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By Stuart J. Schofield

Introduction The study of the ore deposits of British Columbia is one of fascinating interest not only from a scientific but also from a commercial standpoint and certain wide problems in connection therewith have interested me for some years. Several of these problems have been set forth in papers presented before this Institute on previous occasions. In 1918 it was pointed out that the commercial ore deposits of British Columbia, with one exception, were associated with the granodiorite batholiths of upper Jurassic age. This was followed, in 1922, by a discussion of the ore deposits of British Columbia in which the mineral belts of the province were defined and named, showing a zonal arrangement of ores in which the Pacific coast deposits are characterized by the presence of copper, while the interior belt is marked by the presence of silver, lead, and gold. Methods Of Investigation In reading various reports on the economic geology of British Columbia one is struck with the fact that the mineral veins may be arranged as a system and further examination will show that such a system follows two main directions, one northeasterly and the other northwesterly, both related in origin to the same force.

Jan 1, 1925

By P. Roman, L. Daneshmend

"During the last decade, mining companies have been overwhelmed by technological solutions to perceived problems. This is particularly true with information technology where rapid advances have resulted in a professional climate characterized by technomania — the perception that failure to adopt emerging technologies will result in a loss of competitive advantage. This paper describes the applicability of structured analysis and design techniques as an appropriate methodology for integrating emerging technologies in the mining industry. The potential of this approach to improve overall mine effectiveness through improved communication and co-ordination between operations and maintenance is discussed. IntroductionA strong working relationship between the operations and maintenance departments in both open pit and underground mines is fundamental to the overall success of the mining endeavour. Unfortunately, for many mines, this characterization is far from accurate. Short-range production targets dominate the day-to-day management of the mines. This can be seen in Bostwick and Buchanan’s (1993) report on American Barrick Resources efforts to achieve an aggressive 415 000 tpd mining program at their Goldstrike operation in Nevada. When production managers do not meet their quotas, the finger is often pointed at maintenance. As a result, a confrontational culture can develop between the two organizations, resulting in a lack of cooperation that exacerbates the problem. Historically, production planning has taken priority over maintenance planning. This is reasonable since production is the primary purpose of the mine with maintenance serving in a support role. This basic relationship remains intact today. However, the trends toward mechanization, increasing levels of automation, and larger equipment, have resulted in increased reliance on the equipment used in the mine. As a result, downtime costs now go well beyond the direct labour associated with the repair of the machine. Lost production costs due to downtime resulting from failed equipment are becoming an increasingly important factor in determining a mine’s overall economic performance."

Jan 1, 2001

By Ian S. Thompson

"Exploration properties form a continuum from grass roots to those with favourable geology, geochemical and/or geophysical anomalies, mineralization, showings (prospects), and finally to those with defined mineral deposits. Often properties exhibit a composite of these categories.The most problematic to value are properties or deposits that are not economically exploitable at the time of the valuation, due to a lack of exploration, insufficient grade or tonnage, poor mining conditions, or the imposition of socioeconomic, environmental, or legal constraints.Various acceptable methods of valuing the range of all such mineral properties or deposits are reviewed. Some inappropriate methods are also discussed.BIOGRAPHYIan S. Thompson is President and Principal of Derry, Michener, Booth & Wahl Consultants Ltd. (DMBW), an independent consulting practice, specializing in exploration, ore reserve estimations, engineering and valuations of mineral properties.Mr. Thompson is a graduate in Honours Geological Sciences from the University of Toronto with over 35 years Canadian and International experience in mineral exploration and development, including the discovery of base metal. gold and uranium deposits.DMBW is affiliated with DMBW, Inc. in Colorado, and works with independent engineering and financial groups in North America, Europe, Australia and Africa.Mr. Thompson is a national member of CIM; the Associations of Professional Engineers of Ontario and British Columbia; The Geological Association of Canada; The Society of Economic Geologists; The Prospectors and Developers Association of Canada and the BC and Yukon Chamber of Mines.INTRODUCTIONThis paper is presented in response to the request of the Mineral Economics Society of the Canadian Institute of Mining and Metallurgy for a Review of Approaches to Valuation of Mineral Properties, as recommended by the TSE/OSC Mining Standards Task Force.Exploration properties with undeveloped mineral resources range from grassroots acreage without exploration history, to those containing mineralization (or a mineral resource) that is insufficiently explored, to well explored deposits which lack either continuity, or sufficient grade/tonnage, or have poor mineability or metallurgy, such that they are not currently exploitable at the time of the valuation. This does not imply that they do not have value."

