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By Moraka N. V., van Rensburg M. Jansen

"SynopsisGoing beyond transformation claims contained in employment equity scorecards and industry compliance reports, this article provides qualitative insight into the initiatives employed and challenges experienced by mining companies in a quest to transform the mining industry. Perceptions expressed during in-depth interviews with 10 senior executives showed that the assumption that mining companies are reluctant to transform is erroneous. Results from this study suggest buy-in and commitment to transformation. This article describes specific initiatives undertaken by mining companies to transform. The most notable initiatives include staff recruitment efforts to appoint historically disadvantaged South Africans (HDSAs), staff development initiatives, as well as community development. The findings furthermore contextualize the challenges experienced by industry participants in their quest to transform. Despite accusations that industry participants are not taking responsibility for the implementation of the transformation agenda, government needs to recognize that they too have a role to play and need to appreciate and assist in the current challenges experienced by the industry.IntroductionWe need a mining sector that works. Mining employs over half a million people. It is the biggest earner of foreign exchange in our country. It also contributes about 20 billion rand directly to tax revenue. Mining also makes a far larger contribution as a buyer of goods and services, and a supplier of inputs to other sectors of our economy and other economies around the globe’ said President Jacob Zuma during the 2014 State of the Nation Address (Zuma, 2014). However, despite apparent commitment from government, enforced compliance with social and labour plans, regulations and Mining Charter targets, the South African mining industry is slow to gain local and international investor trust (Deloitte & Touche, 2013; Mashego, 2013).Industry players acknowledge that their context has changed – creating various challenges (Davis, 2014). In the past few years, such challenges included subdued commodity prices, increased working costs, constrained infrastructure, and high labour costs, coupled with poor levels of productivity, strained labour-management relations, an uncertain regulatory environment, and the inevitable maturation of the industry (Deloitte & Touche, 2013; Davenport, 2014). Mining affected communities also became more cognisant of their rights, and politicians more vocal in their expectations from their relationships with the mining giants (Davis, 2014). One of the main issues that contributed to the difficult operating conditions was claims from organized labour and Minister Shabangu that this industry is too slow to transform. Specific claims were made in terms of employment equity, fair salaries and wages for mineworkers, housing and living conditions, health and safety issues, and general working conditions (Limpitlaw et al., 2005; Miningmx, 2013; Shabangu, 2010). These claims were followed by what Gill Marcus, Reserve Bank Governor, explained as ‘unprotected strike action [that] has escalated into an uncontrolled, violent and unlawful landscape, led by a mob mentality in the absence of formal and recognised leaders’ (Mavuso,2013)."

Jan 1, 2015

By B. Caro Vargas

The Toulon Tunnel project is a key component of the highway corridor on the French Riviera between Marseille and Nice and is a fundamental transportation infrastructure for the region. The first design studies started in the 1960s. The tunnel project is comprised of two separate tunnels: south and north. The north tunnel was built between 1992 and 2002 after 10 years of difficult construction. On March 15, 1996, for example, a collapse of the tunnel in the Marchand area generated a sinkhole in the city center, causing a 20-month delay. The south tunnel alignment runs parallel to the north tunnel below Toulon?s historical downtown at a depth of 20 to 40 m (65 to 131 ft) with some areas with less than 10 m (32 ft) of cover. The risk management program was studied to be a state of the art program in urban tunneling construction.

