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By Alfred Bodenlos

El presente texto señala los depósitos de plomo, zinc encontrados en la mina Huallpac, Macón, Cerro Plumisa; los cateos del área de la laguna Shagallán, Uchco, cateo del cerro Cieren y la mina Buena Casma y Mangán, pertenecientes a la Cordillera Negra, ubicado en Ancash, Perú.

Jan 1, 1958

By Christopher F. Gleeson, Roger D. Thomas

"Abstract - Wawa has long been a center of mineral exploration activity and diamonds have been reported in the area since the 1930s. However, diamond exploration did not begin in the area in earnest until 1991. In 1993, Sandor Surmacz and Marcelle Hauseux of Saminex began a prospecting program in the area which culminated in their discovery of the "Sandor" diamond occurrence in an outcrop on the east side of the Trans-Canada Highway. They subsequently optioned the property to Spider Resources Inc. who obtained the necessary exploration permits from Algoma Central Corporation and undertook an exploration program. The diamonds at the "Sandor" diamond occurrence are hosted in the matrix of a spessartite dike composed of actinolite, biotite, and albite. Of the 64 similar dikes that have been sampled and analyzed to date, eight have been found to contain a total of 231 diamonds. Most of the diamonds are of high quality, although they are small.The dikes are non-magnetic and do not have any other geophysical characteristic that can be used to differentiate them from the adjacent country rock. All of the dikes discovered to date have been found by prospecting or by geological mapping by the Ontario Geological Survey. The dikes do not contain pyrope garnet or chrome diopside, two of the commonly used kimberlite indicator minerals. Instead, low Mg, high Cr, Zn-rich chromite, and ilmenites of variable composition, some of which lie within the field of kimberlitic Mg-ilmenite compositions, characterize the diamondiferous dikes. A regional-scale till sampling program for heavy minerals, and geochemical analysis of the <0.177 mm fraction, was used to further define the areas of occurrence of the spessartite dikes and to indicate additional areas for diamond prospecting. Heavy minerals in till that were most useful include: actinolite, chromite, and ilmenite. Geochemical analyses of the dikes show them to contain elevated concentrations of Ni and Cr and to be enriched in Ba, Co, V, Ca, Fe, and Mg relative to the surrounding rocks. Elevated concentrations of Ni and Cr in till occur overlying and down-ice of known lamprophyre dikes."

Jan 1, 2000

By Henry P. Chandler

[Diamond, because of its extreme hardness and abrasion resistance, has an important function in precision engineering and automation. With the increasing; requirements of modern production for fine tolerances, interchange-ability, and speed, it has become even more important. In spite of the supply of other abrasive and hard materials and of ultrasonic, electrospark rued other substitute grinding, methods, world industry seams likely to absorb large quantities of diamond for industrial purposes. An increasing part of the world&apos;s needs will be supplied by manufactured diamond, which was introduced commercially by General Electric Co. in 1957. Use of diamond for glass cutting roes bark several centuries, mid diamond drilling of rock became important to the mining industry M the 1870&apos;s. Today, diamond drilling is the most extensively used method of exploring the world&apos;s ore reserves; diamond drills two also used to determined the nature of bedrock below the foundations of buildings, dams, and bridges. Diamond drill bits are now used extensively in the petroleum industry, and replacement or steel rock bits with diamond drill bits in hard rock formations has affected substantial savings.]

Jan 1, 1964

By Edward Sampson

Bases of National Power At a time when the economy of the world is in a particularly troubled state it is appropriate to examine some problems of the distribution of natural resources. I should like particularly to call attention to the remarkable increasing demand for natural resources, to give an analysis of the demand for certain mineral resources, and to direct attention to some problems in satisfying this demand. All industrial power is based on natural resources and the most basic of these are soils, energy resources, and mineral resources. There is a strong interrelation of these resources, more than is obvious, and I shall take up certain aspects from the point of view of a geologist. Few nations are well endowed with all three of the kinds of natural resources I have mentioned and much has been done by some small countries whose peoples are industrious and enterprising and where conditions for free world trade have been favourable. However, major industrial power is dependent on a substantial endowment of all three classes.

