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By G. M. Ritcey, S. H. Lucas

"On the north shore of the St. Lawrence River, in Quebec, are located orebodies of low-grade titaniferous magnetite. The Quebec Mining Exploration Company (SOQUEM), who have an interest in the deposits, believed that beneficiation of the could generate sufficient revenue to defray the mining costs and the costs of transporting the ore to a steel production facility. A joint research project of SOQUEM and CANMET investigated alkaline roasting of a magnetic concentrate, followed by leaching of the calcine and separation and recovery of Cr and V by solvent extraction. Aluminum was recovered by precipitation.The present paper describes the roast-leach bench-scale and pilot-plant work leading to the development of the optimum conditions f or the integrated process.A plant flowsheet was developed for the treatment of 5 x 106 tons of magnetic concentrate per annum. Estimates of capital and operating costs were made.Based on a recovery of approximately 90% V, 85% Cr and 75% AI, the total hydrometallurgical plant fixed capital costs, including mining, concentration and shipping, are estimated at $1.021 x 109; the operating costs are estimated at $131.92/ton concentrate. Annual revenue from the Na2CrO4.H2O, V2O5 and A12O3 produced is calculated to be $421 x 106.IntroductionThe Quebec Mining Exploration Company (SOQUEM) acquired in 1968 an interest in four titaniferous magnetite orebodies located in Eastern Quebec. 85 miles north of Mingan on the north shore of the St. Lawrence River. The Mingan deposit, with an estimated tonnage of one billion tons, has a reported average grade of 43% Fe, 6.3% Ti , 1.60% Cr, 0.19% V and 6.1% Al with minor amounts of nickel. SOQUEM, on the basis of previous bench-scale data, believed that the recovery of chromium, vanadium and alumina by alkaline roasting would generate sufficient revenue to defray the mining costs and the costs of transporting the ore to a steel production facility on the coast. One of the approaches selected by SOQUEM for beneficiation of the ore consisted of a combination of magnetic concentration followed by alkaline roasting of the calcine."

Jan 1, 1980

By Theo Mayer

Presentation Outline Define data visualization in the context of workflow Present other industries? application and demonstrated benefits Provide conceptual tools to help you address a visualization strategy Hold 10,000 foot view ? to touch on many issues

May 1, 2008

By B. J. Morash

"The six mineable coal seams at Quintette Coal Limited (QCL) vary in thickness from 0.75 m to 9.5 m and include waste partings varying from 0.2 m to 4 m thick. They are highly faulted and folded in some areas and dip angles range from horizontal to 90 degrees. Due to this variation in thickness and orientation of the seams, several different mining methods are used to economically recover the coal. The key to QCL's success depends on the timely collection of detailed geology data and on mine planning which allows selection of the best method of mining to achieve maximum coal recovery with minimum dilution and cost. This paper will describe the various methods of mining employed and the criteria used to select them. IntroductionThe unique challenge in mining at Quintette Coal Limited (QCL) is to extract large quantities of coal and waste, from a complex orebody, with constricted areas for mining and waste disposal. This challenge dictates the mining of as many as four 10 m benches per year, through complicated coal structures, from three separate open pits with a total of 19coal seams. This total is made up of 5 seams at Mesa, 8 seams at Wolverine and 6 seams at Shikano (Fig. 1).Computer-aided mine planning and scheduling is carried out on a routine basis to ensure the prudent selection of methods of mining, to produce plans which ensure delivery of appropriately blended raw coals to the plant, and to coordinate disposal of large quantities of waste.Several methods of mining are applied simultaneously, and as a result coal and waste are released at different rates from twelve to fifteen mining faces. In order to ensure uninterrupted flow of material from excavators and to utilize the truck fleet effectively, a computerized dispatch system is employed.GeologyGenerally, geological conditions can be related to structural (faults and dip angle) and/or stratigraphic (coal seam and interseam waste thickness) sources"

Jan 1, 1988

By Richard D. Moffett

The MineSight® Implicit Modeler arms geologists, engineers and surveyors with a better approach to 3D modeling. Use the tool to quickly retrieve a 3D wireframe from drillhole data and onscreen interpretation. Generate faster and more informed decisions to guide future work and improve reproducibility of results. Implicit Modeling is a mathematical surface fitting method that interpolates points to give a smooth and realistic fit. Control results by mixing planar, sectional and non-orthogonal polygons or polylines, as well as drillhole information to create solids or surfaces. The outcomes are particularly valuable to identify ore body trends, generate 3D contours of drillhole intercepts, or produce cut-off 3D maps. MineSight Implicit Modeler (MSIM) is fully integrated in MineSight?s robust and versatile suite of products, allowing you to interpret, interpolate and calculate while moving between applications. It connects seamlessly with the MineSight Torque SQL database, offering access to extensive filtering options. MSIM makes modeling much faster, allowing geologists more time to analyze data and test theories. The presentation will reveal how MSIM complements MineSight?s geomodeling workflow.

