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This growing dependence of Canada upon foreign mineral commodities, just referred to, applies particularly in the direction of the United States. There is, in fact, no more significant feature of Canada's mineral trade than the manner in which it affects the Dominion's commercial standing with that country. Our heavy adverse balance of trade with the United States is perhaps not a matter of such wide concern or frequent comment as was the case two or three years ago. It is, of course, a well-known fact that the Dominion each year buys from the States a volume of goods to a value enormously in excess of our sales to that country. And it has come to be accepted as a ?normal, though not altogether satisfactory, feature of our international commerce that a huge portion of the bill incurred by our American purchases must be met, not by our American sales, but by the proceeds of our sales to other countries, not-ably Great Britain. It is a three-cornered situation in which our trading deficit with the United States is covered largely by our trading surplus with the United Kingdom. In this situation the mineral trade plays a remarkable part. If one delves into the details of our transactions with the United States it will be found that, in one sense, the mineral trade is entirely responsible for the huge annual balance against the Dominion. In fact, Canada gets decidedly better than an even break on Canadian American trade, if one leaves out of account the three mineral groups, "iron and steel", "non- metallic minerals", and "non-ferrous metals".

Jan 1, 1924

By D. Beneteau

Plotting sets of data collected over time using a frequency-magnitude distribution is common with both earthquake and mining seismology. A Time-Between-Events (TBE) analysis technique simply makes use of the inter-event times and b-values (slopes of the best fit lines on the frequency-magnitude charts) from the same set of data. Four distinct patterns in TBE versus Event Magnitude have been found which suggest whether there are constant seismic sources causing populations of data, or if the smaller and larger events, within the population represent varying seismic sources. Different rates of events, identified as TBE-rates in this study, may suggest whether the events are blast induced, or not. This study was done using actual seismic datasets from hardrock mines in Canada and Australia. This was to verify the applicability of the method to multiple mining environments and to determine the practicality and implications of this methodology to enhance the interpretation of seismic source mechanisms The results of the TBE technique and other proven techniques are combined into a Seismic Mechanism Assessment Worksheet. This is a tool that allows operators to compare trends within seismic datasets with assessments of in-situ rock conditions. The goal is to enhance the understanding of rockmass failure mechanisms.

Nov 1, 2011

By A. J. Smethurst, S. B. Hearn, S. Boskovic

"The problem of crud in solvent extraction is well known and can be a major handicap and operational issue. Colloidal silica can cause a number of problems including interfering with flocculation, initiating crud formation in solvent extraction (SX), decreasing SX extraction kinetics and increasing SX phase disengagement times. Flocculation can be utilized to remove some of the troublesome particulates but colloidal silica does not flocculate well and presents a different problem requiring innovative chemistry to solve. Coagulants can assist by facilitating the removal of this colloidal silica by promoting the agglomeration of the particles to a size which can be more readily settled or flocculated in solid/liquid separations. This is achieved when the coagulants bind to the surfaces, displacing water and destabilizing the colloids, whereupon they bind to each other which facilitate their amenability to conventional flocculation.INTRODUCTIONSilicate minerals are abundant in the upper layers of the Earth’s crust, and there are few mineral deposits without significant levels of gangue silicates. Silicate minerals include the pure silicas, such as quartz and other silicate containing minerals such as clays, chlorites, feldspars, as well a vast number of less common silicates.During the acid leaching of ores, two types of fine silica particles are released in solution from the dissolution of the host mineral. The first consists of partly depleted silicates, and the second is colloidal silica, which forms in solution. It is this second type which has the potential to cause crud formation as well as poor solution clarities, slow filter rates and excessive flocculant usage (Figure1)."

Jan 1, 2016

Training by Inclusiveness ?Background ?Video ?Results ?Partners ?How SEM works ?Future of SEM Background: Inclusivity partners ?Northwest Community College ?Smithers Exploration Group ?With support from the Province of BC ?Federal government ?And First Nations across the northwest

