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By A. C. Fieldner

This report is the fourth of a series of annual summaries of research and technologic work on coal by the Technologic Branch of the Bureau of Mines. The coal research program of the Bureau has been broadened and made more flexible to adapt it to changing conditions and needs of the coal industry, and as a result information as to the properties and composition of coal has been increased and new and improved practices in mining, preparation, and utilization of coal have been devised. The present

Jan 1, 1940

By P. Cicmanec

Mining activities in the territory of Slovakia have a long history. Mining techniques have developed rapidly in the last centuries. This paper deals not only with mining history, but also with underground brown coal mining, magnesite mining and other mining activities at present and sustainable developments of the mining industry in the Slovak Republic. This paper looks forward in the context of mineral raw materials in Europe (Global Europe, 2012).

Aug 1, 2013

By AIME AIME

CERTAINLY in point of attendance, and doubtless in several other ways as well, the 147th meeting of the A.I.M.E. was the best ever held. In times of depression, mining engineers and metallurgists have plenty of time to come to the Annual Meeting but money is scarce; at the height of industrial activity they have plenty of money but no time. "The current period of transition seemed to provide ideal conditions for' both the preparation of papers and attendance at their presentation. The weather made even the Californians present envious though the weather man gets no credit, for rain and snow was what he willed. Among the elevator men, the miners have the reputation of being the toughest crowd to handle, though the best natured, withal, of all the engineering groups that meet in the Engineering Societies Building. This year Your inquiring reporter was told, "it was the damnedest meeting I ever saw; they

Jan 1, 1937

By Jorge Díaz A

El presente texto revisa los métodos utilizados en las minas de tajo de abierto como son la perforación, disparo y seguridad y así mejorar los standars y el rendimiento futuro en la industria minera. Respecto al primer método empleado, se analizan los factores que afectan el rendimiento de brocas y cómo dicho factores varían, impidiendo la adaptación de prácticas universales de perforación. Asu vez, estos mismos permiten seleccionar el tipo de broca adecuado y mejorar el máximo rendimiento del mismo. En cuanto la voladura y los explosivos, se revisan las variables fundamentales que ejercen una influencia sobre el resultado de un disparo y así realizar un estudio comparativo de los agentes explosivos en uso, tratando de interpretar el mecanismo de la explosión y a la vez aplicarlo a las diferentes formaciones presentes en Cerro. Finalmente, se describe la organización del sistema de seguridad y las obligaciones de este comité en la industria minera.

Aug 20, 1965

By Sam Bang Jr, Rodney Burke

As mining progresses in the West, the depth of material has increased, making highwall stability a major factor in safety and production. The Jim Bridger Coal Mine’has made highwall stability a priority, concentrating on safety as well as increasing and improving production. Overburden depths are increasing dramatically; the geological environment consists of medium to sot? material, faulting, water, and current pit alignment not favorable to joint planes. Angle drilling the presplit at 20 degrees became necessaryas vertical presplit drilling produced wall failures.

Jan 1, 1998

In 1960, the Secretary of the Interior, acting under the provisions of Public Law 454, 80th Congress, appointed a Lignite Advisory Committee to aid in programming research on coal (lignite) of the north-central area. The chairman of this committee is the Secretary of the Interior or his delegated representative, and in all meetings held during 1960 and 1961, the Director of the Bureau of Mines, Marling J. Ankeny, has presided. The members of this committee were R. W. Rovelstad, President, Baukol-Noonan, Inc., Noonan, N. Dak. W. E. Keller, Vice President, Northwest Division, Truax-Traer Coal Co., Minneapolis, Minn. A. M. Cooley, Professor of Chemical Engineering, University of North Dakota, Grand Forks; N. Dak.

Jan 1, 1963

By J. A. Herbst

A state of the art computer simulation package, named UTAH-MODSIM is being developed. This package can run on a mainframe (eg. UNIVAC) as well as on a microcomputer (eg. IBM/PC with at least 512 kBytes of core memory). Friendliness was the major concern in developing this software. The user simply generates a complete flowsheet by presenting the flowsheet on a graphics terminal. This flowsheet defines the circuit to be simulated. With the minimum required data, the user can obtain a complete mass and water balances within a few minutes. Moreover, this package will provide scale-up and capital cost information of specified equipment relevant to design. In order to illustrate the utility of this software, three design examples are given. They are: a) A typical multistage crushing plant. b) A reverse closed grinding circuit comparing one stage with two stage classification. c) A standard closed grinding circuit suitable to liberate a specified fraction of chalcopyrite from a copper ore.

