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Reaction between xanthate ions in solution and oxidized compounds present on the surface of galena to form lead xanthate is considered to be a side reaction not contributing to flotation, although accounting for some consumption of reagent. The direct reaction of lead sulphide with xanthate and oxygen to form lead xanthate is the most significant to flotation. Coadsorntion of dixanthogen is also involved. Previous work has shown lead recovery in lead rougher flotation to be a function of m [H+] where: m = concentration of xanthate in solution rHl = hydrogen ion concentration. A plausible explanation for this relationship is suggest-ed. Likewise, the experimental findings that the amount of xanthate adsorbed under certain conditions is a function of m'[H+] are explained in terms of reaction between xanthate ions and soluble basic lead salts such as PbO.PbS04? It is also shown that m[H+] should have a constant value in lead cleaners operating at a higher pH than the roughers. This conclusion is confirmed by plant data, and the value of the constant agrees well with the calculated value. The finding is useful in mill control.

Jan 1, 1965

By N. Bédard

"This paper highlights Cambior’s initial approach for recruiting and retaining its international employees, the importance of proper preparation and the support needed to ensure a competent and stable workforce.In general, most of the training and information available for human resources personnel prepares the specialist for handling various aspects of labour relations, recruitment and hiring, benefits administration, employee relocation, etc. This is usually done in a Canadian context.Only recently, has more specialized training been developed to prepare human resources practitioners for the complex issues related to expatriate employees and dealing with human resources issues in other countries"

Jan 1, 2004

By B. Meddings, O. J. I. Evans

"This paper is mainly concerned with the present and probable future role of hydrometallurgy in the production of base metals.The economic and technological bases of the hydro-metallurgical plants built and operative in the mid-fifties are compared to those in production in the mid-sixties. The trends observed are extrapolated and some estimates made concerning the probable size and type of hydrometallurgical plants which will be operative in the mid-seventies.The impact of emerging socio-economic factors such as pollution control and the market demand for specialized metal products which favour hydrometallurgical recovery processes are also discussed."

Jan 1, 1971

By Deborah McCombe

"and Bill Roscoe, Consulting Geologist and Principal with Scott Wilson Roscoe Postle AssociatesMineral property valuations are carried out for a variety of reasons, such as mergers and acquisitions, non-arm’s length transactions, initial public offerings of stocks, support of audited financial statements, fairness opinions, determination of vendor considerations, litigation, expropriation, income tax matters and insurance claims.The CIMVal Committee was formed in 1999 to review and advise on approaches to the valuation of mineral properties. CIMVal is a special committee of CIM formed on the recommendation of the Mining Standards Task Force of the Toronto Stock Exchange and the Ontario Securities Commission.After solicitation of views and consultation with various interested parties, the CIMVal Draft Standards and Guidelines for Valuation of Mineral Properties were released for comment in February 2002 and were finalized in February 2003. CIMVal’s objective was for the standards to be used by the mining industry in general and to be adopted by Canadian securities regulators and Canadian stock exchanges. To that end, the standards contain many of the definitions and concepts of National Instrument 43-101, Standards of Disclosure for Mineral Projects, which came into force in February 2001.The intent of the CIMVal Standards and Guidelines is that mineral property valuations be carried out by appropriately qualified individuals and that all relevant information be fully disclosed. It consists of two parts: standards, which are mandatory in the valuation of mineral properties, and guidelines, which elaborate on the standards and provide guidance and recommendations for the valuation process and for reporting."

Jan 1, 2003

By A. Ingelson

Conflict over mineral development and its impacts on indigenous peoples occurs in many countries around the world. Canada, Bolivia and Peru have experienced mine development for centuries in areas where indigenous communities have been and continue to be affected by the mining industry. On a global basis the mining industry continues to face the challenge of implementing meaningful consultation programs with indigenous peoples. Many governments around the world have adopted sustainable development as a policy and one important element of sustainable development is minimizing social conflict. John Moffet and Francois Bregha (Moffet & Bregha, 1996), in their analysis of the role of law reform in promoting sustainable development, noted that stakeholder participation can reduce this type of conflict. Social conflict can result in expensive litigation and costly project delays for mine developers. Meaningful consultation with indigenous peoples in areas where mine development is proposed can be a critical factor in securing a social licence to operate. A report released by the United Nations in 2005, outlined the elements of a concept called ?free, prior informed consent? (FPIC) that promotes more sustainable development. FPIC provides that mineral exploration and mining should not proceed unless the mining company has secured the consent of the relevant indigenous group(s). This paper employs a comparative approach to evaluate the extent to which three active mining nations, Canada, Bolivia and Peru, require consultation with indigenous residents and adhere to the principle of FPIC. The comparative approach assists in the identification of those consultation elements in the legal regimes of each country that can minimize social conflict in mineral exploration and mine development and therefore contribute to more sustainable development. First, we examine the legal requirements to consult with and accommodate indigenous communities in Canada, a country with a long history of mineral development over a large geographic area that has entrenched in its Constitution the protection of indigenous peoples? rights. We then turn to an analysis of Bolivia, one of the most indigenously conscious mining jurisdictions that has followed the Canadian lead in entrenching constitutional protection for indigenous peoples. Third, the approach to consultation with indigenous peoples in Peru, a nation that has not adopted the Canadian and Bolivian approaches to constitutional protection of indigenous peoples rights, is considered.

