Objective method for analysis of mineral resources supply on the example of Russia

A forecast of nonfuel mineral production in Russia is considered, based on the integration of the expected life of specific deposits currently exploited and developed. It is shown that mineral safety is fully ensured for copper, nickel, lead, tungsten and tin, whose reserves are sufficient for their extraction, at least at the current level, for 40–50 years and there are real prospects for its significant growth. The sufficiency of other minerals is much lower: for molybdenum and chromium, it is limited to about 30 years, and the extraction of zinc and uranium in Russia may significantly decrease in 20 years. The situation is more difficult with the most liquid solid minerals, like gold and diamonds. The commissioning of mining enterprises at the developed gold deposits can ensure a rapid growth in the production of the precious metal in the coming years. However, at the beginning of the next decade, the resource base depletion of the Olimpiada field and a number of other exploited deposits is predicted. The projects currently implemented for the development of new fields do not compensate for the lost capacity. This may account for a long-term (until the beginning of the 2050s) decline in the Russian gold production, which may be halved against the current level by the end of this period. Such a scenario can only be avoided with the intensification of geological exploration in the coming years. The earlier decrease in the number of diamonds mined in Russia, associated with the depletion of reserves of exploited pipes, is predicted (since 2025). Unless new deposits are discovered and developed, the domestic production of precious stones will steadily decline and, in the 2040s, may be reduced fourfold.

Social economic feasibility of community’s gold mining in Kertajaya Village, Sukabumi Regency, West Java, Indonesia

Many studies have stated that Community Gold Mining (CGM) activities are considered as poor and unqualified as a profession. CGM is also believed unfeasible for business, and has less impact to state’s economic system. In general, the mainstream theories believed that CGM is unsustainable. But in fact, informal CGM activities still exist everywhere. Is CGM really unsustainable? Is CGM not proper enough to be officially supported by the state? This paper discusses and examines the practice of CGM. The research location was in Kertajaya Village, Sukabumi Regency, West Java, Indonesia. There are thousands of local people working informally as CGM miners, with gold processing units Glundung/Tubes: Trommel Mercury (TM) method. 6 components of the Gold Production System were being discussed along with its their production costs. The observation was implied for TM processing units, carried out during 2018 - 2019. The supporting data were taken from CGM site: Cijiwa Block, from 2013 to 2017. The results: CGM business in research location is feasible enough, also has high economic potency for state’s taxation. Community’s Miner is qualifying as a profession, since the miner’s income exceeds the local minimum wage. Apart from the fact that the miners still use mercury, those facts show local CGM activity can be sustained.

Gold surge will boost Bolivian exports

Significance So far this year, gold sales to India have seen that country displace Brazil as Bolivia’s most important commercial partner. While providing employment for workers in the sector, gold production does little to boost fiscal income. It also has major, negative environmental impacts. Impacts Attempts to regulate gold production may exacerbate violent responses. Cooperatives will continue to resist attempts to regulate them and sell gold through the central bank. International criminal activity may be increasingly drawn to Bolivian gold production.

Increasing gold recovery from poor ore using gravity

The article discusses the issues of increasing the efficiency of extraction of gold-bearing ores from poor ores using gravity using combined geotechnologies at the Sigiri mine (Republic of Guinea). Gravity Recoverable Gold (GRG) is defined as gold present in a particle in sufficient quantities to be selectively recovered from waste rock by gravity methods. Since Guinea is one of the ten leaders among the countries of the African continent in terms of gold reserves (2019 — 700,000 tons), it should be taken into account that the complex of measures for ore processing includes crushing modules interconnected during the technological process, grinding-gravity module, flotation module and metallurgical a module that affects the solution of the problem of integrated development of subsoil in the generally accepted understanding and this is the maximum extraction of recorded reserves from the subsoil and useful components from mined ore. The author presents the influence of the centrifugal concentrator Nelson (Knelson) on increasing the degree of gold recovery from gold-bearing poor ores under high climatic conditions. Increase in gold production by the GRG test method due to the destruction of the ore structure and a significant decrease in density, as well as an increase in the opening of minerals using gravity up to 63 %. Thus, the optimization is classified as medium-coarse gold.

