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By A. A. Levinson, M. B. Kirkley, J. J. Gurney

"Scientific advances in the past decade have greatly clarified our understanding of certain concepts relating to the age and origin of diamonds. These advances are largely the result of geochemical studies of mineral inclusions in diamonds, made possible by modem analytical techniques which enable the accurate chemical analysis of micro-sized particles of the order of 200 microns in maximum dimension. As a generalization, the inclusions indicate that most diamonds formed from either of two rock types, peridotite and eclogite. Peridotitic diamonds have yielded ages of 3300 million years, whereas eclogitic diamonds areyounger and rangein agefrom approximately 1000to 1600million years. Kimberlite and lamproite, the two rock types usually associated with diamonds, typically are much younger than the diamonds they contain. Thus, it is now dear that kimberlites and lamproites are only the transporting mechanisms which brought diamonds to the surface and are in no way related to the formation of most diamonds. The latest concepts which developed during the past decade regarding the sources of carbon for the crystallization of diamonds from peridotite and eclogite, and the mechanisms of kimberlite and lamproite emplacement, IntroductionThe decade of the 1980s has seen major advances in our understanding of the age, origin and emplacement of diamonds. The information presented herein is applicable to virtually all natural diamonds, excluding diamonds related to meteorite impacts. There is still some question, however, as to the applicability of the new information to industrial grade ""fibrous"" or ""coated"" diamonds, and to microdiamonds (< 1 mm). In addition to drawing upon our own experiences, this review is summarized from a voluminous literature and for those interested in the original sources we recommend the books by Mitchell and Bergman (1991), Ross (1989), Nixon (1987), Mitchell (1986), Glover and Harris (1984) and Dawson (1980), and the review articles by Mitchell (1991), Gurney (1989) and Meyer (1985).are also discussed."

Jan 1, 1992

By Robert B. Parsons

"Ontario and Quebec taxpayers will have to dig deeper into their pockets to pay more tax, according to budget papers tabled in these provinces in May 1993. Individuals will be hardest hit, but corporations will also have to ante up in the face of higher rates, reduced deductions, and new taxes.Up, up, and away...Somewhere in the bleak picture of the 1993 Quebec and Ontario budgets, there is a bit of good news for the mining industry.Careful scrutiny reveals:• Ontario will correct a capital tax provision which inadvertently penalizes flow through share issuers;• Quebec&apos;s flow-through incentives will be extended to December 31, 1995; and • both Quebec and Ontario will allow deductions for mine site reclamation payments.The industry may also find some comfort in the fact that Ontario&apos;s new corporate minimum tax will be profit-based (unlike the federal minimum tax), so that non-producers should not face a liability for this tax. There is some concern though, about Quebec&apos;s announcement that the refundable credit mechanism in the Mining Duties Act will be reviewed."

Jan 1, 1993

By Jacques Ouellet

Outline What is Microwave energy Investigation of transparency of 40 minerals Melting of Andesite in a MW oven Numerical modeling /Computer Simulations o FEM analysis ?? Some laboratory experiments o Particle Modelling Mw Application to Rock Breakage o A MW Rock Drill Prototype Conclusions What is Microwave energy Microwave energy is an electromagnetic wave consisting two electronic & magnetic wave traveling perpendicular to each other and transporting energy with the speed of light.

May 1, 2008

By R. H. McCorkell

Measurements of radon in air and aqueous solutions can be affected by leakage from vessels in which samples and standards are kept and by absorption and later release of radon by the materials of these vessels. The author had received various oral communications concerning the se processes : e.g ., that natural rubber and greases absorb large amounts of radon, whereas silicone rubber and grease do not; and that radon is readily lost from polyethylene bottles and that inverting glass bottles containing aqueous samples reduced radon loss from them . However, the results of actual tests and quantitative data showing these effects were not available. For this reason, it was necessary to make numerous measurements of the leakage and absorption of radon in the course of designing apparatus and methods for measuring radium and radon concentrations. It was thought that the data obtained might be of use to others, and consequently they are compiled in the present note .

