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By R. J. C. MacDonald

"The first recorded discovery of placer gold in Canada was on the Chaudiere River in Quebec's eastern townships in 1832 and the first major production came from placer deposits in British Columbia in 1858 (Verity 1974). Placer deposits were the major source of gold until the late 1890's, although lode deposits were found in Nova Scotia in 1862. In 1896 the Klondike Gold Rush commenced with the discovery of gold by Henderson and Carmack in the Yukon. The peak was reached in 1900 when over one million ounces of gold valued at approximately $22.3 million were recovered. With the exhaustion of the easily accessible deposits, more capital intensive operations were necessary such as those initiated in 1906 by the Yukon Gold Corporation. This giant dredging operation continued to produce until 1966. Today only a few small operations remain.The development of Canadian lode gold mining began in earnest around 1900 when the railroads were opening up the interior and western part of the country. At this time many discoveries occurred, particularly where mineral outcroppings were near surface. Tremendous impetus for exploration and the reopening of former producers followed the elimination of the gold standard by Great Britain around 1931, and more importantly the United States in 1933, with subsequent stabilization of the price of gold at $35 per ounce in 1934. Prior to this the price of gold was basically unchanged since 1717, approximately, $20 per ounce (Verity, 1974; Green, 1973).The depression of the 1930s adversely affected most industries, however for the gold producers it was a very profitable time. Prices of materials and equipment declined and labour was cheap and plentiful. Interest in gold mining was further stimulated in 1936 when a three year tax exemption was declared for all new metal mines. In 1938 a decline in the value of the Canadian dollar relative to the U.S. dollar benefitted the industry. The second world war provided yet again further incentive for gold production and in 1941 Canadian gold production reached a high of approximately 5.4 million ounces. This figure was not surpassed until 1991 when approximately 5.6 million ounces were produced (Natural Resources Canada, 1996 )."

Jan 1, 1998

By C. J. Van Treeck

PGE concentrations of 18 g/t occur in the pyroxene rich rocks at the Union Bay Alaskantype complex. This PGE enrichment is hosted in magnetite veins. These veins cross magmatic layering and have an irregular morphology in both outcrop and thin section. Fe-Ti oxide geothermometry suggests that this mineralization took place between ~700-400°C. A variation in the amount of ilmenite and Mg- Al spinel exsolution in magnetite correlates with temperature estimates, lower temperature magnetite has less exsolution. Hydrous silicates form an alteration envelope around magnetite veins with a formation temperature of <575oC, vary with temperature, and contain appreciable amounts of Cl. Interaction of a PGE-Fe-Cl rich fluid with clinopyroxene increased the fluids pH and decreased PGE and Fe solubility depositing a PGE enriched magnetite within the Pyroxenites and Olivine Pyroxenites of the Union Bay complex.

