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By John F. Kearney

Labrador Iron Mines (?LIM?) Schefferville Projects consist of 20 major DSO deposits lying along a 120 km strike length in both the provinces of Newfoundland and Labrador and in Quebec. The town of Schefferville, Quebec lies close to the middle of this 120 km strike. LIM?s various properties comprise twenty different iron ore deposits which were part of the original Iron Ore Company of Canada (?IOC?) direct shipping Schefferville operations conducted from 1954 to 1982 and formed part of the 250 million tons of historical reserves and resources previously identified by IOC. LIM intends to develop all these resources in five separate stages. The first four stages will see the various deposits treated in three beneficiation plants, to be built adjacent to several of the deposits that comprise the Central, South Central and North Central Zones. The final stage is not yet planned but will likely involve a fourth plant. A Feasibility Study has not been completed on any of these Projects. LIM plans the development and mining of the various deposits in separate Stages. It should be noted that only the James and Redmond deposits have been permitted. All other deposits require environmental assessment and permitting. Only the James and Redmond deposits have been subject to detailed mine design. The Houston deposit has had preliminary mine design carried out. All other deposits will require detailed mine design when further geological data is collected and compiled. Detailed metallurgical testwork has been carried out on blue ore from James, Houston, Redmond and Knob deposits and to a more limited extent on yellow and red ores from these deposits. Only limited review work has been carried out on the high-silica blue ores. All of this work will be needed to be complete to confirm the final process routes. Additionally some metallurgical work will be required to be conducted on each of the other deposits to characterize their metallurgical response and to confirm expected recovery levels. Detailed mine design and metallurgical testwork has been carried out on those deposits that will form the basis of production for the initial years but further exploration, testwork and design is required for all the remaining resources. The first plant at Silver Yards and mine construction at James are now complete and initial production is expected in the spring of 2011. Metallurgical testing of the first stage deposits has established that the ore can be successfully upgraded to marketable standards. Based on the current testwork, a program of plant enhancement on the Silver Yards plant is now planned with the objective to increase both the plant throughput and recovery. Production of direct shipping lump ore and sinter fines is forecast at around 1.5 million tonnes in 2011 and, based on current and historical resources, growing to approximately 5 million tonnes in 2015 and thereafter. Production from the first four stages is expected to continue at about this rate through to about 2028.

May 1, 2011

By M. B. Greyver

The results of laboratory tests on iron precipitation from non-decopperized nickel anolyte are discussed. The parameters (pH, oxygen consumption and stirring speed) for iron precipitation from the anolyte, using the oxygen in the air, were determined. In the experiments conducted under optimized conditions, the residual concentration of iron in the anolyte after precipitation was 0.7-2.7 mg/L, and the copper and nickel losses to the solid phase were 0.05-0.07% and 0.05-0.16%, respectively. The filtration ability of the iron slurry obtained was 2 to 5 times higher as compared to that after chlorine oxidation and oxyhydrolysis. The leaching of the non-ferrous metals from the iron cake made using the separate nickel anolyte purification process was possible by dissolution in sulphuric acid. It was established that after cobalt precipitation from the copper- and iron-depleted anolyte, the precipitates obtained had lower ratios of Fe:Co and Ni:Co.

Jan 1, 2006

By Stephen Hardcastle

Presentation Outline ? Introduction ? Mine Ventilation Facts ? Ventilation-on-demand (VOD) ? Sensors/Controls ? Continuing Work ? Conclusions ? Mine ventilation engineering practices were published in 1556 in Agricola?s De Re Metallica (wind sails, bellows, etc.) That was then? This is today? Large fan installations handling >1M cfm

Nov 1, 2011

By Ashley Tews

In 2005, we automated a forklift-based Hot Metal Carrier to be capable of typical metal transfer operations around a smelter. The project was highly successful and the vehicle has demonstrated hundreds of hours of live autonomous operations to thousands of people from industry and the public. As a result of the exposure and success of the project, we have expanded its focus to demonstrate how various technology components can be utilised to gain benefits in other areas of industrial operations. These include asset tracking, vehicle usage analysis, pedestrian detection and infrastructure profiling. Each of these components was derived from the core autonomous vehicle technology suite and has shown a high potential for improving safety and efficiency of vehicle-related operations, and improved diagnostic processes for measuring deformations of bakes and furnaces. The autonomous vehicle project and its extended technologies are described in this paper.

