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By Robert Y. Lamarche

On exploite le chrysotile dans le sud du Quebec depuis plus de cent ans. Au cours des dernieres decennies, cette variete d'amiante est devenue une des principales substances minerales produites au Quebec. Bien que la production de fibres d'amiante ait diminue de J 365 779 ten /979 a que!que 700 000 ten 1983, le Quebec n'en demeure pas mains une des principa/es sources d'approvisionnement mondial de ce mineral, la valeur des exportations quebecoises ayant ete de l'ordre de 315 millions de dollars en 1983. Dans la presente contribution, nous passons en revue que!ques-unes des notions mineralogiques sur l'amiante, depuis l'etymologie du mot et les proprietes physico-chimiques du mineral, jusqu'd ses principales utilisations commercia/es et industrielles. Un des deux objectifs principaux de noire article est de definir brievement le contexte geologique regional, la lithologie et /'age des roches ultramafiques serpentinisees et de decrire les principales caracteristiques des gftes de chrysotile qu'elles renferment et qui furent exploites a date dans /es Appa/aches du sud quebecois. Nous concluons en dressant un tableau synoptique de la metallogenie et en soulignant le role preponderant qu 'ont joue /es mouvements tectoniques majeurs, a la jonction des plaques et au sein des feuillets et copeaux de la croute oceanique (lithosphere et manteau superieur), sur la genese des gftes de chrysotile dans les roches ultramafiques serpentinisees, et tout particu!ierement dans celles associees aux series ophiolitiques du Paleozaique inf erieur.

Jan 1, 1984

By Pizhi Zhao, Jingwei Zhao, Zhenshan Liu, Yiheng Cao

"A new Al-Mg-Si-Zn alloy designed for automotive outer panel was trial-produced with industrial procedure. The final product shows a strong planar anisotropy. X ray diffraction analysis shows such strong anisotropy is caused by the dominating cube texture component in the final product. The reason for such high cube texture component was investigated by tracing texture evolution starting from the hot roll slab. It is found that certain cube texture components already exists in the hot rolled slab. The density of cube texture component shows as a wavy change through the following1st cold rolling, inter-annealing, 2ndcold rolling and solution treatment. This study shows that the cold rolling in the laboratory can well represent the texture evolution during the industrial production. The results obtained by lab rolling hints that change of second cold rolling reduction has weak effect on the planar anisotropy, when the gauge of hot rolled slab and final sheet are fixed.INTRODUCTIONWith the rapid progress of light-weighting in the automotive industry, aluminum sheets get more and more application as closure panel and structure parts. Recently the dominating alloy for outer panel is 6xxx series, containing the main alloy elements Mg and Si. The popular gradesareAA6016,AA6111, AA6022, and AA6014. These alloys still cannot satisfy the various requirements from automotive manufacturers. Most suppliers of automotive aluminum sheets are developing their own specific grades according to the customer’s demand. To increase the baking response, anew Al-Mg-Si-Zn alloy was designed, concerning the high combination energy between Zn solutes and vacancies formed during the quenching stage of automotive sheet manufacture. This combination is helpful to the precipitation of ß”phase during the paint baking (Wang, 2015,2016; Yan, 2014).The plastic strain ratio (r value)is a key index of the formability of automotive body sheet. A high r value means a good formability. The r values in different directions can be used to evaluate the planar anisotropy of the metal sheets. The trial produced Al-Mg-Si-Zn sheet shows a strong planar anisotropy with respect to r values. Since the r value is tightly related with texture, the texture evolution from hot roll slab (HRS) to final T4P temper was analyzed with X ray diffraction (XRD) to find the reason for the high anisotropy. Besides, the cold rolling reduction (CRR) was varied in the laboratory to modify the texture distribution, i.e., the planar anisotropy."

