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By R. Carter, C. S. Samis

"SummaryThe results of this investigation indicate that the gold in the cyanide tailing of refractory gold cyanides is occluded in fused •particles formed during roasting. This conclusion was reached following microscopic examination of calcines produced at various furnace temperatures with different atmospheres, and a •comparison with calcines produced by decomposing samples of completely sulphated concentrate under conditions such that the maximum particle temperature varied between 6•50°C. and 1,100°C. This comparison showed that the particle temperature during a normal roast may be several hundred degrees higher than the furnace atmosphere, or that the fusion is associated with a low melting (950°C.) eutectic mixture of FeO and FeS.Because of the unavoidable particle fusion during a furnace roast, and because low particle temperatures are essential for gold extraction by cyanidation, aqueous medium oxidation under high oxygen pressures was studied. Gold recovery from calcines produced by this means was over 98 •per cent •compared with a maximum of 80 per cent from furnace calcines.IntroductionMANY arsenical gold ores are called 'refractory' because much ' of the gold cannot be satisfactorily extracted by cyaniding the raw ore or concentrate. Even when such ores are roasted to oxidize .the iron and arsenic and 'release' the gold, often 10 to 25 per cent of the gold present is lost in the cyanide residues."

Jan 1, 1952

By H. W. Manley

SULPHUR, like the minerals of coal, iron and petroleum, is one of the essential materials in our modern expanding industrial civilization. Before discussing the salient features of the production of sulphur from the Canadian sour gas, it seems appropriate to outline the historical past and probable future utilization of sulphur. The ancient Greek writer Homer spoke of its "pest-averting sulphur" and the "divine purifying fumigation". Ancient alchemists found sulphur to be a fascinating and baffling material. The discovery of gun powder in the year of 1250, and its application to the art of war a, century later, made sulphur an important commodity in the progress of mankind. The initial manufacture of sulphuric acid in the year of 1736 by the Englishman Joshua Ward, established the basis of a chemical industry that today utilizes 80 per cent of the consumption of elemental sulphur. Commercial production of the chemical soda ash ( N a2C03) discovered in 1787 by the famous Leblanc Process, in-creased international demand for the element sulphur and marks the birthday of the Sicilian sulphur industry.

Jan 1, 1961

By B. K. Gorain

Barrick' s Buzwagi copper-gold deposit in Tanzania comprises oxide, saprock and sulphide mineralized zones averaging approximately 0.058oz/t gold, 0.13% total copper and 0.03% cyanide-soluble copper. A comparative evaluation of the project based on two potential flowsheet alternatives is presented. The first flowsheet included a gravityconcentration and carbon-in-leach (CIL) plant. The second flowsheet was based on a Gravity-Flotation-CIL plant, which proved to be more economically robust. Selective flotation of copper minerals to produce a saleable copper concentrate proved to be challenging. Detailed characterization of the Buzwagi deposit was carried out through understanding of ore mineralogy, mineral liberation, floatability and selectivity, reagent chemistry and regrinding issues. With this insight, a flotation concentrate of greater than 25% Cu was achieved, recovering a significant amount of copper minerals and tellurides. The overall economics of the project improved significantly with the addition of flotation. Leach tests on gravity and flotation tailings showed an overall increase in gold recovery of approximately 6% for a Gravity-Flotation-CIL plant compared to that for a Gravity-CIL plant.

Jan 1, 2007

By D. G. E. Kerfoot

In September 1945, when the Lynn Lake nickel orebody was discovered Sherritt Gordon Mines was a small copper mining company with rapidly depleting ore reserves at its single producing mine at Sherridon in the Cold Lake area of Manitoba, 100 miles north of The Pas. The company has been formed in 1927, largely through the efforts of Eldon L. Brown, a 27-year old mining engineer, with the financial backing of Thayer and Halstead Lindsley and the Gordon family. The Lindsleys were American mine promoters who had been successful in the Sudbury area, and the Gordons had extensive interests in the lumber industry in northern Ontario. Carl Sherritt, who gave his name to the company, was an American trapper and prospector who had staked the copper property and sold his interest to the new company. Carl Sherritt died in a flying accident at The Pas in 1928. The Sherritt Gordon Mine started production in 1931, shipping copper concentrate to the new Hudson Bay copper smelter at Flin Flon, Manitoba. In 1931 the price of copper was 18¢/lb. Within a year the price had fallen to 5¢ /lb and the mine was forced to close. It remained closed through the Depression years.

