Significant new analytical results from 90 intercepts in 52 drill holes focused on infill and expansion drilling in the Lynx deposit are presented below. Osisko continues to extend the known Lynx zones of mineralization through the application of the Windfall geological model and as the density of drilling increases.
OSK-W-17-1015 intersected 4.02 g/t Au over 2.1 metres and 6.26 g/t Au over 2.6 metres in Lynx 2 and 8.38 g/t Au over 2.3 metres in a crustiform vein within the Lynx Corridor. The first interval corresponds to a sericitized and silicified rhyolite containing trace disseminated pyrite and a decimetre scale quartz-tourmaline vein. The second interval is composed of 4% pyrite clusters and trace pyrite stringers in a strongly chloritized gabbro with weak silica and sericite alteration. The third interval corresponds with a decimetre scale quartz-tourmaline vein in a gabbro with sericite, silica and chlorite alteration.
OSK-W-17-1019 intersected 11.3 g/t Au over 2.0 metres, 3.21 g/t Au over 2.2 metres and 9.04 g/t Au over 2.0 metres. The first interval is composed of local visible gold within a pervasive silica flooding zone with 30-40% pyrite and 5% pyrite tourmaline stringers associated with a five-centimetre tourmaline ptygmatic vein. This interval is the the south-west extension of the Lynx 1 Corridor, 250 metres south-west of OSK-W-17-1052 (7.65 g/t Au over 4.1 metres, previously reported, October 30, 2017). The second interval is related to Lynx 4, geometry to be determined, and is composed of 5% pyrite stringers in a sericitized and weakly silicified porphyry felsic dike. The third interval is composed of a partially dismembered quartz vein and local visible gold.
OSK-W-17-1024 intersected Lynx 1 with 3.97 g/t Au over 2.0 metres and 3.64 g/t Au over 2.0 metres. Mineralization is composed of trace disseminated pyrite in a sericitized porphyritic felsic dike.
OSK-W-17-1027 returned 3.85 g/t Au over 2.0 metres, 12.2 g/t Au over 2.2 metres and 3.47 g/t Au over 2.5 metres in the Lynx Corridor. The first interval is in Lynx 2 and composed of trace disseminated pyrite in a sericitized and strongly chloritized gabbro. The second interval corresponds to a 20-centimeter-wide quartz-carbonate vein in the same gabbroic unit. The third interval is related to the Lynx HW and is composed of 20% pyrite stringers and 10% disseminated pyrite in a bleached gabbro.
OSK-W-17-1028 intersected 8.18 g/t Au over 2.0 metres in the Lynx Corridor. Mineralization is composed of up to 3% pyrite clusters and 10% pyrite stringers in a sericitized and silicified porphyric felsic dike. It is in the south west extension of the Lynx 1 Corridor, 145 metres southwest of OSK-W-17-1052 (7.65 g/t Au over 4.1 metres, previously reported, October 30, 2017). Geometry of this intercept is yet to be determined.
OSK-W-17-1040 intersected 5.9 g/t Au over 2.0 metres in Lynx 2. The interval is composed of highly silicified and fuschitized felsic intrusive with 5% pyrite stringers, 2% disseminated pyrite and local visible gold.
OSK-W-17-1043 intersected 3.11 g/t Au over 2.0 metres. Mineralization is composed of trace pyrite fragments and 1% pyrite stringers in a chloritized and slightly silicified fragmental felsic intrusive. This interval is located between Lynx 1 and Lynx 2.
OSK-W-17-1044 intersected 3.60 g/t Au over 2.1 metres in Lynx 2. Mineralization is composed of 4% disseminated and clustered pyrite in a sericitized fragmental felsic rock.
OSK-W-17-1059 intersected 83.0 g/t Au over 2.0 metres and 17.7 g/t Au over 2.4 metres in Lynx 3 and Lynx 1, respectively. Mineralization is composed of 3% pyrite fragments and 1% pyrite stringers in a chloritized and slightly sericitized gabbro.
OSK-W-17-1067 intersected Lynx HW returning 4.54 g/t Au over 3.1 metres. Mineralization is composed of 3% pyrite stringers and 1% disseminated pyrite at a chloritized and sericitized contact between an andesite and a fragmental felsic dike.
