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By N. A. Beier, R. Amos, Smith. L., C. Atherton, D. R. Barsi, D. Blowes, D. C. Sego

"Waste rock is one of the most abundant materials at mine sites and must be properly characterized and managed to limit acid rock drainage and other harmful byproducts. An experimental waste rock pile—part of the test piles research program—located at the Diavik diamond mine (Northwest Territories, Canada) was deconstructed and sampled to study the spatial variability of material properties. Bulk samples were classified based on the amount of material finer than 4.75 mm. Hydraulic properties of each sample were estimated and particle size distribution analysis was completed. These datasets and classification methods might be used to improve the understanding of hydraulic and geochemical behaviour of the material and to study waste rock at other sites. ¦ KEYWORDS Acid rock drainage (ARD), Material classification, Particle size distribution (PSD), Waste rock RÉSUMÉ Les stériles font partie des matériaux les plus abondants sur les sites miniers et, en tant que tels, doivent être correctement caractérisés et gérés afin de limiter le drainage rocheux acide (DRA) et la pré¬sence d’autres sous-produits nocifs. Dans le cadre du programme Test Piles Research Program, un amas de roches stériles expérimental situé à la mine de diamant Diavik (Territoires du Nord-Ouest, Canada) a été décomposé et mis à l’essai afin d’étudier la variabilité spatiale des propriétés des matériaux. Les échan¬tillons en vrac ont été classés en fonction de la quantité de matériaux plus fins que 4,75 mm. Les propriétés hydrauliques de chaque échantillon ont été estimées et l’analyse de la composition granulométrique effectuée. Ces ensembles de données et méthodes de classement serviront à mieux comprendre le com¬portement hydraulique et géochimique du matériau et à étudier les stériles sur d’autres sites. ¦ MOTS CLÉS classement des matériaux, composition granulométrique, drainage rocheux acide (DRA), stérilesINTRODUCTION Statement of problem The characterization of mine waste rock remains a challenge in active mining sites. The large volume of material and the large size of particles make it difficult to collect representative samples. Sampling techniques are often dis-ruptive to mining operations because they alter the structure of the waste rock pile or interfere with mine traffic. The convention at most mine sites to collect little to no information on waste rock material means that models and predictions of how waste material will behave and interact with the surrounding environment are based on general information that might not be site specific. This could lead to environmental damage or higher costs if environmental effects are underestimated during the construction of waste rock structures."

Jan 1, 2019

By C. J. Brown

Controlling the level of impurities in copper refinery electrolytes is essential to achieving acceptable cathode purity. Purge of electrolyte is not an entirely satisfactory solution since the cost of neutralization, waste disposal, and replacement acid can be appreciable. The APU® process utilizes ion exchange resin to sorb sulphuric acid while rejecting metal salt impurities. Extensively employed for recovery of waste pickling and anodizing acids since 1977, the system is now being used at several refineries for removal of contaminants such as antimony, bismuth, iron, and nickel. The purified acid, which is recovered from the resin by water elution, is recycled back to the refinery tank-house, while the metals are typically recovered from the de-acidified by-product solution by precipitation.

Jan 1, 2005

By P. R. Stephenson

Mining projects depend on the amount and quality of the mineral reserves, which in turn depend on the amount and quality of the mineral resources. Only Measured and Indicated Resources may be converted to mineral reserves and Inferred Resources may not, with certain exceptions, be used in economic studies. Responsibility for the estimation of mineral resources rests with the Qualified Person (QP) and there is a wealth of literature, text books and case studies to guide the QP. Responsibility for the classification of the mineral resources also rests with the QP. While there is some industry guidance and common practice on approaches to resource classification on which the QP can draw, the process is (or should be) heavily dependent on the exercise of judgement by the QP. However, this inevitably leads to situations where, for example, one QP?s Inferred Resource is another QP?s Indicated Resource. If the QP?s judgement is poorly reasoned or illogical (as is sometimes the case), it can have a major impact on the project, often with substantial cost or value implications. Project managers and company executives should not unquestioningly accept QP?s classification decisions and should apply the same intensity of due diligence that they apply to other critical elements of the project.