Aug 1, 2013

By A. G. Slade

"This paper deals with the direct application of rock mechanics in the underground mines at the Sudbury Operations of Falconbridge Nickel Mines Ltd. It covers mining methods, the use of photoelastic models, the fore-casting of rock strains and their elimination, closure methods and other common methods of ground control.INTRODUCTIONROCK MECHANICS IS A STUDY IN ROCK BEHAVIOUR and, although it is being termed a new science, it has been practiced since the industry began. Every person involved with rock excavations, from the mine superintendent to the stope driller, is actually practising rock mechanics. They probably call it by another name -experience, and applications of this knowledge are in evidence throughout the Falconbridge operations. Only in recent years have formal rock mechanics studies been employed to provide technical assistance to the mine operators in their primary objective of producing ore safely."

Jan 1, 1968

By Shek N. Lau, Nicola Samman

"Enclosed gear cases on board heavy mining equipment have traditionally been lubricated with regular heavy duty gear oils. However, equipment manufacturers, have recommended the use of an ISO-1000 gear oil for this application to ensure adequate lubricant film strength, especially at the higher end of the working temperature range. The majority of these ISO-1000 gear oils are based either on residual/asphaltic oil or synthetics, primarily higher viscosity polyalphaolefins. Although the performance of these lubricants has been satisfactory, they suffered other shortcomings that equipment users have lived with over the years.The major requirement at the user’s mine was to provide lubrication for the shovel Hoist gear case. Within such a gear case design, the gears and the roller bearings, that have different lubrication requirements, are lubricated with the same lubricant. Several lubricants were used, light gear oils as well as the recommended ISO-1000 heavy gear oils. On the one hand, the lighter oils performed adequately for the lubrication of the bearings that formed part of the enclosed gear system. These lighter oils did not perform as well for the lubrication of the gears due to their lower viscosities, resulting in shorter gear servicelives.On the other hand, the ISO-1000 gear oils performed well for the lubrication of the gears, but were too viscous to creep into the bearing elements to lubricate them adequately, especially during the cold northern Canadian winters. This resulted in catastrophic bearing failures and secondary damages to the gears.The challenge, then, was to formulate a lubricant which met the 1000 cSt at 40°C viscosity requirement as stipulated by the equipment manufacturer, while satisfactorily lubricating the bearings at the full working temperature range. This was achieved by the development of a semi-fluid grease lubricant, which has proven in field trials to give adequate performance in this application for the lubrication of both the bearings and gears down to -40°C.This product met the equipment manufacturer’s performance criteria and resolved, to a large extent, leakage of the lubricant through seals experienced with the use of conventional and synthetic gear oils.Although the main performance criteria of the fluid was its capability to lubricate the “Hoist” gear case, it was also used during the field trial in other gear cases on board the shovel to test its full capabilities.This unusual alternative lubricant was field tested and evaluated for more than two years. Based on this assessment, the product was reformulated to improve its fluidity, slumpability and the settling of debris/wear metals to the bottom of the gear cases. This reformulated softer grade, a semi-fluid grease, has been performing satisfactorily for more than eight months and is still undergoing longer term assessment."

Jan 1, 1996

By S. Sundararajan, Z. Lin

ABSTRACT Fierce market competition and demand have made it imperative for mining companies to achieve higher productivity and operational efficiency. The selection of the best mining method and equipment combinations will enable companies to meet production and efficiency targets. Continuous mining is increasingly preferred by companies for its high efficiency and low unit costs. We developed simulation models for two continuous mining systems: the continuous surface miner (CSM) system and the at-face slurrying (AFS) system. Considering two different case studies, the paper discusses application of developed models to determine the optimal number of trucks and equipment capacities for the two systems.

Jan 1, 2013

By M. Staite

This paper analyzed the feasibility of converting a 5kW natural gas SOFC power generator system designed to operate on natural gas to be fuelled by methanol. The analysis included laboratory methanol fuel processing experimentation, methanol reformate SOFC cell testing, and SOFC system mass and energy balance modelling. Methanol fuel processing experimentation indicated that theoretical reformate compositions can be achieved for high temperature (600-900°C) methanol steam reforming. A 6% open circuit voltage decrease and a 10% peak power current density decrease between cell operation on humidified hydrogen and methanol reformate was observed. SOFC system mass and energy balance modelling indicated that a natural gas SOFC system can be converted to operate on methanol fuel with minimal (1%) efficiency impacts, however the systems' thermal integration can be impacted.

