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By D. Nower

"The supply of copper is expected to be at a large deficit in 2012. To recover from these deficits mining companies are required to maximize production and there is no better way to accomplish this than to optimize the use of their mobile mining equipment fleets. To optimize these fleets, each equipment type has to be monitored in its own unique way. Automation would not only improve production, but also minimize the safety risks and eliminate planning errors. The automated vibration monitoring of multiple systems on the shovel can determine the machine’s condition at all times. This reduces unplanned downtime and keeps critical shovels in production. This paper will discuss the details of how shovels can be successfully monitored, continuously. INTRODUCTIONP&H Mining, part of Joy Global, is the world’s largest manufacturer of above-ground mining equipment. Its electric rope shovels, such as Figure 1, with capacities up to 115 tons (104.3 metric tons), are used for high production loading in surface mines; its draglines, such as Figure 2, have bucket capacities to 160 cubic yards (122 cubic meters). P&H also produces blasthole drills, mobile mining crushers and other essential mining equipment. Headquartered in Milwaukee, WI, the company does business on every continent, except Antarctica. ECONOMIC FACTORSDue to the global demands for metals and power, mines are required to operate at full capacity. Mine operations cannot afford any critical assets to shutdown unexpectedly; depending on the ore type and quality, downtime for a single shovel can be as much as $300,000 per hour.Electric rope shovels are one of the most critical assets in open pit mining. They are very large, complex machines with DC or AC motors, multiple reduction gearboxes (some of them complex planetary) and multiple large rolling element bearings. This complexity, combined with the tough 24/7 service, results in too much unplanned shovel downtime, which can affect the entire downstream process."

Jan 1, 2012

By E. G. Joe

The continuing increase in costs for power and fuel are affecting significantly the cost of milling Canadian ores. In order to ascertain the scope and source of energy consumption in Canadian mills for further energy conservation opportunities, CANMET, in cooperation with the Canadian Mineral Processors, carried out a detailed survey on the metallic mineral processing plants. Sixty-seven mills representing almost 300 million tons of annual capacity participated in the survey. The results indicated that, in general, copper and iron ore mills, representing the bulk of the tonnage, consumed relatively low levels of energy per ton. Nickel-copper, zinc-copper and lead-zinc .ore mills were moderate in energy consumption, and uranium and some copper-lead-zinc mills reported much higher energy consumptions due primarily to the increased heat requirements of the ore pulp. Although plant heating costs varied somewhat with location, it was apparent that the lowest heating costs were achieved by those plants built with proper insulation and energy conservation design. If the cost per million British thermal units is taken as $2.00, the mill energy costs generally ranged from 40ft to $1.20 per ton.

Jan 1, 1979

By L. S. Jen

Canadian copper, nickel, zinc, lead and molybdenum mines are characterized by the mining of ores from which more than one metal is recovered. During the 1980s, approximately 15% of the gold, 25% of the zinc, 30% of the copper, 55% of the molybdenum, 80% of the silver and 90% of the lead produced from Canadian mines were produced as co-products and by-products of base metal mining operations. This trend is not expected to change significantly in the near future. The presence of co-products and by-products affects the level of production and the level of revenue from base metal mines in several ways: (I) in general, production of one base metal cannot be expanded or cut back without affecting the amount of production of another metal;(2) the commercial success of certain base metal mining operations depends on the substantial bonus revenues from co-products and by-products; (3) the quality and economic viability of many ore deposits are significantly improved by the presence of co-products and by-products; and (4) while coproduction is critical to the survival of some mines, bonus revenue from by-products can also be life saving to others during economic downturns. For these reasons, deposits with significant co-product or by-product values are likely to continue to be significant targets for exploration and for acquisition.

