SI
SI
discoversearch

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor.  We ask that you disable ad blocking while on Silicon Investor in the best interests of our community.  If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.
Gold/Mining/Energy : Mining News of Note -- Ignore unavailable to you. Want to Upgrade?


To: LoneClone who wrote (161706)12/3/2021 1:24:55 PM
From: LoneClone  Read Replies (1) | Respond to of 192748
 
Osisko Mining's Windfall Drilling Continues to Intercept High-Grade Across the Windfall Deposit

ca.finance.yahoo.com

Osisko Mining Inc.
Thu., December 2, 2021, 1:15 p.m.·22 min read

576 g/t Au over 2.7 metres in Triple Lynx

93.1 g/t Au over 3.0 metres in Caribou

22.3 g/t Au over 4.4 metres in Underdog

TORONTO, Dec. 02, 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 135 intercepts in 37 drill holes (18 from surface, 19 from underground) and 22 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 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: “Though the main infill drill campaign at Windfall has been successfully completed in support of the upcoming mineral resource estimate update, we continue with targeted infill and expansion drilling. Today’s results are part of this continuing program and clearly demonstrate Windfall’s growth upside, especially the expansion results.”

Selected high-grade intercepts include: 576 g/t Au over 2.7 metres, 17.6 g/t Au over 10.6 metres and 15.7 g/t Au over 8.1 metres in OSK-W-21-2587; 221 g/t Au over 2.0 metres in WST-21-0877; 127 g/t Au over 2.6 metres in OSK-W-21-2537-W3; 93.1 g/t Au over 3.0 metres in OSK-W-21-2606; 28.6 g/t Au over 4.9 metres in OSK-W-21-2540-W4; 34.7 g/t Au over 3.8 metres in OSK-W-21-1963-W8; 37.4 g/t Au over 3.0 metres in OSK-W-21-1963-W7, 15.4 g/t Au over 6.8 metres in WST-21-0857A and 22.3 g/t Au over 4.4 metres in OSK-W-21-2532-W3. 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-21-1949-W11

