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By C. Juers

Laboratory chromate coating was applied on AM50 and AZ91D alloys and compared to phosphate-permanganate one. Evaluation of the corrosion behaviour was performed using electrochemical DC and AC methods in ASTM water D1384-87. This electrolyte was chosen because it was moderately aggressive and found to give generally good correlations with long period exposure results in atmospheric conditions. Electrochemical impedance spectroscopy was used to determine more accurately the corrosion rates from the analyses of the high frequency capacitive loop. Anodic polarization was applied in order to evaluate the pitting resistance of the different coatings. These results were correlated with weight loss data evaluated from experiments performed by immersion tests in ASTM water D1384-87 and climatic cyclic chamber tests.

Jan 1, 2006

By S. Flewelling, M. Scobie, G. R. Baiden

"SynopsisA feasibility study to develop a research program, the Mine Automation Plan (MAP), was recently completed. This was undertaken by a team comprised of Inco Ltd., Falconbridge Limited, the Canadian Centre for Automation and Robotics in Mining (CCARM) and the Centre for Resource Studies (CRS). The study was sponsored by PRECARN Associates, which is a consortium of thirty-six Canadian companies focussed on research and development in artificial intelligence and robotics. PRECARN Associates was formed in 1987 when a number of research proposals were funded in the fields of process control systems, robotics systems and intelligent engineering systems. In July 1991, PRECARN accepted the next round of proposals for research. The MAP project was one of the successful proposals, being awarded $100,000 for the development of a feasibility study defining a long-term R&D plan for underground hardrock mining automation.The development of the feasibility study started by addressing the fundamental structure of the mining process, and its relationship to the metallurgical process, over-all infrastructure support and management systems (Fig. I).Mining may be considered as comprising five subprocesses: (I) delineation; (2) development; (3) production; (4) backfilling; and (5) infrastructure support services. Within these subprocesses many applications for artificial intelligence and robotics exist. The mining process is dependent upon the interaction between the physical mining process and information. For example, the delineation process is dependent on geomechanical, geochemical and geophysical techniques to develop a model of the orebody based upon access to such data. This same relationship between the physical and information models holds true through the development, production, backfill and infrastructure support systems.The foundation for the MAP study has been the recent development by Inco Ltd. of an underground communications system (Fig. 2). The system has the ability to supply high bandwidth communications, over voice, data and video to mobile and stationary locations within the mining operation. It is seen to be the future backbone of a comprehensive, automated information system which should permit the application of the concept of Computer Integrated Manufacturing (CIM) to underground mining. CIM, through the automated flow of information, has been successful in integrating the engineering, production and various support groups in manufacturing."

Jan 1, 1994

By E. H. Dudgeon

In order to make increased use of automation in copper smelting, it is evident that a useful first step .world be the accurate determination of the copper end point in the converter operation. After laboratory tests, the copper end points in a copper converter at Gaspe Copper Mmes Ltd. were determined without reference to melt samples or other observations. The results indicated that the rapid measurement of the S02 level in the gas released from the converter has potential as a new and independent method of determining the copper end point in converter operation.

Jan 1, 1966

By Peter Cunningham

Teck Facts and Figures ? Employ more than 14,000 around the world, includes: ? Over 8,600 in Canada (close to 7,800 in British Columbia) ? Close to 2,000 in Chile ? Over 2,700 in Peru ? Approximately 600 in U.S. ? Hundreds more in exploration around the world ? Total capital expenditures ? $1.8 billion for 2012

Aug 1, 2013

By L. Tikasz

The primary purpose of ore hauling model studies is to capture the variability of the ore delivery ? stockpiling process in order to improve the estimation of equipment capacities and achievable throughputs. The operation of a mine-to-site ore delivery system is the subject of a number of challenges. Typically, ore is hauled by a given combination of trucks, conveyors and trains. In addition, ore loading, ore transferring to another means of delivery, stockpiling, reclaiming, and further deliveries involve many other types of equipment. The concurrent operation of all these units is scheduled; nevertheless, they are subject to planned maintenance and random breakdowns. To support our engineering design work on ore hauling operation, discrete event type models were built for each specific task. Then, due to recurring demands, an ore hauling library was gradually compiled. The now available model library allows fast and efficient simulation of various mine-to-site hauling arrangement, adaptable to various mining and mine construction operations (e.g. bauxite, iron ore, copper ore and coal).