Jan 1, 1992

By Hugh K. Taylor

"With some justification, people have long complained about the indefinition of ore reserves. Perhaps they were led to expect too much; from former and easier definition practices in the once common underground mines with exposed and available assets, where the obsolete term 'ore in sight' was at least partly literal. But such mines have become rarer, and their underground development less affordable. For most projects, valuations and its definitions have thus been advanced from actual to prospective mines, leaving a very wide gulf between 'what is there' and 'what may happen to it'. This brings the double challenges of reduced geological and technical assurance and the protraction of economic uncertainties.This paper avoids the popular field of regional resources, being confined to what may possibly be mined within single or closely grouped deposits. For these, many estimates of tonnage and grade must be made, defined and declared long before assessment of feasibility; and the uncertainties of the latter make it an unsound base for defining the earlier quantities. Despite the best of intentions, implied or inferred promises may proveimpossible to honour.A simpler framework of definitions is suggested, to some extent reverting to an earlier dependence on supporting work rather than on opinions of economic assurance or future events that are more properly the functions of production and cash flow schedules."

Jan 1, 1994

By J. E. Carter, D. P. Wall

"This paper details the highlights of the open-pit and underground operations of Mclntyre Mines Limited in the Smoky River area of Alberta. Mining methods, operating equipment and manpower are outlined, followed by a discussion of reclamation and environmental control.IntroductionMcintyre Porcupine Mines Limited was incorporated in 1911 and for many decades was known primarily as a gold producer in the Porcupine district of northeastern Ontario. The company, however , has held coal leases in the Smoky River area, near Grande Cache, Alberta, since 1921. Preliminary studies were carried out in the region from 1959 to 1963. In 1964, Mitsubishi, a leading Japanese trading company, (on behalf of Mcintyre), investigated the area as a possible source of coal for the Japanese steel industry. The initial report concluded that Smoky River coal was of high quality, comparable with some of the best metallurgical coals in the world."

Jan 1, 1981

By S. Banisi, J. Marois, A. R. Laplante

"This paper compares the behaviour of gold and ore in the grinding circuit of Hemlo Mines Ltd. Particular attention is given to grinding kinetics, classification behaviour, and liberation. For grinding kinetics, laboratory grinding of gold flakes and silica, 840 µm to 1200 µm in size (14/20 mesh), was also performed to provide a standard for comparison and to study in a controlled environment the mechanisms of breakage, folding , smearing and impacting.Grinding kinetics were characterized at laboratory scale with breakage and selection functions. The breakage function showed that 75% of gold disappearing from the 840 µm to 1200 µm class reported to the 600 µm to 840 µm; this figure is much higher than for silica (46%) or most other minerals, and implies that comparatively fewer fine fragments are produced from the breakage of gold flakes, on account of gold's malleability. The selection function of silica was four times that of gold. At plant scale, the ratio of the selection function of ore and gold increased from 6 for at 50 urn to JOO pm to 20 at 500 um to 1000µm.Observation of original flakes and their fragments with the scanning electron microscope showed that the main mechanism of ""grinding"" from the 840 µm to 1200 µm to the 600 µm to 840 µm class was folding rather than actual breakage. This was confirmed by a measure of individual flake weight. The postulated breakage cycle is that relatively globular flakes become increasingly serrated through grinding; they can then regain their original shape through folding and reflattening into cylindrical and spherical shapes, as the majority does; however, some fragments will at this point undergo actual breakage. Photograhic evidence is presented to support the proposed mechanisms.Smearing of gold unto silica was observed when silica was ground after a gold, and embedding of silica into gold flakes when gold was ground after a silica. Both mechanisms occur whenever gold and harder minerals are jointly ground, and result in ""unliberation"" of gold. It is postulated that smearing of gold onto other minerals plays an important role in explaining how gravity recovery can increase over-all gold metallurgy, especially when used ahead of flotation.Classification of gold in the primary hydro cyclones takes place at a much finer cut-size than ore, 20 µm vs 57 µm. This and the slower grinding kinetics result in high gold circulating loads in the primary loop, 6700%, and a gold content in the primary cyclone underflow (PCUF) is twenty-four times that of the ore. The gold size distribution for primary cyclone overflow is much finer than that of the ore, although they are essentially similar in the PCUF.Liberation, or more accurately ""gravity recoverability"", was assessed with a 7.5 cm (3 in.) Knelson concentrator. It varied between the thirties for the primary mill discharge and two cyclone overflows, to highs of 89% and 92% for the PCUF and secondary mill discharge."

