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Vale Inco?s Coleman Mine 153 Orebody is a narrow vein deposit with a dip that varies from 30 to 70 degrees. It has a strike length of 1200-feet and the current mining extends from the 4250 level to 5100 level. The primary mining method is mechanized cut-and-fill although drift-and-fill is also used in wider sections of the ore zone. The ore body is divided into six main mining horizons with an average of three mining blocks on each cut. There are some interesting rock mechanics challenges related to mining upward from the 4550 level and these challenges are increasing as the mining front progresses toward the 4400 level. The mining of the 4550 block is currently at cut 13 whereby the crown pillar thickness is approximately 60-feet. Significant factors including increased stress levels in the crown pillar, the change in the orebody dip at this level and a recently indentified geological structure in the footwall, have all combined to introduce seismic activity in the footwall of 4550 level. Closer studies revealed a consistent trend of seismicity that was further examined with core logging and Acoustic TeleViewer technology. The data from these assessment tools disclosed a geological structure that is influencing the mining environment. This paper reviews the seismic analysis for the 4550 level mining zone and the subsequent procedures used to locate the new geological structure. The paper also discusses the key mining practices used to successfully mine cut 13 of 4550 level and briefly reviews the studies that are underway to up-date the mine design for continued extraction of high-grade ore in a safe and productive manner.

May 1, 2009

By J. A. King, D. A. Knight

"The Porgera orebody is located in mountainous terrain in Enga Province, Papua New Guinea. An underground mine has been developed which produces up to 2000 t/d of ore grading over 2 ozs Au/t. Some 79% of the gold in the ore is free, with the balance in a highly refractory form as sub-microscopic gold evenly disseminated within a pyrite matrix.This paper describes the metallurgical plant that uses flotation and cyanidation circuits to effectively recover the free gold in the ore feed, allowing for wide variation in the gold head grade. The refractory gold component in the ore is stored as leached pyrite flotation concentrate and this concentrate will be later treated by autoclaving techniques to recover the contained gold.The ProiectThe property is located in the Porgera Valley 600 Km North West of Port Moresby. The remote location is 2500 m above sea level. The mine area has 3600 mm of annual rainfall and a temperate climate with temperatures ranging from 10° c to 22° c throughout the year.Alluvial gold was reported in the Porgera area in 1938 and has been an important source of revenue for the area for many years. Intermittent exploration was carried out until the 1960 1 s when Placer (PNG) Pty. Ltd. with Mt. Isa Mines commenced an extensive exploration program. The property was brought to production in 1990 by the Porgera Joint Venture group consisting of Mount Isa Mines Ltd, Rennison Goldfield Consolidated Ltd. and Placer Dome Inc, each with a 30% ownership and the Government of Papua New Guinea with a 10% share. Placer Dome Inc. is the manager of the property with construction under the direction of the Placer Dome Technical Services group."

Jan 1, 1992

By Vu Van Dong

Resource estimation is the science of determining the amount and quality of a given material in the ground that has the potential to be mined at a profit. This is because during this time computers have become more widely available and more powerful and software packages have become more comprehensive and user friendly. Over the past three years The Mining Geology Company with the support from Vinacomin Group has developed the Coal Geological Modelling and Reserve Estimation ? VMG system. The VMG system enables the geological and mining engineer to start at the reserve estimation for the mine design and planning. The VMG system enables the national and international standards (NI43-101, CIM-Canada; SAMREC Code, Africa, and JORC Code, Australia) and user friendly with menu driven thereby permitting the engineer with minimal computer training to rapidly learn and utilize the system. Geological and mining data input through digitized map files and drill-holes information files stored in the database that is an integral part of the VMG system with the main function for collection, validation, and recording, storing and processing of data will include both ?primary? (observation and measurement) and ?interpreted? data. It is recommend that data be stored digitally, using a documented, standard format and a reliable storage medium that allows for easy and complete retrieval of the data. The coal reserve estimation through standard polygon methods with the increased use of these mathematical techniques (geometrical modelling, geostatistical method, least square method, ?) over the last ten years corresponds, to some degree, to a decrease in both the amount of the coal deposit mapping and, in particular, coal seam structural interpretation and modelling, and permit rapidly evaluation of coal seam and overburden quality and quantity. The understanding of the relationship between the coal mineralization of interest and the likely related complicate geological processes and structure that govern its emplacement and geometry within the geological framework is essential to the establishment of the geological controls for coal mineralization. System outputs includes: drillholes summary reports, stratigraphy, cross-sections, isopach maps, structure, contour maps, premining and post mining topography maps, and 3D perspective view on coal seam structure.

