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Organization Place Date 1913 Mining and Metallurgical Society of America New York, N. Y. Jan. 8 American Institute of Electrical Engineers New York, N. Y. Jan. 11 American Society of Civil Engineers New York, N. Y. Jan. 22-25 American Society of Heating and Ventilating Engineers : New York, N. Y. Jan. 22-25 American Institute of Mining Engineers New York, N. Y. Feb. 18-21 National Society for Promotion of Industrial Educa- tion New York, N. Y. Feb.. American Institute of Architects Washington, D. C. April American Iron and Steel Institute New York, N. Y. May New York Electrical Society New York, N. Y. June National Association of Stationary Engineers Cincinnati, 0. Sept. American Chemical Society Cleveland, 0. Sept.

Jan 1, 1918

By C De-Vitry

"The large Yandi channel iron deposit (CID) is located in the north-west of Western Australia and is currently mined via open pit methods. Drilling at Yandi is widely spaced and current estimates are mostly linear averages of the surrounding local samples. Linear estimates such as ordinary kriging (OK) based on block sizes that are significantly smaller than the dimensions of the drilling grid are less variable than the unknown reality (Armstrong and Champigny, 1989).Conditional simulation (CS) provides a series of plausible realisations that represent the actual grade variability at a small scale (eg 1 m + 1 m + 1 m). These simulations are very useful for a number of purposes, eg: optimising grade control, stockpiling and blending selection of optimal drill hole spacing assessing resource risk on contained tonnage and metal.At Yandi the major constituents of the ore (Fe, P2O5, SiO2, Al2O3 and LOI) are correlated to varying degrees. Independent CS of each assay variable will not reproduce these correlations. Reproducing the correlations (and the shape of scatterplots) is important if the simulations are used for the abovementioned purposes. This paper examines and compares various methods of CS that aim to reproduce the correlations between the assay variables.The CS methods evaluated in this paper are conditional co-simulation (CCS) using the linear model of co-regionalisation and two other, alternative multivariate simulation methods, which use min/max autocorrelation factors (MAF) or the stepwise conditional transform (SCT) to de-correlate assay variables before performing independent CS. It was found that CCS best reproduced the characteristics (histograms, variogram, scatterplots, etc) of the declustered drill hole data (Figure 1). Whilst simulation using MAF generally produced acceptable results, the method did not adequately reproduce the variance of the assay variables. The univariate statistics, histograms and experimental variograms were acceptable for simulations generated from the SCT. Bivariate statistics, cross-variograms and scatterplot reproduction for the SCT were unacceptable. The latter method produced inferior results because there were insufficient samples to obtain a reliable transform of the third assay variable in the transformation sequence.None of the abovementioned simulation methods provides good reproduction of all the scatterplots. This is due to the presence of clay pods, which cause some scatterplots to display two trends. These clay pods contain higher percentages of SiO2 and Al2O3 than the surrounding CID. The clay pods are generally smaller than the drill-grid dimensions. Thus their locations are typically unknown and they cannot be defined by manual interpretation, eg via wireframes. The locations of the clay pods were simulated via indicator CS. CCS was then performed separately for the clay pods and the CID. This significantly improved the reproduction of the correlation coefficients, the scatterplots and visually the simulation was more geologically realistic. Simulating the location of clay pods followed by CCS of assay variables is the recommended approach for simulation at the Yandi CID.CITATION:De-Vitry, C, 2013. Simulation of correlated assay variables - a case study from the Yandi Channel iron deposit, in Proceedings Iron Ore 2013, pp 137-148 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 12, 2013

By Joey Hoang, Robert Johansson, Tapani Keronen, Mikael Jåfs, Jani Jansson, Mikko Korpi