1047.2

1049.6

2.4

3.57


LX4_3430

Lynx 4


1053.6

1059.0

5.4

5.31


LX4_3434

Lynx 4

OSK-W-21-1963-W7

1331.6

1334.6

3.0

37.4


LX4_3449

Lynx 4

including

1331.6

1332.3

0.7

99.1



1345.0

1347.0

2.0

4.96


LX4_3445

Lynx 4

including

1345.6

1346.2

0.6

13.1



1374.0

1376.0

2.0

19.8


LX4_3445

Lynx 4

including

1374.7

1375.4

0.7

38.8



1378.8

1382.5

3.7

6.39


LX4_3445

Lynx 4

OSK-W-21-1963-W8

1340.7

1344.5

3.8

34.7

26.1

LX4_3449

Lynx 4

including

1341.6

1342.1

0.5

166

100

OSK-W-21-2287-W7

1138.0

1140.2

2.2

4.78


LX4_3453

Lynx 4

including

1139.6

1140.2

0.6

16.5



1219.8

1222.0

2.2

6.56


LX4_3449

Lynx 4

including

1220.3

1221.0

0.7

19.7


OSK-W-21-2287-W9

1237.2

1239.4

2.2

6.50


LX4_3449

Lynx 4

OSK-W-21-2400-W1

672.0

674.0

2.0

3.63


CA1

Caribou

including

672.4

672.7

0.3

23.1



762.0

764.0

2.0

4.43


CA2_2208

Caribou


820.0

822.3

2.3

4.03


CA2_2218

Caribou

OSK-W-21-2416-W7

939.9

944.0

4.1

9.01


TLX_3161

Triple Lynx

including

940.3

941.0

0.7

24.2



966.6

969.0

2.4

9.84


TLX_3163

Triple Lynx


985.0

987.1

2.1

8.85


TLX_3163

Triple Lynx

including

986.0

986.3

0.3

36.3



1006.0

1008.1

2.1

6.21


TLX_3164

Triple Lynx

including

1007.8

1008.1

0.3

35.5



1051.5

1053.5

2.0

20.2


TLX_3170

Triple Lynx


1086.0

1089.0

3.0

4.33


TLX_3172

Triple Lynx


1096.0

1098.2

2.2

7.08


TLX_3193

Triple Lynx

including

1097.1

1097.6

0.5

21.4


OSK-W-21-2479-W10

464.0

466.0

2.0

4.52


Z27_1203

Zone 27

including

464.7

465.2

0.5

13.2



694.1

696.4

2.3

6.32


UDD_4100

Underdog

OSK-W-21-2479-W11

709.7

712.0

2.3

9.08


UDD_4102

Underdog

including

709.7

710.0

0.3

22.5


and

710.3

710.7

0.4

33.3


OSK-W-21-2531-W3

635.0

637.6

2.6

5.99


CA2_2206

Caribou

including

636.7

637.6

0.9

13.9


OSK-W-21-2531-W4

870.6

872.6

2.0

4.42


UDD_4100

Underdog


1043.5

1045.7

2.2

3.56


UDD_4915

Underdog


1075.7

1077.7

2.0

3.50


UDD_4501

Underdog

including

1075.7

1076.0

0.3

16.1


OSK-W-21-2532-W3

909.0

911.0

2.0

7.17


UDD_4106

Underdog


1036.0

1038.0

2.0

4.23


UDD_4911

Underdog


1081.6

1086.0

4.4

22.3

20.6

UDD_4513

Underdog

including

1084.7

1085.4

0.7

111

100


1139.0

1141.0

2.0

6.04


UDD_4512

Underdog

OSK-W-21-2537-W3

908.0

910.6

2.6

127

61.2

TLX_3161

Triple Lynx

including

909.1

910.0

0.9

276

100

OSK-W-21-2551-W4

834.6

836.8

2.2

15.9


LX4_3424

Lynx 4

including

836.3

836.8

0.5

67.7



887.6

889.9

2.3

28.9


LX4_3414

Lynx 4

including

889.4

889.9

0.5

90.1



900.0

902.0

2.0

3.75


LX4_3437

Lynx 4


911.0

913.0

2.0

7.13


LX4_3437

Lynx 4

OSK-W-21-2578

156.0

158.0

2.0

14.6


CA1_2505

Caribou

including

157.0

158.0

1.0

28.8



165.9