May 1, 2013

By M. Ghiani, P. Carbini, R. Ciccu, C. Del Fà

"This paper is concerned with the problems inherent in the efficient and economical processing of the fine fractions of a coal from the Sulcis basin (Sardinia, Italy) whose characteristics are typical of low-rank coals occurring in the Mediterranean region. Three different techniques, based upon surface properties, are examined. Flotation can be very efficient from both a technical and economic point of view, provided care is taken in the modulation of the flotation pulp. Interesting results have been obtained with oil agglomeration and this method could be economically feasible. Finally, electrical separation has proven a viable technique, although it entails preliminary drying.Besides discussing the problems encountered in the experimental research, some significant results of general validity are also given. They demonstrate that cleaned products can be obtained with fairly interesting recoveries, thus opening the way to advanced research aimed at setting up the most suitable technique for industrial application. IntroductionAs a result of the oil crisis, which caused a major upset in world energy supplies, the last ten years have seen a revolution in the energy policies adopted.In particular, the status of coal, which seemed destined to decline in view of the availability of liquid fuel, has had to be re-examined. The need to meet energy demands under improved reliability conditions and controlled prices through a broader and more flexible diversification of sources of supply has evoked, especially in highly industrialized countries, a renewed interest in coal. The result has been a consistent increase in demand and production as well as investments in new mines and the reinforcement of the infrastructure.This turn of events has also lead to a re-evaluation of young low-rank coals, hitherto considered uneconomical and thus neglected, because of their low heat value. In fact these coals, which have a high ash content, may also be relatively highly contaminated with sulphur. The above drawbacks, which still today preclude the widespread use of these coals, are bound to create even greater problems in the future as increasingly restrictive environmental control imposes, without exception, recourse to cleaner fuels."

Jan 1, 1986

By Stewart A. Ferguson

Location.-The property consists of eight claims (P-12339 to 12343, 12403 to 12405) in Robb township, adjoining Jamieson township on the west. A mocor road extends twenty-two miles northwest from Timmins to the mine. Acknowledgments.- The field work was done in 1940 and 1943, while the writer was employed by the Ontario Department of Mines. The Metals Reserve Company has made available information regarding the property through Messrs. W. R, Dunbar, of Hollinger Consolidated Gold Mines, and W. C. Ringsleben, of the Metals Control Board, Department of Munitions and Supply.

Jan 1, 1945

By J. M. Beeckmans, S. G. Butcher, M. Goransson

"The counter-current fluidized cascade is a novel and potentially efficient pneumatic gravity separation device. Data are presented on over 150 runs of cleaning Alberta thermal coals, covering several size ranges. The coarser sizes of coal were processed in admixture with a fluidizing medium consisting of 0.5-by 0.1-mm hematite (or magnetite) and limestone particles. The partition curves for coal particles larger than about 3 mm, mixed with fluidizing medium, showed that the sharpness of separation achievable with the cascade approaches that of wet heavy medium processes, whereas with particles in the size range of 3 by 0.6 mm the sharpness of separation was comparable to that of a Baum jig. Useful cleaning was also achieved with particles smaller than 0.6 mm , Throughput rates of up to 11 tonnes per metre width of cascade per hour were achieved, with no indication of a deterioration in performance.IntroductionPneumatic coal beneficiation has steadily lost ground vis-a-vis hydraulic beneficiation during the past quarter century, primarily because of the sharper separations achievable with the latter methods. Nevertheless, there are certain inherent advantages of pneumatic separation methods which would give them an advantage in the market place were it possible to increase their efficiency to be technically competitive with those of hydraulic processes. These advantages are a dry product, resulting in a higher calorific value per ton, and avoidance of the problems associated with treatment and storage of process waste waters. Also, although it may be necessary to dry the raw coal prior to pneumatic processing, the dry rejects produced constitute an ideal fuel for a fluidized-bed combustor, which could provide heat both for drying the coal and for other purposes."