Aug 1, 2013

By Dave Shook

A Mineral Processing facility in Montreal has recently implemented a leading-edge intranet solution for monitoring the performance of plant operations, and providing condition-based maintenance. This innovative multi-faceted software implementation incorporates: web-delivered plant information systems; area-wide control loop performance assessment (using sophisticated algorithms to evaluate poorly performing controllers); and integrated alarm management functions. The system has enabled a project to improve plant operations through better process control. Maintenance technicians, engineers, supervisors and managers all can see the performance of the controllers, and the performance of the plant itself, through webdelivered graphics and reports. Information is combined from many sources, real-time, historical, relational and analytical, to provide a complete picture of plant operation. The web-based solution centralizes the administration of user access, and simplifies the deployment of several different kinds of information to many desktops. It is an extensible system that allows users to create and share their own web pages and data views. The paper will discuss the solution architecture and the improvements the I.T., operations, maintenance, and engineering groups have experienced, and overall benefits to the facility.

May 1, 2002

The negative effects of pyrite and pyrrhotite on thiosulfate gold leaching have been investigated. Possible remedies to reduce some problems are discussed. In a gold bearing pure silicate ore, 92% of gold could be extracted within 3 hours using a solution containing 0.2 mol/L ammonium thiosulfate, 0.9 mol/L ammonia, 30 - 300 ppm copper sulfate and 8.6 ppm dissolved oxygen at pH 10.26. The thiosulfate consumption was 7.1 kg/t under these conditions and could be further reduced to 3.5 kg/t by decreasing the dissolved oxygen to 0.3 ppm. Addition of 16% pyrrhotite or pyrite into the silicate slurry led to a decrease in gold extraction by 2% or 9% respectively and an increase of thiosulfate consumption by 11 kg/t or12.8 kg/t respectively in three hours. Several adjustments, such as increasing copper ion and ammonia concentration and reducing the dissolved oxygen level to 0.3 ppm resulted in increased gold extraction and lower thiosulfate consumption despite the presence of these sulfides.

Jan 1, 2005

By Côme Carbonneau

The ten -year case history of La Société Québécoise d'Exploration Minière (SOQUEM) is reviewed under the headings of the company's raison d'être, objectives, policies, structure and final goal. A brief analysis of its past operations is presented: aborted efforts, findings and developments. A projection is made of the future earnings, in terms of estimated present value, of its three main discoveries - Louvem , Niobec and Selim.

Jan 1, 1978

By Robert Hamilton

Aur Resources is Canada's leading copper mining company with producing mines and development projects in North, Central, and South America. Copper production from Louvicourt Mine in Quebec, Quebrada Blanca, and Andacollo Mines in Chile had a record of 245 million pounds in 2001. Located 600 km North of Montreal, Louvicourt Mine is a joint venture between Aur Resources (30%), Teck Cominco (45%), and Novicourt (45%). Aur Resources is the mine operator with 280 employees working to produce a copper and zinc concentrate. In operation since 1994, the mine has produced a total of 12,606,000 metric tonnes of ore grading 3.6 % Cu, 1.5 % Zn, 26gr./m.t Ag, 0.9gr.m.t Au. This highly mechanized mine reached full production in August 1995 at 4,000 tpd. From 1996 to 2001, the average mine production rate was more than 4,300 tpd. The Louvicourt Mine continued its record of solid performance in 2002 and is expected to continue to do so for the balance of its 2.5 years mine life.

