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By B. R. MacKay

Introduction The Corbin coalfield is one of the smallest, and at the same time one of the principal, producing bituminous-coal areas in southeastern British Columbia, and is unique on account of the great original thickness of one of its coal seams and the remarkable concentration of coal in a small area that has occurred through intense folding and faulting of the measures. These are such that the deposit has been referred to at times as "the world's thickest coal seam" and as" a mountain of coal." The determination of the number, thickness, and character of the seams present, and the structure, extent, and geological relationship of the several deposits, are of vital interest both to the operating company in its endeavour to evolve the most efficient method of mining these exceptionally thick deposits and to the Government in estimating the coal resources of the different fields. With the object of ascertaining these data the writer was assigned in 1930 to geologically map and study the Corbin coal deposit. A topographic map covering Coal mountain and the immediate vicinity on a scale of 1 inch =800 feet, with a contour interval of 25 feet, made by the Topographic Division of the Geological Survey, served as the base for the geological mapping.

Jan 1, 1931

By Y. Guglielmi, C. Gout, P. Henry, P. Dick, C. Nussbaum

For a decade, observations and experiments conducted in underground environments worldwide (mines, underground research laboratories - URL) made it possible to bridge the scale gap between laboratory scale and large scale faults. Indeed, underground rock laboratories allow developing decameter scale relatively well constrained experiments at the smallest distance from the hypocenters. URL’s experiments allowed developing new monitoring technologies coupling pressure-strain-seismic measurements and reproducing complete earthquakes sequences analogous to natural ones. They also allowed exploring past movements of faults and sometimes also paleofluids in three dimensions and characterizing different fault architectures and hydromechanical properties in unaltered conditions. This is particularly important in the study of faults affecting clay formations which could not be observed at the Earth’s surface because of the high alteration. Here we show how examples from the Mont Terri (Switzerland) and Tournemire (France) The URLs may help in (i) defining the concepts of fault architecture in shales, (ii) estimating fault hydromechanical properties from field decameter scale experiments. Some key results are that faults which are critically stressed or at the rupture limit can reactivate for stresses variations within the range of those produced by shallow underground excavations, and that slight micrometer-to-millimeter scale reactivations may lead to large factor-of-10-to-1000 permeability increases. Such promising results show that URL’s experiments may bring new insights on some key processes that control the relations between fault stability and permeability evolutions in very permeable layers.

Jan 1, 2015

By R. Amata

"The Gakara Rare Earth deposit in Burundi (East Africa) is unique for its high grade (e.g., 54.3% TREO on average) and low uranium and thorium levels. The majority of the light rare earth (RE) elements in material from Gakara are contained within the familiar RE minerals bastnaesite and monazite. Extensive metallurgical test work was conducted by SGS Minerals Services on mineral samples collected from the Gakara deposit. Various whole ore hydrometallurgical processing routes were examined in a scoping level test program. Preliminary beneficiation testing was also conducted, though it was determined that only marginal upgrading would be achieved with significant RE losses. Thus a hydrometallurgical process on whole ore was developed to minimize the overall process complexity and achieve maximum RE recovery. Results from the test work will be presented, along with the selected base case flowsheet involving agitated atmospheric sulphation of the RE minerals, RE double sulphate precipitation, caustic conversion, redissolution, and carbonate precipitation. Following the base case flowsheet, a purified cerium free mixed RE carbonate with low levels of radioactive elements was produced.INTRODUCTIONRainbow Rare Earths Limited (Rainbow) is a mining company engaged in the exploration and development of the Gakara rare earth deposit in Burundi; Figure 1 shows the project location. The project is located in the Bujumbura Province and 45 km from the Burundi capital of Bujumbura. Notable for its exceedingly high in-situ grade – 54.3% on average total rare earth oxide (TREO), low uranium and thorium levels and familiar rare earth minerals, bastnaesite and monazite – Gakara is the world’s richest rare earth deposit. The project, a previously operating mine from 1948–1978, has a significant mineral inventory base, a long life of mine, well understood mineralogy, and robust economics. Rainbow is focused on bringing Gakara into production in the near term, ramping up to produce 5,000 t/y of a 54%+ TREO concentrate."