Jan 1, 2012

By Jean-Michel Rendu

That you are giving the Daniel C. Jackling award to me is a great personal honor. But more significantly, it is a recognition that geostatistics has come of age. And since I am considered by many as belonging to an older generation of geostatisticians, I thought that it would be fitting that I reflect on where geostatistics came from and where it might be going. First, though, let me propose a definition of geostatistics. Etymologically, paraphrasing Webster's definitions of "geo" and "statistics," it is "a branch of mathematics dealing with the collection, analysis, interpretation and presentation of masses of numerical data taken from the earth." This definition is most appropriate in the context of mining geostatistics. It includes both classical and spatial statistics. It emphasizes the earth aspect, or the analysis of geologic features. And it should remind the practitioner that geologic input is a critical part of all geostatistical applications. In the 1910s, statistical methods were already used to analyze geological data. However, the origin of geostatistics, as we know it today, is best set in the late 1940s, when H.S. Sichel recognized the lognormal distribution of sample values in the South African gold mines. In 1951, Daniel Krige observed that "it can be expected that the gold values in a whole mine will be subject to a larger relative variation than those in a portion of the mine." In other words, samples taken close to each other are more likely to have similar values than if taken farther apart. This observation is the foundation on which spatial statistics, which characterizes values defined in a multidimensional space, is built. However, the 1950s were marked by studies based on classical, as opposed to spatial, statistics. It was only in the 1960s that the need was recognized to model the similarity between sample values as a function of the distance between samples and that the semivariogram was defined. A theoretical framework was developed by Matheron that supplied an elegant mathematical explanation to the empirical observations made by Krige. Matheron coined the term "kriging" in recognition of Krige's pioneering work on the geostatistical evaluation of mineral deposits. As soon as this theoretical framework was developed, it was possible to bring geostatistics to the academic world. The "Centre de Geostatistiques" was founded in Fontainebleau. Numerous students were trained there, disciples eager not only to improve the theory and develop more sophisticated mathematical tools, but also to spread the new faith throughout the world. Expansion of geostatistics exploded in the 1970s, arguably the most fertile decade if it is judged by the frequency of theoretical breakthroughs, the number of original publica-

Jan 1, 1995

THERE are three objectives in translation of works of this character : to give a faithful, literal translation of the author's statements ; to give these in a manner which will interest the reader ; and to preserve, so far as is possible, the style of the original text. The task has been doubly difficult in this work because, in using Latin, the author availed himself of a medium which had ceased to expand a thousand years before his subject had in many particulars come into being ; in consequence he was in difficulties with a large number of ideas for which there were no corresponding words in the vocabulary at his command, and instead of adopting into the text his native German terms, he coined several hundred Latin expressions to answer his needs. It is upon this rock that most former attempts at translation have been wrecked. Except for a very small number, we believe we have been able to discover the intended meaning of such expressions from a study of the context, assisted by a very incomplete glossary prepared by the author himself, and by an exhaustive investigation into the literature of these subjects during the sixteenth and seventeenth centuries. That discovery in this particular has been only gradual and obtained after much labour, may be indicated by the fact that the entire text has been re-typewritten three times since the original, and some parts more often ; and further, that the printer's proof has been thrice revised. We have found some English equivalent, more or less satisfactory, for practically all such terms, except those of weights, the varieties of veins, and a few minerals. In the matter of weights we have introduced the original Latin, because it is impossible to give true equivalents and avoid the fractions of reduction ; and further, as explained in the Appendix on Weights it is impossible to say in many cases what scale the Author had in mind. The English nomenclature to be adopted has given great difficulty, for various reasons ; among them, that many methods and processes described have never been practised in English-speaking mining communities, and so had no representatives in our vocabulary, and we considered the introduction of German terms undesirable ; other methods and processes have become obsolete and their descriptive terms with them, yet we wished to avoid the introduction of obsolete or unusual English ; but of the greatest importance of all has been the necessity to avoid rigorously such modern technical terms as would imply a greater scientific understanding than the period possessed. Agricola's Latin, while mostly free from mediaeval corruption, is somewhat tainted with German construction. Moreover some portions have not

Jan 1, 1950

By Nicholas G. Theofilos

The Bahamian economy weathered the worldwide recession of the last few years better than most developing countries. This was mainly owing to the ties between the tourist industry of the Bahamas and the U.S. economy. The mineral industry played a minor role in the country's economy. The chief mineral exports included an increasing amount of petroleum products horn the country?s 500,000-barrel-per-day refinery, steel pipe, salt, and aragonite. A 60,001)-barrel-per-day desulfurization facility was completed by Bahamas Oil Refinery Co. (BORCO) in Freeport. The project included vacuum gas oil desulfurization, hydrogen and sulfur recovery, steam generation, water desalinization, and offsite facilities.

Jan 1, 1980

By A. C. Legg, M. T. Malema

Keywords: Pyrometallurgy, flash, smelting, furnace, nickel, copper, Botswana BCL Limited operates the only Flash Smelting Furnace on the African continent, at Selebi-Phikwe, situated in north-eastern Botswana. The furnace was commissioned in 1973 and produces a high-grade sulphide matte containing nickel, copper and cobalt, which is shipped to refineries in Zimbabwe and Norway for further processing. This paper outlines the recent process improvements and plant expansions that have resulted in a capacity increase from 40 000 to 60 000 tons per annum of metal production.