Jan 1, 2003

By J. D. Bateman

Introduction The lifting of restrictions on the development of radioactive mineral deposits by private individuals has re-opened the search for uranium in Canada to a large body of professionally trained prospectors. The entry of private capital and experienced prospecting techniques into the search for radioactive minerals has been enormously stimulated by the atomic developments of the past several years; and we can now look forward to the discovery of new productive sources of uranium. The rate of new discoveries will, how ?ever, depend on the effectiveness of the methods used. The large number of new pitchblende occurrences reported within the past several months is largely a measure of the energy with which the portable Geiger-Müller counter has been applied in the field. The counter is simply a 'radio' receiver tuned to one of the products of spontaneous atomic disintegration that is characteristic of all radioactive materials. Its effective use depends largely on how it is applied under the various geological and topographical conditions that ma y be encountered, and also on an understanding of its limitations. Extensive geological information relating to the occurrence of radioactive minerals in Canada has been accumulated during the past several years, and it is now possible to define in a general way many of the geological formations in which pitchblende and related minerals are likely to occur. Furthermore, prospecting can be localized in those parts of the favourable formations that offer the greater promise of containing commercial deposits. In this selection, the Geiger counter is the most useful tool available to the prospector for the actual detection of radioactive materials. As an example, an area of two square miles in the Northwest Territories, within which about a dozen pitchblende occurrences had been found over a several year period by conventional prospecting methods, yielded more than forty-five additional discoveries by application of the Geiger counter. Yet earlier attempts at prospecting this area with the counter had failed, due largely to faulty instruments and lack of experience in field application. The limitations of the counter are very considerable; but, when they are recognized, there is no more useful tool for the discovery of radioactive ores. It was not until 1944 that a practicable portable counter was developed, and then only by co-operation in the field by geologists and physicists. Officers of the Geological Survey of Canada working with physicists of the National Research Council brought about the development of the modern counter.

Jan 1, 1949

By D. V. Ziehlke, J. M. Franklin, T. M. Gordon, A. G. Galley

The Snow Lake-Wekusko Lake region of northern Manitoba conta ins numerous lode gold occurrences, including the largest gold deposit in the Churchill Prov ince, the Nor Acme mine. The Aphebian volcanic and sedimentary rocks of this region are comprised of submarine volcanic strata, overlain by turbidites, both of the Amisk Group, and fluvi atile sedimenta ry strata and bimodally composed subaerial volcanic rocks of the overlying Missi Group. Gold occurs as: 1) accessory gold in volcanogenic massive sulphide deposits, 2) lode gold in shear zones related to sy n- to post-FI thrust fa ults, and 3) lode-gold associated with post-F2 fault . An alteration a emblage of biotite, al bite and calc ite is associated with both groups of lode-gold deposits, and has been superimposed on the regionall y-developed metamorphic assemblages. AJthough these deposi ts are spatial ly related to britt le-ductile faul ts of different initial ages, they appear to have all fo rmed after the major period of reg ional fo lding and metamorphism, and thus may be penecontemporaneous. The alteration is different from the sericite-ankerite-quartz assemblage that is typically associated with gold deposits in Superio r Prov ince. Deposits in thi s area of Churchill Prov ince may have formed either at a higher temperature or a deeper structu ra l level than tho e in Superior Prov ince.

Jan 1, 1986

By C. V. Deutsch, O. Babak, J. G. Manchuk

High levels of geological heterogeneity occurring over relatively short distances pose a challenge to the unconventional open-pit techniques used in oil sands mining. There is strong motivation to mine selectively and minimize dilution and loss; however, the large equipment and high mining rate used to meet production targets tend to reduce selectivity. A numerical model is developed to account for geological complexity, mining equipment, regulatory criteria, and other operational parameters. This framework is used for more accurate forecasts, optimization of equipment, and other operational decisions. An example demonstrates the approach in light of Alberta Energy Regulator criteria.

