Gold Industry Research Articles

Use of Digital Elevation Models in Metallogenic Investigations on the Example of the Central Part of the Lower Amur Province

Abstract —The digital elevation model (SRTM03) of the central part of the Lower Amur province is analyzed. The Limuri–Amgun ring structure is identified on the basis of a set of features, and it is also the location of the Pilda–Limuri and Kherpuchin–V’yunsky gold-ore regions, as well as the Albazino deposit, known for large industrial gold deposits and many small deposits and ore occurrences. The distribution of linear and ring elements of the relief is analyzed and geologically interpreted, and its spatial relationship with gold deposits and ore occurrences is shown. The relationship between the morphological severity of the ring structure and the deep structure of the region is shown. It is revealed that the structure is magmatic and characterized by a high concentration of intrusive bodies. According to the reference data on the age and composition of the igneous complexes of the region, the formation of the ring structure is associated with the processes of formation and transformation of the Earth’s crust and upper mantle during the end of the Late Cretaceous and the onset of the Paleocene in a suprasubduction geodynamic setting.

Efficient and selective gold recovery from e-waste by imidazolium-based poly(ionic liquid)s

Recycling gold from e-waste is not only beneficial to environmental protection, but also to resource sustainability. However, it remains a great challenge due to the limitations of high cost, lengthy balance process and the interference of coexisting metals. Herein, a family of low-cost, nitrogen-rich content and acid-stable imidazolium-based poly(ionic liquid)s, designated as P(nDVB-mVBIMCl)s, were synthesized for recovery of gold from e-waste. The obtained P(2DVB-8VBIMCl)s achieves outstanding adsorption capacity (820.5 mg·g−1) and rapid equilibrium time (15 min) and satisfactory reusability (more than 8 cycles). XPS, EDS and ion chromatography revealed that the excellent adsorption performance was attributed to synergistic effect of ion exchange and chemical reduction. In addition, the P(2DVB-8VBIMCl)s showed excellent selectivity for gold in actual e-waste leaching solution, exhibited satisfactory selectivity coefficient for Fe3+ (1.46 × 104) and Ni2+ (1.12 × 104), obtaining 23.4 karat high-purity gold after calcination. In addition, the P(2DVB-8VBIMCl)s shows its good economic feasibility. Overall, this work provides a feasible adsorbent, which becomes a promising candidate for industrial gold recovery from e-waste.

Evaluation of Metal Contamination of Sediments around an Industrial Gold Mine in Côte d’Ivoire: The Example of Arsenic

Evaluation of Metal Contamination of Sediments around an Industrial Gold Mine in Côte d’Ivoire: The Example of Arsenic

Gestión de recursos naturales mediante el análisis sector turístico y minero para el logro del equilibrio ecológico y la sostenibilidad en la provincia El Oro

The article makes an analysis of the tourism and mining sectors of the "El Oro" province and the management of natural resources can improve the ecological balance and sustainability in the region. The text demonstrates that in order to meet the needs of present and future generations, the importance of a harmonious relationship between the elements of social, political and environmental sustainability is highlighted. The tourist area of El Oro in Ecuador has unique natural resources: its beaches, mangroves, mountains and nature reserves, lovers of nature and ecotourism will find unforgettable experiences. The importance of a harmonious relationship between the elements of social, political and environmental sustainability is highlighted to meet the needs of present and future generations. Ecuador has great natural wealth, especially fresh water, which is considered one of the most abundant in the world, but the lack of knowledge and appreciation of these can lead to poor management and a negative impact on the environment and the economy. Mineral resources related to the gold industry in Ecuador were analyzed, examining their relevance, environmental effects and future prospects. Measures are proposed to promote sustainable tourism and the challenges facing the management of natural resources in the region are mentioned, in order to achieve a sustainable and balanced development in the province.