May 1, 2003

By K. Izumi

Ultra-grain refinement and high strengthening of metals by accumulative roll bonding (ARB) was widely reported. However, applications of ARB to magnesium alloys were rather limited. In this study, Mg-9%Li-1%Y sheets were applied to ARB at room temperature. Six 0.5 mm thick sheets were stacked and reduced into 0.5 mm thick by four passes. The procedure was repeated up to three cycles, so that the equivalent strain of 6.2 was applied. The sheets show dual phase structure with a (hcp) and ß (bcc). Grains elongates to the rolling direction with increasing number of ARB cycles. After three cycles, fragmented a grains with average size of about 300 nm are uniformly distributed. After the first cycle, the ultimate tensile strength increases to 180 MPa from 133 MPa, while the elongation decreases, however, still high (26%). The tensile strength slightly decreases by the second cycle and does not change at the third cycle. Meanwhile the elongation increases by the second cycle and the sheets show 41% of the elongation after the third cycle.

Jan 1, 2006

By Frédéric Bélanger, George P. Demopoulos, Pascal Coursol, Thomas Feldmann

"The use of scandium in industrial applications is expected to rise in the coming years, in large part due to the expected adoption of new, clean energy technologies such as solid oxide fuel cells or Sccontaining high strength aluminium alloys. Given that the supply of Sc is currently dominated by only a few countries (Russia and China) other sources for scandium extraction need to be investigated. This paper looks at different options for the recovery of scandium from waste solutions generated during the production of TiO2 pigments via the chloride process route. In particular, a direct solvent extraction (SX) approach and possible options for concentrating scandium before the SX step were investigated. It was found that the presence of Ti during solvent extraction causes severe formation of stable emulsions, which can complicate the successful application. This was particularly a problem after multiple contacts of the organic phase with fresh aqueous phase. On the other hand it was noticed that the presence of certain elements in the solution, e.g., iron, could possibly be utilized to concentrate scandium in a solid precipitate.INTRODUCTIONMany newly developed high-tech products depend on the use of chemical elements that are only produced in very small quantities. This can result in high and fluctuating prices, as can be seen from Figure 1, which may cause substitution with inferior alternatives, if possible at all (Reck & Rotter, 2012; US Dept. of Defense, 2013; Whittaker, 2011). One example is scandium (Sc) a member of the extended rare earth element family. There are only a few scandium ore deposits, but most Sc is produced from the processing of by-products of other metallurgical processes (Melcher & Wilken, 2013). Increasing demand for scandium metal and oxide (Sc2O3, scandia) is coming from its increased use in applications such as ceramic lasers (Li, Ikegami, & Mori, 2005; Rainer et al., 1982), high strength aluminium alloys (Lathabai & Lloyd, 2002) as well as solid oxide fuel cells (SOFC) (Thijssen, 2011). Especially, the spread of climate friendly SOFC’s, which are a commercial product today (Bloom Energy, 2014), is expected to be a main driver for future Sc2O3 demand. However, the rate of market penetration of this green technology depends on the availability of high purity Sc2O3 (>99.999%), since it specifically contributes to longer life-time and better safety of the SOFC’s (Bloom Energy, 2014; Irvine, Politova, & Kruth, 2005)."

Jan 1, 2016

Project Details ? Located 420 km northeast of Yellowknife, Northwest Territories ? Jericho kimberlite discovered in 1995 ? Feasibility study showed +3,000,000 carats recovered from 2.6 million tonne reserve ? Nine year mine life ? Approx. 100 person workforce in full production ? First mine for Tahera, First new mine for Nunavut Completed Ambitious Construction Schedule During 2005 o Feb ? Mar/05 Winter road mobilization o Mar ? Dec/05 Pre-stripping, earthworks o Mar ? Apr/05 Camp facility, occupied May 3 o May ? Dec/05 Process plant o Jun ? Dec/05 Maint. shop, fuel storage, power plant o Jan ? Mar/06 Commissioning, start-up o April 2006* COMMERCIAL PRODUCTION

May 1, 2006

By I. Haskett

ABSTRACT The Redwater pool, in north-central Alberta, was discovered in October, 1948, and at the end of 1950 was about 85 per cent developed. Production is from a Devonian coral limestone reef and is found at an average depth of 3,150 feet. The pool has an estimated .productive area of 37,000 acres, and a maximum oil zone thickness of slightly over 200 feet. Wide variations exist in both type and values of porosity, with the average value determined for the reservoir being 6.16 per cent. The total stock tank oil in place is about 1.24 billion barrels. The crude has a saturation pressure of 485 psig, com-pared to the original value of 1,050 psig for the reservoir, and the principal recovery mechanism so far has been the natural water drive. Cumulative production to January 1st, 1951, has been about 15.5 million barrels. These withdrawals resulted in a reservoir pressure decline of slightly over 100 psi. Predictions of future behaviour indicate that the water drive will not be of sufficient magnitude to maintain the reservoir above saturation pressure past 1953, and that, with natural depletion, the pool will be produced largely by a solution gas drive. Pressure maintenance by water injection has been considered and the possibility of raising the pressure to the original value of 1,050 psig is also discussed. INTRODUCTION WITH the discovery of the Lewduc pool, early in 1947, the Devonian limestone became the major geological formation contributing to Western Canada's rapidly growing petroleum reserves. Redwater, discovered in October, 1948, is now the largest known Devonian pool in Canada, with a recoverable reserve estimated at approximately 500 million barrels. Until recent years, the knowledge of the nature and characteristics of this type of limestone reservoir has been comparatively limited.