Jan 1, 2005

By J. R. CAMERON

Gypsum is mined in all Atlantic Provinces except Prince Edward Island. It is generally thought to have been derived from the hydration of anhydrite in areas of minimal drainage. Late Devonian downwarping and crustal oscillation east of the Appalachian fold belt allowed the Windsor Sea to advance and retreat in a depositional trough and deposit about 1,000 m of sediments in Mississippian time, much of which were evaporites. The best areas for further gypsum development are lowland basins such as the Cape Breton Lowlands, the Hillsborough area of New Brunswick and the St. George's Lowlands in Newfoundland, all of which are already sites of gypsum quarries. Nova Scotia's gypsum is mined from the Lower Windsor Group, which is divided into subzones 'A' and 'B'; 'B' provides most of the province's gypsum production. The Atlantic Provinces gypsum industry has markets from the St. Lawrence waterway to the mouth of the Mississippi River.

Jan 1, 1984

By E. Johansson, T. Siren, K. Kemppainen

"As part of the preparations for the design of an underground repository for radioactive waste at Posiva’s Olkiluoto site on the west coast of Finland, there has been considerable site investigation work. Except the extensive surface based investigations, Posiva started in 2004 the construction of an underground characterisation facility termed the ‘ONKALO’. The ONKALO has now been completely excavated to the anticipated repository depth i.e. -430–450 m. The research conducted in the ONKALO gives further information on the bedrock and groundwater conditions of the final disposal site, as well as on the impact of the construction. The ONKALO provides an excellent opportunity to investigate the rock at tunnel scale, to conduct in-situ testing in rock, to develop excavation and final disposal techniques in realistic conditions. The ONKALO has aided in collecting the data needed, supported by a Preliminary Safety Assessment, for the application of the construction license that was submitted in the end of 2012. The target is to begin disposal operations in 2022. According to current plans, the final disposal would end in 2112 and the repository would be sealed up by 2120. The testing in the ONKALO still continues several years. This paper presents the current characterisation and research activities in the ONKALO. INTRODUCTIONAfter the Finnish Government's favourable policy decision in 2001, Posiva Oy, which is an expert organisation responsible for the final disposal of spent nuclear fuel of the owners in Finland, has focused further investigations at the Olkiluoto site, western Finland (Figure 1) and has started in 2004 the construction of an underground facility termed the ‘ONKALO’. The ONKALO is not a nuclear waste repository, but more than just an underground research laboratory URL – it is an underground rock characterisation facility. The ONKALO has now been completely excavated to the anticipated repository depth i.e. -430–450 m. In addition to facilitating bedrock research, the ONKALO also provides an opportunity to develop excavation techniques and final disposal techniques in realistic conditions. Later, the ONKALO facilities can be put into use when building and using the repository. The construction methods and materials have been selected in order not to jeopardise the long-term safety of the repository site. The findings of the ONKALO and other investigations will provide the knowledge needed for an application, supported by a Preliminary Safety Assessment, to construct a final repository for spent nuclear fuel at the site. Posiva has submitted an application for the construction licence for a disposal facility in the end of 2012. The target is to begin disposal operations in 2022 and the repository would be sealed up by 2120."

Jan 1, 2015

By R. V. Kumar, C. Schwandt, S. Subramanian, S. Sampath, S. Vimalnath

Waste waters and industrial effluents containing toxic heavy metals such as Pb, Hg, As and Cr, beyond permissible limits (0.1 ppm, 0.01 ppm, 0.02 ppm and 0.05 ppm, respectively) (WHO, 2011), pose serious threats to the ecosystem, when discharged into the environment. It thus becomes imperative to monitor the concentration of the toxic heavy metals and treat them before discharging. In this study with the above objective in mind, a microbial sensor has been developed using P. aeruginosa cells drop coated onto a carbon paste electrode (CPE) for the detection of Pb(II) ions in aqueous solutions. Detailed biosorption experiments confirmed that complete bioremoval of lead could be achieved using P. aeruginosa cells under optimum conditions of pH and biomass loading. For the electro-analytical determination, the Pb(II) ions were initially preconcentrated on the P. aeruginosa modified CPE, reduced and then anodically detected with oxidation of Pb0 using differential pulse anodic stripping voltammetry (DPASV) technique. All the experiments were carried out in the presence of 0.1 M sodium acetate buffer and KNO3 as background electrolyte. The parameters namely pH, scan rate, biomass loading, deposition potential, deposition time and concentration of Pb(II) ions were optimized for the biomass modified CPE, to obtain maximum voltammetric response. Under the optimized conditions of pH 5.6, scan rate of 0.008 V/s, biomass content of 1.7–1.8×109 cells/mL, deposition potential of –1.2 V, and deposition time of 500 s, the developed microbial sensor showed a linear response for the peak current between 0.5×10-5 M and 1×10-8 M of Pb(II) ions with the R2 value of 0.9979. The lowest limit of detection (LLOD) was determined as 2.4×10-7M of Pb(II) ions (0.05 ppm). The redox mechanisms of Pb(II) ions on the P. aeruginosa modified CPE surface are discussed.

