Search Documents

By Gordon T. Austin

The combined value of production of natural abrasives, which includes tripoli, special silica stone, garnet, staurolite, and emery, increased about 21070 in 1989. The increase in the value of staurolite and tripoli production was the result of an increase in the quantity of materials produced and an increase in the unit value. Emery decreased due to the significant decline in the volume of the material produced. Special silica stone experienced both a decrease in unit value and quantity produced. Garnet showed a small increase in quantity, but a decrease in unit value. The silicon carbide industry saw a slight decrease in the quantity produced and a 12070 increase in the value of production. The fused aluminum oxide industry showed a 5070 decline in the quantity produced, but enjoyed a 15070 increase in the value of production. Combined production for both industries decreased 4070 in quantity but increased 13070 in value compared with those of 1988.

Jan 1, 1991

New York State Museum, Albany, N. Y. D H. Newland, State Geologist. A complete list of publications or the latest lists of available publications will be sent upon application. A series of Bulletins on The Mining and Quarry Industry of New York are available as follows: Bulletin 51 (1910), 15 cents; 161 (1911), 20 cents; 166 (1912), 20 cents, 174 (1913), 20 cents; 190 (1915), 15 cents; 277 (1925-26), 50 cents; 295 (1927-1929), 40 cents. Another series discusses the Geology of the State by Quad¬rangles, available as follows: Bulletin 153, Broadalbin Quad (1911), 25 cents; 154, Sche¬nectady Quad. (1911), 20 cents, 170, North Creek Quad . (1914)

Jan 1, 1933

By Henry Kreisinger, F. K. Ovrrz, C. E. Augustine

The Bureau of Mines is conducting investigations to determine how fuels belonging to or for the use of the United States Govern- ment can be utilized with greater efficiency. As a result of these investigations a number of reports have been published, each report treating of one phase of fuel utilization. A list of these publications is given at the end of this bulletin. The efficient utilization of coal depends on the correct design of furnaces and on their proper operation. To attain both of these conditions a knowledge of the fundamental principles of combus- tion is necessary. Therefore, the study of the combustion of coal in industrial furnaces has been made a part of the bureau's fuel in- vestigations. The desirability of investigating the fundamental principles of combustion was suggested by the study of a large number of steam- ing tests made by the fuel-testing division on coals from all of the more important fields in the United States. The results of these tests have been published in Bulletin 325 of the United States Geological Survey and in Bulletin 23 of the Bureau of Mines. As a result of that study a plan to investigate the combustion of coal in a special apparatus in which all conditions could be controlled was presented to the National Advisory Board for Fuels and Struc- tural Materials at its meeting of April 10 and 11, 1906. The plan received the approval of the board, and since the establishment of the experiment station of the Bureau of Mines at Pittsburgh the investigation of the combustion of coal has been carried on intermit- tently. The history of these investigations is given in Technical Paper 63.

Jan 1, 1917

By Jorge Olivari Ortega

"Los incas desarrollaron un censo que les permitía planificar el desarrollo socio-económico de la región, como la actividad minera aurífera. En ese sentido, el gobierno del inca Mayta Cápac elaboró un sistema estadístico, a partir de los quipus para registrar toda la información y obtener el máximo provecho de los recursos existentes. Por ello, el presente texto describe el proceso del método estadítico que permitió a los incas adquiirir el tributo que habían programado. Para ello, se utilizaron los cordones de variados colores (quipus) para diferenciarlos en cada actividad como el amarillo que significaba la actividad minera aurífera. En estos cordones, los quipucamayoc registraban la cantidad de oro producido durante la mita minera o con los mitimaes en los yacimientos auríferos el número de personas que participó, la cantidad de días, las herramientas, los viveres, los vestidos, etc. Las herramientas utilizadas en la explotación de los yacimientos auríferos tipo lavadero, son las mismas que en la actividad agrícola, ya que en ambas se requieren remover la tierra: en la agricultura para sembrar las semillas, y en la minería aurífera, para lavarla y obtener las partículas de oro."

