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By A. D. Hunter, J. M. JR. Moore

"The Aldermac deposit and associated prospects occur in the Noranda Archean volcanic centre of the Abitibi greenstone belt. Over two million tons of are grading 1.65% copper, with minor gold and silver, were mined between 1933 and 1943. The deposit has features in common with the Vauze and Millenbach mines in the same district.Recent detailed mapping, geochemistry and petrography combined with data from former diamond drilling and mining operations permit a re-interpretation of the Aldermac area. The orebodies and spatially related sulphidic zones are con eluded to be volcanogenic.The host rocks are a chemically bimodal suite of mafic and rhyolitic flows, volcaniclastics and related subvolcanic intrusions. Massive sulphide lenses are spatially related to a quartz-feldspar- phyric rhyolite dome and siliceous, volcanic-exhalative sedimentary rocks, The succession is cut by gabbro and syenite, related to later stages of volcanism, and by post Kenoran diabase dykes. Regional metamorphism attained the low greenschist facies, but the rocks lack penetrative deformation.Hydrothermal alteration is primarily an intense silicification of mafic volcanic rock s enveloping, or lying below, sulphidic zones. Chlorite and sericite alteration zones, including dalmatianite, are more locally developed and have a closer spatial relation to mineralization, as do epidote, calcite and calcic garnet.The structure is complex and cannot be explained by isoclinals folding; rather it reflects concurrent faulting, and extrusive and intrusive activity. Fault blocks were rotated and exhibit opposed facing; the original selling was possibly a submarine graben.Sulphidic zones occur within mafic and felsic volcanic rocks and at the interface between the two; there is thus potential for discovery throughout the known stratigraphic succession. Exploration conducted according to a volcanogenic model is advisable, particularly in the light of recent discoveries in similar rocks of the Amulet area."

Jan 1, 1983

By R. Le Houillier, M. Nagamori, A. J. Plumpton

"Asbestos tailings are a typical serpentine, hydrated magnesium silicate, consisting primarily of antigorite and a few per cent of unrecovered fibrous chrysotile. Serpentine has unique thermal properties in that dehydroxylating calcination at 600 to 700°C can yield an amorphous structure in which most of the magnesia is liberated from the original bond with silica and thereby rendered chemically active. The amount of activated magnesia can be quantified by selective leaching with a weak acid such as acetic acid. Many wet processes have been proposed to extract magnesium values from calcined or natural serpentine by means of various acids and their ammonium salts. However, the only commercial utilization of serpentine today is found in dry processes such as the production of fused magnesium phosphate fertilizer .The present paper reviews the physical chemistry of the dehydroxylation of serpentine and also various wet and dry processes in order to provide a general view regarding the chemical transformation of asbestos tailings.IntroductionAsbestos fibers occur as chrysotile, a serpentine polymorph. More than nine tenths of mined asbestos ores consist of massive non-fibrous serpentine, primarily the polymorph antigorite, which is discarded as tailings after fiber extraction. For many decades, Quebec has been a world leader in the production of asbestos fibers. As a result, colossal tonnages of serpentine have accumulated in the Eastern Townships'!'. Serpentine minerals are found in large deposit s throughout the world, and significant research efforts have been made, particularly in Japan and the USSR, mostly in attempts to extract magnesia or silica values therefrom.The chemical composition of serpentine (chrysotile and antigorite) may be ideally expressed as Mg3Si2Os(OH). which corresponds to 43.7% MgO and 43.3% SiO2. Natural serpentines often contain a few per cent of Ni-bearing magnetite and other impurities, and therefore the contents of MgO and Si02are both about 40% or lower.Serpentine (hydrated magnesium silicate) is virtually insoluble in weak acids. However, when dehydroxylated under controlled conditions, ' it decomposes to an amorphous state in which magnesia and silica are isolated and chemically active. The magnesia so activated is readily soluble in weak acids. This unique characteristic of calcined serpentine, first discovered in 1942,, has since attracted the attention of innumerable researchers, whence many processes have been proposed."