Jan 1, 2016

By S. L. Gertsman

Canadian steel foundry practice has made marked progress during the past decade. Equipment suppliers, development engineers, and foundry personnel have focussed their attention on every phase of the foundry operation, with a resulting lower demand on manpower and materials. Also, more rigid specification requirements as to dimensional tolerances and quality have necessitated improvement and increased control at every stage from the pattern shop to the cleaning room. The growing trend toward mechanization is clearly evident. Equipment such as sand mixers, sand reclamation systems, material handling devices, moulding machines, core blowers, etc., is being increasingly employed by the steel foundryman. This equipment not only increases production but also tends to lessen the human variable so prevalent and disconcerting in the early days of steel founding. The result has been an improved and more reliable steel casting, which is gradually obtaining wider acceptance by design engineers. The purpose of this paper is to discuss briefly some of the practices being used, and also the direction of development that is being pursued by Canadian steel foundrymen.

Jan 1, 1948

By D. McConchie

BauxsolTM, prepared by treating bauxite refinery residues with Mg2+ and Ca2+, has an excellent ability to remove arsenic from acidic waters. The addition of BauxsolTM to sulphidic waste rock at the Gilt Edge Mine, South Dakota, reduced As concentrations in leachate water from 35 mg/L to < 0.005 mg/L; the concentrations have remained below 0.005 mg/L for the five years since the treatment was initiated. However, ordinary BauxsolTM does not effectively remove As from near-neutral water and it needs to be acid-treated or blended with small amounts of reagents, such as jarosite or ferrous sulphate, to increase the proportion of positively charged binding sites on the particles. The use of a jarosite/BauxsolTM blend can effectively treat ponded water, and As(V) concentrations can easily be reduced from over 1 mg/L to < 0.001 mg/L; As(III) has to be oxidised to As(V) for effective removal. Metal contaminants in the jarosite are trapped by the BauxsolTM and only very small amounts of the As, or other elements bound during treatment, are liberated using a TCLP leaching test. The exhausted treatment reagents meet the criteria for classification as an inert solid and do not need to be disposed of in a secure repository.

Jan 1, 2006

By J. M. Réjean Gagnon

"Quebec Cartier Mining Company is currently mining a low-grade iron ore deposit in northeastern Quebec. The Company is producing some 8,000,000 dry gross tons of concentrates per year, grading about 66 per cent iron. The pit, which is located on the keel or hinge line of a fold, will eventually be about 1,000 feet deep with a surface area of 8,000 by 2,600 feet. The most significant structural discontinuities in the mine are the natural bedding planes and secondary perpendicular joints. The exposed walls are subjected to a sub-Arctic climate and heavy blasting occurs approximately six times a month.QCM utilizes design and operating techniques to control rock fall. Steps are also being taken to analyze the ultimate over-all pit slope stability."