Jan 1, 2018

By F. Ajersch, M. Rigaud, M. Jallouli

"Le gonflement des boulettes d'hématite à été étudié à l'aide d'une méthode de mesure standard ISO ainsi qu'à l'aide d 'une méthode de mesure dilatométrique.La première méthode a servi à l'étude des boulettes haute silice (5% SiO2) dont l'indice de basicité (IB = CaO + MgO -i- SiO2 + Al2O3) a été ajustée soit à l'aide d'une addition de dolomie, soit à l'aide d'une addition de pierre à chaux, soit à l'aide d'une addition de ces deux composes. L'indice de basicité variait de 0.05 à 0.12. Les résultats de gonfle ment obtenus à 1000?C dans une atmosphère de 40 CO - 60 N2 ont permis de montrer qu’indépendamment de l'indice de basicité c'est la dolomie qui contribue le plus à diminuer le gonflement par rapport à la pierre à chaux. L'utilisation de l'indice de basicité comme critère de sélection des boulettes est discutée.La méthode dilatométrique a servi à l'étude du gonfle ment de deux types de boulettes préparées à partir de deux concentrés de fer et dont la teneur en silice a été fixée à 2.5% et 0 5%. Ces deux types de boulettes ont reçues les mêmes additions de liant en quantité et en nature. La détermination en continue du gonflement, à 950?C dans 40 CO - 60 N2, a permis d'une part de mieux cerner le niveau de réduction auquel correspond le maximum de gonflement et d'autre part de montrer que l’allure des courbes de gonflement est étroitement liée à la nature du liant. Une augmentation de la teneur en silice des concentres contribue à diminuer le gonflement des boulettes.Des essais de réduction de gonflement non isothermes ont été réalisés à des montées de température à 10 et 20?C/min. Les résultats indiquent que le gonflement déterminé dans les conditions non iso thermes est inferieur à celui obtenu lors des essais isothermes. On discute alors de la validité des essais standards de gonflement qui sont utilisés pour prédire le comportement des boulettes lors de leur réduction dans un haut fourneau."

Jan 1, 1983

By J. G. Thomson

Development of the Canadian North, a subject of growing national interest, must in part await the development of better forms of trans-port. The estimated 500,000 square miles of muskeg terrain in the north combined with the" scarcity of roads make essential the early development of special purpose muskeg vehicles. Good progress has been made in the last eleven years in classifying muskeg and some progress has been made in determining its mechanical properties. Limited travel is now possible through the use of special purpose tracked vehicles which have been built without adequate design data. A program to provide data which can be used to optimize muskeg vehicle designs began in 1957. The results of the second phase of this pro-gram are presented in this report. It is shown that vehicle performance in muskeg is directly related to the mechanical properties of the muskeg. Further, it is shown that good de-sign practice for tracked vehicles expected to operate in snow, sand, soft clays and loams is also good practice for muskeg vehicles. All indications are that muskeg mechanics is properly a part of conventional soil mechanics.

Jan 1, 1961

By M. Kucharski

The model of the Outokumpu direct-to-copper process deals with a steady-state process the parameters of which do not depend on time. To give a prediction for the process outcome, "a modified black box" method, which ignores most of the chemical reactions in the furnace, was used. This method takes input and output parameters into consideration. The presented model describes the Outokumpu direct-to blister process in the form of the set of linear equations which give mass and enthalpy balances as well as the distribution of elements between blister copper and slag. However, only major substances where quantities in the feed charge exceed a certain level (for example 0.5 kg/ lMg of smelted concentrate) are taken into consideration. Minor elements are distributed among slag and metal phases in a different way. Some of the equations are derived from distribution coefficients. The value of distribution coefficients can be calculated from plant production data.

Jan 1, 2007

By G. C. Hambleton

"The author has had wide experience in the reclamation of coal from coal mine waste dumps in the United Kingdom.The paper includes such topics as the processing decision and factors affecting processability; method of testing and appraisal; test data interpretation; historical influences in apppraisal; special contaminants and processing difficulties; methods of treatment; review of systems in use and their comparative economics; over-all system economics including excavation, handling methods, recovery system and shale disposal; effluent treatment; environmental considerations; alternatives to processing for coal recovery; light aggregate and cement usage; burned shale heaps; land reclamation; shale deposition for encouragement of vegetation by natural or artificial means; use of tailings fines; the environmental argument for action."

