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By W. R. McClelland

GOLD-BEARING ores, representing many types, are found widely distributed through the Province of British Columbia. They range from those which by their nature may be considered as complex, to those whose mineral characteristics are simple. Those in which the gold is associated with metallic sulphides provide particular milling and metallurgical problems, the solution of which involves not only detailed laboratory investigation but also a careful consideration of economic factors. The location of an ore-body may have a deciding influence on the adoption of a method for the metallurgical treatment. Whether the ore should be treated with the object of recovering the gold as bullion or as a shipping concentrate is often dependent on such topographical considerations as the position of the mine at or near tidewater or within a reasonable overland distance of a smelter. British Columbia is fortunate in having the Trail smelter situated in the southern part of the Province, and the smelter at Tacoma, Washington, is accessible for coastwise traffic. Both of these provide a ready market for most types of gold-bearing concentrate. In order that the results obtained by laboratory tests may give a fair indication of what should follow in mill operation, it is essential that the test sample should represent as closely as possible in mineralogical character and in grade the ore that eventually will constitute the feed to the mill. In the early stages of mine development this consideration is sometimes overlooked and samples of a much higher grade than would be representative of run-of-mine ore are submitted. Flotation tests on such a sample of ore high in sulphides may show a low ratio of concentration, bu.t if the actual run-of-mine ore is lower in sulphides the mill operation will reveal a much higher ratio. The recommendations for treatment based on the results of laboratory tests may have been against concentration, when in actual operation this would be the most suitable method of treatment. Recommendations based on laboratory tests are necessarily from the results of work carried out on the sample submitted, modified only by such other economic or topographical information as may be known to the investigator. This paper deals with a few of the gold ores found in the six mining districts of British Columbia and is based on investigations made in the Ore Dressing and Metallurgical Laboratories of the Mines Branch, Department of Mines, Ottawa.

Jan 1, 1937

By Charles Camsell

At the Annual General Meeting of the Institute in 1924. I endeavoured to present the position held by the mineral industries in the commercial life of this country. The facts and figures were presented at that time in a detached way. Since then, however, I have made some attempt to analyze them in order to determine the causes for that position and to draw some conclusions as to the future of the mining industry. As everyone knows, our trade figures are very often used in political discussion, especially in discussion of tariff policy. It would be entirely out of order for me to say anything touching the tariff issue and I want to have it clearly understood that, in my opinion, the material I am about to present contains not a single statement or conclusion which anyone would be warranted in using as an argument for either a lower or a higher tariff or for tariff changes of any kind. As a starting point, let me re-state, very sketchily, Canada's general situation in external trade. In the last calendar year, 1924, we sold Canadian merchandise of all kinds to other countries to the value of $1,045,000,000 in round figures. Our purchases abroad reached about $893,000,000. Thus our sales exceeded our purchases by roughly $152,000,000. In other words, we had what is known as a 'favourable balance of trade' - one of the biggest favourable balances we have ever had in our history. The proceeds of our sales of Canadian products enabled us to meet the bills for all our purchases of foreign commodities and, in addition, placed a large surplus to our credit with which to offset our interest charges and other obligations abroad.

Jan 1, 1925

Mining Equipment Challenges Equipment Availability Unplanned downtime Maintenance Costs Secondary damage and catastrophic failures (T282 $750k) Emergency work is 4x the cost of planned work Inspections Troubleshooting time Incorrect repairs (parts, labor, lost production) Equipment Life Mis-operation of equipment

May 1, 2013

By D J. McDougall

Due to changes in the solid-state conditions of minerals in the rocks surrounding hydrothermal, contact meta-somatic or metamorphosed ore deposits, positive or negative thermoluminescent anomalies may be found in their vicinity. Several types of equipment which can be used for both quantitative and semi-quantitative measurements of the emission are discussed and compared. Methods of selecting, preparing and testing samples to ensure reproducible results are outlined, along with the kind of data which can be obtained from different types of equipment. The normal thermoluminescence of rock-forming min~ erals in the common rock types is noted, and variations in the solid-state conditions in the wall rocks which will cause marked increases or decreases of true thermoluminescence are outlined, as well as the thermolum-nescence-like emissions which are present in the vicinity of ore deposits. Introduction T HERMOLUMINESCENCE occurs when certain crystalline materials are heated to temperatures ranging between 180' and 400°C. The light emission can be ascribed to the release of electrons metastably trapped within the crystal lattice, with peak emissions taking place at temperatures which are more or less specific for a particular set of traps; the area under

