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By E. L. Bruce

EUROPEAN Russia is mainly a great plain, the average elevation of which is only 600 feet above sea level and the maximum elevation less than 1,200 feet (Figure 1). The main divide between the Arctic ocean and the Black sea and Caspian sea is an indistinguishable topographic feature from which the Dneiper and Don rivers flow southward to the Black sea and the Volga river to the Caspian. The valleys of these rivers are but little below the general level (Figure 2). To the south, this great, rolling plain is broken by a low ridge of Precambrian gneisses and intrusive rocks. The Crimea is an upland from which the descent to the Black Sea coast is precipitous (Figure 3). The Ukrainian Soviet Socialist Republic occupies the southern part of the plain. It is the southwestern unit of the Union, bordered by Rumania and Poland on the west and by the Crimean Soviet Socialist Republic on the south.

Jan 1, 1938

By G. O. Oniyide, H. Yilmaz.

"This paper presents the result of the research done on the effect of temperature on the dilatancy of rocks from the Bushveld Igneous Complex (BIC), where the South African Platinum mines are located. The BIC has higher virgin rock temperature (VRT) than the gold mines of the ‘Witwatersrand Basin Complex’. If the platinum mines advance to ultra-deep levels as the gold mines, since the Merensky Reef has been reported to extend beyond 5km, then the virgin rock temperature at 5 km below surface would be approximately 140oC. Hence, there is a need for the investigation of rock behaviour at high temperatures. Five different rock types (norite, leuconorite, mottled anorthosite, pyroxenite and chromitite) were tested in a 2600 kN servo-controlled multi-purpose triaxial testing machine. The tests were done at a constant strain rate of 5 x 10-1 S-1 and a confining pressure of 10 MPa within temperature range of 20 °C (ambient temperature) to 140 °C. The results show a general strength reduction and increasing dilation angles with increasing temperatures. The results also demonstrate that dilation angle is close to the internal friction angle at lower temperatures; however, they are greater at higher temperatures.INTRODUCTIONMany challenges are faced with increasing depth of mining in underground mines. The most obvious are heat, in-situ stresses and those associated with logistics. Issues related to underground heat have mainly focused on the side effect of heat on workers' health, increasing production costs as a result of higher cost of ventilation. The effect of increasing temperature with increasing depth on the behavior of rock has not been given much consideration. Generally, gold mines in South Africa are deeper than the platinum mines but the latter have higher temperature gradient, which makes the platinum mines to be warmer at similar mining depths. Although the study of the effect temperature on the behaviour of rock can be beneficial to both gold and platinum mines, the focus of the research is limited to the platinum mines because of their higher temperature gradient. Donoghue (2004) stated that the virgin rock temperatures (VRT) and air temperatures increase with depth, due to the geothermal gradient and auto-compression, that is, compression of air by its own weight."

Jan 1, 2015

By A. Alfantazi, E. Asselin

"The corrosion of commercially pure titanium (CP-Ti) was studied from room temperature up to medium temperature (~160°C) under conditions relevant to medium temperature chalcopyrite leaching processes. The corrosion rates were measured by immersion and electrochemical tests in sulfuric acid. The influences of chloride, cupric and ferric ions on the corrosion rate and behavior were also investigated. Corrosion of the CP-Ti did not account for the total current density measured by linear polarization tests. The corrosion rates of CP-Ti under medium temperature leaching conditions were surprisingly high. The corrosion rate measured in ferric containing solution at 160°C was approximately 20 mm/yr.INTRODUCTIONTitanium exhibits excellent corrosion resistance in many aggressive environments because of the formation of a very chemically stable, highly adherent, and protective oxide film on its surface (Mitsuo et al., 2002). Because titanium is the only metal available at a reasonable cost that resists the high temperature corrosive slurries in many leaching processes, it is often chosen as autoclave liner material where it is subjected to severe conditions of acidity, temperature and pressure (Grauman and Say, 2000).A number of distinctly different hydrometallurgical processes for the pressure leaching of chalcopyrite have been developed and patented by various companies and they can be classified into low, medium and high temperature regimes (McDonald and Muir, 2007). For example, chalcopyrite concentrate may be processed at medium temperatures (115-175°C) and pressures of 800-2200 kPa (Dreisinger, D., 2006; Sahu and Asselin, 2011). The lixiviant may contain 20 to 55 g/L sulfuric acid, 8 to 12 g/L chloride ions, 10-25 g/L Cu2+ (Jones, 1995, 1997, 1999), and less than 1 g/L Fe3+ (Defreyne et al., 2005). The amount of these additions is determined by the grade of the ores and details are shown in Table 1."