Jan 1, 2006

By Taylor G. H

The Triassic Ipswich (SE. Queensland) coals are of bituminous rank. The more exact rank of individual samples was determined by measuring the reflectance of the vitrinite. While in general the rank of the coals increases with stratigraphic depth, minor reversals, probably related to igneous intrusions, occur.The Ipswich coals form a coherent group so far as petrographic type is concerned. All are comparatively rich in vitrite and clarite, cutinite being the common maceral of the exinite group. The mineral contents of all the coals are comparatively high, clay and quartz being most abundant. The coals appear to be of essentially autochthonous origin, and to have been formed under conditions of fairly rapid subsidence.While the use of the coals is at present restricted to combustion, most have pronounced coking properties, as would be predicted from their petrographic composition and reflectance. However, the high mineral content of the coals would be a limiting factor in their use for coke-making.INTRODUCTIONDuring the last ten years, the Division of Coal Research, Commonwealth Scientific and Industrial Research Organization has carried out an extensive investigation of Australian coals, providing a wide range of analyses of most of the important of them. Special attention has been given in recent years to Queensland coals.Most seams were sampled as a number of subsections, enabling the internal variations, as well as the overall properties, to be assessed. The lenticularity of many of the mineralrich layers may tend to limit the significance of the samples, particularly in respect of ash yield, but although the vertical distribution of mineral matter may vary considerably from one sampling position to another, the lateral variation of the total mineral matter in the whole seam may not be great.Apart from extensive chemical analyses and utilization...

Jan 1, 1963

The schlieren technique describes an optical analysis method designed to enhance light distortions caused by air movement. The ability to visualize air flow has significant implications for analyzing underground mine ventilation systems, including the enhancement of surveys and models. Currently, traditional schlieren methods are impractical underground. Background oriented schlieren (BOS) provides a solution to this problem. BOS requires two primary components, a professional quality digital camera and a schlieren background. A schlieren background is composed of a varying contrast repetitive pattern, such as black and white stripes. This background allows the camera?s sensor to capture minor light diffractions, such as those caused by air flow. Although BOS shows great potential for ventilation analysis, sensitivity is an issue. This paper seeks to validate the BOS technique for imaging flow through a regulator by comparing BOS images with traditional schlieren images. This paper also outlines initial experimental efforts used for the validation.

Jan 1, 2011

By Lifeng Zhang

The transport of fluid, heat ,and particles (bubbles and solid inclusions) in flowing molten steel is investigated in steel refining ladles, the continuous casting tundish, continuous casting mold and strand, and steel ingot casting processes. The two-equation k-?? model is used to simulate the turbulence. Multiphase fluid flow is numerically simulated with a Lagrangian-Eulerian approach, an Eularian-Eulerian approach and the Volume Of Fluid (VOF) method. The simulation can predict inclusion trajectories, inclusion removal fraction, free surface waves and other phenomena, which can be used to optimize these important metallurgical operations.

Jan 1, 2006

The Mount Angelo prospect outcrops as two copper rich gossans, the larger of which is 250 ft long and 70 ftwide. The mineralization is epigenetic and replaces part of a brecciated and disturbed lime tone and calcareou sediment sequence.Magnetic and self potential survey indicated a substantial body of sulphide mineralization, the top of which was approximately 100 ft below the surface.Diamond drilling confirmed this and established the presence of a mineral body of at least 500,000 tons, extending to a depth of 300 ft. Of the 500,000 tons, 200,000 ton are primary copper ore which a ays 2 per cent copper.This mineral body is not economic at present, but could become economic if copper mining is established elsewhere in the district...

