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By B. C. Jago, H. Derbuch

"The Freightrain kimberlite is located on the Brodeur Peninsula, Baffin Island, Nunavut. Twin Mining is exploring the pipe and adjacent land (79 claims/655 km2) using a combination of airborne geophysics, soil sampling, diamond drilling, trenching and bulk sample processing. The pipe originally was discovered by Cominco Limited in 1975, re-evaluated in 1993 by Lumina Investment Corporation, when it was staked as the Zulu pipe, and subsequently covered by three claims in 1998 by Helix Resources who called it Freightrain.The Freightrain pipe coincides with a strong, ovoid-shaped aeromagnetic anomaly. It is the only surface exposure of kimberlite within a 30 km long linear trend of fourteen aeromagnetic anomalies that are up to 600 m in diameter.The pipe is exposed in the crater facies, near the transition into diatreme facies as indicated by the occurrence of pyroclastic kimberlite characterized by abundant olivine macrocrysts, juvenile lapilli and kimberlite autoliths set in a serpentine-calcite matrix. Olivine, Cr-pyrope garnet and chromite are the most abundant macrocrysts; clinopyroxene, ilmenite and phlogopite mica occur in minor to trace amounts. Garnet and chromite harzburgite, garnet lherzolite, garnet-spinel lherzolite and rare eclogite dominate the xenolith population.Garnet and chromite mineral chemistry indicate encouraging diamond prospectivity and that potentially diamondiferous garnet and chromite harzburgite were the principal sources of diamond in the mantle at the time of kimberlite eruption.Single clinopyroxene grains define an ~42 mW/m2 sub-continental geotherm that is rooted in the diamond stability field. This compares to a slightly hotter geotherm (~48 mW/m2) for adjacent Somerset Island kimberlites with an origin in the graphite stability field. This data accords with the general lack of sub-calcic Cr-pyrope garnet, diamond inclusion chromite and diamond in Somerset Island kimberlites."

Jan 1, 2002

By C Lower

An unprecedented, quantitative, deposit-scale understanding of major clay mineral distribution throughout the Yeelirrie uranium deposit has been achieved by adapting the existing HyLogger™/HyChips™ analytical technique to measure resource assay pulps. Spectral analysis via HyLogger™ and HyChips™ systems has previously been used as a small-scale geometallurgical research tool, but never before has it been quantitatively applied to an entire resource sample population for the purpose of developing stand alone block models for major clay minerals. Economic uranium mineralisation within the thin but extensive Yeelirrie?palaeochannel?primarily exists within the transition zone between a groundwater-derived calcrete and the underlying clay-quartz regolith. Early geometallurgical investigations identified that certain clay minerals could be deleterious to the efficiency of the uranium recovery process. Accurate calculation of clay mineralogy from resource assays proved too difficult due to chemical similarities between co-existing kaolinite, smectite and magnesium carbonate minerals. A relatively low-cost, efficient and accurate method of quantitative clay mineral analysis was required to measure over 70 000 resource assay pulps. After initial testing and comparison with QXRD, the HyChips™ 3-1 spectral logging system was implemented as a primary method of clay mineral analysis for the Yeelirrie uranium deposit. The resultant spatial data set allowed the interpretation and geostatistical analysis of geometallurgical domains across the deposit. Clay block models were generated and used in geometallurgical resource calculations to benefit the mine planning process.

Sep 5, 2011

By P. M. May, V. Gella

The deportment and speciation of trace elements during mining and minerals processing is becoming an area of increasing concern with regards to potential health and environment risks. The use of chemical modelling can enhance our basic understanding of the deportment and speciation of trace metals under conditions present in gold processing solutions, and assist in laboratory and field investigations. In this paper, we report the results of chemical speciation modelling using the JESS software package for the trace toxic elements Pb, Cd, Hg, Se and Te in cyanidation solutions of varying salinity and relate the models to experimental data. The speciation of mercury is examined in detail.

