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By K. J. G Hedges

"Once a health based guidance limits for exposure to diesel exhaust have been established, and as part of a multi-disciplinary team, the program for exposure reduction should incorporate the plan-do-check-adjust cycle. Setting a suitably protective (health based) occupational exposure limit (OEL) for diesel particulate matter (DPM) and nitrogen dioxide is a key driver to reduce exposure. It is important to go beyond regulations and reduce exposure to diesel exhaust, DPM, as low as reasonably achievable (ALARA) such as that prescribed under the Australia, Queensland Mining and Quarrying Safety and Health Regulation 2017 where under section 135 Limiting workers exposure, the workers exposure must not exceed the exposure limit applying to the worker for the hazard; and is ALARA. It appears that previously acceptable OELs are no longer safe. Therefore it is important that the internal responsibility system be implemented and the precautionary principle approach be followed, especially as it may be some time before a suitably protective OEL specifically for DPM is in place. One leading multi-national mining company BHP Billiton has acknowledged a significant lag that exists between regulatory action and the level of science that informs health risk. This company is managing exposure to diesel exhaust to as low as technically feasible. This same company that has set an interim target for managing diesel exhaust to 0.03 mg/m3 is achieving these levels which paves the way for other mining companies and general industry including construction. The Occupational Cancer Research Centre 2017 recommends reducing personal exposure to within 0.02 mg/m3 (EC) for underground mining and 0.005 mg/m3 for other workplaces. Controlling DPM is important to prevent cancer however it is also important that that nitrogen dioxide (NO2) be reduced (ALARA) and that careful selection of control technology be considered such as the proper selection of a diesel oxidation catalyst so that the level of NO2 does not in fact increase. The example from BHP Billiton provides a leading practice including using a multi-disciplinary approach and the importance of controlling emission at source and having an auditable diesel emissions based monitoring program in place."

Jan 1, 2019

"THE CONCEPT of energy as a commodity, while not entirely new, is not as widespread as the importance of the idea to this modern world would lead one to expect. The growth in the supply and use of energy over the past years has been tremendous, but our very closeness and familiarity have somewhat distorted the viewpoint, particularly of the younger generation. To many of us who remember the wonderful satisfaction of our first responsibility for directing two horsepower hitched to a farm cart or hay wagon, there still arises a feeling of some awe at the casual flick of the switch with which our sons and daughters summon to their convenience the service of some one hundred or more horsepower.Energy is the vital component of our existence and, no matter what contempt our day-to-day familiarity may •breed, it is wise to .pause from time to time and consider our national energy standing. Have we still capital in the bank? Are our expenditures wisely •conceived and well directed? Is provision being made for the years •ahead for the needs of our children and our children's children?"

Jan 1, 1953

By X. Xu, J. K. -W. Wong, J. -Y. Delenne, K. Soga

Hydraulic fracturing (HF) is a mulit-scale and multi-physics process which makes numerical modelling challenging. Conventional numerical models focus on multi-physics nature of HF but the multiscale nature is compromised by idealization of reservoir to be continuous, homogeneous and isotropic. However, natural fractures take a significant role in the success of HF for exploration of unconventional resources like Shale gas. Advancement in microseismic monitoring provides useful data for simulation in a much greater details. There is an urgent need to develop a suitable numerical tool for multi-scale threedimensional simulation to better understand the roles of discontinuities and heterogeneity in reservoir and its interaction with HF, especially to address the environmental concerns such as induced seismicity. In this paper, a simple discontinuum numerical method – Lattice Element Method (LEM) is proposed to model HF in a large scale three-dimensional model. A reservoir is modelled as a lattice network composed of 1D Hookean’s spring. Fracturing is modelled simply by removing lattices that meet a specified threshold as determined by the critical energy release rate of the rock. By introducing disorder in the model, mesh dependency in modelling fracture growth is minimized. Fluid flow is simplified as flow in pipe network and the permeability of pipe is related to fracture aperture by cubic flow law. Therefore, fracture flow and rock deformation are fully coupled. In this paper, four simulations of the same configuration except with different degrees of reservoir heterogeneity are presented. Fractures formed are diffusive and two groups of fracture are identified – connected fractures and isolated fracture without clear spatial correlation. The former forms a ‘fracture cloud’ and contributes to fluid flow and modeled by pipe network. The flow of fluid is highly tortuous and pipe network is sparely connected. The degree of reservoir heterogeneity controls the growth of ‘fracture cloud’ and pipe network. Microseismic monitoring often shows diffusive fracturing during HF on site and hence the outcome of the proposed model can be compared to such monitoring results.