Jan 1, 1949

By M. Abdellatif

The production of a 40% Al-Ti alloy was successfully proven at the lab scale, using pure TiO2, aluminium, and lime. These tests were conducted in an induction furnace maintained at 1600?16250C. The introduction of rutile into the feed recipe resulted in an alloy containing between 0.35 and 1.10% Zr, depending on rutile to TiO2 ratio. DC arc production of the alloy was largely accomplished at 40 and then 200kW scale. These tests evaluated various metallurgical and operational factors including target slag composition, Ti-content in the alloy, co-feeding versus sequential, furnace bath depth, and rutile as part of the Ti containing feedstock. Overall, an alloy containing 24?33% Ti was consistently produced with co-feeding of the reactants and with lower taphole tapping. When rutile was added, the zirconium analysis in the alloy remained below 0.2%. The main impurity elements were iron, silicon, carbon, nitrogen, and oxygen.

Jan 1, 2009

By Mirza Muhammad Zaid, Nana A. Amoah, Ping Chang, Guang Xu, Ashish R. Kumar

The key takeaway of this study is the significant improvement in dust protection for roof bolter operators in underground coal mines. The optimized canopy air curtain (CAC), with a redesigned two-level manifold system, provides uniform airflow distribution that effectively reduces dust exposure. By enhancing the protection of operators from harmful respirable coal and silica dust, this technology can reduce the risk of diseases such as coal workers’ pneumoconiosis (CWP) and silicosis. The application of this optimized CAC design in real-life coal mining operations can dramatically improve worker health and safety by minimizing dust-related exposure, ensuring compliance with industry regulations and prolonging the lifespan of mining equipment by reducing dust accumulation.

Dec 1, 2024

In the last 30 years, human appropriation of global renewable resources has accelerated to the point where 35 per cent of the earthÆs land surface is now in managed agro-ecosystems, consumptive water use consumes between 50 per cent and 85 per cent of freshwater supply and 60 per cent of ecosystem services are utilised in an unsustainable manner. There are virtually no landscapes in which renewable resources are not already fully allocated among different economic and environmental uses. Furthermore, it is increasingly recognised that water availability issues do not exist in isolation but are linked with the related environmental issues of biodiversity preservation, the carbon cycle, soil degradation, and energy use and supply. It is against this background that the sustainable management of water in mining is increasingly developing a strategic viewpoint where water is viewed as a resource within an interconnected landscape, having economic, environmental and social value and providing a range of environmental services in the provision of public and private goods. This paper explores the issues associated with sustainable management of water in mining from a strategic viewpoint. The cumulative impacts of multiple water users, both within and outside the mining sector, is increasingly threatening the security of supply for all users. To quantitatively assess the ætrueÆ value of water it is necessary to: Better understand the science of ecosystem functioning and how human actions impact on environmental processes. Develop appropriate policy, finance and governance structures to support innovative programs that preserve ecosystem function and services (including market based instruments). Apply knowledge as interventions across landscapes in ways that maximise benefits and minimise unintended consequences taking into account differences in the value of water among sectors. A strategic viewpoint of water management relies on knowledge to guide decision making that has been acquired at a range of scales from mine site to mining region. This knowledge must be based on rigorous science, sound data and syntheses of different types of information. Strategic management of water resources will better position the industry in terms of understanding the risks posed by complex, interlinked environmental issues that are increasingly impacting on future access to land and renewable resources, including water, thereby ensuring miningÆs future social licence to operate.

Jan 1, 2009

By Leonardo Flores

"Minera Escondida operates two open pits on a porphyry copper district, southeast of Antofagasta, Chile. During 2005, ore will be delivered exclusively from one pit to two concentrators, while from 2006 both pits will provide ore to these plants. Annual testing programmes on drillhole samples, have allowed for the construction of hardness block models since 2000. These models have delivered two main hardness descriptors, the Bond work index and the SAG power index. These parameters and plant operational specifications have been used as input information to forecast, the expected throughput and ball mill product size (P80) for each block of ore. Two forecasting techniques have been used, an in house model, strongly dependant of bond work index and MinnovEx´s CEET2, dependant of Bond work index and Sag power index and other parameters. Model performance has been evaluated from reconciliating on a monthly basis, the forecasted throughputs against a recalculated plant throughput which accounts for losses in tonnage not caused by ore hardness but instead by unscheduled plant operation problems. The model performance for 2003 was ± 2% yearly and ± 5% quarterly, well within the expected ± 3% and ± 10%. INTRODUCTIONThe Escondida porphyry copper district is located 140 km SE of Antofagasta, Chile at 3150 m.a.s.l, at 24°16’ South latitude and 69°04’ West longitude (figure 1)."

