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By Victor F. Hollister

Although none of the deposits discovered to date are of commercial interest, significant Frasch or sedimentary sulphur deposits occur in Nova Scotia in Upper Mississippian Windsor Group evaporites. The evaporite sequence contains anyhdrite and is overlain by impervious shales. It also is •mderlain by locally petrolijerous formations that are potential hydrocarbon sources for reaction with anhydrite to produce sulphur. As well, stratigraphic and structural traps are known to exist in the Mississippian beds. Thus, all requisites for sedimentary sulphur genesis are present. Available hydrocarbon sources are numerous but small; resultant sulphur deposits therefore are probably also small. Evidence suggests, however, that sulphur deposition is not yet complete.

Jan 1, 1984

By F G. Cooke

"This paper describes a medium-sized copper mine's results in making innovations and changing operational practices to combat increasing expenditures due to higher labour and supply costs, extended workings, scarcity of experienced manpower and problems created by deteriorating ground conditions.OPEMISKA COPPER MINES (QUEBEC) LIMITED is located at Chapais in the Chibougamau area, in central eastern Quebec, approximately 300 miles north of Montreal and 150 miles north west of Lake St. John. The latter area, developed by lumbering and farming, has supplied the majority of the employees, who, with training and experience and a desire to work and improve themselves, have become the backbone of the Company's 600 personnel.Opemiska began production in 1954 at a rate of 400 tons per day, using diesel power and road transportation. The rate was progressively increased and, by 1959, with hydro-electric power and rail transportation, the mine had reached its present production rate of 2,000 tons per day. It has produced concentrates containing over 430 million lbs of copper."

Jan 1, 1968

By Hector Monette

"AFTER SPENDING a lifetime in the mining industry it is normal that one should be concerned with the future of his profession, especially if he is directly responsible for the education and formation of future mining engineers. It is not necessary to insist on the importance of mining for Canada and for the entire world to prove the necessity of the Mining Engineer. A statement was made by Zay Jeffries, former vicepresident of General Electric Co., and here I quote: ""Even though minerals without man are of no moment, man would not be man as we know him without minerals ... ""minerals are as essential to the life of social man as food is to man himself"". This certainly expresses magnificently the purpose of the mining profession. These are the reasons why I have accepted to present my views on the future of the Mining Engineer. If I express some concern it is not because I feel that there is any danger for the profession to disappear; men will always respond to a challenge and this can be found in the extraction of minerals as well as in any other field of human endeavour. However, the first big question concerns the competitive position of Canada in the world of mining. To be made available to Canadians and to the rest of the world, all this tremendous potential mineral wealth that our country has been so generously endowed with by nature must be gained from the earth's crust at a competitive cost. Otherwise it will never become ore and will have no value. Let us not forget that although minerals are discovered, mines are not found but are made. So let us be more efficient mine makers. To accomplish this end, it is the duty of the different responsible organizations at all levels - be they governmental, para-governmental, public or private institutions - to do their utmost to assure the profitable development of our mineral wealth. The University has an all-important role to play in preparing all the specialists required by this intricate machine that mining is. All the different disciplines of engineering, health, social and -managerial sciences are needed for the good functioning of the mining industry. Although they are all essential, some will play a more important role as a member of the structure. In this discussion it is the role of the most important member, the mining engineer, who is actually responsible for the extraction of the minerals from the earth's crust that must be established. From this we will then be able to analyse his responsibilities and try to suggest the mining engineering program most suitable to prepare this engineer for his future role."