Jan 1, 1972

By D. Yu, T. A. Utigard, M. Barati

"Sulfation roasting of nickel concentrate to generate water-soluble metal sulfates was investigated as an alternative process to smelting for the recovery of valuable metals. The kinetics of dissolution of various species of the calcine in three leachants was studied; hot water, dilute HCl, and concentrated HCl. The results indicated that dissolution of sulfates by hot water at 90 ºC is achieved within 30 minutes. In order to increase the recovery of the valuable metals, acid leaching is necessary due to the existence of ferrite in the calcine.INTRODUCTIONInvestigations on the sulfation roasting of nickeliferous sulfide ores or concentrates were mainly carried out in 1950’s to 1990’s to generate water soluble non-ferrous metal sulfates followed by metal recovery by leaching (Stephens, 1953; Thornhill, 1954, 1961; Fletcher and Shelef, 1964a, 1964b; Fletcher and Hester, 1964; Frankiewicz, 1977; Norrgran, 1983). Commercialization of the sulfation roasting process was only performed by Falconbridge Ltd. (Thornhill, 1961; Boldt, 1967), which employed a sulfation roast process on nickeliferous pyrrhotite at 680 oC where Ni, Cu, and Co were leached and Fe2O3 was produced for the iron industry. In 1965, 118,342 tons of pyrrhotite was processed, however because of the huge SO2 emissions (no acid plant) relative to the nickel production and the poor economics, this plant was shut down.Nickel production from sulfide ores via pyrometallurgical means, especially the electric furnace smelting process, is a major emitter of SO2 to the environment and a big energy consumer (Warner, Diaz, Dalvi, Mackey, Tarasov and Jones, 2007). Nowadays, due to the more stringent environmental regulations as well as the need to reduce energy consumption, metal production by sulfation roasting is gaining more attention as an alternative process to smelting. The main focus of this paper is to investigate the extent and rate of leaching of valuable metals from the sulfation roasted nickel calcine, aiming to maximize the metal recovery and minimize the dissolution of iron species."

Jan 1, 2012

HIGH LAKE PROPERTY --HISTORYHISTORY -19501950??s ??Kennarctic Exploration discovers Exploration sulphides (A/B & (D Zones) at High Lake during helicopter reconnaissance exploration program.- -1991 93 Aber signs agreement to earn in to the High Lake Property from Kennecott. 63 holes drilled, primarily testing the known deposits. -2001 Wolfden purchases 100% interest in High Lake from Kennecott and Aber -2002 Wolfden performs helicopter borne TEM Survey over the High Lake Greenstone Belt. -2003 West Zone was discovered following UTEM & Gravity Surveys (performed by Teck Cominco ) over an airborne anomaly approx. 1km west of the known deposits. -2004 Wolfden awarded Bill Dennis Prospector of the Year

May 1, 2006

By M. Peshko, J. C. Gingerich, L. W. Matthews

"Noranda has successfully developed and implemented two leading-edge mineral exploration technologies — hyperspectral remote sensing and 3-D seismic surveying. Airborne hyperspectral imaging provides detailed geological and mineralogical mapping capability at both a regional and project scale that facilitates improved selection of prospective terrain and an accelerated exploration cycle. Noranda, in partnership with Falconbridge, has licensed the exclusive use of the Earth Search Sciences Inc. (ESSI) Probe-1 hyperspectral scanners (128- channel, 0.43 µm to 2.5 µm spectral range) that are capable of mapping in excess of 3500 km2 per day at 10 m pixel resolution. The technology has been successfully deployed on four continents over a broad range of terrain from desert to boreal forest and the high Arctic.To augment the company’s deep search initiatives, Noranda has successfully modified and implemented existing 3-D seismic technology to help targeting massive sulphides located at depths ranging from 500 m to 2000 m. In the fall of 1998 and early 1999, Noranda completed an 18 km2, 3-D seismic program in eastern Canada by successfully drill testing acoustic impedance anomalies locating massive sulphides at depths in excess of 1100 m."