Jan 1, 1980

By Janet E. Halliwell

In keeping with the traditions of the Science Council of Canada - an independent and forward looking agency that applies broad and multidisciplinary analyses to the various issues it examines the author indulges in a holistic approach to the integration of the environmental, scientific, economic, and cultural concerns. This paper will characterize the changing conditions which the mining industry is facing. It will then explore the changing expectations of society with respect to environmental sustainability and how those attitudes in turn, must influence the strategic directions and attitudes of the industry, and within that, the role of science and technology.

Jan 1, 1991

Mining Impact in Water Quality: Understanding the conflict Mining is an industrial process Metal mines that chemically process ore to concentrate metals such as copper and gold use more water than non-metal mines such as coal, salt and gravel. Tailing Ponds Water contaminated with high concentrations of metals, sulphide minerals, dissolved solids, or salts can negatively affect surface water quality, aquatic ecosystems and groundwater quality.

May 1, 2013

By Alan G. Galley

"Advances in our knowledge of the petrochemical attributes of deposit environments and of the character and extent of hydrothermal systems associated with certain deposit types has resulted in increased application of lithogeochemistry to exploration programs. Lithogeochemistry can be used to vector an exploration program toward an area of high potential through the use of a series of collapsing scales of analysis from a tectonic subprovince down to a particular stratigraphic segment. In the case of volcanogenic massive sulphide (VMS) deposits this involves the recognition ofsuitable volcanic domains, and the identification of subvolcanic intrusions and cogenetic felsic extrusive complexes. The recognition of chemical vectors within regional-scale alteration zones and associated chemical sedimentary rocks allows the geologist to identify the stratigraphic units with the most potential for hosting a base metal deposit.An integrated lithogeochemical program requires the judicious use of major, trace and rare-earth element and isotopic analysis. Standard discriminant plots may be employed to identify suitable tectonic and lithologic environments. Analysis of the chemical and mineralogical variations in broad-scale, semi-comfortable alteration zones provides a useful set of vectors to VMS mineralization. These may include contouring raw data, element ratios on XY plots, normalizing data against known rock values, or calculating mass changes in alteration zones."

Jan 1, 1995

By Robert B. Parsons

"Canadian income tax legislation contains a number of provisions which serve to facilitate the structuring of business arrangements, including mineral resource ventures. These rules are often fairly complex and not easily understood. This article attempts to explain in plain and understandable language the mechanics and benefits of one of the more frequently encountered provisions, the ""Section 85 election"".IntroductionThe Canadian resource industries are probably singled out for more special attention under this country&apos;s tax legislation than any other industry. This special treatment is, of course, not always welcomed by the industry, such as where unnecessarily restrictive taxation is perceived to exist or where agonizingly complex tax legislation must be dealt with. On the other hand, certain provisions in the tax legislation treat the industry in a relatively favourable manner, including a number of rules which, in recognition of the high risk and capital requirements of the resource sector, serve to facilitate the structuring of resource ventures."

Jan 1, 1984

"Nanisivik Mines Ltd. operates a 10-M W diesel-electric generating plant at its zinc-lead operation on Baffin Island in the Canadian Arctic. This paper provides a description of the plant and the integrated waste heat recovery system. Data is presented detailing the actual costs of operating a plant over a period of seven years. Problems in operation are described as well as the success of the plant in meeting its objectives over the years. IntroductionNanisivik is located on the shore of Strathcona Sound at the north end of Baffin Island (Fig. I). Nanisivik Mines Ltd. has operated a 2,100 tonne per day zinc-lead underground mine and a concentrator, together with supporting infrastructure, at this location since October 1976. Annual production of 100 000 tonnes of zinc and 10 000 tonnes of lead concentrate is transported by ship to Europe during the mid -July to mid October shipping season.All electrical needs of the project are provided by the company-owned and -operated power plant. Facilities served by this electrical system are the underground mining areas, the concentrator and industrial area, a townsite, airport, and shiploading dock complex."

