Search Documents

By M. Le Roux, Q. P. Campbell, N. Hughes

Water plays a significant role in minerals processing; this is especially true in coal preparation where water-based beneficiation is widely accepted and consistently delivering sharp separation efficiencies and high product yields. Although wet processing is favoured, the substantial process water requirement may prove this impractical and unsustainable in some parts of the world. Many coal-rich regions (including South Africa) have experienced severe water shortages. Coupled with the effects of drought, some countries experience freezing winters from which problems related to frozen process water and machinery may arise. Hence coal preparation practices will soon have to adapt, irrespective of the technical and economic feasibility offered by the currently employed water-based methods. As a result, extensive research into the development of dry methods for effectively beneficiating coal has progressed. This review paper intends to provide a collection of the relevant information pertaining to dry coal processing globally, and aid in understanding the applicability, performance, success or failure thereof. The methods available for dry materials preparation, with special regard to those applicable for coal beneficiation, are detailed in terms of principle, applicability, limitations and performance. Dry coal beneficiation has potential to aid the current wet-based methods with some considerations to possible limitations set forth by coal geology, application, product specification, particle size distribution, moisture, efficiency, capacity and cost. These methods may be established in future, especially in the arctic, arid and under-developed regions through new plant installations, expansions and small mines processing. Keywords: Dry coal processing, preparation, cleaning, beneficiation

Jan 1, 2020

By V. Maseko, C. Musingwini

"When considered collectively, Mineral Resources and Mineral Reserves are arguably a key asset for any mining company. Mineral Reserves are the economically mineable portions of Mineral Resources. They therefore provide a good indication of the economic prospects in the short to medium term and associated non-financial impairments for mining companies, hence a focus on Mineral Reserves. An assessment of modifying factors for converting Mineral Resources to Mineral Reserves revealed that Mineral Reserves were most sensitive to long-term commodity prices, hence the focus on long-term commodity prices. The justification for selecting gold and platinum mines is that they collectively make a significant contribution to South Africa’s earnings from mining.The introduction of the South African Code for the Reporting of Exploration Results, Mineral Resources and Mineral Reserves (SAMREC Code) in 2000 informed the basis for analysing long-term commodity price assumptions for major South African gold and platinum mining companies between 2000 and 2016. The analysis revealed that the least number of non-financial impairments occurred when long-term commodity prices were within ±5% of spot prices. This finding suggests that this range is the ideal range for long-term commodity price assumptions to improve confidence in Mineral Reserve declarations and minimize impairments. Introduction The South African Code for the Reporting of Exploration Results, Mineral Resources and Mineral Reserves (SAMREC Code) defines a Mineral Resource as ‘a concentration or occurrence of solid material of economic interest in or on the Earth’s crust in such form, grade or quality and quantity that there are reasonable prospects for eventual economic extraction’ (SAMREC, 2016, p. 18). Mineral Resources are categorized according to increasing levels of geoscientific confidence or knowledge, from Inferred to Indicated and lastly, Measured categories. The SAMREC Code defines a Mineral Reserve as ‘the economically mineable part of a Measured and/or Indicated Mineral Resource’ (SAMREC, 2016, p. 25). In some of the other reporting codes such as the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC Code), a Mineral Reserve is synonymous with an Ore Reserve. The conversion of Mineral Resources to Mineral Reserves involves applying modifying factors, which are non-resource considerations. The modifying factors used in the Mineral Reserve estimation process include mining, metallurgical, processing, infrastructure, economic, marketing, legal, environmental, social, and governmental factors. Each of these modifying factors consists of several components which require due consideration in the estimation of Mineral Reserves. Table I shows some of the components typically considered for each of the modifying factors."

Mar 1, 2019

By M. A. Mahboob, T. Celik, B. Genc

Mineral Resources estimation plays a crucial role in the profitability of the future of mining operations. The conventional geostatistical methods used for grade estimation require expertise, understanding and knowledge of the spatial statistics, resource modelling, geology, mining engineering as well as clean validated data to build accurate block models. However, the geostatistical models are sensitive to changes in data and would have to be rebuilt on newly acquired data with different characteristics, which has proved to be a time-consuming process. Machine learning methods have in recent years been proposed as an alternative to the geostatistical methods to alleviate the problems these might suffer from in Mineral Resource estimation. In this paper, a systematic literature review of machine learning methods used in Mineral Resource estimation is presented. This has been conducted on such studies published during the period 1990 to 2019. The types, performances, and capabilities, of several machine learning methods have been evaluated and compared against each other, and against the conventional geostatistical methods. The results, based on 31 research studies, show that the machine learningbased methods have outperformed the conventional grade estimation modelling methods. The review also shows there is active research on applying machine learning to grade estimation from exploration through to exploitation. Further improvements can be expected if advanced machine learning techniques are to be used.

