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By E. M. De Souza, J. F. Archibald

This paper examines aspects of Canadian mine backfilling operations that may be implemented to assist in reducing solid waste production, lowering energy costs, and restricting Greenhouse Gas emissions. Many Canadian underground mines use backfill to mitigate environmental effects associated with tailings disposal. Backfill production and disposal are energy intensive processes that require an average energy cost of 37.7 MJ/tonne of backfill to complete. Mine backfills, in engineering applications, also commonly make use of cement as a stabilizing agent. Cement requires an additional energy cost ranging between 4,637 and 6,600 MJ/tonne to produce. The large energy needs associated with mine backfilling and cement production operations create significant CO2 and Greenhouse Gas emissions. Approximately 1 tonne of CO2 and Greenhouse Gas is emitted for each tonne of Normal Portland Cement produced. For single mines producing 3,000 tonnes of backfill per day, considering both backfill and cement emission source terms, total emissions of CO2 ranging between 120.36 tonnes and 169.44 tonnes/day are anticipated. In Ontario, mining operations contribute 700,000 - 840,000 tonnes/year of CO2 and Greenhouse Gas emissions to satisfy backfill cement consumption needs alone. Potential reductions of cement in backfill would significantly reduce emission of these gases and lower their adverse environmental impacts. This paper identifies alternate, equally effective and lower cost binder agent strategies for cement in backfill that may lead to cement consumption reductions. Post-consumer glass represents one such potential alternative backfill binder. Over 950,000 tonnes of glass are disposed of annually in Canada, two-thirds of which exists in the form of easily recoverable glass packaging that is not currently recycled or reused. The partial replacement of cement by waste glass may address goals for reducing non-recyclable glass waste disposal; enhancing mine back filling operations; reducing total backfill energy costs; and ultimately reducing Greenhouse Gas emissions levels currently generated by the Canadian mining industry.

Jan 1, 2004

By Zhiqiang Wang

This paper mainly focuses on the method of ?three-zone? definition (a caving zone, a fissure zone and a curve subsidence zone) for full height cutting in a thick seam. Based on criteria of a caving zone and a water conducting zone, as well as existing research achievements, it is believed that there exists great error for calculation of height of the ?three-zone? area using cutting height and the coefficient of bulk increase. Dynamic factors should be considered, so, based on the theory of key rock strata and combining this with several other factors, such as mining area, this paper presents a new method to determine the overburden ?three-zone? definition. The results are as follows: (1) geometric models of a working face and key stratum are established through the rock displacement angle, with consideration of the influence of mining on the key stratum (the range of key stratum influenced by mining is enlarged as the mining area increases); (2) because there is always a cavity below the key stratum of the thick coal seam with full seam cutting, and the key stratum gradually fracture with face advancing, based on the geometric dimension of strata, the maximum fracturing interval expression has been presented, including the working face advancing range. This can theoretically lead to the location of the key stratum influenced by mining, and its stability before mining, helps to confirm which zone the key stratum and following-up strata belong to, using the criteria of sliding instability or deformation instability; (3) the new method of ?three-zone? definition which is based on the theory of key rock strata is first proposed for full height cutting in thick seam. Finally, combined with practical engineering, and comparing with field data, it is believed that the proposed method is more objective than existing methods.

Aug 1, 2013

By F. F. Roberto, E. Kirby, A. R. Marchbank

The application of biologically assisted methods for metal extraction in the mining industry has a long history, but development of modern techniques has been relatively slow. There is, however, a resurgence of interest in the industry with the recent development of methods to successfully treat base metals concentrates. Two major pilot plant programs for treatment of chalcopyrite concentrates have been initiated in the past year and results from one are beginning to be released. This paper provides an overview of methods that have been applied in the past, from the earliest deliberate applications of the technology, through the copper and uranium heap and dump leach applications, the more highly engineered agitated tank leach gold applications and the developments currently taking place in the industry.