May 1, 2003

By G. Chi, A. Solomon, J. Lai

"The Buffalo gold deposit is a small deposit consisting of auriferous quartz-tourmaline veins within a granodiorite stock in the Red Lake greenstone belt. This study aims to characterize the mineralizing fluids through fluid inclusion and stable isotope analyses and to compare them with those of the world-class Campbell- Red Lake deposit. Four types of fluid inclusions were recognized, including carbonic, aqueous-carbonic, aqueous, and halite-bearing aqueous, with the carbonic type being the most abundant. Raman analyses indicate that the carbonic phase mainly consists of CO2, with minor amounts of N2 and CH4, and rarely detectable H2S. The homogenization temperatures of the carbonic inclusions range from -41.7° to 30.9°C. The homogenization temperatures and salinities of the aqueous, halite-bearing aqueous, and aqueous-carbonic inclusions are 130° to 276°C and 9.7 to 23.6 wt.% NaCl equiv., 155° to 207°C and 32.9 to 42.3 wt.% NaCl equiv., and 215° to 357°C and 8.3 to 19.7 wt.% NaCl equiv., respectively. The d18OVSMOW values of tourmaline range from 8.2‰ to 9.0‰, and those of quartz from 11.4‰ to 11.9‰, with estimated fluid temperatures from 323° to 399°C based on the quartz-tourmaline isotopic geothermometer. It is postulated that separate CO2-dominated and aqueous fluids intermittently invaded the fracture/vein system in response to fluid pressure fluctuations, with limited mixing. The CO2-dominated fluid, previously recognized in Campbell-Red Lake as the main mineralizing fluid, is inferred to have been derived from deeper parts of the crust. This deep CO2-dominated fluid reservoir might have been a common source for gold mineralization in the Red Lake greenstone belt. Le gîte aurifère Buffalo est un petit dépôt composée de veines de quartz-tourmaline à l’intérieur d’un stock de granodiorite dans la ceinture de roches vertes de Red Lake. Cette étude vise à caractériser les fluides impliqués dans la minéralisation par les inclusions fluides et par les isotopes stables ainsi que de les comparer avec ceux du gîte de classe mondiale de Campbell-Red Lake. Quatre types d’inclusions ont été notes, incluant des inclusions carboniques, aqueuses-carboniques, aqueuses et aqueuses avec halite, les inclusions carboniques étant la variété la plus abondante. Les analyses par spectroscopie Raman indiquent que la phase carbonique consiste principalement en CO2, avec des quantités mineures de N2 et de CH4, et rarement avec des quantités mesurables de H2S. Les températures d’homogénéisation des inclusions carboniques vont de -41.7° to 30.9°C. Les températures d’homogénéisation et les salinités des inclusions aqueuses, aqueuses avec halite et aqueuses-carboniques sont varient de 130° à 276°C et de 9.7 à 23.6 poids.% NaCl équiv., 155° à 207°C et 32.9 à 42.3 poids.% NaCl équiv., et de 215° à 357°C et 8.3 à 19.7 poids.% NaCl équiv., respectivement. Les valeurs de d18OVSMOW pour la tourmaline vont de 8.2 à 9.0‰, et celles du quartz de 11.4 à 11.9‰, avec une température estimée du fluide entre 323° et 399°C sur la base du géothermomètre isotopique quartz-tourmaline. Il est postulé qu’un fluide riche en CO2 et un fluide aqueux distinct ont envahi le système de fractures/veines par intermittence en réponse à des variations dans la pression des fluides, et qu’il y a eu peu de mélange. Le fluide riche en CO2 est également observé à Campbell-Red Lake ou il est le fluide minéralisant principal, il est présumé être dérivé de portions plus profondes de la croûte. Ce réservoir profond de fluides riches en CO2 pourrait être la source commune des minéralisations aurifères de la ceinture de roches vertes de Red Lake."

Jan 1, 2009

By Tapiwanashe Chenje, David Hewitt, Peter Radziszewski

"Steel media wear is a major cost component in mineral processing. In the case of existing operating mill, steel media wear prediction can be used to help compare the performance of steel media from different suppliers before completing marked ball tests. It can also be used to investigate how ores from different site of a given mine affect steel media wear. In the case of Greenfield cases, steel media wear prediction can be used to estimate the cost of steel media for a given feasibility study.This paper presents a wear testing and prediction methodology that ties together abrasion wear and corrosion wear testing results through the use of a simplified discrete element charge motion model. The experimentation dimension to this methodology takes samples for steel media, mine site ore and water to determine abrasive and corrosive wear parameters of a given media, ore, water set.The test methodology development is illustrated along with a comparison of wear predictions with observed wear rates in some operating mills. A case study is included that illustrates how this methodology was used to estimate steel media wear performance. The paper closes with a discussion on the use of parts of the experimental methodology to investigate other abrasive wear conditions such as liner wear, paste backfill piping and ore breakage as well as avenues for future test development.INTRODUCTIONThe cost of comminution processes represents a significant part of the overall costs of a mining operation. Grinding media/liner wear alone accounts for 15-25% of the total operating cost. The annual steel grinding media consumption is approximately 2.5 mtpa or 0.3% of total world steel production [Smorgon Steel Group, 2005]. Using an estimated grinding media cost of about US$0.75/kg [Halbe and Smolik, 2002], gives a media cost of over US$1.875 billion per annum. Mining continues to shift towards exploitation of lower grade ores as the higher grades get depleted. These low-grade ores require finer grinding for the liberation of the value minerals, and hence it can be assumed that grinding media consumption will also continue to rise.The Bond abrasion test, dating back to 1963, [Weiss, 1985] is still used to estimate the total mill media wear. This is a purely empirical test based on the ore. From Bond abrasion index tests, it is possible to determine a wear rate using the following function:"

Jan 1, 2009

By B. Lueger, D. Shen, M. Sedighy, R. Rand, R. Saleh, J. Cheung, M. Rifai, I. Khan, W. Sauri, D. Setianto

