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By Albert E. Long

THIS GLOSSARY is published lay the Bureau of Mines as a contribution too the mining literature to fill a long-felt need for a compilation of the terms used by the diamond-drilling industry. The first step toward preparation of the glossary was taken in October 1955 when the Diamond Core Drill Manufacturers Association (DCDMA) proposed that the Bureau of Mines undertake the cons compilation and publication of a glossary of the terms used by the diamond-drilling industry. The work was authorized in July 1956, and a preliminary draft of the glossary was completed in may 1958. Copies of the draft were submitted for review to members of the DCDMA and appropriate personnel of the Bureau of Mines. The final draft, incorporating the many helpful suggestions of the reviewers representing both the diamond-drilling industry and the Bureau of Mines, was completed in March 1959.

Jan 1, 1960

By Charles W. Merrill

The U .S. Treasury stocks of silver have been reduced at such a rapid rate to meet industrial and coinage requirements that they face exhaustion in 3 or 4 years. Alleviation of the silver problem will require increasing supply or reducing demand. This paper examines possible long-range resource development and research programs and improved secondary recovery. The possible reduction or elimination of silver in coinage and development and introduction of substitutes in the arts and industry are also discussed.

Jan 1, 1965

By Charles W. Merrill

The U.S. Treasury stocks of silver have been reduced at such a rapid rate to meet industrial and coinage requirements that they face exhaustion in 3 or 4 years. Alleviation of the silver problem will require increasing supply or reducing demand. This paper examines possible long-range resource development and research programs and improved secondary recovery. The possible reduction or elimination of silver in coinage and development and introduction of substitutes in the arts and industry are also discussed.

Jan 1, 1965

By Miguel Tapia, Javier Alfaro, al et, Boris Alarcón, Sergio Giglio

El Proyecto Cachorro está ubicado a 150 Km al NE de la Ciudad de Antofagasta, en la Cordillera de la Costa de la Segunda Región de Chile, donde se encuentran depósitos de cobre tipo estratoligados, IOCG, y pórfidos (Mantos Blancos, 500 Mton @ 1,0% Cu; Antucoya, 1.200 Mton @ 0,3% Cu) (Fig. 1). El descubrimiento es el resultado de campañas de exploración greenfield en áreas cubiertas efectuadas desde 2013 por AMSA en el norte de Chile. El depósito se aloja en rocas estratificadas sedimentarias y volcánicas del Paleozoico superior al Jurásico inferior e intrusivos y brechas hidrotermales del Jurásico inferior que se relacionan temporalmente con la mineralización.

May 10, 2023

By Hudson S. B

With a particular electrode configuration, and a particular combination of electrode voltage and roll speed, a relatively small increase in electrode voltage, or a relatively small decrease in roll speed, resultsin a marked improvement in the separation of zircon from ilmenite. In general, fine minerals can be separated using a higher roll speed, or a lower electrode voltage, than is required to separate coarse minerals. The ionizing electrode should be reasonably close to the point at which mineral is fed on to the roll, and nearer to the roll than the non-ionizing electrode. The optimum conditions for the separation of zircon from ilmenite may not apply for the separation of other non-conductors from other conductors.INTRODUCTIONAlthough the high tension separators used in the Australian beach sand industry are efficient, this efficiency has been gained very largely by a process of trial and error, and not by a systematic study of the effects of changes in the operating variables. The optimum roll speed for a particular electrode position and electrode voltage, and the optimum electrode voltage for a particular roll speed and electrode position, can both be determined quite readily. It is not so simple to determine the optimum electrode position for a particular electrode voltage and roll speed. The reason for this is that the electrode used in high tension separators consists of two parts-an ionizing and a non-ionizing electrode respectively. The angular and radial positions of these electrodes, relative to the feed roll and to each other, affect the behaviour of conductors and non-conductors to varying degrees.

Jan 1, 1962

By Yuri Alberth Piñas Esteban

El siguiente trabajo técnico describe la importancia del uso de los detonadores no eléctricos de doble retardo y los cojines de agua como espaciador, en los taladros del techo y tajeos, puesto que su aplicación reduce el daño al macizo rocoso. El uso de estos detonadores no eléctricos de doble retardo minimiza la sobrerotura, crea labores más seguras y reduce las vibraciones en el macizo rocos, mientras que los cojines de agua son usados para disminuir la presión de detonación en el taladro, de forma que aminora el daño al macizo rocoso.

