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The Gällivare area is an important producer of Fe, Cu and Au. The Cu-Au deposits are hosted by Sve-cofennian successions of volcanic and sedimentary rocks formed in an arc environment. Apatite iron ores are restricted to overlying intermediate to felsic volcanic units with intraplate characteristics. Most of the Cu-Au occurrences are spatially related to the Nautanen Deformation zone, which is a major north-northwest–oriented crustal structure.

A large-scale zoning pattern is outlined by the metal association and alteration along the Nautanen Deformation zone and to some extent across it. In the northwestern part, magnetite and locally apatite are important constituents indicating a relation to the nearby apatite iron ores. The host rock is strongly altered by K feldspar and scapolite. Towards the southeast pyrite becomes an important ore mineral, while magnetite is less abundant. This change is accompanied by an increasing Au/Cu ratio and alteration dominated by biotite or sericite.

Mineralization within the Nautanen Deformation zone is mainly disseminated in character and may represent an early phase of mineralization related to synorogenic 1. 9 Ga intrusions of intermediate composition. Vein style mineralization occurs as late phases in disseminated deposits and outside the Nauta-nen Deformation zone. This mineralization may to some extent represent remobilized products of older disseminated sulfide occurrences. The common occurrence of tourmaline in the veins and locally also molybdenite or scheelite suggests a relation to the granites of the 1.8 Ga Lina Suite. Thus, the present zoning pattern along the Nautanen Deformation zone is the product of several hydrothermal events with the 1.9 Ga mineralization possibly outlining the large-scale features.

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