Osisko Intersects 61.6 Metres Averaging 1.44 g/t Au at Bidgood

MONTREAL, QUEBEC--(Marketwired - Dec. 4, 2013) - Osisko Mining Corporation ("Osisko") (TSX:OSK)(FRANKFURT:EWX) is pleased to announce that 2013 drilling on the 100%-owned Kirkland Lake property has revealed the presence of disseminated porphyry-style mineralization (similar to that of Canadian Malartic) in drill hole BG13-361. This hole intersected 61.6 metres grading 1.44 g/t Au (3.46 g/t uncut), and was collared approximately 300 metres northwest of the Bidgood deposit currently being evaluated by Osisko. Details of the intersection are as follows:

The intersection cut what is interpreted as part of the Bidgood porphyry cluster, which outcrops northwest to southwest of the Bidgood deposit. The 2013 summer surface litho-geochemical sampling program revealed that the Bidgood porphyry cluster is anomalous in gold (threshold value of 0.015 ppm, attaining locally 2.07 ppm) over an area approximately 1300 x 1000 metres, suggesting the presence of a large "fertile" porphyry system. Mineralization in BG13-361 occurs predominantly as finely disseminated pyrite-gold in fractured and partially hematized red to buff porphyry, as well as in surrounding altered Temiskaming-type tuffs and conglomerates. Short high-grade intersections, such as 160.3 g/t Au from 38.0-38.8 metres, are associated with quartz veins and vein breccias. The syenite-hosted mineralization is distinct from that in the historical Bidgood deposit, which consists of pyrite-quartz-chlorite veins and stockworks.

The Bidgood porphyry cluster is a high-priority target that will be the object of a 1000 to 2000 metre reconnaissance drilling program in Q1 2014.

All NQ core assays reported above were obtained by standard fire assay with gravimetric finish at Polymet laboratories located in Cobalt, Ontario. Reported drill core weighted averages were calculated using a minimum of 0.40 g/t Au over successive intervals with maximum 10 metres internal dilution. Lost core and samples that returned assays below detection limit within mineralized intersections were assigned a 0.001 g/t grade in all length-weighted calculations. Osisko follows strict QA-QC protocol measures in keeping with industry standards and regulatory reporting requirements. Mr. Dan McCormack, PGeo. and Kirkland Lake Project General Manager 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.

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