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By Vlad Ruzicka

"Uranium deposits in the Rabbit Lake-Collins Bay area are associated with the sub-Athabasca unconformity which separates crystalline Archean or Aphebian basement rocks from Helikian clastic sedimentary rocks of the Athabasca Group. The basement rocks are a part of Wollaston lithostructural domain.Most of the high grade deposits, such as Collins Bay ‘A’ and 'B' Zones and Eagle Point are associated with altered rocks of the basal unit of the Wollaston Group. Some deposits, such as Raven and Horseshoe are confined to the uppermost unit of this Group. The Rabbit Lake deposit occurs in the middle, meta-arkose unit of the sequence. Locations of some deposits (Rabbit Lake, Collins Bay ‘A’ and 'B' Zones) are also controlled by thrust faults, such as Rabbit Lake Fault and Collins Bay Fault.The deposits contain either monometallic (uranium) mineralization (Rabbit Lake, Raven, Horseshoe) or polymetallic (mainly uranium-nickel) assemblages (Collins Bay “A’ and 'B' Zones).IntroductionThe Athabasca Basin region, a part of the Churchill Geological Province of the Canadian Shield, is composed of Archean and Aphebian crystalline basement and younger, Helikian, unmetamorphosed supracrustal rocks. The Rabbit Lake-Collins Bay area is situated at the eastern margin of the Athabasca Basin region, which hosts a substantial proportion of Canadian uranium resources.The crystalline basement complex was subdivided by Lewry and Sibbald (1979) into lithostructural domains and these domains were grouped into major crustal units designated, from northwest to southeast, as Western Craton, Cree Lake Mobile Zone, consisting of Wollaston, Mudjatic and Virgin River domains, and Rottenstone Complex (Fig. 1)."

Jan 1, 1986

By Cheryl L. Allen

The power required to operate a ventilation system can be 25% to 50% of the total energy requirements of a mine. In an effort to reduce energy consumption, initiatives are being introduced at Vale Inco to increase the efficiency of ventilation systems with the objective of decreasing energy usage. One energy conservation measure being introduced is the use of variable frequency drive (VFD) technology for fan motor control. Advancement in technology is making VFD applications more of a standard in industry. The benefits include improved operating performance and system control, reduction in current peak demand, and optimized power usage. This paper describes the application of VFDs for main and auxiliary mine fans; and associated potential energy savings.

May 1, 2009

By Shinji Muraishi, Shinji Kumai, Yasutaka Kedo, Takashi Kambe

"Magnetic pulse forming (MPF) is one of the extreme high-speed forming processes. A metal sheet which is accelerated by electromagnetic force is collided onto a mold and fine and sharp details of the product can be obtained. The deformation mechanism of the MPFed metal cannot be understood only by the microstructure observation of the deformed metal. The deformation behavior of the metal should be investigated also by considering the local microstructure change with strain, strain rate and temperature change during deformation. Numerical analysis is an effective method to achieve this requirement. In this study, pure Al and Cu sheets were deformed by MPF. Impact velocity of the metal sheet was calculated by using ANSYS Emag-Mechanical. Based on the obtained impact velocity, the deformation behavior of the metal sheet was reproduced, and local strain, strain rate, and temperature were analyzed by using ANSYS AUTODYN. The relationship between the local microstructure change of Al and Cu sheets and the deformation parameters was examined.INTRODUCTIONMagnetic pulse forming (MPF) is one of the high-speed forming processes using electromagnetic force. Fine and sharp details of the product can be obtained, and springback after deformation is extremely reduced in comparison to the conventional forming processes(Psyk, Risch, Kinsey, Tekkaya, & Kleiner, 2011). Figure 1 shows a schematic diagram of MPF. A metal sheet is placed over the coil in the discharge circuit. The discharge current runs through the coil, and magnetic fieldis producedaround the coil. An eddy current is inducedin the metal sheet. Interaction between magnetic field and eddy current creates electromagnetic force. The metal sheet accelerated by electromagnetic forcecollides ontothe mold. Forming is completed in a few tens of micro-seconds.MPF is suitable for metals with a high electrical conductivity like Al and Cu.The MPFed metal may have characteristic microstructure because of high strain rate deformation."

