BazTech - Yadda

1

Diagnostic gold deportment studies and leaching behaviour of small-scale gold mining tailings from eastern region, Ghana

Quaicoe Ishmael, Beyuo Martin, Quaicoe Solomon, Lasidzi Nikao A.

Journal of Sustainable Mining

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2023

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Vol. 22. iss. 2

81--88

EN

Artisanal and small-scale gold mining (ASGM) sector employs about 80% of the mining workforce but only contributes about 20-30% of Ghana's gold production. The low gold production is linked to low recoveries associated with the activities because of inadequate understanding of the chemical, mineralogical and metallurgical characteristics of the ores. This study examined the metallurgical characteristics of typical small-scale gold mining tailings to understand their grinding characteristics, gold deportment and cyanidation behaviour. The gold deportment results showed that 96.1% of the gold in the samples is free milling (can be leached directly with cyanide and recovered through carbon adsorption), whilst the remaining 3.9% of the gold in the samples is associated/locked up with other mineral phases (carbonates, sulphides, carbonaceous matter and quartz). The gold-by-size distribution also indicated that 73.1% of the gold is contained in coarser size fractions (+150 mm), 14.96% is from -150 mm to +75 mm size range, and 11.83% is contained in the finer size distribution (-75 mm). This suggests that incorporating a gravity recovery system during processing will be highly advantageous. The leaching kinetics results showed that gold recoveries achieved within 8, 16 and 24 h were 68, 73.8 and 76.4%, respectively. The corresponding total cyanide consumption rates after 8, 16 and 24 h of leaching were 550, 580 and 600 ppm, respectively. Generally, the gold recoveries and the cyanide consumption rates agree with industrial practices/results. Overall, the outcomes of the study support the view that some small-scale gold mining tailings are economically viable, and hence can be re-processed through efficient processes such as carbon-in-leach/carbon-in-pulp.

2

Interpretation of remote sensing and aeromagnetic data to depict the structural framework of the transitional zone between the Igarra Schist belt and Anambra Basin, Nigeria

Salawu Naheem Banji

Acta Geophysica

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2023

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Vol. 71, no. 1

227--246

EN

High-resolution aeromagnetic and Landsat-8 data were utilized for the structural investigation of the Igarra Schist Belt located where the Precambrian crystalline basement is unconformably overlain by the late-Cretaceous Anambra Basin fill. Analysis of the Landsat-8 data exhibits major lineaments that trend in E–W, ENE–WSW, NNW–SSE and N–S directions. Results from the analysis of total field anomaly data using total gradient amplitude and tilt angle of the horizontal gradient also show these same lineament trends. The superimposition of Landsat-8 and aeromagnetic data-derived lineaments resulted in the mapping of the regional lineaments, which provide clues to structurally controlled gold mineralization in the Igarra Schist Belt region. Details mapped from the remote sensing data show surface contacts that correspond to the boundary between the Igarra Schist Belt and Anambra Basin mapped from aeromagnetic data. The source parameter imaging of the aeromagnetic data provides depth estimates of the magnetic basement of the Igarra Schist Belt and Anambra Basin, which varies from 50 to above 650 m. The integration of the remote sensing and aeromagnetic lineaments with the 3-D Euler deconvolution results reveals that the locations of cluster solutions alignment with lineaments are target areas for gold mineralization, which is correlative to gold occurrences in the region.

3

Investments in gold or cryptocurrencies? Safe haven during the Covid-19 pandemic

Przyłuska-Schmitt Judyta, Jegorow Dorota, Bučková Jaroslava

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2022

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z. 158

489--500

EN

Purpose: The aim of the article is a comparative analysis of selected cryptocurrencies and gold in the context of the SARS-CoV-2 coronavirus pandemic. Design/methodology/approach: The study covered the stock exchange of Gold and the four largest cryptocurrencies in terms of market capitalization: Bitcoin, Ethereum, Binance Coin, and Cardano. The data for the analysis for the period 2020-2021 was taken from the internet platform www.coinmarketcap.com, where all cryptocurrencies are published in daily intervals, and from the Investing website www.investing.com for Gold. The analysis of data in the form of time series was carried out, based on the assumption that successive values in the data set represent successive measurements made at equal time intervals. Findings: Our findings prove that the studied cryptocurrencies proved to be resistant to economic fluctuations related to the pandemic crisis. Originality/value: We present original scientific research that provides useful information in a practical dimension for investors interested in the cryptocurrency market and safe assets, and anyone interested in the specificity of the problem at hand.