Jan 1, 1980

By Claudia Gasparrini

"The ore microscope and electron microprobe, two common instruments for academic research, have not been used to full advantage in the Canadian mining industry, perhaps because they are not readily available to most mining companies.The present paper gives a description of the two instruments and of the manner in which, when used together, they contribute to the identification and description of mineralogical and metallurgical samples, and reviews the applications, to . date, in the mineral industry.The metallurgical applications can assist in determining the best separation technique for a particular metal or other economically important element, can provide explanations for poor recovery and/or liberation, can be used to determine theoptimum concentrate grade and can indicate environmental problems that may arise from the extraction process.In certain cases, the use of the two instruments may assist in the evaluation of new mineral deposits and in the determination of the origin of mineralization.IntroductionThe ore microscope and electron microprobe, two widely used instruments in universities and other research institutions, have not been exploited to their full potential by the Canadian mining industry.High-magnification, high-resolution ore microscopes, owned by most Canadian universities and government mining branches, are not widely used by mining organizations. The situation is very much the same with the microprobe. The geology departments of several major Canadian universities have easy access to this instrument. Fifteen of them, to the author's knowledge, own one and a few have already acquired or are planning on acquiring a second and later model. The mining branches of the Canadian Government have similar easy access to microprobes, as at least four of these instruments are available to them in Ottawa alone. The mining companies, on the other hand, except for the few larger ones which have their own research laboratories, have not been able to take advantage of electron microprobes in the past.This failure to exploit good ore microscopes and electron microprobes has been mainly due to a lack of expertise in the use of the two instruments for the study of metallurgical problems related to ore mineralogy. Government institutions providing research and test work to the industry are few in number, and are not always equipped with these instruments or are not geologically-oriented. Information provided on a consulting basis by universities and by government mining branches is normally limited, and frequently is not oriented to the needs of the mining company."

Jan 1, 1980

By D. S. Harries, R. I. L. Guthrie

"The use and development of scientific disciplines involved in heat transfer technology, related in general to steel masses and in particular to batch annealing, is demonstrated.The measurable benefits of cooperation are tabled; on industry's side, this includes a 10 to 20 per cent decrease in annealing time, and a corresponding higher productivity potential. The returned benefits to the academic engineer include the development and refinement of new computer algorithms related to heat transfer mechanisms.IntroductionThe object of this discussion is not really to describe an improvement in the batch annealing operation, but to use the project as an example of joint work between industry and the academic field. Both parties have derived a number of substantial benefits. These benefits will be listed, of course, but the batch anneal project will be used just as a typical example of cooperation. Why it happened will be explained, what actually happened will be described and finally some thoughts about areas in the field of heat transfer, where cooperation will continue in the future, will be highlighted. The paper will close with a message.Industry OverviewAt the outset, perhaps it should be understood that, in general, the Research Department at Dofasco believes that the universities and their staff are not destined for the problem-solving role in industry. Its opinion is that the university staff is best suited to the gathering and dissemination of knowledge. There are other more professional problem solvers for industry, including the steel industries' own individual investigation groups. Dofasco, therefore, looks to its academics for consultation. It benefits by bouncing ideas off them, and through rubbing shoulders with them in such a way that their knowledge can be tapped, and thus establish more effective scientific routes. In addition, the younger and brighter engineer s can broaden their scope through the intellectual contact with experts. The university professors can, it is believed, benefit through closer contacts with result-orientated research. They can also develop an appreciation of the fiscal control necessary for industrial investigations, without government subsidies, grants, etc., and with massive overheads."