Jan 1, 2018

By D. MOORE, A. REINSBAKKEN, A. J. Sinclair

The Gypo quartz vein lies near Oliver, British Columbia, and was quarried between 1955 and 1968 for decorative chips. The vein is one of many quartz veins hosted by the Late Jurassic Oliver Plutonic Complex, specifically by the porphyritic quartz monzonite phase of the pluton. The vein has a known length of 155m and a thickness of 46m. It strikes east-west and dips at 60 degrees to the south. Mineralogy is predominantly quartz with minor pyrite, muscovite, fluorite, calcite, apatite and manganese; trace amounts of chalcopyrite, pyrrh otite, marcasite and molybdenite also are present. Quartz in the vein is zoned. A thin grey quartz zone found near the margins of the vein fades gradually into white quartz, which comprises over 95% of the vein. Late-stage boxworks cut earlier mineralization, particularly fluorite, which occurs as pods in a zone fairly close to the hanging wall. Sulphide minerals are found in a centrally located zone in the quartz vein. The hanging wall of the Gypo veins is altered only slightly, but thefootwall is altered extensively to a greisen of muscovite and grey quartz. Evidence suggests that early in rhe vein development, the adjoining country rock was feldspathized. As grey quartz and muscovite was deposited, a period of intensive greisenization and fracturing occurred which so weakened the rock that a central block of greisenized country rock foundered. This provided the open space in which the vein was deposited.

Jan 1, 1984

By J. Suarez

The innovation initiatives for world-class mines today and in the future focus on automation and robotics in equipment and machinery. These innovations have benefited from the development of advanced tools in global positioning, the Internet, the capabilities of data storage, transmission and handling, and intelligent systems. Forward-thinking companies have been investing in automated trains and trucks, selfdrilling rigs, intelligent flotation systems, etc. Considering that the emphasis has been mostly laid on improving the performance and reliability of the equipment and machinery, it is not surprising that the visibility was geared toward mechanical, electrical, process, and metallurgical engineering. One of the critical disciplines, mining engineering, has had less shine from the spotlight of automation and robotics. Mining engineering is concerned with the design, the operation, the management, and the reclamation of mines and mining facilities. In essence, it does benefit from the advantages of automation and robotics in equipment and machinery. However, being ?left out? in the innovation process may impede the core capabilities of this engineering discipline, which would create a two-tier knowledge and technology system in mines. For example, shovels in an open pit may be equipped with technology that can send real-time data of actual payload, number of buckets, mechanical status, etc. But, are mining engineers aware of the possibility to incorporate the data into their planning tools in order to have updated forecasts and accurate information? And if they are, are they equipped with the tools to reap the rewards of those technologies? And if so, is the personnel trained to use the tools efficiently? This paper is a contribution to the discussion on the technological advances in mining engineering. For the authors, the roadmap to the future requires a smart integration of technological advances in hardware and software so that mining engineers are not only aware of the possibilities, but also trained and capable of using the available tools. Essentially, this paper believes that automation and robotics in equipment alone will be undervalued and underutilized if the owners and drivers of the mining systems (i.e. the mining engineers) do not possess the tools and training to integrate the technological advances into the functions of mining engineering. The intent of the paper is to analyze the available technologies for the core mining engineering functions of design, planning, scheduling and optimization. The analysis will lead to discussions and suggested solutions on integrative technology solutions that would create optimum value for the mining processes and equipment technologies.