May 1, 2016

By J. A. Botín

In modern mining, the core of mine planning and design is the block model, a simplified representation wherein the ore deposit is divided in a number of virtual rock cubes, each characterized by technical and economics parameters. Mining engineers use this model to design the mine and develop production schedules. Traditionally, sustainability issues are not considered in the mine design, planning and engineering processes but rather are incorporated in the later stages of the feasibility evaluation as necessary expenditures and operating costs. This paper describes the results of a research project aiming to develop a methodology to incorporate sustainability parameters directly into the block model, so that they become an integral part of the design, planning and scheduling processes. It is considered that the incorporation of sustainable parameters into the block model would yield a more responsible mine design and improve mining projects sustainability performance

Feb 27, 2013

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 Hernán Arévalo

El presente texto describe las perspectivas en la utilización de la tecnología de conversión del carbón en los países latinoamericanos para producir petróleo sintético y derivados. En ese sentido, el proceso de gasificación carbón y síntesis en combustibles líquidos es costoso. Por ello, se requiere un análisis económico cuidadoso antes de decidir la instalación de cada planta en los países en América Latina y en el que los institutos geológicos y del carbón de los países de Latinoamerica inicien o continuen, según sea el caso, con la exploración de los recursos carboníferos para determinar reservas, incluyendo las de los carbones hidrocarburables.

Mar 1, 1982

By S. Tumionen

El sistema de análisis ha estado en operación en cinco de las plantas concentradoras de la compañía por un tiempo suficientemente largo para realizar un análisis adecuado de los beneficios logrados en el control de los procesos de concentración. En ese sentido, el presente texto describe el analizador en flujo Courier 300 y su experiencia en plantas concentradoras. El primer sistema analizador fue instalado en la mina de Pyhasalmi a fines de 1967 y se divide cuatro grupos funcionales: equipo o sistema de muestre, analizador, equipo de salida y equipo auxiliar. Posteriormente se instalaron cinco sistemas analizadores Courier ( Kereti, Pyhasalmi, Vihanti, Vuonos, Kotalahti), donde se lograron mejoras considerables en el control y economía de las plantas concentradoras. Por ello, el conocimiento inmediato de los cambios en el proceso y la posibilidad de corrección rápida han permitido obtener una producción más uniforme y mayor capacidad de recuperación.

May 1, 1975

By P. Tumialán

El presente trabajo señala la modalidad del empleo en la exploración de las estructuras mineralizadas en diversos yacimientos métalicos a través del estudio de las curvas de sus leyes, curvas estructurales, de potencia y las de cocientes metálicos. Es decir, en este tipo de estructuras se puede estudiar un tipo de las curvas señaladas anteriormente. Asimismo, la mejora del análisis de este tipo de curvas depende de la relación con la petrografía de las cajas, tipos de alteración hipógena, supérgene, rumbo y buceamiento de las mismas, minerales opacos, y ganga de la estructura mineralizada, fracturas y fallas de premineralización y de posmineralización.

Nov 20, 1972

By O. C. Blade

This report on the properties of aviation gasolines and aviation jet fuels produced in the United States during 1956 was made under a cooperative agreement between the American Petroleum Institute and the Bureau of Mines of the United States Department of the Interior. Analytical data are presented for 120 samples of aviation gasoline and for 38 samples of aviation jet fuel. The analyses were made on samples typical of the manufacturers' 1956 production in their laboratories and the results submitted to the Bureau of Mines for compilation. The products of 20 manufacturers of aviation gasolines and of 17 producers of aviation jet fuels are represented.