Jan 1, 1986

By Euclid P. Worden

INTRODUCTION Today, conventional raise boring is an accepted method of development in underground mines and on major construction projects. Over the years that this technique, and its associated machines and tools, have been under development, many articles have been written on the subject. To a great extent, these papers have reported operating results of one or more specific projects or have been generalized reviews of state-of-the-art machines and tools. This paper is intended as a review of the technique from an operational standpoint. Conventional raise boring, as opposed to the related variants box hole drilling and underground blast hole drilling, is a two step process consisting of the pilot hole drilling and reaming cycles. This author has covered the subject of pilot hole drilling in another article (1) . A good review of the current machines and equipment has been presented by Monroe (2) and an overall review of this entire technology was published by E&MJ (3) and Mining Journal, April, 1983 (4) . The subject of the reaming cycle is presented here together with some of the technical aspects of how the drilling tools are intended to be used. OPERATIONS Bit Change After the pilot bit has broken through at the end of the pilot hole cycle, a changeover takes place at both the machine and

Jan 1, 1985

[This Report represents the culmination of work perfomed under Contract No. .,JG1551A8 for the U.S. Bureau of Mine.The &apos;.:o-< embeded a site evaluation, engineering E:-y- ,, esign, and preparation of specifications for construction of a Transport Research 7 :4 (HTRF)The HTRF is designed as a research facility J evaluate the hydraulic transport of large lump coal at a prototype ;e scale. The HTRF is to be constructed and operated by the Pittsburgh and Safety Research Center of ;. re U.-AN a*, their Bruceton, Pennsylvania test center. In terms of technical capability, the HTRF will have transport pipeline:: of -, twelve-, and eighteen-inch diameter _&apos; with supporting coal handling n , water forage a.^ &apos;d conveyance, mixing, pumping, and dewatering equipment, plus instrumentation and controls. Maximum design velocity 13 20 ft/sec.; solids concentration, by, volume, will; 1 be a maximum-- of sixty, percent. Each test loop is designed to accommodate solids of up to one-third the diameter e - of the pine. The Final Report Pr.-&apos;I-rents information of t HTHF,. including the site evaluation, design criteria, a description of the a description of the procedure to be used for operation of the facility, an estimate of the cost to construct the f^Cilit:r, 1 p el_~lli.&apos;iU construe`, icn Schedule, and a construction suicJ_iicaT.l_ccn&apos;. T e c011SLr?Jc&apos;.ion soecl_ i.on _ccnta_i:s technic.&apos;..i re7,uir: (-n`,s for !&apos;urr1S~ &apos;~latcr..al. and ec-uipr,ent for :":C1 C_`:_C ti on of ti,_ H ice&apos; u:&apos;.:i ._II u s(-.6 for ~.Iir: .3!7 soliciting bids. `.l_o included n cc&apos;;,art_- c?r~.air sV:et..: :s ^nd rr^.?]

Jan 1, 1976

By F. Lowell Lawrance

JOHN SMITH, citizen of the U.S.A., has become so accustomed to reading that Congress has appropriated billions of dollars to pay war costs. that he no longer is impressed by relatively small figures, such as several hundred thousand or a few million, in connection with Government departments.

Jan 1, 1944

By James P. Sloss

A PERMANENT assay office is commonly established as part of the general plant equipment of operating gold and silver properties, but during the development stage of a mine, the cost of such an office is usually so assay work must be done elsewhere. In most instances only a few samples will be taken each day, but if the mine is to be developed scientifically, the analyses of those samples will guide further development. Under such circumstances, the time element in assay returns is important, since the lapse between the taking of the samples and the receipt of results may determine the success or failure of a small-mine operator. The following description of fur-

Jan 1, 1935

By Kasimcan Koruk, Julian M. Ortiz

A geological model accounting for uncertainties possesses important advantages for resource estimation. Machine learning algorithms (MLAs) employed on multivariate geochemical datasets open up ways to new methodologies for such geological models with ease in comparison to traditional geostatistical methods. This article proposes a two-step MLA with an ensemble implementation to define geological domains and their uncertainties based on geochemical data. The proposed workflow is applied hierarchically on a dataset from a porphyry copper deposit to perform binary classification that can be attributed to alteration domains.

