VANCOUVER, BRITISH COLUMBIA--(Marketwired - Jul 7, 2015) - Excelsior Mining Corp. (TSX VENTURE:MIN)(3XS.F)(EXMGF) ("Excelsior" or the "Company") is pleased to announce an updated mineral resource estimate at the Gunnison Copper Project in Arizona. The prior North Star mineral resource, reported in January, 2014, has now been updated to include the results of 13 additional diamond drill holes, totalling 17,110 feet that were completed in December, 2014. The drill program was designed to convert a large part of the inferred mineral resource into the measured & indicated mineral resource categories.

The combined measured & indicated mineral resources estimate has increased by 26.6% as a result of the conversion of some of the 1.39 billion pounds of Cu (388 million short tons at 0.21% Cu) in the inferred mineral resource category into the measured & indicated categories.

The total mineral resource estimate for the North Star Deposit is based on results from 122 drill holes totalling 158,785 feet and is effective as of June 1, 2015. Mr. Michael M. Gustin, with the independent firm Mine Development Associates of Reno, Nevada, is a Qualified Person as defined by NI 43-101 and is responsible for this mineral resource estimate. He has verified, reviewed and approved the technical disclosure contained in this news release. Mr. Gustin has verified the data underlying the results by reviewing the drilling, sampling, assay, and quality assurance and quality control data, as well as the geologic interpretations completed by Excelsior. The estimate is classified as a measured, indicated or inferred mineral resource, consistent with the CIM definitions referred to in NI 43-101. Excelsior is not aware of any environmental, permitting, legal, title, taxation, socio-political, marketing or other issues which may materially affect its estimate of mineral resources.

The North Star mineral resources were modeled to respect the detailed lithologic, structural, and oxidation modeling completed by Excelsior. Copper mineral domains were interpreted on 100-foot spaced, east-west vertical cross sections that span the 2.3-mile north-south and 1.3-mile east-west extents of the deposit. These domains were then used to explicitly constrain the estimation of copper grades into 50 x 100 x 25 foot (x, y, z) model blocks using 20-foot composites and inverse-distance interpolation. The grade estimation is further controlled by the incorporation of a number of unique search ellipses that reflect the various orientations of the modeled structural zones, as well as the strike and dip of the favorable stratigraphic units in areas unaffected by the structures.

All samples were prepared from manually split half-core sections on site in Arizona. Split drill core samples were then sent to Skyline Assayers & Laboratories ("Skyline") in Tucson, Arizona, an independent laboratory, for Total Copper and Sequential Copper analyses. Skyline is accredited with international standard ISO/IEC 17025:2005 General Requirements for the Competence of Testing and Calibration Laboratories. Total Copper, Acid Soluble Copper and Cyanide Soluble Copper were analyzed. Excelsior has no relationship with Skyline Labs other than Skyline being a service provider. Standards, blanks, and duplicate assays are included at regular intervals in each sample batch submitted from the field as part of an ongoing Quality Assurance/Quality Control Program.

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.

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 details of the mineral resource estimate; and (ii) 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 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.