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By A. Adu-Acheampong

A geotechnical study was conducted to identify the cause(s) of stope instability at the Ashanti Mine (Obuasi, Ghana). As part of the investigation, laboratory testing of rock was performed and the rock mass was classified according to the Q-System (Barton et al., 1974).Numerical analyses were performed using the computer program FLAC (Itasca, 2001). The observed failure zone around the stopes was simulated using both Mohr-Coulomb and Hoek-Brown (Sheorey,1997) models. Yielding along peripheral graphite bands and tensile failure were clearly identified to be the major contributors to stope instability.

Jan 1, 2003

By H. Ehnes

"“Industry 4.0” – “Mining 4.0” - perhaps you have already heard of these terms? These keywords signify the next stage of industrial production. The internet and production technologies are growing closer together. Machines can communicate with one another, wherever they may happen to be located. The “Internet of Things” is the appropriate term. But what does SAFETY 7.0 mean? It is both brand new and traditional at the same time. It also has to do with the success of companies, with efficient production. And yet there is a great deal more at stake. It has to do with our lives and our safety – the supreme commodity in this world. What exactly SAFETY 7.0 means, what the number 0 stands for and the meaning of the number 7, and what this all has to do with mining will be explained in the following article. Mining is a fascinating undertaking. Mining is indispensable for a country’s economic development, whatever that may concern: infrastructure, energy supplies or raw materials for industrial production. Mining has brought forth many technological developments and innovations that can currently be found in our daily lives. Mining is impressive, grandiose and repeatedly fascinates mankind with its immense dimensions. Miners throughout the world still work hard and, for this reason, are bound to one another in a special way. In mining, every man looks out for the other; you have to be able to rely on each other. That creates a strong bond. The other side of the coin is that mining and disasters belong to normality in the media and thus also in our perception. Accidents at work and even catastrophes occur in mining, quarries, or raw material operations almost on a daily basis somewhere in the world. They are often associated with extremely serious injuries, or even a fatal outcome, for the miners affected and, in turn, dramatic consequences for the families of those involved. It could be in China, India, Russia, or somewhere in Africa, Asia or America – it mostly does not happen in front of our door or in our neighbour- hood. Perhaps because of this in the daily concert of negative headlines, we do not register these catastrophes any more in our minds. We write them off under the heading “Nothing special”, since there are, day in day out, more terrible news items about wars, civil wars, famines, or ecological disasters. Things only really change if there is a dramatic number of deaths or when we are personally affected, close by in the vicinity, or can witness the rescue action live. In Europe, these three mining disasters in particular have recently generated media resonance:"

Jan 1, 2016

By T. Gonzales

Magma Metals Company operates an Outokumpu Flash Furnace, four Peirce-Smith Converters and two Anode Casting Wheels supported by six Anode Vessels. Process gasses from the Flash Furnace and Converters are treated in a two train/double contact sulfuric acid plant. Sulfur capture for the smelter is +98%. The new flash furnace was commissioned on July 7, 1988 and has processed over three million tons of sulfide concentrate without a major rebuild. Magma has gained unique experience in the operation of the flash furnace at high oxygen enrichments with low off-gas dust loadings. New procedures have been developed to maintain secondary material generation at equilibrium and for maintaining metallurgical control of operating parameters. This paper describes all the procedures, operation control parameters and operating philosophy that has allowed Magma to achieve superior performance.