Jan 1, 1982

By Desmond M. Levins

"Australia has almost twenty per cent of the Western World's low-cost uranium reserves, located mostly in the Alligator Rivers region of the Northern Territory. At present, only one uranium mill is operating in Australia, but a number of new mills are planned for the early 1980s.Details are given of Australian uranium mining and milling proposals and the measures taken to minimize their environmental impact. Major factors affecting environmental impact are discussed, including treatment of liquid wastes, water management, control of radon and other airborne releases, and disposal of tailings. IntroductionAustralia is entering a new phase in uranium mining and milling activity . In the first phase of operations, between 1954 and 1971, about 10,000 tonnes of yellowcake was produced at five locations. Most of the production came from the mines at Rum Jungle in the Northern Territory and Mary Kathleen in Queensland. In the 1960s, the demand for uranium slumped, and much of the yellowcake produced at Rum Jungle was stockpiled by the Australian Atomic Energy Commission. The early uranium processing operations in Australia were typical of overseas practice at that time. Environmental problems were generally given low priority and pollution control measures were unacceptable by today's standards. There was little or no recycling of process water, acid waste streams were not neutralized and tailings dams were poorly designed. At Rum Jungle, oxidation of sulphides in waste heaps, tailings dumps and ore stockpiles subsequently led to destruction of vegetation and heavy metal pollution in a nearby river.In the early 1970s, major uranium deposits were discovered in the Alligator Rivers region of the Northern Territory. Significant orebodies were also located in the Great Artesian Basin in South Australia, in calcrete formations in Western Australia and at several locations in Northern Queensland. According to latest available estimates. Australia has about 160/0 of the Western World's uranium recoverable below $US 80 per kg U. Mining these orebodies will require pollution control measures more stringent than practised previously in Australia."

Jan 1, 1980

By J. E. Nesset

"As an alternative to conventional dewatering by vacuum filtration and oil-fired rotary dryers, Brunswick Mining conducted extensive pilot-scale testwork on its copper, lead, zinc and bulk concentrates using a Larox Oy (Finland) automatic pressure filter. The results showed that pressure filtration readily produced final cake moistures of 6-8.5 per cent on this very fine sulphide material.An in-depth analysis examines pressure filtration in terms of metallurgical performance and projects energy savings of 78 per cent for pressure filters over the current dewatering operation. Potential energy and operating cost reductions are also estimated.IntroductionVacuum filters followed by oil-fired rotary dryers are one of the most common means of dewatering mineral concentrates. They represent, however, a level of technology which is exceedingly wasteful in terms of manpower, space utilization equipment and fossil fuel dependence. In addition, the use of thermal dryers is leading to increased environmental concerns both in plant and out.These were the primary factors which prompted Brunswick Mining to consider alternative dewatering methods as the existing equipment came up for replacement and upgrading. In late 1979, company engineers were encouraged by automatic Larox pressure filters seen at several Scandinavian operations. Subsequent laboratory tests by the manufacturer (Larox Oy of Finland) on several concentrate samples were sufficiently promising for Brunswick and Noranda to lease a trailer mounted filter-lab unit and a technician from Larox for a five-week period. Extensive on-site testwork on all four Brunswick concentrates (zinc, lead, copper and 'bulk' lead-zinc) confirmed the potential of pressure filtration."