At the Copper 2016 conference in Kobe, Japan, Outotec introduced a vision for the year 2020, wherein smelting would make use of four digital cornerstones: intelligent instruments, advanced process control, improved information management and transparency of and access to data. Since then, this vision coined the phrase “Fully Automated Smelter” with the mission promising a concept where no manual actions from human operators would be needed during normal smelter operations. Replacing repetitive physical work, collection and analysis of everyday production data has a great potential for further automation and will provide productive ways to improve efficiency and safety of smelters in the future. Therefore, a lot of emphasis has been put into developing solutions to automate these tasks and to move people out of harm’s way. A lot of new equipment, systems and optimization tools are under development. In addition, a lot of effort is going into developing dynamic process models and advanced control systems to interface with the plant automation systems. The goal is to integrate all these concepts to meet Outotec’s Fully Automated Smelter vision. This paper will cover these latest achievements toward this vision and introduce the near-future of digital smelting. INTRODUCTION As is well known already, the humankind is currently experiencing a change, extent of which is broadly studied by the governmental, educational and industrial institutions and parties. The wellbeing and quality of life have traditionally been improved alongside the developments in industrial production, which is now about to enter its fourth revolution. Therefore, the current change is often described as fourth industrial revolution, or industry 4.0 (or industrie 4.0, as named by Acatech, 2013) and can be considered anything from small incremental development to a ground-breaking global reset that will affect everyone’s lives. Many seem to agree, that the scale of change will indeed be big, even significantly bigger than the three industrial revolutions before it (Pellini, Weyrauch, Malho & Carden, 2019; Geissbauer, Vedso & Schrauf, 2016; Jansson, Bjorklund, Lahtinen, Heinonen, Jafs & Fagerlund, 2016).

Jan 1, 2019

By E. Garay, J. P. Guzmám

A la fecha, el proyecto Magistral suma 344 Mt @ 0.45% Cu, 0.04% Mo en recursos totales (M+I+I) asociados a una mineralización tipo pórfido-skarn en el margen noreste de la Cordillera Blanca, Concuchos, en Perú. El depósito relacionase con un cuerpo intrusivo en rocas sedimentarias clásticas y carbonatadas del Cretácico. El intrusivo más importante es el stock Magistral, cuya composición varía de diorítica a monzonita y cuarzo monzonita, emplazado a lo largo de la Falla Magistral. Existen tres estilos principales de mineralización; tipo pórfido, tipo skarn y reemplazamiento de estratos (skarn distal). La edad de la alteración y mineralización ha sido determinada por los métodos K-Ar y Re-Os, correspondiendo ambas al Mioceno medio (15.3 ± 0.7 Ma en Biotita Hidrotermal y 14.73 ± 0.02 Ma en vetilla tipo “B” con cuarzo-feldespato potásico-calcopirita y molibdenita). Milpo sigue poniendo esfuerzos para hacer de este bonito depósito también un éxito minero.

May 1, 2008

By Douglas Beahm

Energy Metals Corp. (EMC) holds numerous mineral properties in the northern portion of the Great Divide Basin. The JAB property is one of several potential properties being planned for development as a satellite facility to the greater Antelope uranium project. A National Instrument 43-101 Technical Report was completed for the JAB property. This report estimated total measured and indicated mineral resources on the property totaling 1.6 kt (3,555,022 lbs) U3O8 contained in 2.2 Mt (2.4 million st) at an average grade of 0.073 percent U3O8 at a 0.25 grade times thickness (GT) cutoff in accordance with CIM Standards on Mineral Resources and Reserves. The JAB property is located in Sections 13, 14, 15, 16, 21, 22 and 23, Township 26 North, Range 94 West, approximately Latitude 42° 14’ North and Longitude 108° 00’ West (Fig. 1). This property consists of unpatented mining lode claims and Wyoming state mineral leases com-prising approximately 850 hm2 (2,100 acres).

Jan 1, 2007

Flue dust from the sintering of base metal sulphides was leached to remove cadmium and arsenic. Leach liquor contained cadmium, zinc and small amounts of other base metals as chlorides. Results are reported of the use of a cation exchange resin Zeocarb 225 to separate the base metals from the arsenic. The resin was eluted with sodium chloride or sulphate to give a solution of relatively concentrated cadmium suitable for recovery by zinc cementation. The limited solubility of sodium sulphate presented some practical problems which were investigated. Another problem was the precipitation of lead sulphate in the resin during elution.INTRODUCTIONWhen lead-zinc sulphides are sintered prior to smelting, the gases passing to the flue are mainly uncondensable but contain a certain proportion of sublimates and dust particles which deposit in the flue or are carried, after condensation in the gas stream, to some form of dust extraction equipment.The recovered dust is a complex mixture of base metal sulphates, sulphites, sulphides, chlorides and oxides, the composition depending on the original concentrates. A large proportion of the cadmium and some of the arsenic originally in the concentrates finds its way to this flue dust, the treatment of which can be a convenient means of removing these elements and controlling their concentrations in the main lead-zinc smelter circuit. However, disposing of this material represents an appreciable waste of base metals as well as a serious toxicity hazard.Sulphide Corporation Pty. Ltd. was faced with this problem in planning the flow sheet of the new lead-zinc smelter at Cockle Creek, N.S.W. From a test run carried out on a pilot plant at Avonmouth, U.K., using a mixture of lead and zinc concentrates, a sample of dust was obtained for...