Jan 1, 1966

By J. F. Archibald

A research effort has been undertaken, under Workplace Safety and Insurance Board of Ontario (WSIB) sponsorship, to characterize the support capabilities of conventional and innovative spray-on lining materials for mitigating dynamic failure effects created by simulated rockbursts. Conventional spray support media, such as shotcrete and fibrecrete linings, and a variety of new spray-on lining materials [thin, spray-on liners (TSLs)], typically polymer-type thin coatings, were subjected to simulated rockburst influence. For baseline comparison, conventional rockbolt and bolt-and-mesh support products were also evaluated. Observation of lining performance was undertaken through completion of field-scale support and rock detonation trials. Controlled blasting tests were conducted at the Queen’s University Explosives Laboratory to examine the effectiveness of the variety of surface coating agents for modifying dynamic rock spalling processes. All tests were performed upon largely undisturbed and homogeneous rock materials in highly repeatable fashion. All blasts were observed seismically and photographically to provide detailed information concerning rock motion, surface fracturing, ejected fragment motion and support liner survivability characteristics. These material comparison trials were performed to assess the relative effectiveness of a wide range of currently available area support techniques for suppressing hazards associated with dynamic rock ejection. The results of this study validate that thin, spray-on linings may be equally as effective, and often better, than conventional support materials at mitigating rockburst or like damage in highly stressed mine environments.

Jan 1, 2004

By Alun J. Davies

This paper describes a design-build project for the construction of a tanker wharf for 150,000 dwt vessels. The tankers deliver oil from offshore oil fields to a Transshipment terminal on the south coast of Newfoundland. The project described is an expansion to a previously constructed facility, adding an additional berth. The first berth was designed conventionally as concrete structures supported on groups of independent, single piles. The second berth was awarded to Peter Kiewit Sons' Co. Ltd. based on an alternate design which utilized a "jacket" concept whereby prefabricated steel frames are placed on the seabed and serve as permanent templates and also give lateral support to the piles, thereby increasing their load capacity. This led to economies and time savings. Discussed herein is the design process and the field installation, covering the jackets, driven pipe piles, and the rock anchors.

Jan 1, 2000

By Parker JB

The Channar Iron Ore Mining Project (the Project) is a joint venture involving the Hamersley Holdings group (Hamersley) and the China Metallurgical Import and Export Corporation (CMIEC). The Project represents the first new iron ore mine development in Australia since 1971/72 and is the first major overseas mining investment by the People's Republic of China (PRC). The Channar mine is being constructed in the Pilbara region of Western Australia and will operate for more than 20 years supplying the PRC with 200 M tonne of high grade iron ore. The Project is configured to take advantage of Hamersley's existing production and support facilities. The Joint Venturers will invest A$280 million to achieve an initial production rate of 3 M tonne/yr and an additional A$120 million over the next 8 years to achieve full capacity of 10 M tonne/yr. Financing the Project to meet the requirements of both Hamersley and CMIEC, with the dependance of the Project on Hamersley's infrastructure, and in a depressed iron ore market, required an innovative financial structure to be arranged in a limited period. This paper describes both the financial structure and its implementation, and draws a number of conclusions regarding the financing of resource projects.

Jan 1, 1989

By A Jäger, J L. Lett, J Rachocki and B Mobilio

The Newcrest Mining Limited Cadia East Panel Cave mines near Orange, New South Wales, Australia commenced production 1200 m below the surface in May 2014. Understanding the mine-wide impact caving had on excavation stability was a primary objective to ensure a safe working environment as production ramped up in the Panel Cave 1 operation and establishment activities were implemented in Panel Cave 2. The impact of cave interaction between Panel Cave 1 and Panel Cave 2 and establishing monitoring systems to assist mine planning and production as both caves joined is explained in this paper. Monitoring tools such as a microseismic system, open holes, HI-cells, extensometers, fibre optic sensing, cave markers, closure monitoring, underground observations and damage mapping were used to characterise the performance and position of the cave back. The data and observations collected were compared to predictions from numerical and empirical methods and used to calibrate the numerical models for forward prediction and to develop site empirical design tools. The results and methodology for monitoring deep high-output caves are the key discussion points in this paper.CITATION:Lett, J L, Jäger, A, Thornhill, T, Rachocki, J and Mobilio, B, 2016. Geotechnical challenges in cave monitoring – a modern approach, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 203–216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

