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By N. K. Dumakor-Dupey, G. B. Sakyi-Addo, K. J. Bansah

"Artisanal and small-scale mining (ASM) occurs in many countries around the world, and provides a source of livelihood to many impoverished local people in areas where it occurs. This paper reports the role of female participants and reasons why they engage in ASM. Field visits were made to 12 ASM sites located in the Tarkwa Mining District of Ghana to conduct interviews with male diggers and female participants. It was observed that over 100 women between the ages of 18 and 50 participate in ASM for survival. They engage in ASM largely because they have no alternative employable skills and income sources. These female participants depend on ASM to sustain the lives of their dependents. INTRODUCTION Artisanal and small-scale mining (ASM) conventionally involves use of rudimentary tools (such as picks, shovels, chisels and hammers) to exploit precious minerals and metals from the ground. It has been a major source of livelihood to many impoverished local people for more than a century. In many instances, it is the only source of income to indigenous people who have no alternative employable skills. The World Bank estimated that more than 100 million people around the world benefit from ASM which largely occurs in developing countries in Asia, Africa, Oceania, and South and Central America (World Bank, 2013). Cobalt, which is used in lithium-ion batteries to power cellphones, laptop computers, and electric vehicles, is largely produced by artisanal miners in Congo (The Washington Post, 2016). In Sudan, ASM is a significant contributor to the national economy, accounting for about 85% of total gold extracted yearly from 2010 to 2015 (Ibrahim, 2015). Also, according to the Embassy of Sierra Leone in Washington DC, USA, 90% of mineral export in Sierra Leone can be attributed to thriving artisanal diamond mining in the country (Sierra Leone Embassy, 2016). In Ghana, the ASM sector was recognized by government as a multimillion industrial activity, and through a series of initiatives, it was legalized by promulgating the Small Scale Gold Mining Law of 1989 (PNDCL 218). Presently, artisanal mining is widely practiced in two forms: licensed (registered), sometimes referred to as formal ASM, and unregistered (informal or illegal) operations, popularly called “galamsey”, a name believed to have been derived from “gather and sell” by ancient miners who could not communicate in the English language with European/British miners. The ASM sector in Ghana, like other countries, has seen a rise in female participation over the years. A report by the International Labour Organization (ILO) indicated that women account for about 15% of total workforce in ASM in Ghana, and up to 50% in Africa (ILO, 1999). Other researchers have also estimated women participants in ASM to be between 30 and 70% in Africa (Hinton et al., 2003a; Hinton et al. 2003b; Hilson, 2002). Presently, there is no reliable data from Ghanaian authorities on number of females engaged in ASM. However, data obtained from 15 ASM sites suggest that at least 40% of the employees are women. It is expected that a similar trend exists across ASM operations in Ghana."

Jan 1, 2017

By James H. C. Martens

Among the many interesting problems of the pre-Cambrian of the Canadian Shield is that of the origin of certain types of gneisses which are intimately associated with the granites on the one hand and with the metamorphic rocks of known sedimentary origin on the other. The observations recorded in this paper on the structure and composition of these ancient rocks found in a small part of northern Quebec may help to lead to a clearer understanding of the way in which they were formed and also constitute a contribution to the regional geology and petrography of a district for which little detailed information is available. The area considered is located near the Ashuapmuchuan, or Chamuchuan, river about 180 miles north-northwest of the city of Quebec, and therefore well within the Canadian Shield. Although most attention was devoted to the rocks along this river from the 57th to the 70th mile above its entrance into Lake St. John, a few observations on other localities to the north and northwest of that lake will be included. The field work was done in the summer of 1924 in cooperation with L. W. MacNaughton, E. S. Roberts, and B. M. Shaub, all of Cornell University. The party ascended the Ashuapmuchuan river by canoe and spent about a month near the mouth of Stacker, or Brochet, river, the outlet of the lake of the same name, returning by way of Mikoasas river. The writer wishes to express his obligation to his associates for their co-operation in the field and for their permission to publish the results. He is especially indebted to B. M. Shaub for the photographs of rock outcrops. Professor A. C. Gill g:ive many suggestions which were helpful in the laboratory study of specimens and in the preparation of this paper.

Jan 1, 1927

British Coal has made a practical progressive approach to improving the reliability of its mining equipment. Reliability must be addressed at the specification stage but does not end there and routine procedures are used to procure equipment of adequate reliability. The techniques used to monitor and improve reliability during the operational phase of the equipment, providing engineers and operators with detailed printouts, together with the types of maintenance employed, ensure high levels of availability. Finally, the methods of repair and overhaul of British Coal equipment and systems ensure that the initial reliability targets outlined on the specification, can still be achieved.