Jan 1, 1991

By M. Kawata, T. Amano, T. Miyamoto, K. Shibayama

"The High Pressure Acid Leach (HPAL) plant of Taganito HPAL Nickel Corporation (THPAL), located in Taganito, Philippines, with a nameplate capacity of 30,000 Ni-t/year started commercial operation on October 2013. The plant load was smoothly ramped up and it achieved monthly production equivalent to 33,000 Ni-t/year in 2016. Partial improvement of the plant capacity for the achievement of 36,000 Ni-t/year, as evaluated from the current operation progress of each system is planned for 2017. In this paper, aside from presenting the progress of the plant ramp-up, research and development activities such as the reduction of nickel loss and the improvement of filtration capacity which was achieved by particle size control of ZnS precipitates in the Zinc Removal system are also discussed.INTRODUCTION Taganito HPAL Plant Project History of THPAL Taganito HPAL Nickel Corporation (THPAL) was incorporated in August 2008, as a joint venture of three (3) companies, namely Mitsui Corporation with 15% share, Nickel Asia Corporation (NAC) with 10% share and Sumitomo Metal Mining Corporation (SMM) with a controlling stake of 75%. Aside from its capital share, NAC’s Taganito Mining Corporation (TMC) supplies the ore for the HPAL plant located in Taganito, Claver, Mindanao, Philippines. The objective of THPAL is to produce 30,000 MT of nickel and 2,600 MT of cobalt as mixed (Ni/Co) sulfide by treating nickel laterite ore in the Philippines and exporting to Japan as raw material for SMM’s Niihama Nickel Refinery (NNR) for the next 30 years. In other words, 1.15 wt% of nickel in ore is refined to 99.99 wt% nickel in electrolytic nickel. The mixed (Ni/Co) sulfide is shipped to NNR and SMM provides the technology and management personnel to THPAL plant as well as sulfuric acid which is the main reagent for HPAL process. Figure 1 shows the location of THPAL and current relationship between the stake holders.The Characteristics of THPAL Plant In terms of plant design, a 2-train system is applied for the HPAL circuit considering the reliability of the process, facility and avoidance of whole plant shutdown due to HPAL troubles. The technical data, operation know-how and improvements gained from the successful operation of Coral Bay Nickel Corporation (CBNC) which was established in April 2002 were reflected in THPAL’s plant design. As for the H2S plant, a more economical design was considered which is different from CBNC."

Jan 1, 2017

By T. Gerritsen, R. MacRosty, R. Pula

For several years Hatch has been installing fibre optic temperature sensors on the copper cooling elements of smelting furnaces to improve monitoring capabilities in critical locations. The metal/matte tapblock is a key area to monitor in the furnace as it undergoes severe wear from the molten material repeatedly drained through it. The high wear rate around the tapblock means downtime is necessary to perform refractory repairs. A good understanding of the tapblock condition allows the operation to maximize safety and production; consequently the metal/matte tapblocks have been the focus of this study. Fibre optic technology allows the installation of numerous sensors in locations that are very sensitive to refractory thickness, thereby providing information previously unavailable with traditional measurements. The transient nature of the thermal response to tapping and the three-dimensional geometry of the tapblock confound the interpretation of refractory thickness from temperature measurements. This paper focuses on the analysis of both plant data and thermal modelling simulations and details the progress made in relating the temperature measurements to the refractory thickness in front of the copper tapblock.

