Excelsior Mining Corp. (TSX VENTURE:MIN)(OTCQX:EXMGF)(FRANKFURT:3XS)
("Excelsior" or the "Company") is pleased to announce results from recent
metallurgical tests on copper oxide mineralization from its North Star deposit,
part of Excelsior's Gunnison Copper project, located in southeastern Arizona.


Two types of tests were performed.



1.  Submerged leach tests. These modified column-leach tests generated
    recoveries of acid soluble copper in the range of 82% to 95% over
    periods from 49 to 99 days. Higher recoveries were achieved with higher
    acid concentrations or longer leach times. 
2.  Acid consumption tests. These tests were designed to evaluate relative
    acid consumption from in-situ leaching versus standard metallurgical
    testing. The tests demonstrated that standard metallurgical testing
    (including the submerged leach tests) significantly over- estimates acid
    consumption compared to values expected under in-situ operating
    conditions. 



"We are extremely pleased with the high recovery and low acid consumption from
these recent metallurgical tests," stated Stephen Twyerould, President and CEO
of Excelsior. "We are looking forward to the positive impact of combining these
results with the recent favourable hydrological results as Excelsior continues
to complete the work required to prepare a pre-feasibility study."


Acid consumption test details

Due to the nature of the copper oxide mineralization at North Star, combined
with standard metallurgical testing procedures on drill core, more of the
un-mineralized rock known as "gangue" is inadvertently exposed to the acid
solution than would be expected during normal in-situ mining conditions. This
overexposure results in inflated acid consumption rates from metallurgical
testing compared to those expected during actual in-situ operational conditions.


To demonstrate this, two pairs of identical samples were collected from the
Martin formation within the North Star deposit. Man-made exposures on one half
of each pair were coated with an impermeable acid resistant epoxy, leaving the
naturally occurring, mineralized fractures, uncoated. In this way, the leach
solution could only react with the naturally occurring fractures in the coated
sample, just as it would during real-world in-situ leaching conditions. As a
control, the other half of the pair was left uncoated, as would occur in
standard metallurgical testing (including the submerged leach tests described
below). See photo showing epoxy and non-epoxy coated samples prior to testing
at:
http://www.excelsiormining.com/images/Projects/GunnisonProject/minnr20130214%20fig%201%20photo.jpg.
All samples were then submerged in a dilute acid solution and the amount of
copper leached and acid consumed were monitored.


After 72 days submerged in dilute sulfuric acid, the acid consumption was up to
82% less for the epoxy coated samples (simulating in-situ conditions), compared
to the uncoated samples (see Table 1 below). While the testing is continuing,
these results clearly show the inadvertent overestimation of acid consumption
that occurs during standard metallurgical testing as compared to expected
operational conditions.




Table 1. Results of comparative acid consumption tests.                     
                                                                            
----------------------------------------------------------------------------
                                      Acid Consumption(i)   % change in acid
Sample             Epoxy                        lbs/lb Cu        consumption
----------------------------------------------------------------------------
C1                 Uncoated                         11.30                   
----------------------------------------------------------------------------
C2                 Coated                            2.07               -82%
----------------------------------------------------------------------------
F4                 Uncoated                         23.93                   
----------------------------------------------------------------------------
F3                 Coated                           13.99               -42%
----------------------------------------------------------------------------
(i) Acid consumption in pounds of acid consumed per pound of copper         
recovered                                                                   



The acid consumption tests are being conducted by independent consultant
Mountain States R&D International, Inc. of Tucson, Arizona under the supervision
of Dr. Ronald J. Roman of Leach, Inc., Tucson, Arizona. Dr. Roman has reviewed
and approved the technical information disclosed above in this news release and
is an independent consultant who is a Qualified Person (QP) as defined by
National Instrument (NI) 43-101. Dr. Roman has verified the data underlying the
test results by designing the test procedure, supervising the test work,
obtaining all the analytical data over the life of the experiment and performing
the calculations presented above.


Submerged leach tests details

Submerged leach testing employs a protocol similar to column leach testing but
modified to more closely reflect conditions during in-situ leaching. These tests
were designed to be repeatable, and to evaluate the response of mineralization
to in-situ leaching at different flow rates and acid concentrations.


To date, five of the 13 tests have been completed and the results are presented
in Table 2 below. The remaining eight tests are still under active leaching and
are expected to conclude in the next 30 to 60 days. The five tests completed are
from the Lower Abrigo rock formation.