Jan 1, 2011

In March 2003, Rio Tinto Coal AustraliaÆs (RTCA) new Hail Creek open cut coal mine commenced operations in the Bowen Basin. Hail Creek is a two-seam strip mining operation utilising two 90 m3 draglines and a fleet of excavators and trucks to remove the overburden. All overburden at Hail Creek is blasted prior to excavation. The mine conducts its own drill and blast operations while engaging Dyno Nobel for the provision of explosives supply and loading truck (bulk explosives vehicle û BEV) services. This arrangement was favoured over outsourcing the entire blasting function to a contractor. Subsequent to a value engineering review, the mine set about developing and implementing a blasting operation that did not rely on the need to store bulk quantities of ammonium nitrate on site. There were advantages identified in doing this, in particular the reduction of capital expenditure required and reduced exposure to a number of recently introduced security requirements. This approach also makes sense operationally. The establishment of reload facilities for the BEV close to the blasting location, where turnaround times are kept to a minimum, increases the productivity of the BEV. For this strategy to be successful the logistics of ammonium nitrate supply into the blasting operations has to be well planned and thoroughly executed. This means a robust planning and forecasting arrangement needs to be established with the supplier and transporters of the ammonium nitrate. To date, 80 million bcm of overburden has been blasted at Hail Creek and each year the quantity of overburden requiring blasting is increasing. The purpose of this paper is to present the findings of a study: evaluating the effectiveness to date of the strategy to conduct blasting operations without ammonium nitrate storage on site, and identifying whether there is a limit to which this strategy can operate after which the introduction of bulk ammonium nitrate storage facilities are necessary.

Jan 1, 2007

By Yi Luo

A massive roof fall occurred in a small room-and-pillar coal mine. The roof falls occurred under a barrier pillar in a closed coal mine located a short distance above the active mine. The extensive fractures connected the active mine with the old mine, turning them into a “combined mine.” Since completely sealing off the roof fall area is prohibitively expensive for the mine, ventilating the connected old mine became the only option. A comprehensive investigation was conducted to understand the atmospheric condition in the old mine and to find an efficient way to ventilate the “combined mine.” A set of studies involving geology, gas content, pillar stability and mine subsidence were performed to explore whether the closed mine is filled with an explosive air-methane mixture. The air quantity measurement data were used to determine the resistance of the air path formed through the fractured zone. Observations and measurements made from a tour to the underground and mine surface enabled the formulation of simple but effective ways to ventilate the old mine. The ventilation network analysis also suggested methods of control, so that sufficient ventilation air can be directed to the two parts of the old mine.

Jan 1, 2010

By L. Gertsch, R. Gustafson, J. Rostami, C. Swope

Development of a permanent human base on the moon for exploration requires a self-sustaining system. Such a system entails the production and processing of limited amounts of raw material on the moon. Any mining and construction activities on the moon can only be performed by a robust excavation machine that can excavate a variety of material, from loose surface regolith to consolidated (frozen) regolith with embedded rocks in the mixture. Meanwhile, a limited amount of information on lunar regolith is available to develop and optimize a machine for lunar ground conditions. Therefore, any excavator designed for use on the lunar surface should have the ability to adapt to a wide range of operating conditions. A prototype cutterhead for the lunar excavator was built and tested at the Kennametal facility in Latrobe, PA. This paper discusses the results of initial material characterization, as well as full-scale tests of a prototype cutterhead in relevant material. A brief review of anticipated production rates under various assumed ground conditions is also presented.

Jan 1, 2010

By Maral Malekian, Pat Bellett, Eranda Tennakoon, Fernanda Carrea, Moe Momayez

Slope instabilities in open-pit mines pose a safety risk to workers and a financial burden on production. The direct impact of slope stability on safety and production makes slope failure predictions one of the important challenges in the mining industry. Predicting the precise time of slope failure has been the subject of much research in conjunction with the development of innovative monitoring technology designed to prevent sudden failures. This paper investigates the use of AutoRegressive Integrated Moving Average (ARIMA) model to predict the time of slope failure. Input data such as inverse velocity (IV) and dimensionless inverse velocity (DIV) from 20 slope failures were used to train the model predict the failure time. For comparison purposes, the time of slope failure using the traditional inverse velocity method is also provided. We show that ARIMA provides 90% more accurate predictions than the TIV approach.

