O3 Mining Inc. Intersects 6.4 G/T Au Over 7.5 Metres At Alpha

Current drilling on the Alpha property continues to show the continuity of the Bulldog zone at depth. New analytical results from the Bulldog zone include 6.4 g/t Au over 7.5 m in hole O3AL-20-290B. This drill hole intersected the Bulldog zone at a vertical depth of 500 m and approximately 200 m east of the previously reported drill hole O3AL-20-287 (See Press Release February 28, 2020). The Bulldog zone can now be traced over 500 metres vertically and between 100 and 200 metres laterally. The zone remains open at depth. Mineralization at the Bulldog zone is associated with sheared, carbonatized, and sericitized wackes and intermediate to felsic dykes containing 1–3% fine disseminated pyrite and 10% dismembered quartz veins. Three drill rigs continue to follow up on significant intercepts on the Alpha property, including one at Bulldog and two at Epsilon.

Table 1: Drill Hole Intercepts (only intercepts above 5 g/t Au * m are reported)

NOTE: True width determination is currently unknown but is estimated at 65-80% of the reported core length interval for the zones. Results from holes 286B and 299C are partial, Bulldog zone assays results pending.

Table 2: Drill Hole Details

O3AL-20-286B intersected 2.9 g/t Au over 5.1 m associated to the Bulldog zone. The mineralization is related to alternating, sheared and carbonatized wacke, intermediate sericitized dykes and albitized felsic dykes containing 1% disseminated pyrite.

O3AL-20-290B intersected 1.9 g/t Au over 32.8 m associated to the Bulldog zone. The mineralization is related to altered wacke crosscut by an intermediate dyke and three albitized felsic dykes. The intermediate intrusion is strongly sheared and sericitized and contains 5% dismembered quartz veins with 2 to 5% pyrite and returned 6.4 g/t Au over 7.5 m. The three felsic dykes have anomalous gold values while the wacke surrounding those intrusions returned 3.2 g/t Au over 2.5 m and 5.7 g/t Au over 1.0 m.

O3AL-20-299C intersected 14.9 g/t Au over 0.5 m associated with a currently unassigned zone. Mineralization is within a granodiorite dyke containing up to 1% coarse grained pyrite.

O3AL-20-300 intersected 2.1 g/t Au over 1.8 m associated with the Bulldog zone. The mineralization consists of 1-2% fine to medium grained disseminated pyrite with traces of chalcopyrite and pyrrhotite within a moderately sericitized and carbonated wacke.

Figure 1: Alpha Property Map is available at https://www.globenewswire.com/NewsRoom/AttachmentNg/93f80478-0b94-45ff-953c-a3889e2889c6

Figure 2: Alpha Property Drilling is available at https://www.globenewswire.com/NewsRoom/AttachmentNg/0658e10f-c833-4cdd-9187-9d522a13b086

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

Quality Control and Reporting Protocols
True width determination is currently unknown but is estimated at 65-80% of the reported core length interval for the zones. Assays are uncut except where indicated. Intercepts occur within geological confines of major zones but have not been correlated to individual vein domains at this time. Half-core samples are shipped to Agat laboratory in Val D’Or, Quebec and Mississauga, Ontario for assaying. The core is crushed to 75% passing -2 mm (10 mesh), a 250 g split of this material is pulverized to 85% passing 75 microns (200 mesh) and 50 g is analyzed by Fire Assay (FA) with an Atomic Absorption Spectrometry (AAS) finish. Samples assaying >10.0 g/t Au are re-analyzed with a gravimetric finish using a 50 g charge. Commercial certified standard material and blanks are systematically inserted by O3 Mining’s geologists into the sample chain after every 18 core samples as part of the QA/QC program. Third-party assays are submitted to other designated laboratories for 5% of all samples. Drill program design, Quality Assurance/Quality Control ("QA/QC") and interpretation of results are performed by qualified persons employing a QA/QC program consistent with NI 43-101 and industry best practices.

About O3 Mining Inc.
O3 Mining, an Osisko group of companies, is an emerging consolidator of exploration properties in prospective gold camps in Canada – focused on projects in Quebec and Ontario - with a goal of becoming a multi-million ounce, high-growth company. The Corporation's goal is to become one of the premier gold exploration companies in Canada.

O3 Mining is well-capitalized and holds a 100% interest in a number of properties in Quebec (435,000 hectares) and Ontario (25,000 hectares). O3 Mining controls 61,000 hectares in Val D'Or and over 50 kilometres of strike length of the Cadillac-Larder Lake Faut. O3 Mining also has a portfolio of assets in the James Bay and Chibougamau regions of Quebec and in the Hemlo district in Ontario.

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.

For further information on O3 Mining, please contact:
José Vizquerra Benavides, President, CEO and Director
Telephone: (416) 363-8653