Jan 1, 2003

By Ausenco Engineering Canada

"This paper demonstrates the selection of grinding circuit technology for a number of recent projects including discussion of the key drivers and the role of energy efficiency. Decreasing head grades combined with a strong and sustained increase in operating costs has forced miners to examine increased project size, increased equipment capacity and efficiency improvements in order to reduce their unit operating costs and improve overall project economics. Comminution energy consumption, safety and capital cost considerations play a critical role in the success of projects. This paper presents some key guidelines for a successful and cost effective comminution circuit design and includes a case study on three projects, outlining the issues and the drivers which led to the ultimate circuit selection and the critical role that energy efficiency played.INTRODUCTIONComminution circuits for minerals processing are selected based on their suitability and efficiency in reducing run-of-mine ore to the desired feed size for the downstream process. The input material (ore) properties and downstream process requirements are the key determinants and there are standard approaches for each circumstance.The minerals processing industry has been a fast adaptor of efficiency improvements based on increasing capacity of equipment (e.g. trucks, crushers, mills, pumps) but less successful in adapting radically new technologies that disrupt incumbent flowsheets or processes.The installed power of grinding mills has increased linearly over the past 25 years (Meka & Lane, 2010) and pumps and classification equipment have kept pace. The autogenous grinding (AG) and semiautogenous grinding (SAG) mills displaced stage crushing as a dominant method of coarse rock breakage in many applications causing crusher manufactures to increase the capacity of cone crushers to meet the competitive demand.Examples of new comminution technology in the 20th and 21st centuries are the development and adoption of cyclone classification in the 1940s (Newtech, 2016), AG milling in the late 1950s, vertical grinding mills in the 1980s, high pressure grinding rolls (HPGRs) also in the 1980s and ultrafine milling technology in the 1990s (Meka & Lane, 2010)."

Jan 1, 2016

By M. A. Creaney

"The Construction Group is responsible for the construction of all of Placer Dome’s major projects and contributes to the development of most major feasibility studies. This group includes an international collection of Placer Dome people who have built mines in Papua New Guinea, Australia, Chile, the United States and Canada. This paper outlines the changing role of the Construction Group from the early days of single projects to today, when several projects are in various phases from feasibility to construction. The projects’ total annual budgets have from time to time exceeded one billion dollars. IntroductionAs the competition increases globally between the major gold mining companies, the impetus continues to build mines at the lowest cost with the shortest construction schedule. Placer Dome has more than met that challenge by building mines around the world at a pace that was not contemplated 15 or 20 years ago. Since 1960, Placer Dome has built 30 mines and expansions at a cost of nearly 4.5 billion dollars.In the last six years alone, Placer Dome has built 14 mines and expansions, worth 2.6 billion dollars. The company’s success is due primarily to Experience, Innovation, People and Standards.The diversity between projects, let alone the pace, has been a challenge. Placer Dome has built mines around the world in a variety of extreme climates and distinctive cultures. The construction experience gained from these projects has allowed Placer Dome to develop an extensive knowledge and data base making it easier to “fast track” projects.Through the years Placer Dome has developed a human resource base. It now has an experienced and adaptable core team of people able to set up construction projects and build mines anywhere in the world. By developing standards and systems to support the projects they can act as soon as a new project is approved, and complete the projects quickly and effectively. The result is that Placer Dome now has the construction expertise to build its own mines, giving them the competitive advantage that allows them to design and construct a mine in the least time at the lowest capital cost. This was demonstrated in March 1997 with the completion of the construction of two new mines in 12 months."

Jan 1, 1998

By H. Golzarpoor

Life Cycle Analysis (LCA) is a methodology for evaluating the environmental impacts associated with a product during its life cycle. LCA is identified as the most reliable method for verifying environmental impacts; however, current LCA-based approaches have certain limitations for environmental analysis of construction products. Integration of the LCA methodology with Discrete Event Simulation (DES) provides a sound framework for modeling and analysing the environmental impacts of construction products. LCA and DES is one possible combination for analysing the cause and effect of various scenarios where time, resources, and randomness of input variables affect the outcome and, therefore, has the potential to address the shortcomings of LCA in construction. Recent studies in disciplines other than construction such as manufacturing systems have revealed positive effects on evaluation of environmental metrics while integrating LCA with DES; however, this integration has not yet been applied for environmental analysis of construction products. By implementing LCA data in a DES model, this research proposes an environmental model of earthmoving operations in a case study. Environmental variables are simultaneously assessed with production variables in the same simulation model and the integration of DES and LCA is discussed.