Jan 1, 1968

By D. R. Pyke, R. S. Middleton

"Three main types of base metal sulphide mineralization are present in the Timmins area:(1) -Massive and stringer-type copper-zinc deposits occurring mainly in pyroclastic rocks, as typified by the mines of Kam-Kotia, Jameland and Canadian Jamieson, or within or close to possible breccia pipes as shown by the Genex and Kidd Creek mines. With the exception of the Kidd Creek mine, all of these orebodies occur northwest of Timmins (Kamiskotia area) and appear to lie within or close to a major center of volcanic activity characterized by a thick accumulation of felsic pyroclastic rocks and subordinate epizonal intrusions. The margins of the rhyolitic pile are interfingered with mafic volcanics; overlying sedi-ments mark the termination of a vol-canic cycle. The copper-zinc deposits in the Kamiskotia area are confined to a particular stratigraphic unit. Ore-bearing solutions were probably derived from the intrusive complex of the volcanic pile.(2) -Porphyry copper deposit of the Mcintyre mine. The deposit occurs in a quarz porphyry intrusion related to the volcanism in the area (Hurst, 1936). Mineralization was probably introduced at the time of intrusion, and subsequently redistributed within the porphyry during deformation. (3) -Massive and disseminated nickel mineralization, associated with serpentinized alpine-type ultramafic intrusions, as shown by the Alexo, McWatters, Hart, Inco and Texmont deposits. The nickel mineralization occurs at or near contacts of the serpentinites with felsic or mafic volcanics, or sulphide-bearing iron formations. The nickel deposits south of Timmins are confined to a particular stratigraphic unit along the margins of domical-shaped structures which appear to outline former volcanic centers. Sulphurization as pro-posed by Naldrett (1966) appears to be a workable hypothesis for the formation of some of the deposits."

Jan 1, 1971

By C. G. Williams

IN preparing this paper on Canadian mine taxation, there has been no attempt to detail the requirements of the various taxing bodies; but rather to consider the matter from the standpoint of its underlying principles and give a general idea of the methods adopted. I have added an Appendix setting forth the principal features of the various Acts, which should be used for general reference only, since new rulings alter minor details from time to time. In current legislation, many important points are left to the discretion of the Ministers and their deputies. We are, indeed, fortunate in having in Canada an able and conscientious body of permanent officials, who bring a sense of justice and courtesy to their work which is most commendable, and which has done much to simplify the working out of general problems. The production of metals may rightly be deemed a form of manufacture, but differs from the average manufacturing business in three important respects: (1) In its early stages, it is wholly speculative, since it is impossible to make any definite appraisal of value or possibilities. (2) The principal asset of any mine, i.e., the ore in the ground, is a wasting asset, and is irreplaceable. (3) Any additional burden by way of taxation cannot be passed on to the public but must be borne entirely by the producer. Having regard to the first of these differences, it is apparent that, since the risk of loss is great, the reward in case of success must be correspondingly great. This fact seems to be constantly overlooked by those who regard the all too few outstanding successes in Canadian mining history as fit prey for predatory legislation. As an illustration of the speculative nature of early mining development, let us consider the Province of Ontario-and I take this illustration simply because I am more familiar with conditions there, and not because I believe it differs greatly from any other province. From 1907 to 1933, 165,243 claims were staked and recorded, from which 43 mines were developed which paid one or more dividends. There was, of course, some duplication through re-staking; also, on some claims very little work was done, and most mines have more than one claim. But, since staking and recording cost real money and effort, each of these claims must have been considered to have had merit.

Jan 1, 1935

By Ralph V. Stewart

"The asbestos orebody is contained within ultrabasic rocks of Precambrian age, being located in the continuous permafrost zone of the Quebec Ungava Peninsula, some 300 miles north of the tree line at approximate latitude 61'49' and longitude 73°58'.The asbestos deposit is at the western tip of a folded ultrabasic sill complex which trends northeast and covers an elliptical area 4.5 miles wide by 15 miles long. Locally. the asbestos occurs in. a completely serpentinized dunite rock. The principal rock types in the vicinity of the ore-body originally consisted of dunite, peridotite and pyroxenite, all of which have experienced at least two periods of alteration, so that no fresh rock now remains.The main ore zone in the open pit is approximately one quarter mile in length, 150 to 200 feet in width, and plunges at 25 to 30 degrees in a northeast direction below surface, to a vertical depth of at least 1,200 feet, Consider¬able tectonic activity resulted in favourable structural conditions which culminated in the formation of the ore zone in its present form.The deposit consists principally of cross-fibre ""gash type"" veins which vary in length from several inches to several feet. The principal fibre vein direction is parallel to the dip of the enclosing serpentinized dunite and sill complex.Some of the problems encountered during diamond drill¬ing in permafrost are briefly discussed."