Jan 1, 1986

By A. I. A. Salama, M. W. Mikhail

"The existing methods of block diagram manipulation and vanishing variable for flowsheet simplification used in coal and mineral processing circuit evaluation and optimization cannot be easily implemented on digital computer.The signal flowgraph technique is proposed to represent and simplify determination of the relationship between intermediate or end variable and the feed in the flowsheet. Typical and existing circuits are used to demonstrate the application of the proposed technique which can easily be implemented on digital computers.IntroductionRecently there has been much interest in the analysis and optimization of coal and mineral processing circuits to assist in the pre diction of coal and mineral processing plant performance. The block diagram and the vanishing variable were introduced and utilized in the analysis of plant flowsheet. Although the block diagram approach is useful, it requires manual manipulation of the circuit block diagram which may present difficulties in the situation of complex circuits. Moreover, it may not be easy to implement on a digital computer.In this paper, the signal flowgraph technique is proposed to represent the circuit flowsheet and to simplify the determination of relationships between intermediate or end variables (fractional mass) and the feed for any coal and for any mineral processing circuit comprising size and density separators. These relationships are utilized in the analysis and/or optimization of the circuit. The proposed technique is illustrated by considering typical and existing circuits."

Jan 1, 1987

By R. G. Bradbury

The paper uses two hypothetical, but typical, situations to show that hydraulic rock drilling equipment has very significant economic advantages over pneumatic equipment both in drifting applications (even in the situation where advantage is not taken of the high productive capacity of the hydraulic drill) and production drilling applications. Other factors, including the non-economic advantages and the disadvantages of hydraulic drilling, are discussed. The paper concludes with a brief analysis of why the Canadian mining industry has been slow to take advantage of this apparent broadly advantageous advance in rock drilling technology.

Jan 1, 1979

By D. Djokic

One of the most attractive features of electron beam curing as a process for manufacturing composite structures is the potential for attaining very low levels of residual stress as compared to thermal curing. This residual stress reduction is important both for the potential to reduce composite failure strains at low operating temperatures and the associated reduction in process-induced deformation. Previous work has demonstrated that it is possible in some cases to significantly reduce residual stress development during irradiation and also avoid development of additional residual stress during post cure. In this paper, simple L-shaped composite laminates were used to study the development of residual stress and deformation during thermal post-cure of specimens that were already partially cured using different radiation doses. Following post-cure, these specimens were also subjected to high-temperature loads to study creep behaviour under service conditions. Aerospace

Jan 1, 2006

By R. E. Molnar, P. A. Riveros, V. M. McNamara

"This paper describes some recent research done at CANMET in the areas of ion exchange and A VR (Acidification- Volatilization Reneutralization), as applied to the recovery of gold and cyanide, respectively. It also discusses the ways in which these two technologies may be combined in order to minimize the environmental impact of gold milling operations and optimize reagent usage. IntroductionGold milling operations can essentially be divided into those that carry out a liquid/solid separation after leaching and those that recover gold directly from a leach pulp. The former produce a barren solution which may contain considerable amounts of cyanide, either free or cornplexed with metals. The latter produce a similar solution but this is now part of a slurry rather than a clear stream. Due to its toxicity, any excess cyanide must be destroyed before the effluent is discharged into the environment. Ideally, this should be (and sometimes is) accomplished by natural degradation. However, in many cases natural degradation alone cannot remove the last traces of rnetallocyanide compounds from the effluent and , as a result, most Canadian gold producers utilize a supplementary chemical oxidation system. This not only increases the operating costs, but concerns have also arisen in recent years about the formation of ammonia as a result of the chemical oxidation of cyanide (via CN--CNO--HCNO-NH3) ·"

Jan 1, 1993

By C. S. Lord

"The Regal Silver mine is 5 miles north-northwest of Albert canyon; a station on the main line of the Canadian Pacific railway; 21 miles east of Revelstoke; British Columbia.Development, commenced in 1918, comprises more than 8,000 feet of workings from six adits, one of which extends into the Regal Silver property from the adjacent Snowflake ground. Production has been limited to a little tungsten concentrate recovered recently from a few r..undred tons of ore treated in a small underground mill. The property has received some attention as a possible source of tin. The deposits are large quartz veins containing irregular sulphide bodies. Ore minerals normally make up less than 1 per cent of the veins and include pyrite, galena, sphalerite, scheelite, and stannite. The veins are approximately parallel with the bedding of the enclosing graphitic, siliceous to calcareous, slates and argillites. These strata are of Precambrian age, strike about northwest, and dip northeast. No other rocks are known in the vicinity of the workings . Granitic rocks, intrusive into t'he sediments, outcrop 4 miles to the southwest and 7 miles to the northeast and may underlie the property at no great depth."