Jul 12, 2023

By John D. Sullivan

In leaching copper ores knowledge of the rate of dissolution of the copper minerals and of the impurities is desirable. With knowledge of these two factors and data as to what minerals are present in the ore the metallurgist has an excellent start on planning a leaching cycle to fit that ore. The rate of dissolution is rather difficult to predict, and the time required to leach a given ore may differ markedly from that required by another ore. The whole study as related to mixed oxidized and sulphide ores is one of relative rates of dissolution of the different copper minerals and the impurities in sulphuric aoid and in ferric sulphate. The aim of leaching is to choose a cycle and strength of solvents to extract a maximum amount of copper and a minimum of impurities. The consumption of reagents per unit of copper dissolved is a function of the strength of the reagents used and the relative rates of attack on copper minerals and impurities. An opportunity may exist of obtaining the kind of electrolyte wanted for electrolytic precipitation and yet of saving on the consumption of reagents by modifying the strength of ferric sulphate and of sulphuric acid during the cycle to fit the time needed for dissolving the sulphide and oxidized minerals present.

Jan 1, 1931

By K. F. Unrug

The method of coal pillar design involves primarily two aspects, the geometry of the pillar and the strength of the coal. However, the strength of the coal has to be emphasized with respect to the entire pillar dimension rather than isolated strength values of coal samples taken and measured from different locations. The presently applied pillar design systems do not specify clearly what the coal sample strength really represents. The intention of this paper is to introduce the concept of seam strength as opposed to the current practice of using coal strength as a prime design criteria in the formulation of pillar calculations. Seams are most of ten composed of multiple layers of coal, partings, and bone in different configurations, changing within the vertical section of the seam even in relatively close locations. The difference in strength between the weakest and strongest component of the coal seam could be as much as five times or more. An experimental approach based on multiple compressive tests performed on coal samples from the Coalburg and the Warfield seams from Eastern Kentucky was undertaken. The analysis of the results lead to the conclusion that for pillar calculations both the weighted mean of the seam strength and the strength of the weakest stratum should be considered rather than the relatively vague aspect of coal strength The design of pillar dimensions based on the above mentioned aspects should assure a more realistic design performance.

Jan 1, 1985

The use of scrapers in mining and earthmoving operations is not new, in fact they are one of the earliest methods of bulk earthmoving. A single machine which can load, haul, and dump material with a minimum of ancilliary support is a highly productive and cost-efficient method of earthmoving. In recent times scrapers have been unpopular due to perceived problems and operational limitations, but the last couple of years have seen a resurgence in the use of scrapers in the Bowen Basin as a primary prestripping tool. The main operational limitation of scrapers is the economic operating range. maximum productivity and lowest cost per bcm is achieved on short leads, as the lead distance increases the cost per bcm quickly reaches and then overtakes that of an truck-excavator fleet. The geometry of a ætraditionalÆ coal mine does not readily allow short leads for prestrip fleets due to the nature of dragline stripping operations. The strip arrangement means that material has to be taken around the end of the pit, meaning a longer haul distance than the actual point-to-point distance between load and dump. This can be alleviated by using pit bridges, however these can cause spoil problems for draglines if not properly planned and have been avoided by many mines. Due to the economic haul distance limitation of scrapers, truck-excavator fleets have become the normal method utilised. Currently more geologically complex mines are opening up, which do not allow traditional down-dip strip mining to occur. Cross-dip mining methods allow for short leads between prestrip loading and dumping areas, hence scrapers and bulk doze are realistic alternatives to a truck-excavator fleet in the prestrip environment. Keeping the lead distance to a minimum a fleet of 657Æs can move material at a very low cost. The other main operational limitation of scrapers is the type of material that can be economically excavated. Hard material can lead to damage to the bowl, free-flowing sand will not readily stay in the bowl leading to reduced load factors. Ripping the material with a dozer prior to excavating can lead to improved loading time, and greatly reduced GET consumption. When considering scrapers for prestrip operations a number of things must be considered: is the lead distance within the economic haul distance? should twin power (push-pull) or single power (dozer pushed) scrapers be used? do I need to rip, what should I rip with? what ancilliary support is required? is there another system already available on-site which is currently under utilised? This paper considers the parameters under which large twin power scrapers are the most effective way of undertaking prestrip operations.

