Search Documents

By T. H. North, A. G. Glover, R. J. Pick

"Girth welding operations represent the rate-limiting step in pipeline construction. A joint industry-university program was set up to establish the field welding characteristics of large-diameter, high-strength line pipe.Theoretical work carried out at the University of Waterloo showed that pipe wall thickness and joint misalignment prior to welding has a marked influence on the lifting stresses acting on the root pass of girth welds. Pipe diameter and pipe ovality had negligible effects. Super-position of lifting and residual stress (caused by the fusion welding operation) highlighted regions of the weld bead most susceptible to hydrogen-induced cracking.The field welding characteristics of 1219-mm-diameter, 13.72-mm-wt Grade 483 line pipe were evaluated using a specially designed test rig. The principal test variables were lift height, delay time after root pass deposition, preheat temperature, pipe composition and joint misalignment prior to welding. For any given life, preheat and joint misalignment prior to welding had the most significant effect on cracking tendency.The output of this program has industrial significance and illustrates the beneficial features of university-industry collaboration.IntroductionField welding operations comprise the rate-limiting step during pipeline construction. Crack-free girth welds must be made in a wide range of weather conditions and consequently the field weldability of line pipe compositions directly affects pipeline integrity and construction economics.Pipe-laying practice comprises root bead deposition followed by a skidding operation involving lifting (or lowering) the pipe length onto skid s so that the next pipe length can be aligned prior to welding. Consider pipeline construction using 24.4-m lengths of 1219-mm-diameter , 13.72-mm-wt Grade 483 pipe weighing approximately 10,000 kg. Skidding involves loading a 3-mm-thick root bead by moving the free end of the pipe through vertical distances of up to 700 mm . The likelihood of cracking in these circumstances depends on the inherent crack susceptibility of the pipe composition employed, on the hydrogen content of the deposited weld metal and on how well the joint handles the external stressing caused byskidding."

Jan 1, 1981

By F. Kitzinger

Electromagnetic testing of wire rope has become more and more reliable over the past two decades. This improvement is partly a result of an unprecedented progress of electronic technology, which permitted the development of a new breed of testing instruments. There are two basic methods for the electromagnetic testing of wire ropes, the AC method and the DC method. Both methods rely on magnetic field disturbance caused by mechanical anomalies in the rope structure. The wire rope under test is passed through a magnetic excitation field, which can be a weak alternating field or a strong static field. Because the alternating field is produced by an alternating current, these instruments are of the AC type(l). In the early days of ND-testing, strong permanent magnets were not yet available; therefore, the static magnetic field was produced electromagnetically with direct current. Instruments based on static excitation are still called DC instruments(2), even though the field is now produced by a permanent magnet. Both these methods have certain characteristic features. The AC method can detect loss of metallic area caused by corrosion or other effects, whereas localized faults such as broken wires are better detected by the DC instruments . The basic principles of the wire rope testers have remained unchanged over the years and the improvements present in the new instruments usually reside in the signal processing and recording sections. The Instrumentation Department of the Noranda Research Centre* has been involved in a four-year development program which resulted in a new type of wire rope tester, the Magnographv** . This new instrument in many ways represents a considerable departure from the traditional wire rope testers. The Magnograph has already been patented in Canada and the U.S.A.(3), and patent applications are pending in other countries.

Jan 1, 1979

By S. Sopher, C. Barsotti

"Inco Gold Company was created in 1987 as an unincorporated business unit of Inco Limited. In 1988, Inco Gold Management Inc. was incorporated to supply management, exploration and engineering services to this unit. The first new project, at Casa Berardi, Quebec, was brought to production in September 1988, less than two years after completion of exploration. For 1989, Inco Gold's exploration and capital expenditures have been budgeted at approximately $94 million, a record level. Inco Gold holds interests in more than 80 precious metals ventures and prospects in Canada, the United States, Brazil, Indonesia, Papua New Guinea and France. The most advanced projects, in addition to Casa Berardi, are at Mineral Hill, Jardine, Montana, where initial production is anticipated in the third quarter of1989, and Crixas in central Brazil, where production is scheduled to begin during the fourth quarter of the same year.BackgroundTraditionally, Inco Limited's mineral exploration has concentrated on nickel and other base metals but since the early 1980s Inco's exploration activity has focussed strongly on precious metals, principally gold. As a result, three deposits have been discovered and developed . In order to accelerate the establishment of a strong gold mining enterprise with its own specific growth and profit objectives, Inco Gold Company was created in 1987 as an unincorporated business unit. At the end of 1988 Inco Gold's share of drill-indicated gold reserves was approximately 14 million short tons containing 3.4 million ounces of gold.At Casa Berardi in northwestern Quebec, one mine is in production and another is planned to open in 1990. Properties at Crixas in Brazil and at Jardine, Montana, U.S.A., were being readied for production in 1989. By 1991, Inco Gold's share of gold production is expected to be 125 000 ounces with a target of 400 000 ounces annually by the mid-1990s."