Jan 1, 1982

By J. P. Grieco, F. W. Grieco

"Manufacturing of Jaw CrushersOriginIn 1858 Eli Whitney Blake invented the first successful mechanical rock breaker-the Blake-type jaw crusher. Blake adapted a mechanical principal, the powerful toggle linkage system used to transform rotating motion and energy into oscillating mot ion and tremendous compressive forces. Today these same principals apply and the basic Blake-type jaw crusher is one of the leading machines of its class for heavy duty primary crushing service.In 1881 Philetus W. Gates patented a design for a crusher, the forerunner of the modern gyratory crusher which dominated the field from the late 1800s to the early 1900s. In 1910 the largest gyratory crushers built had 48-inch openings. However, about this time the jaw crusher came to life when the Power and Mining Machinery Co. built an even larger sized opening crusher-a giant 84-inch by 60-inch jaw crusher for a trap rock quarry in Pennsylvania. A 24-inch gyratory crusher became the ideal sized secondary machine for this size jaw. From that time on jaw crushers were looked on favourably as primary breakers and lines were brought up to date to parallel the already developed gyratory lines.FunctionMost heavy duty Blake-type jaw crushers work basically the same way. They are ruggedly designed and capable of crushing material in some cases in excess of 80, 000 p.s.i. compressive strength. They are very simple machines with few moving part s and, with the exception of replacement of renewable parts, are relatively maintenance free. It is quite common to have these machines in product ion for 20 to 30 years. The following will de scribe how these machines work. Large-diameter high-inertia flywheels which are connected to the main eccentric shaft, rotate inside a connecting rod type mechanism called a Pitman. It transforms rotating motion into vertical oscillating motion. This vertical motion is in turn transformed into reciprocating mot ion by means of a system of 2 toggles, each connected to the Pitman. The rear toggle is connected to the fixed rear head, and the front toggle is connected to the swing jaw which is hinged at the top of the crusher. With each rotation of the eccentric shaft the swing jaw opens and closes on rock which is fed into the crusher chamber, crushing the rock in a series of bites. These bites, or strokes as the y are called, usually vary between 1/2 inch to 1 1/2 inch at speeds of 120 to 200 strokes per minute. The reduction ratio of feed input to discharge is usually about 8 to I. Output capacities can vary from 100 tons/hour to 1200 tons/hour depending on the size of machine and its discharge opening. Horsepower requirements can vary from 75 hp to 400 hp.The entire crusher chamber is lined with replaceable 14070 manganese steel liner plates. This material is ideally suited for the job since it hardens as it wears during crusher operation. Manganese is also used in the high wear areas at each end of the toggle plates."

Jan 1, 1985

By A. G. Matyas, B. Wasmund, R. C. Francki, K. M. Donaldson

"The construction of large. high-power electric furnaces has been an important factor in the growth of electric smelting technology . New developments in the design and operation of electric furnaces have been spurred by the escalating cost of electric power and increasingly stringent environmental constraints. Key areasofprogress include the application of high voltage to enhance furnace productivity; the installation of novel furnace cooling elements and robust binding systems to extend furnace life; development of process schemes to reduce power consumption by preheating and prereduction of the charge; and environmental control improvements for handling fine dusty feedstocks, and for furnace sealing.This paper reviews these developments and outlines a systematic approach for their application in the custom design of new or retrofit electric furnace facilities.IntroductionThe use of electric smelting furnaces has continued to progress during the last decade. Electric furnaces offer high throughput capacity and productivity. In addition, they produce minimum environmental impact, as the furnaces can be readily sealed, and only a small quantity of off-gas is generated. Electric furnaces present the most favourable choice of smelting technology where high process temperatures in excess of about l400°C are required.Their application is burdened by the escalating cost of electric power, hence it is important to seek new opportunities through further technological development. This paper reviews recent developments in the design and operation of high-power electric smelting furnaces, in the following areas:"

Jan 1, 1993

By T. G. Carter

"During the early part of the 1980s, four new surface coal mines commenced operation in the Province of British Columbia. Each represented a major investment in both persons and materials in order to protect this investment in one significant area-the fixed portion of the surface coal handling system-a substantial amount of work was undertaken to ensure that the system was well protected from an outbreak of fire. A great deal of effort in this field had already been made by those coal mines which had been in operation for a number of years and experience gained at these operations was utilized in determining the level and extent of fire protection for the new mines.This paper summarizes the major problems, and suggests some of the methods of solution, in providing an adequate degree of fire protection for surface coal handling systems. It will also discuss the potential for gas and dust explosions together with ways to minimize this potential.The Fixed Coal Handling SystemNote: The word ""fixed"" has been used in its present context to denote that part of the coal handling system where the coal is moved via fixed installations such as a conveyor. It differentiates from that part of the system where coal is moved by mobile equipment.The raw coal delivered to the truck dump will undergo two major processes on its way to the rail load out. The first will be at the coal preparation plant where coal of specified quality will be extracted from the raw feed to the plant. If this coal is of metallurgical quality, and sometimes if it is of thermal quality, it will pass through a thermal dryer where part of the moisture acquired during coal preparation will be removed, i.e. the second process. As the complexity of both the coal preparation plant and the thermal dryer is such as to warrant separate considerations they will not form part of this paper. Each of the processes, however, is generally, housed in its own building, thus, containment of any hazards is usually more attainable than those existing or caused in the rest of the system."

