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By G. P. Gormley

"Future open pit metallurgical coal mines in western Canada will be developed in complex geological environments. The success of these operations will be influenced by the mine operators' ability to prepare accurate mine plans and to predict and, subsequently, 10 control both out-of-seam dilution and coal recovery. Quintette Coal Limited has been mining its tightly folded and severely faulted Mesa depo sit at annual rates of up to 9 Mt of raw coal, since October 1982. Ongoing development drilling combined with continuous utilization of blast hole information, has been required to achieve an acceptable geological data base for short range mine planning. Thrust faulting has been a primary geological cause of difficulty in selectively mining waste and coal, which has resulted in higher than expected dilution in plant feed. The same geological phenomenon has also increased reserves by 6.3% and allowed for expanded mine plans to include a lower thrust plate, ultimately doubling the mines original reserve base. This paper illustrates the geology of the Mesa deposit and the type of work involved in its interpretation. Regional GeologyThe Quintette Coal Limited (QCL) property is located in the Peace River Coal Field of northeastern British Columbia. In this area, northwesterly-trending folds of the Rocky Mountain foothills are commonly cut by multiple, low-angle thrust faults, which dip to the southwest. The Lower Cretaceous Gates Formation, of near shore continental origin, contains 5 to 7 mineable seams of medium volatile bituminous metallurgical coal (Figs. I and 2). These seams normally range in thickness between 0.75 m and 9.5 m and have an aggregate thickness of between 15 m and 22 m."

Jan 1, 1988

By Y. X. Li, L. R. Xiao, S. Gong, S. S. He

Porous copper and porous copper based alloys with controllable pore structure have been manufactured successfully by sintering evaporation process. This process consisted of mixing copper or copper based alloys with NaCl powders, hot pressing and final high-temperature sintering to evaporate the filler material of NaCl powders. NaCl was eliminated completely during vacuum sintering, and strong metallurgical bonding in the walls was achieved. The pores’ structural parameter (pore size, shape, and direction) and porosity can be controlled effectively. These porous copper and porous copper based alloys with controllable pore structure have great potential in many fields. Including heat dissipating materials, heat absorbing materials, chemical catalyst carriers, electromagnetic shielding materials, filtering materials, damping materials, silencing materials, battery electrode materials. INTRODUCTION The development of porous materials began in the 1960s. The research of activated carbon with high specific surface area made porous materials enter the stage of material research (Belyakov et al., 2008; Ferey et al., 2008). With the rapid development of science and technology, porous materials play an important role in material research, and gradually become an indispensable part of the material research field (Wu et al., 2012). The research of porous materials has gradually extended to metal, ceramics, plastics and glass and other fields. It has been successfully applied in many fields, such as functional materials, industrial production, aviation, medical materials, biochemistry and electronics, which fully shows that porous materials have considerable development prospects. Porous silicon, plastic porous materials and glass porous materials are the most widely used in the field of non-metallic porous materials (Capelle et al., 2012). Compared with non-metallic porous materials, metal porous materials have developed rapidly in the late 1980s and become new materials with good mechanical properties and excellent physical properties. Porous metal materials have many advantages, such as large specific surface, small specific gravity, good silencing effect, high stiffness, high electromagnetic shielding performance, good shock absorption performance, etc (Li et al., 1999; Ferey et al., 2008). Among its many applications, metal porous materials can be used as both functional materials and structural materials. In some cases, metal porous materials have dual functions and structures. It is a multi-purpose engineering material with excellent performance. At present, porous copper, porous aluminium and porous nickel are the most concerned materials (Chen et al., 2002; Yang et al., 2017; Liu et al., 2018). The preparation methods of porous copper and copper-based alloys mainly include self-propagating high temperature synthesis (SHS), capsule-free hot isostatic pressing (CF-HIP), spark plasma sintering (SPS) (Kvanin et al., 2008; Takahashi et al., 2008; Zhang et al., 2014). However, these methods can not accurately control pore structure parameters (including pore size, shape, orientation, distribution, etc.). In porous materials, pore structure plays an important role in the overall performance of materials. In order to control pore structure parameters accurately and optimize material performance, it is necessary to explore and develop new preparation technology. In this paper, the sintering evaporation process (SEP) was introduced for the preparation of porous copper and copper-based alloys. The core process of the preparation method is hot pressing and evaporative desalination. Hot pressing can make the pore orientation consistent. Evaporative desalination can ensure the complete removal of NaCl in the form of vapor in a short time, thus eliminating the corrosion of residual NaCl on the matrix metal (Gong et al., 2011).

