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By P. J. Sylvester, D. H. C. Wilton, R. I. Wheeler, M. A. E. Huminicki, D. Evans-Lamswood

"Systematic characterization of the mineralogy of massive sulfide ore deposits can provide valuable insights into ore genesis and metallurgical processing that would not be apparent otherwise. We describe a method wherein (1) normative mineral abundances are calculated from whole-rock chemical assays using an algorithm, (2) the results are cast in block models, (3) the results are then verified with automated image analysis of a subset of samples prepared as grain mounts by backscattered electron imaging and X-ray mapping on a scanning electron microscope, and (4) those verified results are integrated with textural data determined by optical microscopy.The technique is applied to the magmatic Ni-Cu-Co sulfides of the Ovoid orebody, based on geochemical assays of 3175 whole-rock samples. Three principal ore zones are defined in the Ovoid. Type I ore occurs in the center of the deposit; it is magnetite-rich and pyrrhotite-poor with intermediate contents of pentlandite and chalcopyrite. Type II ore surrounds Type I ore and is pentlanditechalcopyrite- rich with intermediate contents of pyrrhotite and magnetite. Type III ore occurs at the base and along the outer periphery of the northern part of the orebody; it is pyrrhotite-rich and chalcopyrite- poor with an intermediate content of pentlandite, and a low-to-intermediate content of magnetite. La caractérisation systématique de la minéralogie des gîtes de sulfures massifs peut fournir des indications précieuses sur la genèse des minerais et le traitement métallurgique qui ne seraient pas disponibles par d’autres méthodes. Nous décrivons un procédé par lequel (1) un algorithme est utilisé pour calculer l’abondance de minéraux normatifs à partir d’analyses lithogéochimiques, (2) les résultats sont exprimés dans des blocs diagrammes, (3) les résultats sont par la suite validés par analyse d’image automatisée sur un microscope électronique à balayage en électrons rétrodiffusés et par cartographie en rayons X sur des échantillons constitués de grains montés en résine, et (4) les résultats de cette validation sont combinés aux données texturales obtenues par microscopie optique.Cette technique est appliquée aux sulfures magmatiques de Ni-Cu-Co du gisement Ovoïde, en utilisant les analyses géochimiques de 3175 échantillons de roche totale. L’Ovoïde comprend trois types de minerai. Le type I est situé au centre du gisement; il est riche en magnétite et pauvre en pyrrhotite avec des quantités intermédiaires de pentlandite et de chalcopyrite. Le minerai de type II entoure le minerai de type I et est riche en pentlandite et en chalcopyrite avec des quantités intermédiaires de pyrrhotite et de magnétite. Le minerai de type III se trouve à la base ainsi qu’à bordure externe de la partie nord du gisement; il est riche en pyrrhotite et pauvre en chalcopyrite, avec un contenu intermédiaire en pentlandite et une quantité faible à moyenne de magnétite."

Jan 1, 2012

By H. Clare Horwood

"In the Little Long Lac-Sturgeon River area of Thunder Bay district, Ontario, most of the known ore deposits occur in fractures, shear zones, and zones of brecciation, in folded sedimentary rocks . In two or three instances, however, deposits occur in Keewatin greenstones and in later granitic rocks of probable Algoman age.The principal regional features in the area are the long narrow bands of Keewatin volcanic rocks and Timiskaming sedimentary formations that extend east from lake Nipigon to Long Lac, a distance of about 65 miles. The belts continue to the east for many miles beyond Long Lac and probably for some distance to the west under the waters of lake Nipigon. They are intruded in places, particularly in the north, by large masses of diorite, granodiorite, and granite. Small intrusive masses of diorite and porphyry also occur in many localities throughout the area.The Little Long Lac-Sturgeon River mining area is the youngest camp in Ontario and has been in production only since 1934.The district is readily accessible from the branch line of the Canadian National railway between Longlac station on the main line and Port Arthur, and from the Trans-Canada highway No. 17. Both these means of communication traverse the area in a general east-west direction parallel with the principal structural trend of the rocks of the region.In the Little Long Lac section discoveries were made by W. W. Smith in 1931 (Hard Rock property) , by T. A. Johnson in 1932 ( Bankfield property) , by T. A. Johnson and T. Oklend in 1932 (Little Long Lac property) , by F. MacLeod and A. Cockshutt in 1933 (MacLeod-Cockshutt property) , and by George and Frank Papineau in 1935 (Hutchison Lake property).In the Sturgeon River section discoveries were made by Powers and Silam in 1925 (Northern Empire property), T. A. Johnson in 1931 (Dik-Dik property) , and by Russell and James Cryderman in 1935 and 1936 (Sand River and Leitch properties)."

