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By Nagashi Ogushi

Geochemical prospecting method using stream sediments, soils and rock chips has been tested to see the applicability for the typical Kuroko field in Japan. Three independent anomalies have been detected in maps being shown by grav densities of cells which are represented by the results of factor analysis as well as distribution of minor elements scaled in logarithm. A small vein type mineralization which has outcrops could be attributed to the origin of them whereas the one near the surface of known Kuroko deposit to a coincidence. The addition of drill core geochemistry is required to complete the interpretation.

Jan 1, 1982

By K. Harlow

"Zircon is a naturally occurring radioactive material (NORM) and as such is subject to a variety of regulations around the world. The regulatory processes and their implementation are summarized and the key issues affecting zircon and zirconia highlighted. Having absorbed the activities of the former Zircon Minerals Committee, the strategy of the Zircon Industry Association (ZIA) is to be the ‘go-to place’ for information on these matters, and its activities in the NORM space are described. Chemical industry regulations such as REACH are spreading around the world, and the paper provides an update of their status in the key jurisdictions. As mineral sands are transported to market in oceangoing vessels, they are subject to the regulations of the International Maritime Organization, which are summarized in the paper. IntroductionFrom a global perspective, zircon is generally not found in high concentrations other than in placer and dune deposits where it has been deposited along with other heavy minerals such as ilmenite, rutile, and monazite. Such deposits have been sorted and concentrated over geological time by the action of tides, waves, and wind to form concentrated deposits of heavy minerals along old coastlines and in river beds and deltas. Consequently, zircon is mostly found in association with the principal titanium minerals ilmenite and rutile. These secondary concentrations in placer deposits provide the commercial sources of zircon.All geological materials contain natural radioactivity, although the term NORM (naturally occurring radioactive material) is mostly used for minerals and other materials with above-average uranium and thorium concentrations. Importantly, the radioactive nature of zircon has not changed, but the way in which radioactivity is viewed by regulators has, affecting the zircon industry throughout the value chain."

Jan 1, 2017

By P Moswate, D Phillpotts, S M. Mantsho, P Strobos

A challenge on many industrial flotation circuits is controlling concentrate mineral grades using measurements that are provided infrequently. The mineral grades in concentrate streams are a critical performance indicator in any industrial flotation circuit. Failure to achieve concentrate mineral grade targets has significant financial consequences on a flotation operation. A violation of gangue mineral grade limits by the concentrator may also result in significant penalties.Online grade analysers which can provide reliable real time grade measurements are essential for effective grade optimisation. The Blue Cube MQi analyser (by Blue Cube Systems) has recently come to prominence for its ability to rapidly determine mineral concentrate grades online and has the benefit of operating in-stream. This has provided excellent insight into the actual process dynamics in the flotation circuit, and hence enabled real-time control and optimisation of concentrate mineral grades.MintekÆs Measurement and Control division, specialising in advanced control solutions for mineral and metallurgical industries, has had the opportunity to link the FloatStar Grade-Recovery Optimiser to the measurements provided by the Blue Cube system at the BCL nickel concentrator plant in Botswana. The project focused on stabilising the final concentrate grade while ensuring the final tailings are minimised, resulting in an improved nickel recovery. This site already had the FloatStar Grade-Recovery Optimiser for several years, but the original grade measurement device was unreliable and ultimately failed. The system was reactivated once the Blue Cube system was installed, replacing the old analyser. The positive results show the advantages of combining reliable real time measurements with an advanced process control system.CITATION:Mantsho, S M, Moswate, P, Strobos, P and Phillpotts, D, 2013. The implementation of floatstar grade-recovery optimisation control solutions using Blue Cube Online grade analysers on industrial flotation circuits, in Proceedings MetPlant 2013 , pp 575-582 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By Just GD, Gillies ADS

There is an increasing need for reliable and comparable coal resource data and it is necessary to standardize the traditional classification procedures by quantifying the three basic evaluation criteria of economic feasibility, geologic assurance and recovery. For well documented deposits, geostatistical methods can consider- ably improve classification quality. A geostatistically based algorithm for classifying coal resources within the current Queensland and New South Wales codes has been developed. Application of the method in classifying resources from a number of seams exhibiting different structural characteristics is assessed. The method is found to give classification results which closely reflect the error associated with an estimate of resource quantities based on current sampling densi- ties. It requires a careful geostatistical analysis with emphasis on geological awareness. Resource category restrictions must be arbi- trarily assigned and remain constant for all deposits being compared. Engineering judgement is needed and interpretation may be required with isolated and peripheral blocks.

