Mr. Claude Dufresne reports

TINTINA MINES INTERSECTS 460M AT 0.50% CUEQ AT THE DOS AMIGOS COPPER-GOLD PROJECT IN CHILE

Tintina Mines Ltd. has received initial drilling results at its wholly owned Dos Amigos project, located in the Atacama region of Chile. Building on the project's existing mineral resource estimate and 2026 preliminary economic assessment (PEA), the drilling program is designed to support conversion of the inferred mineral resources to the indicated category in support of the planned feasibility study.

Highlights include 460 metres at 0.50 per cent copper equivalent in SDDK26-001 from 200 m depth to end-of-hole (0.31 per cent Cu and 0.24 gram per tonne gold), including:

• 112 m at 0.55 per cent CuEq from 200 m depth (0.36 per cent Cu and 0.26 g/t Au);
• 98 m at 0.63 per cent CuEq from 380 m depth (0.41 per cent Cu and 0.29 g/t Au);
• 166 m at 0.50 per cent CuEq from 494 m depth (0.31 per cent Cu and 0.25 g/t Au).

Claude Dufresne, chief executive officer of Tintina Mines, stated: "Our first hole of 2026 intersected 460 metres of mineralization to end of hole, including moderate grades at the base of the pit in an area previously interpreted as low grade. These results reinforce our commitment to advancing Dos Amigos toward development as a significant copper-gold operation in Chile's Atacama region. Derisking the existing mineral resource is our key priority, and this hole supports mineralization continuity within areas currently classified as inferred. With a fourth rig arriving on site, we will continue testing the deposit's boundaries, which remain open in most directions, with the aim of expanding the company's mineral resource base."

Drilling program overview

The company is currently increasing drilling activities on site, with an initial focus on defining the edges of the deposit and stepping out into inferred portions of the mineral resource. Three rigs are currently operating 24 hours a day, with a fourth arriving imminently on site. Drilling activities are currently concentrated in and around the Dos Amigos open pit, where the majority of the primary sulphide resource is located within an approximately 700-metre-by-500-metre footprint.

Drill hole SDDK26-001

Drill hole SDDK26-001 was collared to the west of the interpreted contact between the Dos Amigos porphyry and the precursor intrusion and drilled toward the east at a dip of approximately 74 degrees.

Drilling initially traversed a zone of low-grade phyllic alteration (quartz-sericite-pyrite, D-vein assemblages) within the precursor intrusion until approximately 200 m depth, where a contact breccia was encountered adjacent to the Dos Amigos quartz-diorite porphyry until 224 m depth. From 224 m depth, M-type and A-type veins became more abundant, with a visual increase in potassic alteration and magnetite content. Chalcopyrite and pyrite abundances varied until the end of the hole and were closely correlated with vein intensity and potassic alteration. Chalcocite was logged uphole associated with the contact breccia in deeply weathered ground.

The copper and gold grades encountered in SDDK26-001 correspond well with the block model underpinning the company's 2026 PEA, with a good correlation between medium-grade and high-grade zones.

At the base of the pit design, SDDK26-001 intersected moderate grades (approximately 0.50 per cent CuEq) in an area previously interpreted as low grade.

Although SDDK26-001 was terminated shortly beneath the final pit design (as per the 2026 PEA), the company intends to continue selected drill holes at depth to prove the vertical continuity of the Dos Amigos porphyry.

Drilling costs and performance are tracking in line with budget, and samples are being continuously delivered to the laboratory. The company looks forward to updating the market when additional drilling results are received and validated.

Quality control and quality assurance

Drilling in 2026 is conducted using HQ diameter, with core extracted from drill tubes and sealed in core boxes with appropriate depth markers. Once transported from the drill rig to the on-site logging area, drill core is logged for lithology, alteration, veining and structure, with magnetic susceptibility and geotechnical/recovery parameters also collected. Density measurements are collected before the drill core is marked up for sampling at two-metre intervals with breaks on significant geological boundaries. Drill core is cut in half using a core saw, with one-half sent to ALS Global, an independent ISO/IEC 17025-accredited laboratory, for sample preparation and analysis using an ore-grade four-acid digest (Cu-AA62) and multielement analysis (ME-ICP41). In addition, gold is analyzed using a 30-gram fire assay method (Au-AA23) and weathered samples are selected for sequential copper leach test work. The company applies a rigorous QA/QC program involving certified standards, coarse and fine blanks, one-fourth core duplicates, and pulp duplicates. The remaining one-half core is stored at the company's secure core warehouse in Domeyko.

Qualified person

All scientific and technical information contained in this news release has been reviewed and approved by James Purchase, PGeo, vice-president, exploration, of the company, a qualified person for the purposes of National Instrument 43-101. Mr. Purchase is not independent of the company.

About Tintina Mines Ltd.

Tintina Mines is a TSX Venture Exchange-listed copper-gold exploration and development company advancing the wholly owned Dos Amigos copper-gold project, formerly the Domeyko Sulfuros project, in the Atacama region of Chile through its wholly owned Chilean subsidiary, Andean Belt Resources SpA.

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