Excelsior Mining Secures US$75 Million Project Financing Package

Phoenix, October 31, 2018 - Excelsior Mining Corp. (TSX: MIN) (FSE: 3XS) (OTCQX: EXMGF) ("Excelsior" or the "Company") is pleased to announce that the Company has entered into an agreement for a US$75 million project financing package. This comprehensive funding plan will enable Excelsior to transition the fully-permitted Gunnison Copper Project in southeastern Arizona into America's next new copper producer.

Stephen Twyerould, the President & CEO, commented, "In today's challenging mining market, only quality projects are able to secure funding. This financing delivers superior long-term economics for shareholders and allows us to quickly move into construction this year. Excelsior's pathway to achieving producer status is now clear, and we look forward to bringing the USA's next new strategic metal producer online in 2019."

Shaun Usmar, CEO of Triple Flag Mining Finance Ltd., commented, "Triple Flag is excited to partner with Excelsior to finance the Gunnison Copper Project. Our flexible and innovative financing will allow the Gunnison Copper Project to quickly proceed to construction and production over the next year, delivering a new, low-cost source of American copper. We congratulate the Excelsior team for its impressive progress in advancing this project to fully funded status."

Financing Package Highlights

The US$75 million project financing package (collectively, the "Financing") will be provided by Triple Flag Mining Finance Bermuda Ltd. ("Triple Flag"), and consists of a US$65 million copper metal stream (the "Stream") and a concurrent US$10 million private placement of common shares of Excelsior (the "Equity Placement"). The closing of these funding commitments is subject to various conditions, including the approval of the Toronto Stock Exchange. The Financing is expected to close during November 2018 (the "Closing Date").

Benefits for Excelsior

• The Financing provides Excelsior with a comprehensive project funding solution that would cover all capital expenditures and working capital requirements related to the start-up of the Gunnison Copper Project.
• The Stream is not subject to interest payments and is unsecured, thereby allowing for future project debt financing to expand the project production capacity up to the targeted 125 million pounds per year.
• The Stream provides an option for Triple Flag to provide an additional US$65 million in funding for the second stage expansion of the Gunnison Copper Project, while also preserving the right of Excelsior to buy-down 50% of the Stream.
• The Equity Placement provides further alignment between Excelsior and Triple Flag, with Triple Flag acting as a true project partner.
• This transaction allows Excelsior to complete the construction without incurring project debt financing or the issuance of a large number of shares in a poor equity market.

Details of the Financing

Upfront Deposit

Excelsior and its subsidiaries, Excelsior Mining Arizona, Inc. ("Excelsior Arizona") and Excelsior Mining JCM, Inc. ("JCM"), have entered into a metals purchase and sale agreement (the "Stream Agreement") with Triple Flag, whereby Triple Flag has committed to fund a deposit of US$65 million (the "Stage 1 Upfront Deposit") against the future sale and delivery by Excelsior Arizona of a percentage of the refined copper production from the Gunnison Copper Project. Excelsior will sell to Triple Flag this percentage of refined copper at a price equal to 25% of the copper spot price. The exact percentages of copper production to be sold to Triple Flag varies as per the total production capacity. These percentages are detailed in the table below.

"At full production of 125 million pounds per annum, and using the same US$2.75 copper price from our Feasibility Study, the Stream would add just an additional 7 cents per pound to our industry-leading all-in-sustaining operating costs of US$1.23 per pound," added Stephen Twyerould. "With this Stream, the Gunnison Copper Project would still be one of the lowest cost pure copper producers in the United States, and one of the lowest capex per pound copper projects in the industry."

In consideration of the Stream, Excelsior shall also issue to Triple Flag 3.5 million five-year common share purchase warrants, whose five-year term shall begin on the Closing Date, entitling Triple Flag to purchase 3.5 million Excelsior common shares at a strike price of C$1.50 per share issued.

Triple Flag Expansion Option and Excelsior Buy-Down Right

Subsequent to notice from Excelsior that the Company will be expanding production capacity to an amount equal to or greater than 50 million pounds per annum, Triple Flag will have the option to increase its stream participation by paying an additional US$65 million (the "Expansion Upfront Deposit").