Jan 1, 1990

By Charles A. Schacht

"Relining, lining maintenance, and ladle repair can represent a significant cost in steelmaking. Therefore, the objective of all steelmaking shops is to minimize this cost and to maximize the lining life. However, the thermomechanical behaviour of the ladle lining is highly complicated and sometimes misunderstood. The ladle design also has a significant influence on lining life. Other factors which have a direct influence on lining life are the shop lining installation practices and manner in which the ladle is used. The objective of this paper is to provide an understanding of the impact of these factors as related to improving the integrity of the lining and increasing lining life.Fundamentals of Steelmaking Ladle Lining Expansion ForcesNumerous studies have been conducted by the author on steelmaking ladles with molten metal capacities ranging from 110 ton s to 350 tons. The steelmaking ladle typically has a sidewall plate with a slight taper and for analytical purposes can be classified as a cylindrical vessel.A typical ladle is described in Figure I. The ladle sidewall lining usually consists of a working lining and a safety lining. Although the type of refractory used in the working lining varies based on the type of steel produced and other metallurgical requirements, the refractories typically used are: 70% alumina brick; direct bond mag-chrome brick; resin bond dolomite brick; and direct bond dolomite brick. Fireclay brick, high alumina brick, or a similar strength brick is used as the safety lining.Normally, the ladle lining is exposed to a through-thickness temperature gradient and restrained by the ladle sidewall plate, is described in Figure 2. The hot face side of the refractory lining develops a compressive thermal force and the ladle sidewall plate develops an equilibrating tensile force. The radial joints open on the cold side of the working lining as the lining joints have little or no tensile strength. A radial compressive load (P) develops between the working lining and the vessel shell due to the thermal restraint imposed on the lining by the shell. The radial compressive load is transferred from the working lining through the safety lining onto the ladle sidewall. Therefore, the safety lining must have the strength to accommodate the radial compressive load (P)."

Jan 1, 1991

By Robert B. Parsons

"Thrashing one's way through a jungle of entangled tax rules is no easy task today, as Canada's legislators continue to complicate this country's income tax laws. At some magical point, there is presumably some balance to be struck between legislation which is equitable and unambiguous on the one hand, and at the same time is efficiently complied with and administered. It is becoming increasingly clear that the legislation is not in balance, and that there is a pressing need for some simplification of the income tax rules and regulations especially in areas of critical importance to the resource industries-even though such simplification will likely involve some sacrifice of equity and certainty.Introduction""I would wish that ... the superfluous and tedious statutes were brought into one sum together, and made more plain and short, to the intent that men might better understand them."" Edward VI, King of England 1547-1553.Regal decree notwithstanding, the legislation of most developed nations continues to become more complex, lengthy, and confusing than ever before. Canada's income tax system cannot escape the accusatory finger pointing at examples of this serious problem which plagues all of us today.Although many areas of our tax law could easily warrant some degree of simplification, for those who are involved with this country's resource sector, that horrendous, almost unreadable, part of our tax legislation which deals with resource taxation must be regarded s a prime candidate for simplification. In recent decades, but particularly in the past ten years since tax reform in 1972, budget after budget, both federal and provincial, have amended, massaged, modified, and manipulated the resource tax rules to the point where not only are taxpayers totally lost in their attempts to make some sense of the entanglement of rules, but also the draftsmen themselves acknowledge that the outer limits of complexity are being reached, and that the whole set of rules is on the verge of grinding to a groaning halt under its own weight of nonsense and frustration."