Jan 1, 2016

By S. Nikolic, H. M. Henao

"There is renewed interest in the improvement of existing copper smelting processes and the development of new technologies. It has become clear that further accurate information on slag properties, in particular, on phase equilibria are required in order to optimize these processes. It is in this context that improved experimental research methodologies have been developed specifically to provide information on phase equilibria at the oxygen partial pressures encountered in copper smelting practice. The methodology involves synthetic slag equilibration at controlled gas atmospheres, quenching and measurement of compositions of phases with an electron probe X-ray microanalyser (EPMA) with wavelength dispersive detectors (WDD). Application of modem analytical tools and careful design of experiments greatly improve accuracy of determination of phase equilibria in complex, multi-phase slag systems. New experimental data on phase equilibria for the copper smelting and converting silicate slags at controlled oxygen partial pressures in the temperature range between 1200°C and 1350°C in the ""Fe0""-Ca0-SiO2 system and in the ""Cu20""-""Fe0""-Ca0-Si02 system in equilibrium with metallic copper are reported, and differences between various data sources are analyzed."

Jan 1, 2007

By Ahmad Ghahremaninezhad, Denver H. Cowan

Much of today’s gold is locked within sulphide minerals. These sulphide minerals, including pyrite, need to be subjected to oxidative pre-treatment in order to leach the refractory-gold using traditional methods. Typically autoclaves employing high temperatures between 180?225 ºC, and extremely high pressures between 1,500?3,200 kPa, are used for the oxidative pre-treatment. However, the autoclaves themselves are very expensive, costly to operate and maintain, and produce excess sulphuric acid. This paper studies the atmospheric oxidation of pyrite in ferric sulphate solutions. In general, pyrite oxidation under atmospheric pressure can result in high elemental sulphur production, i.e. less acid generation. Activated carbon has displayed an ability to catalyze the process, achieving reasonable kinetics. The reaction kinetics were investigated by altering acidity of the leaching solution, temperature, catalyst ratio, sparged oxygen and agitation. A combination of X-ray diffraction, scanning electron microscopy, optical microscopy, X-ray fluorescence, inductively coupled plasma mass spectrometry (ICP-MS), and atomic absorption spectroscopy (AAS) were used to monitor the kinetics of the process and elemental sulphur yield. The purpose of this investigation was to determine optimal operating conditions that maximized kinetics of the atmospheric oxidation while maximizing elemental sulphur yield.

Jan 1, 2015

By K. B. Young

Possibly the most complex fatigue problem associated with the development of the axial-flow 'gas turbine is discussed in its broader aspects from the metallurgical viewpoint. Reference is made to nodal patterns, interference diagrams, etc. The use of such data in analysis of a turbine :blade failure is illustrated. Special attention is given to the influence of some metallurgical variables affecting fatigue strength and, in particular, heat treatment is shown to have a pronounced effect on .the relative fatigue and creep strength properties of a nickel-chromium-cobalt base alloy suitable for turbine blade applications.

Jan 1, 1958

By H. M. Woodrooffe

This paper deals with the laboratory facilities at the Mines Branch for carrying out research in the industrial minerals field, and also reviews current programs in ceramics and construction materials, in non-metallic minerals and in the milling of industrial minerals. It then discusses the application of these pro-grams to industrial problems.