Jan 1, 2003

By FOSTER HEWElT

THE scope of this paper is the description of two districts in Peru in which deposits of vanadium have been found, and the consideration of much laboratory-work that I and others have done to determine the nature of these deposits. It is with regret that I present some of the data in a state of evident incompletion, particularly the analyses of a few of the minerals, which leaves some doubt as to whether the true nature of the minerals is understood. I make no apology, however, since in this case, as in many others referring to ore-deposits, conclusive opinions cannot be stated until a great amount of work has been done, and the deposit has been thoroughly exploited. I believe that the data and the tentative conclusions here presented indicate a unique and interesting condition which may assist others in work along similar lines; and further, what is of more practical importance, stimulate a search for a metal which, though long considered rare, is probably so merely because proper care has not been taken to recognize it. An excellent bibliography on the occurrence of vanadium in nature is given by F. W. Clarke in his paper, Data of Geo-chemistry;1 and in the preparation of this paper I have consulted many of the references contained in the Bibliography of the Chemistry of Vanadium, by M. Moissan.2 A brief review of the subject having special reference to the metallurgy of vanadium is contained in the small book by P.. Nicolardot.3 One of these vanadium-deposits has already been briefly

Mar 1, 1909

By Neil McMillan

"By any measure of common practice, Claude Resources' Seabee Gold Mine in Northern Saskatchewan should not now be operating. Not because reserves dwindled, or grade dropped or prices weakened or technical problems arose, but because a host of unimaginable other problems beset the project, any one of which would normally have led to the mine's failure.The success of the Seabee Mine, and it is extremely successful, is a story of the vision and blunt determination of two men. Neither is remarkable in his own right but each possesses the characteristics which were necessary to forge a highly productive and profitable narrow-vein mine in the midst of the most bizarre and unpredictable events which likely have ever beset a mine start-up in Canadian history.Together, Bill MacNeill, a Saskatchewan born, former bush pilot and Ray Gagnon, a big hearted, hard-fisted, miner with 44 years of experience in Canada's underground, built the Seabee Mine.They didn't accomplish this with brilliant geology, outstanding engineering or nimble corporate manouvering but rather a stubbornness and raw common sense which likely are all too often, ingredients missing in failed projects.The Seabee Mine is 100% owned by Claude Resources, a Saskatoon based company taken over by Bill MacNeill, its current chairman, in 1982. The company is listed on the TSE and produces 1200 barrels of oil per day and about 60,000 oz of gold per year. The company has a strong balance sheet, is very profitable and has 18 million shares outstanding.The Seabee property in Northern Saskatchewan started out like many other gold exploration properties in Canada.It was discovered in the l 940's by what is now Cominco, and, while highly regarded by that company the property sat largely dormant until acquired by Claude Resources in 1985.Claude did what most junior exploration companies would do and went looking for a company with a depth of expertise to joint venture the property.That company was Placer Development who could earn a 55% interest in the Seabee by delivering a bankable feasibility study on the Project by July 1988 and providing financing to production.Placer Development was an excellent company and spent over $8 million dollars on the Seabee over a 3 year period. Unfortunately for Claude Resources, Placer Development merged with Dorne Mines in 1987 and the new merged company, Placer Dome, established a minimum production threshold greater than the 50,000 oz per year which the Seabee appeared capable of supporting at that time. Placer Dome's request for an indefinite extension of the joint venture agreement to allow it to drill off a larger ore body was rejected by Claude Resources and the Seabee Property was returned to Claude in 1988."