Jan 1, 1951

By W. E. Lockley

This paper will attempt to answer a number of questions which are important to the safe and continued operation of an electric power system. 1. WHY should electrical protective devices be tested? 2. WHAT devices should be tested ? 3. WHEN should they be tested ? 4. HOW should they be tested? 5. WHO should test them ?

Jan 1, 1977

By David K. Fountain

"The growth of the mining industry in British Columbia in the last ten years has been largely the result of the development of large low-grade copper and molybdenum deposits. There are two problems which must be solved in the search for mineral deposits of this type. It is necessary to detect large volumes of rock containing a low percentage of total sulphide mineralization1 and, secondly, to get some idea of the economic significance of this mineralization. The standard geophysical exploration techniques available have a varying degree of application in the search for disseminated sulphide de-posits. The electrical methods, and the induced polarization method in particular, are the most successful direct methods, and magnetic methods have indirect application in most situations. This is illustrated by geo-physical survey results from several properties in British Columbia."

Jan 1, 1968

By C. -K. Fang

"Aging effect on the wear resistance of alumina particulate-reinforced 6061 aluminum matrix composites with a block-on-ring wear tester has been investigated. Specimens with various Al2O3 volume fractions of 0%, 10% and 20% were employed in this work. Experimental results indicated that over-aged monolithic 6061 Al had the best wear resistance, as compared with under-aged and peak-aged conditions. For the composite containing 10% Al2O3, over-aging and peak-aging resulted in similar wear resistance, which was higher than that for underaging conditions. For the composite containing a high volume fraction (20%) of Al2O3, the wear resistance reduced with the increase in aging time. Although longer aging time was favourable to the wear resistance of monolithic 6061 Al, it was detrimental to that for the Al2O3/6061 Al composite with high volume fraction of particles. IntroductionMetal-matrix composites (MMCs) have received attention in many engineering applications because of the demands for high specific strength (strength-to-weight ratio) and specific stiffness, good high temperature capabilities and wear resistance. The manufacturing processes of fiber-, whisker-, and particulate-reinforced MMCs have been well developed (Hosking et al., 1982). Because of the reduction in fabrication cost, the applications of MMCs have been widely extended to light weight-bearing sleeves, calipers, automobile parts (brake rotors, drive shafts, connecting rods, piston rings, and cylinder liners), sporting goods, aerospace components, tanks (wheels, speed brakes, and track shoes) and other industrial applications. Among the three types of metal matrix composites, particulate-reinforced MMCs are promising because of their homogeneous and isotropic material properties and low cost. Additionally, they can be formed using conventional metal processing techniques."

Jan 1, 2003

By A. E. Flynn

THERE is at the present time a revived interest in amalgamation, due to the number of mines starting up, usually on high-grade ore, and utilizing this relatively cheap and convenient means of recovering gold, more especially in their initial stages of production. The marked increased use of the amalgamation process has revealed a dearth of amalgamators and there is no doubt the art of amalgamation has stood still for a generation or two and is not readily applicable to the modern practice of milling gold ores. Mill operators of long experience are learning the art for the first time and are giving it intelligent study, and considerable testing and research work is now being undertaken Most millmen consider amalgamation a simple process, and so it is when we have a clean ore with coarse gold, specially when stamps are used for crushing. In treating Nova Scotia ores by stamps and amalgamation, recoveries of 95 to 97 per cent are common and easily obtained. So-called 'under-water feed' is almost universally used in Nova Scotia and is quite beneficial. The water is supplied through jets between the dies and below the die surface and maintains this space as a live trap which catches the gold particles before they are overground and spoilt for amalgamation. With this method, the portion of gold recovered in the battery is higher than usual and often amounts to 80 per cent of the total gold in the ore, the remaining 20 per cent being caught on the plate. As a continuous amalgamator, the simple plate cannot be excelled. Some of the modern devices having moving or covered and not very accessible plates, which cannot be readily inspected and dressed to keep them in condition, do not give the best results in service. An exception might be drawn in the case of amalgamation of very heavy ore or concentrate which would bank up unless the plate is carried at such a steep inclination as to weep mercury. Difficulties in stamp-mill amalgamation are encountered when acid water is used or when grease is present. Also, certain sulphides and graphitic and talcose ores give trouble, resulting in poor gold recovery and high mer-cury loss. The older literature on gold milling deals with the common troubles of this type and the old-time amalgamator was well able to take care of day-by-day difficulties. When the difficulties were unsurmountable, the ore was classed as 'refractory' and other processes were used.