Jan 1, 1954

By Y. Kusuda

Since 1981, the Annaka refinery has recovered zinc from zinc leach residues by the Waelz Process. The important considerations of this process are the prevention of the growth of coating accretions in the Waelz kiln and the improvement of the zinc volatilization rate. In this paper, simulation predictions and the results of the industrial operation regarding the prevention of coating accretions in the Waelz kiln and the improvement of the zinc volatilization rate at the Annaka refinery are reported and compared.

Jan 1, 2006

By Robert B. Parsons

"""I would be a rich man if I had a dime for every man hour spent by the bureaucracy on changing tax legislation."" Anonymous.The mind of a cynic might very well conjure thoughts about ""change for the sake of change"", given the protracted saga of federal sales tax reform in Canada. The latest chapter unfolded this summer when the Commodity Tax Review Group released its important report. Whatever sales tax changes, if any, are finally adopted will have profound effects on many aspects of doing business. The capital-intensive mining industry will not escape these effects.IntroductionThe Federal Sales Tax Review Committee, established by the Minister of Finance earlier this year, has published a report that is sharply critical of the government proposals to shift the incidence of federal sales tax from the manufacturer level to the whole sale level (sales to retailers). The Report recommends a continuance of the present manufacturer's tax, for the present, but with significant changes that would increase the tax cost on certain imports, smooth the administrative machinery and make appeals and determinations more open and equitable. For the longer term, the Report recommends a shift of the tax base to the retail level.Reform of the federal sales tax system has been under consideration for several decades. Briefly the history is as follows: 1940 Report of Rowell-Sirois Commission-proposed the eventual elimination of federal sales tax1956 Report of Federal Sales Tax Committee-proposed a shift in tax from manufacturer to wholesaler level1966 Report of Carter Commission-proposed shift to a retail tax1975 Discussion Paper on Federal Sales and Excise Taxation-concluded that retail tax conceptually best but provincial agreement/administrative problems present a major hurdle-proposed wholesale tax as best practical approach1977 Report of Commodity Tax Review Group"

Jan 1, 1983

By D. J. Farmer

Mining hoists are major components of any underground mine, however, the detailed design work required to get the actual power required for a particular hoist is outside the scope of preliminary feasibility studies. Nonetheless, a hoist is costly. Therefore, an accurate estimate is needed for the design parameters and the power required. There are two methods available, namely, the O’Hara method and the Society of Mining Engineers’ method. Tests were done for both methods employing nine friction hoists and 19 drum hoists currently in use at Canadian mines. The O’Hara method provided unacceptable results for both friction and drum hoists. While, the SME method was designed for American regulations and factors of safety which often differ significantly from Canadian ones, good results were obtained. The two relationships deter-mined were simply to add 5% to friction hoist design and to add 4% to drum hoist design. Modifying the SME method by these two factors will allow the hoisting system determined by the SME method to be within the error for a prefeasibility study.

Jan 1, 1997

By Douglas A. Sloan

"Recently, a number of major mining companies seemed unable to find a president from within the industry, and were searching outside the industry. From this, one could conclude that managers within the industry are either not being prepared or are not preparing themselves for presidential responsibility. Opinions were sought from a number of senior executives, to attempt to define the skills a prospective president should acquire and what actions a company could take or that a prospective president could take to acquire these skills.This paper contains summaries of the opinions obtained, along with the author's comments. The paper also describes the actions some companies are taking and the actions that an aspiring president can take to prepare himself for corporate management.IntroductionA manager is promoted up the management ladder when the manager's superiors believe that he is capable of handling a more senior position. Normally, the manager acquires this credibility by outstanding performance in his current management post, whether it be in a junior management (supervisory) or in a vice-presidential capacity.In most instances, the skills required for promotion can be acquired in the current position or, at worst, the abilities exhibited in a candidate's current role will convince his superiors that the necessary expertise for the more senior position can be acquired on-the-job. This is particularly the case when the new skills are felt to be an extrapolation of the old skills.However, in the case of appointment to presidential rank, there appears to be a need for new expertise which often is not acquired in normal management progression or, at least, boards of directors of some mining companies seem to believe this to be the case. The objective of this paper is to attempt to define the new skills that should be acquired by a manager who aspires to be the president, and to describe what actions might be taken by him to acquire them."

