Opus One Gold hits 11.37 m at 4.92 g/t Au on Noyell

Highlights: Hole NO-26-21a returned 11.37 m grading 4.92 g/t gold. Hole NO-26-21a confirms that the high-grade gold mineralization in Zone 1 is continuous from surface down to the 700 m level (vertical). This high-grade shoot remains very strong and open at depth.

This interval is located on the same cross section but 200 m below the previously released hole NO-26-07 which returned  8.22 g/t gold over 8.5 m (true width: 7.16 m). Very few results have been received yet from the West Zone drill holes. NOT FOR DISTRIBUTION TO U.S NEWSWIRE SERVICES OR FOR DISSEMINATION IN THE UNITED STATES MONTREAL, June 17, 2026 (GLOBE NEWSWIRE) -- Opus One Gold Corp (TSX-V: OOR)  (the “ Company ” or “ Opus One ”) is pleased to release more assay results from the winter drilling program on its 100% owned Noyell property located in the northern portion of the Abitibi greenstone belt near the town of Matagami, Quebec, Canada.

Hole NO-26-21a, the deepest hole drilled so far on Zone 1 , returned 11.37 m grading 4.92 g/t gold (true width of 9.08 m). This hole confirms that the high-grade gold mineralization in the Zone 1 area is continuous from surface down to the 700 m level (vertical) .This high-grade shoot, along the eastern portion of Zone 1, remains very strong and open at depth. This interval is located on the same cross section but 200 m below the previously released hole NO-26-07 which returned 8.22 g/t gold over 8.5 m (true width: 7.16 m).

Zone 2 was not recognized in this hole. Hole NO-26-12 was drilled approximately 150 m to the west of NO-26-21a, in the central portion of Zone 1. Zone 1, intersected at 600 m vertical, returned 4.43 g/t gold over 1.88 m (true width: 1.68 m).

This is a better result than anticipated as this portion of Zone 1 was previously interpreted as potentially barren. Hole NO-26-15 was drilled approximately 350 m west of NO-26-21a at almost the same depth. This hole is part of a series of holes aimed at testing a potential vertical extension of Zone 1 in its western portion.

Assay results confirm that Zone 1 is weak along the western vector returning 0.84 g/t Au over 1 m (true width: 0.74 m) between 725 and 726 m. DRILL HOLE COORDINATES ASSAY RESULTS So far, no results have been released for the West Zone as very few results have been received to date for that sector of the property, where 5 holes were completed this winter. ZONE 1 DISCOVERY – LONGITUDINAL SECTION Metal Factor from 2025 interpretation.

To be modified to include 2026 drilling. Louis Morin, Opus One CEO commented: Our efforts and persistence are rewarded as more exciting results are coming from the Zone 1 gold bearing structure on Noyell. It is now confirmed that a high-grade gold vector is present from surface down to at least 700 m vertical as mineralization remains open at depth in that sector.

Continuity is good, grade is good, thickness is good as well. It looks very encouraging for future programs we will plan to verify potential continuity. Sample preparation, analysis and QAQC program All core recovered is NQ size.

All samples are described, labelled, cut (diamond saw) and bagged at Technominex’ facilities in Rouyn-Noranda. Samples are then shipped to AGAT certified Laboratory in Val D’or for preparation. Sample pulps are then shipped to various AGAT laboratories in Canada for analysis.

Samples are assayed for gold using Fire Assay - Trace Au, ICP-OES finish (50g charge). All samples equal or above 10 g/t Au are submitted to ore grade gravimetric finish. Multi element analysis are performed using Aqua Regia Digest - Metals Package, ICP-OES finish.

Opus One’s QAQC program consists of one control sample inserted, at Technominex’ facility, after 9 regular samples. Control samples consist of a certified blank and various gold grades certified material. OPUS ONE Resources Inc. Opus One Resources Inc. is a mining exploration company focused on discovering high quality gold and base metals deposits within strategically located properties in proven mining camps, close to existing mines in the Abitibi Greenstone Belt, north-western Quebec and north-eastern Ontario - one of the most prolific gold mining areas in the world.

Opus One holds assets in the Val-d'Or and Matagami mineral districts. An independent qualified person, Pierre O’Dowd P.Geo, has verified and approved the data disclosed, including sampling, analytical, and test data underlying the information or opinions contained in the written disclosure as required by section 3.1 and 3.2 of NI43-101. Forward-Looking Statements This news release contains statements that may constitute “forward-looking information” within the meaning of applicable Canadian securities legislation.

Forward-looking information may include, among others, statements regarding the future plans, costs, objectives or performance of Opus One, or the assumptions underlying any of the foregoing. In this news release, words such as “may”, “would”, “could”, “will”, “likely”, “believe”, “expect”, “anticipate”, “intend”, “plan”, “estimate” and similar words and the negative form thereof are used to identify forward-looking statements. Forward-looking statements should not be read as guarantees of future performance or results, and will not necessarily be accurate indications of whether, or the times at or by which, such future performance will be achieved.

No assurance can be given that any events anticipated by the forward-looking information will transpire or occur, including the anticipated exploration program on the project, the results of such exploration program, the development of the project and what benefits Opus One will derive from the project, the expected demand for lithium. Forward-looking information is based on information available at the time and/or management’s good-faith belief with respect to future events and are subject to known or unknown risks, uncertainties, assumptions, and other unpredictable factors, many of which are beyond Opus One’ control. These risks, uncertainties and assumptions include, but are not limited to, those described under “Financial Instruments” and “Risk and Uncertainties in Opus One’ Annual Report for the fiscal year ended August 31 st , 2025, a copy of which is available on SEDAR at www.sedar.com and could cause actual events or results to differ materially from those projected in any forward-looking statements.

Opus One does not intend, nor does Opus One undertake any obligation, to update or revise any forward-looking information contained in this news release to reflect subsequent information, events or circumstances or otherwise, except if required by applicable laws. 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 the release. For more information, please contact: Louis Morin Chief Executive Officer & Director Tel.: (514) 591-3988 Michael W. Kinley, CPA, CA President, Chief Financial Officer & Director Tel: (902) 402-0388 info@OpusOneGold.com Visit Opus One’s website: www.OpusOneGold.com OPUS ONE’S NOYELL PROPERTY LOCATION MAPS PROPERTY GEOLOGY AND GOLD TARGETS Infographics accompanying this announcement are available at https://www.globenewswire.com/NewsRoom/AttachmentNg/ee0e50c2-fc0c-42d8-9ea8-e29069366653 https://www.globenewswire.com/NewsRoom/AttachmentNg/0ac20d17-55ba-4a46-8949-c410280e7c75 https://www.globenewswire.com/NewsRoom/AttachmentNg/438b9581-454f-42d0-ab65-20b3a5e53cea https://www.globenewswire.com/NewsRoom/AttachmentNg/74c82964-1ca5-4191-9af9-7f5dc10ea1bd https://www.globenewswire.com/NewsRoom/AttachmentNg/44b1cbd6-87e7-4fb1-91a4-437be76c8a87 https://www.globenewswire.com/NewsRoom/AttachmentNg/ad81f08d-e3cf-4e95-a6ed-8e3345d1237f Globe Newswire June 17, 2026 - 6:00 AM PDT News by QuoteMedia www.quotemedia.com