77.6 g/t Au Over 17.3 Metres; and 45.8 g/t Au Over 11.0 Metres in Lynx 4

124 g/t Au Over 8.0 Metres in Triple Lynx

(Toronto, January 18, 2022) 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 that have not been included in the recently released mineral resource estimate (“MRE”) (see Osisko news release dated January 10, 2022) are presented below, and include 94 intercepts in 28 drill holes (9 from surface, 19 from underground) and 25 wedges. The infill intercepts are located inside defined January 2022 MRE blocks.  The expansion intercepts are located outside the January 2022 MRE blocks and either expand MRE wireframes or are in a defined zone or corridor but do not yet correlate to a specific MRE wireframe.

Osisko Chief Executive Officer John Burzynski commented: “Today’s results serve as a reminder that Windfall continues to grow in size, underscored by some of these new wide high-grade hits as the deposit opens up in the heart of the Lynx system.  By virtue of the current resource, Windfall is the largest high-grade million ounce plus deposit ever discovered in Québec, and it has been steadily moving up the global list of top high-grade underground gold deposits.  There is nothing quite like Windfall in Canada, or even globally.”

Selected high-grade intercepts include: 482 g/t Au over 5.7 metres and 380 g/t Au over 3.2 metres in OSK-W-21-1432-W10; 77.6 g/t Au over 17.3 metres in OSK-W-21-1949-W14; 124 g/t Au over 8.0 metres in OSK-W-21-2587-W2; 45.8 g/t Au over 11.0 metres and 143 g/t Au over 3.4 metres in WST-21-0707; 87.9 g/t Au over 3.2 metres in OSK-W-21-2465-W5; 83.0 g/t Au over 3.0 metres in WST-21-0895A, 37.0 g/t Au over 6.4 metres in OSK-W-21-2613 and 28.1 g/t Au over 6.0 metres in OSK-W-21-2644. Maps showing hole locations and full analytical results are available at www.osiskomining.com. Maps: Long Section_All zones Infill EN 20220118, Long Section_All zones Expan EN 20220118, PR_EN_20220118_Surface, PR_EN_20220118_UG