Jan 1, 1982

By V. W. Shtenko, B. J. Ennis, P. H. Bridge

"The northeastern region of British Columbia contains large quantities of high-quality metallurgical coal. To market the coal, it was necessary to provide the required infrastructure which included rail access. This paper presents the role of the British Columbia Railway in the northeast coal development.In 1976, B.C. Railway undertook to study two main routes, one originating at Chetwynd and the other at Anzac, both located on the main line, north of Prince George. The routes studied are briefly described, detailing the methodology and engineering analysis carried out to permit the selection of a single route that would be the most cost effective, taking into consideration the construction, maintenance and operating costs. The operating parameters, track and grade standards, anticipated tonnage, construction costs and the final route selected are also presented.Pre-engineering analysis and studies of the route selected originating at Anzac, known as Tumbler Ridge Branch Line, and which commenced in 1977, were concluded in 1978. New mapping was developed to a scale of 1:2000 with good vertical and horizontal control. Based on the mapping data, terrain analysis, and designs developed, an estimate of construction costs and schedule of work was developed.Authority to proceed with the final design and construction was provided in December 1980, with the first shipment scheduled for December I, 1983. Final designs of all structures are discussed, including schedules, cost to completion, and control systems utilized. The decision to electrify the Tumbler Ridge Branch Line and related topics are discussed, with a brief description of train operations. The present status of the project is also presented."

Jan 1, 1983

By L. Yacher

Most metallurgical plants already have sophisticated control systems as well as a process-historian that manage thousands of real-time and historical variables. There exists a huge potential for operational improvement through the inference of patterns, correlations and cause-effect relationships within these records. The ability to run online and offline advanced multivariate statistical analyses represents a great potential for the mining industry, in various areas such as cathode quality improvement in an SX/EX plant, the analysis of the correlation between the ore characteristics and the mill throughput, the determination of early failure alerts for major equipment, etc. The background theory is described, as well as some practical experiences of operations in Chile and Peru. Cu2007

Jan 1, 2007

In order to avoid impurity problem and enhance absorption/desorption kinetics of Mg-based compounds, nanostructured Mg-based compounds were synthesized from Mg, Ni and other elemental nanoparticles produced by hydrogen plasma-metal reaction. XRD and TEM results demonstrate that homogeneous nanostructured Mg-based compounds with less impurity were successfully synthesized by this method. DSC in hydrogen atmosphere, pressure-composition isotherm and the kinetics of hydrogen adsorption/desorption were investigated at different temperatures. The results show that the nanostructured Mg-based compounds can absorb hydrogen in a high speed at a low temperature.

Jan 1, 2005

By Steve Scott

Green Economy Toyota Prius Hybrid contains about 50 kg of copper. All-electric cars have about 100 kg of copper. From where will all the copper come? Wind turbines have 1 metric ton of copper China is building 221 cities of 1 million people by 2025 (13 cities per year from 2008) = 10 New Yorks. The Greater Toronto Area has 5.6 million people, so a new GTA every 22 weeks!

May 1, 2013

By William D. Gallant, Thomas M. Barczak, Carol Tasillo

"This paper describes the results of full-scale testing of several multi-layered wood crib configurations that were tested in the Bureau of Mines mine roof simulator in cooperation with the Cape Breton Coal Research Laboratory and Cape Breton Development Corporation of Sydney, Nova Scotia. Nine different crib configurations currently being used as wood packwall supports for advancing longwall applications in Canada were evaluated. Configuration parameters understudy included the aspect ratio (height-to-width relationship) and percentage of solid material used in the crib construction. Test results and generalized wood crib behaviour are discussed in detail. Recommendations are made concerning crib constructions to maximize strength and stability. A cost benefit analysis of multi-layered wood crib configurations is made. A comparison of laboratory results and underground observations of several wood packwall supports in the Sydney coalfield suggest in situ load capacity is less than that measured in laboratory testing. Reasons for the apparent decrease of in situ load bearing capability are described.IntroductionA cooperative effort was undertaken by the U.S. Bureau of Mines with the Cape Breton Development Corporation (CBDC) and the Cape Breton Coal Research Laboratory (CBCRL) to evaluate the behaviour of gateside packing materials used in advancing longwall mining applications in the Sydney coalfield. As part of this effort, full-scale tests were conducted on wood packwall supports in the Bureau's 3-million pound (13.3 MN) active load frame.Nine different pack configurations were evaluated as part of this study. The wood packwall supports were multi-layered crib constructions from 6 in. (0.15 m) by 6 in. (0.15 m) cross section timbers using timber s 30 in. (0.75 m) and 60 in. (1.5 m) in length . The percentage of solid material in the crib constructions varied as illustrated in Figures 1 and 2. A summary of crib constructions is provided in Table 1."