Behavioral and biochemical patterns in the Andean highland macroinvertebrate Nectopsyche sp. after chronic mercury exposure

Environmental pollution by mercury (Hg) is of particular interest in Latin American countries like Ecuador, where artisanal and industrial gold mining has widely expanded. However, classic assessments, either based on water parameters or bioindicators, are not always effective in determining the effect of this type of pollutant on the ecological quality of the rivers. This study analyzed the behavioral and biochemical responses in benthic macroinvertebrate Nectopsyche sp. after sub-lethal Hg exposure emulating the maximum limits allowed by the current legislation in Ecuador (0.0002 mg L−1). Behavioral changes were significant, with an average decrease in the movement (measured as the number of strokes per 15 s of larvae) after 6 days of exposure to the maximum limit concentration of Hg. Furthermore, the antioxidant enzyme Glutathione S-Transferase activity significantly increased when exposed for 7 days to 0.0002 mg L−1 of Hg concentration. These results preliminarily proved that behavioral and biochemical patterns could function as biomarkers that efficiently identify ecological impairment caused by Hg, which would otherwise be neglected by a purely chemical-based or biomonitoring based on the presence/absence of macroinvertebrates type of assessment. Moreover, we demonstrate that the current limits allowed can impair aquatic life.

How are Russia’s industries adapting to Western economic pressure? The case of gold

ABSTRACT In this article the author draws on materials including government policies, corporate and media reports, and analysis of industry trends, to describe the development of Russia’s gold industry since 2000. The growth of the sector exemplifies the Putin administration’s determination to increase production and exports in the natural resource sectors, and offers further evidence of how Russia’s ‘limited access’ system of political economy functions. The author then examines how the industry has responded to Western pressure since the invasion of Ukraine in February 2022. This provides insight in to how the sector is faring, how it is re-orienting to non-European markets, and the practical measures corporations have taken to evade sanctions and find new suppliers. The author argues that if this industry, and other metals and mining industries, can succeed in these efforts, they will provide a boost to Russia’s effort to sure up essential export revenues.

A clean and efficient innovative technology for refractory sulfide gold ore: In situ gold extraction via self-generated thiosulfate

Green non-toxic extracting gold from refractory sulfide gold ore using thiosulfate is an essential guarantee for the sustainable development of the gold industry. However, there are many bottlenecks, including environmental pollution from traditional pretreatment of sulfide gold ore and high consumption of chemical thiosulfate. Herein, a clean and efficient innovative technology for the comprehensive utilization of refractory sulfide gold ore (high sulfur and high arsenic) was first proposed. For high arsenic sulfide gold ore, a sufficient sulfur source (addition of pyrite or sulfur) could be supplemented, and then thermal activation pretreatment for thiosulfate generation. This alternative technology can prevent the volatilization of hazardous gases (SO2 and As2O3) and instead collect them as less harmful solids (S8 and As2S3). Moreover, thermal activation pretreatment of this sulfide gold ore significantly enhances the oxidation capacity and results in the generation of sufficient thiosulfate (286 mM). The pretreatment also breaks down the sulfide inclusions to expose the encapsulated gold, which can be in situ extracted via self-generated thiosulfate. As a result, a gold extraction rate of 80.2% was achieved for this refractory sulfide gold ore without the addition of chemical thiosulfate. This innovative technology is of high academic and industrial interest, addressing the high thiosulfate consumption and promoting the industrialization of green gold extraction from refractory sulfide gold ore.

ETHICAL ELEGANCE TO TIMELESS TREASURES: DECODING THE ALLURE OF MODERN JEWELLERY TRENDS & TOP BRANDED SELLERS AMONG TODAY'S FASHION FORWARD WORKING WOMEN

India is getting more modern as portrayed in its big banners by one of leading multi-brand retail seller, ‘Big Bazaar’. Jewellery market is not an exception to this trend of getting more trendy and awesome. Indian working women wearing western outfits are lured towards light weight branded jewellery which suits the attire, enhancing overall look and beauty. Fashion brands like Mia by Tanishq, ORRA, Goenka India, Amrapali are renowned globally for their antique, glittering unique piece of designs. This is an attempt to overview the ever growing gold industry with changing demands and market needs considering working fashion-forward women in cities of India.