4

Prospects for thiourea as a leaching agent in Colombian gold small-scale mining: a comprehensive review

Borda Johana, Torres Robinson

Journal of Sustainable Mining

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2022

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Vol. 21, iss. 4

298--308

EN

Thiourea, as an alternative medium, is one of the most promising leaching agents for gold recovery by its commercial benefits and research challenges associated with performance and environmental impacts. This review article describes the operational conditions for the use of Thiourea vs cyanide, its chemistry, limitations, toxicity factors, environment, and recovery processes. Although thiourea gold extraction processes have not been applied on a large scale due to the instability of the reagent, its potential to overcome the limitations of cyanide is attractive to the process; with pH, potential, oxidant dosage, and temperature control, solubilized gold thiourea species are achieved. These can be recovered from the pregnant leach solution through methods such as activated carbon absorption and adsorption, polyurethane foams, ion exchange, and electrodeposition.

5

Cenne surowce z e-odpadów na wyciągnięcie ręki

Sikorski Wojciech

Energia i Recykling : gospodarka obiegu zamkniętego

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2022

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nr 4

PL

Obecnie, w dobie ciągłych braków towarów, galopującej inflacji i problemów na różnych szczeblach polityki międzynarodowej, każdy surowiec jest niezwykle cenny. Cóż zatem można powiedzieć o sytuacji, gdy wraz z niektórymi towarami, które straciły już swoją przydatność – najczęściej z uwagi na popsucie się – pozbywamy się pewnych ilości drogocennych substratów tworzących wspomniane dobra? Chodzi tu między innymi o miedź, srebro, złoto, platynę oraz pallad.

6

Assessment of gold with titanium alloy weldability in conditions of a dental technique laboratory

Jania G., Żmudzki J., Topolska S.

Archives of Materials Science and Engineering

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2022

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Vol. 118, nr 1

36--41

EN

Purpose: In dental practice, there is necessary to weld gold with titanium under the conditions of a dental technique laboratory, which is difficult. The aim was to assess the weldability of pure gold with the titanium alloy Ti6Al4V using a prosthetic laser welding machine. Design/methodology/approach: Gold wire in a diameter of 0.4 mm made with the use of a jewellery drawbar (GOLDPORT, Szczecin, Poland) was welded to a titanium alloy Ti6Al4V substrate of dental implant abutment screw (MegaGen). Dental laser welding parameters (Bego Laser Star T plus) were 230 V; 6.5 ms; 2.5 Hz; laser spot 0.3 mm, and argon blow. Samples were included in resin, ground (500-4000 SiC), polished (Al2O3 suspension) and etched (Kroll solution) per 20 s before observation under a light microscope. Findings: There were well-welded and poorly joined zones. The discontinuities and voids there were not visible or sparse next to the initial weld point. Dendritic structure at well-welded remelting zones and two-phase microstructure of titanium and Ti3Au phase were found. The heat-affected zone was about of 20 microns. Research limitations/implications: Light microscopy was used, and precise phase identification required further investigations. Weld strength assessment requires further micro-hardness and load-bearing ability tests. Weldability concerns the model system with pure gold. Practical implications: In the case of elements with dimensions below 0.4 mm, the use of a laser with a smaller spot should be considered for better control of the remelting zone and mechanical positioning of the elements in order to stabilize and avoid discontinuities and voids. Originality/value: Prosthetic laser welding with a laser spot about of 0.3 mm allows to obtain well-welded parts of 0.3 mm in diameter under stable stitching conditions and higher than 0.4 mm in dimensions.

