Category: Silver / Gold

OSISKO EXPANSION DRILLING INTERSECTS HIGH GRADE AT WINDFALL

143 g/t Au Over 2.0 Metres in Lynx Extension
35 g/t Au Over 5.3 Metres in Triple Lynx
 
TORONTO, April 07, 2020 -- Osisko Mining Inc. (OSK:TSX. "Osisko" or the "Corporation") is pleased to provide new infill drilling results from the definition and expansion drill program at its 100% owned Windfall gold project located in the Abitibi greenstone belt, Urban Township, Eeyou Istchee James Bay, Québec.
 
Operations are temporarily suspended in respect of the Government of Québec’s closure of all non-essential business in effort to contain COVID-19. Osisko is ready to resume drilling activities at Windfall once the temporary suspension is lifted. Drilling will remain focused on the Lynx deposit, exploration on the main mineralized zones, and deep exploration in the central areas of the mineralized system.

Significant new analytical results are presented below and include 35 intercepts in 7 drill holes, 8 wedges and one extension of a previous drilled hole.  All intercepts reported below are located outside the February 2020 mineral resource estimate wireframes (see Osisko news release dated February 19, 2020) and represent expansion of known mineralized zones.

Selected high-grade intercepts include: 143 g/t Au over 2.0 metres and 64.4 g/t Au over 2.2 metres in OSK-W-19-2197-W1; 35.0 g/t Au over 5.3 metres in OSK-W-20-2123-W4; 39.8 g/t Au over 2.3 metres in OSK-W-20-2139-W6; and 37.3 g/t Au over 2.4 metres in WST-20-0339. Maps showing hole locations and full analytical results are available at www.osiskomining.com.

Hole No. From (m) To (m) Interval (m) Au (g/t) uncut Au (g/t)  cut to 100 g/t Zone Corridor
OSK-W-17-1258 1014.3 1023.1 8.8 9.72   Lynx 4 Lynx
including 1020.3 1021.3 1.0 49.6  
  1030.8 1033.1 2.3 5.68   Lynx 4 Lynx
including 1031.4 1031.9 0.5 25.8  
OSK-W-19-2123-W3 1002.0 1004.8 2.8 3.23   Triple Lynx Lynx
  1147.0 1149.4 2.4 4.30   Lynx_363 Lynx
including 1149.0 1149.4 0.4 13.9  
OSK-W-19-2197-W1 1047.8 1050.0 2.2 64.4 20.4 Lynx_374 Lynx
including 1048.6 1048.9 0.3 423 100
  1062.0 1064.0 2.0 143 45.4 Lynx_374 Lynx
including 1062.5 1063.4 0.9 317 100
OSK-W-19-2217 781.9 784.0 2.1 16.8   Triple Lynx Triple Lynx
including 782.6 783.0 0.4 78.9  
  791.6 793.6 2.0 3.11   Triple Lynx Triple Lynx
  905.5 908.0 2.5 8.61   Triple Lynx Triple Lynx
including 905.5 906.5 1.0 17.4  
  961.2 966.3 5.1 13.4   Triple Lynx Triple Lynx
including 963.7 964.2 0.5 98.4  
OSK-W-20-1072-W4 966.6 968.8 2.2 29.3   Lynx 4 Lynx 4
  1010.0 1012.0 2.0 11.5   Lynx 4 Lynx 4
including 1011.0 1012.0 1.0 20.6  
OSK-W-20-1272-W6 842.0 848.0 6.0 12.7   Triple Lynx Triple Lynx
  990.0 992.0 2.0 4.33   Lynx_370 Lynx
  997.8 1000.0 2.2 8.60   Triple Lynx Triple Lynx
including 999.0 999.5 0.5 28.1  
OSK-W-20-1731-W6 593.0 595.4 2.4 6.78   Lynx Lynx
including 593.5 593.8 0.3 21.3  
OSK-W-20-2100-W9 949.0 954.4 5.4 4.57   Triple Lynx Triple Lynx
OSK-W-20-2123-W4 1086.0 1088.0 2.0 4.00   Lynx 361 Lynx
  1096.0 1098.0 2.0 12.6   Triple Lynx Triple Lynx
  1128.0 1130.3 2.3 5.31   Triple Lynx Triple Lynx
  1177.2 1182.5 5.3 35.0 33.6 Triple Lynx Lynx
including 1177.5 1178.0 0.5 116 100
  1198.0 1200.0 2.0 8.07   Triple Lynx Triple Lynx
OSK-W-20-2139-W6 902.0 904.3 2.3 39.8 16.6 Triple Lynx Triple Lynx
including 902.4 902.7 0.3 278 100
  912.3 914.3 2.0 5.64   Triple Lynx Triple Lynx
including 913.6 913.9 0.3 34.5  
OSK-W-20-2243 789.6 792.0 2.4 19.4 18.4 Lynx_361 Lynx
including 790.2 790.5 0.3 108 100
  800.1 802.4 2.3 5.01   Triple Lynx Triple Lynx
WST-20-0337 102.5 104.6 2.1 4.69   Lynx Lynx
including 104.3 104.6 0.3 27.7  
WST-20-0339 55.0 57.5 2.5 5.43   Lynx Lynx
  93.0 95.4 2.4 37.3 32.3 Lynx_304 Lynx
including 93.5 94.1 0.6 120 100
  182.0 184.7 2.7 4.49   Lynx _321 Lynx
  191.2 194.3 3.1 5.35   Lynx _321 Lynx
WST-20-0340 62.0 64.5 2.5 6.79   Lynx Lynx
including 64.0 64.5 0.5 31.5  
WST-20-0365 90.4 93.0 2.6 9.78   Lynx Lynx
including 92.2 92.6 0.4 50.8  
WST-20-0372 189.2 191.5 2.3 7.73   Lynx HW Lynx
including 190.9 191.5 0.6 26.1  
  431.7 434.0 2.3 21.6   Lynx 4 Lynx 4
including 433.2 434.0 0.8 61.4  