Jan 1, 1991

By W. J. Farley

"The Sherritt Gordon mine is 100 miles north of The Pas in northern Manitoba. Copper-zinc ore was discovered on the property in 1922. Production began in 1931 and continued to June, 1932, when operations were suspended because of the low price of copper. Operations were resumed on August 1st, 1937, and have been carried on continuously from that time to the present (March 1947). The production of metals up to the end of 1945 was copper, 287,129,880 lb.; zinc concentrate (50 per cent) 104,419 tons ; gold, 79,388 oz.; silver, 2,529,974 oz.GENERALThe ore occurs in two deposits, the east and the west. Both are enclosed in gneisses that are highly metamorphosed sedimentary and volcanic derivatives. The rock beneath the deposits, and hence forming their footwall, is gneissoid quartzite; the hanging-wall rock is basic garnetiferous hornblende gneiss. Pegmatite commonly occurs along both foot- and hangingwall peripheries and as isolated blocks and fragments within the ore zone . These blocks and fragments are considered to be residuals of unreplaced host rock .The ore is relatively coarse grained and ranges from the massive to the disseminated type. The metallic sulphides composing these, named in the order of their abundance, are pyrite and pyrrhotite ( 2-1 ratio) , chalcopyrite, sphalerite (marmatite) , and minor chalmeriite; subordinate amounts of gold and silver are recovered . The insoluble content of the ore averages about 35 per cent.Another deposit known as the Bob Lake, much smaller and lower in grade but having very similar relationships, occurs about 3 ½ miles to the northeast of the main Sherritt Gordon ore masses.STRUCTUREThe Sherritt Gordon orebodies are of the replacement type, and lie within a pegmatite sill that has been intruded along a contact between quartzite and hornblende gneiss. The two main orebodies are intimately related, for the east deposit is an erosional remnant of the lower, easterly limit of an orebody once continuous with the west body. The ore lies along the southwest limb of an overturned syncline."

Jan 1, 1954

By J. C. Ingles

"A new technique is in the process of revolutionizing inorganic chemical analysis. Galled atomic absorption spectrophotometry, it combines the use of a special light source, a flame, and the equipment of conventional spectrophotometry, to provide a quick, reasonably accurate method for the determination of a large number of elements.This paper outlines the principles on which it is based, describes the commercial instrumentation"" available for exploiting it, and. summarizes current applications in process metallurgy."

Jan 1, 1966

By Matthew S. Hall

Gold/iron oxide catalysts have been prepared and their catalytic performance evaluated for low temperature CO oxidation. The method and temperature used to dry the sample has a significant effect on their catalytic activity. Analysis by TEM revealed the catalysts contained Au particles, although catalysts with high and low activity did not always differ in their microstructure as evidenced by TEM. Catalysts were characterised using XPS and the difference between the Au(4d) and C(1s) binding energies measured; in general the greater the difference, the higher the catalytic activity of the material.

Oct 1, 2003

By F. L. Casey

"Part 1 – Published Papers Baria, G., and Boshkov, S., ""Insights into Undercuttingin Block Caving"", Proc. 5th Rock Mech. Symp.,Mines Br. - Information Canada, 41-58, 1970.Barron, K., Coates, D. F., and Gyenge, M., ""ArtificialSupport of Rock Slopes'', Mines Branch ResearchReport R228, July, 1970.Barron, K., ""Criteria for Brittle Fracture Initiation inand Ultimate Failure of Rocks and Their Applicationto Fracture Zone Prediction"", Proc. 2ndCongr. Int. Soc. Rock Mech., Belgrade, 1970, 3-37.Bauer, A., and Calder, P. N., ""Projectile Penetration inRock"", Proc. 5th Rocle Mech. Symp., Mines Br. -Information Canada, 157-170, 1970.Bauer, A. M., ""Site Development and Rehabilitation ofPits and Quarries"", Canadian Mining Journal,Vol. 91, No. 7, 77, July, 1970."