Jan 1, 1954

By D. A. Peterson, R. Pakalnis, G. Peter Mah

"Laboratory and trial installations have been completed to determine the potential of composite cable bolt reinforcement in Canadian underground mines. Several prototypes of glass fibre cable bolts have been developed and tested, two of which are currently available to the mining industry. Their evalualtion consisted of lab testing in Canada and the United States, along with trial installations in several underground mines throughout Canada. The objective was to develop a cost competitive composite cable bolt equivalent in strength to that of a 16 mm (Ys in.) diameter steel cable bolt. In addition to achieving equal or superior load carrying characteristics in tension, the glass fibre cables generally experienced an increase in the rate of installation due to their lighter weight. Unlike conventional steel cables, composite cables may be installed within mines which utilize continuous excavation and which require cuttable support. A market analysis of cable bolt usage in Canada has been completed. Glass fibre cable bolts are an effective means of rock reinforcement in mining applications. They prove to be a viable alternative to conventional steel cable bolting. IntroductionCurrent cable bolting practice consists of cement grouting one or more steel cables within a drill hole in order to support the surrounding rock mass. Cable bolts are a form of internal support and are generally used as pre-support in open stope and cut-and fill mining methods. They can be either tensioned (active support) or untensioned (passive support) and may be of any length, though for underground mining applications, are generally less than 20 m (65.6 ft) and are untensioned. A major advantage of cable bolts is that they are flexible and can be coiled to approximately 1 m (3.3 ft) diameter coils. This allows relatively long lengths (>20 m, [65.6 ft]) to be installed in areas with limited head room (1.8 m)."

Jan 1, 1994

By C. Dodds, R. S. Ferrari-John, The University of Nottingham, G. Dimitrakis, J. Katrib, A. R. Batchelor

"Sorting technologies have the potential to reduce energy use in comminution by rejecting uneconomic ore before feed material enters the mill. However, a major challenge for sorting porphyry copper ores is providing a basis of discrimination between valuable and non-valuable fragments, due to their complex mineralogies and textural features. Microwave heating in combination with infra-red detection (MW-IR) has been shown to provide upgraded feedstock for certain ores at bench scale. Selective heating of copper sulphide minerals compared to the gangue leads to an increased thermal response for valuable fragments, providing the basis for sorting.Rapid scale up of MW-IR from bench scale to a 100 t/h continuous pilot plant facility has been facilitated by the design of microwave choking structures to allow continuous operation at industrially meaningful throughputs, whilst meeting health and safety and electromagnetic compliance standards, and the integration of materials handling with electromagnetic systems.Laboratory batch testing on a pilot scale microwave system has been undertaken to investigate the thermal response of copper ores under industrial conditions, at microwave energy inputs up to 1 kWh/t. These results provided the operating window and recommended test conditions for the continuous pilot plant. Sortability curves predicted in the laboratory are in good agreement with separations achieved during continuous pilot plant operations. The potential microwave sortability of a number of ores has been studied, allowing informed decisions to be made about potential ore candidates based on mineralogy. Future development of the technology will be underpinned by the creation and validation of scale up concepts for 1000 t/h operations. Understanding the value proposition for individual sites/applications will be central to unlocking the potential economic and environmental benefits of microwave sorting."

Jan 1, 2016

By A. R. Trusiak, C. Bazin, D. Hodouin

"The On-Stream Analyzer has proven, and is still proving to be, an extremely valuable tool for the control of flotation circuits. This paper examines the possibility of going further in the utilization of the analyzer results by using a real-time material balance program to calculate the mass flow rates within the streams of a circuit for process control, analysis and optimization as well as for the detection of sensor malfunction. The material balance algorithm improves measurements and give good estimates of unmeasured variables during normal operating conditions. The potential and limitations of the method are illustrated using results of an application to the Line 3 flotation circuit of Brunswick Mining and Smelting, New Brunswick.IntroductionThe On-Stream Analyzer (OSA) has gained, over the last two decades, the status of key instrument for the control of flotation plants. The OSA is currently used in almost every sulphide flotation plant and its application in oxide mineral flotation plants isincreasing. Commercial OSAs include a sampling system that collectssamples from various streams of a circuit and exposes thesamples to an X-ray beam. The sample then generates X-ray pulsesthat are converted into assays using multilinear regression programs(Leroux and Franklin, 1994). The estimated assays arepassed to the flotation operators via operator consoles, or to controlloops of various degrees of complexity (McKee, 1991), whichmanipulate reagent addition, aeration rate or froth thickness toensure an adequate operation of the plant. Although this applicationrapidly pays for the purchase of the OSA, one should ask:""Could we get more from the OSA?"""

