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By J. H. Douglas, A. F. Matheson

"The Hard Rock is the most easterly producing mine in the Little Long Lac area. The Company was formed in 1934 to develop a surface showing of gold in quartz made by a prospector, W. W. Smith, in 1931. Although some ore was eventually produced from this discovery, the principal orebody, hidden below 10 feet of muskeg, was found about 1,000 feet to the north by exploratory diamond drilling early in 1938 from the No. 2 shaft workings at the 250-foot level.Production started in 1938 and to January 1, 1947, 201,000 oz. gold had been obtained from 1,165,282 tons of ore mined and 869,397 tons milled. Of this ore about 15 per cent came from the development and mining of the original orebodies discovered at the surface. The remainder came from the ore found by the underground diamond drilling done in 1938. Of the latter ore, the Company estimated, at January 1st, 1947, only 140,000 tons remained. The orebody, therefore, contained approximately 1,100,000 tons.OREBODIES AND GENERAL GEOLOGYThe orebodies of the Hard Rock mine are of two main types: the quartz ore of the south and No. 1 shaft zones, and the sulphide ore of the north zone. The quartz ore consists of white quartz veins mineralized with sparse, fine, light-coloured pyrite, or, less commonly, nests of coarse, crystalline, light pyrite. A little tourmaline, scheelite, pyrrhotite, chalcopyrite, arsenopyrite, and native gold are also present. Native gold occurs in a few places in quartz veins in exceedingly rich cemcentrations, apparently where there are large, light-coloured, pyrite crystals of imperfect form. The ore of the north zone is massive pyrite with arsenopyrite and in places pyrrhotite. Many short irregular quartz veins, from a few inches to 2 feet in width, are also present, but the quartz forms a very small percentage of the whole. The veins may be flat to vertical, and sulphides on one or both sides replace the host rocks. The gold is closely associated with the sulphides . The quartz is commonly barren except where it contains sulphides or along the borders of the sulphide ore zone where native gold is not uncommon in quartz stringers."

Jan 1, 1954

By Louise Laverdure

The Canadian mining sector has to be innovative and invest in the development of sustainable mining technologies to maintain its international leadership. Natural Resources Canada (NRCan) collaborated with the Canada Mining Innovation Council (CMIC) to define the Green Mining Initiative (GMI) and in order to focus its R&D activities on industry and other stakeholders? needs. The GMI was launched in 2009 to spur innovation in the mining sector and further enhance its environmental performance. The initiative, led by CANMET- Mining and Mineral Sciences Laboratories (MMSL), takes a holistic approach looking at the entire mining life cycle, from design to closure and beyond, through four innovation and research pillars: ? Footprint Reduction, ? Innovation in Waste Management, ? Mine Closure and Rehabilitation, and ? Ecosystem Risk Management. The Canada Mining Innovation Council has also been creating a new initiative on Sustainable Mining, which will bring further focus to environmental aspects of mining, and engaging wide range of research providers to develop research programs complementary to GMI goals.

May 1, 2011

By R. M. de Carvalho

Empirical and phenomenological models of SAG and AG mills have dominated the scene for the last few decades, being used nearly every time a mill is scale-up or an attempt is made to improve its performance. However, in spite of their success, these models fail to describe the details of both the grinding environment and the breakage mechanisms. The result is a generally good track record, with a few – but very important – instances when these models fall short in their predictions, which can be very costly. Further, nearly all of these models require detailed calibration to industrial and pilot plant data, being costly in their application, although still with limited predictive capabilities. Recognizing these challenges, a new model framework has been proposed which overcomes the limitations of currently used models by coupling the microscale population balance model, the discrete element model and functions that describe internal classification at the mill grate. This model framework has already been applied to describe breakage in ball mills, with showing very promising results. However, in the case of SAG and AG mills a much greater level of complexity is involved in the model, given the interaction between the mechanical environment that is formed totally or, in part, by the ore itself, and the breakage response in the mill. The paper describes the model framework, demonstrating how it can address appropriately effects such as mill speed, mill filling and size distribution, on the response from the mill. Some of the advantages of the model are related to its intrinsic multi-component and dynamic nature, which allows simulating appropriately mixtures of ores of different competences in a transient manner.