May 1, 2011

By I. Campbell, P. C. Jones, E. G. Potter, R. P. Taylor

"The Cobalt embayment is a large domain of Paleoproterozoic clastic sedimentary rocks that unconformably overlies the Archean Abitibi greenstone belt. Regionally extensive sills and dikes of Nipissing diabase, emplaced circa 2219 Ma, occur throughout the embayment and are the preferential host to gold-bearing polymetallic vein systems on the Merico-Ethel property, near the northeastern margin of the Cobalt embayment. These gold-bearing, polymetallic veins are predominantly east-west-trending, steeply dipping, discordant calcite- quartz vein systems that formed close to the time of crystallization (within ~15 m.y., based on Pb-Pb ages) of the Nipissing diabase. The ore mineralogy is complex in character, typically comprising sulfides, arsenides, native metals (gold and silver), and specular hematite, preferentially concentrated along the interface between silicate and calcite gangue. A simplified sequence of mineral deposition in the veins is: (1) "Early-stage" pyrite ± chalcopyrite hosted in quartz ± chlorite gangue; (2) "Main-stage" polymetallic (Cu + Co + As + Ag + Au + Bi ± Pb ± Ni ± U) sulfides, arsenides, and native metals hosted in calcite gangue; and (3) "Late-stage" calcite flooding ± galena. Wall-rock alteration in Nipissing diabase is restricted to narrow (<5 cm) haloes of calcite-chloriteepidote- bearing assemblages, whereas a weak alteration halo of specular hematite, calcite, and allanite-epidote has been observed in the surrounding sedimentary rocks. In terms of their age, geology, mineralogy, paragenesis, and morphology, the gold-bearing vein systems at Merico-Ethel closely resemble the silver-sulfarsenide vein deposits of the historic Cobalt and Gowganda mining camps. These observations indicate that the Au-bearing veins are variants of the Ag-vein systems and as such, have a common genesis belt. L’Échancrure de Cobalt est un large domaine de roches sédimentaires clastiques d’âge Paléoprotérozoïque qui reposent en discordance sur la ceinture de roches vertes d’Abitibi d’âge Archéen. La Diabase de Nipissing, mise en place vers 2219 Ma et qui constitue un réseau de sills et de dykes d’importance régionale, est présente dans l’ensemble de l’échancrure et constitue la roche-hôte principale des systèmes de veines aurifères-polymétalliques de la propriété Merico-Ethel, près de la bordure nord-est de l’Échancrure de Cobalt. Ces veines à minéralisation aurifère et polymétallique constituent un système de veines de calcite-quartz sécantes d’orientation principalement est-ouest et à pendage fort qui se sont formées peu de temps après la cristallisation de la Diabase de Nipissing (à ~15 Ma près, d’après les âges Pb-Pb). La minéralogie de la minéralisation est complexe; elle consiste typiquement en sulfures, en arséniures, en métaux natifs (or et argent) et en hématite spéculaire, préférentiellement concentrés à l’interface entre les silicates et la gangue de calcite. La séquence de déposition simplifiée des minéraux dans les veines est : (1) «Stade précoce» pyrite ± chalcopyrite encaissés dans une gangue de quartz ± chlorite; (2) "Stade principal" sulfures polymétalliques (Cu + Co + As + Ag + Au + Bi ± Pb ± Ni ± U), arséniures, et métaux natifs dans une gangue de calcite; et (3) "Stade tardif" calcite massive ± galène. L’altération pénétrative de la Diabase de Nipissing est confinée à des halos étroits (<5 cm) présentant des assemblages marquées par la présence de calcite-chlorite-épidote, tandis qu’un faible halo d’altération en hématite spéculaire, calcite et en allanite-épidote est noté dans les roches sédimentaires environnantes. De par leur âge, leur géologie, leur minéralogie leur paragenèse et leur morphologie, les systèmes de veines aurifères de Merico-Ethel ressemblent beaucoup aux gîtes filoniens d’argent-sulfoarséniures des camps miniers historiques de Cobalt et de Gowganda. Ces observations indiquent que ces veines aurifères constituent une variante des systèmes des veines argentifères et qu’elles partagent"