Jan 1, 1998

By N McKay, J Vann, W Ware, P Hodkiewicz, C Morley

"Geometallurgy is now recognised within the mining industry as an approach that can both maximise value and reduce the risks associated with resource development. The process of spatial ore variability testing for metallurgical response and the use of quick, inexpensive metallurgical proxies has been well developed in the past decade in industry and the literature, and via various collaborative research programs and laboratories. Technology continues to advance with new techniques such as hand-held analytical tools and automated hyperspectral core scanning, allowing for even faster, less expensive in situ geometallurgical testing.In the current mining industry downturn, a critical frontier of geometallurgy is in its application in short-term geological modelling (ore control) and mine planning, and the associated decision-making. This is the end game at which the hard-won knowledge of orebody variability can be exploited to add near-term value. In order for spatial block models to be fit-for-purpose for such tactical uses, they must be populated with key geometallurgical information and then have workflows that use this richer model as a basis of material allocation to destinations so that the true value of the resource is realised.We envision geometallurgy (geomet) programs designed to add and sustain value at two levels:‘Strategic geomet’ has a long-term strategic focus that actively uses all relevant data that helps predict processing performance such as bench-scale metallurgical tests, mineralogy, geochemistry, ore texture etc (‘the geometallurgical database’) to model spatial ore variability and metallurgical response throughout the life-of-mine (LOM). This will enable better resource definition, more optimal mine planning and scheduling, improved process design and sustaining capital strategy over the LOM. The value-realisation is gained by basing all these strategic decisions on spatial models that better reflect the actual value of blocks (or aggregates of blocks) in the model.‘Tactical geomet’ has a short- to medium-term tactical focus that, again, actively uses the geometallurgical database, but also includes new data derived during ore control activities (such as drilling and sampling) to inform allocation-to-destination decisions via the ore control process. This will enable improved efficiency (ie less error) in allocation of mining blocks as direct feed, stockpile or waste. Importantly, this efficiency will be measured in terms of value and not grade, which is an incomplete – and typically biased – proxy for value. The key benefit is that ore control will then be planned and executed on the basis of realised value.We therefore propose a twofold systematic and holistic, value-based geometallurgical process. This process needs to be planned and implemented in an integrated manner, noting that strategic and tactical geometallurgy can be worked on by the same professionals, sharing data, methodologies and potentially models. What differs between the two levels is the required granularity, the business context and (critically) the decision-making time horizons.CITATION:McKay, N, Vann, J, Ware, W, Morley, C, Hodkiewicz, P, 2016. Strategic and Tactical Geometallurgy – a Systematic Process to Add and Sustain Resource Value, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 29–36 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By William M. Bowron

THIRTY years ago, when I stood on the cliff of red fossil iron-ore, on Red mountain, Jefferson county, Ala., I asked what were the geological relations of this remarkable deposit. In reply I was told that it was a limestone colored and saturated by some unknown but wholly external influences, and that at a reasonable distance from the surface the color would disappear. I could find no satisfactory explanation either of the nature of this wonderful external permeating influence, or of the cause of such a ferrous impregnation selecting this one particular bed of limestone, to the exclusion of the higher and lower beds of the same material which are not even stained. I. THE PRESENT THEORY. Referring to this subject, Dana says:' "The clays, clayey sandstones and limestones of the Clinton epoch, through New York and the Appalachians, show that the mud-flats and sand-banks, and hence the shallow seas of the coast region, still continued. . . The beds of argillaceous iron-ore, which spread so widely through New York and some of the other States, south and west, could not have formed in an open sea, for clayey iron-deposits do not form under such circumstances. They are proof of extensive marshes, and, therefore, of land near the sea-level. The fragments of crinoids and shells found in these beds are evidence that they were, in part at least, salt-water marshes, and that the tides sometimes reached them." At first, this explanation seemed satisfactory, but the more I studied the ore the less satisfying the explanation became. 1. In the ore itself I found associated with the small particles of rounded matter (now consisting of iron oxide in which organic structure, if ever present, has become lost, though the

Nov 1, 1905

By Nath S. Parate

With the extension of mining beneath residential and industrial areas, it is becoming increasingly necessary to extract coal and minerals in such a way that subsidence damage due to groundmovement is reduced to a minimum. Understanding clearly of the mechanism of subsidence development is a must in view of the environmental problems and the energy crisis today. This paper gives a simple analysis of various components resulting from subsidence and the influence of other factors on their development. An up-to-date review of the subsidence and strain profiles is presented, with particular references to the coal mining operations. The importance of this topic from mining damage to structures, buildings properties and environment in mining areas is undeniable. Field results are discussed.