Jan 1, 2012

By P. M. Hedley

GOLD mining in Nova Scotia, as in any other gold district, has its own peculiar problems. Being in close proximity to excellent roads and to railways, and being blessed with good labour, the majority of gold mines in the Province find their paramount trouble is geological, namely, ore finding. After six years of continuous mining at Goldenville, the staff of Guysborough Mines, Limited, has collected many facts, has come to some definite conclusions, and has made a lot of guesses, some good and some bad. It is the purpose of this paper to set down such information as we have been able to gain in the hope that it may prove useful to other operators, present and future, faced with similar problems. What may be true of one Nova Scotian mine will not necessarily be true of another, so that the observations that follow should be considered as primarily applicable to Goldenville. Stated facts, conclusions, and theories are the result of the combined thought and effort of Head Office officials, of members of the Provincial and Federal Departments of Mines, and of members of the mine staff, past and present. Grateful acknowledgment is made to all.

Jan 1, 1941

By J. W. Reynolds

This paper describes the function of the research and development department of a large mining organization and the benefits which can be derived over the years. Examples are given of work done in rock drilling, ventilation, noise control and the development of backfill stowing machinery.

Jan 1, 1970

By Jakob Janzen

This paper demonstrates that the introduction of a Battery Energy Storage System (BESS) into an isolated diesel generator based grid has the potential to reduce the electricity cost and deliver a good return on investment. Energy storage also allows for increased renewable energy penetration, into the isolated grid, that further reduces the electricity cost. The isolated power system studied includes several diesel generators of different sizes. The typical operating pattern is for the generators to be run at 80% to 85% of their power rating to deal with load fluctuations. Operating the diesel generators near their full power rating, however, improves their efficiency, in this case, while the frequency and load control can be carried out by the BESS. Operating the diesel generators near their full power rating reduces the number of generators which need to be operating to support a given load. As a result, the improved efficiency of the diesel generators and reduced maintenance cost, for operating fewer machines, are the reason for the savings.

Aug 1, 2013

By S. Yadav, T. G. Murthy, C. Saldana

"An experimental study has been carried out in order to study the deformation of porous brittle materials under plane strain indentation. Gypsum, which is well known model system for understanding the behaviour of soft rocks, is used in this study. The effect of wedge angle is investigated in this research through this series of experiments, using wedges of 3 different apical angles. High-speed, high-resolution images are captured using a CMOS camera during the experiment. The images obtained are analyzed using a Particle Image Velocimetry (PIV) algorithm in order to obtain the evolving velocity, strain-rate and strain fields.INTRODUCTIONThe problem of indentation, which is usually referred to in the context of hardness testing is ubiquitous as a material characterization technique for a large class of solids. Mechanical properties of materials such as yield stress, flow stress, fracture toughness, elastic moduli etc. can be related to the hardness of a given solid. The indentation problem involves a given material or solid (whose properties are to be determined) indented by a relatively harder material (indenter) allowing the solid to undergo plastic deformation, which is then related to the yield stress of the material. The problem of indentation and its variants see many applications ranging from mining and petroleum industry, infrastructure industry, manufacturing, and biomedical sectors. Indentation has been extensively studied in metals, with accurate measurement of deformation parameters, stresses and comparison with analytical solutions. On the other hand, understanding of indentation in other class of solids such as cellular solids, porous solids, rocks, and soft solids is still nascent. In case of rocks, a comprehensive understanding of the indentation problem is very crucial because of the obvious applications in mining, petroleum and infrastructure sectors. The inherent porosity, the brittle nature of the rocks, adds to the complexity of indentation in these porous brittle solids. Various theoretical models with degrees of simplifying assumptions have been proposed to study the indentation in rocks. The most common model used in the study of indentation in rocks is a cavity expansion model, wherein a blunt indenter indenting into a rock is approximated with the expansion of cylindrical or spherical cavity in an elastic-plastic material. Complementary studies in understanding fracture initiation and propagation due to indentation has been largely based on the studies of traditional brittle materials such as glass."