Aug 1, 2013

By W. G. Brissenden

"ALTHOUGH I SHOULD FIRST REVIEW the state of the mining art as it is today, because of the shortness of time I will confine myself to a re-view of the more important advances in that art which have been made in the past two to three decades. Then, a look at the opportunities and the challenges which now present themselves will be more meaningfulFirst, some of the more impor-tant developments in underground mining:(1) The recognition that good ventilation, visibility and working conditions are essential preliminaries to efficient production has resulted in their incorporation as a matter of practice in modern mine planning. (2) The introduction of the car-bide bit and the re-introduction of the airleg drill, and the resulting sharp rise in productivity, were early postwar developments. (3) The recovery of the coarser fraction of mill tailings for use as mine backfill also is an important cost-reducing development of recent years -and this has led to cemented backfill, which, al-though more expensive, meets certain specific needs and has tremendous potential. (4) Great strides have been made in improving explosives' materials and explosives' accessories. Millisecond-delay electric blasting caps, which improve fragmentation and reduce the seismic effect of blasting, and the development and •application for underground use of explosives are but two among many such improvements. (5) Trackless mining methods, using quarry-type equipment in some instances and specially de-signed low-headroom trucks, loaders and carrier-mounted drills in others have been successfully applied. (6) Dual-purpose load-haul units are now in use loading and hauling from open stope drawpoints, and smaller versions of this type of unit are in use in cut-and-fill and other types of stopes."

Jan 1, 1968

By Vicki Tschirhart, Bill Morris, McMaster University

A new method for mapping faults within basement rocks underlying the Thelon Formation and glacial overburden was developed and tested in the Aberdeen Sub-basin. This method utilizes newly acquired aeromagnetic data, the Blakely algorithm for defining magnetic source edges, a calculated dip-direction map, a digital elevation model (DEM) derived from the Canadian Digital Elevation Database, and the positions of identified, inferred and newly mapped faults that are within and adjacent to this sub-basin. Combining these data revealed three age groups of faults. One group is seen only on the DEM; these faults are young brittle structures that have no effect on the sub-Thelon basement unconformity, and are not visible on the dip direction map. A second group is evident on the dip direction map but not the DEM; these faults are old basement structures that did not propagate upward through the Thelon Formation. The third group is expressed on both the DEM and dip direction map; these faults are also old structures that propagated upward during and/or after deposition of the Thelon Formation. The latter group of faults may be of greatest interest for uranium exploration, with reactivation increasing their potential to serve as conduits to transport uranium-rich fluids and focus deposition at or near the unconformity surface. This methodology has promise for comprehensive mapping of basin faults and tracking the tectonic development of the whole Thelon Basin through time.

