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By John J. Laffin

"Nova Scotia Department of Mines and Energy Throughout the history of Nova Scotia, trends in the production and use of its coal resources have resulted in major impacts on the economy and society of the province. Current trends in coal demand locally, nationally and internationally are having and will have an increasing positive effect on Nova Scotia over the next twenty years-in terms of energy supply, job creation and general economic development. Coal for electrical generation is an immediate and key objective of Nova Scotia's energy plan; and, in the long term, coal-derived fuels will meet the province's needs for transportation fuels. Demand for metallurgical coal is also expected to increase, especially if the merchant coke plant currently under investigation becomes a reality.Meeting these coal supply and utilization objectives in the face of increasing environmental, social and economic constraints poses a tremendous technical challenge. Work has begun on projects to expand coal production capacity and to adapt new technologies for coal preparation and utilization to the specific needs of Nova Scotia; much more work will be required in the coming decade in order to succesfully tap this resource.IntroductionThe energy problem facing Atlantic Canada has a few unique features not found in the rest of the country. Canada, as a whole, has access to a diverse mix of energy resources, including crude oil, natural gas, coal, hydro and uranium, with the result that crude oil supplies only about 40 per cent of Canada's primary demand. In contrast, foreign crude oil dominates Atlantic Canada's energy mix, supplying over 70 per cent of the primary energy demand.This results in important differences in various sectors. Nationally, about 5 per cent of the electricity is generated from oil whereas last year in Nova Scotia approximately 40 per cent of the electricity generated was from imported oil. Residential, commercial and industrial space heating, and industrial process heating in Atlantic Canada was almost 100 percent dependent on foreign oil. This is in sharp contrast to the situation in central and western Canada, which have access to secure domestic natural gas, oil and hydro electricity."

Jan 1, 1982

By A. R. Miller, R. A. Stanton, M. J. Male, G. R. Cluff

"The Dubawnt Group consists of continental sedimentary and volcanic rocks which fill structural depressions - Baker Lake Basin, Yathkyed Lake and Angikuni Lake subbasins- whose evolution was controlled by late Aphebian extension, between 1.9-1.8 Ga. Structurally controlled uranium mineralization having the signature U + Mo + Ag + Pb + Cu ± Zn is spatially related to (i) intersecting fault systems that record multiple movements, (ii) chemically reactive lithologies containing sulphide, chlorite or graphite/ carbonaceous matter in the Archean and Aphebian basement complex and as alkaline volcanics of the overlying Dubawnt Group and (iii) areas containing thick successions of basal Dubawnt Group red clastic sediments.The most significant uranium occurrence found to date is the Lac Cinquante deposit, which contains 14 million pounds U3O8 of drill-indicated reserves. Mineralization is hosted in Archean meta-volcanic and metasedimentary rocks of the Henik Group adjacent to the basal Dubawnt unconformity in the northeastern A ngikuni Lake subbasin and occurs as plunging pods in and peripheral to a fractured and brecciated tuffaceous meta-sediment- sulphide+ carbonaceous exhalite. This deposit exhibits many features typified by the classical vein deposit at Beaverlodge, northern Saskatchewan.Epigenetic stratabound U + Cu + Ag ± Mo mineralization, typified by the 74-1E prospect in the eastern Baker Lake Basin, is hosted in thermally altered Kazan redbeds adjacent to alkaline dykes.At the eastern end of the Baker Lake Basin, small prospects having an elemental signature U + Se + Cu + Ag +Au are interpreted as unconformity-related mineralization associated with the Helikian The/on Basin.The Dubawnt Group rocks of the Baker Lake Basin, subbasins and adjacent basement complex contain uranium mineralization of two eras- Late Aphebian and Helikian."

Jan 1, 1986

By D. Assmus, S. Daly

"Poor fragmentation, high toe areas, excessive shovel wear and tear and frequent re-drilling and blasting of certain tough waste rock zones in the Lomex pit in the early 1980snecessitateda better understanding of these zones.A combination of geotechnical mapping, penetration rate data, toe elevation contouring and observations on shovel and drill performance were used to determine the character and extent of these zones. This complementary information was brought together by the geotechnical mapper and the explosives supervisor.Distinct zones with particular geological characteristics were determined. A classification system with three types of blast and dig-ability was developed for the Lomex pit and later applied to the Valley pit, with considerable success. The three blast zone types are called ""poor"", ""f air"", and ""good"". This system will be described in detail.The explosives supervisor adjusted the blasting parameters to each zone, in particular, pattern spacing and burden. The resulting powder factors showed considerable variation between the poor, fair and good zones within each pit as well as between the two pits. Pattern geometry and length of collar were also adjusted to improve fragmentation. Cost savings resulted from less re-drilling and less wear and tear on drills and shovels in the poor zones and more efficient use of explosives in all the zones. An annual estimated cost savings of well in excess of $1,000,000 is realized at Highland Valley Copper. A by-product of the mapping was the determination of unstable structures and water flowing zones. Blasting was then adapted to this information for enhanced slope stability."