Mar 1, 2024

With the advent of the environmental "green" movement of the 1960s, eventually leading to Earth Day 1970, Congress responded by passage of the National Environmental Policy Act (NEPA), 1970. NEPA gave impetus to a flood of federal acts and laws in the subsequent three decades. Many of those protecting man&apos;s environment, health, and well-being also affect mining. For purposes of this chapter, a current mineral law summarization lends itself to a division into two parts: viz., Part I, General Mining Law, and Part II, Enviromining Law. The word enviromining has been coined by the author and is defined and used herein as those federal and state statutes and regulations that were created to provide protection and preservation of man&apos;s environment, health, safety, and welfare, and they have particular application to and affect on mining activities. They are listed and treated under Enviromining Laws in Part II. Mining, as a basic industry to provide the essential minerals for mankind&apos;s necessities and well-being, truly reflects the mining industry&apos;s slogan, "If it can&apos;t be grown, it must be mined." Without the basic minerals and rocks won from the earth by mining and mineral processing for their valuable physical properties or chemical constituents, man would soon be forced to revert to the cave-dwelling age. Unfortunately, for man to survive in the "manner of life to which he has become accustomed," he is caught between the demands of cleaning up his deteriorating environment and a continued supply of his basic requirements and amenities for daily living supplied by mining of the earth&apos;s minerals. He must have "clean living" at the same time with "good living;" neither is expendable. A very high pricetag accompanies this essential and critical choice which must be paid by society. The United States is internationally recognized as the world leader in environmental matters. Many countries are following suit, principally the other Anglo nations. Because US law is founded and based on English law, on occasion, Anglo-American law is referred to and cited as authority in litigation anywhere in the Anglo-American world of jurisprudence. For this reason, and because mining and the industry is international in nature and operations, some British Commonwealth cases will appear in various topics. If the case is of interest to the reader, further inquiry at a law library may be made through use of the case&apos;s style and citation given. "Style" refers to the name of the litigating parties. "Citation" refers to the law publication in which the case and decision may be found, as well as the jurisdiction and court of decision. Citation of cases from the United States and British Commonwealth nations is explained under Case Citation Explanation. Space and time limit exhaustive treatment of subjects and covering all geographic and jurisdictional areas. This chapter is intended as a broad outline and is based on the author&apos;s master&apos;s thesis at the University of Missouri-Rolla, 1992. The following Case Citation Explanation provides guidance on formatting of citations.

Jan 1, 1994

By Robert Leach

THIS paper gives a brief summary of the process of manufacture of sterling silver, and some of its more important physical properties, as observed in commercial production of rolled sheet and wire. Although papers have been published by Turner and Smith,1 Rose,2 Sperry3 and Jordan,4 there are few technical data available, and unfortunately the time allowed for the preparation of this paper has not been sufficient to make it as comprehensive as the title might indicate. ANALYSIS OF STERLING SILVER Fine or pure silver is too soft for coinage and the manufacture of articles in which strength and resistance to wear are desired. From the earliest times of which we have record, copper has been the metal generally used to harden silver. Analyses of coins and silver articles from ancient tombs show varying amounts of copper, and old Roman silver objects in the British Museum have approximately the same analysis as our sterling. The first authentic record of the establishment of a standard alloy is during the reign of Henry II in England. During the twelfth and thirteenth centuries, the people in the Eastern Provinces of Germany had a reputation for the standard and purity of their silver coinage, and it is said that Henry II employed some of these Easterlings, as they were called, to improve and standardize the English coinage, which had become debased. The peculiar standard adopted is probably accounted for by the system of weights used. A troy pound contains

Jan 1, 1928

By N. H. J. Freire, D. Majuste

In this paper, the effects of some organic compounds on the current efficiency, cell voltage and specific energy consumption during nickel electrowinning, and on the deposit features (morphology, crystallographic orientation and nanohardness) were described. The organics tested here (extractant, diluent, flocculant, lubricating oil and acid mist suppressant) are currently used in industrial plants. The results indicated that only the flocculant and acid mist suppressant exhibit relevant negative impacts on the current efficiency and energy consumption. The current efficiency dropped from 93.6 % (organic-free solutions) to 86.0 % and to 92.8% in electrolytes containing 100 mg.L-1 of acid mist suppressant and flocculant, respectively. At this concentration, their addition to the electrolyte led to increases of the specific energy consumption in the order of 18 % (acid mist supressant) and 2 % (flocculant). Cyclic voltammetry showed that Ni nucleation occurs at more negative potentials at 50 and 100 mg.L-1 of these organics in the electrolyte, thus indicating an inhibition of the deposition process. The deposit quality decreased at the higher concentration of all organics, when more hydrogen pitting was observed. The acid mist suppressant caused delamination of the Ni deposit at 50 and 100 mg.L-1. The addition of 100 mg.L-1 of flocculant and acid mist suppressant to the electrolyte increased the nanohardness of the deposit around 31 and 72%, respectively. The increase in Ni deposit hardness may lead to a decrease in the material ductility, thereby affecting the stripping and cutting of Ni sheets. Our findings may be helpful since strong adverse effect of some organics that may be present in the electrolyte were identified, thus the industry can control and optimize the organic´s dosage in the corresponding operations.