Jan 1, 1988

By J. P. Grieco, F. W. Grieco

"Manufacturing of Jaw CrushersOriginIn 1858 Eli Whitney Blake invented the first successful mechanical rock breaker-the Blake-type jaw crusher. Blake adapted a mechanical principal, the powerful toggle linkage system used to transform rotating motion and energy into oscillating mot ion and tremendous compressive forces. Today these same principals apply and the basic Blake-type jaw crusher is one of the leading machines of its class for heavy duty primary crushing service.In 1881 Philetus W. Gates patented a design for a crusher, the forerunner of the modern gyratory crusher which dominated the field from the late 1800s to the early 1900s. In 1910 the largest gyratory crushers built had 48-inch openings. However, about this time the jaw crusher came to life when the Power and Mining Machinery Co. built an even larger sized opening crusher-a giant 84-inch by 60-inch jaw crusher for a trap rock quarry in Pennsylvania. A 24-inch gyratory crusher became the ideal sized secondary machine for this size jaw. From that time on jaw crushers were looked on favourably as primary breakers and lines were brought up to date to parallel the already developed gyratory lines.FunctionMost heavy duty Blake-type jaw crushers work basically the same way. They are ruggedly designed and capable of crushing material in some cases in excess of 80, 000 p.s.i. compressive strength. They are very simple machines with few moving part s and, with the exception of replacement of renewable parts, are relatively maintenance free. It is quite common to have these machines in product ion for 20 to 30 years. The following will de scribe how these machines work. Large-diameter high-inertia flywheels which are connected to the main eccentric shaft, rotate inside a connecting rod type mechanism called a Pitman. It transforms rotating motion into vertical oscillating motion. This vertical motion is in turn transformed into reciprocating mot ion by means of a system of 2 toggles, each connected to the Pitman. The rear toggle is connected to the fixed rear head, and the front toggle is connected to the swing jaw which is hinged at the top of the crusher. With each rotation of the eccentric shaft the swing jaw opens and closes on rock which is fed into the crusher chamber, crushing the rock in a series of bites. These bites, or strokes as the y are called, usually vary between 1/2 inch to 1 1/2 inch at speeds of 120 to 200 strokes per minute. The reduction ratio of feed input to discharge is usually about 8 to I. Output capacities can vary from 100 tons/hour to 1200 tons/hour depending on the size of machine and its discharge opening. Horsepower requirements can vary from 75 hp to 400 hp.The entire crusher chamber is lined with replaceable 14070 manganese steel liner plates. This material is ideally suited for the job since it hardens as it wears during crusher operation. Manganese is also used in the high wear areas at each end of the toggle plates."

Jan 1, 1985

By Tim J. Carew, Dennis C. Martin

"One approach to stabilization of rock slopes is to place a buttress at the toe of the slope to provide additional resisting forces and increase the length and strength properties along the failure surface. This paper describes the rock mechanics and mine planning aspects of incorporating a buttress of intact rock in the lower part of the slope as part of the slope design for the south wall of the final pit at Cassiar Mine. Stability analysis techniques and results are described. Analyses results have indicated that, in order to maintain steep over-all slopes in the final pit, a buttress of intact rock shoud be incorporated into the lower section of the slope until late in mine life. The effect of the buttress is to flatten the slope and reduce the slope height thereby improving slope stability. The mining plans would be such that the buttress would be mined out during the last four months of mining when the consequences of instability would be least severe.IntroductionThe concept of using a buttress to stabilize slopes has been used in mining and civil engineering construction in may locations (Richards and Stimpson, 1977). Most buttresses involve placement of coarse rock fill timber cribs or other material as a load at the toe of an already unstable slope to provide forces which resist failure by counteracting driving forces and increasing the length and strength of the failure path.This paper describes the geotechnical and mine planning aspects of incorporating a buttress of intact rock in the design of the south wall of Cassiar Mine. The effect of an intact rock buttress is to flatten the slope and reduce the slope height, thereby improving slope stability. No actual construction is required other than normal excavation of the slope. The ""mine plans would be such that the buttress would be mined out at the end of mine life when the impact of instability would be less severe and additional ore might possibly be recovered from the slopes. Mining of the buttress could induce instability at the very end of mine life at a time when maximum ore extraction has been achieved."

