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By Robert B. Parsons

"The Canadian Exploration Incentive Program (CEIP), which was announced by the federal government on May 3, 1988, promises to maintain the viability of flow-through shares as a financing mechanism which has proven to be so crucial to the health of the junior exploration sector. This month, Tax Notes examines, the main features of CEIP, which will come into play on January J, 1989. IntroductionOn May 3,1988, the Honourable Marcel Masse, Minister of Energy Mines & Resources, and the Honourable Gerald Merrithew, Minister of State (Forestry and Mines) announced the Canadian Exploration Incentive Program (CEIP). Under CEIP, the federal government will make cash payments to eligible applicants equal to 30% of eligible exploration expenses. CEIP payments will be available with respect to both mineral, and oil and gas, exploration. In essence, the program will replace the ""mining exploration depletion allowance"" (MEDA) presently applicable to mineral exploration, and the Canadian Exploration and Development Incentive Program (CEDIP) which is presently available to the oil and gas exploration sector.This paper discusses briefly the main features of CEIP insofar as the program will affect mineral exploration. The comments herein are based on the Canadian Exploration Incentive Program Act which received Royal Assent on July 21, 1988, and on a discussion paper which was released by EM&R in May 1988. The bulk of the rules relating to the program will be in the form of regulations which have yet to be finalized. It is understood that EM&R would like to have the regulations in force by October I, 1988, when the oil and gas portion of CEIP becomes effective. (The rules relating to mineral exploration will become effective January I, 1989)."

Jan 1, 1988

By James J. Scott

"In the two years since their introduction, Friction Rock Stabilizershave replaced40 per cent of the previously used fixtures in the metal and non-metal mines in the United States. The Friction Rock Stabilizer, or ""Split Set "" , is a mechanical rock stabilizing system which uses friction to prevent rock movement . The Split Set is a tapered, rolled, steel tube that is slotted along its length. As it is driven into a drilled hole smaller than its diameter, it compresses, pre-loading the surrounding rock. This paper discusses the uses and acceptance of the friction rock stabilizer in mines in the United States. IntroductionFriction Rock Stabilizers, commonly called Split Set™· Stabilizers, have been under development by the author and Ingersoll-Rand Company since early 1973. Five years of intensive laboratory and field testing led to their introduction to the metal mines in the United States in the fall of 1976. Actual sales started in February of 1977and, to date, over five million units have been marketed to metal mines. The present rate of usage is near 3 V2 million units per year, which is approximately 50070 of all roof fixtures used in the United States metal mining industry,Richard Hoppe, senior editor of Engineering & Mining Journal. , in an article in the February 1979 issue entitled ""Winning the Battle Against Bad Ground"", said: ""In hardrock mining operations in the western U.S., particularly underground uranium mines where exceedingly difficult ground is common, no roof support system has been accepted more quickly than the Split Set friction bolt invented by Dr. James J . Scott and developed by Ingersoll-Rand Co."" This paper describes how Friction Rock Stabilizers function and presents technical data to show the uniqueness of such systems."

Jan 1, 1980

By L. Bichler, C. J. Verdon

In this work, the effect of doping yttria stabilized zirconia (YSZ) with 5, 10 and 15 mol% erbium oxide (Er2O3, erbia) was investigated using spark plasma sintering (SPS) technique. Sintering was carried out at 1300°C with 30 and 60MPa uniaxial pressures and a 5min hold time. Densification kinetics were studied using displacement response from the SPS machine. As-sintered microstructure characterization was carried out via scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques, while chemical composition was characterized by energy dispersive X-ray spectroscopy (EDS). The results suggest that sintering carried out at 60MPa produced high density composites even though erbia dopants were found to inhibit material densification and grain growth during sintering. 5, 10 and 15mol% erbia- YSZ had cubic crystal structures, as verified by XRD analysis.

