Modern analytical methods (optical and electron microscopy, X-ray microanalysis) were used to study the unique samples of sulfide ores from the Norilsk ore field from the Mining Museum collections of Saint Petersburg Mining University. Samples containing rare minerals of silver and platinum-group metals (sobolevskite, urvantsevite, sperrylite, argentopentlandite, froodite, kotulskite, and others) were studied. The chemical composition, grain sizes, aggregates, and mineral associations of more than ten noble metal minerals have been refined. The efficiency of combining various methods of electron microscopy and X-ray microanalysis for studying samples of this type is shown. The results of the work made it possible to obtain high-quality images of rare minerals, to detail information on museum objects, and to compile their scientific description. The conducted research showed the relevance of studying museum objects from known deposits of complex genesis and mineral composition in order to find and describe the samples with rare minerals.
Some samples of rapakivi granites from Salmi massif (Karelia) were investigated. The inner structure and the composition of feldspars in granites are necessary for understanding of the crystallization paths of this rock. X-ray diffractometry, cathode luminescence (CL) and microprobe analyzes were used in this study. It was found, that alkali feldspar from rapakivi granites is mixture of monoclinic and triclinic phases, and the ratio of these phases is various for different types of granites. A mirmektite zone corresponding of quartz-feldspar eutectic composition is typical for large ovoid crystals. CL and microprobe detected a compositional zoning and two types of albitization in plagioclases.
The results of studying the structure of ores of the Rubtsovskoye smelter-polymetallic deposit are presented. The material for the research were polished slides of lead-copper-zinc ores. The mineral composition of ores was studied, the order of crystallization of ore minerals was established. Differences in the structure and mineral composition of ores from different parts of the ore body were found and described. The granulometric analysis of mineral grains was carried out on a personal computer using VideoTest and Excel-98 software packages. Chalcopyrite inclusions in sphalerite were studied by electron microscopy. Conclusions were made about the conditions of ore formation and their technological properties.
The main objects of the research were the deposits of noble and non-ferrous metals of the Urals, Siberia and Novaya Zemlya. It is shown that the study of the variability of the material composition and stereometric features of ores (with computer modeling of the most important types of mineral aggregates) in the geological space is extremely important to reduce losses of useful components, predict the technological properties of mineral raw materials and identify the conditions of ore formation.
A method for characterizing the structure of copper-zinc sulfide ores by means of fractal dimensionality is presented. Fractal dimensionality allows to quantify the complexity of mineral grain boundaries in ore. This information can be the basis for predicting the disintegration of ores during concentration. The material for the research was polished thin sections of copper-zinc ores from the Alexandrinsky deposit (Ural). Measurements of fractal dimensionality were carried out by the step method on a personal computer using the programs Adobe Photoshop 7.0 and FractShop. This method is used for sulfide ores for the first time.
A method of characterizing the structure of copper-zinc sulfide ores by means of fractal dimensionality is presented. Fractal dimensionality allows to quantify the complexity of mineral grain boundaries in ore. This information can be the basis for predicting the disintegration of ores during concentration. The material for the research was polished thin sections of copper-zinc ores from the Alexandrinsky deposit (Ural). Measurements of fractal dimensionality were carried out by the step-by-step method on a personal computer using the programs Adobe Photoshop 7.0 and FractShop. This method is used for sulfide ores for the first time.
