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By Steve Custer, Chris Bennett, Patrick Garretson, Glenn Dobby, Jacques McMullen

"Barrick Gold is in the process of expanding one of its grinding circuits at the Goldstrike property as a response to both increasing ore hardness and increased ore sensitivity to finer grinding as it relates to gold recovery. The plant currently operates with two parallel grinding lines, each with a SAG mill, a pebble crusher, and a ball milling arrangement. As part of determining what additional equipment was to be required, a CEET evaluation program was conducted (CEET is an acronym for Comminution Economic Evaluation Tool). The work included: Development of a hardness ‘model’ for the ore body, as described by SAG Power Index and Bond Work Index;Site benchmarking surveys to fine tune the SAG and ball mill calibrations within CEET;Conducting CEET studies to examine the process options;Comparing CEET results to standard grinding circuit design techniques.The recommendation of the study, presently being implemented, is the installation of an additional ball mill on one of the two grinding lines. This paper reviews the sizing techniques applied, providing a CEET case study for circuit performance analysis and circuit design. OVERVIEW OF COMMINUTION AT GOLDSTRIKEOre feeding the autoclaves at Goldstrike are first processed through two parallel grinding lines. Both lines use SAG mills with cone crushing of pebbles followed by ball milling. A summary of the key circuit parameters is provided in Table 1. Line 1 primarily processes underground Meikle ore, although when no Meikle ore is available, it processes open pit Betze ore. Line 2 processes Betze ore exclusively. The Mill Line 1 P80 objective for Meikle ore is 74 microns. According to the recovery optimization analysis, a P80 of 90 microns was recommended for Betze ore. The potential however exists to perform co-mingling of both ore types and feed the higher grade Betze ore to Line 1, in which case the P80 of 74 microns would be retained."

Jan 1, 2001

By Mario Giavani

"IntroductionBy the 1980s, the continuous casting process had almost replaced the ingot casting of steel in Japan, Europe and North America. While economic benefits were probably initially the prime motivator, the transition rapidly proved that continuous casting in conjunction with ladle metallurgy offered a much greater degree of process control and made possible routine steel specifications not previously available.This new technology demanded improved procedures for the quantitative addition of the required metallurgical reagents, especially as regards the more volatile or toxic elements such as calcium , boron, carbon, sulphur, lead and tellurium. The injection of a thin steel tube containing the additive into the metal bath of a ladle refining station offers the best procedure for this. In the industry this has been referred to as ""Cored Wire "".Operators using this technology find that they are faced with balancing the injection speed against the small cross section of the tube to feed the required amount of reagent within the short time span available to the operation. Large-ladle shops requiring major quantities usually resort to multiple machines and high speeds. Many machines approach a maximum feed rate of 400 m/min. Higher speeds exceed the melting rate of the system, and the ferro static buoyancy of the tube will cause it to coil up the ladle wall and possibly resurface into the slag layer, and even eject itself above the surface. Under these conditions, exact control of element recovery becomes difficult, especially with the commonest addition, calcium silicon alloy.Many experts are persuaded that the final melting position of the carrier tube has major importance in establishing consistent element yield to the bath.For instance, the vapour pressure of calcium at l500 °C is close to I bar. Reaching a melting depth sufficient to accommodate this value is considered to be critical to achieving an acceptable and reproducible yield.Many studies have elaborated semi-empirical formulae to establish the melt zone depth, connecting this value essentially to the diameter of the tube , the injection rate and the superheat of the steel. The author's experience in steelmaking could not confirm such formulae in many cases, and he set about to develop a mathematical model which would be useful in addressing this problem, taking into account the several parameters which will regulate the behaviour of a filled tube immersed in molten steel."