Jan 1, 1965

"Under the term ""paleogeomorphology"" are grouped together all geo-morphological phenomena which are recognizable in subsurface geology. Since geomorphology is the science of the earth's relief features, paleogeomorphology is the science of buried relief features. Such features are of importance to the petroleum geologist whenever they lead to the trapping of hydrocarbons. In areas where these features abound -and western Canada certainly is such an area -pale-ogeomorphology ranks in importance with stratigraphy and structural geology as a hydrocarbon-finding tool. Hydrocarbons may be trapped either directly or indirectly due to paleogeomorphological processes. Both types of traps may occur either below the morphological surface or above (against) it. Several examples of types of paleogeomorphological traps are given. A new classification of geomorphological .features is proposed, with a subdivision into two main groups: constructive and destructive geomorphic processes. Of the many geomorphic classifications, some are of greater interest to the petroleum geologist in western -Canada than others. In the present paper the morphology of reefs and of buried erosional land forms are discussed in greater detail. In dealing with the reefs of the Devonian Leduc formation in Alberta, it is found that several groups of reefs can be distinguished and that each group presents a separate set of morphological characteristics. The effects of erosion and weathering are exemplified mostly in the Devonian, Mississippian and Jurassic of Alberta, Saskatchewan and Manitoba. Hydrocarbon traps occur below the highs on the erosional surface as well as in sands laid down in the lows of that surface. The rules which govern the formation of ancient landscape forms are worked out, using an area in southeastern Saskatchewan as an example."

Jan 1, 1960

By J. J. Laffin

In the pursuit of comfort and safety, the wonders of science have given us controlled heating and cooling, thus enabling us to enjoy all the aspects of present-day living to an extreme never previously •envisaged. Man's attempt to conquer the elements largely involves con-trolling the temperature around him. Without having conquered this aspect, his body energy would be consumed in trying to maintain physical comfort, rather than being invested in the explorations which have resulted in man's control over the forces of nature. The indirect methods used to obtain the most agreeable temperature environment were developed because of the natural tendency to strive for increased safety, convenience and comfort. Until the twentieth century, when heat generated by atomic fission became a reality, man's only source of heat, except for that of the sun, came from his discovery of fire.

Jan 1, 1962

By W. T. Martson

ABSTRACT Sooner or later, every producing mine faces the question of fill. This paper invites consideration of mill tailings as an economical, efficient, and quantitatively adequate source of such fill. Some of the advantages, disadvantages, methods of utilization, and methods of treating mill tailings for sand recovery are covered. ADVANTAGES AND DISADVANTAGES OF SAND FILL DISREGARDING economic com-promise, that material which supports the greatest applied load with the least compression is the best choice for fill. Table I, reproduced from U. S. Bureau of Mines Bulletin 60, is offered as evidence of the adequacy of hydraulically placed sand. Table II gives the results of tests made in an effort to determine the reason for the difference between load hearing qualities of dry-placed and hydraulically-placed sand. From these, it would appear that hydraulic placing gives a denser initial packing, with corresponding higher, and faster development of, load bearing qualities. Assuming this to be true, then if sand from mill tailings can be placed underground economically, it is the superior fill material. Table III summarizes cost data available. The most cursory glance through the available references (2, 5, 6, 7, 8, 9) will show .that the major benefit from the adoption of sand fill is a decrease in the non-productive fill ?cycle of a working place. This, it is estimated, increases the output of an individual stope by from 25 to 50 per cent. The advantage of reducing the number of required working places for a constant daily production is obvious.

Jan 1, 1951

By J M. Fletcher

The responsibility and scope of the Industrial Engineering Department, as organized at the Jeffrey mine, has been broadened to include any study, project or report that could result in more effective use of men, materials and equipment. Although still emphasizing wage incentives and co t reduction, much more varied work is now done, consistent with the in-.creased complexity of industry. Additional activities now include production, maintenance and inventory control improved job evaluation, packaging, labour utilization studies, technical sales liaison, mining, milling and service department n1ethods, plant layout, and specialized project analysis. Additional techniques include the extensive use of work .sampling and standard data. A recent trend has been toward increased emphasis on industrial relations, both in introducing change to the men and in providing requested explanations to Union stewards and officers. These new responsibilities have resulted in the development of specialists in some rather narrow industrial engineering fields, as well as the necessity for industrial engineering assistance in supervisory and job training.