The world’s first active power demand stabilization system for a 3-electrode electric arc smelting furnace was commissioned at PT Vale Indonesia in December 2012 on Furnace No. 2 using an SPLC (Smart Predictive Line Controller). The SPLC technology in combination with the Furnace No. 2 rebuild and other upgrades has enabled PT Vale to increase the electrical input to the furnace by up to 20% on a stable and sustainable basis by eliminating peak powers that overload and trip out the electrical equipment, and by reducing power unbalances. The SPLC technology maintains smooth arc power using a continuously variable thyristor controlled series reactor. The SPLC compensates variations in the furnace arc with predictive changes in the circuit reactance at a speed of up to 60 times a second. The system started up quickly and has been shown to be easy to operate and maintain by PT Vale. PT Vale’s Operations Team has been testing the new system at set points of up to 90 MW on the newly re-built Furnace No. 2. Over the last 12 months, the throughput of Line 2 has increased by approximately 10% on an annual average; however, debottlenecking in other design areas of the operation is required in order to achieve 90MW operation on a sustainable basis. This outstanding success results from a combination of the furnace and other upgrades, the SPLC active power stabilization, and the skill of PT Vale in quickly adopting new technologies and maximizing the combined benefits of each technology in their operation.

Jan 1, 2014

By A. A. Beland, R. J. Dawson, S. Shewchuk

"Shovel buckets, scraper blades, dipper teeth, mine car wheels and hammermills are examples of equipment which require routine maintenance due to abrasion. Service life can be extended by the use 0/hard/acing and buildup materials. Mining and milling applications are described and field welding procedures discussed.A high-stress abrasion test used to select hard/acing and buildup materials/or hammers in a hammermill is described in detail. Field tests of the selected alloys confirmed their performance, and maintenance records showed a significant saving in down time and cost.The relationship between the abrasion resistance of the alloys and their hardness, work hardening, composition and microstructure is summarized. IntroductionLarge volumes of ore are handled daily by the mining industry. The abrasive nature of most ores results in extensive wear to both handling and processing equipment. If such wear is neglected it may cause lost production time and also, in extreme cases, require the complete replacement of expensive equipment. The well-planned maintenance of components subject to abrasive wear by means of buildup materials and hard facing can result in substantial economic benefits. Such benefits can , however, only be realized through the correct choice of welding process, consumables and deposition methods available to maintenance personnel. Hardfacing MethodsHardfacing is applied by a variety of methods; the three most widely used being arc welding, oxyfuel gas and thermal spraying. Table 1 summarizes the major processes used within each method. Filler metals in the form of rod, wire or powder are necessary to fulfill the individual requirements of each process. The filler rods are available in the cast form or, in the case of ductile metals or alloys, as wrought rod or tube. All types are supplied bare or flux covered. Wire is supplied in two forms, drawn flux cored and drawn solid. Powder filler metals are available in many metals or alloys; they may be simple mechanical mixtures or prefused and atomized alloys made to a specific size range and shape for optimum results for each applicable process."

Jan 1, 1980

By H. Zhu, Y. Sato, O. Takeda, K. Nakano

Recycling of rare earth magnet wastes is essential to insure the stable supply of rare earth resources. For the development of a novel recycling process, the removal of rare earth oxide from an off-spec alloy magnet was investigated by melting the alloy magnet at 1503 K together with fluoride flux, LiF-50 mol% NdF3 and LiF-?25 mol% NdF3-25 mol% DyF3. After melting, the separation of magnet alloy from the fluoride flux was achieved, and neither suspension of alloy in the flux nor suspension of flux in the alloy was observed. Oxygen concentration in the alloy decreased from 5000 mass-ppm to 160 mass-ppm by utilizing 1.5 times of equivalent amount of flux needed to completely dissolve the oxide. The investigated process is suitable for mildly contaminated waste such as a used (end-of-life) magnet because of its simplicity, low energy consumption and small limitation on location for operation.