Nov 30, 2022

By R. Nyirenda, B. Besa, N. Dzimunya

The accurate estimation of peak particle velocity (PPV) is crucial during the design of bench blasting operations in open pit mines, since the vibrations caused by blasting can significantly affect the integrity of nearby buildings and other structures. Conventional models used to predict blast-induced vibrations are not capable of capturing nonlinear relationships between the different blasting-related parameters. Soft computing techniques, i.e., techniques that are founded on the principles of artificial intelligence, effectively model these complexities. In this paper, we use the random forest (RF) algorithm to develop a model to predict blast-induced ground vibrations from bench blasting using 48 data records. The model was trained and tested using WEKA datamining software. To build this model, a feature selection process using several combinations of Attribute Evaluators and Search Methods under the WEKA Select Attributes tab was performed. The correlation coefficient of the actual data and RF model-predicted data was 0.95, and the weighted average of the relative absolute error (RAE) was 10.9%. The RF model performance was also compared to the equivalent-path-based (EPB) equation on the testing data-set, and it was seen that the RF model can effectively be used to predict PPV. The study also demonstrates that the EPB equation is a suitable empirical method for predicting PPV.

Mar 30, 2023

By Q. Zhang, X. C. Wang, X. Q. Ao

The flotation separation of apatite and calcium-bearing gangue minerals (dolomite and calcite) has always been a problem in phosphate ore mineral processing research. The crystal structure and surface properties of minerals have an important influence on their floatability. In this paper, the theoretical and comparative analysis of the crystal structure and surface electronic properties of apatite, dolomite and calcite were carried out using the first principle calculation based on density functional theory. As a supplement and validation, the surface wettability of three minerals under different flotation conditions were compared and analysed by contact angle test. The results theoretically revealed that the three calcium-bearing mineral surfaces have similar surface electronic properties and thus exhibit similar floatability. In the flotation process, the anion difference between apatite and carbonate gangue should be fully utilised, and the minerals can be separated only after surface modification by flotation reagent. The contact angle test shows that phosphate and carbonate can be separated by using anion flotation collector after surface modification with acid. It is expected that this research is of interest for understanding the surface structure and electronic properties of apatite and carbonate gangue minerals and providing the theoretical basis for surface interaction. Keywords: Apatite, dolomite, calcite, surface structure, electronic property, density functional theory

Jan 1, 2020

By E. P. Preis, R. C. W. Webber-Youngman

The real cost of any mining incident has, empirically, proven to be estimation-driven, rather than factdriven. One of the main reasons for this lies with the complexity of the cost composition of any given mining incident. Incident costs comprise both direct and indirect cost factors, and in many cases the costs associated with these factors are incurred during different time periods following the incident. In this paper we aim to identify the various cost factors arising from mining incidents, provide a thorough understanding of all the potential cost factors identified, and draw general conclusions on the knowledge obtained. Furthermore, recommendations are made on how mining companies could use the results, in order to assist them in calculating the costs of mining incidents. The paper also provides suggestions for further research, with the emphasis on the most significant immeasurable cost factors, namely the costs of implementing job accommodations following an incident, the harm to company reputation, and the decreased productivity due to low worker morale/psychological factors following an incident. If mining companies are aware of and understand which factors could contribute to the cost of any given incident, future planning and incident cost estimations could be easier. It should, however, be noted that although this study provides a comprehensive list of cost factors (and detailed explanations), other unknown cost factors relating to mine incidents could prevail in extreme cases.

