OSISKO INFILL DRILLING CONTINUES TO INTERSECT HIGH-GRADE AT LYNX

Includes 132 g/t Au Over 5.0 Metres, 51.0 g/t Au Over 6.3 Metres

(Toronto, June 17, 2019)  Osisko Mining Inc. (OSK:TSX. “Osisko” or the “Corporation”) is pleased to provide new infill drilling results from the ongoing definition and expansion program at its 100% owned Windfall gold project located in the Abitibi greenstone belt, Urban Township, Eeyou Istchee James Bay, Québec.  The program is currently focused on infill drilling within the main Windfall gold deposit and the adjacent Lynx deposit (located immediately NE of Windfall), exploration and expansion drilling on the main mineralized zones, and deep exploration in the central areas of the intrusive system. Significant new analytical results from 19 intercepts in 7 drill holes and 6 wedges from surface focused on Lynx infill drilling are presented below.  Additionally, 69 intercepts in 43 underground drill holes focused on 5 metre infill drilling, including the pending Lynx bulk sample area, are included in a second table below.

Highlights from new infill drilling results at Lynx include: 132 g/t Au over 5.0 metres in WST-19-0117; 51.0 g/t Au over 6.3 metres in OSK-W-19-909-W7; 56.2 g/t Au over 4.7 metres in WST-19-0106; 106 g/t Au over 2.0 metres in WST-19-0119; 82.9 g/t Au over 2.3 metres in WST-19-0113; 85.3 g/t Au over 2.0 metres in WST-19-0125; 36.0 g/t Au over 4.1 metres in OSK-W-18-1785-W1; 23.4 g/t Au over 6.3 metres in OSK-W-18-1539;  63.6 g/t Au over 2.1 metres in WST-19-0137; 59.3 g/t Au over 2.2 metres in WST-19-148;  37.0 g/t Au over 3.5 metres in WST-19-0130 and 42.1 g/t Au over 3.0 metres in WST-19-0093. Maps showing hole locations and full analytical results are available at www.osiskomining.com.

Surface Drilling

Hole No. From (m) To (m) Interval (m) Au (g/t) uncut Au (g/t)         cut to 100 g/t Area Zone
OSK-W-18-1539 910.7 917.0 6.3 23.4   Lynx Lynx
including 910.7 911.2 0.5 71.5
including 914.2 915.2 1.0 88.9
OSK-W-18-1785-W1 258.9 263.0 4.1 36.0 22.6 Lynx_305 Lynx
including 258.9 259.5 0.6 192 100
  275.0 277.3 2.3 27.4   Lynx_310 Lynx
OSK-W-19-1181-W5 991.7 993.9 2.2 19.6   Lynx_317 Lynx
including 993.4 993.9 0.5 74.2
  997.2 999.2 2.0 6.50   Lynx 4 Lynx
including 998.2 999.2 1.0 12.2
  1005.0 1009.7 4.7 13.4   Lynx_330 Lynx
including 1006.2 1007.0 0.8 47.7
OSK-W-19-1181-W8 879.8 882.0 2.2 20.5   Lynx_324 Lynx
including 879.8 880.4 0.6 54.2
Hole No. From (m) To (m) Interval (m) Au (g/t) uncut Au (g/t)         cut to 100 g/t Area Zone
OSK-W-19-1850 141.8 144.8 3.0 16.8   Lynx_304 Lynx
including 141.8 142.1 0.3 99.8
OSK-W-19-1852 154.7 156.8 2.1 13.7   Lynx_305 Lynx
including 155.4 156.1 0.7 35.9
OSK-W-19-1855 301.0 303.0 2.0 4.67   Lynx_305 Lynx
OSK-W-19-1857-W1 1230.8 1233.3 2.5 3.94   Lynx_313 Lynx
  1235.4 1237.6 2.2 3.31   Lynx_313 Lynx
OSK-W-19-1860 287.7 290.5 2.8 6.39   Lynx_305 Lynx
including 287.7 288.6 0.9 17.1
  294.5 298.4 3.9 13.0   Lynx_305 Lynx
including 297.0 297.7 0.7 42.4
OSK-W-19-1915 585.0 587.1 2.1 7.84   Lynx Lynx
including 585.0 585.4 0.4 40.7
OSK-W-19-1939 253.6 255.8 2.2 4.47   Lynx HW Lynx
OSK-W-19-909-W7 976.7 983.0 6.3 51.0 18 Lynx_313 Lynx
including 982.0 982.6 0.6 447 100
  985.0 987.1 2.1 14.3   Lynx_313 Lynx
OSK-W-19-961-W1 1075.0 1077.0 2.0 5.11   Lynx_312 Lynx

 