Jan 1, 2019

By K. P. Wright

THREE OF the gold mines in the Red Lake Camp operates fluid bed roasters in their milling circuits. The mines are Campbell Red Lake, Cochenour Willans, and Dickenson. The roasters are used for the autogenous roasting of a flotation concentrate for subsequent gold recovery by cyanidation. Cochenour and Dickenson operate single stage reactors, whilst Campbell use a two-stage system. Ore treated by the mines is similar in that the major part of the gold is associated with arsenopyrite. Other sulphides present are pyrite, pyrrhotite, stibnite and sphalerite. Gangue minerals are mainly quartz, with carbonates and talc. Mineralization is, for the most part, extremely fine, and there is intimate association between sulphides and quartz, so much so, th at a picked specimen of apparently massive arsenopyrite will frequently contain as much as 80 per cent gangue. Gold recovery by straight cyanidation on this type of ore would not be higher than 80 per cent and

Jan 1, 1961

By Sherwin F. Kelly

With the progressive exhaustion of ore deposits easily discovered by surface prospecting, the attention of scientists is being turned more and more to the employment of mechanical means for the location of ore bodies whose outcrops are not visible. The dip needle, the Eotvos Torsion balance, and various methods of electrical prospecting are illustrative of the modem tendency. Interest in the possibility of applying electricity to the solution of many of the prospector's problems dates much farther back than is usually realized. The first person to notice an abnormal intensity of electrical activity in the region of certain ore bodies was an Englishman, R. W. Fox, who experimented on the Cornwall copper and tin veins about 1830. Dr. Barus, in the United States, carried the early experiments a step further in his work on the deposits of Eureka, Nevada, about 1880. He made the very definite suggestion that the phenomena noticed would be of material aid to the prospector. Not until Professor Schlumberger, of the Ecole des Mines, Paris, took up the matter, shortly before the war, was any definite effort made to put electrical prospecting on a commercial basis. His work resulted in the establishment of sound principles and practicable field technique, for two distinct methods of prospecting.

Jan 1, 1924

By J. Oliver, B. Wilson, 10

"Red Dog is one of the world’s largest zinc producing mines and a significant producer of lead and silver. While some of the operational challenges relate to the mine’s location in a remote part of Alaska, there are also challenges in the mineral separation process. Recent processing upgrades have included the installation of two M5000 IsaMills to improve the zinc regrind circuit and of one Jameson Cell to improve the pre-flotation circuit. Relatively fine grinding is required to achieve efficient mineral separation at Red Dog, but while fine grinding aids in the production of high grade concentrates, it also creates challenges in the efficient recovery of fine minerals. Over half of the lead lost to the lead circuit tailings, as well as almost half of the zinc lost to the final tailings, is in the finer size fractions (<10 µm). The high pulp density experienced in the pre-flotation and lead rougher circuits also causes significant entrainment loss of lead and zinc to the pre-flotation concentrate and of zinc to the lead concentrate. To help improve fine mineral recovery, Red Dog has recently plant tested and installed magnetic conditioning technology in the flotation circuits. The equipment aggregates fine paramagnetic sulphides and selectively increases their flotation recovery. This paper outlines the testing and positive results at Red Dog.INTRODUCTIONRed Dog is the largest zinc mine in North America and represents approximately 29% of North American zinc concentrate production. The mine is located in northwest Alaska, approximately 100 miles north of the Arctic Circle and 50 miles inland from the Chukchi Sea. The remote location makes the mine accessible only by air or seasonally by ocean-going barges. Red Dog is a partnership between NANA Regional Corporation Inc, the land owner and Teck Alaska Incorporated, the operator of the mine. Red Dog Ore and Mineralogy The Red Dog deposit is a rich sedimentary exhalative (sedex) zinc-lead-silver deposit. The main minerals present in order of abundance are: quartz, sphalerite, pyrite, barite and galena. Production began in 1989 with mining of the Main deposit. Between 1989 and 2012, approximately 55.6 million tonnes of ore with an average grade of 20.5% Zn, 5.6% Pb, and 97 g/t Ag was mined from the Main deposit. Subsequent to the development of the Main pit reserve, two additional open pit deposits were discovered: Aqqaluk and Qanaiyaq. The first blast in Aqqaluk occurred on June 4, 2010. As of December 31, 2014, the Aqqaluk deposit reserve is an estimated 45.7 million tonnes of ore with an average grade of 15.1% Zn, 3.9% Pb and 71 g/t Ag."