Aug 1, 2013

By C. J. Brown

Since its commercialization thirty years ago, the Recoflo® short bed ion exchange process has been extensively utilized for the recovery of a wide variety of acids and metal salts. In addition to a reduction in resin bed height from 200 cm to 300 cm to 15 cm to 60 cm, the process has a number of features such as utilization of fine mesh resins in a compressed bed which together make it ideal for a number of applications. The process has been extensively exploited, for example, in the metal finishing industry for recovery of valuable chemicals from electroplating, anodizing, etching and pickling wastes. More recently, it has also been applied in the primary metals industry for purification of copper electrolytes and metals recovery from leachates. The paper discusses several of these applications and some of the issues that were found to be key to their success.

Jan 1, 2004

By L. Lariviere, M. Grenier, R. Khalili, D. Shook

A mineral processing facility near Montreal, CEZinc, Noranda Inc., has recently implemented a leading-edge intranet solution for monitoring the performance of plant operations, and providing condition-based maintenance. This innovative multi-faceted software implementation incorporates: web-delivered plant information systems; area-wide control loop performance assessment (using sophisticated algorithms to evaluate poorly performing controllers); and integrated alarm management functions.The system has enabled a project to improve plant operations through better process control. Maintenance technicians, engineers, supervisors and managers all can see the performance of the controllers, and the performance of the plant itself, through webdelivered graphics and reports. Information is combined from many sources, real-time, historical, relational and analytical, to provide a complete picture of plant operation.The web-based solution centralizes the administration of user access, and simplifies the deployment of several different kinds of information to many desktops. It is an extensible system that allows users to create and share their own web pages and data views.The paper will discuss the solution architecture and the improvements the IT, operations, maintenance, and engineering groups have experienced, and overall benefits to the facility.

Jan 1, 2003

By S. Shimaya, T. Maejima, M. Shimo

"The authors conducted the in-situ gas-tightness tests in a fractured rock at the Namikata underground LPG storage site in Ehime prefecture, Japan. The test consisted of two independent setups, a gas-tightness test that used boreholes, and a chamber-scale test that used a horizontal drift sealed with a concrete plug. In each test, the gas pressure was increased up to the onset of the measurable gas flow to obtain the maximum containment pressure. This paper discusses the hydraulic conditions for gas leakage initiation and the importance of the pore pressure measurement for monitoring the gas-tightness of the LPG storage cavern based on the test results.INTRODUCTIONJapanese first underground LPG storage plant was constructed by JOGMEC, the Japan Oil, Gas and Metals National Corporation, at Namikata in Ehime prefecture in granitic rocks (Kato et al., 2007). The “hydraulic sealing principle” (Åberg, 1977) that utilizes groundwater flow into an unlined cavern to prevent the leakage of gas through fractures in the surrounding rock mass was employed for storage of LPG. This paper describes the results of the in-situ tests performed at the Namikata Site to obtain information on fundamental gas-tightness characteristics of fractured rock. Two types of in-situ tests, a borehole gas-tightness test and a chamber gas-tightness test, were carried out near the storage caverns. Figure 1 shows the cavern layout of the Namikata underground storage plant and the test locations. The storage facilities consist of three caverns (W26m×H30m×L485m). The cavern crown lies at a depth of 150m below the sea level in Cretaceous granitic rock (Figure 1). Water curtain boreholes excavated from the water gallery tunnel at EL-125m level are located above and side of the caverns to prevent water drainage from fractures during the construction stage as well as during operation. The borehole tests were performed from a drilling adit excavated from the eastern end water gallery tunnel, while the chamber test was conducted at the southern edge of an exploratory drift extending from the central water gallery tunnel."