Jan 1, 1982

By John F. McCoy

The U.S. Bureau of Mines (USBM) awarded? a contract to Foster-Miller, Inc. to develop guidelines for designing, constructing, stocking, and maintaining rescue chambers in underground mines. This report develops information and recommendations which could be used by a mine operator who desired to install a rescue chamber. Volume I covers the following major areas: atmospheric life support, configuration and construction, chamber location, power and lighting, equipment and supplies, communications, and psychological aspects and training. Volume II contains the following appendices: History of Barricading, Chamber Pressuriztion Considerations, Diffusional Infiltration of Gas, Compressed Air Storage, Location Examples, and Psychological Aspects.

Jan 1, 1983

By Oliver Bowles

The manufacture of lime is one of the oldest industries. Plants are distributed widely and furnish an essential raw material for numerous industries. The use of lime by the building trades, in agriculture, and in hundreds of manufacturing and chemical processes has created demands for a large production and has necessitated exhaustive research on methods of manufacture and uses. The bibliography of lime is an extensive one, but for the most part each publication has dealt with only certain operations. The purpose of this paper is to present a general picture of the industry as a whole. The abundant literature has been abstracted and quoted freely, and the National Lime Association has rendered valuable assistance in furnishing data for certain sections. Publications containing more detailed information on the various branches of the industry are referred to in the footnotes and in the bibliography.

Jan 1, 1936

Mining men and State officials in their efforts to make mining safer are confronted from time to time with various complicated questions. In recent gears these questions have tended to increase with the use of mechanical appliances. Twenty-five years ago electricity had been used but little in mires; today there is practically no other means of transmitting power employed in American mines, except that in metal mines compressed air is used, chiefly for drilling and for operating small portable hoists. In coal mines there has been a great increase in mechanization, which tends to concentrate the work of production in small areas and to increase the local difficulties of ventilation; also, it has intensified locally the hazard from coal dust as well as firedamp in bituminous and subbituminous mines. The answers to the questions that arise are not always obvious, as is shown by the fact that even able, experienced men differ in their opinions of the best, way to overcome a particular mining hazard. The difficulty of .solving the problems is also demonstrated by the varying provisions in mine-safety rules, both in official regulations and in the rules of those mining companies that are endeavoring to do more than follow the letter of the law. Such differences of opinion as to the best way of meeting a difficult situation are often found within the same mining organization, and, similarly, varying opinions are held by different members of the Bureau of Mines staff.

Jan 1, 1937

By R. J. Hundermark, L. R. Nelson

The critical importance of tap-hole design and management to furnace performance and longevity is explored through examining some of the specific matte, metal and slag tapping requirements of non-ferrous copper blister and matte converting and smelting, ferroalloys smelting and ironmaking systems. Process conditions and productivity requirements and their influence on tapping are reviewed for these different pyrometallurgical systems. Some critical aspects of the evolution of tap-hole design to meet the diverging process and tapping duties are examined. Differences and similarities in tapping practices and tap-hole management are reviewed. Finally core aspects of tap-hole equipment and maintenance are identified that are considered important to securing improved tap-hole performance and life, so pivotal to superior furnace smelting performance.

Jan 1, 2014

By Henry Kreisinger

Some of the investigations conducted by the Bureau of Mines have for their object the collecting and disseminating of information regarding methods by which the fuels of the country may be most efficiently used. As the analysis of flue gases tends to develop better methods of firing, which in turn reduces waste of fuel, the Bureau of Mines in this bulletin presents for the benefit of those in charge of boiler plants and all other persons interested detailed information on methods of sampling and analyzing flue gases, and on the utilization of the analyses in promoting boiler-room economy. This bulletin is intended to be a companion to Technical Paper 80,a and is written in plain and nontechnical language, as far as possible, so that it may be readily understood by persons who have not had the advantage of a technical education. Whenever possible, illustrations of apparatus and methods of handling have been used rather than elaborate descriptions.

Jan 1, 1915