Jan 1, 2014

By M. S. Badollet

Introduction Very little fundamental research has been done on asbestos fibre to cake maximum advantage of its properties and to determine in what commercial products it can best be utilized. For the research chemist who is associated with asbestos development work, a thorough study of mineralogical information on asbestos deposits would furnish reliable information on the rock formations and the mineral impurities closely associated with the asbestos. Furthermore, ?he must have an intimate knowledge of the uses of the fibre in various products so that he can visualize the importance of the fibre and the role it plays in industry. Some of the properties of asbestos fibres such as strength, composition, length, harshness or softness, and mineral associates are of considerable importance to the manufacturer because they are responsible for many production difficulties. Fibre Strength It has been known for some time chat asbestos filaments have considerable tensile strength. These strengths have been referred to merely as 'weak' to 'very strong'. Not until recently have numerical values been applied to the strengths of asbestos fibres. But today we can take a thin fibre filament and mount it between two holders and apply a gradually increasing load or pull until the fibre breaks. By measuring the cross sectional area of the filament and the amount of load applied, we can calculate the tensile strength of the fibre in terms of pounds per square inch. This type of test is slow and rather difficult, but the fundamental data obtained furnish important basic information that can be applied to mechanical processing equipment and to certain asbestos products.

Jan 1, 1948

By A. C. Hnatyshyn

INTRODUCTION THOSE concerned with coal mining operations in Alberta have been asked repeatedly the same question, "Why is mechanization in Alberta proceeding so slowly as to lag far behind the mines in the United States?" This question is often asked in such a manner as to indicate that a severe reprimand is overdue to the mining engineers of this Province for their apparent indifference to the problem of improving their mining operations by increased mechanization. To the average person, unacquainted with mining conditions and problems, mechanization appears to be simply a matter of introducing equipment to load coal underground and, once this is done, substantial economies in operating costs will automatically follow. Invariably, those who have followed this simple reasoning have found, to their regret, that such is not the case and that effective mechanization involves something more than the mere process of introducing loading equipment into a mine. To be effective, any programme of mechanization must take into consideration all operations incidental to the mining, transportation, and handling of the coal from the working face to the tipple, and must utilize equipment which can be best adapted to any peculiar condition or circumstance prevailing in the mine concerned. In the use of such equipment, the net and final result should be an improvement in operating costs of sufficient magnitude to at least return to the operator, over a specific period of years or during the expected life of that equipment, all his investment plus a fair return on that investment.

Jan 1, 1951

By R. C. Gegg

The property of MacLeod-Cockshutt Gold Mines, Limited, is in the Little Long Lac area of the Thunder Bay Mining Division, Ontario, about four miles south of the Canadian National railway station of Geraldton. The town of Geraldton is about 170 miles east of Port Arthur and 22 miles west of Long Lac, which is on the main line of the Canadian National railway. The Trans-Canada highway passes through the property and during the winter season the road is maintained between Port Arthur and Long Lac. Electric power is supplied by the Hydro-Electric Commission of Ontario from their Cameron Falls plant and is distributed at 44,000 volts by a local transformer station. Early History The South orebody was discovered by diamond drilling in the spring of 1936. This is a porphyry contact orebody with major pyrite and minor arsenopyrite mineralization. Some gold is present in the 'free' state, but for the most part it is locked in the pyrite, with little or none in the arsenopyrite. Preliminary test work was based on comparing straight cyanidation with bulk flotation and cyanidation of the concentrates. The overall results by the two methods were found similar, but for economic reasons the flotation-cyanidation process was adopted. Before the mill came into operation, a new and entirely different type of orebody, consisting of massive sulphide lenses in banded iron formation, was discovered to the north of the existing workings. These bodies are an intricate mixture of pyrite and arsenopyrite, both carying gold.