Jan 1, 2015

By Tim Gitzel

Thank you for your introduction, and thank you to the CIM for inviting me to make a presentation to you today. This is my first opportunity to report to you on the status of the Canadian uranium industry and I am pleased to tell you that the industry is in good shape, and well positioned for the future. As you will no doubt be aware, Saskatchewan benefits from the world?s largest known highgrade deposits of uranium as well as from a high level of provincial, public and northern community support. It is within this unique combination of geology and community that our industry operates. Uranium markets have been extremely competitive for a number of years for several reasons. First, deregulation in the nuclear electric power industry has tended to encourage fuel buyers to use up their large inventories built up at a time when rapidly increasing demand was anticipated. Second, alternate sources from surplus commercial stocks, military materials and reprocessed fuel have presented a major additional source of uranium supply. Today, these secondary supplies are meeting about half of uranium reactor feed requirements. Canada (that is, Saskatchewan) is the world?s largest ?natural? uranium producer with about a third of the global production. Saskatchewan?s mines produced more than 30 million pounds of yellowcake in 2002. Despite low prices, steady demand for uranium will continue. In fact, an increase in world uranium production in 2002 helped feed a more than 3 per cent increase in reactor fuel demand. Low cost production is important for surviving low market prices, but investments are based on longer-term strategies rather than simply responding to market cycles. Cost is not the only issue. In these times of increasing regulatory and public scrutiny we must continue to earn the trust of our stakeholders by adopting the highest standards and staying on the leading edge of technical, social and environmental developments. Managing these issues is as important as traditional concerns of ore grade and cost of production. The last two decades of the 20th century saw the Province of Saskatchewan rise to prominence as the leader in uranium production from facilities, which were at the time deemed world class. These facilities are now either at - or nearing - the end of their production years. We are now bringing on new facilities that will position Saskatchewan to remain the world leader in uranium production for many years to come.

May 1, 2003

By R. M. Berry

A brief outline of refining methods used to (1) upgrade yellowcake to nuclear purity and (2) convert the uranium to the chemical and physical forms required by the fuel fabricators is presented. The uranium hexafluoride (UF6) production facility now under construction at Eldorado, Port Hope, is discussed. Technological improvements in uranium refining are considered.

Jan 1, 1969

By M. S. Ünal

Creation of 3D model of coal seams is a tedious and time consuming operation. Computer aided 3D solid modelling of coal seams can be performed in a fast and detailed manner. However, in case of having tectonically disturbed coal seams where faults may be observed, expert opinion is necessary to decide the geometry of the coal seam. The aim of this study is detection of fault zones with computers by using drill hole data. Firstly, a digital database is generated by using the drill hole data. Surface models of the layers are produced by applying triangulation method on coal seam roof elevations. The generated surface is divided into small squares and consequently dip and dip direction values are calculated for each square. Variograms for dip and dip direction are determined and maps showing the variation of dip and dip direction are generated by using geostatistical methods such as kriging and co-kriging. Examination of disconformities observed on estimation maps created by kriging and co-kriging clearly reveals the extension of faults. The method used in this study is applied to detect fault lines of a known mine field. 3D solid modelling of the coal seam has also been performed by using conventional cross-section method. The results of both methods were in good agreement. Identification of major faults by using the method introduced in this study could certainly simplify 3D solid modelling of coal seams.

Aug 1, 2013

Kahama Mining Corporation Limited (KMCL), a wholly owned subsidiary of Barrick Gold Corporation, operates the Bulyanhulu gold mine. The operation has been in commercial production since April 2001 and is the first modern underground mine to be developed on the Lake Victoria goldfield in Tanzania. Bulyanhulu is located in a major mineralised system along an emerging gold trend. This area, the Lake Victoria Greenstone belt, has been the focus of significant exploration and development programs since 1994, with over 34 million ounces of gold having been discovered and four new mines commissioned. The Bulyanhulu project has accounted for just over a third of the gold resources discovered during this period. From an initial exploration program, which outlined a resource of 1.37 million ounces of gold, Bulyanhulu now hosts a reserve of some 12 million ounces in a resource base, the limits of which are, as yet, undefined. The Bulyanhulu property is located approximately 56 km south of Lake Victoria, in northwestern Tanzania, eastern Africa. A Mining Licence issued by the Government of Tanzania on July 23, 1999 grants to KMCL the exclusive right to mine a concession area covering 51.48 km2. The property is reached via a 75-km road from the main road to Dar es Salaam. The nearest towns are Mwanza to the north on Lake Victoria, 155 km by road and ferry, Kahama, 86 km by road to the south and Isaka, 126 km by road. Isaka is on the rail line between Mwanza and Dar es Salaam and has facilities to receive heavy equipment, and a fuel depot. A gravel airstrip, 1,700 m long has been constructed at the property.