Oct 1, 2009

By R. Stach, S. Gola, P. Zgrzebski, K. Soroko

"The future of Polish copper mines KGHM Polish Miedz S.A. will be associated with mining at depth. At present, technologically advanced measures are being introduced to minimize the adverse influence of the environmental hazards on people working underground. Polkowice-Sieroszowice mine is the only mine in Poland where mining takes place in copper and salt deposits. On the basis of the current and anticipated methods of ventilation of a selected ore deposits the paper will analynze a number of solutions enabling planned mining of copper ore deposit, while minimizing the impact of natural aerological hazards in working areas. INTRODUCTION The future of copper ore mining, carried out by KGHM Polska Miedz S.A., will be based on mining from continuously greater depths (Butra, 2015). It is forecast that this will be accompanied by an increasing climatic hazard, resulting from an increase in the original temperature of rocks of more than 45°C as well as gas and geodynamic hazards (Soroko, 2015; Andrusikiewicz, 2015). Due to the safety of underground teams, a need arises to develop methods eliminating the adverse impact of the natural hazards, down to a level enabling the mining activity to be carried out on an industrial scale while maintaining favourable economic parameters. Current depths of the copper ore deposit being developed are effectively verifying the technical methods and measures employed to date for eliminating the natural aerological hazards. Amounts of air supplied to mining areas, with lengthy transport routes, are becoming insufficient for miners’ temperature safety, whereas increasing the power of cooling air-conditioning stations for cooling the air undermines the economic legitimacy. However, along with the temperature hazard, a significant problem at the current depths is an increase in gaseous occurrences in the headings’ areas. The concentrations of natural harmful gases found, even with the values below the permissible concentrations, in the case of limited amounts of air and/or low airflow rates, may pose a considerable danger to the workers. The hazards referred to are currently the major factors determining the advance of headings, above all in mining sections, being the outcome of geological structure and depth of lying of a deposit. However, at the current depths of mining minerals from deposits, room-and-pillar mining systems employed also have a decisive impact on the increase in natural aerological hazards."

Jan 1, 2019

By C. Villaseca, F. Penna, R. Villarroel

Acid mist is the undesired result of copper electro-winning (EW) process, generating a contaminated and hazardous environment in the working areas, as well as promoting high corrosion conditions for structures and equipment in the EW tank-house due to the buoyancy of sulfuric acid in aerosol form. Likewise, organic entrainments that occasionally occur in this process contaminate the cathodes, as well as increasing the risk of fire. LateralVex® and LateralFlow® are technologies that effectively and efficiently solve these problems, without affecting the usual activities of the operators, thus presenting a significant distinction with respect to other technologies that seek to solve these problems. Minera Antucoya, an AMSA group company, which produces 80,000 tons of electrolytic Cu per year, decided to install both technologies for its EW tank-house, LateralVex® in commercial cells and LateralFlow® in scavenger cells to keep both the acid mist and the organic entrainments under control. This paper presents the effects of applying these technologies in Minera Antucoya’s electro-winning plant, the challenges addressed, the difficulties encountered, the problems and opportunities that their implementation involved, as well as the surprising results obtained at the time of measuring the acid mist— less than one hundred’s part of the Allowed Weighted Limit—in samples taken with the plant operating at maximum current capacity. Additionally, the paper includes some of the improvements identified during the period, more than 3 years, in which these technologies have been in operation in Minera Antucoya. INTRODUCTION Electrowinning is the most used electro-chemical process in the hydrometallurgical industry for the recovery of highly pure metallic copper as its final product, which is formed in previous stages in an aqueous medium that goes through a selective process using organic solvents to separate impurities and concentrate the metal in a sulfuric acid solution. In the last stage, this solution goes through a process in which high- density current at a low voltage is applied, so that the metal in the solution will deposit in solid state on a plate, usually a stainless-steel plate. This last process involves the generation of other sub-products due to the electro-chemical dissociation of the electrolyte’s components, or to the addition of chemical additives, or due to specific physical conditions or lack of controls during the operation.