Jan 1, 2012

By Norma G. González

La littérature et notre expérience en Bolivie dans une communauté minière très divisée comme celle de Huanuni nous montrent le besoin d?envisager des négociations gagnant-gagnant entre communauté et entreprise minière, non pas comme un point de départ, mais comme un résultat à atteindre, qui nécessite la préparation de conditions préalables. Cela implique fondamentalement de mettre l?accent sur le processus qui permettrait par la suite aux parties de mieux traiter les questions de contenu. Suivant cette hypothèse générale, l?initiative conjointe entre le Ministère des ressources naturelles du Québec et le CECI ?Développement des mécanismes de négociation entre communauté et entreprise minière? peut dégager, après un an et demi d?expérience pilote dans le site minier de Huanuni, département d?Oruro, Bolivie, les leçons préliminaires suivantes. Ce processus requiert: ??Agir, en tant qu?organisme consultant tierce partie, selon des principes et une méthodologie qui relèvent de la Communication publique et de la Médiation ; ??Comprendre et agir à partir de la ?réalité sociale? des parties en présence: l?entreprise minière, l?État et les différents groupes de la communauté; ??Intervenir sur les ?réalités sociales? des parties, par des actions d?éducation et de diffusion dans le but de préparer les personnes, les institutions et les organisations de la société civile, à des changements durables du modèle de communications existante; Approfondir la compréhension de la ?réalité sociale? du conflit (la culture du conflit, les méthodes populaires de résolution des problèmes et de gestion des conflits) afin d?offrire aux bénéficiaires les technologies appropriées pour la transformation de cette culture de confrontation violente en gestion constructive des conflits. Par ricochet, nous espérons ainsi faciliter l?attraction des investissements dans le secteur minier.

May 1, 2001

By L. E. Djingheuzian

"ForewordTHE FOLLOWING excerpt is taken from Fine Grinding Investigations at Lake Shore Mines (C.I.M., Trans., Vol. XLIII, 1940, p. 307):""MacCalman, who has carried out exhaustive testing on the accuracy of screen analysis, makes the following statement in his report, The Accuracy of Sieving Tests, Industrial Chemistry (London, England), Vol. XIV, p. 231:"" 'It will be shown that, as no specific relationship between the sieving value and the various dimensional features of the sieve is evident, though there is an apparent tendency for the sieving value to follow the average aperture size, it is apparently impossible to define the sieving value of a screen from dimensions alone, and the calibration of sieves for important tests on a specific material, whereby the sieving values of these sieves are related to that of an arbitrarily chosen master sieve by correction values, will be recommended."" 'It will be emphasized that these correction values are probably not applicable to other materials, or the same material of different size composition. Sieve users, for important tests or in cases of dispute, will be recommended to calibrate their sieves against a mutually acceptable standard with specified conditions of test, and to recalibrate at intervals' ""."

Jan 1, 1953

By K. Webb

At both the international and country level, the issue of how the mining sector and indigenous populations should engage on issues of mutual interest or concern has emerged as one of central importance and controversy; involving the mining industry, Aboriginal communities, governments, the courts, and other stakeholders. At its heart, stakeholder engagement is an ethical issue, although it manifests itself in international instruments, domestic laws, industry guidance and agreements. At the international level, the concept of ?free, prior and informed consent? (FPIC), while not subject to widespread agreement on the finer details of evolving definitions, seems to be emerging as an increasingly recognized engagement norm. Within Canada, through a series of decisions, the Supreme Court of Canada (SCC) has articulated a fiduciary obligation of the Crown to consult with and accommodate impacted Aboriginal groups on resource management issues. Provincial governments have been variously attempting to adjust their resource management regimes to stay in alignment with SCC and lower court decisions. Mining sector organizations, working with First Nations partners, have developed agreements to work together for mutual benefit. At the individual mine and community level, there have been instances of constructive engagement, as well situations of physical resistance and legal challenges. The purpose of this paper is to examine the potential impact of new rules under the Ontario Mining Act introduced in 2012 and taking full effect in 2013, which amongst other procedural specifications, addresses the issue of mining industry-Aboriginal consultation in exploration and development activities. Leading up to the passage of the regulations, representatives from some junior mineral exploration companies have been highly critical of the new rules. Similarly, there have been a range of responses to the new rules from some in the First Nations community. The paper will review the regulation in terms of its apparent alignment with SCC decisions and the international norm, compare the regulations with existing mining sector organization guidance documents, and it will draw on the stated perspectives and commentaries of First Nations communities, mining firms, governments, nongovernmental organizations, and others. Building on the foregoing, the paper will provide a preliminary analysis of the perspectives and potential impacts of the new regulation on various stakeholders, and on that basis, possible avenues for further consideration will be suggested.