Jan 1, 2014

By L. Hanschar, C. Bwalya, E. Mokola, K. Musonda, A. Makayi

This paper describes the installation, commissioning and operation of porous plugs featuring nitrogen gas purging in both Anode Furnaces at the Kansanshi Copper Smelter (KCS), a greenfield copper smelter which commenced operation in March 2015. The decision to install porous plugs was taken in November 2016 and the facilities were successfully commissioned on both anode furnaces in October 2017. The project was successful and has demonstrated the following process improvements: 12.2% reduction in main burner fuel consumption Larger average charge size, due to fewer accretions; 17 minute decrease in average refining cycle times Improvements in slag skimming operations Improved casting rates INTRODUCTION Porous plugs The application of porous plug technology in copper smelter anode furnaces is well established around the world. Vukovic and Gamweger (2017) and Wallner (2004) noted that the stirring and mixing action induced by the injection of inert nitrogen gas into the molten copper via porous plugs has potential benefits in the following areas: Homogenization of the temperature and composition of the molten copper resulting in Reduced fuel consumption Less tendency to overheat slag (reduced risk of refractory attack) Less slag produced with a lower degree of oxidation (lower rate of refractory wear) Less tendency for buildups to form Improved environmental performance (produce low sulphur blister at Peirce Smith converters) Elimination of buildups inside the furnace and potential for larger charges per cycle Reduced processing times and potential for shorter cycle times More efficient skimming of anode slag Shorter skimming time Less copper carry over to Peirce Smith converters Very little slag remaining in the furnace (reduced potential for buildups to form)

Jan 1, 2019

By D. Wolfe, R. Cleminson

"The Aurora North mine has been operating for more than ten years, and is the source of over half of Syncrude’s bitumen production. The hydrotransport systems at Aurora experience high rates of wear, and mission lengths on current slurry pumps are nominally 1,500-2,000 hours. Recent work has enabled a better understanding of the significant adverse effect of large particle impingement damage to impeller vane leading edges - which is the known life determining issue for Aurora hydrotransport pumps. A new pump design has been developed and installed at Aurora, incorporating significantly increased impeller diameter and pumping vane lengths. The new pumps are expected to triple Aurora’s previous mission length for hydrotransport pumps. Part II of this paper will share actual hydraulic and wear performance observed in the first several months of operation, and draw comparisons relative to what was expected for these pumps in design / development.INTRODUCTION Slurry Pumps are Critical Equipment at Syncrude Slurry pumps are a key component in Syncrude’s operations. In a typical Aurora application, each 5000 HP pump stage helps move over 8,000 dry tonnes per hour of oil sand, plus an equal volume of process water that has been added to create the slurry. The average impeller life in oil sand hydrotransport service at Aurora has been nominally 1,500 to 2,000 hours, or 12 to 16 million tonnes of oil sand pumped. Generally, the slurry pump application at Aurora has proven very difficult to improve due to the unique combination of high sand abrasivity, 125 mm (5”) large particle top size (lumps), and high flow rate relative to basic pump size; a factor that results in unduly high impeller vane leading edge speeds for the service conditions."

Jan 1, 2014

By H. Utsunomiya, J. Su, K. S. Tamimi, S. Yue, M. Sanjari, L. Kestens, Hara, A. S. Kabir, R. Petrov

Manufacturing of thin sheet is difficult in industries. Some approaches, such as small-draft multi-pass rolling, intermediate annealing, isothermal rolling and high-speed rolling were proposed to overcome the deformability. In this study, different rolling speeds from 15 to 1000 m/min were employed to twin rolled cast AZ31B magnesium alloy to different reductions. The results show thatAZ31B sheets rolled at 15 m/min and 100 °C has fractured for reductions of more than 30% per pass. However, by increasing the rolling speed to 1000 m/min the rollability was improved significantly and the material can be rolled to reductions of more than 70% per pass. The high speed and heavily deformed materials are fully recrystallized even at 100 °C.

