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By AIME AIME

ARRANGEMENTS for the Annual Meeting of the Institute were well advanced at the end of December as the following program will show. Heretofore this has been printed separately, but its inclusion in the Annual Review issue of MINING AND METALLURGY will, it is hoped, make it more easily available for reference until the final program is issued, which will be distributed at the meeting. Added details will appear in the February issue. Last year's meeting drew a record crowd of over 2300 which should be exceeded this year. Early reservations at the headquarters hotel, the Waldorf-Astoria, or any other convenient hotel are desirable, as are prompt reservations for the Annual Dinner. No one need worry about too much speechmaking this year, for the honors will be awarded and accepted in a few words instead of a few paragraphs, in seconds rather than minutes.

Jan 1, 1939

By D. Pohl

The past decade has seen rapid expansion in the West African mineral exploration environment. This expansion has been largely driven by changes in ?Political climate ?Fiscal and legal regimes ?Exploration approaches ?West African geology. Major regional mapping and geochemical surveys by the UNDP, and the BRGM in the late 1970s and early 1980s laid the foundation for the rapid development of mineral exploration and resources during the past decade. An additional driving impetus was the discovery by native artisanal miners of many significant new gold occurrences at Libiri, Essakan, Bouda and Tirahori, during the great droughts of the late seventies and early eighties.

Jan 1, 1998

By Larry Mirabelli, David Lilly

In 1777, the French naturalist, Georges Louis Leclerc, Compte de Buffon developed a statistical technique to estimate the width between two parallel lines by randomly throwing a needle at the two lines and counting the number of times the needle intersected one of the two lines. By knowing the length of the needle, the distance between the parallel lines could be estimated. This analysis was named the “Buffon’s Needle Problem”.

Jan 1, 2008

By D. H. Platt

Gypsum and gypsite, used in the manufacture of plaster and plaster products, have been mined from deposits near Acme, Hardeman County, Tex., for more than 30 years. The Certain-toed Products Corp., 120 East Lancaster St., Ardmore, Pa., operates the Acme, Tex., mine. Underground hauling was done with storage-battery and Diesel-electric-powered shuttle cars. Many mining companies and individuals have manifested interest in all types of equipment powered by Diesel or Diesel-electric units, as attested by the recent increase in use of Diesel-powered equipment in underground metal and nonmetal mines. The purpose of this paper is to describe the manner in which a storage battery-powered Joy Model 60D2 shuttle car was converted to Diesel-electric power. The conversion was made, at the instance of the operating company, by Stewart & Stevens on Services, 4801 Lemon Ave., Dallas, Tex. This is believed to be the only such converted shuttle car in use.

Jan 1, 1950

By Alfred Bodenlos

El presente texto señala los depósitos de zinc y plomos encontrados en los cateos del flanco noroeste del cerro Huancapetí, perteneciente a la Cordillera Negra. En el flanco noroccidental del cerro Huancapetí, hay varias vetas que han sido exploradas por pequeños cateos, cuyas altitudes van desde 4480 hasta 4670 metros. Para llegar a esas vetas solo hay caminos malos que cruzan la cumbre de la cordillera al sur del área de la mina Huancapetí. De otro lado, en 1947 la única mina en actividad era la de Wilson, alcanzando 10 toneladas de concentrados al mes escogidos a mano, así como la mina San Idelfonso, la Improvisada, Mariscal y los cateos Señor de la Soledad y Fernandiita.

Nov 1, 1957

By S. H. Lorain

This paper, which describes lode gold mining in Idaho county, Idaho, is one of a series on western mining districts being published by the Bureau of Mines. It describes mining and milling practices, gives costs, and discusses transportation, climate, power, labor, and other conditions that affect them. The materiel upon which the paper was based was gathered during a field survey in the summer of 1937.

Jan 1, 1938

By Kenneth M. Maas

The Bureau of Mines inventoried the land in southwestern Alaska to classify ownership and availability and compared this land with known mineral terranes and mineral deposits. This report discusses and quantifies the potential for favorable location of mining claims for metalliferous (locatable) mineral deposits. Of the nearly 24 million acres that constitute the study area, approximately 3.6 million acres or 17% are available for mineral location, 3.4 million acres or 14% are available with restrictions, and 17 million acres or 71% are unavailable. Mineral terranes are known to underlie about 7.8 million acres or 33% of the study area; 3 million acres or 38% occur on land available for mineral location, 1.3 million acres or 17% occur on land available with restrictions, and 3.5 million acres or 45% occur on unavailable land. The State of Alaska has opened over 91 % of its land in the study area to mineral location; in comparison, the Federal Government allows mineral location on 0.07% of the land under its jurisdiction. There are 117 known mineral deposits or occurrences within the study area, including 77 lode deposits and 40 placer deposits. Of the 41 lode deposits occurring within a mineral terrane, 2 occur on available land.