Sep 14, 2009

Since early July, domestic producer listings in primary aluminum ingot have been at 53¢ per pound. Dealers, however, lowered their August quotes by 1.8¢-2¢ to 47.5¢-48¢ per pound. BITUMINOUS COAL AND LIGNITE -The wildcat strike of UMWA coal miners which began on June 23 in protest of cutbacks in medical benefits appears to have ended. According to the West Virginia Coal Association on September 7, 1977, all mines in West Virginia were back in operation on September 6 and again on September 7. The Kentucky Coal Association reported approximately 2,500 miners were on strike in eastern Kentucky on September 6, but there was full employment on September 7.

Jan 1, 1977

By C. Sarkar

Increased competition in today’s global economy has put mineral industry under excessive pressure to effectively manage production assets to generate business wealth. Capital intensive industry (CII) organizations are seeking ways to manage skill resources, internal processes, and organizational networks with a view to reduce the cost of ownership of assets and increase efficiency of operations and service. The emerging concept of Enterprise Asset Management(EAM) is a collection of business processes that allow CII with right focus on return on investment on assets, to make right decisions on planning, acquisition, maintenance, operation, rehabilitation, and disposal of assets. Information technology (IT) can drive significant returns if the infrastructure covers seamlessly all business processes and all systems, like geographic information system, maintenance management, investment management, laboratory information management, and supervisory control and data acquisition system. The simple approach to IT in the past with disconnected silos of technology, information, and business processes cannot deliver the expected benefits under the modern business environment. Identification of business and application component is a prerequisite for the development of an asset management system that links effectively disciplined processes having characteristics of agility, speed, and integration. This paper discusses various issues and outlines the steps for developing an asset management roadmap in an organizsation. It also presents major business and application components of the system. Keywords: Enterprise asset management, Business architecture, Business component, Application component, Asset ownership, Asset operations, Information technology, Capital Intensive industry

Jan 1, 2003

By Jorge Olivari Ortega

El presente texto describe la relación de la expansión territorial del inca Cápac Yupanqui, último gobernante del Hurinsuyo con la explotación de los placeres auríferos en la zona de Huayllaripa (Apurímac). El gobierno del inca Cápac Yupanqui se caracterizó por el interés de la producción minera -en tanto estos minerales servían para ennoblecer el Coricancha, adoratorio construido especialmente para venerar al sol, dios tutelar de los incas. De otro lado, los mitimaes eran los migrantes que trabajaban la mina de oro a través del proceso de exploración, preparación y finalmente, de derribo del material aurífero. Para ello emplearon el método minero cochazo el cual consiste en almacenar grandes cantidades de agua (cocha) y precipitarla violentamente (lloclla), causando un fuerte derrumbe del material aurífero, que se depositará por gravedad en los canales de captación de las partículas de oro (toclla). Los placeres auríferos son la acumulación de fragmentos de piedras, arena, arcilla y de partículas de oro que provienen de la desintegración de vetas y mantos auríferos, y que por diversos agentes naturales como agua, nieve, viento y otros, han sido transportados, reunidos y concentrados en diferentes lugares.

Nov 1, 2015

A new series of reports called ?Mineral Perspectives" (MP's) has been initiated by the Bureau of Mines with the publication of MP-1 titled, "Far East and South Asia" by K.P. Wang and the staff of the Bureau of Mines. This new series parallels the creation of the recently announced "Minerals Commodity Profiles" (MCP?s). Both series are designed to provide current information on important sectors of the mineral economy to assist professionals in government, industry, and education in monitoring supply-demand relationships that have significant impact on our domestic economy as well as on the international scene. The orientation of the "Mineral Perspective" series is a geographic one which examines the mineral situation of a region or a country. The "Mineral Commodity Profile? series examines individual mineral commodities. They are in this sense complementary.