Jan 1, 1963

By W. R. Cowan

The Caledon Outwash is a large deposit of glaciofluvial gravel and sand located 55 km north west of down town Toronto. For the most part it was laid down in a meltwater channel fronting the Paris Moraine about 14,000 years ago. Applying the braided bar model of Eynon and Walker (1974) the principal facies present are imbricated coarse gravels (bar corefacies); crudely stratified, imbricated bar top sandy gravels; and trough crossbedded side channel sands and gravelly sands. Of lesser importance are crossbedded bar front gravels, shallow braided stream facies gravels, and stoss side facies sands and pebbly sands (rare). Lithologically these deposits are characterized by FIGURE I. Geological relationships of Caledon Outwash. Industrial Minerals in Canada up to 95% Ordovician limestone and siltstone in the gravel fraction. A siltstone content of up to 34% requires that beneficiation be carried out for the production of better quality aggregates. Resources remaining are estimated to exceed 500 million tonnes in 3000 ha of the most suitable part of the deposit. Present production is about 4.5 million tonnes per year, shared by several producers.

Jan 1, 1984

By R. W. Coburn

The results of field experiments on wells which required stimulation indicated that engineered well-completions will cause an increase in ultimate recovery at reduced costs. Techniques and tools have been developed which can be used to establish well conditions most conducive to successful stimulation. Cementing, perforating and treating are bound together so completely that the success of one phase is completely dependent on the .effectiveness of the preceding phase. A method of determining the efficiency or effectiveness of any given well-stimulation treatment has been derived. Pressure behaviour during a treatment can be analyzed to yield the total percentage of the formation which has been treated.

Jan 1, 1960

The integration of mining and mineral processing technologies into new advanced mining systems is considered to offer several benefits, including selective mining, reduction in waste, increased productivity, flexibility, and improved resource utilization. This paper focuses on underground hardrock mining and the integration of pre-concentration technologies into future mining systems as representing realistic, shorter-term integration options. Control of fragmentation to optimize grinding, pre-concentration of ores, in situ leaching, and modular mining/mineral processing systems are possible with existing technology. Current research is directed toward development of integrated underground systems that minimize surface activity and minimize or eliminate surface waste disposal. Results from a simulation model of an integrated underground pre-concentration system are presented.

Jan 1, 2002

By H P. Tardif

This paper briefly describes some of the phenomena encountered when materials are submitted to extremely high pressures, such as those produced by the detonation of an explosive charge placed in contact with the material. It was found that extensive changes take place in the? microstructure of iron and steel. Diffusion-controlled processes, such as the transformation of lamellar pearlite, the recrystallization and grain growth of ferrite, and the homogenization of the pearlite-ferrite structure, can take place within micro-or milliseconds. Mechanical twins can propagate without deviation from ferrite to pearlite, thus indicating a proeutectoid ferrite-pearlite-ferrite orientation relationship. The propagation and interaction of intense stress waves in materials was demonstrated with the use of Armco iron. Finally, a comparison is made of the damage produced in metals by the formation of craters made by explosive shock and by hypervelocity impact. D DRING the last few years, exceptional development has taken place in the field of explosive metallurgy, i.e., the

Jan 1, 1964

"Developing markets for western metallurgical coal have continued to stimulate considerable exploration activity in the Rocky Mountain foothills and to influence major segments of a wide-ranging carbonization R&D pro-gram. Adjunct studies have included expanded petrographie investigations.Coal preparation has• been principally directed toward utilization of prepared small coal and was, like much of the year's combustion work, strongly influenced by concern over atmospheric pollution. Particular attention has been given to desulphurization and to the suppression of pollutants in combustion systems.In the area of non-fuel utilization of coal, interest has centered on plant nutrients and on a series of coal-based carbons which, inter alia, possess utility as filtration media.Other projects included the development of improved sampling and analytical methods, investigations into the effect of storage on coal proper-ties and R&D in solids pipelining. In addition, a significant volume of basic 'uncommitted' research has been maintained."