Jan 1, 2015

By J. W. Bawden, J. Nantel

"The mine operator has two prime objectives when he operates a mine: (l) the mine must be safe, and (2) the mine must operate with the lowest possible costs. The operator constantly faces a dilemma; if he is over cautious with regard to safety, his costs may be very high, and if he is over-zealous in trying to reduce costs, the safety of his operation may be jeopardized.Modern bulk mining methods rely heavily on high productivity non-entry stoping techniques (e.g. open stoping, VCR, etc.). Such techniques have the advantage of removing the operator from the active and sometimes dangerous mining face and ofminimizing costly development. On the other hand, this generally results in a certain loss of flexibility in following irregular ore-waste contacts. If stopes are opened too large and/or are inadequately supported, severe dilution with resulting escalating costs usually results. If initial access drift support is inadequate for latter mine induced stresses high rehabilitation costs may also be incurred.Optimization of stope dimensions should logically occur as part of a general mine rock engineering program, within the over-all mine planning context. The same program should help highlight those areas where drift rehabilitation may be a problem.Whenever successful mining is performed, rock engineering is being applied, either by design or by chance. The cost implications of planned practical rock engineering as an integral part of mine planning and design can be very significant to the ultimate mining ""bottom line"". At Noranda Minerals Inc. allowable stope dimensions are derived using a combination of numerical stress analysis and empirical design techniques. This paper discusses the use of the above techniques and their limitations as tools for rock mechanics based stope dimension optimization. The potential cost implications of such design efforts within the general mine planning context are also addressed."

Jan 1, 1989

By A. E. Gran

"QIT -Fer et Titane Inc. currently produces and markets four main products: a titania slag named SORELSLAG for the white pigment production, a high purity pig iron known as SOREL-METAL mainly used in the ductile iron casting industry, an ilmenite ore for blast furnace applications called SORELFLUX and high quality steel billets SORELSTEEL employed in the wire rod fabrication. Moreover , QIT also manufactures high quality iron and steel powders labeled ATOMET for the powder metallurgy industry through its wholly owned affiliate. Quebec Metal Powders Limited. The company operates. rock ilmenite mine near Havre St. Pierre and produces its slag and ferrous products from its metallurgical installations located in the Sorel/Tracy region. QIT. born in 1948 from a joint-venture between Kennecott Copper Corporation and New Jersey Zinc Company, was acquired from BP Minerals by RTZ Corporation PLC in 1989 and remains its wholly owned subsidiary ever since.lImenite is a mineral rich in both titanium and iron oxides. QIT's proprietary mineral enrichment and electric smelting processes permit the concentration of the ilmenite ore and the separation of its main constituents to produce a 80% TiO2, slag and a high purity molten iron which is further transformed into iron ingots (pigs), steel billets, iron and steel powders.QIT's ilmenite deposit is located in the Lake TIo-A1Iard area, 43 km inIand from Havre St. Pierre, a community on the north shore of the St. Lawrence River some 960 km from Montreal. The orebody, covering some 542 000 m2, consists primarily of coarse-grained ilmenite (FeO.TiO2) with disseminated fine lenses of hematite (Fe2O3). The worthless mineral (gangue) associated with ilmenite is mainly anorthosite, a complex silicate. QITs mining operations are carried out using conventional open pit methods in a 500 m by 600 m horse-shoe shaped mine with nine benches developed. Primary blasting is performed on a weekly basis during the mining season. Blasted ore is trucked to the crushing station to be broken down to 15 cm and 7.5 cm sizes, respectively, by means of a primary jaw crusher and a secondary cone crusher. Minus 7.S cm ilmenite is then loaded into hopper cars for the 43 km trip to the Havre St. Pierre terminal where it is stockpiled and reclaimed by under-ground conveyor chutes to a ship loading tower at the dock. The crushed ore is shipped to QIT's smelter located in Sorel in 40 000 tonne carriers from April to December."

