MOBILE MIXTURES IN QUARTZ FROM THE KARELIAN-KOLA REGION

Abstract

The goal of our project was to study mixtures in quartz from the Karelian-Kola region that display high diffusive mobility. To interpret the features of the mixtures revealed, analytical results for quartz from the Kent pegmatite field, some gold deposits and other areas were used. The possible presence of mobile mixtures in this mineral was assessed, their presumable sites were located and their contribution to structural transformations was appraised. The authors note that the above problems should be approached to develop new highly pure quartz prospecting criteria and to propose efficient quartz dressing technologies. To achieve the goal, the structural heterogeneity zones of quartz were studied by the electron microscopy and EPR methods. The results obtained show that impurity atoms, affected by the electron beam of the microscope, coagulate to form large particles and concentrate in some of the deficient regions of the crystalline structure. The impurities were identified as mobile. They consist of Al, Ti, Ga, Sc, Zr, Y and Ge, which are most similar in atomic characteristics to silicon atoms. The diffusion of mobile mixtures was shown to control structural transformations in quartz. The silica regions, depleted in the above elements and affected by high temperatures, are crystallized. Crystalline structure deficiency may increase in impurity-enriched zones enriched upon irradiation of quartz. The mechanisms of introduction of mobile mixtures into the crystalline structure of quartz affected by high temperatures are discussed. The contribution of the impurities to the formation of fractures in quartz was assessed. The study shows that silica in the regions where mobile mixtures are located passes to viscous-fluid state on heating.

Keywords

• кварц карело-кольского региона
• структурные дефекты
• подвижные примеси
• просвечивающая электронная микроскопия
• эпр