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By Ursula M. Franklin

Old iron nails are one of the most common objects which entice the general public to ask questions about the history of metallurgy. There is a lot of history in old nails - history of the manufacturing industry, and social and economic history. Nails, therefore, are fine teaching tools; whether students have to acquire metallurgical skills or explore the structure and properties of wrought iron, whether they want to look into the history of inventions and the development of machinery, studying nails tells a story better than any teacher or any book. I have used this approach often and the following note is based on several student projects, particularly the work of Carmina Herrero and Vicky Marchant. Nails, those essential metallic fasteners, have long been with us. Their size, shape and design is basically a compromise between the makers' ability to control and manipulate material and the demands of the intended application. There were copper and bronze nails in antiquity, but in this paper I want to deal only with iron nails. In Rome, iron nails were common, and Cleere carried out the fine metallographic investigations on a large stock of nails recovered from a Roman fort site in Scotland. Those nails were hand forged; sorting them at the site on the basis of length, shape of head and shape of shank (in cross section) indicated that there seemed to have been some nail standardization. It appears that the Roman smiths used a series of heading dies starting with a 1/s-in. size. Each successive size increased by approximately 1/16-in. The metallographic inspection of the microstructures of the nails showed that the smaller nails were made in the one operation; i.e. both the tapering and the formation were accomplished on the heated rod without reheating. However, in the case of the larger nails, the nail had to be reheated for the tapering after the head had been forged. Most nails were tapered on all four sides of the shank and the shanks were square in cross section; only one group had rounded shanks. Most heads were flat disks, but in one group the heads were pyramids and another group had conic heads. Figure 1 shows the procedure used to produce the pyramidal heads. Obviously, Roman nail making was sophisticated and each nail design was meant for a particular use.

Jan 1, 1999

By Ben Burger

This paper describes the design, the first three years of operation and optimization of a large, single stage SAG mill at Minera Yanacocha?s Gold Mill facility located in northern Peru. The Gold Mill was commissioned in March 2008 with a 32? x 32? EGL, 16.5MW single stage SAG mill, to process 5 million tonnes per annum high grade oxide Au/Ag ore. Operational control, feed size distribution, grinding media, mill liner, grate and pulp lifter optimisation have allowed the mill to operate 15-30% above design throughput rates, but with a product P80 coarser than design. As part of the optimization, full grinding circuit surveys were conducted. Historical operating data and survey data were analyzed and used to evaluate possible circuit changes and determine alternative operating strategies. A number of changes were implemented which allowed the SAG mill to operate similarly to a large ball mill and achieve finer mill product that was closer to design. This paper summarizes life to date data analysis and improvements made by Minera Yanacocha as well as the grinding circuit optimisation study conducted by Metso Process Technology and Innovation.

Jan 1, 2012

By Sergio Cattalanl, Francis Chartrand

"The geology and origins of volcanogenic massive sulfide (VMS) deposits in the Abitibi belt of northwestern Quebec have been the subject of discussion since the discovery of the Horne orebodies in Noranda in 1923.The present Noranda version of the VMS model characterizes the ideal deposit as a stratabound, base-metal accumulation that is in close spatial relationship with hydrothermal alteration and stockwork zones, felsic lava domes, coarse phreatic-pyroclastic breccias, and subvolcanic intrusions that characterize vent- and proximal{acies submarine volcanic environments. Deposits tend to occur in a favorable stratigraphic interval within a mining camp, and this is well-documented in the Rouyn-Noranda and Matagami camps.However, in recent years many VMS deposits have been shown to deviate from the ideal Noranda-type. For example, the Ansi/ deposit is characterized by sulphide-bearing alteration zones that extend far above the massive sulfide lenses, and by abundant magnetite immediately underlying massive sulfide. The Horne deposit appears to lack the typical chloritic alteration pipe underlying the massive sulfide lenses, as well as laterally-equivalent exhalite horizons. The Horne and Quemont deposits, besides being the two giants of the camp, are particularly rich in gold, whereas others, such as WaiteAmulet and Millenbach, have low gold values. Finally, some deposits in the Noranda camp, such as the Ansil, Corbet and Mobrun mines, are outside the favorable stratigraphic interval. Therefore, it would appear that part of the key to renewing base metal reserves in northwestern Quebec is the use of evolving descriptive-genetic models that incorporate geological variations like those cited above."