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-21-1432-W10	957.3	960.5	3.2	380	44.9	LX4_3460	Lynx 4
including	958.0	958.4	0.4	1240	100
and	959.7	960.1	0.4	1640	100
OSK-W-21-1432-W11	955.3	957.3	2.0	10.8		LX4_3433	Lynx 4
including	956.4	956.8	0.4	45.0
OSK-W-21-1432-W12	988.3	991.4	3.1	16.7		LX4_3460	Lynx 4
including	991.0	991.4	0.4	95.9
OSK-W-21-1871-W1	949.0	951.0	2.0	5.81		UDD_4501	Underdog
including	949.6	950.0	0.4	27.7
OSK-W-21-1871-W2	507.0	509.0	2.0	4.50		CA2_2225	Caribou
including	508.0	508.7	0.7	12.4
OSK-W-21-1949-W12	1047.9	1050.0	2.1	3.57		LX4_3430	Lynx 4
OSK-W-21-1949-W14	749.0	751.0	2.0	47.8	30.1	LXM_3345	Lynx
including	749.0	749.5	0.5	171	100
	1163.0	1180.3	17.3	77.6	27.2	LX4_3463	Lynx 4
including	1169.8	1170.2	0.4	704	100
and	1172.8	1173.2	0.4	481	100
and	1173.6	1174.0	0.4	1195	100
OSK-W-21-2479-W11	976.5	978.5	2.0	14.3		UDD_4910	Underdog
including	976.9	977.5	0.6	44.6
OSK-W-21-2531-W4	590.3	592.4	2.1	9.37		CA2_2266	Caribou
	595.0	597.0	2.0	7.06		CA2_2266	Caribou
	618.7	620.7	2.0	3.86		CA2_2257	Caribou
including	619.7	620.3	0.6	9.46
	777.2	781.0	3.8	13.8		UDD_4112	Underdog
including	777.2	777.7	0.5	81.5
OSK-W-21-2544-W1	781.4	783.4	2.0	3.68		TLX_3171	Triple Lynx
	976.1	981.0	4.9	8.30		TLX_3195	Triple Lynx
including	976.1	976.4	0.3	50.0
OSK-W-21-2544-W2	802.0	804.3	2.3	20.0		TLX_3159	Triple Lynx
including	802.0	802.6	0.6	59.4
	909.8	911.8	2.0	10.7		TLX_3193	Triple Lynx
including	910.4	910.8	0.4	52.1
	921.6	923.7	2.1	10.3		TLX_3194	Triple Lynx
including	922.4	922.7	0.3	71.6
OSK-W-21-2544-W4	770.3	773.0	2.7	14.6		TLX_3171	Triple Lynx
including	771.0	771.7	0.7	44.0
	776.0	780.0	4.0	8.74		TLX_3171	Triple Lynx
OSK-W-21-2587-W1	1119.0	1126.0	7.0	21.0		TLX_3172	Triple Lynx
including	1123.5	1124.0	0.5	99.1
and	1125.7	1126.0	0.3	67.8
OSK-W-21-2587-W2	1134.0	1142.0	8.0	124	36.9	TLX_3172	Triple Lynx
including	1136.7	1137.0	0.3	1685	100
and	1139.7	1140.4	0.7	371	100
OSK-W-21-2612-W1	396.0	398.0	2.0	4.50		Z27_1115	Zone 27
OSK-W-21-2613	911.0	913.0	2.0	6.35		TLX_3161	Triple Lynx
	944.1	950.5	6.4	37.0	33.1	TLX_3161	Triple Lynx
including	947.3	947.6	0.3	114	100
and	947.9	948.4	0.5	142	100
OSK-W-21-2618	60.0	62.2	2.2	13.9		WFN_7003	Windfall North
including	60.0	61.0	1.0	30.2
OSK-W-21-2621-W1	629.3	633.0	3.7	13.7		UDD_4100	Underdog
including	629.3	629.7	0.4	31.9		UDD_4100	Underdog
and	632.0	633.0	1.0	31.5
OSK-W-21-2626	103.4	106.0	2.6	13.7		F11_6001	F-11
OSK-W-21-2635	555.8	558.0	2.2	3.98		CA2_2232	Caribou
OSK-W-21-2637	548.0	550.0	2.0	13.9		CAE_2559	Caribou
including	548.8	549.4	0.6	44.0
OSK-W-21-2641	131.8	133.8	2.0	25.6		F11_6009	F-11
including	132.6	133.2	0.6	64.0
OSK-W-21-2645	126.1	128.1	2.0	19.0		F11_6000	F-11
including	126.1	126.9	0.8	45.1
	133.0	135.0	2.0	10.1		F11_6000	F-11
WST-21-0649	710.4	714.4	4.0	27.3	26.5	LX4_3427	Lynx 4
including	710.4	710.8	0.4	109	100
WST-21-0707	180.0	183.4	3.4	143	67.8	LXM_3388	Lynx
including	182.2	183.4	1.2	255	100
	499.5	510.5	11.0	45.8	38.4	LX4_3430	Lynx 4
including	499.5	500.0	0.5	99.2
and	507.0	507.8	0.8	202	100
	532.1	537.4	5.3	8.43		LX4_3434	Lynx 4
including	535.7	536.1	0.4	17.7
and	536.7	537.4	0.7	29.1
WST-21-0861	87.0	89.5	2.5	24.3	24.2	LXM_3339	Lynx
including	88.9	89.5	0.6	101	100
WST-21-0864A	257.5	259.5	2.0	4.94		LHW_3203	Lynx HW
including	258.2	258.8	0.6	15.0
WST-21-0878	503.9	506.2	2.3	4.30		LX4_3401	Lynx 4
including	505.5	505.8	0.3	27.6
	614.0	616.4	2.4	25.1		LX4_3448	Lynx 4
including	614.0	614.6	0.6	99.1
WST-21-0883	341.4	343.5	2.1	5.88		TLX_3166	Triple Lynx
including	342.2	342.5	0.3	27.7
WST-21-0895A	480.3	482.8	2.5	26.6		LX4_3404	Lynx 4
including	481.4	481.8	0.4	75.1
	519.3	522.3	3.0	83.0	44.0	LX4_3440	Lynx 4
including	520.0	520.7	0.7	254	100
WST-21-0900	291.6	294.4	2.8	18.9		LHW_3216	Lynx HW
including	294.0	294.4	0.4	84.8
WST-21-0905C	52.3	54.5	2.2	13.7		LXM_3339	Lynx
including	52.9	53.4	0.5	52.2
	65.6	69.0	3.4	12.7		LXM_3311	Lynx
including	66.5	67.0	0.5	34.8
	211.0	213.0	2.0	11.2		LSW_3504	Lynx SW
WST-21-0907	543.2	545.4	2.2	5.02		LX4_3401	Lynx 4
WST-21-0908B	195.0	197.0	2.0	15.6		TLX_3121	Triple Lynx
including	195.3	195.7	0.4	62.9
WST-21-0911	175.7	177.9	2.2	10.5		LXM_3388	Lynx
including	177.3	177.9	0.6	21.3
	526.9	529.0	2.1	4.41		LX4_3404	Lynx 4
including	527.3	527.6	0.3	25.4
	530.0	532.0	2.0	3.68		LX4_3404	Lynx 4
WST-21-0913	526.0	528.0	2.0	11.0		LX4_3450	Lynx 4
including	527.1	527.4	0.3	68.5
WST-21-0916A	526.8	529.0	2.2	11.9		LX4_3450	Lynx 4
including	526.8	527.2	0.4	57.4
WST-21-0918	345.0	347.0	2.0	26.4	25.9	TLX_3131	Triple Lynx
including	346.0	346.5	0.5	102	100
	516.7	518.7	2.0	30.7		LX4_3401	Lynx 4
including	517.8	518.3	0.5	72.5
WST-21-0932	155.0	157.0	2.0	10.9		LXM_3388	Lynx
including	155.8	156.1	0.3	47.1
	182.0	184.0	2.0	3.89		LHW_3206	Lynx HW

