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Aldebaran and Centauri Announce Significant Increase in Mineral Resources for the Rio Grande Gold-Copper Project in Salta, Argentina

Resource Estimates

NEWS RELEASE

Aldebaran and Centauri Announce Significant Increase in Mineral Resources

for the Rio Grande Gold-Copper Project in Salta, Argentina

VANCOUVER, CANADA (March 2, 2026) – Aldebaran Resources Inc. (“Aldebaran” or the “Company”) (TSX-

V: ALDE, OTCQX: ADBRF) and Centauri Minerals Inc. (“Centauri”) are pleased to announce the results of an

updated mineral resource estimate for the Rio Grande gold-copper project in Salta, Argentina (the “MRE”).

Highlights

• Indicated Resources containing 1.45 million ounces of gold, 384,000 tonnes of copper and 12.7 million

ounces of silver

o 153.7 million tonnes grading 0.29 g/t gold, 0.25% copper and 2.6 g/t silver

• Inferred Resources containing 1.55 million ounces of gold, 420,000 tonnes of copper and 17.8 million

ounces of silver

o 220.8 million tonnes grading 0.22 g/t gold, 0.19% copper and 2.5 g/t silver

• Mineralization is still open in several directions, with significant porphyry potential beneath the

current resource, with historical drilling hitting 257.2 m of 1.20 g/t gold, and 0.53% copper in porphyry

dykes

Sam Leung, Chief Executive Officer and Director of Centauri, commented: “This new mineral resource estimate

is fresh evidence that encourages modern exploration and future studies on the Rio Grande gold-copper project. With

no drilling or targeting programs since 2012, Centauri now has the exciting opportunity to apply modern geophysical

and geochemical tools ahead of future drilling programs on a project that already contains a substantial mineral

inventory. With this resource in hand, a drill program planned for later this year and five additional exploration

projects in our portfolio, Centauri is well set up to move forward to becoming a public company in the first half of

2026.”

Dr. Kevin B. Heather, Chief Geological Officer of Aldebaran Resources and Technical Advisor to Centauri,

commented: “I have been directly involved in the exploration at the Rio Grande gold-copper project since 2004 and

we have always felt the project needed additional exploration to realize its full potential. The MRE reported here

marks a significant milestone in the resurrection of the project, and I look forward to working with the Centauri team

to unlock significant value in the future.”

Mineral Resource Estimate

SLR Consulting (Canada) Ltd. (“SLR”) was retained by Centauri to complete a National Instrument (“NI”) 43-101

Technical Report and Mineral Resource Estimate update for the Rio Grande gold-copper project, located in Salta

Province, Argentina. The Rio Grande gold-copper property is located in the Altiplano of northwest Argentina and

supported by established infrastructure that services regional mines. The property ranges in elevation between 3,700

m and 4,700 m above sea level and is located approximately 260 km west of the city of Salta, 40 km east of the Chilean

border, and 9 km from the operating Lindero gold-copper mine. SLR visited the Rio Grande property from December

5 to 7, 2025.

To generate a new resource pit shell, SLR applied new Whittle input parameters to the 2018 resource block model

from the NI 43-101 Technical Report and MRE completed by Roscoe Postle Associates Inc. (“RPA” – since acquired

by SLR in 2019) and dated August 17, 2018. There has been no new drilling or trenching work carried out at Rio

Grande since 2013.

RPA used Datamine Studio RM and Leapfrog Geo software to build the resource block model. The resource database

contains drilling and trenching data to the end of November 2012. The database is comprised of 124 drill holes for a

total of 74,201 m of drilling and 84 trenches with a total length of 9,489 m. Both drill holes and trenches were used

for resource estimation. Wireframes for geology and mineralization were constructed in Leapfrog Geo based on

geology sections, assay results, and lithological information. Assays were capped to various levels based on

exploratory data analysis and then composited to four metre lengths.

Wireframes were filled with blocks measuring 10 m by 10 m by 10 m with sub -celling at wireframe boundaries.

Blocks were interpolated with grade using Ordinary Kriging. Block estimates were validated using industry-standard

validation techniques. Classification of blocks was based on distance criteria. Definitions for resource categories are

consistent with CIM (2014) definitions as incorporated into NI 43-101. Blocks were classified as Indicated and

Inferred based on the following criteria:

• Indicated Mineral Resources: Blocks located within areas drilled at 100 m spacing and demonstrating

reasonable continuity above the cut-off grade; and

• Inferred Mineral Resources: Blocks located within 200 m of the nearest drill hole.