Jan 1, 1992

By S. G. Coultis

Turner Valley is in the foothills of the Rocky mountains, at an altitude of 4,000 feet, and is 42 miles south west of Calgary. The present producing area is 8 miles long by 1 1/2 miles wide, while drilling is being carried on over an area of 10 miles by 2 miles . There are 32 wells producing, 26 wells drilling, and 17 wells shut down, making a total of 75 wells, which range in depth from 2,160 feet to 5,900 feet, varying according toa the well location on the anticline centre wells being shallower than those located on the flank. The first indication of possible production in this field was a gas seepage on the banks of Sheep river, in what is now the Royalite plant yard (Figure 1). Geologically, this seepage proved to be located on an anticline running through the valley in a southwesterly direction. The Calgary Petroleum Products Company was formed in 1912, and under the direction of Mr. A. W. Dingman, President, and associates, the first well was drilled. Production was obtained in this well. Gas was found in several horizons from 884 feet to 3,960 feet, and oil at 1,557, 2,718 and 3,839 feet. In May, 1914, oil was struck at a depth of 3,839 feet, this being a light straw-coloured oil of 60 gravity, which was blown spraying from the well accompanied by three to four million feet of gas. The latter contained some 200 grains of hydrogen sulphide per 100 cu. ft., giving it the disagreeable odour so well known in Turner Valley gas. This strike caused considerable excitement and started the famous 1914 boom, when some 400 oil companies were formed. The well referred to produced from two to five barrels of 60 gravity oil per day, and 4,000,000 cu. ft. of gas. The oil was used in the crude form in cars and trucks.

Jan 1, 1929

By J. E. Hawley

"The zinc-lead deposit of the Lake Geneva Mining Company is on lot 7, con. VI, Hess township, Sudbury district, Ontario, about 10 miles northwest of the northern rim of the Sudbury Basin. Though a relatively small deposit, it shows some rather interesting relations to cross-cutting, pre-ore, quartz diabase dykes, which merit description.The deposit was discovered in October 1924 by J. H. Collins beneath iron-stained drift and oxidized sulphides. This proved to be the northwestern extremity of the orebody, the remainder of which extends southeast below swampy ground. Exploration began in 1927. In 1928 a vertical shaft was sunk to 250 feet and a level established at 235 feet. Later the shaft was deepened to 400 feet and new levels opened at 315 and 375 feet. In 1943 an inclined winze was sunk below the vein from the 315-foot level to a vertical depth of 640 feet, and two additional levels were opened at 525 and 615 feet respectively.The geology of the area has been described by T. T. Quirke (1), F. F. Osborne (2), F. J. Alcock (3), and Ralph Tuck (4). Private reports have also been made by Carl Tolman, J. E. Gill, and K. W. Fritzsche. Tuck's paper, covering the work completed to 1930, gives a detailed account of the character of the ore and enclosing rocks.Up to May 1944, when the property was closed, all ore above the 375-foot level and a small tonnage from below this elevation had been removed. Ore mined from 1941 to 1944 yielded the following:"

Jan 1, 1954

By A. Brown

IN INTRODUCING the subject of rock pressures, it may safely be assumed that mining men are only too familiar with the physical effects of strata stresses that accompany the extraction of minerals. It may be further assumed that they have, as individuals, arrived at certain conclusions regarding their nature, based upon years spent in observing such phenomena and in learning how to continue mining in spite of them. Such hardly won experience forms the core of what is often referred to as 'pit sense'. This essential type of knowledge is not ?based on theoretical considerations, nor can it be found in text books. It is highly individualistic in nature and almost impossible to pass on from one generation to another in terms of precise rules for guidance. It is this aspect of individual judgment based on practical experience that has led to the significant phrase The Art of Mining.

