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By Paolo Farina

Slope monitoring radar has emerged in the last ten years as a leading edge tool for monitoring movements in natural and engineered slopes, thanks to its ability to rapidly measure slope movements with millimetric accuracy over wide areas in any weather conditions, obviating the need to install artificial reflectors. In recent years, slope monitoring radar has experienced significant improvements in its performances, mainly thanks to the use of different radar technology, such as Synthetic Aperture Radar (SAR), able to overcome some of the limitations of the first generation of radar and to provide higher spatial resolution, longer working distances and faster acquisition time. One of the leading applications of this technology is today represented by slope monitoring within the surface mining industry. Prominent international mining groups currently employ slope monitoring radar, based either on Real Aperture Radar (RAR) and SAR technology, for active and background monitoring of open-pit walls. The main technical features of typical slope monitoring radar based on SAR technology along with their possible applications are presented in this paper along with recent case studies of successful slope monitoring in open pit mines.

Jun 1, 2012

By T. R. Roy

"This paper presents an objective model for the estimation of fire risk potential of an underground coal mine panel by the bord-and-pillar method of mining where extraction is carried out by depillaring with caving. The fire risk rating procedure for the estimation of fire risk potential involved in the panel is described in detail. The model developed thereof is tested with the field data collected from different collieries across the country along with the laboratory data for critical assessment of fitness of the model. Some results showing the validity of the model are also cited here. Introduction The occurrence of fire in underground coal mine panels is quite common in India and elsewhere. These fires cause extensive loss of resources.Although substantial work has already been done by different research organizations, the problem has not been fully eliminated.The causes of panel fires depend not only on the spontaneous heating susceptibility of coal, but also on the extraneous conditions created in the panel due to the mining operations. From the studies done so far by various organizations, it is apparent that two types of parameters associated with spontaneous heating of a coal mine panel exist: intrinsic and extrinsic. Parameters related to the nature of coal, i.e., its physicochemical characteristics, petrographic distribution and mineral make-up are intrinsic, while the extrinsic parameters are related to the atmospheric, geological and mining conditions such as scope of leakage of air into the panel, wetness of mines, heat dissipation capacity of the panel, gassiness of seam, geological disturbances, method of extraction, size of panel, etc.Banerjee (1982) identified twenty-two mine parameters such as spontaneous heating susceptibility of coal, method of mining, geological disturbances, quality of overburden, degree of consolidation of coal mass, scope of accumulation of coal fines, etc. that can influence spontaneous heating in underground mines. He used the terms “high” and “low” for fire risk rating of each of these parameters. Since this approach is oversimplified, it can not determine the exact fire risk potential of an underground working."

Jan 1, 2003

By A. Ignatieff

This is the first in a series of Coal Technology Reviews being prepared in accordance with a recommendation voted by the Coal Division in session at the Jubilee Meeting, Vancouver, April, 1948, that the Department of Mines and Resources be requested to arrange for publication by the proper Government authority of a Quarterly Review' of Coal Technology, for distribution among those concerned in the production and use of coal in Canada. This recommendation was subsequently endorsed both by the Council of the Institute and by the Dominion Coal Board. Further reviews (or digests) will appear at intervals in the Bulletin, or will be published and distributed by the Board which, meanwhile, has undertaken to distribute reprints of Mr. Ignatieff's review.-En. * * * The fields in coal mining technology which are considered to demand most attention and study at the present time are reviewed under the headings appearing below. Mechanization In the light of the growing shortage of skilled miners and the necessity of mitigating constantly increasing mining costs, interest continues to centre in mining methods and applications of mechanization chat will produce the maximum reduction of man power. The growth of strip or open-cut mining, also, is a consequence of this trend. Mechanization at the face attracts most attention and the trend is toward developing and adopting machines capable of cutting and loading the coal in one operation instead of having the separate operations of cutting, drilling, blasting, and loading. In Great Britain, where longwall mining is? the general practice, the A.B. Meco-Moore machine still receives much attention, and accounts describing its performance over reasonably long periods have appeared in the technical press.

