Ore Minerals Research Articles

Preparation of light fraction silicate filer after the mining for the base layers’ road construction

The article main objective was eco-innovation in the field of utilization and creation of a complex waste-free technology for the separation of components during ore extraction with subsequent processing, recovery of mine tailings in combination with available energy. The article deals with the topic of production and preparation of base layers for road construction in the form of silicate filer after separation of ore mining. The chemical and mineralogical composition on the fine fraction of the separated tailings was carried out by XRD analysis, filer particle size followed up by Laser Granulometry and other comprehensive measurements and the development of basic parameters by individual standard tests. The results determined on the functional sample demonstrated that it is possible to create an almost completely waste-free technology in the field of separation of components during ore extraction and its subsequent processing and use for the base layers of linear road construction.

In situ apatite and carbonate Lu-Hf and molybdenite Re-Os geochronology for ore deposit research: Method validation and example application to Cu-Au mineralisation

The development of laser ablation inductively coupled plasma quadrupole tandem mass spectrometry (LA-ICP-Q-MS/MS) opens new opportunities to rapidly date a variety of hydrothermal minerals. Here we present in situ Lu-Hf and Re-Os dates for hydrothermal apatite and molybdenite, respectively. We further report the first in situ Lu-Hf dates for bastnäsite, dolomite, and siderite, and assess their potential for constraining ore deposit geochronology. For method validation, we report isotope-dilution Lu-Hf dates for apatite reference material Bamble-1 (1102 ± 5 Ma) and calcite reference material ME-1 (1531 ± 7 Ma), enabling improved accuracy on matrix-matched calibration for LA-ICP-MS/MS Lu-Hf dating. The new methods are applied to the Vulcan Iron-Oxide Copper-Gold (IOCG) prospect in the Olympic Cu-Au Province of South Australia. Such deposits have been difficult to accurately date, given the general lack of reliable mineral geochronometers that are cogenetic with IOCG mineralisation. Hydrothermal apatite Lu-Hf dates and molybdenite Re-Os dates demonstrate that mineralisation at Vulcan largely occurred at ca. 1.6 Ga, contemporaneous with the world class Olympic Dam deposit. Our data also indicates that the Lu-Hf system in apatite is more robust than the U-Pb system for determining the timing of primary apatite formation in an IOCG system. We further demonstrate that dolomite can retain Lu-Hf growth ages over an extended time period (>1.5 billion years), providing constraints on the timing of primary ore mineral crystallisation during brecciation and IOCG mineralisation. Finally, late Neoproterozoic (ca. 589–544 Ma) and Carboniferous (ca. 334 ± 7 Ma) Lu-Hf dates were obtained for texturally late Cu-bearing carbonate veins, illustrating that the carbonate Lu-Hf method allows direct dating of Cu remobilisation events. This has important implications for mineral exploration as the remobilised Cu may have been transferred to younger deposits hosted in Neoproterozoic sedimentary basins overlaying the Olympic IOCG province.

Влияние расстояния между выпускными выработками на потери руды от смерзания при выпуске

The paper considers the results of experimental studies of changes in the ore losses caused by congealing in the stoping zone during the drawing process in conditions of subzero temperatures in underground mining of eore deposits in the cryolithic zone, depending on the distance between the draw holes. Three series of experiments were performed using trench-shaped test benches with various distances betwen the draw holes. The distances between the access crosscuts were assumed to be 180, 200 and 220 mm, which is equal to 9, 10 and 11 m in actual conditions according to the adopted geometric scale of modeling. The results of modeling the bottom drawing in conditions of subzero temperatures, similar to the conditions of the underground ore mining in the cryolithic zone, showed that changes in the distance between the draw holes with the trench-shaped design of the bottom block have a significant impact on the extraction rates. When the distance between the draw holes is increased from 9 m to 11 m, the ore loss due to congealing during the draw phase rises from 24% to 42%. Experimental studies have shown that the increased distance between the draw holes in conditions of subzero temperatures in the bottom area leads to increased ore losses caused by congealing in the stoping area.