Underground drilling

Hole No. From (m) To (m) Interval (m) Au (g/t) uncut Au (g/t)         cut to 100 g/t Area Zone
WST-19-0089 75.4 77.6 2.2 4.05   Lynx_311 Lynx
including 75.4 76.0 0.6 10.9
WST-19-0090 85.0 87.4 2.4 5.23   Lynx_311 Lynx
including 85.7 86.5 0.8 15.3
WST-19-0091 85.5 89.8 4.3 21.5 17.5 Lynx_311 Lynx
including 85.5 86.1 0.6 129 100
WST-19-0092 87.0 89.0 2.0 3.33   Lynx_311 Lynx
including 88.1 88.4 0.3 17.5
WST-19-0093 86.3 89.3 3.0 42.1   Lynx_308 Lynx
WST-19-0097 65.9 68.0 2.1 14.2   Lynx_311 Lynx
including 65.9 66.5 0.6 46.3
WST-19-0098 66.0 68.7 2.7 38.7 25.6 Lynx_311 Lynx
including 66.6 67.2 0.6 159 100
WST-19-0099 76.5 78.5 2.0 28.5 15.7 Lynx_311 Lynx
including 77.9 78.2 0.3 185 100
WST-19-0100 69.4 72.5 3.1 34.1 18.6 Lynx_311 Lynx
including 72.2 72.5 0.3 260 100
WST-19-0101 73.0 75.0 2.0 7.66   Lynx_311 Lynx
including 74.0 74.3 0.3 47.9
WST-19-0102 65.6 68.1 2.5 6.12   Lynx_311 Lynx
including 66.2 66.5 0.3 48.7
WST-19-0106 65.0 68.0 3.0 10.2   Lynx_311 Lynx
including 66.8 67.3 0.5 36.9
  108.7 111.0 2.3 5.04   Lynx_310 Lynx
including 109.8 110.1 0.3 33.0
  126.0 130.7 4.7 56.2 10.4 Lynx_304 Lynx
including 126.6 127.0 0.4 639 100
WST-19-0107 66.0 68.6 2.6 9.94   Lynx_311 Lynx
including 67.8 68.6 0.8 25.8
WST-19-0108 67.1 69.4 2.3 22.5   Lynx_311 Lynx
including 67.6 68.5 0.9 54.7
WST-19-0111 70.4 72.5 2.1 13.3   Lynx_311 Lynx
including 71.8 72.5 0.7 37.8
WST-19-0112 70.8 73.1 2.3 16.0   Lynx_311 Lynx
WST-19-0113 75.4 77.7 2.3 82.9 20.7 Lynx_311 Lynx
including 75.4 75.8 0.4 458 100
WST-19-0114 71.0 73.3 2.3 5.89   Lynx_311 Lynx
including 71.7 72.4 0.7 18.3
WST-19-0115 72.4 74.8 2.4 17.1   Lynx_311 Lynx
including 73.0 73.6 0.6 68.1
WST-19-0116 87.6 91.1 3.5 26.9 12.6 Lynx Lynx
including 89.0 89.3 0.3 267 100
  99.0 104.2 5.2 3.91   Lynx_310 Lynx
including 103.6 104.2 0.6 19.6
WST-19-0117 84.5 89.5 5.0 132 34.2 Lynx_308 Lynx
including 85.5 86.0 0.5 922 100
WST-19-0118 44.0 47.0 3.0 18.0   Lynx_311 Lynx
including 46.4 47.0 0.6 81.9
WST-19-0119 55.7 57.9 2.2 3.94   Lynx_311 Lynx
including 56.4 56.9 0.5 16.6
  87.0 89.0 2.0 106 25.2 Lynx_310 Lynx
including 88.5 89.0 0.5 425 100
  97.6 99.7 2.1 4.09   Lynx Lynx
WST-19-0120 59.2 63.2 4.0 7.34   Lynx_311 Lynx
including 59.2 59.9 0.7 29.7
  128.3 130.7 2.4 10.5   Lynx_304 Lynx
WST-19-0121 54.4 58.0 3.6 8.66   Lynx_308 Lynx
WST-19-0122 44.0 46.0 2.0 32.9 15.3 Lynx_311 Lynx