Jan 1, 1982

By Peter Harben

"This paper discusses the benefits of industrial minerals, their sources of supply, price and marketing trends, and their increasing use as substitute materials and ""strategic"" minerals. IntroductionKaolin finds have yet to spark the kind of frenzy associated with the 1849 California gold rush; no dolomite deposit has ever gained the notoriety of the Comstock Lode; and few industrial minerals are counted among the currently fashionable list of "" strategic mineral s"". Nevertheless, the glamorous zhine associated with metals may be somewhat superficial; further digging provides perhaps the real foundation of modern society - industrial minerals.They are often tagged as common, everyday materials that are simply dug out of the ground, crushed and hauled to a local point of consumption. Although this description is accurate in the case of road aggregates, sand and gravel, and the like, there are many exceptions to this rule. The term industrial minerals is rather nebulous, covering as it does the mundane and esoteric, the chemically active and the refractory, the $2 and the $10m-a-ton product. All of these minerals influence every facet of modern life from fertilizers to fire retardants, ceramics to cars, construction to clothes, and toothpaste to tennis courts. Their usefulness is well illustrated by the variety of industries they serve; the main ones are listed in Table 1. It is now time to dismiss the notion of non-metallics as the ""third world"" of natural resources business after the metallic and energy products by dispelling some of the myths regarding abundance, variety and value of the group's sixty-plus products."

Jan 1, 1982

By L. M. Ame, W. D. Harwood

"This paper outlines a management philosophy aimed at promoting employee involvement, quality and process improvement at Inco 's Thompson operations. It describes the use of statistical process control techniques, lessons learned and examples of progress.IntroductionThis paper provides an overview of the Manitoba Division's performance through the promotion of greater employee involvement, quality and process improvement. Having learned from other practitioners o f quality management, the Manitoba Division believes its experiences are applicable to all mining and other businesses.The Thompson operation consists of two underground mines, an open pit, a mill, a smelter and an electrolytic refinery. The workforce consists of 2000 members. The main products are electrolytic nickel slab and proprietary nickel rounds. Production levels are currently at capacity in response to heavy market demand.Paralleling much of the mining industry the corporation was faced with six years of decreasing nickel prices (Fig. I). Inco Limited survived by focusing on productivity and cost improvement. Manitoba Division productivity improved 32070 over three years beginning in 1982-the worst financial year in the company's history (Fig. 2). A real unit cost reduction of 20%, net of inflation, was also achieved (Fig . 3)."

Jan 1, 1990

By D. Crone, T. Watts

"The Lindsley project was a program of deep drilling to test the contact down-dip from two nickel-copper deposits, one uneconomical and the other mined out. The role of Borehole Pulse EM(PEM) was to detect the higher grade, more massive sulphide zones if they were missed by a drillhole, and to help determine geometry if the zones were intersected. Two problems appeared as the PEM survey progressed: (1) conductivity-thickness as measured by the PEM did not always relate to economic sulphides as determined by the market; (2) a pattern of unusual PEM anomalies was obtained that indicated something odd and big, but the cause was unknown. A large fold structure subsequently was indicated by a program of deepening previous holes, the third of which intersected high-grade mineralization below 1280 m. Falconbridge is in the process of shaft sinking and underground exploration.IntroductionThe Falconbridge Lindsley property is on the south rim of the Sudbury basin, 8 Ian north of downtown Sudbury. The original property was acquired by a prospector named James Stobie, who, in early August 1885, staked a showing that later became the Mount Nickel mine (Fig. I). On August 10 Stobie staked another property that would become the Little Stobie mine, and at the end of the same month he staked the main Stobie orebody.In 1888, the ground immediately west of the MOlU1t Nickel find was staked. This ground contained the Blezard deposit (Fig. 1) which was put into production in 1889 and was eventually acquired by Inco. Down-dip from the Blezard workings, on Falconbridge ground, is located the upper Lindsley No. 1 deposit which was drilled off by Falconbridge in the 1940s to 1950s. A decision to go underground on the Lindsley No.1 mineralization was made in 1969, but the project was cancelled in 1971 because of declining nickel prices. The shaft was stopped at 95 m, and the headframe and hoist were sold. Further surface exploration drilling in the 1970s discovered the deeper Lindsley No. 2 zone, but as it had grades similar to those of the No. 1 zone, it too was considered uneconomic."