Jan 1, 2019

By J. Ambrose, R. W. Zimmerman

"Shales are highly anisotropic in their mechanical behavior. The strength ( ??1) of anisotropic shales depends not only on the magnitude of the other two principal stresses ( ??2, ??3), but also on the bedding plane orientations (?) relative to the principal stresses. In this study, the role of the intermediate stress ( ??2) on the strength of shale is evaluated using new data from triaxial compression and extension tests. To understand the failure behavior of shales, we have carried out triaxial compression tests ( ??1 > ??2 = ??3) on two organic rich mudstones, at different confining stresses and loading angles. We first fit the triaxial compression data with Jaeger’s plane-of-weakness model, and find that the model is able to represent the strength behavior of anisotropic shales reasonably well. We then carried out five triaxial extension tests ( ??1 = ??2 > ??3) for a high strength-anisotropy shale, and two extension tests for a low strength-anisotropy shale. Results from the compression and extension tests for failure along the weak plane shows that the role of ??2 is not significant for weak plane failure. However, for the low strength-anisotropy shale, the failure strength of the intact rock (i.e., at ??= 0o and 90o) for compression and extension tests were significantly different. This indicates that for intact rock failure, the role of ??2 is important and cannot be ignored.INTRODUCTIONFor many years, various researchers have studied the roles of ??2 for failure of isotropic rocks. (Mogi, 1967 and 2007; Colmenares and Zoback, 2002; Al-Ajmi and Zimmerman, 2005 and 2006; Haimson, 2009; Ma and Haimson, 2012). The findings from these studies show that the effect of ??2 on the strength of isotropic rocks is generally significant, and cannot be ignored.Since the role of ??2 in the failure of isotropic rocks was recognized, other researchers attempted to extend some of these isotropic failure criteria to anisotropic rocks, but with limited success (e.g., Tiwari & Rao, 2007; Singh et al., 1998; Zhang and Zhu, 2007; Pei, 2008). Smith and Cheatham (1980), on the other hand, conducted true-triaxial experiments on the Green River Shale and used a J2-I1 type relationship to predict the strength behavior, but without considering the effect of the three-dimensional orientation of the weak plane on strength. Therefore, unlike for the case of isotropic rocks, additional studies need to be done to determine the role of 2 on the failure of anisotropic rocks."

Jan 1, 2015

By M. Nzotta, L. Teng, S. Seetharaman, A. Chychko

The objective of the present work is to optimize the EAF practice towards Mo alloying with maximum retention of the alloying element in molten steel. During Mo additions, there were significant losses to the dust (ca 7 %) and to the slag phase (ca 2 %), which had serious economic and environmental impacts. The present work was aimed at designing a suitable Mo precursor, an alternative to ferromolybdenum, as the Mo source and a process sequence for optimal retention of Mo in the steel. The design of the Mo source should be in such a way that low cost raw materials such as MoO3 concentrate have to be used, stable during the addition so that the vapour phase losses as MoO3 are kept minimum and the dissolution of the precursor in molten steel is easy without loss to the slag phase. After thermodynamic considerations, three precursor materials were chosen, viz. CaMoO4, MgMoO4 and Fe2MoO4. Synthetic mixtures of the component oxides in each case as well as pure MoO3 were investigated by TGA and high temperature XRD in order to find out the temperature range in which the compounds were formed. Experiments were also conducted separately where the evolved gases were analyzed. All the three precursors were formed easily and the loss of MoO3 to the vapour phase was found to be extremely low. Addition of the oxide mixtures to steel melts were conducted in three different scales, viz. 16 g, 500 g and 3 tons (induction furnacle). Initial experiments showed that MgMoO4 was not suitable since the Mo yield in the steel melt was not very high. Fe2MoO4 was found to perform best, the Mo yield reaching 98 %. Further trials were conducted in the 65 ton Electric Arc Furnace (EAF) at Uddeholms AB in Hagfors. Mixtures of mill scale, MoO3 and carbon in suitable proportions were added in a pre-determined addition sequence. It was found that, in the actual practice, the Mo yield reached 99 %, equaling in performance the addition of ferromolybdenum. The process offers an effective use of cheaper raw materials and very high Mo yield avoiding a pre-treatment step like the production of ferromolybdenum. This is both cost effective and environmentally advantageous. The process has been patented and is being currently implemented at Uddeholms AB, Hagfors, Sweden.