Jan 1, 1988

By Verônica Scarpini Candido

O alto consumo de energia e a elevada emissão de dióxido de carbono são os maiores problemas da indústria de cimento Portland relacionados à poluição do meio ambiente. Com o objetivo de reduzir estes problemas, os cimentos geopoliméricos despontam como uma nova classe de materiais de alto desempenho e não agressivos ao meio ambiente utilizados como aglomerante mineral capaz de substituir total ou parcialmente o cimento Portland. Estes cimentos são considerados quasi-frágeis devido ao seu comportamento elástico não-linear, provocado pela relaxação e redistribuição de tensões antes da ruptura. Todos os resultados obtidos no programa experimental para o concreto de cimento geopolimérico (CCG) foram comparados com aqueles obtidos para o concreto de cimento Portland (CCP), sob as mesmas condições de ensaio. Neste trabalho, são apresentados resultados de difração de raios-X (DRX), microscopia eletrônica de varredura (MEV) e análise térmica (DSC/TGA), a fim de reunir informações para um melhor entendimento da microestrutura do concreto geopolimérico.

Oct 30, 2017

By Iván Salas, Abdhiel Bustamante

Se efectúan análisis de correlación con base en los índices de diversidad de áreas revegetadas dentro de los procesos de cierre progresivo en la Unidad Minera Constancia, en la provincia de Chumbivilcas, región Cusco. Estos índices fueron correlacionados con los valores de cobertura vegetal e Índice Normalizado de Vegetación (NDVI), el primero es el valor considerado dentro de los compromisos asumidos en los procesos de cierre.

Sep 29, 2023

By R. J. Brison, W. C. Bleimeister

The International Salt Company has long been interested in finding an efficient process for the removal of impurities from rock salt, and particularly from the rock salt produced at the Detroit mine. Methods which have been used previously at the Detroit mine included both hand sorting and differential crushing in a Bradford breaker with rejection of the oversize. Neither of these methods was adequately effective. The development of a new process for removal of impurities from rock salt has been described in the preceding article." Basically, the process consists of exposure of crude rock salt to radiant heating which selectively heats the impure particles. Subsequently the heated particles are removed by adhesion to a heat sensitive-coating on a conveyor belt. This method was found to be effective in improving both the quality and appearance of rock salt by the rejection of the dark, impure particles. The first commercial unit employing the new thermoadhesive method of dry separation of minerals was installed at the Detroit mine of International Salt Company in Detroit, Mich. (Fig. l). This unit was first put into operation in March 1957. The purpose of the Detroit installation was 1) to serve as a pilot plant for evaluating the process on a commercial scale and 2) to produce marketable quantities of rock salt of improved quality and ap- pearance. The design of this plant was based on the results and information obtained from a 1-tph pilot plant at Battelle Memorial Institute. DESCRIPTION OF PLANT Location: The separation plant was installed underground near the crushing and screening plant, for this was the most suitable location from the standpoint of material handling. Furthermore, ample space was availabe at this location. Because the process requires a relatively constant temperature, the uniform year-around temperature of the mine (57°F) gave an added advantage to an underground operation. Feeding: The rock salt is conveyed to a surge bin, from which it is fed to the heating unit by a conveyor. The feed-rate control consists simply of an adjustable gate at the bottom of the surge bin. The plant may be fed either No. 1 grade of rock salt (0.279 to 0.375 in.) or No. 2 grade (0.375 to 0.500 in.) with a maximum input capacity of 500 tons per 15-hour day. Heating Unit: The heating unit (Fig. 2) consists of a panel of infrared lamps suspended inside a low-speed revolving screen. The radiant-heat panel, which is curved for most effective utilization of the heat, holds 240 infrared lamps of standard industrial type, each rated at 500 watts. The position of the panel is adjustable so that it can be placed centrally over and to within 6 in. of the salt bed on the screen. The entire heat panel is suspended by rollers in ¦ R. J. Brison and O. F. Tangel: Development of a Thermo-adhesive Method for Dry Separation of Minerals.

Jan 1, 1961

By Luis Noval Noval García

El objetivo de la ventilación es desarrollar una atmósfera saludable, segura y apta para la realización del trabajo por parte del personal. En ese sentido, el presente texto señala los gases como problemas comunes presentados dentro del ambiente minero tales como asfixia por anoxia (caso de inhalación) intoxicación, envenenamiento y muerte (letal) e inflamación y explosión (Productos). Para eliminar estos riesgos se debe eliminar las causas a través de una buena ventilación. Asimismo, es necesario conocer las propiedades de los gases, disponer de equipos para detectar su presencia y procurar los medios para eliminarlos.