Jan 1, 2014

By Jose R. Hernandez-Aguilar

"This paper revisits data from previous studies (Hernandez-Aguilar, 2010, 2011) to better understand the link between metallurgical performance and bubble size (Db) in the collection (pulp) zone of full-scale flotation systems. To obtain conclusive evidence exclusively related to the collection zone, the experiments were designed in those studies to control both the bubble generation method and the influence of the froth zone on the overall metallurgical performance in industrial and pilot-scale flotation columns. The results showed that generating small (1 mm) bubbles had a significantly higher beneficial effect on the recovery of coarse (> 75 µm) particles compared to the effect on fine (< 16 µm) particles. It was observed that, under certain practical conditions, the recovery of liberated coarse particles was close to zero, but could be recovered almost completely by reducing bubble size. The evidence revealed an apparent inconsistency of the so-called “k–PSb” model: at constant froth recovery, increasing Sb did not always result in higher recovery, as the model predicts. Overall, the evidence showed that it was not the Sb but the bubble size that proved to be a more reliable link to metallurgical performance. Only under highly suboptimal bubble size conditions (Db = 3 mm) did the froth zone seem to play a role, possibly reflecting an effect of pulp-zone bubble size on froth stability. However, for the most part, both the bubble generation method and the froth zone played inconsequential roles. An empirical model that better describes the kinetics of particle collection is proposed.INTRODUCTIONStudies showing the link between metallurgical performance and the interactions of bubbles and particles in the collection (pulp) zone of industrial flotation systems are scarce. A common belief among a number of mineral processing practitioners considers that “small” bubbles are favourable to recover “small” particles and that, conversely, “larger” bubbles are more efficient at floating “coarse” particles. However, perceptions like this are often substantiated by anecdotal evidence rather than by rigorous data analysis. What is the optimum bubble size for a particular case, how operating conditions can be adjusted to control a target bubble size, and whether the bubble size needs to be changed in the first place to optimize the operation of a flotation plant are questions that usually remain without solid answers.The studies reported by Hernandez-Aguilar (2010, 2011) were, in part, performed to test the effect of bubble size on flotation response and, thus, help address some of the above questions. The focus of the studies was to optimize the metallurgical grade-recovery performance of the Cu-Mo separation plant at Teck’s Highland Valley Copper mine (HVC). The outcome was compelling and significantly valuable: consolidated production data showed that in 2008 – the year when the recommendations from the studies started to be implemented – the Mo plant recovery was 89%, and gradually increased to 92% and 94% in 2009 and 2010, respectively, along with an increase in Mo concentrate grade. (Note: these production figures were not included in the publications quoted above; however, they were shown during an oral presentation at the 43rd Annual Meeting of the Canadian Mineral Processors in 2011.)"

Jan 1, 2016

By Peter J. Franklin

"Short-term mine planning of open pits is an activity that has historically been carried out by hand. Typically, the use of computers has played little part in this type of mine planning. This paper describes the objectives and the procedures involved in short-term mine planning, comments on the type of computer systems available, and describes in detail a computer-aided short-term planning and scheduling system known as STEPS.IntroductionThe mine planning department of any o pen-pit mining operation performs a wide variety of different tasks. However, their primary concern is the preparation of detailed long-and short-term mine plans. These mine plan s will define the long-term operating strategies and definitive everyday working plan s for the ongoing development of the open pit.In this day and age, when operating costs have spiralled upwards due to inflation , and product revenues have decreased due to depressed economies and poor markets, it is vitally important for all aspects of the mining operation, including mine planning, to be efficient and cost effective.There are numerous options available for planning engineers when generating a mine plan. A cost effective mine plan must investigate all these options and select the optimum. When using manual planning techniques, it is often impossible to evaluate all the available options. To do this, and to produce an optimum mine plan, a computer is required.This paper discusses mine planning, with emphasis toward the short-term plan and comments on how the processes may be computerized. It also describes in detail, a computer software system called STEPS, which has been designed as an interactive graphics, computer-aided short -term mine planning and scheduling tool."