7

Socio-ecological analysis of artisanal gold mining in West Africa: a case study of Ghana

Takyi Richard, Hassan Rasha, El Mahrad Badr, Adade Richard

Journal of Sustainable Mining

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2021

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Vol. 20, iss. 3

206--219

EN

The surge in artisanal gold mining (AGM) activities and the associated environmental impact in Ghana have elicited several stakeholders' attempts to curb the problem. However, due to little understanding of the underlying issues, these efforts have been ineffective. This study aims to use a socio-ecological framework to analyze drivers of AGM activities, the environmental pressures, the state change, their impact on human welfare, and the management response as measures (DAPSI(W)R(M)) to the problem. Evaluate AGM's impact on Ghana's ability to achieve the United Nations Sustainable Development Goals (SDGs). Data were collected from relevant literature on the subject and analyzed with the DAPSI(W) R(M) framework. Esteem needs, food, acceptance and friendship, and self-actualization are the main drivers of AGM activities leading to environmental pressures, including abrasion, extraction of living and non-living resources, the introduction of non-synthetic compounds, among others. State changes of the environment resulting from the pressures generated by human activities were changes in the land and forest cover (1.13%), topography (hills turned into flatland and undulating), and biota. Due to the state in the environment, water quality and availability, agriculture food production, fish yield, food safety, spiritual and cultural loss, death, injury, and health of gold miners and other stakeholders have been affected.

8

Environmental, health and safety intricacies of artisanal mining in the gold-rich landscapes of Karamoja, north-eastern Uganda

Serwajja Eria, Mukwaya Paul Isolo

Journal of Sustainable Mining

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2021

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Vol. 20, iss. 2

90--108

EN

Artisanal small-scale gold mining presents numerous opportunities for Uganda's rural poor. However, it also poses serious environmental, health and safety challenges. A suite of data collection methods including interviews, focus groups discussions, water and soils sampling were used to examine the perceptions of miners on the status, prevalence and extent of mercury use in artisanal gold mining, mercury transit routes and toxicity levels of soils and water in Karamoja sub-region. It also explores the health, safety and environmental implications of artisanal small-scale gold mining in the sub-region. The findings show that trade and access to mercury is widespread; although trade in, access to and its use is highly secretive. Traders access mercury through a number of ways including smuggling across the porous borderline and formal, but covert, importation. Miners then discreetly access it through undercover sales in jewellery shops and in affluent gated communities in Uganda's capital, Kampala. Soil and water samples showed mercury levels that exceeded the minimum acceptable limits of 0.03 mg/kg and 0.006 mg/l respectively. Further, artisanal small-scale gold mining is associated with massive land clearances and landscape deformations. It has invariably scarred the countryside with piles of waste and uncovered pits that are a source of accidents and ideal breeding grounds for vectors.

9

Evaluation of the extractive gold process: open-pit mining through exergy analysis

Velasquez Hector I., Orozco Loaiza Carlos Andres, Hasenstab Christian, Cano Natalia A.

Journal of Sustainable Mining

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2020

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Vol. 19, iss. 3

166--181

EN

The Colombian mining sector is characterized by the production of coal, nickel, emeralds, gold, and construction materials. It is considered by the National Development Plan of Colombia 2018-2022 as an economic agent that boosts development in the region and one that requires the strengthening of its policies and environmental liability. Therefore, this paper aims to show the importance of implementing methodologies based on the logic of nature (exergy) that objectively indicate the environmental impact of an extractive gold activity, such as open-pit gold mining. The extractive activity or process to be studied consists of the following stages: topsoil removal by using machinery and explosives to create craters and to access the mineral present in the subsoil; the physical transformation of the extracted material through crushing, grinding, gravimetric separation, flotation, leaching, adsorption, elution, and electrodeposition, along with smelting and casting to obtain gold and silver ingots. Thus, this paper analyzes the exergy performance of each unit process of the open-pit extractive process. The obtained results are used in a sensitivity analysis, which determines the system efficiency, by assuming the increase of gold in the extracted material in the exploitation stage, by using the same supplies and input of the current process. In other cases, the open-pit mining process is analyzed by changing its technologies in the mining process and assuming that this change reduces the inlet ore to 60%, by discarding 40% of material without gold and by reducing supply consumption by 25%. By improving the system efficiency, the exergy destroyed is reduced and the emissions to the environment diminish. Therefore, this method may be implemented as a basic guideline when it comes to decision-making processes in the planning of the extractive processes by integrating the environmental component with gold production.

