Mineralogisk och malmpetrografisk studie av disseminerade sulfider i rika och fattiga prover från Kleva

Sammanfattning: The Kleva copper-nickel sulphide mineralization in Jonkoping County, southeastern Sweden, is categori-sed as an elongated mafic pluton. In this study, ore microscopy and quantitative chemical analysis using SEM -EDS have been used to describe the relative abundance and distribution of sulphides and iron oxides in disseminated samples. The overall dominant mineral ore phase is chalcopyrite. In the richer samples it is associated with pyrrho-tite and inclusions of iron oxides. In samples of lower grade, pyrite is the most dominant sulphide also filling out aertheritic textures of granular magnetite, and bordering ilmenite grains. Pentlandite is common in all samples but only contains Co in richer samples while with higher Ni content in samples of lower grade. The results presented here are interpreted in a model of enrichment in the ore. It is proposed that tension caused an influx of a magma poor in sulfur that reheated and altered the chemical balance of the already partly crystallized body.