Orosur Mining Inc. - Full Year 2025 Results

London, 29th, September 2025. Orosur Mining Inc. ("Orosur" or "the Company") (TSX-V: OMI) (AIM: OMI) announces its audited results for the fiscal year ended May 31, 2025. All dollar figures are stated in thousands of US$ unless otherwise noted. The audited financial statements of the Company for the year ended May 31, 2025; the related management's discussion and analysis ("MD&A"); and Forms 52-109FV1 will be filed today and be 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/1016B_1-2025-9-27.pdf

A link to the PDF version of the MD&A is available here:

http://www.rns-pdf.londonstockexchange.com/rns/1016B_2-2025-9-27.pdf

HIGHLIGHTS

Highlights for the year ended May 31, 2025 include:

Operational

In Colombia, on November 27, 2024, the Company completed the acquisition of Minera Monte Aguila S.A.S. ("Monte Aguila") as a result of which the Company now has 100% ownership of the Company's flagship Anzá Gold Project. The Company also re-took operatorship of the Anza Gold Project, commencing a drilling program at the Pepas prospect in late November 2024 which is still continuing and has produced some exceptional results, all of which have been announced by the Company since that date.

While exploration continues across several prospects at Anzá, the Company feels that the nature of the gold mineralisation thus far defined at Pepas, could, if proven, underpin a range of development options. Consequently, the Company has begun examining the potential for nearer term production at Pepas, initially through an in-fill drilling programme, 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.

In the meantime, earlier stage exploration continues at the El Cedro prospect, which lies to the south of the same integrated licence that hosts Pepas, Pepas North and APTA and is roughly 4km south of the APTA base camp.

Work on El Cedro began some years ago before Orosur's tenure, when Anglo American undertook reconnaissance mapping and sampling, identifying a highly prospective gold/copper porphyry system. Large soil samples have been taken at roughly 25m intervals, along ridges and spurs for ease of access and to ensure soils were residual. Samples were sent to both Medellin and Canada for assay. Early assay results have been returned and show highly anomalous results over large areas along the eastern flank, with substantial areas of over 0.3 g/t Au in soils, and some samples in excess of 1 g/t Au and 0.5% Cu. A wider area is being sampled to more accurately define the background levels, however these early results are considered by Orosur to be highly encouraging.

In Argentina, on February 17, 2025, the Company announced the successful completion of the first phase of the two-phase exploration joint venture over the El Pantano Project in Santa Cruz province, Argentina. This milestone marks 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 can now move to the second phase of the JV, that could 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.

Post period end, a geo-physical campaign comprising IP was shot over one of the more prospective parts of the Project area. The data was then interpreted to provide the preferred locations for drilling which will take place later this year subject to finance.

In Nigeria, the Company will consider how to best deal with the project given the continuing subdued lithium market.

In Uruguay, in accordance with the Creditors' Agreement, the Company's wholly owned subsidiary, Loryser has sold all of its assets. It has paid for the settlements with all of its former employees; it has finalised the reclamation and remediation works on the tailings dam and has successfully concluded a one-year post-closure control phase. It has then distributed all remaining proceeds, via a Court approved paying agent, to Loryser's trade creditors and paid any remaining unclaimed amounts into the Court, in accordance with the Creditors' Agreement. Given that Loryser has fulfilled all of its obligations under the Creditors' Agreement, the Company has extinguished the carrying amounts due to commercial suppliers and borrowings on its Statement of Financial Position.

Financial and Corporate

The audited consolidated financial statements have been prepared on a going concern basis under the historical cost method except for items measured at fair value, and assets and liabilities related to discontinued operations, which are measured at the lower of cost or recoverable amount. This accounting treatment has been applied to the activities in Uruguay and Chile.

At the Company's AGM, held on December 12, 2024, all resolutions put to shareholders were duly passed.

On September 30, 2024, the Company announced that it had raised the sum of £835,000 ($1,096) (before expenses) through a placing of 30,035,971 new common shares of no par value ("Placing Share") at a price of 2.78 pence per Placing Share, together with a grant of one unlisted warrant to purchase one additional common share exercisable at US$0.0494 (approximately 3.697p) for every two Placing Shares subscribed for. As part of the raise, the Company also issued 3,003,597 brokers warrants ("Broker Warrants"). Each Broker Warrant can be exercised for one common share at an exercisable price of $0.03715 for a period of 5 years from the date of issuance.

On December 19, 2024, the Company announced that it had raised the sum of £1,250,000 ($1,566) (before expenses) through a placing of 18,939,394 new common shares of no par value ("Placing Share") at a price of 6.6 pence per Placing Share. As part of the raise, the Company also issued 1,893,939 brokers warrants ("Broker Warrants"). Each Broker Warrant can be exercised for one common share at an exercisable price of $0.0832 for a period of 5 years from the date of issuance. 

On March 27, 2025, the Company announced the closing of an oversubscribed private placement (the "Private Placement") which raised aggregate gross proceeds of C$6,000,000 ($4,193), including the full exercise of the broker's option for gross proceeds of C$1,000,000 ($699). Under the Private Placement, the Company sold an aggregate of 35,294,117 units of the Company (the "Units") at a price of C$0.17 per Unit. Each Unit consisted of one common share of the Company (each, a "Unit Share") and one half of one common share purchase warrant (each whole warrant, a "Warrant"). Each whole Warrant entitles the holder to purchase one common share of the Company (each, a "Warrant Share") at a price of C$0.25 at any time on or before March 27, 2027. As part of the raise, the Company also issued 1,893,705 brokers warrants ("Broker Warrants"). Each Broker Warrant can be exercised for one common share at an exercisable price of CAD$0.17 for a period of 2 years from the date of issuance.

On September 18, 2025, subsequent to the year end, the Company announced an upsized brokered private placement (the "Placing") to raise gross proceeds of up to C$20,000,000 ($14,388) including the full exercise of the broker's option for gross proceeds of C$2,000,000 ($1.438), through the issue of up to 58,823,530 common shares at a price of C$0.34 per common share. No warrants have been issued in connection with the Placing. The Placing is expected to close on or about October 2, 2025.

On May 31, 2025, the Company had a cash balance of $4,877 (May 31, 2024 - $1,328). As at the date of this MD&A the Company had a cash balance of $4,188.

Outlook and Strategy

Given the recent acquisition by the Company of MMA, through which the Company has retaken 100% of its flagship project at Anza; the spectacular results at Pepas; and the encouraging results at the Company's El Pantano Project in Argentina, the Company will focus its investment principally in these areas.

In Colombia, within the Anza Project, the Company is aiming for a Mineral Resource Estimate by December this year at Pepas, to be followed by an economic assessment of potential near term production at Pepas. Thereafter the Company will return to wider exploration drilling, including at APTA. Further exploration will continue around the El Cedro prospect which could host a porphyry system with a view to potential drilling next year.

In Argentina, the Company aims to carry out a drilling program, later this year, to follow up on targets established by all of the Company's previous exploration work at its 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

[email protected]

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

[email protected]              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, Argentina and Nigeria.

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, to reach profitable levels of operations and to reach a satisfactory closure of the Creditor´s Agreement in Uruguay. These material uncertainties 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.