Jan 1, 1971

By E. A. Rychkun

"For the last 700years of recorded economic history, man has been subjected to alternating inflationary and deflationary patterns. Through this period of time, a severe deflationary pattern has developed approximately every 55 years, creating 12recordable occurrences. Through the last two centuries, this severe deflationary phenomenon has come to be known as a depression. As these depressions have repeated themselves regularly, they are cyclic. This in turn leads to the question of whether the 13th cycle will also repeat itself in the form of a depression. As this cycle is now 51 years old, we must consider the possibility at about 1984.In analyzing a 700-year record of consumer prices in Southern England, the 55-year cycle appears to vary in shape and intensity. This varying phenomenon is due to the effect of longer cycles upon which each one ""rides "". Because each cycle effectively rides on the next largest, which in turn rides on the next largest and so on, the combined measured effect of all cycles together at any point in time is always unique. This means that anyone cycle can never repeat itself in an exact identical manner. The combined effect therefore is what we observe in the form of prices and, as cycles interact, variations in deflation are produced . The ""science"" of economics attempts to quantify and develop theory on situations which are never identical and hence can be conservatively classified as a useless predictive tool.This means that more unconventional approaches may be required to predict our economic future. In looking at previous depression cycles, it is possible to recognize similarities in human behaviour patterns and hence the resulting economic movements. These behaviour patterns create major events or influencing factors which set the scene for a major deflationary condition. The way in which these factors occur, however, is not predictable. As more and more of these similar events are identified in each cycle, we can increase our confidence on the probability of the last event occurring (a depression). By also unravelling the set of larger cycles, we can determine the potential combined effect at any point in the future.This paper presents a system of cycles ranging from 800 years to 3 years which appear to operate in our economic system. By so doing, a long-term projection into the next century can be made. Finally, the paper deals with the main controlling similarities within the depression cycle, to show that a comparison with our current cycle implies that a major deflationary collapse in the mid 1980's is virtualy inevitable."

Jan 1, 1980

By D. Seo, P. Au, X. Husang, D. Nagy

The production of single crystal (SX) turbine blades represents the current stateof- the-art in Ni-based superalloy design. With complex casting processes and alloy composition modifications, SX superalloys exhibit superior high temperature mechanical properties to their polycrystalline counterparts. Stresses and plastic deformation can occur in SX nickel-base superalloy engine components at various stages during their manufacture and use. For examples, stresses are created during initial solidification and also during solid state processing such as shot peening, grit blasting, blending, electrodischarge machining and welding. Stresses may also be created during service due to random events such as foreign object impacts. Subsequent exposure of SX to high temperatures during solution heat treatment and brazing repair can result in recrystallization which has been shown to be detrimental to both creep rupture strength and fatigue performance of the components. It is therefore the objective of this paper to understand the recrystallization behavior of two SX superalloys, PWA 1484 and 1483, subjected to pre-stressing and subsequent heat treatments.

Jan 1, 2006

By R. D. Brown

In the spring of 1977, Revenue Canada announced its intention to proceed in 1978 with a plan to impute a taxable benefit on interest-free and low-interest loans provided to employees. Such loan arrangements are often an important aspect of the compensation packages provided by many companies to their employees. Since the original announcement, there have been many submissions to Revenue Canada opposing this change, and the Finance Minister has now brought down a compromise solution with the introduction of a proposed amendment to the Income Tax Act. The amendment, which would not take effect until the 1979 taxation year, would require an employee, a shareholder or a related person to include a benefit in income measured as the difference between the interest on any such loan computed at bank prime rate and any interest actually paid. Only the amount of such a benefit in excess of $500 in a particular year would be required to be included in income. Of particular interest is the exclusion from these benefit rules of loans up to $50,000 in respect of the purchase of a house on the relocation of an employee and loans provided for the purchase of shares of an employer corporation.