Jan 1, 1992

By M. Scaggs, K. Phillips

"Coal Worker’s Pneumoconiosis (CWP) is an occupational lung disease caused by chronic exposure to respirable mine dust. After decades of steady decline, CWP incidence appears to be on the rise since the mid-1990s, particularly in some regions of Appalachia. Alarmingly, many of these cases have rapidly progressed to the most advanced form of CWP, referred to as Progressive Massive Fibrosis (PMF). Most of what is currently understood about respirable mine dust has been gleaned from routine regulatory monitoring, which tracks total mass concentration of respirable dust (mg/m3) and, less frequently, silica mass content. This paper focuses on the use of thermogravimetric analysis (TGA) as a way to provide basic characterization of the whole composition of the dust, allowing it to be classified into three mass fractions – coal, carbonate, and non-carbonate minerals. TGA was conducted on 59 dust samples collected by miners from eight coal mines in central Appalachia, and the results are discussed in terms of differences between mines, regions, and primary occupations. Consistent with prior results on area dust samples from some of the same mines, results of the personal samples generally show that the coal mass fraction of the dust is relatively low. Carbonate and non-carbonate minerals thus tend to make up the bulk of the dust mass, and vary across occupations and specific mines. INTRODUCTION After nearly four decades of decline, the prevalence of Coal Workers’ Pneumoconiosis (CWP, or “black lung”) in the US has been on the rise since the mid-1990s (Laney et al., 2014; Laney et al., 2010; Suarthana et al., 2011; Pollock et al., 2010; Antao et al., 2005; Blackley et al., 2016). Particularly alarming is the number of cases of progressive massive fibrosis (PMF), which is the most advanced form of the disease (Pollock et al., 2010; Antao et al., 2005; Blackley et al., 2016; Laney et al., 2017). A recent study by Laney et al. (2017) observed 192 US coal miners participating in the Coal Workers’ Health Surveillance Program (CWHSP) who had been diagnosed with PMF since 2000. Of the 163 (85%) that had a normal radiograph on file to use as a baseline, 27 (17%) of these individuals had progressed from a normal radiograph to PMF diagnosis in less than 10 years. Moreover, 162 (84%) of the individuals in that study worked in KY, WV or VA, and 169 (88%) had only ever mined underground. Blackley et al. (2016) also reported on a group of 60 PMF cases that were discovered by a single black lung clinic in eastern KY. Since seeking care at such clinics and participation in the CWHSP are voluntary, and could be influenced by a number of factors, these recent reports may well overestimate the degree of resurgence in severe disease (i.e., versus disease that was previously under-reported). Even so, they highlight a critical need to better understand the cause(s) of disease development and progression – such that effective interventions can be devised."

Jan 1, 2018

By K. H. Nimerick

A unique freeze conditioning agent (FCA) which functions by forming structurally weak ice rather than suppressing the freezing point of water has been successful in alleviating frozen coal problems. Frozen coal treated with FCA has been quickly unloaded at temperatures below -17.SoC (O°F). Other areas where FCA has found utility has been de-icing conveyor belts, idler, idler arms and other moving parts that have been impeded by ice.

Jan 1, 1977

By R. E. Cook

"Mineral deposits require substantial amounts of energy to transport and be processed into usable form and, as such, present a real processing challenge in that the deposits are never homogeneous and orebody compositional characteristics are all over the map. Extracting the desired mineral(s) from the deposit at sufficient profit margin, despite severe fluctuations in market price, requires process automation architecture capable of supporting an integrated enterprise solution. Such an architecture will encompasses the activities of individuals, process units, process areas, plant level activities, mine management and business planning, and accounting systems. Key to the automation process is the aspect of value generation. This article brings together the various requirements for the automation of a mining enterprise and presents the different aspects of how to obtain value across the entire mining operation.Minerals’ processing sites are historically long lived, with 20-year life-of-mine not uncommon and 75 years not unheard of. Considering that hardware technology advancements are introduced every six months, or less, it is prudent to select process automation systems that adhere to “open” industrial standards versus proprietary based systems. In the minerals processing industry, the key to survival is driving the cost of production per unit volume to the lowest possible level and provide enough profit to sustain operations. Control system architecture and business information technology are rapidly becoming important tools in the quest for productivity. Getting key dynamic business performance information at the right time to the right person or process unit is crucial to successfully achieving corporate goals. The process automation architecture selected must, therefore, be able to integrate to the various networking enterprises and business systems.The mining industry is generally known as an extractive industry that is physically oriented with respect to operations and the activities in which workers engage. Large numbers of people performing manual tasks in difficult surroundings, produce variable outputs. But times are changing – and so are industry best practices. While the nature of work still consists of activities such as ore extraction, ore movement, ore concentration, refinement and logistics, automation innovations are starting to change the nature of many of the production steps. The industry has transitioned from requiring more physical activities by workers to more information management, automated control and collaboration within the operation. Humans are good at situational intervention and nonlinear reasoning and do best when empowered with an overall production perspective. Machines and automation are good at repetitive functions, steady state operation, and managing transitions. Thus, a combination of advanced technology solutions, reliable and useful information and full human contributions are necessary to mining operations for value generation."