Jan 1, 1990

By Robert M. Vadas

Special considerations are described as they apply to the design of ring gears for high-power grinding mills. AGMA requirements, the importance of the supporting structure, material selection and related field experience are discussed, with special emphasis on available and developing manufacturing technologies.

Jan 1, 1978

By R. W. Boyle

"The concept of using chemical methods in prospecting dates back at least to the middle of the 16th century. Modern methods of geochemical prospecting, however, based on secondary haloes and utilizing trace-element techniques, were first practised in the U.S.S.R. and the Scandinavian countries in the 1930's. After 1945, methods based on soils, stream sediments and vegetation were rapidly developed in the U.S.A., the United Kingdom, Canada, France and other countries.The modern methods of geochemical prospecting owe their rapid development in the 20th century to the following:1.-Recognition of the primary and secondary dispersion haloes and trains that are associated with all mineral deposits. 2.-Development of accurate and rapid analytical methods utilizing the spectrograph and the various specific sensitive colorimetrie reagents, especially dithizone. 3.-Development of polyethylene laboratory ware of all types and the development of resins. This permitted greater freedom of field analyses and reduced the incidence of contamination.4.-Development of gas chromatography. This permitted the rapid and accurate determination of hydrocarbons in petroleum prospecting.Future research in geochemical prospecting should be focused on the following tasks: 1.-Definition of geochemical provinces and their relation to mineral deposits. 2.-Development of methods for discovering large low-grade deposits. 3.-Development of methods for discovering deeply buried deposits. 4.-Further development of methods to outline primary haloes. 5.-Eiucidation and formulation of techniques to relate the size and intensity of anomalies to the grade of the deposits. 6.-Development and refinement of biogeochemical methods, especially those based on indicator plants, chlorotic or toxic effects, and microbiological techniques. 7.-Definition of the types of primary and secondary haloes associated with accumulations of oil and gas."

Jan 1, 1967

By Aidan Giblett, Michael McGlynn, Peter Radziszewski

"On the basis that 99% of the energy input into a mill is converted into heat, it is possible to estimate the amount of energy captured in the slurry, the amount that is lost to the environment as well as the possible means to reduce such losses. As a result it becomes possible to estimate the potential amount of energy that can be captured by technologies such as thermoelectric generators or even Sterling engines. Furthermore, it has been suggested that the energy recovery potential dry grinding circuit could be as high as twice that of wet grinding circuits.In this paper, the energy recovery potential of dry grinding will be explored by examining the case of the Newmont Carlin mine dry grinding circuit. The paper will open with a review of the energy recovery potential of a few wet grinding applications followed by a description of the dry grinding circuit and a definition of the control volume around that circuit. A thermodynamic model will be used to estimate the circuit discharge temperature and an estimate of any losses as well as provide an estimate of the potential impact of different means to reduce energy losses. The paper will close with a discussion of the assumptions used in model development."

Jan 1, 2016

"IntroductionThe Chairman, in his speech to this body last year in Montreal, stated that the Dominion Coal Board looked to and depended upon the Bureau of Statistics for statistical material, and the Bureau does collect and publish monthly and annual data on coal. It may therefore be asked why an officer of the Dominion Coal Board should prepare and give a talk on statistics.I would explain that it has been our experience in the Board that, since the supply and consumption of coal in Canada is subject to a seasonal ebb and flow, it can be more profitably studied on the basis of a twelve-month period ending on March 31st than of a calendar year, since the end of March does represent a fairly stable end point in this ebb and flow. The figures are not prepared or published by the Bureau on that basis and it has therefore been thought that a presentation on this fiscal-year period would be of interest. The Bureau of Statistics has agreed that this may be valuable and all the data here presented are based on the reports secured from various sources by the Mining, Metallurgical and Chemical Division, Dominion Bureau of Statistics. The only contribution by either myself or the staff of the Dominion Coal Board has been the tabulation in a different twelve month period, and the comments upon the picture presented.It should be noted that the data for the month of March, 1950, are not available in all cases and consequently the figures for that year contain an estimate for this month."