The Rio Grande project is situated next to the operating Lindero Au-Cu mine (Figure 1) and it includes five Mineral

Resource areas, ranked by relative contribution: Discovery–Sofía, Central (West and East), North, Southwest, and

Seven (Figure 2).

The conceptual processing strategy for Rio Grande includes Heap Leach with SART for oxide material, a combined

Heap Leach–SART and flotation approach for transitional material, and flotation for sulphide material. While several

viable gold and copper recovery options have been evaluated, the final process flowsheet has not yet been defined and

will require additional metallurgical test work. Each process assumes different recoveries for gold, copper, and silver.

The updated MRE for Rio Grande is provided in Table 1. A supporting NI 43-101 Technical Report will be filed on

SEDAR at www.sedarplus.com within 45 days.

Table 1: Rio Grande Open Pit Mineral Resource Estimate - February 15, 2026

Category Oxidation

Tonnes

(Mt)

Au

(g/t)

Cu

(%)

Ag

(g/t)

Au

(koz)

Cu

(kt)

Ag

(Moz)

Indicated

Oxide 94.1 0.26 0.20 2.1 781 188 6.3

Transitional 47.3 0.34 0.33 3.6 523 156 5.5

Sulphide 12.3 0.36 0.29 2.3 144 36 0.9

Indicated 153.7 0.29 0.25 2.6 1,448 384 12.7

Inferred

Oxide 144.5 0.19 0.16 2.2 898 231 10.3

Transitional 75.6 0.26 0.24 3.0 643 181 7.4

Sulphide 0.7 0.25 0.24 4.1 6 2 0.1

Inferred 220.8 0.22 0.19 2.5 1,547 420 17.8

Notes:

1) CIM (2014) definitions were followed for Mineral Resources.

2) Mineral Resources are reported within a preliminary open pit resource shell.

3) The quantity and grade of reported Inferred Mineral Resources in the updated MRE are uncertain in nature

and there has been insufficient exploration to define these Inferred Mineral Resources as Indicated Mineral

Resources. However, it is reasonably expected that the majority of Inferred Mineral Resources could be

upgraded to Indicated Mineral Resources with continued exploration.

4) Mineral Resources are estimated at a net smelter return (NSR) cut-off grade of US$10.25/t for oxide.

5) US$15.00/t for Transition and US$9.50/t for sulphide.

6) Mineral Resources are estimated using a long-term gold price of US$3,000 per ounce, copper price of

US$4.50 per pound and silver price of US$45 per ounce.

7) Bulk density is 2.41 t/m³ oxide, 2.50 t/m³ oxide, and 2.62 t/m³ sulphide.

8) Metallurgical recoveries vary from 83% to 90% for gold, 29% to 64% for copper, and 0% to 41% for silver.

9) Numbers may not add due to rounding.

10) The updated MRE for Rio Grande may be materially affected by environmental, permitting, legal, title,

taxation, socio-political, marketing or other relevant issues.

Exploration Potential

Mineralization at Rio Grande remains open at depth in all of the known zones, particularly in the Sofia and Southwest

zones. Drilling completed to date has primarily tested the upper portions of the mineralized system, however many of

the existing drill holes terminated in sulphide mineralization. In addition, geological interpretation indicates potential

for deeper sulphide extensions of the known zones, with historic drilling intercepting mineralization in porphyry dykes

whose source has yet to be discovered. This potential is conceptual in nature, and insufficient drilling has been

completed to define additional Mineral Resources; however, the observed continuity of alteration and structural

controls supports continued exploration.

Centauri Next Steps

Centauri is currently working on the legal and commercial requirements to complete the previously announced spinout

and go-public event, expected to be completed in the first half of 2026 . In addition, Centauri is building out a

management and exploration team to advance the exploration portfolio, including developing new drill targets for the

Rio Grande project with the intention to commence a drill program on the project in 2026.

Value to Aldebaran Shareholders

Aldebaran and Centauri have executed a definitive share transfer agreement pursuant to which Centauri will acquire

all of the shares of Aldebaran Argentina S.A. and Minera El Toro S.A., the Aldebaran subsidiaries that hold the Rio

Grande, Aguas Calientes, and four other early-stage mineral exploration properties in Argentina. In exchange,

Aldebaran will receive 40,000,000 common shares (representing approximately 78% of the currently outstanding

Centauri shares, with the balance owned by investors in the recent placement by Centauri. The share transfer is subject

to certain conditions, and closing is expected to occur in the first quarter of 2026 (see Company news release dated

October 24, 2025). Aldebaran intends to distribute shares of Centauri to Aldebaran shareholders upon a go-public

event for Centauri. Aldebaran may elect to distribute the Centauri shares all at once or in stages and may retain a

minority interest in Centauri. The formation of Centauri allows Aldebaran shareholders to maintain their exposure to

the Altar copper-gold project in San Juan, Argentina, while also receiving additional value from the other properties

currently owned by Aldebaran through the shares in Centauri that they will ultimately receive.