ASTER data processing and fusion for alteration minerals and silicification detection: Implications for cupriferous mineralization exploration in the western Anti-Atlas, Morocco

Alteration minerals and silicification are typically associated with a variety of ore mineralizations and could be detected using multispectral remote sensing sensors as indicators for mineral exploration. In this investigation, the Visible Near-Infra-Red (VNIR), Short-Wave Infra-Red (SWIR), and Thermal Infra-Red (TIR) bands of the ASTER satellite sensor derived layers were fused to detect alteration minerals and silicification in east the Kerdous inlier for cupriferous mineralization exploration. Several image processing techniques were executed in the present investigation, namely, Band Ratio (BR), Selective Principal Component Analysis (SPCA) and Constrained Energy Minimization (CEM) techniques. Initially, the BR and SPCA processing results revealed several alteration zones, including argillic, phyllic, dolomitization and silicification as well as iron oxides and hydroxides. Then, these zones were mapped at sub-pixel level using the CEM technique. Pyrophyllite, kaolinite, dolomite, illite, muscovite, montmorillonite, topaz and hematite were revealed displaying a significant distribution in relation with the eastern Amlen region lithological units and previously detected mineral potential zones using HyMap imaging spectroscopy. Mainly, a close spatial association between iron oxides and hydroxide minerals, argillic, and phyllic alteration was detected, as well as a strong silicification was detected around doleritic dykes unit in Jbel Lkest area. A weighted overlay approach was used in the integration of hydrothermal alteration minerals and silicification, which allowed the elaboration of a new mineral alteration map of study area with five alteration intensities. ASTER and the various employed processing techniques allowed a practical and cost effective mapping of alteration features, which corroborates well with field survey and X-ray diffraction analysis. Therefore, ASTER data and the employed processing techniques offers a practical approach for mineral prospection in comparable settings.

Reducing musculoskeletal disorders in iron ore mine operators: A fuzzy-based intervention approach.

This study focuses on evaluating the exposure to whole-body vibration (WBV) and association of musculoskeletal disorders (MSDs) with various risk factors among dumper operators in the mining industry. Despite the issue's significance, prior research has been limited. The study introduces a novel fuzzy-based approach for identifying, selecting, and prioritizing safety measures to mitigate MSD risks. Data collection comprised face-to-face interviews, anthropometric measurements, Rapid Upper Limb Assessment (RULA) scoring for posture assessment, and the Nordic Musculoskeletal questionnaire for assessment of MSD prevalence. Multiple linear and logistic regression models were used to analyse the contributing risk factors to MSDs and WBV exposure. These risk factors formed the basis for a practical approach to select appropriate safety measures based on fuzzy based aggregation method of expert's judgment aimed at mitigating the risk of MSDs. The results revealed that the risk factors such as poor work posture, WBV exposure and poor seat design were significantly associated with neck (adjusted odds ratio aOR = 4.81), upper limb and shoulder (aOR = 3.28), upper back (aOR = 5.09), and lower back pain (aOR = 3.67) at p < 0.05. Using these factors to formulate safety measures to reduce MSD risk, the minimization of sharp turns and abrupt changes in elevation in designing the haul roads, scheduled maintenance practices, and ergonomic seat design were found as important safety measures in this study. Our unique methodological approach in occupational health research could be highly beneficial for tailoring safety measures at the unit level with minimal effort.

