Osisko Metals Incorporated announced an initial Inferred Mineral Resource Estimate at Mount Copper as part of the Gaspé Copper Project, located near Murdochville in the Gaspé Peninsula of Quebec. This resource is pit-constrained to mineralization surrounding the past-producing Mount Copper open pit mine (“Mount Copper Expansion Project”) and uses a base case of US$3.80/lb copper and a lower cut-off grade of 0.16% sulfide copper. It was estimated using data from historical drilling completed between the 1960's and 2019.

End-of-mine, existing historical mineral resources at Gaspé Copper that are not NI43-101 compliant are reported in Noranda/Falconbridge Annual Reports 1998-2000, Quebec government mining assessment reports and in Hussey & Bernard (SME Aug. 1998, p. 36-44). Regulatory authorities require that disclosure of historical resources by an issuer must be referenced, along with other requirements, by publicly available technical reports, and such reports on the historical estimates are not available.

The following disclosure therefore describes the remaining mineral deposits and areas of mineralization at Gaspé Copper and the Company believes that these offer excellent potential for additional resources. Osisko Metals' strategy at the present time is to focus on the economic viability of the Mount Copper sulfide resource only, and if this can be achieved, evaluation of the potential resources offered below will follow with additional drill programs. The deep-seated Porphyry Mountain deposit was discovered by Noranda Inc. in 1994. Porphyry-style stockwork Cu-Mo mineralization forms a roughly vertical, cylindrical deposit (approx.

800 m high, 400 m long and 350 m wide) that is located deep under Porphyry Mountain (located 1250 metres NE of the center of the Mount Copper open pit), at depths between 1200 and 2000 metres. The deposit remains open at depth. Previous mining at the Mount Copper open pit resulted in the stockpiling of oxidized copper mineralization approximately 1100 metres to the NW of the center of the open pit.

The stockpiles cover an area measuring 470,000 square metres with an average height of 25 metres. This material is potentially amenable to heap leaching and SX-EW recovery techniques and could eventually represent a low-cost opportunity for additional copper production if a heap leach operation can be successfully permitted. Residual underground skarn mineralization still remains in the form of pillars in the mined portion of the C Zone (grades of 1.5% to 2% copper), as well as massive sulfide/skarn mineralization in the deeper E Zone (grades of 3% to 4% copper) with residual resources reported in the E-38 zone.

Furthermore, significant historical drill intersections scattered within the 1600-metre-wide E Zone skarn aureole received limited follow-up and offer potential for further resource definition.