including 44.8 45.1 0.3 217 100
  55.0 57.0 2.0 50.8 26.2 Lynx_308 Lynx
including 55.8 56.3 0.5 199 100
WST-19-0123 58.5 61.2 2.7 3.51   Lynx_308 Lynx
including 60.6 61.2 0.6 9.03
WST-19-0125 47.0 49.0 2.0 85.3 31.1 Lynx_311 Lynx
including 47.5 48.0 0.5 317 100
  60.0 62.0 2.0 7.36   Lynx_308 Lynx
WST-19-0126 42.0 44.0 2.0 6.60   Lynx Lynx
including 42.9 43.5 0.6 21.2
  50.0 52.5 2.5 11.7   Lynx_311 Lynx
including 50.4 50.8 0.4 72.2
WST-19-0128 51.4 54.4 3.0 10.7   Lynx_311 Lynx
including 54.1 54.4 0.3 80.2    
WST-19-0129 60.5 62.6 2.1 4.59   Lynx_311 Lynx
including 62.3 62.6 0.3 30.7
WST-19-0130 50.8 54.3 3.5 37.0 24.3 Lynx_311 Lynx
including 53.6 54.3 0.7 164 100
WST-19-0132 72.1 74.1 2.0 27.3   Lynx_310 Lynx
including 72.1 73.1 1.0 54.2
  78.5 80.7 2.2 3.03   Lynx Lynx
  104.6 107.3 2.7 6.68   Lynx_304 Lynx
including 106.0 106.5 0.5 19.8
  122.0 124.0 2.0 4.17   Lynx Lynx
including 123.5 124.0 0.5 14.2
WST-19-0133 45.0 47.4 2.4 16.2   Lynx Lynx
including 45.0 45.4 0.4 86.0
  67.2 69.3 2.1 4.63   Lynx Lynx
including 68.2 68.5 0.3 30.7
WST-19-0136 41.1 45.1 4.0 8.51   Lynx_308 Lynx
  46.0 48.0 2.0 4.21   Lynx_308 Lynx
  67.7 69.8 2.1 15.9   Lynx_310 Lynx
  94.8 102.2 7.4 5.98   Lynx_304 Lynx
including 95.5 95.8 0.3 34.6
WST-19-0137 50.4 56.3 5.9 17.5 16.0 Lynx_308 Lynx
including 52.4 53.0 0.6 51.8  
including 55.9 56.3 0.4 124 100    
  107.0 109.1 2.1 63.6 50.1 Lynx_304 Lynx
WST-19-0139 52.2 54.6 2.4 4.08   Lynx_308 Lynx
WST-19-0141 53.0 55.4 2.4 3.91   Lynx_308 Lynx
including 53.7 54.4 0.7 11.8
  59.0 61.1 2.1 10.9   Lynx_308 Lynx
including 59.0 59.3 0.3 73.7
  88.4 90.5 2.1 18.4   Lynx_305 Lynx
  103.2 105.4 2.2 5.89   Lynx_304 Lynx
including 105.1 105.4 0.3 42.7
WST-19-0142A 103.0 105.0 2.0 5.92   Lynx_305 Lynx
including 103.6 103.9 0.3 38.4
WST-19-0143 69.7 71.8 2.1 16.1   Lynx_308 Lynx
including 69.7 70.4 0.7 48.2
  81.0 83.0 2.0 4.85   Lynx Lynx
including 81.7 82.1 0.4 23.3
  117.5 119.7 2.2 3.27   Lynx_304 Lynx
WST-19-0148 55.5 57.6 2.1 10.5   Lynx_311 Lynx
including 56.8 57.2 0.4 51.7
  77.8 80.1 2.3 11.6   Lynx Lynx
including 79.7 80.1 0.4 35.4
  112.0 114.2 2.2 59.3 41.8 Lynx_305 Lynx
including 112.0 112.7 0.7 155 100
  118.8 121.2 2.4 6.31   Lynx_304 Lynx
including 120.5 121.2 0.7 18.6
WST-19-0149 76.0 78.4 2.4 4.03   Lynx_310 Lynx
WST-19-0155 51.0 53.3 2.3 5.60   Lynx_311 Lynx
  67.0 69.0 2.0 13.8   Lynx Lynx
including 68.0 69.0 1.0 27.3

