Altamira Gold Intersects 395.5m @ 0.4 g/t gold in First Deep Drill Hole at Maria Bonita, Expanding Mineralized System, Cajueiro District, Brazil

Vancouver, British Columbia--(Newsfile Corp. - October 15, 2025) - Altamira Gold Corp. (TSXV: ALTA) (FSE: T6UP) (OTCQB: EQTRF) ("Altamira" or the "Company") is pleased to report assay results from drill hole MBA032, the first deep drill hole below the Maria Bonita porphyry gold mineral resource, which forms part of the Cajueiro district and where ongoing drilling is directed at enlarging the mineral resource footprint and defining its depth extent.

Highlights:

• Drill hole MBA032 at Maria Bonita returned 395.5m @ 0.4g/t gold from 44.5m depth in quartz porphyry intrusive rocks

• MBA032 was located 50m to the south of MBA029 which previously intersected 213m @ 0.8 g/t gold including 146m @ 1.0 g/t gold and significantly extends the size of the mineralized porphyry system, particularly at depth

• Gold values returned from MBA032 are remarkably continuous with only three 1 meter samples exceeding 2g/t gold in the pervasively mineralized interval

• The higher grade core to the Maria Bonita gold deposit, which is interpreted to plunge to the south-east will be targeted by drill hole MBA033 and further deep drill holes during this drill campaign

CEO Mike Bennett commented; "The first deep drill hole at Maria Bonita has demonstrated that the quartz porphyry intrusion is mineralized throughout. Results from MBA032 indicate that the mineralized system is considerably larger than previously thought, which has important implications for growing the resource base. The very consistent grade of the quartz porphyry at Maria Bonita, together with indications of a higher-grade core averaging plus 1g/t gold, and the significant size of the mineralized system, all suggest the possibility of a considerably larger mineralized system than previously envisaged.

Additional drilling is currently in progress aimed at further defining the down-plunge extension of the higher-grade core to the deposit that sub-crops in the area of the initial drilling and was intersected by drill hole MBA029 which returned 146m @ 1g/t Au from 23m depth. This zone is interpreted to plunge to the southeast and remains open."

CAJUEIRO DISTRICT

The Cajueiro district is located approximately 75km NW of the town of Alta Floresta in the state of Mato Grosso (Figure 1) in central western Brazil. The project is easily accessible by road, lies on open farmland and has grid power and a local water supply. Cajueiro is the most advanced of the key projects that Altamira controls in the region (Figure 1).

Figure 1: Location of Altamira Gold's projects in the Alta Floresta Belt.

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The Cajueiro district consists of two independently estimated gold mineral resources at Cajueiro Central and Maria Bonita, plus a series of additional untested exploration targets within a radius of 8km of Cajueiro Central.

The Cajueiro Central area has a current open pit resource¹ of 5.66Mt @ 1.02 g/t gold for a total of 185,000 oz in the Indicated Resource category and 12.66Mt @ 1.26 g/t gold for a total of 515,000 oz in the Inferred Resource category (estimated using a cut-off grade of 0.25g/t gold and a gold price of US$1,500/oz).

The Maria Bonita open pit resource consists of Indicated Resources of 24.19Mt @ 0.46g/t gold (for a total of 357,800oz) and Inferred Resources of 25.64Mt @ 0.44g/t gold (for a total of 362,400oz)². These resources were calculated using a 0.2 g/t gold cut-off grade and a gold price of US$2,780/oz. These resources include near-surface saprolite Indicated Resources of 2.02Mt @ 0.59g/t gold (38,000oz) and Inferred Resources of 0.68Mt @ 0.40g/t gold (8,700oz).

The Maria Bonita porphyry gold deposit forms part of a district-scale portfolio of prospects that are interpreted as having a similar geological origin. Gold mineralization, which is defined by the source zones of a 15km stretch of former alluvial deposits worked along the Teles Pires river, is related to a pronounced east-west corridor extending over 8km and defined by both an alignment of gold anomalies in soils and rock chips and a set of sub-cropping intrusions of different ages and compositions, implying a long standing and deep-seated crustal structure.

Figure 2: Cajueiro district mineral resources at Cajueiro Central and Maria Bonita (white labels for sub-sectors) and prospects (yellow labels). An alignment of six of the targets occur in close spatial association to a pronounced east-west fault corridor marked by later gabbroic dykes. 

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Maria Bonita Drilling

The objective of the current drill program at Maria Bonita is to enlarge the footprint of the known mineral resource by drill testing for potential extensions to the existing resource, including its depth extent, and new satellite targets.

The first drill hole, MBA032, was drilled 100m south of MBA029 and was completed to a depth of 546 metres and intersected the same mineralized quartz porphyry intrusive that was intersected in previous drilling (see Figure 3). The hole returned 395.5m @ 0.4 g/t gold. As with previous holes, the mineralization is remarkably consistent with a highest single assay interval of 5.96 g/t gold being returned from MBA032.