Jan 1, 1968

By G. S. Hume

In the transformation of carbonaceous materials, such as peat, to coals of various grades, the changes are known to be both physical and chemical and the grade of coal finally produced depends on the stage to which alteration proceeded. Those changes, which are frequently spoken of as the results of metamorphism, are due to pressure with accompanying heat and, according to the amount of metamorphism to which the sediments with the included carbonaceous beds have been subjected, there is a gradation from peat to anthracite coal, and even to graphite. The improvement in the quality of the coal as a result of metamorphism is due to an increase of the carbon content of the coal and a corresponding loss of the volatile materials. This rise in the quality of the coal according to the degree of metamorphism is well illustrated by the coals of western Canada. In the Plains area, where the deformation and the attendant metamorphism of the sediments is comparatively small, the coals are lignites, whereas in the mountains, where deformation has been severe, the coals are semi-anthracites. Sub-bituminous and bituminous coals occur in the intervening areas. The same general relationship between the quality of the coal and the degree of metamorphism holds true for the Appalachian basin of the United States, where there is a progressive improvement in the quality of the coals from west to east, that is, from an area of comparatively slight metamorphism to an area of marked deformation in the Appalachian Mountain region. But while it is true that this relationship holds in a general way, it has been found that the improvement in the quality of the coal is not always uniformly progressive, and there may be local variations such that an area containing coal with a carbon content indicating low or medium metamorphism may be surrounded by areas in which the coals are of higher grade. These local variations in many cases can be explained, and they in no way detract from the general rule that, in a region exhibiting a progressive betterment in the quality of the coal from an area of low metamorphism to one of more marked deformation, the quality of the coal, i.e., the amount of fixed carbon in the coal, may be taken as an index of the degree of metamorphism of the coal as well as of the sediments in which it occurs, It has been pointed out (') that certain coals, such as cannels, are unreliable indicators of the varying degree of metamorphism because of the nature of the material from which such coal was derived. Such coals, however, are not known in western Canada and their behaviour need not here be discussed.

Jan 1, 1927

By C. Díaz, M. Barati

Prof. Torstein Utigard's untimely death, in the spring of 2012, put an abrupt end to a meritorious career in the field of high temperature chemical process metallurgy. As an academic in the Department of Materials Science and Engineering of the University of Toronto, Torstein made solid contributions to the advancement of knowledge pertaining to production and refining of both nonferrous and light metals, and to the development of inquisitive and innovative young people in extractive metallurgy. In this profile, the authors highlight aspects of Torstein's rich personality and of his contributions to his field of expertise.

Jan 1, 2015

By Nicholas C. Williams

This paper presents the development of a demand reduction and responsive strategy capable of reducing the electrical power demand, particularly during peak conditions. The work presented includes a case study of a UK colliery. Areas explained are the equipment installation at the mine; the development of the demand reduction strategy including the load profile database and prediction optimisation model. Some live production data from the power meter installation at the mine is also presented.

Aug 1, 2013

By C. M. Clapperton, K. E. Darke, A. J. Boyce, C. M. Rice, S. D. Redwood

"The Kori Kollo gold deposit is hosted by a c.15 Ma sericitized dacite stock in the LaJoya district on the Bolivian Altiplano. The mineralization is of the Bolivian polymetallic vein(BPV) type, with a signi?cant amount of the gold reserves contained in the oxide cap.Field and microscopic studies, K-Ar dating, ??34S values of pyrite, alunite and jarosite, and ??18O values of alunite and jarosite demonstrate that some of this gold is supergene. Two types of supergene gold are present: minute gold grains, 1 to 10 microns across, of high fineness and associated with jarosite and iron oxy-hydroxides; and ‘invisible’ gold, which is probably sorbed onto minerals such as jarosite and iron oxy-hydroxides.Pyrite ??34S values fall in the limited range -3.5 ± 0.6‰, consistent with a magmatic origin. Sulfate ??34S values are homogeneous and overlap closely with those of pyrite (-1.2 ± 2.1‰), which supports petrographic evidence that sulfates replaced pyrite. By contrast, sulfate ??18O values are inhomogeneous with a large range (alunite +2 to 26‰, jarosite -5 to +18‰). These data are interpreted as reflecting kinetically controlled reactions involving various proportions of atmospheric oxygen and local meteoric water. This is typical of supergene alteration and is due to the seasonally dry climate of the Altiplano.The oxide-zone mineralogy is dominated by sulfates and iron oxy-hydroxide minerals with some phosphates and halides, which indicates that the groundwaters were acidic, oxidizing and relatively saline. Under these conditions the most likely complexes responsible for gold mobilization are halides.Geological data and K-Ar ages indicate that oxidation of the BPV deposits began at least around 11 Ma and possibly up to 15 Ma ago, and that supergene alteration lasted until around 4 Ma. During this period, erosion was minimal. Although supergene processes have been active on the Bolivian Altiplano since the Middle Miocene, in contrast to Northern Chile, enrichment of gold has not occurred."

