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By S. Mostaghel, V. Hernandez, S. Ge

"The automotive industry is under a constant pressure to reduce the weight of vehicles in order to reduce emissions and improve fuel efficiency. As such, there is an ever-growing demand for high strength and high ductility steel grades to meet the need for lightweight automotive components. Over the past decade, the production and application of 2nd and 3rd generation Advanced High Strength Steels (AHSS) as a lightweight material in automobiles has gained significant popularity due to their exceptional mechanical properties. However, the production cost of these high manganese steel remains high, partially due to the need of large amounts of ferromanganese as alloying material in standard steelmaking processes.The current study introduces a new and cost-effective technology for the production of medium- and high-manganese steels, where self-fluxed micro-pellets of manganese ore will be used as the source of manganese that can be injected into the steel bath. Prior to injection, these pellets are subjected to a pre-reduction process using a mixture of H2 and CO gases, where partial metallization of iron and manganese will occur. Direct injection of the pre-reduced micro-pellets provides less volatilization/emission and higher recovery of manganese, and is capable of producing AHSS with 6–18 wt% Mn.INTRODUCTIONAutomakers are constantly searching for lighter, stronger and cheaper materials in an effort to create safer and more fuel efficient vehicles. The introduction of aluminum alloys and polymer composite materials for automotive applications has been carving into what is traditionally one of the most profitable markets of the iron and steel business. The steel industry responded with Advanced High Strength Steel (AHSS)—a family of manganese containing steels which exhibit exceptional strength and ductility."

Jan 1, 2016

By J. -F. Lepage, M. A. Tomlinson, K. K. Murray

"The Éléonore mine, located in the James Bay region of Northern Quebec, generates a gold bearing flotation concentrate rich in pyrrhotite. Direct leaching of the finely ground concentrate results in high cyanide consumptions and poor recoveries, so effective pre-treatment to passivate the pyrrhotite is required before leaching. Following a number of process upsets at the mine, test work was performed to better understand the requirements for passivation so a more effective operational strategy could be implemented. This paper outlines the testing and implementation of the new strategy at Éléonore.ÉLÉONORE CONCENTRATOR The Éléonore mine is located 800 km north of Montreal, in the James Bay Region of Quebec, Canada. The ore, containing gold disseminated in sulfide minerals and free fine gold in silicate gangue, is crushed in a two-stage crusher plant before being ground in a single 9,000 kW ball mill. The ball mill is in closed circuit, with about 25% of the cyclone underflow passing through a gravity plant with two, 48” Knelson concentrators. Gold recovery in the gravity circuit varies between 15 and 20%, with gravity concentrate leached daily in an Acacia intensive leach reactor. Cyclone overflow, at a target P80 of 65 microns, flows to the flotation plant where the gold bearing sulfide minerals, mainly pyrrhotite and arsenopyrite, are recovered to concentrate with a mass pull of about 5%. The flotation concentrate, typically containing between 80 and 120 g/t of gold, is thickened and finely ground using a 1500 kW Isa Mill. The finely ground concentrate is diluted, to generate a slurry with about 32% solids by weight, before feeding the leach plant. Initially the concentrate slurry is pre-treated with oxygen and lead nitrate, to passivate the sulphide minerals before cyanide is added for gold dissolution. Gold is recovered from the leached slurry using carbon-in-pulp (CIP). The flotation tailings are also thickened and gold is recovered in a dedicated leach-CIP plant."

Jan 1, 2017

By J. E. Shigley

The gemological properties that allow natural emeralds and blue sapphires to be distinguished from other gemstones are summarized in this paper. A variety of synthetic and laboratory-treated emeralds and blue sapphires are also encountered in the jewelry industry today. Gemologists distinguish these latter materials from their natural counterparts based primarily upon features seen with magnification, such as inclusions and/or growth zoning. In some cases, however, these observations and standard gem-testing methods are insufficient, and the use of non-destructive analytical methods, such as optical spectroscopy and chemical analysis, are required for positive identification. The commercial value of synthetic and treated gems are much less, and can be insignificant in comparison to that of an important untreated natural gemstone. Identification of synthetic and treated gem material is essential to maintaining integrity in the jewelry industry. Loss of consumer confidence in the gemstones sold at the jewelry counter could have a negative impact on the exploration and mining of natural emerald and blue sapphire.