Jan 1, 1948

By Y. O. Fortier

"ForewordTHE Arctic Archipelago and northern Greenland contain an orogenic region that is as much as 300 miles wide and over 1,400 miles long. It occupies much of what was formerly classified with the Arctic Plains and grouped with other plains and lowlands of Canada as one main geological division. It is proposed that this folded region be designated the Innuitian Region and be recognized as one of the main geological divisions of Canada.Canada's main geological divisions (see Geological Survey of Canada, 1947) have been considered as consisting of a central shield, largely surrounded by plains that separate it from eastern and western mountains. The plains include the Interior Plains, the St. Lawrence Lowlands, the Arctic Plains or Low-lands, and the Hudson Bay Lowland, which is in the central part of the Shield. Plains and mountains are, strictly speaking, physiographic terms, but because mountains are generally folded regions and plains are generally made of undisturbed strata, such terms are useful vehicles to express the fundamental make-up of the land. Nevertheless, it is preferable to use the terms Appalachian and Cordilleran 'Regions' rather than 'Mountains', as those geological divisions are not exclusively made of mountains.Because of the lack of more definite information, the 'Arctic Plains' have included, in the past, regions with plateaux two to four thousand feet above the nearby sea, mountain ranges reaching approximately 10,000 feet above sea level, and regions of folded strata."

Jan 1, 1955

By H. L. Martin

A joint federal-provincial approach in gathering basic information from industry on mine production, concentrator operations and ore reserves, initiated during 1978, is a major step toward the goal of achieving better government-industry communication through a common data base. Information from questionnaires sent out by provincial governments is shared with the federal government; correct interpretation is ensured by mine visits conducted jointly by provincial and federal representatives. Initial focus is on nonferrous metal mines. The federal Department of Energy, Mines and Resources (EMR) is responsible for a national analysis that is aimed at the early detection of worrisome developments-and their reasons-in the flow from resources to reserves and from reserves to supply of these metals. The heart of the national analysis is the annual construction of a "monitoring curve", showing each metal's aggregated mine production as it would decrease over time if no new reserves and production capacity were to be added from the year of analysis. For a given metal, a comparison of monitoring curves from year to year can reveal early signs of supply stagnation. In anyone year, a monitoring curve in conjunction with foreseen needs for Canadian mine output will show the production gap that would have to be filled from reserves and production capacity yet to be developed. The production gaps for copper, nickel, zinc and lead, the four leading base metals mined in Canada, are shown for the 20-year period ahead, in the context of production achieved during the past 20 years. It is shown that reserve levels commensurate with likely future production levels would require that average annual reserve additions during 1978-98 exceed the average annual additions during the preceding 20 years. Reserve levels of all four metals have declined in recent years. A review of significant discoveries in the last five years suggests that this fall in reserves is not the result of a lack of exploration successes, but of stagnation in development for various economic reasons.

Jan 1, 1979

By M. G. Mena, M. S. Mena-Junio

Silver (Ag) filler is the most attractive choice among all the conductive fillers of die attach materials for the attachment of silicon devices because of its balanced properties and relatively low cost. However, a major problem of silver is that it electrochemically migrates in the presence of moisture and applied bias. In microelectronic devices, silver migration can occur between adjacent conductors/electrodes, which leads to the formation of dendrites and eventually results in short-circuit failure. In order to assess the reliability of these conductive fillers, an investigation for two types of Agfilled die attach materials was done using the water drop test at room temperature and using a 1000 hour temperature-humidity-bias (THB) test under 85 ºC and 85% RH conditions. Four different bias/voltages and six different electrode distance spacing were used. Both dendrite and cloud/lace-like growths were observed as a result of the electrochemical migration of silver, Water drop test results revealed that increasing the applied bias/voltage and decreasing electrode spacing causes migration to occur faster, thus resulting into shorter time to fail (TTF). It was also observed that the growth rate of the dendrites from the cathode increased linearly as the dendrite approached the anode, probably due to a combination of increased ion availability and electric field. A minimum applied bias of 3 volts was required for migration to occur in Epoxy A as compared to 2 volts for Epoxy C. The higher migration voltage requirement for Epoxy A was attributed to the higher volume resistivity of the said epoxy. In addition to the minimum voltage requirement, it was observed that a minimum electric field of about 1 volt/mm is required for migration to occur. The 1000 hour THB testing did not result into any failures. It is surmised that the presence of condensed moisture is another requirement for migration. Such condition is not present during the THB testing.