Jan 1, 1956

By N. Ginouse, S. Reny

"In the mining industry time is critical as production depends on the speed of the mining cycle. During the mining process, the time required to re-open access for the next phase of an underground heading is a key point that strongly depends on the ability of the selected ground support technique to promptly ensure the safety of workers. Fiber reinforced dry-mix shotcrete has been proven to be an efficient and well adapted technique, able to produce a ground support material with the required energy absorption or flexural toughness in a single application phase. In this context, this paper demonstrates the possibility of significantly speeding up the mining process by using a new fiber reinforced dry-mix shotcrete. The new fiber reinforced dry-mix shotcrete is capable of developing flexural toughness in only 24 hours that is equivalent to what is typically achieved after 28 days using current fiber reinforced drymix shotcrete technology.INTRODUCTIONShotcrete is often used for ground support when using the drill and blast method or other tunnelling methods. But before re-opening access for the next phase of the underground heading, the applied shotcrete is required to reach a minimum compressive strength and in case of fiber reinforced shotcrete, a minimum flexural toughness (energy absorption) in order to ensure the safety of the workers going into the heading. Combined with bolts, the use of conventional fiber reinforced shotcrete becomes an interesting method for ground support as it is applied very soon after excavation and works to stabilize ground movements (Bernard E. S., 2009). In this case, the toughness development of fiber reinforced shotcrete becomes an important feature of the material when looking to speedup the mining cycle. However, early re-entry criteria in underground openings are difficult to ascertain as the load carrying capacity of fiber reinforced shotcrete is usually assessed after 7 or 28 days. For this reason, re-entry criteria varies from one mining area to another and are usually based on compressive strength requirements. For example, in northern Ontario, Canada, one of the current practices in the mining industry consists of allowing safe re-entry once fiber reinforced shotcrete has developed a compressive strength of higher than 4 MPa (Dufour, O’Donnell, & Ballou, 2003). Flexural toughness requirements on fiber reinforced shotcrete are also typically based on evaluation after 28 days."

Jan 1, 2015

By C. Overton, R. W. Nice

"With todays economic trials and tribulations we have all become deeply engaged in costs and cost cutting in our field of mineral processing. Grinding is one of the most expensive unit operations. The cost of grinding media is the most expensive item in grinding costs. Therefore, it is only reasonable to attack the cost-cutting area by trying to reduce the consumption of media. This introduces the field of autogenous or rock-on-rock grinding.Rock-on-rock grinding is not new to us. It has been known for many decades;The South Africans used pebble grinding in the '20's for gold.Mr. B. Crocker was prompted for the same reasons to introduce pebble grinding at Lakeshore Mines in Kirkland Lake during the last war.The Buffalo Anchorite used beach pebbles in grinding prior to the war.Autogenous and semi-autogenous grinding is used quite successfully in the iron ore field. Base metals have their examples in Australia at Caba, in Africa at Komato and in Sweden at Aitik.Recently three mills in British Columbia and one in Arizona started with autogenous mills in their circuits. One was originally conceived to utilize a modified autogenous grind with a crusher in the circuit. All except the same mill had contingency plans for converting to semi-autogenous. All four mills have since converted to the semi-autogenous mode. These are Island Copper, Lornex, and Similkameen in B.C. and Pima Mining in Arizona."

Jan 1, 1975

By G. W. Govier

The origin and limitations of the conventional and empirical equation for the interpretation of the results of back pressure tests on gas wells are discussed. Difficulties in data interpretation arise from many causes, including Jack of flow stabilization, uncertainties in connection with the friction calculation, and the effect of turbulence near the sand face in the reservoir. A procedure is developed to ac-count for the turbulence effect. This is based upon the theoretical equation for laminar steady state flow and current knowledge of turbulent steady state flow. The procedure involves the expression of the equation for combined laminar-turbulent steady state flow in terms of a turbulence contribution factor. This factor. is shown to be dependent mainly upon the flow rate per unit of pay thickness and the reservoir permeability. The method of interpretation permits the use of judgment based upon the theory and present day under-standing of laminar-turbulent flow and is considered an improved method