Jan 1, 1982

By E. V. Konopleva, H. J. McQueen

"The isothermal bainite transformation kinetics of low- and medium-carbon alloy steels after hot deformation and the rmocycling treatment (TC) has been studied by the magneto - metric method. Deformation was produced by rolling at 800°C-1000°C. TC included three cycles of rapid (30°C/s) electro-heating up to 900°C-1000°C followed by quenching.Hot deformation retards bainite transformation in the lower part of bainite range (<400°C) and accelerates it in the upper part (>400°C). The effect is greater for higher strain and lower deformation temperature. Deformation also diminishes the overall bainite fraction below 400°C and increases the completeness of reaction above 400°C.Thermocycling provides more uniform ultrafine austenite grains with average size of 3 µm -4 µm compared to 12 µm -14 µm after conventional heating. The transformation rate after TC was almost the same as after conventional heating in low-carbon steel but was faster in medium-carbon with no change in the completeness of reaction. The degree of acceleration increased with rise of transformation temperature.There are a number of factors which are responsible for a change in bainite transformation kinetics in austenite deformed at high temperatures or subjected to TC. One of the most important factors is the refinement of structure, another one is structural and chemical inhomogenity of austenite due to deformation or to rapid heating. To estimate the contribution of these factors, ?-transformation was studied after different austenitizing conditions (low-temperature heating at 850°C- 950°C; high-temperature heating at 1100°C; step treatment – austenitizing at 1100°C, then cooling to 950°C-850°C). The results obtained make it possible to conclude that the structural and chemical inhomogeneity of austenite activate the bainite reaction while the grain refinement retards it. Intensity of the effect produced by each factor depends strongly on the steel composition."

Jan 1, 1997

By V. Bonilla-Sierra, M. Elmouttie, L. Scholtès, F. V. Donzé

In the presence of joint sets sub-parallel to a slope face, the stability of the rock mass is controlled by the shear strength of the joints. On one hand, if the joints are persistent their shear strength can be assessed according to Mohr-Coulomb criterion, assuming appropriate values for the cohesion and the friction angle on the joint surface. On the other hand, if the joints are non-persistent with their continuity being interrupted by the presence of rock bridges, their shear strength will increase considerably. In this latter case, the contribution of the rock bridges to the shear strength of the joint has to be accounted for in order to better assess the stability of the rock mass. A numerical analysis of the progressive failure of a rock slope involving a non-persistent joint has been set up based upon simulations performed using a Discrete Element Method (DEM) algorithm specifically enhanced for the modeling of jointed rock masses. Pre-existing discontinuities are explicitly accounted for in the model by using a modified contact logic that ensures an explicit and constitutive mechanical behavior of the joint planes. In addition, rock bridges can be spatially distributed along these joint planes following a prescribed probabilistic technique. Jennings’ formulation (Jennings, 1970) is considered as one of the first rock slope analysis that evaluates the shear resistance to sliding as a weighted combination of the shear resistance of the intact rock and the joint planes. The validity of this formulation is discussed in the present study. Contrary to the Jennings’ formulation, we show that tensile failure is an important mechanism, particularly as the dip angle of the sliding plane increases.

Jan 1, 2015

By C. Dragusanu, J. Sims, J. Connolly

Based on a statistical analysis of the categorical and numerical data from the established geological model, a geochemical classification of mineralization has been shown to be objective in nature and correlated to the envisioned metal extraction process. Multivariate chemical classification has the potential to discriminate within a combined response from different types of alteration and metal abundances. Distinct domains of chemical response determined by clustering analysis were used as a validating criterion for a geologically driven metallurgical testing program. The groups established are spatially linked to the geological process responsible for their genesis, providing clarity in geometallurgical and resource modeling.