Jan 1, 1985

By Mehmet F. Taner

"The East Sullivan Stock (ESS) is a small, composite felsic alkaline pluton of presumedlate Archean age in the Val d’Or mining district. Three main facies have been distinguished: mon-zonite sensu stricto, porphyritic monzonite, and green trachytic porphyry. This monzonitic group ofrocks is of relatively homogeneous composition with high abundances of Na2O, K2O, Ba, Sr, Rb, Zr,Mo and LREE. The alkaline ESS is distinguished from other igneous units in the Val d’Or miningdistrict, such as the Bourlamaque Batholith, by relatively high concentrations of Ba, Sr, Rb, Mo, Cuand Au. The ESS hosts many base (Cu, Mo) and precious (Au) metal occurrences, including: (1)porphyry style Cu-Au-Mo disseminated sulfde deposits, (2) Cu-Au deposits in volcanic rocks near the ESS contact, and (3) pyritic gold mineralization in east-west trending shear zones. The ESS is well defined by concentrical zoning on the aeromagnetic vertical gradient color map, and displays four linear trends, which are assumed to be structural lineaments, at 035°-055°, 320°-300°, east-west, and north-south. The main mineral occurrences related to the stock display a preferred spatial association with the east-west linear magnetic trends.The ESS is preferentially located along a major structure and was emplaced late in the evolutionof the Abitibi subprovince like other felsic alkaline plutons. This stock is similar to late-tectonic min-eralized felsic alkaline intrusions of the Kirkland Lake and Larder Lake mining districts in Ontario, and to the Allard stock in the U.S.A. which is associated with gold and base metal mineralization. Similarities also exist with younger alkaline plutons associated with Cu-Mo-Au porphyry deposits in the Canadian Cordillera, which formed in tensional tectonic environments. The felsic alkaline magmamay have formed by partial melting of deeply buried supracrustal rocks, concomitant with the development of deep fractures such as the Cadillac Fault. In such an environment, hydrothermal solutions carrying remobilized metals from deep supracrustal rocks may have deposited gold and base metals in structural traps. Plutons similar to the ESS should be good targets for mineral exploration. Copyright © 1996 Canadian Institute of Mining, Metallurgy and Petroleum."

Jan 1, 1996

By D. A. MacFadyen, J. J. Brummer, C. C. Pegg

"The first record of a kimberlite found in Canada (1946) was the identification of thin dykes intersected while drilling for gold in Michaud Township, Ontario.Sampling of the Munro Esker (1964) in the Kirkland Lake area, Ontario, by the Geological Survey of Canada identified the occurrence of detrital grains of pyrope garnets along a length of 35 km of the 113 km tested. A search for the source of the garnets resulted in the identification (1968) of a narrow subsurface kimberlite dyke in the Upper Canada Mine. This discovery resulted in a staking rush. Unfortunately, subsequent work did not identify the source of the kimberlite indicator minerals.During 1978 the Ontario Geological Survey started a multi-discipline study of 29 townships (2560 krn2) in the Kirkland Lake area, to encourage exploration for gold, base metals, and kimberlites. Back-hoe sampling (1979 to 1982), where the overburden was thin, and reverse circulation drilling, in areas of thicker drift, yielded samples of the till. These were analyzed for several elements and a mineralogical identification of the heavy minerals was completed. Pyrope and chrome diopside grains were identified.Studies of the Pleistocene geology indicated only the most recent direction (167 degrees) of ice advance (Matheson) and the associated deposits, out of a possible three advances known to occur in the general region straddling the Ontario-Quebec boundary, is present in the immediate area of Kirkland Lake. Contouring the distribution of pyrope grains (1990) showed a concentration centered over an area of 616 km2 extending down-ice from Gauthier Township. This included a smaller area containing chrome diopside grains. Kimberlite boulders were identified (1981) in gravel pits on the Munro and Misema River Eskers located within this anomalous area. The next step would be to use the airborne geophysical data to locate the kimberlite pipes which yielded the indicator minerals and boulders. The source area is likely to be in the northern half of the Ontario Geological Survey study area."

Jan 1, 1992

By M. Celikin, M. Isac, R. I. L. Guthrie, S. Ge

Horizontal Single Belt Casting (HSBC) is a near-net-shape casting process in which molten metal is directly cast into thin strips, at high cooling rates (order of several 100°C/s), with the potential for high volume, friction-free, continuous production of metal strips. This casting process was used in the present work to produce strips of Al-Mg alloys in the AA5000 series, with additions of Sc and Zr. Such aluminum alloys show exceptional potential as a structural material for transportation/aerospace applications. To demonstrate the suitability of the HSBC process to manufacture competitive strip products of Al-Mg-Sc-Zr, the mechanical properties and microstructures of the strips produced using the HSBC process were compared with conventionally cast products. The effects of annealing on the mechanical properties of the strip-cast Al-Mg-Sc-Zr alloys were also investigated.

