Orosur Mining Inc Announces Colombia update

• Assays from five additional holes - MAP-101 to 105.
• Results generally reflect lower levels of gold anomalism but high-grade zinc and copper evident at depth, beyond the capacity of the existing rig fleet.
• Focus shifted to northern prospects - two rigs drilling at Pepas and one at Pupino with another rig being mobilised.
• First assay results from Pepas expected in July.

For the full PDF version of the announcement with Figures 1-5 included, please refer to: http://www.rns-pdf.londonstockexchange.com/rns/2088Q_1-2022-6-26.pdf

LONDON, June 27, 2022 - Orosur Mining Inc. ("Orosur" or the "Company") (TSX-V:OMI; AIM:OMI), is pleased to announce an update on the progress of exploration activities at the Company's flagship Anzá project in Colombia.

Exploration work at Anzá is under the operational control of the Company's Joint Venture partner, Minera Monte Águila SAS ("Monte Águila"). Monte Águila is a 50/50 joint venture between Newmont Corporation ("Newmont") (NYSE:NEM, TSX:NEM) and Agnico Eagle Mines Ltd. ("Agnico") (NYSE:AEM, TSX:AEM) and is the vehicle by which these two companies jointly exercise their rights and obligations with respect to the Exploration Agreement with Venture Option ("Exploration Agreement") over the Anzá Project.

Assay results from the final five holes drilled at the APTA prospect have been received. In general, the results reflect lower levels of gold anomalism compared to previously drilled holes, but show some high-grade base metal results, similar to intersections from previous drilling, adding support to the theory of hybrid volcanogenic massive sulphide (VMS)/intermediate-sulfidation epithermal system.

While few significant gold intercepts were recorded, this was not wholly unexpected as these holes were drilled to better define the geological and structural context of the APTA environment whilst the Company awaited mapping, sampling, geophysics and land access to be finalised on the northern prospects.

These results would suggest that while APTA remains a highly prospective target, with multiple thick and high-grade intersections having been previously recorded, it is also complex and has substantial depth extent that is beyond the capacity of the current drill rig fleet to test.

As previously announced on April 25^th, 2022, drilling ceased at APTA in late March with the remaining Colombian rig being mobilised to the Pepas prospect at the far northern extent of the project area. The focus of the scout drilling program in the NE of the project area is to test several anomalous targets identified through surface mapping and sampling, geophysics, and geochemistry - it is planned to have four rigs operating in this area, with two each at Pepas and Pupino.

Assay Results

Assay results from the final five holes drilled at APTA have been received from the ALS laboratory in Lima, Peru (MAP-101 to 105). Key intersections from these holes are noted below:

MAP-102 4.85m @ 0.51g/t Au, 1.24g/t 0.16% Zn

MAP-103 0.75m @ 3.30g/t Au, 0.86g/t Ag, 0.14% Zn

0.95m @ 4.90g/t Au, 3.49g/t Ag, 3.39% Zn

MAP-104 5.35m @ 2.62g/t Au, 2.61g/t Ag, 1.04% Zn

0.50m @ 22.80g/t Au, 13.95g/t Ag, 0.52%Zn

MAP-105 2.50m @ 3.30g/t Au, 1.61g/t Ag, 0.06% Zn

9.25m @ 1.77g/t Au, 4.63 g/t Ag, 5.33% Zn

9.70m @ 0.17g/t Au, 2.59 g/t Ag, 13.88% Zn, 0.91% Cu

Full results from these holes are noted below.

Table 1. Drill Intercepts.

Figure 1. Plan of last five holes

Figure 2. Plan, all holes since 2020

MAP-101

MAP-101 was drilled well to the north of all previous drilling and angled away to a NW azimuth. The primary objective of the hole was to intersect and thus confirm the location of the northward continuation of the Aragon fault.

The hole was successful in these objectives, but no substantial mineralisation was intersected.

MAP-102

MAP-102 was drilled to test the northern extension of higher-grade mineralisation previously intersected in hole MAP-089. While substantial widths of mineralisation were intersected, these were of lower grade, and somewhat similar to the nearby hole MAP-097.

Figure 3. Section MAP-102

MAP-104

MAP-104 was drilled into a gap between the previously defined north and south sections of the APTA zone. This is a zone where the primary structures change direction and thus it was necessary to better define this section.

Some narrow high-grade gold and base metal veins were intersected.