Jan 1, 1957

By Gladys Calenzani, Alexandra Almenara, Graciela Arrieta

Según estadísticas del Minem, la participación de la mujer en la industria minera peruana llega a solo un 5.4% del empleo total en minería. De este porcentaje, casi la mitad corresponde a un cargo administrativo y solo un 4%, a un cargo de toma de decisiones. La presente investigación busca mostrar el diagnóstico inicial de participación de la mujer en la minería del Perú, estudiar el caso de Chile —país de la región cuya actividad principal también es la minería y que a la fecha tiene un 8.5% de participación de la mujer en la industria—, recoger aquellas buenas prácticas que podrían ser aplicables en el país y establecer los principales retos y propuestas innovadoras para la mediana y gran minería.

Sep 20, 2019

By Peter A. Rona

The recent discovery of the first black smoker-type hydrothermal venting and massive sulfide mineral deposits at a site in the rift valley of the slow-spreading Mid-Atlantic Ridge near latitude 26°N, longitude 45°W (Rona et al., 1986, Nature, 321: 33-37), demonstrates that a complete series of hydrothermal mineral deposit types exists at slow-spreading oceanic ridges (half-rate = 2 cm/y), similar to the series previously known at faster-spreading oceanic ridges (half-rate > 2 cm/y). The largest hydrothermal mineral deposit known at a seafloor spreading center is a stratiform massive sulfide body with bulk dry weight of about 100 x 106 metric tons in the Atlantis II Deep at the slow-spreading axis of the Red Sea. This observation invalidates the concept that size of a hydrothermal deposit is directly proportional to rate of seafloor spreading. Instead, the occurrence, grade and size of a hydrothermal deposit formed at a seafloor spreading center is controlled by anomalous chemical and physical conditions which may occur at extremely localized sites at the full range of spreading rates. The basic hydrothermal process involving subseafloor hydrothermal convection driven by magmatic heat sources appears to be similar at slow- and faster-spreading centers. However, differences exist in the periodicity of magmatic cycles that energize hydrothermal circulation (104 y at slow-spreading centers; 103 y at faster-spreading centers); in the distribution of hydrothermal sites along a spreading axis (estimated 100 km along slow-spreading centers; 10 km along faster-spreading centers); and in residence time

Jan 1, 1986

By S Paciornik

Computer-controlled microscopes with digital image acquisition and analysis led to the creation of the new field of digital microscopy. These techniques not only allow a certain degree of automation but have also brought new possibilities to microstructural characterisation. One of these new and promising possibilities is co-site microscopy, which links different kinds of information obtained from different microscopy techniques. The present work presents the development and implementation of a co-site microscopy methodology that combines images obtained by reflected light microscopy (RLM) and scanning electron microscopy (SEM). This methodology can improve the SEM analytical capacity by adding colour information from RLM. It involves the whole sequence, from image acquisition at the microscopes to the analysis of the phases using pattern recognition techniques. An automatic registration procedure for the two kinds of images was developed, allowing the adjustment of magnification, translation, rotation and pixel size, and the correction of local distortions. Thus, the images from RLM and SEM can be combined to build a multidimensional data set of each field, which can then be used in a pattern recognition approach to discriminate different phases. The methodology was tested with a copper ore sample, aiming at the discrimination of minerals that are not distinguishable with either RLM or SEM.

Jan 1, 2008

This paper discusses the social and economic impact of mining, and in particular goldmining, on New Zealand. The range of topics covered and their complexity has confined us in this paper to highlighting the main points of concern û a detailed report is under preparation. A major problem in undertaking this study was the lack of hard data on important environmental, economic and social issues and if there is to be effective planning in the area of natural resource use this situation must be rectified. The following conclusions were drawn: Goldmining was very important in shaping New Zealand's early social and economic development, providing wealth, employment and impetus for social change.Foreign investment and technology has been an essential element in New ZealandÆs economic development.Mining is a small industry at present by this must not be allowed to obscure its potential to broaden New Zealand's economic base and provide foreign exchange.With modern methods, development of mineral resources and environmental protection are not incompatible but certain unique and irreplaceable areas must be preserved.There are problems in evaluating mining and other projects because different groups hold different values, and arguments often hinge on the valuation of costs and benefits rather than the technical aspects of the analysis.Mineral exploration is a high risk business and the potential returns must be sufficient to attract capital if New Zealand's mineral resources are to be developed.A resurgence of goldmining will clearly have obvious benefits for Waihi but the local community must plan carefully for their future. New Zealand will also gain valuable foreign exchange required for higher levels of economic activity.

