Micromineralogy and geochemistry of sphalerites from Sulitjelma mining district, Norway

A wide range of zinc-rich to zinc-poor ore bodies characterizes the famous Caledonian pyritic copperzinc ore deposit of Sulitjelma. It is, however, observed that, in general, the sphalerites from the two main assemblage types of ores in different ore bodies display remarkably analogous minor- and traceelement geochemistry marked with comparable concentrations of individual elements. The distribution of certain common mi nor elements between sphalerite and co-existing iron-sulphide minerals tends to be regular. On the crystal scale too, the sphalerites show no evidence of physical or chemical heterogeneity. The implications of the study in deciphering equilibration or re-equilibration of ores during regional metamorphism and the probable optimum geobarometric conditions have been considered.