Jan 1, 1999

By M. F. Goudge

Introduction It is only fitting on this occasion of the fiftieth anniversary of the incorporation of the Institute that we should indulge in a bit of retrospection and review the progress that has been made within this period in the various branches of the mining industry- progress that is so closely associated with the members of this Institute. Such a moment of retrospection will enable us better to appreciate the present status of the industry and to perceive more clearly the trends that should guide us in making sound plans for the future. The past half century has been a period of amazing industrial progress in Canada. In this period, the economy of our country has changed from one based chiefly on agriculture and the export of raw materials, to an economy based largely on a well integrated manufacturing industry. In all' o( these major developments, industrial minerals have played an important part and will play an increasingly, important part in the future. By ?industrial minerals? we mean the various non-metallic minerals (exclusive of fuels) as well as the rocks, sands, and clays used for industrial purposes. They are now used so widely and in such large quantities that modern industry could not function without them, and their continued availability at low cost is vital to the industrial future of Canada. The key position occupied by industrial minerals in modern Canadian industry was well illustrated two years ago when a strike occurred in the only Canadian plant producing soda-ash and calcium chloride at a time when those materials were already in short supply and unavailable from other sources. Within a short time of the shutdown of this plant, in which the two principal raw materials are limestone and salt, the great aluminium reduction plants on the Saguenay river were forced to curtail operations because of the lack of soda-ash, essential to the process of extracting aluminium from its ore. Automobile production, already harassed by a shortage of steel, was further hampered when glass for windshields and windows could not be supplied because the glass industry was slowed down almost to a standstill for want of soda-ash. Soap became almost unobtainable both to the housewife and to industrial users, because soda-ash is required in its manufacture. As a consequence of the soap shortage, the production o synthetic rubber at Sarnia was threatened because soap in large quantities is essential to the polymerization process. Motorists on gravelled highways all over Eastern Canada drove through clouds of dust because calcium chloride, used for dust laying, was not to be had. There were other cases of dislocation of industry related to the shutdown of this particular plant, but the above illustrates the wide ramifications of industrial minerals in modern industry. However, it is extremely doubtful if many Canadian citizens realized that these apparently unrelated happenings were connected in any way with limestone and salt.

Jan 1, 1948

By G. A. Vissac

In this paper we intend to deal particularly with the economic side of coal washing as it applies to our mines. We will then discuss why the dry-cleaning process has been selected, and give a brief description of our plant, dwelling only on its specific features and referring the reader to the numerous papers published on the subject for any details on the principles and machinery used in dry cleaning. ECONOMIC DISCUSSION The washery introduces an extra cost for depreciation, operation, and loss in treatment. A certain proportion of the coal, now being sold, and which the miners have been paid for. will have to be wasted. As a whole, the total increase in cost would be approximately 60 cents per ton. On the possibility of recovering this amount depends the success of the washery. There are two advantages to be expected from the washery, the first, which occurs at the mine and which will be certain; the second, more difficult to estimate, because it depends upon convincing our customers that they should pay more for a better product.