Jan 1, 1981

By Dave Kay, Young-Suk Song

To meet the needs of South Korea's rapidly expanding economy, a large number of infrastructure projects are under way to improve transportation efficiency within the nation. These projects include high-speed rail links between major population centres and improvements to the road network. Being densely populated and geographically mountainous, infrastructure development in Korea requires a significant amount of tunnelling. Owing to the predominantly hard granitic nature of rock, drill and blast is the preferred method of tunnel advance. The Korean tunneller, however, faces the same pressures as those of his international counterpart in that both cost and production targets need to be achieved while meeting expectations of both community and regulator.

Jan 1, 2005

By Gordon T. Austin

The combined value of production of natural abrasives, which include tripoli, special silica stone, garnet, staurolite, and emery, increased about 4% in 1990. The increase in the value of tripoli production was the result of an increase in the unit value. Emery increased owing to an in? crease in the volume of the material produced and an increase in the unit value. Special silica stone experienced a decrease in unit value and an increase in the quantity produced. Garnet showed a 10% in? crease in quantity and a 73% increase in unit value. Staurolite decreased about 8% in the quantity produced, and the value of production decreased about 10%. The fused aluminum oxide industry showed a 5% decline in the quantity produced and in the value of production. The silicon carbide industry saw a 10% decrease in the quantity produced and a 9% decrease in the value of production. Production for both industries decreased 7% in quantity and value compared with those of 1989.

Jan 1, 1993

By Jorge Medina

"El presente trabajo señala el proceso de recuperación de puentes y pilares en la mina Cobriza a través de un estudio sobre las propiedades geomecánicas del macizo rocoso, el cual debe ser aprovechado no sólo para mejorar la estabilidad de la mina, sino para lograr una recuperación económica de puentes y pilares. En este sentido, la recuperación de puentes y pilares es técnica y económicamente factible, y puede ser realizada conun aceptable grado de seguridad minera. Sin embargo, no ocurre lo mismo en las áreas que fueron rellenadas con material detrítico. Asimismo, el diseño de la recuperación de los pilares que sustentan a los zig zags deberá preveer la conservación y mantenimiento de la infraestructura actual y la secuencia de avance en la recuperación y diseños detallados de cada zona por ser explotada. Todo ello en base a un inventario completo tanto de reservas minables como de labores mineras."

Sep 22, 1997

By Pablo Herrera

Para el cuidado de los equipos móviles, se requiere de un plan matriz de monitoreo de condiciones, donde se defina un estrategia que optimize el sistema en equipos móviles de gran equipaje. En este sentido, el presente texto señala cómo el mantenimiento predictivo se puede incorporar dentro del ciclo de mantenimiento general a través de resultados que afectan directamente el negocio como el aumento de la disponibilidad de activos físicos de la industria.

Jun 1, 2014

By Enrique Zápata

"El presente trabajo describe la influencia de los nuevos métodos y herramientas en la ocurrencia de accidentes incapacitantes que se han registrado durante los últimos años en Milpo. Para ello, se considera las condiciones de terreno y la profundización de la mina, las estadísticas de accidentes capacitantes, la comparación de métodos y resultados, la síntesis comparativa de costo por método, las herramientas nuevas (raise borer, sistema de descarga), tecnología y la exposición al riesgo de accidentes, y la frecuencia lógica de ocurrencia de accidentes. En este sentido, el diseño de nuevas herramientas otorga a los operadores una ubicación panorámica y segura,comodidad y control de un panel de fácil manejo, reduciendo la frecuencia de la frecuencia de ocurrencia de accidentes incapacitantes y fatales."

Oct 6, 1999