Jan 1, 2015

By Matthew T. Mowry

As the mining industry continues to hire young professionals to supplant the growing number of retirees, a well-developed engineering curriculum, coupled with practical, real-world training, can prepare mining engineering graduates to make meaningful contributions in the industry. Successful companies can be measured not only by their reserve base and annual production but also by their retention of mining engineering graduates with zero to five years of operational experience. My personal experience in the industry during the last five years has been varied and rewarding. The knowledge and experience I have gained have taught me valuable lessons that prepared me for my current role.

Nov 1, 2013

By Miche1 Dagbert

In most open pit operations mining porphyry type deposits, production planning rests on an are reserve inventory block file which is derived from diamond drill hole data. With such a practice, the way by which block values are generated is critical and in the recent years many studies deal with the comparison of different estimation methods for block grades (Mueller, E. (1), Knudsen et al (2) (3), Barnes, (4), Williamson and Mueller (5). Typically in such studies, one selects a bench or a group of benches where there is a "sufficient" number of blast holes (BH) with assay values in each of the blocks (generally 30.5 x 30.5 m (100 x 100 ft) or 15.2 x15.2 m (50 x50 ft). Then the arithmetic mean of the BH values in each block is computed and it is assumed to represent the real block grade against which different estimated values are compared. However it is sometimes observed that the variation of these BH values within a block is high and that their arithmetic average may significantly differ from the real average grade of the block (Barnes (4). The problem of the precision of the mean BH grade in a block has been examined by Williamson and Langlois (6) in an experimental way. They strove to find a better estimate of the average block grade than the mean BH grade but their results were not conclusive. The purpose of this study is to investigate the same problem within the frame of geostatistical models (David (7). Besides practical results obtained with these models, two general points are emphasized and illustrated in the text. First, "good results" are obtained if "good geostatistics" is done (David et al (8).

Jan 1, 1978

By Carrie Smith

The Society for Mining, Metallurgy & Exploration’s annual conference and expo, MINEXCHANGE 2026, will take place Feb. 22–25, 2026, at the Salt Palace Convention Center in Salt Lake City, UT. The event will foster a hub for innovation, technical exchange and policy discussion for the global mining industry. Over four days, attendees will take part in short courses, technical sessions, field trips and networking events that highlight the advancement of the mining industry. The conference’s keynote session, titled “Regaining America’s Mineral Dominance,” will start at 8:30 a.m. on Feb. 23 in the Grand Ballroom E–J. The speaker will address the sweeping policy actions now shaping the nation’s mineral future, following a series of executive orders issued by the Trump administration designed to bolster domestic mineral production and energy security. These directives, including Immediate Measures to Increase Domestic Mineral Production (EO 14241) and Establishing the National Energy Dominance Council (EO 14213), have set in motion a coordinated effort across the Departments of Interior, Energy, Defense and Commerce to enhance the United States’ position as a global leader in critical minerals. The invited speakers include Utah Governor Spencer J. Cox and Nate Foster, managing director of Rio Tinto Kennecott, who will examine how policy and industry are converging to meet surging demand for minerals essential to modern technology. Governor Cox is expected to highlight Utah’s long-standing role in American mining, from the early development of Kennecott Copper to its current position as a producer of 40 of the nation’s 50 identified critical minerals. Foster, meanwhile, will offer insights into Rio Tinto’s extensive operations in Utah, including the Kennecott Copper Mine — one of only two operating copper smelters in the United States — and the company’s ongoing efforts to build more resilient, sustainable supply chains. Rio Tinto’s work in critical mineral production, from copper and tellurium in Utah to new operations in Arizona, has made it a fundamental figure in the U.S. mineral economy. Projects such as the Resolution Copper development and the revival of Gunnison Copper using Rio Tinto’s innovative Nuton technology illustrate how private-sector leadership is driving sustainability in domestic mining. These advancements come at a critical moment for the industry, as copper prices remain near historic highs. The keynote session will emphasize that meeting future mineral demand will require a concerted effort between government, industry and technology partners to secure responsible, domestic production. Immediately following the keynote, the Robert E. Murray Innovation Award Lecture will start at 10 a.m. as part of the same session. Lucy England, managing director at FLSmidth, will present on “Sustainable Copper Mining Flowsheets and the MissionZero Mine.” England, who has spent more than 25 years in mineral processing and innovation, will discuss how FLSmidth’s MissionZero initiative aims to develop the world’s most efficient