Jan 1, 2011

By M. Djivre, T. Eger, A. Godwin, I. Bhattacherya

Load-haul-dump vehicles (LHDs) are extensively used in underground mining, however, equipment design and operating conditions contribute to restricted operator sight lines. The inability to clearly see people, objects, or hazards around the machine has contributed to a number of accidents including fatal injuries. In order to identify vehicle design characteristics resulting in restricted and blocked sightlines, line-of-sight assessments are traditionally completed in the field. However, field methods are unable to evaluate lineof- sight under dynamic operating conditions, and are limited in their ability to provide feedback on the impact of various operator characteristics such as sitting height. Results of this research show computer simulation and virtual reality can be successfully used to evaluate line-of-sight during the operation of LHD vehicles. In order to benefit from virtual reality applications, the work environment, LHD vehicle, and human posture need to be represented as accurately as possible. A computer simulation program with ergonomic analysis features, Classic JACK 3.1, was successfully used. Threedimensional CAD models of LHDs were developed from manufacturer specifications and pictures taken from LHDs currently in use. The LHD models were imported into the JACK environment, a digital human was positioned in the cab of the LHD vehicle, and the vehicle and human were driven over a typical mine route. Real-time feedback in the JACK program was used to identify what the operator could see under different operating conditions. Machine characteristics and operating scenarios resulting in impaired line-of-sight were successfully identified with this method. The JACK program could also provide real-time feedback on the human’s joint forces and torques, strength requirements, postural comfort, and metabolic energy expenditure. As a result, this method could be used to successfully evaluate musculoskeletal injury risk factors along with system design recommendations to improve workplace safety and productivity in any setting. The LHDs evaluated in the JACK software package can also be combined with mine models and imported into other VR software packages (e.g. Blender) in order to enable viewing in Laurentian University’s Virtual Reality Laboratory. The VR models using these packages can be viewed in stereo to provide better appreciation of spatial vision issues.

Jan 1, 2005

By G. Lodewijks

This paper explores the savings that can be achieved in the energy consumption of belt conveyors used in mines by changing the conveyor components, the operational parameters of the system or the belt properties. First the concept of energy savings is introduced by looking at the energy consumption of belt conveyors from a theoretical point of view. Also methods for the calculation of the power consumption of a belt conveyor and the associated emissions are presented. Two case studies are presented in which the effects of the change of the operational parameters of the system, in this case the belt speed, and the belt properties, in this case the application of aramid products in the belt, are presented.

Aug 1, 2013

By Funsho K. Ojebuoboh

With several “green” applications on the horizon, bismuth has become an even more important minor metal in the smelting and refining of lead. Smelters with a complex sulphide feed invariably deal with bismuth. Its behavior during the smelting of lead in conventional sinter-blast furnace operation is discussed. Because it readily deports to the lead phase during the refining of lead, its separation from refined lead remained unsatisfactory in early lead production. When commercial requirements of bismuth in lead became more stringent early this century, the procedure where by calcium and magnesium is used todebismuthise lead was developed. The present conduct of this 1936 process, the Kroll-Betterton process, is discussed with emphasis on operational improvements.

Jan 1, 1996

By Baochun Wang, Hongli Jia, Zhaolian Wang, Fengliang Liu

"Promote and apply a new beneficiation technology and equipment effectively processing the refractory and medium-fine grained weak-magnetic minerals. HUATE® Forced-oil Cooling Vertical Ring WHIMS adopts the transformer oil cooling technology to cool excitation coils, solving the easily generated scaling problem resulting from water cooling, thereby to eliminate the demineralized water system. With <25 temperature ?raise, its magnetic field is stable. Wrapped by outer magnetic armor, it can generate a background intensity 1360kA/m. It effects very well in 1) wet preseparating the weak-magnetic coarse grains, like hematite, manganese ore, ilmenite, and purifying the concentrate; 2) removing the ferrous impurities and purifying the non-metallic minerals, like quartz, feldspar, kaolin; 3) enriching and recovering tailings from non-ferrous metals, like copper, lead, cobalt, molybdenum, thereby to greatly improve the mine resource utilization. It has applied 14 relative patents in China, and the invention patent in 56 countries, like Russia, USA, Australia, via PCT international organization. HUATE® WHIMS has been applied and accepted in more than 100 mines in and out of China. Compared with water cooling vertical ring WHIMS, it’s energy-saving and water-saving, and avoiding generating the scale. While compared with JONES WHIMS under the same separation indexes, it’s featured of more space-effective, lighter, lower costs, higher gradient, higher efficiency, larger processing capacity and wider grain application scope. Greatly promoting development of mineral processing technologies, HUATE® WHIMS is the equipment to reduce costs and improve efficiency urgently needed by the mine enterprises now.INTRODUCTIONAt present, influenced by the price and production factors, the international market demand for the grade of iron ores is increasing continuously. Restricted by the ore occurrence state, the beneficiation technology level and product economic value, every year the stope strips the stockpiling and discards hundreds of millions of tons of waste rocks containing iron, especially the weak magnetic hematite and limonite with <20% Fe%. The utilization technological bottleneck of these waste rocks makes their concentration ratio as high as 5-6, which leads to the huge wastes of energy, materials and beneficiation reagents and the increase of production costs. The effective solution is to improve the selected Fe% of the waste rocks like hematite. With the successful application of HPGR technologies in Chinese large iron mines, the mill feeding size has been reduced to 6-0 mm or 3-0 mm from the original 15-0 mm in the crushing system with 3 stages of crushing and 1 stage of closed circuit. This creates the conditions for the wet separation and recovery. While for the medium-fine grained weak-magnetic minerals, it lacks of the effective separation and recovery equipment in the world, which’s badly in need of R&D of the medium-fine grained high gradient wet strong magnetic preseparation equipment."

