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By J R. Goff, R Carver, D S. Sheppard

The REGCHEM (Regional Exploration Geochemistry) stream sediment geochemistry database of open file mining company data, managed by GNS Science, was recently made accessible via the internet (http://maps.gns.cri.nz/website/minmap/). REGCHEM provides coverage of selected elements in mineral rich areas of New Zealand. Analysis of REGCHEM data highlights problems with inconsistencies between different surveys in terms of sampling methods, number and types of elements analysed, analytical techniques and detection limits. New, consistent multi-element geochemical surveys with national coverage are required. To test sampling, analytical and data treatment techniques for the new surveys, a pilot stream sediment geochemical survey was carried out in the Thames area, Hauraki Goldfield. Seventy samples were collected in an area of 220 km2 representing about one sample every 3 km2. The samples were analysed for 50 elements, mostly by XRF.   Regional patterns are apparent in the concentrations of some elements. Several elements, such as As, Cd, Cu, K, Pb, Sb, Se, and Zn exhibit anomalous concentrations mainly in the western part of the study area, related to Au-Ag-Zn-Pb-Cu epithermal quartz veins and porphyry Cu occurrences in hydrothermally altered andesitic terrane.   Mercury is anomalous in southern samples, reflecting cinnabar occurrences in the Kauaeranga valley (eg Mangakirikiri), and the occurrence of cinnabar as a late stage mineral in some of the Thames epithermal veins. Ba and U are anomalous in the eastern samples, and these anomalies are probably related to the presence of rhyolitic rocks in the eastern part of the project area.

Jan 1, 2006

Trans No. Place Date Vol. 1. Wilkes-Barre, Pa' May, '71 1 2. Bethlehem, Pa Aug., '71 1 3. Troy, N. Y Nov., '71.. 1 4. Philadelphia, Pa Feb., '72.. 1 5. New York, N. Y.' May, '72.. 1 8. Pittsburgh, Pa Oct., '72.. 1 7. Boston, Maas Feb., '73.. 1 8. Philadelphia, Pa." May, '73.. 2 9. Easton, Pa Oct., '73.. 2 10. New York, N. Y Feb.. '74.. 2 11. St. Louis, Mo.* May, '74.. 3 12. Hazleton, Pa Oct., '74.. 3 13. New Haven, Conn Feb., '75.. 3 14. Dover, N. J. ? May, '75.. 4 15. Cleveland, 0 Oct., '75.. 4 16. Washington, D. C Feb., '76.. 4 17. Philadelphia, Pa.} June, '76.. 5 18. Philadelphia, Pa Oct., '76.. 5 19. New York, N. Y Feb., '77.. 5 20. Wilkes-Barre, Pa. ? May, '77.. 8 21. Amenia, N. Y Oct., '77, . 6 22. Philadelphia, Pa Feb., '78:. 6 23. Chattanooga, Tenn.*...May, '78'.. 7 24. Lake George, N. Y Oct., '78.. 7 25. Baltimore, Md.* Feb., '79.. 7 26. Pittsburgh, Pa Mayo '79.. 8 27. Montreal, Canada Sept., '79., 8 28, New York, N. Y.? Feb., 'SO.. 8 29. Lake Superior, Mich. ..Aug., '80.. 9 30. Philadelphia, Pa.' Feb., '81.. 9 31. Staunton, Va May, '81..10 32. Harrisburg, Pa Oct., '81..10 33. Washington, D. C.? ....Feb., '82..10 34. Denver, Colo Aug., '82..11