Jan 1, 2014

By Xuanxue Mo, Kaihui Yang, Steven D. Scott

Abstract -The Changning-Menglian metallogenic belt in western Yunnan, China, is characterized by the occurrences of both Pb-Zn-Cu and Cu massive sulfides in Permo-Carboniferous mafic volcanic sequences. These deposits were formed in a back-arc basin at a rifted continental margin in the Paleozoic Tethys Ocean. Pb-Zn-Cu deposits are associated with alkalic basalt, andesite, and lesser felsic volcanic rocks intercalated with limestone, which probably formed along an immature rifting segment on a continental basement. These volcanic rocks are enriched in K, Ti, LREE, and other incompatible elements, and have the attributes of alkalic within-plate basalt. An extensive unit of sulfide- carbonate-silica shale in proximity to massive sulfides contains high values of Mn, As, Mo, W, Sn, Sb, and Hg, and has REE patterns that are similar to the volcanic rocks. This, together with the graded bedding in the footwall volcanic rocks, suggests that the sulfides precipitated in a shallow, unstable, and carbonate-saturated volcanic basin. A stringer zone is traced downward for 500 m below the massive sulfide orebodies. It is characterized by an upper sericite-quartz zone and an extensive lower skarn alteration with enhanced W, Sn, and Bi. Lead isotope data show both continental basement and magmatic sources may have supplied the ore metals. Cu deposit and occurrences are hosted by tholeiitic units that represent the mature spreading segments in the back-arc basin. The tholeiitic lavas have LREE-depleted or flat REE patterns similar to MORB or back-arc mafic lavas. The cupriferous massive sulfides are overlain by an extensive unit of chlorite-magnetite or ochre, suggesting a relatively oxygenated oceanic basin. Ni and less Co mineralization is found in dolomite veins of the stringer zone. Enhanced concentrations of Ni, Co, Au, and As are found in the massive sulfides and in sulfide-rich tuffites. The geological setting and mineralization of the Changning-Menglian belt has similarities with modern back-arc basins such as the Manus Basin in the western Pacific.

Jan 1, 1999

By T. J. Bruce, G. E. Agar, R. Stratton-Crawley

"A technique by which the design of a flotation circuit may be optimized is described and examples of the application of this methodology are given.Three interrelated criteria are defined and the application of these criteria to the selection of the optimum residence time for each stage of a flotation circuit is demonstrated. The criteria are:(1) Add no material to the concentrate that is lower in grade than the feed to that separation stage.(2) Maximize the difference in recovery between the desired mineral and the gangue.(3) Maximize the separation efficiency.Three independent systems were examined experimentally and it was shown that application of any of the criteria yielded similar results.It was demonstrated how the application of rate measurements (Criterion #2) could lead to the selection of a set of optimized times for several stages in a flotation circuit and that these could in turn be used to simulate the results of a locked cycle test. The predictions were checked against the experimental results from a locked cycle test and there was substantial agreement between the predicted and observed results."

Jan 1, 1980

By Larry G. Twidwell, Corby G. Anderson, Camille M. Fleuriault

"The selective precipitation of iron as ammonium jarosite is a well-established industrial technology in base metals hydrometallurgy. It is a key technology in minimizing iron tenors which would be disruptive to downstream processing. It also provides a more readily filterable iron solid to better facilitate materials handling. This paper elucidates the fundamentals behind industrial iron precipitation. Then, the details of the successful optimization of an industrial ammonium jarosite circuit are presented.HYDROMETALLURGICAL IRON REMOVAL FUNDAMENTALS Iron is the fourth most abundant element in the Earth’s crust (5% by weight) and is often found in complex ores such as sulphide-bearing formations. Iron represents an issue though during leaching, a technology which is widely used for the treatment of this type of ore: •,Iron has the particularity of forming hydroxides when leached under certain conditions. Iron hydroxides form a viscous gel, which is difficult to filter and traps valuable elements such as silver. •,Iron is solubilized along with other metals and interferes with the subsequent extraction steps. As a result, purification of the pregnant leach solutions is required to achieve economical extraction of base metals. In the 1960s, metallurgists developed iron precipitation processes for solution purification (Habashi, 1999). Nowadays, precipitation of iron bearing species, such as goethite, hematite or jarosite, has become one of the most common methods used in the industry to purify leach liquors. To be suitable, the precipitate has to be readily filterable and thus must not be too fine of particle size. Precipitation can take place in autoclaves at medium to high temperatures, under an oxygen or air overpressure (Tourre, 1984, Fleuriault 2016, Fleuriault Anderson Shuey, 2016))."

