Excelsior Closes Johnson Camp Mine Acquisition and US$12.0 Million Financing

VANCOUVER, BRITISH COLUMBIA--(Marketwired - Dec. 15, 2015) -

NOT FOR DISTRIBUTION TO UNITED STATES NEWSWIRE SERVICES OR FOR DISSEMINATION IN THE UNITED STATES

Excelsior Mining Corp. (TSX VENTURE:MIN)(FRANKFURT:3XS)(OTCQX:EXMGF) ("Excelsior" or the "Company") is pleased to announce that it, through a wholly-owned Arizona subsidiary, has closed the acquisition of all of the assets of Nord Resources Corporation, as they relate to the Johnson Camp Copper Mine (the "Johnson Camp Transaction"). The Johnson Camp Copper Mine ("JCM") is located immediately adjacent to Excelsior's Gunnison Copper Project in southeastern Arizona (the "Gunnison Project"). The Company also announces that it has closed concurrent financings of US$12.0 million. For details of the Johnson Camp Transaction, please see Excelsior's news release dated October 8, 2015 - Excelsior to Purchase Johnson Camp Mine and Raise US$12 Million.

Commenting on the closing of the Johnson Camp Transaction, Stephen Twyerould, President and CEO of the Company, said, "The acquisition of the production facilities at Johnson Camp Mine puts Excelsior in an excellent position and represents the delivery of yet another impressive milestone. We remain absolutely confident in our ability to successfully process copper solutions through the existing SX-EW plant, which is expected to significantly reduce both our initial capital requirements and the time required for the start-up of the Gunnison Copper Project. Based on this acquisition, Excelsior intends to provide an updated prefeasibility study in Q1 of 2016, and the feasibility study is scheduled to be completely before the end of 2016."

Concurrent Financing

Excelsior has also closed concurrent financings with an affiliate of Greenstone Resources L.P. ("Greenstone"), for total gross proceeds of US$12.0 million. The financings consists of a private placement of common shares (the "Private Placement") for gross proceeds of US$4 million over two tranches and the sale of 2% gross revenue royalty on the Gunnison Copper Project (the "Royalty Financing") for gross proceeds of US$8 million.

Stephen Twyerould added, "Our ability to complete a significant and largely non-dilutive financing in one of the most challenging environments for junior mining companies is a testament to the quality of the Gunnison Copper Project and our management team. Following upon an exhaustive review of the data from our feasibility work programs, the Greenstone financing represents a major endorsement and allows for the project to maintain its pace and momentum as we head into 2016."

With respect to the Private Placement, on November 30, 2015 the Company closed the first tranche of the Private Placement ("Tranche 1") through the issuance of 8,655,510 common shares to Greenstone for total gross proceeds of US$1.5 million. Please see Excelsior's news release dated December 1, 2015 - Excelsior Announces Closing of First Tranche of Greenstone Financing.

The Company has now closed the second tranche of the Private Placement ("Tranche 2") pursuant to which Greenstone has purchased, by way of a treasury offering, common shares of Excelsior at a price of Cdn$0.23 per common share for total gross proceeds of US$2.5 million. Settlement occurred in United States dollars and the exact number of common shares issued has been determined based on a Cdn$/US$ exchange rate of Cdn$1.00 being equal to US$0.7533 (the "Exchange Rate"). The Exchange Rate was determined using the average of the noon Cdn$/US$ exchange rate, as reported by the Bank of Canada, for the 10 days prior to the execution of the term sheet. Greenstone has acquired 14,425,852 common shares, which represent approximately 10.42% of Excelsior's issued and outstanding common shares.

As result of the closing of Tranche 1 and Tranche 2 of the Private Placement, Greenstone now holds a total of 55,550,869 common shares, which represents approximately 40.14% of Excelsior's issued and outstanding common shares. The common shares issued to Greenstone pursuant to Tranche 2 are subject to a statutory four month hold period expiring on April 15, 2016. In addition Greenstone has agreed that it will not, for a period of one year, dispose of the common shares it acquired pursuant to the Private Placement.

The net proceeds of the Private Placement and Royalty Financing will be used for the consideration payable in the Johnson Camp Transaction, the continued development of the company's Gunnison Copper Project and for working capital and general corporate purposes.

The securities being offered hereby have not been, nor will they be, registered under the United States Securities Act of 1933, as amended, and may not be offered or sold in the United States or to, or for the account or benefit of, U.S. persons absent registration or an applicable exemption from the registration requirements. This press release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of the securities in any state or province in which such offer, solicitation or sale would be unlawful.

About Greenstone

Greenstone is a private equity fund specialising in the mining and metals sector. The Greenstone team has over 80 years of experience in the sector covering all aspects of mining project development. Further details on Greenstone can be found at www.greenstoneresources.com.

Greenstone is acquiring the securities in the offering described herein for investment purposes. Depending on market conditions and other factors, Greenstone may from time to time acquire and/or dispose of securities of Excelsior or continue to hold its current position.

A copy of the early warning report required to be filed with the applicable securities commission in connection with the transaction will be available on SEDAR at www.sedar.com and can be obtained by contacting Jo-Anna Duquemin Nicolle and Sadie Morrisson at +44 1481810100. Greenstone's address is set out below.

Greenstone Contact Information:

Greenstone Resources L.P.

1st Floor, Royal Chambers

St Julian's Avenue

St Peter Port, Guernsey

GY1 3JX

Channel Islands

About Excelsior

Excelsior is a mineral exploration and development company that is advancing the Gunnison Copper Project. The Excelsior management team consists of experienced professionals with proven track records of advancing mining projects into production. Further 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, Prefeasibility Study" dated February 14, 2014.

Dr. Stephen Twyerould, Fellow of AUSIMM, President and CEO of Excelsior, and a Qualified Person as defined by NI 43-101, has reviewed and approved the technical information disclosed in this news release.

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

ON BEHALF OF THE EXCELSIOR BOARD

Mark J. Morabito, Executive Chairman

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 use of the SX-EW plant at Johnson Camp, (ii) the potential reduction in the initial capital costs and the timeline to first production at the Gunnison Project, (iii) the timeline to complete a prefeasibility study and feasibility study, (iv) the anticipated use of proceeds of the financings; and (v) the advancement of the Gunnison Project.

Such forward-looking information can be identified by the use of the word "will". 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 exploration and development expenditures, the ongoing care and maintenance costs associated with Johnson Camp, 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 explore and develop the Gunnison Project in the short and long-term, the progress of exploration and development activities, the receipt of necessary regulatory approvals, the completion of the permitting process, 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 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, including risks relating to the acquisition of the necessary licenses and permits, financing, capitalization and liquidity risks, including the risk that the financing necessary to fund the exploration and development activities at the Gunnison 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.

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 release, and no securities regulatory authority has either approved or disapproved of the contents of this release.