Jan 1, 2021

By B. McFadzean, M. Tadie, T. Dzingai, M. Becker

Ores from a single deposit may exhibit extensive variability in their mineralogy and texture. The ability to quantify this variability and link it to mineral processing performance is one of the primary goals of process mineralogy. This study focuses on the effect of alteration in three platinum group element ore samples from the Great Dyke in Zimbabwe – two of which were more pristine compared to the third, which was locally classified as ‘oxidized’ ore. These ores are known to be characterized by varying degrees of alteration, resulting in numerous challenges in flotation and affecting both grade and recovery. Alteration, by near-surface oxidation, of the valuable base metal sulphides and platinum group minerals resulted in lower flotation recoveries of Cu, Ni, Pt, and Pd. Evidence of incipient oxidation was more readily observed in the base metal sulphide assemblage than the platinum group mineral assemblage, even though the loss in recovery (because of oxidation) was most significant for Pd. Alteration through hydration resulted in a significant increase in mass pull and dilution of concentrate grade through the inadvertent recovery of naturally floating gangue comprising composite orthopyroxene and talc particles. In this study, the amount of naturally floating gangue was more strongly correlated with the talc grain size distribution than the grade of talc in the flotation feed. The oxidation and hydration alteration reactions are not necessarily mutually exclusive, although one may be more dominant than the other, giving rise to ore variability.

Sep 1, 2021

By C. H. Wyndham, N. B. Strydom

INTRODUCTION Acclimatization of the labour force to heat is an integral aspect of gold mining in South Africa. A recent survey revealed that about 250,000 Bantu mine workers require to be acclimatized to heat each year. Until 1965 men were acclimatized by means of one of the Chamber of Mines methods (introduced by the Human Sciences Laboratory in 1953). This type of acclimatization was carried out underground where men shovelled rock in hot stopes under careful supervision. However, it has become increasingly difficult in the last few years for mines to provide underground the conditions of work and environmental heat required for adequate acclimatization to heat. In examining an alternative to acclimatization in underground hot stopes, the Human Sciences Laboratory carried out a trial in 1965 of acclimatization in an air-conditioned climatic room on the surface of a mine. The new procedures developed from this trial have been so successful that there are today 26 climatic rooms on different mines. These rooms have been built following a design proposed by Mr Hodgson of the National Mechanical Engineering Research Institute1. Approximately 85 per cent of the total number of men being acclimatized each year are put through the new procedures in these climatic rooms. This paper gives an account of the problems which arose and how they were solved, the inter-relationship between physical conditioning and climatic room acclimatization, the prodecures developed for elimination of labourers with low maximum oxygen intakes, and the advantages of climatic room acclimatization. CLIMATIC ROOMS The majority of the climatic rooms (twenty) have been built on the surface, but a number (six) of mines preferred to establish their acclimatization centres underground in order to decrease the initial costs involved in the construction of such facilities. These underground climatic rooms are usually located near shaft stations in redundant haulages and they can accommodate from 200 to 400 labourers, thus eliminating the need for multiple acclimatization shifts. Figs. 1-4 illustrate various aspects of a surface climatic room. PROBLEMS WHICH AROSE IN INTRODUCING CLIMATIC ROOM ACCLIMATISATION There were four main problems which arose in connection with the introduction of the new method. These were: (i) The type and rate of work to be used. (ii) The air conditions required to obtain optimum acclimatization. (iii) The duration of exposure to heat each day and the total number of days of acclimatization. (iv) The methods of cooling labourers with high body temperatures. Shovelling rock would have been the desirable type of physical work to employ, but the air-conditioned space required to accommodate large numbers of men and the difficulty in standardizing the work rate in shovelling led to the decision to employ instead the work procedure used by the Human Sciences Laboratory in acclimatizing men in the Laboratory. This is the lifting of the body weight against gravity when men step on and off a bench. It has the advantage that large numbers of men can work physically at the required rate in a relatively small space (120 men can be accommodated in an area of 70 ft by 21 ft) and the cost of construction and ventilation of the climatic rooms is thereby reduced. Also the work rate can be standardized by varying the height of the stepping benches in relation to the individuals' body weights. The next problem was the air condition to be used in the climatic rooms. The Laboratory's research experience in acclimatization led it to choose an air temperature of 89°F (with the air almost saturated with water vapour) and an average velocity of air movement of 100 fpm. This air condition was combined with a work rate of 1,560 ft lb/min (oxygen consumption 1.0 litre/min) on day 1, and the work rate was increased gradually over the period of acclimatization to reach a work rate of 3,120 ft lb/min (oxygen consumption 1.6 litres/min) on day 9.