Figure 4. Section MAP-104

MAP-103,105

MAP-103 and 105 were drilled to test the continuity of mineralisation previously intersected in MAP-098, but also to push downward to test stratigraphy to the limit of the available rigs. Both holes were drilled from the west, and so designed more as stratigraphic holes.

Reasonable intersections of gold mineralisation were intersected, however of most interest was the intersection in MAP-105 of a likely VMS system at depth with high grade zinc and copper mineralisation, including 5.95m @ 18% Zn and 1.4% Cu from 478m.

Figure 5. Section MAP-103 & MAP-105

Other Drilling

As previously announced on April 25^th, 2022, drilling activities ceased at APTA in March, with the remaining rig mobilised to the northern Pepas prospect.

Extensive programs of mapping, sampling and geophysics had been undertaken along the northern extent of the Aragon fault and associated structures over previous months, with highly anomalous geochemical and geophysical responses being recorded. Access to the area however was challenging due to terrain issues and substantial logistical infrastructure and support was required to be developed before rigs could be mobilised.

Drilling commenced at Pepas with one rig in April, with a second rig mobilised to Pepas in recent weeks. The Company is also informed that a third rig has commenced drilling at Pupino, with a fourth in the process of being mobilised to commence at Pupino in the near term.

Core from the first hole at Pupino have been submitted to the laboratory for assay and results are expected soon.

Orosur CEO Brad George commented:

"This last batch of holes were largely focused on resolving stratigraphic and structural issues at APTA, while waiting for permitting and access to be developed at the highly prospective northern prospects of Pepas and Pupino. APTA has been the focus of attention for Waymar, Orosur and Monte Águila since 2012 with the remaining 20km of strike of the Aragon Fault tantalisingly out of reach. APTA proved the region is fertile, and field mapping in the north suggested this could continue, but it was only in April that we were finally able to move rigs onto these targets. We await with some anticipation the results of recent drilling at Pepas and Pupino and look forward to updating shareholders shortly."

For further information visit www.orosur.ca, follow on twitter @orosurm or 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 3 470 0470

Turner Pope Investments (TPI) Ltd - Joint Broker

Andy Thacker

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 is now considered to be in the public domain.

Drill Hole Details - 2020/2021 Programme*

* Coordinates WGS84, UTM Zone 18

About Orosur Mining Inc.

Orosur Mining Inc. (TSX-V: OMI; AIM: OMI) is a minerals explorer and developer focused on identifying and advancing projects in South America. The Company currently operates in Colombia, Brazil, Argentina and Uruguay.

About the Anzá Project

Anzá is a gold exploration project, comprising three exploration licences, four exploration licence applications, and several small exploitation permits, totalling 207.5km² in the prolific Mid-Cauca belt of Colombia.

The Anzá Project is currently wholly owned by Orosur via its subsidiary, Minera Anzá S.A.

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.

The Anza? Project is subject to an Exploration Agreement with Venture Option dated September 7^th, 2018, as announced on September 10^th, 2018, between Orosur's 100% subsidiary Minera Anza? S.A ("Minera Anza?") and Minera Monte A?guila SAS ("Monte A?guila"), a 50/50 joint venture between Newmont Corp. ("Newmont") (NYSE:NEM, TSX:NGT), and Agnico Eagle Mines Ltd. ("Agnico") (NYSE:AEM, TSX:AEM).

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 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 20% of total submitted samples being blanks, repeats or Certified Reference Materials (CRMs).

Samples are sent to the Medellin preparation facility of ALS Colombia Ltd, and then to the ISO 9001 certified ALS Global laboratory in Lima, Peru.

30 gram nominal weight samples are then subject to fire assay and AAS analysis for gold with gravimetric re-finish for overlimit assays of >10g/t. ICP-MS Ultra-Trace level multi-element four-acid digest analyses is 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 exploration plans in Colombia and the funding from Monte Águila of those plans, Monte Águila's decision to continue with the Exploration and Option agreement, the ability for Loryser to continue and finalize the remediation in Uruguay, the ability to implement the Creditors' Agreement successfully as well as continuation of the business of the Company as a going concern and other events or conditions that may occur in the future. 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 implementation 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. 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, those as described in Section "Risks Factors" of the MD&A and the Annual Information Form. 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.

This information is provided by RNS, the news service of the London Stock Exchange. RNS is approved by the Financial Conduct Authority to act as a Primary Information Provider in the United Kingdom. Terms and conditions relating to the use and distribution of this information may apply. For further information, please contact rns@lseg.com or visit www.rns.com.

SOURCE: Orosur Mining Inc.