10

Szkła złocone. Historia, technika, artyzm

Włodarczyk Adam

Szkło i Ceramika

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2019

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R. 70, nr 4

5--8

PL

Udany duet może być przepisem na ponadczasowy sukces, a niebanalne połączenia pomagają zapisać się na wieki w pamięci pokoleń. Obszar sztuki wydaje się być szczególnie podatny na doświadczenia z łączeniem materiałów i form, a odważne zestawienia nierzadko dają zaskakująco pozytywne rezultaty. Eksperyment łamiący obowiązujące zasady nie był cechą awangardy XX w., lecz przejawiał się w każdej epoce historycznej. Wariacją tego rodzaju można nazwać śmiałe, a nawet ekstrawaganckie połączenie szkła oraz złota. Kompilacja tak skrajnie odmiennych materiałów była synonimem luksusu nie tylko w baroku – epoce zbytku i nadmiaru. Techniki złocenia szkła mają bardzo długą tradycję. Wśród nich lepiej znanymi są „gorąca”1 fondi d’oro i „zimna”2 verre églomisé. Genezy tych technik można szukać przed wiekami, w epoce starożytnej. Niniejszy artykuł obejmuje swym tematem wyłącznie przegląd fizycznych procedur dekoracyjnych, zarówno „na gorąco” jak i „na zimno”. Autor pomija chemiczne procesy stosowane w produkcji szkła, jak wykorzystanie złota koloidalnego, proszków i związków złota wprowadzanych do masy szklanej, wychodząc z założenia, że temat ten zasługuje na osobne opracowanie.

EN

A successful duo can be a recipe for a timeless success. Original connections help to save in the memory of generations. The area of art seems to be particularly susceptible to experiments with combining materials and forms, and bold statements often yield surprisingly positive results. The experiment breaking the binding rules was not a feature of the 20th century avant-garde, but was manifested in every historical period. A variation of this kind can be called a bold or even extravagant combination of glass and gold. Compilation of such extremely different materials was, became a synonym of luxury not only in the Baroque – an era of excesses and excess. The glass gilding technique have a very long tradition. Among them better known are “hot” fondi d’oro and “cold” verre églomisé. The genesis of these techniques can be sought for centuries, in the ancient era. This article covers only the overview of physical decorative procedures, both cold and hot. The author overlooks the chemical processes used in the production of glass, such as the use of colloidal gold, powders and gold compounds introduced into the glass mass, assuming that the subject deserves a separate study.

11

Badania możliwości roztwarzania złomu elektronicznego

Piwowońska Justyna, Benke Grzegorz

Rudy i Metale Nieżelazne Recykling

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2019

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R. 64, nr 7

3--10

PL

Problem zagospodarowania zużytego sprzętu elektronicznego oraz jego skomplikowany recykling powoduje ciągłe poszukiwania nowych, innowacyjnych metod przerobu. W artykule przedstawiono wyniki badań dotyczące możliwości roztwarzania zużytego złomu elektronicznego przy użyciu kwaśnego roztworu potrawiennego, będącego mieszaniną chlorków miedzi i wolnego kwasu chlorowodorowego. Sprawdzono wpływ temperatury, sposobu utleniania oraz czas reakcji na wydajność roztwarzania. Opracowano wstępny schemat blokowy przerobu złomu elektronicznego.

EN

Management of waste electrical and electronic equipment as well as its complex recycling require searching for alternative processing methods. Results of the investigation on the possibility of digestion of used electronic scrap in acidic pickling solution, which is a combination of copper chlorides and free hydrochloric acid, was presented in this paper. The effect of temperature, oxidation, and reaction time on digestion performance was tested. A preliminary block diagram for electronic scrap processing has been developed.

12

Identyfikacja domieszek V, Co, Ni i Au w minerałach kruszcowych rud Fe-Ti-V (NE Polska) na podstawie analiz mikrosondą rentgenowską (EMPA)

Sadłowska Katarzyna, Mikulski Stanisław Z.