Jan 1, 2014

By R. M. Giegerich

"This paper begins with a brief history of Madawaska Mines, a brief description of the geology, mining methods and equipment, and the historical development of 7/8-in. tapered drilling equipment. It then outlines the performance characteristics and inherent problems of the traditional 12-degree, tapered connection, blade-type insert bits. Service-free (Unipass) button-type insert bits are presented as a possible solution to these problems. The paper concludes with an analysis of button bit performance to date.Brief History of Madawaska MinesMadawaska Mines Limited, near Bancroft, Ontario, is in Faraday Township, Hastings County, approximately 100 miles northeast of Toronto and 100 miles west of Ottawa.The mine re-opened in 1976committed to 1,500 tons per day to provide approximately 600,000 pounds of yellowcake (U3O8) per year to A.G.I.P. (an Italian government agency) under the joint ownership of Federal Resources Corporation, Salt Lake City (51%), and Consolidated Canadian Faraday Limited (49%). At present, the mine is producing approximately 2 pounds per ton (.1% U3O8) at the rate of 60,000 pounds per month. The mine employs about 400 employees.Brief Description of Geology, Mining Methods and EquipmentGeologyThe Grenville metasediments of the mine area are chiefly paragneiss, amphobolite and some carbonate (marble) rocks, which were intruded by a basic rock, altered to a metagabbrometadiorite. These formations are generally concordant, striking east to northeast and dipping 45 to 60 degrees to the south. Locally, the metagabbro is often discordant. The above group of rocks (mixed hybrid gneisses) forms the hanging wall of the south-dipping Faraday granite sheet and was intruded by nepheline syenite, syenite and granite. The ore occurs in the granite-syenite-pegmatite dykes that are probably genetically related to the Faraday granite. The ore shoots are erratically distributed within the pegmatite bodies, mainly on the hanging or footwalls but also medially. Their size varies from 50 to 350 feet in length, 5 to 40 feet in width and 50 to 200 feet in height. The ore occurs most frequently in a medium-grained granite or syenite, well hematized with 10 to 30% mafic crystals of pyroxene, amphibole and/or relics of the host rock."

Jan 1, 1982

By Theo Mayer

Presentation Outline Define data visualization in the context of workflow Present other industries? application and demonstrated benefits Provide conceptual tools to help you address a visualization strategy Hold 10,000 foot view ? to touch on many issues

May 1, 2008

By K. N. Karparov

?Two highwall failures in a South African coal mine defied analysis by widely accepted limit equilibrium methods. ?The geological conditions were complex, with undulating coal-bearing strata overlying a karstic topography formed in underlying dolomite belonging to the Transvaal Supergroup. ?It was clear that the simplifying assumptions made by all limit equilibrium methods were inappropriate in the conditions.

May 1, 2007

By L. Torres, C. S. R. Rondestvedt, M. Bustos

In February 2010, Teck’s newest Concentrator at Mina Carmen de Andacollo (CDA), Andacollo, Chile was commissioned. The Concentrator is a single line configuration, comprising of one 36 ft diameter x 20 ft long SAG mill driven by an 18,000 hp gearless drive. The SAG mill feeds two ball mills each 25 ft in diameter x 40.5 ft long, each driven by a total of 19,000 hp through dual pinion drives. A series of four phases will be reviewed from operational readiness, mechanical completion, commissioning, and ramp-up. Also, now after 6 months of operation, this paper will review the significant steps taken during ramp-up enabling the announcement of commercial production, in October 2010.