OSK-W-17-1072-W2 intersected six intervals all related to Lynx 4: 5.24 g/t Au over 3.1 metres, 17.7 g/t Au over 2.0 metres, 8.60 g/t Au over 3.0 metres, 10.9 g/t Au over 2.0 metres, 17.1 g/t Au over 2.3 metres and 4.16 g/t Au over 2.3 metres. The first interval consists of traces of ptygmatic tourmaline veins and pyrite-tourmaline stringers in a four-metre interval composed of sericitized and partially silicified rhyolite within a large gabbro. The other five intervals consist of chloritized and slightly sericitized rhyolite containing 1% pyrite stringers, trace to 20% tourmaline-pyrite veins and local, but intense, pervasive silica flooding.
OSK-W-17-1072-W3 intersected Lynx 4 returning 4.02 g/t Au over 2.4 metres. Mineralization is composed of trace disseminated pyrite at the sericitized contact between rhyolite and small porphyry felsic dike.
OSK-W-17-1085 intersected 4.41 g/t Au over 2.5 metres and 29.8 g/t Au over 2.2 metres in Lynx 1 and Lynx 2, respectively. The first interval is composed of trace disseminated and stringer pyrite with 2% crustiform veins hosted in a chloritized and slightly silicified gabbro. The second interval consist of 5% disseminated pyrite in a sericitized and strongly chloritized gabbro.
OSK-W-17-1099 intersected 7.87 g/t Au over 2.0 metres in Lynx 1. Mineralization consists of 5% disseminated pyrite and 2% pyrite-tourmaline stringers in a silicified and slightly sericitized rhyolite.
OSK-W-17-1104 intersected 48.7 g/t Au over 2.6 metres in the Lynx Corridor. Mineralization is composed of a quartz-carbonate vein containing multiple local visible gold over 0.4 metres hosted in a fuchsitized and strongly chloritized gabbro.
OSK-W-17-1112 intersected 9.96 g/t Au over 2.1 metres in the Lynx HW. Mineralization is composed of up 3% pyrite stringers and 1% disseminated pyrite at a sericitized contact between a rhyolite and a chloritized-fuchsitized gabbro.
OSK-W-17-1113 intersected 6.35 g/t Au over 2.1 metres and 8.46 g/t Au over 4.6 metres. The first interval is in Lynx 2 and is composed of trace pyrite stringers and clusters in quartz veining within a sericitized and silicified rhyolite. The second interval is composed of 5% pyrite clusters at a contact between a pervasively silica flooded rhyolite and a sericitized and chloritized gabbro with trace ptygmatic tourmaline veining and located between Lynx 1 and Lynx 2.
OSK-W-17-1128 intersected 17.4 g/t Au over 3.0 metres in Lynx 4. Two additional intervals returned 4.49 g/t Au over 2.0 metres and 8.25 g/t Au over 2.0 metres in an area with geometry yet to be determined. The first interval is composed of 2% pyrite stringers in a chloritized and sericitized andesite with 30% smoky quartz veinlets. The second interval is composed of slightly silicified and sericitized porphyry felsic dike with trace pyrite stringers, clusters, and 1% quartz veining. The third interval is composed of 5% pyrite in pervasive silica flooding and disseminated pyrite in a slightly sericitized rhyolite.
OSK-W-17-1131 intersected Lynx 1 with 3.28 g/t Au over 2.0 metres. Mineralization is composed of trace pyrite fragments in a sericitized fragmental felsic intrusion.
OSK-W-17-1166-W1 intersected 3.32 g/t Au over 3.0 metres, 3.13 g/t Au over 5.7 metres, and 3.12 g/t Au over 2.0 metres. The first and second intervals are composed of up to 5% pyrite stringer and 4% fragments in a sericitized and silicified fragmental felsic intrusive with fuchsite. The second interval contains 15% crustiform veins. Geometry of this intercept is yet to be determined; it is 230 metres north east of and in the trend of Lynx 2. The third interval is in Lynx 1 and composed of 8% interstitial and fragmental pyrite in a chloritized rhyolite.