168.0

2.1

9.77


CA1_2505

Caribou


178.0

180.0

2.0

6.42


CA1_2505

Caribou

OSK-W-21-2578-W2

606.0

608.0

2.0

3.60


UDD_4100

Underdog

OSK-W-21-2587

1042.5

1046.0

3.5

7.33


TLX_3164

Triple Lynx


1073.0

1077.0

4.0

21.3


TLX_3162

Triple Lynx

including

1075.8

1077.0

1.2

42.9



1098.4

1101.1

2.7

576

20.0

TLX_3170

Triple Lynx

including

1100.7

1101.1

0.4

3850

100


1104.1

1112.2

8.1

15.7


TLX_3170

Triple Lynx

including

1107.7

1108.1

0.4

63.1


OSK-W-21-2589-W2

736.2

738.5

2.3

34.9


TLX_3171

Triple Lynx

including

737.1

738.0

0.9

88.1


OSK-W-21-2600

650.3

652.5

2.2

6.14


UDD_4914

Underdog

including

650.3

650.6

0.3

14.2


OSK-W-21-2606

699.0

702.0

3.0

93.1

63.0

CA2_2208

Caribou

including

700.0

701.0

1.0

191

100

OSK-W-21-2609

638.0

640.0

2.0

6.33


CA2_2237

Caribou

including

638.9

639.5

0.6

16.0


OSK-W-21-2612

377.0

383.0

6.0

4.71


Z27_1102

Zone 27

OSK-W-21-2615

193.7

195.7

2.0

4.01


WFN_7009

Windfall North

OSK-W-21-2618

207.0

209.0

2.0

5.86


WFN_7009

Windfall North

OSK-W-21-2620

701.0

703.0

2.0

4.59


CAE_2547

Caribou

OSK-W-21-2622

191.4

193.4

2.0

7.29


WFN_7010

Windfall North

including

192.8

193.4

0.6

24.1


OSK-W-21-2627

57.0

59.0

2.0

20.6


WFN_7003

Windfall North

including

57.6

58.6

1.0

39.9


WST-21-0649

541.0

543.0

2.0

21.8

16.7

LX4_3450

Lynx 4

including

541.7

542.0

0.3

134

100

WST-21-0784

265.0

267.1

2.1

3.52


TLX_3161

Triple Lynx

including

266.3

266.8

0.5

14.0


WST-21-0855B

562.7

566.6

3.9

14.0


LX4_3440

Lynx 4

including

566.3

566.6

0.3

58.7


WST-21-0859

277.3

280.2

2.9

17.5


LSW_3508

Lynx SW

including

278.3

278.7

0.4

66.7



347.0

349.0

2.0

29.6

19.5

TLX_3166

Triple Lynx

including

347.9

348.2

0.3

167

100

WST-21-0868A

196.0

198.1

2.1

44.6


TLX_3161

Triple Lynx


302.0

305.0

3.0

6.14


TLX_3182

Triple Lynx


336.0

338.0

2.0

5.50


TLX_3131

Triple Lynx

WST-21-0877

79.6

81.6

2.0

4.51


LXM_3339

Lynx

including

80.9

81.6

0.7

12.6


WST-21-0879

669.5

671.5

2.0

19.6


LX4_3412

Lynx 4

including

669.5

670.5

1.0

39.1


WST-21-0899C

213.1

215.3

2.2

5.80


LSW_3507

Lynx SW


313.1

315.4

2.3

6.04


LSW_3556

Lynx SW

WST-21-0901

313.0

315.0

2.0

7.51


LHW_3215

Lynx HW

WST-21-0906A

357.5

359.7

2.2

4.42


LSW_3556

Lynx SW

WST-21-0910A

396.3

399.0

2.7

11.1


LSW_3556

Lynx SW

including

397.9

398.6

0.7

30.1



Notes: True widths are estimated at 55 – 80% of the reported core length interval. See "Quality Control and Reporting Protocols" below. CA1 and CA2 = Caribou, LX4 = Lynx 4, LHW = Lynx Hanging Wall, LXM = Lynx Main, LSW = Lynx Southwest, TLX = Triple Lynx, UDD = Underdog, WNF = Windfall North and Z27 = Zone 27.