Jan 1, 2011

By Ursula M. Franklin

Old iron nails are one of the most common objects which entice the general public to ask questions about the history of metallurgy. There is a lot of history in old nails - history of the manufacturing industry, and social and economic history. Nails, therefore, are fine teaching tools; whether students have to acquire metallurgical skills or explore the structure and properties of wrought iron, whether they want to look into the history of inventions and the development of machinery, studying nails tells a story better than any teacher or any book. I have used this approach often and the following note is based on several student projects, particularly the work of Carmina Herrero and Vicky Marchant. Nails, those essential metallic fasteners, have long been with us. Their size, shape and design is basically a compromise between the makers' ability to control and manipulate material and the demands of the intended application. There were copper and bronze nails in antiquity, but in this paper I want to deal only with iron nails. In Rome, iron nails were common, and Cleere carried out the fine metallographic investigations on a large stock of nails recovered from a Roman fort site in Scotland. Those nails were hand forged; sorting them at the site on the basis of length, shape of head and shape of shank (in cross section) indicated that there seemed to have been some nail standardization. It appears that the Roman smiths used a series of heading dies starting with a 1/s-in. size. Each successive size increased by approximately 1/16-in. The metallographic inspection of the microstructures of the nails showed that the smaller nails were made in the one operation; i.e. both the tapering and the formation were accomplished on the heated rod without reheating. However, in the case of the larger nails, the nail had to be reheated for the tapering after the head had been forged. Most nails were tapered on all four sides of the shank and the shanks were square in cross section; only one group had rounded shanks. Most heads were flat disks, but in one group the heads were pyramids and another group had conic heads. Figure 1 shows the procedure used to produce the pyramidal heads. Obviously, Roman nail making was sophisticated and each nail design was meant for a particular use.

Jan 1, 1999

By Gilles Carrière

"The Huntingdon mine of Quebec Copper Corporation is situated 3 miles south of the village of Eastman, in the Eastern Townships of Quebec. The copper deposit consists of several pyrrhotite-chalcopyrite replacement bodies or bands.The first mining operations on the conspicuous surface gossan of the Huntingdon deposit started in 1865. They were suspended in 1883. The .mine was again active from 1890 to 1893 and from 1912 to 1924. These operations were carried to a depth of 500 feet, and it is estimated that some 150,000 tons of ore were extracted, of a grade reported as varying between 3 Yi and 7 per cent copper.In 1950 a program of exploration was initiated in the area of the old mine, and resulted in the finding of 500,000 tons of ore with a grade of 2 per cent copper. A new shaft was sunk to a depth of 1,160 feet, and by February 1954 the mine was extracting 800 tons of ore daily.General Geology and StructureThe mineralized zones are on the west side of a band of altered volcanic rock, locally called andesite, adjacent to a sill-like body of serpentinized peridotite which lies west of the andesite. The bands of andesite and serpentine extend several miles north and south of the mine. Their strike is generally north 15 degrees east, and they dip steeply east. Their widths vary very considerably along the strike, but in the mine area each is about 450 feet wide on surface. They are enclosed in sediments of the Caldwell series, consisting of greywackes, quartzites, slates, and shales. The andesite belongs to the same series, which is thought to be of Cambrian age (1). The ultrabasic intrusive is post-Ordovician.At p\aces along the serpentine contact the andesite shows a pronounced schistosity; it is parallel to the contact and rarely extends farther than a hundred feet from it. No evidence of strong folding or faulting has been found so far in the mine workings. Some apparent distortions and irregularities in the strike of the contact may all be due to the intrusive nature of the serpentine. In the mine area, transgressive tongues of serpentine point southward in the andesite.A few vertical lamprophyre dykes, not more than five feet thick, cut the other formations at right angles."