This International Mine-Surveying Conference will take place in Budapest (Hungary) from 5 to 14 June, 1972. Detailed information can be obtained from the Mine-Surveying Working Committee of the Hungarian Mining and Metallurgical Society. Write: OMBKE Bányaméröi Munkabizottsag Budapest, V., Szabadsag ter 17, Hungary. SYMPOSIUM ON NICKEL The 'Gesellschaft Deutscher Metallhiitten-und Berglaute' is holding a Symposium on nickel on 24-25 September, 1970 at Wiesbaden, on the occasion of the G.D.M.B. Annual Meeting. Some 24 papers will be presented by metallurgists from many important companies around the world. Information may be obtained from The Secretary, G.D.M.B., Postfach 210, 03392 Clausthal-Zellerfeld, German Federal Republic. VISIT TO THE COUNCIL FOR SCIENTIFIC AND INDUSTRIAL RESEARCH On 23rd June, 1970, members of the Institute visited the C.S.I.R. in Pretoria. More members had booked for this tour but the current flu epidemic caused cancellations which was unfortunate. The visit was organised with military precision, which prevented detailed discussion of any particular subject, but provided a bird's eye view of a large number of interesting projects. The visit was packed with interest for all and those requiring further information were invited to contact the relevant divisions afterwards. Or Denkhaus welcomed the delegates and stressed the importance of integrating research efforts with industry's requirements. An excellent colour and sound film was shown which depicted the work of the Rock Mechanics division. This showed very clearly methods used for preparing rock samples and demonstrated the machines and instruments for the various tests. It made one realise the extent to which this research has been integrated with the actual mining situation. The fullscale experiments underground showed the failure of pillars under applied loads and were very interesting. This is undoubtedly a film which all mining people should see. After the film the rock mechanics laboratories were visited where the actual machines were seen and described. We then visited the metal and strength mechanics sections where the metallurgists were able to see some interesting experiments and tests. We also visited the Aeronautics Research group where a large 1 000 hp wind tunnel was inspected. We were told enough about this to realise something of the complexities involved in the design and operation of a closed circuit tunnel of this type. The tunnel is used for tests on models which are necessary for the design and modification of aircraft. After a very excellent lunch at the C.S.I.R. recreation centre, the delegates attended two lectures-one by Mr. Mandersloot of the Chemical Engineering group, who outlined the varied functions of this group and told us something of their work. Of particular interest was the research into the suitability of various South African manganese ores for dry cell batteries. Work on the thickener settlement studies interested the metallurgists. The second lecture was given by Mr Donaldson of the National Building Research Institute. This Institute has about ten divisions each of which covers a particular aspect of building research. The work of the soil mechanics division was described in detail and illustrated by coloured slides. This was particularly interesting and demonstrated clearly how building failures result from lack of attention to detail of construction where unstable soil conditions exist. Cracks in walls of compound blocks brought the subject home forcibly to the mining delegates. This division has also caried out important work on sinkholes and sUmes dams and produced some positive results. Altogether the visit was most interesting and enjoyable. It was made more worthwhile because the emphasis was on the work being carried out and not on just seeing the laboratories. The Institute is greatly indebted to the C.S.I.R. and its staff for the very excellent arrangements made.

By A. R. Miller

A fuel cell locomotive incorporates the advantages of its competitors, namely catenary-electric and diesel-electric units, while avoiding their disadvantages. It possesses the environmental benefits, at the vehicle, of an electric locomotive but the higher overall energy efficiency and lower infrastructure costs of a diesel locomotive. The natural fuel for a fuel cell is hydrogen, which can be produced from many renewable sources or via nuclear energy, and thus a hydrogen-fuel cell locomotive will not depend on imported oil. Hydrogen produced from renewable primary energies or nuclear energy would provide a totally zero-emissions vehicle, that is, with zero carbon in the energy cycle. A project partnership among Vehicle Projects Inc of the USA, and South African partners Anglo American Platinum, Ltd, Trident South Africa, and Battery Electric, has designed and is launching a series of five prototype fuel cell-powered mine locomotives.

Jan 1, 2012

By D. Stone, M. Le Roux, Q. P. Campbell, M. Fofana

Float-and-sink analysis is widely used in the coal industry to obtain washability data, yielding important information about beneficiation potential and performance. This method is associated with health and environmental problems, and research into alternative densimetric methods is important. The RhoVol is a new technology developed by De Beers Group Technology South Africa (DebTech) for the image-based generation of densimetric data from ores. The analysis is done on a per-particle basis, within a size range of +3 mm –8 mm. In this paper we compare the established methods used for the float-and-sink analysis of coal with a new method using RhoVol. The aim of the study was to determine the validity of the information obtained from the RhoVol analyser by performing comparative densimetric analysis on three different coal samples. The results showed that the RhoVol method was more rapid, safe, and precise, but tended to consistently underestimate the density of the coal sample, probably due to varying coal porosity.

