Orosur Mining Inc - Results for First Quarter ended August 31, 2025

 Results for First Quarter ended August 31, 2025

London, 24th, October 2025. Orosur Mining Inc. ("Orosur" or "the Company") (TSX-V: OMI) (AIM: OMI) announces its audited results for the first quarter ended August 31, 2025. All dollar figures are stated in thousands of US$ unless otherwise noted. The unaudited condensed interim financial statements of the Company for the quarter ended August 31, 2025 and the related management's discussion and analysis ("MD&A") have been filed and are available for review on the SEDAR+ website at www.sedarplus.ca. The financial statements and the MD&A are also available on the Company's website at www.orosur.ca.

A link to the PDF version of the financial statements is available here: http://www.rns-pdf.londonstockexchange.com/rns/6451E_2-2025-10-23.pdf

A link to the PDF version of the MD&A is available here: http://www.rns-pdf.londonstockexchange.com/rns/6451E_1-2025-10-23.pdf

HIGHLIGHTS

Highlights for the three months ended August 31, 2025 include:

Operational

·      In Colombia, on July 14, 2025, the Company announced that it had taken the formal decision to begin a work program that, if successful, would allow a Mineral Resource Estimate to be calculated at its Pepas gold prospect, within the Anzá gold project area in Colombia. The decision was taken on the basis of external conceptual studies that suggest the location and physical characteristics of the gold mineralisation so far defined at Pepas, in the context of record high gold prices, may offer potential nearer term production opportunities. The in-fill drilling program continued throughout the quarter and post the period end and may be followed by a Mineral Resource Estimate and an evaluation of the economics for production at Pepas. Thereafter the Company will return to wider exploration drilling, including at APTA.

Earlier stage exploration continues at the El Cedro prospect. The El Cedro prospect is a large gold porphyry system, located toward the south of the Anzá project, on the same granted exploration licence as the Pepas and APTA deposits. The Company recommenced a large ridge and spur soil sampling program at El Cedro that had been previously suspended due to seasonal rain and access issues.  This program has continued beyond the period end and is now 90% complete.

·      In Argentina, earlier this year the Company announced the successful completion of the first phase of the two-phase exploration joint venture over the El Pantano gold project in Santa Cruz province, Argentina ("Project" or "El Pantano"). This milestone marked a significant step forward in the Company's strategic development of the Project. Having invested US$1m over three years, the Company has now earned a direct 51% interest in the Argentine company, Deseado Dorado S.A.S ("Deseado"), that owns the exploration licences that make up the Project. The Company has now moved into the second phase of the JV, that will see it move to 100% ownership of Deseado upon investment of an additional US$2m over two years. Upon such an outcome, the original vendors would then retain a residual 2% NSR royalty, 1% of which the Company could repurchase at its election for US$1m. A geophysical campaign was completed during the quarter with the objective of further refining targets at the Project where drilling is expected to commence imminently with a 3,000 metre program of diamond drilling.

·      In Nigeria, given the continued weakness in the price of lithium and in view of the Company's need to prioritise the use of its capital and human resources, a decision has been taken to withdraw from the project which should happen over the next few weeks. The investment in Nigeria was fully impaired in the Company's financial statements as at May 31, 2025.

Financial

·      On August 31, 2025, the Company had a cash balance of $3,906 (May 31, 2025 $4,877). As at the date of this MD&A and including the funds raised in the private placement (detailed below), the Company had a cash balance of $17.2 million.

·      Post period end, on September 18, 2025 the Company announced an upsized brokered private placement (the "Placing") to raise gross proceeds of up to CAD$ 20 million through the issue of up to 58,823,530 common shares at a price of CAD$0.34 per common share. The Placing, which was over- subscribed, was completed on October 2 2025 and raised CAD$ 20 million. No warrants were issued in connection with the Placing.

Outlook and Strategy

The Company will focus its investment in Colombia and Argentina whilst also looking for new opportunities in South America.