Jan 1, 2015

By W. H. Hannay

Introduction The subject matter of this paper will be treated under two heads: (1) experimental work and the development of the purification system, and (2) the operation of the commercial plant. During 1927-28, a two-ton slag-retreating plant was in operation at the smelter for experimental purposes. Details of this operation and of the commercial plant are presented in a paper by G. E. Murray, read before the Annual General Meeting of the Institute in April, 1933 (1). A point which has considerable bearing on the subject of the present paper, and which was not emphasized by Mr. Murray, is the concentration of volatile impurities in the zinc oxide fume produced. The result of the operation of the slag fuming furnace is largely to confine in a closed circuit all the minor constituents of the Sullivan concentrates, both lead and zinc. They pass into the feed of the zinc fuming furnace, with the result that all impurities which volatilize-such as arsenic, antimony, tin, fluorine, etc.-report in the zinc oxide product. The accompanying condensed flow-sheet (Figure 1) will illustrate this. The only outlet for impurities which is not shown is the small tonnage which passes the Cottrell plants. The flow-sheet would indicate the possibility of building up a prohibitive concentration of cathodic impurities in the oxide leaching plant feed. However, after three years' continuous operation this has not occurred. Should this condition arise at some future date, discard of some tonnage of blast furnace slag is indicated. In Mr. Murray's paper, the much greater flexibility of blast furnace operation, due to the slag fuming furnace, is stressed, particularly as to the lead content of the slag. The requirements of our lead refinery call for a bullion containing about 0.70 percent antimony.

Jan 1, 1934

"The Code was developed in 2004 through the Collaboration Agreement between Institution of Mining Engineers of Chile (IIMCh) and the Ministry of Mining (Chile) in Dec 2002. It is an amalgamation of current practices with respect to standards and procedures for exploration prospects, mineral resources, and reserves for the purpose of public reporting. Certification is required to prepare and issue information on mineral assets according to the guidelines that regulate the technical, economic, and environmental aspects that satisfy the conditions set by the Chilean capital and financial markets.The Mineral Resources Committee of the Instititution of Mining Engineers of Chile (IIMCh) is pleased to introduce theCode for the Certification of Exploration Prospects, Mineral Resources and Reserves which is the result of a Collaboration Agreement between the IIMCh and the Ministry of Mining established in December, 2002.This code synthetizes the present practice of the mining industry in regard to standards and procedures applied to exploration prospects, mineral resources, and reserves with the purpose of reporting publicly on financial instruments based on these mine assets in the capital markets. These standards follow general criteria already adopted and applied by capital markets in those countries characterized by a very dynamic and well developed mining sector such as Australia, Canada, Southafrica, United Kingdom, and others. The work done by the Mineral Resources Committee of the IIMCh has had the recognition of the Combined Reserves International Reporting Standards Committee (CRIRSCO) that leads the establishement of an international code in these matters. CRIRISCO is an entity formed by representatives of the countries previously mentioned, a representative of the Society of Mining Engineers of the UStates and a representative of the IIMCh. The Institution thanks the Ministry of Mining, the representatives of these Ministry in the Mineral Resources Committee, and specially the Minister of Mining, Sr. Alfonso Dulanto Rencoret due to the genuine support given to the IIMCh in the preparation of this Code.The Institution also thanks the Superintendencia de Valores y Seguros (SVS) because of the help given continuously to the Committee as well as by the interchange of opinions and suggestions received during the preparation of this document."

Jan 1, 2003

By S. Banisi, E. Arghavani, A. Akbari, Gh. A. Parsapour, S. Darvish Tafvizi

The new copper processing plant of the Sarcheshmeh copper complex consists of two parallel circuits. After a primary crushing, the ore is sent to a SAG mill and the product is further ground in a ball mill. The overflow of the hydrocyclones is fed to a flotation circuit which contains 8 rougher tank cells (RCS130), 3 cleaner cells (RCS50), 5 scavenger cells (RCS50) and a 4 x 12 m flotation column as recleaner. The circuit was initially designed to process a feed containing 0.8% Cu, but because of the ore type change, the feed grade decreased to 0.6% Cu. This resulted in a reduction of final concentrate grade and recovery from 28 and 85.5% to 24 and 84.4%, respectively. Based on the original design, the copper and silica recovery in the cleaner cells should be 69 and 55%, respectively, but these values increased to 85 and 75% because of a higher retention time. The rather high silica recovery (i.e., 75%) was found to be the main source of the lower final concentrate grade. In order to reduce the retention time of particles in the cleaner cell from 13.7 to 6.9 min, the rougher concentrates of two parallel circuits were fed to only one cleaner-scavenger and regrind circuit. This modification increased the cleaner and final concentrate grade from 15.1 and 24.5% to 17 and 26%, respectively. To prevent a possible reduction in the copper recovery, the froth depth in the scavenger cells was reduced. The overall outcome of the circuit modification was evaluated to be a 10% reduction in the energy consumption without any loss in the overall copper recovery.