Aug 1, 2013

By Michael L. Wayman

Native copper is copper which exists in nature in elemental, metallic form, rather than being chemically combined as is the case with the more usual oxides, sulphides, carbonates, etc. Several other metals, including gold, silver and platinum also occur in native form as do, rarely, iron, lead and mercury; a few naturally occurring native metal alloys, notably electrum (gold-silver) and tumbaga {gold-copper or gold-silver-copper) are also known. An analysis of the relative availabilities of native metals as nuggets in a useful size range111 shows native copper to be by far the most abundant of the native metals, exceeding both gold and silver by at least two orders of magnitude. While such an estimate is crude, it serves to illustrate why copper was one of the first metals to have been used by ancient peoples. Native copper is known to occur on all inhabited continents, although its exact occurrence and abundance in ancient times cannot be unambiguously determined because many surface deposits may have been totally exploited and are therefore no longer identifiable. It is clear, however, that native copper does or did occur in all areas inhabited by the early metal-using cultures, for example in the Andes, in Central America and in the Near East. It is remarkable that most of the world's native copper occurs in the deposits of the Lake Superior region, primarily on the Keweenaw Peninsula of northern Michigan and on Isle Royale, an island in Lake Superior some 50 miles north of the Keweenaw deposits. Canadian deposits of native copper are found in Newfoundland and Labrador, Nova Scotia, Quebec, Ontario, British Columbia, the Yukon and the Northwest Territories (on Victoria Island, Bathurst Inlet and the Coppermine River area). It was to locate the latter deposits that the explorer Samuel Hearne was sent overland from Hudson's Bay in 1770; they were also surveyed by Sir John Franklin's expeditions in the 1820s.

Jan 1, 1999

By Bert Taylor

"The Mining concessions of Quemont Mining Corporation, Limited, are located at 48°16'N latitude, 79°00'W longitude, in Rouyn township, northwestern Quebec. Six hundred and forty acres in area, they lie directly north of, and contiguous to, the Horne mine of Noranda Mines Limited. The north arm of Osisko Lake covers a large area of the southern part of the property. The orebodies lie below the Jake with one body extending through to the bedrock surface.The property was staked in 1922, and was originally known as the Murray Claims. The group attracted interest from numerous exploration companies because of the proximity of the Noranda orebodies.The United Verde Extension Company, of Arizona, optioned the claims in 1926. They sank a shaft to a depth of 235 feet, at a short distance from the Noranda boundary. From a level established at a depth of 215 feet they completed 3000 feet of exploratory driving from which 6000 feet of diamond drilling was done. Only a small body of siliceous gold ore was found before they dropped their ·option.In 1928, The Mining Corporation of Canada purchased a 90 per cent interest in the property. An operating company, later named Quemont Mining Corporation, was formed. An electrical survey was carried out on a portion of the property, followed by deepening of the shaft to 922 feet. Levels were established at 500 and 900 feet, and 4,800 feet of driving and more than 3000 feet of diamond drilling were carried out from them.Geological knowledge at that time recognized that a major break, the Horne Creek fault, lay not far inside the south boundary. Striking north 80 degrees east, the fault dipped south at 85 degrees. The rock on the north side of the fault was massive rhyolite; to the south, meta-diabase and a little rhyolite. A left-handed movement was indicated by a 600-foot offset on a north striking diabase dyke. The small body of siliceous gold ore, referred to previously, was confined to the 215 level."

Jan 1, 1949

By M. S. Hedley

"The Lucky Jim mine is at Zincton in Slocan mmmg division; on the Kaslo-Nakusp branch of the Canadian Pacific railway. It is owned and operated by Zincton Mines; Limited; a subsidiary of Sheep Creek Gold Mines; Limited. The mine is far in the lead in the production of zinc in the Slocan. Its recorded production from concentrates and shipping ore was 102; 260; 191 pounds of zinc to the end of 1945.GENERAL GEOLOGY With the exception of acidic dykes the rocks near the Lucky Jim mine belong to the Slocan series, which is Triassic in age and consists principally of argillaceous rocks. It disconformably overlies greenstones of the Triassic Kaslo series about 3 miles to the northeast, and is cut by granitic rocks of the Nelson batholith 5 miles to the southeast.The sedimentary rocks in this area are best referred to on the whole as slates. They lie within the more fissile basal part of the Slocan series. The term 'slate belt' conveniently distinguishes this area of rocks characterized by slaty cleavage from the more massive argillites that are more characteristic of the Slocan as a whole. The contact between the slaty and massive argillites lies ½ mile southwest of the mine."