Notes: True widths are estimated at 55 – 80% of the reported core length interval. See "Quality Control and Reporting Protocols" below.

Drill hole location

Hole Number Azimuth (°) Dip (°) Length (m) UTM E UTM N Elevation Section
OSK-W-17-1258 126 -51 1128 452972 5435211 416 3275
OSK-W-19-2123-W3 126 -57 1284 453231 5435774 400 3775
OSK-W-19-2197-W1 121 -48 1104 453087 5435527 418 3550
OSK-W-19-2217 134 -48 1172 452943 5435566 419 3425
OSK-W-20-1072-W4 145 -57 1092 453612 5435532 399 4000
OSK-W-20-1272-W6 127 -60 1035 453246 5435535 412 3675
OSK-W-20-1731-W6 139 -51 1068 453383 5435518 409 3800
OSK-W-20-2100-W9 122 -47 1074 453093 5435726 419 3650
OSK-W-20-2123-W4 126 -57 1236 453231 5435774 400 3775
OSK-W-20-2139-W6 115 -52 1089 452980 5435549 420 3450
OSK-W-20-2243 122 -54 815 453087 5435527 418 3550
WST-20-0337 145 -6 203 453411 5435230 114 3675
WST-20-0339 146 -18 295 453410 5435229 114 3675
WST-20-0340 147 -26 135 453410 5435229 114 3675
WST-20-0365 158 -8 142 453450 5435264 116 3725
WST-20-0372 148 -42 451 453493 5435287 116 3775

Lynx Zone
Mineralization in the Lynx zone is typically characterized by trace to 15% disseminated, clustered or stringer pyrite (locally up to 70%), local visible gold, trace to 3% sphalerite, chalcopyrite, and galena, local ptygmatic pyrite-tourmaline or tourmaline veinlets, quartz-carbonate veins (locally crustiform), smoky quartz veins and veinlets, and local chlorite-calcite or quartz-carbonate chlorite fracture filling. Alteration consists of weak to strong sericite, weak to strong silica with areas of local pervasive silica flooding, weak to moderate chlorite and carbonate, and locally weak to strong fuchsite. Mineralization is hosted in or at the contacts of felsic porphyritic or fragmental intrusions with rhyolites, andesites (locally bleached), or gabbros.