Jan 1, 1991

By R. G. Johnston

Minerals have many uses in paint systems. These roles include use as primary and extender pigments, sheen control, film durability enhancement, and rheology control. These and other uses of minerals in paints, and the effects of mineral quality variations on coatings performance are discussed. As coatings performance requirements become more demanding, tighter consistency of important mineral properties, such as particle size distribution and purity, is becoming increasingly vital. Future directions of mineral use to meet projected environmental restrictions and performance demands on coatings, including the use of advanced minerals technologies, are examined.

Jan 1, 1993

Optimal drill and blast design is a process often neglected by many underground hard rock mines. This is even more important to the new mine where ring designs need to be implemented and refined in a short period of time. In today's environment where more and more mining is being carried out by contract specialists it is the co-operation between a principal and contractor, who are working towards a common goal, that achieves the highest quality end result. The development of drill and blast designs that cause minimal damage to the mine infrastructure is particularly important to Northparke's E26 Block Cave Mine, as it consists of a single extraction level which must survive intact for the life of the mine. The advanced undercut mining method implemented at Northparkes is fired in a sequence which protects the mine development from potentially damaging abutment stress. This paper details how blast designs will be optimised and sequenced to satisfy the conflicting objectives of maximum rock breakage inside the drill pattern and minimum rock damage outside the pattern.

Jan 1, 1995

By D Connelly

As the resources sector becomes tougher with rising costs and cyclical metal prices, mining companies need to continue to reduce their costs and do more with less. Many new resource projects fail to come in under or on budget based on Feasibility Studies. Particularly, capital expenditure (CAPEX) proves difficult to achieve for resource projects. A number of resource projects have failed because of aggressive plant CAPEX cost cutting resulting in projects with no surge capacity and are unable to achieve design throughput. In addition, the plants are not operable because of the omissions. In recent times many businesses have also experienced the "costs" of simply implementing aggressive operating "cost cutting” measures as a strategy for solving business performance problems. This paper looks at technology driven, employment related, luxury cuts, department cuts and restructuring cuts. In the past companies used an incremental approach based on the use of past budget information as an integral part of the budget construction process going forward. The use of performance reports and Management Information Systems (MIS) is examined along with the role of continuous improvement in achieving sensible cost cutting.

Aug 8, 2011

By W J Fisher

Northern Australia leads in world-class mineral deposits' is a bold statement. First there must be a starting point. Land north of the Tropic of Capricorn (23¦ 26' 5") will be regarded as Northern Australia covering nearly 40 per cent of the land surface of Australia. As opposed to land south of the Tropic of Capricorn, it should be regarded as Tropical Northern Australia and for the sake of brevity, (TNA) Refer Figure 1. Apart from the tyranny of distance from centres of power and population in the temperate zone, it suffered in the past from the belief that the tropics are unsuited for European workers and from the lack of infrastructure. Outstanding mineral deposits of iron, base metals, gold and diamonds, discovered and developed in the past three decades, provided the substance for the title. There are many world-class mines producing and there are mineral deposits neutralised through Government policy. TNA can maintain its lead in world-class mineral deposits provided Government policy will stop partitioning the land and decreasing that available for exploration. Let's look at what we have that is world-class. In Western TNA iron ore deposits at Paraburdoo, Mt Tom Price, Marandoo, gold at Telfer, diamonds at Argyle. In central TNA uranium at Ranger and Jabiluka, lead-zinc-silver at McArthur River, gold at the Tanami, manganese at Groote Eylandt and bauxite at Gove. In eastern TNA Mt Isa, Hilton, Century zinc-lead, bauxite at Weipa, gold at Kidston, Mt Leyshon, magnesite at Yamba and coal mines in the Bowen Basin. Those mines or deposits stand out yet are only an indication of the numerous lesser mines and of mineral deposits depending for development on market demand and/or changes in Government policy, eg 'The Three Mines' policy. Very large areas of mineral rich structures in the western, central and eastern parts of TNA are concealed below flat lying comparatively young unmineralised sediments. The Great Artisan basin sediments in eastern TNA can and do host oil shale and non metallic minerals. Nearly 40 per cent of western TNA is covered by the Great Sandy Desert. The Canning Track, with a series of 54 wells, was constructed by surveyor Alfred Canning in 1908 - 1910 with great difficulty. It extends 1700 kilometres from Halls Creek in the north to the gold town of Wiluna in the south, through the Great and Little Sandy Deserts. Gold explorers are following favourable structures extending to the north east below the sediments and sand hills covering the track. Half of central TNA's mineral structures are concealed by the Tanami desert and the Cretaceous sediments covering the pastoral regions of the Barkly Tableland and the Daly Waters to Top Springs pastoral areas. The Georgina Basin in the south eastern section is part of the concealment.