Jan 1, 1924

By R. Hammen, J. Lifton

"The purification of rare earth elements (REE) at mining operations is traditionally accomplished by multiple chemical phase-transfer processes including precipitation, solvent extraction, and ion exchange. We describe REE purification results with Solid Phase Extraction (SPE) columns that were developed to improve the speed and economy of REE purification. The SPE columns have the properties of enhanced equilibration kinetics, so that residence time of a few seconds will accomplish selective chemical transfers from solution phase to solid phase. We describe the separation of REE’s as a class from leach solutions and the further purification of REE salts. INTRODUCTIONHistorically the rare earths were first chemically separated from each other and purified by fractional crystallization. This slow, cumbersome, and laborious process was not suited to commercial production. Solvent Exchange (SX) technology was applied to the problem of separating and purifying the rare earth elements when it was determined in the late 1960s that there might be commercial uses for them individually. At the same time the very slow and expensive technique of ion exchange was applied either for ultra-purification of the desired “light” rare earths, or for the recovery and purification of the tiny amounts of higher atomic numbered, “heavy,” rare earths. Solvent Exchange (SX) has today become the standard for separating the rare earths across their atomic number spectrum. Whereas the separation of the light rare earths commercially may take 30 “cascades’ in a modern Chinese plant, the total separation of all of them from each other may take up to 80 such “cascades,” and is only even “practical’ with preconcentrated feed stocks, such as those produced in China by heap-leaching techniques performed in situ on very low grade radio-nuclide free ionic absorption clays.. Ultra-pure materials of all types are produced today by ion-exchange processing of ionic species already separated by solvent exchange.Hard rock deposits and refractory residues of tin mining and residues from uranium mining have been identified outside of China with very high ratios of dysprosium and other heavy rare earths to the majority lighter ones. Several issues face those who wish to process these materials so as to separate the heavy rare earths commercially:"

Jan 1, 2012

By M. Abdellatif

Successful demonstration of The Mintek Thermal Magnesium Process (MTMP) was achieved in November 2004 at the pilot-scale, About 30 tons of magnesium producing recipe was smelted in the DC arc furnace over a continuous operation of 8-days, Twenty-two furnace batching-tapping operations were carried out at a feed rate of 525kg/h and a smelting temperature of 1600-1700°C, The MgO content in the produced slag was as low as 6,7%, and averaged 9,2% MgO, resulting in an overall magnesium extraction of 77%, which reached 87% during good operating periods, Magnesium vapour was extracted at a rate of 70-85kg/h and was delivered to the condenser that was operated at 680-720°C, The magnesium was captured in the condenser crucible in a liquid state, allowing its prompt tapping, More than 3500kg of crude metal were produced over 15 on-line metal tapping operations, On average, a condensation efficiency of 85% was achieved during the entire testwork, which peaked at 87% during steady operations, The quality of the crude metal was similar to, if not better than, that of the Magnetherm's crude magnesium, A pre-feasibility study has indicated that the MTMP has the potential for lower capital and operating costs as compared to the electrolytic process, and therefore Mintek and its consortium partners are exploring opportunities for a commercial production facility.

Jan 1, 2006

By M. L. Connolly

Zinc production by Cominco Ltd. began in Trail in 1916 at a rate of 55 metric tonnes per day (t/d) and was increased ,in several increments until now electrowinning capacity approaches 750 t/d. The last increment, 40-t/d high-productivity electrowinning plant, was commissioned in 1974. In this paper, the design and operating experience with both the existing electrowinning plant and the new high-productivity plant are described.

Jan 1, 1977

By George E. Cole

Introduction In view of the fact that, during the past year, two Manitoba mines-Flin Fion and Sherritt Gordon-have entered the list of producers and have materially increased that Province's contribution to the metal production of the Dominion, it would seem appropriate at this time to review the progress of the industry in the Province, with particular reference to the out-standing metal-mining developments of the past decade. That these two mines have been able to continue their operations in spite of the low prices of copper and zinc adds a touch of brightness to the industrial life of the Province. Depression in metal prices is not encouraging to the mining industry, but it does stimulate efficiency in methods and costs of production. As two thriving towns have grown around the two mines, the will of the management to carry-on is of great consequence to Manitoba, this year so hard hit by the .agricultural depression. And, much as it is a pleasant feature in the mining situation that these mines have been able to continue operations, nevertheless it must be noted, in reviewing the mining developments of the past few years in Manitoba, that the Province was fortunate enough to profit by good times, in that an industry was established which gives evidence of permanency. In the metallic field, the section of Manitoba that first received attention from prospectors was the boundary district, west of the Lake of the Woods. Several claims were staked here at the time of the gold boom in the neighbouring Ontario area. But the first real interest in metalliferous deposits dates from the discovery of gold in March, 1911, in quartz veins on the shores of Rice lake, some twenty miles east of lake Winnipeg. Systematic and organized prospecting of the pre-Cambrian areas of the Province may be said to have commenced with that discovery. The first gold discovery in northern Manitoba was made at Wekusko (Herb) lake in 1914. This was followed by the discovery of the Flin Flan and Mandy copper ore-bodies in 1915 on Flin Fion and Schist lakes, respectively.