Oct 3, 2023

By J. H. French, O. E. Lissner

S. J. Venning (Member): The authors should be congratulated on producing such concise data from the plethora of experimental report results. Their observations on the cost of liners calls for some comment however, as the really unique feature about liners in South Africa is that they can be obtained so cheaply. Attention has been focussed on the 1961 cost of white iron at R50 per ton for chill cast block liners while manganese steel liners are reported as costing as much as R250 per ton. The former are however, a relatively heavy, simple casting with a low labour content and reasonably high percentage productivity, made from metal melted in a cupola. The capital investment to produce this type of casting is low compared with that required to produce manganese or other alloy steels. The chill cast liner block is always a production item and is cast in a permanent mould. Almost all manganese mill liners, except perhaps small aperture screens, are sold for considerably less than the R250 per ton quoted by the authors. Where a price of this nature is asked it would be because the design of the casting demanded is complicated or leaves little metal to carry the labour and other costs of production. As reference has also been made in the paper to liner costs in America, prices for similar types of liners obtained during a visit to Canada and the U.S.A. in 1961, could be of interest: Material Price per Location short ton Ni-hard R250 Elliot Lake Body liners block type Ni-Hard R300-310 FAS New York Mn Steel R280-290 FAS New York Screens (grids) slotted Cr.Mo. Steel R600 FAS New York hole Ni-Hard R320 Elliot Lake At this time the price of comparable manganese steel block type liners on the Witwatersrand was between R145/R155 per short ton. White iron in Canada was then quoted at about R150 per ton, but as Ni-Hard gave a life of at least two to twoand-a-half times that of white iron, it was a much more attractive proposition particularly when relining and down time costs were taken into consideration. There is little doubt that most foundries would welcome clear and complete specifications of the customers requirements and systematic checks to ensure that these specifications are being met. B.S.S. or other accepted standards should form the basis of these, and periodic inspections should be undertaken to ensure that only those foundries capable of complying should be included as suppliers. The authors have referred to new designs, but can the industry really call the grid and plate new when the patents were taken out during the second world war and the sawtooth block has been used for at least 35 years. Unfortunately, far too little thought and consideration are normally given to the ultimate mill liner design while the mills themselves are on the drawing boards. The position and size of the door opening, which is the key to the ultimate shell liner configuration, the drilling of the

Jan 9, 1968

By X. Gumede

Mud houses are common structures in most South African rural homes closer to the mining operations. Fulltime dwellers in these properties are often the elderly. The mine codes of practice and the South African legislative instruments attempt to define the damage criteria to limit the effect of the blast-induced noise and ground vibrations to different structures. All these assessment criteria are based on the peak particle velocity and noise generated during blasting. The South African safe limit criterion that was adopted was initially derived from the international standards, which were then used as a local guideline. This paper evaluates the currently adopted safe limit criteria used in South Africa for a mud house, currently rated at 6 mm per second and 120 decibels to134 decibels, for blast-induced seismicity and noise, respectively. Further, a study was performed on a residential house near a coal mine (5.26 km) based in Mpumalanga following numerous complaints by the owner, launched at the mine and to the Department of Minerals and Petroleum Resources. The aim of the study was to measure the magnitude of blast-induced triggers experienced at the aggrieved homestead and to establish if there is a likelihood that an irritation or damage may be caused by these triggers. The seismometer was installed at about 2 m from the mudhouse, from 1 July 2022 to 31 of July 2022. Five blast-induced triggers were recorded during the period showing an average of 0.09 mm/s and 121 decibels for blast-induced seismicity and noise, respectively. The results obtained indicated a maximum seismicity of 0.15 mm/s. This seismicity was below the perceptible vibrations obtained from daily home activities such as walking, jumping, and door slamming, which produce 0.8 mm/s, 7.1 mm/s, and 12.7 mm/s, respectively. Seismicity was therefore not likely to have caused any annoyance and or damage. For noise, the results indicated a maximum of 123 decibels and an average of 121 decibels from five events recorded. A literature review suggests that slight damage may occur when airblast frequencies match the natural frequencies of structures at 120 decibels. Based on these results, it can be concluded, therefore, that the noise, rather than seismicity, is more likely to be the cause of damage to the structure assessed. For improvement, a new approach is proposed based on relating the safe limits to the structural and human response.