Jan 1, 1977

By Carlos G. C

Geological mapping in various parts of Australia is revealing a number of regional associations of mineralizations with particular persistent stratigraphic horizons. Such associations have been found in the Broken Hill district of New South Wales, in the Nairne district of South Australia, in the Mount Isa district of Queensland, and in the Cloncurry district of Queensland. The question has arisen as to whether such mineralizations are of sedimentary origin, syngenetic with the enclosing formation, or whether they are of epigenetic origin, and reflect the selective hydrothermal mineralization of favourable beds on a regional scale.The purpose of this investigation is to test the use of sulphur-selenium ratios as an objective method of distinguishing between suphide deposits or sedimentary or supergene origin, and sulphide deposits of hydrothermal origin, with particular application to the districts mentioned. At the same time much data has been accumulated as to the selenium content of Australian sulphide ores. The possible use of sulphur-selenium ratios for this purpose was first demonstrated by Goldschmidt and his coworkers (1933; 1935), and later by Carstens (1941). Goldschmidt and Strock (1935) found that pyrite of sedimentary origin had a sulphur : selenium ratio of the order of 200,000 or more, whereas pyrite of hydrothermal origin had a sulphur: selenium ratio of 10,000 to 20,000. Carstensfound that sedimentary pyrite deposits in Norway contained less than 1 g. Se per ton, whereas hydrothermal pyrite deposits contained 20 to 30 g. per ton.

Jan 1, 1954

By Robert M. Becker

This report (the second in a series of five) presents the mathematical development in extending the theory of sample reliability from a sample consisting of a fixed number of items to a sample consisting of a fixed amount of items. Examples of a fixed amount of items per sample are samples consisting of a fixed weight or a fixed volume of unequal size particles. The probability distribution functions (those here called the compound binomial and compound multinomial functions) are developed from fundamentals. Their distributions are generalized to include some measured characteristic of the items. Infinite population moments are derived from moment-generating functions, while finite population moments are developed from corresponding infinite population moments using the finite probability operator defined in part 1 of this series.

Jan 1, 1964

By Williams Morales

En el presente trabajo se encuentra una innovadora forma de almacenamiento de relaves en la industria minera, al aprovechar las sinergias de operaciones combinadas de lixiviación y planta Gold Mill. Se muestra el diseño, construcción, operación y los controles para dar estabilidad y solidez al almacenamiento de relaves en el pad La Quinua de Minera Yanacocha. Entre sus beneficios, destacan la reducción en los costos de construcción y protección del medio ambiente a través de la captación de agua directa hacia las plantas de EWTP.

Sep 20, 2019

By Douglas Rudenko

Most engineers, mine operators, or contractors acknowledge the importance of having accurate subsurface information in order to plan a project or solve a problem. Conventional methods of exploring the subsurface such as augering, core borings, or test pits can provide information, but it is often costly and sparse. Geophysical methods offer an alternative to help supplement sparse information~ gathered through conventional exploration techniques.

Jan 1, 1998

By Yun-Jie Wei

Seismic areas were in the eastern margin of the Qinghai-Tibet plain, whose structures were complicated, mainly composed of Maowen fault, Yingxiu fault and Pengxian-guanxian fault. The rapid rise of the Qinghai-Tibet plain led the crustal material of the eastern edge to move to the southeast along the faults on a large scale since the late Cenozoic; Minshan block structure and Long Men Mountain tectonic zone represented the strong nappe thrust movement as the east boundary of Chuanqing slip block; the stress was accumulating when squeezed, which to a certain extent resulted in breakdown of the crust, and earthquakes. The shock speed, high-energy accumulation, and the reversed dextrorotation of the earthquake fault characteristics et al. happened, which caused the development of secondary geological disastersts. According to on-site investigation, the typical geological disasters had thrust rock collapse, the instability deposit, the revival of potential debris flow et al. whose genetic model had been analysed.