Jan 1, 2002

By T. H. Patching, D. F. Coates

The Sub-Committee on Rock Classification, Canadian Advisory Committee on Rock Mechanics, has evolved a classification of rocks which should prove useful in studies of rock mechanics. Considered in two stages -actual rock substance and rock mass -the five-point classification involves the geological name of the rock, the rock strength and rock deformation, and, in the second stage, the gross homogeneity of the rock mass and the formation continuity.

Jan 1, 1968

By Holly L. O. Huyck

Disseminated hypogene sulphide mineralization in the Lakeshore porphyry copper deposit (also called the Cyprus-Casa Grande deposit) of Arizona occurs in both a granodiorite stock and associated volcanic rocks. Structural development and vein paragenesis at Lakeshore are similar to other Laramide porphyry copper deposits of the southwestern U.S. Two major structural trends are present: intrusive contacts, copper-bearing potassic alteration veins and major post-mineralization Basin-and-Range type faults trend N-NW, whereas phyllic veins and secondary post-mineralization faults trend N-NE, and deep propylitic veins trend NE-ENE. Lithologic permeabilities, caused by fracturing in all rocks and by grain size distributions in volcanic rocks, controlled the distribution of copper mineralization. Differences in chemical compositions of host rocks did not affect are grade. Structural control, through density of chalcopyrite-rich veins, was the major control of are grade. Fracture density of other potassic vein types did not strongly affect grade. Within volcanic lithologies, permeability, as indicated by grain size distribution, provided a second-order, but significant, control of mineralization.

Jan 1, 1990

By S. Kelebek, B. Nanthakumar

ABSTRACT The sensitivity of sulphide minerals towards oxidation depends on the mineralogical makeup and nature of sulphide ores. This paper focuses on chalcopyrite behaviour in a nickel-copper sulphide- ore matrix that was aged in the mine-site stockpiles. Results of collectorless, collector-induced flotation and recovery by size are presented following a discussion of XPS analysis that was used to gain insight into oxidative alteration of chalcopyrite’s surface chemistry. Chalcopyrite maintains its high flotation activity despite exposure to weeks of oxidative conditions. It is concluded that chalcopyrite is quite tolerant to stockpile oxidation due to various factors related to alteration of its surface chemistry.

Jan 1, 2012

By G. W. Evatt

This paper presents the scientific framework underpinning the Resource Valuation and Optimisation Model (RVOM). The RVOM is a Real Options software package, which helps mine owners optimally plan their operations, understand their project risks, and make defensible valuations. This is achieved in the presence of both financial and physical uncertainty. The three key outputs from the RVOM are: Valuation, Optimal Decision and Probability of Decision, where a decision can include any combination of: normal operation, expanded operation, care and maintenance, and abandonment (and variants thereof). This paper presents a clear example of the RVOMs usage to a case-study gold mine.

Jan 1, 2011

By C. Hudson, D. Tremblay, A. Frey

"A discussion of the design, challenges and successes associated with the commissioning of the gravity recovery circuit at Canada’s newest open pit gold mine - Atlantic Gold’s Moose River Consolidated Project in Nova Scotia, Canada is presented. An overview of the project, its historical significance and overall flowsheet is provided with special focus given to the design and selection of the gravity circuit equipment including the scalping screen, gravity concentrators and the novel intensive leaching technology selected for the project. The performance of the gravity circuit is benchmarked against the feasibility study process design specifications and the outcomes are discussed. Challenges encountered during commissioning are also presented, including the use of third-party automation and the effects of screen sizing on overall gravity circuit performance. Mechanical modifications made to the Sepro Leach Reactor for the Moose River project are also discussed. A detailed technical review of the mechanical and operational aspects of the Sepro Leach Reactor is provided with key operational data on leach times, recoveries, reagent usage, solid-liquid separation, pregnant solution quality and its influence on bullion purity.INTRODUCTION Atlantic Gold Corporation’s Moose River Touquoy Mill in Nova Scotia, Canada was commissioned in the fourth quarter of 2017 with commercial production declared in March of 2018. The 2 Mtpa process plant uses a conventional, gravity-CIL process. This site was previously mined in the 1870s. Interest waned in the early 1900s but resumed in the 1930s and the mine was brought back into production in 1935 until an underground mine collapse in 1936. This mining district became famous after CRBC radio commenced a ground breaking, around the clock, broadcast of the rescue operations. Over 100 million people listened to the broadcast from Canada, the United States and the United Kingdom. These broadcasts changed radio, transforming it from a medium for music to on the spot, breaking news reporting. The mill was constructed by Ausenco on a fixed price EPC contract in the historic Moose River gold mining district, 95 km north-east of Halifax by road. The mill will process ore from the adjacent Touquoy pit for the first 5+ years of operation; after the Touquoy reserves are exhausted, the mill will process ore trucked 37 km from the Beaver Dam deposit for an additional 5 years."

