Osisko Windfall Infill Drilling Adds Wide High-Grade

Including 293 g/t Au Over 11.0 Metres


TORONTO, June 07, 2022 (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 15 underground drill holes and 12 wedges. The infill intercepts are located inside defined January 2022 mineral resource estimate (“MRE”) blocks (see Osisko news release dated January 10, 2022). The expansion intercepts are located outside the January 2022 MRE blocks and either expand resource wireframes or are in a defined zone or corridor but do not yet correlate to a specific wireframe.

Osisko Chief Executive Officer John Burzynski commented: “Lynx continues to return wide high-grade intercepts which will be included in the upcoming feasibility study. Our headline hole, with an estimated true thickness of eight meters, and other holes with sub-intervals over a kilogram of gold per tonne, demonstrate the robust nature of the high-grade areas in the Lynx 4 and Triple Lynx zones.”

Selected high-grade intercepts include: 293 g/t Au over 11.0 metres in OSK-W-22-2605-W6, 199 g/t Au over 2.9 metres in OSK-W-22-2587-W6; 24.3 g/t Au over 13.4 metres in OSK-W-22-2587-W5; 73.4 g/t Au over 2.3 metres in WST-22-1041B and 54.9 g/t Au over 3.0 metres in WST-22-1046B. Maps showing hole locations and full analytical results are available at www.osiskomining.com.

Maps: Long Section_All zones In EN 20220607, Long Section_All zones Ex EN 20220607, PR_EN_20220607_Surface, PR_EN_20220607_UG.

Infill Drilling

Hole No.From
(m)
To
(m)
Interval
(m)
Au (g/t)
uncut
Au (g/t)
cut to
100 g/t
ZoneCorridor
OSK-W-22-2587-W41084.41093.79.35.67 TLX_3155
Triple Lynx
including1088.51088.90.426.9 
OSK-W-22-2587-W51040.51043.02.58.52 TLX_3158
Triple Lynx
including1040.51040.90.441.0 
 1052.41055.02.64.30 TLX_3158
Triple Lynx
including1052.41052.80.418.9 
 1110.01112.12.18.85 TLX_3162
Triple Lynx
including1110.71111.10.432.9 
 1120.71125.44.74.54 TLX_3162
Triple Lynx
including1125.01125.40.423.6 
 1129.01131.02.08.25 TLX_3162Triple Lynx
 1136.31149.713.424.314.6TLX_3172
Triple Lynx
including1141.31142.31.0129100
and1142.31142.80.5302100
OSK-W-22-2587-W61122.01126.04.015.315.0TLX_3162
Triple Lynx
including1122.01122.40.4104100
 1134.61141.26.610.3 TLX_3162
Triple Lynx
including1134.61135.20.633.8 
 1149.11152.02.919931.0TLX_3172
Triple Lynx
including1149.11149.60.5423100
and1150.11150.40.31185100
OSK-W-22-2601-W51011.01013.62.637.5 TLX_3158
Triple Lynx
including1011.71012.10.495.5 
OSK-W-22-2605-W41301.21303.42.25.95 LX4_3449
Lynx 4
including1302.51302.80.331.0 
OSK-W-22-2605-W61316.41327.411.029332.3LX4_3449
Lynx 4
including1317.41320.73.396192.3
with1318.81319.10.33040100
with1319.91320.20.35400100
OSK-W-22-2646-W71066.01070.14.15.06 TLX_3158
Triple Lynx
including1069.81070.10.330.6 
WST-21-0929A191.0193.22.220.0 TLX_3161
Triple Lynx
including192.4192.90.578.5 
WST-22-1014-W1257.0259.02.040.7 LXM_3367
Lynx
including257.0258.01.081.2 
WST-22-1017455.8459.53.76.76 LX4_3401
Lynx 4
including456.1456.50.419.2 
WST-22-1022403.0405.02.04.59 TLX_3162Triple Lynx
WST-22-1023204.0206.12.127.2 TLX_3121
Triple Lynx
including205.2206.10.961.1 
 566.0571.15.110.2 LX4_3404
Lynx 4
including567.0567.30.354.9 
WST-22-1031A449.0451.02.07.47 LX4_3401
Lynx 4
including450.2450.70.519.4 
 499.6503.13.54.52 LX4_3457
Lynx 4
including499.6500.10.513.0 
and502.7503.10.417.5 
WST-22-1041B526.8529.12.373.461.1LX4_3430
Lynx 4
including528.4528.70.3143100
WST-22-1043330.7332.72.06.19 TLX_3131
Triple Lynx
including330.7331.00.320.6 
WST-22-1045291.5293.72.229.8 TLX_3158
Triple Lynx
including291.5291.80.356.5 
WST-22-1046B315.0318.03.054.941.8TLX_3158
Triple Lynx
including315.0315.60.6157100
WST-22-1047138.0140.12.15.46 LXM_3345Lynx
WST-22-1048111.3113.62.332.2 LXM_3314
Lynx
including112.7113.20.595.2 
WST-22-105466.068.32.312.8 LXM_3388
Lynx
including67.467.90.534.3 
WST-22-1058C339.3344.75.410.6 TLX_3158
Triple Lynx
including339.3339.90.641.2 
WST-22-106099.6102.12.519.4 TLX_3121
Triple Lynx
including100.9101.20.366.9 
WST-22-1062153.6156.02.435.6 TLX_3121
Triple Lynx
including155.0156.01.066.8 

Notes: True widths are estimated at 55 – 80% of the reported core length interval. See "Quality Control and Reporting Protocols" below., LXM = Lynx Main, LX4 = Lynx 4 and TLX = Triple Lynx.