Jan 1, 2016

By Jas. E. Thomson

PUBLIC attention was first attracted to the Crow River area of north-western Ontario by the discovery of gold in 1928. The first three discoveries were eventually developed into Central Patricia, Pickle Crow, and Albany River mines. In 1929, preliminary developments were carried out at the Howell vein on N.A.M.E. (later Pickle Crow) claims, and in 1929 and 1930 surface and underground work indicated an ore-body at Central Patricia mine. However, due to the financial depression and the distance of these properties from the railway, it was not until 1934 and 1935 that, benefitted by the revaluation of gold, the real potentialities of these two properties began to be realized. Their immediate success led to a resumption of activity on neighbouring properties throughout the area in 1936 and 1937. Preliminary prospecting in the earlier period had been limited by the scarcity of rock exposures in the country. The procedure in the recent programme of intensive exploration has been along similar lines at most properties and has consisted lf detailed geological mapping accompanied by geophysical surveys and followed by systematic drilling of favourable zones. The present importance of the camp may be judged by the fact that, in 1937, Central Patricia and Pickle Crow mines together produced bullion valued at $3,662,953, and paid $1,450,000 in dividends. In addition, there were pro-mising gold developments at Albany River mine. During the past two seasons, the Geological Branch of the Ontario Department of Mines has been making a fairly detailed study of the geology and mineral deposits in the Crow River area. It is the purpose of this paper to present a brief statement of some of the structural features of these deposits; a summary of other geological information essential for the understanding of the main topic is included. A more detailed report on the area will be published shortly by the Ontario Department of Mines. It is impossible to make full acknowledgment here for all help received, for the writer is in-debted to the management, staff, and consultants of every Company in the camp for generous co-operation in the field and for information, plans, maps, and records placed at his disposal. Reports and articles on properties in the area have been written by Hurst (1), Cormie (2), Reid (3), and the staff of Pickle Crow Gold Mines ( 4).

Jan 1, 1938

By Pierre St-Julien, Réjean Hebert, M. Racine, Roch Gaudreau, Pierre Lacoste, Michel Rocheleau

"Les unités volcano-sédimentaires de la ceinture de l'Abitibi à l’est de Val-d' Or ont été regroupées en quatre domaines litho tectoniques. Du nord vers le sud, nous reconnaissons les domaines d'Assup, de Garden lsland de Val-d' Or, de Trivio et de Villebon. Deux de ces domaines (Garden Island et Trivio) correspondent à des couloirs de déformation, d’envergure régionale et d’orientation approximative E-W. Les trois autres domaines sont caractérises par des volcanites defond océanique de type MORB (tholéiites et komatiites) qui sont en position inferieure; ces volcanites sont surmontées par des sédiments marins de type turbidite (domaine de Ville bon) ou évoluent dans le temps, soit vers un volcanisme bimodal d'affinités tholéiitique et calco-alcaline ( domaine d'Assup), soit vers un volcanisme d'arc insulaire (domaine de Val-d'Or). Il n'existe aucune certitude de corrélation litho stratigraphique entre les différents domaines et l'on doit considérer la possibilité que ceux-ci représentent l'accolage tectonique de terranes de nature et d'origine différente.Les principales caractéristiques structurales de la région sont regroupées en quatre étapes de déformation dont trois sont archéennes et la quatrième attribuée à l'orogenèse grenvillienne. Au moins cinq facies métamorphiques ont été reconnus: I) un facies régional faible propre à la province du Supérieur, 2) un facies de cornéennes a amphibole en périphérie du pluton de Pershing, 3) un facies hydrothermal dans la zone tectonique de Cadillac, 4) un facies régional moyen dans la zone de bordure de la province de Grenville, et 5) un facies régional élevé a l'intérieur de la zone structurale du front de Grenville.Le front de Grenville est défini dans la région par l’apparition subite des ortho gneiss au faciès métamorphique élevé et par la disparition du grain tectonique E-W. Le contact brusque entre les deux provinces pourrait correspondre à une zone de chevauchement de la province de Grenville sur la province du Supérieur. La région étudiée est l’hôte d’un gite majeur de sulfures massifs et de plusieurs gites et indices aurifères; elle présente des cibles favorables pour l’exploration minière dans le contexte tectonométa-morphique de l'influence grenvillienne. L'intérêt de la Formation de Val-d' Or pour les métaux de base et le potentiel aurifère des couloirs de déformation d'orientation approximative E-W, sont bien connus. Les structures grenvilliennes NE-SW, qui se développent vers l'est, représentent aussi des cibles intéressantes, en particulier dans les secteurs ou elles intersectent des cisaillements E-W kénoriens."

