Osisko Mining Inc. ("Osisko" or the "Corporation") is pleased to announce new results from the ongoing drill program at its 100% owned Windfall Lake gold project located in Urban Township, Québec. The 55,000 metre drill program combines definition drilling above the Red Dog intrusion ("Red Dog") and expansion drilling above and below Red Dog.
Highlights from three new drill holes above Red Dog include: 30.6 g/t Au over 3.1 metres; 9.04 g/t Au over 5.8 metres; and 8.30 g/t Au over 3.0 metres in DDH OBM-16-656; and 178 g/t Au over 0.3 metres, 4.64 g/t Au over 10.2 metres and 7.34 g/t Au over 3.0 metres in DDH OBM-16-664. The new results continue to demonstrate lateral and vertical continuity of high grade gold mineralization in Zone 27 and the Caribou Zone. The table below outlines significant new results(1)(2):
Drill Hole Collar Coordinates and Information:
DDH OBM-16-656 tested the Caribou Zone and Zone 27 at 40 metres and 220 metres below surface respectively. Two parallel mineralized corridors were intersected in the Caribou Zone and returned 6.48 g/t gold over 2.1 metres and 6.19 g/t Au over 5.7 metres respectively. Both intercepts consist of up to 15 percent pyrite in stringers and dissemination. Zone 27 returned two parallel intercepts averaging 30.6 g/t Au over 3.1 metres and 8.30 g/t Au over 3.0 metres respectively, confirming the continuity of high grade material in this part of the deposit. DDH OBM-16-656 also intersected a pyritic stockwork within the hanging wall of Zone 27 which averaged 9.04 g/t Au over 5.8 metres.
DDH OBM-16-662 targeted the Caribou Zone at 125 meters below surface and intersected 3.09 g/t Au over 2.1 metres in an interval located within the hanging wall of the Caribou Zone. The Caribou Zone returned 0.95 g/t Au over 6.0 metres in a zone characterized by 5% pyrite stringers and silicification.
DDH OBM-16-664 intersected the Caribou Zone at 140 metres below surface and Zone 27 at 355 metres below surface. The Caribou Zone returned 7.3 g/t Au over 3.0 metres from an interval containing 8% pyrite in stringers and disseminations and also intersected a crustiform vein containing visible gold hosted in an altered felsic volcanic flow. Zone 27 returned 4.64 g/t Au over 10.2 metres at the contact between a porphyry dyke and an altered andesite containing 5% pyrite stringers and disseminations. The crustiform vein returned 178 g/t Au over 0.3 metres in the footwall of Zone 27.
The scientific and technical content of this press release has been reviewed by Mr. Jean-Philippe Desrochers, PhD, P.Geo. Senior Project Manager for Osisko at 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").
True widths are estimated at 65-80% of the reported core length intervals. 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 individual assays of 3.0 g/t Au and minimum weighted averages of 3.0 g/t Au averaged over core lengths of a minimum of 2 metres. All NQ core assays reported were obtained by either 1 kg screen fire assay or standard 50 gram fire-assaying-AA finish or gravimetric finish at ALS Laboratories in Val d'Or, Québec or Sudbury, Ontario. The 1 kg screen assay method is selected by the geologist when samples contain coarse gold or present a higher percentage of pyrite than surrounding intervals. All samples are also analysed for multi-elements, including silver, using an Aqua Regia-ICP-AES method at ALS laboratories. Drill program design, Quality Assurance/Quality Control 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 current mineral resource 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, Quebec, 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.