Expansion Drill Program At The Windfall Gold Project

TORONTO - Osisko Mining Inc. reported new infill drilling results from the definition and expansion drill program at its 100% owned Windfall gold project located in the Abitibi greenstone belt, Urban Township, Eeyou Istchee James Bay, Québec. Operations are temporarily suspended in respect of the Government of Québec’s closure of all non-essential business in effort to contain COVID-19. Osisko is ready to resume drilling activities at Windfall once the temporary suspension is lifted. Drilling will remain focused on the Lynx deposit, exploration on the main mineralized zones, and deep exploration in the central areas of the mineralized system.

Significant new analytical results are presented below and include 35 intercepts in 7 drill holes, 8 wedges and one extension of a previous drilled hole.  All intercepts are located outside the February 2020 mineral resource estimate wireframes and represent expansion of known mineralized zones. Selected high-grade intercepts include: 143 g/t Au over 2.0 meters and 64.4 g/t Au over 2.2 meters in OSK-W-19-2197-W1; 35.0 g/t Au over 5.3 meters in OSK-W-20-2123-W4; 39.8 g/t Au over 2.3 meters in OSK-W-20-2139-W6; and 37.3 g/t Au over 2.4 metres in WST-20-0339.

Mineralization in the Lynx zone is typically characterized by trace to 15% disseminated, clustered or stringer pyrite (locally up to 70%), local visible gold, trace to 3% sphalerite, chalcopyrite, and galena, local ptygmatic pyrite-tourmaline or tourmaline veinlets, quartz-carbonate veins (locally crustiform), smoky quartz veins and veinlets, and local chlorite-calcite or quartz-carbonate chlorite fracture filling. Alteration consists of weak to strong sericite, weak to strong silica with areas of local pervasive silica flooding, weak to moderate chlorite and carbonate, and locally weak to strong fuchsite. Mineralization is hosted in or at the contacts of felsic porphyritic or fragmental intrusions with rhyolites, andesites (locally bleached), or gabbros.

Mineralization in the Triple Lynx zone is typically characterized by trace to 30% disseminated, clustered or stringer pyrite, local visible gold, trace sphalerite, chalcopyrite, and galena, local quartz-tourmaline veins (up to 20%), local ptygmatic tourmaline veins, and local smoky quartz and quartz-carbonate veins. Alteration consists of weak to strong sericite, weak to strong silica with areas of local pervasive silica flooding, weak to moderate chlorite and carbonate, and locally weak to strong fuchsite. Mineralization is hosted in or at the contacts of felsic porphyritic dikes with rhyolites (locally bleached) or gabbros.