McEwen Mining Continues to Expand Los Azules' Large, High-Grade, Mineral Resource

Tue Feb 5, 2013 4:30pm EST

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McEwen Mining Inc.

February 5, 2013 - 04:30:00 PM

McEwen Mining Continues to Expand Los Azules' Large, High-Grade, Mineral

TORONTO, ONTARIO--(Marketwire - Feb. 5, 2013) - McEwen Mining Inc.
(NYSE:MUX)(TSX:MUX) is pleased to announce an updated, Canadian National
Instrument 43-101 compliant ("NI 43-101") mineral resource estimate for its
100% owned Los Azules Copper Project in San Juan Province, Argentina. Most
importantly, drilling has expanded contained copper in the inferred resource
category by 29% to 13.95 billion lbs. Contained copper in the indicated
resource decreased slightly to 4.45 billion lbs. The expanded resource
incorporates 6,966 meters of new drilling from 10 additional holes. The
resource remains open laterally, to depth and along strike (to view
cross-sections displaying the resource click here). Los Azules is one of the
world's largest, undeveloped, high-grade, open pit copper projects which,
contains significant growth potential. 

Table 1. Los Azules Copper Project - Comparison of Previous and Current
Mineral Resource Estimates

                                        January 2013 Resource               
          June 2012 Resource Estimate      Estimate Update        % Change  
  Cut-off  Tonnage    Cu              Tonnage    Cu                         
   Grade   (million Grade    Cu lbs   (million Grade    Cu lbs    Contained 
   (Cu%)   tonnes)   (%)   (billions) tonnes)   (%)   (billions)   Cu lbs   
Indicated Resource                                                          
   0.35      323     0.65     4.64      310     0.65     4.45        -4%    
Inferred Resource                                                           
   0.35      948     0.52    10.82     1,302    0.49    13.95       +29%    
(i)Details for gold and silver resources are included in Table 2.           

"Los Azules is a unique asset, in terms of size and grade, for McEwen Mining.
This year's exploration drilling has demonstrated that there is significant
potential to expand the resource well beyond our previous understanding of the
deposit," stated Rob McEwen, Chief Owner.

Drilling this season represents the first time a meaningful amount of deeper
drilling has occurred at Los Azules. Prior to this year the deepest drill hole
was 650 meters. This season there has been a total of 6 holes that exceeded
700 meters. This deeper drilling has begun to identify a potential parallel
trend, west of the original Los Azules ore-body. Copper mineralization
discovered within this trend occurs near surface and also at depth (down to
1,050 meters below surface). This is significant because it may indicate that
previous shallow drilling, which makes up the majority of the Los Azules
resource, failed to adequately test the deeper potential of the deposit. As a
result, many new exploration targets have emerged.

McEwen Mining has begun work on an updated Preliminary Economic Assessment
(PEA) which is expected to be completed in the third quarter of this year. The
updated PEA will be based on a significantly larger mineral resource and will
evaluate the possibility of increasing the daily throughput. The PEA will also
incorporate further metallurgical studies currently being done on the
possibility of producing copper cathode instead of a concentrate and
processing low grade mineralized material not previously considered, via a
heap leach. The advantage of producing a copper cathode is that it would
eliminate the contemplated slurry pipeline through Chile and would reduce
Argentina's export tax on concentrate.

This news release has been submitted by Andrew Elinesky, Vice President -
Argentina, for the Company.

About Los Azules

Los Azules is a large undeveloped copper porphyry system located in western
San Juan Province within a belt of porphyry copper deposits that straddles the
Chilean/Argentine border. This belt contains some of the world's largest
copper deposits, including Codelco's El Teniente and Andina mines, Anglo
American's Los Bronces mine, Antofagasta PLC's Los Pelambres mine and
Xstrata's El Pachon project, among others. Los Azules is one of the world's
largest, highest grade, undeveloped copper-porphyry deposits not owned by a
major base metal company.

Table 2. Los Azules Mineral Resource Estimate

In order to exhibit reasonable prospects for economic viability, the mineral
resource estimate has been contained within a conceptual open pit shell
generated using general technical and economic parameters that are defined at
the end of this news release. The base case cut-off grade of 0.35% Cu is
highlighted in the table. 

