­ Osisko Development Corporation announced sampling results from its ongoing underground exploration program at its 100%-owned Trixie test mine ("Trixie"), within the Company's wider Tintic Project ("Tintic"), located in the historic East Tintic Mining District in central Utah, U.S.A. 5,353 oz Au produced at an average grade of 31.3 g/t Au (0.91 oz/t Au since the Company's acquisition of Tintic ("Acquisition") on May 27, 2022. Current underground test mining activities at Trixie are directed by the exploration sampling and drilling results. Completed 7,315 m (24,000 ft.) of reverse circulation ("RC") drilling and 1,274 m (4,180 ft.) of diamond drilling since the date of the Acquisition, and four drill rigs currently in operation. Drill assay results are pending. The underground sampling results and drillhole information will form the basis of an initial mineral resource estimate, expected to be completed by the first quarter of 2023, to support near-term mine planning and production. 500 m (1,640 ft.) of Trixie portal and ramp construction (~30% complete) to date. Once fully complete, the decline will significantly improve access to the underground workings, expand and increase underground operations. High-grade gold results are present throughout the entire sampled area, and along exploration cross-cuts expanding the T4 structure up to 25 m (80 ft.) and parallel to T2. The mineralized structures remain open along strike and at depth and significant potential exists to expand the known mineralization. The Trixie test mine is one of several gold and base metal targets within the larger Tintic Project consisting of 17,000 acres of patented mining claims and mineral leases within the historic East Tintic Mining District of Central Utah, USA. The T2 and T4 structures at Trixie show multi-ounce gold grades associated with high sulphidation epithermal mineralization, structurally controlled and hosted within quartzites. High grade mineralized material from the T2 and T4 structures is currently being processed via vat leaching on site. The T2 structure is approximately 0.3 m to 2.4 m (1 to 8 ft.) wide and mineralization consists of native Au, and rare Au-Ag ­ rich telluride minerals with quartz. The T4 is a mineralized stockwork zone ranging from approximately 3 m to 25 m (10 to 80 ft.) and located in the hanging wall of the T2 and is comprised of Au-
Ag rich mineralization in host rock quartzite with quartz-barite-sulphosalt stockwork veining. Mineralization currently defined over 220 m (720 ft.) in strike and reports consistent multi-ounce gold grades along the entire strike length. As most structures at Trixie are steeply dipping to the east or west, current sampling procedures are designed to sample the structure. Chip samples are collected and do not exceed 1.0 m (3 ft.) in length. The
face is washed for safety, and for better identification of mineralization, alteration and structures. The hanging wall and footwall of the structures are marked up on the face and back, samples intervals are marked up and follow lithological contacts.