Jan 1, 1992

By J. A. Bossert

"In 1957, the Department of Mines and Technical Surveys (now Energy, Mines and Resources Canada) issued their first certificate for a fire-resistant conveyor belt. The testing procedure used was a combination of those used in the U.S.A. and the U.K. Subsequently, certification was granted to fire resistant electric cables (1974), fire-resistant mine duct material (1976) and fire-resistant hydraulic fluids (1978).Until recently, the testing procedures were copied from either the U.S. or the U.K. However, since the founding of the new Canadian Standards Association (CSA) Steering Committee for Electrical/Mechanical Mine Safety in 1981, these requirements have come under the close scrutiny of new CSA technical committees who will attempt to adopt or change the existing procedures to meet Canadian needs. This paper outlines the existing test requirements and attempts to predict how they will appear after ""Canadianization"" by the CSA committees.IntroductionFires in underground mines have always been considered more serious than in other locations because of the confined space and limited atmosphere. A fire can make escape difficult or impossible if it is blocking all of the routes to the surface. Also, the products of combustion from an underground fire can asphyxiate anyone not having self-contained breathing apparatus.In an underground coal mine, the consequences of a fire can be even more serious because of the presence of methane and coal dust in the atmosphere (which can explode) and because the coal itself is combustible.For these reasons, the inspection authorities having jurisdiction over underground mine s in Canada are quite concerned about the flammability of any materials that are used in quantity in the underground environmentAs early as 1957, the Canadian Explosive Atmospheres Laboratory (CEAL) was asked to certify conveyor belting as fire-resistant. This is because many miles of this material are used in underground mines in Canada and, as it generally travels through the mine, it is a perfect vehicle for spreading a fire."

Jan 1, 1982

By Janne Karonen, Stephen Hughes, Mikael Jåfs, Jan Stål, Hannu Johto

End-of-life electrical and electronic scrap material attracts attention as a good opportunity for new value creation through efficient metal and energy recovery of such materials. On the other hand, the treatment of such wastes becomes important to avoid problems for society and environment. Treatment of such secondary raw materials faces multiple challenges due to their increasing complexity and evolving nature. Processing of these complex scrap materials together with recovery of a wide range of valuable metals with a combination of pyrometallurgy and hydrometallurgy using Outotec technology is discussed in this paper. One key consideration is environmental performance which needs attention when processing such complex secondary E-waste materials. Outotec has successful experience with commercial projects in the countries at the forefront of environmental and operational standards. INTRODUCTION Increasing attention has been drawn to the responsible processing of end of life Waste Electrical and Electronic Equipment (WEEE) as part of metals recycling, especially copper. It has been estimated that the amount of WEEE globally in 2016 was around the level of 46 Mtpa (Balde et al., 2017), representing a major disposal challenge but at the same time huge opportunity for resource recovery. The potential for increasing the recovery is high, because the official recycling rate of WEEE is in 2016 only 20% (Balde et al., 2017) and at the same time the estimated increase of the WEEE amount is between 3 and 5% per annum in the EU (Eurostat, 2019).

Jan 1, 2019

By Mark W. Masson, David B. Stevenson, David W. Broughton, Douglas R. Cruji, Steven E. Parry