Jan 1, 1960

"Desde 1950 en el Perú, el examen pre-ocupacional es un requisito para la inserción laboral dentro de la industria minera. Es por ello que la empresa se encargaba de la realización de la evaluación directamente. Posteriormente se designó dicha labor a un personal no facultativo, conllevando riesgos de salud futuros para el trabajador y por ende, a la producción de la empresa. En este sentido, el presente texto señala algunos de los aspectos de política preventiva de salubridad, donde sea el profesional médico, quien realice una promoción de salud y diagnóstico precoz de la enfermedad, protegiendo así la vitalidad del trabajador. Entre las principales funciones del personal médico a realizar tenemos: las contínuas visitas médicas al lugar del trabajador, desarrollar una permanente capacitación de actividades de higiene industrial, delimitar enfáticamente una orientación preventiva de su trabajo, etc. De otro lado, el trabajo muestra una descripción del formato médico (datos, historia ocupacional, antecedentes patológicos, sintomatología, examen clínico, inmunizaciones, clasificación de actitud) que debe considerar el examinador, para obtener un conocimiento conjunto del estado de salud del postulante y potencializar las capacidades del trabajador para la industria minera. De tal forma que se logra integrar en un solo documento médico, los resultados de los exámenes y se prescinde de la necesidad de contar con grandes archivos, facilitando el seguimiento de los casos."

Jul 20, 1957

By Joshua Hoffman, Braden Lusk, Kyle Perry

This study explores how different geometries affect the shock tunnel’s performance and is broken down into three phases. Phase 1: Open arena testing in which theoretical energies produced by the detonation of small (<1.0 kg) charges are compared to actual experimental values. Phase 2: Shock Tunnel testing in which realized energies are experimentally recorded for the UK and S&T shock tunnels. Phase 3: Analysis of the data to begin building a pressure-forecasting tool for the UK shock tunnel given the explosive characteristics, sample size and desired pressure and impulse.

Jan 1, 2009

By Adam Shang Robert Fu

The Yung-Chung-Tunnel in Taiwan, constructed for the Taiwan-East Railway Bureau, collapsed during construction when a water bearing, fractured marble zone was intersected. The inflow was approximately 4,000 liters/second. In spite of 30 relief holes the total inflow into the tunnel remained constant. The pre-excavation grouting through the re-aligned tunnel had to be conducted under extreme flow-conditions. A hot bitumen grouting program was selected for technical and economical reasons out of 13 international proposals. The technical challenges were: grouting under severe flow conditions high formation water pressures to be injected with hot bitumen at high temperatures and pressures The hot bitumen grouting program resulted in a dramatic reduction in the hydraulic conductivity and stabilization of the formation and facilitated a problem-free excavation.

Jan 1, 2007

By H. O. Hofman

WHEN dry chlorine gas is made to act in the cold upon finely¬divided gold,&apos; it converts the latter with evolution of heat into auro-auric chloride, Au2CI4, a hard, dark-red, hygroscopic salt. Moisture splits this salt into aurous and aerie chloride, Au2C14 = AuCI + AuCI3; treatment with water converts it into auric chloride and gold, 3 Au2CI4 = 4 AuC13 + Au,. Aurous chloride, when stirred with water, undergoes a similar decomposition, 3 AuCI = AuCI3 + Au,. These decompositions of auro-auric chloride and of aurous chloride furnish the explanation for the practice of moistening an ore before it is treated by the Plattner chlorination-process; practical experience having shown that gaseous chlorine gave an unsatisfactory extraction with dry ore. According to Rose,&apos; fine gold is acted upon more slowly by chlorine than gold containing some base metal, e.g., copper. He also states that small quantities of silver increase the rate of solution, but adds that the coating of silver chloride formed checks, and finally stops, further action, if the percentage of silver be increased beyond a certain undetermined amount. Bromine&apos; acts upon finely-divided gold in a manner similar to chlorine; the auro-auric bromide, Au2Br4, however, is not hygroscopic. Upon treatment with water it is decomposed as is the corresponding chlorine salt. It is generally believed that bromine does not act as energetically upon gold as does chlorine. This seems to be borne out by the results in the leach-