Detection of malignant neoplasms in the population of an industrialized region

Introduction. Malignant neoplasms are the leading cause of the death over the world, ranking second after diseases of the circulatory system. The purpose of the investigation — to study the primary detectability, prevalence, and mortality from malignant neoplasms in the population of the industrialized developed region, propose ways of their early detection to prolong labour longevity. Materials and methods. Using the analysis of retrospective statistical data from the Federal State Statistics Service and the Novokuznetsk Branch of the Kuzbass Clinical Oncological Dispensary named after M.S. Rappoport, from 2013 to 2022 the information on the incidence of oncological diseases in whole and in specific locaion was collected. Results. In recent years, the incidence of malignant neoplasms in Russia, the Siberian Federal District, and the Kemerovo Region, among others, has been at a high level and continues to grow. Among men, lung cancer, colorectal cancer and prostate cancer take first place, and the latter has been competing for 2nd place in the structure of oncological pathology since 2020. At the same time, the gain in oncological diseases prevalence falls in the employable age (45 years and older). In addition to the commonly accepted facts about the risk of developing oncological pathology, there are more than 100 factors of the production environment classified as carcinogenic ones. In this regard, Kuzbass, as one of the most important economic regions of Russia, in which the leading role belongs to the industrial complex for mining and processing of coal, iron ores, and various non-metallic raw materials for metallurgy and the construction industry, refers to the regions unfavourable for the development of malignant neoplasms. Limitations. The limitations of the study relate to the impossibility at present to estimate the number of patients with malignant neoplasms employed in harmful labor conditions. Conclusion. As a result of analyzing own data and numerous studies, we propose screening for the most common oncological diseases (lung, prostate, and colorectal cancer) at periodic medical examinations, which will allow identifying these diseases at early stages for timely successful treatment, thereby prolonging labour longevity.

Evaluation of Ni-Cu Ore from Zapolyarnoe Based on Mineralogical and Physical Properties before and after Comminution

For the effective comminution and subsequent enrichment of mineral ores, comprehensive knowledge of their mineralogical and physical properties is required. Using an integrated methodology, this study evaluated samples of polymetallic Ni-Cu ore from Zapolyarnoe, Russia. Several analytical techniques were utilised, including optical microscopy, microindentation with Vickers geometry, the Point Load Test, and Mineral Liberation Analysis (MLA). The purpose of this study was to determine mineral associations, physical features, and enrichment during jaw crusher comminution. The acquired properties included the Point Load Strength Index, Vickers Hardness Number, and fracture toughness. The MLA method characterised seven fractions in terms of particle size distribution, degree of liberation, association, and modal mineralogy. Magnetite, pyrrhotite, pentlandite, and chalcopyrite were calculated in terms of wt% and their textural features. The enrichment of each ore phase in fractions with particle sizes smaller than 400 µm was determined. The influence of this enrichment was discovered to be correlated with various textural and structural parameters, such as intergrowth, grain size, and crack morphologies after indentations. In addition, the chromium content of magnetite contributed to an increase in the fracture toughness values. Despite the complexities involved, even limited samples of materials provide valuable insights into processing behaviour, emphasising the importance of considering mineralogical parameters in comminution studies.

Using Hg isotopes and trace elements to constrain the origin of the Ordovician Xiangquan Tl deposit, South China

Sediment-hosted stratiform sulfide (SHSS) deposits commonly contain large amounts of strategic metals, such as Tl, Hg, Cd, Ge and Ga, however, sources of these metals remain debate. Here we present new elemental and Hg isotopic data to constrain the metal sources for the Xiangquan Tl deposit (South China), a unique SHSS deposit with 250 t Tl at an average grade of 928 ppm. Stratiform pyrite orebodies are hosted in the Ordovician marine sedimentary succession of mostly limestone with minor mudstone. Pyrite, the dominant ore mineral, is rich in Hg (up to 1360 ppm). Bulk ores and pyrite separates from this deposit have significant variations of δ202Hg (−5.48 to −0.65 ‰) and Δ199Hg (−0.01 to 0.36 ‰). The Δ199Hg values are mostly positive, similar to those of seawater and marine sediments. Ore petrography, trace element enrichment coefficients, rare earth element patterns, Re-Os ages (478 ± 33 Ma) and S isotope compositions of pyrite indicate that Hg and other metals were derived from hydrothermal fluids venting at the seafloor. We suggest that the ore-forming fluids of the Xiangquan deposit were predominantly originated from large-scale circulation of evolved seawater, which leached Hg and Tl from the marine country rocks. These metal-rich fluids migrated upward, vented to the seafloor, and mixed with anoxic H2S-rich seawater to precipitate Hg- and Tl-rich pyrite. Our study highlights that the combined application of Hg isotopes and trace elements could be used to trace the sources of metals in hydrothermal ore deposits such as SHSS deposits.

