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By C. E. Smith, R. J. Inglis, M. I. Brittan, J. H. Schoeman

"AbstractA number of plant-scale cyanidation tests were carried out in an attempt to uncover the causes of fluctuations in gold recovery efficiency. Computer analysis of the results verified that the treatment of reclaimed waste rock material along with normal run-of-mine ore was having an adverse effect on metallurgical efficiency. Mineralogical examinations showed that the free gold particles in the dump material were heavily tarnished or coated (predominantly by hydrated iron oxide), accounting for the lower recoveries. The indications were that the effect could be counteracted somewhat by using higher than normal cyanide and lime reagent concentrations and adequate leaching times. Analysis of the results showed further that leach pulp density was an important operating parameter affecting extraction efficiency. A variable activation energy leaching model provided an extremely good characterization of individual batch leach runs.IntroductionFLUCTUATING METALLURGICAL EFFICIENCY at the gold concentrator of the S.A. Land and Exploration Company Limited (""Sallies"") prompted some plant-scale cyanide leach studies in an endeavour to uncover the causes of the variations in gold recovery."

Jan 1, 1977

By S. W. Marcuson, P. J. Mackey

The Canadian non-ferrous mining and metallurgical industry has made great strides in environmental protection during the past half century. The path taken by the copper-nickel smelting industry in reaching today’s level is traced in this paper. Following the practice at early copper smelters in Wales and in the US, Canadian smelters originally used tall stacks to disperse furnace of-gases. This was the normal mode of operation and was accepted by society and by Government. Gradually, Government regulations required fixation of sulphur dioxide emissions and Canadian companies responded with significant technical developments to achieve this result. The initial development in Canada of the first new technologies such as the Cominco Flash Suspension Roaster and the Freeman Flash Smelting Process - both representing early versions of the modern established flash smelting technologies - and then later technologies such as the Inco Flash Smelting Process and the Noranda Process, both of which continue to this day, are discussed in this paper in terms of their contributions to the development of environmentally friendly plants. The evolution of these and other technologies is also discussed. Some comments regarding how the industry will face the future are also included.

Jan 1, 2015

By John F. Gartner

"New terrain maps provide information on the ground conditions in northern Ontario. This information has a relevance to mineral exploration because it assists the user in determining ground conditions prior to entering the area. The prospector, geologist, geophysicist and geochemist can then plan for the optimum use of exploration techniques best suited for theseground conditions.These terrain maps are the result of the Northern Ontario Engineering Geology Terrain Study-a program carried out by five consultants under contract to the Ontario Geological Survey of the Ministry of Natural Resources. The area mapped is 370,000 km2 and more than 100 basic data maps at a1:100,000 scale will be published.An unique terrain legend was derived to facilitate the mapping and it allows the derivation of specific user information. Examples of some of these uses are described. Introduction""Where did all the boulders come from Charlie?"", asked the student, as the prospector and his young assistant clambered through the bush. "" Why son, they were brought down here by the glacier"", the prospector replied. ""But where is the glacier now Charlie? "", persisted the young man. ""Gone back up north for more boulders son!""An old story, but one that illustrates the importance of overburden to the prospector. The use of overburden as a prospecting technique is not new. In fact, the principles have been known in the western world for at least 235 years (Shilts 1976). More recently, Dreimanis's classic work on boulder tracing (1957) and Lee's work (1971) emphasize the role of glacial geology in prospecting. In addition, papers by Smee and Sinha (1979), Averill (1978), Bereton (1978), and Gleeson and Hornbrook (1974) all describe the importance of drift in mineral exploration programs. The discovery of the copper deposit in the northern Ontario township of Currie (Thompson, 1979) is attributed in part to till prospecting methods. So the significance of the overburden is firmly established, both in the literature and in the minds of today's prospectors, geologists, geophysicists and geochemists."