Jan 1, 1987

By C. Xiao, R. Chi

In recent years, the biosolubilization of rock phosphates by phosphate-solubilizing microorganisms has become a major topic of research studies. However, the microorganisms used in previous studies were mostly single and known species, and studies seldom focused on mixed communities of microorganisms or microbial consortia from natural environments. In this study, a microbial consortium from rhizospheric soil was used to solubilize two different compositions of medium- to low-grade rock phosphates — designated as ore samples 1 and 2 — in a laboratory-scale bioreactor. The microbial consortium showed good growth in the bioreactor, reduced the suspension pH and released soluble phosphates from the ores. Scanning electron microscopy with energy-dispersive X-ray spectroscopy showed the action of the microbial consortium on the ore surface. There was considerable corrosion on the ore surface, and 3.42 and 4.93 percent of the element phosphorus was removed from ore samples 1 and 2, respectively. Microorganisms were sampled from the bioreactor for the analysis of their community structures by Illumina MiSeq high-throughput sequencing. The analysis show that the suspensions added with different ore samples had different microbial diversities and richness. This study provides new insight into the biosolubilization of rock phosphates by a microbial consortium directly taken from rhizospheric soils.

"Drilling twinned holes is a traditional technique used for verification of intersections of high-grade mineralization, testing of historic data, or confirmation of drillhole data during geological due diligence studies. Twinned holes can also be used for special tasks such as correcting earlier data that are recognized to be biased. Successful implementation of the twinned-holes technique requires thorough planning. Experience suggests that good practice is to drill twinned holes no more than 5 m apart. Many unsuccessful twinned-holes programs could possibly have failed because the twinned holes have been drilled too far apart.Twinned holes are best compared by mineralization intersections and, if the data and geological characteristics of the deposit permit, by samples, equal-length composites, or geological units. Variables to be verified by twinned holes should include the thicknesses of the geological units of interest (e.g., mineralized thickness) as well as the presence of significant geological features (e.g., ore/mineralization contacts, alteration, etc.).A formal, rigorous analysis of twinned-hole data is essential. Repeatability of sampling, analytical results, and bias must be analyzed and statistically quantified. The number of twinned holes required for conclusive statistical and geostatistical analysis can be as high as 20-30, in particular where the studied variables are characterized by high short-range (local) variability.The efficiency of this approach is demonstrated by several examples of successfully applied twinned-hole projects, including applications to orogenic gold, mineral sands, bauxite, and iron ore deposits."

Jan 1, 2009

By F. W. Gray

Foreword: It is not my purpose, in this address, to write the history of the Geological Survey of Canada, which has from time to time been reviewed by the officers of the Survey itself, and by men more competent than myself to handle so large a subject, but rather to set out some of the reasons for the regard in which the Survey is held by our Institute, the body best qualified to speak for the mining men of Canada. And, a further purpose is to publish the desire of our Institute that the work of the Survey shall be maintained at the highest pitch of efficiency the resources of our country. will permit, because to scrimp expenses on the Survey is 'to save at the spigot and lose at the bunghole." A historical examination of the grounds on which it may be asserted the Geological Survey has been, and still is, of fundamental economic value to our country, discloses a prescience on the part of the forefathers of Canada, calling for our admiring gratitude, and reveals a unanimity among the real leaders of Canadian thought, on the value of geological knowledge, that is impressive in its continuance dawn to this date. There seems always to have been before our people the realisation that large stretches of Canada are unfitted for agricultural settlement, and that our glaciated areas, the barrens and tundra of the North, and our extensive mountain ranges, had promise of compensating mineral content which the geologist and the prospector, labouring together through the years, would disclose. The Geological Survey is one of Canada's oldest public services, distinguished by an unimpaired tradition of honourable and useful labour. Founded in 1843, under William Edmond Logan, not yet 'Sir William', one year after the Act of Union, it was directed by him until 1869, or into the early years of Confederation, so that the early years .of the Survey were also, politically, the formative years of Canada, as we know her today.