Jan 1, 2014

By Manqiu Xu

"Ore grades are decreasing and ore deposits are becoming more complex. In order to make a sound economical decision about a mining project, metallurgical testwork must be carried out. A few large “representative” samples cannot represent the metallurgy of a large ore body and a large number of samples reflecting variation in ore head grades and in mineralization types must be obtained for proper metallurgical studies, including flowsheet development for a greenfield project. A relationship can be established between the recovery of valuable minerals and ore grade for each mineralization type. This relationship can be used to establish a correlation between values recoverable and values contained in the ore body that can include multiple pay metals. With this information, a sound economical decision can be made about the viability of a large mining development project.INTRODUCTIONThe demand for minerals today is historically high as many countries are being rapidly industrialized. The supply for these minerals is not necessarily running short. However, it is widely accepted that the world today is running short of the easy to mine and easy to process ore deposits. As ore grade is decreasing and ore mineralogy is becoming more complex, metallurgical testing must be fully conducted in order to make a sound economical decision about a mining project. For a high-grade and high-quality deposit, it is hard not to make a good profit even with low metal prices. For a low-grade and hard to process deposit, the profit margin is much lower and is dependent on the throughput and the recovery of valuable minerals. The recovery of valuable minerals is a function of ore grade and mineralogy and it must be experimentally determined for a given processing option.At Vale Base Metals Technology Development, metallurgical testing for an existing operation or brownfield project is termed as Ore Evaluation, while metallurgical testing for a greenfield project is termed as Flowsheet Development (Xu, 2011). In the past, metallurgical testing involved a few large composite samples for lab and pilot plant testwork. As ore deposit becomes less homogeneous and more variable, a few large composite samples cannot represent the metallurgy of a large ore body. In addition, useful information about the deposit such as zones of “impurities” or floatable rock minerals would not be obtained. Different processing strategies could have been developed if the locations and sizes of these zones were known in advance. For proper metallurgical studies, a large number of samples reflecting variation in ore head grades and in ore mineralization types must be used. A relationship can be established between the recovery of valuable minerals and ore grade for each mineralization type. This relationship can be used to estimate values recoverable in the ore body that can include multiple pay metals. Ultimately, the recovery verses ore grade relationship will be used in business decision-making."

Jan 1, 2013

By J. E. Scott, L. M. Heaman, R. A. Creaser, G. S. Salazar

"Schaft Creek is a calc-alkaline porphyry Cu-Mo-(Au) deposit located in northwestern British Columbia. The deposit formed in a volcanic arc setting, likely on a back-arc rifted continental fragment. It is hosted by Late Triassic basaltic to andesitic volcanic rocks of the Stuhini Group (Stikine Terrane), and is associated with porphyritic granodiorite dikes emanating from the nearby Hickman batholith. The age of the Hickman batholith is approximately constrained here by a composite U-Pb zircon date of 222.1 ± 9.6 Ma, which is in broad agreement with a well-constrained age for mineralization at Schaft Creek of 222.0 ± 0.8 Ma (Re-Os molybdenite). The deposit is in most respects typical of calc-alkaline porphyry systems, but displays silica-poor sericite-chlorite alteration in mafic country rocks in place of classic phyllic altera¬tion. The deposit comprises three distinct, but related, zones: the northern Paramount zone, the Main zone, and the West Breccia zone. Two phases of mineralization are observed. The first phase occurs as hydro-thermal veins and breccias, and minor disseminations. It consists of bornite, chalcopyrite, molybdenite, and pyrite with potassic and sericite-chlorite alteration. The second phase is minor and consists of veins of molybdenite ± specularite, as well as Cu-Pb-Zn sulfide veins without any significant corresponding alteration. Extensive structural modification has affected the deposit both during and after its formation.Schaft Creek est un gîte porphyrique de Cu-Mo-(Au) calco-alkalin situé dans le nord-ouest de la Colombie Britannique. Ce gîte s’est formé dans environnement d’arc volcanique, probablement situé sur un fragment continental bordé par un bassin d’arrière-arc. Le gîte est encaissé par les roches volcaniques basaltiques à andésitiques du Groupe de Stuhini (Terrane de Stikine) d’âge Triasique tardif, et est associé à des dykes de granodiorite porphyrique provenant du batholithe de Hickman avoisinant. L’âge du batholithe de Hickman est estimé par un âge U-Pb composite sur zircon de 222.1 ± 9.6 Ma, lequel est grossièrement en accord avec l’âge de la minéralisation de Schaft Creek, estimé a 222.0 ± 0.8 Ma (Re-Os sur molybdénite).Ce gisement, bien qu’à plusieurs égards typique des systèmes porphyriques calco-alcalins, présente une altération en séricite-chlorite pauvre en silice dans l’encaissant mafique a la place de l’altération phyllique classique. Ce gîte comprend trois zones distinctes bien que connexes : la zone Paramount au Nord, la zone Principale et la zone West Breccia. Deux phases de minéralisation sont observées. La première phase se présente sous forme de veines et de brèches hydrothermales ainsi qu’en disséminations mineures et consiste en bornite, en chalcopyrite, en molybdénite et en pyrite avec une altération potassique et en séricite-chlorite. La seconde phase est mineure et consiste en veines de molybdénite ± spécularite ainsi qu’en veines de sulfures de Cu-Pb-Zn sans association à une altération particulière. Le gisement a été profondément modifié par la déformation a la fois durant et après sa formation."

