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A stronger U.S. economy stimulated the domestic mineral sector in 1994. Metals demand was spurred by robust U.S. motor vehicle sales, while demand for major industrial minerals rose in response to highway and building construction. Domestic mineral and material demand is expected to increase in 1995, particularly if interest rates do not restrain the building industry and international monetary exchange rates remain advantageous to U.S. automobile manufacturers. Additional information on events, trends, and issues in the mineral and material sector is presented below and in the commodity sections that follow. Overall Performance Processed materials of mineral origin produced in the United States during 1994 increased to an estimated value of $360 billion. Domestic output of raw nonfuel minerals in 1994 was estimated at $34 billion, about 6% more than that of 1993. The value of U.S. minerals production has increased in 29 of the last 34 years.

Jan 1, 1995

By Claudia Monreal L., Dafne Herreros

"The Geological Modeling is the undisputed point of split of any type of mining method, the effect that the vision and experience of the geologists is propagated trough the development of the project and is an important part of the final success. The collection of information is taken in stages. In earlier stages uses the greater part of the budget and the strategy to store and manage this data collection, as its performing will define the destiny of the deposit and of the business. With this background the geology and its modeling receive great attention from the industry and care providers being a fertile field in research and innovation. "

Sep 1, 2017

The 1965 Lignite Symposium, the Louth in a series and the third sponsored by the University of North Dakota and the Bureau of Mines, was held at Bismarck, N. Dak., on April 29-30, 1963. These symposia provide a forum for those interested in the technology and utilization of solid fuels, especially lignitic coals. As part of the meeting, a 200-mile field trip was taken including; inspection of (1) the 200-megawatt, pulverized lignit-fired Leland Olds plant of Basin Electric Power Cooperative, under construction near Stanton, N. Dak.; (2) the site of the Glunharold mine of the Truax-Traer Coal Co., Division of Consolidation Coal Co., where a wheel excavator was being assembled; (3) the operating Beulah mine of Knife River Coal Mining Co., subsidiary of Montana-Dakota Utilities Co., near Beulah, N. Dak.; and (4) the 400-megawatt, hydroelectric Garrison Dam powerplant, near Garrison, N. Dak.

Jan 1, 1966

By Compiled by Staff

"INTRODUCTIONThe U.S. Bureau of Mines (USBM) was established in the public interest to conclude inquiries and scientific and technologic investigations on mining and the preparation, treatment, and utilization of mineral substances; to promote health and safety in the mineral industries; to conserve material resources and prevent their waste; to further economic development; to increaseee efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting those industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the U.S. Bureau of Mines to ""disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act.""In accordance with this directive, USBM reports the findings of its research and investigations in its own series of publications and also in articles that: appear in scientific, technical, and trade journals; in "" proceedings of conventions and seminars; in' reference books; and in other non-USBM publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make this kind of list both necessary and valuable.This edition describes reports and articles published during calendar years 1992 and 1993. It supplements the 50-year list of Bureau publications from July 1, 1910, to January 1, 196O 2; and these 5- year lists of publications and articles: from January 1, 1965, to December 31, 1969 4, from January 1, 1970,to December 31, 19745 , from January 1, 1975, to December 31, 1979 6 , from January 1, 1980, to December 31, 1984 7 , and from January 1, 1985, to December 31, 1989 8."

Jan 1, 1994

By R. E. Scheffel

Most supergene copper heap leach operations today employ forced-aeration, irrespective of ore grade. Unfortunately, there is little published quantification of its benefit. There is a natural desire to strive for the ideal chemical kinetics. The reality, however, is that physical mechanisms control the commercial extraction rate. This paper presents the performance of a number of operations, their operating conditions and physical ore characteristics, which contribute to non-ideal solution distribution and variable extraction rate. Regardless whether one uses forced-aeration, commercial experience to date suggests it is prudent to design for longer leach cycle times to ensure the production target is met.

Jan 1, 2006

By J. O. Lewis

In its efforts to reduce waste, and increase efficiencyin oil production, the Bureau of Mines is investigating methods of increasing the recovery from the underground sources of supply, which are the foundation of the petroleum industry and the many allied industries wholly or partly dependent on it. In the face of a demand that is increasing faster than the production and that, in the consensus of opinions of well-informed authorities, is soon likely to outstrip the productive capacity, it is well to consider whether it is not possible to extract more oil from the known sources of supply. It is universally acknowledged that by the usual production methods much oil is left underground, the general opinion being that at least 50 per cent of the oil in a field remains unrecovered when the field is abandoned as exhausted. From the writer's own investigations he believes the average recovery is even less, and if any considerable portion of this oil being left underground could he made available it would have a tremendously favorable influence on the petroleum industry and all the industries dependent on it. In this publication are considered the principles involved in increasing recovery and methods of extracting more oil from the oilbearing formations than by the usual ways of producing. These methods are: The use of gas or vacuum pumps, forcing compressed air or gas through the oil-bearing formations, displacing the oil by water, and better utilization of the natural pressures in the oilhearing formations. Especial attention is being given to a processcommonly known as the Smith-Dunn-for forcing compressed air through oil-bearing formations because it is believed to hold most promise for the future.