Notes: True widths are estimated at 55 – 80% of the reported core length interval. See “Quality Control and Reporting Protocols” below. CAE and CA2 = Caribou, LX4 = Lynx 4, LHW = Lynx Hanging Wall, LXM = Lynx Main, LSW = Lynx Southwest, TLX = Triple Lynx, UDD = Underdog, WNF = Windfall North, F11 = F11 Zone, 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-21-1432-W10	851.5	853.5	2.0	4.70		LX4	Lynx 4
	915.7	921.4	5.7	482	27.5	LX4	Lynx 4
including	915.7	916.2	0.5	975	100
and	917.6	917.9	0.3	2540	100
and	920.8	921.1	0.3	4330	100
OSK-W-21-1871-W1	941.6	946.7	5.1	8.53		UDD	Underdog
including	941.6	942.1	0.5	23.2
and	944.8	945.1	0.3	40.9
OSK-W-21-1871-W3	722.3	724.4	2.1	11.2		UDD	Underdog
including	723.7	724.4	0.7	23.2
OSK-W-21-1949-W12	1018.8	1021.0	2.2	19.0		LX4	Lynx 4
	1144.2	1146.5	2.3	10.2		LX4	Lynx 4
including	1144.2	1145.0	0.8	29.2
OSK-W-21-1949-W14	1060.7	1062.7	2.0	6.93		LX4	Lynx 4
including	1061.5	1062.0	0.5	23.2
	1068.7	1070.7	2.0	5.92		LX4	Lynx 4
	1137.8	1140.4	2.6	4.01		LX4	Lynx 4
including	1139.0	1139.3	0.3	9.74
	1185.2	1188.9	3.7	8.84		LX4	Lynx 4
including	1185.2	1185.5	0.3	27.9
and	1188.0	1188.9	0.9	20.4
	1203.5	1214.0	10.5	6.26		LX4	Lynx 4
including	1213.6	1214.0	0.4	26.4
	1217.0	1219.0	2.0	4.14		LX4	Lynx 4
	1228.8	1230.9	2.1	4.81		LX4	Lynx 4
OSK-W-21-2287-W10	1121.5	1124.0	2.5	13.1		LX4	Lynx 4
including	1121.5	1122.5	1.0	32.6
OSK-W-21-2369-W3	962.0	964.0	2.0	32.4	30.5	LX4	Lynx 4
including	962.0	962.6	0.6	106	100
OSK-W-21-2381-W2	1267.2	1269.4	2.2	3.82		LX4	Lynx 4
including	1268.7	1269.4	0.7	10.3
OSK-W-21-2465-W5	824.3	827.5	3.2	87.9	71.8	TLX	Triple Lynx
including	824.3	825.0	0.7	146	100
including	825.5	825.9	0.4	131	100
including	825.9	826.9	1.0	108	100
OSK-W-21-2465-W6	765.5	767.7	2.2	15.1		TLX	Triple Lynx
including	765.5	766.0	0.5	60.0
OSK-W-21-2540-W4	1106.9	1109.0	2.1	48.4	14.7	TLX	Triple Lynx
including	1106.9	1107.2	0.3	336	100
OSK-W-21-2601-W1	1042.0	1044.0	2.0	4.04		TLX	Triple Lynx
OSK-W-21-2621-W1	668.0	670.0	2.0	4.02		UDD	Underdog
OSK-W-21-2629	903.3	907.2	3.9	20.1		LX4	Lynx 4
including	903.3	904.3	1.0	64.2
OSK-W-21-2637	561.3	564.0	2.7	28.0		Caribou	Caribou
OSK-W-21-2640-W1	635.6	637.6	2.0	3.86		Caribou	Caribou
OSK-W-21-2644	504.0	506.0	2.0	6.53		Caribou	Caribou
	509.0	511.0	2.0	4.21		Caribou	Caribou
including	509.0	509.7	0.7	10.3
	656.0	658.1	2.1	5.69		Caribou	Caribou
	662.0	668.0	6.0	28.1		Caribou	Caribou
including	664.0	665.0	1.0	92.6
WST-21-0784	335.8	337.8	2.0	6.02		TLX	Triple Lynx
WST-21-0885B	326.3	331.0	4.7	24.9	19.1	LSW	Lynx SW
including	327.0	327.5	0.5	155	100
and	330.6	331.0	0.4	55.3
WST-21-0907	186.0	188.0	2.0	18.3		TLX	Triple Lynx
including	186.4	186.8	0.4	91.2
	549.0	551.0	2.0	13.6		LX4	Lynx 4
including	549.6	550.0	0.4	66.1
WST-21-0909	231.1	233.3	2.2	57.5	51.2	TLX	Triple Lynx
including	232.1	232.5	0.4	135	100
WST-21-0911	564.2	568.8	4.6	7.90		LX4	Lynx 4
WST-21-0918	646.0	648.0	2.0	11.6		LX4	Lynx 4