Jan 1, 2012

By J. S. Stachulak, K. A. Mackinnon

This paper deals with specifying and evaluating fans for mine ventilation projects. Topics such as fan and equipment design life, operating points, and operating conditions are discussed. Common operating problems, such as vibration, parallel operation, mechanical failure, erosion, corrosion, and deficient fan performance are covered. Apart from identifying the potential operating problems, likely causes and suggested remedies are given. Fan type, fan accessories, and likely system effects and fan testing are discussed. Suggestions on what should be covered when evaluating different fan options and proposals and suggestions on the verification of supplier claims and guarantees, including cost of operation, the evaluation of initial capital cost, estimate on maintenance costs, and likely replacement expenditure over the life of the fans. In addition, fan reliability, operational flexibility, suggested construction details and fan vendor past history and experience are reviewed.

Jan 1, 2004

By M. C. Bétournay

Under the requirement to define the economic advantages of using hydrogen fuel cell vehicles, a broad-scoped project was initiated to quantify the costs associated with operating fuel cell vehicles and diesel vehicles. While ventilation savings are clearly an advantage for the former, a complete and detailed analysis of this and other operational and capital cost elements was undertaken in order to provide the mining industry with factual information in considering the changeover from one technology to another. This paper outlines the results of the investigations to date defining the costs/benefits associated with capital purchases, operations (electrical/diesel, mine air heating fuel, ventilation, openings, surface and underground infrastructure, maintenance, labour, etc.), delivery of energy, regulatory obligations, and mine production. Considerations are given to the type and size of a mining operation, the depth, and location in North America. Significant ventilation power, equipment, and infrastructure savings are possible with the application of fuel cells for shallower mine applications. At depth, where heat is an issue, there is a reduction in benefit. Specific qualifiers such as minimum air velocities, dust dilution, shaft, and heating system velocity limits must be considered on an individual mine basis. While the capital cost for fuel cell mining equipment is currently higher than diesel versions, the high cost of fuel cells is anticipated to be reduced significantly in the near future with the intensification of manufacturing. In either case, the operational savings would probably be sufficient to balance the supplementary capitalization costs. Comprehensive reports have been issued.

May 1, 2005

By G. Righettini, G. Desrivières, P. Mousset-Jones, R. Lacroix, M. C. Bétournay, P. Laliberté, S. Hardcastle

"Under the requirement to define the economic advantages of using hydrogen fuel cell vehicles, a broad-scoped project was initiated to quantify the costs associated with operating fuel cell vehicles and diesel vehicles. While ventilation savings are clearly an advantage for the former, a complete and detailed analysis of this and other operational and capital cost elements was undertaken in order to provide the mining industry with factual information in considering the changeover from one technology to another.This paper outlines the results of the investigations to date defining the costs/benefits associated with capital purchases, operations (electrical/diesel, mine air heating fuel, ventilation, openings, surface and underground infrastructure, maintenance, labour, etc.), delivery of energy, regulatory obligations, and mine production. Considerations are given to the type and size of a mining operation, the depth, and location in North America.Significant ventilation power, equipment, and infrastructure savings are possible with the application of fuel cells for shallower mine applications. At depth, where heat is an issue, there is a reduction in benefit. Specific qualifiers such as minimum air velocities, dust dilution, shaft, and heating system velocity limits must be considered on an individual mine basis. While the capital cost for fuel cell mining equipment is currently higher than diesel versions the high cost of fuel cells is anticipated to be reduced significantly in the near future with the intensification of manufacturing. In either case, the operational savings would probably be sufficient to balance the supplementary capitalization costs.Comprehensive reports have been issued."

