Osisko Drilling at Windfall Returns Near Surface High-Grade

Osisko Drilling at Windfall Returns Near Surface High-Grade

TORONTO, April 13, 2021 (GLOBE NEWSWIRE) — Osisko Mining Inc. (OSK:TSX. “Osisko” or the “Corporation”) is pleased to provide new analytical results from the ongoing drill program at its 100% owned Windfall gold project located in the Abitibi greenstone belt, Urban Township, Eeyou Istchee James Bay, Québec.

Significant new analytical results presented below include 43 intercepts in 18 drill holes (13 from surface, 5 from underground) and 6 wedges. The infill intercepts are located inside defined February 2021 mineral resource estimate (“MRE”) blocks (see Osisko news release dated February 17, 2021). The expansion intercepts are located outside the February 2021 mineral resource estimate (“MRE”) and either expand resource wireframes or are located in a defined zone or corridor but do not yet correlate to a specific wireframe.

Osisko Chief Executive Officer John Burzynski commented: “All zones at Windfall continue to expand and infill nicely with respect to the February 2021 MRE blocks, and continue to highlight the potential to increase the strong base case economics from the Windfall PEA, released last week.”

Selected high-grade intercepts include: 877 g/t Au over 2.2 metres and 85.0 g/t Au over 2.0 metres in WST-21-0668; 72.2 g/t Au over 2.0 metres in OSK-W-21-2442; 53.3 g/t Au over 2.3 metres in WST-21-0600; and 50.5 g/t Au over 2.4 metres in OSK-W-21-2442-W1. Maps showing hole locations and full analytical results are available at www.osiskomining.com

Infill Drilling

Hole No. From (m) To (m) Interval (m) Au (g/t) uncut Au (g/t) cut to 100 g/t Zone Corridor
OSK-W-20-2423 938.0 940.0 2.0 4.71   Underdog_4102 Underdog
including 939.5 940.0 0.5 16.6  
OSK-W-21-2442 627.0 629.0 2.0 17.4   Underdog_4100 Underdog
including 628.0 629.0 1.0 34.5  
  632.0 634.0 2.0 14.3   Underdog_4100 Underdog
including 632.4 633.0 0.6 36.7  
  642.0 644.0 2.0 24.7   Underdog_4100 Underdog
including 643.0 644.0 1.0 48.3  
  659.0 661.0 2.0 5.31   Underdog_4102 Underdog
including 659.0 659.5 0.5 12.9  
  667.0 669.0 2.0 72.2 57.5 Underdog_4102 Underdog
including 667.0 668.0 1.0 130 100
  686.0 688.0 2.0 17.6   Underdog_4104 Underdog
including 686.0 687.0 1.0 34.3  
  826.0 828.0 2.0 35.9 30.0 Underdog_4905 Underdog
including 826.8 827.4 0.6 120 100
OSK-W-21-2442-W1 696.0 698.0 2.0 3.48   Underdog_4104 Underdog
including 696.7 697.1 0.4 11.2  
  747.6 750.0 2.4 50.5 41.7 Underdog_4106 Underdog
including 749.0 750.0 1.0 121 100
  762.6 764.8 2.2 5.02   Underdog_4107 Underdog
including 762.6 762.9 0.3 34.8  
  854.6 857.0 2.4 5.10   Underdog_4905 Underdog
OSK-W-21-2455 697.0 699.0 2.0 20.4   Caribou_2220 Caribou
including 698.0 699.0 1.0 40.5  
OSK-W-21-2463 629.0 631.0 2.0 7.21   Caribou_2206 Caribou
OSK-W-21-2483 521.0 526.5 5.5 3.94   Caribou_2210 Caribou
including 521.0 522.0 1.0 11.2  
  547.0 549.3 2.3 11.2   Caribou_2215 Caribou
including 548.4 549.0 0.6 29.4  
WST-21-0600 160.0 162.3 2.3 53.3   Bobcat_2350 Bobcat
including 160.0 161.0 1.0 86.3  
WST-21-0668 36.5 38.7 2.2 877 19.1 Bobcat_2350 Bobcat
including 36.5 36.9 0.4 4820 100
WST-21-0669 74.0 76.0 2.0 11.5   Bobcat_2354 Bobcat