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-21-1871-W1

844.0

846.0

2.0

5.55


UDD

Underdog

OSK-W-21-1949-W11

1028.1

1030.2

2.1

17.6


LX4

Lynx 4

including

1029.2

1029.6

0.4

72.0



1068.0

1071.4

3.4

3.66


LX4

Lynx 4


1101.7

1103.8

2.1

4.73


LX4

Lynx 4

including

1102.4

1102.7

0.3

22.9


OSK-W-21-2287-W9

943.6

945.6

2.0

4.57


LX4

Lynx 4

including

943.6

944.1

0.5

18.2


OSK-W-21-2416-W6

986.0

988.3

2.3

9.75


TLX

Triple Lynx

OSK-W-21-2479-W11

470.7

472.8

2.1

8.28


Z27

Zone 27

including

470.7

471.1

0.4

27.5



773.0

775.2

2.2

5.95


UDD

Underdog


879.7

882.0

2.3

6.37


UDD

Underdog

including

879.7

880.4

0.7

20.5


OSK-W-21-2522-W4

754.0

756.2

2.2

6.14


Lynx

Lynx

OSK-W-21-2532-W3

691.9

694.0

2.1

12.6


UDD

Underdog

including

691.9

692.8

0.9

28.7



1089.0

1091.0

2.0

15.0


UDD

Underdog

including

1089.4

1090.0

0.6

37.7


OSK-W-21-2540-W4

978.7

983.6

4.9

28.6


TLX

Triple Lynx

including

983.0

983.6

0.6

74.9


OSK-W-21-2540-W5

936.0

940.8

4.8

11.0


TLX

Triple Lynx

OSK-W-21-2540-W6

931.0

933.2

2.2

9.62


TLX

Triple Lynx

OSK-W-21-2548

235.5

238.5

3.0

3.70


BCT

Bobcat


252.3

254.5

2.2

3.64


BCT

Bobcat


358.0

360.1

2.1

4.19


BCT

Bobcat

OSK-W-21-2578

376.8

380.3

3.5

10.6


Z27

Zone 27


691.1

693.2

2.1

10.8


UDD

Underdog

including

692.6

692.9

0.3

67.0


OSK-W-21-2578-W2

590.0

592.0

2.0

7.84


UDD

Underdog

including

590.0

590.8

0.8

19.0



706.0

709.2

3.2

6.00


UDD

Underdog


917.9

920.1

2.2

4.10


UDD

Underdog

including

919.3

919.6

0.3

27.8


OSK-W-21-2587

978.4

989.0

10.6

17.6

17.6

TLX

Triple Lynx

including

982.3

983.0

0.7

101

100

and

983.0

983.7

0.7

77.2



1054.0

1056.0

2.0

5.53


TLX

Triple Lynx


1060.0

1062.0

2.0

9.86


TLX

Triple Lynx

including

1061.0

1062.0

1.0

18.3


OSK-W-21-2593

696.4

698.5

2.1

7.44


LX4

Lynx 4

including

696.4

697.0

0.6

17.9


OSK-W-21-2595

343.7

346.3

2.6

12.0


CAE

Caribou

including

345.9

346.3

0.4

52.1



456.0

458.0

2.0

5.39


CAE

Caribou

including

457.2

457.6

0.4

26.4



527.7

530.1

2.4

8.50


CAE

Caribou

including

528.1

528.7

0.6

24.9



559.0

561.0

2.0

5.68


CAE

Caribou

including

559.3

559.9

0.6

16.2



568.8

571.3

2.5

7.32


CAE

Caribou

including

570.9

571.3

0.4

17.5



646.5

648.5

2.0

9.53


CAE

Caribou

including

646.5

647.0

0.5

36.0



651.0

653.2

2.2

24.7


CAE

Caribou

including

652.7

653.2

0.5

98.5


OSK-W-21-2606

581.0

583.7

2.7