Jan 1, 2013

By Frank Otten, Jochen Greinacher

"In July 2017, Deilmann-Haniel signed a contract with IOO Slavkaliy to sink two 750 metre (m) deep freeze shafts for the Nezhinsky Potash mine in Belarus. This is the second shaft project where this technology is employed after two over 1,000 m deep shafts for a potash project in Saskatchewan, Canada, have been sunk by the application of the Herrenknecht Shaft Boring Roadheader (SBR) technology. Developed to sink shafts for green field projects in soft to medium hard rock, in frozen or unfrozen geology, the machine technology utilizes a roadheader-type cutterhead on a telescopic boom to mechanically excavate the rock, and a pneumatic mucking system to convey the muck from the face into the buckets. This leads to a manless face during the sinking cycle and thus a significant improvement in terms of workplace safety. For the Nezhinsky project, the SBR design was significantly modified in close cooperation between Deilmann-Haniel and Herrenknecht, based on the available experience and the special requirements of the project. Such modifications have been for example the adaptation of the Pneumatic Mucking System to cope with wet material as well as dry as originally planned or the shaft lining moving from shotcrete application to jump for and tubbing installation for which a step-change hands-off tubbing erector for the placement of segments was designed. Further modifications to optimize the machine technology for the requirements during shaft sinking were applied on the two machines for the Slavkaliy project as well as several revisions to match the special project requirements. The SBR is suitable for soft and medium hard rock up to 100 MPa UCS. The main design limits are maximum weight of the machine with 400 tonnes and length or height of 50 m due to the depth of the pre-sink. The Pneumatic Mucking System was changed in all components, sheaves and rope arrangement were redesigned and the concept of the hoist system was also re-engineered. The SBR in Belarus is configured for a daily sinking rate of three metres and all systems behind the cutting boom are not the bottle neck of the whole system. The works on site started in November 2017 including freeze hole drilling, construction works, site setup, installation of hoists winches, permanent headgears and other components required for sinking. The SBRs arrived on site in June/July 2018 and were preassembled on surface and then lowered into the 50 m pre-sink. SBR #1 started full face sinking in mid-December 2018, and SBR #2 in late January 2019. By the end of February 2019, the machines were at 150 m and 100 m depth respectively, and achieved up to 3.6 m/day concrete lined shaft. The SBR and the sinking system, the experiences, problems, technical solutions and performances of this challenging project will be presented in this paper."

Jan 1, 2019

By J. P. Caulfield

THE Hudson Bay Mining and Smelting Company's underground mine at Flin Flon, Manitoba, has in the past been serviced by two working shafts-the North Main shaft, and the No. 3 shaft. The North Main shaft is used to hoist the total production from under-ground, and handles the greater part of the mine supplies and crews. The shaft is five-compartment design, rectangular in cross-section, and is equipped entirely with steel shaft sets from the surface to the finished depth of 2,210 feet. Hoisting equipment in the surface plant will not permit the North Main shaft to be extended below its present finished depth. The No. 3 shaft, located approximately 2,300 feet from the North Main shaft, is used primarily as a ventilation shaft, and for hoisting lower-level development waste to the 390 level, where this material is used as mine fill. The No. 3 shaft is of standard rectangular design, timbered with 8-in. by 8-in. creosoted fir sets, hung on 6-foot centres. From the surface to the 1,430 level, the No. 3 shaft consists of three 5 ft. by 5 ft. compartments, and below this level to the completed depth of 2,300 feet, the shaft is increased to four compartments. To service the mine and to expedite development below the 2,210 level, a one and one-half compartment winze was sunk from the 2,210 level to a depth of 766 feet, or approxima tel y the 3,000 level.