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

Drill hole location

Hole Number	Azimuth (°)	Dip (°)	Length (m)	UTM E	UTM N	Elevation	Section
OSK-W-21-1432-W10	132	-55	1062	453811	5435779	400	4300
OSK-W-21-1432-W11	132	-55	1149	453811	5435779	400	4300
OSK-W-21-1432-W12	132	-55	1113	453811	5435779	400	4300
OSK-W-21-1871-W1	331	-56	1119	452496	5434397	402	2475
OSK-W-21-1871-W2	331	-56	915	452496	5434397	402	2475
OSK-W-21-1871-W3	331	-56	906	452496	5434397	402	2475
OSK-W-21-1949-W12	105	-57	1301	453440	5435479	401	3825
OSK-W-21-1949-W14	105	-57	1332	453440	5435479	401	3825
OSK-W-21-2287-W10	116	-53	1311	453607	5435714	404	4075
OSK-W-21-2369-W3	130	-56	1415	453424	5435566	410	3850
OSK-W-21-2381-W2	134	-53	887	453620	5435790	402	4125
OSK-W-21-2465-W5	123	-61	1062	453398	5435556	413	3825
OSK-W-21-2465-W6	123	-61	993	453398	5435556	413	3825
OSK-W-21-2479-W11	344	-55	1005	452315	5434420	399	2325
OSK-W-21-2531-W4	344	-62	1203	452566	5434415	403	2550
OSK-W-21-2540-W4	117	-60	1297	453465	5435640	410	3925
OSK-W-21-2544-W1	128	-50	1140	452960	5435539	419	3425
OSK-W-21-2544-W2	128	-50	1044	452960	5435539	419	3425
OSK-W-21-2544-W4	128	-50	858	452960	5435539	419	3425
OSK-W-21-2587-W1	127	-59	1176	453350	5435673	418	3850
OSK-W-21-2587-W2	127	-59	1167	453350	5435673	418	3850
OSK-W-21-2601-W1	125	-61	1235	453425	5435657	413	3900
OSK-W-21-2612-W1	333	-51	690	452391	5434638	402	2500
OSK-W-21-2613	114	-53	1092	452981	5435549	420	3450
OSK-W-21-2618	330	-56	248	452279	5435162	411	2650
OSK-W-21-2621-W1	344	-53	765	452272	5434396	399	2275
OSK-W-21-2626	153	-47	156	452299	5435823	406	3000
OSK-W-21-2629	114	-57	1011	453622	5435635	405	4050
OSK-W-21-2635	327	-56	708	452684	5434475	402	2675
OSK-W-21-2637	140	-59	747	452768	5435312	406	3150
OSK-W-21-2640-W1	336	-58	737	452683	5434351	402	2625
OSK-W-21-2641	177	-46	165	452436	5435884	407	3150
OSK-W-21-2644	346	-55	693	452566	5434415	403	2550
OSK-W-21-2645	157	-48	189	452409	5435902	406	3125
WST-21-0649	136	-47	790	453258	5435211	98	3525
WST-21-0707	118	-41	633	453507	5435332	-48	3800
WST-21-0784	132	-66	361	453507	5435327	-7	3800
WST-21-0861	139	-64	307	453106	5435066	231	3325
WST-21-0864A	121	-1	292	453463	5435327	33	3775
WST-21-0878	128	-40	711	453375	5435297	-26	3675
WST-21-0883	126	-59	393	453105	5435065	231	3325
WST-21-0885B	145	-53	377	452954	5435003	253	3175
WST-21-0895A	123	-42	635	453507	5435332	-48	3800
WST-21-0900	122	-13	316	453462	5435326	33	3775
WST-21-0905C	141	-52	511	453221	5435121	134	3450
WST-21-0907	130	-40	701	453374	5435296	-26	3675
WST-21-0908B	118	-43	198	453506	5435326	-90	3800
WST-21-0909	151	-59	426	453507	5435328	-7	3800
WST-21-0911	121	-44	635	453507	5435332	-48	3800
WST-21-0913	138	-49	594	453322	5435236	54	3600
WST-21-0916A	146	-52	586	453321	5435235	54	3600
WST-21-0918	130	-40	663	453374	5435296	-26	3675
WST-21-0932	136	-26	360	453462	5435326	32	3775