May 1, 2010

By J. W. Matousek

Since the late 1800s, copper-nickel ores have been mined and smelted in the Sudbury area. The Canadian Copper Company, the Copper Cliff ancestor of Inco Limited, commenced operations with a blast furnace smelter in 1888. Coal-fired reverberatory furnaces were added in 1911 and multihearth roasters in 1914. The blast and reverberatory furnaces smelted, respectively, coppernickel ores and ore fines until 1930, when a milling process and plant began operating to concentrate and separate the minerals of these two metals. Two reasons for this delay were: (1) the availability of high grade ores suitable for direct smelting; and (2) the difficulties in making the copper-nickel separation. The Mond Nickel Company, however, practiced flotation at its Coniston Smelter site from 1914 to 1930. A bulk concentrate containing six per cent copper and five per cent nickel was recovered from ore of 1.6 per cent each of copper and nickel. Gravity (table) and magnetic concentrates were also produced. Inco Limited (then The International Nickel Company) began laboratory-scale flotation tests on its ores in 1918. This work led, ultimately (in 1930), to the construction of the 7500 tonne-per-day Copper Cliff Mill, designed to recover separate copper and nickel concentrates. Its capacity was expanded to 11000 tpd in 1936, to 18 000 in 1940, and to 27 000 in 1942. Since 1971 it has operated to process only the bulk flotation products from other mills to yield individual nickel and copper concentrates.

Jan 1, 1999

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

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

Jan 1, 2016

By T. Crivits

"Phase equilibria in the ‘Cu2O’-‘Fe2O3’-SiO2 system, the base slag system in copper production, were recently determined. However, the addition of MgO, commonly present in the slag, drastically changes the phase equilibria in this system. The present study focuses on the phase equilibria in the ‘Cu2O’-‘Fe2O3’-MgO-SiO2 system in equilibrium with metallic copper.Recently, an experimental procedure has been developed that resolved a number of experimental difficulties. This procedure has been successfully applied to characterise several complex industrial copper slags. It includes a high-temperature equilibration followed by rapid quenching and electron probe X-ray micro-analysis (EPMA). The methodology was adapted to the present system and used to determine the liquidus at SiO2 saturation and in contact with high-MgO phases in between 1100 and 1250 °C in Cu2Orich slags.The results indicate a maximum solubility of MgO in the system at 1200 °C of 5 wt%. The boundary line between tridymite and spinel lies 3-4 wt% closer to the SiO2 apex for every 2 wt% MgO added. These new data on the high-copper slags are important for optimisation of the direct-to blister"

Jan 1, 2014

By B. R. Neufeld, M. G. Heximer, S. J. Roach, W. G. Van Luven, D. G. Reynolds

"Teck Metals Ltd. operates an integrated zinc-lead complex at Trail, British Columbia, Canada. In the zinc plant, zinc concentrates are roasted to produce calcine, which is then processed in the leaching circuit for zinc recovery. Calcine is first dissolved at pH <2.0. This is followed by a precipitation stage using additional calcine that removes iron as a ferric hydroxide precipitate which is recycled to the lead operations. It is during this pH adjustment that impurities, notably arsenic, antimony and germanium, are co-precipitated with ferric hydroxide which is the primary removal phase for these elements. Recent processing conditions have resulted in lower iron inputs to the leaching circuit and this has resulted in insufficient co-precipitation of key impurities. This paper summarizes the influence of iron concentrations on impurity removal using laboratory and plant scale surveys, and emphasizes key specification limits for the primary iron removal circuit.INTRODUCTIONThe Sulphide Leach Plant (SLP) at Teck Metals Ltd., Trail Operations produces a zinc sulphate electrolyte from three different zinc bearing streams:1. Calcine, primarily containing zinc oxide, from the roasters2. Zinc electrolyte from the Oxide Leach Plant (OLP) is produced by leaching zinc oxide fume from the pyrometallurgical lead smelting operations3. Zinc slurry from the Zinc Pressure Leach (ZPL) autoclaveThe feed sources are blended and introduced to the iron removal process to precipitate iron in the form of a hydrolyzed iron precipitate which is recycled to the lead smelting operation. Along with iron, impurities, namely arsenic, antimony, germanium and silica, also co-precipitate; this process acts as the primary removal step for these elements. Following iron removal, the electrolyte is further processed in the zinc dust purification circuits. Cadmium and copper are removed in the cold stage circuit via zinc dust cementation, followed by cobalt cementation in the hot stage circuit."

Jan 1, 2016

By The Staff

"SummaryDetermination of uranium in ores may be made by measurement of their radioactivity.The method most commonly used is that of measuring beta radiations with the tray-type beta counter. This will give an accurate uranium determination provided the sample does not contain thurium and that the beta and gamma activities have not been disturbed from their natural state of equilibrium. Such a loss of equilibrium will result from mining the ore or from the weathering of the surface rock.A method is described which eliminates errors due to loss of equilibrium. The beta and gamma activities are measured simultaneously in one simple operation. This method is recommended for assaying samples of products from milling operations and its use is limited only by the presence of thorium in a ratio greater than one part of thorium to twenty parts of uranium.A third method is recommended for the analysis of exploration samples and diamond drill cores, which may be assayed in the uncrushed state.Rapid determinations of a large number of samples is possible with the pressure ionization chamber, which is sensitive to gamma activity."