Jan 1, 1932

By Sandip K. Mukherjee, Anthony W. Laurito, Madan M. Singh, Jon C. Volkwein

In the past, little attention has been paid to the costs of ventilation, since it seldom represented a significant portion of the total mining cost. However, in recent years adverse mining conditions and increases in power charges have caused ventilation costs to rise. The federal regulations have set minimum standards for volumetric airflow rates in underground coal mines. As a mine develops, the air volume and pressure requirements increase. There are several methods by which the quantity of airflow to the mine and working faces can be increased. Some of the methods include (1) increasing main fan output or replacing the main fan by a new higher capacity fan, (2) reducing leakage across stoppings and overcasts, (3) adding a new ventilation shaft or borehole, (4) reducing resistance to airflow by reducing the resistance factor of the individual airways, increasing the number of airways (especially the parallel airways), or re- arranging the air courses by using the available entries, and (5) using auxiliary ventilation systems. This paper addresses the cost-benefit analysis of several of these alternatives as applied to a large operating coal mine located in southern Illinois. Pressure and quantity surveys were conducted under-ground, and measurements were taken at the main exhaust fans on the surface. The existing ventilation network was modeled by using the Penn State ventilation simulator. The input data included the configuration of branches, resistance of each branch (including a component for shock losses), and changes in pressure and volume. The results of the simulation were compared with the survey data to check the merits and accuracy of the model network. The net- work was designed to take into account shafts, major entries, overcasts, regulators, gob areas, working faces, and major leakage paths. The model network served as the basis for the cost analyses of networks designed for increased airflow. The applicable alternatives for increasing airflow were simulated. Performance data obtained from these simulation runs were utilized to conduct the cost-effectiveness analysis. The costs for each f the alternatives included capital, operating and maintenance costs. These costs were expressed as annual costs in terms of dollars per cfm of circulating air, taking into account the economic life associated with each of the alternatives. The benefits were expressed as increased airflow quantity in the critical sections. The result of these analyses show that for the short-range plans evaluated, the most cost-effective way of increasing airflow at this mine would be to reduce leakage through stoppings and overcasts.

Jan 1, 1982

By H. N. Thomson

(Butte Meeting, August, 1913.) GENERAL. THE Tooele plant. off the International Smelting & Refining Co. is situated at the mouth of Pine canyon, Tooele county, Utah. It is connected with the main line of the San Pedro, Los Angeles & Salt Lake railroad by the Tooele Valley. railway, and is about 7 miles from Tooele Junction. Fig,. 1 is a general view of the plant. The copper plant has been in operation since July, 1910, and the first blast furnace it the lead plant was blown in on Feb. 29, 1912. The location of the plant was selected on sloping ground with the idea of using gravity to the fullest extent and thus keeping labor at a minimum. Practically the entire plant is constructed of steel, reinforced concrete, and. brick.