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

 

 

 

Surface Drilling

Hole Number Azimuth (°) Dip Length (m) UTM E UTM N Elevation Section
OSK-W-18-1539 145 -52 1119 453374 5435448 402 3750
OSK-W-18-1785-W1 334 -59 375 453425 5434953 396 3550
OSK-W-19-1181-W5 133 -58 1115 453789 5435790 401 4275
OSK-W-19-1181-W8 133 -58 1035 453789 5435790 401 4275
OSK-W-19-1850 329 -58 270 453320 5434954 398 3475
OSK-W-19-1852 330 -58 300 453312 5434949 397 3450
OSK-W-19-1855 124 -45 351 453178 5435190 404 3450
OSK-W-19-1857-W1 108 -58 1455 453525 5435704 405 4000
OSK-W-19-1860 124 -45 333 453186 5435200 404 3475
OSK-W-19-1915 350 -70 651 454120 5435103 397 4225
OSK-W-19-1939 126 -45 519 453283 5435278 401 3600
OSK-W-19-909-W7 131 -55 1080 453683 5435677 401 4125
OSK-W-19-961-W1 141 -54 1182 453438 5435479 401 3825

 

Underground drilling

Hole Number Azimuth (°) Dip Length (m) UTM E UTM N Elevation Section
(°) (m)
WST-19-0089 131 -14 100 453219 5435116 223 3450
WST-19-0090 127 -30 99 453219 5435116 223 3450
WST-19-0091 123 -26 100 453219 5435116 223 3450
WST-19-0092 123 -22 108 453219 5435116 223 3450
WST-19-0093 123 -13 121 453219 5435116 223 3450
WST-19-0097 152 -12 97 453218 5435115 223 3450
WST-19-0098 157 -14 85 453218 5435115 223 3450
WST-19-0099 131 -28 100 453219 5435116 223 3450
WST-19-0100 137 -20 91 453219 5435116 224 3450
WST-19-0101 137 -25 90 453219 5435116 223 3450
WST-19-0102 162 -12 85 453218 5435115 224 3450
WST-19-0106 152 -18 136 453218 5435115 223 3450
WST-19-0107 152 -22 136 453218 5435115 223 3450
WST-19-0108 147 -19 136 453219 5435115 223 3450
WST-19-0111 141 -23 132 453219 5435116 223 3450
WST-19-0112 141 -28 139 453219 5435116 223 3450
WST-19-0113 137 -29 139 453219 5435116 223 3450
WST-19-0114 147 -33 136 453219 5435116 223 3450
WST-19-0115 141 -32 141 453219 5435116 223 3450
WST-19-0116 137 -33 145 453219 5435116 223 3450
WST-19-0117 121 -1 163 453220 5435116 224 3450
WST-19-0118 161 -14 109 453252 5435110 206 3475
WST-19-0119 144 -35 157 453252 5435110 206 3475
WST-19-0120 134 -33 136 453253 5435110 206 3475
WST-19-0121 134 3 132 453253 5435110 206 3475
WST-19-0122 137 -7 138 453253 5435110 206 3475
WST-19-0123 132 -17 135 453253 5435110 206 3475
WST-19-0125 150 -17 64 453252 5435110 206 3475
WST-19-0126 143 -7 70 453252 5435110 206 3475
WST-19-0128 137 -28 139 453253 5435110 205 3475
WST-19-0129 151 -27 67 453252 5435110 205 3475
WST-19-0130 154 -33 142 453252 5435110 205 3475
WST-19-0132 143 16 129 453252 5435110 206 3475
WST-19-0133 154 27 129 453252 5435110 207 3475
WST-19-0136 149 12 108 453266 5435107 206 3500
WST-19-0137 136 13 129 453268 5435108 206 3500
WST-19-0139 134 -8 121 453266 5435107 206 3500
WST-19-0141 134 -22 120 453266 5435107 205 3500
WST-19-0142A 136 -30 123 453267 5435108 205 3500
WST-19-0143 134 -38 135 453266 5435107 205 3500
WST-19-0148 128 -39 145 453268 5435109 204 3500
WST-19-0149 159 -28 90 453252 5435110 205 3475
WST-19-0155 124 -32 137 453268 5435110 204 3500

 

OSK-W-18-1539 intersected 23.4 g/t Au over 6.3 metres. Mineralization is composed of local visible gold, up to 20% disseminated pyrite, up to 10% disseminated sphalerite, 3% chalcopyrite, 3% molybdenite and traces of arsenopyrite within a moderate silica, sericite and fuchsite altered rhyolite.

 

OSK-W-18-1785-W1 intersected two intervals: 36.0 g/t Au over 4.1 metres and 27.4 g/t Au over 2.3 metres. The first interval contains local visible gold, up to 15% finely disseminated pyrite, up to 1.5% sphalerite within pervasive silica flooding with quartz-tourmaline veins. The mineralization is at the contact between a moderate fuchsite and sericite altered rhyolite and a felsic porphyritic dike. The second interval contains local visible gold, up to 15% finely disseminated pyrite, trace sphalerite and pyrite tourmaline stringers within a strong silica and moderate sericite altered felsic porphyritic dike.

 

OSK-W-19-1181-W5 intersected three intervals: 19.6 g/t Au over 2.2 metres, 6.50 g/t Au over 2.0 metres and 13.4 g/t Au over 4.7 metres. The first interval contains up to 3% stringer, clustered, and disseminated pyrite and quartz-tourmaline veins at the contact between a moderate sericite altered gabbro and a moderate fuchsite and sericite altered rhyolite. The second interval contains 1% pyrite in clusters and stringers within a strong sericite altered rhyolite. The last interval is composed of up to 5% pyrite clusters within a moderate sericite altered rhyolite.

 

OSK-W-19-1181-W8 intersected 20.5 g/t Au over 2.2 metres. The mineralization is composed of 4% pyrite stringers with a tourmaline breccia and quartz-carbonate veins hosted in a moderate chlorite and weak fuchsite altered rhyolite.

 

OSK-W-19-1850 intersected 16.8 g/t Au over 3.0 metres. The mineralization is composed of up to 2% pyrite stringers within a strong chlorite and moderate carbonate altered gabbro.

 

OSK-W-19-1852 intersected 13.7 g/t Au over 2.1 metres. The mineralization is composed of up to 5% disseminated, clustered, and stringer pyrite, and trace sphalerite with pervasive silica flooding hosted in a moderate sericite altered rhyolite.

 

OSK-W-19-1855 intersected 4.67 g/t Au over 2.0 metres. The mineralization is composed of 2% disseminated pyrite and tourmaline ptygmatic veins within a strong silica altered felsic fragmental intrusion.

 

OSK-W-19-1857-W1 intersected two intervals: 3.94 g/t Au over 2.5 metres and 3.31 g/t Au over 2.2 metres. The two intervals contain up to 7% pyrite stringers and clusters, quartz-tourmaline veins and trace chalcopyrite at the contact between a moderate silica and weak sericite altered rhyolite with a strong sericite altered gabbro. Both units have weak fuchsite alteration.

 

OSK-W-19-1860 intersected two intervals: 6.39 g/t Au over 2.8 metres and 13.0 g/t Au over 3.9 metres. The first interval contains up to 3% disseminated pyrite and quartz-tourmaline veins hosted in a moderate silica and sericite altered felsic fragmental intrusion. The second interval contains up to 4% finely disseminated pyrite, smoky quartz veins and local visible gold within a strong silica and weak sericite altered rhyolite.

 

OSK-W-19-1915 intersected 7.84 g/t Au over 2.1 metres. The mineralization is composed of local visible gold with pervasive silica flooding, 2% pyrite stringers and clusters hosted in a weak sericite and carbonate altered felsic fragmental intrusion.