Jan 1, 1986

By L. C. Galloway, P. M. Tiley

"Some progress has already been made in defining the parameters which will determine the performance of a guidance system in a mine shaft. Very little information is available, however, to help designers or operators predict the effects of varying these parameters in new or existing installations.The experience we have gained from monitoring a variety of installations has led to the development of a model which simulates the motion of a conveyance as it moves through a mineshaft, restrained by fixed guides.This paper presents a general analysis of the performance of the guidance system used in several installations, as well as a detailed description of the problem encountered at one mine and the steps taken to solve it.IntroductionOur company has investigated in some depth the problems that arise in the guidance of mine hoist conveyances.We have a telemetering accelerometer which we obtained to test mine hoist brakes. Frequently, during brake tests, the mine owners request us to use this instrument to measure the lateral motion of the conveyance ""to check guide alignment"". We have made such tests in shafts that have guide s of different kinds, including wooden guides, steel rail s and tubular steel guides. From these tests, we have gained some valuable information about guidance systems.In a well-aligned guidance system that is designed within common and well-known practice, the conveyance will experience very little shock most of the time. However, on rare occasions, shocks up to .5 g will occur. That is, the conveyance exerts a force of up to half its loaded weight on the guide. If the guide slips or is damaged by this force, it will be misaligned for future trips and become the cause of future shocks. In time, the whole guidance system can become misaligned."

Jan 1, 1982

By P. R. A. Andrews, I. Jackman

"A mineral processing investigation to recover chromite was performed at Lakefield Research, under the guidance of CANMET personnel, on a 70 tonne ore sample from the Bird River deposit in Manitoba. In the laboratory phase a flowsheet was developed which involved grinding, gravity separation and flotation. The gravity concentrates were upgraded by magnetic separation and the flotation concentrates by gravity concentration . Pre-concentration by electronic ore sorting, magnetic separation and heavy media separation also was examined.The developed flowsheet was applied on a pilot-plant scale in the second phase of the testwork to the ore as received, and to ore pre-concentrated by electronic ore sorting and magnetic separation. Ore pre-concentrated by heavy-media separation was treated on a laboratory scale based on the pilot-plant flowsheet ,Processing the are as received resulted I n 77% recovery of chromite in a concentrate analyzing 30% Cr20 J; processing are pre-concentrated by electronic are sorting resulted in 64% recovery of chromite in a concentrate analyzing 30.5% Cr20J."

Jan 1, 1988

By K. Swedburg, M. Samuels

"The expansion of the concentrator at New Gold’s New Afton copper-gold mine in British Columbia, Canada, completed in 2015, included an increase in the required retention time of the cleaning circuit. On site pilot testing of a Woodgrove Staged Flotation Reactor (SFR) had shown that a high grade copper concentrate would be produced with excellent recovery. The SFR was selected rather than conventional tank cell technology based on the much smaller footprint (which rendered a separate and expensive building extension unnecessary), high concentrate grades demonstrated in testing, and the lower energy requirement. Three SFRs, each capable of taking a nominal feed of 700 cubic meters per hour were installed and commissioned 10 months after the receipt of order. The SFRs operate in series and all of the cells produce a final concentrate typically grading 32% Cu, while the overall SFR stage recovery averages 55%. The tailings from the SFRs are treated in the original conventional three-stage cleaner circuit where the remaining values are recovered in a concentrate grading 28% Cu. Design production was achieved within days of the initial start-up of the SFR circuit.INTRODUCTIONThe New Afton concentrator, located near Kamloops, British Columbia, Canada processes a copper-gold ore with a designed head grade of 0.96% Cu, 0.72 g/tonne Au, and 2.22 g/t Ag.The New Afton Mine is a block cave mining operation. Ore is undercut from the bottom up and removed at the extraction level from a grid of draw points. Ore is trammed to the ore passes by underground loader and dropped to a haulage level for transport by trucks to the gyratory crusher. From the crusher, the ore is conveyed to the mill via a 4.5 kilometre long conveyor system. Block caving was chosen for the New Afton deposit because the underground infrastructure could be built below the historical open pit of the Afton Mine (a previous operation of Teck Resources) and this method is favorable to large-scale low-cost mining.The New Afton deposit is a copper-gold, alkalic porphyry system. Hypogene mineralization is characterized by discontinuous copper sulphide veinlets and disseminations, principally chalcopyrite and minor bornite, along with pyrite as the second most dominant sulphide. Gold particles vary in size from 5 µm to 40 µm and occur as native gold and electrum, associated mostly with the chalcopyrite grains and never with the pyrite. In some instances, a second alteration phase has resulted in the copper sulphides being replaced by tennantite-tetrahedrite locally and along faults that transect the mineralized body. The design head grade of arsenic is 244 PPM, although the presence of tennantite is inconsistent and can vary from trace levels to 15% of the total copper. No arsenopyrite is present in the hypogene ores. Supergene mineralization, consisting of native copper with accessory chalcocite occurs in minor amounts along faults and highly oxidized near-surface portions of the deposit."