Jan 1, 1941

By M. J. Michaud, M. J. Lavigne

"Abstract - North American Palladium Ltd. operates its Lac des Iles open pit palladium mine 85 km north of the city of Thunder Bay, Ontario. The Roby Zone deposit occurs within the mafic/ultramafic Lac des Iles Intrusive Complex (LDI-IC), which was created by multiple pulses of magma of varying composition within several closely spaced chambers. Chaotic lithological distribution, the presence of magmatic breccias, and the rarity of rhythmic layering suggest a dynamic intrusive environment with disruptive magma pulses. As of December 31, 2001, measured and indicated resources for the 950 m long by 815 m wide Roby Zone deposit totalled 159 Mt grading 1.55 g/t Pd, 0.17 g/t Pt, 0.12 g/t Au, 0.05% Cu, and 0.05% Ni at a palladium cut-off grade of 0.7 g/t. The Roby Zone contains an additional 73 Mt of inferred resources at similar grades.The Roby Zone is dominated by varitextured gabbro containing pipes and pods of breccia, and large blocks (~60 m across) of varying lithology. Mineralization at Lac des Iles occurs as: (1) a PGEand base metal-rich magmatic matrix of breccia (breccia ore); (2) mineralized dikes or sills (gabbronorite in North Roby ore); (3) lower-grade mineralization in varitextured units that are host to the distinctive breccia ore and envelope the North Roby ore; and (4) high-grade mineralization associated with strong silicate alteration exemplified by high-grade ore.The close spatial association of the mineralized breccias with both varitextured units and silicate alteration leads to an interpretation that the energetic magma that created breccia was charged with a dissolved fluid, and that this deuteric fluid exsolved at high temperatures to migrate through crystal mush, enhancing crystallization along its pathways, resulting in variable grain size. This transformation occurred at high temperature and produced sulfide-poor, varitextured gabbro-hosted mineralization exemplified by some of the mineralization in the North Roby Zone, and also found throughout the Roby Zone. The association of hydrous silicate alteration with mineralization can be explained by continuing fluid migration during cooling and continued metal transport. Résumé - North American Palladium Ltd. opère la mine à ciel ouvert de Lac des Iles située à 85 km au nord de Thunder Bay, Ontario. Le gisement Roby Zone est encaissé dans le complexe mafique/ultramafique de Lac des Iles (LDI-IC), lequel représente une intrusion polyphasée créée par plusieurs pulses magmatiques de différente composition à l’intérieur de chambres magmatiques fermés. La distribution chaotique des lithologies, la présence de brèches magmatiques, et la quasi-absence de litage rythmique suggèrent un environnement magmatique dynamique perturbé par l’introduction de nouveau magma. Au 31 décembre 2001, les ressources mesurées et indiquées s’élevaient à 159 millions de tonnes titrant 1,55 g/t Pd, 0,17 g/t Pt, 0,12 g/t Au, 0,05% Cu, et 0,05% Ni, pour une teneur de coupure de 0,7 g/t Pd. De plus, la Roby Zone contient 73 millions de tonnes de ressources inférées à une teneur similaire.La Roby Zone est principalement encaissée dans un gabbro de texture hétérogène (varitextured) caractérisé par des cheminées et des lentilles de brèches et des énormes blocs (environ 60 m de diamètre) de plusieurs lithologies. Au Lac des Iles, la minéralisation en EGP et en métaux de base se retrouve dans la matrice magmatique de brèches (breccia ore), dans des dykes ou des sills minéralisés (gabbronorite dans la zone North Roby ore), comme minerai de basse teneur encaissant le minerai de brèche (breccia ore) et enveloppant la zone North Roby. Du minerai de haute teneur est également associé avec une forte altération en silicates dans la zone high-grade ore.L’étroite association spatiale entre les brèches minéralisées et les unités de texture variée (varitextured) et l’altération en silicate suggère que le magma énergique qui a causé la bréchification était chargé de fluides. Ces fluides deutérique"

Jan 1, 2001

By L. M. Pidgeon

Introduction The production of magnesium by direct reduction of the oxide has far passed the experimental stage and was responsible for 30 per cent of the recent wartime production of 246,000 tons per annum. This paper describes the small-scale experiments which culminated in a number of the wartime plants. The paper traces the author's early experiments on various direct reduction reactions leading to his choice of the ferrosilicon reduction of dolomite and the realization that this reaction would proceed at a satisfactory rate at temperatures obtainable in metal apparatus. MgO has a standard heat of formation of 146,100 cal. and is therefore one of the most difficult oxides to reduce. However, if advantage is taken of the relative volatility of magnesium metal, thermally unfavourable reactions may be utilized. In reaction MgO + X = XO+ Mg . . . . . . . . . . . . . (1) the removal of Mg as a gas at high temperatures displaces the equilibrium to the right in the face of the unfavourable thermo-chemistry which is inevitable with any X other than calcium metal. If X is carbon, not only is the reaction highly endothermic, but CO is gaseous. A temperature of l,864°C. is required to produce a pressure of one atmosphere of Mg. Between l,900°C. and perhaps 400°C., the back reaction takes place readily and special shock cooling devices are required to recover magnesium from the gaseous mixture. This reaction does not lend itself to small-scale experiments and was not examined by the author. If, in reaction, carbon is replaced by a relatively pan-volatile metal, the oxide of which is also non-volatile and possesses a fairly high heat of formation, a reduction reaction is offered which is free from the difficulties associated with carbon. The typical case of silicon will serve as an example: 2MgO + Si = SiO2 + 2Mg (g) . . . . . . . . . . . . . . . . . . . . . . (2) At temperatures above l,000°C., a positive pressure of magnesium will exist over the system. Removal of the magnesium vapour will displace the reaction to the right in the face .of an unfavourable thermal balance. Since magnesium is the only volatile component at this temperature, it may be evolved and condensed, using attractively simple distillation technique.