 

OSK-W-19-1939 intersected 4.47 g/t Au over 2.2 metres. The mineralization is composed of 3% pyrite stringers and clusters hosted in a moderate sericite and weak silica altered felsic intrusion.

 

OSK-W-19-909-W7 intersect two intervals: 51.0 g/t Au over 6.3 metres and 14.3 g/t Au over 2.1 metres. The first interval contains local visible gold and electrum with pervasive silica flooding, 20% pyrite clusters, trace chalcopyrite and smoky quartz veins hosted at the contact between a strong silica altered rhyolite and a felsic porphyritic intrusion. The second interval contains 1% pyrite stringers within a strong silica, strong sericite and weak fuchsite altered felsic porphyritic dike.

 

OSK-W-19-961-W1 intersected 5.11 g/t Au over 2.0 metres. The mineralization is composed of 5% pyrites clusters and smoky quartz veins within a silica altered rhyolite.

 

WST-19-0089 intersected 4.05 g/t Au over 2.2 metres. The mineralization is composed of 1% pyrite stringer and 2% disseminated pyrite within a moderate silica and sericite altered rhyolite. WST-19-0089 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0090 intersected 5.23 g/t Au over 2.4 metres. The mineralization includes 1% pyrite stringers and 2% disseminated pyrite within a moderate silica and sericite altered rhyolite. WST-19-0090 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0091 intersected 21.5 g/t Au over 4.3 metres. The mineralization is composed of local visible gold, 2% pyrite stringers and 15% sphalerite hosted in sericite, silica and fuchsite altered rhyolite. WST-19-0091 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0092 intersected 3.33 g/t Au over 2.0 metres. The mineralization is composed of 1% pyrite stringers with pervasive silica flooding within a moderate sericite and silica altered rhyolite. WST-19-0092 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0093 intersected 42.1 g/t Au over 3.0 metres. The mineralization is composed of local visible gold in fracture filling, up to 2% pyrite stringers with pervasive silica flooding, hosted in a moderate silica and weak fuchsite altered felsic fragmental intrusion. WST-19-0093 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0097 intersected 14.2 g/t Au over 2.1 metres. The mineralization is composed of trace pyrite stringers and clusters within a weak silica and sericite altered rhyolite. WST-19-0097 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0098 intersected 38.7 g/t Au over 2.7 metres. The mineralization is composed of local visible gold, up to 3% disseminated and stringer pyrite, and trace chalcopyrite and sphalerite hosted in a moderate fuchsite and silica altered rhyolite. WST-19-0098 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0099 intersected 28.5 g/t Au over 2.0 metres. The mineralization is composed of local visible gold, 1% disseminated pyrite and trace chalcopyrite with pervasive silica flooding hosted in a moderate sericite and silica altered rhyolite. WST-19-0099 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0100 intersected 34.1 g/t Au over 3.1 metres. The mineralization is composed of local visible gold, 1% pyrite stringers and clusters with pervasive silica flooding hosted in a weak silica and sericite altered rhyolite. WST-19-0100 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0101 intersected 7.66 g/t Au over 2.0 metres. The mineralization is composed of 2% pyrite-tourmaline stringers, 1% pyrite clusters and trace chalcopyrite within pervasive silica flooding and hosted in a weak silica and sericite altered rhyolite. WST-19-0101 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0102 intersected 6.12 g/t Au over 2.5 metres. The mineralization is composed of 2% pyrite clusters and 1% pyrite-tourmaline stringers hosted at the contact between a weak silica and sericite altered rhyolite and a weak sericite altered felsic porphyritic intrusion. WST-19-0102 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0106 intersected three interval: 10.2 g/t Au over 3.0 metres, 5.04 g/t Au over 2.3 metres and 56.2 g/t Au over 4.7 metres. The first interval is composed of up to 5% disseminated, clustered, and stringer pyrite associated with pervasive silica flooding hosted in a sericitized felsic porphyritic intrusion. The second interval contains trace disseminated and clustered pyrite within a moderate sericite and weak silica altered rhyolite. The last interval contains local visible gold, 3% pyrite clusters, trace sphalerite and chalcopyrite associated with pervasive silica flooding hosted in a moderate silica and sericite altered felsic porphyritic intrusion. WST-19-0106 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0107 intersected 9.94 g/t Au over 2.6 metres. The mineralization is composed of up to 3% pyrite clusters and stringers, traces sphalerite with pervasive silica flooding hosted in a moderate sericite altered rhyolite. WST-19-0107 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0108 intersected 22.5 g/t Au over 2.3 metres. The mineralization is composed of up to 5% pyrite-tourmaline stringers and clusters hosted in a weak sericite and silica altered rhyolite. WST-19-0108 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0111 intersected 13.3 g/t Au over 2.1 metres. The mineralization is composed of local visible gold, 1% disseminated pyrite with pervasive silica flooding hosted in a moderate silica and fuchsite altered felsic porphyritic intrusion. WST-19-0111 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0112 intersected 16.0 g/t Au over 2.3 metres. The mineralization is composed of 7% pyrite clusters with pervasive silica flooding hosted at the contact between a felsic porphyritic intrusion and a rhyolite. WST-19-0112 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0113 intersected 82.9 g/t Au over 2.3 metres. The mineralization is composed of local visible gold, 3% pyrite clusters and stringers with trace sphalerite in pervasive silica flooding hosted in a moderate sericite altered rhyolite. WST-19-0113 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0114 intersected 5.89 g/t Au over 2.3 metres. The mineralization is composed of up to 5% finely disseminated pyrite with pervasive silica flooding hosted in weak fuchsite, sericite and silica altered rhyolite. WST-19-0114 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0115 intersected 17.1 g/t Au over 2.4 metres. The mineralization is composed of up to 5% finely disseminated and clustered pyrite hosted in a moderate silica, and weak sericite and fuchsite altered rhyolite. WST-19-0115 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0116 intersected 26.9 g/t Au over 3.5 metres and 3.91 g/t Au over 5.2 metres. The first interval contains 3% pyrite clusters and stringers with pervasive silica flooding hosted in a moderate sericite altered rhyolite. The second interval contains trace disseminated, clustered, and stringer pyrite within a moderate sericite and weak silica altered rhyolite. WST-19-0115 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0117 intersected 132 g/t Au over 5.0 metres. The mineralization is composed of local visible gold, 2% pyrite stringers and clusters, traces chalcopyrite and quartz-tourmaline veins hosted in a weak sericitized and silica altered felsic intrusion. WST-19-0117 was drilled from underground drill station RA-180-190-E located 180 metres below surface from section 3450E.