Expansion Drilling

Hole No.From
(m)
To
(m)
Interval
(m)
Au (g/t)
uncut
Au (g/t)
cut to
100 g/t
ZoneCorridor
OSK-W-22-2587-W31101.81104.72.917.8 TLXTriple Lynx
OSK-W-22-2587-W51094.31096.72.48.91 TLX
Triple Lynx
including1096.31096.70.436.9 
OSK-W-22-2587-W61104.01106.02.09.11 TLX
Triple Lynx
including1104.31104.70.438.5 
OSK-W-22-2601-W61096.21099.12.93.97 TLX_3162
Triple Lynx
including1096.51096.90.413.9 
OSK-W-22-2605-W41377.11379.12.06.74 LX4
Lynx 4
including1378.01378.70.714.2 
OSK-W-22-2646-W61069.71072.42.730.6 TLX_3158
Triple Lynx
including1070.11070.50.472.0 
and1071.01071.40.475.8 
 1190.11194.24.116.1 TLX_3172
Triple Lynx
including1190.11190.80.758.1 
OSK-W-22-2646-W71110.41112.52.18.53 TLX
Triple Lynx
including1111.71112.00.357.1 
OSK-W-22-2646-W81165.01167.32.37.79 TLX_3162
Triple Lynx
including1166.01166.30.338.8 
 1220.21222.32.19.82 TLX_3172
Triple Lynx
including1220.21221.00.823.2 
WST-22-1017467.0469.02.07.03 LX4
Lynx 4
including468.0469.01.012.4 

Notes: True widths are estimated at 55 – 80% of the reported core length interval. See "Quality Control and Reporting Protocols" below., LX4 = Lynx 4 and TLX = Triple Lynx.

Drill hole location

Hole No.Azimuth
(°)
Dip
(°)
Length
(m)
UTM EUTM NElevationSection
OSK-W-22-2587-W3127-59122145335054356734133850
OSK-W-22-2587-W4127-59121845335054356734133850
OSK-W-22-2587-W5127-59122745335054356734133850
OSK-W-22-2587-W6127-59120345335054356734133850
OSK-W-22-2601-W5125-61121545342554356564123900
OSK-W-22-2601-W6125-61121245342554356564123900
OSK-W-22-2605-W4112-55142545355154356694084025
OSK-W-22-2605-W6112-55140445355154356694084025
OSK-W-22-2646-W6109-58126345332654356484143800
OSK-W-22-2646-W7109-58122745332654356484143800
OSK-W-22-2646-W8109-58125445332654356484143800
WST-21-0929A117-453794535065435326-903800
WST-22-1014-W1123-375944535075435332-473800
WST-22-1017138-265614533445435312-663650
WST-22-1022132-624794535105435330-1273800
WST-22-1023120-486464535065435326-903800
WST-22-1031A136-285774533445435312-663650
WST-22-1041B127-435854535075435331-483800
WST-22-1043133-265614533445435312-663650
WST-22-1045104-543394537025435376-1984000
WST-22-1046B125-584364535105435331-1273800
WST-22-1047130-122264536475435347-1873950
WST-22-1048139-11694536475435347-1873950
WST-22-1054120-291964536475435347-1883950
WST-22-1058C121-605204535115435331-1273825
WST-22-1060140-551564536015435325-1813900
WST-22-1062144-591714536015435325-1813900

Lynx Zone
Mineralization occurs as grey to translucent quartz-carbonate-pyrite-tourmaline veins and pyrite replacement zones and stockworks. Vein-type mineralization is associated with haloes of pervasive sericite-pyrite ± silica alteration and contain sulphides (predominantly pyrite with minor amounts of chalcopyrite, sphalerite, galena, arsenopyrite, and pyrrhotite) and local visible gold. Replacement mineralization is associated with strong pervasive silica-sericite-ankerite ± tourmaline alteration and contains disseminated pyrite from trace to 80% with local visible gold. Pyrite stockworks can form envelopes that reach several tens of metres thick. Fuchsite alteration is common and is spatially constrained to near the gabbros. Mineralization occurs at or near geological contacts between felsic porphyritic or fragmental intrusions and the host rhyolites or gabbros and locally can be hosted along the gabbro-rhyolite contact.

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 3.5 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 Estimate (MRE) defined by Osisko, as disclosed in the news release dated January 10, 2022 is supported by the technical report entitled “Mineral Resource Estimate Update for the Windfall Project” dated February 10, 2022 (with an effective date  of October 21, 2021), and assuming a cut-off grade of 3.50 g/t Au, comprises 565,000 tonnes at 11.6 g/t Au (210,000 ounces) in the measured mineral resource category, 8,907,000 tonnes at 10.5 g/t Au (2,994,000 ounces) in the indicated mineral resource category and 13,035,000 tonnes at 8.6 g/t Au (3,585,000 ounces) in the inferred mineral resource category. The key assumptions, parameters and methods used to estimate the mineral resource estimate disclosed in the January 10, 2022, news release, certain of which are described in the January 10, 2022, news release, are further described in the full technical report for this updated mineral resource estimate 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 2,500 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