5.99


CAE

Caribou

including

583.1

583.7

0.6

26.8


OSK-W-21-2609

646.3

648.4

2.1

25.6


CA2

Caribou

including

646.8

647.4

0.6

84.3


OSK-W-21-2610

534.7

536.7

2.0

4.57


CAE

Caribou

OSK-W-21-2612

301.7

303.8

2.1

13.2


Z27

Zone 27


309.0

311.0

2.0

7.35


Z27

Zone 27

OSK-W-21-2616

208.3

210.3

2.0

4.01


WFN

Windfall North

OSK-W-21-2623

170.0

172.0

2.0

5.36


WFN

Windfall North


195.0

197.5

2.5

4.86


WFN

Windfall North

including

196.7

197.5

0.8

13.8


OSK-W-21-2624

18.0

20.0

2.0

10.8


WFN

Windfall North

WST-21-0771C

285.2

287.6

2.4

4.46


LSW

Lynx SW

WST-21-0855B

505.5

507.8

2.3

13.0


LX4

Lynx 4

including

505.5

506.2

0.7

30.8


WST-21-0857A

38.0

40.4

2.4

18.4


LXM

Lynx

including

39.4

40.0

0.6

66.3



363.2

370.0

6.8

15.4

14.8

TLX

Triple Lynx

including

363.9

364.6

0.7

106

100


463.2

465.3

2.1

4.46


TLX

Triple Lynx

including

464.4

465.3

0.9

8.32


WST-21-0860

245.9

248.1

2.2

5.87


TLX

Triple Lynx

including

246.5

247.0

0.5

24.4


WST-21-0863

388.0

390.0

2.0

8.66


TLX

Triple Lynx

WST-21-0868A

228.0

231.0

3.0

4.31


TLX

Triple Lynx


234.0

236.5

2.5

5.34


TLX

Triple Lynx


241.5

243.5

2.0

5.85


TLX

Triple Lynx


373.6

375.9

2.3

5.88


TLX

Triple Lynx


559.2

561.5

2.3

7.11


LX4

Lynx 4

WST-21-0877

307.7

309.7

2.0

221

15.1

LSW

Lynx SW

including

309.1

309.4

0.3

1475

100

WST-21-0885B

148.5

150.5

2.0

6.49


LSW

Lynx SW

including

149.5

150.5

1.0

13.0



296.5

300.5

4.0

12.8


LSW

Lynx SW

WST-21-0886

100.6

102.7

2.1

11.8


BCT

Bobcat

including

101.7

102.4

0.7

30.5


WST-21-0898

391.7

394.7

3.0

28.2


TLX

Triple Lynx

including

392.8

394.0

1.2

61.9


WST-21-0899B

164.9

167.0

2.1

6.35


LSW

Lynx SW


220.2

225.3

5.1

10.2


LSW

Lynx SW

including

220.2

221.0

0.8

25.8


WST-21-0899C

372.0

374.0

2.0

8.81


LSW

Lynx SW

including

373.2

373.6

0.4

43.7


WST-21-0910A

97.2

99.3

2.1

4.04


BCT

Bobcat

including

98.1

98.7

0.6

13.9



169.5

171.5

2.0

10.3


LSW

Lynx SW

including

171.0

171.5

0.5

39.0



290.0

292.0

2.0

21.2


LSW

Lynx SW

including

290.3

291.0

0.7

55.9



Notes: True widths are estimated at 55 – 80% of the reported core length interval. See "Quality Control and Reporting Protocols" below. BCT = Bobcat, CAE and CA2 = Caribou, LSW = Lynx Southwest, LXM = Lynx Main, LX4 = Lynx 4, TLX = Triple Lynx, UDD = Underdog, WFN = Windfall North and Z27 = Zone 27.

Drill hole location

Hole Number

Azimuth (°)

Dip
(°)

Length
(m)

