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By E. H. Burroughs

This bulletin is the fourth in the series of petroleum bibliographies being published by the Bureau of Mines, the three preceding, Bulletins 149, 165, and 180, being compilations for the years 1915, 1916, and 1917, respectively. In this bulletin the same general plan has been followed in arranging the references, but a few changes and additions have been made in the classification, the more important changes being in the classes "Geology and Origin" and "Refining and Refineries." Dl1'ring the year German periodicals were not available, and, as in the bibliography for 1917, references to articles in foreign journals that were not available have been taken' from other sources and credit given to those sources.

Jan 1, 1921

By V. F. Parry

This report is the first substantial description of the carbonizing process and the details of experimental work conducted at the Denver laboratories under a coopeative agreement between the Bureau of Mines and the Texas Power & Light Co. It presents the results of tests on several Texas lignites and other typical western coals that have been processed in the first pilot plant operated at Denver. Investigations on drying fine coal in the entrained and fluidized state have been under way at Bureau of Mines Denver laboratories for several years. Reports on this work were published in 1949 and 19505/ describing the theory and practice of re-moving inherent moisture from the lower -rank coals. The investigation did not include a study of the removal of surface moisture from fine fuel. Private industry in Canada became interested in the possibilities of drying fine coal, employing the closed-circuit system and techniques recommended by the Bureau. Large, commercial-scale drying units were built by a Canadian company, which successfully demonstrated that surface moisture could be removed from fine coal at high efficiency and capacity ill drying units similar in design to those developed by the Bureau.

Jan 1, 1953

By F. E. Harris

The United States produces about 30 percent of the world output of salt. Numerous deposits occur in widely separated areas, but the leading producing States are California, Kansas, Louisiana, Michigan, New York, Ohio, Texas, Utah, and West Virginia. Although no great amount of salt is produced at present in Pennsylvania, the potential sources in that State recently aroused a good deal of interest. The United States salt industry is highly organized; it comprises fewer companies than when small crude works with primitive methods and equipment eked out salt for local needs, but concentration of output brought about by modern inventions and methods of production has improved the quality of the produce greatly and accelerated production.

Jan 1, 1939

By H. E. Powell

This study was made to determine the capabilities and limitations of the hydrocyclone for separating quartz sand from impure clays, Optimum operating conditions for beneficiating typical subgrade clays were determined. Estimates are furnished for installation and direct operating costs of hydrocyclones in such separations. Laboratory models of commercial hydrocyclones were used to beneficiate a suite of fire clays including plastic, semiflint, and flint types, all of which were contaminated with quartz in amounts ranging from 3 to more than 62 percent. Results show that this technique is not limited to a single type of clay but is applicable to clays ranging from plastic through flint, Under proper conditions use of this technique will result in good separation of the sand and good recovery of a useful clay mineral concentrate. Rejection of quartz from the clays investigated ranged from a low of 82.4 percent with an alumina recovery of 71.2 percent to a high of 99.0 percent with an alumina recovery of 85.6 percent.

Jan 1, 1963

By David White

This paper is the result of a comparative study of ultimate coal analyses made and published by the United States Geological Survey. This study, at first casually undertaken to devise an acceptable classification of coals based on chemical analyses, was continued in connection with a microscopic examination of a number of the coals. The initial comparisons, made from a relatively small number of analyses, not only confirmed a previous conviction that the elimination of oxygen incident to the development of a coal is economically far more important than has been generally suspected, but also showed that oxygen is very nearly as harmful as ash in coal. The immediate purposes of the present study were: (a) To determine more definitely, from a comparative examination of a large number of ultimate analyses, the relative importance of oxygen as an impurity in various coals; (b) to illustrate the transition between various grades of coal of similar origin-transition mainly due to progressive devolatilization, brought about more or less directly by dynamic influences; (c) to ascertain the relative proportions of oxygen, hydrogen, and carbon in coking coals, especially with reference to a theory tentatively framed to explain the coking quality; and (d) to forecast the probabilities of successfully treating a large number of coals so as to render them amenable, in a softened condition, to satisfactory study under the microscope.