Jan 1, 1976

"RÉSUMÉOn discute les principales sources de dilution au cours d’une exploitation souterraine. Les différentes définitions de la dilution en usage sont analysées. Une nouvelle méthodologie de calcul simplifiée et facile à utiliser dans la pratique minière est présentée. Cette méthodologie permet de remplacer les différentes expressions analytiques en usage par les deux facteurs de dilution seulement : un «facteur de dilution planifiée» lié à la sélectivité d’abattage au niveau de la planification minière et un «facteur de dilution additionnelle » permettant de juger de l’efficacité du contrôle de terrain et de la dilution pendant l’exploitation souterraine. L’application de cette méthodologie donnerait un outil nécessaire aux niveaux de la planification, du suivi des travaux d’exploitation et d’éventuelles études comparatives des coûts entre les différentes situations minières.ABSTRACTThe principal sources of dilution during underground evaluation and mining are discussed, then definitions of ore dilution currently in use are analyzed. These definitions vary depending on the authors. A new ore dilution evaluation methodology is proposed, replacing the ten different analytical expressions by only two: the planned dilution factor related to the stoping selectivity, done at the mine planning level, and the additional dilution factor related to the efficiency of the dilution control measures during stoping operations. The conclusion shows that the use of this methodology would be a definitive asset in planning, in stoping operations follow-up, and in future costs comparison studies between mining operations."

Jan 1, 2001

By G. M. Brownell

Introduction Within the past year a new deposit of gypsum has been opened up and brought into production in the Province of Manitoba. Until 1930, Manitoba&apos;s entire production came from Gypsumville, northwest of Winnipeg, at mile 161 on the Gypsumville branch of the Canadian National railway. However, during 1930 a gypsum bed was opened up at a point one mile south of the village of Amaranth, forty miles north of Portage la Paririe, on the west side of lake Manitoba (See Figure 1). Although no exposure has yet been discovered, the presence of gypsum below the surface in that district has been known for many years as the result of drilling for water. In 1929, J. R. Spear (1), of Winnipeg, interested some local capital in the possibility of .finding commercial deposits of gypsum, and, after some exploration work in the area with a well drill, the Amaranth deposit was located. Sixteen holes were put down at intervals of 400 or 500 feet, all of which encountered what appeared to be a continuous bed of gypsum, about thirty-eight feet thick, at a depth of 92 feet. The extent of the deposit has not yet been determined.

Jan 1, 1931

"The Crescent, DM, and Pothook zones are copper-gold porphyry deposits which formed in association with alkalic intrusions of the early Jurassic Iron Mask batholith. The characteristics of the Crescent and DM deposits are nearly identical. Both formed along the contact between the Cherry Creek monzodiorite and Pothook diorite phases of the batholith. Permeable intrusion breccias along the contact concentrated the flow of hydrothermal fluids. Early, pre-ore alteration is represented by pervasive, sulphide-barren potassium metasomatism. The precipitation of copper-gold ore occurred during subsequent fracture-controlled potassic alteration, and is most strongly developed in chlorite-sulphide veins and their alteration envelopes. A central zone of potassic alteration is surrounded by a propylitic, pyritic halo in both deposits. The DM zone is unique among alkalic porphyry deposits in its high abundance of quartz-sulphide veins.The Pothook deposit formed at the westernmost contact of the Iron Mask batholith with enclosing Nicola Group volcanic rocks. Pervasive potassium metasomatism, similar in style to that at Crescent and DM, is associated with intrusion of the Cherry Creek monzonite. Pervasive and fracture-controlled albitic alteration is associated with intrusion of the Sugarloaf diorite and introduced minor copper-gold mineralization. Most of the copper-gold mineralization was introduced during formation of veins and breccia matrices dominated by magnetite/hematite and sulphide. Late-stage chlorite veining may have remobilized or introduced additional gold mineralization.Copper and gold assays in the Crescent deposit are well-correlated and have a nearly constant Cu:Au ratio, suggesting that the metals coprecipitated during a single hydrothermal event. In the Pothook deposit, copper and gold do not correlate closely, lack spatial correspondence, and suggest that transport and/or deposition of the two metals were not identically controlled and that they may have been introduced at different times by separate hydrothermal events."