Jan 1, 1967

By J. O. Yeboah, V. Boakye, P. A. Bepswa, M. Lombard, G. Nutor

The comminution circuit at Tarkwa Gold Mine was commissioned as a Single Stage SAG mill operated in closed circuit with hydrocyclones designed to process 4Mtpa. The circuit was later expanded by adding a secondary ball mill in closed circuit with hydrocyclones with a view to treat 12Mtpa. The change in the circuit configuration and assigning the low aspect ratio SAG mill for primary grinding application makes the Tarkwa experience unique in terms the optimisation strategy and operating philosophy. This paper reports the findings from a series of surveys performed on this plant. The surveys reported include data obtained when the SAG mill was operated as a single stage mill in closed circuit with hydrocyclones and also SABC mode under two different feed conditions. The differences in operating philosophy between the initial single stage SAG circuit and the current SAG/Ball mill circuit are discussed.

Jan 1, 2012

By M. J. Merwin

Heat treated seamless tubular products are processed in a fashion that can be easily modified to produce dual phase microstructures, through the implementation of intercritical soaking prior to quenching. Dual phase steels are known to possess low yield strength compared to tensile strength. The steel line pipe market is interested in low yield-tensile ratio materials for application in reel barge pipe laying operations. In the current work compositions of commercially produced material already in use for the line pipe market were examined and dual phase microstructures were successfully developed. The microstructure and properties of the materials were found to be stable over the range of intercritical temperatures employed. Tempering temperature and, somewhat unexpectedly, small chemistry differences were found to have the largest influence on properties. Excellent toughness performance was observed in samples tempered at temperatures in excess of 550°C. Tempering in this temperature regime produced materials with strength suitable for application as API X60 line pipe. A difference in tensile strength between steels of similar chemistry was observed, and is not fully understood at this time. Welding performance was considered through simulation of three regions of the heat-affected zone. Neither intercritical temperature, nor tempering temperature, were found to have a significant influence on the heat-affected zone properties. The peak temperature achieved in the thermal cycle was the only significant factor. The hardness of the heat-affected zone was found to increase continuously with increasing peak temperature. While toughness was found to be low for both partially-transformed and coarse-grain heat-affected zones, the toughness of the fine-grained heat-affected zone was substantially better. Based on the results found in this laboratory study, a limited production trial is expected.

Jan 1, 2005

By J. M. D. Wilson, W. Petruk, C. Coté

"The behaviour of minerals in the Mount Wright spiral circuit was investigated to find methods of improving iron oxide mineral liberation and recovery. The feeds, concentrates and tailings from rougher, cleaner and recleaner spirals in one mill line were sampled before and after the sizing screen openings were reduced from 2 mm to 1.6 mm. Sized fractions of each sample were analyzed with the MP-SEM-IPS image analysis system at CANMET to determine mineral quantities and liberation characteristics of the iron oxide minerals. Mass balance techniques were used to calculate stream recoveries of iron, silica, total iron oxide minerals, hema¬tite, goethite, quartz, ferromagnesian silicates, and liberated and locked total iron oxide minerals for each sieve fraction.The reduction of the sizing screen openings increased the ap¬parent liberation of the total iron oxide minerals in the screen undersize from 89% to 94% and raised the over-all iron recovery from 84.4% to 85.3%. Apparent liberation of iron oxide minerals in the cleaner sand also increased from 70% to 85%, but the – 75 µm fraction re¬mained the only fraction containing an acceptable amount of liber¬ated iron oxide minerals in each case. Due to limitations of spiral and grinding efficiency it is recommended that the cleaner sand be screened at 300 m, the +300 m fraction be reground, and the – 300 p.m fraction be rerouted to the rougher spirals.The amount of fine liberated iron oxide minerals (– 106 m) lost in the tailings was 46 TPH in mill line 3. This value represents 41 wt % of the free fine iron oxide minerals, or 7 wt % of the total iron oxide minerals in the spiral feed. Further work is needed to investigate the possibility of recovering this material by other methods.Middling iron particles (010 50%) and presumably free gangue in the size range –300+ 75 m tend to be recovered by spirals by entrapment."

