Aldebaran Resources Inc. (TSX-V: ALDE, OTCQX: ADBRF) is pleased to provide results of five holes from the infill drilling program at the Altar project in San Juan, Argentina. The goal of these holes was to upgrade resource blocks classified as Inferred to the Measured & Indicated categories.

Highlights

ALD-26-049EXT

• 936.00 m of 0.66% CuEq from 130 m depth
  • Including 94 m of 0.79% CuEq from 138 m depth
  • Including 352 m of 0.84% CuEq from 264 m de pth
    • Including 194 m of 0.99% CuEq from 346 m depth
  • Including 87 m of 0.77% CuEq from 976 m depth

ALD-26-159EXT

• 1,048 m of 0.40% CuEq from 260 m depth
  • Including 490 m of 0.52% CuEq from 260 m depth
    • Including 216 m of 0.70% CuEq from 262 m depth

ALD-26-171EXT

• 1,353 m of 0.29% CuEq from 70 m depth
  • Including 274 m of 0.36% CuEq from 831 m depth

ALD- 26-175EXT

• 1,270 m of 0.29% CuEq from 74 m depth

ALD-26-021EXT

• 190 m of 0.22% CuEq from 26 m depth
• 164 m of 0.29% CuEq from 928 m depth

John Black, Chief Executive Officer of Aldebaran, commented: “The 2025-2026 infill drilling program is well underway, and the results today demonstrate the consistency of mineralization at the Altar project. These holes will provide valuable information as we move toward a resource update and pre-feasibility study.”

Kevin B. Heather, Chief Geological Officer of Aldebaran, commented: “The current 2025-2026 infill drilling program, along with the 2024-2025 infill program, are critical for mineral resource conversion from the Inferred to the Measured and Indicated categories; neither of which are reflected in the current 2024 mineral resource estimate. Only Measured and Indicated resource blocks can be considered in a prefeasibility study and for the first time in the history of the Altar project, we will be declaring Proven and Probable reserves, which is a significant step in the derisking process for the project.”

Table 1 below shows detailed assays for all five holes. Figure 1 displays a plan map of the completed drill hole locations, while Figures 2 to 5 display cross sections of the holes reported herein. Holes with the suffix EXT are extensions of previously drilled holes.

Project Update

The Company is actively drilling with six rigs on the property. The focus of the program is to complete both infill and geotechnical drilling that will be necessary for the upcoming pre-feasibility study. Upon completion of this year’s drilling, the Company will complete an updated mineral resource estimate, which is anticipated for Q3-2026. SRK Consulting Inc. has been hired to complete the MRE. The Company will also drill water wells this field season as part of its water-balance studies, and continues to collect environmental data, both of which are essential for the PFS and beyond. The Company has engaged SRK Consulting Inc. (Denver) as lead consultants for the PFS, with Knight Piesold as a subcontractor. The Company has also engaged Whittle Consulting Ltd to complete an optimization of the mine plan, which will be done in advance of developing the PFS. The analysis completed by Whittle will apply their integrated strategic planning methodology; an approach to long-term p lanning that evaluates and enhances the value of projects by considering all parts of the mining system across the value chain, all time periods, and all stakeholders. The scope of the PFS has broadened from what the Company had previously anticipated, and as such, the PFS is now expected to be completed in Q2/Q3-2027. The deadline for companies in Argentina to apply for the RIGI tax incentives and benefits has been extended by President Javier Milei to July 2027. The Company intends to submit a RIGI application in advance of the deadline but will now use the extended deadline to collect additional information before submission. It is anticipated that the Company will submit its application by Q1-2027.

Qualified Person

The scientific and technical data contained in this news release has been reviewed and approved by Dr. Kevin B. Heather, B.Sc. (Hons), M.Sc, Ph.D, FAusIMM, FGS, Chief Geological Officer and director of Aldebaran, who se rves as the qualified person (QP) under the definitions of National Instrument 43-101.

About Aldebaran Resources Inc. 

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 (independent technical report prepared by Independent Mining Consultants Inc., Tucson, Arizona, titled “Technical Report, Estimated Mineral Resources, Altar Project, San Juan Province, Argentina“, dated December 31, 2024 – see news release dated November 25, 2024). In October 2025 the Company announced a Preliminary Economic Assessment (PEA) f or the Altar Project (independent technical report prepared by SRK Consulting Inc, Denver, Colorado, titled “NI 43-101 Technical Report Preliminary Economic Assessment Altar Project San Juan, Argentina”, dated September 30, 2025 – see news release dated October 30, 2025).

Figure 1 – Location Map of Drill Holes Completed in the 2025/2026 Field Season

Figure 2 – Hole ALD-26-049EXT in Cross Section

Figure 3 – Hole ALD-26-021EXT in Cross Section

Figure 4 – Holes ALD-26-159EXT and ALD-26-175EXT in Cross Section

Figure 5 – Holes ALD-26 -159EXT and ALD-26-171EXT in Cross Section