Mining Charity

Scalding water, plummeting cage elevators, cave-ins, fiery explosions, toxic air. These were among the many hazards of silver ore mining on Nevada’s Comstock Lode in the late 1800s. This article explores the nature of silver mining society in the 1860s and 1870s, focusing on the dangerous conditions in which miners worked in the mineshafts that ran beneath the communities of Virginia City and Gold Hill, Nevada. The material culture and conditions of mining, the article argues, were central to determining the community’s needs and the charitable efforts mounted to address them. Philanthropic work and fundraising for a diverse set of causes—from attending to individuals’ needs to building a hospital to running an orphanage—shaped residents’ social and cultural lives, as well as the built environment in which they lived.

Black Crust from Historic Buildings as a Natural Indicator of Air Pollution: A Case Study of the Lipowiec Castle, Babice, Southern Poland

The study is focused on the analysis of black crust and soiling on the building materials of the medieval Lipowiec Castle in southern Poland. The castle was constructed using local, partly dolomitic limestones and dolomites, supplemented with other limestones and bricks, during 20th-century renovations of the castle ruins. The crust and soiling components, secondary mineral phases, and particulate matter of anthropogenic origin were analysed using Raman micro-spectroscopy (RS) and scanning electron microscopy coupled with energy-dispersive spectrometry (SEM-EDS). The crust, mostly composed of gypsum and other sulphate phases, was found to contain carbonaceous matter, spherical Si-Al glass particles, and iron oxides, with admixtures of other elements, including heavy metals, as well as irregularly shaped particles containing various metals. These components reflect the air pollution in the region, related to the combustion of solid fuels in both industrial power plants and local domestic furnaces, Zn-Pb ore mining (operational until 2021), and smelting in the neighbouring industrial centre. Despite its location in a rural area, the castle has been exposed to pollution for an extended period due to its proximity to large industrial centres. Therefore, the crust analysed may serve as an environmental indicator of the nature of the air pollution in the region.

Innovative technology for mining parallel superimposed inclined tabular deposits

Ore deposits are often parallel superimposed inclined tabular ones with waste rock inclusions between ore beds. The present research aims to develop an innovative safe and efficient technology to reduce the cost of waste rock transportation outside the stoping block and provide a rational flowsheet for mining superimposed beds with original structural elements. The paper proposes a new technological flowsheet for mining superimposed deposits with disposal of waste rocks occurring between beds in previously prepared rooms and establishes new dependencies of room dimensions on the volume of rocks to be disposed. The research results enable expansion of the scope of employment of room mining systems and significant reduction in costs in the working area. The efficiency of ore mining is achieved by creating room crowns from unmined interbedded rocks, disposing broken waste rocks in worked-out spaces and rationally mining the deposits. Implementation of the proposed technology enables reduction of the cost of mining ore from parallel superimposed inclined tabular deposits.

Prediction of the mineral components spatial distribution in tailings ferruginous quartzite enrichments

In Ukraine, a significant mass of potential man-made deposits is represented by waste from ferruginous quartzite enrichment. The mineral mass of such deposits is mixture of iron-containing minerals (magnetite, ilmenite) and quartz. The M.S. Poliakov Institute of Geotechnical Mechanics has developed a new methodology for the mineral components spatial distribution predicting in tailings of ferruginous quartzite enrichment. It includes the fractional and mineralogical composition of the samples study by optical method, and spatial useful components distribution of prognostication in waste and predictive plans construction for the useful components spatial placement. A previously unknown pattern of changes in mineral composition of wastes from mining ore production was revealed which caused by the turbulent transportation mode and waste deposition on the tailing (potential man-made deposit) area. This regularity arises from the fact that with decrease in the size of the mineral components particles with size of 0-200 microns, the share of the magnetic mineral magnetite increases linearly and, accordingly, the share of the non-magnetic mineral quartz decreases. The obtained new properties of man-made deposits from the waste (tailings) can be used in creation of resource-saving technology for the iron ore man-made raw materials processing and to determine their suitability for mining.