Jan 1, 1990

By Wael Abdellah

Mine haulage drifts are the primary access to the mining blocks of an orebody in a multilevel mining system of a tabular ore deposit. The stability and functionality of haulage drifts are thus crucial to the success of a mining operation. Drift instability could lead to serious consequences such as injuries, production delays and higher operational cost. In this paper, the performance of the haulage drift stability is evaluated on the basis of the primary rock support system comprising 1.8 m resin grouted rebars in the drift walls and 2.1 m long bolt in the back. Two failure criteria namely the extent of Mohr-Coulomb yield zones around the drift, and linear elastic brittle shear failure are adopted and compared, with respect to lower level and same-level mining and filling sequence in the vicinity of the haulage drift. The case study is one of the #1 Shear East zone of the Garson Mine in Sudbury, Ontario. Random Monte Carlo (RMC) technique, which has been previously established to assess the haulage drift stability, is employed in this investigation. The RMC technique is used in conjunction with finite difference modelling software FLAC for random assignment of model input parameters in the FLAC grid. Deterministic model results reveal the drift behaviour in terms of deformation (convergence) and mining-induced stress distribution. Comparison between the two different criteria is carried out to determine which method is most suitable in evaluating unsatisfactory drift performance. The results are presented in terms of probability of instability and categorized with respect to failure condition and mining step. It is shown that the brittle shear failure condition based on linear elastic response calls for enhanced support system at a later mining step than what Mohr- Coulomb yielding condition does. The paper presents a detailed discussion of the stochastic analysis results.

Jun 1, 2012

By Claude Hubert, Robert Sansfaçon

"The Malartic gold camp includes the Malartic Gold Fields, Barnat, East-Malartic, Canadian Malartic and Sladen mines. From 1935 to 1984, these mines have yielded 212 403 kg of gold. They occur within a 900 m wide belt of highly sheared, dislocated and faulted volcanic and sedimentary rocks (Piché and part of the Pontiac groups) herein named the Malartic Tectonic Znne (MTZ). The zone trends WNW-ESE and separates two lithotectonic sedimentary domains, the Cadillac to the north and the Pontiac to the south. The sedimentary domains are characterized by their coherent fold generations consisting of open to tight reclined and recumbent F1 folds that have been refolded into series of asymmetric upright F2 folds. A flat-lying schistosity (S1 ) and a vertical pressure-solution cleavage (S2) are ubiquitous throughout. Discrete sets of brittle and brittleductile faults are synchronous and parallel to each of these two fabrics.The MTZ trends N320° in the northwestern sector of the town of Malartie, changing to N2800 at its easternmost extremity. The Malartie and Sladen faults constitute its northern and southern boundaries respectively. These two faults also bound another set of faults oriented N305°. Throughout the MTZ, the faults at N280° and N320° and those at N305° outline a series of anastomosed motifs that constitute the principal structural feature of the Malartic district. Locally, a fourth set of minor faults at N065° combines with the other three prominent sets. All these faults have disrupted the gold-bearing volcanic, sedimentary and intrusive rocks encountered throughout the MTZ.The MTZ comprises numerous lozenge-shaped blocks of komatiites and basalts or greywackes and black shales which are cut by disjointed dikes, sills and small intrusions of felsic and mafic rocks. The latter includes gabbro, diorite, lamprophyre, monzonite and pegmatite. They frequently fill conjugate sets of fractures. In some areas, they are clustered into coalescent intrusions. The present morphology of these intrusive bodies( cube, chocolate-tablet boudin, parallel epiped and cigar) is not representative of their primary forms but the result of late shearing and faulting indicative of a major tectonic event subsequent to their emplacement. The intrusions were injected during a brittle stage of deformation related to the F1 folding but prior to the development of the F2 folds and subsequent tearing and shearing by late brittle and brittle-ductile faults . The ultramafic and mafic rocks are intensely altered to serpentine, tremolite, actinolite, carbonate, biotite, hematite and pyrite according to the nature of their proto/it h. In the vicinity of the MTZ, all lithologies exhibit mineral assemblages indicative of the upper greenschist or lower amphibolite facies of metamorphism.The structural evolution of the MTZ involved superimposed folding, shearing, transposition, mylonitization, brittle and brittle-ductile faulting. Each lenticular motif results from the combined effect of conjugate sets of shear zones that outline lozenge-shaped blocks where strain markers indicate different strain states from cores to margins. Bedding in ultramafic flows and/or sedimentary rocks is either NW-SE or NE-SW within the blocks but, in the vicinity of the Malartie and S laden faults, it has been rotated to become subparallel to the faults.Ore shoots are most commonly associated with altered and deformed bodies of diorite and monzonite, or some mafic and ultramafic schists and, at the Canadian Malartic, Sladen and East Malartic mines, with metasedimentary rocks. The shoots occur in close proximity to the various faults of the MTZ but the gold itself is intimately associated with pyrite, biotite and carbonate in halos bordering fractures crisscrossing the different host rocks. The density of fractures and the width of their altered zones have been significant parameters in the production of economic ore shoots. Grains of gold are visible in some veins of quartz a"

Jan 1, 1990