Jan 1, 1991

Objectives ? New deposits can be found in mature Mining CampsNew Camps ? Volcanogenic Massive Sulfide (VMS) deposits ? polymetallicpolymetallicexamples are desirable exploration targets examples ? Genetic and exploration models for VMS deposits are robustrobust ? subtle but important differences exist between deposits and districts ? sometimes ??neglectedneglected??in resource modeling and exploration efforts ? ReRe-evaluation of a prominent existing camp is rewarding ? update on the exploration strategies currently being applied on a practical level The Falconbridge-Alexis approach includes GoCAD modelling

May 1, 2006

By R. Blazej

Machinery Systems Division (MSD) in the Institute of Mining Engineering at Wroclaw University of Technology specializes in belt conveying systems analyzing, calculating and design. Within the division operates the certified Laboratory of Belt Transportation (LTT) and Laboratory of Rollers. Since few years, a group of several people have begun work on developing a comprehensive system for the automatic evaluation of condition of conveyor belts working in the mines. Group uses both magnetic devices developed by specialized companies servicing belts and its own machine vision system developed for assessment of belts covers and edges during belt movement (up to 7 m / s) on the specially designed for this purpose the test conveyor. Recently they have got the research grant funded by the National Centre for Research and Development (NCBiR) for development of the system for automatic diagnosing of conveyor belts? condition and aiding of rational belt management. On the basis of previously created diagnostic tool called ABCDE (Automatic Belt Condition Diagnostic Equipment) the five modules: vision-A magnetic-B, preventive-C, forecasting?D, and determining safety factor-E will be developed. They will automatically interpret data about conveyor belts? condition to indicate the extent and timing of repairs, to prevent failures and to select the optimum moments for their replacements. The system will use results of ongoing research & development and planned research concerning modeling of belt wear using evolutionary genetic algorithms. The reached stage of research can not yet allow to start the implementation work by potential users. It is therefore necessary to pursuit research in real scale, the development of new modules (C-E) and intensive testing of the system in working condition with system calibration to optimize the economic effects.

Aug 1, 2013

By J. E. Hawley

"The zinc-lead deposit of the Lake Geneva Mining Company is on lot 7, con. VI, Hess township, Sudbury district, Ontario, about 10 miles northwest of the northern rim of the Sudbury Basin. Though a relatively small deposit, it shows some rather interesting relations to cross-cutting, pre-ore, quartz diabase dykes, which merit description.The deposit was discovered in October 1924 by J. H. Collins beneath iron-stained drift and oxidized sulphides. This proved to be the northwestern extremity of the orebody, the remainder of which extends southeast below swampy ground. Exploration began in 1927. In 1928 a vertical shaft was sunk to 250 feet and a level established at 235 feet. Later the shaft was deepened to 400 feet and new levels opened at 315 and 375 feet. In 1943 an inclined winze was sunk below the vein from the 315-foot level to a vertical depth of 640 feet, and two additional levels were opened at 525 and 615 feet respectively.The geology of the area has been described by T. T. Quirke (1), F. F. Osborne (2), F. J. Alcock (3), and Ralph Tuck (4). Private reports have also been made by Carl Tolman, J. E. Gill, and K. W. Fritzsche. Tuck's paper, covering the work completed to 1930, gives a detailed account of the character of the ore and enclosing rocks.Up to May 1944, when the property was closed, all ore above the 375-foot level and a small tonnage from below this elevation had been removed. Ore mined from 1941 to 1944 yielded the following:"

Jan 1, 1954

By David S. Wong

With air emission limits for total particulates continually tightening, management of `potroom dust' or airborne particulates from aluminium smelting potrooms is of increasing importance. To better understand how settled and airborne particulates are generated within a potroom, methodologies have been developed to sample and analyse the compositional signature of dust, in relation to its sources. During a smelter case study, these methods allowed tracking of mineralogical phases in dust across a range of potroom locations, showing that the mechanisms of dust generation do vary spatially and vertically in a potroom. Such methodologies may also be applicable to other metallurgical industries.