Role of Integrated Magnetics and Geology in Tracking and Exploring Complex Structures Controlling Gold Mineralization. Example from the Fawakheir-Atalla Gold Prospects, Eastern Desert, Egypt

Gold mineralisation is spatially and chronologically correlated with fault/shear zones in many of the world-class gold mines. Hence, the indirect exploration for Au mineralisation is linked with shearing and complex structures in many areas. Hence, in general, the need for a rapid, effective and new technology for gold exploration that reflects the structure set-up, shear zones, faults and related structural elements is crucial in the gold industry. In this article, we present an example of an integrated approach to gold exploration in the Fawakheir-Attala gold mining prospect in the eastern desert of Egypt. Remote sensing is used to test for rock differentiation; intensive field geological investigations were conducted along several traverses. Petrographic and geochemical analysis of selected samples confirmed Au content in some localities. Moreover, magnetic methods are used extensively (either aeromagnetic or measured land profiles) to investigate the magnetic signature of the different reported rock units and their relationship with gold occurrences and deposits. Normalised source strength transformation, magnitude magnetic transforms and subsurface modelling are used to explore the inherent relation between the surface and subsurface magnetic susceptibilities. The magnetic signature of the talc-carbonate rocks is determined. The gradational contact against the serpentinite is explained. Because three current Au mines are associated with contacts/fractures, the clear relation between the contacts/fractures and the magnetic data and the comparison with the contact occurrence density COD (heat) magnetic filtered map, the present analysis workflow can now be used to suggest new locations for Au occurrences.

Alexander I. Pogrebetsky's Research Note on the State and Prospects of the Bodaybinsky District Amidst the Civil War

The research note published below is a fairly complete description of the economic status of the Bodaybinsky gold mining district. The note was prepared in the summer of 1919 in the conditions of political instability and economic crisis. Given the remoteness of the Bodaybinsky district and the lack of reliable information about its economic situation, this note was a valuable source for studying the affairs in this important for the economy of the Irkutsk Province area and the possible prospects for its restoration. Its task was to assess the economy and finances of the district in order to open a representative office of the Irkutsk branch of the Moscow People's Bank in it. This research note was not published and remained out of sight of researchers studying the history of the gold industry. Its author was Alexander I. Pogrebetsky, an active member of cooperative movement and an economist, later known as a researcher in the history of money circulation and finance in Siberia and the Far East.

A CNN-Based Wearable System for Driver Drowsiness Detection

Drowsiness poses a serious challenge to road safety and various in-cabin sensing technologies have been experimented with to monitor driver alertness. Cameras offer a convenient means for contactless sensing, but they may violate user privacy and require complex algorithms to accommodate user (e.g., sunglasses) and environmental (e.g., lighting conditions) constraints. This paper presents a lightweight convolution neural network that measures eye closure based on eye images captured by a wearable glass prototype, which features a hot mirror-based design that allows the camera to be installed on the glass temples. The experimental results showed that the wearable glass prototype, with the neural network in its core, was highly effective in detecting eye blinks. The blink rate derived from the glass output was highly consistent with an industrial gold standard EyeLink eye-tracker. As eye blink characteristics are sensitive measures of driver drowsiness, the glass prototype and the lightweight neural network presented in this paper would provide a computationally efficient yet viable solution for real-world applications.

Book notice: Gold Laundering: The Dirty Secrets of the Gold Trade — And How to Clean Up

For centuries, humankind has been fascinated by the glitz and glamour of gold. With its multiple uses, ranging from components in mobile phones to medicine, gold remains one of the oldest and most sought after commodities. Regrettably, much like diamonds, this precious metal is mired in conflict. Gold gives rise to significant challenges in various sectors, from mining through industrial applications to retailing. Gold Laundering by Mark Pieth provides us with edifying insights into both the glittering world of the gold industry and the horrific problems caused by the gold trade.