Gold production in the Russian Federation: The analysis and forecast

Subject. The article discusses possible lines for improving the methodological framework of the long-term economic forecast of gold production in the Russian Federation, relying upon the mathematical apparatus of econometric models. Objectives. We devise an economic-mathematical model for predicting the gold production with respect to the specifics of the economic development in Russia’s gold mining industry. Methods. The study is based in the correlation and regression methods for analyzing publicly available statistical data on the gold market. The least square method is taken as the methodological approach to designing the economic-mathematical model for forecasting. Results. Each gold deposit is found to be distinctive, having its own qualities, which seriously differ from those of other gold deposit. As a result of the analysis, we discovered key factors, which significantly influence the gold production, such as demand and price for gold, the amount and quality of geological reserves of gold, the amount of investment to be made in geological prospecting, national exchange rate and key rate of the Bank of Russia. We substantiated the use of the linear three-factor model, which involves gold production volumes in Russia, demand for gold, national exchange rate and price for gold as regressors. According to our estimates, in the Russian Federation, gold production will have reached 370–380 tons by 2025. Conclusions. Based on the least square method, the structural forecast apparatus does not account for geological and geographic-economic distinctions of gold deposits due to their unique nature. Therefore, determining regressors for the model, we predominantly focuses on open access data.

Estimation of Mercury Losses and Gold Production by Artisanal and Small-Scale Gold Mining (ASGM)

Artisanal and small-scale gold mining (ASGM) utilizes mercury (Hg) for the extraction of gold (Au) and is responsible for the largest anthropogenic source of emissions and releases of Hg to the environment. Previous estimates of Hg use in ASGM have varied widely. In this effort, Hg losses in ASGM were derived from the difference between estimates of total Au production and the production reported by conventional gold mining. On the basis of this result, the average ratio of Hg lost to Au produced in ASGM was estimated to be 1.96 in Africa, 4.63 in Latin America, and 1.23 in Asia. The difference among regions can be attributed to the amalgamation procedure used by the miners, in which whole-ore amalgamation is predominant in Latin America and Asia. The obtained estimated ratio of Hglost:Auproduced suggested the possibility to detect either Au or Hg smuggling from one country to another. On the other hand, the importance of considering cyanidation in ASGM was also suggested. Graphical Abstract

A new kind of invisible gold in pyrite hosted in deformation-related dislocations

Mining of “invisible gold” associated with sulfides in gold ores represents a significant proportion of gold production worldwide. Gold hosted in sulfide minerals has been proposed to be structurally bound in the crystal lattice as a sulfide-gold alloy and/or to occur as discrete metallic nanoparticles. Using a combination of microstructural quantification and nanoscale geochemical analyses on a pyrite crystal from an orogenic gold deposit, we show that dislocations hosted in a deformation low-angle boundary can be enriched in Ni, Cu, As, Pb, Sb, Bi, and Au. The cumulative trace-element enrichment in the dislocations is 3.2 at% higher compared to the bulk crystal. We propose that trace elements were segregated during the migration of the dislocation following the dislocation-impurity pair model. The gold hosted in nanoscale dislocations represents a new style of invisible gold.

The native gold extracted in the Amur Region for 150 years

Data on gold production history and typomorphic features of native gold from the Amur province are provided. It is shown that about 1,116 t of primarily placer gold was extracted for 150 years, with primary gold accounting for 23,8 %. Placer gold sample distribution is unimodal with a maximum ranging within 850–925 ‰. Mercury prevails in microimpurities, its content in some clusters reaches the first percentage points. In terms of composition impurities, placer gold corresponds to gold from fields and occurences of gold-quartz and gold-sulfide-quartz formations. Low-fineness gold, (799–700 ‰) less common in placers, resulted from destruction of gold-silver unit sources while that of average fineness (800–900 ‰) was a result of the same process related to gold-polymetallic and gold-sulfide units. Gold-copper-molybdenum porphyry deposits do not form placers. The prospects of primary and placer gold production in the Amur region are defined.

Characterization of high-grade gold deposits of the northeast of Antioquia-Colombia

Mineralogical characterization is a fundamental stage when designing and implementing metallurgical extraction processes; in the case of gold mining, knowing the way the metal occurs and its mineralogical associations is a fundamental tool when minimizing losses or designing processes. The northeast of the department of Antioquia has distinguished itself as one of the main areas of Colombia in terms of gold production. In the present work, a characterization of different samples from this Colombian region was made using XRD, XRF, QUEMSCAN, SEM-EDX, fire assay, conventional cyanidation and froth flotation tests. The analyses performed classify these deposits as high grade, with values up to 81 g/t of gold. Quartz is the most common mineral followed by the presence of muscovite, pyrite and potassium feldspar. Regarding gold, it was found in the form of electrum associated with sulphide minerals, a conventional flotation process is proposed, with an average recovery of 90%.