Aldebaran Resources posts drill results from Altar Copper-Gold Project, San Juan, Argentina

Aldebaran Resources Inc. [TSXV: ALDE; OTCQX: ADBRF] provided results from all remaining holes of the 2025-2026 infill and geotechnical drilling program at the Altar Project in San Juan, Argentina. The drilling program was designed to upgrade Inferred resources to the higher-confidence Measured and Indicated categories while also supporting geotechnical studies. Several of the holes reported today were drilled exclusively for geotechnical purposes in final pit wall areas where significant mineralization was not expected.

Highlights – ALD-26-260 returned 1,728.90 metres of 0.45% CuEq from 141.00 metres depth, including 1,427.90 metres of 0.52% CuEq from 442.00 metres depth, including 756.00 mteres of 0.68% CuEq from 965.00 metres depth, including 88.00 metres of 0.84% CuEq from 1,211.00 metres depth.

ALD-26-266 returned 918.80 metres of 0.62% CuEq from 59.00 metres depth, including 87.00 metres of 0.88% CuEq from 59.00 metres depth

and 302.00 metres of 0.76% CuEq from 422.00 metres depth, including 212.00 metres of 0.83% CuEq from 490.00 metres depth.

ALD-26-265 returned 901.00 metres of 0.47% CuEq from 249 metres depth, including 781.00 metres of 0.52% CuEq from 296.00 m depth, including 196.00 metres of 0.73% CuEq from 516.00 metres depth.

ALD-26-269 returned 940.70 metres of 0.49% CuEq from 63.00 metres depth, including 165.00 metres of 0.80% CuEq from 533.00 metres depth and 227.00 metres of 0.60% CuEq from 771.00 metres depth.

ALD-26-271 returned 841.90 metres of 0.54% CuEq from 193.00 metres depth, including 253.00 metres of 0.73% CuEq from 722.00 metres depth.

John Black, CEO of Aldebaran, commented: “A mineralized interval exceeding 1.7 km in a single drill hole underscores the immense scale of the Altar system. As we move toward our updated mineral resource estimate, we will be incorporating more than 40,000 metres of drilling completed at the main Altar deposit since the last resource estimate in late 2024, as well as approximately 30,000 metres of drilling completed at the adjacent Radio Porphyry target.

Radio Porphyry has never been included in a mineral resource estimate, making this an important milestone for the project. We believe the 2026 resource update will better demonstrate the scale and growth potential of the broader Altar Project and position us well for the Pre-Feasibility Study scheduled for completion in 2027.”

Kevin B. Heather, Chief Geological Officer of Aldebaran, commented: “With the release of this final batch of drill hole results, the Altar Project continues to amaze us with long continuous intervals of copper mineralization. The 2025-2026 drilling campaign results have exceeded our expectations, and while we were waiting on these final results to arrive, we have been busy refining and improving our geological and geotechnical models based on this recent drilling. Collectively this bodes well for the upcoming mineral resource estimate and the pre-feasibility study.”
Aldebaran is a mineral exploration company that was spun out of Regulus Resources Inc. in 2018 and has the same core management team. Aldebaran holds an 80% interest in the Altar copper-gold project in San Juan Province, Argentina. The Altar project hosts multiple porphyry copper-gold deposits with potential for additional discoveries. Altar forms part of a cluster of world-class porphyry copper deposits which includes Los Pelambres (Antofagasta Minerals), El Pachón (Glencore), and Los Azules (McEwen Copper). In November 2024, the company announced an updated mineral resource estimate for Altar, prepared by Independent Mining Consultants Inc. and based on the drilling completed up to and including the 2023-24 field season.

In October 2025 the company announced a Preliminary Economic Assessment (PEA) for the Altar Project (independent technical report prepared by SRK Consulting Inc, Denver, Colorado.