Quantification of Chemical Composition Distribution of Polyolefin Materials for Improved Accuracy and Speed

Crystallization-based separation techniques are widely used for chemical composition distribution (CCD, also often referred as short chain branching distribution SCBD) measurement in the polyolefin industry, in which CCD is among the most critical structural parameters to define their properties and applications. The desire to improve the sample throughput rate by shortening the analysis time in the current CCD techniques would normally sacrifice measurement accuracy due to the cocrystallization phenomena, in which the polymer chains with similar molecular architectures will cocrystallize or coelute enigmatically in the CCD analysis. Herein, we reported the investigation by exploring various separation packing materials on the cocrystallization phenomena. In comparison with the commercially available Crystallization Elution Fractionation (CEF) technique, an improved technique for CCD measurement (iCCD) was developed using the columns packed with gold-coated nickel substrate or spherical gold particles with or without the dynamic cooling process. With iCCD, it was observed with equivalent cocrystallization degree to the industrial gold standard benchmark Wild-TREF method but with over 70+ times improved sample throughput rate (62 vs 4500 min). The experimental CCD chromatogram for a polyolefin blend similarly assembled to the mathematically constructed result further demonstrated the minimized cocrystallization and measurement accuracy in the iCCD method. In addition, the superior mechanical properties of gold-coated nickel particles enabled the long-term robustness and enhanced measurement precision of the iCCD technique during the repeated thermal treatment cycles and pressure variations.

The Night Trains: Moving Mozambican Miners to and from South Africa, 1902–1955

The Night Trains: Moving Mozambican Miners to and from South Africa, 1902–1955

A developing novel alternative bio-oxidation approach to treat low-grade refractory sulfide ores at circumneutral pH

The extensive neutralization required in acidic bio-oxidation, a conventional pretreatment for low-grade refractory matrices in the gold industry, constitutes one of the principal drawbacks due to the large volume of waste streams. Performing an oxidative pretreatment at circumneutral pH with an in-situ neutralization would avoid the production of undesirable waste, causing potential economic and environmental advantages. For the first time, this investigation evaluates a novel process involving a biological oxidative pretreatment for low-grade refractory ore using two biosafety level 1 neutrophilic microorganisms encompassing Thiobacillus thioparus and Starkeya novella at near-neutral pH. Optimal bacterial growth conditions were determined regarding the culture medium and initial energy source using UV-visible and manual cell counting (cells/mL). Thereafter, biological oxidation of different matrices, including first elemental sulfur and subsequently a refractory sulfidic ore, was evaluated in batch flask cultures and then scaled up into a bioreactor using optimal experimental conditions. Results revealed that culture media containing ca. 4.5 and ca. 0.9 g/L thiosulfate favored biological oxidation of the refractory sulfidic ore using T. Thioparus and S. Novella, respectively, which led to corresponding sulfide oxidation of 27 and 14% within 10 days, comparable to reported studies. The biological action was confirmed by C/S detector and SEM technique of pre- and post-pretreatment residues. Overall, this research is a step forward to advance the understanding of a biological pretreatment out of the highly acidic pH range, promoting the view of a net-zero target by potentially reducing the production of more significant waste streams compared to conventional operations.

Biomaterials for artificial knee joint replacement: a review

Human knee works under lubrication conditions that are characterised as boundary or mixed lubrication. In these situations, the joint suffers from starved lubrication provided by the synovial fluid. Over an extended period of time, this starved lubrication causes excessive wear and leads to osteoarthritis. Biomedical implants are gaining increasing attention nowadays to improve the working lifespan of artificial implants like hip and knee joints. This stems from the fact that friction and wear are the key factors affecting the life of artificial joints. In this review, we discuss the processes affecting the normal functioning of the joint. In this model, we also discuss the materials used for the orthopaedic industry and the problems which lead to the failure of the same. The possibilities of improving the life span of ultra-high molecular weight polyethylene (UHMWPE) are also discussed as UHMWPE is the gold in the orthopaedic industry.