Jan 1, 1949

By J. Bouchard, A. Desbiens, M. Maldonado, R. del Villar

ABSTRACT: Despite many years of practical applications in mineral processing plants, the potential of column flotation has still not been fully exploited. The challenge in measuring some key variables is certainly an important contributing factor to this situation. Reliable online measurement of varibles, such as the froth depth, bias, gas hold-up, frother concentration, bubble surface area flux, and bubble size distribution, provides opportunities for the application of various advanced control strategies and real-time optimization based on an economic criterion. For several years, Université Laval’sLaboratoire d’observation et d’optimisation des procédés researchers have been working on these opportunities. This paper describes the most recent advances and current research trends.

Jan 1, 2011

By L. Dorador

"In block caving projects, the rock mass fragmentation process plays a controlling role in the design and success of the operation. Poorly understood, however, is the secondary fragmentation that occurs as blocks of caved ore move through the draw column and interact with one another. The initial size of these blocks can be considerable, as can their strength and stiffness as the presence of non-persistent joints and veining will be variable. Intuitively, more planes of weakness within the blocks should facilitate early fragmentation, but this assumption could depend on additional factors such as contact type between adjacent blocks and loads imposed through varying heights of the draw column. This paper reports the findings from a laboratory investigation examining the role of block strength and planes of weakness on secondary fragmentation. Testing was carried out on small-scale concrete cubes of uniform size, with and without embedded planes of weakness. The results obtained demonstrate the significance of veining and other planes of weakness on secondary fragmentation under one-dimensional compression, and allow for the development and constraint of empirical guidelines.INTRODUCTIONThe fragmentation process during block caving involves the initial (primary) fragmentation of rock in the cave back through stress-induced fracturing, release and fall of individual blocks onto the broken ore muck pile. This is followed by secondary fragmentation involving splitting and rounding of blocks as they move downwards through the draw column towards the draw point. The degree of secondary fragmentation achieved involves many variables related to the mechanical properties of the rock blocks as well as different operational factors. With respect to the block properties, the presence of planes of weakness in the form of veining and non-persistent joints is a topic of special interest given the significant influence it potentially has on the overall fragmentation process. However, the inherent heterogeneity and variable size of individual blocks generated from the cave back makes it difficult to develop any empirical relationships relating secondary fragmentation to compressive loading based on insitu observations and mine data. More preferable would be to keep constant block parameters, such as shape (aspect ratio and angularity) and size, through controlled laboratory testing. This work presents an efficient technique to fabricate concrete cubes in order to keep constant different block properties. These are then tested under one-dimensional compressive loading. The objective of these tests is to emulate a tight packing condition of single blocks such as that which would occur when the air gap between the cave back and broken ore in the draw column is small. When the air gap is small, detached blocks are unable to fall and rotate but instead maintain a very tidy arrangement with minimal voids left between adjacent blocks."

Jan 1, 2015

By E. G. Leonardon

The question of geophysical prospecting is one that is beginning to occupy a pre-eminent place in the minds of those actively concerned in the discovery and exploitation of ore deposits. This is in marked contrast to the reception accorded such ideas when the Junior author, six and a half years ago, began introducing electrical prospectii1g to the mining fraternity on this continent. Happily, the mention of geophysics no longer evokes the sceptical and pitying smiles that it did in those days. A little reflection will show that modern geophysical methods are merely a logical development from pre-existing technique. In the study of geological problems, is it not logical to use all possible physical properties of matter? The study of crystal form and cleavage, the examination of thin sections of minerals by means of polarized light or ordinary light, in fact, utilize physical properties of minerals for the benefit of the geologist. These are, of course, laboratory methods, and the extension of the study of similar properties into field work was inevitable. This began with the magnetometric surveys, used as early as 1760 in New Jersey to locate iron ores. Eighty-four years later, John Locke's work in the United States resulted in pointing out relationships between the terrestrial magnetic field and main tectonic features of the earth's crust.

Jan 1, 1928

By G. F. Trainor

At the Canadian Natural Resources Limited (CNRL) Horizon Mine they use Wenco International Mining Systems Ltd (Wenco) Fleet Management System to monitor and control their production fleet with the goal of increasing operator productivity and safety, and raising dispatcher awareness and control. Amongst the broad productivity goals CNRL wanted to achieve with help from the system was a very specific need to blend ore at the truck level. CNRL uses 25m x 25m block geological model information to represent their complex ore body. Wenco's High Precision GPS application, BenchManager provides precise graphical actual-vs-design operator feedback and system integration. Together the two companies advanced the BenchManager product to meet CNRL's needs by using live camera feeds to compare activity with data collection that ultimately lead to changes in the algorithm to include enhanced GPS indicators and the support of a GLONASS assisted solution generating distance and bearing information.