Jan 1, 1917

By Jack L. Henry

The ternary system A14C3-AIN-Al203 has been examined to determine compositions which may display desirable high-temperature refractory properties. Powder methods were employed in the synthesis of all test compositions. Forming and sintering behavior was examined and hot-pressing parameters were measured. Several properties were studied for each composition of interest in the system. The properties included hydrolysis rate in moist air, elevated temperature oxidation rate, density, softening point, tensile strength, and rupture strength. In most cases equilibrium was not achieved, and the data are representative of a nonequilibrium system. Approximately 16 separate phases have been observed in the system. Forming behavior and selected properties of five compositions of interest were compared with those of aluminum oxide and aluminum nitride. None of the compositions compared favorably. Oxidation and vaporization appear to be serious drawbacks to the use of these compositions at elevated temperatures.

Jan 1, 1969

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 Yi Luo

Bolting the mine roof is one of the noisiest underground mining operations. The main contribution to the noise is the drilling of the roof bolt holes, especially drilling in hard rock. Previous research shows that the specific energy consumed in drilling bolt holes is inversely proportional to the bite depth (i.e., penetration per drill revolution). Less specific energy at a reasonably high bite depth means less energy is wasted in the drilling process for producing heat, bit wear and noise. Therefore, proper control of the drilling operation to achieve a reasonably higher bite depth can reduce drilling noise from its sources as a proactive noise control approach. In order to explore the feasibility and develop the proactive technology for reducing drilling noise, drilling tests have been conducted in laboratory settings. The preliminary results show that significant reduction in noise dose can be achieved by drilling in medium hard rock with uniaxial compressive strength of about 276 bars (4,000 psi) and at a reasonably high bite depth of about 4.6 mm/rev (0.18 in./rev). This paper presents the findings from laboratory experimental studies.

By D. Komljenovic, J. Paraszczak

"This paper presents the use of queuing theory in truck fleet sizing in open pit mining operations. In the first part, a methodology is developed by which an optimal ratio between the size of shovels and trucks may be determined. The second part gives the fundamentals of the queuing theory and its application in analyzing shovel and trucks. The stochastic character of involved times (loading, truck cycle, etc.) is taken into consideration. Using the above theory, the optimal truck fleet size in actual conditions may be estimated. Minimal operating cost of the working system (shovelstrucks) represents the basic requirement of the analyzed process. The methodology was validated on Caterpillar front-shovel – truck combinations. IntroductionLes camions représentent probablement les équipements les plus utilisés pour le transport dans les mines. Le coût de transport peut parfois atteindre 50 % du coût d’exploitation et 25 % du coût total (Collins, 1996; Kennedy, 1990). Il est critique pour une opération minière de le minimiser. C’est un sujet qui a été traité relativement souvent dans la littérature spécialisée. Les premières applications informatiques dans l’industrie minière ont été développées pour la détermination du temps de cycle des camions.Au fil des ans, la capacité des camions a augmenté et, aujourd’hui, les plus gros manufacturiers de camions (Caterpillar, Orenstein & Koppel, Euclid, Terex, Unit Rig, Komatsu, Liebherr, Belaz) fabriquent des camions ayant une capacité de 200 t et plus dont quelques-uns d’une capacité supérieure à 320 t. Pour les plus gros camions, le coût d’opération peut même dépasser 240 $US/heure dans des conditions modérées (Caterpillar, 1999). Les mines modernes de grande taille peuvent posséder plusieurs dizaines de camions dans leur flotte."