Jan 1, 2008

By Hossein Aminian, Daniel Hodouin, Claude Bazin, Claude Jacob

"Solvent extraction followed by electrowinning (SXEW) is an economical option for the processing of low grade and oxidized copper ore. Phenomenological models were developed to simulate the copper solvent extraction and the electrowinning processes. The two models were linked together to make a SX/EW simulator. The simulator is used to predict the operation of the mines Gaspe pilot plant put in operation in 1996. Results confirm the potential of the simulation that would subsequently be used for student training, process optimization and to assess the performances of control strategies.INTRODUCTIONSolvent extraction followed by electrowinning (SXEW) has become in the last two decades a key process for the recovery of copper from solution obtained by leaching low grade copper ore. Several operations have been commissioned in North and South Americas in the last decade (Arbiter, 1994). In Canada, Gibraltar Mine (Scott, 1991) operates a SX plant followed by electrowinning (EW) to produce copper cathode from leached low-grade ore dumps. From 1996 to 1997 Mines Gaspe operated a pilot plant to test the economical feasibility of leaching an oxidized copper ore, followed by solvent extraction and electrowinning of copper. Despite copper SX/EW processes have the reputation of being low cost operations, plant engineers should always look at way to make the plant more efficient. Process models provide an economic platform to learn, control and ultimately optimize the operation of a plant.Several models have been independently proposed to simulate the SX process (Cadman and Hsu, 1970; Medina Gomez, 1980; Wilkinson and Ingham, 1983; Garcia et al., 1988; Aminian et al., 1997) and the EW process (Bryson, 1981; Barton and Scott, 1992; Barton and Scott, 1993). However few papers, if any, deal with the integration of the two process models into a single simulator of a SX-EW plant. This paper describes the development of an integrated simulator for the SX-EW process and shows some steady-state simulation runs of an actual SX-EW pilot plant. The paper consists of four sections. The first section shows the general layout and principles of operation of a SX-EW plant.The second section describes the SX model while the third section deals with the process model used for the copper electrowinning process. The last section shows how the two process models are linked to simulate the operation of the Gaspe pilot plant."

Jan 1, 1999

By H. P. Jacobi

"INTRODUCTIONPine Point Mines, operated by Cominco Ltd., is located approximately 65 miles east of Hay River, N.W.T. on the south shore of Great Slave Lake.The milling operation started in the fall of 1965 with a capacity of 5,000 tpd. An addition was put into operation late in 1968 to bring the nominal capacity up to 8,000 tpd. The present milling rate is 11,000 tpd.With a feed grade of approximately 2.9% Pb and 6.0% Zn the annual concentrate production amounts to roughly 130,000 SDT of lead concentrate and 370,000 SDT of zinc concentrate for a total of 1/2 million tons of product.This tonnage is moved by railroad. Pine Point is served by the Great Slave Lake Division (G.S.L.) of the Canadian National Railways which connects to the Northern Alberta Railway System (N.A.R.) at Roma Junction, at Peace River, Alberta. The system in turn connects to the CNR and the CPR in Edmonton, Alberta. From here the concentrates move inland chiefly to Trail, B.C., with some shipment to other Canadian and U.S. smelters, and to the port facilities of Pacific Coast Terminals at New Westminster, B.C. for offshore export.This paper will focus on the problems associated with the movement of lead and zinc concentrates from Pine Point to port facilities on the west coast."

Jan 1, 1975

By Roxanne Scott

Outline ? Overview of Community Investment in the Mining Sector ? Emerging Good Practice: ?Strategic Integrated Community Investment? ? Assessing Local Context: ? Institutional Assessment ? Partnership Assessment Approaches to Community Investment Isolation: No proactive engagement in community development Ad hoc philanthropy: small infrastructure, sponsorships, donations Strategic philanthropy: Community proposes options for development Company decides what to do and carries it out, e.g. building schools, health posts, roads Strategic integrated community investment: ? Aligned with government/community development goals and priorities ? Communities and government involved in decisions and execution ? Focused on training and capacity building ? Partnerships ? Continuation in absence of company support Measured returns on investment

