Category: Silver / Gold

Osisko Infill Drilling Continues to Confirm High Grade at Lynx

Including 376 g/t Au Over 2.0 Metres
And 35.2 g/t Au Over 4.3 Metres
 
TORONTO, June 23, 2020  -- Osisko Mining Inc. (OSK:TSX. "Osisko" or the "Corporation") is pleased to provide new drilling results from the ongoing 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.
 
Drilling is currently focused on the Lynx deposit, the main mineralized zones, and down plunge exploration in the central areas of the mineralized system.  Windfall camp is expected to return to full capacity with 21 drill rigs by the end of this week.
 
Osisko President and Chief Executive Officer John Burzynski commented: “Todays infill results continue to demonstrate the continuity of the high-grade values in Lynx and Triple Lynx, as we continue to intersect the zones where anticipated. The drill program remains focused on defining the Lynx deposit as well as targeting key areas up plunge and down plunge for growth potential.  We are also having good success in step-out drilling which will add to the scale of the deposit.”

Significant new analytical results from 33 intercepts in 18 drill holes and 7 wedges are presented below.

Selected high-grade intercepts from the new results include: 376 g/t Au over 2.0 metres in WST-20-0310; 23.8 g/t Au over 6.2 metres in OSK-W-19-2100-W5; 35.2 g/t Au over 4.3 metres in WST-20-0380; and 27.0 g/t Au over 4.5 metres in OSK-W-20-2250.  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-19-1731-W4 534.7 539.6 4.9 7.76   Lynx_304 Lynx
including 534.7 535.2 0.5 36.5  
and 538.9 539.6 0.7 17.6  
OSK-W-19-2100-W5 962.0 968.2 6.2 23.8 20.3 Lynx_361 Triple Lynx
including 966.2 966.8 0.6 136 100
OSK-W-19-2204 69.4 71.5 2.1 4.85   Lynx_304 Lynx
including 70.8 71.5 0.7 14.2  
OSK-W-20-1104-W7 470.0 472.0 2.0 7.98   Lynx_359 Lynx
including 470.7 471.2 0.5 29.4  
OSK-W-20-2139-W7 867.0 869.0 2.0 4.41   Lynx_361 Triple Lynx
including 867.8 868.2 0.4 12.5  
  872.0 874.8 2.8 3.09   Lynx_361 Triple Lynx
  894.0 896.6 2.6 3.01   Lynx_363 Triple Lynx
including 895.0 895.3 0.3 24.5  
  899.4 901.7 2.3 3.06   Lynx_363 Triple Lynx
OSK-W-20-2243-W1 828.1 833.3 5.2 5.43   Lynx_364 Triple Lynx
including 828.1 828.4 0.3 40.6  
OSK-W-20-2243-W2 828.0 834.0 6.0 2.99   Lynx_363 Triple Lynx
OSK-W-20-2245 109.5 111.5 2.0 15.2   Lynx_311 Lynx
including 110.6 110.9 0.3 91.6  
OSK-W-20-2250 799.5 804.0 4.5 27.0 14.7 Lynx_364 Triple Lynx
including 799.5 799.8 0.3 134 100
and 801.5 801.8 0.3 251 100
  807.0 809.0 2.0 5.87   Lynx_364 Triple Lynx
OSK-W-20-2250-W1 767.0 769.0 2.0 5.65   Lynx_363 Triple Lynx
OSK-W-20-2252 871.1 873.6 2.5 3.21   Lynx_371 Triple Lynx
including 871.1 872.0 0.9 7.51  
  875.3 877.7 2.4 4.09   Lynx_371 Triple Lynx
including 876.3 877.0 0.7 10.6  
WST-20-0309 58.0 60.5 2.5 14.0   Lynx_311 Lynx
including 58.5 59.5 1.0 34.8  
WST-20-0310 63.7 65.7 2.0 376 34.4 Lynx_311 Lynx
including 63.7 64.2 0.5 1465 100
WST-20-0311 54.0 56.1 2.1 5.75   Lynx_311 Lynx
  57.9 60.3 2.4 9.84   Lynx_311 Lynx
including 59.8 60.3 0.5 35.8  
WST-20-0317 57.8 60.0 2.2 3.47   Lynx_311 Lynx
including 58.7 59.2 0.5 14.2  
  64.4 66.4 2.0 13.7   Lynx_323 Lynx
including 65.4 66.4 1.0 26.8  
WST-20-0319 58.7 62.3 3.6 23.6 21.1 Lynx_323 Lynx
including 60.5 60.9 0.4 122 100
and 61.9 62.3 0.4 80.5  
WST-20-0320 73.0 75.6 2.6 15.5   Lynx_323 Lynx
including 74.9 75.6 0.7 44.5  
WST-20-0380 52.9 57.2 4.3 35.2 30.4 Lynx_311 Lynx
including 56.2 57.2 1.0 121 100
WST-20-0384 125.0 127.0 2.0 25.5   Lynx_304 Lynx
including 125.0 125.4 0.4 62.8  
and 126.5 127.0 0.5 50.0  
WST-20-0417 65.0 67.5 2.5 4.81   Lynx_339 Lynx
WST-20-0428 130.5 132.8 2.3 3.40   Lynx_304 Lynx
including 131.5 132.2 0.7 9.97  
WST-20-0430 124.7 127.0 2.3 15.7   Lynx_359 Lynx
including 125.1 125.5 0.4 88.8  
WST-20-0432 126.0 128.0 2.0 9.25   Lynx_359 Lynx
including 126.0 126.4 0.4 43.7  
WST-20-0433A 117.0 119.1 2.1 7.84   Lynx_304 Lynx
including 117.6 117.9 0.3 36.1  
  122.0 124.0 2.0 10.9   Lynx_359 Lynx
including 122.9 123.4 0.5 39.1  
WST-20-0434 114.0 116.6 2.6 8.28   Lynx_304 Lynx
including 114.0 114.6 0.6 32.1  