Jan 1, 1950

By Anne-Laure Bonnet

Les connaissances acquises au cours des dernières décennies sur les gîtes de métaux de base et précieux intensément métamorphisés (p. ex. Vokes, 1991; Cornell et al., 1992; Zaleski et Peterson, 1995) ont permis d?élaborer des guides d?exploration pour de tels gisements dans les terrains de haut-grade métamorphique (Spry et Scott, 1986; Rubin et al., 1993; Hand et al., 1994; Spry, 2000; Spry et al., 2000). Un transfert de ces connaissances à la cartographie des vastes terrains gneissiques non différentiés de la province de Grenville permet d?affiner l?approche cartographique nécessaire pour reconnaître les systèmes hydrothermaux métamorphisés en terrains vierges et peu diagnostiques puis d?en discriminer les divers halos d?altération (Corriveau et al.,1996, 1997, 1998, 2003; Williamson et al., ce volume). Cette approche prend en compte les « empreintes métamorphiques » observées sur le terrain, telles que les variations des assemblages minéralogiques, du mode et de la composition des minéraux métamorphiques, pour reconnaître des roches présentant une composition inhabituelle caractéristiques de protolites altérés par hydrothermalisme. Ces empreintes citées cidessus sont facilement reconnaissables dans les terrains de haut-grade où la recristallisation induit un grossissement des grains qui permet de déterminer la nature et le mode des minéraux dès les levés de terrain. Cette approche raffine la compréhension des terrains de haut-grade métamorphique et illustre que leur complexité (i.e. polyphasage de la déformation et du métamorphisme) n?est pas forcément une limite à leur exploration. Elle a donc été utilisée systématiquement lors des levés de terrain réalisés dans le cadre d?un projet de l?Initiative géoscientifique ciblée de RNCan. La zone cartographiée se situe le long de la marge sudest du Groupe de Wakeham dans le secteur est de la Province de Grenville. Deux régions ont été plus particulièrement étudiées, celle du lac Musquaro (SNRC 12K10, 11 et 14) et la région côtière comprise entre Kégashka, La Romaine et Baie des Loups (SNRC 12K1, 2, 3 et 7) (fig. 1).

May 1, 2003

By W. L. Bancroft, Peter Price

"What is now known as the 'Waite section' of the property of Waite Amulet Mines, Limited, was originally the Waite-Ackerman-Montgomery mine. It includes a group of twenty-eight claims lying on either side of the Duprat-Dufresnoy township line, and about 8 miles north-northwest of Noranda, Quebec. ,The original discovery of ore on the property was made by Thomas Montgomery in Block Q, Duprat township, and was staked by him on behalf of himself, I. C. Waite, and C. H. Ackerman, in the summer of 1925. The property was optioned late in 1925 to N. A. Timmins who, after trenching and drilling the deposit, sold his 85 per cent interest to Noranda Mines, Limited. Early in 1927, a company known as Waite-Ackerman-Montgomery Mines, Limited, was formed and shaft sinking and development undertaken. Production commenced in August, 1928, ·and continued tJ May, 1930, when, owing to falling metal prices, shipment of direct smelting ore was stopped. Development of the mine by shaft sinking, drifting, and drilling continued until March, 1932, when owing to the prolonged low price of metals, the property was closed down. In September, 1933, an amalgamation with Amulet Mines, Limited, was effected, the new company being called Waite Amulet Mines, Limited. Early in 1937 operations were resumed, first by direct shipments to the smelter and later by aerial tramway to the Amulet mill. Operations have been continuous up to the present time, reaching an average of 720 tons a day milled for the year 1940. Production during the initial period (1928-1930) amounted to 75,811 tons, having an average grade of 7 .11 per cent copper, 4.47 per cent zinc, and 0.03 oz. gold and 0.65 oz. silver per ton. During the second period (1937 to end of 1946) , 1,060,524 tons, having an average grade of 4.53 per cent copper, 2.97 per cent zinc, and 0.03 oz. gold and 0.65 oz. silver per ton, were produced."