Jan 1, 1932

By H. L. Noblitt, Pauline Moyd, Louis Moyd

The deposit, which forms a ridge -adjacent to the York river, in Mont-eagle township, is held by Monteagle Minerals Limited, of Toronto. The ore is in a Precambrian gneiss which is composed of nepheline, scapolite, andesine and microcline feldspars, muscovite and biotite micas, and -corundum. The major orebody is tabular and is exposed for 1,200 feet along the crest of the ridge. It aver-ages about 90 feet in thickness, dips at about 70°, and was intersected by drilling at a vertical depth of 600 feet. The deposit was prospected for corundum in the early 1900's. Recent exploration was undertaken to deter-mine its potential as a source of high-alumina ceramic material, with by-product corundum and white mica. The program included prospecting, mapping, trenching, diamond drilling, bulk sampling, beneficiation research, a large-scale beneficiation test, product evaluation, market investigations, and plant design. Reserves, to a depth of about 300 feet, are estimated at about 3 million tons.

Jan 1, 1962

By Mosquera. J.

Tailings Storage Facilities (TSFs) are vast structures that respond to site-specific characteristics, rate of production, placement techniques, and the physical and mechanical properties of tailings. As a common denominator, TSFs are in some degree vulnerable to failure due to liquefaction, poor management, slope instability and/or unusual climatic events. In practice, stability of TSFS is determined by calculating a minimum Factor of Safety (FOS) using the Limit Equilibrium Method (LEM). However, it has been proven that relying exclusively on the limit equilibrium approach is not accurate because it is basically a static method that does not take into account the stress-strain distribution and displacement experienced by the constitutive materials of a TSF. In order to overcome these limitations of the LEM, the finite element method - Shear Reduction Technique (SRT) has been used as a more reliable tool for TSFs stability assessment. This paper presents a comparative stability analysis between an upstream tailings storage facility (UTSF), and a water retention tailings dam (WRTD) under static and pseudo-static states using simplified and rigorous LEMs and the SRT. Additionally, and taking into consideration the intrinsic uncertainty of tailings properties, sensitivity and probabilistic analyses in the form of Monte Carlo Simulation (MCS) and the Point Estimate Method (PEM) are applied to determine the Probability of Failure (Pf) and Reliability Index (ß) of each TSF. It is shown that the friction angle of UTSF?s foundation and the core?s cohesion of the WRTD are the main variables that govern stability. Further analysis shows that the WRTD has a higher reliability index and a lower probability of failure than the UTSF.

Aug 1, 2013

By W. N. Hamilton

Industrial minerals are plentiful in Alberta. Although exi ting in variety and in quantity, they constitute a minor segment of the province's mineral industry, which is based on oil and gas. In 1983 Alberta led all the other provinces in value of mineral production with a total of $22,2 18 million, 62 per cent of the total for Canada. Of Alberta's total, $22 million or about 3 per cent came from the indu trial minerals. Nearly two-third of this production is accounted for by sulphur, which is actually a by-product of the oil and ga industry. Alberta ranked third among the province in industrial minerals production for 1983, with about 20 per cent of the national total.