"Abstract-The Amalgamated Kirkland gold deposit is located at Kirkland Lake, Ontario, within the Archean Abitibi Greenstone belt of the Canadian Shield. It lies on a fault or "break", termed the Cyprus Break, which is a splay off a regional structure termed the Cyprus-Battle Mountain Break. The Cyprus Break merges with the Cyprus - Battle Mountain Break above the -250 m level, as it was not encountered in shallow drilling or surface exploration. These structures lie 1.5 km south of the 727 000 kg (23 million ounce) Kirkland Lake Main Break and 0.5 km north of the 872 000 kg (30 million ounce) Larder Lake Break.The deposit is hosted by alkalic Timiskaming Group volcanic and sedimentary rocks which are overthrust by older Larder Lake Group tholeiitic and komatiitic flows along the Larder Lake Break. Timiskaming syenitic intrusives, similar to the host rocks for the Kirkland Lake Main Break gold deposit, intrude both suites.The Amalgamated Kirkland deposit consists of lode-style gold mineralization which is mainly hosted by altered and pyritized Timiskaming trachytic volcanics which wedge out or thin at depth, between two sedimentary units. The intersection of the Cyprus - Battle Mountain and Cyprus Breaks, in conjunction with the westward plunge of the volcanic wedge, appears to control the westerly plunge of the Amalgamated Kirkland deposit at approximately 50º.Mineralization is characterized by blue-gray brecciated and "wormy" quartz-ankerite veins which contain up to 10% fine-grained pyrite and, in decreasing order of abundance, minor galena, chalcopyrite, sphalerite, molybdenite and visible gold. The sulfides and gold commonly occur along fractures and wallrock inclusions within the veins. Native gold occurs as fine pinpoints distributed in 1-mm to 5-mm size clusters of up to ten or more grains.The auriferous veins occur within a quartz-ankerite-sericite-pyrite alteration assemblage which is enveloped by a broader zone of ankerite-sericite±hematite±quartz-pyrite alteration up to 60 m wide. This latter assemblage overprints the regional greenschist-facies chlorite-calcite assemblage.The Amalgamated Kirkland property has had a long history of exploration activity beginning with the first discovery of mineralization in 1911 on the Hunton Shaft claim located in the northeast corner of the property. Since that time various prospecting, mapping, trenching, geophysical surveys and diamond drilling programs have concentrated on either carbonate zones along the Larder Lake Break or quartz veins along the northern side of the property in association with complex trachyte flows and syenite dikes.Battle Mountain Canada Inc. located the Cyprus - Battle Mountain Break through a prospecting, trenching and geophysical program in 1989. Drilling by Battle Mountain and Cyprus Canada under the surface showing, coupled with several revisions to the structural interpretation of the Cyprus - Battle Mountain and Cyprus Breaks, resulted in delineation of the Amalgamated Kirkland deposit. Location of an auriferous structure through basic surface exploration within 1 km of a world-class orebody demonstrates both the subtle nature of Archean gold deposits and the potential for finding new mineralization in heavily prospected camps."

Jan 1, 1995

By Donald J. Farrish

"Mr. Chairman and fellow CMP members, most of these remarks will be made with particular reference to copper concentrate but the basics apply generally to other metal concentrates as well.For very good reasons, using copper as an example, smelting capacity usually is located either close to mine production or close to areas of high copper consumption. The mine producer can add on smelting capacity to insure that the copper in his concentrate can be processed into a marketable form under more or less controlled conditions including costs. On the other hand, the consumer wishing to assure a better supply of copper likewise can build smelting capacity and offer treatment charges attractive enough to discourage mines from investing in their own facilities. In this regard, freight is an important factor. Bulk shipments from the heart of Africa with a large overland component are uneconomic whereas concentrate movements from Australia or South America compare favourably with smaller metal shipments.A mine project which incorporates smelting capacity, will often, through the presence of this capacity, encourage active exploration and development of additional concentrate production in the vicinity. The usual result is that new mines within reasonable distance of the smelter will be able to avoid the capital required to build their own smelting and refining facilities and that the existing facilities will expand to appreciate economies of scale."

Jan 1, 1978

By A. McIntyre, L. R. Plitt

Both the Bond and the Hardgrove grindability tests are widely used in the mineral industry to measure the ease of the comminution displayed by a material. The Hardgrove test is mainly used for coals, whereas the Bond grindabifity test is mainly applied to hardrock minerals. The Bond grindability has the advantage that it can be empirically related to the energy required for comminution (work index), whereas the Hardgrove grindabifity test has the advantage of being easier to perform. In an effort to establish a valid correlation between work index and Hardgrove grindability, a series of parallel grindability tests were carried out on a wide variety of rocks and minerals. The standard Hardgrove test was modified to allow for materials with a higher density than coal. A new, satisfactory relationship was established which permits rapid estimation of work index from Hardgrove test data.

Jan 1, 1980

By R. Frank Chiappetta, E. B. Wilson

"The maintenance records for AL-60 airlegs at Falconbridge Ltd. are used to demonstrate some of the procedures for the analysis of such data.The data are not representative of pure failure s of one type or another. In fact, the records are for the undefined pseudo-failures which are usually found in industrial operations. However, because the machines are brought to the shop only when inoperative, the individual recorded components are treated as failures. Manual calculations are conducted to show the analysis of variance (ANO VA) approach to determine whether certain data can be combined; only a limited number of the 206 machines being considered. The manual procedures continue with the weighting of the suspensions; i.e. terminations f or reasons other than the failure of the given component. After the data are sequenced in the proper order, the nature or pattern of the data is determined using the Kolmogorov-Smirnov (KS) test.It is recognized that these manual examples must be replaced by compute r methods 10 process voluminous data of this nature. Such programs are developed and available. However, a program called RELCODE is used in this case to correspond to the manual examples and to take into account the suspensions. These analytical procedures form the basis for those studies required for good maintenance management."