Jan 7, 1913

By L. A. Maseko

"As part of the mining engineering curriculum, students are required to be placed in industry for vacation work or work-integrated learning (WIL). In this paper we review work-based placement as done at the four South African mining schools: the University of Johannesburg, the University of Pretoria, the University of the Witwatersrand, and the University of South Africa.Key aspects of past and current WIL (pre- and post-graduation) practices that may need attention are highlighted for consideration by all universities that provide professional qualifications. Work-directed theoretical learning, problem-based learning, project-based learning, workplace learning, and simulated work experiences are discussed as legitimate approaches to WIL.Regardless of the choice each institution makes, commitments of universities, preparedness of university teachers, and the desire for equity and excellence will play an important role in the provision of WIL.DefinitionsAccredited Qualification: a qualification awarded on successful completion of an accredited programme.Advisory Boards (or Committees): are essential infrastructure for a WIL curriculum that is built on the integration of the workplace and the university. This requires the collaboration of experts from both environments. Workplace advisors are critical to the success of the academy as they embody expert knowledge of the ‘real world’.Assessment: the process of determining the capability or competence of an individual against standards by evaluating performance.Category: a mode of registration defined in or under the ECSA Act which has a distinctive purpose, characteristic competencies, defined principal routes to registration, and educational requirements.Experiential learning: (in South Africa sometimes used synonymously with work placement or cooperative education) is a term used with a great variety of meanings in the international literature. More broadly, it may refer to learning that has meaningful learner involvement. It is the process of generating meaning from direct experience. In the international literature, experiential learning is learning through reflection on doing, which is often contrasted with rote or didactic learning."

Dec 1, 2018

D. HARRINGTON: Owing to lack of funds, the United States Bureau of Mines have made no experiments in the Bruceton mines in the use of mudite. MR. McAULIFFE: I doubt that mudite cam be delivered at fifty cents a ton and that a mile of heading can be treated with mudite for ten dollars. You could not dig a ton of sand out of a sand hank for that money. L. C. CLARE: The tram road leading to Wattis mine crosses a shale bed and it is easy to screen the shale through a %-inch sieve and load it into a mine car. W. J. REID: A slow trip passing through a mudited entry will dislodge practically no dust, a rapid trip will make air disturbance enough to coat the cars with fine dust. MR. PRYDE: We have used mudite on stoppings around a fire in Reliance and for two months thought they were getting good results, but the fire was found to be drawing air and to be spreading. This mudite was smeared over the stoppings with a trowel. After this apparently failed we used dry adobe.

Jan 1, 1925

By Samir Kumar Pal, Rajasekar Rathanasamy, Gobinath Velu Kaliyannan, Moganapriya Chinnasamy, Sathish Kumar Palaniappan

The research examines the performance of uncoated and coated tungsten carbide-cobalt rock cutting bits. It aims to optimize process variables (cutting speed, depth, coating material) considering multiple output responses (cutting forces, specific energy, wear rate, material removed, angle of reaction forces). The study uses a hybrid optimization technique combining Taguchi design, grey relational analysis, and fuzzy logic. The optimal parameter combination was found to be cutting speed: 200 mm/s, cutting depth: 6 mm, and titanium aluminum silicon nitride coating.

Apr 24, 2022

By J. W. Paul

This paper deals with the third phase of on extensive research on coal-mine ventilation factors. A comprehensive report of the entire work is in course of preparation, but abstracts of the various chapters are being prepared in order to make the results public as rapidly as possible. Parts I and II of this paper were issued Serial 2621 and Serial 2647 of the Bureau of Mines in July and October, 1924. They dealt with the resistance of unobstructed entry and the resistance caused by mine cars in untimbered entry. Description of the Tests After the resistance of unobstructed entry and of mine cars in untimbered entry had been determined by tests in the Experimental Mine, three different types of timbering were installed in the test section and the increased resistance caused by the timbering was determined.

Jan 1, 1925

By A. C. Neiva

An energy-dispersive x-ray fluorescence spectrometer was assembled with the aim of analysing alloys and corrosion products of artistic, ethnological and archaeological pieces. The spectrometer is semiportable and consists basically of an 60kV/1.5mA X-ray tube with W anode and a Si-drift X-ray detector with Peltier cooling, with no need of liquid nitrogen. It was used for the analysis of the alloys and occasional corrosion products of several metallic pre-Hispanic pieces of the Museum of Ethnology and Archaeology of the University of São Paulo. Special care was taken to account for the contribution of spurious radiation from both the Pb primary collimator and the Zr detector collimator. The main components of most alloys were Au, Ag and Cu, but Pb, Ca, Fe and other elements were also identified. The characterization of the alloys and corrosion products is important for the subsequent conservation of the collection.