Jan 1, 1949

By W. P. Corking

"The purpose of this paper is to describe the relationship of the goldbearing ore to structure at the Pickle Crow mfoe. Information beyond this scope may be found in the reports and papers of Hurst( l), Bothwell(2), Thomson(3) , and Monette( 4).The property lies on Crow river, in Patricia district, 80 miles northeast of Allanwater, and about 125 miles northeast of Sioux Lookout on the Canadian National railway. From April of 1935, when the mill began operation, to the end of 1944, a total of 564,890 oz. gold and 49,275 oz. silver were recovered from 958,416 tons of ore.Mining on the property is at present carried on in two separate orebodies, the Howell and the No. 2 vein. Stoping has been carried on from every level on the Howell vein to a depth ot 2,450 feet below the surface and from several levels on the No. 2 vein through a mile long cross-cut on the 750-foot level to the Howell vein workings. A steadily increasing volume of ore is being obtained from the No. 2 vein.Each of the two orebodies consists of vein quartz with small amounts of other gangue minerals either in a single vein or a stockwork of veins. Both lie within sheared walls and carry gold in the free state. Fig. 1 shows the position of the veins with respect to the surrounding rocks. It will be noted that the delineation of the beds of iron formation shows that the lava flows and minor, interbedded sediments that make up most of the country rocks are areally folded and contorted.STRUCTURENearly all gold found to date in sufficient quantity and concentration to make ore in the Pickle Crow area is confined to these major quartz veins . Both strike a little north of east and dip north, and in both cases the attitude of the enclosing rocks is somewhat more north of east in strike and more steeply north in dip than that of the veins. As a result of this disposition both veins migrate across their enclosing rocks at a moderate angle in both dip and strike. (In this connection it should be noted that No. 2 vein dips at a considerably flatter angle than its host rock, but has a very pronounced rake to the northeast, effecting the same result as in the Howell vein.)"

Jan 1, 1954

By Evelynn Stirling

"The paper/presentation will review the evolution of diesel technology from older diesel engines (1990 vintage) through to the latest technology as a result of the ever changing emissions regulations. It will encompass the EPA Tier levels as well as the latest Euro Stage V emissions. The next step with technology will be to address the CO2 emissions, which translates to improving fuel efficiencies of the product as well as other technologies like battery electric, hybrid and fuel cells. As technology progresses it also becomes important to improve connective diagnostic systems to support maintenance practices and improve efficiencies. What will also be presented will be the key emissions changes to the different gaseous and particle mass elements as the products have transitioned from the EPA Tier 3 through to Tier 4 Final regulations. Offering a range of different technologies to the underground mining market matters as not all pieces of equipment will perform optimally due to its duty cycle and application. INTRODUCTION Rudolf Diesel built his first well-known prototype of the high-compression engine in 1897. Since that time, the diesel engine has evolved into one of the world’s most capable and reliable forms of power generation. Diesel engines can be found in a wide variety of vehicles and equipment, powering everything from agriculture and construction equipment to power generators and marine vessels. In the early days the emissions from diesels was very poor and extensive work has been accomplished over the decades to make the product more environmentally friendly. This is more important in underground mining where the space is limited and ventilation is expensive and challenging. DISCUSSION The key driver of the development of diesel technology is the legislation globally around engine emissions. The emission level requirements over the years has forced diesel engine manufacturers to build a deep technical understanding of the system and how to innovate and optimize key elements of the engine. Cummins expertise has been built over the years as the diesel engine has evolved from a relatively simple mechanical engine to an electronic system with advanced air handling, fuel system, after treatment, and controls. Cummins has also continued to expand into systems beyond diesel, including natural gas. Many new components have been added to diesel engines to reduce emissions while improving fuel efficiency and reliability and, at the same time, reduce the total cost of ownership to the customer."