May 1, 2010

By Sergei Decterov, Peter Hayes, Evgueni Jak, Taufiq Hidayat, Denis Shishin

Copper smelter operations around the world are under sustained pressure to reduce costs and increase output. Through the provision of reliable data on fundamental properties of the chemical systems the opportunities for improvements of industrial copper production can be identified. Experimental and modelling studies on phase equilibria, thermodynamics of copper slag/matte/metal/gas systems have been combined into an integrated research program undertaken at PYROSEARCH. Experimental phase equilibria studies involve high temperature equilibration in controlled gas atmospheres, rapid quenching and direct measurement of compositions of equilibrium phases with electron probe X-ray microanalysis (EPMA). Thermodynamic databases development and modelling is undertaken using the computer package FactSage in conjunction with advanced models used for complex solution phases. Progressive development of these research methodologies has brought significant advances in characterisation of these complex systems, including a new optimised thermodynamic database for the copper-containing slag system Cu2O-Al2O3-CaO-FeO-Fe2O3-MgO-S-SiO2.The new data and models can now be applied to assist in improvements of the processes. The effects of changes to chemistry and process conditions within the smelting reactor can be examined. Several examples of new descriptions of the phase chemistry of the Cu2O-CaO-SiO2 and Cu2O-FeO-Fe2O3-SiO2 systems in equilibrium with metallic copper showing calculated and experimental data are presented.

Jan 1, 2014

By Jason J. Crowder

Presentation Outline ? Introduction ? Costs of ground support and rehabilitation ? Why post-failure rock mass properties are necessary ? The Rock Mechanics Problem ? Present State of Modelling and Instrumentation in Mining ? Case Study Background ??Williams Mine ? Deriving Parameters for Modelling from Instrumentation ? Results from Case Study ??Back Analyses ? Discussion of Research Impact t Summary

May 1, 2006

By R. E. Whitehead

"Alkali/alumina and MgO/alumina molar ratio plots graphically portray both chemical and mineralogical changes accompanying potassic, phyllic, argillic, chloritic, and alunitic alteration of quartz monzonites and granodiorites hosting porphyry (as well as lode and greisen) ore deposits. The molar ratio plots can be used to identify different types of alteration. In most cases, the identification based on molar ratios coincides with petrographic data. In those instances where the molar ratio and petrographic identifications do not agree, the mineralogy might need to be re-examined. Hydrothermal alteration studies using trace elements could benefit from the application of complementary alkali/alumina molar ratio plots.Le diagramme des rapports molaires alkali/alumine et MgO/alumine illustre clairement les changements chimiques et minéralogiques qui accompagnent les altérations potassique, phyllique, argillique, chloritique, and alunitique des monzonites à quartz et des granodiorites encaissant les gîtes de type porphyrique, ainsi que des veines et des greisens qui leur sont associés. Les diagrammes de rapports molaires peuvent être utilisés pour identifier divers types d’altération. Dans la plupart des cas, l’identification basée sur les rapports molaires est en accord avec celle basée sur les données pétrographiques. Là ou il y a désaccord entre les rapports molaires et les données pétro-graphiques, il peut être nécessaire de réexaminer la minéralogie. Les études de l’altération hydro-thermale accompagnées d’une étude des éléments traces auraient avantage à utiliser un diagramme des rapports molaires alkali/alumine."

Jan 1, 2009

Mine Evaluation Engineering , Operational and Social evaluation. Focus is on what opportunities are available. Social ??History ??Past Management Practices ??Community / Available labor force Mining Method / Equipment ??Competent rock ?little support required, no backfill ??Shallow mining ?ramp mining, no shafts or hoisting ??Large scale mining potential ??Simple rock breaking and crushing on surfaceMill Process ??Straightforward gold liberation process Create a Plan / Create a Team Following the feasibility 44-101. Key people were hired and a full operational Business Plan was developed. Focus is on how to get the job done. ??Scoping Study / Pre-Feasibility / Feasibility ??Operational Business Plan ??Hire key people ??Purchase key equipment

May 1, 2006

By C. A. Olivier

Le Ministère des Richesses naturelles du Québec has continued development work on the process/or direct reaction 0/sodium carbonate with lithium-bearing silicates(Canadian Patent No. 643,843). Recent process improvements have involved continuous pressure leaching, rather than batch leaching, and higher solution concentrations (over 55 g/l Li2CO3. These improvements have been demonstrated on a pilot scale operating on decrepitated spodumene from the Sullivan Mining Group&apos;s Quebec deposit. The new process is expected to be very competitive with the conventional sulphuric acid route. The improved flowsheet and main process steps will be described along with pilot-plant results.

Jan 1, 1979