OSK-W-17-1166-W2 intersected 5.06 g/t Au over 2.2 metres related to a shear zone within the Lynx Corridor. Mineralization is composed of 5% pyrite clusters and 1% disseminated pyrite in a rhyolite with moderate silica, sericite and carbonate alteration. The mineralization is in contact with a chloritized andesite.
OSK-W-17-1166-W3 returned four intervals; 4.21 g/t Au over 2.6 metres, 6.63 g/t Au over 2.1 metres, 6.96 g/t Au over 2.1 metres and 4.05 g/t au over 2.0 metres. The first interval in Lynx 1 is composed of dismembered crustiform veins with 3-5% disseminated pyrite hosted in gabbro with sericite, chlorite, carbonates and fuchsite alteration. The second interval is composed of 5% pyrite clusters and stringers with 30% quartz-tourmaline veins in a silicified rhyolite. The third interval, in Lynx 6, is composed of a strongly sericitized mafic dike with 5% pyrite stringers and massive sulfides over 1 metre with quartz tourmaline and quartz carbonates veinlets. The fourth interval consists of 6% pyrite stringers and up 3% sphalerite in a sericitized gabbro at contact with porphyric felsic dike in an area with geometry yet to be determined.
OSK-W-17-1168 intersected 6.05 g/t Au over 4.0 metres in Lynx 2. Mineralization is composed of 1% pyrite stringers hosted in a sericitized and slightly silicified felsic porphyritic dike.
OSK-W-17-1169 intersected Lynx 1 returning 9.75 g/t Au over 3.0 metres. Mineralization is composed of trace disseminated pyrite in a strongly chloritized, moderately fuchsitized and carbonatized gabbro.
OSK-W-17-1170 intersected 4.22 g/t Au over 2.0 metres and 3.23 g/t au over 2.0 metres within the Lynx Corridor. The first interval consists of a quartz crustiform veins with 15% pyrite stringers and fuchsite alteration. The mineralization is hosted in a sericitized felsic porphyritic dike. The second interval is related to a quartz crustiform vein with traces of clustered or disseminated pyrite hosted in a hematized and sericitized felsic porphyritic dike.
OSK-W-17-1177 intersected 16.0 g/t Au over 5.5 metres and 22.9 g/t Au over 2.4 metres in Lynx 1 and Lynx 3, respectively. The first interval is composed of 1% pyrite stringers and 5% pyrite associated with pervasive silica flooding. The interval is hosted in a felsic porphyritic intrusion. The second interval is at the contact between a silicified and sericitized rhyolite and a gabbroic dike. Mineralization is composed of 5% pyrite stringers.
OSK-W-17-1181 intersected 4.46 g/t Au over 2.5 metres in Lynx 4. Mineralization is composed of 3% pyrite in quartz-tourmaline veinlets in a rhyolite with pervasive silica flooding, and local sericite and fuchsite alteration. This interval extends Lynx 4 approximatively 75 metres north-east of OSK-W-17-909 (11.8 g/t Au over 2.0 metres previously reported September 18, 2017, and 301 g/t Au over 6.2 metres and 10.7 g/t Au over 6.0 metres previously reported November 14, 2017).
OSK-W-17-1181-W1 intersected 27.9 g/t Au over 2.4 metres, 14.4 g/t Au over 2.3 metres and 4.66 g/t Au over 2.1 metres. The first interval corresponds to a quartz-tourmaline vein with local visible gold hosted in an altered gabbro containing fuschite and sericite. The vein is located between Lynx 1 and Lynx 4. The second interval is a small silicified porphyritic felsic dike with 15% pyrite and correlates to Lynx 4. The third interval consists of 15% pyrite in silicified contact between a sericite gabbro and an altered rhyolite.
OSK-W-17-1181-W2 intersected 5.92 g/t Au over 6.0 metres in Lynx 1, and 4.60 g/t Au over 4.0 metres, 10.5 g/t Au over 5.0 metres and 41.0 g/t Au over 2.1 metres in Lynx 4. The first interval is composed of 7% pyrite clusters and stringers in a sericitized gabbro. The three intervals related to Lynx 4 are composed of moderately sericitized and silicified rhyolite with 2% pyrite clusters and stringers. The high grade in the third interval consists of a small felsic dike with sericite and silica alteration with 5% pyrite clusters and 1% pyrite stringers.