Jan 1, 2016

By Guadalupe Sanchez, Roel Cruz, Sergio Castro, Claudia Beltrán, Isabel Lázaro

The recovery of zinc in refineries is strongly affected by the formation of zinc ferrites during the roasting of zinc concentrates. To achieve the highest zinc recovery most of these plants operate under high acidity and high temperature conditions in their leaching circuits. However, under these conditions high iron dissolution occurs. For iron control the common practice is to precipitate it as jarosite, and calcine is normally used as neutralizing agent. This practice causes a significant loss of metal values associated with the calcine, such as zinc ferrites and silver insoluble phases. These metal values are carried by the jarosite into confined waste in many plants. In order to diminish such losses, it is necessary to use a neutralizing agent that could substitute the use of calcine. An alternative neutralizing could be the basic zinc sulfate (BZnS). This work presents the results of a laboratory analysis on the required conditions for the BZnS production from process streams of a zinc refinery plant. Neutralizing behavior of BZnS was evaluated in iron precipitation as jarosite, in order to establish the feasibility of replacing the calcine and decrease the loss of zinc and other metals values during the iron removing step of the hydrometallurgical circuit of the zinc refinery under study.

Jan 1, 2014

By J. M. Cooper

The HBMS reverb furnace in Flin Flon was originally designed in the late 1920s. Throughout the decades campaign life has been increased due to operational practices, technological changes and brick quality improvements. In recent decades the campaign life had been extended such that a complete rebuild was scheduled every 3 years. The latest furnace rebuild and start up has been after a campaign life of nearly 6 years. Brick construction methods and techniques along with furnace operational practices allow the present campaign to be double that of the historical campaign length.

Jan 1, 2007

The comminution circuit at Tarkwa Gold Mine was commissioned as a Single Stage SAG mill operated in closed circuit with hydrocyclones designed to process 4Mtpa. The circuit was later expanded by adding a secondary ball mill in closed circuit with hydrocyclones with a view to treat 12Mtpa. The change in the circuit configuration and assigning the low aspect ratio SAG mill for primary grinding application makes the Tarkwa experience unique in terms the optimisation strategy and operating philosophy. This paper reports the findings from a series of surveys performed on this plant. The surveys reported include data obtained when the SAG mill was operated as a single stage mill in closed circuit with hydrocyclones and also SABC mode under two different feed conditions. The differences in operating philosophy between the initial single stage SAG circuit and the current SAG/Ball mill circuit are discussed.

Jan 1, 2012

By K. Hanumantha Rao, A. Javadi

Our recent studies revealed that the sulfide minerals in contact with water during grinding produced hydrogen peroxide (H2O2) where the amount of H2O2 production by the minerals found to be in the order of pyrite > chalcopyrite > sphalerite > galena. The H2O2 effect on the oxidation of pulp components and its influence on the concentrate grade and recovery in flotation have been studied and the results have been presented and discussed in this paper. Studies have also been carried out to build correlation between percentage of pyrite in the concentrate, grinding conditions and concentration of OH•/H2O2 in the pulp and as well of controlling the formation of these species through known chemical means for depressing the generation of the oxidant. Flotation tests using a complex sulfide ore with the same reagent scheme that is being used at Boliden concentrator in Sweden but with the addition of i) collector and depressant, ii) Na2S reductant and iii) inorganic (EDTA) and organic (TETA) surface modifiers, during grinding stage have been performed to judge the beneficial or detrimental role of H2O2 on the selective flotation of sulfides. The results demonstrate that the selectivity of metal sulfides against pyrite increases with increasing generation of H2O2 in the pulp liquid. H2O2 is also found to be a better oxidant in chalcopyrite-galena flotation separation than the commonly used K2Cr2O7.