Aug 1, 2013

By Jean-Yve Tremblay, Michel Prud'homme

"IntroductionIndustrial minerals include a group of more than fifty minerals which are marketed into almost all the sectors of industry; they are the backbone of many manufacturing industries. Table I shows major end-uses for industrial minerals in manufacturing sectors.At Energy, Mines and Resources, industrial minerals are divided in three major categories: (I) agro chemicals and chemicals, (2) construction mineral s, and (3) ceramics and specialty minerals. A listing of the major groups of minerals is shown in Table 2.Agro-chemicals and chemicals are sold on the basis of their chemical content and purity. Construction minerals or structural minerals are distinguished by their performance as low cost and bulky commodities. Ceramics and specialty minerals are performance-specific and are sold for their property on imparting functions on end-products. Industrial minerals have unique characteristics that are useful in many stages of processing; from crushed size to micronized fillers a single mineral ca n serve a broad range of industries because of its intrinsic properties.The Industrial Minerals Industry in CanadaCanada has a large industrial minerals base and is a world leader in the production of some of them. The total value of product ion of these minerals has grown by 115% over the last 10 years despite the misfortune of asbestos.Industrial minerals have shown remarkable growth in the past 20 years at an average annual rate of 9.2%, compared to 7.8% for metallic minerals. In 1986, the value of industrial minerals rose to $4.9 billion, or 14% share of the Canadian mineral production. Figure I shows the value of production of the mineral industry for the period 1966-1986.The leading segment in industrial minerals segment since 1976 is the chemicals and agro-chemicals sector which has an average annual growth rate of 5.75 % in terms of value of production. During the same period, the growth rate for the whole Canadian mining industry was 1.37% per annum. The chemicals and agro-chemical s sector increased its contribution to the total value of production of 2% to 6070 despite the growing share of fuel minerals with 59%."

Jan 1, 1988

By Dharmendr Kumar, Pradip, Beena Rai, Venugopal Tammishetti

"Due to rapid depletion of high grade Indian iron ores, there is a need to utilize low grade fines and slimes. However, these fines and slimes, in their current form, cannot be utilized in steel making due to their high alumina (6-10%) contents. Several beneficiation strategies such as gravity separation, magnetic separation, flotation and selective flocculation are currently being explored for the upgradation of low grade fines and slimes. In our previous work density functional theory simulations were employed to come up with selective flocculants for beneficiation of iron ore slimes. Our simulation results suggested that starch and guar gum are more selective towards iron minerals than other minerals present in the sample. Grinding of iron ore fines becomes necessary in some cases to achieve adequate liberation for removing alumina impurities in Indian iron ores. We have thus investigated effect of grinding of iron ore fines on its selective flocculation-separation.In the present work, we have taken natural iron ore fines from one of the Indian iron ore mines and ground it to -400 mesh (<37 microns) in dry and wet conditions. X-ray diffraction study confirmed the presence of minerals hematite, goethite, gibbsite and kaolinite in the sample. The fine ground samples were used in selective dispersion-flocculation study with corn starch and guar gum flocculants. It is interesting to note that even though the dry and wet ground samples possess almost similar particle size distributions, significant differences were observed in yield and grades of the concentrates thus produced. These differences may be arising due to the coating of alumina containing minerals on iron minerals. We have also studied the effect of addition of dispersant while grinding. Our study suggests that grinding conditions determine the efficiency of the separation process."

