Strong Growth in Boliden's Mineral Resources and Reserves for 2025

Boliden's Strong Performance in Mineral Resources for 2025

In a recent announcement, Boliden reported a significant escalation in its mineral resources and reserves for the year 2025.

This surge can be attributed to a series of successful exploration projects, alongside favorable economic conditions, according to Stefan Romedahl, the Director of Business Area Mines. Key sites contributing to this remarkable output included Garpenberg, the Boliden Area, and Nautanen.

An overview of operations reveals an investment of SEK 969 million in exploration for the year, an increase from SEK 929 million in 2024. This financial backing illustrates Boliden's commitment to enhancing its mining capabilities and resource base.

Detailed Analysis of Operations

1. Aitik:
Although the Aitik mine experienced a modest decrease of 40 million tonnes in mineral reserves (down by 4%), due to ongoing mining activities, it also saw a boost in mineral resources. Measured and indicated resources peaked at 214 million tonnes (up by 36%), and inferred resources rose by 63 million tonnes (up by 20%). The nearby Liikavaara site, which commenced production in 2024, contributed significantly by processing 25% of Aitik's ore. In total, Aitik milled 39 million tonnes in 2025.

2. Nautanen:
Major resource discoveries were documented at the Nautanen site, located approximately 15 kilometers north of Aitik. Indicated resources surged by 7 million tonnes (up by 51%), while inferred resources escalated by 20 million tonnes (up by an astonishing 173%). This impressive growth was driven by both successful exploration efforts and rising metal prices.

3. The Boliden Area:
A comprehensive analysis of the Boliden area showed a total increase in mineral reserves of 2 million tonnes (up by 13%). Every mine, including Kankberg, Kristineberg, and Renström, contributed to this figure. Kankberg, in particular, benefitted from a revised gold price assumption. Furthermore, mineral resources rose across all mines and adjacent projects, with the most notable gains coming from Nyliden, now reported for the first time. The area's total mineral resource increase amounted to 3 million tonnes (up by 32% for measured and indicated resources) and 7.1 million tonnes (up by 39% for inferred resources). Notably, 1.5 million tonnes were milled in this area during 2025.

4. Garpenberg and Kevitsa:
At Garpenberg, mineral reserves saw a minor decline of 1.4 million tonnes (down by 1%), but exploration success and favorable metal prices resulted in a surge of mineral resources: measured and indicated resources rose by 16 million tonnes (up by 84%), and inferred resources increased by 11 million tonnes (up by 10%). Meanwhile, Kevitsa faced a mineral reserve drop of 9 million tonnes (down by 9%) due to mining efforts, though there was a modest increase in measured and indicated resources of 4 million tonnes (up by 2%). Changes in the mining permit environment, while renewing permits in July 2025, created an atmosphere of financial uncertainty with new tax regulations expected to increase annual costs significantly.

5. Tara:
The Tara site underwent careful reviews this year, which resulted in a 2.7 million-tonne (up by 20%) increase in mineral reserves primarily due to resource conversions. However, measured and indicated resources showed a sharp decrease of 1.2 million tonnes (down by 55%) and inferred resources dropped by 3.6 million tonnes (down by 10%). Tara managed to mill 1.44 million tonnes in 2025.

New Acquisitions and Reporting Methodology

In a strategic move, Boliden completed the acquisition of Somincor and Zinkgruvan in April 2025. This led to the inclusion of their mineral reserves and resources in Boliden's official reporting. Notably, a change in reporting methodology now differentiates mineral resources from reserves, resulting in lower resource figures for these mines.

Somincor reported a mineral reserve increase of 3.9 million tonnes (up by 19%) in copper, primarily driven by revised economic assumptions. However, indicated resources suffered a decrease of 25 million tonnes (down by 46%), chiefly due to this new reporting format. Conversely, Zinkgruvan noted minor changes in its mineral reserves but a significant fall in indicated resources due to the removal of reserves from the reporting figures.

Regulatory Compliance and Future Outlook

Boliden adheres to the operational guidelines established by the Swedish Mining Association and the PERC standards for exploring and reporting mineral resources and reserves. All summarizations concerning mineral resources and reserves are rigorously reviewed by qualified professionals to maintain transparency and adherence to regulations. Boliden aims to continue leveraging its exploration successes to further bolster its resource base while navigating the changing regulatory and economic landscapes ahead.