Jan 1, 2019

By Yan Germain, Université Laval, Bernard Dallaire, Jocelyn Bouchard, Peter Radziszewski, Gilles LeBlanc, Michelle Levesque, Nicolas Tremblay

"The comminution process is estimated to be only 1% efficient, resulting in waste energy dissipated as heat, noise, and vibration. Energy recovery from grinding circuits has not been implemented mainly because recovering heat from the surface of the grinding mill or from mill slurry can impede operation, increase maintenance requirements, and prolong plant shutdown time (and production). However, currently very little information is available in the public domain regarding the amount of waste energy and that potentially recoverable in the grinding circuit of a mineral processing plant. Availability of such information could drive innovation and improve decision-making regarding opportunities for waste energy recovery. The Canadian Mining Innovation Council (CMIC) has initiated a study with CanmetMINING and mining industry partners to develop a model to map the energy flows in grinding circuits and to quantify the potential for energy recovery. The paper outlines the underlying fundamentals and data requirements for use in the model and then focuses on quantifying the energy recovery potential of the semi-autogenous grinding and ball mill circuits at the Agnico Eagle Goldex Division. Results show that most of the electrical energy (over 75%) is used to heat the slurry, leaving only a relatively small amount of it to achieve mechanical work (~9%). INTRODUCTIONCanmetMINING commissioned a study in 2013 to better understand the barriers for adoption of new technologies in the mining industry (MNP, 2013). The conclusions highlighted the importance of enhancing industry/regulator engagement and communication to raise awareness and improve the industry’s comfort level with new technologies.In November 2014, the Green Mining Innovation Advisory Committee (GMIAC) held a workshop to explore the possibility of accelerating the uptake of green mining technologies by bringing together key stakeholders among the mining value chain to address industry priorities. Participants included representatives from mining companies and associations, academia, provincial governments and federal departments and organizations. Two key priority areas emerged at the workshop: i) energy saving, and ii) water management."

Jan 1, 2016

By Richard J. Kolada, Ian R. Muirhead

"This paper reports on a CANMET-funded examination of less conventional underground coal mining methods. These methods are documented and those that show the most promise for application to western Canadian conditions are discussed in detail.IntroductionIn recent years, mining considerations and economics have encouraged a transition from underground mining to surface mining. However, a change in market conditions or the development of superior underground mining methods may reverse this trend . Should this happen, the industry must be quick to respond and have information available on the latest developments of underground mining technology. In time, deposits of high-quality coal, which are easily accessible to surface mining, will be depleted and a change to underground mining methods will require consideration. The economic transition point between surface to underground will be a major determinant in maintaining a competitive edge. For these reasons, it is important to keep abreast of improvements in underground mining methods. To meet this objective, CANMET awarded a research contract to Monenco Consultants Limited, to investigate unconventional underground mining methods that show a potential for western Canadaoi. This paper presents the results of this investigation."