Excelsior also retains the option to reduce the amount of the Stream by 50% by making a buy-down payment to Triple Flag (the "Buy-Down Payment"). The amount of the Buy-Down Payment depends on whether Triple Flag has exercised its option to provide the Expansion Upfront Deposit. The Buy-Down Payment is calculated as an amount that provides Triple Flag with an internal rate of return of 15% on 50% of the Stage 1 Upfront Deposit and, if applicable, 15% on 50% of the Expansion Upfront Deposit (in each case after taking into account the value of Stream deliveries (net of the 25% purchase price payment for such deliveries) made to Triple Flag prior to its payment).

The table below shows the percentage of production to be acquired by Triple Flag based on scenarios that include Triple Flag's Expansion Option and Excelsior's Buy-Down Right.

Equity Placement

In conjunction with the Stream, Excelsior will complete the Equity Placement to raise proceeds of US$10 million (net of applicable fees and expenses). The Equity Placement will consist of the issuance to Triple Flag of an aggregate of 13,818,977 Excelsior common shares at an aggregate subscription price of US $10 million, or equal to approximately Cdn$0.95 per share at current exchange rates. In addition, affiliates of Greenstone Resources L.P. retain a pre-emptive right over the issuance of common shares of the Company. The overall size of the Equity Placement may be increased up to US$20 million dependent upon Greenstone's decision to exercise its pre-emptive right and in what proportion.

Advisors

Blake, Cassels & Graydon LLP acted as legal counsel to the Company. Torys LLP acted as legal counsel to Triple Flag. Clarksons Platou Securities AS and BMO Capital Markets acted as financial advisors to the Company.

About Triple Flag

Triple Flag Mining Finance Bermuda Ltd. and Triple Flag Mining Finance Ltd. together constitute Triple Flag Mining. Triple Flag Mining primarily targets streaming and royalty investments in the mining sector with backing by Elliott Management Corporation, an experienced global investment firm with more than $35 billion of assets under management. Triple Flag Mining's focus is on being a leading sought-after long-term funding partner to mining companies throughout the commodity cycle. In less than 2 years, Triple Flag has committed over US$800 million to the mining sector, with a primary focus on precious metal streaming and royalty investments. For more information, visit http://www.tripleflagmining.com.

About Excelsior Mining

Excelsior "The Copper Solution Company" is a mineral exploration and development company that is advancing the Gunnison Copper Project in Cochise County, Arizona. The project is a fully-permitted, advanced staged, low cost, environmentally friendly in-situ recovery copper extraction project. The Feasibility Study projected an after-tax NPV of US$ 807 million and an IRR of 40% using a US$ 2.75 per pound copper price and a 7.5% discount rate.

Excelsior's technical work on the Gunnison Copper Project is supervised by Stephen Twyerould, Fellow of AUSIMM, President & CEO of Excelsior and a Qualified Person as defined by National Instrument 43-101. Mr. Twyerould has reviewed and approved the technical information contained in this news release.

Additional information about the Gunnison Copper Project can be found in the technical report filed on SEDAR at www.sedar.com entitled: "Gunnison Copper Project, NI 43-101 Technical Report, Feasibility Study" dated effective December 17, 2016.

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

ON BEHALF OF THE EXCELSIOR BOARD

"Stephen Twyerould"
President & CEO

For further information regarding this press release, please contact:

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

JJ Jennex, Vice President, Corporate Affairs
T: 604 723 1433
E: info@excelsiormining.com
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 closing the Financing, (ii) whether, and the extent which, Triple Flag will increase its stream and provide Excelsior additional funding (iii) Greenstone's participation in the Equity Placement, (iv) the results of the Feasibility Study, including operating and capital cost estimates and the economic benefits from the Gunnison Copper Project; (v) the timeline for commencement of construction and commercial production from the Gunnison Copper Project; and (vi) the ability to mine the Gunnison Copper Project using in-situ recovery mining techniques.

In certain cases, forward-looking information can be identified by the use of words such as "plans", "expects" or "does not expect", "is expected", "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" or "will be taken", "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, 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, the availability of necessary financing and materials to continue to develop and construct the Gunnison Copper Project in the short and long-term, the progress of development activities, the receipt of necessary regulatory approvals, 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 exploration and development 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 commence at the Gunnison Copper Project, risks relating to variations in mineral resources and reserves, grade or recovery rates resulting from current exploration and development activities, 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 and in the mining industry generally, risks related to current global financial conditions, uncertainties inherent in the estimation of mineral resources, access and supply risks, 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 development process, regulatory risks, financing, capitalization and liquidity risks, including the risk that the financing necessary to fund the exploration and development activities at the Gunnison Copper Project may not be available on satisfactory terms, or at all, risks related to disputes concerning property titles and interest, 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.