Jan 1, 2012

By J. E. Armstrong

"Pinchi Lake and Bralorne Takla mercury mines; Canada's only producing mercury mines during the past war (1939-1945); occur within the Pinchi Lake mercury belt. This belt is in central British Columbia; and is approximately 150 miles long extending from southeast of Fort St. James northwest to the headwaters of Omineca river.During the field season of 1937 cinnabar was discovered by J. G. Gray of the Geological Survey in Permian limestone on the north shore of Pinchi lake, where the main showings of the Pinchi Lake mercury mine were later developed. Following the publication of Gray's report claims were staked in the spring of 1938, and later that year were optioned to the Consolidated Mining and Smelting Company, and in June 1940 a reduction plant with a rated capacity of SO tons a day was brought into operation. In 1943 the plant had a capacity of more than 1,000 tons a day. The grade of ore treated was reported to average S to 10 pounds of mercury a ton, and production during the years 1940 to 1944 exceeded 4,000,000 pounds. The Bralorne Takla mercury mine, which is 90 miles northwest of the Pinchi Lake mercury mine, was brought into production in November 1943 with completion of a 50-ton mill. During the next 10 months more than 100,000 pounds of mercury were recovered, and the grade of the ore was reported to average 15 to 20 pounds of mercury a ton. During the war, production from these two properties was far in excess of Canadian requirements, and Canada was able to supply the United Kingdom and United States with part of their need.s. Both properties ceased operations during 1944, and, due to an excessive supply of mercury, have not yet reopened. The Pinchi Lake mercury belt lies along a northwest-trending major fault zone called the Pinchi fault zone (Fig. 1). This zone is approximately 150 miles long and varies in width from 200 to 1,000 feet . It forms the northeastern edge of a northwest trending fault belt up to 10 miles or more wide in places. In general the northeastern margin of the Pinchi fault zone represents the contact between closely folded, stratified Permian rock:s on the southwest and Mesozoic formations and Omineca intrusions on the northeast. It seems probable that the fault zone marks the site of major thrust faulting from the southwest and that the Permian rocks moved up with respect to the Mesozoic formations. Intense faulting occurs in the Permian rocks within the fault zone. There the more important faults trend north and northwest, dip steeply west and southwest, and may join a major low-angle thrust fault at depth."

Jan 1, 1954

By Patrick Andrieux

Numerous rock blasting design methodologies have been developed over the years, relating either to the primary objectives of blasting, such as the size distribution of the blasted material, or to its undesirable side effects, such as damage to the remaining rock mass. All existing methodologies, while of use, do have serious shortcomings. The question remains whether further improvements can be achieved in the field of practical rock blasting engineering. One approach that seems to hold promise is the relatively new matrix-based rock engineering systems (RES) methodology. It has been conceptually demonstrated that RES could be efficiently adapted to blasting. A brief overview of rock blasting design techniques and their main shortcomings is followed by the basic concepts governing rock engineering systems and a discussion on their pertinence to blasting. The paper concludes with a review of current efforts to develop a useful practical blast design tool using RES. SOMMAIRE Le potentiel d?application des systèmes d?ingénierie du roc aux tirs à l?explosif. De nombreuses méthodologies de conception d?abattage du roc à l?explosif ont été développées au cours des années, qui ont adressé soit les principaux objectifs des tirs, comme par exemple la granulométrie du matériel dynamité, soit ses effets secondaires indésirables, tels les dommages au massif rocheux. Toutes les méthodes existantes fonctionnent dans une certaine mesure et sont utiles - elles sont cependant pour ainsi dire toutes affectées par des limitations ou défauts plus ou moins sévères. La question demeure quant à savoir si des améliorations supplémentaires peuvent être apportées dans le domaine de la conception pratique des opérations d?abattage du roc à l?explosif. Une approche alternative qui semble prometteuse est celle relativement récente des systèmes matriciels d?ingénierie du roc (?Rock Engineering Systems?, ou RES). Il a été démontré de manière conceptuelle que les RES ont le potentiel d?être adaptés aux opérations de sautage. Une brêve revue des principales techniques de conception des tirs à l?explosif est suivie d?un énoncé des principes de base gouvernant les RES, ainsi que d?une discussion sur leur pertinence aux opérations de tir. Cet article conclut avec la revue d?un projet de recherche axé vers le développement d?une méthodologie de conception des tirs à l?explosif basée sur les RES.

