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By Frank Wright

"The Icon Sullivan Joint Venture ore deposit was discovered in June, 1965 by Messrs. Paul Benard, Bob Galipeau and Mac Watson working under the direction of Mr. Andrew J. Troop, as employees of the Icon syndicate. The deposit is located on the Waconichici River as the south end of Baie du Poste of Lake Mistassini, approximately 45 miles north of Chibougamau. Property acquisition and Winkie drilling was followed by a diamond drilling program to evaluate the deposit. Stripping of the open pit area connnenced in the late fall of 1966 and the first test sample of ore was shipped to Chibougamau in December of that year.Regular ore shipments to the mill of Merrill Island Mining Corporation Limited for concentration commenced May 25, 1967. Production to December 31, 1970 amounts to 42,960,000 pounds of pay copper.The ore is chalcopyrite in white quartz dolomite, and it contains a very small amount of precious metals. The quartz dolomite assumes a flat to gently dipping attitude and is associated with a graphitic argillite contact zone on both hanging and footwall sides, in dolomitic limestone rocks. There is practically no other sulphide present in the ore.During the summer of 1969 a series of pre-concentration tests were completed and a Wemco heavy media sink float plant was installed in late 1969 and early 1970. This pre-concentrator eliminates at least one third of the ore mined in the form of barren quartz dolomite prior to ore shipment by truck to the concentrator in Chibougamau."

Jan 1, 1971

By A. B. Irwin

"Discussion at MeetingDR. D. DERRY (Ventures Limited) referring to the diagram (Figure 15) which shows a transverse structure section across the Central Slocan area, asked what the assumed structure at depth was, remarking that dips are steeper and more uniform at depth and that the contortions with gently-dipping axial planes are at higher elevations. He wondered whether the section represented ,part of a very large fold with steeply-dipping axial plane.MR. J. D. LITTLE (Canadian Exploration, Limited) replied that E. B. Mayo (Kelowna Exploration Company) and others had considered that the entire section illustrated faces to the southwest and represents part of the lower limb of a great overturned •syncline which is concave toward the southwest.DR. R. DEWIT (Geological Survey) remarked that the photograph of a ripple mark (Figure 7) showed internal lamination conformable to the ripple mark and wondered if the structure was not due to slumping during consolidation, since the normal mode of formation of ripple mark would seem to preclude the possibility of such internal stratification.MR. LITTLE remarked that in his opinion such structures should not be depended upon alone with-out other confirmatory evidence of the direction of tops of beds."

Jan 1, 1952

By Xuanxue Mo, Zengqian Hou

"Yidun Island Arc in Sanjiang Region is one of the important Kuroko-type volcanogenic massive sulfide deposits (VMS) districts in southwestern China. Tectonically, the region is situated in the eastern portion of the Tethys orogenic belt, and is a late Triassic extensional island-arc. The island-arc underwent earlier arc construction, intra-arc rifting, later arc construction and backarc spreading during its evolution and formed a complete trench-are-basin system, i.e., the Ganzilitang suture zone, forearc basin, outer are, intra-arc rifting zone, inner arc and back-arc basin from east to west across the island-arc.Kuroko-type VMS deposits and occurrences discovered so far are limited to within the intra-arc rifting zone of the Yidun Island Arc and tend to occur in groups or clusters distributed in separate faultbound basins; e.g., Zengke, Gacun and Xiangcheng basins, in which submarine volcanic rocks, especially bimodal volcanic suites, were extensively developed. The VMS deposits formed in the waning stages of volcanic eruption in the late Triassic and are hosted in the uppermost section of acidic volcanic rocks (rhyolitic-dacitic) within a bimodal suite. The orebodies are associated with these host rocks: rhyolitic-dacitic pyroclastic rocks and exhalites and chemical sedimentary rocks.All VMS deposits in Sanjiang are of the Zn-Pb-Cu type. The architecture of the deposits is twofold, consisting of concordant lenses and layers of massive sulfides and an underlying discordant stockwork. All deposits show metal zoning. The hydrothermal alteration related to mineralization is strong and asymmetrical, and is found dominantly within the stockwork zone and host rocks surrounding the ores. There are two alteration patterns: (1) chloritization - sericitization - silicification from outer sides to core of the alteration pipe; and (2) silicification + sericitization - silicification + carbonate from the lower to upper part of the alteration pipe.The mineralization temperatures of ore-forming fluids vary in the range 200°C to 335°C. Thermal evolution of the fluids displays temperature profiles that first increase and then decrease with progression of mineralization processes. The majority of black-ore minerals (Groups I and informed during intensifying stages of hydrothermal activity, and the majority of semi-yellow-ore minerals (Group III) formed during a thermal maximum. There followed the formation of fine-grained black-ore minerals (Group IV), which interacted with barite layers during decreasing temperature phases.Oxygen and hydrogen isotope studies show that the sources of ore-forming fluids for the Kurokotype VMS deposits are two-fold: seawater and magmatic hydrothermal solutions, represented by the Kuroko deposits in Japan and Kuroko-type VMS deposits in Sanjiang, respectively. In the latter case the hydrothermal solutions reacted with host rocks and mixed with cold seawater percolating downward, and circulated through volcanic rocks resulting in development of alteration zones and formation of ore minerals in Kuroko-type VMS deposits."