Jan 1, 2005

By Bruce Vandenberg

A 3D, PC based computer program is currently under development by Blasting Analysis International, Inc., to analyze the kinetics of full scale blasts with two or more high-speed motion picture cameras.

Jan 1, 1990

The development of Western Mining Corporation&apos;s first commercial gold heap leaching operation is described. The laboratory testwork requirements for determining the amenability of ore to heap leaching techniques is discussed. Heap construction and operating practices are described; and production statistics and operating parameters are presented. It is shown that for a specific low grade gold ore a treatment cost optimization can be performed. Taking cognizance of the ore grade, percentage gold recovery, operating costs, and the gold sale price, it can be determined whether Carbon-In-Pulp (C-I-P) or Heap Leaching should be employed as the extraction process. The examples presented in this paper refer specifically to Kambalda and should not be used in themselves as generalities.

Jan 1, 1987

By José Wilmar Calderón-Hernández

Aços inoxidáveis supermartensíticos (AISM) surgiram em meados dos anos 1990, após algumas empresas petroleiras e centros de pesquisa empreenderem projetos para desenvolver aços inoxidáveis com boa resistência mecânica e resistência à corrosão. A força motriz destes projetos foi a procura de aços inoxidáveis alternativos para os aços duplex e superduplex na extração de reservas de petróleo “offshore”, devido a seu alto custo e a problemas de produção naquela época. Os AISM são derivados dos aços martensíticos inoxidáveis convencionais, possuem menor teor de carbono, para permitir melhor soldabilidade e melhorar a resistência à corrosão, adição de níquel para evitar a presencia de ferrita delta (d) e adição de Mo, que também aumenta a resistência à corrosão. Através de ensaios de polarização potenciodinâmica foi avaliada a resistência à corrosão de um AISM 13Cr-5Ni-2Mo, denominado neste trabalho como AIS_2Mo, para três diferentes ambientes, NaCl, NaCl+CO2 e NaCl+H2S (soluções desaeradas). O material foi recebido como chapas laminadas a quente, as quais foram normalizadas a 1.050°C (½ hora/ar) e posteriormente revenidas a 600°C (2 horas/óleo). O melhor desempenho foi observado no eletrólito contendo apenas NaCl, com potencial de pite ao redor de 40 mV (ECS); o ambiente mais agressivo foi a mistura NaCl+H2S, com potencial de pite ao redor de -300mV (ECS), a mistura NaCl+CO2 teve potencial de pite intermediário, com valor 60 mV (ECS) abaixo do eletrólito contendo só NaCl.

Aug 8, 2018

The 109th Annual General Meeting of The South African Institute of Mining and Metallurgy was held at The Country Club, Johannesburg, Napier Road, Auckland Park on Wednesday, 16 August 2006. Special General Meeting A Special General Meeting to consider the changes to the Constitution was held immediately prior to the AGM. 1. Purpose In order for the SAIMM to remain relevant and ensure maximum value to all members, Council propose three changes to the Constitution. 2. Background Three changes to the Constitution were proposed by the Council on 21 July 2006. These changes now have to be approved by means of a ballot at a Special General Meeting. These three proposed changes are discussed briefly below:

