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Excelsior Mining Announces Collaboration with Nuton, a Rio Tinto Venture

Partnerships & JV

NEWS RELEASE

Excelsior Mining Announces Collaboration with Nuton, a Rio Tinto Venture

January 16, 2023

Excelsior Mining Corp. (TSX: MIN) (FSE: 3XS) (OTCQB: EXMGF) ("Excelsior" or the “Company”)

is pleased to announce that it has entered into a Collaboration Agreement with Nuton LLC, a Rio Tinto

venture, to evaluate the use of its Nuton ™ copper heap leaching technologies at Excelsior’s Johnson

Camp mine in Cochise County, Arizona.

Rio Tinto has developed the Nuton technologies, an extensive portfolio of advanced copper heap

leaching technologies targeted at primary sulfide minerals (including lower grade minerals), which could

not otherwise be processed using traditional leaching or sulfide processing technologies. These

technologies offer the potential to produce additional copper in a cost-effective manner that has significant

environmental benefits and reduces waste from new and ongoing operations.

The first stage of the collaboration involves Nuton completing certain test work on materials collected

from the Company’s Johnson Camp mine project to confirm that suitable conditions exist to deploy the

Nuton technologies. Assuming this test work is successful, the parties would then work toward negotiating

commercial terms for a full-scale deployment of the Nuton technologies at the Johnson Camp mine. Test

work is expected to commence during the first quarter of 2023 with a view toward potentially negotiating

commercial terms dependent on the test results and other factors during the third quarter of 2023.

ABOUT NUTON

Nuton is an innovative new venture that aims to help grow Rio Tinto’s copper business. At the core of

Nuton is a portfolio of proprietary copper leach related technologies and capability – a product of almost

30 years of research and development. The Nuton technologies offer the potential to economically unlock

known low-grade copper sulfide resources, copper bearing waste and tailings, and achieve higher copper

recoveries on oxide and transitional material, allowing for a significantly increased copper production

outcome. One of the key differentiators of Nuton is the potential to deliver leading environmental

performance, including more efficient water usage, lower carbon emissions, and the ability to reclaim

mine sites by reprocessing mine waste.

ABOUT EXCELSIOR MINING

Excelsior “The Copper Solution Company ” is a mineral exploration and production company that owns

and operates the Gunnison Copper Project in Cochise County, Arizona. The project is a low cost,

environmentally friendly in-situ recovery copper extraction project that is permitted to 125 million pounds

per year of copper cathode production. Excelsior also owns the past producing Johnson Camp Mine and

a portfolio of exploration projects, including the Peabody Sill and the Strong and Harris deposits.

For more information on Excelsior, please visit our website at www.excelsiormining.com.

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For further information regarding this press release, please contact:

Excelsior Mining Corp.

Concord Place, Suite 300, 2999 North 44th Street, Phoenix, AZ, 85018.

Shawn Westcott

T: 604.365.6681

E: [email protected]

www.excelsiormining.com

Cautionary Note Regarding Forward-Looking Information

This news release contains "forward-looking information" concerning anticipated developments and events that may

occur in the future. Forward looking information contained in this news release includes, but is not limited to,

statements with respect to: (i) the intention to deploy the Nuton® technology at the Johnson Camp mine and future

production therefrom; and (ii) details of future operational plans.

In certain cases, forward-looking information can be identified by the use of words such as "plans", "expects" or

"does not expect", "budget", "scheduled", "estimates", "forecasts", "intends", "anticipates" or "does not anticipate",

or "believes", or variations of such words and phrases or state that certain actions, events or results "may", "could",

"would", "might", "occur" or "be achieved" suggesting future outcomes, or other expectations, beliefs, plans,

objectives, assumptions, intentions or statements about future events or performance. Forward-looking information

contained in this news release is based on certain factors and assumptions regarding, among other things, the

availability of financing to implement the Company’s operational plans, the estimation of mineral resources and

mineral reserves, the realization of resource and reserve estimates, expectations and anticipated impact of the

COVID-19 outbreak, copper and other metal prices, the timing and amount of future development expenditures, the

estimation of initial and sustaining capital requirements, the estimation of labour and operating costs (including the

price of acid), the availability of labour, material and acid supply, receipt of and compliance with necessary

regulatory approvals and permits, the estimation of insurance coverage, and assumptions with respect to currency

fluctuations, environmental risks, title disputes or claims, and other similar matters. While the Company considers

these assumptions to be reasonable based on information currently available to it, they may prove to be incorrect.

Forward looking information involves known and unknown risks, uncertainties and other factors which may cause

the actual results, performance or achievements of the Company to be materially different from any future results,

performance or achievements expressed or implied by the forward-looking information. Such factors include risks

inherent in the construction and operation of mineral deposits, including risks relating to changes in project

parameters as plans continue to be redefined including the possibility that mining operations may not be sustained

at the Gunnison Copper Project, risks relating to variations in mineral resources and reserves, grade or recovery

rates, risks relating to the ability to access infrastructure, risks relating to changes in copper and other commodity

prices and the worldwide demand for and supply of copper and related products, risks related to increased

competition in the market for copper and related products, risks related to current global financial conditions, risks

related to current global financial conditions and the impact of COVID-19 on the Company’s business, uncertainties

inherent in the estimation of mineral resources, access and supply risks, risks related to the ability to access acid

supply on commercially reasonable terms, reliance on key personnel, operational risks inherent in the conduct of

mining activities, including the risk of accidents, labour disputes, increases in capital and operating costs and the

risk of delays or increased costs that might be encountered during the construction or mining process, regulatory

risks including the risk that permits may not be obtained in a timely fashion or at all, financing, capitalization and

liquidity risks, risks related to disputes concerning property titles and interests, environmental risks and the

additional risks identified in the “Risk Factors” section of the Company’s reports and filings with applicable Canadian

securities regulators.

Although the Company has attempted to identify important factors that could cause actual actions, events or results

to differ materially from those described in forward-looking information, there may be other factors that cause

actions, events or results not to be as anticipated, estimated or intended. Accordingly, readers should not place

undue reliance on forward-looking information. The forward-looking information is made as of the date of this news

release. Except as required by applicable securities laws, the Company does not undertake any obligation to

publicly update or revise any forward-looking information.