Jan 1, 1946

By John C. McKay

"The five papers which follow, under the heading of ""Technology Transfer-Universities to Industry"", were originally presented at the 20th Annual CIM Conference of Metallurgists in Hamilton, Ontario. They are a unique group of papers, unique because each paper is concerned with applied research done wholly or partly in a university environment and then translated into industrial practice.Universities can rightly be regarded as one of our nation's greatest resources-a veritable storehouse of knowledge and expertise. Yet, too often, this resource is overlooked or, at best, sparingly used by Canadian industry. Of course, university-based research cannot supplant industry-based research, nor vice versa; each type of research activity has its proper role in the over-all process of technology development.University-based scientists are best equipped to conceptualize, innovate, determine viability of basic premises and to verify these at the bench or small pilot-plant level. Industry based scientists are best equipped to develop ""bench-scale"" innovations into mature manufacturing practices. Thus, university-based scientists and industry-based scientists do not compete with, but rather complement, each other. Active, relevant university research enhances industrial research provided good communication between the two ""solitudes"" is continually nurtured.Good communication between industry and university is a prime objective of CSIRA/ACRIS (Canadian Steel Industry Research Association /Association Canadienne pour la Recherches dans d'Industrie Siderurgique), The directors of CSIRA/ACRIS foster improved communication by making regular visits to universities, by sponsoring projects and by providing lists to professors of uncharted areas where basic research is needed. More can be done to improve communication between industry and university, and it is the intent of the Association to do more.The five papers sponsored by CSIRA/ACRIS are examples of good communication and healthy cooperation. It is interesting to note when reading these papers that the cooperation arose, in each instance, as a result of different circumstances. However, there is a common thread and it is personal acquaintanceship-the university scientist/professor and the industry investigator/manager knew each other prior to the initiation of the project."

Jan 1, 1982

By J. Peck, F. Brackebusch, M. Scobie

"A number of alternative strategies exist to improve narrow orebody stope productivity and safety through mechanization. Particular attention is given to one of these: the development of an in-stope mining machine. This paper summarizes those characteristics of vein orebodies in Canadian mines which are considered to govern such mining machine design. It then reviews past and current attempts to develop hardrock mining machines which could potentially be applicable to narrow stope widths.IntroductionSerious interest is mounting to exploit new technology in the development of methods and machinery to stope narrow, hardrock, orebodies. The motives relate not only to the foreseen need to maintain or reduce production costs, but also to considerations of manpower availability, safety, ground control, ore recovery and dilution. This also follows the demonstrated success of technology application in larger metal orebody stoping, where machine development has been seen to lead to improved productivity as well as the future prospects of continuous mining systems and eventual automation, e.g. ITH blasthole drill development and bulk mining. This paper deals in particular with machine design for ore fragmentation in narrow, hardrock orebodies. It is considered that such machine design closely interacts with the over-all stoping method design and that both require consideration in parallel to ensure success in mechanization."

Jan 1, 1990

By N. Aslin, R. Clark, G. Heferen

The methods of harvesting copper from stainless steel mother plates has been investigated from fundamental and operational experience perspectives. At least five different harvesting techniques have been identified that have different effects on product quality, current efficiency, current distribution, growth morphology and ease of stripping. Each method is examined from fundamental principles to understand what occurs during the harvesting process and why the particular effects are manifested. Experience from plants operating the harvesting method is provided to show that the fundamental understanding is relevant. Best practice harvesting method and harvesting management are described.