Jan 1, 2019

By Dougla McDonald, Richard Poulin

"Most mine managers in Canada today will agree that one of the keys to mining efficiency and productivity is their human resources. A5 a result, many mines develop some sort of incentive designed to tap their employees' capabilities to the fullest extent. Historically, the most common plans used have been ""piece-rate"" plans, where individual or small groups of miners are paid a financial bonus based on some measure of their productivity. Recently, however, incentive plans that take a more team-based approach have been developed in some Canadian mines. One such plan will be defined in this paper, and its popularity in the industry today discussed.Gainsharing PlansThere are two primary components to a gainsharing plan. The first is a cash incentive, which is paid to all employees and based on factors that are highly correlated with employee productivity, and key to the profitability of the mine. For example, the typical gainsharing cash incentive is based on the cost/unit of metal produced. Management (in consultation with employees in some cases) will establish the budgeted cost per tonne, and any savings in this amount is shared between the company and the employees. The second is a management philosophy and associated communication network, which is designed to foster an environment that encourages information exchanges, communication, participation, and trust between employees and management. The typical gainsharing communication network consists of two tiers of committees. The first, operational committees, include all employees working in the same department or departments which frequently interact. The employees meet monthly with management personnel to discuss problems encountered and brainstorm for solutions. In most cases, these committees will nominate a person in the group to structure the meeting to maximize its efficiency. The second, the screening committee, is a single group consisting of representatives from the various operational groups, whose primary job is to ensure that the plan is effective, and the objectives and results generated by the plan remain consistent with the mine objectives. In short, gainsharing plans tell employees that their bonus depends upon performance and then gives them the opportunity and incentive to affect that performance. The opportunity is provided by a communication network and positive management practices, and the incentive comes in the form of ""intrinsic"" rewards of participation and the ""extrinsic"" rewards of the bonus payments. Figure I will clarify the relationship between the intrinsic and extrinsic rewards."

Jan 1, 1995

By C. -G. Berg, J. T. Tuominen

Since the beginning of the 20th century, energy efficiency in copper smelting has been improved by a factor of 30 as a result of adopting autogenous smelting processes with more and more efficient waste heat recovery systems, increasing use of oxygen enrichment and countless smaller improvements. Nevertheless, energy in the form of electricity and fuels continues to be the biggest contributor to smelter operating cost. Metallurgists around the world are under constant pressure to find ways to save those precious megajoules wherever they can. One area that is often neglected is the removal of water contained in concentrates. Copper flotation concentrates, as delivered to a smelter, typically contain some 8–12% moisture. This moisture must be removed and the only way to do this is by evaporation, which consumes a lot of energy. Several studies have shown that the most efficient way of removing this moisture is to use a steam- heated indirect dryer—the least efficient way being the feeding of wet concentrate directly into a smelting furnace. Even in the most efficient smelters that employ modern steam drying, the energy needed to remove the moisture from the concentrates constitutes over 15% of the total energy consumption of a smelter – acid plant complex. The major steps that have been taken in the past to lower the energy consumption of moisture removal are the use of drying in general and the adoption of steam drying. The energy efficiency of concentrate drying has been improved by 25% over the last 20 years. The latest giant leap in this area, the Kumera Heat Recovery Dryer, is the result of Kumera’s long-term development in improving the efficiency of concentrate drying. The Heat Recovery Dryer is a novel application of steam drying that uses the waste heat from dryer exhaust gas for drying concentrates, thus, cutting the energy consumption by a further 30%. This paper discusses energy consumption in copper smelting in general and analyzes the energy consumption of concentrate drying in detail. Different dryer types are compared especially from the perspectives of energy consumption and environmental emissions. Applicability of different energy sources for drying is evaluated and discussed. The principle of the Kumera Heat Recovery Dryer is presented along with results from extensive continuous pilot plant tests. Potential applications and the feasibility of Kumera Heat Recovery Drying technology are discussed.