Jan 1, 2016

By P. Cielo

"Nondestructive inspection is an important quality control tool in the material processing industry. Being nondestructive, such a control may be applied to the whole production, as long as the available techniques are fast and easily automated. Ideally, nondestructive testing (NDT) methods should operate in a noncontact configuration in order to be deployable on-line with minimum perturbation of the production process.After a short introduction to the most common NDT techniques, with particular emphasis on ultrasonic, radiographic and electromagnetic methods, a few new approaches which are under development at the Industrial Materials Research Institute, (Boucherville, Quebec), are reviewed. Noncontact techniques such as laser ultrasound, thermoelastic and thermographic methodologies will be described, and their applications to materials of industrial interest will be discussed."

Jan 1, 1989

By R. L. Armstrong, C. I. Godwin, V. M. Kruan

"The Scheelite Dome tungsten-bearing skarn property, central Yukon Territory, is in metasediments in contact with a quartz monzonite intrusion. Contact metamorphism to biotite-muscovite- andalusite hornfels and calc-silicate hornfels is superimposed on low-grade regionally metamorphosed rocks represented by quartz-mica pelitic schist and muscovite-biotite pelitic schist.Metasediments are likely Precambrian in age, even though Rb-Sr whole-rock analyses indicate an early Paleozoic age (511±41 Ma); this apparently too young radiometric age is due to partial loss of radiogenic strontium during regional metamorphism. The minimum age of the quartz monzonite intrusion is Cretaceous at 90.4±2.6 Ma (K-Ar on biotite) and its initial 87Sr/86Sr ratio is 0.7121. The high initial ratio of the intrusion is due to the addition of radiogenic strontium from the metasedimentary country rocks and perhaps an underlying older basement.Scheelite-pyrrhotite-chalcopyrite mineralization occurs in diopside-zoisite skarn pods within the calc-silicate hornfels near the quartz monzonite intrusion. The source for lithophile tungsten is probably the same as for the granitic magma, namely Precambrian sialic basement.IntroductionThe Scheelite Dome tungsten skarn property is within the Mc-Questen map-area (NTS: 115P/16),28 km northwest of Mayo, Y.T., at latitude 63°47' north and longitude 136°15' west. The property can be reached by helicopter or by four-wheel- drive vehicle from Mayo.This paper summarizes the geology of the Scheelite Dome property, which has been described in a general way by Little (1959) and Cathro (1969). Geological mapping and sampling were done by the first author (nee Steffler) during June 1979. Field work was supplemented with detailed work at the Department of Geological Sciences of The University of British Columbia during 1979 and 1980 (Steffler, 1980). Whole-rock chemical analyses were done by Cominco Ltd."

Jan 1, 1982

By L. C. Galloway, P. M. Tiley

"Some progress has already been made in defining the parameters which will determine the performance of a guidance system in a mine shaft. Very little information is available, however, to help designers or operators predict the effects of varying these parameters in new or existing installations.The experience we have gained from monitoring a variety of installations has led to the development of a model which simulates the motion of a conveyance as it moves through a mineshaft, restrained by fixed guides.This paper presents a general analysis of the performance of the guidance system used in several installations, as well as a detailed description of the problem encountered at one mine and the steps taken to solve it.IntroductionOur company has investigated in some depth the problems that arise in the guidance of mine hoist conveyances.We have a telemetering accelerometer which we obtained to test mine hoist brakes. Frequently, during brake tests, the mine owners request us to use this instrument to measure the lateral motion of the conveyance ""to check guide alignment"". We have made such tests in shafts that have guide s of different kinds, including wooden guides, steel rail s and tubular steel guides. From these tests, we have gained some valuable information about guidance systems.In a well-aligned guidance system that is designed within common and well-known practice, the conveyance will experience very little shock most of the time. However, on rare occasions, shocks up to .5 g will occur. That is, the conveyance exerts a force of up to half its loaded weight on the guide. If the guide slips or is damaged by this force, it will be misaligned for future trips and become the cause of future shocks. In time, the whole guidance system can become misaligned."

Jan 1, 1982