 

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.

 

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.

 

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-Zones

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.

 

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 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, will be further described in the full technical report being prepared for this updated mineral resource estimate in accordance with NI 43-101, and will be available on SEDAR (www.sedar.com) under the Corporation’s issuer profile within 45 days from January 10, 2022. 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 2,600 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

3.2 Million Ounces Measured and Indicated Resource Averaging 10.5 g/t Au

3.6 Million Ounces Inferred Resource Averaging 8.6 g/t Au

 

(Toronto, January 10, 2022) Osisko Mining Inc. (OSK:TSX, “Osisko” or the “Corporation”) is pleased to provide the updated mineral resource estimate (“MRE”) for its 100% owned world-class Windfall gold deposit, located in the Abitibi greenstone belt, Urban Township, Eeyou Istchee James Bay, Québec.

 

This MRE reflects the results of approximately 1.7 million metres of drilling, with 1.5 million metres completed by Osisko since October 2015, and includes all drilling completed as of September 2021 and all analytical results received as of October 20, 2021.

 

An additional 70,000 metres of infill and expansion drilling has been completed since September 2021. This additional drilling and outstanding analytical results, together with ongoing surface and underground drilling, will be integrated into the database for the pending feasibility study expected to be completed in Q4 2022. Map of MRE & Upside potential.

 

HIGHLIGHTS

• 3.2 M oz measured & indicated (“M&I”) resource avg. 10.5 g/t Au
• M&I resource increase of 73% with avg. grade increased by 9%
• Lynx contains 60% of MRE total gold
• Lynx resource: M&I 2.3 M oz avg. 12g/t Au; Inferred 1.8 M oz avg. 10.9 g/t Au
• 3.6 M oz inferred resource avg. 8.6 g/t Au, reflecting a grade increase of 8%
• 50% of the MRE is hosted in 30 wireframes
• 98% of MRE is located from surface to 1200 m vertical depth
• Exploration ramp access currently at >600 m vertical depth in Lynx
• Lynx 600 bulk sample (Triple Lynx at level 600) work in progress; prior Lynx 311 bulk sample returned 189% positive grade reconciliation (see Osisko news release dated December 11, 2019)
• Strong open potential for expansion of high-grade zones in Lynx to the East and down plunge

 

Chief Executive Officer of Osisko John Burzynski commented: “The world-class Windfall deposit continues to impress with grade and scale. Infill drilling has again exceeded our expectations, with excellent conversion, and the M&I resource increasing by 73% with average gold grade moving past double digits to 10.5 g/t. This MRE forms a strong foundation for the upcoming feasibility study. We are confident that as we complete the remaining infill work in the coming months, the resource will continue to grow and we should again see incremental increase in what is already a strong average grade.”

 

Mr. Burzynski continued: “Windfall is an outstanding, well-defined deposit which still has demonstrable strong upside potential to grow. The consistent trend over the past five years of drilling, as we completed our extensive and detailed surface and underground work programs, has been steady growth of ounces and increasing high-grade. We are confident that Windfall will grow significantly in the future with continued work. We would like very much to thank our employees and contractors for their tremendous efforts to advance our project, our Cree First Nation hosts and partners, the local and provincial governments, and our stakeholders and shareholders for their strong support.”