Jan 1, 2011

By Ronald G. Hamm

"With the advent in Canada of large open-pit equipment, the associated wire rope required must keep pace, especially in design and construction, along with the field that leads to increased rope life.This paper will first describe the various types of shovels and draglines in use today and also the unique characteristics of the wire rope required to efficiently service this equipment.Emphasis will be placed on the special equipment and techniques required in the wire rope manufacturing, along with the maintenance procedures required for a profitable operation.IntroductionOpen-pit and strip mining is increasingly playing an important role in the Canadian mining industry.An integral part of the surface mining industry is the excavation equipment used both to strip the overburden and remove the actual orebody. Two of the more prominent pieces of equipment are the electric power shovel and dragline. These two types of equipment have increased significantly both In size and number over the last decade.Wire rope plays a significant part in the operation of these machine s. Proper selection of the correct wire rope as well as proper maintenance procedures, can result in a major saving of a mine's wire rope consumption.The most prominent ropes for shovels are the hoist ropes. Some shovels also employ crowd and retract ropes. Boom pennants are manufactured from both wire rope or galvanized bridge strand.The most prominent ropes for dragline excavators are hoist, drag, and dump ropes. Some dragline excavators have boom hoist ropes, and most large dragline excavators have a boom suspension system using galvanized bridge strand."

Jan 1, 1983

By M D. Winning

The historical development of the elemental sulphur recovery industry in Western Canada is reviewed for the period 1952 to 1965. A brief technical description of a typical modified Claus sulphur recovery unit is presented. Some predictions are made concerning the future of the elemental sulphur recovery industry in Western Canada. THERE are evidences of sulphur or its compounds having been used for religious and medicinal purposes as far back as we have a recorded knowledge of history. As typical examples, sulphur was burned as a sort of inverse incense to drive away evil spirits at religious festivals, sulphur ointments were used by the early Egyptians to cure eye ailments, and hot sulphur-spring water was used as a cure for a variety of ailments. Thermopyle was called "Hot Gates" be-cause of its fame as a spa as well as a mountain pass. The Romans discovered the sulphur deposits in Sicily and mixed sulphur with bitumen for incendiaries; and, of course, anyone familiar with the travels of Marco Polo knows about the Chinese development of gunpowder, which contains sulphur. In some aspects things haven't changed much today. We still use sulphur-bearing ointments, and we still use the hot sulphur springs such as the one at Banff in Western

Jan 1, 1965

By D. J. MacDonald

UNDERGROUND development at the Lynn Lake property of Sherritt Gordon Mines, Limited, was begun in 1948 with the sinking of the A shaft in the area of the A orebody. By June, 1949, the shaft was completed to a depth of 1,024 feet. Twelve stations were cut, with the bottom level at 992 feet below the collar. Since completion of the shaft, lateral work has been carried out on the 12th level in order to expose the known orebodies and to provide openings from which deeper exploration could be conducted. Dur¬ing the change-over from sinking to lateral work, preliminary diamond drilling was done from the 12th level station to locate the A? ore-body. Later, drilling was carried out from the 5th and 9th level sta-tions, where, also, the outline of the A orebody was established. As the work progressed on the 12th level, and with the commence-ment of drilling below that level, the geological picture was found to be complicated by numerous faults. Instead of operating two drills it became necessary to use at least four. The original plans had provided air sufficient to drive two headings and to operate two diamond drills. The addition of two more air-driven drills resulted in a serious shortage of power.