Jan 1, 2006

By L. K. Witika, J. H. Masinja

"Investigations of flotation characteristics of Lumwana and Kansanshi ores using formulated frothers were carried out. Of the six frothers tested, two came from the alcohol family, two from the glycol family and last two were formulated products. The initial work involved determining the optimum mesh of grind and frother dosage for Lumwana and Kansanshi ores. Further work involved carrying out surface tension, bubble size and froth stability measurements. Finally, water recovery tests were conducted at Lumwana and Kansanshi mine sites. For froth stability tests, six frothers were tested on a two-phase (water–air) system using the Bikerman column flotation cell, while water recovery tests were conducted using a total of seven frothers, including the standards for each plant. The results of the testwork showed that (i) although a stable froth is essential for optimum recovery of valuable minerals, a higher molecular weight frother, like Dowfroth 250, caused poor selectivity when used on fine ores and (ii) a lower molecular weight frother was suited for Lumwana ore, while a mid to higher molecular weight formulated product was suitable for Kansanshi sulphide ore. INTRODUCTION Investigations of flotation characteristics of Lumwana and Kansanshi ores using formulated frothers were carried out. The initial work of this project involved determining the optimum mesh of grind and frother dosage for Lumwana and Kansanshi ores. Further work involved carrying out surface tension, bubble size and froth stability measurements. Finally, water recovery tests were conducted at Lumwana and Kansanshi mine sites. In order to investigate the gangue entrainment levels in the Lumwana and Kansanshi sulphide ores, two well-known methods (froth stability and water recovery) were used. Firstly, froth stability tests were conducted using six frothers, two from the glycol family (Dowfroth 200 and Dowfroth 250), two from alcohol family (MIBC and pine oil) and other two from the formulated family (Betafroth 20 and Betafroth 245), at the University of Cape Town’s Centre for Mineral Research (CMR) laboratories. Froth formation and stability measurements were conducted using the Bikerman column flotation cell."

Jan 1, 2015

By D. C. Oldroyd

Western Coalfield?s Tandsi Mine, has difficult support conditions and a history of roof falls, resulting in mining roadway widths and depths being restricted for safety reasons. Rock Mechanics Technology Ltd was contracted to improve the support system to allow the introduction of mechanised room and pillar mining. The introduction of a ?world best practice? bolting system resulted in major improvement in roof stability, allowing mining restrictions to be lifted and Tandsi to become one of the first two Indian mines to introduce a mechanised continuous miner system. The first year?s production was some six times previous levels. Because of the improvement in the support system, RMT was also able to design a partial de-pillaring system suitable for the Tandsi continuous miner districts together with the introduction of monitoring procedures and guidelines to maintain safe roof support conditions. In situ monitoring of pillar and roof behaviour was undertaken as the first pillars were extracted to confirm the design. De-pillaring operations have also proved highly productive, and to date there has been no associated support related major injury or dangerous occurrence. The success of this project demonstrates the potential for mechanised room and pillar mining in India.

Jan 1, 2006

By R. S. Olsen

Although aluminum is easily leached from calcined clay with boiling mineral acids, the presence of fines and slimes in the leached residue has hindered the application of acid leaching processes. A feed preparation method was, therefore, devised that provided a dense, smooth-surfaced, fine-grained clay. The important factors affecting feed quality were determined to be (1) crushing the raw clay to the size desired for the leaching process, (2) moistening the crushed clay with a fine mist of water while tumbling on a rotating disk, (3) drying the misted clay, and (4) calcining the dried clay at 750° C in a fluidized bed. Clay treated by this method was leached with HCI, and its residue was washed by water displacement in 4-ft-deep beds. Bed permeabilities on the order of 47 darcys or 4.6 x 10-7 cm2 were obtained with the leached residues.

Jan 1, 1983

By C. J. Martin, M. P. Hay

"A methodology was developed in the mid-1980’s to predict plant performance from standard laboratory flotation tests. The technique is based on a simple, empirical kinetics model, and is tailored for use by the practical metallurgist.To date the performance of more than 20 flotation plants has been predicted, including copper, lead, zinc, phosphate, pyrite, graphite, cassiterite, platinum, nickel and various slags. The method has successfully been used to predict and size four flotation plants directly from bench-scale laboratory flotation testwork. All have since been commissioned, and have performed as predicted.The technique has now received broad acceptance within the South African mining industry, for example in the last year alone it has been used to drive flowsheet development for at least seven new plants. It is also being used to assist in the optimisation of existing operating plants.The methodology is described in this paper and verification of the methodology is presented using case studies of porphyry, polymetallic and PGM operations.INTRODUCTIONThere is considerable interest these days in the use of modelling to simulate flotation circuits, for process design and plant optimisation purposes. Although these models are proving to be useful tools for plant design and optimisation, their complexity can make them cumbersome – expensive to use and difficult for metallurgists to visualise and mentally absorb, without a background in each specific technique. In “SUPASIM” no attempt is made to measure flotation fundamentals, rather to use empirical relationships between laboratory flotation kinetics and plant performance – relationships that hold up well to validation exercises as will be demonstrated later in this paper. Although not designed to be as comprehensive as other models, “SUPASIM” is easily understood by the operating metallurgist and can be quickly and easily applied."