Jan 1, 1990

By C. Dupuis, P. Waite, S. Leboeuf

Casthouses throughout the aluminium industry commonly use chlorine gas as a fluxing agent for furnace and in-line treatment of molten aluminium alloys. Its positive impact on the removal of alkali elements and non-metallic inclusions is well known. Nevertheless, the elimination of its use is highly desirable due to the safety and environmental risks associated with storage and handling. Over the past decade, the aluminium industry has significantly reduced its chlorine consumption. This has been achieved by maximizing the chlorine gas utilization efficiency during metal processing, and by the chlorine replacement for crucible and furnace metal treatment applications. Operation of sealed in-line treatment units without chlorine is now possible, but with lower or inconsistent removal efficiency penalties for alkali and inclusions respectively. This paper reviews the progress made at Arvida Research and Development Centre regarding the reduction of chlorine and the development of an alternative to chlorine for in-line metal treatment without penalizing the metallurgical performance.

Jan 1, 2006

By D. B. Nazzer

"ANY DISCUSSION of energy today is incomplete without consideration of nuclear energy. In the Maritimes, with plentiful supplies of coal, with relatively easy availabilty of imported oil brought in to the deepwater terminals, with future sources of large supplies of oil and gas anticipated from under our neighbouring continental shelf, and with the Fundy tides, you may question why nuclear energy should be considered. What follows may not give you a specific answer to that question, but it may provide a basis for better understanding. Energy from the sun, from hydraulic sources and from combustion has been available to man from prehistoric times, for thousands of years, but the most sophisticated source of energy, the actual conversion of matter into energy by man, has been developed entirely within the last one-third century, since the discovery of fission in 1939, and the application to generation of electric power has all been done within a generation or less. The pressure of military needs during and after the second world war was largely responsible for the speed of initial development, by funding and focussing the effort needed to develop the basic technology, and in particular materials. The U.S. defence program yielded, for example, the large-scale isotope separation processes for fissile U'35 and for heavy water. The nuclear submarine program yielded zircaloy, a key structural material for the core of the Canadian Candu type reactor."

Jan 1, 1972

By Geo. D. Furse

"The information that has accumulated regarding the geology of the McIntyre mine is the result of work by several geologists and, as might be anticipated, their conclusions have varied. The writer has been at the mine only a few years and due to wartime conditions has not been able to study and review the mine's geology as thoroughly as his predecessors. Where the writer's conclusions differ from those of previous authors, it should be noted that he has been unable to re-map all the workings in which flow contacts are exposed, but has endeavoured to describe the structure as indicated by the evidence he has been able to observe. He wishes to thank H. G. Skavlem and H. S. Robinson for their constructive criticism of this paper, and McIntyre Porcupine Mines, Limited, for permission to present it. A list of references is appended.The McIntyre mine is in the central part of the Pearl Lake section of the Porcupine gold area. It includes the ""bed of Pearl lake, twenty-two claims to the north of the lake, and the Platt Vet lot to the southeast. It is bordered on the west by the Hollinger and on the east by the Coniaurum property. The chief ore-bearing veins on the upper levels lie very close to the north shore of the lake, but some occur under the lake, and others of lesser importance are found to the southeast. The most important veins are Nos. 3, 5, 7, 10, and 25. Some of the veins extend into the Hollinger. on the west and others cross the east boundary into the Coniaurum. The total production since the commencement of milling in 1912 to the end of March 1947 has been $168,448,218 in gold and silver from the milling of 17,690,963 tons of ore."