Jan 1, 1998

By R. Cammack

"A fundamental component of the Hoek–Brown empirical rock failure criterion is assessing an appropriate mi constant. In developing their empirical criterion Hoek and Brown normalised triaxial test results by dividing the principal stresses at failure by the uniaxial compressive strength to provide mi values for typical rock types. Experience shows that Hoek triaxial tests for individual lithology types commonly have a large inherent scatter. In addition, tests are often conducted on core from random locations, which although being of one parent rock type, display variations in density as well as minor variations in grain size and alteration.This paper presents experience from projects the authors have been involved in which large sample populations of triaxial and UCS tests on similar rock types were available. Geophysical logging data was also available for some projects. The methods used to estimate the compressive strength for each sample and the effects on normalising the data sets are described. The variability of the data and uncertainties and assumptions involved in the process of assigning a mi value from the normalised data are also discussed."

Jan 1, 2015

By Roy S. Celland, K. H. Singh

The introduction of 'post' pillar mining at the Strathcona mine represents a new approach to ground support in cut-and-fill applications. The method has also shown significant economic advantages. It is believed that the development of this concept is one of the few examples where rock mechanics principles have successfully been applied in the development of a stoping method. The paper describes the evolution of this method and contains discussions on the theoretical analysis of the technical, operational and economics aspects of the system. Pillar design procedures and field observations on the practical application of theoretical analysis are also outlined.

Jan 1, 1973

By Dalton. J. L., H. P. Dibbs

An account is given of investigations into the application of two neutron methods to the on-line analysis of slurries. One deals with the application of the neutron moisture gauge principle to the determination of the water content of iron oxide slurries, and the other with the application of gamma radiation from thermal-neutron-capture to the determination of the composition of aqueous slurries of iron oxide, copper oxide, zinc oxide and sulphur. Linear relationships were found between the composition of the slurry and the neutron count-rate in the first study, and between the slurry composition and the prompt-gamma-ray count-rate in the second study. A mathematical relationship has also been developed which relates changes in the prompt-gamma-ray counts from hydrogen to changes in slurry composition.

Jan 1, 1973

By Witold J. S. Ostrowski

The shaft structure being part of an underground mine, depends on programned functional duties, and on geological and hydrological conditions. The majority of Canadian metal mine shafts are in hard competent igneous rocks, which are in an elastic state of equilibrium around the excavation. Others penetrate soft sedimentary or very weak water-bearing rock formations in which the equilibrium varies from plastic to hydrostatic. Knowledge of how to interpret the underground conditions, determine acting forces and design proper structures is essential for the production and safety of the future mine.

Jan 1, 1973

By C. A. Sosa-Blanco

Minera Sabinas in central Mexico treats a complex sulfide ore containing galena, chalcopyrite, sphalerite and argentite as valuable minerals, and in some cases important amounts of non-magnetic pyrrhotite. For high pyrrhotite ores, results obtained by selective flotation showed good grades and recoveries in the lead-copper circuit, but a commercial zinc concentrate could not be produced due to the high floatability of pyrrhotite. When this is the case, an alternative method was proposed to produce a bulk concentrate by flotation which is then leached to recover copper and zinc from liquor in a SX-EW circuit. Leaching was conducted in an autoclave in order to study the effect of temperature and pressure, but bioleaching tests were also conducted. Leaching lead-silver residues were treated by cyanidation in order to recover silver values. The results obtained by selective flotation and by bulk flotation with leaching of the bulk concentrate showed that the latter alternative increased zinc recovery by 30 % with similar recoveries of the other metals.