Jan 1, 2004

By Ronald M. Hays

The Duluth Gabbro Complex in Northeastern Minnesota possibly contains a significant domestic copper resource and the nation's largest nickel resource. Exploration has discovered large low-grade copper-nickel (Cu-Ni) deposits between Hoyt Lakes and the Boundary Waters Canoe Area (BWCA). The mining and processing of Cu-Ni will have environmental, economic, and social impacts. The purpose of this study is to relate major environmental, economic, and social considerations to various aspects of Cu-Ni extraction. An open pit and two underground (block caving and open stoping with backfilling) models were developed to generate information on the impact of Cu-Ni extraction. Important considerations having environmental, economic, and social impacts (luring various aspects of Cu-Ni extraction are identified and defined. These aspects are exploration, development, mining, beneficiating, smelting, transportation, and termination of operations. Considerations are grouped into the general categories of site, industrial, energy, climatic, resource, water, air emission, waste disposal, employee, tax and royalty, transportation, and community considerations. Cu-Ni extraction in Northeastern Minnesota presents major environmental, economic, and social risks. Decisions are required on trade-offs between adverse and beneficial impacts. The approach used in this study assists in assessing environmental, economic, and social impacts. It will aid in the examination of potential and projected short-term and long-term advantages and disadvantages and will aid in the development of Minnesota's Cu-Ni resource for the maximum benefit to society.

Jan 1, 1974

By Robert McClure, Frederic Leclercq, Ricardo Chavez

With significant vibration control and fragmentation challenges facing them, the CBS quarry (department of the Nord) successfully integrated a technical partner and mine to mill optimisation to deal with a difficult environment. For the last three years, CBS has been conducting a global production monitoring program similar to the mine to mill concept used in the mining industry. This concept consists of optimising the drilling and blasting while monitoring the effects on the downstream chain (vibration control, loading, hauling, crushing, plant output). Blast optimization is ensured by systematic control of the blast geometry (volumes, patterns, bench and face anomalies, drill deviation) and by the use of constant specific energy blasting. Constant specific energy optimises the work of the explosive in a blasting operation and, when combined with a high accuracy programmable electronic blasting system, reduces the impact of blasting on the environment and enhances blast performance. These techniques ensure consistent blasting results and hence improved site productivity. The improvements achieved have been identified thanks to an effective system designed to monitor the key production parameters.

Jan 1, 2007

By W. R. K. Wu

This bulletin traces the development of high-pressure, coal and tar hydrogenation technology, based on an intensive review of the pertinent literature. The bulletin was written as a part of the Bureau of Mines research program on synthetic liquid fuels. It covers the history and economics of the process; the chemical aspect of hydrogenation of coal, tar, and middle oil; the engineering aspect of converting coal and tar to liquid fuels, principally gasoline; and the equipment for the process. The literature covered includes documents of the United States and British Governments, journals, and other publications. Bureau results in the hydrogenation field are also incorporated.

Jan 1, 1968

By C. Haycocks

The problems caused by interaction in multi-horizon mining are world wide and are not limited to the coal industry. These problems will continue to increase as mining of new seams multiplies and replaces production from mined out horizons. Interaction problems are particularly evident in the Appalachian coal fields which contain many mineable, contiguously placed coal seams. Selection of the mining sequence of these seams, historically and currently, is based primarily on considerations of seam ownership, availability, and economics. Experience has shown, however, that mining any seam can seriously affect subsequent operations in coal seams both above and below the one being mined. This interaction effect is often detrimental to the recovery cost and safety of mining the subsequent seams. Designing to avoid or minimize interaction effects represents a major challenge to the modern coal mining industry and therefore is the focus of this research. In an effort to evaluate past interaction effects and provide guidelines for future mine design, interactive ground control problems were categorized into four areas. These are pillar load transfer, massive interseam shearing, subsidence and pressure arching effects. To facilitate research, each of these areas was studied separately although in reality these subdivisions are arbitrary and have considerable overlap.

Jan 1, 1983

By Charles L. Parsons

Early in 1912, from information received by the Bureau of Mines, it became evident that quantities of valuable radium-bearing ore from Colorado were being exported for manufacture in foreign countries and that at least part of the manufactured product was being returned to this country and sold at a price entirely incommensurate with that received by the miner and the prospector. Consequently, in line with its efforts to increase efficiency in the mining and treatment of mineral resources, the Bureau of Mines undertook an investigation of conditions. Results of this preliminary investigation were published, in the summer of 1913, as Bulletin 70,a which gave an outline of the radium deposits of the West, the conditions of mining, the wastes involved, and the status of the production of radium from its ores. At about this time newspapers and medical journals were publishing statements regarding the value of radium in cancer therapy. These reports, although many of them were exaggerated, brought out clearly the remarkable virtue of the gamma rays for the treatment of cancer and other malignant growths. In view of the fact that the largest known supplies of radium ore in the world are in the States of Colorado and Utah and on the public lands of the United States, it was deemed highly important for the Bureau of Mines to study the production of radium in detail. Such study, it was hoped, would enable the prospector and miner to obtain a fairer price for the ores and would furnish information necessary in case Congress appropriated funds to develop methods for extracting radium from ore on the public lands under Government supervision, to be supplied at cost to the hospitals of the Army, Navy, and Public Health Service.