Triple Lynx Zone
Mineralization in the Triple Lynx zone is typically characterized by trace to 30% disseminated, clustered or stringer pyrite, local visible gold, trace sphalerite, chalcopyrite, and galena, local quartz-tourmaline veins (up to 20%), local ptygmatic tourmaline veins, and local smoky quartz and quartz-carbonate veins. Alteration consists of weak to strong sericite, weak to strong silica with areas of local pervasive silica flooding, weak to moderate chlorite and carbonate, and locally weak to strong fuchsite. Mineralization is hosted in or at the contacts of felsic porphyritic dikes with rhyolites (locally bleached) or gabbros.

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 Osisko's 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 width determination is estimated at 55-80% of the reported core length interval for the zone. 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 (i) ALS Laboratories in Val d'Or, Québec, Thunder Bay, Ontario, Sudbury, Ontario or Vancouver, British Colombia, or (ii) 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 Gold Deposit
The Windfall gold deposit is located between Val-d'Or and Chibougamau in Eeyou Istchee James Bay, Québec, Canada. The mineral resource defined by Osisko, as disclosed in the news release dated February 19, 2020, and assuming a cut-off grade of 3.5 g/t, comprises 4,127,000 tonnes at 9.1 g/t Au (1,206,000 ounces) in the indicated mineral resource category and 14,532,000 tonnes at 8.40 g/t Au (3,938,000 ounces) in the inferred mineral resource category. The key assumptions, parameters and methods used to estimate the mineral resource estimate disclosed in the February 19,2020 news release are further described in the full technical report in accordance with NI 43-101, available on SEDAR (www.sedar.com) under the Corporation's issuer profile. The Windfall gold deposit is currently one of the highest-grade resource-stage gold projects in Canada and has world-class scale. Mineralization occurs in three principal zones: Lynx, Main Zone, and Underdog.  Mineralization is generally comprised of sub-vertical zones following intrusive porphyry contacts plunging to the northeast. The deposit is well defined from surface to a depth of 1,200 metres and remains open along strike and at depth. Mineralization has been identified 30 metres from surface in some areas and as deep as 2,000 metres in others, with significant potential to extend mineralization 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% interest in the high-grade Windfall 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 Quévillon area (over 2,700 square kilometres).

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. Any statement that involves 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", "potential", "feasibility", "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 news release contains the forward-looking information pertaining to, among other things: the Windfall gold deposit being one of the highest-grade resource-stage gold projects in Canada and having world-class scale; the key assumptions, parameters and methods used to estimate the mineral resource estimate; the prospects, if any, of the Windfall gold deposit; timing and ability of Osisko to file a technical report for the mineral resource estimate; the timing and ability of Osisko, if at all, to publish a feasibility study for the Windfall gold deposit; the projected capital expenditures of mining activities at the Windfall gold deposit; upgrading an inferred mineral resource to a measured mineral resource or indicated mineral resource category; future drilling at the Windfall gold deposit; the deposit remaining open along strike to the northeast and at depth; significant high-grade zones (Lynx 4, Triple Lynx) remaining open down plunge; the plunge potential of the Lynx and Underdog zones; the significance of historic exploration activities and results. 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 and royalty interests in the Windfall gold deposit; the ability of the Corporation to obtain required approvals; 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.

CONTACT INFORMATION:
John Burzynski
President & Chief Executive Officer
Telephone (416) 363-8653