Jan 1, 1928

By C. Birch

"A mineral resource royalty is payment to the holder of mineral rights for the utilization of the mineral resource. In South Africa, this payment is made to the State as holder of the mineral rights (The Mineral and Petroleum Resources Royalty Act of 2008). The principle purpose of this research paper is to identify if the State is benefitting from the mineral resource royalty by considering its impact on seven individual Witwatersrand gold mines.For this study, a simple financial optimiser model was created in Microsoft Excel that links the ore flow, block listing and the cash flow (excluding or including the cost of the mineral resource royalty). Mixed integer linear programing (the Excel Solver function) is utilised to optimise either profit or NPV (at 9% and 12%) by adjusting the cut-off grade.The impact on each of the seven mines mine was different but overall R7.9 billion is estimated to be paid in mineral resource royalty over their expected remaining lives. Due to the cost of the mineral resource royalty and increasing the cut-off grades, the total revenue decreases by R10 billion. A significant portion of this lost revenue would have been paid to the State in the forms of other taxation including company income tax which decreases by R2.8 billion. It is recommended that an industry wide investigation be conducted to determine if the resource royalty is adding to the State’s revenue, or destroying value including premature job losses. IntroductionTaxation of mining companies has become a very topical subject in the context of the postapartheid South African economy. There have been increasing calls for equitable re-distribution of mineral asset wealth for the benefit of all South African citizens and not just to an elite few. As part of the Mineral and Petroleum Resources Development Act (MRDPA) of 2002, the Mineral and Petroleum Resources Royalty Act of 2008 was introduced and came into effect in 2010 (South African Revenue Services, 2008). A mineral royalty is payment to the holder of mineral rights for the utilization of the mineral resource. In the case where the holder of the mineral right is the State, then this payment is made to the State (Cawood, 1999). Studies on the potential impact of the mineral resource royalty on the minerals industry have been conducted during the formulation of the Act and subesquently. These include Cawood and Macfarlane (2003), who suggested a cap of no more than 3% (Cawood and Macfarlane, 2003), as well as Cawood (2011), who predicted rising cut-off grades and thus reducing mineral reserves. In 2013, Grobler completed a Masters in the Faculty of Economic and Management Sciences at the University of Pretoria and concluded that the impact of the mineral resource royalty on the economy is positive. She stated that the royalty has caused operating expenses to increase, but this does not appear to be significant. Furthermore, she stated that the royalty has not affected the way the mining industry operates (Grobler, 2014)."

Jan 1, 2016

By G. A. Vissac

In this paper we intend to deal particularly with the economic side of coal washing as it applies to our mines. We will then discuss why the dry-cleaning process has been selected, and give a brief description of our plant, dwelling only on its specific features and referring the reader to the numerous papers published on the subject for any details on the principles and machinery used in dry cleaning. ECONOMIC DISCUSSION The washery introduces an extra cost for depreciation, operation, and loss in treatment. A certain proportion of the coal, now being sold, and which the miners have been paid for. will have to be wasted. As a whole, the total increase in cost would be approximately 60 cents per ton. On the possibility of recovering this amount depends the success of the washery. There are two advantages to be expected from the washery, the first, which occurs at the mine and which will be certain; the second, more difficult to estimate, because it depends upon convincing our customers that they should pay more for a better product.