Jan 1, 1950

By w. w. Fraser

"In late 1985, Hudson Bay Mining and Smelting Co., Limited announced the Namew Mine/Mill project. Environmental baseline monitoring and planning began in early 1985 while a major drilling program was under way to delineate the ore deposit. This paper overviews the environmental assessment work conducted for the mine/mill operation, and outlines the tailings and water management practices.Planned environmental works and approach were affected in late 1988 when a massive water problem was encountered in the mine. The requirement to depressurize the rock surrounding the underground workings led to the need to develop, on short notice, an environmentally-acceptable procedure to dispose of a large volume of slightly-saline water.Biological toxicity tests performed on the depressurized effluent proved the effluent to be non-toxic and thus allowed resolution of the disposal problem. This resolution includes the conversion of a large water body from native fish species to a rainbow trout fishery."

Jan 1, 1991

By Gaston Gendreau

CETTE PRÉSENTATION traitera des différentes phases des opérations de la mine du Mont-Wright depuis ses débuts jusqu'à présent. A une brève description de la géologie du gisement, suivra un exposé des méthodes d'exploitation de la mine et du genre d'équipement utilize.

Jan 1, 1977

By Martin P. O'Connell

"IT IS INDEED A PRIVILEGE to address a group representing a sector of the Canadian economy so important as is the mining sector. Important, not only today, but certainly of great importance for the future development of Canada, for employment, for our trade balance and indeed, when one looks at what we are calling increasingly an industrial strategy, for the future. Surely mining will have a very significant role to play in fulfilling that. It's of special interest to me, as the Minister of Labour - and I ought to confess at the very beginning that I am just two months into this function - of special interest for me to know that you are giving such attention to labour-management relations. I think it is timely that, from my point of view at least, you do this, because for the first time in twenty four years major revisions of the Canada Labour Code as it relates to industrial relations and disputes settlements are currently in the House of Commons going through their second reading, after an easier introduction and some changes which I would be very pleased to describe later this morning. It is very timely too, I think, that we should be looking at this area because public interest is certainly at a high level. It is not only at a high level but it expresses a good deal of irritation with the current status and procedures and results in collective bargaining and there is some urgent search for more sophisticated or modified procedures for settling differences in labour-management relations. The public wants different kinds of results. I think that is apparent to all of us. They want results in terms of justice and equity on both sides. And it means that a Minister of Labour and certainly governments who often are representing, or are the third party in discussions, have a very important and complex role to play in attempting to create a balance as these two parties come to contracts and come to agreements."

Jan 1, 1972

By A. Roy MacLean

"Cape Breton is an island on the eastern extremity of Nova Scotia, Canada. Here, coal mining under the Atlantic Ocean has been a way of life since the early French militia mined coal for heating purposes in 1720. Despite many ups and downs over the intervening years, the coal industry has survived and is now in a favourable position to benefit from the upswing in international coal usage.Mining in Cape Breton Early mining in Cape Breton was done by hand picks and shovels. The coal was loaded into mine cars which were hauled by horses to the main haulage system for transport to surface. Later, compressed-air cutting machines and drills led to the use of explosives to blast the coal so that it could be loaded by hand and transported as above. In 1923, longwall mining (by hand) was introduced. In 1950, the Dominion Coal Company developed the Dosco continuous miner in order to mechanize the longwall coal-getting operation. At this time, conveyor belts came into wide-spread use, along with diesel locomotives to haul mine cars from the longwall face to the main transport system. During this period, coal was also mined by conventional mechanized room-and-pillar equipment such as cutting machines, loaders, roof bolters, etc. This system evolved into the use of the continuous ·miners of today, which are employed in the Lingan Mine room-and-pillar section. However, this method is only satisfactory at shallow depths and gradients. For these reasons, almost all the coal in this coal field will be mined by longwall methods. In 1968, the Government of Canada expropriated the assets of the Dominion Coal Company on Cape Breton Island in order to prevent complete closure of an uneconomic industry by its owners. The government created, by an Act of Parliament, the Cape Breton Development Corporation which now operates the coal mines, coal preparation plants, railway, shipping pier and ancillary services (Fig. 2). Since its inception, the Corporation has closed three mines, opened two new mines, is in the process of developing a third new mine, and has invested heavily in the one mine which remains from its previous owners."