Jan 1, 2016

By S. K. Kawatra, S. J. Ripke, T. C. Eisele

It was determined by the authors that the water that remains in the filter cake after filtration in iron ore concentrators can contain several hundred times greater concentrations of calcium ions and other cations, due to surface chemical effects carrying the ions along with the water. Filter cake from two plants was analyzed. The water retained in samples of magnetite concentrate filter cake in Plant 1 contained 5088 ppm calcium and 5995 ppm magnesium, while the Plant 2 filter cake contained 231 ppm calcium and 119 ppm magnesium. These levels were dramatically elevated compared to the water that was removed from the concentrate by filtration for recycle to the plants (9 ppm calcium/15 ppm magnesium for Plant 1, and 11.9 ppm calcium/9.3 ppm magnesium in Plant 2). In addition to possible effects on agglomeration performance, the presence of these cations also affected the efficiency of filtration. In order to reduce the effects of these cations on filtration in Plant 2, carbon dioxide was injected into the slurry before it entered the filter press. This was found to increase filtration rates by up to 23.7%. Comparison of the results from the two plants shows that the concentrations of cations present in the filter cake will vary greatly from plant to plant, with correspondingly large variations in their effects on plant operations.

Jan 1, 2004

By M. Uszko

The paper presents the conditions for determining the selection of methods for methane drainage in Polish hard coal mines. Various factors for the evaluation of methane drainage performance are used, including the methane drainage effectiveness ratio. However, as will be discussed there are limitations to the methane drainage ratio approach resulting from the characteristics of the deposits extracted in Kompania Weglowa S.A. coal mines.

Aug 1, 2013

By H. R. Bullis

"A 2003 paper discussed the idea that as gold mining companies grow larger it becomes more difficult for them to discover or acquire new gold deposits large enough to replace extracted reserves on an annual basis. Deposits of the size required to replace annual production of very large gold producers (VLGPs) are statistically few. An update in 2005 reviewed VLGPs with respect to production, reserves, and reserve life and observed recent changes in the gold mining industry. Now, more than 12 years later, this paper explores how those VLGPs have fared and how the gold mining industry has changed. KEYWORDS Gold, Gold price, Production, Reserves, Very large gold producer (VLGP) RÉSUMÉ Un article de 2003 examinait le concept selon lequel, à mesure que les sociétés d’exploitation aurifère se développent, il leur devient de plus en plus difficile de découvrir ou d’acquérir de nouveaux gisements aurifères suffisamment grands pour remplacer les réserves qu’elles extraient annuellement. Statistiquement, il existe très peu de gisements de la taille requise pour remplacer la production annuelle des très gros producteurs d’or. Une mise à jour de l’article en 2005 se penchait sur la production, les réserves et la durée de vie des réserves des très gros producteurs d’or ; elle portait sur les récents chan¬gements au sein de l’industrie de l’exploitation aurifère. Aujourd’hui, plus de 12 années plus tard, cet article explore l’évolution et les résultats de ces très gros producteurs d’or, ainsi que les changements qu’a connu l’industrie de l’exploitation aurifère. MOTS CLÉS or, prix de l’or, production, réserves, très gros producteurs d’orINTRODUCTION In 2005, the world’s top five gold producing companies were Barrick (after purchasing Placer Dome; 9.1 million ounces; Barrick Gold Corporation, 2005; Placer Dome, 2005), Newmont (8.2 million ounces; Newmont Mining Corporation, 2005), AngloGold Ashanti (6.2 million ounces; AngloGold Ashanti Limited, 2005), Gold Fields (4.2 million ounces; Gold Fields Limited, 2005), and Harmony Gold (3.0 million ounces; Harmony Gold Mining Company Limited, 2005). During the years leading up to that point, there had been a flurry of activity in the gold sector directed at consolidating production and reserves to create very large gold producers (VLGPs). As defined in Bullis (2005), a VLGP is a mining company whose primary busi¬ness is gold production and that has annual gold production more than 5 million ounces. A stated corporate goal of several of the VLGPs at the time was to become the largest gold producing company in the world."

Jan 1, 2019