Jan 1, 2014

By Geoffrey Gilbert

Rossland is in the West Kootenay district; 5 miles north of the International boundary and 4 miles west of Columbia River at Trail. The first claim in the district was located in 1887; but there was little activity until 1890; when the showings that later became important were staked and development began. Production increased rapidly from 1; 800 tons in 1894 to a peak of 360; 000 tons in 1903; and averaged 286; 000 tons for the next 13 years. It declined sharply in 1917; and continued to decline until the closing of the main mines in 1928. Between 1933 and 1941 leasers mined a further 137; 000 tons. Total output has been about 6; 200; 000 tons; with average recovery of 0.47 oz. gold; 0.6 oz. silver; and 1 per cent copper. The total value was $82; 500; 000; of which aboµt three-quarters was in gold; the camp still leads the province in total gold produced. Ninety-eight per cent of the tonnage came from a small compact area worked by four inter-connected mines : the Le Roi (39 per cent); Centre Star (25 per cent); War Eagle (24 per cent); and Josie (10 per cent); all now owned by the Consolidated Mining and Smdting Company of Canada; Limited.

Jan 1, 1954

By A. M. Brown, P. V. Straznicky

Dimpling as a means of flush countersinking rivets is an old process predominantly used in secondary structures. The introduction of GLARE as an aerospace material has renewed interest in dimpling and its possible application in primary structures. The dimpling process is able to prevent the creation of a machined knife-edge in the thin aluminum plies of the GLARE sheets. In addition, dimpling eliminates the need to use reduced height rivets, such as the NAS 1097 rivet style. This investigation expands on an earlier study into dimpling of GLARE by Rans and Straznicky. In order to tailor the dimpling process to GLARE, FEM simulations were developed. After verification, a study was performed to find the best parameters for dimpling GLARE3-2/l. Coupon fatigue tests were carried out and the dimpled joints demonstrated increased fatigue lives over the conventional machine countersunk joints. Future wide panel fatigue tests are planned to confirm the usefulness of dimpling thin GLARE laminates.

Jan 1, 2006

By Fathi Habashi, Michel Pagé, Farouk T. Awadalla

"Chrysotile asbestos can be dyed with certain dyestuffs to form stable coloured products whose hemolytic and cytotoxicity are greatly reduced. Examples of these dyes are Thiazol Yellow G (a monazo dye) and Trypan Blue (a diazo dye). Other dye stuffs, for example, basic dyes with triphenyl methane structure, Brilliant Yellow (a diazo dye), and Methylene Blue (a thiazine dye) colour asbestos but do not reduce its toxicity. Similarly alizarin, 8-hydroxyquinoline, and representative members of the phthalein group Bromocresol Purple and Phenolphthalein.IntroductionThere is, at present, a controversy regarding the dangers of asbestos fibres, and attempts are being made to render it less toxic. One of these attempts consisted of treating chrysotile asbestos with gaseous phosphorus oxychloride, POCI], at ambient temperature and in absence of moisture. The product had to be heated at 300°C to 500°C to expel exess entrained reagent to get a material containing 0.5070 to 5% phosphate groups and known as Chrysophosphate (Lalancette and Dunnigan, 1982). This product showed decreased toxicity as measured by its hemolytic effect on red blood cells (fable 1). In another approach, Flowers (1983) showed that when chrysotile asbestos was thoroughly mixed with a solution of ferric ammonium sulphate and the slurry was then filtered and dried, the product showed a marked decrease in cytotoxicity.In the present investigation the problem of toxicity was considered from a different point-of-view. Chrysotile asbestos is a hydrated magnesium silicate that can be represented by the structural model shown in Figure 1 from which it can be seen that magnesium hydroxide groups, Mg(OH)2, form a part of the silicate structure. Certain organic reagents that are known to react with magnesium ion in solution to form chelates were reacted with asbestos to find out whether a chelate was also formed on the fibres, and if so , what will be the hemolytic action and cytotoxicity of the product."