Jan 1, 2007

"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 M. Kreuh

Crystalline Mg(OH)Cl and amorphous Mg2(OH)3C1 were successfully isolated from a hydrolyzed molten salt electrolyte sample in this work, It was found that the chemical form and crystallinity of the hydroxylchloride were controlled by the cooling rate of the molten sample when it was taken. Crystalline Mg(OH)Cl could only be obtained by cooling the molten electrolyte sample at a rate not faster than 0.6 °C/min, Upon more rapid cooling, the hydroxylchloride species precipitated as Mg2(OH)3Cl, The behavior of these solid hydroxylchlorides when contacted with fresh and non-hydrolyzed molten electrolyte at 550°C was also examined, It was found that the Mg(OH)Cl rapidly dissolved in the hot electrolyte and did not decompose into MgO at that temperature as would be expected from the literature, The dissolution rate of solid Mg2(OH)3Cl was found to be so slow by comparison that it resulted in the complete decomposition into MgO which thereafter was incorporated into the electrolyte as a suspended solid phase rather than dissolution.

Jan 1, 2004

By S. Esfahani, M. Barati

Heat recovery from blast furnace slags is often contradicted by another requirement, to generate amorphous slag for its use in cement production. As both the rate and extent of heat recovery and slag structure are determined by its cooling rate, a relation between the crystallization kinetics and the cooling conditions is highly desired. In this study, slags with different basicities were studied during non-isothermal cooling. Their continuous cooling transformation (CCT) diagram were plotted and compared with each other. Then, a mathematical model was developed that predicts the amount of crystallization during cooling. The results were validated by experiments performed by Single Hot Thermocouple Technique and image analysis. A second mathematical model that calculates temperature history of slag during its cooling was coupled with the above model, to allow optimizing the slag/air ratio for both heat recovery and slag glass content.

Jan 1, 2015

By T. L. McCall

CHANGES in mining practices have evolved so quietly and unobtrusively that perhaps we scarcely appreciate how truly startling these changes are unless we cast our minds back so as to compare the past with the present. Such retrospection is, indeed, necessary when attempting to forecast the future, for it is only by carefully reviewing the past that we can hope to obtain an indication of what the future may hold in store. In this instance, it is not necessary to delve into the very early history of . coal mining, as our purpose will be served if the last three or four decades are reviewed, a period that is still fresh within the memory of many of us. These earlier days might be termed the selective period of mining, for at that time the coal resources of the world had not been tapped to anything like the extent they are at present and this condition enabled the owners and operators to exercise selective powers and only mine such seams of coal as could be most easily reached an worked at the lowest possible cost and which, at the same time, would suit the requirements of the market. Carrying this thought of selective mining still further, the miner, who was then an artisan skilled in all the branches of his calling, was able to select or discard such parts of the seam he was working that the co al sent out of the mine was acceptable to the consumer with just the barest minimum of preparation. Compare these conditions with the? conditions prevailing today, when coal seams of medium height, good quality, and readily accessible have been largely depleted and the operator has been compelled either to carry on his operations under much greater depths of cover where the coal is more costly to win, or else to work seams of lesser height or of poorer quality.

Jan 1, 1938

By B. M. Das, F. Claridge, V. K. Garga

Coal, as well as a large part of other minerals in Canada, is produced by surface mining methods. This has resulted in short and long-term accumulation of waste rock in dumps. Two main problems arise from the flow of water through these dumps: stability of dumps and the impact on stream flows. In recent years, a number of mines have started placing waste rock in valleys for general disposal or far constructing mine access road ways. All these have created challenges in the following areas: effective design of dumps and flow-through dams; stability monitoring of the structures; environmental impacts downstream by way of increased amount of fines in suspension, sedimentation, and toxic substances; and long-term status of flow and flood. Similar situations also exist in many civil engineering structures. This paper discusses the status of rock drains and the immediate and future research needs.

