Osisko Intersects 105 Metres Averaging 1.41 g/t Au at Canadian Kirkland

March 27, 2014 (Source: Marketwired) — Osisko Mining Corporation (“Osisko” or the “Corporation”) (TSX:OSK) (FRANKFURT:EWX) is pleased to announce additional new drilling results from Canadian Kirkland, a newly-discovered zone of disseminated gold mineralization located on its 100% owned Kirkland Lake project (see February 21, 2014 press release). The Canadian Kirkland zone is located 750 metres south of Highway 66, approximately 6.5 km southeast of the village of King Kirkland. The table below summarized the results from an additional 12 holes drilled in the mineralized zone:

Hole No. From (m) To (m) Length (m) Au g/t
MU14-29 65.0 86.0 21.0 1.31
And 225.4 262.0 36.6 0.46
And 277.0 291.0 14.0 0.77
And 345.0 372.0 27.0 0.50
MU14-30 56.0 119.0 63.0 0.67
And 223.8 241.0 17.2 0.68
MU14-31 148.0 167.0 19.0 0.71
MU14-32 45.0 56.0 11.0 4.77
including 48.0 49.0 1.00 24.7
MU14-33 204.0 309.0 105.0 1.41
MU14-34 46.0 54.0 8.0 3.21
And 87.0 108.0 21.0 1.17
And 195.0 274.0 79.0 0.82
MU14-35 53.0 115.0 62.0 1.03
And 279.0 295.0 16.0 0.54
MU14-36 NIL
MU14-37 46.2 74.5 28.3 0.61
And 134.0 145.0 11.0 0.50
Hole No. From (m) To (m) Length (m) Au g/t
MU14-38 42.0 55.9 13.9 0.45
81.0 108.0 27.0 0.67
MU14-39 54.0 146.0 92.0 0.68
And 281.0 327.0 46.0 0.45
And 364.0 372.0 8.0 1.16
MU14-40 58.0 154.1 96.1 0.71

Holes MU-14-29 through MU14-40, excepting MU14-36, all intersected mineralization within altered volcanics and were located as far as 470 m east and 100 m west of discovery hole MU14-25. Three additional holes were located along a fence located 575 metres west of the discovery hole (MU14-41 and -42) and 260 m NNE of the discovery hole (MU14-43) and did not intersect significant mineralization.

Mineralization comprises fine disseminated gold and pyrite in a pinkish-gray to brick red altered lithology that has now been identified as strong potassic alteration that completely replaces and partially brecciates the Temiskaming volcanic package. Potassic alteration is a hallmark of porphyry-related gold deposits, including Canadian Malartic, although no porphyry dykes or intrusions have yet been identified in the immediate area of the mineralized zone. Historical work and outcrop indicate that the alteration zone, with or without gold mineralization, extends as far as 1600 metres NW of the discovery hole and includes the historical Commodore Kirkland and 180 mineralized zones. The system is still open to the NE and is truncated to the south by the Cadillac-Larder Lake fault. True thickness and orientation of the Canadian Kirkland zone will be established as geological interpretation of drill sections is completed.

All NQ core assays reported above were obtained by standard 50 g fire assaying-AA finish or gravimetric finish at ALS Chemex laboratories in Val d’Or, Quebec, an ISO/IEC guideline 17025-accredited facility. Reported drill core weighted averages were calculated using a minimum of 0.35 g/t Au over successive sample intervals with maximum internal dilution length of 15 metres. All assays were capped at 10 g/t Au. Lost core intervals, constituting less than 0.5% of reported intervals within mineralized intersections, were all less than one metre long and incorporated as the average grade of adjacent intervals above and below in all length-weighted calculations.

Osisko follows strict QA-QC protocol measures in keeping with industry standards and regulatory reporting requirements. Mr. Robert Wares, D.Sc., P. Geo., Senior Vice President Exploration and Resource Development for Osisko, is the Qualified Person who has reviewed this news release and is responsible for the technical information reported herein, including verification of the data disclosed.

Reject the Inadequate Goldcorp Offer

As previously disclosed, the Osisko Board of Directors has unanimously recommended that Osisko shareholders reject the hostile take-over bid initiated by Goldcorp Inc. and not tender their Osisko shares to the Goldcorp offer. The Osisko Board determined that the Goldcorp offer fails to adequately compensate Osisko shareholders for, among others things, the strategic value of Osisko’s world-class asset base, the significant upside potential of Osisko’s Canadian Malartic Mine, or the increased risk inherent in Goldcorp common shares. The full basis for the Osisko Board’s recommendation is available in a Directors’ Circular, a copy of which is available online at www.osisko.com.

Shareholders who have questions or who may have already tendered their shares to the Goldcorp Offer and wish to withdraw them, may do so by contacting our Information Agent, Laurel Hill Advisory Group at:

North American Toll Free: 1-877-452-7184

Banks, Brokers or collect calls: 416-304-2011

Email: assistance@laurelhill.com

About Osisko Mining Corporation

Osisko Mining Corporation operates the Canadian Malartic Gold Mine in Malartic, Québec and is pursuing exploration on a number of properties, notably in Ontario and Mexico.

Forward-Looking Statements

Certain statements contained in this press release may be deemed “forward-looking statements”. All statements in this release, other than statements of historical fact, that address events or developments that the Corporation expects to occur, are forward looking statements. Forward looking statements are statements that are not historical facts and are generally, but not always, identified by the words “expects”, “plans”, “anticipates”, “believes”, “intends”, “estimates”, “projects”, “potential”, “scheduled” and similar expressions, or that events or conditions “will”, “would”, “may”, “could” or “should” occur including, without limitation, the continuation and success of exploration activities or the development of projects and the Corporation’s view on the quality and the potential of its Canadian Malartic asset and on Goldcorp common shares. Although the Corporation believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, such statements are not guarantees of future performance and actual results may differ materially from those in forward looking statements. Factors that could cause the actual results to differ materially from those in forward-looking statements include gold prices, results of exploration and development activities, the Corporation’s limited experience with production and development stage mining operations, uninsured risks, regulatory changes or sanctions, defects in titles, availability of personnel, materials and equipment, timeliness of government approvals, actual performance of facilities, equipment and processes relative to specifications and expectations, unanticipated environmental impacts on operations market prices, continued availability of capital and financing and general economic, market or business conditions. These factors are discussed in greater detail in the Corporation’s most recent Annual Information Form filed on SEDAR, which also provides additional general assumptions in connection with these statements. The Corporation cautions that the foregoing list of important factors is not exhaustive. Investors and others who base themselves on the Corporation’s forward-looking statements should carefully consider the above factors as well as the uncertainties they represent and the risk they entail. The Corporation believes that the expectations reflected in those forward-looking statements are reasonable, but no assurance can be given that these expectations will prove to be correct and such forward-looking statements included in this press release should not be unduly relied upon. These statements speak only as of the date of this press release.