Przegląd Geologiczny

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2019

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Vol. 67, nr 3

192--195

EN

The main objective of this study was to quantitatively and qualitatively idenify trace metal admixtures in ore mineralsfrom Fe-Ti-V ore deposits within the Suwałki Anorthosite Massifin NE Poland. Chemical composition of ore minerals was determined using the CAMECA SX-100 electron microprobe and scanning electron microscope. The most abundant trace elements were Ti and Vhosted in oxides and Co, Ni, Cu, Zn contained in sulphides such aspentlandite, pyrrhotite, chalcopyrite, pyrite, siegenite, millerite. Scarce occurrences of native Bi, hessite and greenockite were identified. Samples, which were depleted in iron oxides were enriched in REE due to the presence of zircon, apatite and monazite.

13

Nanokompozytowe materiały węglowe z nanocząstkami złota : synteza, charakteryzacja, zastosowania

Rymarczyk Joanna, Czerwosz Elżbieta

Elektronika : konstrukcje, technologie, zastosowania

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2019

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Vol. 60, nr 12

14--18

PL

W artykule przedstawiono sposób syntezy nanokompozytu węglowego z nanocząstkami złota (warstw C-Au), charakteryzację oraz potencjalne możliwości aplikacyjne warstw w oparciu o ich właściwości fotoelektryczne i/lub fototermiczne. Omówione zostały wyniki badań topografii warstw otrzymane metodą skaningowej mikroskopii elektronowej, morfologii - metodą spektrometrii rentgenowskiej z dyspersją energii, budowy krystalicznej - metodą dyfrakcji promieniowania rentgenowskiego i struktury elektronowej - metodą spektroskopii w zakresie światła widzialnego oraz bliskiego ultrafioletu.

EN

In this article the method of synthesis of carbon nanocomposite materials with gold nanoparticles was presented. The characterization and potential application of this films based on their photoelectric and / or photothermal properties were shown. The results of topography studies obtained by scanning electron microscopy, morphology - X-ray spectrometry with energy dispersion, crystal structure - X-ray diffraction and electron structure - visible and near ultraviolet spectroscopy are discussed.

14

Silver and gold ions recovery from batch systems using Spirulina platensis biomass

Cepoi Liliana, Zinicovscaia Inga, Chiriac Tatiana, Rudi Liudmila, Yushin Nikita, Miscu Vera

Ecological Chemistry and Engineering. S

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2019

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Vol. 26, nr 2

229--240

EN

In order to assess ability of Spirulina platensis to recover silver and gold ions from the environment the bioaccumulation of silver and gold ions and their effect on growth, proteins and carbohydrates content of Spirulina platensis biomass was studied. Silver nitrate (AgNO3) in concentration range 0.01-1 mg/dm3 and tetrachloroaurate Na[AuCl4] in concentration range 18.5-370 mg/dm3 were added as component of the Spirulina platensis cultivation medium. In case of silver two cultivation media were studied: standard and Cl-free. The process of silver and gold uptake was traced using neutron activation analysis. Presence of silver ions in standard cultivation medium reduced biomass productivity by 66 %, while in Cl-free biomass productivity was reduced by 11.8 % only. The reduction of proteins content by 30 % in Cl-free medium and by 19 % in standard medium was also observed. The experiments showed that in case of gold ions loading, the biomass productivity and protein content were reduced only at high Na[AuCl4] concentration in the medium. The behaviour of carbohydrates content change was similar under silver and gold loadings: decrease at low metal concentration followed by increase at high metal concentrations. Scanning electron microscopy allowed observation of spherical metal nanoparticles, which were formed extracellularly during silver and gold bioaccumulation. Spirulina platensis can be used for recovery of precious metals as well as metal nanoparticles production.

15

Nauka o surowcach kołem zamachowym chińskiej gospodarki

Maksymowicz A.

Przegląd Geologiczny

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2018

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Vol. 66, nr 7

417--418

EN

The demandfor important raw materials for the Chinese economy achieved the scale about the half of the world's demand. Investment decisions taken in this matter enable a complete identification of mineral deposits, which is significant for both domestic and foreign investments. Geological studies and prospecting for useful ore mineral deposits have been conducted by special research institutions that prepare information about their reserves and output profitability. The University of Geological Studies in Beijing, with about 40,000 students, plays a key role in this activity. For example, a development of both reforms in extracting bituminous coal and gold deposits was discussed.