Jan 1, 1994

By Omid Asghari, Amin Mousavi, Arshad Ranjbar

Geometallurgical modeling of the production benches is an attempt to estimate the geometallurgical variables of the different ore domains, which leads to a better understanding of the ore and its properties. Having geometallurgical variables results in a more accurate prediction of ore characteristics, an improved drilling and blasting operation, and better efficiency of the processing plant. In this research, the geometallurgical variables required for the geometallurgical modeling of the extraction benches are discussed. Then, the relations between Bond work index (BWi), as one of the most important geometallurgical variables and the primary grindability index, and rock geomechanical properties are investigated based on the previously published studies. The BWi is the main parameter for measuring the resistance to the grinding of ore minerals. It represents the energy required for processing (e.g., crushing, grinding) ore rocks in the beneficiation plant. As a real case study, BWi of a production bench in Sungun Copper Mine, located in East Azarbaijan province, Iran, was estimated. The rock’s geomechanical properties were measured using laboratory tests, including uniaxial compressive strength, Brazilian tensile strength, point load strength, and hardness. Then, BWi was estimated using the proposed formulas in the literature and the results of the rock’s geomechanical properties. The selected bench consists of three ore zones and two dyke domains. The laboratory tests revealed that the first ore zone has a slightly higher compressive strength than the other two zones, while the compressive strength of the waste rocks is larger than the ore domains. Using the proposed equations in the literature, the predicted values of the BWi for the samples in ore zones are in the range of 6.36 – 14.44 (kWh/t), and therefore this wide range must be considered when the short-term production schedule is planned. In addition, variations are observed in the samples within a specific zone and between the ore zones, demonstrating heterogeneity in the selected bench. Finally, wide-open results obtained by different equations show a necessity to perform a geometallurgical program specifically for the Sungun mine.

Oct 28, 2021

By V. Králová

The TESCAN Integrated Mineral Analyzer (TIMA), an automated mineralogy system, enables fast and quantitative mineral analyses of rocks, ores, concentrates, tailings, leach residues or smelter products. It combines BSE and EDX analysis for identification and measurement of mineral concentrations, particle size distribution, and liberation/locking parameters. In addition, it can provide bright particle searches for PGM, gold-silver ores, and/or REE. With the newly developed Automated Loading System (AutoLoader), the TIMA has become the world?s first automated mineral analyzer which permits robust, continuous and unattended sample loading. With the AutoLoader (robotics) system, the TIMA has emerged as a powerful plant support instrument. It increases the sample throughput, minimizes manual labor and enables 24/7 operations. As such, it can be used in daily, continuous mineralogy for mine geology/ore control, concentrators, leach operations, and smelter support. It will also increase the capabilities of technical service centers for mining companies, commercial laboratories, large drilling programs or pilot test campaigns. In combination with a highly automated sample preparation lab (sizing, potting and polishing), TIMA technology can establish high-throughput and fast-turnaround automated mineralogy lab modules for mine-site production support.

Feb 23, 2014

By Amy McBrayer, Vladislav Kecojevic, Juan David Valencia Quiceno, Dragan Bogunovic

The mining industry’s commitment to innovation reflects a history of adopting technological advancements to enhance workplace safety, environmental sustainability and vocational training. The objective of this research was to develop an augmented- reality (AR) system for heavy-equipment operators (HEOs) in surface mining. The developed system has the potential to enhance mine safety, training and data-driven decision- making, which presents a significant step toward a more sustainable, effective and technologically driven mining training, contributing to the industry’s evolution and growth. The AR training system leverages Microsoft’s Power Platform and HoloLens 2 capacities to provide operators with detailed and immersive training guides for three mining equipment, including bulldozers, motor graders and haul trucks. AR guides combine speech controls, 3D objects, informative images and explicative videos in the real working conditions to enhance the operator’s learning process. The system has the potential to modify the training structure based on user performance and provides an efficient approach to data collection during training. This project was developed and applied through a case study in a surface mine in the Southern United States.

