Mr. Brad George reports

OROSUR MINING INC ANNOUNCES OPERATIONAL UPDATE, BRAZIL

Orosur Mining Inc. has provided an update on the progress of exploration activities at its Ariquemes tin project in Brazil.

• Sampling and mapping program commenced at Ariquemes;
• Alluvial program to test effectiveness of regional work;
• Mapping north of Bom Futuro identifies mineralized granites -- samples submitted for assay.

The Ariquemes project is a large-scale tin (and associated metals) exploration project in Rondonia state, Brazil, entirely within the world-class Ariquemes tin field. The project comprises a large number of granted licences and applications that in total cover more than 3,000 square kilometres, representing the largest landholding in this key mining district.

Ariquemes project is a joint venture with Canadian-listed Meridian Mining UK, whereby Orosur has the right to earn a 75-per-cent stake in the project by investing $4-million (U.S.) in exploration over a four-year period in two stages.

As announced on May 4, 2023, a regional stream sediment program was recently completed across the entire licence area. The rationale for this program was to cover the area as quickly and as efficiently as possible and identify key higher priority zones for follow-up. This objective was successful with large areas of tin and niobium anomalism being mapped. As a result, the company has now decided to move to the next phase.

As part of the next phase, two prospects were targeted for small work programs designed to address several key geological questions. The work programs include:

• Carrying out more detailed work in one key licence area to assess the effectiveness of the regional sampling program;
• If successful, identifying as quickly as possible, a body of mineralization that demonstrates the economic potential of the region and underpins further work;
• Exploring the northeast of the large Bom Futuro mine for possible extensions or repetitions.

Oriente Novo

The Oriente Novo licence is to the far east of the main lease package.

This licence was chosen as the most attractive site for the next phase of work for several reasons:

• The area returned several stream sediment samples, highly anomalous in both tin and niobium;
• Being recently granted (unlike many other licences which remain unpublished or awaiting renewal), ground disturbing activities such as drilling are permitted;
• There was substantial historical mining both north and south of the lease (stopping at the boundary), both from primary hard rock and secondary alluvial sources;
• These two historical mining areas are connected by a long drainage system, over six km of which is within the licence area, that contained the anomalous stream sediment samples;
• The licence contains over 15 km of additional drainages that have shown anomalous results and may be the target of additional work in the future.

A small, hand-held, mechanized auger drill will be used to take samples down to five m (with a sample collected at every metre) to test the presence of surface mineralization along the length of this drainage system. In addition, at regular intervals, the auger will be pushed down to its capacity of 20 m to test the depth potential of the drainage system.

This program is expected to take approximately six weeks, but as samples will be assayed using a local XRF unit rather than being sent to a laboratory, results should be forthcoming as the survey progresses, allowing the program to be modified as it progresses.

Should the results of this work be positive in defining a substantial area of tin and niobium mineralization near surface, the company may then consider expanding the program both in terms of area, depth and infill exploration and drilling, potentially with a view to considering early-stage, pilot-scale production as allowed by the Brazilian mining code.

Paraiso -- north of Bom Futuro

The Bom Futuro tin mine is the largest mine in the region and, at its peak, was one of the largest in the world.

It was discovered accidently by local woodcutters in 1987 and then subsequently developed and mined continuously by a local co-operative which exploited both the primary hard rock mineralization and surrounding associated alluvial sources.

The operating co-operative has generally focused on exploitation of visible mineralization and has done little work to develop a full understanding of the genesis of the deposit or to explore beyond the immediate mining area.

Freely available government aeromagnetic data show that the Bom Futuro mine is situated at the southern end of a roughly 25 km long cigar-shaped structural feature, interpreted to be a fault-bounded block of basement and granite. These southwest- to northeast-trending bounding structures were possibly the primary conduits for altering fluids that created the pegmatite and greisen tin mineralization.

The northern half of this structural feature sits within the JV area but has never been explored.

Company geological teams recently visited the area for the first time -- a delay driven largely by the fact the licence has yet to be published as a granted lease, limiting what work can be done.

Most of the area is now totally cleared for cattle farming with no outcrop, other than several small granite hills with residual forest. Geological teams entered these areas and located extensive areas of altered granites and pegmatites, rich in tourmaline, somewhat similar in character to what is seen at Bom Futuro. Tourmaline (a boron silicate mineral) is a positive indicator as boron can be enriched in fractionated felsic melts and shows close association with tin and lithium mineralization.

Panning of a stream adjacent to one of these granites also returned high-grade cassiterite, suggesting proximity to a primary source.

Samples have been submitted to a local geochemical laboratory for assay, with results expected in several weeks.

Orosur chief executive officer Brad George commented:

"Work at Ariquemes project has progressed as per the planned timetable, to allow us to gradually develop our understanding of the region and the local controls on mineralization. This work is now bearing fruit, and this current phase, if successful could mark a major milestone in identifying areas of economic mineralization. At a time of encouraging tin and niobium prices, this may provide the company with valuable optionality."

About Orosur Mining Inc.

Orosur Mining is a minerals explorer and developer focused on identifying and advancing projects in South America. The company operates in Colombia, Argentina and Brazil. The company has discontinued operations in Uruguay.

Qualified person statement

The information in this news release was compiled, reviewed and verified by Brad George, BSc, honours (geology and geophysics), MBA, member of the Australian Institute of Geoscientists (MAIG), CEO of Orosur Mining 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.

Ariquemes

Stream sediment samples were taken at specific locations where drainages intersected local roads, on roughly a 10 km by five km spacing. Samples of approximately 20 litres were gathered at a depth of around 70 centimetres to one m. To avoid anthropogenic contamination, the sampling points were located at a distance from the roads. The collection process was carried out using a posthole digger, and samples were then packaged in plastic bags, sealed and labelled accordingly. Collected samples underwent a concentration process by panning to produce a concentrate of heavy minerals.

Samples were then sent to the SGS laboratory in Belo Horizonte, Minas Gerias state, for assay by inductively coupled plasma -- optical emission spectroscopy (ICP-OES) and inductively coupled plasma -- mass spectrometry (ICP-MS).

We seek Safe Harbor.