 

The MRE sensitivity table (Table 1) shows the potential for additional resources through optimizing costs and cut-off grade which will be reviewed during feasibility work. Table 2 shows resources by main area of the Windfall deposit.

 

Table 1: Windfall Gold Deposit Mineral Resource Estimate Sensitivity Table⁽¹⁾

Cut-off (g/t Gold)	Measured + Indicated					Inferred
	Tonnes (000 t)	Gold (g/t)	Ag (g/t)	Gold  (000 oz)	Ag (000 oz)	Tonnes (000 t)	Gold (g/t)	Ag (g/t)	Gold  (000 oz)	Ag (000 oz)
5.0	6,904	12.9	6.0	2,859	1,336	8,568	10.8	6.0	2,986	1,648
4.5	7,635	12.1	5.7	2,971	1,406	9,709	10.1	5.6	3,160	1,734
4.0	8,472	11.3	5.4	3,084	1,483	11,241	9.3	5.1	3,369	1,849
3.5	9,472	10.5	5.2	3,204	1,570	13,035	8.6	4.7	3,585	1,984
3.0	10,680	9.7	4.8	3,330	1,662	15,282	7.8	4.3	3,819	2,132
2.5	12,127	8.9	4.5	3,456	1,766	18,554	6.9	3.9	4,108	2,327

Note: ⁽¹⁾ MRE cut-off of 3.5 g/t Au.

 

Table 2: Windfall Gold Deposit Mineral Resource Estimate by Area (3.5 g/t Au cut-off)

Area	Measured					Indicated						Inferred
	Tonnes(1) (000 t)	Gold (g/t)	Ag (g/t)	Gold(1) (000 oz)	Ag(1) (000 oz)	Tonnes(1) (000 t)	Gold (g/t)	Ag (g/t)	Gold(1) (000 oz)	Ag(1) (000 oz)	Tonnes(1) (000 t)		Gold (g/t)	Ag (g/t)	Gold(1) (000 oz)	Ag(1) (000 oz)
Lynx(2)	565	11.6	7.2	210	131	5,430	12.0	5.4	2,096	944	5,052		10.9	7.1	1,777	1,147
Underdog	–	–	–	–	–	800	9.5	3.3	244	85	4,419		7.9	3.0	1,119	432
Main(3)	–	–	–	–	–	2,676	7.6	4.8	654	410	2,909		5.8	3.3	540	306
Triple 8	–	–	–	–	–	–	–	–	–	–	655		7.1	4.7	149	99
Total	565	11.6	7.2	210	131	8,907	10.5	5.0	2,994	1,439	13,035		8.6	4.7	3,585	1,984

Notes: ⁽¹⁾ Values are rounded to nearest thousand which may cause apparent discrepancies. ⁽²⁾ Lynx area includes: Lynx Main, Lynx HW, Lynx SW, Lynx 4 and Triple Lynx. ⁽³⁾ Main area includes: Zone 27, Caribou 1&2, Caribou Extension, Bobcat, Mallard, Windfall Nord, and F-Zones. See Windfall Gold Deposit Mineral Resource Estimate notes further below.

 

This MRE reflects the results of 4,536 drill holes (1,722,097 metres of core) in the resource area, including 3,882 drill holes (1,539,984 metres of core) completed by Osisko from October 2015 to September 20, 2021 with assays up to October 20, 2021. The MRE (with an effective date of October 20, 2021) was prepared by Osisko, under the supervision of BBA Inc. The full technical report, which is being prepared in accordance with National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI-43-101”), will be available on SEDAR (www.sedar.com) under the Corporation’s issuer profile within 45 days.

 

This mineral resource estimate reflects the current status of the geological interpretation supported by infill drilling, underground mapping and bulk sample results. Most mineralized envelopes in the Main area are associated with pyritic stringers. Lynx and Underdog mineralized lenses predominantly form an extensive anastomosed network of quartz-rich and pyrite-rich veins. The mineralization system is located near contacts between volcanic and pre-mineral intrusive rocks in Main and Lynx areas, and more specifically, within pre-mineral intrusive units in Underdog.

 

The MRE is 50% contained within 30 wireframes, and 75% contained within 98 wireframes. The MRE considers a total of 556 mineralized lenses defined by individual wireframes with a minimum true thickness of 2.0 metres. The MRE reports grade blocks inside volumes potentially mineable by underground methods at a cut-off grade of 3.5 g/t Au. The cut-off calculation below has been rounded up to 3.5 g/t Au to better represent a future mining cut-off (Table 3).

