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Excelsior Mining Files PEA Technical Report for Strong & Harris Copper-Zinc-Silver Deposit in Southern Arizona

Technical Reports (NI 43-101) Economic Studies

NEWS RELEASE

Excelsior Mining Files PEA Technical Report for Strong & Harris Copper-Zinc-Silver

Deposit in Southern Arizona

October 25th, 2021

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

is pleased to announce that it has filed a National Instrument (“ NI”) 43-101 Technical Report entitled

“Estimated Mineral Resources and Preliminary Economic Analysis, Strong and Harris Copper-Zinc-Silver

Project, Cochise County, Arizona” dated effective of September 9, 2021 (the “ Report”) on SEDAR at

www.sedar.com. The Report is with respect to Excelsior’s Preliminary Economic Assessment (“PEA”) on

the Strong and Harris copper-zinc-silver deposit in southern Arizona; the results of which were announced

in a September 9, 2021 news release.

Roland Goodgame, SVP Business Development for the Company commented “Excelsior’s focus clearly

remains the ramp up of the Gunnison ISR Project. To support this the Company is moving ahead with its

strategy to restart and operate the Johnson Camp mine to produce cashflow while Gunnison ramps up

and the raffinate neutralization plant is designed and constructed. With its attractive economics and

upside potential, the Strong and Harris deposit is a complementary asset that has the potential to allow

Excelsior to become a larger and longer-term producer than previously envisioned.”

Highlights of the Strong & Harris PEA (US Dollars):

Mining of the Strong and Harris deposit would be by traditional open pit with high-grade underground

mining of the remaining sulfides at the bottom of the pit. The PEA has been completed by Mine

Development Associates, a division of RESPEC (MDA), the highlights of which are tabulated below

assuming a $3.50/lb. copper price, $1.28/lb. zinc price, and $110/ton acid cost.

Mine Life ~7 years

Material Mined ~54 M ton

Cu/Zn Grades 0.56% / 0.68%

Cu/Zn Produced 437 M lb / 575 M lb

Initial Capital $328 million

Operating Costs ($/lb CuEq) $1.76

Average Cu/Zn annual production 62 Mlbpa / 82 Mlbpa

Pre-Tax NPV/IRR (8% discount rate) $325M / 25%

The table below sets out the sensitivities of the NPV and IRR to copper price:

Cu Price US$/lb NPV Pre-Tax

@ 8%

IRR NPV After-Tax

@ 8%

IRR

$ 3.00 $ 111,387 14% $ 38,999 10%

$ 3.25 $ 218,426 19% $ 113,438 15%

$ 3.50 $ 325,466 25% $ 186,958 19%

$ 3.75 $ 432,505 30% $ 260,306 23%

$ 4.00 $ 539,544 35% $ 333,264 27%

The PEA is preliminary in nature and includes inferred mineral resources that are considered too

speculative geologically to have the economic considerations applied to them that would enable them to

be categorized as mineral reserves. There is no certainty that the conclusions reached in the PEA will be

realized. Mineral resources that are not mineral reserves do not have demonstrated economic viability.

The Company’s next steps with Strong and Harris are a drill program targeting adjacent geophysical

anomalies with the goal of expanding the mineral resource, metallurgical test work and completion of a

feasibility study.

Additional information about the Strong & Harris Project can be found in the technical report filed on

SEDAR at www.sedar.com entitled: “Estimated Mineral Resources and Preliminary Economic Analysis,

Strong and Harris Copper-Zinc-Silver Project, Cochise County, Arizona” dated effective of September 9,

2021.

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.

The technical information contained in this news release with respect to Strong & Harris has been

reviewed and approved by the following Independent Qualified Persons from MDA, a division of

RESPEC:

• Mr. Jeff Bickel, C.P.G., of MDA, Reno, Nevada (geology and mineral resource)

• Mr. Michael Gustin, PhD., P.Geo, of MDA, Reno, Nevada (geology and mineral resource)

• Robert Bowell, PhD, C.Chem, C.Geol, SRK Consulting (UK) Limited, Cardiff, Wales, UK (mineral

processing and metallurgical testing, recovery methods)

• Mr. Thomas L. Dyer, P.E., of MDA, Reno, Nevada (mining methods, capital and operating costs, and

economic analysis).

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

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 future development plans for the Gunnison Project and its status as a low cost

environmentally friendly in-situ recovery copper extraction project;(ii) the intention to mine Johnson Camp and future

production therefrom; (iii) the results of the Preliminary Economic Assessment on Strong & Harris; and (iv) future

development of exploration 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

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.