May 1, 2002

By J. Oliver, B. Wilson, 10

"Red Dog is one of the world’s largest zinc producing mines and a significant producer of lead and silver. While some of the operational challenges relate to the mine’s location in a remote part of Alaska, there are also challenges in the mineral separation process. Recent processing upgrades have included the installation of two M5000 IsaMills to improve the zinc regrind circuit and of one Jameson Cell to improve the pre-flotation circuit. Relatively fine grinding is required to achieve efficient mineral separation at Red Dog, but while fine grinding aids in the production of high grade concentrates, it also creates challenges in the efficient recovery of fine minerals. Over half of the lead lost to the lead circuit tailings, as well as almost half of the zinc lost to the final tailings, is in the finer size fractions (<10 µm). The high pulp density experienced in the pre-flotation and lead rougher circuits also causes significant entrainment loss of lead and zinc to the pre-flotation concentrate and of zinc to the lead concentrate. To help improve fine mineral recovery, Red Dog has recently plant tested and installed magnetic conditioning technology in the flotation circuits. The equipment aggregates fine paramagnetic sulphides and selectively increases their flotation recovery. This paper outlines the testing and positive results at Red Dog.INTRODUCTIONRed Dog is the largest zinc mine in North America and represents approximately 29% of North American zinc concentrate production. The mine is located in northwest Alaska, approximately 100 miles north of the Arctic Circle and 50 miles inland from the Chukchi Sea. The remote location makes the mine accessible only by air or seasonally by ocean-going barges. Red Dog is a partnership between NANA Regional Corporation Inc, the land owner and Teck Alaska Incorporated, the operator of the mine. Red Dog Ore and Mineralogy The Red Dog deposit is a rich sedimentary exhalative (sedex) zinc-lead-silver deposit. The main minerals present in order of abundance are: quartz, sphalerite, pyrite, barite and galena. Production began in 1989 with mining of the Main deposit. Between 1989 and 2012, approximately 55.6 million tonnes of ore with an average grade of 20.5% Zn, 5.6% Pb, and 97 g/t Ag was mined from the Main deposit. Subsequent to the development of the Main pit reserve, two additional open pit deposits were discovered: Aqqaluk and Qanaiyaq. The first blast in Aqqaluk occurred on June 4, 2010. As of December 31, 2014, the Aqqaluk deposit reserve is an estimated 45.7 million tonnes of ore with an average grade of 15.1% Zn, 3.9% Pb and 71 g/t Ag."

Jan 1, 2016

By M. P. Rennick, D. M. Burton

The Murray Brook massive sulfide deposit, which was the first geochemical discovery in the Bathurst camp, is one of the largest sulfide deposits in the area. The massive sulfides are hosted by quartzose metasedimentary rocks in the lower part of the Ordovician Tetagouche Group. This thick succession of sedimentary rocks is overlain conformably by felsic volcanic rocks, and is structurally overlain by mafic volcanic rocks. The massive-sulfide body is polydeformed, but primary metal zoning is still discernable and may permit future exploitation of discrete lead-zinc and copper zones. Although it was discovered in 1956, the deposit was not developed until 1989, when Murray Brook Resources commenced processing of gossan containing precious metals. Recovery of gold, silver, and mercury is accomplished by indoor vat leaching on a year-round basis.

Jan 1, 1992

By K. D. A. Whaley

The Captain North Extension deposit consists of five sulfide lenses hosted in cherty and chloritic metasediment that is bounded by quartz-eye rhyolite and laminated rhyolite. Lens 2 consists of sphalerite and galena with silver-rich tetrahedrite in chert. Lens 3 contains massive pyrite, with chalcopyrite and minor gold, gradational to minor pyrite in a chloritic metasediment. The other lenses are unexplored. The sulfides occur as beds, fracture infills, and disseminated grains. Reserves are estimated at 207 555 tonnes grading 7.380/0 Zn, 2.76% Pb, and 91.81 g/t Ag. The deposit is isoclinally folded, dips steeply west, plunges 50 degrees south, and is faulted out to the north, where drag folding has reversed the plunge. Minor cross-faults contain talc and sericite. High sphalerite but low pyrite abundances result in poor responses to standard electromagnetic techniques. Lens 3, which contains more pyrite than Lens 2, responds better to induced polarization and allows detection. Geochemical anomalies are found in a nearby swamp and stream, but an impervious till cover inhibits the development of soil anomalies.