Mining and processing of chrysotile-bearing ore

Mining and processing of chrysotile-bearing ore

Production of mineral wool from by-products of chrysotile ore mining

Production of mineral wool from by-products of chrysotile ore mining

Constraints on Ore Genesis from Trace Ore Mineralogy: A New Occurrence of Kupčíkite and Paděraite from the Zhibula Cu Skarn Deposit, Southern Tibet

Mineral assemblages containing Cu-Bi sulfosalts, Bi chalcogenides, and Ag-(Au) tellurides have been identified in the mid-Miocene Zhibula Cu skarn deposit, Gangdese Belt, southern Tibet. Different mineral assemblages from three locations in the deposit, including proximal massive garnet skarn, proximal retrogressed pyroxene-dominant skarn in contact with marble, and distal banded garnet–pyroxene skarn hosted in marble, are studied to constrain the evolution of the mineralization. Hypogene bornite contains elevated Bi (mean 6.73 wt.%) and co-exists in proximal andradite skarn with a second bornite with far lower Bi content, carrollite, Au-Ag tellurides (hessite, petzite), and wittichenite. This assemblage indicates formation at relatively high temperatures (&gt;400 °C) and high fS2 and fTe2 during prograde-stage mineralization. Assemblages of Bi sulfosalts (wittichenite, aikinite, kupčíkite, and paděraite) and bismuth chalcogenides (e.g., tetradymite) in proximal pyroxene skarn are also indicative of formation at relatively high temperatures, but at relatively lower fTe2 and fS2 conditions. Within the reduced distal skarn (chalcopyrite–pyrrhotite-bearing) in marble, cobalt, and nickel occur as discrete minerals: cobaltite, melonite and cobaltic pentlandite. The trace ore mineral signature of the Zhibula skarn and the distributions of precious and critical trace elements such as Ag, Au, Co, Te, Se, and Bi support an evolving magmatic–hydrothermal system in which different parts of the deposit each define ore formation at distinct local physicochemical conditions. This is the first report of kupčíkite and paděraite from a Chinese location. Their compositions are comparable to other occurrences, but conspicuously, they do not form nanoscale intergrowths with one another.

Potentially Harmful Elements (As, Sb, Cd, Pb) in Soil Polluted by Historical Smelting Operation in the Upper Silesian Area (Southern Poland)

This study aimed at determining the concentration and possibility of migration of potentially harmful elements (PHEs) in soils and mining and metallurgical waste in the Silesian-Cracow region. Our research was carried out in selected locations of Ruda Śląska, Świętochłowice, Bytom, and in the Olkusz region (Bukowno) in southern Poland. The concentrations of metals (e.g., Ag, Ba, Ca, Cd, Cu, Fe, Mg, Mn, Pb, Sr, Zn), metalloids (As, Sb), and sulphur were determined in 33 soil samples (with a depth range of 0.0–0.3 m) and 12 slag samples. These studies show an increased concentration of metals, metalloids, and sulphur, exceeding the level of regional geochemical background. The research results indicate that the degree of the chemical transformation of soils in the analysed regions of Ruda Śląska, Bytom, and Bukowno is advanced. This highlights the high concentrations of most metals, i.e., arsenic, antimony, and sulphur, in the surface layer of soils (topsoil) due to historic Zn-Pb ore mining and Zn and Fe metallurgy. The presence of both primary and secondary metal sulphides, sulphates, carbonates, oxides/hydroxides, silicates, and aluminosilicates was found in the mineral composition of soils and slags.

