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Altiplano Metals Inc.

250 Southridge NW, Suite 300

Edmonton, AB

Canada

T6H 4M9

Altiplano Intersects Santa Beatriz Vein, Receives Updated Permit, Begins Shipments to El Penon

EDMONTON, AB, September 9th, 2025 - Altiplano Metals Inc. (TSXV: APN) (WKN: A2JNFG) ("Altiplano" or the "Company") is pleased to announce operational updates at the Santa Beatriz copper-gold-iron (Cu-Au-Fe) mine, located approximately 45 kilometers south of La Serena, Chile, and 13 kilometers south of the Company's El Penon processing facility.

Highlights:

Initial tunnel development began via the 437 m level entrance and continued 63.4 m to intersect the Santa Beatriz Iron Oxide Copper Gold vein (IOCG) at the 425m level (Figure 1.).

Massive sulphides (chalcopyrite, pyrite and bornite), as well as magnetite were observed in the vein.

Mining of mineralized material has begun in two directions along the north and south vein extensions at Level 425.

September extraction is projected at 3,000 tonnes, with daily production targeted between 120 and 140 tonnes.

Shipments to the El Penon processing facility have begun supporting the production of copper/gold and iron concentrates.

New development will begin on the lower tunnel, accessed through the 414 m opening, to support mining on 2 additional operational north and south faces located at the 400m level.

Work is expected to begin the week of September 15th and Intersection of the 400m level is expected early October

The SERNAGEOMIN (the Chilean mining authority) has approved the application for mine planning and expansion at Santa Beatriz for a 42-month period. The permit includes:

extraction of up to 4,275 t/m

approval for two additional mine openings (3 in total) creating the opportunity for further expansion

Additional tonnage and extensions can be applied for as development progresses.

President and CEO Alastair McIntyre comments: "The ramp developments at the 425m and 400 m levels represent a key milestone in advancing the Santa Beatriz mine toward maximum output. Access to the vein structure at lower levels and through multiple faces enables the extraction of high-grade copper/gold and iron material supporting increased production potential. Material supplied from Santa Beatriz to our plant addresses our goal of integrating our copper/gold and iron production and processing businesses. We are also very pleased to receive the mine extension permit at Santa Beatriz providing us the opportunity to increase mineral production and sale of copper/gold and iron concentrates.

Figure 1. Section of Santa Beatriz Mine

The decision to develop the historical Santa Beatriz mine is not based on a feasibility study of mineral reserves demonstrating economic and technical viability and there is increased uncertainty of economic and technical risks of failure associated with any potential production decision.

Figure 2. Santa Beatriz Vein

Figure 3. Shipments arriving at El Penon

Altiplano has generated over C$23.8 million from the recovery and sale (after processing costs) of more than 8.2 million pounds of copper with an average grade of 1.8% Cu (Jan 2018 to Mar 2025). Cash has been re-invested into acquisition, exploration, new equipment, underground drilling, expanding underground development and production, and the completion of the El Penon copper-gold-iron processing facility located 30 km from La Serena, Chile.

About Altiplano

Altiplano Metals is a growing gold, silver, and copper company focused on the Americas. The Company has a diversified portfolio of assets that include exploration properties, a developing copper/gold/iron mine and a state-of-the-art operating copper/gold and iron processing facility. Altiplano is focused on creating long-term stakeholder value through developing safe and sustainable production, reinvesting into exploration and development, and pursuing acquisition opportunities to provide scalable upside opportunities. Management has a substantial record of success in capitalizing on opportunity, overcoming challenges and building shareholder value

Qualified Person

The technical content of this news release has been reviewed and approved by John Williamson, P.Geol., a Qualified Person as defined by National Instrument 43-101. Mr. Williamson is a Chairman and Director of Altiplano Metals Inc. and is not independent of the Company.

Metals Group

Altiplano is part of the Metals Group of Companies, led by a dynamic group of resource sector professionals with a long record of success in evaluating and advancing mining projects from exploration through to production, attracting capital, and overcoming adversity to deliver exceptional shareholder value. www.metalsgroup.com

ON BEHALF OF THE BOARD

/s/ "John Williamson"

Chairman

For further information, please contact:

Alastair McIntyre, CEO

alastairm@apnmetals.com

Tel: (416) 434 3799

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the (TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

This release includes certain statements that may be deemed "forward-looking statements". All statements in this release, other than statements of historical facts, that address exploration drilling, exploitation activities and events or developments that the Company expects are forward-looking statements. A qualified person has not done sufficient work to classify any historical estimates as current mineral resources or mineral reserves and the issuer is not treating any historical information or estimates as current mineral resources or mineral reserves. The Santa Beatriz mine was previously in private production mid 2010's with unknown production records. This material was processed and sold locally to a private processing facility. Altiplano is relying upon limited past production records, underground sampling, surface drilling and related activities to further explore, develop and potentially mine Santa Beatriz. The decision to develop the project and extract material for processing is not based on a feasibility study of mineral reserves demonstrating economic and technical viability and there is increased uncertainty and economic and technical risks of failure associated with any future potential production decision. Although the Company believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, such statements are not guarantees of future performance and actual results or developments may differ materially from those in the forward-looking statements. Factors that could cause actual results to differ materially from those in forward-looking statements include market prices, exploitation and exploration successes, continuity of mineralization, uncertainties related to the ability to obtain necessary permits, licenses and title and delays due to third party opposition, changes in government policies regarding mining and natural resource exploration and exploitation, and continued availability of capital and financing, and general economic, market or business conditions. Investors are cautioned that any such statements are not guarantees of future performance and actual results or developments may differ materially from those projected in the forward-looking statements. For more information on the Company, investors should review the Company's continuous disclosure filings that are available at www.sedarplus.ca .