Jan 1, 1985

By D. R. E. Whitmore, J. M. Harrison

There are five logical stages in the search for orebodies in virgin territory, namely: (1) reconnaissance inventory of geology, and related investigations; (2) development of broad concepts as a basis for selecting regions of potential mineral deposits; (3) assessment of criteria leading to specific localities within these regions; (4) geo-physical and geochemical studies that will delineate small anomalous areas; and (5) stripping, drilling or other means of locating ore. In addition, the development of new means of extracting mineral resources and the finding of new uses play a vital role in our mineral industry. The continued growth of this industry will be largely governed by our ability to develop or to adapt new concepts and techniques, and to produce a greater number of scientists and engineers. It should always be remembered that more than one-third of Canada's exports are dependent upon our ability to find, develop and economic-ally exploit new orebodies.

Jan 1, 1967

A newly developed damage model was used in the study of rock fragmentation mechanisms involved in crater blasting. Simulations show that at the detonation of the explosive charge, a crushed zone around the explosive charge is formed due to compressive failure and then a strong pressure wave is sent out forming a pressurized ring that propagates at the dilatation wave velocity. As the pressurized ring leaves the crushed zone, two tensile stress components perpendicular to the radial stress are developed in response to the action of the radial pressure, causing tensile failure and forming a damage zone around the charge. The formation of this damage zone is quite independent of the depth of the explosive charge provided there is no interference by the reflection from the free face. When the pressurized ring reaches the free face, it is reflected there and causes rock failure on the ground surface that forms another damage zone. Under the simulation conditions, it is revealed that the depth of charge is a factor controlling the relationship between the two damage zones. At a depth smaller than the optimum, the two damage zones coalesce into one and there is excessive rock breakage; otherwise, the two damage zones tend to isolate from each other with the increase in the depth of charge. Calculations of fragmentation indicate that the average fragment size increases and the uniformity of fragments decreases when the depth of charge increases as observed in practical blasting.

Jan 1, 1998

By B. S. Ignasiak, Dennis Carson

"Laboratory study of the behaviour• of binary coal blends shows that coke strength is more closely dependent on the distribution of ""reactive"" oxygen in the parent coals than on their proximate, elemental or petrographic compositions, and it also appears possible to qualitatively predict coke strength from information about reactive oxygen. Proceeding from this recognition, experiments were carried out to test the possibility of preparing metallurgical cokes from binary blends in which non-caking hvb coal was substantially freed of reactive oxygen by prior heat t1•eatment under controlled conditions. The results indicate that such blends can yield surprisingly strong cokes and that coke strength may be amenable to further improvements by modifying the size distribution of the pre-heated component and the rate at which it is charred."

Jan 1, 1976

By Brian L. Beninger

This paper discusses the application of the computer to coal preparation process predictions. In broad terms, the computer is used to perform two main functions. Firstly, the given float-sink analysis is interpolated and extrapolated to cover the entire actual range of raw coal specific gravity. Assumptions based on historical data must be made at times. Secondly, the partition curve, which, from historical data, defines the efficiency of a specific coal washing process, is applied to the washability data in order to determine the expected clean coal yield and quality. The vast amount of numerical work which is required to make a prediction of this type exhibits the need for computer methods in this area.

Jan 1, 1979

By K. A. Clark

"The repacked mineral aggregates of good grade oil sands have permeabilities ranging between 15 darcys to 350 millidarcys. The variation is due to the silt contents of the aggregates. Few good grade oil sands contain as much as 30 per cent •silt, most of them contain less than 20 per cent, and a large proportion have less than 10 per cent.The permeabilities of repacked good grade oil sands (oil included) depend on the degree of liquid saturation. When saturation with oil plus water reaches between 80-90 per cent, permeability is reduced to zero. As total saturation decreases below 80 per cent, permeability increases ranidly. Permeabilities of between one and two darcys were observed for total saturations between 60-70 per cent.The mean value for 18 measurements of the permeabilities of ""undisturbed"" core samples of good grade oil sands was 50 millidarcys. This value is •probably too high. The mean value for 20 measurements on core samples of interbedded oil sand and shale was 100 millidarcys. The mean value for 11 measurements on shale was 10 millidarcys."

