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By H. C. Cooke

This paper will discuss two comparatively unrelated subjects; first, a general review of the advances made at the more important properties in the last year; and second, a statement of the conditions controlling the deposition of the copper ores in the Rouyn area, as determined by last summer's field work. FIRST PART Development has been very rapid since I stood before the Institute one year ago to discuss this same subject. Then, there were many properties on which gold had been discovered, any of which might develop into a mine. Further work has eliminated the most of them as possible mines, or at least has shown that before they can attain that status further discoveries must be made on them. Then, all gold veins held forth much the same promise; now the indications are that one particular type of gold vein is of greater prospective value than others. Then, all eyes were turned toward gold as the metal of prime economic importance; now copper has taken the centre of the stage, and gold is distinctly in the background.

Jan 1, 1926

By Martin P. O'Connell

"IT IS INDEED A PRIVILEGE to address a group representing a sector of the Canadian economy so important as is the mining sector. Important, not only today, but certainly of great importance for the future development of Canada, for employment, for our trade balance and indeed, when one looks at what we are calling increasingly an industrial strategy, for the future. Surely mining will have a very significant role to play in fulfilling that. It's of special interest to me, as the Minister of Labour - and I ought to confess at the very beginning that I am just two months into this function - of special interest for me to know that you are giving such attention to labour-management relations. I think it is timely that, from my point of view at least, you do this, because for the first time in twenty four years major revisions of the Canada Labour Code as it relates to industrial relations and disputes settlements are currently in the House of Commons going through their second reading, after an easier introduction and some changes which I would be very pleased to describe later this morning. It is very timely too, I think, that we should be looking at this area because public interest is certainly at a high level. It is not only at a high level but it expresses a good deal of irritation with the current status and procedures and results in collective bargaining and there is some urgent search for more sophisticated or modified procedures for settling differences in labour-management relations. The public wants different kinds of results. I think that is apparent to all of us. They want results in terms of justice and equity on both sides. And it means that a Minister of Labour and certainly governments who often are representing, or are the third party in discussions, have a very important and complex role to play in attempting to create a balance as these two parties come to contracts and come to agreements."

Jan 1, 1972

By Raymond B. Hryciuk

Environmental auditing has evolved rapidly over the last decade — first in North America, then Europe, and most recently in Asia — into a widely practiced discipline designed to provide senior management with assurance that operations are being managed in compliance with established governmental standards, internal company policies, and good industry practices. This paper first examines the evolution of environmental auditing, focusing in particular on three interlocking driving forces: company initiatives, collaborative industry initiatives, and government initiatives. Characteristics of effective audit programs, those that have emerged among the leaders, are discussed, including: objectives, scope, coverage, approach, staffing, and organizational considerations. The author then addresses important future trends and developments for environmental audit program design, content, and coverage.

Jan 1, 1996

By Greg Gosson, Larry B. Smith

"These are heady times for the mining industry, with strong metal prices, investor enthusiasm for the junior explorer and ready access to finance for mineral projects. Many projects were shelved in the past because of technical deficiencies — insufficient tonnes or grade, metallurgical problems, the deposit was too deep or too narrow, or the project was physically or economically under water. With the possibility of sustained metal prices, now is the time for those previously “challenged” projects to be re-evaluated and financing sought for continued development. The question is, do these deposits have reasonable prospects for economic extraction, as required by all mineral resource reporting codes? NI 43-101 defines a mineral resource as that portion of the mineral inventory that has reasonable prospects for economic extraction. However, a mineral resource is not simply an inventory of all blocks above a given cut-off grade. The spatial distribution and geological and grade continuity must also be considered. The qualified person (QP) must consider factors significant to project economics at the mineral resource estimation stage, and not just when qualifying mineral reserves. CIM Best Practice Guidelines for estimating mineral resources require the factors significant to project economics be current, reasonably developed and based on generally accepted industry practice and experience. In establishing the cut-off grade, it must realistically reflect the location, deposit scale, continuity, assumed mining method, metallurgical processes, costs and reasonable long-term metal prices appropriate for the deposit. Variations within the resource model (rock characteristics, metallurgy, mining methods, etc.) may necessitate more than one cut-off grade or economic limit in different parts of the deposit model. There must be sufficient knowledge of the metallurgical characteristics of the deposit, which should be supported by preliminary metallurgical test results."

