershed mark for Sienna as the drilling occurs."

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 (Cs

O).

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.

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.

Sienna Resources Ownership Map

To view an enhanced version of this graphic, please visit:

https://images.newsfilecorp.com/files/854/243516_4702ad7d544ecb39_002full.jpg

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.

If you would like to be added to Sienna's email list, please email

[email protected]

for

information or join our twitter account at

@SiennaResources

.

Contact Information

Tel:

1.604.646.6900

Fax: 1.604.689.1733

www.siennaresources.com

[email protected]

"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.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the

policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this

press release.

To view the source version of this press release, please visit

https://www.newsfilecorp.com/release/243516