Jan 1, 1954

By C. Pawlik, R. T. Jones

Cobalt occurs together with copper in the southern African copper belt, and a large portion of this cobalt ends up in copper smelting slags, mostly dissolved in oxide form. It is possible to achieve high recoveries of cobalt by reductive smelting of the copper slags, using some form of carbon as a reducing agent in an electric furnace. For example, a 40 MW DC arc furnace was operated at Chambishi Metals in Zambia from 2001 to 2008, and demonstrated cobalt recoveries of around 80% from slag to an iron-rich alloy containing copper and cobalt. The alloy was atomized prior to leaching. With the recent increase in demand for cobalt (and the resulting high metal prices), there has been increasing interest in this process route. There is also an alternative hydrometallurgical process for recovering the valuable metals from the slag. The choice between these process options requires a trade-off between capital and operating cost and environmental acceptability. This paper examines the potential for cobalt recovery from slags, and outlines various process options. INTRODUCTION Cobalt has had a number of important uses in society since antiquity, and its principal use has changed dramatically over time. Since at least 2250 BC, cobalt-based pigments (cobalt blue) have been widely used to colour manufactured goods such as glass and pottery. Later, cobalt became known for its magnetic and wear-resistant properties and high-strength alloys, and most of the cobalt produced was consumed in the production of cobalt-based superalloys. The greatest recent growth in cobalt demand is due to it being essential to the rechargeable lithium-ion batteries used in consumer electronic devices and increasingly to drive electric vehicles. Cobalt is usually produced as a by-product of copper or nickel. The copper belt in the Democratic Republic of the Congo (DRC) and Zambia supplies most of the world's cobalt production. In 2018, the DRC was expected to produce 90 000 tons of the world total of 140 000 tons of cobalt (Shedd, 2019). This paper focuses on the southern African copper industry, and specifically the cobalt that is able to be produced as a co-product from this. A BRIEF HISTORY OF SOUTHERN AFRICAN COPPER SMELTING Copper deposits in South Africa have been documented since at least 1685, when the Cape governor, Simon van der Stel, ‘discovered’ the 'Copper Mountain' at Springbok. South Africa's first public commercial mining company (imaginatively called the 'South African Mining Company') was established in Cape Town in 1846, to exploit the rich copper resources that were believed to exist in Namaqualand.

Jan 1, 2019

By Derek H. C. Wilton

"The Cape Ray Fault Zone of southwestern Newfoundland contains two notable electrum/ base metal sulphide quartz vein lode occurrences hosted by two contrasting lithological units, viz. a graphite schist horizon and a granite. The two occurrences, although in proximity, are not in direct contact, but, based on geochronological, geochemical and isotopic evidence, they were apparently deposited from hydrothermal fluids generated as a vapour phase from the magmatic progenitor of the Windowglass Hill granite.This paper provides further evidence, from REE and background A u and Ag data, for the magmatic origin of the hydrothermal fluids. Wall rocks to the electrum-bearing quartz veins in both the schists and granite have experienced a LREE depletion probably due to leaching by Cl-bearing solutions. Gold and silver contents are typically low in all rock types but there is a slight elevation in gold concentrations in those units in contact with the Window glass Hill granite. The granite also has the relatively highest gold and silver contents of any unit in the region.IntroductionThis paper presents the evidence from rare earth element (REE) and gold/silver concentration data for the magmatic origin of hydrothermal fluids responsible for deposition of the Cape Ray electrum deposits of southwestern Newfoundland. The two deposits occur in the Cape Ray Fault Zone (Fig. I) within the Windsor Point Group and Window glass Hill granite. The larger occurrence is called the Main Shear Showing and consists of a deformed quartz vein horizon, which extends for - 6 km, within the late Devonian Windsor Point Group. This unit is an intermixed ignimbrite and mafic tuff sequence with associated schists (metasediments) and gabbros. The host rocks to the mineralized quartz veins are interleaved graphite, chlorite and sericite schists. Basal ignimbrites within the Windsor Point Group have been dated, by Rb/Sr isotopic methods, at 377 ±21 Ma (Wilton, 1983a). The basal ignimbrites also have enriched REE patterns, an elevated initial Sr ratio (0.709) and a peraluminous-siliceous nature which suggest they resulted from the partial melting of continental crust (Wilton, 1984)."