Jan 1, 2005

By C. P. Jenney

"Exploration for copper, in a region of 7,000 square miles on the Arctic coast between longitudes 114 and 118 degrees west, has covered a period of nearly 200 years. Occurrences of native copper, used by the natives for tools and weapons, have been reported since the early part of the eighteenth century. In J 771 Samuel Hearne of the Hudson's Bay Company, in the course of his classic 3-year journey from Fort Churchill, became the first white man to see the deposits, and incidentally the first to reach the Canadian Arctic coast by land. During the next 140 years the deposits were mentioned by every explorer and traveller who passed through the area. A good historical summary of this literature has been presented by Tyrrell (1912).In 1911-12 the Douglas-Sandberg party did the first geological mapping along the Coppermine River and Dismal Lakes (Douglas, J., 1913; Douglas, G. M., 1914), and described the copper occurrences there. In 1914 J. J. O'Neill (1924) of the Canadian Arctic Expedition investigated the showings on Bathurst Inlet. In 1929-31 two Canadian exploration companies sent prospectors and geologists to the area (Gilbert, 1931; Norrie, 1931; Duncan, 1931). Since that time only brief references have been published (Kidd, 1931; Stockwell and Kidd, 1931; Lord, 1941, 1951; Washburn, 1947). In 1943-45 an area of more than 1,500 square miles was prospected by American Metal Co. of Canada, Ltd., under the direction of the writer. Forty-nine showings were examined; seven of these were mapped in detail by plane-table and two were sampled by 27 short diamond drill holes totalling 3,061 feet. All holes were in permanently frozen rock, and the deepest vertical distance reached was 206 feet. Five groups of claims were staked. These later lapsed, but one of the groups was restaked in 1951, and assessment drilling and some trenching were carried out in 1952-53. Results were disappointing, and the claims have been allowed to lapse.The area is within the Arctic Circle, northeast of Great Bear Lake and 360 miles north of Yellowknife on Great Slave Lake. For exploration purposes, access is by aircraft from Yellowknife. During the short open season heavy freight can be brought by sea to Coppermine at the mouth of the river, either from Aklavik at the mouth of the Mackenzie or around Alaska. Concentrates would have to be moved by these routes.Although none of the deposits so far found is mineable under present conditions, the total volume of copper in the numerous showings marks the district as a major area of copper mineralization, which may some day be of economic importance."

Jan 1, 1949

"3.1. IntroductionAmong the six platinum-group elements (POE), four have identical cubic symmetry, two identical hexagonal symmetry (Table 3.1). Despite crystallographic differences, there is a clear relationship expressed in the chemistries of the POE: they tend to be mutually soluble in one another and can frequently substitute for one another in compounds with other elements. This chapter consolidates the data on phase relations of the POE and the compounds they form with elements selected for their known or potentially important mineralogical significance- As, Bi, Cu, Fe, Hg, In, Ni, Pb, S, Sb, Se, Sn and Te-together with selected data for the occurrence of POE in certain elements such as Au and Ag, and compounds such as FeS. Resources used to compile the data are those available from the chemical, mineralogical and metallurgical literature. First each element is discussed, with composition limits of solid solutions drawn from binary phase diagrams. Single element data are followed by a discussion of the relevant binary systems and a tabulation of data for binary compounds found in those systems (Table 3.2). Tables and diagrams for the ternary and quaternary systems for which information is available follow, and finally the very limited information on the solubility of POE in mineralogically important elements and compounds is presented.The chemical, mineralogical and metallurgical literature on the unary and binary systems is extensive and widely scattered in many languages and publications; fortunately, most of the data needed to compile this chapter can be found in reliable compendia. The most useful and most recent of these works is by Moffatt (1979), because it provides a ready index to all material relating to binary systems listed in previous compendia; furthermore, the Moffatt compendium will reportably be kept up to date by annual supplements."

Jan 1, 1979

By Liang Zhen, Jian-Tang Jiang, Guo-Ai Li, Xiao-Ya Wang

"Deformation behavior of 2A97 aluminum alloy containing coarse secondary phases was studied using uniaxial hot compression (HC, 340–490°C, 0.4001–1 s-1). The flow stress could be described by a Zener-Hollomon parameter in hyperbolic sine function with the hot deformation activation energy of 237 kJ/mol. Based on the experimental data and dynamic materials model, processing maps were generated to demonstrate the hot workability of the alloy. The coarse secondary phases experienced dissolution by varying degree under different deformation temperature, which producing different effects on the microstructure evolution. When deformed at relatively low temperatures, a mass of fine grains shaped up in the original grains and grain boundaries, and the dominating deformation mechanism was believed to be dynamic recrystallization. As the deformation temperature rising to 490°C, most secondary phases disappeared and few recrystallized grains were observed, indicating that the secondary phases dissolved sufficiently along with dynamic recovery occurred during the hot deformation. Particle stimulated nucleation related to the coarse secondary phases was believed to promote the recrystallization and the recrystallization behavior was sensitive to deformation temperature.INTRODUCTION Al-Li alloys has received much attention as new promising structural materials in the aircraft and aerospace industries, due to their lower density, higher elastic modulus and improved fatigue crack growth resistance in comparison with the conventional commercial aluminum alloys (Ou Ling, 2015). 2A97 alloy is one of the 3rd generation Al-Li alloys targeting at comprehensive improvement of aviation aluminum alloy and applications for wing spars and ribs to other internal structures for transport aircraft. Al-Li alloys are usually formed by hot deformation, either by rolling or extruding. The deformation behavior and resulted microstructure evolution during the forming process mainly dominates the formability of the alloy and the serving performances as well. Therefore, the deformation behavior and microstructure evolution at elevated temperature need be made clear for optimizing the hot processing parameters and controlling microstructure evolution."