Jan 1, 1924

By A. V. Z. Brink

Rock engineering risk is defined in this paper as a function of the potential ground motion; the vulnerability of the workplace; exposure of people; and a general term – quality of information. The paper describes the development of prototype software that is a combination between an expert system approach for determining overall risk assessment, a risk control recommendation and a basic GIS (Graphic Information System) approach for graphically overlying input parameters and the output risk. The expert system uses a Bayesian probabilistic approach to combine various workplace-related information, a quantified seismological environment and the exposure of underground staff to provide an overall RE risk rating. The risk assessment is dynamic in that it is recalculated each time that any of the input parameters change, for example each time a seismic event is recorded in the area of interest. The code was tested on a data set from Savuka Gold. As risk assessment is not an absolute prediction of a specific outcome, it is therefore not possible to relate to individual case studies and the reliability of this method would only be determined after an extensive period of use with appropiate back-analysis. Le risque dans le génie minier est défini dans cette étude comme une fonction du mouvement potentiel de terrain ; la vulnérabilité du lieu de travail ; l’exposition des personnes ; et un terme général – la qualité de l’information. L’étude présente décrit le développement d’un logiciel prototype qui est une combinaison entre une démarche de système expert pour déterminer une évaluation générale du risque, une recommandation pour le contrôle du risque, et une démarche de SIG (Système d’Information Géographique) pour superposer graphiquement les paramètres d’entrée et le risque de sortie. Le système expert utilise une méthode de probabilité bayésienne pour combiner des informations variées sur le lieu de travail, des données quantifiées sur l’environnement sismique, et l’exposition du personnel travaillant sous terre, pour finalement produire un classement général de risque minier (RE). L’évaluation du risque est dynamique en ce sens qu’elle est recalculée à chaque fois qu’un des paramètres d’entrée change, par exemple à chaque fois qu’un évènement sismique est enregistré dans la région. Le code fut testé sur un ensemble de données obtenues de Savuka Gold. Comme l’évaluation du risque ne constitue pas une prédiction absolue d’un résultat spécifique, elle est par conséquent difficile à rattacher à des cas individuels et la validité de cette méthode ne pourrait être déterminée qu’après une longue période d’utilisation avec analyse rétrospective appropriée. Das Gesteinstechnikrisiko wird in dieser Arbeit als Funktion einer möglichen Bodenbewegung definiert; die Anfaälligkeit des Arbeitsplatzes; das Ausgesetztsein der Belegschaft; und ein genreller Begriff - Qualität der Informationen. Das Papier beschreibt die Entwicklung einer Prototyp-Software, die eine Kombination zwischen einem Expertensystemzugang für die Bestimmung der gesamten Risikobeurteilung ist, eine Empfehlung zur Risikokontrolle und eines fundamentalen GIS (graphisches Informationssystem) Zuganges für graphisch darüberliegende Eingangsparameter und das Outputrisiko. Das Expertensystem verwendet eine bayesische Wahrscheinlichkeitsannäherung, um verschiedene mit dem Arbeitsplatz in Verbindung stehende Informationen, ein quantitativ bestimmtes seismologisches Umfeld und das Ausgesetztsein des Untertag-Personals zu kombinieren, um eine gesamte RE-Risikobewertung zur Verfügung zu stellen. Die Risikobeurteilung ist insoferne dynamisch,daß sie stets nachkalkuliert wird wenn sich irgendeiner der Eingangsparameter ändert, z.B. jedesmal wenn ein seismischer Fall im Interessensbereich aufgezeichnet wird. Der Code wurde auf einem Datenbestand von Savuka Gold geprüft. Da die Risikobeurteilung nicht eine absolute Vorhersage eines spezifischen Resultates ist, es ist folglich nicht möglich, sich auf einzelne Fallstudien zu beziehen und die Zuverlässigkeit dieser Methode könnte nur nach einer umfangreichen Benutzungsdauer mit geeigneter Postanalyse bestimmt werden.

Jan 1, 2003

By K. Osburn

South Deep Gold Mine, owned by Gold Fields Ltd., is situated near Westonaria in the Gauteng Province of South Africa and mines the conglomerate bands of the Upper Elsburg reefs (Mondeor Conglomerate Formation) of the Witwatersrand Supergroup and the Ventersdorp Contact Reef (VCR) of the Ventersdorp Supergroup. The stoping and underground developments are mechanized. The Upper Elsburg reefs are mined by a variety of mining methods, including mechanized drift and fill, modified drift and bench, longhole stoping, and low-profile mining. Optimal mine design and scheduling for deep-level mechanized mining are complex, and success is highly dependent on detailed, robust, and accurate geological and geostatistical models. Geological structures significantly influence the sedimentological characteristics, distribution, and preservation of the Upper Elsburg reefs and VCR. Accordingly, particular emphasis is placed on the generation of a mine-scale structural model that accommodates the relationships between the older north-trending fault systems (West Rand and Panvlakte faults) and younger east-trending dextral wrench faults. Results from underground mapping, borehole intersections, and highresolution three-dimensional seismic data have been integrated to produce coherent three-dimensional geological models. The Upper Elsburg reefs suboutcrop against the VCR and comprise an easterly diverging clastic wedge, thickening from the suboutcrop position, to approximately 130 m at the mine?s eastern boundary. The Upper Elsburg reefs are characterized by conglomerate and quartzite bands forming multiple, stacked, upward-fining unconformity-bounded couplets. Palaeocurrent directions are dominantly from west-northwest to east-southeast, indicating that the more proximal deposits are preserved close to the suboutcrop, with distal facies to the east. Sedimentological modelling is applied to individual stratigraphic units and caters for facies definition. This is achieved through channel width (CW) kriging and fitting of type sections to borehole and mapping data. Homogenous geological geozones for each stratigraphic unit are thus defined within individual structural blocks on the basis of those sedimentological parameters that have been found to have a positive spatial correlation to gold concentration. These geozones then serve as constraints to the evaluation of the orebody. This contribution presents a summary of the modelling processes that are currently applied in the development of high-confidence, timeously produced geological models that are essential input for mineral resource estimation and mechanized mine planning and scheduling.