Jan 1, 1992

By M. J. Michaud, M. J. Lavigne

"Abstract - North American Palladium Ltd. operates its Lac des Iles open pit palladium mine 85 km north of the city of Thunder Bay, Ontario. The Roby Zone deposit occurs within the mafic/ultramafic Lac des Iles Intrusive Complex (LDI-IC), which was created by multiple pulses of magma of varying composition within several closely spaced chambers. Chaotic lithological distribution, the presence of magmatic breccias, and the rarity of rhythmic layering suggest a dynamic intrusive environment with disruptive magma pulses. As of December 31, 2001, measured and indicated resources for the 950 m long by 815 m wide Roby Zone deposit totalled 159 Mt grading 1.55 g/t Pd, 0.17 g/t Pt, 0.12 g/t Au, 0.05% Cu, and 0.05% Ni at a palladium cut-off grade of 0.7 g/t. The Roby Zone contains an additional 73 Mt of inferred resources at similar grades.The Roby Zone is dominated by varitextured gabbro containing pipes and pods of breccia, and large blocks (~60 m across) of varying lithology. Mineralization at Lac des Iles occurs as: (1) a PGEand base metal-rich magmatic matrix of breccia (breccia ore); (2) mineralized dikes or sills (gabbronorite in North Roby ore); (3) lower-grade mineralization in varitextured units that are host to the distinctive breccia ore and envelope the North Roby ore; and (4) high-grade mineralization associated with strong silicate alteration exemplified by high-grade ore.The close spatial association of the mineralized breccias with both varitextured units and silicate alteration leads to an interpretation that the energetic magma that created breccia was charged with a dissolved fluid, and that this deuteric fluid exsolved at high temperatures to migrate through crystal mush, enhancing crystallization along its pathways, resulting in variable grain size. This transformation occurred at high temperature and produced sulfide-poor, varitextured gabbro-hosted mineralization exemplified by some of the mineralization in the North Roby Zone, and also found throughout the Roby Zone. The association of hydrous silicate alteration with mineralization can be explained by continuing fluid migration during cooling and continued metal transport. Résumé - North American Palladium Ltd. opère la mine à ciel ouvert de Lac des Iles située à 85 km au nord de Thunder Bay, Ontario. Le gisement Roby Zone est encaissé dans le complexe mafique/ultramafique de Lac des Iles (LDI-IC), lequel représente une intrusion polyphasée créée par plusieurs pulses magmatiques de différente composition à l’intérieur de chambres magmatiques fermés. La distribution chaotique des lithologies, la présence de brèches magmatiques, et la quasi-absence de litage rythmique suggèrent un environnement magmatique dynamique perturbé par l’introduction de nouveau magma. Au 31 décembre 2001, les ressources mesurées et indiquées s’élevaient à 159 millions de tonnes titrant 1,55 g/t Pd, 0,17 g/t Pt, 0,12 g/t Au, 0,05% Cu, et 0,05% Ni, pour une teneur de coupure de 0,7 g/t Pd. De plus, la Roby Zone contient 73 millions de tonnes de ressources inférées à une teneur similaire.La Roby Zone est principalement encaissée dans un gabbro de texture hétérogène (varitextured) caractérisé par des cheminées et des lentilles de brèches et des énormes blocs (environ 60 m de diamètre) de plusieurs lithologies. Au Lac des Iles, la minéralisation en EGP et en métaux de base se retrouve dans la matrice magmatique de brèches (breccia ore), dans des dykes ou des sills minéralisés (gabbronorite dans la zone North Roby ore), comme minerai de basse teneur encaissant le minerai de brèche (breccia ore) et enveloppant la zone North Roby. Du minerai de haute teneur est également associé avec une forte altération en silicates dans la zone high-grade ore.L’étroite association spatiale entre les brèches minéralisées et les unités de texture variée (varitextured) et l’altération en silicate suggère que le magma énergique qui a causé la bréchification était chargé de fluides. Ces fluides deutérique"

