A significant part of the primary gold reserves in the world is contained in sulphide ores, many types of which are refractory in gold processing. The deposits of refractory sulphide ores will be the main potential source of gold production in the future. The refractory gold and silver in sulphide ores can be associated with micro- and nano-sized inclusions of Au and Ag minerals as well as isomorphous, adsorbed and other species of noble metals (NM) not thoroughly investigated. For gold and gold-bearing deposits of the Urals, distribution and forms of NM were studied in base metal sulphides by laser ablation-inductively coupled plasma mass spectrometry and by neutron activation analysis. Composition of arsenopyrite and As-pyrite, proper Au and Ag minerals were identified using electron probe microanalysis. The ratio of various forms of invisible gold—which includes nanoparticles and chemically bound gold—in sulphides is discussed. Observations were also performed on about 120 synthetic crystals of NM-doped sphalerite and greenockite. In VMS ores with increasing metamorphism, C_Au and C_Ag in the major sulphides (sphalerite, chalcopyrite, pyrite) generally decrease. A portion of invisible gold also decreases —from ~65–85% to ~35–60% of the total Au. As a result of recrystallisation of ores, the invisible gold is enlarged and passes into the visible state as native gold, Au-Ag tellurides and sulphides. In the gold deposits of the Urals, the portion of invisible gold is usually <30% of the bulk Au.

The central part of the Malouralsky volcanic–plutonic belt, which includes the Manyukuyu–Vorchatinsky ore cluster, is analyzed using multispectral imagery from the Landsat-8 Earth remote sounding satellite with the aim of identifying gold deposits and compared with the Toupugol–Khanmeishor ore region. Similar features in the geological structure and location of deposits and ore deposits in the system of morphological structures are found that should help to develop predictive and prospecting indicators (geological and morphological) of gold mineralization. Three structures are distinguished via analysis of satellite images: the monogenic Novogodnenskaya structure (the Toupugol–Khanmeishorsky ore region) formed under the influence of one main geological process and morphostructures Nos. 1 and 2 (the central part of the Malouralsky volcanic–plutonic belt). These two structures are larger and more complex, with long multistage development. Magmatic chambers are located at depths of ~12 and ~16 km, respectively, for morphostructures Nos. 1 and 2; their root (focal) parts extended southward and then southwestward, respectively, during magmatic development. Prospecting for hydrothermal gold mineralization at the north of the eastern slope of the Polar Urals should be done at the periphery of the centers of large complex morphostructures with long and multistage development with signs of telescoping. Mineralization should be localized in areas of concentration of northwestern and/or northwestern lineaments and in regional fault zones that can be hundreds of kilometers long.

Large ring, arc, and radial structures have been identified by complex processing of the multispectral satellite imagery of the Landsat. These structures control the gold mineralization position in the Toupugol–Khanmeishor ore district (Novogodnenskoe ore cluster, Polar Urals). This area has been compared with the Tur’insk–Auerbakh ore district (Auerbakh ore cluster, Northern Urals). Similar geological features, regularity in the structures, and the location of gold mineralization in the system of morphostructures have been revealed. The formation depth of the magmatic chambers has been determined for the Novogodnenskoe and Auerbakh paleovolcanic structures for the first time. These chambers are located at depths of ~4 and ~20 km, respectively, in the upper and middle parts of the earth’s crust. The Novogodnenskoe structure is a monogenic structure. It was formed under the influence of one leading geological process. The Auerbakh structure is a larger and more complex structure; it is characterized by a long and multistage development. According to the paleovolcanic reconstruction results, the root (focal) part of the Auerbakh structure plunged from the southeast to the northwest during the evolution of the magmatic process. Gold mineralization within the studied areas of the Northern Urals is confined to the intersections of radial faults near the centers of large concentric morphostructures.

For the first time, we apply a new approach to processing earth remote sensing data obtained by the Landsat-8 spacecraft to the central part of the Maloyralskaya zone, the Polar Urals. It consists of integrating metasomatic alteration distribution maps and lineament density patterns that were created based on the results of statistical processing of remote sensing data and the Shuttle Radar Topography Mission (SRTM) digital elevation model. This study is aimed at identifying morphological features and patterns and features of the deep structure and at identifying areas promising for the gold-polymetallic type of mineralization in the studied area. As a result of the study, it is established that areas promising for the gold–polymetallic type of mineralization in the central part of the Maloyralskaya zone are localized along transregional fault zones that intersect favorable horizons and structures and control ore mineralization and within large morphostructures complicated by radial faults of the first-order NE and NW direction with a length of up to 30 km, as well as areas with increased indices of iron oxides (II and III) and, less often, hydroxide (Al–OH and Mg–OH) and carbonate-containing minerals.

Territories of the eastern slope of the Polar Urals are promising for the identification of gold mineralization based on the materials of the multispectral satellite imagery of the Landsat 8 spacecraft—the Yun’yaginskoe ore field (Shchuch’inskaya zone), Toupugol–Khan’meyshorskiy ore district, and Manyukuyu–Vorchatinsky ore cluster (central part of the Maloural’skaya zone)—are analyzed. These areas are compared to reveal similar features of geological structure and the location of deposits and ore occurrences in the system of morphostructures, which will help to develop prospecting indicators (geological, morphological) for gold-bearing ore mineralization. It is found that prospecting for gold-ore mineralization in this area should be performed in the concentric circles of the ring structures of the second order (diameter ≥10 km) in association with subvolcanic bodies of quartz diorites/granodiorites, as well as on the periphery of the inner part of large ring structures of the first order (more than 50 km in diameter) of a complex structure with signs of “telescoping” related to intrusive formations, represented by diorites, quartz monzodiorites, and granodiorites of the final phase of intrusion. The mineralization should be localized together with areas of lineaments thickened in NW, NE and/or sublatitudinal directions and within the regional fault zones up to hundreds of kilometers in length. The mineralization is formed at the final stage of the development of volcanic structures.