Includes 15.6 Metres Averaging 1.47% Cu and 8.5 g/t Ag

E Zone Skarn Returns 29.7 Metres Averaging 1.92% Cu and 15.2 g/t Ag

Infill Drilling Continues to Extend Deposit at Depth Below 2024 MRE

Osisko Metals Incorporated (TSX-V: OM) (OTCQX: OMZNF) (FRANKFURT: 0B51) is pleased to announce new drilling results from the 2025 drilling program at the Gaspé Copper Project, located in the Gaspé Peninsula of Eastern Québec. Results for eight new holes are reported below, located at the southern end of the deposit defined in the 2024 Mineral Resource Estimate (see attached map and November 14, 2024 news release).

Highlights (see Table 1 below):

• Drill hole 30-1075, located in the south-eastern portion of the 2024 MRE model, intersected 258.0 metres averaging 0.33% Cu and 2.95 g/t Ag (including 15.6 metres averaging 1.47% Cu and 8.5 g/t Ag), and a second intercept at depth, below the base of the 2024 MRE model, of 96 metres averaging 0.54% Cu and 3.34 g/t Ag, extending mineralization to a vertical depth of 529 metres.
• Drill hole 30-1076, located along the southern limit of the 2024 MRE model, intersected 208.4 metres averaging 0.40% Cu and 2.61 g/t Ag (including 12.0 metres averaging 1.91% Cu and 9.6 g/t Ag), followed by a second intercept of 70.8 metres averaging 0.25% Cu and 2.15 g/t Ag, and a third intercept at depth, below the base of the 2024 MRE model, of 48.9 metres averaging 0.34% Cu and 2.78 g/t Ag, extending mineralization to a vertical depth of 548 metres.
• Drill hole 30-1068, located in the south-eastern portion of the 2024 MRE model, intersected 189.0 metres averaging 0.30% Cu and 2.62 g/t Ag.
• Drill hole 30-1070, located near the eastern limit of the 2024 MRE model, intersected 160.5 metres averaging 0.16% Cu and 1.92 g/t Ag, followed by a second intercept of 122.8 metres averaging 0.62% Cu and 4.86 g/t Ag (including 25.6 metres averaging 2.19% Cu and 16.9 g/t Ag at the level of the C Zone skarn), followed by a third intercept at depth, below the base of the 2024 MRE model, of 29.7 metres averaging 1.92% Cu and 15.2 g/t Ag at the level of the E Zone skarn, extending mineralization to a vertical depth of 629 metres.

• Drill hole 30-1074, located in the south-central portion of the 2024 MRE model, intersected 118.5 metres averaging 0.26% Cu and 1.92 g/t Ag, and a second intercept of 167.2 metres averaging 0.22% Cu and 1.60 g/t Ag at depth below the base of the 2024 MRE model, extending mineralization to a vertical depth of 797 metres.

Table 1: Drill hole mineralized intervals, see attached map for drill hole locations.

Drill hole 30-1073 was drilled to the east of the 2024 MRE limit and did not intersect significant mineralization. Previously reported drill holes 30-1062 and 30-1066 were also collared to the southeast and to the east, respectively, of the 2024 MRE limit and these holes also failed to intersect significant mineralization, indicating that the deposit does not extend towards the east. The deposit remains open to the south and southwest.

All holes were drilled sub-vertically into the altered calcareous stratigraphy which dips 20 to 25 degrees to the north; true widths are estimated at 90-92% of reported widths. The L1 (C Zone) the L2 (E Zone) skarn/marble horizons were intersected in most holes, as well as intervening porcellanites (pale green to white potassic-altered hornfels) that host the bulk of the disseminated copper mineralization.

The November 2024 MRE was limited at depth to the base of the L1 skarn horizon (C Zone), and all mineralized intersections below this horizon represent potential depth extensions to the deposit, to be included in the next scheduled MRE update in Q1 2026.