Jan 1, 2019

By K. L. Azinger

Successful relationships between mining companies and local stakeholders are now an essential part of the social contract of “doing business” (Prescott, 1995). The methodology presented in this paper is designed to assist mining companies in understanding and building relationships with diverse stakeholder groups. The methodology starts by recognizing that mining projects have a natural life cycle which can be used to identify when new external affairs strategies are required. In designing an external affairs strategy, the first step is to set objectives that are compatible with the overall objectives of the mining project. The management team then identifies the main stakeholder groups and seeks to understand the priorities and inter-relationships of the individual stakeholders. The result of this stakeholder analysis is an understanding of the Degrees of Influence of each of the stakeholder groups along with a relationship map which illustrates the strong interactions between stakeholders. The company is then prepared to take a proactive approach to building relationships with the primary stakeholders. This methodology was developed by BHP to assist with the federal government environmental approval process for the development of Canada’s first diamond mine. BHP has successfully used the methodology in three different phases of the NWT Diamonds Project and is now applying the methodology to mining and development projects around the world.

Jan 1, 1998

By P. T. O'Kane

The PLATSOL® process, initially developed for the treatment of the NorthMet Cu/Ni/PGM concentrate, has seen over the recent years its applicability extended to include numerous other Cu/Ni concentrates of the same type, as well as other precious metals-containing feedstocks. However, several concentrates were found refractory to the typical PLATSOL® conditions, more particularly so the platinum. Attempts to extend those conditions, such as higher temperatures (250°C), longer retention time, increased oxidation conditions, higher chloride additions, were not successful. Detailed mineralogical investigation of those PLATSOL® leach residues indicated the main refractory mineral to be cooperite (PtS). Further metallurgical investigations showed that a thermal pre-treatment of the concentrate effectively unlocked the refractory platinum minerals for the subsequent leach. Temperatures between 400 and 750°C were tested, with the optimum being found around 650°C. The kinetics of the pre-treatment process were fast, and one hour at temperature proved sufficient. Under those conditions, PLATSOL® extractions were re-established around 95% for both platinum and palladium. From a mineralogical examination of the calcine, it was shown that the effect of the pre-treatment was to transform the cooperite and other refractory sulphides into metallic platinum and alloys, amenable to the PLATSOL®. The implications of the pre¬treatment step for the processing of PGM concentrates arc briefly discussed.

Jan 1, 2004

By Gordon Sproule

THE papers presented to the Institute, and published in the BULLETIN, in the past three years, may be classified as follows: Geology, Mining, and Milling 89 or 58.5 per cent Smelting, Refining, and Refractories 17 " 11.2 " Mechanical and Physical Metallurgy 7 " 4.6 " General (Economics, Welfare, etc.) 39 " 25.7 " Total 152 100 These figure~ should be excuse enou.gh for. the present paper. As indicated by the title it is proposed: I.-To review briefly some of the more recent developments of Physical Metallurgy; and 11.-To show how Physical Metallurgy functions as the link between mining and production metallurgy on the one hand, and consumption engineering on the other hand. Io these days of specialization, papers of the kind being considered mostly gravitate to the American Society for Metals, the American Society for Testing Materials, the Institute of Metals, and the Iron and Steel Institute. In proof that there is a place for the newest and most specialized of these societies, the American Society for Metals, it may be said that in the Montreal Chapter there are 200 active members, and in the Ontario Chapter more than 200. Yet the overshadowing glamour of the mining industry proper, and the publicity it receives, result in an almost continuous dearth of students in metallurgical engineering at our universities. There are more jobs than graduates.