 

Table 3: Parameters used to estimate the underground cut-off grade

for the Windfall Gold Deposit Mineral Resource Estimation

Parameters	Unit	Value
Gold Price	USD/oz	1,600
Exchange Rate	USD/CAD	1.26
Mill Recovery	%	94.9
Payability	%	99.95
Sell Cost	USD/oz	5
Royalties (NSR)	%	2
Mining Cost	CAD/t milled	107
G&A Cost	CAD/t milled	32
Processing Cost	CAD/t milled	31
Transportation	CAD/t milled	2
Environment	CAD/t milled	12
Calculated Cut-off Grade	g/t Au	3.1
MRE Cut-off Grade	g/t Au	3.5

 

Windfall Gold Deposit Mineral Resource Estimate Notes

1. The independent qualified person for the MRE, as defined by NI 43-101 guidelines, is Pierre-Luc Richard, P.Geo.(OGQ#1119), of BBA Inc. The effective date of the estimate is October 20, 2021.

 

2. The Windfall mineral resource estimate follows the November 29, 2019 CIM Estimation of Mineral Resources and Mineral Reserves Best Practice Guidelines.
3. These mineral resources are not mineral reserves as they have not demonstrated economic viability. The quantity and grade of reported Inferred mineral resources in this news release are uncertain in nature and there has been insufficient exploration to define these resources as indicated or measured; however, it is reasonably expected that the majority of inferred mineral resources could be upgraded to indicated mineral resources with continued exploration.
4. Resources are presented undiluted and in situ and are considered to have reasonable prospects for economic extraction. Isolated and discontinuous blocks above the stated cut-off grade are excluded from the mineral resource estimate. Must-take material, i.e. isolated blocks below cut-off grade located within a potentially mineable volume, was included in the mineral resource estimate.
5. As of October 20, 2021, the database comprises a total of 4,536 drill holes for 1,722,097 metres of drilling in the areal extent of the mineral resource estimate, of which 3,882 drill holes (1,539,984 metres) were completed and assayed by Osisko. The drill hole grid spacing is approximately 12.5 metre x 12.5 metre for definition drilling, 25 metre x 25 metre for infill drilling and larger for extension drilling.
6. All core assays reported by Osisko were obtained by analytical methods described below under “Quality Control and Reporting Protocols”.
7. Geological interpretation of the deposit is based on lithologies, mineralization style, alteration and structural features. Most mineralization envelopes are subvertical, striking NE-SW and plunging approximately 40 degrees towards the North-East. The 3D wireframing was generated in Leapfrog Geo, a modelling software, from hand selections of mineralization intervals. The mineral resource estimate includes a total of 556 tabular, mostly sub-vertical domains defined by individual wireframes with a minimum true thickness of 2.0 metres.
8. Assays were composited within the mineralization domains into 2.0 metres length composites. A value of 0.00125 g/t Au and 0.0025 g/t Ag (¼ of the detection limit) was applied to unassayed core intervals.
9. High-grade composites were capped. Cappings were determined in each area from statistical studies on groups of lenses sharing similar mineralization characteristics. Cappings vary from 6 g/t Au to 200 g/t Au and from 5 g/t Ag to 150 g/t Ag. A multiple capping strategy defined by capping values decreasing as interpolation search distances increase was used in the grade estimations.
10. Block models were produced using Datamine™ Studio RM Software. The models are defined by parent cell sizes of 5 metres NE, 2 meters NW and 5 metres height, and sublocked to minimum subcell sizes of 1.25 meters NE, 0.5 metres NW and 1.25 metres height.
11. Ordinary Kriging (OK) based interpolations were produced for gold estimations in each area of the Windfall deposit, while silver grade estimations for most projects were produced using Inverse Distance Squared (ID²) interpolations. Gold estimation parameters are based on composite variography analyses. The gold estimation parameters were used for the silver estimation.
12. Density values vary between 2.73 and 2.93 and are mainly based on the densities of lithologies within the mineralized lenses.
13. The Windfall mineral resource estimate is categorized as measured, indicated and inferred mineral resource as follows:
    1. The measured mineral resource category is manually defined and encloses areas where:
       12. drill spacing is less than 12.5 metres,
       13. blocks are informed by a minimum of four drill holes,

• geological evidence is sufficient to confirm geological and grade continuity.

1. lenses in the area have been accessed by underground workings.

1. The indicated mineral resource category is manually defined and encloses areas where:
   1. drill spacing is generally less than 25 metres,
   2. blocks are informed by a minimum of two drill holes,

• geological evidence is sufficient to assume geological and grade continuity.