Jan 1, 1951

By G. Ellie, D. F. Coates

"The mining of coal in thick and inclined seams is difficult, and there are only a few countries in the world that are really interested in the problems associated with their exploitation. In France a considerable amount of investment has been made in the mechanization of systems appropriate for such conditions.For seams inclined up to 50 degrees, of normal thickness, a new system was introduced in 1967. It consists of a longwall advancing to the rise with walking props, a shearer and hydraulic backfill. During the first two years the panel productivity was an average of 25 TN/MS, and they foresee the possibility of reaching an average of 30 TN/MS.A system for thick beds, both horizontal and inclined, is in p•rocess of being mechanized. In 1969 they started with a method consisting of a longwall in a footwall slice, or sub-level drifts with walking props, and caving and drawing up to a height of 20 m of coal. Recent experiments with a shearer have produced panel productivities between 9 and 11 TN /MS, and there is hope that with experience an average of 16 TN/MS will be obtained.In 1964 a method was initiated for beds inclined from 60 to 90 degrees, based on a mechanical cutter designed by the collieries in Lorraine. An overhand slice of 4.2 m in height is taken with a drum cutter mounted on the end of a boom. Hydraulic fill is placed at the completion of a slice. The face productivity, which has been from 13-20 TN /MS, can be perhaps increased to an average of 22 TN/MS. For those companies with important reserves in inclined and thick seams, these French systems may be worth the trouble of examining in some detail."

Jan 1, 1972

By A. A. Levinson, M. B. Kirkley, J. J. Gurney

"Scientific advances in the past decade have greatly clarified our understanding of certain concepts relating to the age and origin of diamonds. These advances are largely the result of geochemical studies of mineral inclusions in diamonds, made possible by modem analytical techniques which enable the accurate chemical analysis of micro-sized particles of the order of 200 microns in maximum dimension. As a generalization, the inclusions indicate that most diamonds formed from either of two rock types, peridotite and eclogite. Peridotitic diamonds have yielded ages of 3300 million years, whereas eclogitic diamonds areyounger and rangein agefrom approximately 1000to 1600million years. Kimberlite and lamproite, the two rock types usually associated with diamonds, typically are much younger than the diamonds they contain. Thus, it is now dear that kimberlites and lamproites are only the transporting mechanisms which brought diamonds to the surface and are in no way related to the formation of most diamonds. The latest concepts which developed during the past decade regarding the sources of carbon for the crystallization of diamonds from peridotite and eclogite, and the mechanisms of kimberlite and lamproite emplacement, IntroductionThe decade of the 1980s has seen major advances in our understanding of the age, origin and emplacement of diamonds. The information presented herein is applicable to virtually all natural diamonds, excluding diamonds related to meteorite impacts. There is still some question, however, as to the applicability of the new information to industrial grade ""fibrous"" or ""coated"" diamonds, and to microdiamonds (< 1 mm). In addition to drawing upon our own experiences, this review is summarized from a voluminous literature and for those interested in the original sources we recommend the books by Mitchell and Bergman (1991), Ross (1989), Nixon (1987), Mitchell (1986), Glover and Harris (1984) and Dawson (1980), and the review articles by Mitchell (1991), Gurney (1989) and Meyer (1985).are also discussed."

Jan 1, 1992

By Nigel J. Cook

"Detailed mineralogical examination of gold-bearing rocks, ores, concentrates and other samples should be considered an integral part of any study of a deposit for which exploitation is being planned. Adequate mineralogical study, although time consuming and often costly, can significantly improve understanding of the mineralization, can help to optimize the results of any metallurgical testing and can be of great value in case of potential trouble-shooting. The advantages and disadvantages of various examination techniques are discussed with reference to a number oj mineralogical studies oj Canadian gold-bearing samples.IntroductionVarious authors, notably Gasparrini (1983), Harris (1989) and Henley (1990), have stressed that mineralogical study of gold ores is critical to successful and efficient beneficiation. Only in cases where diagnostic cyanide leach testing is successful can detailed mineralogical examination be disregarded. Such examination of gold-bearing rocks and metallurgical products is all too often neglected because the methods involved are believed to be time-consuming, costly, and may carry a considerable degree of inaccuracy. Commonly, bulk metallurgical testing is, carried out without prior or concurrent mineralogical examination, causing the results of the testwork to be difficult to interpret, or in some cases, misleading. This, in turn, may lead to> significant delays to the project at the feasibility stage or mean that understanding of the sample is limited, preventing the introduction of prudent modifications at a later stage if problems arise. Mineralogical studies may guide the successful implementation of a metallurgical test program."