May 1, 2009

By O. C. Garst

"The lightness and relatively high strength per unit weight of certain magnesium alloys have interested designing engineers for many years. Ever since the noted investigator Bunsen3/ first produced the element by electrolysis of the fused chloride in 1852, utilization of this light metal has been considered. Magnesium is widely distributed over the earth's surface in high-grade as well as low-grade deposits; it occupies eighth place in the list of elements arranged in order of their decreasing abundance, as there is 2.24 percent magnesium in the earth's lithosphere. Even though the element is distributed widely in the form of relatively insoluble: minerals and also as soluble salts in sea water and spring water, as well as being an indispensable constituent of plants and animals, the technology of magnesium was slow development. This slowness of development was first caused by confusion or the part of the early investigators who thought that magnesia, magnesite, magnetite, and the pyrolusite-type manganese ores were compounds of the same metal. At one time the metal that we now know as manganese was called magnesium, and magnesium was called either magnium or talcium. In addition to this coon, the chemical activity of the metal, especially at high temperatures, created problems that are still difficult to solve.With the advance of science in all branches, .methods for -he production of magnesium were developed. The methods first used for producing the element were: (1) reduction of magnesium salts with alkali metals,4/ (2) electrolysis of aqueous solutions of magnesium salts, and (3) electrolysis of fused magnesiun salts.The first attempts to produce magnesium by the carbothermal reduction of magnesia were failures as sufficient thermodynamic knowledge concerning the reversibility of the reaction between magnesia and carbon was not at hand. As the igneous electrolytic Method for making the element was more easily controlled than the others and. yielded more metal per unit of energy, considerable work was expended on the improvement of this process. The work in this field paralled that on the electroreduction of aluminum and the alkali metals. For several years the entire magnesium industry was dependent on this igneous electrolysis process for its supply of the metal, but as demand for the metal increased and more scientific knowledge was available, other processes were developed. Today magnesium is produced by the electrolysis of molton magnesium chloride electrolytes, the carbothermal reduction of magnesia, in arc furnaces followed by shock cooling of the furnace gases by a coin inert atmosphere, and the silicothermal reduction of calcined dolomite in stainless steel retorts."

Mar 1, 1946

Geophysical Abstracts 1 - 86 wore issued in mimeographed form by the Bureau of Mines; Abstracts 87 - 111 were published in bulletins of the Geological Survey; Abstracts 112 - 119 were issued in mimeographed form by the Bureau of Mines as Information it ion Circulars 7256, 7257, 7267, 7273, 7285, 7292, 7303, and 7310. 1. GRAVITATIONAL METHODS 7786. Barton, D. C.3/ Case Histories and Quantitative Calculations in Gravimotric Prospecting. Am. Inst. Min. and Meat. Eng., New York, Tech. Pub. 1760, 1944, 49 pp.

Jan 1, 1945

By Maurice Hunter

The paper outlines recent design developments in the computerization of surface crawler drills for the quarry industry. It references the technology firstly developed for the underground mining and construction industry, where automation and computerization has been in demand for a number of years.

Jan 1, 2003

By Rob Morrison, Peter Cameron

"Many products and technologies have been developed from outcomes of research projects carried out by the Julius Kruttschnitt Mineral Research Centre (JKMRC). When these products and technologies are applied to the design and optimisation of blasting, comminution and separation, improvements in profitability can be realised.In 1970 Alban Lynch promoted two practical ideas to improve plant operations:• Ore and equipment properties can be separated allowing experience with one type of ore or equipment to be transferred to other types of ore and equipment. If this experience was encapsulated in a mathematical model, then these properties could be combined and used to simulate (ie. to design and to optimise) complete mineral processing circuits.• Many problems associated with scale-up from laboratory to industrial equipment could be eliminated by experimental work on full-scale equipment in the plant.Many JKMRC research projects have focussed on the development of models of unit operations in mineral processing and their application to process simulation.Models of comminution and classification developed at the JKMRC have been used since the early 1980's. Ore characterisation techniques developed to support these models are licensed world wide through JKTech. The application of comminution modelling techniques to blasting, which optimises the process feed size distribution is used in Mine-to-Mill® projects. The advances in the understanding and modelling of froth flotation over recent years have provided the opportunity for integrated ore characterisation and process optimisation from resource to product.JKMRC project outcomes often provide proven opportunities for the mineral industry to improve performance and productivity. JKTech was established in 1986 to commercialise and market the most promising outcomes and thus ensure their continuing availability to the mineral industry.They include:• Commercial software (JKSimMet, JKSimBlast and JKMetAccount).• Monographs (Comminution and Blasting).• Technologies (Mine-to-Mill® and flotation optimisation).• Hardware products (JKFrothCam, JKJetLift® and the Mineral Liberation Analyser).This paper summarises these technologies and their benefits."

Jan 1, 2003

By Kash Sirinanda

¿Cómo dirigir nuestra agenda hacia la creación de una organización minera sostenible? En el presente texto se examina la compleja estructura de las empresas mineras, y se abordan los cambios en cuanto a la creación de valor minero, tanto como las tendencias futuras en la industria. Tomando en consideración la sostenibilidad propuesta por las Naciones Unidas para los modelos de negocio en minería, el autor explora las áreas en las que debería centrarse el liderazgo minero del futuro.

Oct 30, 2020