Jan 1, 1985

By M. P. Brameld, R. H. McCorkell

"Overburden covering bedrock uranium deposits was sampled to depths of 29 m and Rn concentrations measured at the same depths. Total-alpha activities, V concentrations and Rn emanation (J) of the samples were measured. The U-flux into the overburden was greater in the past: oxidation and dissolution has since removed most U, leaving decay products which indicate the presence of U deposits when U itself does not. Distributions of U and decay products and their ratios to each other reflect U-migration and degrees of U-removal. Rn distribution in overburden is related to the J of overburden samples and the presence and movement of groundwater. Simple, rapid methods of total-alpha and J measurement are described.IntroductionThe overburden drilling apparatus developed by Bondar-Clegg and Company makes possible sampling and radon measurement in overburden from the surface down to about 50 metres. This apparatus was used here to study the diffusion of uranium and its decay products from ore deposits into over lying overburden at the N deposit of the Amok Ltd. property (Cluff Lake, Saskatchewan) and on the Imperial Minerals Ltd. property at Gooderham, Ontario. These ores are enclosed in bedrock; the overburdens were deposited by glaciers or streams. The migration of uranium and its decay products in such situations and the factors which affect it have been little studied in the past, as readily usable techniques for mapping it in three dimensions have not been available. The results reported here are somewhat sketchy and preliminary, but they indicate the value of the methods used and some of the patterns to be expected. Surface and subsurface sampling and measurements were carried out on 3-line grids crossing known zones of mineralization. The lines were 60 metres apart at Gooderham and 40 metres apart at Cluff Lake."

Jan 1, 1982

By C. A. Rowland

"Plant owners and operators, plant designers and grinding mill manufacturers are giving much attention to the design and manufacture of autogenous and semi-autogenous grinding mills, particularly the mills that have large diameters and draw power up to 10,000 hp and greater. Reliable designs giving long operating lives are required in today 's ore processing plants.This paper reviews bench-scale and pilot-plant testing to determine first if the ore is suitable .to be ground by these methods and then reviews the data obtained from pilot-plant testing that is used to select the mills and the grinding circuit. The paper then discusses the use of the pilot-plant results to design the mills. The most important pilot-plant data used for mill design are power and the amount of ball charge to be used. The mill size selected is a combination of these factors. Pilot-plant data not only establish power requirements, but can be used in the selection of the type of drive, variable speed or fixed speed, and the operating procedure to be followed. This leads into the mill control circuit to be used. The total charge in the mill, the type of drive and mill discharge arrangements are needed in the calculation of stresses and bearing loads. Conclusions reached from pilot-plant work are used to obtain data for process design, and autogenous and semiautogenous mill design should be part of any test program incorporating either or both of these grinding methods."

Jan 1, 1981

By Graham Popplewell

"Modular, predesigned diamond recovery plants have been a feature of the diamond mining industry for more than 20 years. The reasons for the selection of such a design route are contrasted with the alternative option of custom-designed route and the relative merits of the two approaches are discussed. The predesigned, modular plant is shown to be particularly applicable for the smaller operation, whether as part of a diverse alluvial mine, an auditing facility for an adjacent large plant, bulk sampling or a remote installation such as is envisaged in the Canadian diamond industry. The characteristics of the predesigned modular plant are described, as well as the inevitable compromises resulting from the concept. IntroductionThis paper explores the application of predesigned modular plants to the diamond mining industry and contrasts their features with the custom-designed installation .A predesigned modular plant is a self-contained unit, or a number of self-contained units, which, when assembled , make up a treatment facility. This is usually small scale in treatment capacity, although multiple modules may be used to increase over-all throughput.A move toward the use of such plants in the diamond mining industry resulted from the relatively unsophisticated nature of the design , the proven nature of pretested , standard plants and the low cost per tonne of capacity and their specific application in remote locations.The recovery of heavy minerals by dense medium separation (DMS) is intrinsically safe and more efficient than the older methods, such as jigs and rotary pans.All diamond recovery plants feature three distinct sections:• feed preparation• gravity separation, and• final recovery."