Jan 1, 1993

Abstract: ?The paper will review the perspective of Scotia Capital on financing mines, mining projects and mining companies in today's world of major increases in commodity prices, increases in capital and operating costs, shifts in foreign exchange rates, and increasing scrutiny of mining's social license ?Focus on debt financing alternatives Key Assumptions: ?Assume financing a mining asset (i.e. not an exploration play) ?Exploration is generally financed with equity ?private placements or public offerings on an idea

May 1, 2006

By Christopher Sherman

The engineering properties of a geologic material are greatly affected by the presence of macropores. Previous research has demonstrated that the size, location, and proximity of macropores influences both the strength and stiffness of specimens. Knowledge of the distribution of macropores in a specimen prior to testing would be useful for a number of reasons. We are developing a non-destructive method called cross-specimen acoustic tomography (CSAT) currently to determine some (or all) of the macropore characteristics for a laboratory specimen. The CSAT method uses a set of piezoelectric sensors that generate and receive high frequency acoustic waves. We measure the travel times of the acoustic waves through a specimen and then use a commercially available tomography software package to invert the data. The inverted velocity model is then used to locate the voids within the specimen. Two dimensional (cross-sectional) results from plaster specimens containing large macropores of Styrofoam show the technique is promising and worthy of further development.

May 1, 2009

By S. Nakamura, K. Fujiwara, S. Hirosawa, S. Tsukamoto, Y. Koshino, Y. Aruga

"In this study, hardness test, differential scanning calorimetry(DSC)and transmission electron micros copy were carried out to investigate the age-hardening behavior of Al-Mg-Si alloy with a Mg+Si concentration of 1.5mass%, and a Mg/Si ratio of 1.0. Pre-aging treatment was conducted for the solution-treated and then water-quenched specimen at 100, 80, 60, 40, 20 (natural aging), 0 and -20°C for 20min or 5h, followed by artificial aging at 170°C for 20min. It was found that when pre-aging time is prolonged from 20min to 5h, the bake-hardening response is deteriorated irrespective of the pre-aging temperature. In particular, the specimens subjected to pre-aging at 20-40°C for 5 h hardly increased the hardness with the subsequent artificial aging. From the results of DSC measurement, it was suggested that as pre-aging temperature is lowered, the amount of solute clusters formed during pre-aging, i.e. Mg-Si clusters and Si-rich clusters, is decreased, but the ratio of Si-rich clusters is increased, resulting in the deteriorated bake-hardening response.INTRODUCTIONIn recent years, Al-Mg-Si alloys have been widely used forautomotive body panels due to their excellent characteristics such as high strength-to-weight ratio and good formability. Their strength is increased not only by artificial aging during paint-bake treatment; i.e. “bake-hardening”, but also when kept at room temperature(RT);i.e. “natural aging”, in association with the suppressed bake-hardening response. Such a “negative effect of two-step aging” has been a serious problem because Al-Mg-Si alloy coils are unavoidably maintained at RT in the manufacturing process of body panels; e.g. shipping and storage. However, it was reported that pre-aging above 70°C before the two-step aging can restore the bake-hardening response, and such an improvement is related to the formation of solute clusters(Sato, 2006; Abidet al., 2010; Takaki et al., 2014; Zandbergen et al., 2015). From the comprehensive analysis by three-dimensional atom probe (Aruga et al., 2014 and 2015), it is believed that Mg-Si clusters formed during pre-aging transform into the strengtheningß"" phase, whereas Si-rich clusters formed during pre-aging act as a detrimental precursor of ß""phase. In this study, it was aimed to investigate the effect of pre-aging conditions, especially pre-aging temperature and time, on the formation of solute clusters during pre-aging, in order to elucidate the mechanism of the age-hardening behavior of an Al-Mg-Si alloy."

