Mineralogical and geochemical characteristics of zircon from diorite porphyry dyke in Sergozerskoe gold occurrence (the Strel'ninsky greenstone belt, Kola region)

Mineralogical and geochemical investigation of zircon from diorite porphyry from Sergozerskoe occurrence has been carried out. Study of morphology and inner structure of zircon crystals in back scattered electron rays as well as assaying for content and distribution of Rare Earth Elements in mineral grains have given important information about conditions of crystallization and following metasomatic alteration of zircon. Zircon characteristics show that it crystallized in a melt, enriched in fluid phase. Fluid influence lasted after zircon crystallization, this reflected in uneven composition of the mineral and in configuration of REE spectra, typical for metasomatic zircon. Similar zircon characteristics have been noted in zircons from other gold occurrences in greenstone belts in the Kola region