Jan 1, 2016

By Mark B. Thorpe

Golden Star Resources started gold mining operations in Africa in 1999 after 15 years of exploration in South America. At the time, the approach to local assistance was through "alternative livelihood" programs and the donation of infrastructure to local communities. This was initially successful with local community support. However, with time and on reviewing the implemented projects, it became evident that the success was limited and many if the projects were either poorly used or in disrepair. Through a review of the options, we decided to develop a community assistance model driven by the communities themselves, while keeping control of the finances and the actual construction of the projects. Through the formation of the Golden Star Development Foundation, we began to support community driven projects for local economic development. The evolution of economic development projects continued over the next several years with the addition of project requirements for partnerships with government, and finally an evolution to a partnered turn-key piece of infrastructure that we hand over to an agency for operation and ongoing maintenance. We are currently working with outside partners to further our economic development activities in Ghana to the benefit of our stakeholders.

May 1, 2011

By R. I. Grauch, Michael D. Glascock, Chen Nansheng, Jr Coveney, James B. Murowchick

"Unusually rich molybdenum ores (cutoff grade = 4.10/0 Mo) hosted by Lower Cambrian black shales have been mined since 1985 near Zunyi in the province of Guizhou in China. Similar ores were once worked for Mo and Ni near Dayong in the province of Hunan. In both mining areas, mineralization occurs in Lower Cambrian black shale (Niutitang Formation and stratigraphic equivalents) as a single sulfide bed or lens with exposed thicknesses up to 15 cm and reported thicknesses up to 35 cm. In addition to high Mo values (4% to 7%), ore samples contain up to 7% Ni, 2% Zn, 2.5% As, and several hundred ppb Au and Pt-group elements, but the precious metals have never been recovered from the ores. Sporadic occurrences of Mo-Ni sulfide ore beds are found in at least five provinces stretching approximately 1600 Ian from Yunnan to Zhejiang. None of the Mo-Ni ore-bed occurrences has any obvious connection with mafic or ultramafic source rocks. Similar occurrences containing elevated values for Ni, Mo, and PGE exist in Devonian black shale in the Yukon. Future exploration for Pt, Au, Mo, and Ni deposits should consider this previously unknown type of sediment-hosted mineral deposit.Sommaire - Des minerais anormalement riches en molybdène (teneur-limite = 4.1% Mo) provenant de schistes argileux noirs du Cambrien Inferieur ont été exploites depuis 1985 près de Zunyi dans la province de Guizhou en Chine. Des minerais semblables ont déjà été traire pour Mo et Ni près de Dayong dans la province de Hunan. Dans ces deux régions minières, la minéralisation se présente dans le schiste argileux noir du Cambrien Inferieur (Formation Niutitang et équivalents stratigraphiques) sous forme de couche ou lentille unique de sulfures avec des épaisseurs exposées de plus de 15 cm et des épaisseurs rapport6es de plus de 35 cm. En plus des fortes teneurs en Mo (4%-7%), des échantillons du minerai contiennent jusqu’ à 7% de Ni, 2% de Zn, 2.5% d&apos;As, et plusieurs centaines de ppb d&apos;or et d&apos;éléments du groupe du platine; toutefois, les métaux précieux n&apos;ont jamais été récupérés des minerais. Des présences sporadiques sous forme de couches de minerai sulfure de Mo-Ni se retrouvent dans pas moins de cinq provinces s&apos;etendant sur 1600 km de Yunnan a Zhijiang. Aucune de ces présences de minerais, sous forme de couches, ne semble associée a des roches du type mafique ou ultramafique. Des présences similaires contenant des teneurs élevées en Ni, Mo et EOP se retrouvent dans le schiste argileux noir Devonien du Yukon. L&apos;exploration future pour des gisements de Pt, Au, Mo et Ni doit prendre en considération ce type de gisement encore inconnu précédemment."

