Osisko Intersects 479 g/t Au Over 2.0 Metres At Lynx

(Toronto, November 28, 2017)  Osisko Mining Inc. (OSK:TSX. “Osisko” or the “Corporation”) is pleased to provide new results from the ongoing drill program at its 100% owned Windfall Lake gold project located in the Abitibi greenstone belt, Urban Township, Eeyou Istchee James Bay, Québec.  The 800,000 metre drill program combines definition, expansion and exploration drilling in and around the main Windfall gold deposit and the adjacent Lynx deposit (located immediately NE of Windfall).  Significant new analytical results from 27 intercepts in 18 drill holes focused on infill and expansion drilling in the Lynx deposit are presented below.

Highlights from the new results include: 479 g/t Au over 2.0 metres in OSK-W-17-1169, and 27.4 g/t Au over 2.2 metres in OSK-W-17-1128.  Maps showing hole locations and full analytical results are available at www.osiskomining.com.

Notes:

1. True widths are estimated at 65 – 80% of the reported core length interval.  See “Quality Control” below.
2. Definitions: HW = Hanging Wall, QTV = Quartz-Tourmaline Vein, VNCR = Crustiform Vein

OSK-W-17-1030 intersected 9.25 g/t Au over 2.3 metres in Lynx 1. Mineralization consists of trace pyrite with local 5% pyrite in association with pervasive silica flooding hosted in a sericitized rhyolite.

OSK-W-17-1047 intersected 3.95 g/t Au over 2.6 metres related to Lynx 1 Corridor. Mineralization is composed of 7% disseminated to locally semi-massive pyrite and 2% stringers in a pseudo-crustiform vein hosted in gabbro.

OSK-W-17-1064 intersected Lynx HW returning 4.42 g/t Au over 3.0 metres. Mineralization is composed of trace disseminated pyrite in a chloritized, fuchsitized and slightly sericitized gabbro.

OSK-W-17-1072-W1 returned four intervals in Lynx Corridor: 4.50 g/t Au over 2.0 metres related to Lynx HW, 3.79 g/t Au over 2.0 metres, 9.52 g/t Au over 2.0 metres and 6.09 g/t Au over 3.0 metres all related to Lynx 4. The first interval is composed 10% pyrite with 5% ptygmatic tourmaline veinlets hosted in a silicified and sericitized gabbro. Mineralization from the Lynx 4 intervals is composed up to 5% pyrite in patches and stringers hosted in sericitized rhyolite with pervasive silica flooding.

OSK-W-17-1096 intersected 3.48 g/t Au over 2.3 metres. Mineralization is composed of 30% quartz veins with 2% pyrite hosted in a silicified and chloritized rhyolite.

OSK-W-17-1098 intersected 8.51 g/t Au over 2.6 meters related to Lynx 2. Mineralization includes up to 2% pyrite stringers and trace pyrite fragments in a sericitized and silicified fragmental felsic intrusive.

OSK-W-17-1102 intersected 3.58 g/t Au over 2.0 metres related to Lynx 1. Mineralization is composed of 5% pyrite stringer within a smoky quartz vein hosted in a sericitized and silicified rhyolite.

OSK-W-17-1104 intersected 3.61 g/t Au over 2.0 metres in Lynx 4. Mineralization is composed of 10% disseminated pyrite and 3% pyrite stringers hosted in a sericitized and silicified rhyolite with local breccia with carbonate matrix.

OSK-W-17-1108 intersected 4.55 g/t Au over 2.0 metres. The interval is related to Lynx 1 and consists of 5% pyrite-tourmaline stringers and 5% pyrite with pervasive silica flooding hosted in a fragmental felsic intrusive.

OSK-W-17-1111 intersected two intervals: 11.0 g/t Au over 2.0 metres and 4.18 g/t Au over 2.0 metres. The first interval is related to Lynx 1 and 2 and consists of trace pyrite in a strongly sericitized rhyolite. The second interval is composed of 10% centimetre-scale quartz veins with trace pyrite hosted in a sericitized rhyolite.

OSK-W-17-1112 intersected Lynx 1 returning 4.09 g/t Au over 2.0 metres. Mineralization is composed of 2% cluster and fragment pyrite and trace pyrite stringer in a sericitized fragmental felsic dike.

OSK-W-17-1113 intersected 4.66 g/t Au over 5.4 metres related to Lynx 2 and 3.11 g/t Au over 2.3 metres related to Lynx. The first interval is composed of 5% pyrite clusters and stringers within a pervasive silica flooding zone and trace pyrite-tourmaline vein at the contact between rhyolite and gabbro. The second interval from Lynx 1 corresponds with quartz veining and tourmaline veins creating a breccia texture with trace pyrite and chalcopyrite in a silicified gabbro.

OSK-W-17-1120 intersected Lynx 2 returning 4.93 g/t Au over 2.0 metres and Lynx HW with 3.24 g/t Au over 2.2 metres and 5.68 g/t Au over 2.7 metres. The first interval is composed of pyrite clusters and stringers and a quartz veining hosted in a slightly sericitized and silicified rhyolite. Mineralization in Lynx HW is up to 5% disseminated or clustered pyrite with pervasive silica flooding in a rhyolite.