Jan 1, 1985

By S. Srinivasan, R. Coté

"India is undergoing a massive electrification program using local coal to provide fuel for thermal generating plants. The Rajmahal mine in northern Bihar is scheduled to produce coal at the rate of 10 million tonnes per year by the end ofa sixty six month contract with MET-CHEM Canada Inc. for mine development. In order to control maintenance performance and warehouse inventory MET-CHEM is installing some proven computer-controlled programs and will provide extensive training to ensure that the systems are properly used. The programs are Maintenance Planning and Control System (MPCS) and Materials Management System (MMS), both of which were developed and used by Quebec Cartier Mining Company at its iron ore mine in northern Quebec. In addition, a Predictive Maintenance Program (PMP) using vibration analysis will be introduced . This paper discusses the three systems.IntroductionIndia is currently undergoing a massive countrywide industrialization and electrification program. Most of the power will be supplied by coal-fired thermal electric plants.One of the mines being developed as part of the over-all program is the Rajmahal Open Cast Coal project in the Godda District of Bihar, approximately 270 km north , and slightly west of Calcutta.The project is based on an agreement signed in January, 1989 between two government organizations - Canadian Commercial Corporation (Ccq and Coal India Limited (CIL). MET-CHEM Canada Inc. (MET-CHEM), an international consulting engineering organization which has worked in India since 1976, is CCCs Canadian executing agency for the project. METCHEM was the engineer-constructor and mining associate for the development of the 7.5 mtpy Kudremukh Iron Ore Project. This US$430 million project was completed on schedule and under the original budget estimate. The Rajmahal deposit is the responsibility of Eastern Coalfields Limited (ECL), a subsidiary of CIL. The project is to produce coal at the rate of 10.5 million tonnes per year in 1994."

Jan 1, 1991

By G. Macfarlane

"In 1985, a crushing plant, located in the feed preparation area of Kidd Creek's copper smelter, was modified. The plant, which originally had treated only copper-bearing materials for the smeller, at a rate of 10 tonnes per hour, was expanded to 40 tonnes per hour capacity and modified to treat silica ores to meet the smelter’s flux requirement and also gold ores from the company's Hoyle Pond property. In the storage area adjacent to the crushing plant a 300 tonne per day gold mill was constructed.This paper outlines the construction and first year of operation of the crushing plant and gold mill with emphasis placed on the capital and operating advantages to be gained by utilizing an existing metallurgical infrastructure.IntroductionThe Kidd Creek Mines Ltd. copper-zinc-silver orebody is located 24 km north of Timmins, in Northern Ontario . Mining of this massive sulphide de posit commenced in 1966 and, in the ensuing years, a concentrator and zinc plant were constructed at the metallurgical complex, approximately 17 km by rail from the mine site . At this same site, in 1981, a copper smelter and refinery were commissioned. The smelter which utilizes the Mitsubishi smelting process for the continuous production of blister copper from copper concentrate, has been comprehensively described in previous papers.At the time of the smelter construction, a small (10 tonnes per hour) crushing plant was installed in the smelter's feed preparation area. This plant was used to treat the copper-bearing revert material produced by the smelter, and, apart from periods when slags and matte were produced through furnace drainage at the end of each operating campaign, it was generally under-utilized. This fact, together with the requirement to devise a more cost effective method of providing silica flux for the smelting operation, was the basic rationale for modifying and expanding and crushing plan t. At the same time, development at Kidd's Hoyle Pond orebody had progressed to such a stage that a gold mill of 300 tonnes per day was warranted."

Jan 1, 1988

By P. A. Verhey

"This paper describes a series of wear-resistant ceramic materials which have been successfully used in the mineral processing industry in Canada. Applications include use with metallic ores, coal, potash and asbestos, and in other processes where wear degradation is of major concern. The paper will also deal with considerations involving the selection of the different ceramic materials available. It will cover the installation of ceramic materials on support structures under varying process ' conditions, as well as the other physical and chemical factors which have to be taken into account.IntroductionIn the mineral processing industry, large volumes of ores tailings and other materials are handled. The abrasive nature of most of these materials results in extensive wear to both handling and processing equipment.Wear ratios versus cost, production losses due to down time and wear-resistant material suitability for a given application all demand particular attention when viewed against the need for increased efficiencies in existing processes. As a consequence, a very active continuous search for materials with improved wear resistance has been carried out for many years.In this search, starting about 20 years ago, dense ceramic materials were tested and evaluated in certain applications, notably in the iron ore and asbestos operations in Eastern Canada. As a result of substantially better performance both in continuous extended life and ultimate economics realized , wear-resistant ceramic applications developed progressively in many other processing applications, replacing traditionally used materials.In the vast majority of wear-resistant ceramic applications, considerable extended life over previously used materials was established. This invariably was not just a fractional increase but, in most cases , in factors of double, triple and often all the way up to 18 and 20 times the life of alternative materials used previously. In certain applications, extended life could not be measured and appears to be indefinite.Obviously, as a result of such experiences, the progressively wider use of wear-resistant ceramic materials is now an established trend."

