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The Swedish Palaeoproterozoic is intensely mineralised. In the north, 2.5-2.0 Ga greenstone belts and 1.89 Ga terrestrial volcanic and sedimentary rocks host syngenetic Cu-(Zn) deposits, epigenetic Cu-Au deposits and apatite iron ores. The greenstones were formed in rifts within the Archaean crust, while the 1.89 Ga terrestrial volcanic rocks were probably emplaced in a continental volcanic arc setting in response to subduction in the south where the juvenile Skellefte volcanic arc was forming. This volcanic arc hosts numerous massive sulphide, epithermal and porphyry Cu-Au deposits which are related to the early stages of the arc's evolution. After accretion towards the Archaean continent and crustal thickening, several mesothermal gold lode type deposits were formed, possibly at around 1.80 Ga, in structurally favourable settings., The Swedish Palaeoproterozoic is intensely mineralised. In the north, 2.5-2.0 Ga greenstone belts and 1.89 Ga terrestrial volcanic and sedimentary rocks host syngenetic Cu-(Zn) deposits, epigenetic Cu-Au deposits and apatite iron ores. The greenstones were formed in rifts within the Archaean crust, while the 1.89 Ga terrestrial volcanic rocks were probably emplaced in a continental volcanic arc setting in response to subduction in the south where the juvenile Skellefte volcanic arc was forming. This volcanic arc hosts numerous massive sulphide, epithermal and porphyry Cu-Au deposits which are related to the early stages of the arc's evolution. After accretion towards the Archaean continent and crustal thickening, several mesothermal gold lode type deposits were formed, possibly at around 1.80 Ga, in structurally favourable settings.

The host rocks of the Aitik Cu-Au deposit consist of plutonic and volcanic rocks, the latter strongly altered and deformed. To deduce the tectonic origin of the host rocks, a comparison is presented with the widespread volcanic and plutonic rocks generated during the Svecofennian orogeny in the continental domain north of the Skellefte district. The Porphyrite Group of volcanic rocks, and the Haparanda Suite of granitoids, which were both previously interpreted as subduction-related, are chemically similar to the Aitik rocks, showing a calc-alkaline, intermediate composition. The Aitik rocks were probably formed in a compressional environment in a volcanic arc setting, corresponding to the period of subduction (at around 1.9 Ga) in the Skellefte district., The host rocks of the Aitik Cu-Au deposit consist of plutonic and volcanic rocks, the latter strongly altered and deformed. To deduce the tectonic origin of the host rocks, a comparison is presented with the widespread volcanic and plutonic rocks generated during the Svecofennian orogeny in the continental domain north of the Skellefte district. The Porphyrite Group of volcanic rocks, and the Haparanda Suite of granitoids, which were both previously interpreted as subduction-related, are chemically similar to the Aitik rocks, showing a calc-alkaline, intermediate composition. The Aitik rocks were probably formed in a compressional environment in a volcanic arc setting, corresponding to the period of subduction (at around 1.9 Ga) in the Skellefte district.