Jan 1, 2016

By Jeffrey A. Yonkey, Timothy J. Lutz, Jacob L. Carr, Christopher C. Jobes

"Since 1984, there have been 39 fatalities involving striking and pinning of the operator and other workers by the continuous mining machine (CMM). In January 2015, the U.S. Mine Safety and Health Administration (MSHA) finalized a regulation to require proximity detection systems on all continuous mining machines except full-face machines (MSHA, 2015). Proximity detection systems are designed to stop machine motion to protect miners from striking/pinning hazards. Several MSHAapproved proximity detection systems are commercially available.NIOSH researchers have been involved in the development and testing of proximity detection technology since creating the HASARD system (Schiffbauer, 2002) and have recently conducted research intended to develop more advanced proximity detection technology for CMMs (DuCarme et al. 2013; Jobes et al. 2012; Carr, DuCarme et al. 2013 and Carr, Li et al. 2013). In addition, NIOSH has also conducted research investigating how the signals of a proximity detection system propagate (Li, Carr et al. 2013 and Li, Jobes et al. 2012) and have developed a novel method for determining the location of a personal wearable device (PWD) relative to the magnetic field generators (Carr et al. 2010 and Jobes, et al. 2012).To evaluate the performance of proximity detection systems implemented in industry, NIOSH researchers conducted tests in 2013 on three systems installed on CMMs at three underground mines in Illinois and West Virginia. The results of these tests indicated that, while generally consistent performance was observed, there were opportunities for improving performance. These results were presented at the 2014 SME Annual Meeting (Carr, Lutz, et al. 2014). Since that time, second-generation systems have become available to the industry and are becoming more commonly used.Beginning in early 2014, NIOSH researchers conducted underground testing of these secondgeneration proximity detection systems installed on CMMs. Five tests were conducted on four installations of second-generation proximity detection systems, with one installation being tested twice. The tests were conducted at mines located in Illinois, Virginia and Kentucky with seam heights ranging from 137 cm (54 in.) to 213 cm (84 in.). These tests were conducted using the same test protocol used during first-generation testing, which is summarized in the following section."

Jan 1, 2014

By Shelby Z. Palya

"INTRODUCTION The Bureau of Mines was established in the public interest to conduct inquiries and scientific and technologic investigations concerning mining and the preparation, treatment, and utilization of mining substances; to promote health and safety in the mineral industries; to conserve material resources and prevent their waste; to further economic development; to increase efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting those industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the Bureau to ""disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act.""In accordance with this directive, the Bureau reports the findings of its research and investigations in its own series of publications and also in articles that appear in scientific, technical, and trade journals; in proceedings of conventions and seminars; in reference books; and in other non Bureau publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make the kind of list and index presented in this special publication both necessary and valuable. This issue describes reports and articles published during the period January 1, 1975, to December 31, 1979. It supplements the 50-year list of Bureau publications issued from July 1, 1910, to January 1, 1960; 2 the 50-year list of articles by Bureau authors published outside the Bureau from July 1, 1910, to January 1, 1960; 3 the 5-year lists of publicatioll3 and articles, from January 1, 1960, to December 31, 1964,4 from January 1, 1965, to December 31, 1969,5 and from January 1, 1970, to December 31, 1974; 6 and the annual lists of Bureau publications and articles from January 1 to December 31, 1975,7 from January 1 to December 31, 1976,8 from January 1 to December 31, 1977,9 and from January 1 to December 31, 1978.10"