Jan 1, 1990

By C. -K. Fang

"Aging effect on the wear resistance of alumina particulate-reinforced 6061 aluminum matrix composites with a block-on-ring wear tester has been investigated. Specimens with various Al2O3 volume fractions of 0%, 10% and 20% were employed in this work. Experimental results indicated that over-aged monolithic 6061 Al had the best wear resistance, as compared with under-aged and peak-aged conditions. For the composite containing 10% Al2O3, over-aging and peak-aging resulted in similar wear resistance, which was higher than that for underaging conditions. For the composite containing a high volume fraction (20%) of Al2O3, the wear resistance reduced with the increase in aging time. Although longer aging time was favourable to the wear resistance of monolithic 6061 Al, it was detrimental to that for the Al2O3/6061 Al composite with high volume fraction of particles. IntroductionMetal-matrix composites (MMCs) have received attention in many engineering applications because of the demands for high specific strength (strength-to-weight ratio) and specific stiffness, good high temperature capabilities and wear resistance. The manufacturing processes of fiber-, whisker-, and particulate-reinforced MMCs have been well developed (Hosking et al., 1982). Because of the reduction in fabrication cost, the applications of MMCs have been widely extended to light weight-bearing sleeves, calipers, automobile parts (brake rotors, drive shafts, connecting rods, piston rings, and cylinder liners), sporting goods, aerospace components, tanks (wheels, speed brakes, and track shoes) and other industrial applications. Among the three types of metal matrix composites, particulate-reinforced MMCs are promising because of their homogeneous and isotropic material properties and low cost. Additionally, they can be formed using conventional metal processing techniques."

Jan 1, 2003

By C. H. Stockwell

RICE LAKE-BERESFORD LAKE area, situated 100 miles northeast of Winnipeg (Figure 1), is Manitoba&apos;s foremost gold mining district, although it is exceeded in gold production in the Province by the Flin Flon base-metal mining district. At present, the area is producing at the rate of about one and three-quarter million dollars annually, almost entirely from the San Antonio and Gunnar mines. The total production to date is about $14,000,000. Of this total, over $7,000,000 has come from the San Antonio mine, over $2,000,000 from the Gunnar mine, about $4,000,000 from the Central Manitoba mine, and the balance from several smaller properties. The writer has led Geological Survey parties in the area for the past four summers. The present paper gives a summary of the results of this work and also includes the findings of C. S. Lord, who was in charge of a party for one year. Much valuable information was obtained from earlier published reports on the area and from officials of mining companies, to whom the writer is indebted for their kindly co-operation. It is impossible in this short paper to give proper credit to the earlier workers or to discuss certain points o disagreement between their conclusions and those presented here. For further information the following references may be consulted.

Jan 1, 1940

By S. Joshi, E. Asselin

An electrochemical quartz crystal microbalance (EQCM) was used to study the leaching of pure gold in deaerated 1 M Na2S solution. Multiple cyclic voltammograms were measured between -0.76 and 1.242 V (SHE) at 20 mV/sec and 2 mV/sec and the frequency shift of the quartz crystal was simultaneously measured. Both the forward and reverse scans showed oxidation occurred between -0.40 to 0.20V. The frequency shift increased during both the forward and reverse scans in the potential range of -0.40 to -0.06 V indicating electrode mass decreased. Since at -0.40 to 0.20 V oxidation peaks were also observed, part of the oxidation was due to oxidation of gold. Eh-pH diagrams were constructed and showed soluble Au(I)-S(IV) species formed between -0.30 and 0.10 V (SHE). Atomic absorption spectroscopy of the test solutions and the mass change recorded by EQCM both showed about 0.015 mg of gold leached. Since the majority of the frequency shift increase corresponding to gold oxidation occurred at -0.40 to -0.06 V during multiple cyclic voltammogram measurement, the total leaching of gold could be approximated to occur at this potential interval to give a leaching rate of ca. 6.4x10-5 mg/s-cm2.