Jan 1, 1981

By D. J. McLaren

"Arctic Canada is one of the largest undeveloped terrains remaining in the world, and is in many ways unique. The ecological balance of the region is more delicate than tropical or temperate regions of similar size. This region is likely to be developed by research for and production of resources, primarily petroleum, in the immediate future. As well as sensitive terrain surface caused by permafrost in some areas, many large and small mammals and birds are also in a delicate balance with the environment. Small changes in this balance can have large effects.The probability of finding petroleum in different regions varies widely, but already there are good indications on the mainland and in the Islands that both oil and gas are present. Geophysical work in the offshore, particularly the Beaufort Sea, suggests further promising potential. Possible reserves in the Islands and mainland Arctic may amount to 50 or more billion barrels.A responsible approach to problems facing exploitation in an Arctic environment includes the careful monitoring by industry of likely effects of their activities. The Mackenzie Valley Pipeline Research Association test loop at Inuvik provides an example of such monitoring. Outside Canada, the operations at Prudhoe Bay on the north coast of Alaska show how major companies may operate responsibly and reduce environmental interference to a minim'.::at. Nevertheless, four variables must affect any decisions to be made concerning energy resource exploitation in the Arctic. These are man's need for energy, economic and industrial pressures to develop energy sources, the desire to preserve a deteriorating environment, and the role of government as representing all individuals in the country and their several points of view. Factors that must be taken into account in making any decisions include the importance of Canadian oil in a world picture, the need for alternative sources of energy in the near future, the depletion of nonrenewable resources at an accelerating rate and the increasing awareness that the major problems facing man have no direct technical solution and that social or political decisions must precede further techno-logical development."

Jan 1, 1971

By I. C. Christopher

Introduction The geology of the Cochen-our Willans gold mine has been described in reports by the late Dr. H. C. Horwood (1) in 1940 and by Dr. J. P. Nowlan (2) in 1947. Information from these and other (unpublished) reports has been incorporated in the present paper, together with some recent ideas regarding structural features which are at present being used to locate ore shoots. Location and History The mining claims of Cochenour Willans Gold Mines, Limited, occupy 705 acres in Dome township, on the east shore of Red lake opposite McKenzie island. Adjoining properties are those of McKenzie Red Lake Gold Mines on the west, Boymar Gold Mines on the north, Marcus Gold Mines on the east, and Martin-McNeely Gold Mines on the south. The claims of the original group were staked by W. M. Cochenour, Dan Willans, and H. G. Young, and the Cochenour Willans Syndicate was formed in 1928. Work was carried out by the Syndicate and several other companies during the next eight years with inconclusive results, due to the irregular occurrence of the ore. In 1936, Cochenour Willans Gold Mines, Limited, was incorporated and production was finally started late in 1939.

Jan 1, 1951

By Marsh A. Cooper

THE THEME of my remarks provides a great deal of latitude. I shall therefore take advantage of the scope it offers to look at our industry across a broad spectrum. My observations reflect a Canadian mining man's varied career as a geologist, mine operator, geological consult ant and company executive in Canada and overseas ... under differing cultures, business environments and political jurisdictions. I was fortunate to come into this industry in the mid-1930's when it was characterized by great enthusiasm, drive and resourcefulness. It was the beginning of a burgeoning era of some 30 years' duration in which the individualist, the entrepreneur and the builder found ample room for expression. As I contemplate the environment in which we now have to operate and try to perceive what lies ahead, I find myself deeply disturbed. Something serious has happened to this industry along the way. It appears that our very success has been the source of our undoing. I believe it is useful to summarize our industry's basic strength at home as a take-off point f or assessing its position in world terms. I hope that I can focus on some of the things that, in my view, must be done for this industry and by this industry to restore Canada's historic role in the world mining community. The Canadian mineral industry provides 140,000 jobs. It pays the second -highest average weekly wages and salaries among the country's major industries. The output per employee in the mining industry is estimated at about three times that for the economy as a whole.