Jan 1, 1997

By C. M. Clapperton, K. E. Darke, A. J. Boyce, C. M. Rice, S. D. Redwood

"Abstract - The Kori Kollo gold deposit is hosted by a c.15 Ma sericitized dacite stock in the La Joya district on the Bolivian Altiplano. The mineralization is of the Bolivian polymetallic vein (BPV) type, with a significant amount of the gold reserves contained in the oxide cap. Field and microscopic studies, K-Ar dating, ??34S values of pyrite, alunite and jarosite, and ??18O values of alunite and jarosite demonstrate that some of this gold is supergene. Two types of supergene gold are present: minute gold grains, 1 to 10 microns across, of high fineness and associated with jarosite and iron oxy-hydroxides; and ‘invisible’ gold, which is probably sorbed onto minerals such as jarosite and iron oxy-hydroxides.Pyrite ??34S values fall in the limited range -3.5 ± 0.6‰, consistent with a magmatic origin. Sulfate ??34S values are homogeneous and overlap closely with those of pyrite (-1.2 ± 2.1‰), which supports petrographic evidence that sulfates replaced pyrite. By contrast, sulfate ??18O values are inhomogeneous with a large range (alunite +2 to 26‰, jarosite -5 to +18‰). These data are interpreted as reflecting kinetically controlled reactions involving various proportions of atmospheric oxygen and local meteoric water. This is typical of supergene alteration and is due to the seasonally dry climate of the Altiplano.The oxide-zone mineralogy is dominated by sulfates and iron oxy-hydroxide minerals with some phosphates and halides, which indicates that the groundwaters were acidic, oxidizing and relatively saline. Under these conditions the most likely complexes responsible for gold mobilization are halides.Geological data and K-Ar ages indicate that oxidation of the BPV deposits began at least around 11 Ma and possibly up to 15 Ma ago, and that supergene alteration lasted until around 4 Ma. During this period, erosion was minimal. Although supergene processes have been active on the Bolivian Altiplano since the Middle Miocene, in contrast to Northern Chile, enrichment of gold has not occurred."

Jan 1, 1997

By Y. Gordon

ABSTRACT A methodology based on a two-stage approach was developed for process technology selection. The first stage includes evaluation of available technologies, followed by shortlisting the best technologies based on mass and energy balance modelling, financial analysis, and risk analysis. The second stage involves detailed analysis using refined input data, mass and energy balance modelling, and capital and operating cost estimation, as well as a more detailed financial analysis. A case study covering the selection of ironmaking technologies for a company in the Russian Federation is presented to illustrate the critical elements of the methodology and the analysis process.

Jan 1, 2014

By Donald Carlisle

"IntroductionTHE OPINION is held by many persons outside the mining industry, and by some within it, that mine •operators customarily find it advantageous to mine •only the richer parts of orebodies and to leave behind, perhaps permanently, leaner material which could be mined only at a lesser profit. This opinion and the inference which might be drawn from it that 'gutting' of mineral resources is a common feruture• of the mining industry are prejudicial to the intertsts of the industry and deserve careful scrutiny. Oddly enough, a theory of mine economics which gives much support for the opinion was advanced first by members of the mining profession itself, has been repeated •several times in mining literature, and to my knowledge has never been adequately refoted.According to the theory, selective mining of the rich ore first on a large scale will yield substantial gains and these gains do not merely reflect the desire of 'money minded investors' for a quick return but derive from the logical application of compound interest rates and the concept of ;present value. W. O. Hotchkiss and R. D. Parks (1) illustrate the reasoning with a hypothetical example in which an orebody of 4,000,000 tons may be mined either in its entirety in forty years at $1.00 per ton profit or selectively with the recovery of only the richest half in twenty years at $1.50 per ton profit. They show that, with Hoskold rates of 4 and 8 per cent, the present value of profits from mining only the richer 2,000,000 tons exceeds the present value of profits :from mining the whole orebody by about 20 per cent."

Jan 1, 1953