Feb 1, 2025

By K. R. Griffin

New and developing communication systems enable underground miners to not only connect to the surface from an increased communication coverage area but also to be discovered in the event of an emergency. Communication and tracking systems are required by MSHA regulations, aiming to enhance health and safety and routine production in underground operations. Modeling a mine?s potential communication coverage area will increase overall coverage and efficiency of the communication network itself. Modeling the propagation of wireless communications enables ideal broadcast locations to be found when designing a communications network. Strategic placement of broadcast devices results in a reliable communication network that can better withstand disruption in both daily operation and emergencies. This paper will discuss recent regulatory developments in underground coal communication systems, the implementation of these new technologies, and how communication system?s networks can be modeled and analyzed using computer simulations.

Jan 1, 2010

By Peter F. Howard

The lower Middle Cambrian phosphorite deposits of the Georgina Basin shown in Figure 1 were found in the period 1966-1968 by three companies, namely, International Minerals and Chemical Corporation, Continental Oil Corporation and Broken Hill South Limited. Of these deposits the significant ones are Duchess, Sherrin Creek, D Tree, Lady Annie, Lady Jane, and Wonarah which together aggregate several billion tons reserves of phosphate. Due to the economic factors of freight costs to the coast and softening of the world market price for rock phosphate, none of them is in production, nor is any in the development stage. This paper reviews the historical background to the discovery of these deposits and then deals principally with the discovery of non-outcropping phosphorites in the Barkly Tablelands of Northern Territory by the interpretation of gamma radiation logs of abandoned water bores.

Jan 1, 1971

By M. D. Loy

In addition to products available from private vendors, many useful programs are developed at universities - in fact, many of these programs led the way to commercial development. Other projects are assigned to consultants with backgrounds in system design and mining. Both types of development have led to programs that can be acquired for the cost of a tape or disk. This paper highlights several underground mining packages. These programs consist of: ? USBM model-developed by the United States Bureau of nines. ? PSU model-developed by Pennsylvania State University. ? VPI model-developed by Virginia Polytechnical Institute and State University. ? NUS model-developed by NUS Corp.

Jan 1, 1987

By A Reid, A W. Musk, O Jones

In this paper, the authors attempt to bridge the gap that currently exists between the duty-of-care responsibilities of underground mining industry personnel, and the multifaceted health challenges facing mineworkers in Western Australia’s metal mines where diesel-powered mobile equipment predominate. In addressing this issue, the complexities of the nature and extent of the challenges are discussed along with the current inadequacy of existing regulatory metrics. Support is given to the need for well-organised in-mine baseline studies to clearly define the distribution and aging characteristics of the toxic and carcinogenic pollutants within the mine ventilation system, with special emphasis given to exploring the validity of biomonitoring systems. The paper concludes with the proposal that a template risk assessment data sheet be prepared for the industry to provide mining personnel with a sound basic knowledge of the health risks involved and the control measures and precautions available for minimising and/or eliminating the hazard.CITATION:Jones, O, Musk, A W, Reid, A and Davis, C, 2017. Risk assessment tool for mines using diesel-powered mobile equipment, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 151–154 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By Robert Essler, Paul Marsden, Paul Pandrea

"1. THE VICTORIA STATION TRANSPORT HUB Victoria Underground station is part of the Victoria transport hub, which comprises one of London’s main train termini and a major bus station. At the Underground station, the District Line running in the older shallow brick tunnels dating back to 1868 cross the Victoria Line running in the lower tunnels, which were opened in 1969. After Waterloo, Oxford Circus and King’s Cross/St. Pancras Tube stations, Victoria is the most frequented station on the London Underground network and is used by over 80 million passengers per year. Capacity at Victoria Tube station has been inadequate for many years with passenger numbers steadily rising. Overcrowding is a constant challenge and the station has to be closed regularly during morning and evening peaks until sufficient trains pass through to clear the platforms. For this reason an extension has been debated since the 1990s. After intensive preliminary investigations and feasibility studies covering many variants, which included a large-scale jet grouting test to determine the applicability of this technology as a protective measure for the tunnelling works, the project was officially started with the Victoria Station Transport and Works Act Order (Secretary of State, 2009) effective on the 18th of September 2009. Following a competitive tender process a joint venture of Taylor Woodrow and BAM Nuttall were awarded the contract by London Underground, with their design being carried out by Mott MacDonald Ltd. Ensuring the busy station remained open to the public was a key requirement of the Victoria Station Upgrade. Jet grouting works, which were executed from ground surface, were also carried out while the station was fully operational 2. OVERVIEW The Victoria Station Upgrade aims to increase the capacity of the Underground station significantly and one of its major design objectives is to optimise the transfer between the Underground lines. In order to achieve this, the following new structures are currently under construction: •,A new North Ticket Hall •,Extension of the existing South Ticket Hall •,Nine new escalators •,Connecting tunnels between the North and the South Ticket Hall •,8 new lifts providing step free access to all platforms •,An improved connection between the rail/bus terminus and the Underground station As the elevation and geometry of the existing structures cannot be changed, the new structures need to be adapted to the existing structures (see Figure 1)."