Jan 1, 2014

There remains considerable controversy in the industry regarding precision type detonators and where the end user can benefit from their use. In spite of the fact that electronic detonators and other prototypes were tested over one decade ago, explosive suppliers have hedged on full scale production for many reasons. Although some of the reasons were based on solid economics, others were strongly influenced by shear internal resistance within the corporate objectives, ultimate fear of market rejection, indecision as to what degree of precision was required and limited data on defining the real benefits to the end user.

Jan 1, 1992

By Frederick M. Fowkes

Dusts can be filtered out of air streams onto polymer surfaces by electrostatic trapping resulting from the spontaneous transfer of electrons upon contact between dust particles and the polymer surfaces. Such spontaneous contact electrification has been studied quantitatively in this contract with the aid of modern semiconductor charge-sensors with the aim of determining what basic principles govern the sign and magnitude of contact electrification. Information obtained by capacitance-voltage measurements of thin polymer films on silicon showed that charges as large as 4 x 1012 electrons per cm2 develop spontaneously, and that such a charge gives adhesional forces of 165 pounds per square inch (11 atmospheres). Direct measurement of dust polymer contact electrification, using silicon surface channel conductance sensors, also showed spontaneous charges of more than 1012 electrons per cm2. Some polymers can either donate or accept electrons. These included chlorinated polyethylene, chlorinated polypropylene, polyethylmethacrylate, and a copolymer of maleic anhydride with n-octadecylvinylether. Other polymers never accepted electrons but could donate electrons; these included polystyrene, pulychlorostyrune, polyvinylchloride, polyvinylacetate, a polycarbonate (Lexan), and cellulose tributyrate. Contact electrification studies were made with dusts (coal dust, a channel black, or a silica powder) contacting thin films of various polymers solvent-cast onto the semiconductor charge-sensor. Sometimes charging was instantaneous and sometimes slower, but in all but one case (coal dust on a copolymer of maleic anhydride with n-octadecylvinyl ether) the charge trunsfer was a donation of electrons by the polymer to the dust. Some

Jan 1, 1973

By K Kongolo, M K. Kalenga

It is well known that the electrochemical precipitation of metals from aqueous solutions is conducted by the electrochemical standard potential scale. This scale indicates the order of nobility of different metals. Consequently, the standard potential scale shows the nocivity of metals when they are present as impurities in aqueous solutions containing metals. In the hydrometallurgy of cobalt, nickel and zinc are co-deposited during cobalt electrodeposition. Nickel has almost the same chemical, physical and electrochemical properties as cobalt. Furthermore, the electrochemical potential of nickel is relatively higher than that of cobalt. For this reason nickel is preferentially reduced at the cathode in the presence of cobalt. The presence of small amounts of zinc in solution leads to contamination of cobalt electro won. In spite of its lower electrochemical potential in comparison to cobalt, zinc is reduced on the cathode because of its higher hydrogen-overvoltage. But, in the hydrometallurgy of zinc, small amounts of cobalt present into solution will contaminates the zinc reduced at the cathode. This is easily explained by the fact that cobalt is more electropositive than zinc. The co-deposition mechanism of sulphur at the cathode is not yet well understood. Great attention has to be paid to the mechanism of co-deposition of sulphur during cobalt electrolysis..This work aimed to investigate the influence of some parameters on the co-deposition of nickel, zinc and sulphur during cobalt electrowinning. The following parameters have been investigated : Co2+ concentration in the electrolyte, current density and ammonium sulphate (NH4)2SO4 additions. It has been established that important nickel, zinc and sulphur co-deposition takes place at relatively low Co2+ concentration in solution. The behaviour of these elements with regard to the cathodic phenomena has been established.