Mar 1, 1905

By Gustavo Quiquia Mucha

El presente texto describe las experiencias realizadas por la Compañía Minera Milpo SAA en el marco de una gestión social basada en la consulta previa, libre e informada en la Exploración Minera Responsable. En ese sentido, es importante la cooperación entre la empresa minera y la comunidad, así como la incorporación del marco ideológico empresarial y metodológico, basado en los principios del Convenio 169 de la OIT sobre Pueblos Indígenas y Tribales en Países Independientes, las estrategias y las líneas de intervención social de la Compañía Minera Milpo SAA en los proyectos de exploración minera responsable.

Sep 12, 2011

1. Domestic Production and Use: Twelve companies operated 31 primary aluminum reduction plants, three firms accounting for 66% of production. Washington, Oregon, and Montana accounted for 32% of the total production; Gulf Coast States, 25%; Northern States, 29%; and other Southern States, 14%. Output of primary metal in 1973 was valued at $2.2 billion. About 80% of the secondary recovery was from new aluminum base scrap and 20% was from old scrap. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1972, building accounted for 28%; transportation 19%; electrical, 13%; packaging, 16%; and consumer durab1es, 10%.

Jan 1, 1974

By M. Cohen, P. E. Beaubien, D. Caplan

Addition of 1 pct Mn to Fe-26 CY ca/(ses a12 increase in scaling rate at 870° and 1090°C. Whereas only the rhombohedral oxide, formrs on tire manganese-free alloy, with manganese present major amounts of the spinel .Mn0 . Pro-duced through which diffusion is more rapid. At 1090°C the scale formed OH Mn is highly, irregular due to blistering and sintering, This is a second cause of faster oxidation Since much of the blistered oxide does not participate as part of the protective layer. The oxide phases that form at different times depend on the degree to which the surface metal has become depleted, in manganese by preferential oxidation. PREVIOUS work has demonstrated that the oxide scales formed on chromium steels at high temperature consist of both spinel and rhombohedra1 phases and may contain considerably more manganese, especially in the spinel phase, than is present initially in the alloy.&apos; It has further been observed that a binary Fe-26 Cr alloy scaled less rapidly than an equivalent commercial steel and formed no spinel.&apos; However, it is not established if manganese in chromium alloys actually promotes formation of spinel nor if it affects oxidation resistance. It seemed expedient to try to evaluate the specific effect of manganese by oxidizing an Fe-26 Cr alloy containing a small manganese addition under the same experimental conditions as used for the manganese-free alloy.&apos; EXPERIMENTAL Table I shows the composition in weight percent of the Fe-26 Cr-1 Mn alloy and of the Fe-26 Cr alloy used as reference. The alloy with manganese was prepared from the vacuum-melted Fe-26 Cr alloy by remelting in vacuum with the proper manganese addition. The ingot was rolled to strip and specimens 1.1 by 0.035 by 5 cm and 1.1 by 0.5 by 4 cm cut out or machined. As previously described2 the specimens were smoothed by abrading through 600-grit Sic paper, electropolished in acetic-perchloric acid (20 to 1) to remove 10 p of metal, annealed at 1100°C in 20 torr of purified argon, and electropolished to remove a further 10 p of metal. They were then either rinsed in water and methanol and blotted dry or immediately etched for 45 sec in deoxy-genated 4 N HC1 under cathodic polarization at 10 pa per sq cm. Oxidation runs were carried out in a vertical tube furnace in a flow of purified oxygen at 1 atm while the weight increase was recorded continuously on a* automatic balance.3 Alter 98 hr at 870.C or 20 hr at 1090"C the specimens were removed to flowing argon and observed microscopically for evidence of spalling as they cooled. Subsequently they were examined by X-ray diffraction, the oxides analyzed chemically, and metallographic cross settions prepared. RESULTS Figs. 1 and 2 show the oxidation curves of Fe-26 Cr-1 Mn at 870&apos; and 1090C. The Fe-26 Cr reference runs are shown as dashed curves. Experimental details of the six runs are included in Table 11. The first 20 hr of run 1 is repeated in Fig. 2 to show the effect of temperature. At 8&apos;70°C the weight gain for Fe-Cr-Mn is about twice that of Fe-Cr (curve 1 vs curve 2, Fig. 1). Both alloys show regular oxidation curves. On parabolic coordinates (right-hand scale of Fig. 1) the

Jan 1, 1965

By S. L. Huang

The location and shape of potential failure surfaces in soil slopes were directly determined based on the stresses induced in the soil mass and the strength of the soil itself. Stress calculations were carried out by the finite element method with the Drucker-Prager nonlinear material model. The Mohr-Coulomb failure criterion and Mohr&apos;s circle stress analysis were then applied to the calculated stresses to determine the characteristics of the failure surface.