Jan 1, 1990

By Descarreaux. Jean

"The Abitibi volcanic belt was sampled along a cross section extending from Matagami to a point east of Rouyn. A few samples were also collected in Louvicourt township, Quebec. The major elements were determined for 344 samples, and rock names were defined using normative minerals. The analytical data were studied by means of variation diagrams. The Abitibi volcanic belt is characterized by rocks belonging to both the tholeiitic and calc-alkaline magmatic series, but they show some differences as compared to some typical reference series, particularly those from Japan. Basalt is the predominant rock type and accounts for 44 per cent of the sampled outcrops. The volcanic rocks are relatively poor in K2O and TiO2. Regionally, the volcanogenic copper-zinc mineralization is associated with the calc-alkaline volcanic sequences. Locally, within such sequences, some types of abnormal deviations from the averages are recognized only in association with the copper-zinc mineralization. The anomalies are ascribed to hydrothermal alteration consisting of the introduction of MgO and removal of N a20; enrichment in K20 is also observed where zinc mineralization predominates. Examples of such anomalous zones show that, in places, this alteration phenomenon can be quite extensive. Petrochemical characteristics can be used as geochemical ore guides in exploration programs."

Jan 1, 1973

By Qingxia Liu, Mingbo Zhang, Hongbo Zeng

The shortage of freshwater has been a major challenge for mineral flotation in arid areas. When using high salinity water, certain electrolytes are detrimental to flotation while others can improve the flotability of minerals. In this paper, the flotation behaviors and contact angles of pyrite in both Milli-Q water and high salinity water were investigated using different collectors at various pH levels. Results show that the thionocarbamate has a less affinity to pyrite in different solutions under mildly alkaline conditions as compared with potassium amyl xanthate (PAX) and N-isopropoxypropyl-N’-ethoxycarbonyl thiourea (iPOPECTU). At high pH levels, the slime coating on pyrite surfaces, which is caused by colloidal precipitates of magnesium and calcium ions in seawater, was confirmed by SEM, EDX and in-situ zeta potential measurement. The slime coating of colloidal precipitates on mineral surfaces led to low recovery of pyrite at high pH levels. The study of flotation behavior of pyrite in high salinity water improves our fundamental understanding of mineral flotation in seawater.

Jan 1, 2015

By Rodney A. Cooper

The Mary River iron ore deposits were discovered in the 1960?s. The high quality of the deposits was immediately evident, and drilling programs were successful in defining a resource adequate for supporting a feasibility study. Through a combination of ownership, market and political forces, the deposits were not developed. Having missed the window of opportunity, the project remained dormant for over three decades. Baffinland Iron Mines Corporation, with its 100% ownership of the Mary River deposits, began trading publicly in 2004. Modern exploration and metallurgical test work began in 2004 and has continued in 2005 and 2006, resulting in total expenditures during this period of almost C$60 million. In May 2006, an engineering team lead by Aker Kvaerner E&C, a division of Aker Kvaerner Canada Inc., completed a scoping study based on the first of five identified deposits. Highlights of that study include direct shipping of high quality lump ore to Europe over a 34 year mine life at a production rate of 10 million tonnes per annum, based on an indicated resource of 309 million tonnes at 66.1% Fe and an inferred resource of 28 million tonnes at 65.9% Fe. Capital costs were estimated at C$1.5 billion. Using iron ore prices approximately 36% below that of the 2006 market, a pre-tax internal rate of return of 15% was estimated assuming equity financing. Payback on initial capital was 5.9 years. The pre-tax life-of-mine cash flow was estimated to be C$6.3 billion. As a result of this study, Baffinland initiated a Definitive Feasibility Study, under the management of Aker Kvaerner, which is scheduled for completion in December 2007. This paper touches on the geology of the deposits, the current resource and the outlook for expansion. Project permitting, construction planning, logistical challenges and ocean shipping considerations are discussed, providing a current perspective on the project scale, scope and timeline for commercial production. In addition, an overview of the Company?s bulk sampling program will be provided.