Jan 1, 2006

By A. L. Mular

In order to simulate a grinding circuit, it is necessary to obtain valid mathematical models of the grinding mills and classifiers in the circuit. Several models of grinding mills Ova been proposed 1,2,3 and models of cyclone classifiers are available 4,5. Those models developed by Lynch et. al. 3,5 have been tested in the plant, so that some degree of reliability can be placed on them. Because of this, it is reasonable to assume that the Lynch models will apply for a given circuit, and then to test this assumption. Empirical modifications are made as necessary for a given situation. Usually, valid simulation models can be modified slightly to provide control models6,7. The purpose of this paper is to describe the results of an approach taken by Mular8 to obtain the Lynch models of parallel cyclone classifiers being used in the A-circuit of the new Strathcona Mill***.This was one of the projects undertaken by the fourth year Metallurgical Engineering Class of 1969, Queen's University, Kingston, Ontario, Canada, as part of their process design course which cooperates closely with the Canadian metallurgical industry.

Jan 1, 1970

By R. A. Perry

DURING 1943, supplies of lead, like those of most base metals, moved from a position of scarcity to one of ample supply for all possible war requirements. The principal worry in the market, as 1944 began, was that surplus stocks might increase too rapidly to maintain price stability. The problem of postwar stockpiling had definitely entered the picture. The end of the year finds the lead industry having met all use demands, but not without depleting stocks to a critical low in spite of heavy importations. The principal reason for this dangerously reduced stock position is lack of adequate man power, which, without question, has become the lead industry's number one problem. This condition became obvious about the middle of the year, after Selective Service placed in effect orders that no deferments would be given employees under 26 years of age, and to a complacent attitude toward the industry assumed by the War Manpower Commission. It has become progressively worse since then. The WPB continued its policy, started during 1943, of easing restrictions on materials to be used for maintenance, repairs, and operating supplies. The policy of premium payments established by the Metals Reserve Co. was continued and, in spite of expressions to the contrary, has proved quite satisfactory. In short, the Government continued its program of stimulating the lead industry in practically all

Jan 1, 1945

By Shiou-Chuan Sun

The froth flotation of coal, differing greatly from that of most minerals1-5, is not improved but rather impaired by temperatures higher than room temperature6-10 This phenomenon has long taunted us for an explanation. Gayle and Associates 8,9 reported the lack of relationship between their contact angle measurements and their flotation of American coals under various temperatures. Bailey and Whelan6 stated that the viscosity of flotation reagents, offering some clue for their flotation of British coals at low temperatures, could not be put forward as an explanation either in whole or in part for the effect of temperatures on coal-flotation. In this paper, a froth hypothesis is proposed to explain the flotation behavior of coals under various pulp temperatures. Test work involved the flotation of coals and the frothing of reagents.

Jan 1, 1966

By A. E. Koski

This paper describes the implementation of specialized software in mine planning at the Cleveland-Cliffs’ managed Empire Mine on Michigan’s Marquette Iron Range. The application puts together years of mining experience on the eastern end of the Marquette Range beginning in the early 1960’s. The Empire Mine, in its thirty-fifth year of production, uses the software to model a complex and highly variable low grade magnetite orebody, capturing the economics of mining and processing to the final product. With special attention given to geostatistical methods, the software is used for all geologic modeling, ore reserve estimation, ore control, pit design and short and long range planning.

Jan 1, 1999

By Jesús Carrasco, Matilde Alvarado, Miguel Segur

El presente trabajo, tiene como fin, mostrar el valor que tiene la naturaleza en las decisiones de gestión y gobernanza, más allá del valor del suelo o superficie, al aplicar Soluciones Basadas en la Naturaleza (SBN), que por ejemplo pueden ser restauración de ecosistemas degradados, la conservación de áreas protegidas, la gestión sostenible de los recursos naturales, entre otras. Dado que el trabajo se encuentra en desarrollo, los resultados preliminares de la caracterización legal, social y ambiental muestran los primeros pasos para poder identificar los predios disponibles en donde se buscará implementar SBN.