Jan 1, 1961

By W. G. Campbell

"The region discussed comprises approximately eight million acres spreading across the Arctic Circle in Yukon and North West Territories.Encouraged by four years of surface geological and geophysical work, which strongly suggested that suit-able conditions existed for the entrapment of oil and gas, a decision was reached to drill. In due course two holes were drilled; Eagle Plains No. 1 drilled to 9589 in 1957-8 and Western Minerals Chance No. 1 spudded in 1959 is being deepened this year.Thick sections of sedimentary rocks occur on both sides of the Richardson Mountains, however, most of our activities have been concentrated to date on the west side in the Eagle Plains basin. Here are found stratigraphic units ranging from Precambrian to Tertiary age. The drilling of the two exploratory wells proved the presence of these strata at depth and have confirmed the presence of promising structures. A geological cross-section across Eagle Plains presents an interpretation of these conditions.Physical and engineering aspects of exploration in the northern Yukon and North West Territories are de-pendent largely upon seasons and transportation. Reconnaissance gravity and surface geologic mapping by air presents no serious problems. However, seismic operations on the ground are greatly affected by the season, presence of permafrost and mobility of equipment.The actual drilling of the hole may well be the simple part of a wildcat undertaking once equipment and supplies are on location. Over-all planning, assembling supplies, transporting equipment and personnel seems to be the real job. Serious consideration must be given to per-ma-frost effect in the drilling pro-gram and on surface installations as well.Programming for -the various exploration activities should be under-taken well in advance of the actual doing. Considerable extra costs may be the results of crash programs. Costs are high, and the rewards uncertain. Economic evaluation is based •on the long term outlook."

Jan 1, 1960

By Gérald Riverin, Bernard Salmon, Marlo Gagnon, Réemi Asselin, Alain Cazavant, Michel LaBrie

"The Ansil deposit is located in the Noranda mining camp in the southern part of the Abitibi greenstone belt. /twas discovered in 1981 and production began in 1989 with proven reserves of 1.58 Mt grading 7.2% copper, 0.9% zinc, 26.5 glt of silver and 1.6 glt of gold. It is centered at a depth of 1.3 kilometre and represents one of the deepest ore discoveries ever made from surface.The deposit consists of a single massive sulphide lens located at the contact between the Northwest Rhyolite and the Rusty Ridge Andesite. The lens strikes north-south and dips 50° east. The thickness of the lens may reach up to 35 m and can change very abruptly both along strike and along dip. The maximum thicknesses of the sulphide lens are reached in its upper (western) and at its lower (eastern) edges, thus giving the deposit its present shape of two sulphide domes connected by a thinner central portion. The lower dome is underlain by a thick accumulation of massive magnetite which may reach 10 to 15m in thickness. The upper and lower domes are underlain by two distinct pipe-shaped zones of stringer and disseminated sulphides which merge with a larger stringer zone at depth.The Ansi/ deposit displays strong relationships between its morphology and the distribution of metals. Hydrothermal alteration consists of chloritization and sericitization. Chlorite alteration is closely associated with stringer sulphide mineralization while sericite is developed in diffuse zones bordering the chloritic zones. Unlike other similar deposits, the Ansil deposit is characterized by very extensive alteration and sulphide mineralization in the hangingwall of the massive sulphides. Several features of the deposit are consistent with an origin from a submarine hydrothermal system which was particularly long-lived, and which thus promoted the build-up of very high fluid temperatures with extensive replacement (and enrichment) of pre-existing sulphides after their original deposition onto the seafloor."

Jan 1, 1990

By J. E. Armstrong

"IntroductionT'HE PRODUCTION of gravel and sand may be considered to be the major mining operation in the Lower Fraser Valley of British Columbia. At least thirty pits are in operation with a yearly production probably in excess of two million yards and a value in excess of one million five hundred thousand dollars before crushing, washing, and sizing. The value of the finished products would probably be double the above figure.Since 1949, the writer and his co-workers have been engaged in the geological investigation of the Lower Fraser valley and adjoining Coast mountains for the Geological Survey of Canada. The study, which is not yet completed, includes both bed-rock geology and geology of the unconsolidated sediments lying above bed-rock. In a rapidly expanding industrial area, .an advance knowledge of the geology may• greatly aid in future 'planning, and in many cases may .prevent not only the wastage of large sums of money, 'but possible disaster. Some of the present and future applications in which geological information in the Lower Fraser valley should be of value are as follows: the development of domestic, irrigation, industrial, and municipal groundwater supplies; drainage for industrial sites,, roadbeds, and farmlands; flood control along the Fraser river and smaller streams in the area; the location of dam sites, of major tunnels for water supply •and sewage, of road-beds, of foundation sites for large buildings .and other engineering undertakings in which geology may aid; the evaluation of oil and gas •possibilities; the production of building stone; and the production of sand and gravel, the subject with which this paper is primarily concerned."

