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Excelsior Mining Announces Receipt of Permit Amendment for Well Stimulation at the Gunnison Copper Mine

Permits & Approvals

NEWS RELEASE

Excelsior Mining Announces Receipt of Permit Amendment for Well Stimulation at the

Gunnison Copper Mine

April 24th, 2023

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

is pleased to announce that the United States Environmental Protection Agency has issued an

amendment to the Class III Underground Injection Control (“UIC”) Area Permit, that will allow for well

stimulation to occur at the Gunnison Copper Project, located in Cochise County, southeastern Arizona.

Well stimulation has the potential to fundamentally change the performance of the wellfield, and eliminate

or reduce the need for the raffinate neutralization plant. Excelsior intends to proceed to field trials in early

H2 of 2023. Excelsior will submit the well stimulation work plans required by the permit and schedule the

necessary contractors in the near term.

Well stimulation is primarily intended to inflate (open-up) the pre-existing mineralized facture network in

the wellfield to help gas bubbles escape. It can enlarge pre-existing channels and flow paths, increase

pore space and make it possible for solution to move more readily from injection to recovery well. Doing

so should improve connectivity between these wells, improve flow rates, sweep efficiency and copper

production. Previously Excelsior commissioned a leading engineering and environmental consulting firm

to undertake well stimulation modelling on a selection of wells within the current wellfield. The model

showed that well stimulation successfully inflated pre-existing fractures over significant volumes around

the central well within the 5-spot pattern.

The amended permit will be effective on May 26th, 2023.

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.

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

2

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 potential of well stimulation to improve performance of the Company’s mineral

projects; (ii) the details of future well stimulation trials, including the expected timeline, and (iii) future production

and production capacity from the Company’s mineral projects.

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

amended permit will not be appealed, work plans will be approved in a timely manner, 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 an appeal of the permit amendment that delays its effectiveness,

risks related to the delay in approval of work plans, 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.