Feb 1, 2026

By B. R. Waples

Sometimes a project is born easy, sometimes a project has a hard time being born. Probably every project can say we had tremendous problems to overcome and they would all be right. This project had all things happen to it. Born easy, a hard time after being born, there were tremendous problems to overcome but here it is, a major copper project, a major operation, and a new source of copper for Mexico and the world market. La caridad is an ore body located in the state of Sonora in northwestern Mexico. It is at an elevation of 1,200 meters above sea level and the nearest major city is Hermosillo, the capital city of Sonora. Hermosillo is located approximately 270 kms (about 168 miles) to the southwest of la caridad. North of la caridad, 130 kms (about 81 miles), is the U.S. border town of Douglas, Arizona, which has a sister city on the Mexican side of the border -Agua Prieta.

Jan 1, 1979

By Jamal Rostami, Mark Board, Clayr Alexander, Muthu Vinayak Thyagarajan

In the past several decades, many major equipment manufacturers have ventured into developing new technology for underground hard rock excavation. This includes variety of configurations for full and partial face mobile excavation units. Mining industry prefers machines that can excavate noncircular, flat invert profiles and be able to make tight turns in hard rock. The need to use disc cutters for cutting hard rock has impeded the development of such machines due to the need for gripper system or large mass of a machine to support the force requirements of the disc cutters. Most of the prior attempts have been partially successful and the operations have faced some practical limits and challenges. Among the units that have been successfully used, one can name mobile miner, which was used for rock excavation in some projects. A redesigned mobile miner, called the “Remote Vein Miner,” or RVM, has been developed by Epiroc for underground hard rock mining in Hecla’s Lucky Friday Mine. This equipment potentially opens numerous opportunities for innovation in civil tunneling projects, where the operational flexibility and accessibility of a TBM’s limited tunnel path, design of the profile, and cost are limiting factors. This paper explores the application of the RVM in tunneling projects, its advantages and possible areas of innovation in tunnel planning and design.

Jun 13, 2021

Just 104 km (65 miles) from Phoenix, AZ, Rio Tinto hopes its new Resolution Copper Mine will be a showcase for the Rio Tinto management philosophy. Its goal is to have a net positive impact. In every place that Rio Tinto mines, it wants to be able to have an overall beneficial effect on the local community, environment and economy. ?We?re constantly working to understand our impacts, to understand how to minimize our impacts and understand how to mitigate those impacts,? said Resolution Copper Mining chief executive officer David Salisbury, from the global headquarters of Rio Tinto Minerals in Green-wood Village, CO.

Jan 1, 2010

"One of the major issues that the Rare Earth Elements Mining Industry has to deal with is the legislation vacuum that exists in many countries around the world. Among these, are countries which have long history and tradition in mining. In many cases the lack of direct legislation for REE mine management as well as for other potentially polluting industries can be a barrier to sustainable development. Moreover, the case of lax legislation in China has led to environmental pollution problems and extended smuggling of rare earth elements. This paper looks into the current regulatory status on the mining of REEs, identifies the loopholes and suggests some elements for a new global legislation framework for sustainable development in the REE mining industry. The setting of this regulatory framework will be in line with the present and future challenges of the rare earths market as well as with the policy strategies that are defined internationally. The aim of such a legislative framework will be to strengthen the global rare earth elements supply chain, appease social concerns and ensure the preservation and conservation of the environment. INTRODUCTION The general public received their first introduction to rare earth elements (REEs) in 2010, when the previously inconspicuous commodities became the subjects of front-page headlines. It was when China created a furore in global high-tech markets after imposing an embargo on Japan following a minor marine dispute (Barakos et al. 2015b). Soon enough the Chinese embargo was extended on REE export restrictions all over the world and thus aroused concerns to many countries over potential supply disruptions. The world had suddenly realized that these wonder materials underpin products that they care about. Governmental and industry executives, policymakers and material scientists voiced concerns and conducted numerous reports stating the situation and the risks of a supply crisis. The price spike of 2011 intensified the crisis and the public turmoil, yet the drama did not last for long as the prices declined significantly in 2012. Nevertheless, the world was nonplussed by the fact that China has the total control of the market with more or less the 90% of the global production. More potential entrants became interested, thus initiating an exploration boom during the recent years that has resulted in a significant increase in known global REE reserves that could have potentials for exploitation."