Jan 1, 1995

By Tweedy. D. H.

"The paper describes the rapid development of, and operational experience in the utilization of, pneumatic low-pressure pipeline hoisting systems to vertically convey raw coal and rock through shafts, supplementing shaft capacity-the greatest lift to date being 535 m.A typical installation has raised over 250,000 tonnes in less than one year from a depth of 413 m through a 350/ 400-mm pipeline at a rate of 85 tonnes per hour. Operational experience on seven systems has provided valuable data on performance and operating costs.The main advantages of the systems lie in the flexibility of the pipeline to occupy existing free space in shafts and underground roadways, the relatively low first cost, the short delivery and installation time, and the economical running cost.Conclusions are therefore reached on future applications for example, the use of boreholes in older mines where new production technology has outstripped shaft or slope capacity, inter-level hoisting to implement concentration on transport roads and perhaps full mine output from relatively small mines.IntroductionIt is seven years since the basic art and practice of the pneumatic hoisting of minerals was described. The technique was developed in Western Canada by Radmark Engineering and found favour in the United Kingdom with the National Coal Board. Engineering and commercial feasibility trails were conducted in collaboration with the Mining Department and Mining Research and Development Establishment of the N.C.B. There was also considerable involvement with the British Health and Safety Executive.During the last five years, rapid progress has been made in the installation of new systems in the United Kingdom, Hungary and other countries. The operational experience gained makes it possible to report ""in depth"" on these installations, which cover a wide range of different physical mining applications."

Jan 1, 1982

By D. G. Osborne

"The paper describes current &apos;tools&apos; available to the coal preparation engineer for carrying out the evaluation of data, process design, selection of equipment and layout and design of coal preparation plants.Laboratory and pilot-scale equipment is widely available and test data can be used to provide valuable design information regarding capacities and sizing for specific applications. Pilot plants, unless they fit closely to the basic design envisaged for the eventual commercial plant, C(In often provide only limited useful information.Computing aids such as equipment simulation, plant modelling, etc. are becoming widely applied for establishing design criteria and investigating flowsheet options . Other computer tools such as computer-aided design systems are taking over some of the time-consuming tasks of detailed layout and design and estimation of quantities, etc. and providing the means for detailed examination of more than a single option.Besides computer modelling there is also physical modelling of plant buildings, plant sites and entire proposed mining areas; the former can be especially useful in finalizing design and threading&apos; pipework and electrical reticulation systems through the plant without the resultant risk of impairment of flow, obstruction or wastefulness. Not the least of the benefits of plant models is the assistance provided for training new operating and maintenance staff."

Jan 1, 1985

By R. J. Mitchell

"The use of hydraulically delivered classified tailings sands to provide ground support in large mining operations is still widespread despite recent developments of alternate backfilling methods and materials. The major disadvantages of the use of hydraulic fill are the costs and risks associated with slurry delivery. The main risk is that of bulkhead failure resulting from sand liquefaction due to insufficient operational control or due to dynamic loading from earthquake or rockburst. That risk may be eliminated by the pouring of a stiff cemented sand plug in the base of each stope prior to continuous fill pouring in that stope. An additional advantage of cemented plugs is that massive bulkheads are not needed. Instead, a temporary (removable and reusable) bulkhead can be used for plug forming.Physical model studies of fill pressures on a temporary bulkhead were carried out in a 3 m radius centrifuge facility. Fill pouring in-flight was carried out in order to model prototype stress paths. The results indicate that the average bulkhead pressure is likely to be less than 10 kPa under normal operating conditions and less than 20 kPa under the poorest anticipated operating conditions which include smooth walls, high slimes content and high water-content slurries. A portable bulkhead consisting of a central core and a surrounding sealing bladder was modelled and found to be effective. The use of different sizes of cores allowed the stress distribution adjacent to these bulkheads to be evaluated."

Jan 1, 1992