Jan 1, 2018

By D. L. Thompson

Foreword The complete history and early development of the Sullivan mine was fully covered in a paper entitled 'The Development of the Sullivan Mine and Processes for the Treatment of its Ores', prepared by the staff of the Consolidated Mining and Smelting Company of Canada, and presented at the Annual Meeting of the British Columbia Division of the Institute at Trail in October, 1924. At a subsequent meeting at Blairmore, Mr. E. G. Montgomery read a paper on the mine, and in 1926 Mr. M. M. O'Brien brought the subject up to date at the joint meeting of the American and Canadian Institutes at Cranbrook. The present paper is necessarily based largely on these earlier accounts. Discovery and Early Development The outcrop was discovered in 1892 and the property was bonded and later sold to the Sullivan Group Mining Company, of Spokane. From 1896 to 1899, surface stripping and test pits (at A) around the outcrop exposed a vien of sulphides with varying amounts of lead and zinc. In some places, a 35 per cent lead ore carrying 15 ounces of silver was found. These lenses were of commercial value. With the completion of the Kimberley branch of the Canadian Pacific railway, in 1900, some systematic development was started. A shaft l00 feet in depth was sunk (at B). Shaft-house, boiler-room, and compressor-plant were erected, and a steam diamond-drill was put into operation.

Jan 1, 1929

By China University of Mining & Technology, Yuemin Zhao, Bo Zhang, Liang Dong, Zhenfu Luo, Chenlong Duan

"In China, approximately 65% of coal reserves are in the west region, where water shortage is a serious problem: high-efficiency dry coal beneficiation technology is desired. Using magnetic powder and fine coal as heavy medium, and using air as the fluidizing agent, a novel air dense medium fluidized bed separator is proposed for coal preparation. Coal can be efficiently separated according to density in the fluidized bed, where bed density is steady. The separator is highly reliable, the circulation quantity of heavy medium is low, and the gas distributor cannot be easily easily. The world’s first industrial modularized dry coal preparation plant was built by China University of Mining and Technology. Dry coal beneficiation technology was first used to produce low-ash coal. Results of industrial production show that the ash content of clean coal is 3.46%, the probable error E value is 0.055 g/cm3, and the organic efficiency is over 90%. The advantages of the modularized dry coal beneficiation system are the high separation accuracy, the simple process flow, the low operation cost, low energy consumption, and so on. This technology provides a new effective method for coal separation in acid region and coal tending to sliming.INTRODUCTIONCoal is the most important primary energy source in China, where coal output reached 3.68 billion tons in 2013 and represents approximately 68% of the primary energy consumption. Coal has made a great contribution to the development of the Chinese national economy, but it also brings serious environmental pollution. However, approximately 65% of coal reserves are in the arid west region in China where water shortages present a challenge for wet coal preparation technology. In addition, the abundant lignite resource, because it is easy to mud in the water, should not be treated with the wet separation method. Therefore, it is critical to develop highly efficient dry coal preparation technology to meet the demand in arid areas. Further, water resource shortages are a global problem, thus the development of efficient dry coal preparation technology in has potential application in other water-short countries like South Africa, Brazil, India and Turkey."