Jan 1, 1954

By A. R. Khodabandeh, T. Nematkhah

Correct selection of forging parameters is very important to produce sound superalloy parts. In this investigation nickel-iron base superalloy IN901 successfully forged and seal spacer, which is a part of airplane with about 11 kg weight has been produced. Forging has been performed on the basis of hot compression results, which show deformation above 1100°C associated with dynamic recrystallization (DRX) which can increase the workability of material. On the other hand annealing at 1100°C decreases the flow stress during hot compression, and then increases the material formability. Then billets annealed at 1100°C in electrical furnace for 24 hours and reheated again to 1100°C before forging. Initial square cross section billet with 128mm side and 202mm length forged immediately after reheating by 80MN mechanical press. Specimens forged in five steps: upsetting, three steps molding and finishing. Preformed and molded specimens reheated in electrical furnace before later step of forming. Finally specimens trimmed by 1 OMn mechanical press and hot set by hydraulic press and then cooled in air to room temperature. Results show that reheating temperatures has been selected correctly because there isn&apos;t any surface crack and die cavities filled completely by forging material. Material flow has been carried out properly and there isn&apos;t any defect in critical points especially in extradoses and intradoses. Microstructural examinations show that grain boundaries contain Ti-rich globular particles that formed during cooling.

Jan 1, 2006

By A. McEachern

At the Annual Meeting of this society, held in Halifax last year, a paper entitled "Closed System Breathing Apparatus" was read by I. C. Mackie, metallurgist, British Empire Steel Corporation. Coming from such an authority it was most instructive and illuminating. The purpose of the paper was to emphasize the necessity of a full supply of oxygen and the danger of oxygen shortage in the use of rescue breathing apparatus. In connection with this he pointed out: "In times of emergency, when life is at stake, rescue men cannot be restrained from using their utmost endeavor, and unless the apparatus is adequate to meet the heaviest load, the result may be fatal to the wearer. The body&apos;s demand for its oxygen requirement is absolutely imperative and must be granted at once. We can do without food for many days and without water for many hours, but we cannot do without full requirements of oxygen even for a few minutes. Furthermore, the victim of oxygen shortage gets practically no warning. He may fall helpless or unconscious before realizing that he is in a serious condition." Hence the necessity for expelling all the nitrogen from the breathing-bag and filling it with pure oxygen; also filling the lungs of the wearer with oxygen before he begins to use the breathing apparatus. This practice is general at all the collieries under the British Empire Steel Corporation.

Jan 1, 1924

By A. Klingberg, M. Svensson, N. Smolko Schwarzmayr

"Removal of silicates and carbonates from sedimentary phosphate ores by the use of new synthetic collector/formulations was investigated in a comparative study with traditionally used collector systems as references. In the direct carbonate flotation the new formulations showed higher efficiency, contributed to an improved balance of P2O5 recovery and P2O5 enrichment in the recovered material. Efficiency of the new formulations containing synthetic surfactants was 1.5–2 times better than potassium salt of fatty acid sulfonate based formulations that are traditionally used for that purpose. The new formulations also provided up to 7% increase in P2O5 recovery at the same P2O5 grade. The new synthetic collectors for removal of silicates showed extremely good selectivity towards silica bearing minerals. The selectivity factor for the flotation tests when new formulations were used was 32–52 and for the flotation tests with the traditional collectors: 20–32. The ratio between distribution of an amount of silicates (as SiO2) and distribution of phosphate in the froth (waste) is defined as the selectivity factor. The new formulations provided more than 2% decrease of the amount of SiO2 at the same P2O5 recovery.INTRODUCTIONPopulation growth and decrease of arable land are the main reasons for constant increase of consumption of apatite (phosphate ore) in the fertilization field (Lannefors, Gorochovceva, Klingberg, Lima, & Gustafsson, 2015). Fertilizers play a key role for farmers to produce more with less land. The phosphate component of the fertilizer is vital for producing healthy and large amount of crop. As a result the demand for phosphate rock is growing.The largest producers of phosphate rock are the Unites States, Morocco, Tunisia, China, Russia, and Brazil. The term “phosphate ore” includes all phosphate-bearing minerals and rocks, but only two of them are of industrial interest: apatite (igneous origin) and sedimentary phosphate (Peres, Araujo, El-Shall, Zhang, & Abdel-Khalek, 2007). The majority of the world’s phosphate deposits are of the sedimentary type. There are two different types of sedimentary phosphates: siliceous and carbonaceous which are categorized based on gangue minerals (such as quartz, carbonates, mica, and clay)."