Jan 1, 1977

By Mafalda Arias

Most mining and mineral exploration companies? operate in remote locations, in Canada or internationally. Not knowing the cultural imprint of your team and the places where your company is active, may lead to problems. To set the foundation for a better world, it?s important to built trust and relationships inside your global team, within communities and together with stakeholders. Building the ?invisible asset? and developing intercultural awareness is an important part of leadership programs for geologists and engineers on your team, and should be a key component of your Corporate Social Responsibility initiatives. Why is culture important for mining and mineral corporations in their CSR initiatives? Because culture is the foundation of your organizational identity. Understanding the impact of identity, for an organization and for each individual, will provide a description of the experiences and values that affect every work placed interaction, with your clients, with colleagues, with suppliers, with the community of the host country. Each one of us sees and evaluates the world through our perceptions. Through these perceptions we give meaning; how we view and understand our reality which sets the tone for how relationships are built. This is what I call building the ?invisible asset?. Identity, experiences, values and beliefs are invisible commodities, locating them can be as difficult as finding a mine. But if they are not located, the commodity does not have value. Just like in the work we do in our industry. For example when you are working in an underground gold mine and the vein is lost, you keep on working and trying to find the vein; time passes, money is being used and no results. You decide to bring an expert on this type of deposits who gave you directions that allowed you to find the vein. To be a responsible citizen of the world and to set the foundation for a better world, it is imperative to go deep, as deep as your next drilling program, because only there and then, can you develop the cultural sensitivity and the ability to become an agent of change for responsible, sustainable and profitable businesses.

Oct 1, 2010

By L. M. Dwarkin, D. F. Coates

Crows Nest Industries Limited adopted roof bolting in 1963 to improve roof control and to extend continuous miner utilization in one mine. Bolting was held back because anchorage tests gave inconsistent results. The time lapse between mining and bolting was suspected as a cause, and so a test entry was driven and sections of it were bolted as part of the work cycle in addition to the normal timbering. This paper presents the results of the instrumentation of test entries and discusses the utilization of the data to improve mining procedure.

Jan 1, 1967

By M. L. Haider

Introduction I Appreciate very much the opportunity of discussing with you tonight oil developments in western Canada. These developments are of importance to all of us, first because of their great economic significance to all of Canada, and second because of the location of the new oilfields. Situated as they are in the west and northwest, they are of considerable strategic value from the standpoint of continental defence. The story of oil development in Canada covers a span of almost a century, during which time success in finding reserves of petroleum was barely sufficient to maintain interest in continuing the search. Finally, in 1947, a well of the first importance was completed in Alberta and, judging by discoveries made since then, it appears that Canada, at long last, is to become an important producer of petroleum.

Jan 1, 1950

By B. Yu, S. Kelebek, C. Gibson, M. Aghamirian

There are a number of high grade niobium deposits worldwide which have been deemed untreatable by flotation due to the very fine grained nature of the in situ pyrochlore, the primary niobium bearing mineral. A known method of recovering extremely fine particles is through the use of chelating reagents such as hydroxamic acids which have a strong affinity for transition metals. However, one of the major issues in the flotation of niobium bearing minerals using hydroxamic acids is the corresponding recovery of other transition metal gangue minerals including magnetite, hematite, and pyrite. In order to better understand the differences in behavior of niobium and iron bearing minerals in flotation with benzohydroxamic acid (BHA) and sodium hexametaphosphate (SHMP) at a range of pulp temperatures, a Box-Behnken experimental design was employed. Regression models for the global recovery of iron indicated that iron mineral recovery was significantly influenced by both BHA and SHMP dosage. Upon examinination of flotation products by semi-quantitative XRD, it was observed that recovery of iron oxide and sulphide minerals (hematite, magnetite, goethite, and pyrite) was problematic at high benzohydroxamic acid dosage, while sodium hexametaphosphate was mainly helpful for carbonate mineral depression. Iron rich carbonates (likely an iron rich dolomite) largely reported to the tails with increased SHMP dosage.

Jan 1, 2015

By Guoqiang Lan, Jun Song, Bin Ouyang

Rare-earth pyrochlores, commonly exhibiting anomalously low lattice thermal conductivities, are considered as promising topcoat materials for thermal barrier coatings. However the structural origin underlying their low thermal conductivities remain unclear. In the present study, we investigated the phonon properties of a group of RE pyrochlores, Ln2Zr2O7 (Ln = La, Nd, Sm, Gd) employing density functional theory and quasi harmonic approximation. Through the relaxation time approximation (RTA) with Debye model, the thermal conductivities of those RE pyrochlores were predicted, showing good agreement with experimental measurements. The low thermal conductivities of RE pyrochlores were shown to largely come from the interference between the low-lying optical branches and acoustic branches. The structural origin underlying the low-lying optical branches was then clarified.