Jan 1, 1972

By F. R. Archibald

MR. A. F. B. Norwood: Having been associated in the past few years with nine different plants roasting aurif erous concentrates in Australia, two of which were new installations for which design and construction were undertaken by the writer, I read Mr. Archibald's paper with very great interest, and I deem it a great privilege, as a member of a sister Institution, to be invited to contribute to the discussion on the paper. I wish to congratulate the author on a very informative and interesting paper, and, although situated many thousands of miles away, I feel I have gathered from it a very close idea of the operating conditions and of the work that has been carried on at the Beattie gold mine. Working along somewhat different lines, it is interesting to note that the conclusions drawn by the author run closely parallel to those accepted in Western Australia, viz., that the object of roasting is to obtain a porous calcine, and that this can best be achieved by roasting first at a temperature below 900 deg. F. to 1,000 deg. F., and then raising the temperature at the finish of the roast. Turning first to the laboratory work, the materials I have studied in Western Australia cover a range from those with little or no arsenic to concentrates carrying as high ?as 20 per cent, i.e., even higher than in the analysis quoted for the eoncentrates from Nepheline Products, Limited. In the ease of arsenic-free pyrite concentrates, the roast is ideally carried out at a temperature ranging from 900 deg. F. to 1,000 ferric oxide is one cause of the refractory gold remaining In deg. F. No improvement in extraction is obtained when the calcines are cyanided by raising the final temperature above this point; nevertheless, in technical practice it is desirable to finish the roast at 1,200 deg. F. in order to decompose basic ferric sulphate and thereby reduce the consumption of chemicals in the subsequent cyanidation step. However, if at any stage of the roast the temperature is raised above 1,200 deg. F., the extraction by cyanidation falls, and continues to do so the higher the maximum temperature that is reached. Line A in the accompanying graph typifies this effect.

Jan 1, 1949

By R. D. Brown

Higher employer costs and increased employee benefits will result from the current sweeping revisions of the un-employment insurance system now receiving consideration before Parliament. The new legislation, the Un-employment Insurance Act, 1971, will substantially increase the unemployment insurance costs of many employers through an increase in the level of employer contributions -generally, employer contributions will go to 1.4 times employee costs -as well as by extending coverage to many classes of employees now exempt. Under the new legislation, executives, technicians, teachers, institutional workers and others will be covered, and eligible for the higher benefits which it provides. For the first time, absence from work because of illness or accident may qualify individuals for unemployment insurance benefits.

Jan 1, 1971

By T. Gerritsen, R. MacRosty, R. Pula

For several years Hatch has been installing fibre optic temperature sensors on the copper cooling elements of smelting furnaces to improve monitoring capabilities in critical locations. The metal/matte tapblock is a key area to monitor in the furnace as it undergoes severe wear from the molten material repeatedly drained through it. The high wear rate around the tapblock means downtime is necessary to perform refractory repairs. A good understanding of the tapblock condition allows the operation to maximize safety and production; consequently the metal/matte tapblocks have been the focus of this study. Fibre optic technology allows the installation of numerous sensors in locations that are very sensitive to refractory thickness, thereby providing information previously unavailable with traditional measurements. The transient nature of the thermal response to tapping and the three-dimensional geometry of the tapblock confound the interpretation of refractory thickness from temperature measurements. This paper focuses on the analysis of both plant data and thermal modelling simulations and details the progress made in relating the temperature measurements to the refractory thickness in front of the copper tapblock.

Jan 1, 2014

By P Kovacs, D. L. Flock

For the purpose of reservoir-performance calculations a balance can be made between the materials with-in the reservoir and the production from the reservoir. The material balance equation, a relationship which holds under or near equilibrium conditions, has been used in many forms by the Petroleum Engineer for the determination of initial oil-in-place in the reservoir and the calculation of performance into the future. One of the more recent methods developed by Tracy, utilizes a modified form of the Schilthuis material balance. In the latter case, values of incremental production are assumed for a particular pressure drop, a value of the gas-oil ratio found and a check of this estimate made by calculation"' the initial oil-in-place. Tracy's method utilizes an estimation of the instantaneous gas-oil ratio and by trial and error a value of the gas-oil ratio is

Jan 1, 1961

By R. E. Eyre, L. P. Landucci

C URRENT practice in the zinc concentrate roasting plant of The Consolidated Mining arid Smelting Company of Canada Limited, at Trail, B.C., involves passing the furnace effluent gases through an electrostatic precipitator for the recovery of dust. After removal of the dust the gas is treated for recovery of sulphur dioxide by conversion into sulphuric acid ( 1). However. as roasting techniques improved, and furnace productivity in-creased, the rated capacity of the precipitator was exceeded and it was necessary to consider various means of improving the dust recovery. A study of methods indicated that a baghouse using silicone-treated glass fabric, might be suitable for this particular application. Glass fabric was chosen because the temperature of the roaster effluent gases would range from 450°F to 500°F and tempering air was undesirable to avoid dilution of the sulphur dioxide gas.