Jan 1, 1995

By Terence M. Gordon, Mati Raudsepp, Gregory M. Dipple

Four methods of measuring mineral abundance in a rock are examined for their potential in assaying for high-tech industrial minerals. One method uses X-ray powder-diffraction data and the other three rely on whole rock chemical data and information on mineral assemblages and mineral compositions. All four methods were employed to estimate wollastonite content in diamond drill core of skarn collected as part of an exploration program and are compared to visual estimates of wollastonite content from core logs. These techniques for assaying wollastonite span a considerable range ofaccuracy and expense, and combined, define a non-linear relationship between these variables. Accuracy increases rapidly relative lo expense up to total costs of about $50 per analysis. Assay methods in the $50-100 per analysis range have associated errors of 5-10% relative and probably suffice for most exploration programs. Improvements in accuracy above this level require a much larger investment. The most expensive assay technique (-$300 per analysis) yields the most accurate measurement of grade (relative error -1%). Its application may best be limited to periodic checks on other assay techniques and for fine-tuning ofmineral separation procedures.

Jan 1, 2001

By T. Motegi

Semisolid casting provides grain refinement of the cast structure and prevents macro-segregation. The conventional semisolid slurry is obtained by electromagnetic or mechanical stirring. In our process, the magnesium alloy (AZ31) slurry is made using an inclined cooling plate instead of the conventional methods. The slurry obtained is cast into a twin-roll caster and makes a continuous sheet of 2 or 3 mm thick. The most important factors that influence the sheet casting are the casting temperature and twin-roll speed.

Jan 1, 2007

By J. L. Gartshore

PRACTICALLY all of Quebec's chrysotile asbestos production derives from twelve mining and milling operations located in the "Eastern Townships" area of the province. The annual output of these twelve operations exceeds one million tons of chrysotile asbestos, valued at over one hundred million dollars, and is shipped to manufacturers spread over all six continental areas of the world. A total of approximately twenty million ton of asbestos ore yearly, or about seventy-five thousand tons a day, is mined. Individually, the operations vary in size from about two thousand tons to thirty thousand tons per day. Removal of waste rock and overburden to develop these ore tonnages varies greatly from one mine to another, but would probably average out at about a one to one ratio.

Jan 1, 1962

By J. W. Reynolds

Introduction The Sullivan mine, at Kimberley, B.C., is the principal source of ore for the Consolidated Mining and Smelting Company of Canada, Limited. Current production amounts to about 2,500,000 tons of lead-zinc ore a year. With approximately 1,600,000 feet of percussion drilling and 700,000 feet of diamond drilling being carried on each year, any improvements in drilling practice are important. Testing of new equipment and drill bits is a major function of the Testing Department at the mine. Tungsten carbide bits have been the subject of many tests since 1947 and have been used in operations since 1948. This paper details with the methods of testing and gives comparative data on performance and costs for tungsten carbide bits as compared to steel bits. Operational use of tungsten carbide bits started in April, 1948, and the extent of application has increased considerably since that time. The scale of employment is illustrated in Table I, which also shows other statistics on the use of carbide bits. Up to the present time eighteen types of carbide bits or tipped steel, as made by six different manufacturers, have been tested. In general, one supplier&apos;s bits have been used in operations, but some large-scale operational tests have been carried out with other types. The types tried are shown in Table II. To date they have been, the subject of 33 tests, covering the destruction of 804 bits over an observed footage of 42,586 feet.