OSK-W-17-1128 intersected 27.4 g/t Au over 2.2 metres related to Lynx 4 and 9.71 g/t Au over 2.0 metres related to Lynx 6. The mineralization from the first interval is composed of 5% pyrite stringers, 2% pyrite in tourmaline ptygmatic veins and a quartz-carbonate-chlorite vein hosted in a partially bleached andesite. The second interval consist of 1% pyrite stringers in a silicified and sericitized andesite.

OSK-W-17-1132 intersected 8.28 g/t Au over 2.0 metres within Lynx 3 Corridor. Mineralization consists of 3% pyrite both disseminated and as stringers within a low core angle crustiform veins hosted in a strongly fuschitized gabbro.

OSK-W-17-1149 intersected Lynx HW returning 11.0 g/t Au over 2.2 metres. Mineralization is composed of 15% pyrite-tourmaline stringers and quartz-carbonate veins and clusters in a strongly fuchsitized and silicified gabbro.

OSK-W-17-1153 intersected 10.4 g/t Au over 2.1 metres related to Lynx 1. Mineralization is composed of 5% disseminated pyrite and pyrite stringers in a pervasive silica flooding zone with sericite and fuchsite at contact between rhyolite and gabbro.

OSK-W-17-1169 intersected 479 g/t Au over 2.0 metres and 5.13 g/t Au over 2.0 metres related to the Lynx Corridor. The first interval is composed of local visible gold in centimeter scale smoky quartz with ptygmatic tourmaline veinlets and 7% pyrite stringers hosted in a bleached and fuchsitized gabbro at contact with felsic porphyry intrusive. The second interval consists in 2% pyrite within quartz tourmaline veins and disseminated pyrite in a chloritized and slightly sericitized gabbro.

Qualified Person
The scientific and technical content of this news release has been reviewed, prepared and approved by Mr. Louis Grenier, M.Sc.A., P.Geo. (OGQ 800), Project Manager of the Windfall Lake gold project, who is a “Qualified Person” as defined by National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI 43-101”).

Cautionary Note Regarding Forward-Looking Information
This news release contains “forward-looking information” within the meaning of the applicable Canadian securities legislation that is based on expectations, estimates, projections and interpretations as at the date of this news release. The information in this news release about the Windfall Lake gold deposit being one of the highest grade resource-stage gold projects in Canada; the current 800,000 metre drill program; the significance of new results from the ongoing drill program at the Windfall Lake gold project; the significance of assay results presented in this press release; the type of drilling included in the drill program (definition drilling, expansion drilling to the NE of the main deposit and adjacent Lynx deposit, and exploration drilling on the greater deposit and Urban-Barry project area); potential mineralization; the potential to extend mineralization up and down-plunge and at depth at the Windfall Lake gold deposit; the ability to realize upon any mineralization in a manner that is economic; the ability to complete any proposed exploration activities and the results of such activities, including the continuity or extension of any mineralization; and any other information herein that is not a historical fact may be “forward-looking information”. Any statement that involves discussions with respect to predictions, expectations, interpretations, beliefs, plans, projections, objectives, assumptions, future events or performance (often but not always using phrases such as “expects”, or “does not expect”, “is expected”, “interpreted”, “managements view”, “anticipates” or “does not anticipate”, “plans”, “budget”, “scheduled”, “forecasts”, “estimates”, “believes” or “intends” or variations of such words and phrases or stating that certain actions, events or results “may” or “could”, “would”, “might” or “will” be taken to occur or be achieved) are not statements of historical fact and may be forward-looking information and are intended to identify forward-looking information. This forward-looking information is based on reasonable assumptions and estimates of management of the Corporation. at the time it was made, involves known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of Osisko to be materially different from any future results, performance or achievements expressed or implied by such forward-looking information. Such factors include, among others, risks relating to the ability of exploration activities (including drill results) to accurately predict mineralization; errors in managements geological modelling; the ability of Osisko to complete further exploration activities, including drilling; property interests in the Windfall Lake gold project; the ability of the Corporation to obtain required approvals and complete transactions on terms announced; the results of exploration activities; risks relating to mining activities; the global economic climate; metal prices; dilution; environmental risks; and community and non-governmental actions. Although the forward-looking information contained in this news release is based upon what management believes, or believed at the time, to be reasonable assumptions. Osisko cannot assure shareholders and prospective purchasers of securities of the Corporation that actual results will be consistent with such forward-looking information, as there may be other factors that cause results not to be as anticipated, estimated or intended, and neither Osisko nor any other person assumes responsibility for the accuracy and completeness of any such forward-looking information, Osisko does not undertake, and assumes no obligation, to update or revise any such forward-looking statements or forward-looking information contained herein to reflect new events or circumstances, except as may be required by law.

For further information please contact:
John Burzynski. President and Chief Executive Officer
Telephone: (416) 363-8653