Orosur Mining Inc Announces Colombia update

• Assays from second hole of current drill program (PEP013) received.

• Composite intersection of 77.3m @ 7.68g/t Au from surface.

• Assays from third hole (PEP014) expected shortly.

• Drilling of fourth hole (PEP015) has been completed and assays dispatched to the lab for analysis.

• Preparation of platform for PEP016 under way.

LONDON, December 9, 2024 - Orosur Mining Inc. ("Orosur" or the "Company") (TSXV:OMI)(AIM:OMI), is pleased to announce an update on the progress of exploration activities at the Company's flagship Anzá Project ("Project") in Colombia.

ANZÁ Project
The Anzá Project is now 100% owned by the Company following recent completion of a Share Purchase Agreement (SPA), announced 28^th November 2024, whereby the Company purchased all of the shares of its previous JV partner, Minera Monte Aguila (MMA).

During the JV, the Project comprised several granted exploration licences and applications totalling roughly 176km2, covering a large strike length of major structures on the mid-Cauca belt, Colombia's primary gold region (Figure 1).

Post the acquisition of MMA, the area of the Project has increased substantially to roughly 400km2 due to the acquisition of a number of additional applications that were owned by MMA. The full extent of these new applications is currently being assessed and will be detailed in a later announcement.

The Project is located 50km west of Medellin and is easily accessible by all-weather roads and boasts excellent infrastructure including water, power, communications as well as a large exploration camp.

Figure 1 - Anzá Project (pre-MMA transaction)

Pepas
The Pepas Prospect is in the northern extent of the Anzá Project (pre-acquisition) over 10km north of the central base at APTA (Figure 2).

Figure 2. Anzá Project - prospects

Field work commenced at Pepas in late 2021 as the gradual abatement of Covid allowed field crews to move outside a covid bubble that had constrained their movements during the pandemic to the core APTA deposit that had up to that point been the target of most historical exploration work.

The Company mobilised a drill rig to site in mid-November with a view to a small program of approximately 800m with the dual objectives of assessing the continuity of gold mineralisation identified in previous drilling and gaining of greater understanding of the orientation of mineralisation and its lithostructural controls.

The first hole of this new program, PEP012, was collared adjacent to mapped artisanal workings and directed back toward the first of the previous JV holes (PEP001), as a scissor hole, a reasonably standard strategy in instances of uncertain geological orientation. Assay results for PEP012 were announced on 2^nd December 2024, and returned an excellent intersection of 66.75m @ 5.64g/t Au from surface.

PEP013 was collared from the same pad as PEP012 but rotated 51 degrees to the east to be orientated to be more orthogonal to what is currently interpreted as the strike of the mineralisation and controlling structures.

Figure 3. Plan of holes

As with PEP012, PEP013 entered highly mineralised tuffs almost immediately, of similar nature to that seen in PEP001 and PEP012, before intersecting a basement fault at 79m, very close to the predicted depth. The hole was terminated at 85m.

Figure 4. Section, PEP013

The entire length of PEP013 above the fault, was mineralised with a composite intersection of 77.3m @ 7.68g/t Au being calculated, from surface.

Table 1. Drill Intercepts

Discussion and ongoing drilling
Hole PEP012 was designed largely as a confirmatory hole, to verify previous drilling undertaken by the Company's former JV partner in 2022, and to gain better understanding of the nature and orientation of the recorded mineralisation.

Hole PEP013 was drilled in a direction that was deemed to be more orthogonal to what is currently interpreted as the trend of the mineralisation, roughly SE to NW. Intersection of the basement fault at close to the predicted depth, lends weight to this interpretation.

Later holes PEP014 and PEP015 are positioned on the same dip and azimuth as PEP013 but shifted to the NW (Figure 3) by various separations, to a large extent driven by access for drill pad creation. The objective of these holes is to further define mineralisation, and to provide sufficient pierce points into the basement fault to allow more reliable interpretation of the mineralisation trend.

Hole PEP016 is a deeper hole located some distance to the SW that is planned to test downdip extensions and to begin the process of assessing the wider extent of the Pepas mineralisation.

PEP014 has been completed and assays should be available shortly. PEP015 has been completed and assays have been dispatched to the lab for analysis, whilst preparation of the platform for the drilling of PEP016 is under way.

Orosur CEO Brad George commented:
"Results from PEP013 are little short of exceptional in terms of thickness and grade, especially from surface. But of equal importance is the information this hole has provided in relation to the form and orientation of the Pepas mineralisation. A few more like this and perhaps we can then start to step out and define its size".

For further information, visitwww.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 & Joint Broker
Jeff Keating / Caroline Rowe
Tel: +44 (0) 20 3470 0470

Turner Pope Investments (TPI) Ltd - Joint Broker

Andy Thacker/James Pope
Tel: +44 (0)20 3657 0050

Flagstaff Communications and Investor 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.

Drill Hole Details - Pepas prospect 2022/2024 Programme*

* Coordinates WGS84, UTM Zone 18
** Preliminary coordinates with handheld GPS. To be later verified by survey

About Orosur Mining Inc.

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

About the Anzá Project
Anzá is a gold exploration project, comprising three exploration licences, four exploration licence applications, and several small exploitation permits, totalling 176km2 in the prolific Mid-Cauca belt of Colombia. Post the acquisition of Minera Monte Aguila S.A.S, the area of the Project has increased substantially to approximately 400km2 due to the acquisition of a number of additional applications that were owned by Minera Monte Aguila S.A.S.

The Anzá Project is currently wholly owned by Orosur via its subsidiaries, Minera Anzá S.A. and Minera Monte Aquila S.A.S.

The project is located 50km west of Medellin and is easily accessible by all-weather roads and boasts excellent infrastructure including water, power, communications and large exploration camp.

Qualified Persons Statement
The information in this news release was compiled, reviewed and verified 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.

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, 2024. 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.

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SOURCE: Orosur Mining Inc