Jan 1, 1995

By W. H. Gross

To pollute means to make impure or unclean. We tend to forget that man defecates, urinates, sweats, expectorates and exhales and in himself is a beastly little pollutor-but then so is Mother Nature! The object of this paper is to try to put what man and nature do into perspective. The facts indicate that although man may sweat a little, Ms. Nature is by for the greatest pollutor of all.

Jan 1, 1979

By Arthur. H. Winckers, Stephan L. Chryssoulis

"The deportment of gold in residue samples of cyanide leach tests of David Bell ore from level 6A block 13 was established using a comprehensive quantitative mineralogical approach. In every test the feed was first pre-aerated for 4 hours, followed by 48h cyanidation. Test no. 2 was done without lead nitrate and yielded a residue assaying 3.03g Au/t. In test nos. 4 and 9 lead nitrate was added before pre-aeration at 0.03kg/t and 0.3kg/t respectively yielding residues of 1.04 and 0.81 g Au/t.The mineralogical approach employed to establish the deportment of gold involved superpanning, to preconcentrate the free gold and assaying of the tailing fraction to determine the gold associated with quartz. It was thus determined that without lead nitrate added 47.2% of the lost gold is in the form of residual free gold particles less than 20 µm in size. It is this form of gold which is under represented in the residues of leach tests with lead nitrate added.Having eliminated coarseness of gold particles as a factor for lower recovery, it was determined that the residual gold particles have extensively contaminated surfaces. Amongst the deleterious surface contaminants identified: S, As, Ag, Sb and Hg, the two most harmful are S and Hg because of their concentration on the surface and rate of accumulation.Mercury and Ag are minor constituents of native gold at David Bell (average composition Au: 78.9 wt%, Hg: 18.5 wt% and Ag: 2.6 wt%) and they become enriched on the surface of residual gold particles because of their slower rate of dissolution in cyanide. The other elements absorb onto the gold particles from solution.The beneficial effect of lead nitrate was documented by comparative surface analysis of gold from residue samples of 48 hour leach testing with and without lead nitrate added and from time dependent (0-2 hour) leach tests in the presence and absence of lead nitrate. Lead nitrate accelerates the dissolution of gold by performing the following functions: (i) catalytic effect on the cyanidation of gold by accepting electrons; (ii) reaction with surface sulphur to form PbS which is then removed by oxidation; (iii) catalytic reaction on amalgam and Ag facilitating the cyanidation of Hg and Ag thus slowing down their build up onto the dissolving gold particles and (iv) the precipitation of sulphide sulphur from solution thus minimizing its build up on the surface of dissolving gold particles which is believed to facilitate the access of cyanide ions."

Jan 1, 1996

By Ramsey Hart

MiningWatch Canada is the only national independent civil society organization with an exclusive focus on mining in Canada and Canadian mining companies operations internationally. In 2005, MiningWatch Canada collaborated with other NGOs to develop the Framework for Responsible Mining: A Guide to Evolving Standards. The project was the result of a perceived need by NGOs and retailers, particularly from the jewellery sector, for a framework that would set out environmental, social, and governance standards for the minerals sector ?providing recommendations for retailers and others seeking to source or invest responsibly, as well as regulate and encourage responsible mining practices?. This paper is a reflection on the Framework that examines key areas of concern and notes where the industry norms and expectations of civil society have evolved. The paper focuses on developments in social issues related to the UN Guiding Principles on Business and Human Rights, new initiatives associated with financial transparency, the UN Declaration on the Rights of Indigenous Peoples. The environmental components of the Framework that are revisited are waste management, biodiversity, energy and climate change, environmental assessment, mine closure, mercury and seabed mining.

Aug 1, 2013

By Wang Wenqian, George W. Poling

"Devices and flowsheets for recovering fine placer gold are reviewed. Inefficiencies of gravity processing techniques are documented and discussed. Prospects of combining gravity and froth flotation techniques are presented. Possibilities of using other separation techniques, such as magnetic and electrostatic devices are also discussed.IntroductionSeveral new methods for beneficiating different types of placer ores have been developed in the last two decades. Improved efficiencies in the recovery of fine particles have been achieved by improving gravity flowsheets and machines as well as by developing multiple treatment techniques involving flotation, magnetic and electrostatic separations. Placer gold processing, however, has been an exception to some extent. Gravity concentration using riffled sluices accompanied by mercury amalgamation is still the main method in use today. Because of this, the recoveries of fine gold and the other associated values are often similar to those achieved several decades ago. For example, very few sluice systems recover significant placer gold finer than 100µm in size.Only a few proposals for using alternatives to simple gravity methods for recovering fine placer gold can be found in the published literature. The fixed, low gold price discouraged research in this field for many years. Development of more efficient processes has not kept pace with the recent rapid escalation in the price of gold. Froth flotation for saving fine placer gold might now prove economic, for example. This paper reviews literature published on the recovery of fine placer gold over the period 1907 to 1980. Suggestions for improving the performance in this field, based on the authors' current testwork, are also presented."