Jan 1, 1962

By E. H. Kranck

Introduction Baffin Island is still too in-accessible to be of interest to the mining industry. However, twenty years ago few people dreamed of mining iron ?ore in Labrador. A journey by air to the most remote places in the Arctic is today no more remarkable than a trip to Europe, and the technical difficulties of mining minerals of high value are not insurmountable. Some ?observations concerning the geology and mineral possibilities of Baffin Island, the largest of the Arctic islands, may therefore interest the members of the Institute, in spite of problematic practical value of the subject. The following short account is mainly based on observations made during the Baird Expedition of the Arctic Institute of North America last summer 1950), and on information available from earlier expeditions. Early Work Baffin Island was one of the first parts of Canada to attract prospectors. Frobisher sent a shipload of rocks, which he believed contained precious metals, from Baffin Island to England. This attempt, however, was a failure and no further serious prospecting work has, so far as I know, been done. During the past few years geological mapping has been carried out by the Geological Survey of Canada (Fortier. Davison, 1949-1950) in the southern parts ?of the island, along the coast of Hudson strait. In 1942, Weeks mapped the coast from Pangnirtung to the head of Cumberland fiord, and Netteling river up to Netteling lake. In the northern parts of the island, only scattered observations have been made ?by Bell, Watkins, Baird, and others.

Jan 1, 1951

By F. Habashi

"The rare earths industry started in Austria in 1887 by Carl Auer von Welsbach (1858-1929) Professor of Chemistry at the University of Vienna. The process was based on monazite sand transported from Brazil as shipping ballast free of charge. This made possible producing thorium, cerium, and other rare earths at a low cost, thus permitting the growth of the industry. However, once the Brazilian authorities realized the strategic importance of the sand, shipping was stopped. Brazil then started its own processing of the sand in 1949. The background for Auer’s work, the role of Robert Bunsen in Heidelberg, and the invention of the spectroscope will be presented. INTRODUCTIONHeidelberg on the Neckar (Figure 1) was the meeting place for chemistry students from all over Europe in the nineteenth century. Her university founded in 1386 had already a famous professor of chemistry and medecine in the Faculty of Medicine by the name Leopold Gmelin whose three - volume Handbuch der theoretischen Chemie appeared in 1817-1819, that became later a multi-volume monumental work. As successor to Gmelin came Robert Bunsen (Figure 2) in 1852 who made this university town the Mecca of chemistry students. One of his students, the English Henry Roscoe (1833-1915) who became later a distinguished professor in Manchester, described him as follows: ""As an investigator he was great, as a teacher he was greater, as a man and a friend he was greatest""."

Jan 1, 2012

By W. W. Beaton

The Coxheath copper mine is situated on the north side of the Coxheath hills and opposite the French Vale, at a distance of about 10 miles southwest of Sydney, Cape Breton county. The deposit was discovered in 1880, and the first work on the property was carried out with local capital. Lacer some Boston men became interested and formed a Company to finance the undertaking. This group operated the mine intermittently for approximately 20 years, spending close to one million dollars on the undertaking. Three shafts were sunk to depths of 110, 190, and 340 feet, and further underground workings to the extent of approximately one-half mile were driven. Also, an extensive surface programme was carried out. in which many test pits and hundreds of feet of trenches were dug, Early in the summer of 1928 the Arno Mines, Limited, optioned the property and immediately started an exploration campaign. A series of trenches were dug along the parallel vein system, and over 4,000 feet of diamond-drilling was done. The results obtained were so encouraging that a mining plant was erected in the fall of chat year and No. 2 shaft was drained. A complete new plant was installed, consisting of one 120 h.p. Fairbanks-Morse Diesel engine, direct connected to a Sullivan angle compound, air compressor; an 80 h .p. Leonard boiler, which supplies power for the 7 by 11 Ingersoll-Rand hoist; and a Sullivan class C steel sharpener and oil furnace. Two 250-gallon Cameron pumps, one operated by steam and the other by air, were placed in the mine so that, in case of a break-down, the mine would not be flooded.