THE furnace described in this paper was installed and has been used by the writer for the melting of rich gold-bearing material, and has given complete satisfaction. It may, therefore, prove of interest to other metallurgists who are faced with a similarproblem. A furnace of this type should be most suitable for the reduction of "cyanide preeipitate," "charcoal ash," "anode sludge," &c. formerly the melting was done in fire-clay crucibles, using coke or crude oil as fuel, but this method is costly, slow, and unsatisfactory. A small water-jacketed blastfurnace was also tried on this material after briquetting it, but was discarded in favour of the electric furnace. The furnace may be described as a simple form of the Heroult resistance furnace, with an adjustable upper electrode and a fixed bottom electrode. This is in accordanee with Stansfield's classification of electric furnaces. The heating is mostly due to the resistance offered the current by the molten slag. The melting chamber consists of a steel drum 14 in. in diameter and 21 in. high, and is lined with silica bricks specially made to fit the shell. The internal diameter is G in. The bricks contain 92 % silica, are made from calcined quartzite bonded with fireclay, and are similar in composition to those used for lining steel converters. They are set in a mixture of finely-ground quartzite and clay, and well dried out. The shell is bolted to a steel plate, which forms the decking of a truck running on rails, so that the furnace can be moved under ahood for carrying off the fumes. A cast-iron slag spout is bolted to the shell below the tapping hole, which is 4 in. from the bottom of the shell. Opposite this another hole 1 in. in diameter is drilled through the shell and lining for the passage of the lower...

Jan 1, 1918

By J. Hartikainen

19 papers were allocated to this session by the paper classification committee, 8 related to bored piles, 5 to continuous flight auger piles (CFA piles), 3 to slurry trenches, 2 to both bored piles and slurry trenches, one of them also dealing with root piles. There were no papers dealing with root piles only, as root filling is a different technique. One paper concerns sheet piling (Table 1). Table 1. Papers for session 1: Recent Technological Developments in Deep Foundations with Soil Excavation. [ ] Table 2. Classification of pile type in Belgium - van Impe W.F. /10/. [ ] Trends in piling Trends in piling in Central Europe were studied by van Impe for his brilliant lecture to the Finnish Civil Engineering Society. He claimed that bored piling is on the decrease and CFA pilling on the increase (Table 2). Thus the numbers of papers presented here do not conform to recent developments or trends. The papers submitted arc of course influenced largely by the fact, observable in Table 3, that bored piling is

Jan 1, 1994

By S. Kelebek, C. Gibson, M. Aghamirian

"Global niobium production is currently dominated by three operating mines, Araxá and Catalão in Brazil, and Niobec in Canada. Although over 90% of the world’s niobium is mined and processed in Brazil, a number of high grade niobium deposits exist worldwide. The advancement of these deposits depends largely on the development of operable beneficiation flowsheets. Pyrochlore, the primary niobium bearing mineral, is typically upgraded by flotation with amine collectors at acidic pH, and often includes a reverse gangue flotation stage prior to pyrochlore flotation. Challenges related to the flotation of niobium ores include complicated flowsheets which require pulp pH adjustment from alkaline to highly acidic conditions, difficulty recovering fine grained pyrochlore, producing concentrates that meet specifications, and minimizing the losses to reverse pre-flotation gangue concentrates, slimes, and tailings. The specific flotation challenges associated with different niobium ores are discussed. In some cases, the use of alternate flotation reagents and flowsheets are required to achieve reasonable gangue rejection and maximize recovery, particularly of very fine pyrochlore grains.INTRODUCTIONNiobium is a transition metal primarily found in the oxide minerals pyrochlore (Ca,Na)2Nb2O6(OH,F) and columbite (Fe,Mn)Nb2O6. After physical upgrading, pyrochlore is converted into a ferroniobium product which is largely used in the production of high strength low-alloy steel. Today’s niobium market is dominated by the Companhia Brasileira de Metalurgia e Mineração, whose Araxá operation produces over 80% of the world’s niobium. There are two smaller operations, Niobec in Canada, and Catalão in Brazil, which account for the remaining production (U.S. Geological Survey, 2013).A number of niobium deposits exist globally, their advancement dependent on the development of operable beneficiation flowsheets. Pyrochlore, the predominant niobium bearing mineral, is commonly upgraded by flotation with cationic amine collectors in acidic pulp conditions. However, many niobium ores do not respond to this typical flowsheet because they are either highly refractory or niobium deports to other minerals such as columbite, ilmenite and rutile, which are not as responsive to this reagent scheme (Bulatovic, 2010). Other reagents, such as alkyl hydroxamic acid, have been studied extensively and while promising, are not without their own inherent issues including lack of selectivity over iron oxide minerals, and high addition rates (Ni & Liu, 2012; Gorlovskii, Eropkiny, Koval, Strelstin, Khobotova, & Shtchukina, 1968; Gorlovskii, Khobatova, & Shtchukina, 1966).It is the aim of this report to highlight the challenges associated with the physical upgrading of niobium minerals through examination of the flotation behavior of two different ore systems. In order to overcome these challenges it is important to thoroughly understand the limitations of typical flowsheets/reagent schemes currently employed in operation."