Jan 1, 1983

By Fathi Habashi, Michel Pagé, Farouk T. Awadalla

"Chrysotile asbestos can be dyed with certain dyestuffs to form stable coloured products whose hemolytic and cytotoxicity are greatly reduced. Examples of these dyes are Thiazol Yellow G (a monazo dye) and Trypan Blue (a diazo dye). Other dye stuffs, for example, basic dyes with triphenyl methane structure, Brilliant Yellow (a diazo dye), and Methylene Blue (a thiazine dye) colour asbestos but do not reduce its toxicity. Similarly alizarin, 8-hydroxyquinoline, and representative members of the phthalein group Bromocresol Purple and Phenolphthalein.IntroductionThere is, at present, a controversy regarding the dangers of asbestos fibres, and attempts are being made to render it less toxic. One of these attempts consisted of treating chrysotile asbestos with gaseous phosphorus oxychloride, POCI], at ambient temperature and in absence of moisture. The product had to be heated at 300°C to 500°C to expel exess entrained reagent to get a material containing 0.5070 to 5% phosphate groups and known as Chrysophosphate (Lalancette and Dunnigan, 1982). This product showed decreased toxicity as measured by its hemolytic effect on red blood cells (fable 1). In another approach, Flowers (1983) showed that when chrysotile asbestos was thoroughly mixed with a solution of ferric ammonium sulphate and the slurry was then filtered and dried, the product showed a marked decrease in cytotoxicity.In the present investigation the problem of toxicity was considered from a different point-of-view. Chrysotile asbestos is a hydrated magnesium silicate that can be represented by the structural model shown in Figure 1 from which it can be seen that magnesium hydroxide groups, Mg(OH)2, form a part of the silicate structure. Certain organic reagents that are known to react with magnesium ion in solution to form chelates were reacted with asbestos to find out whether a chelate was also formed on the fibres, and if so , what will be the hemolytic action and cytotoxicity of the product."

Jan 1, 1991

By O. A. Carson

Introduction Although the equilibrium conditions of the copper-tin alloys have been the subject of a ?great amount of research, the equilibrium diagram is still in doubt. The first systematic investigation of the series was made in 1894 by Le Chatelier, who published a freezing-point curve. In 1895, Roberts-Austen and Stansfield published the complete liquidus and partial solidus curves, which they modified somewhat in 1897. Their liquidus as given in 1897 is essentially that accepted today (Figure 3). Haycock and Neville also published a liquid us curve in 1897. In 1898, William Campbell published a series of micrographs showing the changes in microstructure which accompanied the thermal changes of Stansfield? s diagram. The classic work on the bronze series was published by Heycock and Neville in 1903. Their diagram was based on both thermal and microscopic evidence, and is the first for this series of alloys which can be considered nearly complete. Further, it was the first bronze diagram in which any attempt was made to apply the phase rule in the interpretation of the thermal and microscopic results. That portion of Heycock and Neville's diagram covered by the present work is reproduced in Figure 7.

Jan 1, 1929

By Cale J. Dubois

At Cameco Corporations' Cigar Lake Project, large excavations are developed on the 480 Level and 500 Level must remain stable for at least 15 years to host underground processing infrastructure. Following the successful dewatering of the mine in October 2009, subsequent internal rockmechanics investigations augmented by third party technical investigations; determined that to keep the back of the Water Flush Crusher/Run-of-Mine (WFC/ROMs) excavation stable; required a rehabilitation strategy to mitigate deterioration/deformation of the WFC walls and intersection pillars. The mechanism of failure propagating the movement of the excavation walls is understood to be controlled by the presence of a dominant E-W striking and steeply dipping foliation within a relatively weak and mildly altered rockmass sub-parallel in strike with 14 meters high walls and an intersection span approaching 15 meters. The application of open and resourceful communications between site mining engineers, geologists, contract mining staff, construction management experts, corporate mining and civil engineers, and third party technical experts resulted in a multi-faceted short-term ground support strategy consisting of standard bolting and screening, deep-seated modified-strand cable bolts coupled with heavy gauge mesh straps, rockmass reconditioning using low-pressure grout injection, and horizontal cable-lacing for the intersection pillars applied in lifts using a top-down methodology. The intention of the short-term strategy was to stabilize the excavation so that a long-term structural steel support installation - consisting of composite concrete walls, and arch support applied to the side walls and crown of the back - could be constructed safely. This paper summarizes the evolution of the short and long-term ground support strategy and criteria for the WFC/ROMs excavation developed using elements of civil, mining and hydrogeologic design.