Jan 1, 2011

By D. Bois, P. Keating, J. Lemieux, M. A. Vallée, M. Allard, R. S. Smith, L. Z. Cheng, M. Chouteau, D. K. Fountain

"Abstract -A test survey using the MEGATEMII airborne electromagnetic system was flown over the Iso and New Insco massive sulfide orebodies in the Rouyn-Noranda mining camp, Canada. The results were compared with data from historical systems (INPUT, DIGHEM) used to discover the deposits. The historical data show that the two deposits have comparable conductances. However, the modern MEGATEMII system reveals that the New Insco deposit has a much slower decay than the Iso deposit, and it is, therefore, interpreted to be more conductive. The MEGATEMII anomaly maps provide estimates of the location, depth, dip, and strike of the two deposits, information that was not available from the historical anomaly maps. The signal-to-noise ratio of the MEGATEMII data is greater than the historical data, yielding more sharply defined anomalies. The investigations also included a comparison between 90 Hz and 30 Hz MEGATEMII data. The 90 Hz data were found to be useful for mapping the less conductive parts of the Iso body, whereas the 30 Hz data demonstrated that the New Insco body is more conductive. Analysis of height attenuation data over the Iso body indicates that the body could be seen by the MEGATEMII system if it were buried an additional 230 m deeper (in highly resistive material). On the other hand, the INPUT system would detect the Iso body only if it were buried no deeper than an additional 60 m. Tests with the transmitter turned off showed that, for this flight, the MEGATEMII system noise levels on the processed data are about 300 pT/s. Sommaire - Dans le cadre d’un projet de recherche, un ensemble de levés d’essais électromagnétiques aéroportés employant le système de MEGATEMII a été effectué au dessus des dépôts d’Iso et de New Insco, Rouyn-Noranda, Canada. Les données ont été comparées avec les réponses des systèmes qui ont découvert ces deux dépôts (INPUT et DIGHEM). Les données antérieures montrent que le dépôt d’Iso a une conductance comparable à celle de New Insco. Cependant, les données de MEGATEMII démontrent que le dépôt de New Insco a une haute valeur de la constante de décroissance, ce qui reflète une plus forte conductivité. La carte d’anomalies de MEGATEMII indique la localisation, la profondeur, le pendage et l’orientation des deux dépôts, ce que la carte d’anomalies antérieure ne montrait pas. Le rapport de signal à bruit de MEGATEMII est plus grand que celui des données de INPUT et de DIGHEM; de plus, les pics sont mieux définis. Les tests ont également permis une comparaison entre les fréquences de base de 90 Hz et de 30 Hz. Les données de 90 Hz se sont montrées utiles pour cartographier la partie du dépôt Iso dont la conductivité est la plus faible, tandis que les données de 30 Hz montrent clairement que le dépôt de New Insco est plus conducteur. Les analyses de l’atténuation du signal avec la hauteur ont indiqué que le dépôt d’Iso pourrait être détecté par le système MEGATEMII s’il était enfoui à 230 m sous la surface (dans un milieu hautement résistant). D’autre part, le système INPUT pourrait seulement détecter le dépôt d’Iso s’l était situé à 60 m de profondeur. Les tests avec l’émetteur fermé démontrent que le niveau de bruit est des l’ordre de ±300 pT/s."