There is notably more brecciation in the core from MBA032 compared to MBA029, located to the north on the same section which intersected 146m @1.0g/t gold from 23m depth (see press release dated May 22, 2024). This may indicate that MBA032 was drilled closer to the edge of the higher-grade section of the mineralized intrusive body than MB029.

Figure 3: Composite drill section including MBA032 and previously reported holes MBA029, MBA013 and MBA031, showing the geology and composite grade intervals plus the previously optimised pit profile for the NI43-101 mineral resource estimate.

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Table 1: Bulk assay intervals over 0.5g/t gold showing the consistency of values in relation to peak assay values (normally for 1 metre samples).

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The interpretation of the drill results is ongoing to better guide a second deep drill hole, currently underway, collared 100m to the east of MBA032. This hole is directed at the south-east plunge continuation of the core of the mineral resource. (Figure 4).

Figure 4: Locations of drill holes from the past campaign (white) and the current campaign (yellow). The background shows interpreted major structures within the broad, trapezoid-shaped magnetic low that hosts the alteration and mineralization. The optimised pit outline is derived from the maiden mineral resource estimate² (June 2025).

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Qualified Person

Guillermo Hughes, FAIG and M Aus IMM., a consultant to the Company as well as a Qualified Person as defined by National Instrument 43-101, supervised the preparation of the technical information in this news release.

About Altamira Gold Corp.

The Company is focused on the exploration and development of gold projects within western central Brazil, strategically advancing five projects spanning over 100,000 hectares within the prolific Juruena Gold Belt-an area that has historically yielded over 6 million ounces of placer gold³. The Company's advanced Cajueiro project contains two gold deposits. The central area comprises NI 43-101 resources of 5.66Mt @ 1.02 g/t gold for a total of 185,000 oz in the Indicated Resource category and 12.66Mt @ 1.26 g/t gold for a total of 515,000oz in the Inferred Resource category. In addition, the Maria Bonita gold deposit comprises additional open pit Indicated Resources of 24.19Mt @ 0.46g/t for a total of 357,800oz, and Inferred Resources of 25.64Mt @ 0.44g/t for a total of 362,400oz.

Ongoing exploration and fieldwork at Cajueiro indicate the presence of multiple porphyry gold systems, reinforcing its potential for district-scale development. These hard-rock gold sources align with historical alluvial gold production, highlighting the region's exceptional gold endowment and potential scalability. With two independently established mineral resources, a highly prospective geological setting and a track record of significant discoveries, the Company is well-positioned to unlock further value across its extensive land package.

¹NI 43-101 Technical Report, Cajueiro Project, Mineral Resource Estimate: Global Resource Engineering, Denver Colorado USA, 10^thOctober 2019; Authors K. Gunesch, PE; H. Samari, QP-MMSA; T. Harvey, QP-MMSA
² NI43-101 Technical Report, Mineral Resource for the Maria Bonita Prospect: VMG Consultoria, Belo Horizonte, Minas Gerais, Brazil. 12^th June 2025; Author V. Myadzel
³ Juliani, C. et al; Gold in Paleoproterozoic (2.1 to 1.77 Ga) Continental Magmatic Arcs at the Tapajós and Juruena Mineral Provinces (Amazonian Craton, Brazil): A New Frontier for the Exploration of Epithermal-Porphyry and Related Deposits. Minerals 2021, 11, 714. https://doi.org/10.3390/min11070714

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

The securities described herein have not been registered under the U.S. Securities Act or any state securities laws, and may not be offered or sold in the United States absent registration or an applicable exemption from registration requirements under the U.S. Securities Act and any applicable state securities laws.

Forward-looking Statements

Certain information contained herein constitutes "forward-looking information" under Canadian securities legislation. Forward-looking information includes, but is not limited to, statements with respect to the extension of the Warrants. Generally, forward-looking information can be identified by the use of forward-looking terminology such as "will", "intends" or variations of such words and phrases or statements that certain actions, events or results "will" occur. Forward-looking statements are based on the opinions and estimates of management as of the date such statements are made and they are subject to known and unknown risks, uncertainties and other factors that may cause the actual results to be materially different from those expressed or implied by such forward-looking statements or forward-looking information, including the receipt of all necessary regulatory approvals. Although management of the Company has attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking statements or forward-looking information, there may be other factors that cause results not to be as anticipated, estimated or intended. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements and forward-looking information. The Company will not update any forward-looking statements or forward-looking information that is incorporated by reference herein, except as required by applicable securities laws.

Notes

Gold analysis has been conducted by SGS method FAA505 (fire assay of 50g charge), with higher grade samples checked by FAA525. Analytical quality is monitored by certified references and blanks. Until dispatch, samples are stored under the supervision the Company's exploration office. The samples are couriered to the assay laboratory using a commercial contractor. Pulps are returned to the Company and archived. Drill holes results are quoted as down-hole length weighted intersections.

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