OSK-W-17-1181-W3 intersected 5.31 g/t Au over 3.5 metres in Lynx 4. Mineralization is composed of 3% pyrite stringers, 1% pyrite tourmaline stringers, and 1% tourmaline in a moderately sericitized and slightly chloritized gabbro.
OSK-W-17-1187 intersected 3.43 g/t au over 2.7 metres in Lynx 3. Mineralization is composed of 6% pyrite clusters stringers with 1% tourmaline ptygmatic veins in a moderately chloritized gabbro with fuchsite.
OSK-W-17-1193 intersected 28.3 g/t Au over 7.7 metres in Lynx 4. High grade mineralization is composed of local visible gold, up 10% pyrite stringers in pervasive silica flooding hosted in a breccia unit with strong fuchsite and silica alteration. This unit is at a contact of a sericitized porphyric felsic dike containing trace pyrite stringers.
OSK-W-17-1193-W1 intersected 14.8 g/t Au over 4.4 metres in the Lynx 4 Corridor. High grade mineralization is composed 7% pyrite stringer and 1% chalcopyrite in 20-30% crustiform veins at low angles with quartz tourmaline veins hosted in gabbro with moderate fuchsite alteration.
OSK-W-17-1242 intersected 3.68 g/t Au over 2.5 metres, 4.38 /t Au over 2.0 metres and 43.8 g/t Au over 2.5 metres, all in Lynx 4. The first interval is composed of up to 5% tourmaline-pyrite stringers hosted in a strongly sericitized gabbro with fuchsite and rhyolite fragments. The second interval is composed of 5% pyrite in quartz-tourmaline veins with locally intense pervasive silica flooding hosted in a moderately sericitized rhyolite. High grade mineralization in the third interval is composed of local trace electrum in millimetre fracture fillings and 3% disseminated and stringer pyrite hosted in a strongly chloritized fragmental rhyolite.
OSK-W-17-1242-W2 intersected 7.18 g/t au over 2.0 metres related to the Lynx HW. Mineralization is composed of 4% pyrite clusters and 1% pyrite in quartz veins with patches of silica flooding. The interval is hosted in a fragmental rhyolite.
OSK-W-17-1320 intersected 4.72 g/t Au over 2.5 metres and 5.45 g/t Au over 2.0 metres in the southwest extension of Lynx 1 Corridor. The first interval is composed of 65% crustiform vein and 5% disseminated and stringer pyrite in a strongly silicified and fuchsitized andesite at the contact with porphyric felsic dike. The second interval is composed of 5% disseminated pyrite, 1% sphalerite clusters with intense and local pervasive silica flooding hosted in a porphyritic felsic dike with moderate carbonate and sericite alteration. It is located 90 metres south-west and up-plunge of OSK-W-17-1052 (7.65 g/t Au over 4.1 metres, previously reported October 30, 2017).
OSK-W-17-1343 intersected Lynx HW returning 140 g/t Au over 5.0 metres. High grade mineralization is composed of disseminated local visible gold in stringers filling up micro fractures with electrum in a smoky quartz vein. It is host in a moderate sericitized and silicified rhyolite.
OSK-W-17-1343-W2 intersected 34.1 g/t Au over 4.4 metres related to Lynx HW. Mineralization is composed of local visible gold and up to 10% pyrite with pervasive silica flooding hosted in a moderately silicified and sericitized fragmental felsic intrusive.
OSK-W-17-1346 intersected 3.26 g/t Au over 4.1 metres in Lynx 2. Mineralization is composed of 6% pyrite clusters and 2% pyrite stringers at the contact between a chloritized gabbro and a silica altered porphyritic felsic intrusion.
OSK-W-17-1350 intersected 6.31 g/t Au over 2.0 metres in Lynx 4. Mineralization is composed of 5% pyrite in a sericitized rhyolite in contact with andesite. The contact contains brecciated smoky quartz veins with sericite, carbonate, tourmaline and sulfides over 1.0 metres with local visible gold.