 

WST-19-0118 intersected 18.0 g/t Au over 3.0 metres. The mineralization is composed of up to 10% pyrite stringers and clusters and 1% sphalerite in fracture filling at the contact between a sericite altered felsic intrusion and a sericite altered rhyolite. WST-19-0118 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0119 intersected 3.94 g/t Au over 2.2 metres, 106 g/t Au over 2.0 metres and 4.09 g/t Au over 2.1 metres. The first interval contains up to 30% fine disseminated, clustered, and stringer  pyrite with quartz-tourmaline veins hosted in a moderate sericite altered rhyolite. The second and third intervals contains local visible gold, 1% fine disseminated pyrite and quartz-carbonate veins hosted in a weak sericite and silica altered rhyolite. WST-19-0119 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0120 intersected 7.34 g/t Au over 4.0 metres and 10.5 g/t Au over 2.4 metres. The first interval contains up to 3% disseminated and clustered pyrite, trace sphalerite and tourmaline ptygmatic veins within a weak fuchsite and moderate sericite altered rhyolite. WST-19-0120 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0121 intersected 8.66 g/t Au over 3.6 metres. The mineralization is composed of up to 3% disseminated and stringer pyrite and up to 10% quartz-tourmaline ptygmatic veins within a sericite altered felsic intrusion. WST-19-0121 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0122 intersected 32.9 g/t Au over 2.0 metres and 50.8 g/t Au over 2.0 metres. The first interval contains up to 20% finely disseminated pyrite with pervasive silica flooding hosted in a moderate sericite and strong silica altered rhyolite. The second interval is composed of 10% pyrite stringers and smoky quartz veins within a moderate sericite altered rhyolite. WST-19-0122 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0123 intersected 3.51 g/t Au over 2.7 metres. The mineralization is composed of 3% pyrite stingers and clusters with pervasive silica flooding hosted in a strong silica and sericite altered rhyolite. WST-19-0123 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0125 intersected 85.3 g/t Au over 2.0 metres and 7.36 g/t Au over 2.0 metres. The first interval contains local visible gold and up to 10% finely disseminated pyrite with pervasive silica flooding hosted in a strong fuchsite and silica altered rhyolite. The second interval is composed of 20% finely disseminated pyrite within a strong sericite, silica and a moderate fuchsite altered rhyolite. WST-19-0125 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0126 intersected 6.60 g/t Au over 2.0 metres and 11.7 g/t Au over 2.5 metres. The first interval contains 4% disseminated and clustered pyrite hosted in a weak sericite and silica altered rhyolite. The second interval contains local visible gold, 4% pyrite tourmaline veins, up to 20% finely disseminated pyrite and trace sphalerite hosted in a moderate silica and weak sericite altered rhyolite. WST-19-0126 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0128 intersected 10.7 g/t Au over 3.0 metres. The mineralization is composed of up to 3% pyrite clusters and stringers with pervasive silica flooding and quartz-carbonate veins hosted in a weak silica and sericite altered rhyolite. WST-19-0128 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0129 intersected 4.59 g/t Au over 2.1 metres. The mineralization is composed of 1% pyrite clusters within a weak silica altered rhyolite. WST-19-0129 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0130 intersected 37.0 g/t Au over 3.5 metres. The mineralization is composed of up to 3% pyrite clusters and local visible gold with pervasive silica flooding and trace sphalerite hosted in strong silica and fuchsite altered rhyolite. WST-19-0130 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0132 intersected four intervals: 27.3 g/t Au over 2.0 metres, 3.03 g/t Au over 2.2 metres, 6.68 g/t Au over 2.7 metres and 4.17 g/t Au over 2.0 metres. The first interval contains 1% pyrite clusters within a weak sericite altered felsic fragmental intrusion. The second interval contains 2% pyrite clusters with pervasive silica flooding and up to 20% quartz-tourmaline ptygmatic veins within a sericitized felsic fragmental intrusion. The third interval is composed of 2% pyrite clusters hosted in a strong silica and weak sericite altered rhyolite. The last interval contains 1% pyrite clusters with 15% smoky quartz veins hosted in a strong sericite and silica altered rhyolite. WST-19-0128 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0133 intersected 16.2 g/t Au over 2.4 metres and 4.63 g/t Au over 2.1 metres. The first interval contains 2% pyrite clusters within a moderate sericite altered felsic fragmental intrusion. The second interval is composed of 3% disseminated pyrite with pervasive silica flooding within a weak sericite altered felsic fragmental intrusion. WST-19-0133 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0136 intersected four intervals: 8.51 g/t Au over 4.0 metres, 4.21 g/t Au over 2.0 metres, 15.9 g/t Au over 2.1 metres and 5.98 g/t Au over 7.4 metres. The first interval contains up to 5% disseminated pyrite, traces of sphalerite and smoky quartz veins within a weak silica and sericite altered felsic fragmental intrusion. The second interval contains 2% pyrite stringers hosted in a moderate silica altered felsic intrusion. The third interval is composed of 5% disseminated pyrite with pervasive silica flooding, local visible gold and quartz-tourmaline veins within a moderate silica and sericite altered felsic intrusion. The last interval contains local visible gold, 10% pyrite and smoky quartz veins hosted in a moderate sericite and silica altered felsic porphyritic intrusion. WST-19-0136 was drilled from underground drill station AN-195-265-S located 195 metres below surface from section 3500E.