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

Expansion Drilling

Hole No. From (m) To (m) Interval (m) Au (g/t) uncut Au (g/t) cut to 100 g/t Zone Corridor
OSK-W-20-2374 102.3 104.4 2.1 3.16   Bobcat Bobcat
including 103.9 104.4 0.5 7.98  
OSK-W-20-2388 172.6 174.7 2.1 4.32   Caribou Caribou
OSK-W-20-2399-W2 405.0 407.1 2.1 6.93   Caribou Caribou
OSK-W-20-2405-W1 489.3 491.5 2.2 3.45   Caribou Caribou
including 490.9 491.5 0.6 9.86  
OSK-W-20-2410-W2 430.6 433.9 3.3 3.80   Caribou Caribou
including 433.6 433.9 0.3 14.6  
OSK-W-20-2415 467.0 469.0 2.0 4.57   Caribou Caribou
OSK-W-20-2425 181.2 184.1 2.9 3.65   Caribou Caribou
  190.1 192.2 2.1 6.18   Caribou Caribou
OSK-W-20-2430 70.8 73.0 2.2 5.59   F11 F11
OSK-W-20-2433 116.0 118.2 2.2 5.85   F11 F11
OSK-W-21-2442 916.3 918.4 2.1 3.51   Underdog Underdog
including 916.6 917.3 0.7 9.39  
  934.0 937.3 3.3 7.33   Underdog_4501 Underdog
including 935.0 935.5 0.5 18.3  
OSK-W-21-2442-W1 661.2 664.0 2.8 3.57   Underdog Underdog
  666.0 668.0 2.0 3.39   Underdog Underdog
OSK-W-21-2460-W1 759.0 761.0 2.0 4.39   Z27 Zone 27
OSK-W-21-2462-W1 655.0 657.0 2.0 6.97   Caribou Caribou
  682.0 684.0 2.0 4.37   Caribou Caribou
OSK-W-21-2476 572.6 574.8 2.2 10.7   Caribou Caribou
OSK-W-21-2490 712.0 714.0 2.0 4.35   Caribou Caribou
  732.0 734.3 2.3 8.52   Caribou Caribou
including 732.7 733.5 0.8 18.0  
WST-20-0480B 138.1 140.8 2.7 25.3   Z27 Zone 27
including 139.0 140.0 1.0 53.5  
WST-20-0559A 118.0 120.3 2.3 3.68   Bobcat Bobcat
WST-21-0668 95.0 97.0 2.0 85.0 20.0 Bobcat Bobcat
including 95.8 96.2 0.4 425 100
WST-21-0669 64.9 66.9 2.0 4.36   Bobcat Bobcat

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-20-2374 340 -52 138 452720 5434747 397 2850
OSK-W-20-2388 326 -61 699 452715 5434606 397 2775
OSK-W-20-2399-W2 333 -54 876 452875 5434553 398 2875
OSK-W-20-2405-W1 332 -58 716 452694 5434440 401 2675
OSK-W-20-2410-W2 338 -62 774 452727 5434358 402 2650
OSK-W-20-2415 328 -54 755 452739 5434475 401 2725
OSK-W-20-2423 332 -60 1326 452616 5434449 403 2600
OSK-W-20-2425 336 -60 747 452715 5434606 397 2775
OSK-W-20-2430 150 -45 360 452601 5436048 404 3375
OSK-W-20-2433 148 -47 411 452559 5436072 405 3350
OSK-W-21-2442 347 -53 1053 452315 5434419 399 2325
OSK-W-21-2442-W1 347 -53 1011 452315 5434419 399 2325
OSK-W-21-2455 328 -53 780 452738 5434476 401 2725
OSK-W-21-2460-W1 332 -55 795 452732 5434536 399 2750
OSK-W-21-2462-W1 338 -57 855 452875 5434553 398 2875
OSK-W-21-2463 339 -65 1335 452616 5434449 403 2600
OSK-W-21-2476 337 -58 879 452840 5434569 398 2850
OSK-W-21-2483 328 -58 756 452731 5434634 397 2800
OSK-W-21-2490 338 -61 786 452756 5434465 401 2725
WST-20-0480B 143 -51 382 452281 5434975 262 2575
WST-20-0559A 143 3 145 452955 5435003 254 3175
WST-21-0600 97 -20 172 452819 5434944 274 3025
WST-21-0668 142 -20 148 452817 5434943 274 3025
WST-21-0669 140 -4 142 452817 5434944 274 3025

Caribou Zone
Mineralization most commonly occurs in gold-bearing pyrite stockworks as well as semi-massive pyrite replacement zones associated with phyllic alteration (sericite-pyrite ± silica) with sulphides, pyrite dominated with minor chalcopyrite and sphalerite ranging from trace to up to 20%, and local visible gold. Mineralization is hosted in rhyolites or mafic-intermediate volcanics frequently at or near faults or the contact with felsic porphyritic intrusions.