Nov 1, 2011

By D. C. Carter

"The Nova Scotia Department of Mines and Energy located a drillhole at Riverside Corner, Hants County, Nova Scotia, to examine the stratigraphy, structure and potash potential of the Kennetcook River gravity low. This evaporite-related gravity anomaly is one of the largest virtually unexplored gravity anomalies in Nova Scotia. The drillhole intersected a structurally complex sequence o flower Windsor Group ('B' Subzone) evaporites. Downhole geophysical wireline logs were used, in conjunction with detailed lithological descriptions, to interpret the structure and stratigraphy of the sequence. Similar application of total gamma ray, density, caliper and neutron-neutron log responses allows stratigraphic correlation of Windsor Group carbonate marker units separated by up to 35 km in Cape Breton. This work confirms the value of downhole geophysical logs as a tool in the exploration of evaporite deposits regardless of the presence or absence of high quality core. INTRODUCTIONThe exploration methodology for evaporite (specifically salt/potash) deposits in eastern Canada (and worldwide) is relatively simple: identify a negative gravity anomaly within a favourable geological setting, Windsor/Cordroy Group sediments in eastern Canada, and drill it (Anderle, 1980). Although this is an obvious oversimplification of the necessary expertise in the planning and complet ion of an exploration program, those familiar with potash exploration drilling can attest to the risks and expense, in terms of time and problems , associated with the location and drilling of diamond-drill wildcat holes. Potash exploration programs in eastern Canada, their results and inherent difficulties, have been documented by Anderle et al. (1979), Cooper (1981), Dekker (1982), Carter and Boehner (1986), Carter (1988) and Carter and Anderle (in prep .).Downhole geophysical wireline logs have become an important tool in the stratigraphic and structural interpretation of evaporite sequences in eastern Canada and, in many cases, represent the only information recovered or the only information available due to the drilling method (rotary) and/or the long term instability of evaporite cores. This paper documents examples of downhole geophysical log responses which, combined with detailed lithological examination of drill core, or in the absence of core, are used in the interpretation of the complex lithology and structure of a deformed evaporite deposit. Geological and geophysical data from the Nova Scotia Department of Mines and Energy (NSDME) Riverside Corner 85-1 drillhole are presented here as a partial case history and prime example of the use of this method to interpret the complex structure of an evaporite deposit. Drilling of NSDME Riverside Comer 85-1 was conducted in late 1985and early 1986by the Department (Carter and Boehner, 1986) under a program to assess the potash potential of selected areas of the province as part of the Canada-Nova Scotia Mineral Development Agreement 1985-89. A reinterpretation of a portion of the available data from two exploration drilling projects on Cape Breton Island in the Canso-Bras d'Or area is also presented (see inset, Fig. I). Several drillholes have intersected the Windsor Group evaporite sequence in these areas and the available geophysical logs are a valuable tool in the interpretation of the structure of the deposits. However, no attempt has been made to present or discuss the detailed geological investigation and comparison of these two deposits. They are presented here as an example of the reinterpretation of existing data and their application to stratigraphic correlation and structural interpretation of complex evaporite deposits. Further work is necessary to document the stratigraphic and structural correlation of these two areas."