1. The inferred mineral resource category is manually defined and encloses areas where:
   1. drill spacing is less than 100 metres,
   2. blocks are informed by a minimum of two drill holes,

• geological evidence is sufficient to imply, but not verify geological and grade continuity.

14. The mineral resource is reported at 3.5 g/t Au cut-off. The cut-off grade is based on the following economic parameters: gold price at 1,600 USD/oz, exchange rate at 1.26 USD/CAD, 94.9% mill recovery; payability of 99.95%; selling cost at 5 USD/oz, 2% NSR royalties, mining cost at 107 CAD/t milled, G&A cost at 32 CAD/t milled, processing cost at 31 CAD/t, transportation cost at 2 CAD/t considering mill at site, and environment cost at 12 CAD/t. A cut-off grade of 3.5 g/t Au was selected over the calculated cut-off grade of 3.1 g/t Au to better reflect a realistic mining cut-off.
15. Estimates use metric units (metres, tonnes and g/t). Metal contents are presented in troy ounces (metric tonne x grade / 31.103475).
16. The independent qualified person is not aware of any known environmental, permitting, legal, title-related, taxation, socio-political or marketing issues, or any other relevant issue, that could materially affect the mineral resource estimate.

 

17. Values in tonnes and ounces are rounded to nearest thousand which may cause apparent discrepancies.

 

Qualified Person

The Windfall mineral resource estimate, with an effective date of October 20, 2021, was (i) prepared by Judith St-Laurent, P.Geo (OGQ #1023)., B.Sc., Director of Resources Estimation at Osisko, and (ii) reviewed and approved by Pierre-Luc Richard, M.Sc., P.Geo (OGQ#1119), each of whom is a “qualified person” within the meaning of NI 43-101. Mr. Richard is an employee of BBA Inc. and is considered to be “independent” of Osisko for purposes of section 1.5 of NI 43-101. The scientific and technical content in this news release has been reviewed and approved by Mr. Mathieu Savard, P.Geo (OGQ #510), President of Osisko, who is a “qualified person” within the meaning of NI 43-101.

Quality Control and Reporting Protocols

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 greenstone belt, Urban Township, Eeyou Istchee James Bay, Québec, Canada. The mineral resource defined by Osisko, as disclosed in this news release and assuming a cut-off grade of 3.5 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 this news release, certain of which are described in this news release, will be further described in the full technical report being prepared for this updated mineral resource estimate in accordance with NI 43-101, and will be available on SEDAR (www.sedar.com) under the Corporation’s issuer profile within 45 days. 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, and Underdog. Mineralization is generally comprised of sub-vertical lenses following intrusive porphyry contacts plunging to the northeast. The resources are defined from surface to a depth of 1,600 metres, including the Triple 8 (TP8) zone. The resources excluding TP8 are defined from surface to a depth of 1,200 metres. The deposit remains open along strike and at depth. Mineralization has been identified near 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 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 the Urban Barry area and nearby Quévillon area (over 2,600 square kilometres).

 

Cautionary Statements Regarding Estimates of Mineral Resources

This news release uses the terms measured, indicated and inferred mineral resources as a relative measure of the level of confidence in the resource estimate. Readers are cautioned that mineral resources are not mineral reserves and that the economic viability of resources that are not mineral reserves has not been demonstrated. The mineral resource estimate disclosed in this news release may be materially affected by geology, environmental, permitting, legal, title, socio-political, marketing or other relevant issues. The mineral resource estimate is classified in accordance with the Canadian Institute of Mining, Metallurgy and Petroleum’s “CIM Definition Standards on Mineral Resources and Mineral Reserves” incorporated by reference into NI 43-101 (“CIM”). Under NI 43-101, estimates of inferred mineral resources may not form the basis of feasibility or pre-feasibility studies or economic studies except for preliminary economic assessments. Readers are cautioned not to assume that further work on the stated resources will lead to mineral reserves that can be mined economically.

 

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 MRE 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 MRE disclosed in this news release; the timing and ability of Osisko, if at all, to publish a feasibility study for the Windfall gold deposit; upgrading a inferred mineral resource to a measured mineral resource or indicated mineral resource category; future exploration activities, including drilling, at the Windfall gold deposit; the growth potential of the Windfall deposit and management’s expectations relating thereto; the potential for expansion of high-grade zones in Lynx to the East and down plunge; expected grade and resource growth; the deposit remaining open along strike to the northeast and at depth; cut-off grade and sensitivity analysis; 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
Chief Executive Officer
Office Telephone (416) 363-8653