Jan 1, 1992

By Jean-Yve Tremblay, Michel Prud'homme

"Industrial minerals include a group of more than fifty minerals which are marketed into almost all the sectors of industry; they are the backbone of many manufacturing industries. Table I shows major end-uses for industrial minerals in manufacturing sectors. At Energy, Mines and Resources, industrial minerals are divided in three major categories: (I) agro chemicals and chemicals, (2) construction mineral s, and (3) ceramics and specialty minerals. A listing of the major groups of minerals is shown in Table 2. Agro-chemicals and chemicals are sold on the basis of their chemical content and purity. Construction minerals or structural minerals are distinguished by their performance as low cost and bulky commodities. Ceramics and specialty minerals are performance-specific and are sold for their property on imparting functions on end-products. Industrial minerals have unique characteristics that are useful in many stages of processing; from crushed size to micronized fillers a single mineral ca n serve a broad range of industries because of its intrinsic properties."

Jan 1, 1988

By A. J. Keen

"Cominco's Polaris Mine is an underground lead/zinc operation located on Little Cornwallis Island in the Canadian High Arctic. Polaris is the world's most northerly base metal mine, situated at about latitude 75°N and longitude 97°W (Fig. 1). The closest community is Resolute Bay about 100 km to the southeast.During the construction and development phase Cominco adopted a unique scheme to save time and money. Many facilities including concentrator, powerhouse, shops and warehouse were built on a barge in southern Canada. The barge was towed 4800 km to the site in August 1981. Production at Polaris began in November 1981. The current mining rate is 1 million tonnes per year. The mine employs 250 people with about 190 on site at any time.GeologyThe deposit is a Mississippi Valley type orebody and lies near the top of the Ordovician Thumb Mountain Formation. Ore minerals consist of sphalerite and galena with the gangue being predominantly dolomite with calcite and marcasite. The orebody is situated completely within permafrost, consequently the voids frequently found in the ore are filled with ice. The orebody strikes north-south, dips approximately twenty degrees to the east and takes up an area about 400 m wide by 700 m long. The upper portion of the orebody (60 m to 150 m below surface) lies in an area called the Panhandle Zone. The deeper portion of the orebody known as the Keel Zone extends to 300 m below surface (Fig. 2). The deposit is strongly zoned with a high grade zinc/lead and iron-rich tabular core overlain and underlain by vein, stringer and breccia mineralization. The ore reserves at January 1991 were 14.6 million tonnes at 3.6% Pb, 13.7% Zn, 3.2% Fe, after producing 8 million tonnes at 3.9% Pb and 14.2% Zn since November 1981"

Jan 1, 1992

By Jaime V. Ongpin

"The author will give a capsule history of Benguet Corporation and attempt to identify its operating environment and underlying ""strategy"" until 1974, when the company's management assumed office. The company's operating environment and ""interim strategy"" from 1975 to 1980 will be described. The discussion will cover an environmental forecast and define the company's"" strategy for survival"" for the balance of this century.IntroductionIn December last year, I was asked to deliver a pa per for the management lecture series a t the Asian Institute of Management in Manila. The paper was entitled "" The 1970's: A Decade of Disaster For New Mining Projects"" . In that paper, it was my task to review the results of new mining projects in the Philippines during the previous decade. The task was not a happy one, for the results themselves were not only unhappy, but disastrous on a scale unprecedented in Philippine history. Out of a total of 17 major mining project s involving an aggregate capital investment in excess o f US $2 billion during the 1970s, only three project s have been profitable, and all the rest have either gone "" belly up"" or are teetering on the very edge of financial disaster.It is in the context of this shocking record of widespread financial dislocation in the Philippine mining industry, (which in varying degrees appears to have been paralleled in virtually every other country in the world where mining is an important sector of the economy) that I address myself tonight to the theme of this symposium. My paper is entitled ""Risk Management Strategy in Mining"" and it is sub titled ""Can Benguet Corporation Survive to Celebrate its Centennial in 2003?"". I have inserted the word ""Strategy"" and added the subtitle, because I wish to make it clear first, that my presentation to you tonight will be focused exclusively on the strategic aspect s of risk management, and second that I will limit myself to Benguet's own ""in-house"" experience and perspectives on this subject. I would caution you therefore, to consider my views within this restricted framework, and in light of the particular and sometimes peculiar circumstances within which Benguet Corporation operates."

Jan 1, 1983