Jan 1, 2016

By D. W. I. Griffiths, J. C. Bélanger

"La Division Matagami de Minéraux Noranda inc. a profité de la construction de sa nouvelle mine (Isle-Dieu) pour continuer sa modernisation.L&apos;utilisation d&apos;automates programmables (PLC) s&apos;est intensifiée pour contrôler et automatiser de plus en plus d&apos;équipement dans ses minessouterraines, au concentrateur, dans les atelierset bureaux.Tous les PLC comrnuniquent entre eux et les IBM PC sont utilisespour exterioriser l&apos;information et faire Ie lien entre Ie personnel et les automates. Le système Central IBM 36 emmagasine les donnees traitees par lesPLC (a travers les PC). Ces donnees sont transmisesau programme d&apos;entretien de chaque equipement et compile les heures, cycles, tonnes, etc., fait imprimer automatiquement les feuilles d&apos;entretien préventif &apos;, etc.Les principales realisations adate et en progrès pour la mine Isle-Dieu sont:• automation complète du système de remblayage du concentrateur ala mine Isle-Dieu situee a2 km de la mine principale;• automation du fonctionnnement des ventilateurs qui comprendra la position des portes de ventilation, Ie chauffage, Ie débit, etc.;• automation des pompes, surveillance des sous stat ions électriques, concentration des gas (CO, SO2) à chaque niveau en tout temps et du propane à l&apos;entree d&apos;air frais;• tonnage et cycles par Ie treuil; et• contrôle d&apos;autres équipernents à differénts niveaux. D&apos;autres travaux furent egalement effectues par les employes, tels que:• la conversion d&apos;un Scooptram ST5A de diesel à électrique;• I&apos;installation complete de systèmes de depoussierage a I&apos;eau (scrubber) pour le concassage secondaire;• I&apos;installation d&apos;un marteau hydraulique avant les concasseurs coniques;• la rénovation des cellules de flottation ; et• l&apos;installation d&apos;un système de gardiennage par caméra. D&apos;autres projets seront effectués ou étudiés:• automation d&apos;un Scooptram"";• automation d&apos;un marteau hydraulique;• récupération de Scooptrarn; téléguidé:• gestion de l&apos;énergie, contrôle de la demande, surveillance et contrôle de l&apos;équipernent de machines fixes(compresseurs, boulloires, pompes à vide, génératrices, débits et pression d&apos;air, eau pour diagnostiquer les problémes, analyser les coûts;• concasseur portatif pour fabriquer de la pierre concassée pour utiliser dans les chemins sous-terre, et• utilisation de micro-ondes pour transmettre les images captées par camera."

Jan 1, 1990

By F. W. Gray

Foreword: It is not my purpose, in this address, to write the history of the Geological Survey of Canada, which has from time to time been reviewed by the officers of the Survey itself, and by men more competent than myself to handle so large a subject, but rather to set out some of the reasons for the regard in which the Survey is held by our Institute, the body best qualified to speak for the mining men of Canada. And, a further purpose is to publish the desire of our Institute that the work of the Survey shall be maintained at the highest pitch of efficiency the resources of our country. will permit, because to scrimp expenses on the Survey is &apos;to save at the spigot and lose at the bunghole." A historical examination of the grounds on which it may be asserted the Geological Survey has been, and still is, of fundamental economic value to our country, discloses a prescience on the part of the forefathers of Canada, calling for our admiring gratitude, and reveals a unanimity among the real leaders of Canadian thought, on the value of geological knowledge, that is impressive in its continuance dawn to this date. There seems always to have been before our people the realisation that large stretches of Canada are unfitted for agricultural settlement, and that our glaciated areas, the barrens and tundra of the North, and our extensive mountain ranges, had promise of compensating mineral content which the geologist and the prospector, labouring together through the years, would disclose. The Geological Survey is one of Canada&apos;s oldest public services, distinguished by an unimpaired tradition of honourable and useful labour. Founded in 1843, under William Edmond Logan, not yet &apos;Sir William&apos;, one year after the Act of Union, it was directed by him until 1869, or into the early years of Confederation, so that the early years .of the Survey were also, politically, the formative years of Canada, as we know her today.