                                           Au                Ag             
                                         Grade             Grade            
              Tonnage    Cu              (grams            (grams           
Cut-off Grade (million Grade    Cu lbs    per     Au Oz     per     Ag Oz   
    (Cu%)     tonnes)   (%)   (billions) tonne) (millions) tonne) (millions)
Indicated Resource                                                          
     0.15       414     0.55     5.04     0.06     0.83     1.8      23.6   
     0.20       397     0.57     4.97     0.06     0.80     1.8      22.6   
     0.25       369     0.59     4.84     0.06     0.76     1.8      21.1   
     0.30       338     0.62     4.65     0.07     0.72     1.8      19.6   
     0.35       310     0.65     4.45     0.07     0.68     1.8      18.3   
     0.40       283     0.68     4.22     0.07     0.63     1.9      16.9   
     0.45       254     0.71     3.95     0.07     0.57     1.9      15.4   
     0.50       225     0.74     3.64     0.07     0.52     1.9      13.8   
     0.55       195     0.77     3.30     0.07     0.46     1.9      12.1   
     0.60       165     0.80     2.92     0.07     0.40     1.9      10.2   
     0.65       134     0.85     2.49     0.08     0.33     1.9      8.2    
     0.70       105     0.89     2.07     0.08     0.26     1.9      6.5    
Inferred Resource                                                           
     0.15      3,378    0.34    25.33     0.04     4.84     1.7     181.4   
     0.20      2,890    0.37    23.44     0.05     4.35     1.7     159.8   
     0.25      2,318    0.40    20.61     0.05     3.71     1.8     134.9   
     0.30      1,774    0.44    17.32     0.05     3.01     1.9     108.9   
     0.35      1,302    0.49    13.95     0.06     2.34     2.0      83.3   
     0.40       914     0.53    10.76     0.06     1.72     2.1      60.8   
     0.45       622     0.59     8.03     0.06     1.21     2.1      42.8   
     0.50       422     0.64     5.96     0.06     0.85     2.2      29.7   
     0.55       290     0.69     4.43     0.06     0.60     2.2      20.6   
     0.60       201     0.75     3.31     0.07     0.42     2.3      14.5   
     0.65       143     0.80     2.51     0.07     0.31     2.3      10.5   
     0.70       103     0.84     1.91     0.07     0.22     2.3      7.6    
(i)   "Tonnes" is stated in metric and is equivalent to 2205 lbs.           
(ii)  Estimated contained metal values may be subject to rounding errors.   

Details on the parameters of the resource estimate are as follows:

--  The resource estimation was based on data from 173 drill holes
    comprising a total length of 50,612 meters of drilling completed to the
    end of December 2012. 

--  There were a total of 23,178 individual samples selected for analysis.
    The samples were collected and analyzed in accordance with industry
    standards. Splits from the drill core samples were submitted to either
    Alex Stewart in Mendoza or ALS Chemex or ACME in Santiago, Chile for
    fire assay and ICP analysis. Accuracy of results is tested through the
    systematic inclusion of standards, blanks and check assays. 

--  The January 2013 mineral resource estimate for the Los Azules Copper
    Project was prepared under the direction of Robert Sim, P.Geo. of SIM
    Geological Inc. The mineral resource estimate uses drill hole sample
    assay results and the interpretation of a geologic model that relates to
    the spatial distribution of copper in the deposit. Interpolation
    characteristics were defined based on the geology, drill hole spacing
    and geostatistical analysis of the data. Block grade estimates were done
    using Ordinary Kriging (OK) with a nominal block size measuring 20
    meters long, 20 meters wide and 15 meters high. Resources are classified
    according to their proximity to sample data locations and are reported,
    as required under NI 43-101, according to the CIM Definition Standards
    for Mineral Resources and Mineral Reserves. 

--  Mineral resources, which are not mineral reserves, do not have
    demonstrated economic viability. 

--  The quantity and grade of reported Inferred resources are uncertain in
    nature and there has been insufficient exploration to classify these
    inferred resources as Indicated or Measured, and it is uncertain if
    further exploration will result in upgrading them to an Indicated or
    Measured category. 

--  As required under NI 43-101, reasonable prospects for economic viability
    of the mineral resources has been exhibited by the application of a
    resource limiting pit shell built about copper grades in the model using
    a projected metal price of US$2.75 per lb. Cu, mining costs of US$1.00
    per tonne, milling and G&A costs of US$4.25 per tonne, 100% recoveries
    and an average pit slope of 34 degrees. 

About McEwen Mining ( 

The goal of McEwen Mining is to qualify for inclusion in the S&P 500 by 2015
by creating a high growth, low-cost, mid-tier gold producer focused in the
Americas. McEwen Mining's principal assets consist of the San Jose Mine in
Santa Cruz, Argentina (49% interest); the El Gallo Complex in Sinaloa, Mexico;
the Gold Bar Project in Nevada, US; the Los Azules Project in San Juan,
Argentina and a large portfolio of exploration properties in Argentina, Nevada
and Mexico. 

McEwen Mining has 296,024,859 shares issued and outstanding. Rob McEwen,
Chairman, President and Chief Owner, owns approximately 25% of the shares of
the Company. As of December 31, 2012, McEwen Mining had cash and liquid assets
of approximately US$70 million and is debt free.

