Badania zróżnicowania składu chemicznego Cr spineli w obrębie masywu skał ultramaficznych na przykładzie SE Kosowa – zastosowanie w poszukiwaniach złóż i wzbogacaniu rud chromu

Abstract

Study on diversity of Cr spinel composition within the ultramafic massif based on the example of SE Kosovo – implications for chromium deposit exploration and beneficiation.A b s t r a c t. New data on chemistry of Cr spinels hosted within the ultramafic massif located in SE Kosovo show variations in their primary composition, which depends on ore and rock types. Spinels form disseminated and vein type ores and accessory spinels in peridotites are characterized by lower Cr and higher Fe concentrations in comparison to spinels making up massive ores. Concentrations of these metals increase in altered spinels both in ores and peridotites. Contents ofMnand Zn tend to be higher in accessory spinels than in spinels occurring in ores. The lower Cr:Fe ratio for Cr-rich spinels in disseminated ores in relations to chromite in massive ores may have an influence on their industrial usefulness. The use of EPMA-WDS technique for detrital spinels should be considered as an effective tool for chromium deposit exploration, especially in greenfield projects, to assess an ultramafic massif potential for hosting rich ores. Chemical analyses of spinels are recommended in planning a beneficiation process for the low-grade chromite ores, in order to obtain high quality concentrates.