Rare metal concentration features at a caldera type deposit in the Miocene-Quaternary boron-lithium province of North America. Search for analogues

The fact that lithium has a wide range of applications in many fields including the production of lithium-ion batteries determines an increased interest in lithium mining. The most common types of lithium raw material sources are underground brines, saline lakes (“salars”), and ore minerals. In 2021, the first and unique deposit of lithium clays was discovered in the McDermitt caldera (Nevada, USA). Its resources are estimated at 13.7 million tons of lithium carbonate with the lithium concentration of 2231 mg/l. The uniqueness of this deposit raises the interest in the formation of model ideas about lithiumclay genesis to search for analogous deposits and explore them. The purpose of the article is to provide an overview of the geological structure and describe the main development periods of the McDermitt caldera. The authors also characterize the potential sources of lithium (felsic igneous rocks and hydrothermal fluids), migration paths of lithium-bearing brines as well as the formation mechanism of clays with a high lithium content (hectorite, illite and smectite). A generalized formation model of this type of deposits is proposed. Particular attention is paid to the role of hydrothermal fluids as a potential additional source of lithium “supply” to the caldera basin. Key criteria characteristic of industrial accumulations of lithium of this type have been formed in order to explore and identify analogous deposits. In conclusion, the authors put forward a hypothesis about the presence of deposits that are analogous to the Thacker Pass in the McDermitt caldera in the lithium province on the Altiplano-Puna plateau in one of the calderas of the Altiplano-Puna volcanic complex, and in Eastern Kamchatka.

Unravelling the effects of magmatic fractionation, fluid phase separation and dilution on the composition of magmatic-hydrothermal fluids of the Cornubian Batholith (SW England)

The compositional evolution of magmatic-hydrothermal fluids from the SnW mineralized Cornubian batholith was investigated via in situ fluid inclusion LA-ICP-MS microanalysis and reveals a large degree of variation between intrusive stages and at the sample scale, with complexities due to superposition of several mechanisms affecting fluids chemistry during the protracted evolution of the batholith. Despite large ranges of salinities (from <1 wt% to 48 wt% NaCleq.), the effects of individual processes such as magmatic differentiation, fluid saturation and boiling, fluid mixing and dilution can all be discerned on the basis of fluid inclusion trace element geochemistry combined with detailed petrography and microthermometry.In all samples, different fluid types (aqueous liquid-rich, vapor-rich and brine inclusions) were identified in variable proportions and microthermometry revealed complex temporal trends. Granite-related samples from the G5 intrusive stage are characterized by intermediate density fluids undergoing magmatic fractionation under pressure conditions above 1.5 kbar, indicated by successively decreasing fluid salinities with concomitant increases in Li, B, Rb and Cs concentrations. The latter two elements later strongly partitioned in the brine phase upon boiling, together with most of the other Cl-complexing elements (e.g., Fe, Mn, Pb, Zn). Those brines subsequently underwent progressive dilution with meteoric waters that caused a decrease in the concentration of all elements (besides B) and homogenization temperatures. In G3 granite from Dartmoor, on the other hand, brine inclusions represent the earliest fluid type while intermediate density fluids are absent, and a large salinity range in the fluid inclusion record associated with a decrease in homogenization temperatures represents their progressive dilution with meteoric fluid. The lack of intermediate density fluids at Dartmoor indicates fluid exsolution at relatively low pressures resulting in immediate phase separation into brine and vapor.All studied samples associated with ore mineralization display only the trend of dilution of high-salinity magmatic fluids. Their transition metal contents (e.g. Fe, Mn, Pb and Zn) show the expected positive correlation with salinity of the fluids. Conversely, the compositional trends observed for Sn and particularly W are more enigmatic, as they do not appear to significantly fractionate during most of the physicochemical processes outlined above and appear to be unrelated to fluid salinity, opposite of what would be expected for Sn as it is dominantly transported in Cl-complexes.This study highlights the key advantages of high-resolution geochemical fluid inclusion studies in discerning a variety of magmatic and post-magmatic processes in fluids in comparison to bulk fluid inclusion techniques or more simplistic fluid inclusions studies which might overlook important aspects of the typically complex history of fluids evolution in magmatic-hydrothermal systems.