Jan 1, 2004

The process of gold recovery by gravity concentration is incorporated in the metal recovery flowsheet at seven Newmont Mining Corporation owned mining operations in Australia, North America and Africa. In 2009 gold recovered by gravity processing was equivalent to nine percent of Newmont&apos;s total gold sales of 5.3 million ounces. This paper will discuss these applications in detail including a review of plant flowsheets and presentation of recent operating results. Operating performance will be discussed with reference to ore characterisation procedures, interpretation of results, design considerations and optimisation practices as they relate to the recovery of gold by gravity concentration.

Jan 1, 2011

By Arno C. Fieldner, J. W. Paul, WALTER A. SELVIG

Many mine samples of coal are analyzed each year in the laboratories of the Bureau of Mines. The analyses are made in connection with investigations relating to fuels belonging to or for the use of the United States Government, the causes of accidents in coal mines, the geologic relations of coal beds, and the quality and the value of the coal and lignite in the public lands. The systematic collection and analysis of such samples in connection with fuel investigations was begun in 1904 at the Government fuel-testing plant at the Louisiana Purchase Exposition. and was under the direction of the United States Geological Survey for six years. Descriptions of the coal samples collected between the beginning of this work, July 1, 1904, and the transfer of the fuel-testing and mine-accident investigations to the Bureau of Mines,July 1, 1910, were compiled and published in Bureau of Mines Bulletin 22.' Descriptions and analyses of samples collected during the fiscal years 1911 to 1913 were published in Bureau of Mines Bulletin 85.2 Descriptions and analyses of samples collected during the fiscal years 1913 to 1916 were published in Bureau of Mines Bulletin 123.3 The present bulletin presents analyses and descriptions of samples collected during the fiscal years 1916 to 1919. In order that the material in this bulletin may be used to supplement that presented in Bulletins 22, 85, and ,123, the same plan of geographical classi- fication has been followed, the analyses and descriptions of the samples being grouped in alphabetical order according to the State, county, and town near which the mines or prospects sampled are situated.

Jan 1, 1922

By H. J. Siriwardane

This paper presents results from three case studies involving longwall mine panels at which the measured ground movements were compared with the numerical model predictions based on the finite element method. A new approach called the "displacement approach" was used in this study. The general concept of this method is based on the assumption that total roof collapse occurs behind the mine face as it advances. This assumption appears to be true for almost all longwall mining conditions. The prediction based on the numerical model appears to compare well with the measurements.

Jan 1, 1988

By T. Hollenberg, N. Nolten

The mining industry is one of the major energy consumers in Namibia. Energy costs increase the operating costs of Namibian mines, in particular, the processing plants, and result in an overall increase of production costs. A substantial part of the energy used is directly imported from South Africa. The cost of energy has been increasing rapidly in the past few years and will most likely continue to do so in the future. In 2015, the average wholesale price for energy from national power utility NamPower was US$87/MWh after rising more than 12 percent annually in the two previous years. At peak times, which are early in the morning and late in the evening, imported-energy prices are extremely high and have to be factored into the electricity tariffs. This problem is expected to intensify due to a projected 4 percent annual increase in energy demand. A major target of the Namibian mines, therefore, is to consider possible ways to address energy-saving challenges and to investigate possibilities for the mines to generate electricity internally during peak times. This is in alignment with the mines’ strategic plans and objectives to reduce total energy consumption and costs from both national and foreign electricity suppliers. In this paper, we explore addressing some of the key energy consumption and optimization challenges through process energy reuse and solar energy production to decrease demand for imported energy through a case study carried out in cooperation with Skorpion Zinc Mine and Refinery.

Jan 1, 2018