Jan 1, 2009

By B. Tougas

Recycling of titanium represents an important economic activity due to high cost of the material and the amount of returns of machined parts which represent the bulk of finished titanium products (typical "buy to fly" of 10 in the aeronautic industry). In the present work, the metallurgical quality of 76 mm in diameter and 20 cm ingots poured in coated graphite mold will be assessed against the nature and condition of application of 4 coatings namely aluminum oxide, yttrium oxide, zirconium oxide and zirconium oxide with 4% aluminum oxide. The metallurgical quality has been evaluated in terms of alpha case thickness, microstructure and composition. Microhardness from surface will be assessed against casting conditions. Least square regression analysis have been use to optimize casting conditions.

Jan 1, 2011

By Patrick S. Hudd

Traditionally in hard rock mining, large diameter raise boring was thought of as 3.04 metre or 3.66 metre diameter holes 300 metres deep. Mine and ventilation engineers were challenged to design systems either incorporating such holes, or slashing and modifying to suit. Now, 5.49 metre diameter holes up to 1,000 metres deep are being excavated. The ability to pilot and ream such holes not only creates new options for mine engineers in mine ventilation system design, but also creates new opportunities in mine access. By combining holes of this diameter with the ability to accurately drill long pilot holes within the diameter of the pilot hole through the entire length of the hole, borehole hoisting systems are now fully capable of being main production or service accesses for mines. This paper will review the present day capabilities of large diameter raise boring, potential applications for such excavations and some considerations for companies contemplating using large diameter raise boring in their operations

Oct 1, 2010

By L G. White

During 1958, prospecting parties working for the Mackenzie Syndicate in the Flat River area of the Mackenzie mountains, Northwest Territories, identified tungsten mineralization and located the property now being developed by the Canada Tungsten Mining Corporation Ltd. Scheelite mineralization, associated with pyrrhotite and minor chalcopyrite, occurs in lime silicate skarn replacement zones within a limestone-chert-argillite series intruded by granitic dykes originating from the ? main batholithic mass underlying the sedimentary beds. The results of surface outcrop sampling and 15,000 feet of grid-pattern diamond drilling have been combined to outline an orebody estimated to contain 1.32 million tons, grading 2.51 per cent WO after applying a 10 per cent dilution factor for mining purposes. T HE property of Canada Tungsten Mining Corporation Ltd. is located in the upper Flat River area of the Mackenzie mountains, Northwest Territories. Skarn-type replacement deposits containing scheelite mineralization are .situated between elevations of 4,500 and 5,500 feet above sea level along the east flank of the mountain range forming the boundary between the Yukon Territory and the Northwest Territories. The nearest supply center for the area is Watson Lake, Yukon Territory, located at Milepost 635 on the Alaska Highway.

Jan 1, 1963

By Dwight Newman

This paper discusses the author?s work identifying international law norms of consultation with indigenous communities and poses a potentially counterintuitive argument that corporate stakeholders? interactions with indigenous communities may have effects on the content of those norms. The claim is counterintuitive because the international law of pertinence is customary international law, which arises from consistent state practice and opinio juris (a belief by states that they are acting in a way they are legally bound to do so). Customary international law traditionally has no reference to corporate conduct per se. The paper first surveys several sources on developing international law on consultation obligations. Then it references the impact these norms can have on corporate stakeholders in industries like mining. Then, it poses an argument as to an economic ratcheting effect that can occur through various agreements between corporate stakeholders and indigenous communities that then feeds through into international law via several mechanisms. The consequences for mining companies are diverse and include the possibility that conduct by one company can have longer-term implications for the obligations of other companies and, indeed, of states. The effects will differ in the context of different competitive environments and may actually have effects on the economics of different competitive models.