Jan 1, 1984

By E. J. Marcotte

"IntroductionDevelopments in the preparation, hydraulic transportation and placement of classified mill tailing as an effective backfill and support for mining excavations, have made feasible several advancements in mining methods that are safer and more economical. Hydraulic backfill systems have played an integral part in the development of more efficient cut-and-fill and blasthole stoping.The hydraulic transportation of tailing fill has made possible the elimination of expensive and laborious transportation, placement and spreading of gravel type fills. Also, in cut-andfill stopes, the use of hydraulically placed consolidated fill has largely eliminated the need to use extensive timbering for floors and supports, previously necessary when only gravel type, waste rock or unconsolidated tailing fill was used .Another important advantage of using mill tailing as backfill is that it decreases the need to contain a large portion of the mill solids waste in a surface disposal area and thus reduces environmental and ecological problems.Tailing Fill PropertiesConsolidated tailing fill consists of deslimed mill tailing and Portland cement. These two materials are mixed together in various proportions to form a high density slurry which is transferred underground by gravity through boreholes and pipelines. After placement underground, the water is drained off and the mixture is allowed to set. The strength of the consolidated fill is dependent on the cement content, particle size distribution and curing time. A typical tailing/ cement ratio used for bulk filling in stopes requiring vertical wall support is 30:1. Ratios ranging from 8:1 to 5: 1 are used for stope floors. High pulp densities minimize segregation and loss of cement during placement as well as reduce the amount of drainage water to be handled."

Jan 1, 1989

By J. Laganiere

A considerable part of the sulphuric acid requirements of the Aluminum Company of Canada's Arvida smelter comes from the burning of 180-200 tons per day of zinc '"'sulphide concentrates in a 22-ft.-diam-eter fluidized bed roaster. The plant and its operation were fully de-scribed in a publication that appeared about ten year ago (1). A simplified flowsheet of the roasting and gas-cleaning sections of the plant is given in Figure 1. The wet zinc sulphide concentrates are un-loaded into a pug mixer, by means of a Pay loader, and mixed with water in a mixing tank to make a slurry of 80 per cent solids. The slurry is transferred to a .feed tank and then introduced into the roaster at a point four feet above the constriction plate, which is the height of the settled bed of zinc calcines. The roasting temperature is con-

Jan 1, 1963

By Michael P. Davies

Mine waste facilities, and in particular tailings impoundments, are one of the highest risk aspects of any mining venture. There are far too many recent examples of how real and/or perceived physical or environmental impact from one of these facilities has had enormous economic impact on both the specific project and the overall parent mining company. In many cases, such dramatic impacts have followed a period where a due diligence of the mine had been carried out (e.g. in an acquisition, merger or similar) or an internal or otherwise audit had taken place. Consequently, it is suggested that there is a need for an audit/due diligence framework to assist those processes in terms of assessing mine waste facilities. This paper presents a recommended framework for completing either an audit or due diligence assessment of mine waste facilities under a number of typical scenarios. The framework will be of relevance to reviews carried out prior to mine construction, during operations and for mines that have been in a care and maintenance position and are to be re-opened. Concepts of risk management are introduced as an essential part of the recommended framework. The paper should be of value to current and prospective mine owners involved in stewarding an area of significant risk to viability of their mining venture. The paper should also interest prospective lenders to these ventures.

May 1, 2007

By Gordon Smith

ABSTRACT Gold-bearing quartz veins in the northeastern Ontario and north western Quebec mining camps are shown to have been mineralized in part by epithermal solutions. The vertical gradient of pressure during this stage of mineralization is calculated, using decrepitation temperatures of quartz and thermoelectric potentials of pyrite. The base of the Cobalt sediments, which lie uncomformably over part of the mining region, may be taken as datum level in calculating the depth of erosion into the basement below that level. The vertical extent of the epithermal gold mineralizaiton in this region is at least 9,000 feet below the datum level. INTRODUCTION IT WOULD have been difficult a few years ago to convince economic geologists that after making a series of measurements in a laboratory in Toronto, the depth of erosion which has taken place below the base of the Cobalt sediments at any place in the Ontario-Quebec mining region can be calculated to the neare.st 500 feet, or that the same series of measurements would also serve to allow a prediction of the minimum vertical depth of probable ore in a producing mine in the same region, with the same degree of certainty. Possibly it is just as difficult today, but the following description of the data and calculations may help to demonstrate the reliability of the method.