Jan 1, 2016

By William J. Bryson

Just picture, if you will, the hot, lonely and desolate Ochre Mountains west of Salt Lake City. There works a grizzled old miner, his boots worn down, his clothes hang on a body stooped by years of hard labor. His skin is wrinkled and leather toughened by many years in the hot desert sun. His ever faithful burro stands patiently in the shade of a large rock as the tired old miner examines ore samples just acquired that very morning. Suddenly the old man's eyes widen, his breathing becomes rapid. 'Leaping to his feet, with a gleam in his eye, he cries, "Eureka, I'm rich, I've found the mother lode. This is where I will start my digging. " Without warning, the silent wilderness is alive with wild, shouting, charging figures! Frightened the old miner glances about him wide-eyed and pan- icky. His heart sinks, dismayed he now knows all is lost, this is the end. For there leaping from behind rocks and brush papers in hand, are the men from the Department of Interior, Bureau of Land Management, State Mine Inspectors, OSHA, MESA, EPA, OEO, and the never ending list of regulatory bodies related to todays mining industry.

Jan 1, 1975

Ground falls (roof and rib) have historically been responsible for nearly 50% of all fatalities in bituminous underground coal mines. In recent years, the number of some annual ground fall fatalities has approached zero, indicating that significant progress has been made. On the other hand, the twin disasters at Crandall Canyon in 2007, in which nine miners perished in violent coal bumps, provided a stark reminder that complacency is premature. One important success has been a great reduction in the number of miners killed inby roof supports. Throughout the 1990s, these accounted for nearly half of all roof fall fatalities, but there have just been two inby incidents since 2005. Progress has also been made in pillar recovery, where there has been just one fatal incident since 2005. On the other hand, more than 300 miners continue to be injured each year by rock falling from between supports and 100 more are injured by rib falls. Together, these two categories also account for a large percentage of recent ground fall fatalities available technologies such as roof screen, rib bolting and inside control roof bolters could reduce injury and fatality rates if they were used more widely. Further advances in these areas will likely be the next big advance in ground control safety.

Jan 1, 2011

By R. A. Haney

The Mine Safety and Health Administration (MSHA) has conducted studies both in coal and noncoal mines to evaluate methods for sampling and separating diesel particulates from mineral dust aerosols. The agency is investigating size separation techniques to distinguish between diesel particulate and respirable coal mine dust. Additionally, ashing techniques have been used to distinguish diesel particulate from mineral dust in metal and nonmetal mines. As part of these studies, personal exposures to diesel particulate for various mining occupations have been measured. This paper describes the measurement techniques and summarizes the exposure levels for various underground mining operations.