Jan 1, 2003

By H. P. Whaley

This paper introduces Wabush Mines, including its ownership, physical assets, capacity, goals and achievements. It is to be followed by four papers which will present the detailed story. Wabush Mines, the largest supplier of iron ore to the Canadian steel industry, was brought into production in 1965. The ore is mined and concentrated in Wabush, Labrador, Newfoundland and pelletized at Pte. Noire, Quebec. Annual capacity is over 6,000,000 tons of high-grade iron ore pellets.

Jan 1, 1969

By D. J. McLaren

"Arctic Canada is one of the largest undeveloped terrains remaining in the world, and is in many ways unique. The ecological balance of the region is more delicate than tropical or temperate regions of similar size. This region is likely to be developed by research for and production of resources, primarily petroleum, in the immediate future. As well as sensitive terrain surface caused by permafrost in some areas, many large and small mammals and birds are also in a delicate balance with the environment. Small changes in this balance can have large effects.The probability of finding petroleum in different regions varies widely, but already there are good indications on the mainland and in the Islands that both oil and gas are present. Geophysical work in the offshore, particularly the Beaufort Sea, suggests further promising potential. Possible reserves in the Islands and mainland Arctic may amount to 50 or more billion barrels.A responsible approach to problems facing exploitation in an Arctic environment includes the careful monitoring by industry of likely effects of their activities. The Mackenzie Valley Pipeline Research Association test loop at Inuvik provides an example of such monitoring. Outside Canada, the operations at Prudhoe Bay on the north coast of Alaska show how major companies may operate responsibly and reduce environmental interference to a minim'.::at. Nevertheless, four variables must affect any decisions to be made concerning energy resource exploitation in the Arctic. These are man's need for energy, economic and industrial pressures to develop energy sources, the desire to preserve a deteriorating environment, and the role of government as representing all individuals in the country and their several points of view. Factors that must be taken into account in making any decisions include the importance of Canadian oil in a world picture, the need for alternative sources of energy in the near future, the depletion of nonrenewable resources at an accelerating rate and the increasing awareness that the major problems facing man have no direct technical solution and that social or political decisions must precede further techno-logical development."

Jan 1, 1971

By S. Kawai

Natural convective flow of the electrolyte solution plays an important role in several electrochemical systems. Copper refining electrolysis is the most important industrial process to produce high purity copper on large scale. Turbulent natural convection develops along vertical plane copper electrodes installed in an unstirred electrolyte accompanying with the electrochemical deposition and dissolution of copper during the electrolysis. It introduces the electrolyte stratification phenomenon. Thus, the electrolyte is circulated in a special way depending on each electrorefining tankhouse. The theoretical discussion is indispensable to understand the coupling phenomenon between the ionic mass transfer rate and the morphological variations of electrodeposited copper. In present study, the mass transfer rate of both Cu2+ and H+ ions as well as the momentum transfer rate is numerically analyzed accompanying with the turbulent natural convection along 1 m high Cu metal electrode surface.

Jan 1, 2007

By D. Royston

In SAG mills fed with a variety of ore types, hard packing between the shell lifters can come and go depending on rock type and rock size distribution and the presence of a binder. Packing can appear in all sizes of SAG mills, and can be tenacious. High ball impact forces (depending on ball size) in larger mills may compact and encourage packing. Packing can have a negative impact on milling performance and a change in shell liner design may be required to remove it. However shell liner design changes need to be managed with care to ensure liner reliability. In smaller mills control of packing can extend shell plate wear-life and may help to maintain milling performance in fixed-speed mills through the liner wear-cycle.

Jan 1, 2012

By Jack F. McQuat, Ross D. Lawrence

"Most geologists and mining engineers, in the course of their professional careers, frequently become involved with the appraisal of metalliferous mineral deposits and develop a familiarity with and standard approach to the evaluation of these deposits. When the same individuals approach the industrial mineral field, however, their usual approach pattern can be rudely disturbed.This paper highlights the difference in appraisal approach and outlines the factors common to both but which have entirely different emphasis. These comprise geological appraisal, analytical requirements, the importance of transportation, marketing requirements and standards, including appropriate allowances for product development, and marketing penetration.Out of these ""different"" considerations, however, a pat-tern or standard approach emerges which is as common to the industrial mineral field as that used either consciously or subconsciously in the metallic field.The paper reviews the different factors and points of emphasis and offers an outline of the common pattern of appraisal for industrial minerals."