Zone 27
Mineralization most commonly occurs as replacement-type characterized by 5% to 50% disseminated, stringer, semi-massive or stockwork pyrite, ptygmatic tourmaline veins, quartz-tourmaline crustiform veins, local quartz-carbonate veins, and local visible gold. Mineralization is associated with moderate to strong sericite, weak to strong silica, weak chlorite and carbonate and locally weak fuchsite and is hosted in strongly altered andesites, in or at the contact of the rhyolite, or along the contacts with felsic porphyritic intrusions.

F-Zone
Mineralization is hosted in sheared andesites with carbonate replacement or quartz veining and occurs as quartz ± ankerite veinlets or as replacement type in shear zones and is characterised by trace to 10% pyrite with local visible gold. Alteration is dominated by sericite-fuchsite-tourmaline-pyrite.

Bobcat
Mineralization most commonly occurs in gold-bearing quartz-pyrite veins controlled by northeast trending faults and shears and to a lesser extent in minor crustiform quartz-tourmaline-ankerite-pyrite veins and pyrite replacement zones and stockwork. Mineralization is hosted in sheared mafic volcanics, rhyolites near faults, or at the contact with felsic porphyritic intrusions.

Underdog
Mineralization most commonly occurs in gold-bearing quartz-pyrite (± tourmaline) veins and as disseminated, stringer, semi-massive to massive pyrite with minor sphalerite, chalcopyrite and molybdenite associated with strong sericite and silica alteration. Mineralization is hosted along the intrusive contacts of a three-phase composite felsic porphyritic unit which cross-cuts felsic and mafic volcanic sequences.

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), Director of Exploration for Osisko’s Windfall 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. NQ core assays 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, Vancouver, British Colombia, Lima, Peru or Vientiane, Laos (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 a Four Acid Digestion-ICP-MS 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 the Abitibi region of Québec, Canada. The mineral resource defined by Osisko, as disclosed in the news release dated February 17, 2021 and supported by the technical report entitled “Mineral Resource Estimate Update for the Windfall Project, Eeyou Istchee James Bay, Québec, Canada” dated March 8, 2021 (with an effective date of November 30, 2020), and assuming a cut-off grade of 3.50 g/t Au, comprises 521,000 tonnes at 11.3 g/t Au (189,000 ounces) in the measured mineral resource category, 5,502,000 tonnes at 9.4 g/t Au (1,668,000 ounces) in the indicated mineral resource category and 16,401,000 tonnes at 8.0 g/t Au (4,244,000 ounces) in the inferred mineral resource category. The key assumptions, parameters and methods used to estimate the mineral resource estimate disclosed in the February 17, 2021 news release are further described in the full technical report prepared by BBA Inc. in accordance with NI 43-101 and is 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 resources are defined from surface to a depth of 1,600 metres as it now includes the Triple 8 (T8) zone. The resources excluding T8 are defined from surface to a depth of 1,200 metres. The deposit remains open along strike and at depth. Mineralization has been identified at surface in some areas and as deep as 2,625 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 gold 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 disclosed in this news release; the prospects, if any, of the Windfall gold deposit; timing and ability of Osisko to file a technical report for the mineral resource estimate disclosed in this news release; the timing and ability of Osisko, if at all, to publish a feasibility study for the Windfall gold deposit; the amount and type of drilling to be completed and the timing to complete such drilling; the focus of the remaining infill drilling; the trend of grade increase; the Lynx zone remaining open to expansion down plunge; upgrading a inferred mineral resource to a measured mineral resource or indicated mineral resource category; future drilling at the Windfall gold deposit; 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 (infill) 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
Chief Executive Officer
Telephone (416) 363-8653

CBJ Newsmakers

Recommended
Solstice Gold Triples Its Red Lake Position with Three New ProjectsSYSPRO rebrands as it commits to securing a digital future for global manufacturers and distributors