Material composition of copper slag of the Almalyk copper-smelting plant (Uzbekistan)

Relevance. Copper production is accompanied by release of a large volume of slag. Today, huge quantities of copper slags have accumulated all over the world, in which the copper content is even greater than that in original ores. The slags that result from the smelting of ores and concentrates of both ferrous and non-ferrous metals, together with other metallurgical wastes such as tailings, are increasingly the subject of significant environmental controversy. The only way to reduce the negative impact of slag waste on the environment can be their disposal, by complex extraction of valuable components from them and further use of slag waste for construction purposes. In addition to the main component of copper, copper slags contain elevated contents of gold, silver, zinc, iron, etc. The form of finding valuable metals such as iron, copper, lead and zinc in copper slags is complex. A detailed study of the mineral composition of slags is used in development of an effective technology for processing slags. Aim. To study mineral composition of copper slags, the form of finding valuable components. Object. Copper slag waste from the copper-smelting plant of the Almalyk MMC. Methods. Chemical composition of copper slags was established by phase analysis, atomic absorption, X-ray fluorescence research methods. Mineral composition of the ores was established as a result of complex studies, including: optical microscopy in transmitted and reflected light, X-ray diffraction, microprobe studies and electron microscopy. Results. Copper content in composition of copper slag samples is higher than in copper ores and it is 0.77–0.97%. In addition to copper, copper slags contain elevated contents of a complex of metals (g/t): Au – 0.17–0.26; Ag 8.42–10.64, Zn 4.288–10216, Pb – 2014-3360. Ferrous silicates (fayalite, ferrosillite), vitreous mass of ferruginous-silicate composition predominate in the composition of copper slags. Ore minerals are mainly represented by magnetite. The mineral content is approximately 10–15%. Among сopper sulfides minerals bornite, chalcocite, less often cubanite, chalcopyrite, covellite sharply predominate. Cuprite is observed in small amounts, and native copper is metallic. The mineral form of finding molybdenum is molybdenite. Among the native silver minerals, native silver was found in association with lead minerals. Gold is included in the composition of native copper and chalcocite as an impurity and passes into copper concentrate during processing slags.

Geology and ore fluids geochemistry of the Hamzeh–Gharanin orogenic gold deposit, NW Iran

The Hamzeh–Gharanin gold deposit (HGD) is located in the Qolqoleh–Kasnazan shear zone in the northwest of Sanandaj–Sirjan Zone (SSZ) and 40 km SW of Saqez. The main rock units are an assemblage of the Precambrian metasedimentary (pelitic) rocks and the Cretaceous phyllite associated with marble interlayers. The post–Cretaceous intrusive granitoids with NW–SE trends intruded within these two units. Mineralization occurs mainly within the NE–SW extensional veines and veinlets in proto–mylonitic, mylonitic and ultra–mylonitic rocks. Hydrothermal alterations consist of sericitization, carbonatization, silicification and chloritization. The main ore minerals include pyrite, chalcopyrite, arsenopyrite, pyrrhotite, sphalerite, galena, gold, magnetite and hematite. The fluid inclusions study from quartz minerals associated with the mineralization shows four different phases: single vapor phase (V; type I), single liquid phase (L; type II), liquid–vapor biphasic (LV; type III) and three phases (LLV; type IV). Microthermometric studies were performed on types III and IV of fluid inclusions. Homogenization temperatures (Th) for Types III and IV inclusions vary between 138 and 310 °C (mean 230 °C) and 250–335 °C (mean 300 °C) and their salinity varies between 0.52 and 13.87 and 4.79 to 9.58 (wt% NaCl), respectively. Moreover, the density of Types III and IV inclusions vary from 0.71 to 0.927 g/cm3 and 0.700–0.870 g/cm3, respectively. The oxygen (in quartz: 4.58–7.80 ‰; mean 5.82 ‰) and δ34S (in pyrite: 5.54–6.28 ‰; mean 5.91‰) isotope compositions of the mineralizing fluids indicate an insignificant meteoric water input during hydrothermal evolution and a magmatic origin of sulfur in the deposit which is broadly similar to those of orogenic gold deposits worldwide.