Jan 1, 2015

By Loris S. Russell

THE plains of southern Alberta constitute one of the classic areas of geological investigation in Canada, for it was here in 1874, and in 1881 to 1883, that George Mercer Dawson (1, 2, 3) made the pioneer observations that are basic to all subsequent work on the interior plains of Canada. Dawson's work was extended eastward by R. G. McConnell ( 4) and northward by J. B. Tyrrell( 5) , but it remained. for D. B. Dowling to re-examine Dawson's Bow and Belly River Area and to make certain necessary revisions in the stratigraphical system of his predecessor. In 1917, Dowling published his memoir, The Southern Plains of Alberta( 6) , which remained for over ten years the last word on the stratigraphy and structure of the area described. It is generally conceded that Dowling's work made known the existence of a great artesian basin beneath the semi-arid plains of southeastern Alberta. In addition, his structural studies greatly stimulated the search for natural gas and petroleum. The most recent general publications on this area by the Geological Survey are based on the field work of M. Y. Williams, E. J. Whittaker, W. S. Dyer, and P. S. Warren, between the years 1923 and 1926. Their results were embodied in the Calgary Sheet (7) and the memoir, Geology of Southern Alberta and Southwestern Saskatchewan (8). By this time, the number of geologists working in Alberta in the development of the petroleum and natural gas industries had become large, and in 1931 the Alberta Association of Petroleum Geologist~ offered the Donaldson Bogart Dowling Memorial Symposium on Stratigraphy of Southern Alberta( 9) , a most valuable series of papers descriptive both of the ,surface stratigraphy and that observed in the well records.

Jan 1, 1937

By Paul R. Terry

This paper presents a brief picture of the quality of coal produced in Eastern Canada for use in thermal generating stations. It describes, in particular, the characteristics of coals burned in six power plants -two in New Brunswick and four in Nova Scotia. Each station is dis-cussed in turn, and comments are made on the coals used therein with regards to origin and physical and chemical properties affecting station operation. A table of coal data shows, at a glance, the wide variation in the quality of coals received by these stations from producers in New Brunswick and Nova Scotia. "The promotion of improved coal quality for thermal generation can benefit our national economy." T HIS is the opening statement in a paper which was presented by Mr. D. A. Pirttinen at the Coal Division's Toronto meeting in April, 1960. In bringing the power engineer's viewpoint to the coal producers' attention, Mr. Pirttinen made a survey of utility steam plants operating in Canada, and the results of this survey formed the basis for his paper, which he titled: "Generating Station Coal Quality.

Jan 1, 1965

By R. Salimi

Tricalcium aluminate hexahydrate (TCA) is used as filter-aid for security filtration in the Bayer alumina process. TCA is typically produced on-site by mixing Bayer liquor with slaked lime. Specific properties are required from the TCA to ensure adequate filter throughput, lifetime and importantly effective reduction of solid/colloidal impurities from the solution. The effect of reaction time on morphology and particle size distribution of tricalcium aluminate was studied for a batch experiment at simulated process conditions. It was found that reaction time plays a critical role on the morphology, crystal structure (diameter and crystallinity) and particle size distribution. In the early stages of the reaction, nucleation dominates the crystallization process followed by growth dominated by agglomeration up to a mean particle size of 10 µm. The particle morphology shifted from an irregular shape to more spherical throughout the course of the reaction.