Jan 1, 1930

By Jan W. Merks

The objective of metrology in mineral exploration is to derive unbiased confidence limits for masses of metals contained in reserves and resources. Sets of test results for gold and silver determined in pairs of interleaved bulk samples give unbiased confidence limits for the central value of each metal. The same sets of test results show how to verify spatial dependence by applying Fisher?s F-test to the variance of a set and the first variance term of the ordered set. A significant degree of spatial dependence gives a higher degree of precision for the central values of gold and silver. Plotting variance terms of an ordered set against the variance of the set and its lower limits of asymmetric 99% and 95% confidence ranges gives a sampling variogram. Sampling variograms put in plain view where spatial dependence in sampling units or sample spaces dissipates into randomness. The application of statistical methods to test results for sets of ordered core samples within boreholes, and for sets of ordered ore volumes within profiles, plays an important role in defining reserves and resources.

Oct 1, 2009

By J. Guha, D. Racicot, S. Peloquin, F. Lange-Brard, S. Bureau, A. Tremblay

The Devlin copper deposit consists of a flat-lying vein and a network of steeply dipping mineralized veinlets hosted by leucotonalite of the Chibougamau Pluton. Most of the vein is enclosed in a hydrothermal breccia zone which has been superimposed on a primary igneous breccia formed during the emplacement of the leucotonalite unit. This igneous breccia contains cognate fragments as well as fragments of the Dore Lake Complex, host rock to the pluton, set in a leucotonalite matrix. The hydrothermal breccia is formed of fragments of leucotonalite and the earlier breccia set in a matrix of finely comminuted rock variously altered in a roughly zonal arrangement. The major ore-bearing structure is the tabular flat-lying vein, varying in thickness from 10 centimetres to 1 metre, with a slight dip to the northeast. Well developed fracture planes, in four major orientations, contain both sulphides and gangue minerals. These appear to be displaced by the flat-lying vein. Late movements affecting the deposit include minor vertical displacements and an east-west shear truncating the southern edge of the vein. Widespread selective alteration of the leucotonalite, followed by multiple alteration veining stages characterize the deposit. Fluid inclusions associated with the mineralization indicate low temperatures, variable salinities with a variety of daughter minerals, and a vapour dominated phase. The fluid shows evidences of boiling at shallow depths. The sequence of events envisaged for the Devlin deposit is a primary brecciation during emplacement of the leucotonalite unit with widespread selective alteration possibly during the cooling stages followed by hydrothermal brecciation and late stage fract uring producing the vertical fractures and the flat-lying vein. From the alteration characteristics and the fluid data it is inferred that the Devlin deposit is the near-surface expression of a porphyry system.

Jan 1, 1984

By J. A. Pigott, R J. Hall

The International Nickel Company of Canada, Limited operates five underground mines on the rim of the Sudbury Basin in the northern part of the Province of Ontario. Four of the mines, the Frood-Stobie, Creigh-ton, Murray and Garson, are located on the south range of the basin with-in a radius of IO miles of the centre of the city of Sudbury. The fifth mine, Levack, is on the north range about 30 miles northwest of the city. The ores are mined primarily for nickel and copper, and the principal minerals are pentlandite, chalcopyrite and pyrrhotite. In 1960 the total ore production was in excess of 16 mil-lion tons, 95 per cent of which was produced from the five underground mines and the balance from the Frood-Stobie Open Pit. Mining at this open pit is nearing completion and underground production has been expanded to replace the open pit tonnage.