Jan 1, 1989

By Kym Runge, Emmy Manlapig

"The objective of an industrial flotation circuit is to separate valuable minerals from non-valuable minerals utilising differences in their flotation recovery rate. Regrinding and reagent addition are particle modification processes which are employed within these circuits to maximise the flotation selectivity of one mineral with respect to the others present in the ore feeding the process.Batch test nodal analysis, or the ability to compare floatability through mathematical combination of laboratory batch flotation test results, is a powerful technique for assessing the effectiveness of particle modification processes on ore floatability in industrial flotation circuits.In this paper, the use of nodal analysis is demonstrated within an industrial flotation circuit. It is used to show that regrinding and staged reagent addition within Teck Cominco’s Red Dog zinc retreatment circuit is beneficial to pulp flotation selectivity. Optimisation of these processes could potentially improve the zinc recovery within the circuit. Lime addition, which is periodically employed to depress pyrite in the circuit, was found to depress sphalerite in preference to pyrite and to result in poorer metallurgical performance in the circuit.INTRODUCTIONThe objective of an industrial flotation circuit is to separate valuable minerals from non-valuable minerals utilising differences in their flotation recovery rate.Different minerals can only be effectively separated using flotation if they are sufficiently liberated from each other (i.e. do not co-exist within the same particles) and have a sufficient difference in surface hydrophobicity. Size reduction processes and chemical addition are utilised before and within a flotation circuit to achieve sufficient particle liberation and to maximise differences in mineral hydrophobicity. In effect, the objective of these processes is to maximise the flotation selectivity of one mineral with respect to the others present in the ore feeding the process."

Jan 1, 2004

By J Law, S Jahanshahi, R Holmes

Iron ore is AustraliaÆs largest commodity export and is vitally important to AustraliaÆs current and future prosperity. However, while major expansions are currently in progress to satisfy demand, the industry is also undergoing major transformations. Reserves of traditional high-grade Brockman ores that have underpinned the Australian iron ore industry since its inception are slowly being depleted and alternative ore types such as Marra Mamba bedded iron deposits, Yandi and Pannawonica channel iron deposits and magnetite deposits are now being developed. However, the impurity levels in some of these alternative ores are higher and they require blending and/or upgrading as well as an advanced knowledge of their downstream processing characteristics to facilitate cost-effective utilisation by overseas customers. The research challenge is to use advanced techniques for mineral exploration, ore characterisation, mineral beneficiation, agglomeration and sustainable processing to identify and develop innovative and breakthrough options for locating, unlocking and enhancing the value of AustraliaÆs iron ore resources. Furthermore, to sustain the steel industry and hence secure the demand for iron ore, there is a growing need to enhance the environmental and business performance of the industry through reductions in wastes and emissions. Therefore, cost-effective breakthrough and enabling technologies that massively cut waste generation, CO2 emissions and water consumption are also being developed. These include the use of renewable fuels and reductants, waste heat recovery and conversion of by-product slag into a saleable substitute for Portland cement. A number of examples of recent developments in the above areas are provided in this paper.CITATION:Holmes, R, Jahanshahi, S and Law, J, 2013. Research and innovation for the iron ore to carbon steel value chain, in Proceedings Iron Ore 2013 , pp 3-6 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By Barbara Mazzini Loureiro

As placas de circuito impresso (PCI) são materiais heterogêneos e sua composição pode variar em função do ano de fabricação, tecnologia empregada, propósito de utilização, legislações vigentes e país de origem, entre outros. Essas características interferem diretamente no valor econômico agregado a estes resíduos, pois dependem da composição dos mesmos, de tal maneira que as empresas recicladoras tomam como base essas informações no momento da aquisição da sucata. Assim, a classificação e caracterização de PCIs é de suma importância para o mercado de reciclagem de resíduos eletroeletrônicos. A fim de alcançar este objetivo foi realizada cominuição em moinho de facas utilizando grelhas com abertura de 9, 6 e 3mm. A etapa de caracterização incluiu ensaios de digestão em água régia, perda ao fogo, análises química quantitativa por ICP-OES e MEV/EDS. Verificou-se que o lote de PCI estudado possui 39,5% de material cerâmico, 34,5% polimérico e 26 % metálico. A porcentagem em massa de cobre na placa é de 14,28%, de ferro 3,73%, de ouro 0,012% e de estanho 1,29%. O lote não é lead free e é multilayer com quatro camadas de cobre.