Jan 1, 1981

By Leonard A. Wolff

"The 1980sfor the mining industry can be characterized as the survival of the fittest. High interest rates, low commodity prices, foreign subsidized competition and decreasing ore grades have contributed to a streamlining of the domestic mining industry in the United States, leading to the shutdown of operations or large cutback of work forces. The purpose of this paper is to look at the impact of a layoff on the employees of what was once a major uranium producer in south central Wyoming, twenty months after the final layoff and mine shutdown. INTRODUCTIONDecember 19, 1985, was the date of the final of three successive layoffs over a two-month period, leading to the complete shutdown of Petrotomics Company, a subsidiary of Getty Minerals Company. The final shutdown was due to a combination of depressed U3O8 prices and the takeover of Getty Oil Company by Texaco in January 1984.The layoffs affected 104 employees and included mine personnel, mill personnel and staff. Both hourly and salary workers were involved. The operation was considered non-union, however, a few mill hourly employees were unionized. At the completion of the layoffs. only a handful of employees remained for administrative and miscellaneous functions.For Getty employees, the terms of the merger agreement provided a generous level of separation benefits. The terms that were insisted upon by Mr. Petersen, Chairman of the Board for Getty Oil, stipulated that employees receive one month of severance pay, for each full calendar year of employment up to a maximum of two year's pay. This was the forerunner of what is now commonly known as the ""tin parachute”. All but the union employees of Petrotomics received these separation benefits. Union employees were covered by their separate, less generous, contract.Much of the literature that has been published in recent months has centred around the effects of layoffs on remaining employees, or the psychological effects on the severed employee. This study will emphasize the economic impact and ramifications due to a layoff, using the Petrotomics employees as a case example."

Jan 1, 1989

By Noel Billette, Jean-Luc Chouinard

"An analysis of the number of industrial injuries shows that the mining sector is particularly affected, since mining is one of the most dangerous industrial activities in Canada. This has led to numerous inquiries, and supports the need for an in-depth study aiming at the identification of factors responsible for these accidents. One possible factor often pointed at is the small crews incentives and this paper presents a scientific approach applied to check a potential link between bonus and accidents at two mining companies located in northwestern Quebec.The data required to do so were the accidents, the salaries and the number of hours worked at each mining site by the hourly paid personnel for the period from June 1979 to January 1982. The analysis of the results derived from the initial information shows different behaviours of the frequency rate vs the bonus rate at these mines. The number of days lost per accident is independent of the bonus rate at both mine sites, as shown by Khisquare tests on contingency tables.IntroductionA wide variety of opinions has been pinpointed by a survey of the literature related to individual or small crew incentives and industrial accidents in sectors of activity where it applies. In addition, various formulae of mining contracts take place in the industry on one part, and statistics from this sector indicate a high accident frequency rate on the other part. These fact s have lead to this scientific investigation which does isolate the direct impact of the bonus on workers' accidents. This study was undertaken with the full support of the Quebec Metal Mining Association.The conclusions of this preliminary phase of the researchproject are presented for two mining complexes in northwestern Quebec. The procedure is somewhat similar to the approach of the Belmoral Commission, with the underlying assumption that bonus has a direct impact on accidents."