Sep 29, 2023

By K. J. Gill, P. Chiotti, J. T. Mason

Thermal, metallographic, and vapor pressure data were obtained to establish the pkase boundaries and the standard free energy, enthalpy, and entropy of formation for the compounds in the Y-Zn system. Three coinpounds with stoichiometric formulas of YZn, YZn2, and Y2Zn17 melt congruently at 1105", 1080°, and 890°C, respectively. Four compounds with stoiclziometric formulas of YZn3, YZn4, YZn5, and YZn,, undergo perztectic reactions at 905", 895", 870º, and 685ºC, respectively. Three eutec-tics exisl in this system with the .following eutectic temperatures and zinc contents in wtpct: 875ºC, 23.2 Zn; 1015ºC, 51 Zn; 865ºC, 82 Zn. The YZn, pkase undergoes an allotropic transformation. In the two phase YZn2 -YZn alloys the trans.formation gives a weak thermal arrest at 750°C, whereas in the two phase YZn2-YZn3 alloys no thermal arrest is observed and the transformation occurs over a temperature range below 750°C. At 500°C the free mzergies of formation per lnole vavy from —18,090 for YZn to —53,430 fov YZr11 and corresponding enthalpies vary from -24,050 to -92,080. The free energies and enthalpies per g atom as a function of composition show a maximum for the YZn2 phase; the 500°C values are -9580 and -13,180, vespectively. 1 HE only information found in the literature on Y-Zn alloys was the observation reported by Carlson, Schmidt. and speddingl that Y-20 wt pct Zn forms a low melting alloy. The alloy was produced by the bomb-reduction of YF3 and ZnF2 with calcium in an investigation of methods for producing yttrium metal. The solubility of yttrium in zinc has been determined by P. F. woerner2 and reported by Chiotti, Woerner, and Parry.3 In the temperature range 495" to 685°C the solubility may be represented by the relation In these equations N represents atom fraction of yttrium and T is the temperature in degrees Kelvin. The purpose of the present investigation was to establish the phase diagram for the Y-Zn system and to determine the standard free energy, enthalpy, and entropy of formation for the compounds formed. MATERIALS AND EXPERIMENTAL PROCEDURES The metals used in the preparation of alloys were Bunker Hill slab zinc, 99.99 pct pure, and Ames Laboratory yttrium sponge. Arc-melted yttrium buttons contained the following impurities in parts per million: C-129, N-12, 0-307, Fe-209, Ni-126, Mg-13, Ca < 10, F-105, and Ti < 50. Some of the alloys containing 70 wt pct or more of Zn were prepared from yttrium containing 5000 ppm Ti as a major impurity. Tantalum containers were found to be suitable for all alloys studied and were used throughout the investigation. The pure metals, total weight about 30 g, were sealed in 1 in. diam tantalum crucibles by welding on preformed tantalum covers. A 1/8 in. diam tantalum tube was welded in the base of each crucible for use as a thermocouple well. Welding was done with a heli-arc in a glove box which was initially evacuated and filled with argon. The sealed crucibles were enclosed in stainless steel jackets and heated in an oscillating furnace at temperatures up to 1150°C. Homogeneous liquid alloys were obtained within a half hr at these temperatures except for alloys containing less than 20 pct zinc. The latter alloys were held at 1000º to 1100°C for 2 to 3 days in order to obtain equilibrium. After the initial equilibrations the tantalum crucibles containing the alloys were removed from the steel containers and used directly for differential thermal analyses. Further annealing heat treatments for alloys in which peritectic reactions were involved were carried out in the thermal analyses furnace. After thermal analyses the tantalum crucibles were opened and the alloys sectioned and polished for metallographic examination. In the following discussion alloys referred to as "quenched" were obtained by quenching the sealed stainless steel jacket containing the tantalum crucible and alloy in water. The differential thermal analyses apparatus used was a modified version of the one described in an earlier paper., The graphite crucible was replaced by an inconel crucible, the nickel standard and sampie container were separated by a 1/8 in. MgO plate, no getter was used, and provisions were made to

Jan 1, 1963