May 1, 2007

By J. E. Armstrong

THE Pinchi Lake mercury belt is in central British Columbia, about fifty miles north of the Prince Rupert branch of the Canadian National railway (Figure 1). Until 1936 little was known about the geology of this area. Jn 19~6 and 1937, J. G. Gray and the writer mapped the Fort Fraser area (G.S.C. maps 630A and 631A) for the Geological Survey of Canada. During the field season of 1937, cinnabar was discovered by J. G. Gray in the Permian limestones on the north shore of Pinchi lake on what have since proved to be the main showings of the Pinchi Lake mercury mine. Claims were staked in the spring of 1938 and later that year were optioned to the Consolidated Mining and Smelting Company. Development work revealed cinnabar deposits of commercial size and grade, and a small reduction plant was erected, production of mercury commencing in June, 1940. Since 1940, this plant has been enlarged by additional units. The ore treated is reported to contain between 0.5 and 0.75 per cent mercury. The production of mercury from this deposit is now far in excess of Canadian requirements and this country is able to supply the United Kingdom with part of its needs. In 1940 and 1941, several other occurrences of cinnabar were found northwest of Pinchi lake. During 1941, the writer made a geological investigation of the known cinnabar occurrences and of the belt of country in which they are located. The present paper summarizes the results of this work. The writer is indebted to officials of the Consolidated Mining and Smelting Company, and to Mr. E. Bronlund of the Pinchi Lake mine in particular, for their generous co-operation in the work.

Jan 1, 1942

By A. F. Banfield

"IntroductionELEMENTAL sulphur occurs in three types of deposits: in salt domes in the Gulf Coast region of the United States and Mexico, from which over 90 per cent of world native-sulphur production is obtained; in sedimentary deposits such as those in Sicily, which are thought by some authorities to contain the largest world reserves of elemental sulphur; and as surface deposits, associated now or in the past with some phase of vulcanism, the type which bas the greatest world-wide distribution.Deposits of the volcanic type are the subject of this paper.From antiquity until the successful development of the sulphur-bearing salt domes at the beginning of this century, important sulphur production for local needs was obtained from volcanic deposits in many parts of the world. Due to technical and economic factors, however, producers could not compete in price with sulphur from salt domes. •The result has been that, except in Japan and Chile, little sulphur was produced from volcanic deposits from about 1910 until the start of the Korean war in 1950. Shortly after the outbreak of the Korean war, an acute world sulphur shortage developed and prices skyrocketed in many countries up to several hundred dollars a ton. Interest in volcanic deposits was renewed and exploitation of many was undertaken. Few of these operations have been successful, mostly due to inability of management to solve technical problems.While important volcanic deposits of elemental sulphur have not been reported ( 1) in Canada, and it is doubtful that any will be found, data presented in this paper may be of interest to students of ore genesis.This paper is based on field examination of numerous deposits of the volcanic type in North and South America."

Jan 1, 1954

By H. L. Cameron

Introduction Since the beginning of gold mining in Nova Scotia in the year 1860, the biggest problem o the mine operators has been to find and follow the ore zones in the narrow quartz veins. It was early recognized that all veins were not gold bearing and that, in those that were, the commercial ore was confined to limited zones. A large number of geologists and mining engineers have been interested enough to give time and thought to the problem, but, until the last four or five years preceding World War II, they were handicapped by lack of exact data from mining operations. The necessary data could only be obtained by daily checking of underground operations. Such daily checks were instituted at a number of mines during the period 1935-40 and, in every case, were successful in delimiting the ore zone or zones for the particular mine. The present paper deals with the results of this work as applied to practical ore finding. It is an attempt at extrapolation, from observations in the four districts with which the writer is personally familiar, co other districts in which similar conditions or structures are reported.

Jan 1, 1947

By R. C. Tait

The gold at Giant Yellowknife is intimately associated with a complex mixture of sulphides, including pyrite, arsenopyrite, stibnite, and a wide variety of antimony sulpho-salts. Direct cyanidation has never been feasible. Recovery is almost entirely dependent upon flotation, roasting of flotation concentrate, and cyanidation of calcine. In November 1958, an Edwards-type roaster and an early prototype, two stage Fluosolids roaster, were replaced by a large two-stage Fluosolids roaster of improved design. The new roaster was started at "safe" medium temperatures, but early in 1959, temperatures in both stages were gradually and deliberately lowered to determine whether continuous autogenous roasting could be maintained under exacting low temperature conditions necessary for good extraction. Operation is smooth and continuous with first and second stage temperatures controlled at 925° and 875°F respectively. Plant cyanide ex-traction compares very favourably with extraction from low

Jan 1, 1961