Jan 1, 1980

By Jacques B. Wertz

Both the San Andreas fault complex and the Murray fracture zone are apparently found to be contemporaneous with the Laramide mineralization period. Their compounding effects certainly have disturbed the Texas lineament belt and its components with serious lateral offsets and most probably have been instrumental in allowing intrusives to be emplaced as well as mineralization to accompany these intrusions at some of the fracture intersections. While the main fracture centers can be almost accepted as being structurally linked together, the Texas lineament trend definitely predominates, exerting a prevailing direction to graben (Silver Bell) and to elongated depressions (Bisbee). That this lineament belt also influenced the concomitant mineralization seems a logical inference. The orebodies are generally found at intersections near the most centrally-located intrusive with a distance varying from contiguity to one or two miles. The Southeast Arizona copper province owes its existence primarily to a particularly favorable structural setting of broad semi-continental scope. Thus, various regional structural elements are to be considered as possibly direct or remote cause for the widespread mineralization, although the one or the ones really responsible may never be singled out. There arc three basic regional elements: (1) The north-northwest-trending anticlinorium that diagonally crosses Arizona is quite obvious because many mountain ranges follow this direction. This anti- clinorium, which merges northward into the Wasatch-Jerome Belt, marks a broad zone of weakness where tension seems to prevail. Mineralized trends such as Jerome-San Manuel-Bisbee may give some weight to the economic value of this structural element. (2) Northeast-trending fractures, parallel to the Colorado Mineral Belt (Landwehr, 1967), appear troincident with mineralization as evidenced by the Questa-Grants-Morenci and the Lordsburg- Tyrone-Santa Rita alignments. This structural direction is accepted as one of the most economically significant in the Southwestern United States. (3) The Texas Lineament.

Jan 1, 1970

By T. J. Otto, G. C. Lindeque

Productivity is improved by increasing the ratio of output to input. In an operating open-pit mine, improving the productivity of heavy mining equipment (HME) enables the unit cost of production to be reduced. To optimize HME productivity, the Kolomela open-pit iron ore mine transitioned to an enhanced short-term mine planning (STMP) process that supports the application of a manufacturing-type operating model. At the core of the enhanced STMP process is a focus on integration across the open-pit mining value chain. The interdependencies between mining activities are highlighted and emphasized, thus ensuring that mining activities are synchronized. The improvements related to HME productivity were monitored from 2019 to 2020. The utilization of mining area in the Leeuwfontein pit improved from 71% to 90%, and the blasting frequency reduced by 14% while the average blast size increased by 17%. The distance travelled during shovel relocations between mining phases reduced by 16%, and the lost time associated with drills relocating reduced by 53%. These productivity improvements resulted in an 11% increase in the loading rate of the main waste shovel at Kolomela from 0.9 Mt/month in 2019 to 1.0 Mt/month in 2020. The enhanced STMP process can be adapted to other open-pit mining operations.

Nov 1, 2021

By Herbert Clark Hoover, Lou Henry Hoover

SINCE the Sixth Book has described the iron tools, the vessels and the machines used in mink, this Book will describe the methods of assaying1 ores; because it is desirable to first test them in order that the material mined may be advantageously smelted, or that the dross may be purged away and the metal made pure. Although writers have mentioned such tests, yet none of them have set down the directions for performing them, wherefore it is no wonder that those who come later have written nothing on the subject. By tests of this kind miners can determine with certainty whether ores contain any metal in them or not ; or if it has already been indicated that the ore contains one or more metals, the tests show whether it is much or little ; the miners also ascertain by such tests the method by which the metal can be separated from that part of the ore devoid of it ; and further, by these tests, they determine that part in which there is much metal from that part in which there is little. Unless these tests have been carefully applied before the metals are melted out, the ore cannot be smelted without great loss to the owners, for the parts which do not easily melt in the fire carry the metals off with them or consume them. In the last case, they pass off with the fumes ; in the other case they are mixed with the slag and furnace accretions, and in such event the owners lose the labour which they have spent in preparing the furnaces and the crucibles, and further, it is necessary for them to incur fresh expenditure for fluxes and other things. Metals, when they have been melted out, are usually assayed in order that we may ascertain what pro- portion of silver is in a centumpondium of copper or lead, or what quantity of gold is in one libra of silver ; and, on the other hand, what proportion of copper or lead is contained in a centumpondium of silver, or what quantity of silver is contained in one libra of gold. And from this we can calculate whether it will be worth while to separate the precious metals from the base metals, or not. Further, a test of this kind shows whether coins are good or are debased ; and readily detects silver, if the coiners have mixed more than is lawful with the gold ; or copper, if the coiners have alloyed with the gold or silver more of it than is allowable. I will explain all these methods with the utmost care that I can.

Jan 1, 1950