Dec 15, 2025

By P. W. J. Delport, E. Du Toit

Investing in a mining venture can be risky and stakeholders need transparent, unbiased reports to understand the Mineral Resources and Mineral Reserves a mining company holds. Readability and textual choice can be used consciously to manipulate perceptions, or it can be done unconsciously. This exploratory study investigates the readability and textual choice of supplementary Mineral Resources and Mineral Reserves Reports of companies listed on the Johannesburg Stock Exchange. The results indicate that narrative manipulation occurs in these reports through word choices that make the reports difficult to read, as well as specific narrative selections. This reduces the informational value of the reports. The results of the study will be useful to various stakeholders, such as mining company management, investors, investment specialists, financial analysts, and even employees and the general community, who all use these reports to make important decisions. It is also useful for the preparers of the Mineral Resources and Mineral Reserves Reports, Competent Persons, and other technical specialists to be aware of readability and that certain textual choices can affect the interpretation of these reports. It is recommended that bodies such as the JSE and the SAMREC and SAMVAL Code committees consider adding a plain language requirement to regulations, guidelines, and codes to ensure transparent, unbiased, and objective reports.

Mar 1, 2021

By M. Bueno, T. Chavez Matus, M. S. Powell, S. Michaux, S. Luukkanen

Comminution tests are an essential element in the design of ore beneficiation plants. Many methods have been developed to assess the breakage characteristics of rocks to generate parameters for modelling. However, most of the existing methods are laborious, expensive and require large samples. Consequently, test work has been traditionally conducted with a few representative reference samples. On the other hand, geometallurgical modelling programs require an extensive amount of test work to allow understanding the variability of ore properties within the deposit and establish spatial geometallurgical domains that show the differential responses to mineral processing. Therefore, comminution tests for geometallurgy need to be more efficient in terms of time, cost and sample size. This paper introduces a new testing device (Geopyörä) which is capable of measuring forces and energy applied to rock particles during the breakage process. The new testing method uses smaller samples and can be up to 50 times faster than other commonly used tests in the industry. This paper presents the concept prototype and the preliminary test work results, which have been benchmarked against some of the industry standard tests, such as the JK Drop Weight Test (JKDWT), the SMC Test® and the Bond ball mill test. Keywords: Geometallurgy, comminution, ore breakage characterization, variability.

Jan 1, 2020

By L. W. Palmer

Compositing or regularization of drillhole data is common practice in mineral resource estimation and is deemed a necessary step in producing unbiased estimates of mineral resources and reserves. Commonly, data are collected over irregular distances due to the varying relative thicknesses of lithologies drilled or sampling/assaying strategies. This necessitates data transformation to regular lengths of equal size to ensure that all data have the same sample support. However, there have been few detailed publications on the effect of this process on the composited data that are subsequently taken forward for the estimation process. In this paper, three currently available compositing methods are reviewed and the effects of inappropriate compositing methodologies presented. It is shown through a case study that compositing samples to different lengths leads to changes in the average and variance of the grades in the drillcores in the dataset, which will impact the final estimated value. These differences are exacerbated by breaks or gaps in data where, for a variety of reasons, there has been no data collection or data have been lost. The importance of appropriately treating blank and zero data is also presented. Globally, these differences might be minimal, but locally may be substantial, affecting the efficiency of the estimation and subsequent use of the results in, for example, mine planning and reconciliation. Further detailed investigation of compositing practices is required if the full implications of compositing are to be understood and any induced bias effectively defined.