Jan 1, 1953

By F. A. Auld

"Traditionally deep shaft sinking from the ground surface was carried out using drill and blast methods. Although large diameter blind shaft drilling has been carried out successfully on numerous occasions previously, including as early as 1852 in Germany (Auld, 1995), little attempt has been made until more recently to mechanise the shaft sinking excavation process using down-the-hole machines. This paper reviews the development of deep shaft sinking machines from the early 1970’s up to the present day. INTRODUCTION Mechanical excavation methods can significantly improve excavation performance, in order to access natural resources faster, and labour safety is increased compared to drill and blast operations. However, shaft sinking machines need to be capable of accommodating all the basic requirements for deep shaft sinking, namely: 1. Excavation and muck removal 2. Ground stability control 3. Groundwater ingress control 4. Temporary lining installation 5. Permanent lining installation and watertight sealing 6. Ventilation 7. Secondary means of egress for personnel In addition, how the machine operates in the shaft is an important factor, either slung on ropes from a surface headgear or on its own in the bottom of the shaft. An all-embracing machine which can deal with all of the above conditions is impossible but many of these requirements can be incorporated into a single machine. Deep shaft sinking also differs greatly from normal tunnel construction which employs the use of either a roadheader arm installed within a shield or a full-face tunnelling machine for excavation. Hydrostatic pressure and ground stability problems increase with depth, whereas in tunnelling the depth is normally relatively shallow and the aforementioned factors remain approximately constant along the tunnel length. DEEP SHAFT SINKING MACHINES All the shaft sinking carried out previously in the UK was by the traditional method of drill and blast. Elsewhere, in other parts of the world, attempts have been made to mechanise the process."

Jan 1, 2019

By A. J. Reed, W. R. Bergey, Carr. J. M.

"The Highmont copper-molybdenum deposits are at Gnawed Mountain in the Highland Valley porphyry copper district, 125 miles northeast of Vancouver. This district is near the center of the lower Jurassic Guichon Batholith, where a north-trending swarm of porphyry dikes is crossed by west-northwesterly structural belts in which fracturing, intrusion of porphyry and breccia, and mineralization areconcentrated.The Highmont deposits are 2 miles southeast of, and in the same southernmost structural belt as, the Lornex deposit. The main deposits occur on either side of a composite dike of granodiorite, porphyry and breccia which strikes west-northwestward in fractured quartz diorite. North of the dike, the adjacent Nos. 1 (East) and 2 (West) zones together contain 150 million tons of open-pit ore mineable in two separate pits. These two zones will support a 25,000-tpd mill with a grade in the first five years of approximately 0.46 per cent copper equivalent. South of the dike, the Nos. 3 and 4 zones are partly explored and will provide large additional reserves. In these various zones, chalcopyrite, bornite and molybdenite form disseminations and fracture-fillings accompanied by quartz, K-feldspar, tourmaline, sericite, specular hematite and other minerals. Bornite extends for varying distances north of the dike, beyond which chalcopyrite is locally accompanied by pyrite. Higher-grade mineralization tends to coincide with fracture swarms, or with shear zones and faults which largely parallel these swarms. The ore zones are reflected by geochemical soil anomalies which show some glacial dispersion. LP. surveys gave weak but significant responses, expressed as per cent frequency effect. The ore zones occur within a strong magnetic gradient, but do not show a significant magnetic response."