Aug 8, 2018

By L R. Marshall, M J. Rubenach, T G. Blenkinsop, J S. Cleverley

The source and transport regions of fluidised (transported) breccias outcrop in the Cloncurry Fe-oxide-Cu-Au district, providing insights into the origins of other fluidised magmatic-hydrothermal breccias such as kimberlites. Discordant dikes and pipes with rounded clasts of metasedimentary calc-silicate rocks and minor felsic and mafic intrusions extend several kilometres upwards and outwards from the contact aureole of the 1530 Ma Williams Batholith into overlying schists and amphibolites. The brecciation initiated at depths &gt;10 km and may have resulted in surface breaching. We used analytical equations for particle transport to estimate clast velocities (eÆ 20 ms-1), approaching volcanic ejecta rates (up to 80 ms-1). The wide range of CO2 fluid inclusion densities (up to 150 MPa), the localisation of the base of the breccias in contact aureoles, and the scale and discordancy of the bodies suggests the breccia transport process was triggered by an abrupt release of overpressured fluid. At these depths, such extreme behaviour may have been achieved by release of dissolved fluids from crystallising magma, in combination with a strongly fractured and fluid-laden source, sitting under a strong, low permeability barrier, and such parameters may be analogous to the asthenosphere/lithosphere boundary in the case of kimberlite initiation. The relationship of these breccias to the Ernest Henry iron-oxide-Cu-Au deposit suggests they may have been either fertile or æfailedÆ orebody feeders.

Jan 1, 2005

By Lane White

The 1989 Annual Meeting and Exhibit of SME in Las Vegas, NV, February 27 - March 2, 1989, was the largest ever, drawing more than 4000 regis¬trants and 240 exhibit booths. Technical sessions included presentation of nearly 500 papers, including symposia on Biotechnology in Minerals and Metals Processing, Surplus Capacity in the International Metals Industry, and APCOM `89 - the 21st International Symposium on Application of Computers and Operations Research in the Mineral Industry. Technical sessions covered the gamut of minerals industry interests; however, the proximity of the meeting to recently surging gold development in Nevada drew special attention to gold operating practices. Several of the papers on gold processing are reviewed below. To keep pace with the strong world- wide interest in gold development, SME has scheduled three additional upcoming programs that will focus specifically on gold: World Gold &apos;89 - Gold Forum on Technology and Practices will be held November 5 - 8, 1989 in Reno, NV, as a joint meeting and exhibit between SME and the Australasian Institute of Mining and Metallurgy. Technical sessions will encompass a full program of papers covering geology and exploration, mining, and mineral and metallurgical processing. Cooperating sponsors for this meeting include the Canadian Mineral Processors Division of CIM, The Institute of Metals, The Institution of Mining and Metallurgy, The Mining, Geological & Metallurgical Institute of India, and The South African Institute of Mining and Metallurgy. Gold &apos;90 - Salt Lake City, UT, February 26 - March 1, 1990, will be a symposium held in conjunction with the 1990 SME Annual Meeting. Current research on the processing of refractory gold ores will generate innovative papers on process mineralogy at this symposium, with special emphasis on gold with pyrite and gold with carbon. Other sessions are planned for gold exploration and mining, gold metallurgy, gold plant design and practice, and gold in scams. Advances in Gold and Silver Processing Conference, October 1 - 3, 1990 will be held in Reno, NV. Preliminary planning calls for technical sessions on heap leaching practice, refractory ore processing, non-traditional lixiviants, bioleaching, metal recovery from solution, and the environmental aspects of processing operations. PLANT DESIGN, OPERATION Technical sessions organized by the Minerals and Metallurgical Processing Division of SME at this year&apos;s meeting in Las Vegas covered a wide range of gold operating practices. Eight papers relating to gold plant design, operation, and equipment are summarized here. Preprints of these papers are available by writing to Publications Sales, PO Box 625002, Littleton, CO 80162-5002 ($2.50 per paper for AIME members, $4 for nonmembers). Continuous elution process A. M. Stone, of Bechtel Australia Pty. Ltd., described the "Development of the Continuous Elution Process for Extraction of Gold from Carbon" (pre-print 89-75). Developed by Bechtel Pacific Corp. for Ok Tedi Mining Ltd., the Continuous Elution Process uses the same reagents as batch processes for elution of gold from carbon, while yielding significant savings in stripping vessel size and energy consumed in comparison with equivalent batch processes. The process is also simpler to operate than batch processes. Other advantages include reduced maintenance costs, higher average eluate grade, and near steady final eluate grade. Pilot testing for the Continuous Elution Process was conducted at Western Mining&apos;s Kambalda gold plant beginning in December 1982. The Continuous Elution Process is a continuous countercurrent system operating in a pressure vessel at elevated