 

WST-19-0137 intersected two intervals: 17.5 g/t Au over 5.9 metres and 63.6 g/t Au over 2.1 metres. The first interval contains local visible gold, 1% disseminated and stringer pyrite within a moderate sericite and silica altered felsic fragmental intrusion. The second interval contains local visible gold and electrum, 4% finely disseminated pyrite and trace chalcopyrite within a fuchsite, silica and sericite altered rhyolite. WST-19-0137 was drilled from underground drill station AN-195-265-S located 195 metres below surface from section 3500E.

 

WST-19-0139 intersected 4.08 g/t Au over 2.4 metres. The mineralization is composed of 5% disseminated pyrite with pervasive silica flooding within a moderate fuchsite, sericite and silica altered felsic intrusion. WST-19-0139 was drilled from underground drill station AN-195-265-S located 195 metres below surface from section 3500E.

 

WST-19-0141 intersected four intervals: 3.91 g/t Au over 2.4 metres, 10.9 g/t Au over 2.1 metres, 18.4 g/t Au over 2.1 metres and 5.89 g/t Au over 2.2 metres. The first interval contains trace pyrite stringers within a moderate sericite altered rhyolite. The second interval contains local visible gold, 3% finely disseminated pyrite and quartz-tourmaline veins hosted in a sericite altered rhyolite. The third interval contains up to 5% finely disseminated and clustered pyrite hosted in a moderate silica altered rhyolite. The last interval is composed of 4% finely disseminated pyrite with pervasive silica flooding within a moderate sericite and silica altered rhyolite. WST-19-0141 was drilled from underground drill station AN-195-265-S located 195 metres below surface from section 3500E.

 

WST-19-0142A intersected 5.92 g/t Au over 2.0 metres. The mineralization is composed of 5% disseminated pyrite and ptygmatic tourmaline veins within a strong silica altered rhyolite. WST-19-0142A was drilled from underground drill station AN-195-265-S located 195 metres below surface from section 3500E.

 

WST-19-0143 intersected three intervals: 16.1 g/t Au over 2.1 metres, 4.85 g/t Au over 2.0 metres and 3.27 g/t Au over 2.2 metres. The first interval contains local visible gold, trace pyrite clusters with pervasive silica flooding hosted in a moderate silica and sericite altered rhyolite. The second interval contain local visible gold with quartz-carbonate veins hosted in a moderate sericite altered rhyolite. The last interval contains 2% disseminated pyrite and quartz-carbonate veins hosted in a sericitized felsic fragmental intrusion. WST-19-0143 was drilled from underground drill station AN-195-265-S located 195 metres below surface from section 3500E.

 

WST-19-0148 intersected four intervals: 10.5 g/t Au over 2.1 metres, 11.6 g/t Au over 2.3 metres, 59.3 g/t Au over 2.2 metres and 6.31 g/t Au over 2.4 metres. The first interval contains up to 2% pyrite stringers and ptygmatic tourmaline veins within a moderate sericite altered rhyolite. The second interval is composed of 4% disseminated, clustered, and stringer pyrite with pervasive silica flooding, quartz-tourmaline veins and trace sphalerite within a moderate sericite altered rhyolite. The third interval contains local visible gold, up to 9% disseminated and stringer pyrite and up to 3% sphalerite hosted in a strong fuchsite and silica altered rhyolite. The last interval contains up to 5% pyrite stringers and ptygmatic quartz-tourmaline veins at the contact between a felsic intrusion and a rhyolite. WST-19-0148 was drilled from underground drill station AN-195-265-S located 195 metres below surface from section 3500E.

 

WST-19-0149 intersected 4.03 g/t Au over 2.4 metres. The mineralization is composed of up to 1% pyrite stringers and clusters, and 3% quartz-carbonate veins hosted in a weak sericite altered rhyolite. WST-19-0149 was drilled from underground drill station RE-195-265-O located 195 metres below surface from section 3475E.