Jan 1, 1939

By Knud Sinding

Mining firms are widely criticised for their adverse impacts on the environment. At the same time many firms in the industry devote extensive resources, both financial and managerial, to the reduction or elimination such impacts. Very considerable improvements have been made, although these are sometimes overshadowed by a few high-profile accidents, such as the occasional collapse of a cyanide-containing tailings dam. In parallel, much effort is also directed at projecting a positive environmental image, as witnessed by extensive environmental reporting, both on paper and increasingly through web-platforms. Mining projects today almost invariably involve some form of environmental protection. In industrial countries regulations in this area are extremely stringent, as is enforcement. In less well developed countries, regulation and enforcement may be weaker, but firms are in many cases and for a number of reasons committing themselves to high levels of environmental protection, even if they might get away without doing so. Research in the area of environmental performance of mining firms has so far paid much attention to concepts such as sustainability indicators and the sustainability of individual firms. Given the still raging debates about the appropriate way to determine the degree to which any given firm is sustainable (Welford 1995) as well as the usefulness of what will in the final analysis be a value judgement, anyone on the sidelines of the debate will come back to the fundamental issue, how is knowledge that a particular firm has been judged ?sustainable? going to be made use of. This issue remains unresolved, which may explain the lack of progress in formulating a useful definition of a sustainable firm The question addressed in this paper is not so much about what firms are doing on the ground or in any particular case of environmental protection, but more in the subsequent use of these efforts - and by extension - on the overall direction of corporate environmental strategy. The fundamental problem facing all mining firms is that they cannot easily benefit from unilaterally reducing their environmental impact. The firm can of course avoid liability and keep a variety of stakeholders happy and hence experience lower costs of obtaining the [input] resources they need (in a broad sense, not just minerals), but this represents only part of the opportunities available form pursuing an environmental strategy (Reinhardt 2000). The other part, which may have an enormous potential, involves the concepts of competitor management and product differentiation. The logic of keeping stakeholders happy has been most forcefully argued by Pfeffer and Salanchick (1978) who link the behaviour of firms in all domains to their ability to obtain the resources they need, at a cost that is lower than it would otherwise be (Pfeffer & Salanccik 1978). Several varieties of strategy can be included under this heading, including cost reduction and risk management. The alternative logic is to convince customers that they want to pay more for minerals supplied by mining firm X or directly attributable to mine Y, or by making all mineral users pay more. These two strategies, which may be referred to as product differentiation and competitor management, respectively (Reinhardt 2000) are related to the demand side of mineral supply, whereas cost reduction and risk management are related to the supply side. Mining firms have not pursued the demand side very much, if at all. This is probably due to the extreme difficulty of moving mineral products, bulky and unglamorous as they are, away from their

May 1, 2003

Discovery of an economic diamond deposit produces considerable wealth in terms of jobs, royalties, mining investment, and economic spinoffs for residents, including Aboriginal peoples. Diamond mines contribute to the GDP, increased personal income per person and reduced unemployment rates. Is it possible in Alberta?

May 1, 2008

"The most widely used method for predicting the onset of continuous caving is Laubscher’s caving chart. A detailed examination of this method was undertaken which concluded that it had limitations which may impact on results, particularly when dealing with stronger rock masses that are outside current experience. These limitations relate to inadequate guidelines for adjustment factors to rock mass rating (RMR), concerns about the position on the chart of critical case history data, undocumented changes to the method and an inadequate number of data points to be confident of stability boundaries.A review was undertaken on the application and reliability of a numerical method of assessing cavability. The review highlighted a number of issues, which at this stage, make numerical continuum methods problematic for predicting cavability. This is in particular reference to sensitivity to input parameters that are difficult to determine accurately and mesh dependency.An extended version of the Mathews method for open stope design was developed as an alternative method of predicting the onset of continuous caving. A number of caving case histories were collected and analyzed and a caving boundary delineated statistically on the Mathews stability graph. The definition of the caving boundary was aided by the existence of a large and wide-ranging stability database from non-caving mines. A caving rate model was extrapolated from the extended Mathews stability graph but could only be partially validated due to a lack of reliable data."

Jan 1, 2003