Jan 1, 2016

By G. Armand, G. Arnold, A. Giraud, C. Auvray

The knowledge and understanding of the mechanical behavior of claystone is of critical importance in the aim of nuclear wastes storage. In this study, specimens of Callovo-Oxfordian claystone (COx) have been obtained from the ANDRA underground research laboratory in Meuse/Haute-Marne (France). This claystone is composed of carbonate inclusions (10-50µm) embedded in an argillaceous matrix (representing expanding clay minerals, such as smectites). The matrix itself is also multiphase and composed of clay aggregates of 1µm-size carbonate and quartz inclusions. This multiphase microstructure leads to a high heterogeneity witch was analysed through nanoindentation test grids. Moreover, the mechanical behavior of the claystone matrix is highly sensitive to humidity and temperature. The nanoindentation tests were performed in a climatic (i.e. temperature and humidity controlled) chamber at relative humidity levels from 50% to 98% and at two temperatures: 20°C and 60°C. In a first step, the curves of indentation were analysed using the commonly used Oliver and Pharr’s approach. Other wellknown parameters as the creep factor were also extracted. In a second step, Fisher-Cripps model (Fischer- Cripps, 2004) and Vandamme and Ulm model (Vandamme & Ulm, 2006) were used to identify viscoelastic properties. A statistical analysis is used in order to extract mechanical characteristics of the different phases. Hardness and elastic modulus decrease drastically with saturation (above 80% humidity) and to a lesser extend with temperature.

Jan 1, 2015

By W. B. Coker

A helicopter-mounted lake-sediment and lake-water survey was carried out over Grenville rooks in the Renfrew area (parts of Renfrew and Lanark counties) during four days of October, 1975. In the course of this survey. 1150 square kilometers were covered, with 246 lake-sediment and 276 lake -water samples collected from every body of water on which the helicopter could land. Sample sites, which averaged one per 4.6 square kilometers, included lakes, ponds, beaver ponds, swamps and marshes. Lake-sediment samples were taken using a G.S.C. sampler. Waters were collected directly into polyethylene bottles. At each sample site , surface and bottom-water pH, dissolved oxygen content, conductivity and temperature were measured using a Martel. Water Quality Analyzer. The lake sediments were air dried and then ball milled to pass a minus 80-mesh sieve. Lake sediments were analyzed for U by delayed neutron activation and for Mo, Cu, Zn, Pb, Fe, Mn, Ni and Co by atomic absorption techniques. The organic content of the sediments was determined by loss on ignition at 450 °C. Lake waters were acidified with nitric acid on the day of collection. The U content of the water s was determined by fluorometry; the Cu, Zn, Pb, Fe, Mn , Ni and Co contents of the waters were determined by solvent extraction - atomic absorption techniques. A close relationship was found between bodies of granitic, syenitic and pegmatitic bedrock and elevated U levels in the lake sediments. The Hurd Lake and White Lake granitic intrusive were encompassed by an annulus of higher U activity. Field inspection revealed that the U concentrations occur within a zone which may represent a contact metamorphic aureole. Within these complexes, anomalous concentrations of U appear to be associated with Mo. Information derived from the lake-water data reinforces the geochemical distributions outlined by the lake-sediment survey . This survey was carried out in order to develop optimum sampling and analytical procedures for geochemical reconnaissance of the Grenville Province that may be carried out under the auspices of the Uranium Reconnaissance Program.