Jan 1, 1915

By A. Thoraval, K. B. Slimane, O. Ozanam

The REP experiment is part of the research programme conducted by Andra to investigate the possibility of reversible radwaste disposal in a Jurassic (Callovo-Oxfordian) argillite formation at the Meuse/Haute-Marne underground laboratory site in northeastern France. The experiment focuses on the hydromechanical response of the formation to sinking the laboratory access shaft. Modelling of boreholes and shaft sinking operations has helped to optimise measurement point locations based on initial stress tensor anisotropy, while minimising interaction between instrument boreholes. Analyses were made of model sensitivity to intrinsic rock characteristics, hydromechanical coupling properties and sensor installation procedures. L’expérimentation REP fait partie du programme de recherche pluridisciplinaire engagé par l’Andra pour étudier la possibilité d’un stockage réversible des déchets radioactifs dans la formation Callovo-Oxfordienne des argilites du site de Meuse/Haute-Marne (Commune de Bure - France). Cette expérimentation permettra d’étudier la REponse hydromécanique de la formation aux sollicitations engendrées par le fonçage du Puits d’accès du laboratoire souterrain de recherche. Afin d’optimiser le positionnement des points de mesures, compte tenu de l’anisotropie du tenseur des contraintes initiales, et de minimiser les interactions entre les forages d’instrumentation, des modélisations des forages et du creusement du puits ont été conduites. Des analyses de sensibilité aux caractéristiques intrinsèques de la roche, aux propriétés de couplage HM et aux protocoles d’installation des capteurs ont été faites. Die REP-Untersuchung ist Teil des multidisziplinären Forschungsprogramms, das die ANDRA im Callovo-Oxfordian-Tonstein in situ am Standort Meuse/Haute Marne (Gemeinde Bure – Frankreich) im Hinblick auf eine Eignung zur reversiblen Lagerung radioaktiver Abfälle durchführt. Dabei soll das hydro-mechanische Verhalten der Formation auf die Beanspruchungen, die durch das Abteufen des Zugangsschachts zum Untertage-Forschungslabor erzeugt werden, untersucht werden. Zur optimalen Positionierung der Messpunkte unter Berücksichtigung der Anisotropie des Tensors der Ausgangsspannungen und zur Minimierung der gegenseitigen Beeinflussung der Instrumentierbohrungen wurden ein Schachtabteuf- und Bohrmodelle entwickelt. Zur Untersuchung der inhärenten Eigenschaften des Gesteins, des gekoppelten HM-Verhaltens und der Installationsprotokolle der Messsonden wurden Sensibilitätsanalysen durchgeführt.

Jan 1, 2003

By Greg Barnes

Agenda ? The Mining Stock Life Cycle ? Current Environment ? Valuation ? Golds ? Valuation ? Base Metals ? Case Study ? Quebrada Blanca Hypogene Commodity Investment Cycle ? Macro-Economic Indicators ? LME Inventories ? watch the trend; rising inventories ? bad for prices, declining inventories good for prices ? OECD Leading Indicators ? PMIs ? Purchasing Manager Indices ? Industrial Production ? more important for metals consumption than GDP ? Housing Starts ? US, Europe ? Auto Sales ? All things China ? metal imports/exports; SHFE inventories; SRB stockpiling ? Seasonality ? it does play a role ? What is Chris Dutton (TDSI Quantitative Analyst) saying?

May 1, 2010

By L Schürmann, R Kendall

Social licence to operate is becoming part of a mining company’s DNA in the same way as health and safety. Consequently, mining companies are receiving increasing pressure from their shareholders to ensure that they add enduring value to the local communities in which they operate. Apart from the shareholders, a company has responsibility to suppliers, customers, employees, the government and the community, which means under the social responsibility model they must be accountable to the other stakeholders. External and internal challenges in mining are increasing the difficulty and complexity of mines to operate. The external mining environment has a big impact on mining operations and is driving matters such as the focus on safety, responsible mining and resource management, sustainability issues, profitability and productivity. Considering this, it is expected that the widespread implementation of Environmental, Social and Governance (ESG) related practices across the mining industry in the next ten years will increase, not just for the big players but for juniors as well. Companies, investors, governments and insurers who fail to act on ESG matters are to likely face greater risks. Demonstrating leadership in ESG will ultimately become a differentiating factor and market participants have much to gain from embracing ESG stewardship as part of their competitive advantage. Stock Exchanges have an important role to play in advancing sustainability in the capital markets. It is for this reason that the Sustainable Stock Exchanges (SSE) initiative was founded to serve as a global platform for exploring how exchanges can enhance performance on ESG issues and encourage sustainable investment. The SSE initiative provides an effective platform for dialogue between the United Nations, stock exchanges, investors, companies and regulators in the mining industry. The paper will explain why ESG reporting is crucial for the survival of a mining company and how the lack of transparency could be detrimental to its public image and shareholder relations. The paper will also identify bodies that regulate ESG reporting, as well as the available tools that provide guidelines on reporting ESG matters. Key ESG reporting parameters (at a global scale) will also be highlighted.