Jul 10, 2024

By N. V. Moraka

In dealing with transformational aspects, the South African Constitution aspires for a balance between attempts to broadly represent the country’s demographics in the way in which organizations are structured and the need to maintain the necessary skills to ensure continual retention of skills for optimum and efficient organizational performance. Through the Mining Charter, government aimed to redress gender and racial imbalances in the mining industry as part of transforming the demographic representation of mining companies to include black people, women, and people living with disabilities in all job levels up to top management. While the Constitution calls for an appropriate balance between demographic representation and competency, this aspiration for mining poses challenges for companies due to the proficient and competent skills needed in this industry. To this end, the South African mining industry has been subjected to substantial criticism from government regarding the slow progress of transformation. The mining industry justifies its slow pace of transformation by pointing at inconsistent, varying legislation and definitions governing transformation, limited skills available from historically disadvantaged groups, and cautioning not to compromise the sustainability of mining companies by marginalizing white males and white youth with the objective of addressing racial imbalances. This lack of understanding between industry and the government has led to considerable confusion regarding the accountability of stakeholders in transforming the industry. This article presents the perspectives of ten mining executives on transformation in the South African mining industry. The theoretical description of transformation, as well as other mining stakeholders’ interpretations of transformation. is presented. Qualitative data from interviews with mining executives demonstrates their understanding of transformation through rich descriptions, interpretations, and implications in their contexts. The findings demonstrate that transformation in the mining industry is not simply about race and gender, but about cultural change, a change in mind-sets, embracing diversity, equalizing rights and opportunities, and attaining social justice. Moreover, transformation is clearly a gradual process. The article concludes with a recommendation for the definition of transformation to be corroborated with the views of mining executives and that of the Constitution of South Africa. This will create an overarching, simplified definition of transformation that can be accepted and interpreted by all stakeholders.

Jan 1, 2016

By E. Chisakulo, M. W. Songolo, E. K. Chanda

Zambia’s mining industry has undergone various phases of mineral royalty changes since privatisation. Unlike many analyses that relied on subjective probability, this study employs the cut-off grade and mineral royalty model relationship to investigate how changes in mineral royalties impacted the net present value and cut-off grades of Zambian copper mines between 2008 and 2022. The results showed that net present value decreased by 10.39%, 6.13%, 9.69%, and 6.13% for Barrick Lumwana, Kansanshi, Nkana–Mopani Copper Mines, and Mufulira–Mopani Copper Mines, respectively, while First Quantum Minerals Trident’s net present value increased by 3.40%. Reductions in NPV correspond to higher government revenue, whereas the increase for FQM Trident reduced government revenue. For cut-off grades, returns increased by 0.42%, 1.20%, and 0.42% for Barrick Lumwana, First Quantum Minerals’ Trident, and Kansanshi, respectively, showing how portions of the Zambian copper orebodies accrued to investors, with a corresponding reduction in government revenue. Conversely, reductions of 0.24% and 0.38% for Nkana–Mopani Copper Mines and Mufulira–Mopani Copper Mines indicate that a share of the ore reserves accrued to the government, reducing investor returns. These findings demonstrate that mineral royalty adjustments redistribute economic value between investors and the government, affecting both profit margins and operational decisions. Despite these distributional effects, all projects remained economically viable. The findings underscore the need for an optimal mineral royalty framework that equitably balances the economic value of mineral resources between investors and the state

Jan 30, 2026

By G. E. Rencken, J. H. Potgieter, A. Narain, J. Smith

To conserve fresh water resources and comply with environmental regulations, DRDGOLD, a South African gold producer re-treating surface tailings, has transitioned to a fully closed water circulation system. Consequently, the accumulation of contaminants, as well as addition of reagents, has led to changes in water composition that have compromised leach performance and overall gold recovery. A two-sample t-test confirmed a significant difference in gold recoveries between the use of Rand Water, which was used as a benchmark, and untreated process water. Atomic absorption analysis of ERGO’s process water, confirmed the presence of iron, nickel, zinc, and manganese. A study of the effect of the identified contaminants on gold recovery showed that iron, nickel, and zinc have the largest negative effect on gold recovery, with iron and nickel being more detrimental than zinc. Sulphates were shown to have a possible passivation effect, which also influenced gold recoveries, although to a lesser extent than the heavy metals. Calcium, when present in excess, had a positive influence on gold recovery indicating the possible formation of a calcium aurocyanide complex. Lime softening successfully reduced the heavy metal and sulphate concentrations, and the gold recoveries obtained with the treated process water were similar to those as achieved with Rand Water.

Jul 1, 2021

By C. Bester, G. M. Rohde

A major challenge in the mining sector is the responsible management and efficient storage of mine residue. Over recent years numerous tailings dams have experienced unintended spills and failures, with severe consequences for the mining industry, the environment, local communities, and the regional economy. The fourth industrial revolution (4IR) is impacting society due to increased interconnectivity, processing speed, and automated technologies. This paper explores whether 4IR technologies have the potential to mitigate risks associated with tailings dams. Experts in the field of tailings dam operational management were surveyed to determine their view on the risks associated with tailings dams and the potential of 4IR technologies to mitigate these risks. The survey found that a majority of experts believe that certain 4IR technologies have the potential to reduce the risks associated with tailings dam failures.

May 27, 2025