Assessment of Soil Contamination and Human Health Risk around an Industrial Gold Mine in Côte d’Ivoire: The Case of Arsenic

Assessment of Soil Contamination and Human Health Risk around an Industrial Gold Mine in Côte d’Ivoire: The Case of Arsenic

Portfolio Optimization among Luxury Goods, New Energy, Web 3.0 Industries and Gold

This paper aims to discuss optimal portfolio construction with assets among luxury goods, new energy, web 3.0, and gold industries, with the hope of providing insights into the investigation of the relationships between those industries and their feasibility in the process of portfolio optimization. Based on accessible data from Yahoo Finance, this paper first discusses mean-variance analysis with a focus on the return data of the chosen assets, then utilizes Fama-French three factor model to run a portfolio optimization among those assets with core indexes being the maximization of Sharpe Ratio and the minimization of variance. As a result, two portfolios with different weights assigned to each asset are generated and they could be a good indication of the relationships between the discussed industries and their connections under investment scenario, and therefore may provide valuable information to the related financial market investors.

Transformer oil vs. kerosene: Selective collectors for C-matter flotation from a double refractory gold ore

A study was performed to evaluate the effect of collector type on the flotation of carbonaceous matter (C-matter) from a refractory gold ore, with the objective of improving gold recovery through separate treatment of the flotation concentrate and tailings. Transformer oil and kerosene were investigated as C-matter collectors in a single rougher flotation stage. Both collectors were tested at varying dosages, with emulsification (‘emulsion’) and without emulsification (‘normal’) using a 2-level full factorial Design of Experiments (DOE). The kerosene emulsion at 500 g t-1 resulted in the highest C-matter recovery (66%) with a C-matter grade of 4.38% (∼2.4 times upgrade), showing improved flotation performance compared with normal kerosene. Normal transformer oil at 500 g t-1 resulted in a C-matter grade of 4.65% with 61% C-matter recovery, and emulsion of transformer oil had little effect on flotation performance. The finer droplet size in the kerosene emulsion resulted in a faster flotation rate, leading to higher C-matter recovery than both transformer and normal kerosene. However, FT-IR analysis demonstrated that the interaction of transformer oil with C-matter was different than kerosene, forming a stronger attachment to C-matter surfaces. The flotation concentrate obtained under the most promising conditions (kerosene emulsion 500 g t-1) contained 51 % of gold, while 49 % of the gold reported to the flotation tailings. The gold recovery models predicted that gold recovery from (1) roasting/cyanidation of the flotation concentrate and, (2) pressure oxidation/thiosulfate leaching of the flotation tailings, has the potential to improve the overall gold recovery from 44% to 60% (compared with pressure oxidation/thiosulfate leaching only). In its first application as a collector in C-matter flotation, transformer oil showed great potential despite the highly disseminated, complex nature of the ore. The results suggest that transformer oil may be applicable in other flotation systems, beyond the gold industry, including agglomerate flotation and the flotation of carbonaceous battery materials, such as graphite, from both primary and secondary resources.

English

Since the Minamata conference, the scientific and professional worlds (gold industry, metal extraction, health) have come together to conduct research and raise awareness of the effects of mercury (Hg) in the environment, particularly on public health. Africa has not remained on the sidelines of these events, which have a planetary scope due to the long-range transport of various anthropogenic and natural sources of mercury. Since then, scientific data has been produced both in Africa and other continents in the world on the knowledge of the properties of mercury (Hg) as a poison that can migrate through all the links in the food chain. This scientific article is an analysis of mercury (Hg), its sources, its distribution, its health and environmental impacts (terrestrial, aquatic, atmospheric ecosystems, etc.) in Africa. It also aims to present the recent development in this field in the form of a general analysis and to present the measures taken at the political level to control mercury flows in developing countries while highlighting the shortcomings of these policies at the national level in some African countries. Keys words: Mercury, pollution, anthropogenic sources, health effects, Africa.