Jan 1, 1986

By Todd S. Harris

"IntroductionThe western region of North America has long been considered a dynamic market supporting such diversified industries as lumber, agriculture, cement, and electronics. In recent years however, the region has also been the focus of a great deal of activity in the extender and filler mineral s business from companies seeking to position themselves to take advantage of the large demand for these materials both here and abroad.Extender and Filler MineralsExtender and filler mineral s include 15different products used in numerous end uses. The nine most important extenders and fillers are listed in Table I. These products range in price from under $50 a ton to over $4,000 a ton and basically represent the following three different types of minerals:Particulate products-Calcium carbonate; Kaolin; Silica.Platy minerals-Talc (Montana, Canada); Mica.Fibrous minerals-Talc (California, Eastern U.S .A.);Wollastonite.What distinguishes these products from other industrial minerals? For one thing, an important feature of extender and filler minerals is that they are used primarily in such consumer non-durable good s as paper, paint, plastics, sealants, and rubber which traditionally do not react as violently to swings in the economic cycle. In addition, these minerals are sold principally on key physical properties, usually brightness, particle size and shape, oil absorption, and hardness. As part of the physical minerals segment of industrial minerals, extenders and fillers are traditionally the most stable group and typically the most profitable. Studies by C.H. Kline over the past decade on extender and filler minerals has revealed historic average profitability (expressed as a percentage on sales) nearly double that of most other industrial mineral s.The demand for these minerals in the western region (Fig. 1), closely follow s the areas of greatest population concentration. These markets include pulp and paper, mainly in the Pacific Northwest, and paint, around Los Angeles and San Fran cisco. Other significant markets for extender and filler minerals in western North America include joint cements, carpet backing, and plastics, mainly PVC pipe."

Jan 1, 1986

By Wei Zhang, Jinhong Zhang

"The adsorption of ethyl xanthate on copper sulfides, i.e., chalcopyrite, chalcocite and bornite, has been studied in situ in aqueous solutions by applying an atomic force microscopy (AFM). AFM images show that xanthate, such as potassium ethyl xanthate (KEX), adsorbs strongly on chalcocite and bornite mainly in the form of insoluble metal xanthate, which binds strongly with the mineral surface without being removed by flushing with ethanol alcohol. This adsorption mechanism is totally different from the one obtained with chalcopyrite/xanthate system, during which oily dixanthogen is the main adsorption product on chalcopyrite surface. The findings obtained from the present AFM study suggest that an AFM image analysis is a powerful tool for the study of the collector’s adsorption on mineral surface and as well the development of novel collector for copper sulfide flotation.INTRODUCTIONIn mining industry, copper sulfide minerals, i.e., chalcopyrite, chalcocite and bornite, are usually separated selectively from non-valuable gangue by froth flotation, which treats the highest throughput and produces the maximum economic outcome of any surface chemistry process. In flotation, collectors are added into the pulp (mixture of water and fine-grained minerals) to selectively adsorb onto the target mineral and render its surface with high hydrophobicity, which is generally beneficial for a strong mineralbubble attachment and thus a high flotation recovery.The adsorption of collector on mineral surface, therefore, is vital for a successful flotation process and it has been studied by applying various surface analysis techniques, such as IR (Infrared Spectroscopy), CV (Cyclic Voltammetry) and XPS (X-ray Photoelectron Spectroscopy). (Poling, 1963; Allison et al., 1972; Mielczarski et al., 1984; Leppinen et al., 1989; Kartio et al., 1996) These studies have revealed a lot of information, such as the reaction, product and mechanism, of the adsorption of chemicals on mineral surface. It is also of great interest to directly get the image of adsorbed collectors on mineral surface changing with pulp chemistry, such as pH, redox potential, ionic strength and chemical’s dosage."

