O3 Mining - Marban Continues To Show Growth Potential

• Marban Engineering near pit expansion - adding value in Years 0 -10
• Marban Engineering resource growth - adding value in Years 10 plus
• Marban Regional - testing gold and Volcanogenic Massive Sulphide ("VMS") targets

"2023 will be an ambitious year for O3 Mining as we work towards completing the Marban Engineering Feasibility Study ("FS"), as well as engage in exploration activities to unveil Marban's growth potential over our 8,500 hectares property across the railroad from a world class deposit such as the Canadian Malartic Mine. Marban Engineering is a robust standalone project that can add more value to its NPV of C$463 million by discovering new ounces to extend the LOM. For every additional year of production (160,000oz Au), the impact on the fundamental value is between C$80 million to C$100 million.The more ounces added, the more value added to the project, therefore preparations are well underway for drill campaigns at Marban Engineering and Marban Regional, as well as compilation work from our summer soil sampling and channel sampling campaigns as we boost our exploration efforts.", said O3 Mining President and Chief Executive Officer, Mr. Jose Vizquerra.

• Norlartic and North resource and reserve update as part of the FS. A total of 8,800 metres has been drilled to convert a remaining 50,000 oz of gold from the inferred to the indicated category.
• 22.7 g/t Au over 3.4 metres starting at 76.9 metres in hole O3MA-22-368 including 84.8 g/t Au over 0.7 metres within the North pit
• 4.0 g/t Au over 11.7 metres starting at 334.7 metres in hole O3MA-22-347A including 24.8 g/t Au over 0.9 metres within the Norlartic pit
• Kierens: a few drill holes were completed to fill in a gap and connect the Kierens main pit with the Kierens satellite pit.

• Resource growth near surface
• Malartic H - has the potential to add a significant amount of near surface reserve to the mine as it is located four kilometres from the future plant and has been partly delineated by previous owners.
• Hygrade Fold - significant intercepts obtained earlier this year (Press Release, September 13, 2022) warrant follow up.
• North North Extension - low mag anomaly over the deposit extends for 1.5 kilometres to the NW from the North-North pit. Two drill holes tested the corridor this fall and successfully intersected the mineralized zone, but the assay results are pending. The corridor remains poorly tested.
• Norlartic Extension - 11,000 metres have been drilled in 2022 over recognized extensions of the Norlartic trend up to two kilometres towards the SE and adjacent to the north wall of the Marban pit. About half of the assay results from this campaign are still pending.
• Upper Camflo and Orion - Proximal to the historic Camflo mine, this target offers the possibility of generating near surface resource in the halo of the past producer
• Resource growth for underground potential.
• North - lateral and depth extensions of a 5.1 g/t Au over 5.1 metres intercept starting at 580.2 metres associated with a wide quartz vein (Press Release, March 9, 2021) remain untested and warrants follow up drilling.
• Marban Extension - the wide basalt unit hosting the Marban deposit is partially untested below 500 metres vertical before reaching the eastern property limit.
• Marban Footwall - a prospective basalt unit 200 metres south of the Marban mine basalt revealed to carry impressive high-grade values and remains partially open laterally and at depth.
• 1,045.0 g/t Au over 0.5 metres starting at 689.6 metres in hole O3MA-22-432

• Gold - High resolution drone mag survey completed Q1-2022, soil sampling campaign, compilation of historic results, mapping, and channel sampling of historic strippings
• Total soil sampling program: 4,411 samples, of which 3,496 assay results have been received
• Significant historic drill intercepts by NioGold Mining Corp. at Ludovick mineral occurrence along the Parfouru fault and within the Cadillac and Timiskaming sediments, contiguous to the Canadian Malartic mine property (Press Release, November 6, 2012, Sedar Issuer Profile: Niogold Mining)
• 23.40 g/t Au over 1.0m in hole CW-12-083 at a vertical depth of 115m.
• 9.55 g/t Au over 1. m in hole CW-12-090 at a vertical depth of 22m, 350 metres to the south of the Ludovick trend, within a lower grade interval of 0.58 g/t Au over 49.1m
• 9.06 g/t Au over 2.0m in hole CW-12-075 at a vertical depth of 115 m.
• Base Metals - Discovery of the Cu-Au-Ag-Zn exhalite - type and VTEM survey
• Heliborne VTEM survey (370km) covering a potential frontier VMS prospective sequence interpreted from the exhalite - type discovery and presence of felsic volcanics. The survey has been recently completed and interpretation of results are pending.

Table 1: Infill Drill Hole Intercepts (only intercepts above 20.0 g/t Au*m are reported, cut-off 0.3 g/t Au in or near pit shells)

Table 2: Near Surface Exploration Drill Hole Intercepts (only intercepts above 5.0 g/t Au*m are reported, cut-off 0.3 g/t Au and above 200m from surface)

Table 3: Deeper Exploration Drill Hole Intercepts (only intercepts above 5.0 g/t Au*m are reported, cut-off 0.3 g/t Au and below 200m from surface)

Figure 1: Marban Project Surface Map

Figure 2: Marban Exploration Outlook

Figure 3: Marban Project - Drilling Highlights

The scientific and technical content of this news release has been reviewed, prepared, and approved by Mr. Sébastien Vigneau. (OGQ #993), Principal Geologist, who is a "qualified person" as defined by National Instrument 43-101 - Standards of Disclosure for Mineral Projects ("NI 43-101").

O3 Mining Inc., an Osisko Group company, is a gold explorer and mine developer on the road to produce from its highly prospective gold camps in Québec, Canada. O3 Mining benefits from the support, previous mine-building success, and expertise of the Osisko team as it grows towards being a gold producer with several multi-million-ounce deposits in Québec.

O3 Mining is well-capitalized and owns a 100% interest in all its properties (66,000 hectares) in Québec. O3 Mining trades on the TSX Venture Exchange (TSXV: OIII) and OTC Markets (OTCQX: OIIIF). The Corporation is focused on delivering superior returns to its shareholders and long-term benefits to its stakeholders. Further information can be found on our website at https://o3mining.com

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this news release. No stock exchange, securities commission or other regulatory authority has approved or disapproved the information contained herein.

SOURCE O3 Mining Inc.



Contact
on O3 Mining, please contact: José Vizquerra Benavides, President, CEO and Director, Toll-Free: +1 (833) 979-3516, Telephone: +1 (873) 381-2014