OSK-W-17-1356 intersected 10.0 g/t Au over 2.3 metres in Lynx 1. Mineralization is composed of 5% pyrite in low core angle ptygmatic tourmaline vein and 1% disseminated pyrite at the strongly epidotized, moderately sericitized rhyolite-gabbro contact.
OSK-W-17-1364 intersected 15.0 g/t Au over 6.1 metres in the south west extension of Lynx 1 corridor. Mineralization is at contact between a porphyric felsic dyke and andesite. The porphyric felsic dike is moderately silica and sericite altered with up to 5% disseminated and stringer pyrite with local and intense pervasive silica flooding and fuchsite. The andesite is moderately silicified and sericitized with 6% disseminated or stringer pyrite, and one-meter crustiform vein. It is located 110 metres at north-east and down-plunge of OSK-W-17-1052 (7.65 g/t Au over 4.1 metres, previously reported October 30, 2017).
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").
Quality Control and Reporting Protocols
True widths determinations are estimated at 65-80% of the reported core length intervals for most of the zones. Assays are uncut except where indicated. Intercepts occur within geological confines of major zones but have not been correlated to individual vein domains at this time. Reported intervals include minimum weighted averages of 3.0 g/t Au diluted over core lengths of at least 2.0 metres. All NQ core assays reported were obtained by either 1-kilogram screen fire assay or standard 50-gram fire-assaying-AA finish or gravimetric finish at ALS Laboratories in Val d'Or, Québec, Thunder Bay and Sudbury, Ontario or Vancouver, British Colombia or Bureau Veritas in Timmins, Ontario. The 1-kilogram screen assay method is selected by the geologist when samples contain coarse gold or present a higher percentage of pyrite than surrounding intervals. Selected samples are also analyzed for multi-elements, including silver, using an Aqua Regia-ICP-AES method at ALS Laboratories. Drill program design, Quality Assurance/Quality Control ("QA/QC") and interpretation of results is performed by qualified persons employing a QA/QC program consistent with NI 43-101 and industry best practices. Standards and blanks are included with every 20 samples for QA/QC purposes by the Corporation as well as the lab. Approximately 5% of sample pulps are sent to secondary laboratories for check assay.
About the Windfall Lake Gold Deposit
The Windfall Lake gold deposit is located between Val-d'Or and Chibougamau in the Abitibi region of Québec, Canada. The mineral resource defined by the previous operator comprises 2,762,000 tonnes at 8.42 g/t Au (748.000 ounces) in the indicated category and 3,512,000 tonnes at 7.62 g/t Au (860,000 ounces) in the inferred category (sourced from a technical report dated June 10, 2015 entitled "Preliminary Economic Assessment of the Windfall Lake Gold Property, Québec, Canada" with an effective date of April 28, 2015, prepared in accordance with NI 43-101). The Windfall Lake gold deposit is currently one of the highest grade resource-stage gold projects in Canada. The bulk of the mineralization occurs in the Main Zone, a southwest/northeast trending zone of stacked mineralized lenses, measuring approximately 600 metres wide and at least 1.400 metres long. The deposit is well defined from surface to a depth of 500 metres, and remains open along strike and at depth. Mineralization has been identified only 30 metres from surface in some areas and as deep as 870 metres in others, with significant potential to extend mineralization up and down-plunge and at depth.
About Osisko Mining Inc.
Osisko is a mineral exploration company focused on the acquisition, exploration, and development of precious metal resource properties in Canada. Osisko holds a 100% in the high-grade Windfall Lake gold deposit located between Val-d'Or and Chibougamau in Québec and holds a 100% undivided interest in a large area of claims in the surrounding Urban Barry area and nearby Quevillon area (over 3,300 square kilometres), a 100% interest in the Marban project located in the heart of Québec's prolific Abitibi gold mining district, and properties in the Larder Lake Mining Division in northeast Ontario, including the Jonpol and Garrcon deposits on the Garrison property, the Buffonta past producing mine and the Gold Pike mine property. The Corporation also holds interests and options in a number of additional properties in northern Quebec and Ontario. Osisko continues to be well financed with approximately $190 million in cash and investments.
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", "management's 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 management's 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.