Jan 1, 1991

By K. Yamaguchi

"This Precious metals content copper scrap is treated with a copper smelting process, and copper and precious metals are recovered. The precious metal lost in the slag is increasing with increasing of treated scrap amount. To determine the portion of the precious metals chemically dissolved and that associated with the mechanically trapped matte in the slag will be a key factor to improve the recovery of those metals. The distribution of precious metals between copper matte and FeOx-SiO2 slag phases is determined at 1300 oC and a fixed partial pressure of SO2 of 0.1 atm for the matte grades from 40 to 70 mass% of copper. The distribution ratios show a tendency to increase when the grade of matte is increased. In addition, the solubility of platinum and rhodium in the FeOx-SiO2-CaO slag under the air and the solubility of platinum in the FeOx-SiO2 slag equilibrated with a pure platinum or the Pt-Cu alloy were determined at 1300oC in the range of oxygen partial pressure from 10-9 to 10-7. The solubility of platinum and rhodium in the slag tends to increase with increasing content of copper in the slag and oxygen partial pressure. INTRODUCTIONThe stringency of the supply and demand of platinum group metal (PGM) intensifies by localization for resources and increase of the demand for PGM, furthermore, smelting and the recycling of PGM in the nonferrous smelting process take an important role. Scrap containing a precious metal for the purpose of collection of PGM is treated by copper smelting recently. With increase of the treatment amounts, loss of PGM in slags is the serious problem.In considering of PGM loss in slags, knowledge of the distribution behavior for PGM between slag and matte phases or slag and copper phases and the PGM solubility in slags is important. The distribution ratios of silver and gold between the FeOx-SiO2 slag and the Fe-Cu matte were reported by Roghani (Roghani et al., 2000), Shinha (Shinha et al., 1985) and Takeda (Takeda et al., 1993) However, there is no data for the PGM distribution ratio. On the other hand, the PGM solubility in slags was reported by Sano (Sano et al., 1997) However, there is very few report for the solubility of PGM in the nonferrous smelting slags."

Jan 1, 2012

By Marc Boyer

Modern civilization, modern industry, and modern standards of living, bring into, sharp relief the present-day essentiality of metals .and minerals, and the wide and diversified use which is made of them. Any attempt, therefore, to appraise the international situation today must take into consideration the metal and mineral resources of the world. If, as some believe, the world is divided into two distinct ideologies of political belief, one unalterably opposed to the other, so that armed conflict is unavoidable, then the question of national strength in mineral resources becomes of paramount importance. If, however, it is possible to avoid war by raising the standard of living in the underdeveloped ?areas of the world, thus ensuring all peoples everywhere against the dread spectres of starvation and disease, then the development of the world's mineral resources assumes even greater importance. Today it is difficult to realize that, prior to the industrial revolution in Great Britain, only a few of the metals and minerals now in common use entered into the everyday life of the people. !iron and steel, copper, lead, tin, and zinc, usually in .their unalloyed forms, along with the more common industrial minerals, were those most widely used, and then only in limited amount. With the advance of technology in metallurgy and in fabricating skills, the list of commercial metals and minerals has expanded until today they number more than eighty.

Jan 1, 1951

By Chris M. Healey

"The Jasper Gold mine in northern Saskatchewan produced a total mill feed of 140 127 tonnes at an average grade of 19.0 g/t Au. Both diamond drilling and chip samples from underground workings returned extremely high values, up to 12851 g/t (375 oz/T) Au over 0.10 meter from a chip sample. In the presence of such extremely high grades, the accurate estimation of reserves is a major problem.In the first part of this study, production data from the mine were used to evaluate the results of a variety of reserve estimation techniques in this environment. In two out of three cases studied, indicator kriging with assays cut to 342.9 g/t (10 oz/T) gave extremely good results. In the third case, however, indicator kriging gave unacceptable results. Instead, lognormal kriging of uncut data gave the best results.Secondly, from the same database, a number of drill-hole spacings were simulated, and reserves estimated from the simulations. As may be expected, the results of this analysis show increasingly better results with tighter drill-hole spacing. However, even with a 5 m by 5 m spacing the variation from actual grade was quite large. This is not a systematic under- or over-estimation of grade, rather a random scatter of results.The results of this study show very clearly the problems of deriving good estimates of reserves when extremely high-grade samples are encountered. There is a high degree of randomness to this data base, so reserve estimation in this situation will remain a high-risk operation."

Jan 1, 1993