Jan 1, 2016

By A. E. Boudreau

Abstract-It has long been recognized that platinum-group-element (PGE) deposits in layered intrusions preferentially occur in intrusions that crystallized from high-Mg parent magmas. Recent studies suggest that evaluation of any given intrusion for economic PGE potential should also include assessment of the PGE, sulfur and chlorine concentrations in the cumulates and potential parent liquids. PGE: Magmas that contain relatively abundant Pt and Pd are the best candidates for forming economic deposits. Although analyses of coeval sills and dikes are the best indicators of primary magmatic PGE concentrations, analysis of the cumulates themselves is also valuable. For example, within the Stillwater complex, background PGE values in cumulates from the ultramafic sections of the complex contain, on average, several 10s of ppb Pt and Pd. Background concentrations of this order are suggestive that the magma was not depleted in the PGE. Sulfur: Conventional petrogenetic models for the formation of PGE deposits in layered intrusions require the PGE to have been concentrated during a magmatic sulfide-saturation event. In contrast, some hydrothermal models suggest that sulfur and the PGE were mobilized from footwall cumulates by upward- migrating, high-temperature hydrothermal fluids. Both models suggest that significant PGE deposits are likely to occur at and below the level where stratigraphic increases in whole rock sulfur concentrations occur. Chlorine: In both the Stillwater and Bushveld complexes the cumulate sequences below the major PGE-bearing zones contain anomalous Cl-rich apatite. The chlorapatite component of apatite in these rocks may exceed 40% and, in the Stillwater complex, typically exceeds 90%. It is stressed that pristine igneous mineral analysis and not whole rock data be used, as whole rock Cl concentrations may be affected by very localized (grain boundary), low-temperature alteration. Intrusions that crystallized from high-Mg, high-Cl magmas appear to have the best potential to host significant PGE deposits.

Jan 1, 1995

By Jean-Jacques Bouillon, Michel Jébrak, Stephane Faure

"Le gisement polymétallique (Cu-Zn-Au-Ag) des Mines Selbaie est forme par un réseau de filons encaisses dans une séquence de pyroclastites felsiques du sill on Harricana-Turgeon. Les minéralisations sont encaissées dans le tuf de Selbaie, situe sous une épaisse séquence d'ignimbrites Iitées. Ce gisement se distingue des autres gites archéens par une chronologie atypique des minéralisations: les veines de chalcopyrite, de sphalérite et de galène recoupent un amas exhalatifpyriteux stérile. Un vaste halo d'altération hydrothermale a chlorite et mica blanc est associe à cette minéralisation.La mise en place des veines minéralisées est associée à une phase d'extension NNW-SSE. Le complexe volcanique subit, par la suite, trois phases de déformation. Une compression, orienté N-S, développe une schistosité à peine pénétrative et un réseau de fentes de tension. Une réorientation des contraintes locales selon une direction WNW-ESE conduit au chevauchement de I' écaille d'andésite et de tonalite de Brouillan. Un réseau conjugue de failles normales cassantes est associe au relâchement des contraintes."

Jan 1, 1990

By G. W. H. Norman

"During the past few years emphasis has been placed on the importance of major faults, fault zones, and associated structures in localizing ore deposition. This interest has developed partly through experience in mining camps in other parts of the world, and partly by the discovery of such structures associated with ore deposits in the Abitibi region, northwestern Quebec. The recognition of these structures has been brought about chiefly by detailed mapping that has been gradually extended along most of the southern gold belt of Quebec and across adjacent parts of Ontario. In the Chibougamau region of northern Abitibi, progress has been made in mapping major faults by using aeroplane photographs with a scale of about 1,000 feet to 1 inch for field mapping. These studies have shown that many large faults occur in the Abitibi region; also that there is a relationship, direct or indirect, between faults and mineral deposition. The faults are, however, of more than one type and age, and this should be clearly appreciated in any planned programme for prospecting this great region adequately.Geology of the Abitibi RegionGeneral GeologyFaults of more than one age and type occur in the Abitibi region. In order to appreciate some of the age relationships of the faults, a brief summary of the historical aspects and major structural features of the geology (fig. 1) is necessary. These historical aspects may be briefly summarized in chronological order as follows:(1) Accumulation of Archæan lavas and associated pyroclastic rocks, either alternating with, or essentially followed by, deposition of sedimentary rocks, and interrupted at least once by local and perhaps regional folding and erosion."

