Cajueiro

Advancing one of brazil’s most promising gold deposits.

Overview

Ongoing exploration and fieldwork point to the likelihood of multiple porphyry-related gold systems at Cajueiro, creating a compelling case for district-scale discovery and development. These potential hard-rock sources align with historical alluvial gold production, underscoring the project’s robust gold endowment and potential scalability.

Extensive trenching and drilling at Cajueiro have delineated 185,000 ounces of Indicated Resources and 515,000 ounces of Inferred Resources at the Central Deposit, with substantial upside as the deposit remains open both at depth and laterally. The 2019 Mineral Resource estimate, conservatively based on a gold price of US$1,500 per ounce covers an area of around 28,000 ha. The resource remains open in several directions and recent work has identified several potential lateral extensions which will shortly be drill tested.

A maiden mineral resource estimate for the Maria Bonita porphyry gold deposit within the Cajueiro Project was released in May, 2025. Maria Bonita is a separate discovery, located 7km to the west of, and additional to, the Cajueiro Central Mineral Resource.

The updated open-pit Mineral Resource Estimate (MRE), announced in September 2026, incorporates 3,868m of additional drilling completed in 11 holes since the maiden estimate. The updated resource comprises Indicated Resources of 25.0Mt grading 0.50g/t gold, containing 403,877oz, and Inferred Resources of 70.0Mt grading 0.41g/t gold, containing 908,477oz, for a combined 1.31Moz of contained gold. The updated MRE is reported at a 0.2g/t gold cut-off grade.

A significantly higher-grade portion of the deposit has also been identified. At a 0.5g/t gold cut-off grade, this portion comprises 9.30Mt grading 0.75g/t gold (225,630oz) in the Indicated category and 11.11Mt grading 0.80g/t gold (286,859oz) in the Inferred category, for a combined 512,489oz of contained gold.

The updated resource is constrained within an optimised open-pit shell, with a calculated waste-to-mineralized material ratio of approximately 0.4:1. Mineralization remains open to the west, south and at depth, providing further opportunities for resource expansion. Drilling is underway on the newly accessible western extension of the deposit.

The broader Cajueiro district also hosts several additional drill targets, offering significant potential for further resource growth and new discoveries as exploration continues.

Project Summary

Project

Cajueiro

Location

Alta Floresta Gold Belt, Brazil

Indicated Resources

185,000oz at Central and 403,877oz at Maria Bonita

Inferred Resources

515,000oz at Central and 908,477oz at Maria Bonita

Status

Ongoing drilling & trenching

Infrastructure

Hydropower & roads

Technical Report Cajueiro Central Technical Report Maria Bonita

Stay up to date with our explorations and discoveries.

Cajueiro

Cajueiro: Anchoring a Growing Gold District in the Alta Floresta Belt

Cajueiro is more than a single project — it sits at the center of a much larger gold system emerging across Brazil’s Alta Floresta Belt. Surrounded by high-priority targets, historic placer workings, and recent discoveries like Maria Bonita, the project benefits from extensive geological data and strong infrastructure. As soil anomalies and drilling continue to define new mineralized zones, Cajueiro is shaping up to be a key driver in the belt’s next phase of gold development.

Drill core samples from Maria Bonita illustrate the main host rocks to the gold mineralization. Although there is no outcrop on the site, the gold mineralised zone sub-crops and fresh rock is found in core approximately 10 metres below the surface. Several pulses of intrusive rhyolite porphyry host the gold. Variable intensity and forms of quartz veining are accompanied by potassic alteration, indicative of the high temperature core of a porphyry alteration system. There is very little sulphide mineralization associated with the gold and neither significant accompanying base metals nor deleterious elements that may interfere with simple metallurgical processing.

Quartz unidirectional solidification textures (USTs) are observed in various sections of the core and are interpreted as the upper parts of successive intrusive porphyry pulses. These rocks may have originally crystallized at a palaeo depth of at least 3km. Since that time, erosion has removed most of the cover, however, it appears that a significant part of the intrusive phase of the porphyry system remains preserved at the current level of erosion. The different levels of erosion that may apply to other district targets, above their source porphyry intrusives, are shown in the conceptual section.

Cajueiro: Defined Gold Resources in a Proven Mining Belt

Altamira Gold’s Cajueiro Project is located in Brazil’s Alta Floresta Belt, one of South America’s most prolific gold-producing regions. The project hosts well-defined near-surface gold mineralization with room for expansion, supported by excellent infrastructure and promising metallurgy.

Investor Overview

Indicated Resources

Total Indicated at Central: 5.66 Mt @ 1.02 g/t Au. Total Indicated at Maria Bonita: 24.19Mt @ 0.46g/t Au.

185,000oz

357,800oz

Inferred Resource

Total Inferred at Central: 12.66 Mt @ 1.26 g/t Au. Total Inferred at Maria Bonita: 25.64Mt @ 0.44g/t Au.

515,000oz

362,400oz

Land Package

Long-term growth and regional footprint

22,934ha

Active exploration & drilling

Best drill intercept to date.

212m @ 0.8 g/t Au (open at depth)

Gold recovery efficiency

Gold recovery rates from metallurgical testing.

90%+

Strategic Scale, Defined Growth

Strategic Land Package in a Prolific Gold Belt

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Exploration Depth

13,390 m

Diamond drilling completed across multiple zones, helping define both resource areas and new discovery targets.

Infrastructure Advantage

1.5h

From Alta Floresta by road with major airport, well developed infrastructure supporting the agriculture industry.

Energy Advantage

18km

From the Cajueiro project to a 1.8GW “green” hydropower plant on the Teles Pires River.

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Altamira Gold provides investors with a unique opportunity to participate in the exploration and development of high-potential gold and copper projects across Brazil’s prolific Alta Floresta Belt, including its flagship Cajueiro Project and emerging discoveries at Apiacas and Santa Helena.