Jan 1, 1954

By W. R. Richmond, T. S. Li, D. Ilievski

The reactive precipitation of ferrihydrite was studied in a laboratory semi-batch precipitator, where a highly concentrated sodium hydroxide solution was fed into an iron nitrate solution. Instantaneous hydrolysis of iron[III] takes place when the two reagents are mixed generating supersaturation, and leading to immediate precipitation of ferrihydrite via a primary nucleation mechanism then followed by limited crystallite growth to 3 to 7nm. A mathematical model of the semi-batch laboratory precipitator was used to simulate the pH responses during the precipitation of ferrihydrite at different reagent feed rates. The model comprised of interconnected compartments of averaged hydrodynamic conditions, incorporating physically meaningful turbulent mixing time constants. The precipitation process is described by the solute concentration conservation equation incorporating a postulated ferrihydrite primary nucleation model. It was found that the semi-batch precipitator model predicted the experimental pH response reasonably well. The experimental results demonstrated that the reagent feed rate has a critical effect on the course of the precipitation of ferrihydrite, i.e. it is a rate determining step given the fast hydrolysis and precipitation kinetics.

Jan 1, 2005

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

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

Jan 1, 1994

By C. Caballero, K. Itagaki, P. Morales, A. Moyano, J. Font

Codelco-Chile is considering different processing options for the new projected concentrate from the Alejandro Hales mine. This concentrate is featured by its high arsenic content of up to 6%. Thus, it is important for Codelco Norte Smelter to define the technical feasibility for processing this high-arsenic bearing concentrate in its main smelting unit as it is the Teniente Converter, which beside of its dual feeding system can enhance the arsenic removal by volatilization. The present paper which is a part of an extensive research work will focus in the performed industrial scale test for processing about 7,000 tonnes of a high-arsenic bearing concentrates in the Teniente Converter at the processing rate of about 2,300 tpd. The impact on the chemical quality of the produced high grade matte will be discussed, and the effect of the As removal by increasing the Teniente Converter processing rate of concentrates up to 3,000 tpd when producing 70% Cu in the white metal will also be addressed.

Jan 1, 2007

By A. Mukherjee, C. Kelly, B. Markovich, G. E. Agar, G. E. Robertson, F. Khan, B. Shea

"Laboratory batch flotation tests were performed on a sample of bulk slow cooled converter matte (Cu:Ni = I) to optimize the time in each of the separation stages. Numerical simulations were carried out to estimate a continuous circuit material balance for the conditions selected. An experimental simulation of a continuous circuit (locked cycle test) readily came to steady state and there was reasonable agreement between the numerical and experimental results. The use of nitrogen as the flotation gas and the addition of collector to the grinding mill minimized the oxidation of chalcocite, which has previously resulted in increasing circulating loads, and led to a stable circuit with very low weights in the recycle streams.IntroductionINCO Limited developed a flotation process for separating the components of copper-nickel matte [Sproule, Harcourt and Rose 1945; Sproule, Harcourt and Renzoni 1960] in 1945 to replace the Orford process and continues to use the flotation process in almost the original mode to this day. Initially the matte processed was the result of smelting a nickel concentrate that analyzed about 12% nickel and 2% copper and all of the recycle material that was generated in the smelting process. The matte generated analyzed about 25% copper and 53% nickel, roughly 2: 1 nickel to copper. This matte was blown in Pierce-Smith converters to be sulfur deficient in order to produce a metallic phase that collected the precious metals contained in the smelter feed [Wilson and Stratton-Crawley 1991]. This process continued with little change until 1994 when the separation of chalcopyrite from pentlandite in the Copper Cliff mill was discontinued after 63 years of operation. As a consequence of the elimination of the primary separation of chalcopyrite from pentlandite in the milling process a bulk concentrate was produced for smelting. Bulk concentrate smelting came into practice in 1994 as part of the initiative to meet government legislation that restricted the emission of sulfur dioxide to the atmosphere. Previously, the copper concentrate was smelted in an INCO oxygen flash furnace which resulted in the capture of a high strength sulfur dioxide stream from which liquid sulfur dioxide was produced. Nickel concentrate was smelted in reverberatory furnaces that produced low strength sulfur dioxide gases which were difficult to treat. The action taken by INCO to meet the environmental constraints was to smelt a bulk concentrate in oxygen flash furnaces which would produce gases suitable for the production of liquid sulfur dioxide and another stream that was high enough in sulfur dioxide to be readily converted to sulfuric acid [Bell et al 1990]. The end result of this decision was that all the copper-nickel separation would be done in the matte separation plant."