Sep 1, 1984

By Abel Gastañaga Coll

El carbón es una sustancia fósil de origen vegetal, color negro y estado físico sólido que se encuentra en la corteza terrestre interestratificada entre rocas sedimentarias, de donde es extraída mediante técnicas de minado para su utilización principalmente como combustible, reductor y materia prima para la obtención de productos carboquímicos. Sin embargo, la energía solar "enterrada" deriva del proceso de la fotosíntesis, donde los vegetales del carbón, pueden sintetizar su propio alimento a partir de sustancias símples tales como el agua y el dióxido de carbono que son captadas del suelo y del aire, para transformarla en azúcar, que es una sustancia alimenticia constituida por un hidrato de carbono. En este sentido, el presente texto señala el uso del carbón como energía solar enterrada en el que se busca la generación de electricidad, la licuefacción y gasificación del carbón futuro para compensar el déficit de la disponibilidad del petróleo y el resurgimiento de la carboquímica. En cambio, los incrementos del empleo del carbón en la industria siderúrgica, continuarán con el actual ritmo moderado.

May 1, 1981

By Sheldon Wimpfen

La exploración es una actividad que utiliza la prospección geológica, prospección geofísica, sondajes, pozos de exploración o de sondeo, galerías de avance subterráneas, de superficie y socavone. Las etapas de la exploración se desarrollan en cuatro etapas : l evaluación regional, reconocimiento de áreas favorables, evaluación de superficie detallada de las áreas de objetivo. Asimismo, se describe la nueva técnicas de exploración y sus incentivos.

Mar 1, 1980

By J. Adkins

This document presents a description of the results of a project aimed at producing a broad description of current mining training programs and an evaluation of their effectiveness with respect to reducing mine injuries. Aggregate training and injury data were used to evaluate the overall training effort at 300 mines as well as specific efforts in twelve categories of training course objectives. From such evaluations, recommendations were derived with particular emphasis being placed on identifying program characteristics that tend to be associated with effective training. Recommendations were also formulated with reference to role changes in industry and government interaction with respect to training programs, new or additional training programs, changes in the types of course materials and training methodologies, and recommendations concerning new areas for investigation.

Jan 1, 1976

By Stratton-Crawley R., G. E. Agar

"A study has been done of the scale-up of laboratory bench-scale flotation to continuous plant circuit performance. It was found that the impellor speed and the air flow rate influenced the results and in this case extreme values of these operating variables were required in order to reproduce the plant rougher results in the laboratory. Despite the experimental uncertainty introduced by these extreme values, it was demonstrated that the plant performance could be predicted and experimentally reproduced with bench-scale tests.IntroductionThe mineral processing industry relies heavily on batch flotation testwork to design flowsheets, evaluate reagent s and compare various types of ore. The batch tests are generally regarded as being directly comparable within themselves, but quite often they relate poorly or not at all to continuous circuits. Obviously this dilemma generates considerable uncertainty with wide-ranging ramifications. One of the manifestations of this unfortunate situation is the commonly expressed opinion that ""it may work that way in the laboratory, but it will never work that way in the plant"".In a previous publication, a method was described whereby the results of batch bench-scale tests could be used to simulate a locked cycle flotation test series. The work to be described here is a continuation of that investigation with an extension to the simulation of an actual plant circuit. It would have been preferable to progress from laboratory batch data to a continuous pilot plant and then finally to a full-scale plant operation. However, because that possibility did not present itself, an attempt will be made to show that the performance of an existing plant circuit can be successfully simulated from batch data. The success of the procedure can be judged by the agreement among the plant results, a locked cycle test and the predicted results based on batch tests."

Jan 1, 1982

By Rafael Abreu Fraga

Este trabalho tem como objetivo apresentar a nova linha de Laminação de Chapas Grossas da Usina de Ouro Branco da Gerdau, marcando a entrada da empresa na produção de chapas grossas de alto valor agregado no Brasil. A primeira fase do projeto consiste de um forno de reaquecimento de placas, um laminador de chapas grossas, sistema de resfriamento acelerado – Mulpic®, desempandeiras a quente e a frio e uma completa linha de acabamento constituída de linha de tesouras, oxi corte e máquina de ultra som. Neste projeto estão empregadas as mais modernas tecnologias para garantir a qualidade do produto: automação completa dos equipamentos com modelos matemáticos de controle do processo, sistema HAGC, Work Roll Bending e Work Roll Shiftting Smart Crown®. A nova linha tem capacidade de produção de 1,2 milhões de toneladas por ano na primeira fase, podendo alcançar 1,8 milhões de toneladas na segunda fase com espessura variando entre 6,0 a 150 mm e largura entre 900 a 3700 mm.