UTM E

UTM N

Elevation

Section

OSK-W-21-1871-W1

331

-56

1119

452496

5434397

402

2475

OSK-W-21-1949-W11

105

-57

1314

453440

5435479

401

3825

OSK-W-21-1963-W7

123

-58

1431

453761

5435816

401

4275

OSK-W-21-1963-W8

123

-58

1452

453761

5435816

401

4275

OSK-W-21-2287-W7

116

-53

1320

453607

5435714

404

4075

OSK-W-21-2287-W9

116

-53

1329

453607

5435714

404

4075

OSK-W-21-2400-W1

336

-53

861

452878

5434419

401

2825

OSK-W-21-2416-W6

123

-54

990

453169

5435624

412

3650

OSK-W-21-2416-W7

123

-54

1104

453169

5435624

412

3650

OSK-W-21-2479-W10

344

-55

807

452315

5434420

399

2325

OSK-W-21-2479-W11

344

-55

1005

452315

5434420

399

2325

OSK-W-21-2522-W4

128

-54

1208

453450

5435592

411

3900

OSK-W-21-2531-W3

344

-62

1329

452566

5434415

403

2550

OSK-W-21-2531-W4

344

-62

1203

452566

5434415

403

2550

OSK-W-21-2532-W3

341

-60

1191

452478

5434430

401

2475

OSK-W-21-2537-W3

114

-54

1024

452981

5435549

420

3450

OSK-W-21-2540-W4

117

-60

1297

453465

5435640

410

3925

OSK-W-21-2540-W5

117

-60

1311

453465

5435640

410

3925

OSK-W-21-2540-W6

117

-60

1541

453465

5435640

410

3925

OSK-W-21-2548

331

-57

774

452832

5434545

398

2850

OSK-W-21-2551-W4

120

-55

1026

453622

5435635

405

4050

OSK-W-21-2578

350

-53

942

452178

5434397

399

2200

OSK-W-21-2578-W2

350

-53

924

452178

5434397

399

2200

OSK-W-21-2587

127

-59

1278

453350

5435673

418

3850

OSK-W-21-2589-W2

130

-49

969

452960

5435539

420

3425

OSK-W-21-2593

18

-76

833

454135

5435058

397

4225

OSK-W-21-2595

150

-60

742

452830

5435324

414

3225

OSK-W-21-2600

329

-50

789

452470

5434626

403

2550

OSK-W-21-2606

325

-61

774

452786

5434526

398

2800

OSK-W-21-2609

338

-62

711

452683

5434351

402

2625

OSK-W-21-2610

153

-62

684

452831

5435324

414

3225

OSK-W-21-2612

333

-51

717

452391

5434638

402

2500

OSK-W-21-2615

338

-60

258

452248

5435150

412

2625

OSK-W-21-2616

341

-56

264

452279

5435163

411

2650

OSK-W-21-2618

330

-56

248

452279

5435162

411

2650

OSK-W-21-2620

145

-59

723

452769

5435312

406

3150

OSK-W-21-2622

328

-63

249

452247

5435150

412

2625

OSK-W-21-2623

336

-50

279

452278

5435162

411

2650

OSK-W-21-2624

351

-47

93

452186

5435122

405

2550

OSK-W-21-2627

155

-45

105

452196

5435179

405

2600

WST-21-0649

136

-47

790

453258

5435211

98

3525

WST-21-0771C

127

-52

357

452954

5435003

252

3175

WST-21-0784

132

-66

361

453507

5435327

-7

3800

WST-21-0855B

118

-45

751

453507

5435333

-48

3800

WST-21-0857A

141

-51

592

453322

5435236

54

3600

WST-21-0859

133

-66

499

453105

5435067

231

3325

WST-21-0860

126

-60

304

453508

5435328

-7

3800

WST-21-0863

135

-64

403

453508

5435327

-7

3800

WST-21-0868A

130

-44

922

453374

5435296

-26

3675

WST-21-0877

158

-60

490

453105

5435065

231

3325

WST-21-0879

139

-44

724

453258

5435209

96

3525

WST-21-0885B

145

-53

377

452954

5435003

253

3175

WST-21-0886

128

-51

375

452954

5435004

253

3175

WST-21-0898

141

-61

402

453508

5435327

-7

3800

WST-21-0899B

134

-60

287

452955

5435004

253

3175

WST-21-0899C

139

-58

434

452955

5435004

252

3175

WST-21-0901

116

-18

340

453462

5435327

32

3775

WST-21-0906A

133

-58

381

453105

5435066

231

3325

WST-21-0910A

143

-63

438

452954

5435004

252

3175


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.

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.

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.

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.

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.

Windfall North
Mineralization is hosted in sheared andesites and most commonly occurs in gold-bearing quartz veins with trace to 10% pyrite, traces of sphalerite and chalcopyrite, and local visible gold. Mineralization is hosted in a silica-carbonate-sericite alteration envelope and is constrained within shear zones with pervasive sericite-carbonate ± fuchsite ± silica alteration.

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 February 17, 2021 is supported by the technical report entitled “Preliminary Economic Assessment Update for the Windfall Project” dated April 26, 2021 (that includes Windfall Mineral Resource Estimate 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