Jan 1, 1989

By J. R. Emery, D. F. Coates

"FOUR PAPERS ON CEMENTED BACKFILL were given at the Annual General Meeting of The Canadian Institute of Mining and Metallurgy in 1970:Weaver, W. S., and Luka, R., ""Laboratory Studies of Cement-Stabilized Mine Tailings"".Pasieka, A. R., Beattie, H. F., and Espley, G. H., ""Cemented Hydraulic Backill within the Falconbridge Group of Companies"".McLeod, P. C., and Schwartz, A., ""Consolidated Fill at Noranda Mines Limited (Geco Division)"".Clement, W. P., and Sokoloski, R., ""Pumping Cemented Backfill"".These four papers give the impression of a development in mining technology that has been substantially completed. Somewhat over ten years ago, The Inter-national Nickel Company of Canada, Limited and Falconbridge Nickel Mines Limited started experimenting with the addition of Portland cement to mill tailings to produce improved backfill and cheaper floors for scraping. Shortly after, the Canada Cement Company Limited (now Canada Cement Lafarge Ltd.), with full support of the two mining companies, started an extensive research program to provide the technologic-al data necessary to exploit what was obviously going to be a significant development in mining technology."

Jan 1, 1970

Since 2008 rapid advances have been made in technologies for the sensing and sorting of ores, particularly copper, and copper-related ores. Advances include significant increases in the sensitivity and throughput, specifically in the area of bulk sorting. Such advances were not possible without contemporaneous advances in the understanding of copper orebodies, in particular the understanding and quantification of the heterogeneity required within an orebody to support an effective sort, regardless of the technology deployed to do this. This paper covers fundamental knowledge in the characterization of orebodies and their ores for sorting; relationships between measures of heterogeneity and sorting response; the design of bulk sorting systems that can exploit this heterogeneity to add value to copper operations; and, a quantification of the value that can be generated from bulk sorting at a case study mine. INTRODUCTION Society currently puts increasing pressure on industries to move towards cleaner and more efficient means of production, and the mining industry is no exception. Mining additionally faces other factors increasing the pressure to be more efficient: high-grade and easily accessible reserves have become largely depleted, therefore the mined grade at operations across most commodities, including and in particular copper, is decreasing. Additionally, the grade of new discoveries in the sector continues to decrease (Schodde, 2011). Factor in the high capital cost of processing facilities and the low levels of efficiency of current grinding circuits, and the situation for such mines becomes dire. Sorting, by maximizing the amount of ore extracted while simultaneously reducing the waste content in ore delivered to downstream processes (whether simply transport and crushing, or more sophisticated circuits such as grinding and flotation or leaching) has long been of interest to mining operations and projects struggling with low margins (Bamber, 2012). However, until recently sorting technologies that are both cost effective and effective at such high throughputs have not been commercially available.

Jan 1, 2019

By Barry James

Energy, like labour and materials, is one of the basic production inputs in the industrial minerals industry. This paper discusses the significance of the changing energy situation in Canada as it affects the industry. It is apparent that the importance of energy as a management concern has increased considerably since 1973. The importance placed on energy management today will undoubtedly be an important factor in determining company and industry sector strength and profitability tomorrow.

Jan 1, 1978

By Pierre Pelletier, Christian Pichetie, Dany Pelletier

"IntroductionDuring 1994, Barrick Gold Corporation, or American Barrick at that period, acquired Lac Minerals Ltd. properties. One of them was the Bousquet Complex. The Bousquet Complex is divided into three distinct sites: one mine (Bousquet 2), one mill (Est-Malartic Division) and one analytical chemistry laboratory (Les Terrains auriferes).The Bousquet 2 orebody was discovered in 1986. An extensive drilling program was initiated during 1987. Its purpose was to define the orebody extent. At the end of 1997, gold production from Bousquet 2 mine reached 1 290 000 oz of gold from a cumulative tonnage processed of 4 175 000 M t.From 1980 to 1990, the Est-Malartic mill was used for the treatment of ore from the following mines: Bousquet 1, Doyon, Francoeur (Richmont mines), Buckshot and 1-20 stope. At present, the mill receives ore from the Bousquet 2 mine.HistoryThe Est-Malartic mill is located close to the town of Malartic in northwestern Quebec. The mill has been in production since the mid-1930s processing mainly clean, free mill gold ore. Active mining from the Est-Malartic mine ceased in 1979 and the mill was switched to custom processing of ore from La Mine Doyon located some 45 km to the west. This custom processing arrangement continued until 1987 when the expanded mill at Doyon became available to process all of the Doyon production. In 1987, Lac Minerals commenced development of a second mine at the Bousquet site located 40 km west of Malartic. This mine, Bousquet 2, is the down dip extension of the La Ronde mine developed by Agnico Eagle. During pre-feasibility evaluations, it was determined that it would be economically more attractive to modify the existing Est-Malartic mill than building a new facility on site. The Est-Malartic mill modifications for processing the high-copper/gold ore from the Bousquet 2 mine began in late 1989 and new circuits were commissioned in mid-1990. Modifications included the addition of both gravity and flotation concentration circuits to recover coarse, free gold and the copper. The existing leaching circuit continued to operate on the copper flotation tailings with some minor modifications to the solution handling systems. A S02/Air cyanide destruction circuit was also added at that time."