Jan 1, 2018

By Wataru Inagaki, Kozo Kawano, Tetsuya Ando

Cu–Ni–P alloys are the typical precipitation-hardening material. Thus, Cu–Ni–P alloys is expected to apply alternative materials for heat-exchanger tubes. Therefore, it was investigated that the effect of the heat-treatment simulated brazing on mechanical properties of Cu–Ni–P alloy in this study. The hardness of specimen as heat-treatment simulated brazing after solution heat treated (sht) was shown approximately 105 HV. The peak hardness and tensile strength of the specimen as performed aged at 498 K for 43.2 ks following the heat-treatment simulated brazing achieved at approximately 140 HV and 260 MPa, respectively. From these results, it is expected the application to higher-strength tube for heat-exchanger after brazing in a furnace. INTRODUCTION Copper prices have increased dramatically with high in recent years. At the same time, manufacturing industries are required to reduce the environment load by reducing the wall thickness of the copper tubes used in heat exchangers. High-strength copper alloys are developed for reducing the wall thickness, while achieving high strength, of the copper tubes. Moreover, excellent workability and corrosive durability are also required by these copper tubes. Furthermore, the brazing, which are carried out at about 1050 K during the assembly process of heat exchangers, leads to grain growth and re-solving of additive elements. Nomura et al. achieved a tensile strength and Vickers hardness of approximately 260 MPa and 110 HV, respectively, after aging at 723 K for approximately 36 ks. Tamagawa et al. studied that the strength of Cu–Ni–P alloy rapidly increased at about 125 HV during the cooling process after the heat brazing due to the Ni2P precipitates sized 5–10 nm. Furthermore, Inagaki et al. achieved a Vickers hardness of approximately 130 HV by aging at 498 K for 10.8 ks. In the present study, we focused on the lowest aging temperature of 498 K in the previous study, and investigating the effect of heat-treatment simulated brazing on the mechanical properties of the Cu–0.93 mass%Ni–0.24 mass%P alloy.

Jan 1, 2019

By G. B. Bosworth, M. J. Lake, J. W. Hogg

The Quintette Coal operation in northeastern British Columbia has one of the world's largest Preparation Plants, with a design capacity of 6.5 million tonnes per year of clean coal.This paper will discuss several innovative aspects of the flowsheet and plant design with particular reference to the selection of process equipment, materials handling and control systems.The operations and maintenance experience during the first two years of production will be described and discussed in relation to the design objectives.