Jan 1, 1951

By R. L. Every, A. G. Fonseca

"Sulphur deposition on the internal wall of a pipeline is caused by the temperature effect on the solubility of sulphur in the carrier fluid and is not due to particulate sulphur present. Deposition can be completely eliminated by proper insulation of the pipeline to prevent ""cold-spots"" and the resultant temperature gradient necessary for sulphur to precipitate from solution. Friction head losses for sulphur-condensate slurry systems are quite acceptable from a technical and economic standpoint and, in fact, are less than many present commercial slurry systems. Slurry transportation of sulphur in a hydrocarbon pipeline is a viable possibility and promises to have economic advantage over currently accepted transportation modes."

Jan 1, 1972

By F. Daniel Rosenkranz, Peter L. Silveston

Experiments investigating the treatment of a ground wood white water waste from an Ontario pulp and paper mill by an HVCB coal are reported. Adsorption capacity for the waste, with a soluble COD contribution of 2,100 mg/I, amounted to 0.17 per cent, by weight, of the Nova Scotia coal used. Percolation of the white water waste through a coal bed indicated that soluble COD is removed. For finely ground coals, over 90 per cent of the suspended solids in the waste are retained on the coal. Plugging of the coal bed is rapid, so that any treating process using filtration would have to renew the surface of the bed frequently.

Jan 1, 1970

By Lawrence Nordell

A Conjugate Anvil-Hammer Mill (CAHM) has the potential to replace conventional crushers and SAG mills, with their respective conveyors and stockpiles, in a SABC circuit. It may improve comminution circuit efficiency by 100%. CAHM compresses rock in a more efficient way, similar to 19th century stamp mills, which follows the fundamental research of Schönert (1990 & 1996). CAHM efficiency is being proven through the use of ROCKY (2011) Discrete Element Method (DEM). ROCKY features allow it to simulate realistic comminution. CAHM is customizable with many geometries that are rock-property specific. ROCKY?s wear modeling compliments the structural integrity of the design.

Jan 1, 2012

By Earle J. Klohn

"The design, construction and operation of tailings dams is rapidly becoming a major consideration for most new mining developments, as well as for many existing operations. In North America, under pressure from public opinion, various government agencies have in recent years enacted legislation covering the design, construction and operation of tailings dams. In British Columbia, comprehensive legislation has been passed during the past year (1971). All of these new regulations may be placed into two broad categories: regulations concerning the safety of the dam and appurtenant structures, and regulations concerning the prevention of pollution. Both types of regulation affect the design of the tailings dam facilities. Consequently, they must be considered jointly by the designer. A good tailings dam design must satisfy the basic requirements of safety, pollution control, storage capacity and economy. To achieve this, 'the design must be based on a thorough understanding of both the geotechnical problems involved and the requirements of the mining development. Obviously, this requires close cooperation between the designing geotechnical engineers and the mining operators. This paper outlines the major engineering factors that should be considered in the investigation, design, construct ion and operation of tailings dams. Basic methods of tailings dam construction are reviewed and the advantages and disadvantages of each briefly discussed. Comparisons are made between the design and construction of conventional water supply dams and tailings dams. Examples are presented of some of the problems that may arise during construction and operation of a tailings dam. The paper also explains the need for basic instrumentation of tailings dams and for carrying out simple field tests and measurements during construction and operation. Of prime importance is the downstream monitoring of surface and subsurface seepage flows. These observations are invaluable where contamination of surface and/or subsurface water may become a contentious issue at some future date. Each tailings dam design must be based on a study of the particular requirements of that project. To make a proper evaluation, adequate data must be available concerning a large number of items•, including such things as: topography, hydrology, geology, subsoil properties, seismicity, government regulations, fineness of mill grind, mill water balance, availability of suitable construction materials, volume of water to be stored behind starter dam, downstream development or liability, and many others. The large number of variables involved in such an evaluation often result in the designer considering two or more alternative designs. Selection of the final design, which is usually based on detailed cost analyses of the alternatives, must be made in close consultation with the owner."

Jan 1, 1972