Jan 1, 1932

By P. A. Peach, W. H. Gross

The modern economic geologist in Canada is well equipped to apply geological, geochemical or geophysical techniques in the exploration for ore. Recently, great advances have been made in geophysics and geochemistry, and a large number of new orebodies have been discovered by these methods. An attempt is made in this paper to show that there has also been a considerable advancement in geological knowledge and that the most effective application of geophysics and geochemistry often occurs in areas already considered geologically favourable for the occurrence of ore. Ali exploration methods sooner or later suffer from diminishing returns. Therefore, as time goes on, one can expect to see the application of some of the more subtle or refined geological techniques that are presently being developed.

Jan 1, 1967

By M. Reda

Because of the adverse environmental effect of Chromate, Molybdate ions had been investigated as replacement for Chromate and the results had shown not to be encouraging. Film deposited from peroxopolymolybdate (from reaction of Molybdenum meta, with excess Hydrogen Peroxide), are more robust than that deposited from molybdate solutions. This was shown to be due to higher fraction of Mo (IV) and Mo (V) that form from Mo (VI) in the peroxopolymolybdate deposited film than the film deposited from Molybdate solutions. The peroxopolymolybdate film contains 40% un-hydrated molybdic acid, tetraperoxodimolybdate and tetra peroxo tetra molybdate. The protective properties of peroxopolymolybdate were shown to be due to the effectiveness of the un-hydrated molybdic acid.

Jan 1, 2010

By M. Lahtinen

Traditionally, there have been three main methods for iron removal in the hydrometallurgical production of zinc. These methods are atmospheric precipitation of jarosite or goethite and pressurised precipitation of hematite. Jarosite precipitation is without doubt the leading and the most commonly used technology for iron removal. However, jarosite precipitation has some drawbacks, such as a low iron content (and, thus, high residue volume), high moisture content after filtration and often a high zinc content. These features make any environmentally acceptable way of using or disposing of jarosite more expensive, as compared to hematite and goethite. The importance of environmental regulations has grown in the zinc industry during the last decade, which will have an increasing effect on new investments. Hematite has several advantages over jarosite, such as a high iron content, low moisture and low zinc content. An important advantage of hematite is that it is suited for further use in the cement industry. However, until now the need for autoclave equipment has limited the spread and implementation of hematite precipitation in the zinc industry. Outokumpu Technology Oy has recently developed an alternative method for iron removal, which is the atmospheric precipitation of hematite. A patented method for precipitating hematite at atmospheric pressure is presented and compared with conventional methods for iron removal. The process conditions, the quality of the hematite precipitate and the environmental aspects are also discussed.

Jan 1, 2006

By J. E. Moran

A groupd of French capitalists, La Compagnie Française des Mines d&apos;Or du Canada, has undertaken the considerable task of developing Otter creek, in the Atlin district, B.C., by hydraulic mining methods. It has long been known that the gravels of this stream carry sufficiently high values in gold to make it attractive as a mining venture, but it was impossible to ignore the existence of formidable natural obstacles to hydraulicing them, and these needed to be taken into serious account before embarking upon any costly programme of development. The tide to the Otter Creek leases was originally held by Mr. H. Maluin, a French engineer well known throughout the north, to whom was to fall the task of financing whatever programme might be decided upon. It was he, too, who would have to assume the responsibility of finally passing judgment upon the practicability of the various devises for overcoming the adverse natural conditions. With an infinite attention to detail, which I believe to be a characteristic of the French people generally, he studied his problem and was finally able to submit to his financial backers a programme which left the very minimum possible to the hazard of accident or chance. Dr. Mandy, on his visit to Otter creek this season, expressed the opinion that our method of opening this difficult creek presented certain features which might be successfully applied in placer operations elsewhere in British Columbia, and it is largely for this reason that the present paper has been prepared. I shall set forth, as well as I can, the practices which have enabled us to overcome rather easily some of the obstacles which nature had unkindly placed in the path which we must take. The natural flow of water in Otter creek is far too little to deal success-fully with the rather excessive amount of glacial drift overburden which lies directly over the gold-bearing gravels. For this natural defect, the only remedy was to procure more water. This we have clone through a system of flumes and ditches, totalling between ten and eleven miles in length, which bring to the mine a supply of water adequate for our needs.