Jan 1, 1987

By B. McFadzean, J. Taguta

In order to recover minerals by flotation, the sub-processes of collector adsorption onto the valuable minerals followed by bubble-particle attachment should occur efficiently. This paper investigates both of these sub-processes for various thiol collectors and their mixtures onto base metal sulfide minerals. The aim of the work was to investigate whether there is a correlation between the strength of the collector interaction with the mineral and the subsequent bubble-particle attachment. The collector-mineral affinity was measured experimentally using an isothermal titration calorimeter in order to determine the molar enthalpy of adsorption for each collector-mineral system. The bubble-particle attachment was measured using a microflotation device which essentially determines the hydrophobicity of the mineral. Sodium ethyl xanthate (SEX) and sodium diethyl dithiocarbamate (DTC) and mixtures thereof were used as collectors with either single minerals or binary mixtures of pyrite and chalcopyrite, respectively. The adsorption enthalpies of the collectors were interpreted with reference to the chemical structure of the collector molecule and showed that the greater the positive inductive effect of the collector, which may be qualitatively related to their pKa, the greater their affinity for the mineral surface. In the microflotation studies, recoveries were strongly related to the alkyl chain length but there was no correlation between the enthalpies of adsorption and the flotation recoveries. When mixtures of collectors were used there was clear evidence of synergistic effects and in the case of DTC/xanthate mixtures it is possible that this synergism is related to a DTC promoted oxidation of xanthate to dixanthogen. When mixtures of pyrite and chalcopyrite were used the flotation recovery and enthalpy of adsorption of SEX onto the individual pyrite particles in the mixture increased substantially compared to the case of pyrite alone. Mechanisms are proposed to interpret these important observations.

Jan 1, 2016

By Ken McClure, Alex Day

Located North of Williams Lake British Columbia, Gibraltar Mine is the fourth largest open pit Copper mine in North America. Gibraltar commenced Copper concentrate production in 1972 with a mill throughput rate of 30,000 tons per day. A series of expansion projects, including installation of a second SAG mill with variable speed drives in 2013, has increased mill throughput to 85,000 tons per day. Over the past 24 months, Gibraltar Mine in partnership with Spartan Controls has executed several advanced process control programming projects culminating in the implementation of a Continuous Speed Controller (CSC) for the most recently installed SAG mill. This paper covers development and results for the SAG mill speed controller. INTRODUCTION In January 2016, the price of Copper fell below $2.00 USD per pound, the lowest price in 7 years. Gibraltar Mine faced a significant challenge; how to maximize profit in an environment where capital spending was not an option. An opportunity was quickly identified to improve performance through increased automation and advanced control of the grinding processes. Beginning in March 2016, Gibraltar Mine partnered with Spartan Controls to introduce Advanced Process Control (APC) to the grinding circuits. The collaboration between metallurgical and process control engineering disciplines proved to be effective for achieving gains in throughput, reliability and productivity for the mill process. The Gibraltar milling facilities include 2 grinding-flotation plants for concentration of chalcopyrite ore with throughput rates of 58,000 tons per day (Concentrator 1) and 38,000 tons per day (Concentrator 2). Each of the two concentrators has a 34’ diameter SAG mill powered by 2 GE 4800 kW synchronous electric motors. For SAG 1 (in concentrator 1), power is transmitted through 2 Eaton Airflex clutches. For SAG 2 (in concentrator 2), the motors are driven by 2 TMEIC Variable Frequency Drives (VFDs). All programming is done using DeltaV, which Gibraltar uses as its Distributed Control System (DCS) and Human Machine Interface (HMI).

Jan 1, 2019

By Xiaolin Cheng, A. J. Sinclair

"Norm calculation procedures originally designed principally for igneous rocks are very rigid in their application and, in general, do not utilize important alteration minerals. For instance, volatile components are essential constituents of many metasomatic rocks but either are not used or are not used effectively in determining normative minerals by the CIPW norm or Niggli-Barth norm procedures. Our approach to determining norms for metasomatic rocks allots all major, minor and volatile constituents to a set of standard normative minerals which are commonly observed as products of hydrothermal alteration. A useful procedure is to have a metasomatic norm approximate the mode as closely as possible. Petrographic information helps to provide the necessary mineralogical constraints. With the recognition of an immobile component and knowledge of sampling and analytical errors in lithogeo chemical data, it is possible to recast norms into amounts of alteration minerals relative to a given amount (100 grams) of parent rock. Combining these results with the calculations of absolute loss or gain of individual chemical constituents and considering errors (e) for an appropriate confidence level, an overall (net) material exchange equation can be presented as follows:<equation>where all items have extensive units (e.g., grams). The model includes the initial and final mineralogy of rocks (evident in the field) as well as gains and losses of specific elements. Only those constituents whose calculated losses and gains are significantly different from zero are retained in the above model, and only the normative minerals with abundances significantly different from zero are included in the model (equation). One advantage of the chemico-mineralogic model is that parent rock and product are modeled in mineralogical terms that are familiar to and easily usable by exploration geologists."