Jan 1, 1936

By P. Schmidt, M. Hopf

Water-cooled parts of submerged arc furnaces are potentially dangerous, especially if molten matte or slag contacts the water. Explosion hazards and metal run-outs generate high costs for production loss and repairs - not mentioning the possible loss of human life. This paper reports about practical results of wear measurement on intensive water-cooled tap-holes and spray-cooled side walls. On the one hand an embedding technology has been developed, that is used e.g. in water-cooled copper tap blocks or copper side wall coolers. Second the application of the sensor installation on the inner side of a water-cooled steel shell will be discussed. The fibre-optic sensor is fed through a specially arranged piping system and measures numerous temperatures over its entire length. By using the thermal conductivity of the installed refractory materials the lining thickness is calculated. The practical installation of the sensors will be discussed and the results of the wear measurement will be compared to the theoretical FEM calculations. The highly sensitive and accurate temperature measurement, as well as the recalculation of the impact of differences in the cooling water temperature, allows the exact determination of the remaining lining thickness. The discussed technologies offer efficient and safe monitoring of tap-holes, side walls and other endangered parts of pyro-metallurgical smelters.

Jan 1, 2015

By J. D. Stewart

One of the first important questions that should be settled on the opening of a mine or the development of a new deep is the system of haulage to be used, since the layout of the haulage-ways at the pit bottom, or, in case of a slope mine, the arrangement of the surface works, depends largely upon the type selected. Should it later become desirable to install a system of haulage of a type other than that for which the mine roadways were originally laid out, considerable difficulty would likely be encountered in its installation and with the result that it would in all probability be most unsatisfactory and expensive in its operations. It therefore becomes very necessary that full consideration be given the haulage problem at an early date in order that the type best suited to the mine conditions and the required outputs can be intelligently planned for. It is sometimes found, however, that no matter how well the mining engineer explores the seam to be developed, or how accurately he anticipates its eccentricities, there will still remain some unrevealed or unsuspected conditions, or shall we say obstacles, placed by Nature to prevent the too easy winning of her treasures and incidentally to frustrate or modify the application of the plan so painstakingly laid down on paper, and to adversely affect the cost estimate.

Jan 1, 1928

By A. E. Soregaroli, H. D. Meade

"The Keystone porphyry molybdenum deposit, located in southcentral British Columbia, is hosted by intrusive rocks of the Cretaceous Mount Lytton batholith and the early Tertiary Keystone quartz diorite stock. The molybdenite mineralization is associated with rhyolite porphyry dikes flanking a large 1300 m by 2100 m breccia complex. Recognition of the potential for the buried molybdenum porphyry system was based on quartz-molybdenite vein fragments within the hydrothermal breccias.The full extent of the molybdenum mineralization is not known. The few deep drill holes along one comer of the breccia complex defines strong metal zoning of molybdenum and associated elements of F, Mn, Zn, Pb, Au, Ag, Fe and W about the molybdenum stockwork mineralization that may be useful for guiding additional exploration. The best mineralization occurred near the base of the deepest drill hole with 0.114% Mo in rhyolite porphyry near the edge of the breccia pipe at a depth of 1350 m.The exploration history of the deposit has been complex, focussing on both porphyry-style mineralization and precious metal veins and stockworks on the periphery of the porphyry system. Exploration to date has defined an attractive porphyry molybdenum system with uneconomic grades at great depth; however, there remains significant potential to define economic mineralization elsewhere in the Keystone porphyry system and adjoining occu""ences."

Jan 1, 1995

By Ellis Thomson

The microscope is now used extensively not only in the examination of solid ore but also in the determination of fragmental mill products. It has therefore become a matter of paramount importance to be able to mount and polish fragmental as well as solid specimens in the easiest and most efficient way, so that the minerals present may be readily determined. In the case of the solid ore the ordinary mount of plasticine set on a glass or metal slide serves for most practical purposes. An improvement on this is furnished by the small brass container inside of which the specimen is mounted in a cementing medium of sealing wax. The latter is the method in use at Harvard University. It has the advantage of uniform height, thus obviating the necessity of a slide of any sort. It is also easily catalogued as the brass holder may be stamped with a convenient series of letters and numbers that will serve as a label. Other advantages of this type are the ease with which any particular part of the section may be re-located, the excellent storing facilities afforded by mounts of uniform size, and the possibility of polishing ten or a dozen sections at the same time by means of a holder which is placed over the polishing wheel, is geared with it, but revolves the opposite way.

Jan 1, 1926