Jan 1, 1932

By G. T. Lapidus, A. Garcés, O. J. Restrepo

"Colombian nickel laterites have historically been processed by pyrometallurgy. However, due to the depletion in ore grades, alternative processes are required. Hydrometallurgical processes, such as pressure acid leaching, have been proposed as alternatives to extract nickel from deposits with suitable characteristics. Such a leaching process requires high concentrations of acid to achieve acceptable extractions, and is not selective. In this study, an alternative aqueous alkaline glycine system has been employed to evaluate the leaching behaviour of a Colombian nickel laterite which contains 1.15% Ni, 0.12% Co and 41.1% Fe. Additionally, the effect of the addition of chloride ions, the use of a reducing agent and the application of a pre-treatment to improve the extraction of nickel were evaluated. Extractions of 4.63% Ni, 42.16% Co and 0.33% Fe were obtained using a 1M solution of glycine at pH 9. In addition, an increase in nickel extraction from 4.63% to 25.68% was achieved by applying a pre-treatment to the sample. The results show that even though nickel dissolution was much slower than in acid leaching, it was selective over other metals such as iron, proving the proposed method to have potential as a process for the extraction of nickel from Colombian laterites.INTRODUCTION Before 2010, most of the industrial operations used pyrometallurgical processes for the extraction of nickel, mainly in saprolitic regions of deposits, with greater contents of the metal. Nevertheless, due to the gradual depletion of such deposits, different hydrometallurgical processes have been studied as alternatives to process those nickel laterites with low grade and those which present problems of refractoriness due to the presence of acid consuming materials (McDonald & Whittington, 2008; Oxley & Barcza, 2013; Wang et al., 2012). However, such leaching processes require high concentrations of acid to achieve acceptable extractions and they are not selective. Facing lateritic nickel ore deposits containing high levels of acid consuming materials, an alkaline leaching medium becomes an advantageous alternative over acidic media, due to the increase in selectivity and decreased corrosiveness and reagent consumption (Tanda, Eksteen, & Oraby, 2017). Unlike conventional acidic reagents used for metal recovery, alkaline reagents can selectively dissolve the desired metal, leaving in the solid residue other elements such as iron, magnesium and aluminum, which are problematic in subsequent stages of metals separation and recovery. Furthermore, there are no serious corrosion problems associated with alkaline leaching, even at higher reagent concentrations, or at elevated temperature and pressure (Ntumba Malenga, Mulaba-Bafubiandi, & Nheta, 2015)."

Jan 1, 2017

By K. Bullock, M. Levesque, G. Lyle, D. L. Millar

ABSTRACT The options for reducing the carbon footprint of energy use in mining fall into three categories of activity: i) reducing demand, ii) improving energy utilization, and iii) adopting low carbon energy technologies. In addition to the environmental imperative, the economic case for these activities gains higher priority as the prices of electricity, gas, and liquid fuels increase. Low-carbon, energy-saving technology options that are available to mining industry companies lead to projects with return rates that must compete alongside other capital-intensive projects considered by mining company boards. Energy projects frequently involve longer payback periods and lower rates of return than those of competing bids for capital, such as new mineral property developments. For energy services companies that specialize in the financing, construction, efficient operation, and maintenance of energy projects, the same returns and payback periods can be considered acceptable or even attractive.