16

Valorisation of Mining Waste for Gold Recovery

Ubaldini S., Guglietta D., Ubaldini G., Michelis I. de

Inżynieria Mineralna

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2018

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R. 20, nr 2

281--288

EN

Purpose: the metals and industrial minerals contained in the tailings produced by mining and quarrying activities, are cause of environmental damage. The objective of this experimental work is the application of innovative technologies for the treatment and exploitation of mining tailings in Romania, in order to recover materials high grade raw to be placed on the market, reducing the volume of the wastes. Further objective, is to optimize some parameters relating to the dissolution of gold and the subsequent recovery from purified solutions, determining beforehand the technical feasibility of the scheme of process developed on a laboratory scale. Methods: the study is focused on hydrometallurgical process for the recovery of gold. The innovative treatment chosen is the thiosulphate process that, compared to conventional cyanide, has several advantages, first of all the most eco-friendly and non- toxic to humans. The conventional process shows operating limits in the case of auriferous minerals refractory materials, such as Romanian wastes object of the study. Another fundamental characteristic of the ammoniacal thiosulphate solutions, is the best selectivity towards gold, not attacking the majority of the gangue mineral constituents. Results: the dissolution rates of gold reached a final value of 70% Au – working at room temperature – with recoveries of the global process of about 65%, in line with the conventional process. Main conclusions: these results are very encouraging, considering that this is an innovative process, applied to a low content gold ore. The optimization of parameters and operating conditions, and the industrial treatment, continuous and scale greater would certainly permit to reach the best results in terms of process yields and energetic and reagents consumption.

PL

Cel: metale i minerały zawarte w odpadach powstających w wyniku działalności górniczej i wydobywczej są przyczyną szkód w środowisku. Celem prac eksperymentalnych jest zastosowanie innowacyjnych technologii do obróbki i eksploatacji odpadów wydobywczych w Rumunii, w celu odzyskania wysokiej jakości surowców, które zostaną wprowadzone do obrotu, zmniejszając ilość deponowanych odpadów. Dalszym celem jest optymalizacja niektórych parametrów związanych z rozpuszczaniem złota i późniejsze odzyskiwanie z oczyszczonych roztworów, z określeniem technicznej wykonalności schematu procesu opracowanego w skali laboratoryjnej. Metoda: badanie koncentruje się na procesie hydrometalurgicznym odzyskiwania złota. Innowacyjnym sposobem jest zastosowanie do ługowania tiosiarczanu, który w porównaniu z tradycyjnym cyjankiem ma wiele zalet, przede wszystkim jest bardziej przyjazny dla środowiska i nietoksyczny dla ludzi. Konwencjonalny proces daje ograniczone wyniki dla badanych odpadów złotonośnych. Podstawową zaletą amoniakalnych roztworów tiosiarczanu jest lepsza selektywność w stosunku do złota, a nie ługowanie wszystkich składników mineralnych skały płonnej. Wyniki: wskaźniki rozpuszczania złota osiągnęły wartość 70% Au - w temperaturze pokojowej - w porównaniu do odzysku z procesu konwencjonalnego około 65%. Główne wnioski: wyniki są bardzo zachęcające, proces jest innowacyjny, zastosowany do rudy o niskiej zawartości złota. Optymalizacja parametrów i warunków pracy oraz wdrożenie w skali przemysłowej pozwoli osiągnąć lepsze wyniki pod względem wydajności procesu oraz zużycia energii i odczynników.

17

O „krwawych” surowcach mineralnych i nie tylko

Kicki J.

Inżynieria Górnicza

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2018

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nr 4

24--27

PL

To miał być artykuł na koniec wakacji, ale może dobrze się stało, że napisałem wtedy nieco bardziej rozrywkowy tekst o podróżowaniu. Ten poniżej zmusza do chwili refleksji i wpisuje się w szeroko dyskutowany problem wzrostu zapotrzebowania i spadku wystarczalności surowców mineralnych, a także pogoni za nimi.

18

Zastosowanie analiz chemiczno-mineralogicznych złota okruchowego w prospekcji okruszcowania polimetalicznego

Kania M.