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-19-1731-W4 139 -51 975 453383 5435518 409 3800
OSK-W-19-2100-W5 122 -47 1134 453095 5435726 423 3650
OSK-W-19-2204 326 -46 143 453254 5434979 398 3425
OSK-W-20-1104-W7 142 -50 867 453383 5435455 402 3775
OSK-W-20-2139-W7 115 -52 1164 452980 5435549 420 3450
OSK-W-20-2243-W1 122 -54 960 453087 5435527 418 3550
OSK-W-20-2243-W2 122 -54 972 453087 5435527 418 3550
OSK-W-20-2245 321 -49 153 453236 5434971 398 3400
OSK-W-20-2250 132 -57 1064 453128 5435505 420 3575
OSK-W-20-2250-W1 132 -57 1060 453128 5435505 420 3575
OSK-W-20-2252 129 -54 1194 453241 5435694 415 3750
WST-20-0309 172 -23 166 453292 5435139 163 3525
WST-20-0310 169 -33 97 453292 5435139 163 3525
WST-20-0311 152 -15 97 453292 5435140 163 3525
WST-20-0317 131 -23 127 453292 5435140 163 3525
WST-20-0319 134 -3 118 453293 5435140 163 3525
WST-20-0320 128 -16 124 453293 5435140 163 3525
WST-20-0380 159 11 85 453228 5435126 136 3475
WST-20-0384 160 -35 157 453493 5435286 116 3775
WST-20-0417 138 -50 759 453228 5435126 134 3475
WST-20-0428 143 -37 232 453493 5435287 116 3775
WST-20-0430 160 -29 148 453493 5435287 117 3775
WST-20-0432 149 -32 157 453450 5435264 115 3725
WST-20-0433A 155 -32 157 453450 5435264 115 3725
WST-20-0434 156 -28 154 453450 5435264 115 3725

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 supported by the technical report entitled “An updated mineral resource estimate for the Windfall Lake Project, Located in the Abitibi Greenstone Belt, Urban Township, Eeyou Istchee James Bay, Québec, Canada” and dated April 3, 2020 (with an effective date of January 3, 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 prepared by Micon International Limited ("Micon") and BBA Inc ("BBA"), 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; 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