Jan 1, 1988

The process of gold recovery by gravity concentration is incorporated in the metal recovery flowsheet at seven Newmont Mining Corporation owned mining operations in Australia, North America and Africa. In 2009 gold recovered by gravity processing was equivalent to nine percent of Newmont's total gold sales of 5.3 million ounces. This paper will discuss these applications in detail including a review of plant flowsheets and presentation of recent operating results. Operating performance will be discussed with reference to ore characterisation procedures, interpretation of results, design considerations and optimisation practices as they relate to the recovery of gold by gravity concentration.

Jan 1, 2011

By D. E. Keeley

lntroduction Some years ago it was general practice in Canadian mines to use the best timber available, just as it was cut from the tree. Later, to prevent 'borers' from getting into the wood while stacked in the yard, the bark was peeled off, cleaned up carefully, and burned to eliminate a breeding ground for these and other destructive insects. This practice of good housekeeping also decreased the hazard from fire in scattered bark. A few years after damage by borers had been minimized, it became apparent that increased temperatures in the mines, occasioned by deepening operations, were being accompanied by rapid growth of fungus and by decay in timber underground, greatly shortening its life. In places on upper levels where the air temperature was below 50 deg. F., untreated timber retained a large proportion of its strength for ten or more years. In other places on these levels, however; its life was short and it developed much dry rot and merulius lacrymans. In these latter places and on lower levels in the mine where temperatures ranged from 50 to 60 deg. F., approximately, the wood became infested with extensive growths of this white fungus. This development was accompanied by the production of millions of spores. Spread of infection was due mainly to the transfer of spores from the warm lower levels to the cool upper horizons by upcasting ventilation currents. So serious did this become that about twenty years ago Lake Shore, Hollinger, and McIntyre Mines decided to investigate the use of wood preservatives and the plant necessary to treat timber.

Jan 1, 1949

By Yoginder P. Chugh

This paper discusses an ongoing field study in southern Illinois (USA) that focuses on: 1) Identifying mechanisms of instability in the set-up rooms (SR) and their T-junctions with headgate and tailgate entries, 2) Developing alternate 3-entry and 4-entry set-up rooms geometry using 3-D numerical analyses, 3) Implementing developed geometries in cooperation with mining professionals and regulatory agencies, and 4) Demonstrating performance of implemented geometries through field monitoring. Illinois longwall mining operations typically experience ground control problems (roof falls, rib sloughing, floor heave, etc.) within SR layouts and around the T-junctions of SR. These occur around the areas where the SR for adjacent longwall face (to be mined) connect with the SR of the previously mined face, and around the tail-gate entries of the mined-out longwall face and around the T-junctions of SR. The problems manifest as highly fractured immediate roof strata, major shear zones in the roof, horizontal displacements within the excavations that result in shearing off the heads of the bolts, floor heave and severe rib sloughing. Similar observations have also been made in longwall mining in Utah.

Aug 1, 2013

By Yvon T. Maurice

Under the auspices of the Federal-Provincial Uranium Reconnaissance Program, a geochemical orientation survey was undertaken in an area of uraniferous Lower Proterozoic (Aphebian) rocks near Cape Dorset in southwest Baffin Island. The main objective of this study was to establish a methodology for a future reconnaissance geochemical program using lake samples over a 300-mile Lower Proterozoic rock belt that occurs along the southern coast of Baffin Island. Mineralogical and chemical studies of known radioactive occurrences, combined with detailed sampling of secondary environment media in the vicinity of the showings. indicate that uranium is the most significant pathfinder, despite considerable enrichment of other metals in the uraniferous rocks, Significant geochemical patterns produced by uranium in lake waters and uranium in lake sediments have been obtained, but their relative usefulness depends on the distribution of carbonate bedrock, which in turn affect the bicarbonate content of lake waters. In southern Baffin Island, because of erratic variation in lake-water alkalinity, it is recommended that both water s and sediments be sampled on a routine basis. The need for lake-water acidification to prevent depletion of soluble metal ions in samples resulting from adsorption on the walls of the containers and/or suspended solid matter is discussed briefly. The base metal potential of the area was examined in some detail and found to be significant, particularly for a Lower Proterozoic gossanous formation that occurs throughout southern Baffin Island.

Jan 1, 1977