Jan 1, 1992

By M. C. Ethier, A. L. Laramie

"The Granisle and Bell Copper mines were officially put into production in 1966 and 1972, respectively. The Granisle Mine was purchased in late 1979by Noranda and the two operations were amalgamated as one division. Both mines were closed in 1982after sustaining heavy financial losses during a period of low copper prices beginning in 1981.This paper describes the resumption of operations at the Bell Mine in 1985 after its shutdown period of three years and the dramatic and sustained improvements in productivity and efficiency realized as a result of a commitment by employees and management to the application of Participative Management and Employee Involvement principles. After a general description of the effects of such a philosophy on the operation as a whole, and a comparison to the operation&apos;s last full year as a producer, it deals with the practice of this philosophy in the maintenance department at the Bell Mine and the superb results realized.IntroductionThe Bell Copper deposit was discovered in 1963 and came onstream as a 10000 ton s per day open pit mine in the fall of 1972. Identified reserves at that time were 46 million tons of ore containing 0.50% copper. The mine shared facilities of the townsite of Granisle with the nearby Zapata-Granby mine which had established the community six years earlier.Because of easy grinding ore and improvements to milling circuits, Bell&apos;s throughput rate was increased to 17 000 tons per day by the late 1970s. In the open pit, improvements resulted in mining of additional reserves with higher stripping ratios. At startup, a half ton o f waste was mined for every ton of ore processed.By the end of 1982, with 48.2 million tons already mined, the Bell Mine had identified additional mineable reserves of 39.4 million tons containing 0.52% Cu.In November 1979 the Granisle Mine was purchased from Zapata-Granby. The two mines, with a total of 700 employees, were operated under common management as the Babine Division until 1982 when low copper price s forced the closure of both for an indefinite period.The outlook for copper prices remained bleak and only 50 people were retained on the payroll to maintain the two plants, most of them working on a part-time schedule.The population of the Village of Granisle dwindled from over 1500 inhabitants to under 500, as people moved away to seek other employment.Prior to the shutdown, the Bell Mine employed 370 people and pit extraction averaged nearly 50000 tons per day of which 16000 tons was mill feed, and the remainder waste. Total cost to produce a pound of copper was C$1.36 in 1982."

Jan 1, 1990

By Carol Odell

This paper was prepared as a brief for Prospectors and Developers Association of Canada (PDAC) to guide input at a series of round tables carried out by the Federal Government in response to the 38th Standing Committee on Foreign Affairs and International Trade (SCFAIT) report, on ?Mining in Developing Countries and Corporate Social Responsibility?. This document mandate is to provide background information, analysis and recommendations on the practice of Canadian exploration and mining companies abroad. This research was based on 11 case studies of Canadian companies which have experienced conflicts or controversies overseas. All case studies were assembled through an extensive literature review of publicly available documentation and communications with representatives of the mining companies to assist in deepening the insights into the drivers of the conflicts and the needs of Canadian companies in similar situations. The case studies include both exploration and mining operations. Our analysis begins with the identification of general and case specific drivers of conflict/controversy in each case study. Company names are kept confidential and only anonymous results are presented. We make ample use of simple flow charts and schematic diagrams to explain how contextual drivers and aggravators and company drivers and mitigators play varied and interrelated roles in conflicts. The diagrams also illustrate the cumulative analysis of drivers including the linkages among drivers/aggravators/mitigators across different domains (social, governance, NGO/media and company). Finally, we discuss needs of companies and propose recommendations for addressing social responsibility and human rights concerns.

May 1, 2007