In Colombia, within the Anza Project, the Company is looking to complete its in-fill drilling program at Pepas which would allow Maiden Resource Estimate to be completed at Pepas. Thereafter the Company will continue to investigate the possibility of a resource estimate at its APTA prospect whilst it refines its geological models around Pepas to identify possible target areas. At El Cedro, geological mapping and sampling is nearing completion. Historical geophysics is being reprocessed and, if warranted, new geophysical data will be acquired.

In Argentina, the Company will shortly commence a 3,000 metre drilling program at the El Pantano project.

For further information, visit www.orosur.ca, follow on X @orosurm or please contact:

Orosur Mining Inc

Louis Castro, Chairman,

Brad George, CEO

info@orosur.ca

Tel: +1 (778) 373-0100

SP Angel Corporate Finance LLP - Nomad & Broker

Jeff Keating / Jen Clarke / Devik Mehta

Tel: +44 (0) 20 3 470 0470

Turner Pope Investments (TPI) Ltd - Joint Broker

Andy Thacker/James Pope

Tel: +44 (0)20 3657 0050

Flagstaff Communications

Tim Thompson

Mark Edwards

Fergus Mellon

orosur@flagstaffcomms.com              Tel: +44 (0)207 129 1474

The information contained within this announcement is deemed by the Company to constitute inside information as stipulated under the Market Abuse Regulations (EU) No. 596/2014 ('MAR') which has been incorporated into UK law by the European Union (Withdrawal) Act 2018. Upon the publication of this announcement via Regulatory Information Service ('RIS'), this inside information is now considered to be in the public domain.

Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

About Orosur Mining Inc.

Orosur Mining Inc. (TSXV: OMI; AIM: OMI) is a minerals explorer and developer currently operating in Colombia and Argentina.

Qualified Persons Statement

The information in this news release was compiled, reviewed, verified and approved by Mr. Brad George, BSc Hons (Geology and Geophysics), MBA, Member of the Australian Institute of Geoscientists (MAIG), CEO of Orosur Mining Inc. and a qualified person as defined by National Instrument 43-101.

Orosur Mining Inc. staff follow standard operating and quality assurance procedures to ensure that sampling techniques and sample results meet international reporting standards. Drill core is split in half over widths that vary between 0.3m and 2m, depending upon the geological domain. One half is kept on site in the Minera Anzá core storage facility, with the other sent for assay.

Industry standard QAQC protocols are put in place with approximately 10% of total submitted samples being blanks, repeats or Certified Reference Materials (CRMs). Samples for holes PEP-001 to PEP-011 were sent to the Medellin preparation facility of ALS Colombia Ltd, and then to the ISO 9001 certified ALS Chemex laboratory in Lima, Peru.

Samples from PEP-012 onwards are sent to Medellin laboratory of Actlabs for preparation and assay.

30 gram nominal weight samples are then subject to fire assay and AAS analysis for gold with gravimetric re-finish for overlimit assays of >5 g/t.  ICP-MS Ultra-Trace level multi-element four-acid digest analyses may also undertaken for such elements as silver, copper, lead and zinc, etc.

Gold intersections are reported using a lower cut-off of 0.3g/t Au over 3m. Intersections are quoted as downhole thicknesses.  True thicknesses are unknown.

Forward Looking Statements

All statements, other than statements of historical fact, contained in this news release constitute "forward looking statements" within the meaning of applicable securities laws, including but not limited to the "safe harbour" provisions of the United States Private Securities Litigation Reform Act of 1995 and are based on expectations estimates and projections as of the date of this news release.

Forward-looking statements include, without limitation, the continuing focus on the Pepas prospect, the exploration plans in Colombia and the funding of those plans, and other events or conditions that may occur in the future. There can be no assurance that such statements will prove to be accurate. Actual results and future events could differ materially from those anticipated in such forward-looking statements. Such statements are subject to significant risks and uncertainties including, but not limited to, those described in the Section "Risks Factors" of the Company's MD&A for the year ended May 31, 2025. The Company's continuance as a going concern is dependent upon its ability to obtain adequate financing. This material uncertainty may cast significant doubt upon the Company's ability to realize its assets and discharge its liabilities in the normal course of business and accordingly the appropriateness of the use of accounting principles applicable to a going concern. The Company disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information, future events and such forward-looking statements, except to the extent required by applicable law.