Aug 1, 2013

By J. B. McKay

It is the purpose of this paper to present an initial report on the construction and operation of the Fluo-Solid roaster at the property of Campbell Red Lake Mines, Ltd., Balmertown, Ontario. The roaster prepares for subsequent cyanidation the bulk flotation concentrate obtained from four hundred tons per day of gold ore. The mill flow-sheet &apos;includes jigging and amalgamation; flotation; cyanidation of flotation tailing; and roasting followed by cyanidaition of flotation concentrate plus amalgamation tailing. Overall mill recovery for the year 1950 was 90.2 per cent. Recovery possible by straight cyanidation of this ore would not exceed 80 per cent. The ore contains considerable arsenopyrite and pyrrhotite as well as pyrite, with lesser quantities of nickel, zinc, and copper minerals. The mineralization is for the most part extremely fine. The roaster first went into operation on August 7th, 1949, and at the end of 1950 it had roasted 10,916 tons of concentrate. The average recovery of gold from calcine during that period was 94.86 per cent in the primary stage of calcine cyanidation. The average assay of calcine residue from primary cyanidation for the entire period was 0.37 oz. per ton. Both laboratory tests and plant metallurgical balance calculations indicate a further recovery of approximately 10 per cent of this 0.37 oz. when the calcine residue is again cyanided, in the flotation tailing cyanidation circuit.

Jan 1, 1951

By A. van As, J. McGaughey, M. J. Mol, R. Tosen

Geotechnical monitoring is a key element of the successful management of a block cave mine. The interrelationships between production and various monitoring datasets are often not realized due to a lack of data integration and appropriate 3D visualization. Timely delivery of information to ensure best cave management practices is only possible with an integrated cave management system. At Rio Tinto, a state-of-the-art cave management system (CaveCAD) has been designed and developed in cooperation with Mira Geoscience to integrate and analyze vast datasets and report this as instructive information regarding the current \u201cstatus\u201d of the cave.

Jan 1, 2014

By E. V. Konopleva, H. J. McQueen

"The isothermal bainite transformation kinetics of low- and medium-carbon alloy steels after hot deformation and the rmocycling treatment (TC) has been studied by the magneto - metric method. Deformation was produced by rolling at 800°C-1000°C. TC included three cycles of rapid (30°C/s) electro-heating up to 900°C-1000°C followed by quenching.Hot deformation retards bainite transformation in the lower part of bainite range (<400°C) and accelerates it in the upper part (>400°C). The effect is greater for higher strain and lower deformation temperature. Deformation also diminishes the overall bainite fraction below 400°C and increases the completeness of reaction above 400°C.Thermocycling provides more uniform ultrafine austenite grains with average size of 3 µm -4 µm compared to 12 µm -14 µm after conventional heating. The transformation rate after TC was almost the same as after conventional heating in low-carbon steel but was faster in medium-carbon with no change in the completeness of reaction. The degree of acceleration increased with rise of transformation temperature.There are a number of factors which are responsible for a change in bainite transformation kinetics in austenite deformed at high temperatures or subjected to TC. One of the most important factors is the refinement of structure, another one is structural and chemical inhomogenity of austenite due to deformation or to rapid heating. To estimate the contribution of these factors, ?-transformation was studied after different austenitizing conditions (low-temperature heating at 850°C- 950°C; high-temperature heating at 1100°C; step treatment – austenitizing at 1100°C, then cooling to 950°C-850°C). The results obtained make it possible to conclude that the structural and chemical inhomogeneity of austenite activate the bainite reaction while the grain refinement retards it. Intensity of the effect produced by each factor depends strongly on the steel composition."

Jan 1, 1997

By K. Adham, T. Buchholz

"Significant capacity increases to meet new production demands can often be fulfilled through debottlenecking of an existing production facility, rather than the more expensive option of building new plants and facing new environmental and infrastructure challenges. To achieve that goal, it is important to model and calculate the existing ultimate capacity of each processing plant area, and that of each key equipment sector within the plant areas. This paper describes a methodology of how process modeling tools can be used to simulate the processing steps, how to estimate their existing and ultimate capacities, and how to determine the sweet-spots (minimum cost points) for a plant expansion – leading to a road map of the subsequent debottlenecking project implementation.The debottlenecking technique is presented through a generic work-flow narrative which can be applied to different mineral processing studies, starting with establishment of heat-and-mass balances, drawing a bottleneck diagram, brainstorming capacity increase options, and preparing a cost-capacity curve. Hatch has successfully applied this technique to a number of plant capacity studies, with great benefits to our industrial clients.INTRODUCTIONWith the softening of the metals and minerals prices, and the escalated costs of building new processing plants, it is now economically more viable to improve and debottleneck the existing facilities, rather than build new ones. However, spending new money on old plants requires careful considerations, in order to identify the most economically advantageous incremental steps of improvement and the best potential returns on investment. Process modeling, hand in hand with plant measurements, can identify the best scenarios to balance the three aspects of plant capacity (nameplate, utilization and yield), both at the global and the individual system and subsystem levels."