May 1, 2003

By Wei Wei

Mining induced ground movement and/or stress redistribution could cause ground instability issues. This is particularly true when the extraction of large stopes is done with one or two large production blasts. Often enough, it is the nearby mine development like haulage drifts and cross cuts that are influenced the most by production blasts. Proper and timely mitigation of ground control issues due to stress redistribution is required. This is usually done by drift rehabilitation involving the installation of secondary support system in the affected areas of the mine development which include; slashing, wire mesh, and in some cases the use of shotcrete liners. It is imperative that such rehabilitation be implemented to the mine infrastructure in a timely manner in order to avoid aggravated ground control problems and production delays. If the real time performance of the support system is captured, it would be possible to determine the timing for rehabilitation job. Birchtree Mine in Thompson, at the Vale Manitoba Operation, has begun mining the 84 Deep Orebody. One of the identified risks is the stability of the crusher room under mining induced stress redistribution. It is proposed to use the U-Cell technology to monitor the primary support system performance (rebar bolts and extension bolts) and monitor the real time performances of the bolt axial loads. The U-Cell technology is a 7-inch long, coupler load cell that is screwed onto the threaded portion of a rock bolt prior to installation. Rehabilitation in the vicinity of the crusher area where U-Cells are installed is recommended when the bolts have reached 70% of their yielding capacity. Catastrophic ground failure can be avoided by adding secondary support in a timely fashion. This paper presents a case study at Birchtree Mine in Thompson Manitoba, where the performance of primary ground support system is monitored and recorded during production.

Jun 1, 2012

By Chuck Crowell

ISO Standards ?Provide Information to Address Commercial and Safety Needs for Standardization: ?Definitions and Terminology ?Test Methods ?Performance Criteria ?Conformity Assessment Process ?Developed by Global Experts ?Promote Global Harmonization

May 1, 2013

By B. R. Rakishev

Balanced development of mining works at all the benches of a working zone by use of the excavator-automobile complex is achieved by transition to the technology of the bench excavating with cross panels by the two-sub-bench scheme with the changing levels of the working platforms (is patented in Kazakhstan). In deep quarries realization of this technology will allow to reduce the current volumes of the stripping ore excavation by 10?15 % and more, to increase the opened reserves of minerals by 20?50 % to decrease volume of mining-capital works for construction of stripping excavations by 2?4 times and to provide efficient use of powerful excavator-automobile complexes.

Aug 1, 2013

By J. P. Messervey

As a result of my field examinations in this Province, I have been struck by the evidence of widespread mineralization in rocks, particularly the limestones of Carboniferous age. Six prospects of lead and zinc or lead alone scattered through the eastern part of the mainland, one copper prospect and three veins of siderite, all point to a period of mineralization subsequent to the forming of the Carboniferous rocks in which they occur. While none of the present prospects are of proved economic importance, still it is possible, and indeed probable, that further prospecting will find concentrations sufficiently large to make mines. It may possibly aid the prospecting for these base metals if the present scraps of information are assembled from various sources, and I will further briefly recount the information as a result of my observations. Gay?s River At Gay's river, midway between Halifax and Truro, and four miles east of the railway, numerous pits and natural exposures show galena and sphalerite in limestone of Carboniferous age, near where it lies unconformably upon slate and quartzite of the gold series. These exposures extend for a length of over one thousand feet along a curving contact. The pits show that on the contact there is a fossiliferous and somewhat porous layer of limestone, which is so impregnated with galena and small amounts of sphalerite as to be of ore grade. Wherever observed, the thickness of this layer is less than two feet.

Jan 1, 1929

By D. A. Brown, C. Lowe

"Abstract -A multi-sensor (electromagnetics, magnetics, gamma-ray spectrometry, and VLF) geophysical survey was recently conducted in the Purcell Basin of southeastern British Columbia in an area encompassing the world-class Sullivan Sedex deposit. The purpose of the survey was to geophysically characterize the known mineral occurrences and to develop strategies to enhance future mineral exploration in the basin. Follow-up investigations of geology and measurements of rock physical properties helped constrain interpretations of the geophysical data sets.Despite extraction of more than 90% of the ore from the Sullivan deposit, it is clear that the mineralization there, as well as at other Sedex occurrences surveyed, is characterized by high conductivity values, strong bedrock conductors, and elevated magnetic anomaly values. The albite-sericite alteration which accompanies this mineralization yields high potassium and low thorium-potassium ratio values. Associated Moyie gabbro is characterized by low electrical conductivity and radioelement concentrations and by high magnetic anomaly values. The study has also aided exploration for other mineral deposit types including stratabound Cu-Ag, placer gold, vein and disseminated basemetal deposits. In addition, the geophysical data have helped constrain geological interpretations of the basin."