May 1, 2011

By Andrew Matyas

"During the summer of 1968, the author was employed in the Research Department of Dominion Foundries and Steel, Limited, Hamilton, Ontario. Over the years, Dofasco has been conducting a program for developing more efficient control of its basic oxygen steelmaking process. The author was thus able to obtain a variety of viewpoints from both research engineers and furnace operators. He also had access to extensive literature dealing with BOF control schemes underway at other major steel producers. This paper describes the present state of developments in BOF steelmaking control.The necessity for efficient BOF control is pointed out. To appreciate the variables to be controlled, a brief outline of process fundamentals is included. Technical aspects of present methods of practical control are examined in detail; the relative merits of dynamic over static control models are emphasized. Finally, it is shown how an effective dymic-optimizing control scheme serves as the basis for closed-loop computer control of the process."

Jan 1, 1970

By M. Jackson, R. McDonald, T. Osken, D. Robinson

"The addition of sulphidic materials in the leaching of nickel laterites has several potential benefits that include improvements in the rheological behaviour of the blends, reductions in the sulphuric acid and steam requirements, sweetening of the nickel grade of the combined feed material, and the option of using a range of sulphidic materials. The current study examines the oxidative processing of 30% w/w blends of nickel concentrate and nickel laterite ore at 250oC. In particular, the viability of using low oxygen overpressures was examined for significant amounts of nickel flotation concentrate, up to 12% w/w. Further to this the impact of process water quality, in particular the presence of chloride, upon the kinetics of extraction and the mineralogy of the residue were also investigated. This paper will present the results of preliminary work in this area.INTRODUCTIONThe use of sulphidic ore as a source of sulphuric acid during oxidative hydrometallurgical processing is not a novel idea and can be traced back over forty years (Seidel & Fitzhugh, 1968). A series of patents pertaining to application of this approach for laterite ores can be subsequently found (O’Neill, 1973; Opratko et al., 1974; Rodriguez, 2008a, 2008b; O’Callaghan, 2010; Liu et al., 2011) and a few of articles containing published data (Ferron & Fleming, 2004; Quinn et al., 2009). The use of pyrrhotite tailings as a source of sulphuric acid has also been employed for the leaching of converter slags (Perederiy et al., 2011).It is known that hydrometallurgical operations such as the HPAL plant at Murrin Murrin have added small amounts of sulphides as either transitional (mixed sulphide/oxide) ore or non-smeltable concentrate. This can improve the rheology (Rodriguez, 2009) and provide heat credits. However these plants are generally limited in their ability to add such materials due to their reducing nature and given under highly acidic conditions that the breakdown potential of the titanium used for the autoclave lining is significantly reduced. A suitable oxidant must therefore be present to ensure the potential remains sufficiently high."

Jan 1, 2012

By P. Moreno

ABSTRACT: The Maras salt terraces, located between Cuzco and Urubamba in the Andes (southern Peru), are living examples of traditional Incan salt production, where present-day artisanal miners produce salt from shallow pans by solar evaporation. In these terraces, natural spring water, eight to nine times saltier than seawater, is used to produce the salt. The field observations and chemical analyses show that the poorly crystalline traditional salt is finer in particle size and contains impurities such as dolomite and gypsum. These differences are the result of shallow pond depth, contamination from wall erosion, and the nonsequential mode of salt crystallization.