Jan 1, 2001

By H. R. Kempthorne

"The Property of Bevcon Mines Limited, including a recently acquired adjoining south group, occupies an area of 2,625 acres in northeast Louvicourt township, Abitibi county, Quebec. It is situated 17 miles east of Val d'Or at the junction of provincial highways 58 and 59.Gold was first discovered in the area in 1931 by the late S. B. Jowsey on the present property of Buffaddison Gold Mines adjoining to the west. However, it was not until the winter of 1944-45 that diamond drilling encountered encouraging results on the Bevcon claims. During the period 1946-1948 a shaft was sunk to 1,000 feet and considerable development undertaken from the 500-foot to the 1,000-foot levels. Between 1947 and 1950 approximately 24,000 tons of dump ore and 48,000 tons of ore by stoping were milled at Perron Gold Mines. The favourable results of these tests prompted the decision to construct a milling plant at Bevcon. The mill began operating in July 1952, and presently has a capacity of 800 tons per day. In 1953 the shaft was deepened to 1,600 feet and is currently (1955) being driven to 2,225 feet.Total production of gold to the end of 1954 has been 101,024 ounces from the milling of 697,427 tons of ore of an average grade of 0·163 ounces per ton.GeologyThe Bevcon orebodies occur in a granodiorite stock which has an east-west length of approximately 4 miles and a maximum width of 1 1/2 miles. The property covers the central portion of the stock and its contacts with the Keewatin volcanics. Approximately one-third of the northern contact and one-half of the southern contact are contained within the Bevcon claims. The granodiorite has been cut by acid (feldspar porphyry) and basic dykes trending east-west. A younger diabase dyke, 300 feet wide, strikes northeasterly across the property 1,000 feet east of the shaft.The main ore zone, striking east-west, lies between the more northerly porphyry dyke and the north granodiorite-greenstone contact. It has been extensively sheared, fractured, altered, and mineralized by gold-bearing solutions. It is approximately 2,000 feet Jong from the west boundary towards the diabase dyke. The shaft is centrally located and passes through the south contact of the ore zone at the 500-foot level. The zone increases in width and trends northerly with depth, due to the porphyry and greenstone contacts having average dips of 80 degrees and 70 degrees respectively to the north. Thus on the uppermost or 500-foot level the width is 150 to 200 feet, and at the present bottom level at 1,600 feet the width is 400 to 500 feet.Another gold-bearing zone has been indicated 200 to 400 feet south of the main ore zone by limited surface drilling."

Jan 1, 1949

By Mohammed Rachek

Résumé : la mine d?Elhammam, opération du groupe minier Marocain Managem, est située au sud de la ville de Meknes à 63 km, elle exploite un gisement de fluorine depuis 1974. La minéralisation se présente sous forme de deux filons principaux orientés N45° avec un pendage variant de 65 à 90° NW, entre ces deux filons on note la présence d?une succession de filons satellites sécants. La méthode d?exploitation pratiquée depuis le démarrage de la mine est celle des chambres magasins, elle assure une cadence d?extraction annuelle de 250000 tonnes. Cette méthode favorisée par une très bonne compétence mécanique des épontes de la minéralisation a offert à l?exploitation une rentabilité très satisfaisante grâce à son faible coût mine. Les travaux de recherche géologique menés en parallèle à l?exploitation ont permis la découverte d?un nouveau secteur ?K-Est Gouaïda? (KEG) qui fait l?extension nord-est du gisement principal, la minéralisation de ce secteur se présente sous forme de deux filons très étendus latéralement (900 m d?extension) et présentant une puissance minéralisée irrégulière et très faible 1.2 m en moyenne, les épontes de la minéralisation sont constituées de schistes de qualité mécanique très faible. Vers la fin des années 1990, l?exploitation s?est orientée vers le développement minier du secteur KEG. Ce développement consiste à faire le choix adéquat de la méthode et de l?infrastructure minière pour l?exploitation de ce nouveau secteur, KEG. La méthode des chambres magasins, pratiquée dans le gisement principal avec un faible coût mine, n?est pas praticable dans le nouveau secteur à cause de la qualité de ses terrains, l?irrégularité de la morphologie de sa minéralisation et de la faible puissance des ses filons. Seule la méthode des tranches montantes remblayées (TMR) peut être applicable techniquement vu les spécifications suscitées de la nouvelle minéralisation, la TMR doit être appliquée sous sa variante mécanisée pour faire face au niveau exigé de la production. Après le pilotage de l?exploitation par TMR mécanisée dans le secteur KEG, il a été confirmé que cette méthode donne une grande satisfaction en matière de stabilité des terrains, sécurité, sélectivité, productivité et récupération du gisement, néanmoins elle reste pénalisée par un coût mine trop élevé pour garder le niveau de rentabilité recherché par l?exploitation d?un produit de faible valeur marchande telle que la fluorine. Dans l?objectif de rentabiliser l?exploitation du secteur KEG qui représente en réserves l?équivalent d?une durée de vie de 4 à 5 ans et d?assurer la pérennité de l?activité, l?exploitation en collaboration avec Reminex, la filiale d?ingénierie de Managem, a adapté une nouvelle variante de la TMR mécanisée dite TMR avec plan incliné sur remblai. Cette nouvelle variante de la TMR consiste à réduire au maximum les travaux dans le stérile en reconstituant un plan incliné sur le remblai à l?intérieur des filons pour faire évoluer en vertical l?exploitation des tranches en montant vers la tête d?un panneau de minerai. La variante des tranches montantes remblayées mécanisées avec plan incliné sur remblai a été imaginée et appliquer en 1978 dans la mine de fluorine de Burc située au Sud-Ouest de la France (Sicard et Mailloux, 1983). Imaginée pour une cadence annuelle de 30000 tonnes et une mécanisation très modérée cette variante a été adaptée par l?exploitation de la mine d?Elhammam en 2002 pour un haut degré de mécanisation et une cadence d?extraction annuelle de 250000 tonnes de minerai. Cette variante de la TMR est appliquée depuis le début de 2003 dans les chantiers du secteur KEG, elle présente les mêmes avantages techniques que la TMR mécanisée classique et elle a permis la réduction du volume des travaux d?infrastructure de 17.65 m à 6.25 m de travaux par 1000 tonnes de minerai. Ceci s?est traduit par une baisse du coût technique de la mine de 34% ce qui a donné un nouveau souffle à la mine pour assurer sa production et pour poursuivre la recherche géologique d?éventuelles zones à mettre en valeur.