Jan 1, 1971

By David S. Robertson

"IntroductionCanada has been one of the world's leading producers of uranium since atomic energy first became of practical importance in 1942. Indeed, prior to this time, between 1933 and 1940, Canada produced significant amounts of pitchblende, as a source of radium, from the Eldorado Mine at Great Bear Lake*.Uranium was first reported in Canada, however, in the middle of the 19th Century in the vicinity of Theano Point on Lake Superior north of Sault Ste. Marie. In the early 1900s, uranium-bearing minerals were reported in Quebec north of the St. Lawrence River and in pegmatites in Quebec and eastern Ontario. In 1930, G.A. LaBine and E.C. St. Paul visited an occurrence of cobalt reported by the Geological Survey of Canada in 1900, and brought the Eldorado Mine into production in 1933, as noted above, producing, in the main, silver and pitchblende.In 1942, developments in atomic energy were such that the Government of Canada, at the behest of Great Britain and the United States, requested that Eldorado, which had been closed in 1940, be re-opened to produce uranium for the Manhattan Project. In September, 1943, all discoveries of radioactive minerals were reserved to the Crown and their staking by private interests was banned. In January, 1944, the government nationalized Eldorado and formed a Crown corporation, the present Eldorado Nuclear Limited, to take over the assets. That year marked the formal beginning of uranium exploration in Canada.The Period 1944 to 1948In 1944, the Crown Corporation and the Geological Survey of Canada began exploring for uranium deposits, largely in the areas of Great Bear Lake and Lake Athabasca. In that year, A. W. Joliffe of the Survey visited properties on the north shore of Lake Athabasca near Beaverlodge Lake and recommended that Eldorado acquire claims in the area. In 1946, P. St. Louis and E. Laurum, prospectors working for Eldorado, found the pitchblende veinlets that led to the Ace Mine. Shaft sinking began in 1951, and production, through a carbonate leach plant, began in 1953.Continuing drilling on the Eldorado claims led to the Verna ore bodies, some 6,000 feet northeast of Ace, on which shaft sinking started in 1954."

Jan 1, 1986

By R. C. Rowe

THIS paper is an endeavour to analyse the ideal and practical functions of government technical mining services, and their relationship to the National Domain, as well as to one another. its spirit is not critical, even though at times it may appear to besoin fact. It is a serious effort to divert a trend in public thought which delights in calling itself practical whereas it is really merely short-sighted. The author refers particularly to the idea that governmental research is a luxury which should be curtailed in the interests of economy, and turned over to private enterprise or the provinces. In order that we obtain the proper perspective of the question, it is advisable to indulge in a little history. In the year 1842, the Geological Survey of Canada was formed under the guidance of William (later Sir William) Edmund Logan. The literature on the founding and history of the Geological Survey of Canada is extensive, and therefore it is unnecessary to go into detail here regarding it. It might be mentioned, however, that the Geological Survey of Canada is only seven years younger than the Geological Survey of Great Britain (founded in 1835), and is only exceeded in age on the American continent by the State Geological Surveys of New York, Pennsylvania, Massachusetts, and Michigan, which were founded between 1833 and 1836. In 1877, the Geological Survey became a permanent government institution as a branch of the Department of the Interior. It should be noted, however, that the Director of the Survey ranked as a Deputy Minister and reported direct to the Minister. This continued until 1907. In 1886, the Mineral Resources and Statistics Division of the Geological Survey was formed. Some years later, the Canadian Institute of Mining and Metallurgy (then the Canadian Mining Institute), backed by the mining press, began to agitate for the establishment of a Dominion Department of Mines, and in 1907 such a department was founded by the Geology and Mines Act of that year, with a separate Cabinet portfolio for the position of Minister of Mines.

Jan 1, 1939

By Dean S. Rogers

"In February 1980, Dome Mines Limited announced a $50 million expansion program which would result in a 50% increase in mill capacity from the present 1,815 tonnes per day to an eventual production rate of 2, 720 tonnes per day in the year 1984. As an integral and necessary part of this planned expansion, a new vertical production shaft, No. 8 Shaft, would be sunk from surface to a depth of 1,645 metres.Throughout the seventy-year history of mining at the Dome, gold has been found in a number of different rock types and in association with a number of different structural settings. However, the key to successfully locating ore deposits lies in the recognition of the favourable environments in which they generally occur. First and foremost, the exercise of locating the No. 8 shaft became an exercise in geological deduction based on the projection of these favourable lithologic environments.In November 1980, after detailed engineering work was completed, the total cost of the project was estimated at $75.5 million 1980 dollars or $91 million dollars allowing for inflation over a four-year construction period. These estimates include the shaft, significant replacement and alterations to the milling process, and an upgrading of the plant."