Qualified Person’s Statement

The updated Mineral Resource estimate was prepared by Mr. Benjamin Sanfurgo FAusIMM, ChMC, SLR Managing

Principal Geologist. Mr. Sanfurgo is an independent qualified person (“QP”) as defined by NI 43-101. Mr. Sanfurgo

has reviewed, verified and approved the technical information related to the MRE in this announcement.

For further information or to subscribe to the Centauri news list, please contact:

Sam Leung

CEO and Director

Centauri Minerals Inc.

Phone: +1 416 206 4187

Email: [email protected]

Ben Cherrington

Manager, Investor Relations

Aldebaran Resources Inc.

Phone: +1 347 394-2728 or +44 7538 244 208

Email: [email protected]

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. (“IMC”) and based on

the drilling completed up to and including the 2023-24 field season (independent technical report prepared by IMC,

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 for Altar, prepared by SRK Consulting Inc. (“SRK”) (independent

technical report prepared by SRK, 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).

About Centauri Minerals Inc.

Centauri Minerals Inc. is a new mineral exploration company focused on Northern Argentina, a mining region of

increasing global significance. Centauri holds 100%-interest in a portfolio of exploration projects spanning over

43,000 hectares in the provinces of Salta, Catamarca and Jujuy, which was spun-out from Aldebaran Resources Inc.

The most advanced is the Rio Grande gold-copper project located in Salta, which has an independent NI 43-101

compliant mineral resource estimate that highlights significant gold and copper quantities. Centauri has offices and

facilities in Salta, Argentina and Vancouver, Canada. It is currently a private company majority owned by Aldebaran

Resources Inc. with plans to become a public company in 2026.

Forward-Looking Statements

Certain statements regarding Aldebaran, including management's assessment of future-plans and operations, may constitute

forward-looking statements under applicable securities laws and necessarily involve known and unknown risks and uncertainties,

most of which are beyond Aldebaran's control. Often, but not always, forward-looking statements or information can be identified

by the use of words such as "plans", "expects" or "does not expect", "is expected", "budget", "scheduled", "estimates", "forecasts",

"intends", "anticipates" or "does not anticipate" or "believes" or variations of such words and phrases or statements that certain

actions, events or results "may", "could", "would", "might" or "will" be taken, occur or be achieved.

Specifically, and without limitation, all statements included in this press release that address activities, events or developments

that Aldebaran expects or anticipates will or may occur in the future, including the potential of the Rio Grande Project, the amounts

and types of Mineral Resources and the recoverability thereof, timing for filing the updated MRE, the significance of exploration

results, the ability to continue exploration, future exploration and development plans, corporate and technical objectives, proposed

spinout of properties into a newly formed company described herein, the financing plans of Centauri, the expected structure of the

proposed transactions, the intent to have Centauri shares listed on an exchange, and management's assessment of future plans and

operations and statements with respect to the completion of the anticipated exploration and development programs, may constitute

forward-looking statements under applicable securities laws and necessarily involve known and unknown risks and uncertainties,

most of which are beyond Aldebaran's control. Factors that could affect outcomes include future prices and the supply of metals,

future demand for metals, results of drilling and other exploration activities, the ability of exploration results to accurately predict

mineralization, errors in geological modelling, environmental liabilities, general business, economic, competitive, political and

social uncertainties, risks of the mining industry, governmental approvals, the inability to obtain satisfactory financing for

Centauri, and inability to obtain the necessary approvals for the proposed transactions. These risks may cause actual financial

and operating results, performance, levels of activity and achievements to differ materially from those expressed in, or implied by,

such forward-looking statements. Although Aldebaran believes that the expectations represented in such forward -looking

statements are reasonable, there can be no assurance that such expectations will prove to be correct . The forward-looking

statements contained in this press release are made as of the date hereof and Aldebaran does not undertake any obligation to

publicly update or revise any forward-looking statements or information, whether as a result of new information, future events or

otherwise, unless so required by applicable securities law.

Figure 1: Rio Grande Project Location Map– approximately 9 km northwest of the operating Lindero gold

copper mine (Fortuna Mining Corp.)

Figure 2: Rio Grande Mineral Resource Areas and Resource Pit Shell

Figure 3: Rio Grande Mineral Resource Block Model and Resource Pit Shell