Jan 1, 2016

By Paolo Toscano, Dave Hall

"This paper discusses the project history, process design and layout of the Rainy River Gold Project mill. The circuit consists of a 55 x 83 primary crusher, 15 MW SAG mill and 15 MW ball mill. Both mills are twin pinion with LSS and VFD drives. A pebble crusher is located in the process plant with bypass and stockpile options. Gravity concentration followed by 30 hours of leach residence, carousel CIP, carbon recovery, cyanide destruction and tails disposal in a 1,428 hectare tailings management area (TMA).The Rainy River Gold Project is located approximately 65 km northwest of Fort Frances in north western Ontario. The project is scheduled to be commissioned and reach commercial production in mid-2017. Expected cost is $US877M and is comprised of an open pit mine, process plant, tailings management area and supporting infrastructure. The process plant is designed to produce gold/silver Dore’ bars.The project has been developed on the following timeline:• 1967 – First exploration• 1994 – 17 zone discovered• 2004 – 433 Zone discovered• 2005 – Rainy River Resources Ltd. purchases property • 2006 - ODM zone discovered• 2007 - Cap Zone discovered• 2008 - First NI-43-101 Resource completed• 2012 - PEA completed & Intrepid Zone discovered• 2013 - New Gold acquires Rainy River Resources• 2014 - Updated feasibility study completed & Environmental Assessment report submitted• 2015 - Detailed Engineering >95% complete, EA approved and construction commencesThe property is accessed by provincial highway 600 and is within 17 km of 230 kV power line and railway sidings. Key project criteria are summarized as follows:"

Jan 1, 2016

By Simon D. Handelsman, Malcolm Scoble, Marcello Veiga

"Abstract - In many mining areas, potentially profitable mineral projects can be at risk because local people do not trust their governments and mining companies on many issues, including human rights. Projects will continue to be vulnerable to potential failure, delays, and higher costs. This paper suggests that geoscientists need to be aware of the global challenges they face from issues of corporate social responsibility, sustainable development, and human rights. These are not areas in which geoscience education has traditionally focused.This paper examines the types of conflict concerning human rights that are encountered by geoscientists involved in mineral exploration and development. It provides a background to human rights issues and presents a classification of the types of issue encountered. It reports on a survey of case studies that provide examples of the breadth, complexities, and consequences of such issues. The paper then concludes by outlining the development of codes and standards to improve performance, and suggests approaches for positive, practical engagement."

Jan 1, 2003

By A. Bowles

The process of accumulative roll bonding (ARB) has been applied to wrought magnesium alloy AZ31. Accumulative roll bonding results in severe plastic deformation of sheet material. In AZ31, this process leads to the refinement of the microstructure by dynamic recrystallization. The refinement of the microstructure results in an improvement in mechanical properties with potential for producing materials for superplastic forming. In this work AZ31 was bonded with up to 64 layers and the potential of roll cladding with aluminium was also investigated. The development of microstructure and the mechanical properties are reported here.

Jan 1, 2006

By B. Kenney

For SOFCs, composite cathodes comprising an electronically conducting electro¬catalyst (e.g. LSM) and an conically conducting electrolyte material (e.g. YSZ) are considered to improve the electrochemical performance by extending the active reaction zone to regions beyond the electrolyte-electrode interface, as in the case of conventional cathodes. Interpretation of experimental data for composite cathodes, however, is complicated by the mixed conducting behaviour which results in local overpotential distributions throughout the composite cathode. These local overpotentials depend on many factors, such as the composition, particle size, porosity and thickness of the cathode. Reliable experimental data obtained from composite cathodes requires carefully crafted microstructural parameters in order to minimize the overpotential variations. A mathematical model of a composite cathode was developed using coupled differential equations describing transport and consumption of chemical species, oxygen ion and electrons. Simulations under various oxygen concentrations were used to obtain the reaction order of the oxygen reduction reaction. An apparent po2 dependency was then extracted from the predicted Rp vs P02 data. It was found that this p02 dependency can be significantly influenced by the micro-structural parameters of a composite cathode, primarily due to local overpotential distributions.