Jan 1, 1961

By D. Brisebois, J. M. Fecteau, S. Poirier

"This paper focusses on new developments regarding thermal rock fragmentation applications. The technology consists of a strong burner powered by diesel fuel and air. The thermal reaction that is created allows for the enlargement of 125 mm to 450 mm holes by breaking the rock in a spalling effect. It has been used for over 30 years in Russian open pit mining. Following an agreement between Dynamitage T.C.G. Inc. and the owner of the technology, major improvements have been brought to this technology, allowing for the fabrication of a prototype suitable for the Canadian industry. In Russia and the Ukraine, thermal rock fragmentation is actually used to drill large diameter holes in surface mining. Upon having acquired a better knowledge of this technology, it seems that it presents a great potential for selective mining in narrow-vein operations, for either surface or underground mining.Rocmec International Inc., a subsidiary of Dynamitage T.C.G. Inc., and Natural Resources Canada are technical partners in the evaluation of the operational parameters and environmental aspects such as gas, heat, dust and fog emissions. Furthermore, Canada Economic Development is a financial partner in this project.This paper presents the technology and its history. It also reports on the changes brought to the equipment to adapt it to North American environments. A summary of the tests carried out since 1995 is provided, along with the main conclusions obtained. The anticipated applications for the use of this technology in both surface and underground environments are described such as open pit mining, bulk sampling and narrow-vein ore extraction. An estimate showing a comparison between the thermal fragmentation mining concept and the long-hole mining method is presented and, finally, the future developments planned are listed."

Jan 1, 2003

By L. Connolly, F. R. De Luca

"Rubber liners at Denison Mines Limited are used in 10 1/2x 24' low discharg0 pebble mills. These were originally 10 1/2 x 13 Dominion overflow type ball mills. Experience here shows that the wear of rubber and ni-hard lifters is approximately the same in the feed end half of the mill, while the wear of rubber lifters is much greater in the discharge half. The wear of rubber plates is considerably less than white iron in the feed end half of the Mill and slightly more in the discharge end half of the Mill. Rubber components are lighter to handle but their installation is time consuming. This leads to the conclusion that a combination of ni-hard lifters a~~ rubber plates is the most economical compromise in Denison's case, for the Mill. Rubber discharge grates are superior to steel grates, while steel feed end liners are superior to rubber.The Use of Rubber Mill Liners at Denison Mines LimitedGrinding is done in two identic0al circuits each consist-ing of one 10 1/2 x 14' Dominion overflow rod mill, two Dorr Oliver quadraplex rake type classifiers, two 10 1/2 x 24' Dominion low discharge grate pebble mills and ancillary pumps and conveyors for pebbles. There is one centrally located distributor box that receives the discharge of the 4 pebble mills and splits it out to the classifiers."

Jan 1, 1974

By H. Utsunomiya

Most magnesium alloy sheets show low deformability in rolling. Edge cracks and transverse fractures are common difficulties. In addition, rolled sheets show well-developed basal texture <0001>//ND. The texture causes high anisotropy in mechanical properties and low formability in subsequent metal forming. Differential-speed rolling, where the upper and the lower rolls rotate at different speeds, introduces shear deformation through the thickness. Not rolling texture but shear texture evolves in the sheet so that the asymmetric rolling can be a method of texture control. However the primary slip system of the hcp alloy, is basal, the shear texture should be also basal. Differences between the two basal textures, i.e., the rolling texture and the shear texture, have not been understood completely. In this study, conventional (same-speed) rolling and differential-speed rolling have been applied to commercial AZ31B sheets at 623K. Microstructures, textures and mechanical properties of the rolled sheets before/after annealing are compared. It is found that the basal texture is more pronounced by the asymmetric rolling. On the other hand, the asymmetric rolling is effective to decrease the grain size and the planar anisotropy.