Jan 1, 1977

By H. C. Gunning

Introduction The invitation to contribute a discussion on some of the broader features of the mineral deposits of our Cordillera seemed acceptable enough when presented several months ago. More mature consideration has impressed upon me the difficulty of making any constructive or very helpful contribution in the short time available and with my limited inspiration. Dr. Lang deserves our real gratitude for his general paper of nineteen pages at the beginning of the Volume. Into it, with the help of two diagrams and seven tabular summaries, he has packed a lot of useful information and has analyzed along several lines the data of the Volume's twenty-eight detailed papers on our mines and camps. He has added additional facts from his own knowledge of the region. I am sure that, like myself and the whole fraternity, he feels especially grateful to the eleven company geologists who found time to contribute detailed descriptions of mines they have studied. The Regional Situation With the Jubilee Volume and two recent publications of great value from the Geological Survey, we are more up-to-date on Cordilleran geology than we have ever been. But I would like to emphasize that we still have but fragmentary information. Brief study of G.S.C. Map 932A will illustrate this. Our knowledge of the Rocky mountains is limited to two narrow sections along the main railway lines, a somewhat larger area from the border north along the Mesozoic coal-bearing basins, and some reconnaissance along Peace river and the Alaska highway. There is some additional information on old maps, particularly those by G. M. Dawson, but it is very much of the 'exploratory' type. The other mapped areas are chiefly in the accessible region south of 'fifty-one', in the central part adjacent to and spreading north, recently, from the Canadian National railway, and along the edges of the Coast Range.

Jan 1, 1950

By R. J. Johnston

"INTRODUCTIONPoint Mines is located about 65 miles east of Hay River on the South Shore of the Great Slave Lake. It is connected to the Northern Alberta Railway System by the Great Slave Lake Division of CN Railways at Roma Junction, Alberta.The operation started in the fall of 1965 with a capacity of 5000 t.p.d. An addition was put into operation late in 1968 to bring the capacity up to 8000 t.p.d. The present milling rate is 11,000 t.p.d.The location of Pine Point Mines is such that long end cold winters are to be expected end temperatures of lower than -200F are encountered from late October to late March, with extended periods of -300F being common in January and February.It was recognized by Cominco engineers during the initial design period that since freezing would be encountered with open pit ore somewhere in the crushing circuit, the problem was to reduce it as much as possible. Other mines, working under similar conditions, found that the fine ore bins feeding the grinding circuit were the main problem area. The decision was reached, therefore, to have heated fine ore bins and to make sure thst the ore was sufficiently warm to prevent freezing.CRUSHING PLANT FLOWSHEETThe crushing plant has a standard open flow circuit (flowsheet). Ore from the stockpile is loaded into R-50 Euclid trucks by Caterpillar 992 Front End Loader with 11 cu. yd. bucket and dumped into a 42 x 65 C.A.C. Superior Crusher driven by a 300 HP motor. The crusher is set at a nominal 5 inches. The ore falls through into a 100-ton surge bin. There are high level and low level nuclear gauges to allow the primary operator to optimize for optimum orientation."

Jan 1, 1972

By Dale A. Sketchley

The objective of Quality Assurance and Quality Control programs on advanced exploration projects is to ensure that data from sampling, assaying, and recording of geological observations are of high integrity for the purpose of obtaining reliable mineral resource and reserve estimates. National Instrument 43-101 Standards of Disclosure for Mineral Projects states that all scientific and technical reports must be prepared and certified by a Qualified Person in accordance with professional and industry standards following Mineral Exploration Best Practices Guidelines and Definitions, and Guidelines of the CIM Standards on Mineral Resources and Reserves. Additional information is given in Companion Policy 43-101CP and Technical Report Form 43-101F1. Although the Qualified Person must discuss and describe the Sampling Method and Approach; Sample Preparation, Analyses, and Security; and Data Verification; there is little specific information in the guidelines on Quality Assurance and Quality Control programs. Examples from the Oyu Tolgoi Cu-Au Project are given for optimizing sampling protocols, following proper sample preparation procedures, safeguarding sample shipments through chain of custody, ensuring quality of assaying with Round Robin monitoring programs, verifying transcribed data, and validating data with check assays to ensure high integrity for resource and reserve estimation. Oyu Tolgoi, also known as Turquoise Hill, is in the South Gobi desert, Mongolia, about 550 km south of the capital city of Ulaanbaatar, and 875 km northwest of Beijing, China. The project covers a major copper-gold system, which consists of the South West, South, Central, and Far North deposits, comprising high sulphidation and porphyry mineralization with oxide, supergene, and hypogene ore types. Exploration is done by multiple diamond drill rigs, and samples are prepared on-site and shipped to laboratories in Mongolia, Canada, and Australia for further preparation and analysis.