Jan 1, 2000

"8.1. IntroductionThe stoichiometry of most named platinum-group minerals (POM) is known (cf. Cabri, 1981b, in Chapter 7), but, because these minerals are subject to a wide range of element substitutions, representative analyses require treatment in a separate chapter (section 8.2). The analyses, in all cases done by electron microprobe, are grouped in sections according to the principal platinum-group element (POE) for each POM, and then follow sequentially with increasing amounts of the principal POE starting with the ideal composition, when known. In order to facilitate reference to specific POM by name, an alphabetical listing is also given (Table 8.1). A range of compositions, in addition to one or several ""representative"" analyses, is given for some POM when more than one analysis has been reported for a particular locality. The tables of POM analyses (Tables 8.2 to 8. 76) include at least one analysis for every locality for which data have been published, to the best of the authors' knowledge. All analyses are referenced for locality and publication source, and include several unpublished analyses (all but one done at CANMET). Most analyses have been rounded off to one decimal place for amounts more than one per cent and their formulae calculated on the basis of an even number of total atoms. In all tables, ''n.d.'' stands for elements sought for but not detected and a dash signifies elements not sought, or when these haven't been specificed in the publication source.Section 8.3 contains tabulated analyses and, in some cases, also includes a critical assessment of POE-bearing minerals in which the POE occur in trace or minor quantities. The organization of the data in this section is by mineral groups; e.g., sulphides, sulpharsenides, silicates, etc. Some of these data are also discussed in Chapter 4 by Crocket (1981) and are discussed briefly in Chapter 6 by Crocket and Cabri (1981)."

Jan 1, 1979

By Dave Thomas

?Uranium is a common trace metal at the earth?s surface, but these are amazing super-high grade (up to 25%) pods, veins and disseminated uraninite (UO2) near unconformities between Proterozoic siliciclastic red beds and metamorphic basement with graphitic metapelite and radiogenic granite. ?Pitchblende fills extensional features in reactivated fault zones and replaces matrix in sandstone ?One mining district in Canada ?the Athabasca Basin ->30 deposits /prospects -most in eastern ¼of basin -produces 1/3 of world?s U -employs northerners -VERY high tech -VERY high safety standards Unconformity-associated uranium depositsUnconformity-deposits

May 1, 2006

By Leslie B. English

"HistoricalWHILE DIGGING caves and underground passages for living quarters, primitive man must have had some means of illumination. Most likely he used pieces of wood or slim bundles of reeds or grasses as torches, perhaps steeped in animal fats to give more light. If this is so, we may accept these as the first means of underground illumination. Very little was clone to improve lighting devices for many generations, but slowly there was developed a fount holding fatty oils, with a spout in which was inserted a form of wick.Actual mining. for metals first of all, was started about 3,000 B.C. Some of the old Greek and Roman records refer to the use of torches underground, and some evidence of clay lamps has been found. Candies came into use some time during the first century A.D. When coal mining began about the 14th Century in England, candles were used for illumination because of the ease of manufacturing and handling them. Open oil-lamps came into use early in the 16th century -Agricola, in his De Re .Metallica, written about 1540. pictures a miner with such a lamp. However, the expense of these was so great that candies still continued as the general means of underground lighting.Unfortunately, as miners went deeper underground, they encountered a mysterious gas which. upon coming in contact with open lights, flamed violently, resulting in explosions and accompanying loss of life. The first reference to the results of these gas explosions appeared in 1621. No help seemed to be available. The gas was given off when the coal was mined and the miners could not see without lamps. Attempts were made to use the phosphorescent glow from partly decayed fish, fish skins, and fungus, also to bring daylight clown into the workings by means of a series of • mirrors; •but these means of illumination proved to be impracticable."

Jan 1, 1955