Jan 1, 2006

By Q. Han

Irradiation of high energy ultrasonic vibration in metals and alloys generates oscillating strain and stress fields in solids, and introduces nonlinear effects such as cavitation, acoustic streaming, and radiation pressure in molten materials. These nonlinear effects can be utilized to assist conventional material processing processes. This article describes recent research at Oak Ridge National Labs (ORNL) and Purdue University on using high intensity ultrasonic vibrations for degassing molten aluminum, processing particulate reinforced metal matrix composites, refining metals and alloys during solidification process, welding, and producing bulk nanostructures in solid metals and alloys.

Jan 1, 2014

By E. G. Joe

"The continuing increase in costs for power and fuel are affecting significantly the cost for milling of Canadian ores. In order to ascertain the scope and source of energy consumption in Canadian mills for further energy conservation opportunities, CANMET, in cooperation with the Canadian Mineral Processors carried out a detailed survey on the metallic mineral processing plants. Sixty-seven mills representing almost 300 million tons of annual capacity participated in the survey. The results indicated that in general, copper and iron ore mills, representing the bulk of the tonnage, consumed relatively low levels of energy per ton. Nickel-copper, zinc-copper and lead-zinc ore mills were moderate in energy consumption, while uranium and some copper-lead-zinc mills reported much higher energy consumptions due primarily to the increased heat requirements of the ore pulp. While the plant heating costs varied somewhat with the location in Canada, it was apparent that the lowest heating costs were achieved by those built with proper insulation and energy conservation design. If the cost per million British Thermal Units is taken as $2.00, the mill energy costs generally ranged from 40¢/ton up to $1.20/ton.IntroductionEnergy consumption in milling has always been of significant interest to Canadian mineral processors who traditionally calculate their milling costs down to pennies per ton. Even the measure of an ore's grindability is expressed empirically by Bond in kilowatts hours per ton milled. Some of the mills located in isolated areas were obliged to generate their own electrical energy from fossil or petroleum-based fuel at a cost substantially higher than that obtainable from captive or public hydro-electric installations. These mills practiced energy conservation long before the advent of O.P.E.C. energy cost inflation. One example of this was the use of electric boilers to produce process and heating steam during off-peak electrical load periods."

Jan 1, 1978

By A. G. Pentland

MODELS of mines may be classified under three headings: (a) sheet models, (b) solid models, and (c) skeleton models. Sheet Models are made of sheets of glass, celluloid, or a transparent plastic material. The sheets are mounted in a frame which holds them in a parallel position, either horizontally or vertically. Mine plans are traced on the horizontal sheets; sections on the vertical sheets. The model may be illuminated by electric lights which are separated from the sheets by an opalescent screen. It is viewed from above or from the side in such a way that the plans or sections are superimposed. Sheet models are very useful for the illustration of mines with narrow, steep-dipping veins, but they do not give a satisfactory representation of a large mine with a flat-dipping vein. Large sheets of glass are difficult to handle and to support in a frame.? It is difficult to see through a considerable number of them. Solid Models are made of plaster, concrete, wood, or other material usually in the form of slabs in which the mine workings are indicated by properly dimensioned cavities in the model. The slabs are coloured to show the veins, country rock, faults, etc. The model is divided along selected sections in order to give access to the interior by the temporary removal of parts. Solid models may be used to illustrate large orebodies of the Sullivan type, but they are cumbersome because parts must be removed to study details of structure. Skeleton Models are ones in which the underground cavities are represented by metal, wood, plaster, or wax proportionately shaped and held in place by a frame. They illustrate the work which has been done but do not show the position of the veins, dykes, faults, etc., in the unworked parts. It is necessary to project by eye between workings in order to determine the location of these features. The essential difference between the skeleton model and the solid model is that the skeleton model represents the mine workings by solid forms and does not show the unworked parts of the vein, whereas the solid model shows the vein as a solid and the mine workings as cavities in it. The skeleton model lends itself well to the representation of a large mine with large stopes.

Jan 1, 1944