Jan 1, 2005

The development of research activities at Risdon and the implementing of a policy of instrumentation in plant processes have, in recent years, entailed a considerable increase in research staff and created an urgent need for more space and modern laboratory facilities. The existing laboratories have been in use for 25 years and are now inadequate. New buildings have been authorized.The new buildings will comprise, firstly, a laboratory building of three floors giving a totai .floor space of approximately 11,000 sq.ft., and a pilot plant building as an annexe to the laboratory building, of approximately 4,900 sq.ft. The laboratory building will accommodate from 20 to 22 research workers, and additional plant operatives will be used for the control of processes in the pilot plant building. The new buildings are designed to provide facilities for three principal functions; the investigation and improvementof existing processes, the development of new processes up to the pilot plant stage, and the control and maintenance of instruments.LOCALITY AND ORIENTATION OF BUILDINGSThe site of the buildings is elevated ground on the eastern side of the main plant, near the main entrance and general office building. There will be no obstruction to sunshine at any time of the day, and the laboratory building will command views of wide radius from wooded hills across the River Derwentto the open sea on the south-eastern quarter.The buildings are located to provide space for future extensions. The main laboratory building faces approx...

Jan 1, 1949

By Judy B. Jones, Bradley A. Crenshaw, Theodore DePooter

This paper reviews groundwater issues leading to a secondary grouting program at the Chattahoochee Tunnel that was implemented subsequent to the contact grouting program. The secondary grouting program was developed based on infiltration data, geology, and testing programs. This paper includes a brief description of the geological features encountered, as well as describing the grouting program. The success of this grouting operation has been quantified by several methods, and is presented to help others project the costs and benefits of this type of program. Review of initial results and refinements of techniques are also discussed.

Jan 1, 2005

By Misra V. N

Upgrading of a Koolanooka magnetite iron ore sample provided by Kingstream Steel Ltd was investigated using low intensity magnetic separation (LIMS) and reverse flotation. The ore contained 38.6 per cent iron, 37.8 per cent silica, 6.5 per cent magnesia and 0.54 per cent alumina, with the main minerals in the ore being amphibole (42 per cent), magnetite (39 per cent) and quartz (14 per cent). The concentrate obtained after low intensity magnetic separation contained 66.6 per cent iron and 6.34 per cent silica with an iron recovery of 72 per cent. This concentrate was further treated by reverse flotation to increase the iron content and reduce the silica content to meet the requirements for direct reduction iron (DRI) feed grade.

Jan 1, 1999

By H. M. Chikashi

Keywords: Pyrometallurgy, furnace, bath agitation, regression analysis, entrainment This paper presents the results of linear regression analysis of the influence that each component of slag has on the losses of copper in slag-cleaning-furnace slag. Data used for the analysis are actual plant data collected over the past two years of operation. Facts obtained from the study will be helpful for smelter management to control these components in the flash smelting furnace feed and slag, to levels which will enable better control of copper in slag, and smoother operation of the KCM slag-cleaning furnace.

Jan 1, 2011

TO THE. BOARD OF DIRECTORS AND MEMBERS OF THE AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS GENTLEMEN Submitted herewith are the report of the Treasurer for the year 1945 and reports for the same year of the following committees: Membership, Admissions, Papers and Publications, Mining and Metallury (Magazine), and Library. In this review of the year by the Secretary reference frequently will be made to the "Paul" Committee and to the "hotter" Committee. The first is the special committee on Divisional Relationships and the second the special Committee on Ways and Means. These two important committees, appointed by President Harvey S. Mudd under authorization of the Board of Directors on March 21, 1945, were composed as follows:

Jan 1, 1946

By R. K. Dunham, D. J. Reddish, X. L. Yao

Paper presented at the conference: Risk assessment in the extractive industries, held in Exeter, UK, 23-24 March 1994, and first published London: IMM, 1994, preprint volume, 10pp., 10 refs. The integrated approach combines a powerful ground movement prediction program with a knowledge-based expert system. ESDAS (Expert Structural Damage Assessment System) was developed to evaluate mining subsidence damage in the form of risk and in terms of the three vital contributing components (mining factors, site factors and structural factors). Using a certainty factor risk assessment technique, the system can be used to predict the likely damage to a particular structure subjected to mining subsidence. A previously developed powerful ground movement prediction program, SWIFT (Subsidence With Influence Function Techniques), has been combined with the expert system to allow the mining factor to be more accurately determined in a broader range of mining layout. Since SWIFT can be calibrated to any particular coal field using local subsidence data, it is believed that the integrated system could be used in any coal field worldwide for the assessment and control of mining subsidence damage risks

Dec 1, 1995

By I. L. Bell

The ironmasters of America had asked the Iron and Steel Institute to visit the USA. The Council decided it was not possible to accept, but Mr. Bell visited; this is an account of his trip. Topics covered include transport, charcoal, coal measures, coal, anthracite, bituminous coal, flux, magnetic iron ore, specular iron ore, limonite, red hematite, clay ironstone, black band ironstone, smelting works, blast furnaces of Pennsylvania, Lake Champlain furnaces, Lake Superior furnaces, Cleveland furnaces, Pittsburg furnaces, Missouri furnaces, and those of the southern states. He goes on to describe Catalan hearths, malleable iron works, Bessemer works, the Blair steel process, and labour.

Jan 12, 1875

By K. Ding

The thermodynamic activity of MnO was measured in MnO-CaO-MgO-SiO2slags that are typically encountered in the production of manganese containing stainless steels. Gas equilibration-quenching technique was employed in measuring the activities. Activity of Mn in Pt-Mn alloys were redetermined at 1600°C which reconfirmed earlier results of strong negative deviations. MnO activities were then measured by equilibrating slags of various compositions based on a statistical experimental design procedure with Pt-Mn alloys under controlled partial pressure of oxygen in MnO saturated platinum crucibles at 1600°C. Activities of MnO were found to increase with increasing concentration of MnO, basicity and CaO to MgO ratio. Two multi-coefficient repression models were developed to predict the activities and activity coefficients of MnO in slags at 1600°C. Keywords: activity, MnO, slag.

Jan 1, 2004

By Peter B. Dowden, Robert A. Robinson

Boulders, frequently found in tunnels excavated through soils, can pose major problems for full face TBMs in terms of slowing or halting the tunnel advance, cutter damage, and abrasive wear. The paper aims to consider the problem as a whole, from the geological characteristics of boulder sites, to the appropriate physical design of theTBM, and its operation in boulder-laden soils. In addition, visualization of boulders and other subsurface obstructions by seismic methods and ground penetrating radar are reviewed. The paper will assist the construction planner in assessing the risks and preparing appropriate specifications.

Jan 1, 2001

By Raymundo Del Carpio

El presente trabajo señala las bases que fundamentan la aplicabilidad del extracto de quebracho como depresor en el proceso de flotación, donde se realiza una combinación de un dispersante (producto obtenido a partir de extractos vegetales). También se muestra los avances sobre procesamiento de minerales con alto contenido de pirrotita. En ese sentido, se busca desarrollar una tecnología eficiente y ambientalmente limpia, considerada como una herramienta para la mejora de la competitividad de la empresa, a partir de una visión de desarrollo sostenible.

Sep 9, 2007

By J. Moskowitz

Construction of the new JFK International Airport Light Rail System (LRS) began in 1998 with a pre-construction load test program. This $1.2 billion design-build project consists of approximately 13 kilometers of elevated twin rail. The elevated rail system is supported on nearly 500 piers requiring deep foundations. The presence of underlying compressible and liquefiable soils as well as space constraints precluded the use of large spread footings. In the 1980's the Port Authority undertook extensive testing to evaluate various piles and drilled shafts types. The LRS piling sub-contractor and the Geotechnical Engineer conducted additional tests for this project to identify the most cost effective deep foundation type. Candidate piles types included: Monotube®, Tapertube®, and closed ended pipe piles. The tapered pile types were found to be the most cost effective and the project utilized both the Monotube® and Tapertube® piles. This paper presents the results of the load test program and the issues related to pile driving induced vibrations and ground movement.

Jan 1, 2000