Jan 1, 1960

By Matthew D. Meyer

SMART, an association of surface mining companies formed in 1995 to develop a coordinated approach to technology development for the mining industry, has recognized the need for the establishment of a worldwide database that continuously collects mining equipment data and provides metrics related to productivity and cost. Under the auspices of SMART, Syncrude Canada, Suncor Energy and Albian Sands Energy (three oil sands mining operations located in northern Alberta) have established a pilot project for mine benchmarking. This presentation will include a review of the pilot progress including: ???Data gathering techniques: means of collection and storage, proposed practice for data control and normalization, access to data/reports and format for data. ???Reports/analyses for individuals, across groups, within the total industry pool and publicly. ???Security and confidentiality of information belonging to identified parties. ???Sharing of best practices among members. SMART has identified two key deliverables to ensure success of the project. First, data supplied from surface mines must be validated and normalized to common definitions and then analyzed to provide participating companies with regular reports that allow them to understand their position and resultant opportunities to achieve world-class performance. This model maintains granularity of the data for each operation that can then be recombined into standard comparisons or specific indices as required. The general categories of: operating delays, maintenance downtime, standby, and scheduled downtime, have been used to frame comparisons. Second, participating companies are looking to go behind the indices to identify and share best practices that distinguish particular operations. The spirit of cooperation between the companies involved in the pilot project is meant to be a model for future expansion of the benchmarking project.

Apr 1, 2005

By D. J. Robertson

"THE copper smelting operation of the Hudson Bay Mining and Smelting Company, Limited, at Flin Flon, Manitoba, generates a gas flow of 350,000 c.f.m. at n.t.p. This gas stream passes to atmosphere through a 20-foot diameter by 250-foot brick stack, carrying with it an appreciable dust burden in the form of metallic oxide fumes. The flow constituents during the period 1952 and 1953 and •before gas filtration was included in the treatment scheme are shown in Table I. This paper describes the gas filtration treatment which was installed in 1957, using glass cloth media to recover this dust burden, and discusses the associated problem as its treatment for recovery of zinc and cadmium.The metallurgical details associated with the problem are illustrated by a description of the material flow sequence of the Company's hydrometallurgical zinc plant and copper smelter. In this ore processing complex, the zinc plant and copper smelter form an integrated unit within which intermediate zincrich products of each operation enter the treatment circuit of the other."

Jan 1, 1960

By F. Chiesa

The permanent mould process, which is a favoured process for producing premium quality aluminium casting, is rarely used to produce magnesium alloy parts. This may be attributed different factors such as: the reservation with which the automotive industry considers using magnesium in structural castings; also the relative hot shortness of most magnesium alloys when compared to aluminium A356/357 is another factor. A third reason stems from the fact that the "heat content" of magnesium is much less than that of aluminium, resulting in the difficulty, for a relatively slow process such as permanent mould (versus pressure die casting), to reach a mould dynamic equilibrium temperature sufficiently high to avoid premature freezing and misruns. The present work will address this problem by carrying out controlled cycling of a laboratory mould, poured with aluminium and magnesium alloys. The influence of insulation of the mould and artificial electric heating on the run-in mould temperature will be determined experimentally. A thermal model will be sought for these thermal devices that will allow to predict the thermal behaviour of moulds of different geometry before a single casting is poured. The model will be tested on an industrial casting in a workshop environment.

Jan 1, 2006

By F. A. McLean

At the Annual Western Meeting held at Blairmore, Alta., October 1924, the writer presented a paper drawing attention -to the advantages of portable gas-driven equipment for developing isolated mining properties. This type of equipment was at that time practically in its infancy and the details of results actually accomplished were somewhat meagre. During the last year or so a number of these plants have been installed so that it is now possible to offer more definite information regarding the actual mining progress accomplished with such plants and their cost of operation in various parts of the country. This paper has been written with the idea of reviewing the work done during the past year, and to supply data which may be of interest to those wh9 are confronted with the problem of selecting equipment for development or assessment work. Because drilling operations play such an important part in mining, one of the first problems that usually confront the prospective? mine owner is the selection of the proper com-pressed-air plant. The size and type of equipment and the method of driving it require careful consideration. The size and type of equipment is determined largely by the funds available, transportation facilities, and the speed with which the programme of development is to be carried out. The selection of the proper method of drive usually depends on local conditions, such as the relative cost of various fuels, and has an important bearing on operating costs.

Jan 1, 1926