Jan 1, 1911

By Lars Skogsberg

Work with hand-held power tools can be found in most industries all over the world. This type of work exposes the operators to different kind of loads like gripping-forces, feed-forces, exposure to vibration and noise, holding hot or cold surfaces and the exposure to dust. Designing a power tool with good ergonomics is a matter of finding the best compromise. As a simple example, increasing the mass is not acceptable because it will increase the forces needed to handle the tool. At the same time increased mass will in most cases reduce the vibrations. Vibration disorders related to the use of hand-held power tools has been known and reported since long. It is therefore essential that low vibrating tools are developed and used. The new vibration regulations in Europe, based on the Physical Agents (Vibration) Directive, have put increased focus on the vibration control in industry. Forces acting on the tool cause vibration Tools for industrial use must be of very robust design to withstand the very hard use they are exposed to. Industrial tools are therefore normally designed with the main parts made of metal. From a vibration point of view this means that most tools can be regarded as rigid bodies, especially because the dominating frequency normally is equal to the rotational frequency of the tool spindle or the blow frequency for a percussive tool. These frequencies are with few exceptions below 200 Hz. Handles however can not always be regarded as rigidly connected to the tool. There are several examples of weak suspensions designed to reduce vibration transmitted to the hands of the operator. There are also examples of designs where the handles just happened to be non-rigidly connected and in some cases even in resonance within the frequency region of interest. Oscillating forces act on the tool and the result is vibration. Design principals In all cases forces are the source of vibration. This leads to the three basic principles to control vibration: • Control the magnitude of the vibrating forces. Examples are the balancing unit on a grinder or the differential piston in a chipping hammer. • Make the tool less sensitive to the vibrating forces. Examples can be when the mass of the guard on a grinder is rigidly connected to the tool to increase the inertia of the tool. • Isolate the vibrations in the tool from the grip surfaces. Examples are vibration-dampening handles on grinders or pavement breakers, the air-spring behind the blow-mechanism in a riveting hammer or the mass spring system in a chipping hammer.

Jan 6, 2006

By Scott W. Hazen

This Bureau of Mines report presents the results of a study and statistical analysis of part of the initial exploration churn-drill sampling and some of the subsequent underground diamond-drill-core sampling in the North are body at the San Manuel copper mine, Arizona. These data were derived from regular exploration and mine sampling, not from special samples obtained solely for statistical analysis. The study was conducted as part of the Bureau's continuing program on sampling-methods research. The major objective of the study was to investigate the feasibility of using the techniques of statistical analysis in evaluating sample and assay data and computing grade and tonnage of Ore from porphyry-type copper deposits. It was recognized that using existing data acquired over a period of several years by different methods would introduce problems and limitations for precise comparisons. However, it was expected that the study would provide some general conclusions and certainly a number of preliminary conclusions on the nature of the mineral characteristics and their effect on sampling procedures, the requirements for sampling deposits of this type, and the comparative results of churn-and diamond-drill sampling in the same area of the deposit. All of this information would be essential for future sampling-methods research for computing grade and tonnage of ore.

Jan 1, 1963

By B. E. Blair

"This report presents the physical properties and related geological and petrographic data of some 84 rock types from operating mines, quarries, or blasting research test sites. These fundamental rock data were collected as a quantitative approach to underground mining problems, blasting research, or other related studies; however, the data are equally applicable to any problem wherein rock characteristics are important factors. Stress-strain curves are given where available, and the standardized procedure for determining elastic constants from static tension tests is described. Computed (laboratory) and measured (field) free-medium velocities are compared in those instances where such data are available. A chart is given showing both the optimum and minimum number of test specimens for the various core sizes employed in the Bureau of Mines standardized physical-property tests. Rock-type, geographical, and geological indexes are included to aid the reader in locating physical-property data in this and previously published Bureau of Mines physical-property reports.INTROD'OCTI ONThis report presents the physical properties of 84 rock types tested from 16 different projects (sections 37-52). Two previous physical-property reports 2-3 / (hereinafter referred to as parts I and II) presented data on 160 rock types from 36 different projects (part I, sections 1-25 and part II, sections 26-36).The physical-property data were originally obtained to supplement structural mining problems, seismic studies, or related investigations; however, they should be equally applicable in all fields of studies where the strength, hardness, or other properties of rock are important factors. The properties, determined from laboratory tests performed on diamond-drill core, include the following:"

Jun 1, 1955

By K. R. Dorman

To develop the potential of precast concrete sets as a support medium in underground mines, a three-piece precast concrete drift set was designed for a small opening and tested to destruction in an underground straining frame. Thirty-six tests were made with three sizes of members using three different loading conditions. In addition, 14 members were tested individually in the laboratory. Test results are compared with theoretical calculations. A cost comparison shows the use of concrete sets would be advantageous where conventional wooden timber requires excessive replacement.