Jan 1, 1971

By R. D. Lawrence

"Suggestions have been made that the appraisal of mining assets using discounted cash flow techniques should be based solely on proven and probable reserves in reliance upon the widespread international recognition of uniform resource definitions. Following a review of general accepted valuation principles, a survey of the literature and, most importantly, a review of real transactions in the open market, it is clear that valuators should not be constrained by the growing acceptance of modern mineral resource codes. On the contrary, valuation practitioners should be encouraged to examine all classes of mineralization and, after making due allowance for risk, to utilize all mineral resources as a basis for determining fair market value.INTRODUCTIONGreat strides have been made recently in achieving an international consensus on mineral reserve and resource definitions and classifications. The Australasian JORC code, the CIM code in Canada, the SME proposal in the United States and even a proposed code from the United Nations have all brought the objective within reach.Unfortunately, this success has led to another problem for mineral valuators. Certain securities regulators, tax collectors and their ilk have begun to expound on the opinion that discounted cash flow projections carried out to calculate net present values that would form the basis for a valuation determination should be based solely on proven and probable reserves. The author disagrees with this position. This paper examines the subject from four points of view:"

Jan 1, 2003

By C. R. Hocott

"IntroductionRESEARCH in petroleum production consists primarily in investigations related to the drilling for and recovery of oil. As an organized activity of individual oil companies, production research is now 30 to 35 years old, and the petroleum industry may point with justifiable pride to the achievements of this third of a •century. Emphasis on research has grown through the years until at the present time many of the larger companies operating in the United States •have well-organized production research staffs.In addition to the efforts of the oil companies, significant research and development in petroleum production technology have been performed by oilfield service companies and others. Valuable contributions have been made through fundamental research carried on by the U. S. Bureau of Mines and by various colleges and universities, both in their own programmes and in programmes sponsored by industry, such as those of the American Petroleum Institute. However, the total effort of these groups is small when compared to the sum of the effort devoted to research by the individual .oil companies. In contrast to some industries which conduct the major portion of their research through co-operative, sponsored research at universities or research institutions, research by the petroleum industry is done predominantly by individual company research staffs. These industrial research groups have usually been organized in such a way as to provide liaison and co-ordination with operating technical staffs. In this way, the research groups are kept aware of the major problems confronting the operating departments and, correspondingly, the operating technical people •are able to keep informed on research activity and progress. This type of close contact generally results in prompt testing of research developments in actual operations."

Jan 1, 1953

By Jared Onyirimba, Jim Viellenave, Hal Demuth, Dale Verran, Chad Sorba, Errol Lawrence, David Bronkhorst

As outlined within the Denison Mines Corp’s (“Denison”) Pre-Feasibility Study ("PFS") completed in late 2018, additional work is required to increase confidence and reduce risk associated with the application of the In-Situ Recovery (“ISR”) mining method at the Phoenix deposit, located on the Wheeler River Uranium Project (“Wheeler River” or the “Project”) in northern Saskatchewan. The successful application of ISR in any geological environment largely hinges on three fundamental requirements, 1) permeability (of the deposit), 2) containment (of the mining solution) and 3) leachability (of the mineralization). Denison has designed several staged technical programs to progressively reduce risk associated with these requirements as the Company advances the Project toward a Feasibility Study (“FS”) and Environmental Impact Assessment (“EIA”). This paper will discuss the scope and results of certain technical programs being undertaken as the Company aims to develop the first ISR mining operation in the Athabasca Basin.

Jan 1, 2020

By Les Philips

National Institute for Safety and Health?s (NIOSH, USA) Office of Mine Safety and Mine Safety and Health (OMSHR) has definitions for: -Proximity Detection as detection of personnel, vehicles and other objects near a machine using some type of sensor technology -Proximity Warning (aka Collision Warning) as detection of personnel, vehicles and other objects near a machine resulting in alarms that ?Warn the operator only ?Warn the operator and nearby personnel (two-way) -Collision Avoidance as the processing of sensor information resulting in control signals or actions that alter machine status/movement to avoid a collision by ?Computer control ?Human control

May 1, 2013

By Marketa D. Evans

The mining industry has a significant opportunity to capitalize on its past learnings in order to build better social relationships. The industry?s relationship with society is both critical and under pressure. Rising levels of public opposition and social conflict are already having material impacts on operations around the world. Industry has an opportunity to shape the future direction of this social engagement, build public trust and proactively respond to a material risk to operations, but first it needs to better understand the nature of the challenges and the urgency of addressing them.