Jan 1, 1998

By P. I. Laforest, M. S. Moats

"Antimony in smelted copper anodes has been shown to cause problems in electrorefining including brittleness of starter sheets. In order to improve deposit properties, a study was conducted examining the effect of anode chemistry on cathode ductility and electrolyte chemistry. Two industrial anodes with different molar ratios of As/(Sb+Bi) were used in laboratory electrorefining experiments with commercial electrolyte, and the addition of commercial glue and Avitone. The ductility of 21-hr copper deposits was evaluated by a 180° bend test. X-ray diffraction (XRD) and metallography were performed on unbent specimens to characterize the deposit structure. Increasing the anode As/(Sb+Bi) molar ratio from 0.54 to 3.8 resulted in an increase, on average, from four to eight bends to failure in cathode material produced. Significantly lower concentration of antimony (V) in the electrolyte was detected when operating with the higher molar ratio anode. The presence of (111) and (200) planes was noted in cathode material produced from the higher molar ratio anode suggesting that mixed growth character could be responsible for the observed increase in bend test results. The ductility of the starter sheet materials was improved by a higher anode molar ratio.INTRODUCTIONThe presence of antimony in copper electrorefining electrolyte has been reported to cause problems in cathode production (Hiskey, 2012; Peng, Zheng & Chen, 2012; Wang, Chen, Zhou-Lan & Lian-Sheng, 2006; Wang, Chen, Zhou-Lan, Wang, Xiao & Zhang, 2010; Wang, Chen, Zhou-Lan, Wang, Xiao & Tang, 2011; Wesstrom, 2014). To better understand the impact of antimony, laboratory scale electrorefining experiments were conducted using industrial inputs (anodes, cathodes and electrolyte). The influences of anode chemistry on the valences of antimony and arsenic in the electrolyte were monitored and correlated to physical cathode characteristics, such as a bend test to failure and crystallographic orientation.Commercially, starter sheets are produced by electrorefining impure cast copper anodes onto titanium blanks. The starter sheets are then hung in an electrorefining or electrowinning cell using loops of bent starter sheet material. These loops, in the absence of sufficient ductility, fail resulting in cathodes falling into the electrolysis cells. It is thought that the reduction in ductility can be related to anode composition; in particular, the molar ratio of arsenic to antimony plus bismuth As/(Sb+Bi). It has been stated that maintaining this ratio above 2:1 results in numerous improvements to electrorefining operations (Baltazar, Claessens & Thiriar, 1987; Kamath, Mitra, Radhakrishnan & Shetty, 2003; Krusmark, Young & Faro, 1995; Noguchi, Itoh & Nakamura, 1995; Wenzl, 2008)."

Jan 1, 2016

By D. B. Nazzer

"ANY DISCUSSION of energy today is incomplete without consideration of nuclear energy. In the Maritimes, with plentiful supplies of coal, with relatively easy availabilty of imported oil brought in to the deepwater terminals, with future sources of large supplies of oil and gas anticipated from under our neighbouring continental shelf, and with the Fundy tides, you may question why nuclear energy should be considered. What follows may not give you a specific answer to that question, but it may provide a basis for better understanding. Energy from the sun, from hydraulic sources and from combustion has been available to man from prehistoric times, for thousands of years, but the most sophisticated source of energy, the actual conversion of matter into energy by man, has been developed entirely within the last one-third century, since the discovery of fission in 1939, and the application to generation of electric power has all been done within a generation or less. The pressure of military needs during and after the second world war was largely responsible for the speed of initial development, by funding and focussing the effort needed to develop the basic technology, and in particular materials. The U.S. defence program yielded, for example, the large-scale isotope separation processes for fissile U'35 and for heavy water. The nuclear submarine program yielded zircaloy, a key structural material for the core of the Canadian Candu type reactor."

Jan 1, 1972

Centralia?Mine Operations ?Centralia Mine ?Mountainous Terrain ?High rainfall (greater than 50 inches/yr) ?Multiple Pit/Multiple Seam ?Truck/Shovel Prestripping ?Dragline Overburden ?Coal Wash Plants

May 1, 2001

By G. C. Laurence

"This paper discusses the hazards and extensive precautions taken in Canadian uranium mines, concentrating plants and processing plants. It also outlines Canadian policy regarding the control of the sale and distribution of uranium and other nuclear materials.OVER THIRTY YEARS AGO, I spoke to The Canadian Institute of Mining and Metallurgy here in Montreal about radioactivity and its dangers. I must have made quite an impression thirty odd years ago, because now you have asked me to do it again. Of course, the picture has changed. Then they were mining uranium ore, recovering the radium from it and throwing away the uranium. Now they are still mining uranium ore, but are throwing the radium out on the tailings dumps. Thirty years ago, most people did not know what ""radioactivity"" meant. Nowadays, they have beard that it is dangerous, and some of them, recently, be-came worried about the radium in the tailings dumps and what becomes of it."

Jan 1, 1969