Jan 1, 1995

By Xiaolin Cheng, A. J. Sinclair

"Abstract - Norm calculation procedures originally designed principally for igneous rocks are very rigid in their application and, in general, do not utilize important alteration minerals. For instance, volatile components are essential constituents of many metasomatic rocks but either are not used or are not used effectively in determining normative minerals by the CIPW norm or Niggli-Barth norm procedures. Our approach to determining norms for metasomatic rocks allots all major, minor and volatile constituents to a set of standard normative minerals which are commonly observed as products of hydrothermal alteration. A useful procedure is to have a metasomatic norm approximate the mode as closely as possible. Petrographic information helps to provide the necessary mineralogical constraints. With the recognition of an immobile component and knowledge of sampling and analytical errors in lithogeochemical data, it is possible to recast norms into amounts of alteration minerals relative to a given amount (100 grams) of parent rock. Combining these results with the calculations of absolute loss or gain of individual chemical constituents and considering errors (e) for an appropriate confidence level, an overall (net) material exchange equation can be presented as follows:SMineralparent rock ± e + SConstituentgained from solution ± e= SMineralaltered rock ± e + SConstituentlost from wall-rock ± ewhere all items have extensive units (e.g., grams). The model includes the initial and final mineralogy of rocks (evident in the field) as well as gains and losses of specific elements. Only those constituents whose calculated losses and gains are significantly different from zero are retained in the above model, and only the normative minerals with abundances significantly different from zero are included in the model (equation). One advantage of the chemicomineralogic model is that parent rock and product are modeled in mineralogical terms that are familiar to and easily usable by exploration geologists."

Jan 1, 1995

By Graham A. Davis

The definition of sustainable development is often taken from the so-called ?Brundtland? report, requiring that activities of the current generation not detract from the potential welfare of future generations. Mining is often held up as unsustainable in this regard since the extracted resource is nonrenewable. Yet Brundtland?s definition of sustainable development also requires that the current generation address the disparity in welfare across the globe, a facet of Brundtland?s report that most have ignored. This paper examines the impact of mining on the welfare of the poor. It finds that poverty levels in the poorest mining and oil intensive economies are lower than expected given these economies? geographical location and level of income, and that extractive activities are therefore completely consistent with sustainable development.

May 1, 2004

By Noko S. Phala

The energetics of CO and CO2 hydrogenation to methanol were studied on a gold surface via periodic and cluster DFT calculations. CO hydrogenation appears to be much easier than CO2 hydrogenation on an Au(111) surface. The use of a cluster model does not seem to improve the energetics of CO2 hydrogenation. It is concluded that an active support (e.g. ZnO) will be required to increase the productivity of a gold surface towards synthesis gas conversion. The energetics of CO and H2 adsorption are improved on the cluster model compared to a slab model of an Au(111) surface, suggesting that nanosized gold particles may be beneficial in CO hydrogenation.

Oct 1, 2003

By D. T. Smith, S. J. Strohmayr

Originally developed as a step change in ultrafine grinding efficiency, the IsaMill™ has made inroads into conventional ball mill and tower mill mainstream grinding duties during the last 5 years - beginning with the Anglo Platinum mainstream grinding projects in South Africa. At the 2006 SAG Conference, plant testwork on the incorporation of IsaMill™ technology into the McArthur River (Northern Territory, Australia) Pb/Zn primary grinding circuit was reported. The IsaMill™ has now become an integral component of that circuit, treating up to 1mm top size feed and directly producing P80 45 µm rougher flotation feed. Two 1.1 MW IsaMills™ are now used in this duty contributing to a 27% increase in overall plant throughput and a reduction in rougher feed size distribution. In this paper, we report on the current state of development and performance of the IsaMill™ in the primary grinding duty at McArthur River and also consider future directions.