Jun 22, 2022

By B Hayter, M Carr, K Williams, C Wheeler, W Chen

Current trends into mining iron ore have seen an increase in the exploitation of problematic orebodies that would typically be disregarded. These bulk materials cause problems within all facets of the material handling stream, from remains left in train wagons to transfer chute blockages, which can cause costly downtime to mining operations (Roberts, 1998). These problematic bulk materials are referred to as wet and sticky material (WSM) due to the adhesive and cohesive nature they possess. Their characteristics can be computationally expensive to model. With the development of discrete element modelling (DEM), in conjunction with advancement in computational power over the past decade, it is now more feasible to model WSMs into the DEM technique.This research will couple two different contact models that can represent the characteristics of a WSM. These models include the Simplified Johnson-Kendall-Roberts (SJKR) and the Easo liquid bridging contact models. The SJKR contact model is an expanded form of the classic Hertz model. This model includes the tensile forces that are in the contact zone between two bodies when they are separated, which the Hertz model failed to capture (Johnson, Kendall and Roberts, 1971). The Easo liquid bridging contact model accounts for the capillary effects and surface tension that will form between two bodies, such as that of a WSM (Soulié et al, 2006). Both of these models were coupled to give the best representation of a WSM, which was simulated using MoleculeX™ (Chen and Williams, 2017) as the software platform.Additionally, this research also investigated the adhesion of problematic iron ore samples onto impact plates under dynamic conditions. An experimental set-up consisting of an apron feeder and inclined impact plate was utilised, to gain an understanding of the way the material builds-up and the possible modes of failure that could be experienced. This was undertaken for different wall liner materials, wall liner angles and moisture contents of the iron ore samples. From this, a series of DEM calibration simulations were conducted on the experimental set-up and particle size distributions (PSD) of the iron ore samples. This enabled forming of a database of parameters, which can be scaled for on-site applications in relation to geometry of the plant and PSDs that would represent run-of-mine ores.CITATION:Carr, M, Williams, K, Chen, W, Hayter, B, Roberts, A and Wheeler, C, 2017. The dynamic adhesion of wet and sticky iron ores onto impact plates, in Proceedings Iron Ore 2017, pp 511–518 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By J. K. Szymanski

"RÉSUMÉPour maintenir de bonnes performances technique et économique dans l’exploitation par chambres vides (open stope) il est primordial d’assurer un contrôle efficace des limites réelles des chantiers d’abattage. C’est pour cette raison que, de plus en plus souvent, les opérateurs miniers utilisent un dispositif de laser (Cavity Monitoring System: CMS) qui permet de mesurer les dimensions réelles de chantiers en vue de calculer principalement la dilution et les pertes du minerai ainsi que d’autres paramètres. Malheureusement, il n’existe présentement aucune méthodologie commune, qui permettrait d’interpréter ces résultats selon les mêmes critères pour faciliter d’évaluations juste et précise de la réalisation par rapport à la planification en vue d’en apporter de corrections, dans les différentes opérations minières, si nécessaire. Dans la première partie du présent article on discute les principales séquences d’exploitation utilisées dans l’extraction par chambres vides. Par la suite, à l’aide des sections transversales et longitudinales on illustre toutes les phases des travaux miniers. Ceci en vue de permettre au lecteur de comprendre mieux c’est qui peut se passer effectivement dans les chantiers d’abattage. Par après on donne les définitions générales de principaux facteurs de performance technique. Finalement, l’exemple numérique, élaboré à partir des résultats de l’arpentage au laser effectué par la mine Bousquet 2 dans un chantier d’abattage, donne les détails concernant les définitions ainsi que les valeurs de nombreux facteurs de performance technique, qui pourraient être utilisés, par après, par les opérateurs miniers dans le suivi de leurs exploitations souterraines."

Jan 1, 1997