Jan 1, 1990

By M. Bunch

"THE SUPER CYCLE IS GONE The utopia of the rising sales volume, for mining companies from 2002-2011, was entirely due to rising production volume and prices. The Australian mining sector experienced an 18 percent annual growth rate in revenues, and 11 percent growth in prices. (1) However, EBIT remained flat during the same time period. In addition, Australian mines saw a 7 percent annual decline in both labor and capital productivity. (2) Mines in the U.S. and Canada produced similar results, whereas the world-wide mining industry has seen a productivity drop of 40% since 2001. (3) The decade “Bull Run” of rising prices was trashed by companies that chased low-quality assets while increasing debt on their balance sheet. It seemed everyone believed the “super cycle” would last forever, while completely ignoring the history of cycle downturns. Worldwide mining operations are as much as 28 percent less productive today than a decade ago, according to new McKinsey research. The results from McKinsey’s new MineLens Productivity Index (MPI), which adjusts for declining ore grades and mine cost inflation, show that the pronounced decline in productivity is evident across different commodities and is seen in most mining players and geographies. (4) McKinsey sees three important areas of focus to address the root causes of productivity decline. 1) Embed effective management operating systems at mines 2) Prioritized operational excellence and capabilities development 3) Focus on innovation Reality has now settled back in and companies are struggling to make ends meet. The basic management staple of controlling costs and improving the production/productivity that was lost in the excitement is now back in play. Traditional cost-cutting approaches, such as across-the-board spending cuts, layoffs, and hiring freezes are only short-term initiatives and will not permanently improve a company’s cost structure or improve long- term competitiveness. This can only be accomplished by engaging front-line employees and empowering them to make necessary improvements in their daily work. It is time for leaders to lead and develop cultures of continuous improvement within their organizations in order to sustain their mining project to the end of mine life. Successful operating managers require two different skill sets of Leadership and Management; knowing how to lead people in their organization and how to manage the work they do."

Jan 1, 2016

By Harold Bloom

Dimethylglyoxime reacts with nickel in a buffered ammonical-citrate solution containing the detergent ?Aquet? and hyroxylamine-hydrochloride. The resulting nickelous dimethylglyoxime is extracted with xylene. Visual comparison with standards permits the estimation of from 50 to 10,000 ppm of nickel. Soil, rock, or sediment may be decomposed by digestion with (1-3) nitric acid, allowing about 70 determinations per man-day to be carried out. With minor modifications to the above procedure, sediment and soil may be semi-quantitatively analyzed for nickel at the sample site. The chemical equipment is easily portable and the analysis extremely rapid because the buffer, dime thylglyoxime and xylene are added simultaneously to the sample and no heating is required. The sensitivity varies with the "availability" of the nickel ions; under favorable conditions, one may obtain a positive test for as little as 10 micrograms in soils and sediments. This procedure is similar to one, for the field determination of heavy metals described elsewhere by the author.

Jan 1, 1958

In the grand scheme of things, the 9.5-t (21,000-lb) shipment of molybdenum concentrate that left Freeport-McMoRan?s Climax Mine site on May 10, 2012 was not unlike the thousands of others that have been hauled away from the site during the last century, except for the fact that this shipment marked the official rebirth of one of America?s greatest mines. For nearly two decades, 17 years to be exact, there was no production from the mine that was once the largest underground mine in the world and was so important to the Allies? effort during World War II that it was assigned the highest priority of any mine in the United States by the War Production Board. The economic recession in 1980 put an end to the mine?s success, and the Great Recession of 2008 nearly derailed the mine again. But, like the nearby town of Leadville, CO, the mine survived thanks to an investment of more than $700 million by Climax Molybdenum Co., a Freeport-McMoRan company, to bring the Climax Mine back into production.

Jan 1, 2012

By F. L. Wilke

A model is presented to minimize the winning costs per shift within the different sections of a potassium mine by liner programming and to simulate the other areas to get all costs in order to comp re different production strategies. he model is based on a a given total layout of the underground mining which is considered to be fix during the planning period. Room-and-pillar mining is assumed to be used. Potassium extraction is done by drilling and blasting. Transportation of the raw material to sectional crushers is done by scoop-trams where it is crushed to coarse-grains which allow further transportation by conveyor belts to the hoisting shaft or to a bunker. When production is stopped, the continuously working factory is supplied by means of this bunker. Starting from a desired composition of the raw material the model has to keep the given total. demand of raw material per shift, to minimize the winning costs, to keep the capacity constraints of the equipment and to determine the planned output of production of the sections per shift. Costs of the areas which follow the extractions are added to extraction costs in order to allow a comparision of costs of several alternatives of production. Optimization in extraction and assignment of scoop-trams to sections is done by linear programming. The other areas of the mine are treated by simulation. The model output is a schedule of the calculated costs broken down into costs of processes, equipment, and kinds of costs. This proceeding enables to compare different ways of production.

Jan 1, 1979