Jan 1, 1996

By M. Silver, R. H. McCorkell

The effects of covering materials on radon emanations from uranium mine mill tailings were investigated. Granular materials with air in the spaces allow radon to pass freely. Moist covers of compost or soil decrease radon emanation from tailings. Water-saturated covers were more effective, and freezing the tailings with these covers further decreased radon escape. Water itself is a poor radon barrier probably due to circulation. Plants had no effect on radon emanation through soil. Although radon diffusion through water-saturated powders appears to be very slow and inefficient, about 25% of the radon escaping from the grains in water-saturated tailings diffuse to the surface and emanate when no cover is present. The radon escaping from tailings through covers of water-saturated compost or soil is no more than could be accounted for by radon produced in the covers themselves.

Jan 1, 1987

By I. Imris

The chemical industries are using different type of catalysts, which after application usually produced many tons heap of residues. One of them is cupric oxide catalyst with high content of copper and silica. The recovery of copper from the waste has become major interest from a viewpoint of environmental protection and recycling of resources. The thermodynamic analysis and experimental results suggest that the copper from cupric oxide catalyst can be extracted by plasma reduction process. By plasma reduction process the inert slag and copper with following chemical composition: 99.04 % Cu, 0,042 % Fe could be obtained.

Jan 1, 2007

By Trygve Høy

"Important stratabound lead-zinc deposits in southeastern B. C. occur in rocks that range in age from Proterozoic Helikian to Middle Cambrian. The Sullivan deposit, and similar but smaller deposits in the Sullivan area are the only important deposits that occur in clastic rocks with little carbonate content. The highly deformed and metamorphosed Shuswap deposits, of probable Hadrynian to Helikian age, are in mixed marble, calc-silicate gneiss and pelitic schist assemblages, rocks transitional between clastics and carbonates. Deposits in younger rocks, such as the Kootenay Arc deposits in the Lower Cambrian Badshot-Reeves Formation and the Monarch -Kicking Horse deposits in Middle Cambrian dolomite, are hosted by platformal carbonate rocks.An important regional control for the distribution of deposits appears to be a northeast-trending tectonic zone that crosses the Rocky Mountains and the Purcell Mountains just south of the Sullivan area, and projects southwestward toward the Salmo camp at the southern end of the Kootenay Arc. Pronounced northeast-trending gravity and magnetic anomalies, basic volcanism of Hadrynian age (the Irene volcanics west of Creston) and a preferred alignment of Mesozoic granitic rocks indicates that the zone coincides with deep crustal structures. Within the zone are dramatic and abrupt thickness and facies changes in Hadrynian Windermere rocks and lower Paleozoic rocks, and on the east side of the Rocky Mountain Trench in Helikian Purcell Supergroup rocks, indicating that block-faulting was active intermittently within the zone from Helikian through to lower Paleozoic time. Right-lateral and reverse movements occurred on northeast-trending tear faults within the zone in Mesozoic time."

Jan 1, 1982

By V. F. Hollister

Four conditions are commonly accepted as being needed for the development of native sulphur deposits in sedimentary rocks : (1) ample sulphate-bearing evaporite, normally anhydritic; (2) proximity to petroleum deposits; (3) a hydrodynamic system of communication between these two; (4) a stratigraphic or structural trap to prevent escape of the sulphur and sulphur -bearing reaction products. When any of these requisites are absent, apparently no significant residual bio-epigenetic sulphur deposit will form. These requirements are, however, satisfied in some areas, which include both the Triassic and Devonian evaporites of northeastern British Columbia.

Jan 1, 1977

By James Mackie

The Vancouver Stock Exchange (VSE) has been providing venture capital for start-up companies since 1907. Ninety years' experience in the junior mining industry has enabled the VSE to develop policies and procedures tailored to the unique needs of start-up companies. Policies and procedures applicable to listed companies are documented in the Corporate Finance Services Department "Policy and Procedures Manual." Approximately 50% of the companies listed on the VSE are in the mineral exploration and development business. The largest number are exploring base metal, precious metal or diamond properties. A recent count shows that about 20 companies are exploring industrial mineral or non-metallic deposits. The minerals sought by these companies include limestone, decorative stone, building stone, lava rock, wollastonite, zeolite, garnet and graphite. There are two basic routes to obtaining VSE financing for an industrial mineral property. The owner can either sell an interest in the property to a listed company or form a company and have it listed on the VSE. In each instance, the listed company is responsible for raising funds to develop the property. A typical financing consists of the sale of company securities byway ofeitherprivate placement or prospectus offering.

Jan 1, 2001