Aug 1, 2013

By Fernando Canales

In the last decade a great dealt of attention has been paid to the chemistry of polynuclear gold derivatives with a central heteroatom, not only from the experimental and structural but also from the theoretical standpoint (1). Interesting hypercoordinated species of the type [C(AuPR3)5]+, [C(AuPR3)6]2+, [N(AuPR3)5]2+, [P(AuPR3)5]2+ and [P(AuPR3)6]3+ have been described (2), apart from other complexes with more conventional stoichiometry, and all have in common the presence of gold-gold interactions of ca. 3 Å. Usually, the chemistry of the first row elements of the p-block is known to follow classical rules of bonding, and only in cases of extreme electron-deficiency has the traditional electron count to be reconsidered to account for special types of molecular or solid state structures. Many of these heteroatomcentered complexes are electron-deficient and the gold-gold interactions provide a significant contribution to their stability. The attraction between these closed-shell systems has recently captured the attention in inorganic and organometallic chemistry (1). P. Pyykkö has summarized the available theoretical and experimental evidence of intra- and inter-molecular interactions between heavy metal atoms, such as Au(I) (3). In general, when heavy metals are involved in such interaction, the closed-shell attractions are of metallophilic or van der Waals type, as has been found for d8, d10 coinage-metals, and d10s2 centers. Experimental evidence for the aurophilic Au(I)???Au(I) attraction is available from crystallography, NMR and Raman spectroscopies, and optical spectroscopic measurements of the interaction strength (4). It is manifested in molecular conformations with relatively close Au???Au interactions of ca. 3 Å, whose strength has been estimated at ca. 25-50 kJ/mol (5). These attractions are weaker than most covalent or ionic bonds, but stronger than other van der Waals bonds and comparable in strength to typical hydrogen bonds. The phenomenon cannot be satisfactorily explained by classical theories such as hybridization (3). From a theoretical point of view, the attractions close to equilibrium distances are caused by dispersive interactions together with relativistic effects (6). The attractive contributions are dominated by pair-excitations from the heavy metal, such as gold, strengthened by relativistic effects. In all the cases where there are inter- or intramolecular metal-metal attractions, the correlation effects are essential; if they are omitted, at the Hartree-Fock (HF) level, repulsive interactions are obtained (6). Hence, it is necessary to use at least second-order Møller-Plesset level (MP2) methods for the dispersive forces, which are included in the electronic correlation effects (7).

Oct 1, 2003

By M. Jackman

"Froth stability is critically important for an effective separation of fine and ultrafine particles using column flotation. While a desirable froth stability is required to facilitate the drainage of entrained gangue particles for secondary cleaning, excessively stable froths could create problems in separation efficiency and down-stream processing. In this work, we demonstrate that a stable foam was produced using a poly (N-isopropylacrylamide) (PNIPAM) solution at the temperatures below the critical solution temperature. In contrast, very little foam was produced at the temperature above the critical solution temperature (~32 oC) of PNIPAM. We can also tune the foam stability by changing the temperature of wash water. When warm water of temperature of 50 oC was applied, the foam collapsed and diminished. This is probably attributed to the switching of PNIPAM molecules from coiled to a globule conformation as the temperature is increased. Our results indicate that the foamability and foam stability can be tuned by tempartureresponsive PNIPAM. This is the first time that thermo-responsive PNIPAM has been shown to have potential as a modifier of froth stability in column flotation.INTRODUCTIONIn mineral processing, column flotation has become a more prevalent process in the separation of fine mineral particles (typically < 100µm). Traditional flotation cells are sometimes less efficient in selective separation of ultra-fine particles (Kohmuench et al., 2009). The efficiency of flotation columns is dependent on the froth stability at the top of the cell to drain the unwanted gangue particles entrained in the froth. The greater froth height in flotation columns, compared to mechanical flotation cells, gives a longer froth residence time, allowing more of the drainage process to take place before the froth reports to the launderer. Secondary cleaning, by applying a wash water shower to the froth, enhances drainage of gangue particles entrained in the froth, and improves the recovery of the targeted minerals (Finch et al., 2007).While a stable froth is desirable to facilitate drainage of entrained gangue particles, greater amounts of fine particles have been found to contribute to excessively stable froths which could create problems for down-stream processes (Bethell et al., 2012). Operators have tried spraying additional wash water on the froth, and reducing frother dosage to destabilize the froth and to prevent backup at the launderer. The former is sometimes inefficient, and the latter results in unacceptable recovery loss. Currently, the best practice is often the installation of larger froth launderers, adding expensive defoaming agents, and/or using deaeration tanks (Bethell & Luttrell, 2005)."