Mineralization occurs as disseminations and veinlets of chalcopyrite and is mostly stratigraphically controlled in the area of Needle Mountain, Needle East and Copper Brook. As expected, no significant molybdenum mineralization was encountered in porcellanites in the latter areas, but high grades (up to 0.4% Mo) were locally obtained in both the C Zone and E Zone skarns. The bulk of the molybdenum mineralization occurs in veinlet stockworks further north at Copper Mountain, where true porphyry copper-style mineralization occurs, forming a distinct secondary mineralized zone that is characterized by widespread, continuous copper-molybdenum stockwork mineralization radiating from the central source of hydrothermal fluids, i.e. the Copper Mountain porphyry intrusion. At least five vein/stockwork mineralizing events have been recognized at Copper Mountain, which overprint earlier skarn/porcellanite-hosted mineralization throughout the Gaspé Copper system.

The 2022 to 2024 Osisko Metals drill programs were focused on defining open-pit resources within the Copper Mountain stockwork mineralization, leading to the May 2024 MRE (see May 6, 2024 press release). Extending the resource model south of Copper Mountain into the poorly-drilled primary skarn/porcellanite portion of the system subsequently led to a significantly increased resource, mostly in the Inferred category (see November 14, 2024 press release).

The current drill program is designed to convert the November 2024 MRE to Measured and Indicated categories, as well as test the extension of the system deeper into the stratigraphy and laterally to the south and southwest towards Needle East and Needle Mountain respectively.

Qualified Person

Mr. Bernard-Olivier Martel, P. Geo. is the Independent Qualified Person responsible for the technical data reported in this news release and he is a Professional Geologist registered in the Province of Quebec.

Quality Assurance / Quality Control

Mineralized intervals reported herein are calculated using an average 0.12% copper lower cut-off over contiguous 20-metre intersections (shorter intervals as the case may be at the upper and lower limits of reported intervals). Intervals of 20 metres or less are not reported unless indicating significantly higher grades.

Osisko Metals adheres to a strict QA/QC program for core handling, sampling, sample transportation and analyses, including insertion of blanks and standards in the sample stream. Drill core is drilled in HQ or NQ diameter and securely transported to its core processing facility on site, where it is logged, cut and sampled. Samples selected for assay are sealed and shipped to ALS Canada Ltd.’s preparation facility in Sudbury. Sample preparation details (code PREP-31DH) are available on the ALS Canada website. Pulps are analyzed at the ALS Canada Ltd. facility in North Vancouver, BC. All samples are analyzed by four acid digestion followed by both ICP-AES and ICP-MS for copper, molybdenum and silver.

About Osisko Metals

Osisko Metals Incorporated is a Canadian exploration and development company creating value in the critical metals sector, with a focus on copper and zinc. The Company acquired a 100% interest in the past-producing Gaspé Copper mine from Glencore Canada Corporation in July 2023. The Gaspé Copper mine is located near Murdochville in Québec‘s Gaspé Peninsula. The Company is currently focused on resource expansion of the Gaspé Copper system, with current Indicated Mineral Resources of 824 Mt averaging 0.34% CuEq and Inferred Mineral Resources of 670 Mt averaging 0.38% CuEq (in compliance with NI 43-101). For more information, see Osisko Metals’ November 14, 2024 news release entitled “Osisko Metals Announces Significant Increase in Mineral Resource at Gaspé Copper“. Gaspé Copper hosts the largest undeveloped copper resource in eastern North America, strategically located near existing infrastructure in the mining-friendly province of Québec.

In addition to the Gaspé Copper project, the Company is working with Appian Capital Advisory LLP through the Pine Point Mining Limited joint venture to advance one of Canada‘s largest past-producing zinc mining camps, the Pine Point project, located in the Northwest Territories. The current mineral resource estimate for the Pine Point project consists of Indicated Mineral Resources of 49.5 Mt averaging 5.52% ZnEq and Inferred Mineral Resources of 8.3 Mt averaging 5.64% ZnEq (in compliance with NI 43-101). For more information, see Osisko Metals‘ June 25, 2024 news release entitled “Osisko Metals releases Pine Point mineral resource estimate: 49.5 million tonnes of indicated resources at 5.52% ZnEq”. The Pine Point project is located on the south shore of Great Slave Lake, Northwest Territories, close to infrastructure, with paved road access, an electrical substation and 100 kilometers of viable haul roads.