Jan 1, 2016

By H. J. McQueen

Large-scale industrial production of pipe began with longitudinal hot pressure welding of wrought iron by passage of skelp (narrow strip with beveled edges) through a die or bell that curled it about a longitudinal axis until the edges were forced together. Such small to medium tubes could be reduced by rolling or drawing; with threaded connections, they were excellent for distribution of clean water and of illuminating gas for street, home and industrial lighting. Although steel lacks the fluxing slag for pressure welding it has hot strength similar to iron; hot-pressure bell welding was advantageously transferred to steel in long coiled strip with 50% higher cold strength. For pipe without weld-line defects, hot cupping followed by Pilger mill rolling produced tubing that revolutionized bicycle quality and high-pressure service for boilers and chemical processing. Mannesman hot rotary piercing produced long thick walled tube that permitted reduction or expansion by rolling to provide pipe sections up to 60 cm diameter and 12 m long. During 1910 - 1940, oil and gas pipeline technologies, notably welding evolved markedly as they proliferated in the United States, in response to far-flung petroleum fields, expanding industry consumption and the automobile revolution. In the Second World War combat pipelines were laid rapidly, such as: the Canol line through the Yukon to Alaska, and fuel supply lines across the channel and through liberated France. Perfection of welding techniques for both longitudinal and spiral weld large diameter pipe in combination with controlled-rolling of micro-alloyed steels made possible reliable Arctic pipelines. The development of pipe production and utilization in Canada is recounted. The fabrication techniques and metallurgical controls are explained.

Jan 1, 2005

Iron control and iron residue management and disposal are significant issues in all zinc production processes. This paper briefly reviews the most important primary zinc production routes and discusses the challenges posed by iron control in each of them. The technologies and strategies that have proven successful in controlling and managing iron are discussed. SNC-Lavalin&apos;s experience in designing and commissioning zinc plants provides a unique perspective from which to review this aspect of zinc production.

Jan 1, 2006

"AbstractThe Sedimentary Basin area of Western Canada, which lies between the Precambrian Shield and the Cordilleran mountain area, covers approximately 800,000 square miles. Sediments ranging in age from Cambrian to Tertiary are present and, of these, horizons in the Upper and Lower Cretaceous, Jurassic, Mississippian, and Devonian have yielded commercial oil and gas flows. Producing horizons in the Cretaceous and Jurassic are sandstone, while all those of the Palaeozoic are carbonate rocks such as red limestone or dolomite (bioherms). Shows of oil and gas have been encountered also in the Cambrian and Triassic sediments.The broad structural features of this vast expanse of sedimentary rocks are the Moose Jaw syncline, the Sweet Grass-Battle River arch, the Alberta syncline, the Foothills belt, the Rocky and Mackenzie mountains, the Great Bear-Slave Lake basin, and the Mackenzie Delta Basin area.This contribution outlines the .stratigraphy and structure of the Basin area, and gives examples of present producing oilfield structures and stratigraphic traps.Part 1.-Regional StratigraphyIntroductionThe vast expanse of relatively undisturbed sedimentary rocks of western Canada has long been recognized as prospective territory to search for oil and/ or gas. This search in western Canada dates back before the turn of the century, but, considering the size of area to be explored and tested, the effort an<l money expended upon it, which, before the recent discovery of oil at Leduc, Alberta, appeared large and fruitless, now seems almost ridiculously small. A check-up of effort and money expended prior to and since the Leduc discovery would undoubtedly reveal that more wildcatting and development has taken place during the last two and a half years than during all previous years combined. The figures would astound not only the average citizen, but many within the industry itself."

Jan 1, 1950

By David S. Robertson, Richard F. Douglas

"Uranium is a lithophile element of relatively low natural abundance. Concentrations of uranium form through processes of erosion and sedimentation, and over 90 per cent of the western world's uranium ore reserves are in sedimentary rocks.Proterozoic quartz-pebble conglomerates contain about 60 per cent of the known uranium reserves. These are all similar in appearance, in mode of distribution and in manner of origin. They carry uranium minerals and/or gold and abundant pyrite. Their unique distribution in Huronian time required a pre-existing crust well enough evolved to have plentiful quartz and abundant gold, uranium and pyrite. The materials of value were deposited as detrital heavy minerals prior to the appearance of an oxidizing atmosphere in late Proterozoic time.Epigenetic uranium deposits occur in arkosic sedimentary rocks through the entire geological column. About 30 per cent of the western world's known ore reserves are in _these rocks. This type of deposit is particularly prominent in semi-arid parts of the United States, having yielded most of the uranium ore produced and containing nearly all of the known reserves.The Western States type"" of deposits occur in lenticular, permeable stream-laid sedimentary rocks. The de-posits are believed to have been precipitated from moving ground water at locations where plant debris or other organic matter had accumulated. The uranium may be derived from volcanic sediments, which are commonly associated with the units containing the ore, or it may be leached from exposed granite surfaces or from granitic debris which forms the sediments.A significant part of the world's uranium resources are in black shales and lignitic rocks. The lignites that contain uranium are virtually valueless as potential sources of heat. Uranium concentrations at levels such as to be potential sources of by-product uranium occur in many phosphorites.Reworked sediments may provide uranium in pegmatites and vein-like deposits."