Higher acid concentrations (e.g. column 9) and/or longer leach times (e.g.
column 13) generated higher recoveries, indicating 100% acid soluble copper is
recoverable given sufficient time, acid concentration and economics.




Table 2. Results from submerged leach tests on the Lower Abrigo formation.  
                                                                            
----------------------------------------------------------------------------
       Head Grade(1)                                Recovery,               
           % Cu                                             %               
      --------------                                ---------               
                         Flow        Acid                               Acid
          Cu Cu acid rate(2), content(3),       Days  Cu acid Consumption(5)
Column total soluble   lph/m2    gpl acid leached(4)  soluble        lbs/lbs
----------------------------------------------------------------------------
9       0.31    0.23       22          15         61       95             19
----------------------------------------------------------------------------
10      0.33    0.26       37          10         49       85           12.6
----------------------------------------------------------------------------
11      0.28    0.21       22          10         61       87           17.3
----------------------------------------------------------------------------
12      0.29    0.21       22           5         61       82            9.7
----------------------------------------------------------------------------
13      0.28    0.20       11           5         99       92           12.6
----------------------------------------------------------------------------

1.  Calculated head grade 
2.  Flow rate in litres per hour per cross-sectional square metre 
3.  Acid concentration in grams per litre of free acid 
4.  Days leached includes one or two days of post leach rinsing but does not
    include the extended post leach rinsing period 
5.  Acid consumption in pounds of acid consumed per pound of copper
    recovered 



The submerged leach tests are being conducted by independent laboratory SGS
Metcon of Tucson, Arizona under the supervision of Dr. Ronald J. Roman, an
independent consultant who is a Qualified Person as defined by NI 43-101. Dr.
Roman has reviewed and approved the technical information disclosed in this news
release. Dr. Roman has verified the data underlying the test results by
designing the test procedure, supervising the test work, obtaining all the
analytical data over the life of the experiment and performing the calculations
presented above.


More detailed information concerning these metallurgical tests can be found on
the Excelsior website at: http://excelsiormining.com/index.php/projects.


Project Summary

The Gunnison Copper Project is located in a remote section of Cochise County in
southeastern Arizona. The focus of the project is the North Star deposit, which
currently has a total Indicated mineral resource of 3.21 billion pounds of oxide
copper (511 M tons at 0.31%) and an Inferred mineral resource of 0.88 billion
pounds of oxide copper (159 M tons at 0.28%). This oxide mineral resource has
the potential to be mined using in-situ recovery methods. Mineral resources
which are not mineral reserves do not have demonstrated economic viability.


About Excelsior

Excelsior is an exploration company with a copper project located within the
Copper Porphyry Belt of Arizona. The Gunnison Copper Project is located close to
the required infrastructure and its oxide copper resource has the potential to
be mined using in-situ recovery methods. The Excelsior team consists of
experienced professionals with proven track records of advancing projects
towards production.


Excelsior's exploration work on the Gunnison Property is supervised by Dr.
Stephen Twyerould, Fellow of AUSIMM, President and CEO of Excelsior, and a
Qualified Person as defined by NI 43-101. Dr. Twyerould has reviewed and
approved the technical information disclosed in the "Project Summary" and "About
Excelsior" sections of this news release.


Further details about Excelsior can be found at: http://www.excelsiormining.com.
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 Preliminary Economic Assessment, NI 43-101 Technical Report" dated
November 18, 2011.


ON BEHALF OF THE EXCELSIOR BOARD 

Stephen Twyerould, President & CEO

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 estimation of inferred and indicated mineral
resources; (ii) the future implications of the metallurgical test results; (iii)
production from the Gunnison Project; (iv) the completion of a pre-feasibility
study; (v) expected acid consumption rates and; (vi) the ability to mine
Gunnison using in-situ recovery mining techniques are forward-looking
statements.


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, the realization of resource
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 environmental assessment 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, 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 Annual Information Form for the most recently completed financial year
or other reports and filings with applicable Canadian securities regulations.


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.


FOR FURTHER INFORMATION PLEASE CONTACT: 
Excelsior Mining Corp.
JJ Jennex
Vice President, Corporate Affairs
604-681-8030 x240
info@excelsiormining.com
www.excelsiormining.com
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