Jan 1, 2016

The 14MW SAG mill at Tarkwa, Ghana, experienced a frozen drop charge incident on 10 February 2010. This caused downtime of 112 hours, a repair cost of $200k and production loss of 162,000 tons, corresponding to a loss of $8.9M. A new locked charge protection system was installed on the two Tarkwa mills on 30 July 2010, mitigating this risk. This system calculates the ore angle in real time while the mill is starting up and trips the mill if the ore angle exceeds a trip angle setting. The calculation of the ore angle is derived from the mill motor rotor currents only - no mechanical transducers are required. The head of Gold Fields West Africa, Peter Turner, says of the new system: "This is excellent work and the type of technology that has had and will continue to have, major opportunity cost impacts on our business."

Jan 1, 2012

By A. G. Roach

MILLING of Nova Scotia gold ores began in 1862 with arrastras and wooden stamps and has progressed to heavier stamps followed by tables and other forms of concentration for the recovery of the sulphides. Chlorination and cyanide leaching of the concentrates has been practised, and in 1936 the combined amalgamation and all-sliming cyanidation plant of Seal Harbor Gold Mines was built. It has since been found that it is not necessary to cyanide the full tonnage and now only the concentrates are being so treated. From his experience in this enterprise, the writer presents the accompanying flow-sheet and supporting comments. While he has not the temerity to maintain that it is the best or only flow-sheet for Nova Scotia gold ores, he feels that it warrants thoughtful consideration by members of the milling fraternity of the Province. THE ORE The gold in Nova Scotia ores occurs both free and intimately associated with sulphides-chiefly arsenopyrite. Much of the free gold is quite coarse and crystalline. This is especially true when it occurs in white quartz. When in the slate, it is usually in thin plates and scales, frequently coated and discoloured. The values bound up in the sulphides are not amenable to amalgamation and must be recovered by other methods-concentration, followed by smelting or fine grinding and cyanidation. While high freight and treatment charges apply on concentrates shipped from the Province to smelters, a considerable quantity has been so disposed of in the past. However, it is hoped that a customs cyanidation plant will soon become available to producers of these auriferous concentrates in Nova Scotia.

Jan 1, 1938

By A. Brown

"The mining industry is no exception to the general rule that continuing research is essential to good management; in fact, because of the imperfect state of knowledge in regard to many important factors associated with a mineral extraction, mining research assumes a position of unusual importance. On the basis of a recent visit to mining research centres in a number of European countries, the author describes their organization and their role in the mining industries of these countries. Some observations are made on Canadian mining research efforts, with a view to indicating a more systematic basis of procedure."

Jan 1, 1960

By M. Abdollahi, M. R. Khalesi, Y. Kianinia, A. Khodadadi Darban

High cyanide consumption during the processing of gold ores with high sulphide minerals can make the typical cyanidation uneconomic. Also cyanide is a toxic material and environmental concerns of cyanide compounds are serious. Optimization of cyanide consumption requires a methodology to estimate the amount of exposed cyanicides, the kinetic of their dissolution and estimation of formation of cyanide complexes which consume the free cyanide. In this paper, a methodology to estimate cyanide consumption by modeling the minerals and gold leaching kinetic based on a liberation model and speciation of all possible cyanide related species in the solution is presented. The results showed that this methodology could successfully estimate the cyanide consumption based on mineralogical data with very lower number of parameters compared to empirical models present in the literature, while it offers the prediction of formation of all cyanide complexes which could be used for optimization purposes.

Jan 1, 2017