Jan 1, 1982

By Nicola Robjohns, Kenneth A. Grace, Jane Spooner

"The important volume end use sectors for the rare earth elements and yttrium continue to be in steelmaking, petroleum cracking catalysts and glass polishing. The market sectors which may provide future high volume demand, to replace the older sectors where demand has declined over the past decade, include magnets, automobile catalysts, ceramics and superconductors. Increases in production capacity in all major rare earth producing countries are expected to restrain large price increases for high purity rare earth oxides over the short term. A sharp increase in demand for yttrium in advanced ceramics and superconductors would lead to a shortage in separation capacity, however, and to a corresponding rise in prices for separated rare earths.IntroductionWhile visiting the Geology Department of the University of Toronto in 1981, Professor Lu from the Institute of Geochemistry of Academia Sinica at Gweiyang in China introduced one of his seminars with the observation that in China, rare earths are not rare at all.Indeed, while being rare in terms of abundance as measured by, say, the Clarke scale, the rare earth elements, like many other low abundance elements, are subject to geological, geochemical and mineralogical concentration.The rare earth elements comprise the fifteen inner transition elements of Group IIIB, Period 6, of the periodic table, from lanthanum to lutetium (the lanthanides), as set out in Table 1. The rare earths constitute a distinct group as they have extremely similar chemical characteristics due to the uniformity of their outer electron shells. The element yttrium is usually, by convention, included in the rare earth group as it occurs with the rare earths in nature and has properties very similar to them.The rare earths are divided into two subgroups, the ""light"" rare earths, made up of the first seven elements of the series, lanthanum to europium, and the ""heavy"" rare earths, comprising the remaining eight elements, gadolinium to lutetium, plus yttrium. These two subgroups are also referred to as the cerium subgroup and the yttrium subgroup, respectively. The subdivision is based on differences in the atomic radii resulting in somewhat different properties for the two subgroups."

Jan 1, 1991

"The Code was developed in 2004 through the Collaboration Agreement between Institution of Mining Engineers of Chile (IIMCh) and the Ministry of Mining (Chile) in Dec 2002. It is an amalgamation of current practices with respect to standards and procedures for exploration prospects, mineral resources, and reserves for the purpose of public reporting. Certification is required to prepare and issue information on mineral assets according to the guidelines that regulate the technical, economic, and environmental aspects that satisfy the conditions set by the Chilean capital and financial markets.The Mineral Resources Committee of the Instititution of Mining Engineers of Chile (IIMCh) is pleased to introduce theCode for the Certification of Exploration Prospects, Mineral Resources and Reserves which is the result of a Collaboration Agreement between the IIMCh and the Ministry of Mining established in December, 2002.This code synthetizes the present practice of the mining industry in regard to standards and procedures applied to exploration prospects, mineral resources, and reserves with the purpose of reporting publicly on financial instruments based on these mine assets in the capital markets. These standards follow general criteria already adopted and applied by capital markets in those countries characterized by a very dynamic and well developed mining sector such as Australia, Canada, Southafrica, United Kingdom, and others. The work done by the Mineral Resources Committee of the IIMCh has had the recognition of the Combined Reserves International Reporting Standards Committee (CRIRSCO) that leads the establishement of an international code in these matters. CRIRISCO is an entity formed by representatives of the countries previously mentioned, a representative of the Society of Mining Engineers of the UStates and a representative of the IIMCh. The Institution thanks the Ministry of Mining, the representatives of these Ministry in the Mineral Resources Committee, and specially the Minister of Mining, Sr. Alfonso Dulanto Rencoret due to the genuine support given to the IIMCh in the preparation of this Code.The Institution also thanks the Superintendencia de Valores y Seguros (SVS) because of the help given continuously to the Committee as well as by the interchange of opinions and suggestions received during the preparation of this document."

Jan 1, 2003

By J. J. Emery

There is an increasing awareness on an international level of the potential for utilizing many wastes and by-products as construction materials. This has resulted in recent major reviews by OECD and RILEM to supplement national activities by agencies such as CANMET, USBM, BRE and LCPC. Much of this international and national work was reported during an International Conference on the use of by-products and wastes in civil engineering held in November 1978 in Paris. Based on participation in the OECD and RILEM reviews, and the Paris conference, developments in waste and byproduct utilization of particular concern to Canada are described. The major technical and economic constraints involved are also reviewed, so that the over-all evaluation reflects important factors such as inherent variability and transport logistics. Areas requiring further research and development are also identified. Particular emphasis is placed on slags, salvaged asphaltic concrete and surplus sulphur. "Due to the rapid development of China's industry, more than a hundred million tons of industrial wastes are generated annually, which occupy lots of land for storing, bring about environmental pollution, obstruct industrial and agricultural production and cause harm to people 's living. Therefore we must utilize them effectively to create wealth for our country. "

Jan 1, 1979