Aug 17, 2017

By Peter Amelunxen, Javier del Río, Marcial Medina

Este documento técnico describe las iniciativas de mejora y nuevas tecnologías implementadas en la planta concentradora de la mina Constancia, que permitieron incrementar en forma sostenida los principales indicadores de producción: troughput, recuperación, disponibilidad y utilización. Constancia es un yacimiento de pórfidos de cobre-molibdeno que incluye mineralización tipo skarn, ubicado a 4,100 msnm en los Andes sur-este del Perú, región Cusco.

Jul 30, 2020

By Tad Crowie, Victor Delgado, Nick Katsikaros, Tim Hughes

"A number of silver producers have identified a need for a system to recover silver and gold from base metal flotation concentrates on site rather than sending the concentrate to third party smelters to improve mine economics. Historically intensive cyanidation has only been used for coarse gold gravity concentrates in batch machines but Gekko have applied the InLine Leach Reactor (ILR) to these difficult to leach concentrates.The ILR’s unique ability to operate at various solid to solution ratios, high mass capacity, the ability to handle fines, the use of peroxide to aid silver leach kinetics and simple operation has resulted in significant economic benefits to Hochschild PLC’s Selene and Arcata operations. This paper describes the commissioning phase of the ILR5000BA intensive cyanidation reactors on concentrates from the Selene mine at the Ares Concentrator.INTRODUCTIONIntensive leaching of high grade concentrates in gold ore treatment is now commonplace and is considered an essential feature of most gold circuits (Lane, Fountain and LeBrooy, 2008). The devices commonly used for intensive leaching (InLine Leach Reactor, Acacia Reactor, etc) are specifically designed for the typical coarse nature of the concentrate.In some of these intensive leach applications, significant amounts of silver are co-recovered with the gold. In fact, the intensive leaching conditions of 1 to 2% NaCN in solution and high dissolved oxygen levels, overcome the issue with silver’s slow dissolution rate in traditional CIL/CIP circuits and avoids the formation of insoluble silver sulphide minerals on the surface of the gold (Marsden, 2006).There are a significant number of mine operators producing silver in the form of mixed base metal sulphides flotation concentrates. Typically the mine operators are paid for the silver after processing of the concentrate by the base metal smelter whom recovers the silver during the refining process."

Jan 1, 2010

By James Westfield

A brief résumé follows of some of the most recent activities of the Division of Coal-Mine Inspection that have had a favorable effect. on health, safety, and injuries at coal mines: 1. There were approximately 8,510 active coal mines in the United States during 1955. In all, 82,389 regular Federal inspections of coal mines have been made since Public Law 49 became effective in May 1941; 9,823 of these inspections were made during 1955. 2. The Bureau of Mines introduced the revised Coal-Mine Accident-Prevention Course for Supervisors in the coal-mining industry on March 1, 1948. Since that date, 19,455 supervisors and those aspiring to official positions have completed such training conducted by personnel of the Division of Coal-Mine Inspection.

Jan 1, 1956

By IPMI Educational and Scientific Foundation

It is with great pleasure that we announce the availability of this fourth issue of the IPMI Journal, a publication of the International Precious Metals Educational and Scientific Foundation. This digital peer reviewed publication has been created as a vehicle for the sharing of technical information related to the science and technology of precious metals. Since 1976, the International Precious Metals Institute has championed the exchange of information of critical importance to the precious metals scientific and commercial communities through its various communications vehicles. This has included instructional videos, annual conference symposia, special topic committee meetings, regional seminars, and professional and student achievement awards. Due to the breadth of important topics related to all aspects of precious metals, it has been the vision of the IPMI to provide a publication available to the general public that would become a key source of pertinent topics containing high quality publications by experts in their fields of study. Historically, the IPMI has attracted world renowned experts in many fields (including Nobel Laureates Henry Taube, Ei-ishi Negishi, Robert Grubs, Professor Ben Feringa, and David MacMillan) in the dissemination of discoveries, inventions, and industry proven practices. Such information has a total value greater than the sum of its parts as seemingly unrelated innovations from distinct focus areas can be adapted to solve problems. Because of this important characteristic of information exchange, we have decided to create a digital journal, available to the general public, that will not only communicate state of the art discoveries and sound practices, but will also review historical communications from the IPMI’s archives that have value and use even in today’s environment. On behalf of the members and leaders of the IPMI, we hope you will find value in this new publication.

Dec 1, 2023