Jan 1, 2006

By U. Dillon, G. Blackwell

"Geographic information systems (GIS) provide an efficient means for the recording, manipulation, revision, display and analysis of spatially referenced data. GIS are widely used at the exploration stage of mine development, and are increasingly used for reclamation planning. The ability of a GIS to perform spatial searches and query spatially referenced data make it a powerful tool for use at all stages of mine development. As the amount of data available for analysis increases, so does the power and flexibility of GIS as a planning tool.Starting from the exploration database, this paper describes how a GIS can be used for the development of mining plans based on topography, geology and mineralization information stored in a relational database. Planning decisions approaching the optimal can then be made for a wide range of parameters, including stockpile and waste dump locations, the location of potentially acid generating and neutralizing material for dump design, profitable and risk-controlled mine extraction sequencing, and haul road locations. This is made possible by the overlay and buffer analysis capabilities of a GIS which are explored and exploited to produce a continuous mine production planning program, as well as site remediation and reclamation using a successful case study. IntroductionGeographic information systems (GIS) are a relatively new tool in the mining industry. Although they have existed for a number of years, the potential of GIS for mine management and planning is only beginning to be investigated and exploited. The unique spatial capabilities of GIS make them particularly wellsuited for use in mining, where spatial information is fundamental to the processes of mineral exploration, mine development, and environmental reclamation. A number of potential applications for GIS in the mining industry have been identified, and they are widely used for exploration and reclamation. The use of a GIS as a platform for the development of mine planning routines and software remains an interesting, but as of yet unexplored, application of this technology."

Jan 1, 2003

By A. Warczok, T. A. Utigard

"Slags from smelting of copper concentrates contains from 1 to 15% of copper. Copper is present in the form of copper or copper matte inclusions of size from 2 to 1000 micro, and as dissolved cuprous oxide. Removal of the copper requires the slag reduction, primarily reduction of magnetite and co-reduction of cuprous oxide. Thus, the kinetics of the slag reduction play an important role in copper recovery. Instantaneously, at the contact of carbon and a slag the gaseous film is formed. The magnetite and cuprous oxide reduction is going through a gaseous film, separating the slag and carbon of a coke or electrodes. The thickness of a gaseous film grows to a critical value and gas bubbles, containing CO and CO2, are created and rise up in the slag. Results of measurements of kinetic of the slag reduction with graphite showed high value of activation energy, close to the value of activation energy of Boudouard reaction. Strong temperature dependence of the reaction rate points out the thermal instability of the reacting system. It was found that the slowest process in the reduction stages determines the loop of CO and CO2 transfer and magnetite diffusion to the slag/gas film boundary. Strongly endothermic Boudouard reaction seems to cause thermal instability on the reaction surface. So, heat transfer to the reaction surface is very important. Due to low thermal conductivity of a slag the convection dominates in the heat transfer. So, any slag stirring accelerates the rate of reduction and coalescence of metallic copper or copper matte inclusions."

Jan 1, 2015

By T. G. Joseph, G. W. Hansen

"This paper considers the duty cycle of an electric cable shovel and correlations with measured passive seismic responses of the underfoot oil sands material in-pit. It has been observed that the cyclic activity during operation of any shovel in the oil sands environment causes the material to deteriorate and provide a less than ideal footing for this large item of equipment, whose dead weight approaches 1500 tons with a footprint of merely 75 sq. yd. Consequences are manifested in the form of carbody and side frame cracks, and associated downtime, maintenance activity, cost, and subsequent loss of availability.The objective of these considerations, as part of the Oil sands-Equipment Interaction Program (OsEIP), currently a joint venture between Syncrude Canada Ltd., James Progithin International (JPi) Ltd., Caterpillar Inc., P&H MinePro and the University of Alberta, is to identify and provide feedback to the manufacturer and end user of adverse shovel-ground conditions. This would enable the manufacturer to incorporate greater knowledge into the design process and the end user to direct operations in an enhanced proactive maintenance stance."

Jan 1, 2002

By I. S. Thompson

"Exploration properties form a continuum from grass roots to those with favourable geology, geochemical and/or geophysical anomalies, mineralization, showings (prospects), and finally to those with defined mineral deposits. Often, properties exhibit a composite of these categories.The most problematic to value are properties or deposits that are not economically exploitable at the time of the valuation due to a lack of exploration, insufficient grade or tonnage, poor mining conditions, or the imposition of socio-economic, environmental, or legal constraints.Various acceptable methods of valuing the range of all such mineral properties or deposits are reviewed. Some less appropriate methods are also discussed."

Jan 1, 2002