Jan 1, 2005

By P. A. Witt

"Highland Valley Copper is a conventional truck-shovel mining and flotation concentrator operation located 75 km southwest of Kamloops, British Columbia (Fig. 1).The ore is situated within a porphyry copper deposit and is mined at a rate of 135,000 mt/day from two separate open pits. The nearby mill produces concentrates containing 375 million pounds of copper and 5 million pounds of molybdenum metal yearly. In the Valley pit, head grades are roughly 0.40% Cu at a 0.23% Cu equivalent cut-off. The Valley pit strip ratio currently sits at 0.55:1 with waste quantities made up of separate rock and unconsolidated overburden units. From the mill, concentrates are trucked to nearby Ashcroft and then hauled by rail to ocean port facilities in Vancouver. The mine employs 950 people and is planned to operate until 2009. The operation is a partnership between Teck Cominco (63.9%), BHP Billiton (33.6%), and others (2.5%). Management is shared by the two principal owners and directed by a management committee."

Jan 1, 2005

By E. P. Cadwell

"Throughout the years Cyanamid has been a supplier of cyanide and a supplier of information to the mining industry. In general, the knowledge of mineralogy is greatly overlooked. Mineral deposits in the Western hemisphere have been exceedingly rich in the past but now they are becoming poorer. In other words, we will have to use our talents to the utmost to extract the precious metals and base metals from these ores. Modifications of some of the mineralogical equipment displayed here belong in the mill.Cyanidation of copper has been one of the main projects in our labs in recent years. De-rimming or de-filming of copper in order to upgrade copper concentrate was the main aspect investigated. A study was made as to how wide spread was the filming of secondary copper on pyrite, and to what extent it affected the copper industry. It was very wide.Often there is no conception as to what the minerals are. One open pit copper producer with a chalcopyrite ore was producing a copper concentrate with a 5% copper value whereas chalcopyrite contains 35% copper. They used primary and secondary grinding and a regrinding section. The ore contained about 8 parts chalcopyrite to one part of other copper minerals. In tests, a 3 1/ 2% copper rougher concentrate, cleaned without regrinding but conditioned with cyanide for a low contact time of 30 seconds produced a 30% copper concentrate with 90% recovery by removal of the film. It was of utmost importance that some quantitative mineralogical analysis be made before flow sheet changes were made. Every man should be trained to do his own microscopic examination in order to get quick answers. The fundamental thing in all mineral dressing is to first of all know the minerals and the mineral associations."

Jan 1, 1964

By Jianping Zhang

QUESTIONS: ?? Is it more expensive to find an ounce of gold in Canada today than 50 yrs ago? ?? Did the Canadian gold industry find more gold than they mined? ?? What is the future sustainability of the Canadian gold industry? ANSWERS: ?? The gold discovery costs in real terms only increased slightly from 1946 to 2000. ?? Though the Canadian gold industry mined more gold than they discovered in the period, when undeveloped deposits are taken into account, the deficit was merely 12 million ounces. ?? The Canadian gold mining industry would be sustainable in the foreseeable future, particularly, given the overwhelming predicted promising gold market in the mid/long run.

May 1, 2006

By S. P. Lowe

Flotation testing of Flin Flon ore was started in the Denver laboratory of Complex Ores Recoveries Co. in March, 1926. There had been a considerable amount of flotation testing previously which had shown possibilities of success, and it was felt that, with the increased knowledge of flotation and the comparatively new reagents then available, flotation held out the best prospects for a successful commercial treatment of this ore. There remained available for this experimental work a small amount of the rejects from a thorough sampling of the mine and some ore from the mine dump.

Jan 1, 1930