 

WST-19-0155 intersected 5.60 g/t Au over 2.3 metres and 13.8 g/t Au over 2.0 metres. The first interval contains 3% pyrite stringers with pervasive silica flooding and quartz-carbonate veins within a strong silica altered rhyolite. The second interval contains 1% pyrite stringers within a week silica altered rhyolite. WST-19-0155 was drilled from underground drill station AN-195-265-S located 195 metres below surface from section 3500E.

Qualified Person

The scientific and technical content of this news release has been reviewed, prepared and approved by Mr. Louis Grenier, M.Sc.A., P.Geo. (OGQ 800), Project Manager of Osisko’s Windfall Lake gold project, who is a “qualified person” as defined by National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI 43-101”).

 

Quality Control and Reporting Protocols

True width determination is estimated at 55-80% of the reported core length interval for the zone. Assays are uncut except where indicated. Intercepts occur within geological confines of major zones but have not been correlated to individual vein domains at this time. Reported intervals include minimum weighted averages of 3.0 g/t Au diluted over core lengths of at least 2.0 metres. All NQ core assays reported were obtained by either 1-kilogram screen fire assay or standard 50-gram fire-assaying-AA finish or gravimetric finish at (i) ALS Laboratories in Val d’Or, Québec, Thunder Bay, Ontario, Sudbury, Ontario or Vancouver, British Colombia, or (ii) Bureau Veritas in Timmins, Ontario. The 1-kilogram screen assay method is selected by the geologist when samples contain coarse gold or present a higher percentage of pyrite than surrounding intervals. Selected samples are also analyzed for multi-elements, including silver, using an Aqua Regia-ICP-AES method at ALS Laboratories. Drill program design, Quality Assurance/Quality Control (“QA/QC”) and interpretation of results is performed by qualified persons employing a QA/QC program consistent with NI 43-101 and industry best practices. Standards and blanks are included with every 20 samples for QA/QC purposes by the Corporation as well as the lab. Approximately 5% of sample pulps are sent to secondary laboratories for check assay.

 

About the Windfall Lake Gold Deposit

The Windfall Lake 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 Windfall Lake Technical Report (as defined below) and November 27, 2018 Lynx resource update, comprises 2,874,000 tonnes at 8.17 g/t Au (754,000 ounces) in the indicated mineral resource category and 10,352,000 tonnes at 7.11 g/t Au (2,366,000 ounces) in the inferred mineral resource category. For details regarding the key assumptions, parameters and methods used to estimate the mineral resources presented in respect of the Windfall Lake gold project, please see the technical report entitled “Technical Report and Mineral Resource Estimate for the Windfall Lake Project, Windfall Lake and Urban-Barry Properties” and dated June 12, 2018 (effective date of May 14, 2018), which has been prepared by InnovExplo Inc. from Val-d’Or, Québec (the “Windfall Lake Technical Report”) and the press release “Osisko Releases Mineral Resource Update for Lynx” dated November 27, 2018, which has been prepared by Osisko and reviewed and approved by Micon International, Ltd. from Toronto, Ontario. The Windfall Lake Technical Report and press release are available on Osisko’s website at www.osiskomining.com and on SEDAR under Osisko’s issuer profile at www.sedar.com. The Windfall Lake gold deposit is currently one of the highest-grade resource-stage gold projects in Canada. Mineralization occurs in four principal zones: Lynx, Zone 27, Caribou and Underdog. All zones comprise sub-vertical lenses following intrusive porphyry contacts plunging to the northeast. The deposit is well defined from surface to a depth of 900 metres and remains open along strike and at depth. Mineralization has been identified 30 metres from surface in some areas and as deep as 2,000 metres in others, with significant potential to extend mineralization down-plunge and at depth.

 

About Osisko Mining Inc.

Osisko is a mineral exploration company focused on the acquisition, exploration, and development of precious metal resource properties in Canada. Osisko holds a 100% interest in the high-grade Windfall Lake 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 2,700 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. The information in this news release about the Windfall Lake gold deposit being one of the highest grade resource-stage gold projects in Canada; the significance of results from the new infill drilling and ongoing drill definition and expansion program at the Windfall Lake gold project; the significance of assay results presented in this news release; the deposit remaining open along strike and at depth; potential depth extensions of the mineralized zones down-plunge and at depth; the actual mineralization of local visible gold; the current 800,000 metre drill program; the type of drilling included in the drill program; potential mineralization; the potential to extend mineralization up and down-plunge and at depth at the Windfall Lake gold deposit; the ability to realize upon any mineralization in a manner that is economic; the ability to complete any proposed exploration activities and the results of such activities, including the continuity or extension of any mineralization; and any other information herein that is not a historical fact may be “forward-looking information”. Any statement that involves discussions with respect to 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”, “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 forward-looking information is based on reasonable assumptions and estimates of management of the Corporation at the time such assumptions and estimates were made, and involves known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of Osisko to be materially different from any future results, performance or achievements expressed or implied by such forward-looking information. 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 interests in the Windfall Lake gold project; the ability of the Corporation to obtain required approvals and complete transactions on terms announced; 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.

 

For further information please contact:

John Burzynski
President and Chief Executive Officer

Telephone: (416) 363-8653