Jan 1, 1954

By A. P. Paiva

The solvent extraction properties exhibited by some /V,N'-tetrasubstituted malonamides to efficiently and selectively recover iron(III) from concentrated chloride leaching solutions can be found in the recent literature. The iron(III) extractive chemistry exhibited by some of these derivatives is revisited, in order to compare their chemistry with that shown by a few of the new malonamide compounds. The generally good extraction efficiency towards Fe(III), from >4 M hydrochloric acid solutions, and the relative ease of Fe(III) stripping by distilled water are remarkable findings that are confirmed for the malonamide derivatives described in this work. Furthermore, additional data regarding their selectivity towards Fe(III) extraction over several base metal ions and their behavior when subjected to successive Fe(III) extraction-stripping tests are also presented and discussed.

Jan 1, 2006

By D. A. Barr

"Most of the lode and placer gold production in the Canadian Cordillera has been derived from mines and placers in the Intermontane and Omineca belts. Gold has been produced from rocks of Precambrian to Eocene age, but the preferred host environment contains Upper Paleozoic to Upper Jurassic eugeosynclinal or arc-type sedimentary and volcanic rocks adjacent to plutonic complexes which have a wide variety in both size and composition. Auriferous quartz lodes occur in fissures and shear zones which are commonly subsidiary to strong fault zones. In common with most vein-type deposits, structural complexities are an essential part of the mine environment.Gold production from the Canadian Cordillera to the end of 1978 totals 35.0 million ounces, of which 47 per cent has been produced from placer mining, principally in the Klondike and Cariboo districts. The balance has been derived from lode gold (80 per cent) and base metal (20 per cent) mines.Gold reserves in producing mines and deposits committed for production as of January 1, 1978 were 87.4 tons, or 21.6 per cent of total Canadian gold reserves contained in all types of deposits. Although more than 100 lode mines have operated in the Canadian Cordillera since the turn of the last century, over 75 per cent of the lode gold produced by 1978 was recovered from five mining camps, namely the Rossland, Hedley, Bridge River, Premier and Barkerville.The average grade of the principal producers in these camps was about 0.45 ounce of gold per ton. Individual camps yielded from 3 to 8 million tons during their operating lives, which varied from 28 to 43 years. The last of these mines ceased operating in 1971.Most of the total lode gold production has been derived from quartz veins, frequently with associated carbonate and ankerite, occupying fractured and faulted zones in Mesozoic volcanic and sedimentary rocks closely associated with a variety of intrusions. A review of the literature suggests that several deposits may have evolved by remobilization of ore constituents from earlier concordant gold-bearing formations. The principal metallic minerals in the deposits are native gold, electrum, tellurides, pyrite, arsenopyrite, pyrrhotite, sphalerite, galena and chalcopyrite.As the mineralogy suggests, many of the Cordilleran lode gold deposits have yielded important co-products or byproducts, including silver, copper, lead, zinc, cadmium and tungsten. Significant by-product gold production has also been derived from porphyry copper, volcanogenic, replacement and pyrometasomatic deposits, particularly in recent years.No major lode gold discovery has been made in the past 67 years, although little exploration activity for gold has taken place during the last 30 years. Several relatively small lode gold and gold replacement deposits have been discovered in recent years, either serendipitously (Chappelle) or on very low initial budgets (Northair and Carolin). Based on well-established precedents, one or more of these may eventually be developed into a large mine.A detailed study of the Canadian Cordillera gold deposits based on recent genetic models could prove rewarding, not only in up-dating information on their origin and depositional characteristics, but in stimulating the search for undiscovered gold deposits, in the Cordillera and other parts of Canada."

Jan 1, 1980

By Julian Wills

The Candrill was developed with Soredem as a one-operator rockdrill for Canadian narrow vein mining. It provides the benefits of increased drilling rates, lower noise and vibration, mass reduction of 20% and system cost saving. The Candrill is to be commercialised at the end of 2001 together with a stoper drill through Parts Headquarters, Novatek's Canadian agent. The Candrill or pneumatic drills may be further exploited using a simple mechanised drilling system to further reduce operator labour, improve drilling speeds by up to 50% and to enhance drilling accuracy. Novatek's drilling system for simple mechanisation in gold and platinum mines is integrated with roof supports, can operate in stope widths as low as 800 mm and has resulted in labour savings of 50%, improved advances per blast of 20 to 50% and improved operator safety and ergonomics.

Oct 1, 2001