Jan 1, 2012

By I. Caraconcea, M. Cousineau, S. Gariepy

"Several base metal plants operate in low grade/high tonnage conditions which impose strict cost control on all fronts for their operations to remain profitable. This leads to decisions regarding plant design, procurement, operations and maintenance that often favor cost minimization over value optimization. This may hinder the representativeness of the metal accounting systems while this should be a priority in a low margin environment. Such poor representativeness not only creates confusion in plant scheduling but can also hide suboptimal metallurgical performance. Furthermore, this situation can run undetected for a while since one dominant feature of a poor metal accounting system is its poor self-awareness. During their practice, authors have particularly identified measurement bias and reproducibility, as well as their impact on metal recoveries as areas of concern. These issues have not been extensively reviewed in the specific context of precious metals in base metal plants. Pragmatic solutions are proposed either at the design stage for a new project or to retrofit an actual operation. These solutions should be based on a business analysis that set a value of information matching the contribution of precious metals as well as the potential to use such information to act toward increasing plant profitability. Conclusions are that trade-offs are an inherent part of the design/audit/retrofit of any metal accounting system in any plant processing either base or precious metals. However, compromises must be evaluated on economic/technical ground.INTRODUCTION Every mineral processing plant must produce metal accounting reports (Morrison, 2008) where estimated saleable metal flows and inventories are published. These metal accounting reports are delivered to a variety of stakeholders who use them for internal management purposes (day-to-day plant production planning, plant operation optimization, capital spending, etc.) as well as for external management (royalty settlements, tolling agreements, etc.). Hence, there should be no doubt that state of the art metal accounting is instrumental for mining companies to reach and sustain high-quality corporate governance (Gaylard, Randolph, & Wortley, 2014). However, producing a metal accounting report involves much more than just printing it (Lachance, Leroux, & Gariépy, 2015a). The underlying metal accounting system (Figure 1) is responsible not only for the reliable production of the metal accounting reports but also for the quality of the outcome. As such, the crucial tasks of its design/audit/retrofit should neither be seen as ancillary nor be left as an afterthought."

Jan 1, 2017

By George Langford

Introduction The manufacture of ductile beryllium is one of the most interesting problems confronting the metallurgist today, and one which becomes more acutely in need of resolution as the uses for beryllium increase. Beryllium belongs to the hexagonal group of metals along with zinc, magnesium, and cadmium. The melting point of the metal is about l,280°C. ± 5°C. Due to its brittleness, the metal&apos;s chief use is as an alloying agent in copper and iron. The very low absorption coefficient of beryllium for x-rays makes the metal ideal for x-ray windows, and, similarly, because of its low capture cross-section for neutrons, the metal holds a preferred position in the field of nuclear physics. Modern x-ray diffraction methods were responsible for explaining the mechanism whereby zinc metal, although brittle when cast, could be made ductile at room temperature. The diffraction patterns of zinc and magnesium indicated the importance of the parts played by recrystallization and preferred orientation in this mechanism. It was with this in mind that an Investigation into the recrystallization and preferred orientation of beryllium was undertaken. The investigation, after a series of experiments were conducted involving cold-working and annealing, yielded the recrystallization temperature curve for beryllium. Both the texture of preferred orientation and the effect of recrystallization on this texture when subjected to compressive stresses were also determined. W. A. Alexander, J. K. Swinton and L. M. Pidgeon, in their investigation on The Recrystallization Temperature of Beryllium (C.I.M., Trans., Vol. L, 1947, pp. 657-664), utilized the Brinell ball as a means of cold straining the metal. Sufficient strain was developed to estimate the recrystallization curve for the metal. However, in order to determine the lowest recrystallization curve, as well as to develop a preferred orientation structure, larger deformation than that possible with a Brinell ball was required. The plastic deformation of beryllium can be carried out at an elevated temperature above 700°C. Above 850°C., the metal is quite ductile and can be readily compressed or extruded.

Jan 1, 1948

By P. H. Tolcher

Canada, as the Free World's largest mine producer of zinc and the third largest mine producer of lead, has a vital interest in the future growth in demand for these metals. This paper traces the development of lead and zinc consumption in the last two decades, both on a total-Free-World basis and by major market areas. How Canada, as a major mine producer, has shared in this growth is also indicated. In addition, future consumption for both metals in the current decade of the 1970's is fore-cast. The demand these projections will make on Free World mines, particularly on Canadian mines, is examined. Some of the opportunities and challenges the Canadian mining industry will likely face during this period are also dealt with.

Jan 1, 1971

By K. Svens, M. Lahtinen, L. Lehtinen

"Outotec&apos;s direct leaching process is an atmospheric leaching process for sulphidiczinc concentrates. The direct leaching process, based on special leaching reactors developed by Outokumpu and leaching know-how, is the most economical way to produce electrolytic zinc. The newest industrial-scale application of Outotec&apos;s direct leaching process will be started up in 2008 in China at Zhuzhou smelter. The process isintegrated to the existing production plant, replacing part of the old production facilities by modern technology and increasing the production capacity significantly. The process equipment supplied by Outotec includes also tailor-made reactors designed on the basisof the work and experience of Outotec Research Centre."

Jan 1, 2008