Jan 1, 1978

By J. A. Finch

"This paper describes major technical developments in rod mill design and operating practice since its introduction into the North American minerals industry over fifty years ago. The basic operating characteristics of the wet, overflow rod mill are described, and significant operating variables are reviewed in terms of their effects on mill power draw, power efficiency, and practical aspects of circuit operation. Key factors for improving the economic performance of rod milling circuits are identified. IntroductionThis paper summarizes the findings of a detailed review of available technical information on the operation of rod mills. One of the basic problems in historical comminution testwork has been the lack of a standard measure of circuit performance. The Bond Operating Work Index, not introduced until after 1950, has proven of immeasurable value in this regard, but first has to be carefully considered in terms of its utility and limitations. Its prescribed use is described in a later section of this paper.During this review, it became apparent that rod mill performance is generally not well understood. Because of combined interactions, the effects of different operating variables may be difficult to assess, and even at times appear erratic. It is obviously difficult to rationalize plant testwork or circuit adjustments when the results are highly unpredictable. The purposes of this review, therefore, were:a) to establish what basic facts have been learned about rod mill performance;b) to define some genera l guidelines for efficient rod mill design and operation; and,c) to establish a basis for specific recommendations for plant tests or adjustments with minimum risk, and maximum potential for circuit performance improvement."

Jan 1, 1986

By John H. Fowler

Nova Scotia has been mining and exporting industrial minerals for over two hundred years. As an industrial mineral producer, this province continues to rank as the number one gypsum mining and exporting region in North America. Mining of many other commodities is ongoing, supplying many local and export markets. In all, excluding aggregate producers, there are nineteen industrial mineral producers operating at thirty sites producing nine commodities including anhydrite, barite, clay and shale, dolomite, gypsum, limestone, salt, silica sand and stone (Fig. I). Numerous aggregate producing operations supply all the province's aggregate requirements and export some of these materials to other regions of Atlantic Canada and as far away as Bermuda (Fig. 2) . Production value of industrial mineral commodities in Nova Scotia for 1982 was $105 million , representing 39% of the total value for all mineral production for the year. Because of the general improvement in the economy, indications are that the 1983 value of production will be higher.

Jan 1, 1984

By E. Mohammadi Zahrani

In this study, Mg-doped fluorapatite (Mg-FA) nanopowders were prepared through a sol-gel, technique and characterized. Designated degree of Mg2+ ions incorporation into the apatite structure was indicated by the x value in the general formula of (Ca10-xMgx (PO4)6F2), where x=0, 0.25, 0.5, 0.75, and 1. XRD, AAS, FTIR and TEM techniques were utilized to characterize the synthesized nanopowders. In vitro bioactivity of the powders was evaluated in simulated body fluid. Powders had a crystallite size less than 100 nm. It was concluded that Mg-substitution could alter bioactivity and dissolution behaviour of Mg-FA. These two parameters were proportional to magnesium content of the powders.

Jan 1, 2010

By Yu-Min Cheng

Over the past two years, the construction industry has increasingly recognized the benefits and capabilities of building information modeling (BIM) for information integration, visualization and parametric design, reducing the duplication of work and complexity of interface integration, while significantly saving both time and cost. However, due to the variety of participants in engineering projects, the differences between data definition, data format, and data storage increase the difficulty of integrating data from diverse sources. Therefore, buildingSMART has developed a common data schema, called Industry Foundation Classes (IFC), that makes it possible to hold and exchange relevant data between different software applications, to increase the efficiency of BIM work and to ensure a consistent and high-quality output. This paper presents a novel methodology that assists in facilitating the import and export process for parametric BIM objects between heterogeneous BIM systems. This methodology is based on the IFC data schema and includes graphical and non-graphical description data. The objective is to retain the geometry, parameters, unit, texture and links of an object during exchange and sharing to ensure that data integrity is maintained. To sum up, this research addresses the issues of transferring parametric BIM objects between heterogeneous systems to increase data integrity and reduce transfer and integration times.

Aug 1, 2013