Górnictwo Odkrywkowe

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2018

|

R. 59, nr 3

115--122

PL

Przedstawiono wyniki analiz składu chemicznego złota okruchowego z potoku Jamna oraz obecnych w nim inkluzji kruszców. Rezultaty badań wykorzystano w identyfikacji obszarów alimentacyjnych miejscowych wystąpień rozsypiskowych. W aluwiach potoku Jamna ziarna złota jednofazowego z wrostkami galeny, arsenków i siarkoarsenków Co-Fe-Ni współwystępują z ziarnami złota dwufazowego, zawierającego fazy Hg-nośnego elektrum. Zróżnicowanie składu chemicznego ziaren świadczy o pochodzeniu złota z dwóch odmiennych genetycznie obszarów źródłowych: polimetalicznych żył hydrotermalnych oraz okruszcowanych skał osadowych permu.

EN

Results of the chemical composition of the gold grains from Jamna stream and occurring inclusions of ore minerals have been presented. Results have been used to identify the potential alimentary areas of the placer gold grains. Gold grains from the alluvial deposits of Jamna stream is represented by single-phase gold with inclusions of galena, Co-Fe-Ni arsenides, sulpho-arsenides and by biphasic gold, containing Hg-bearing electrum. Differentiation of the grain’s chemical composition is an evidence of the gold’s origin from two genetically distinct source areas: polymetallic hydrothermal veins and ore-bearing Permian sedimentary rocks.

19

Rola państwa w zagospodarowaniu niektórych surowców - wybrane przykłady

Solecki A.

Górnictwo Odkrywkowe

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2018

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R. 59, nr 3

10--14

PL

Przedstawiono historyczne przykłady rozwiązań organizacyjno-prawnych związanych z eksploatacją surowców mineralnych. Wybrane przykłady obejmują złoto, guano i bursztyn i ilustrują problemy prawno-społeczne związane zarówno z występowaniem surowców poza obszarem suwerenności danego państwa jak i problemy związane z trudną do udokumentowania zasobów formą występowania złóż. Opisane rozwiązania obejmują zarówno pełną liberalizację poszukiwań i wydobycia małych złóż okruchowych (złoto; Rosja, USA) jak i militarne i polityczne wsparcie państwa przy akwizycji obszarów perspektywicznych (guano; USA). Szczególną uwagę poświęcono bursztynowi dla którego zaproponowano rozważenie możliwości liberalizacji podobnej do stosowanej w przypadku małych złóż złota w Rosji, zarówno carskiej jak i posowieckiej.

EN

Historical examples of organizational and legal solutions related to the exploitation of mineral resources are presented. Selected examples include gold, guano and amber and illustrate legal and social problems related to both the occurrence of raw materials outside the sovereignty of a given country, as well as problems related to the difficulties in evaluation of resources. The solutions described include both full liberalization of exploration and exploitation of small placer deposits (gold, Russia, USA) as well as military and political support of the state in the acquisition of prospective areas (guano, USA). Particular attention was paid to amber, for which it was proposed to consider the possibility of liberalization similar to that used for small gold deposits both in Tsarist and post-Soviet Russia.

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Mineralogical and morphological studies of gold-bearing arsenopyrite and pyrite minerals of Bakyrchik and Bolshevik gold black shale deposits (Eastern Kazakhstan)

Junussov M., Umarbekova Z.

Contemporary Trends in Geoscience

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2018

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Vol. 7, iss. 2

153--165

EN

Bakyrchik and Bolshevik both are sediment-hosted disseminated gold deposits. They are located in Eastern Kazakhstan (4 km in distance between deposits) and include in the Western Qalba metallogenic zone. They originated in late Paleozoic age along structured line between palaeocontinents of Kazakhstan and Altai-Mongol. The purpose of this paper is designation of typomorphic features of gold-bearing arsenopyrite and pyrite minerals, determination of chemical composition of these two sulfides minerals. The arsenopyrite and pyrite are the main objects for analytical study of gold-bearing sulfide minerals, their different textures, morphology of the crystals and aggregates. The studies of ore samples and minerals were carried out by methods of optical microscope, X-ray diffraction, X-ray fluorescence and electron microprobe analyses. The analytical study of sulphide minerals has shown that the arsenopyrite is acicular and tabular, pyrite has three varieties - globular, hexahedral and pentahedral forms in three rock samples of the carbonaceous-terrigenous formation in the deposits.