Oct 1, 2004

By P. R. A. Andrews

"Garnet occurs in schists and gneisses in all provinces of Canada, all mainly in Quebec and Ontario. There is currently a renewed interest in exploration for economic sources of garnet for abrasive applications because of the inherent dangers from exposure to ground silica from sandblasting operations.High-quality garnet is used for lapping and grinding of glass and ceramics; for coated and bonded products such as sandpaper and cloth; and abrasive wheels for grinding and finishing various metals, woods, rubber and plastics. Low-quality garnet is used for cleaning and conditioning aluminum and other soft mewls, particularly by aircraft manufactures. Garnet may be added to grouting cements for oil-well drilling applications, and it has also been used for low- to medium-level radiation shielding. Garnet has been studied extensively by CANMET and its predecessor, Mines Branch, between 1917 and 1990. Twenty-nine studies relating 10 various aspects of beneficiation are presented and a review of the more important studies is presented. The information includes mineralogy, beneficiation methods, product sizes and analyses."

Jan 1, 1995

"The gravimetric dust sampler is one of the tools now available to the industrial hygienists for determining the worker &apos;s exposure to the numerous types of particulate matter that may be present in the workplace. The paper &apos; reviews the different sampling trains that can be used for the two major criteria for respirable dust and some of the sources of error in this dust assessment technique.IntroductionIt may be stated simply that the measurement of airborne dust in the working environment is done for one or two reasons: namely, for engineering control purposes and! or to evaluate the potential for toxicological insult arising from the inhalation of dust particles.This paper reviews the progress made in the development of dust-assessing instruments, particularly the gravimetric types designed to meet British and U.S. dust criteria , and discusses the limitations in their use for this purpose."

Jan 1, 1981

By Marcel M. Djivre

The paper will outline historically the different materials used for pouring sockets and illustrate the current trend due to inherent advantages. A section will be devoted to engineering stress analysis showing the criteria necessary for the wires not to slip inside the poured socket material. The Ontario Mining Regulations pertaining to poured sockets will be reviewed with emphasis on the acceptable type of sockets depending on usage. In addition the paper will review the proper socket preparation techniques and explain the destructive testing conducted at the Materials Testing Lab essential for the certification requirements. In conclusion the paper will show the importance of the Certification Program for the safety of Miners working in Ontario, Canada and the World. The paper is also intended to inform the Mine Operators and Consultants that to-date the .Wirelock. sockets have been used safely for hoist ropes of locked coil and non-rotating construction and for the termination of balance ropes, and that further research is required on the construction of a socket approved for rotating type mine hoist ropes.