May 1, 2003

By Trevor R. Ellis

"The valuation of mineral properties in the U.S. is only partially regulated. The regulations which have jurisdiction or impact appear to have such mainly as a consequence of unintended fallout, since the regulations were designed for other purposes. Court case history can also be important. The combined results are a mixture of bad and good, with important lessons to be learned.Since 1981, the Securities and Exchange Commission has prohibited U.S. listed companies from reporting quantitative estimates of mineralization and the value of mineralization, other than proven and probable reserves. This results in the minerals appraiser (valuator) working with a shortage of data in his everyday work, both on the subject property and in sales analysis.Between 1989 and 1995, all 50 states and essentially all Federal agencies adopted the Uniform Standards of Professional Appraisal Practice (USPAP) for real property appraisals (valuations). The major national appraisal societies also require their members to abide by USPAP. A significant portion of minerals appraisals must now follow these standards. This paper will discuss the content of USPAP. It provides a very good framework for the valuation of a minerals property or a mine, both as real property and as a business. However, the credentialing standards for real property appraisers are now prohibitive for minerals appraisers."

Jan 1, 2003

By Zhao-shu Sun, Mao-lin Li, Rui Cui

"Fankou Mine produced pyrite concentrate (PC) from the tailings by rougher and scavenger flotation before 2010, with the averaged S grade of 40.54% at recovery of 79.34%. The economic value of PC increases with its purity. When the S grade of PC feed to sulfuric acid plant is over 47%, the pyrite cinder can reach a high Fe grade of 62% which can be directly sold as iron concentrate. On this background, engineers in Fankou Mine set the PC with S grade of 47% as target.The direct way to reach that goal was to clean the rough PC Lots of cleaner flotation tests were conducted and the balanced strategy was to produce two ranks PC with the S grade of 47% and 38% at the recovery of 44.20% and 36.17%, respectively. The dual-product flowsheet was successfully industrialized in 2010. In order to further improve the quality of PC, gravity separation was introduced into the flowsheet. The numerical simulation and tests were performed to evaluate the beneficiation and classification performance of hydrocyclone as it treated the rough PC. It was shown that the underflow of hydrocyclone could addressed the S grade of 47%, and the finer size overflow could also be enriched to PC with S grade of 47% by flotation, due to the contained pyrite with well liberation. That is to say, with the ingenious addition of hydrocyclone to treat the rough PC, single PC with S grade of 47% could be achieved. The new flotation-gravity separation flowsheet was commissioned to produce the high quality PC at the end of 2013. The averaged S grade is 47.20% at recovery of 82.26% in 2014. The two steps flowsheet improvement maximizes the enterprise benefits and leads to simple utilization of Fe in pyrite in downstream industry."

Jan 1, 2016

By T. Koulomzine, R P. Jaeggin

The claims now held by Mount Wright Iron Mines Co. Limited were acquired by staking in 1956, 1957 and 1958, i.e., some time after the major deposits of the Quebec Cartier Mining and Normanvi!le Mining Co. (formerly Quebec Cobalt & Exploration Ltd.) were already discovered and partly outlined. The choice of the location of the Mount Wright hold-ings was governed simply by the -availability of ground still open to staking and by its proximity to properties held by major iron companies. Mount Wright Iron Mines had no previous knowledge of the geology and no aeromagnetic results were available to it to guide the choice of areas to be staked. In order to explore the newly ac-quired claims it was decided to make a grid of widely spaced magnetic profiles on the ground rather than use aeromagnetics. This afforded the possibility of making some geological observations simultaneously with the geophysical measurements.

Jan 1, 1961