Jan 1, 1951

By Nader Golchinfar

The V-shaped breakout zones around excavation boundary have been captured by a variety of numerical methods such as FEM and DEM methods and failure criteria such as linear Mohr-Coulomb and non-linear Hoek-Brown failure criteria. Diederichs (2007) used Hoek-Brown parameters in his spalling parameter approach; however, it is convenient to use the Mohr-Coulomb failure criterion in numerical modeling because the material parameters can easily be determined from triaxial tests. It is shown in this study that when peak and residual strength parameters as well as dilation angle are properly defined, the brittle Mohr-Coulomb failure criterion can be used to model depth of failure near underground excavations satisfactorily.

Jun 1, 2012

By D. M. Ramsey

HIGH-INTENSITY magnetic separation as now practised in the commercial treatment of a large variety of industrial minerals is a com-paratively recent development, having had its practical beginning about ten years ago when it became necessary to devise more effective methods for the purification of the electric furnace abrasives and refractories-silicon carbide and fused aluminium oxide. The fundamentals of magnetic separation are, of course, very well under-stood; bur while very, very old in principle, the process has, in recent years, been developed to a point of far greater usefulness than heretofore. In fact, until the development of the high-intensity process,. magnetic separation was limited largely to the removal of tramp iron? with magnetic pulleys and the removal of the very highly magnetic portions of industrial minerals by means of horizontal conveyor-belt-type separators. All magnetic separation processes depend for their success on the fact that various materials are kinetically influenced to a greater or lesser degree by the force that we speak of as 'magnetism'. We have now come to regard 'magnetic separation' and 'high-intensity magnetic separation' as two different and distinct methods. However, both depend upon the reaction of a particle when placed in a magnetic field. The common types of magnetic separators quite generally operate on the principle that a magnetic particle can be lifted by a powerful magnetic force from a stream of material moving on a belt or other type of conveyor. The application of the force removing magnetic material by this scheme is directly opposed to the force of gravity and is, therefore, limited to sub-stances of a relatively high order of magnetic susceptibility, such as metallic iron and magnetite. Until a few years ago, one very important principle was almost entirely overlooked. Practically every substance is susceptible to some extent, at least, to magnetic attraction, and by the application of a magnetic force great enough, and properly applied, separations of materials heretofore considered 'non-magnetic' can be accomplished.

Jan 1, 1937

By William Ferguson, Claude Deveau, Wade Hazel, Stephen R. Young, Allen Lussier, Robert Copeland

"LocationSometimes known as the Bernie Lake mine, the mine is located about 180 km east-northeast of Winnipeg on the northwestern shore of Bernie Lake, close to the Nopiming Provincial Park and the Manitoba-Ontario boundary. The mine is accessed from Lac du Bonnet which is linked to the provincial road system.Brief Description of OperationTantalum Mining Corporation of Canada Ltd. operates an underground mine employing ramp access, room and pillar mining, and shaft hoisting for the production of tantalum, lithium and cesium minerals. Daily campaigned crushing of the tantalum and lithium ores supply separate concentration circuits. Tantalum recovery employs conventional gravity equipment together with recently developed centrifugal concentration methods. All tantalum concentrates go to Cabot Performance Materials for the production of tantalum chemicals and metal. Lithium minerals are recovered using heavy medium separation and silicate flotation to produce spodumene and montebrasite/amblygonite concentrates. The lithium concentrates are shipped worldwide for use in ceramics, specialty glass and mold powders. Cesium processing involves the dry grinding of pollucite as feed stock for the recently built on-site chemical plant dedicated to tl1e production of cesium formate, a high-density drilling fluid for use in the oil industry."

Jan 1, 2000