Jan 1, 2012

By A. Fawceit, B. C. Dyer

"The basis of the tomographic velocity imaging technique is briefly described and an application of the method to detect and image a cross-section through a chromite pod is presented. Using the chromite application as an example, the relative costs of tomographic data acquisition and processing are compared with those of diamond drilling to obtain similar resolution. A number of different tomographic survey configurations and the potential role of the method in surface and underground exploration are discussed.IntroductionThe technique of seismic tomography has been most widely applied in oil industry exploration, nuclear waste disposal, civil engineering site investigations and in the assessment of the condition of mass concrete structures. Although model studies had indicated that tomography would be a useful tool in mineral exploration, relatively few applications have been reported.Essentially the method relies on the determination of the speed with which sound travels through a region within a cross-section of the earth or large body. The speed of sound is determined by the physical characteristics of the medium through which it is passing. In geophysics the speed of sound is generally referred to as the seismic velocity. Due to variations in the formations of different rocks the seismic velocity will vary and so can be used to map geological boundaries"

Jan 1, 1994

By James Ransford Dankwah

High sulphur carbonaceous materials like petroleum coke and rubber tyre are unsuitable as reductants in ironmaking because part of the sulphur is transferred to the reduced metal. Globally, while large amounts of petroleum coke are produced annually from the industrial processing of crude oil, billions of end-of-life rubber tyres are held in landfills and stockpiles. This work therefore investigates the potential feasibility of utilising these high sulphur carbonaceous materials as reductants in ironmaking without transferring the sulphur into the reduced metal. Composite pellets of iron oxide containing end-of-life rubber tyre (RT), petroleum coke and blends of RT/petroleum coke and petroleum coke/high density polyethylene (HDPE) were heated under argon atmosphere in a horizontal tube furnace. Reduced pellets were analysed after 10 minutes of reduction for their sulphur content. The results showed that sulphur-free metallic iron can be successfully synthesized using RT and petroleum coke as reductants. The level of desulphurisation depends on the nature of blending of the carbonaceous materials.

Jan 1, 2014

By Ronald C. Schimmel

In 2006, the Corus IJmuiden pellet plant produced approximately 4.6 mln tonnes of pellets. Corus IJmuiden is about to increase its pig iron production to 6.4 mln tonne HM per annum. The burden of the Corus IJmuiden blast furnaces consists of approximately 50% high basicity sinter and 50% acid pellets, both produced in-house. To enable an increased iron production, the capacity of the pellet plant needs to be raised to 5.0 mln tonne per annum. The capacity is increased by modifications to the plant layout, which were implemented during the 2006 cold maintenance stop. In addition, the composition of the ore blends is optimised to gain productivity.

May 1, 2007

Overview of Presentation Why Enter Agreements with First Nations Making it Win-Win ?The Principles The Process Making the Process Work Resource Agmts Defined Resource Agreements are legally binding agreements between a resource company and the First Nation(s) whose Aboriginal or Treaty rights may be impacted by the activities of the proposed project

May 1, 2009

By Neri Roux, Ross Gilders, Yemi Oyediran, Leo Cheung

Quest Rare Minerals Ltd. is developing their Strange Lake B Zone REE deposit located in Northern Quebec. An extensive batch bench scale testing program was launched to investigate open circuit rougher flotation performance under different conditions. The objective of the flotation study was to demonstrate the effectiveness of rejecting gangue minerals to flotation tailings while concentrating rare earth elements as well as yttrium, zirconium, and niobium into a concentrate suitable for further hydrometallurgical processing. Mineralization of interest at Strange Lake occurs within peralkaline granite-hosted pegmatites and minor aplite. The REE and high field strength element (HFSE)-bearing phases are hosted primarily in pegmatites as relatively fine-grained phases or pseudomorphs. The gangue phases comprise of quartz, feldspar, amphibole, and pyroxene. Potential ore minerals comprise predominantly of kainosite, gerenite, gadolinite, zircon, pyrochlore, and gittinsite. These complex mineralogical characteristics increase the difficulty for processing and provide a challenge for choosing the correct reagent scheme in rougher flotation. Process options including reverse flotation to reject the gangue minerals and de-sliming prior to the direct rougher flotation were investigated. Optimization trials were conducted using various reagent regimes and under different flotation conditions. Encouraging results were found using a combination of collector reagents supplied by Cytec Canada Inc.

Jan 1, 2014