Jan 1, 1970

By D. Tao

The adverse effects of clay particles on coal and mineral processing processes such as gravity separation, flotation, filtration, and thickening are well known in the mining industry. In particular, the presence of ultra-fine clay particles deteriorates froth flotation performance, which has been attributed largely to slime coatings that inhibit bubble attachment and to adsorption of the frother and/or collector by the clay particles. The present study was conducted to evaluate the performance of clay binding agents developed by Georgia-Pacific Resins, Inc. in enhancing coal and mineral flotation performance. Mechanical and column flotation tests were carried out using coal and potash samples. Process parameters investigated include slurry solids percentage, impeller rotation speed, binder dosage, collector dosage, etc. Flotation results show that use of GP reagents significantly enhanced flotation efficiency under different conditions. The required binder dosage and conditioning time was about 1 lb/t and 0.5-1 min, respectively. More significant improvements in process performance were observed at higher solids percentage and higher impeller rotation speed.

Jan 1, 2006

By D. Farrish, W. A. Grell

"IntroductionMost base metal mines sell their concentrate to a custom smelter. The two parties concerned therefore draw up a contract which would detail the conditions under which concentrate sales will take place. The contract will identify treatment and marketing charges (including escalations), deductions for metal losses in the smelter, pricing formula, timing of payments, penalties for deleterious elements, etc.An understanding of the smelter contract is important to the mineral processor, for it will determine how he operates the plant to maximize economic return.Description of Contract ClausesUsing copper concentrate as an example, the smelter contract generally contains the following three basic charges:I. Metal Deductions- as the smelting process does not recover all the metal contained;2. A Smelting Charge- expressed per ton of material to cover costs on the bulk material such as receiving, unloading, thawing in winter, sampling, roasting to drive off sulphur, smelting through the matte and blister stages to recover mostof the copper and precious metals;3. A Refining Charge- expressed per pound of copper.The following is a review in some detail of a number of clauses which could be considered typical of a treatment and marketing type of copper concentrate sales contract. Most normal considerations in an agreement could be covered by the following types of clauses.Terminology- covers definitions, units of measurement to be used (e.g. short tons, troy ounces, etc.), currency (Canadian dollars). The term ""unit"" may be defined - l OJo of a ton of concentrate, e.g. one unit of copper means 20 pounds of copper per short ton of concentrate."

Jan 1, 1989

By Charles Graham

It is the general belief that the coal deposits on Vancouver Island are extremely large, and easily available. Indeed, they are frequently described by prominent public men and by writers in the press as "illimitable" and "inexhaustible." It is well that the facts that have been established as a result of seventy years of surface prospecting, underground operations and extensive diamond-drilling in this coalfield should be disclosed. HISTORY The presence of coal on the coast of British Columbia was first made known by Dr. W. F. Tolmie in 183 5. This coal was brought to him by Indians from the north-east coast of Vancouver Island, probably from Suquash. In 1850 the existence of coal at Nanaimo was announced by Mr. ]. W. MacKay. Development was started in 1852, and coal was shipped before the close of 185 3. The first operations were carried on by the Hudson&apos;s Bay Company, who operated the mines until 1861, when they sold them to the Vancouver Coal Mining and Land Company. Practically all of the operations in the immediate vicinity of Nanaimo have been carried on by this Company and its successors. In 1869, Mr. Robert Dunsmuir discovered coal about five miles north-west of Nanaimo, at Wellington. The Welling-ton Colliery Company was organized, and began to produce coal from the Wellington mines in 1871, the coal being shipped from Departure bay. This colliery was a large producer for several years, but was finally closed in 1900.

Jan 1, 1924