Jan 1, 1989

By H. R. Butler, J. F. Church, A. T. MacGibbon

Introduction Inco is the major North American nickel producer. Initially based in Sudbury, Ontario, its past exploration activity was directed toward finding new nickel deposits. New nickel sulfide discoveries outside Sudbury have included Thompson, Manitoba; Shebandowan, Ontario; and Widgiemooltha in Western Australia as well as a host of nickel laterite deposits. The company is currently diversifying into other commodities, including gold. Inco&apos;s exploration department participated in uranium discoveries in Saskatchewan and chromite discoveries at Tiebaghi in New Caledonia. In addition, it found new gold deposits at Lupin, Northwest Territories; Crixas, Brazil; Hoyle Township, Ontario; and Casa Berardi in Quebec. Crixas and Casa Berardi are currently being evaluated by underground exploration. Figure 1 shows some Canadian Shield gold locations where Inco is or was an active participant. Base metal developments Base metal exploration in shield areas has been greatly eased by applying scientific studies. Archean nickel sulfide deposits have been found using komatiitic-flow models (Fardon, 1971). Volcanogenic massive sulfide model has been applied to copper-zinc deposits (Sangster and Scott, 1976). Such deposits were subsequently seen developing on the sea floor through black smokers (Spiess, MacDonald, and Atwater, 1980). Sedimentary processes were recognized early as important in ore formation, particularly in the southern hemisphere (King, 1976). And many ore deposits are now regarded as a simple part of the geological column (Stanton, 1960 and 1972). Petrographic work on alteration patterns in and around ore bodies was used to develop standard porphyry copper models (Lowell and Guilbert, 1970). Epithermal models for precious metals followed. Stratigraphic zonation patterns have been formulated for base metal deposits, including keel facies, ore facies, and cap or distal facies. Gold developments The work on base metal deposits naturally spilled over into precious metal exploration when the gold price was allowed to float on world money markets. Early work on elements associated with gold deposits, especially arsenic, tellurium, selenium, and mercury, pioneered more detailed geochemical work (Bagby and Berger, 1985; and Groves, Ho, and Houstoun, 1984). Geochemical patterns have been recognized around microfine gold deposits. And the study of gold precipitation patterns in modern geothermal systems has helped understand gold deposition. In the late 1960s and early 1970s, it was noticed that numerous Archean banded iron formations contained anomalous gold values. From this and other observations, the syngenetic exhalite gold model has developed. Gold deposits also occur along shears in some plutons such as the Belmoral mine in Quebec. This indicates the importance of epigenetic processes in ore formation. Shield ore settings Initial studies recognized that the major gold camps in the Canadian Shield were mostly in greenstone belts and found along "breaks," especially zones of faulting and sedimentation. Gill (1948) wrote, "Only recently, as a result of detailed mapping, has the importance of major schist zones such as the Larder Lake, Cadillac, Porcupine Creek, and Destor Breaks been recognized. These zones of persistent adjustment mark broad belts favorable for ore occurrence." The importance of shearing in ore location and regional greenstone stratigraphic position close to late sedimentary packages was clearly understood. And structural models have been further developed for some Canadian ore deposits (Hubert, Trudel, and Gelinas, 1984). In the Beardmore-Geraldton camp of northwest Ontario, the importance was soon recognized of fold noses in banded iron formation, as localizers for gold ore. This importance had also been recognized in Western Australia,

Jan 2, 1987