Jan 1, 2014

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 K. Adham, T. Buchholz

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

Jan 1, 2016

By O. G. Olvera

"Refractory sulfidic ores consist of materials in which gold occurs finely disseminated within metallic sulfides or forming solid solutions, with pyrite and arsenopyrite being the two sulfides most commonly associated with gold. Typical cyanide operations show poor performance and require oxidative pretreatments to increase gold recovery. Pretreatment alternatives include roasting, pre-aeration, acidic and alkaline high pressure oxidation, and bacterial oxidation. The presence of arsenic, however, introduces a serious disadvantage to the use of roasting and bacterial leaching, while high pressure oxidation involves high capital costs. This work focuses on evaluating the effect of the addition of a carbon resin as a sulfur collector on the oxidation of different arsenopyrite concentrates under atmospheric tank leaching (ATL) conditions. The addition of the resin improved the oxidation of sulfides and favored the formation of elemental sulfur over the generation of sulfate. The use of AF5 in ATL resulted in higher gold recoveries under standard cyanide carbon-in-leach and thiosulfate leaching.INTRODUCTION Refractory sulfidic ores consist of materials in which gold occurs finely disseminated within metallic sulfides or forming solid solutions, with pyrite and arsenopyrite being the two sulfides most commonly associated with gold. Gold is not readily accessible to solutions in these types of ores and typical cyanide operations show poor performance, thus making the use of oxidative pretreatments a requirement to increase gold recovery. Pretreatment alternatives include roasting, pre-aeration, acidic and alkaline high pressure oxidation, and bacterial oxidation. The presence of arsenic, however, introduces a serious disadvantage to the use of roasting and bacterial leaching, while high pressure oxidation involves high capital costs. The use of carbonaceous materials to enhance the dissolution of sulfides is not novel, and leaching additives such as coal, activated carbon and carbon powder have been considered for the improvement of bioleaching, atmospheric leaching, and pressure oxidation leaching processes. However, this type of technology has been focused mainly on the recovery of copper from copper concentrates containing chalcopyrite with less attention paid to other sulfides."

Jan 1, 2017

"The outlook for Eastern Canada is decreased coal production and for Western Canada increased production. The market for Western coal is expected to reach 40 million tons per year in metallurgical and thermal-power markets.Technical developments in Eastern Canada include successful methane drainage experiments, modifications to the shearer-loader to improve cutting rates, mechanized mining of a tail-gate stable and mechanical stowage of level brushing. In Western Canada, the most modern equipment is used in mining, beneficiating and shipping coal. Underground hydraulic experiments were started in 1969. The importance of reclamation was recognized and plans have been made to re-vegetate disturbed areas and mine dumps.The Mining Research Centre closed the field office in Nova Scotia and is preparing to open a new field office in Calgary, Alberta."

Jan 1, 1970

By X. Q. Jiang, D. L. Chen, A. Macwan

Magnesium alloy, being the lightest structural material, is a key candidate for the weight reduction of vehicles in automotive and aerospace industries; however, its poor corrosion resistance and difficulty in deformation are limiting factors. Recently, Al/Mg/Al tri-layered clad sheets have been considered as a promising alternative to improve corrosion resistance and formability of magnesium alloys. The aim of this study was to evaluate the tensile properties and deformation behavior of Al/Mg/Al tri-layer clad sheets at different temperatures and strain rates. Yield strength (YS), ultimate tensile strength (UTS), and elongation were observed to increase with increasing strain rate. With increasing temperature from -40°C to 180°C, YS and UTS decreased and ductility increased. The strain hardening exponent evaluated via three equations of Hollomon, Swift, and Afrin et al. showed a similar increase with increasing strain rate and decreasing temperature. The fractographic analysis showed partial debonding of clad interface especially at higher strain rates and lower temperatures.

Jan 1, 2015

By Real Daigneault, François Robert, J. Paul Golightly, Jean-Yves Cloutier, Jayanta Guha, Pierre Pilote

"The Casa-Berardi East, Center and West deposits, located in the Archean Abitibi, Sub province, are hosted by volcanic and sedimentary units of varying compositions, less than300 m from the Casa-Berardi fault (CBF). The CBF, a brittle structure, represents an increment in the structural evolution of a regional-scale deformation zone showing ductile-brittle behavior known as the Casa-Berardi deformation zone (CBDZ). The CBDZ is characterized by a mylonitic Sc1 foliation which is folded a.n4 deformed by a later sczfoliation in high strain zones.Four generations of quartz vein and fracture systems have been recognized within the Casa-Berardi deposits. Most economic gold mineralization, occurring in the second generation system, is found within high strain zones. This system hosts three types of mineralized structures: (1) banded quartz veins; (2) swarms of veins and mineralized host rocks; and (3) disseminated sulphides along fractures. An early carbonate hydrothermal alteration zone (pre- to syntectonic) surrounds the deposits. Alteration associated with gold mineralization is contemporaneous to late ( syn- to post-tectonic) relative to the development of progressive deformation in the CBDZ. The geological characteristics and paragenesis of the four quartz vein and fracture systems developed as an integral part of the geodynamic evolution of the Casa-Berardi deformation zone."

Jan 1, 1990