Jan 1, 2016

By Erwin L. Zodrow

"For 25 chemical elements in electrostatically precipitated fly ash (Lingan coal-fired power station), concentration changes are studied as a function of increasing proportions of fines (ash particle diameter less than 45 micrometres). Elements that are involved when concentrations increase as the proportions of fines increase are likely to escape into the atmosphere. These are Th, U, As, S, P, Sb, Na, Ag, Zn, Pb, Ni, Ba, Sc, AI, Mo (and Bi, Ge, Ga, F and Li), i.e., more or less highly volatilized elements. Of the less volatilized metals such as Fe, Ca, Cu, Ti, K, Co, Mn (and lanthanides), certain portions presumably also escape as stack emissions. Diadochy and spinel formation in bottom slag is presented as an emission-reducing agent for certain metals.IntroductionThe Lingan coal-fired power generation plant, owned and operated by the Nova Scotia Power Corporation, produces annually about 140,000 metric tons of ash (the residual mineral content after burning coal). The tonnage is based on a 15 per cent average ash content of Cape Breton coal.For purposes of this report, samples of the hard, fused slag (bottom slag) that is accumulated at bottoms of boilers, and electrostatically precipitated fly ash (ep ash), were collected and investigated. Bottom slag is a minor component of the produced ashes.The ashes were surveyed and the presence of over 75 major, minor and trace elements is reported. From this survey, 25 elements were selected to establish elemental enrichment/depletion trends when the proportions of the less than 45 micrometre <45µm) fractions in ep ashes increase. The results are significant in that, taking the case of elemental enrichment, the elements involved are likely to escape into the atmosphere, i.e, highly volatilized elements. Depletion trends for elements are presumably associated with less volatilized elements during coal-firing. Quantification of the emission of atmospheric pollutants is not considered part of this work. ""Igneous"" minerals generated during coal combustion include spinels (found mainly in the bottom slag), quartz, glass and mullite."

Jan 1, 1982

By Laurier Juteau

"NOT TOO LONG AGO, the CIM Education Committee saw the need for an information campaign to promote interest in mineral industry careers among young people. Today, times have changed and the Committee has now placed emphasis on the definition and function of the mining engineer. This situation, we believe, is entirely normal and the change of emphasis is not due to a change in the needs of the industry but more to a diversification of these needs. In years past, the Canadian mineral industry, although a very important part of our economy, was looked upon as a specialized craft and, because of the richness of our resources, did not suffer too much from competition. Now, times have changed and we are increasingly at the mercy of the competition and damaging inroads of price fluctuations, etc. We will therefore answer the questions raised in this discussion in the light of the role played in the past and the role to be played in the future by the Canadian mining engineer. We will begin with the following premises : (a) If mining engineers are to be involved in the massive problems of society, their traditional background is not sufficient. (b) Councils for professional development are working on criteria for the accreditation of advanced degree programs in the United States as well as in Canada, and, simultaneously, three-year technology programs are being developed along with professional engineering degree programs. (c) The difference between European and American industries regarding philosophy of life is that in Europe they appreciate wisdom more than HPs while in America the HP seems to be more important. The Engineering Digest of February 1972 reported that in the United States, during June and July of 1971, the second highest rate of unemployment was for the 55 to 64 age group ( 4.1 per cent). This survey certainly applies to Canadian industry as well. (d) Degrees to be awarded in Canadian universities and technical schools in 1972 will be:"

Jan 1, 1972

By A. R. Laplante

"In this paper, the performance of the Knelson Concentrator and of the batch and continuous Falcon Concentrators are compared. The units are based on different operating principles, and as such they perform quite differently. The Knelson yields very high free gold recoveries over a wide size range of both the recovered and rejected species. It is ineffective in recovering very fine ( <15 µm) or flaky gold, as encountered in flotation feeds, concentrates or tails. It is the: preferred unit for gold recovery from grinding circuits. The batch Falcon is effective in the fine range, typically less than 37 µm for gold. Its recovery zone is quickly saturated when there is significant heavies in the feed. It works best as a pre-concentration unit. The continuous Falcon is a versatile unit which is capable of recovering fine heavies (density down to 5 g/cm3 ), especially from coarser gangue. INTRODUCTIONThe purpose of this presentation is to describe the mode of operation of two Canadian centrifugal concentrators, the Knelson and Falcon. It is hoped that it will prove informative to prospective users in the selection, testing and optimization for applications of either machine. The work is based on testwork both in Canadian mills and at McGill. I am indebted to many colleagues at these locations. Appropriate references will be made to articles further describing the work, either already in the open literature or in preparation.Although this work is meant to be more practical than scholarly, it is appropriate to begin by considering how the two units achieve selective recovery. This will become useful in establishing a suitable testing methodology, which will then be described, and interpreting typical results. In the last section I will attempt to define appropriate applications for the two units. This is a thankless task, as I am likely to miss some applications or to make projections based on partial results, as much of the work is still in progress. In deference to the reader and both manufacturers, areas where reasonable doubt still remains will be identified."

Jan 1, 1993