Jan 1, 2016

By Zongliang Zhang

Electrowinning is a significant step in metal extraction processes. Because the nature of electrowinning is to reduce metal from its oxidized state, substantial energy consumption accompanies it. Electrowinning processes of different metals have much in common—the deposition of the metal on the cathode and the counter-reaction on the anode. An advanced model was developed that can be applied to a variety of metal electrowinning processes. A model for specific metals can be readily obtained by modifying parameters such as potential, kinetics, and side reactions in the model. The model incorporates mass transfer, gas-liquid flow, electrochemistry, and deposition, making it a comprehensive electrowinning model. The model is applied to copper, nickel, and zinc and verified with the experimental results. In addition, the parameter settings and results of different metals were compared, showing that this model has great versatility and accuracy, thereby making it an efficient and effective research tool.

By M Simanjuntak, A M. Supomo

PT Freeport IndonesiaÆs copper/gold operation disposes of approximately 222 000 dry metric tonnes of tailings per day via two thickeners. Reduction of the flocculant dosage rates in each of the tailing thickeners has been achieved with the installation of Clarometers«, modifications to the existing operating DCS control strategy and a change in plant flocculant. This has reduced the flocculant consumption rate in the last twelve months by approximately 20 per cent. It has also highlighted the disparity in the settling rates of the two thickeners. Collaborative efforts between Cytec technical site engineers and Freeport operational personnel have made possible the overall gains achieved in the tailings thickener optimisation.

Jan 1, 2003

By A D. Campbell, G R. Power

The increasing availability of marker data in sublevel caving operations is changing the way draw can be managed to achieve positive recovery outcomes in these mines. This paper describes how marker data has been incorporated into flow simulations to help calibrate full mine ore recovery simulations for the forecasting and optimisation of recovery.Some flow modelling techniques do not use marker data, relying instead on the outcomes of physical and numerical experiments to guide assumptions about an idealised recovery flow shape. Other mines have access to marker trial data, but find it difficult to specifically link this marker trial information to their recovery models. This can make it difficult to create a link between the marker trial information and recovery forecasting and limits the potential value of the marker trials at the mine.In the simulations shown here, the marker rings are fully incorporated into the flow model, and can be tracked in the model. The model is compared against the real underground marker recovery information to give the user an indication of how accurately the flow settings in the model are reflecting the conditions in the experimental marker rings. An example of use of this system at an operational mine is included.CITATION:Power, G R and Campbell, A D, 2016. Modelling of real-time marker data to improve operational recovery in sublevel caving mines, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 105–110 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By D. N. Madge

A description will be given of an approach to plant process automation based on the strategy of first developing an information system followed by later development of process models. The advantages of this approach over the unit process control will be outlined. Some insight will be given into the risks associated with this method. These risks can be shown to be primarily economic.' Some reference will be made to two Cominco installations in the interests of illustrating the generality of the information systems approach.

Jan 1, 1972

By B Vorster, T Medhurst, A Huey

Roof conditions at Oaky North Mine can be prone to stress related damage and/or time dependent degradation. The ability to identify these areas prior to mining has proved challenging using traditional methods. To help alleviate this situation, a study was initiated to investigate methods for roof characterisation using geophysical logs. This involved the use of neutron log data to provide an indirect measure of the proportion of carbonaceous/micaceous laminae present in the immediate roof strata. Detailed analysis of the shale–porosity inter-relationships arising from this analysis provided a means to estimate the proportion of laminations for a given roof interval. This paper outlines the process and how it was used to improve the current GSR modelling and hazard mapping process.

Nov 29, 2022