Jan 1, 2011

By The Staff

Introduction In this paper it is proposed to discuss briefly some of the problems confronting the management of a gold mine in choosing a method of milling to recover the gold from various classes of ore. In order to simplify the discussion, the more common types of gold ores are classified from a metallurgical point of view as follows: Class 1?A: Free-milling ores which require only relatively coarse crushing. B: Free-milling ores which require finer grinding to release the gold. Class 2?A: Gold ores which contain the gold partly in the flee state and partly associated with a small amount of iron sulphide, and which do not require fine grinding. B: Gold ores similar to 2A, but which require fine grinding. Class 3?A: Gold ores containing copper in quantities insufficient to interfere to a serious extent with cyanidation. Gold ores containing copper in sufficient quantity to interfere with cyanidation but in which a large proportion of the gold is in the free state, the remainder being chiefly associated with the copper mineral, chalcopyrite. Gold ores containing copper and other sulphides, such as pyrite, etc., in which the gold is principally associated with these sulphides.

Jan 1, 1931

By H. C. Cooke

Those who have followed the geological developments in connection with the copper deposits of Quebec will recall that on many properties the sulphide bodies occur as replacements of fault breccias or tuff breccias, and exhibit a pronounced distaste for the more massive lavas. At the same time the rocks around the ore-bodies are profundly altered, first by addition of silica and sericite, later by conversion of these minerals into chlorite. It has been known for some years that at the Amulet and Waite-Ackerman Montgomery mines these conditions do not prevail. At both mines the ore-bodies are replacements of massive lavas, and at the Amulet they are associated with a very peculiar rock christened ?spotted dog', or 'dalmatianite'. Accordingly, when in 1929 the writer had the opportunity to make a further examination of these properties, two problems presented themselves for solution. The first was to determine, if possible, the conditions under which massive lava, rather than breccia, is replaced by the sulphide masses; the second, to find out the exact nature of dalmatianite and its relations to the sulphide bodies. The first of these problems is believed to have been solved; the second has been found very complex, and will require further work before it is satisfactorily settled.

Jan 1, 1930

By M. Jarvis, D. B. Dreisinger, T. Hitchins

Mineral carbonation (MC) has been extensively researched all over the world since it was found as a natural exothermic process to permanently and safely sequester CO2. In order to accelerate the natural process, various methods for carbonation of Mg-/Ca-silicate minerals and other industrial wastes have been studied. It has been found that the MC efficiency will increase with an increase of CO2 pressure, retention time, temperature, mass ratio of Mg or Ca to Si in minerals, specific surface area, and the slurry concentration in a specific range, and with the introduction of an effective catalysts, for example, 1M NaCl and 0.64M NaHCO3 or carbonic anhydrase. However, there still is not a successful industrial application because of high economic cost and slow reaction rate. It is not economic to exploit Mg- and Ca-silicate minerals deposits or tailings to sequester CO2 by MC, due to the cost of grinding and heat pre-treatment and in some cases the whole sequestration process may result in more CO2 emissions than the amount of CO2 sequestered, due to the requirements of energy inputs. The process however, may be profitable as a whole (with carbon credits). It is suggested to combine MC with recovery of valuable metals from ore deposits in order to reduce the cost for MC by cost sharing for mineral recovery.

Jan 1, 2017

By M. Rizwan

Mine workings are progressing to greater depths as shallow mineral resources are being depleted, and civil engineering projects are nowadays being developed at substantial depths. The threat to tunnel stability posed by rockburst events has increased as a result of these high stress environments. Rockbursts are violent events capable of mobilizing large volumes of rock. In addition to the threat to safety and equipment, rockburst damage can significantly impact on operations, and cause loss of mining production, often the largest cost component of such events. Rehabilitation of such damage requires significant effort and resources. Tunnel walls and roof are usually well supported, but the installation of rock support in the floor is uncommon, particularly in mining environments. In the absence of rock support, floors of the excavations are vulnerable to rockburst damage. New concepts for containing damage of excavation floors by dissipation of the large transient forces using simple techniques or preselected and designed elements of sacrificial floor systems are presented. Two approaches to calculate the demand are presented: estimating load demand by assuming displacement levels and a response modification factor; and using a limit displacement approach to calculate elastic stiffness of the selected elements of the sacrificial support system. The proposed conceptual support systems have the capability of dissipating rockburst energy while retaining sufficient serviceability. It is considered that the concepts presented, for discussion, in this paper are logical and developable into practicable and economic solutions for tunnel floor support in rockbursting environments.

Jan 1, 2015