May 1, 2003

By Laxman M. Amaratunga

"The fine fraction of tailings is usually excluded from the backfill process and generally disposed on the surface in tailings ponds. Because of the ever increasing demand for fine grinding in the extraction process for improved liberation of valuables in the ore, increased production of fines in the tailings has resulted. The negative impact of surface impoundment of tailings on the environment is well known. Amaratunga and Annor (1989) first presented a concept of fine tailings agglomeration for backfill.This paper presents the development of the novel cold-bond tailings agglomeration (CBTA) technology for non-reactive fine gold mill tailings. For cold-bond agglomeration regular portland cement was used as a binder. In order to cut costs, alternate binders such as lime, and blast furnace slag cement were examined. The effects of binder dosage, curing time, and agglomerate size on the fracture load strength of the agglomerate were studied.Fine tailings agglomerates are mixed with coarse tailings or non-agglomerated fine tailings to make high density fill compositions to be used as underground backfill. Alternatively, the agglomerates can be used as aggregates for surface applications. The paper discusses the environmental and operational benefits of this total tailings utilization and disposal technology.IntroductionIn Canadian mines, mill tailings are probably the most commonly used material for backfill. However, only the coarse fraction of tailings is desirable for use as hydraulic fill or high density fills. The fines are disposed on the surface in tailings ponds since they are unsuitable for underground backfilling owing to the following factors:i) slow settling ratesii) longer percolation timeiii) excessive consumption of binder due to drainageiv) poor compactionFor improved value liberation more milling operations have resolved to fine grinding in their comminution circuits. Gold milling operations driven by down stream leaching processes grind their ores excessively fine. In general, gold mines use hardly any tailings for backfilling. This can result in periodic short falls and the need to search for alternate backfill material from other sources. Apparently, the gold producers are the most identifiable sector which suffer from a shortage of backfill materials ( Amaratunga and Annor, 1989)."

Jan 1, 1994

By Akira Miura, Katsuyuki Sato, Yuken Fukano

JX Nippon Mining and Metals Corporation has developed the JX Iodine Process, which is an innovative and patented copper-leaching process for low-grade primary sulfide ores. This process consists of the irrigation of ferric iron and a low concentration of iodide solutions. One-meter column leaching tests were conducted on ore samples from two different mines. At the end of experiments, the total copper recovery exceeded 70% for Sample A and 50% for Sample B with the iodine method, which was significantly higher than that with conventional ferric leaching of 14% for Sample A and 20% for Sample B. To elucidate the reason for the JX Iodine Process effectiveness, cross sections of leached residues were studied. Reaction products were confirmed around chalcopyrite even in the central area of particles in Sample A, however, reaction products were recognized at a depth of only 1 mm from the ore rim in Sample The resistance of Sample A to the leachate appeared to be lower than that of Sample B because Sample A had a high permeability and porosity, whereas Sample B had been affected strongly by a potassium alteration. No reaction products were visible on conventional leaching samples, even at the ore surfaces. INTRODUCTION Hydrometallurgical copper leaching (heap leaching or dump leaching) has been used extensively for copper recovery from oxide and secondary-sulfide ores, but not for primary copper sulfides, which contain mainly chalcopyrite as copper minerals. Although they are major resources of copper, primary copper sulfides are difficult to process because of their refractory nature. Extensive leaching studies have been carried out to leach primary copper sulfides (chalcopyrite), including biological and chemical, using a variety of oxidants and additives to enhance copper recovery. Watling (2013) reviewed acid-chloride-oxidizing agents with chalcopyrite. Abdollahi et al. (2015) tested silver as a catalyst for bioleaching with a chalcopyrite-bearing molybdenite concentrate. Hiroyoshi, Miki, Hirajima and Tsunekawa (2000) found a specific redox-potential zone for high-speed chalcopyrite leaching by controlling the ratio of ferric and ferrous iron. However, no ambient-temperature economic process has been developed for leaching primary copper sulfide, which usually has a low copper grade.

Jan 1, 2019