Jan 1, 2015

By P. N. Anyalebechi

The effects of solidification rate on the cast microstructures of aluminum alloys 6009 and 6016 have been investigated with directionally cooled laboratory-size ingots, at 0.2-10.1 K/s and 0.4- 23.1 K/s, respectively. These ranges of solidification rate are within those observed in commercial-size ingots. In both alloys, the average dendrite cell size and second phase particle size decreased with increase in average solidification rate and with a decrease in average local solidification time. However, at comparable solidification rates, the dendrite cells and second phase particles are finer in the shorter freezing range alloy 6009 than in the longer freezing range alloy 6016. This is provisionally attributed to the earlier formation of second phase intermetallics at higher temperatures during solidification and to the formation of greater amount of the relatively coarse plate-like ß -phase (Al9Fe2Si4) phases in alloy 6016. In general, in both alloys, the types and relative amounts of the second phase particles in both alloys are independent of solidification rate.

Jan 1, 2006

By Louis Huntoon

HISTORY of the Porcupine area has been pub-lished in detail by the Ontario Bureau. of Mines in several issues of its annual reports. An. interesting volume could be written on: this topic; especially if personalities were introduced, such as the. transaction whereby the original title to the Hollinger group of claims was settled between Ben Hollinger and Alex Gillies by the toss of a coin. The early history of the McIntyre mine also had its thrilling events, such as its manager, R. J. Ennis, dodging the sheriff and deposit-ing red-hot gold bricks in the bank to meet his pay-roll. The occurrence of quartz veins containing low gold values was reported in 1896 by E. M. Burwash and again in 1899 by W. A. Parks. The first application for a mining claim appears to have been applied for on Dec. 30, 1906, by W. 0. Taylor, of Toronto, one of the old employees of the Hudson Bay Co. On the recom-mendation of Mr. Taylor, early prospecting was done on the shores of Porcupine Lake. It. was not until the spectacular discovery of the surface croppings at the Dome mine, by J. S. Wilson in 1909, that a rush to the district took place. Exploration was carried on during 1910 and 1911. The big boom was on in 1911, when claims sold on the evidence of mere rock croppings, owing to the prevailing heavy overburden. Rock croppings with specks of gold brought big prices. The country was heavily timbered and most difficult to prospect. My first trip was made during the summer of 1911, while the railroad was under construction from Porquis Junction to South Porcupine. I published my observations in the Canadian Mining Journal, Dec. 15, 1911, discussing in particular the character of the ore deposits and the future prospects of the camp. The first mills were erected in 1911, only to be destroyed by the disastrous fire in July of that year. They were rebuilt and the first important shipments are recorded in 1912. The history of the camp from the discovery of the Dome to the present consists of alternate chapters of great optimism and those of a more non-committal nature. For the engineer unfamiliar with the character of the deposits of this area, and the north country in general, it is at times most difficult to draw conclusions and submit definite recommendations. When valuable orebodies apex at depth, with no surface showings other than slightly mineralized veins of quartz or quartz containing a little visible gold; when at depth valuable veins and ore deposits, paralleling the one being explored, are developed by cross-cutting, such as Nos. 85-58 on the Hollinger, which have been its largest producers, the engineer assumes responsibilities rarely called for in other mining districts. This fluctuating aspect is exemplified in the three large producers, and may be duplicated with some of the old producers now being explored.

Jan 8, 1923

The need for legislative reform of health and safety legislation has been recognised in New Zealand for about a decade. Previous legislation did not cover all work places, many areas were excluded from coverage, and there were at least 14 different acts and dozens of sets of regulations dealing with various aspects of health and safety.

Jan 1, 1993