Technical Information:

Robert Sim, P.Geo., who is a Qualified Person and independent of McEwen
Mining, each as defined by National Instrument 43-101 ("NI 43-101") has
reviewed and approved the technical content of this news release related to
the mineral resource estimate presented herein. Notwithstanding, Bruce Davis,
PhD, FAusIMM, who is a Qualified Person and independent of McEwen Mining, as
defined by NI 43-101 and responsible for the quality control for the assaying
of the Los Azules drill core has reviewed the assay quality control
information. All samples were collected in accordance with industry standards.
Splits from the drill core samples were submitted to the ACME sample
preparation laboratory in Mendoza, Argentina, and then transferred to ACME's
laboratory in Santiago, Chile for fire assay and ICP analysis. Accuracy of
results is tested through the systematic inclusion of standards, blanks and
check assays. The mineral resource estimate referenced in this press release
was prepared in January 2013 by Robert Sim, P.Geo. and Bruce Davis, PhD,

For additional information about the Los Azules project see the Technical
Report titled "Los Azules Porphyry Copper Project, San Juan Province,
Argentina" dated August 1, 2012, with an effective date of June 15, 2012,
prepared by D. Ernest Winkler, P.Eng., Robert Sim, P.Geo., Bruce Davis, PhD,
FAusIMM and James K. Duff, P.Geo., all of whom are qualified persons and all
of whom are independent of McEwen Mining, each as defined by NI 43-101. The
foregoing report is available under the Corporation's profile on SEDAR

Cautionary Note to U.S. Investors:

McEwen Mining reports its resource estimates in accordance with standards of
the Canadian Institute of Mining, Metallurgy and Petroleum referred to in
Canadian National Instrument 43-101 ("NI 43-101"). These standards are
different from the standards generally permitted in reports filed with the
SEC. Under NI 43-101, McEwen Mining reports measured, indicated and inferred
resources, measurements which are generally not permitted in filings made with
the SEC. According to Canadian NI 43-101 criteria, the estimation of measured
resources and indicated resources involve greater uncertainty as to their
economic feasibility than the estimation of proven and probable reserves.
Under SEC Industry Guide 7 criteria, measured, indicated and inferred
resources are considered Mineralized Material. The SEC considers that in
addition to greater uncertainty as to the economic feasibility of Mineralized
Material compared to proven and probable reserves, there is also greater
uncertainty as to the existence of Mineralized Material. U.S. investors are
cautioned not to assume that measured or indicated resources will be converted
into economically mineable reserves. The estimation of inferred resources
involves far greater uncertainty as to their existence and economic viability
than the estimation of other categories of resources.

Caution Concerning Forward-Looking Statements

This press release contains certain forward-looking statements and
information, including "forward-looking statements" within the meaning of the
Private Securities Litigation Reform Act of 1995. The forward-looking
statements and information expressed, as at the date of this press release,
McEwen Mining Inc.'s (the "Company") estimates, forecasts, projections,
expectations or beliefs as to future events and results. Forward-looking
statements and information are necessarily based upon a number of estimates
and assumptions that, while considered reasonable by management, are
inherently subject to significant business, economic and competitive
uncertainties, risks and contingencies, and there can be no assurance that
such statements and information will prove to be accurate. Therefore, actual
results and future events could differ materially from those anticipated in
such statements and information. Risks and uncertainties that could cause
results or future events to differ materially from current expectations
expressed or implied by the forward-looking statements and information
include, but are not limited to, risks related to the cost of transferring or
otherwise allocating funds between operating jurisdictions, factors associated
with fluctuations in the market price of precious metals, mining industry
risks, political, economic, social and security risks associated with foreign
operations, risks associated with the construction of mining operations and
commencement of production and the projected costs thereof, risks related to
litigation, property title, the state of the capital markets, environmental
risks and hazards, uncertainty as to calculation of mineral resources and
reserves and other risks. Readers should not place undue reliance on
forward-looking statements or information included herein, which speak only as
of the date hereof. The Company undertakes no obligation to reissue or update
forward-looking statements or information as a result of new information or
events after the date hereof except as may be required by law. See McEwen
Mining's Annual Report on Form 10-K for the fiscal year ended December 31,
2011 and other filings with the Securities and Exchange Commission, under the
caption "Risk Factors", for additional information on risks, uncertainties and
other factors relating to the forward-looking statements and information
regarding the Company. All forward-looking statements and information made in
this news release are qualified by this cautionary statement.

To view Figure 1, please visit the following link:

To view the cross-sections displaying the resource, please visit the following

McEwen Mining Inc.
Jenya Meshcheryakova
Investor Relations`
(647) 258-0395 ext 410 or Toll Free: (866) 441-0690
(647) 258-0408 (FAX)

McEwen Mining Inc.
Mailing Address
181 Bay Street Suite 4750
Toronto, ON M5J 2T3
PO box 792



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adequacy or accuracy of the contents of this news release, which has been
prepared by management of McEwen Mining Inc.