Jan 1, 1968

By C. M. K. Boldt

The Bureau of Mines studied the compaction characteristics of metal and nonmetal tailings. Densities of the tailings and zone of compaction influence, compactive effort, and cost of equipment are related to changes in the factor of safety for specific grain-sized tailings and embankment configurations. Field testing was accomplished in two distinct phases. The first phase investigated the effectiveness of using a nuclear gauge on metal and nonmetal tailings to produce rapid, instantaneous measurements of moisture content, wet density, and dry density. The results of the nuclear gauge testing are presented in chapter 1. Chapter 2 presents a comparison of the compactive effectiveness of three different pieces of construction equipment on a coarse-grained metal tailings pond. The three pieces of equipment chosen for study were a DBH track-mounted dozer, a DSOO rubber-tired dozer, and a SP848 vibratory smooth-drum compactor.

Jan 1, 1985

By L. Y. Sadler

This report summarizes the findings of a 9-yr research program, sponsored by the U.S. Department of Energy and conducted by the Bureau of Mines, to evaluate refractory liner materials for coal gasifier reactors. Commercially available refractories were exposed to coal gasifier reactor environments, reproduced in the laboratory with a high-temperature, high-pressure test facility, followed by extensive postexposure evaluation. Thirty-six castable or gunnable refractories and cements and 24 refractory brick were evaluated. The behavior of castable refractories reinforced with stainless steel fibers was also examined. Gas environments that were evaluated included steam, H2, CO2, CO, and typical high-and low-Btu gas mixtures. Exposure pressures ranged from 100 to 1,000 psig, temperatures from 5000 to 1,1000 C, for periods from 50 h to 2,000 h. In some exposures, sodium and/or potassium hydroxide were introduced in order to simulate a high-alkali environment. It was found that intermediate-and low-alumina refractories produced from domestically available raw materials, rather than high-alumina refractories produced from imported raw materials, gave the best service as liner materials and that alkali attack was probably not a serious problem with most refractories. Based on the results of this program, good choices of refractory liner materials for gasifier reactors can be made.

Jan 1, 1984

By Charles E. Semler

The possible utility of selected compositions in the systems SrO-ZrO2-MgO and SrO-ZrO2-Dolomite for commercial refractory products was confirmed in this study. Specifically the compositions of interest are located in the sub-systems SrZrO3-ZrO2-MgO and SrZrO3-ZrO2-Dolomite. Both sub-systems have regions that are not affected by hydration, but the sub-system SrZrO3-ZrO2-MgO has a larger candidate compositional region. Solid state phase relations were determined for the subject systems over the temperature range 1600°C to 1300°C, with compatibility diagrams presented for each. The systems appear to show good refractory character with no apparent low melting compositions. As the compositions of commercial interest lie mostly in the higher ZrO2 portion of each system, information is presented regarding the firing treatment required to develop stabilized cubic ZrO2. A list of suggestions for further study of these systems, to further delineate the characteristics required for possible commercial utilization, is presented.

Jan 1, 1982

Minerals are vital to any industrialized civilization. Annually, the United States uses more than 4 billion tons of new mineral materials, or about 40,000 pounds per person-about half being mineral fuels and the other half being metals and nonmetallics. Stable and economic domestic mining, mineral, metal, and mineral reclamation industries are essential to the economy. The value of United States energy and processed materials of mineral origin exceeds $200 billion annually. Although a number of minerals are imported, especially some designated as "strategic and critical," most U.S. mineral supplies are derived from the domestic mines and processing facilities that you will be seeing, reading about, and visiting as you use this visitor guide. We hope you enjoy your experiences. This pamphlet, a guide to mining and mineral operations that may be observed or visited and some other points of interest relating to minerals, is in-tended to aid tourists and students who are interested in mining. Some may wish to study our Nation's romantic past; others may plan to enter the minerals industry as a career; still others may have a primary interest in conservation practices. The pamphlet is also intended to aid State and local officials, Chambers of Commerce, and mining firms in answering some of the many questions of tourists and students.

Jan 1, 1977

By F. W. Horton

Investigation of an extensive deposit of chromite-bearing actinolite-talc schist situated on the summit of Casper Mountain, 10 miles south of Casper, Wyo., was one of the first projects Undertaken by the Bureau of Mines under the Strategic Materials Act (Public 117, 76th Cong., Ch. 190, 1st sess.), for which an appropriation became available August 9, 1939. During the previous summer; the Geological Survey? made? a magnetometrical survey of the area in which the schist occurred. It was exposed in several small lenses and two larger ones aggregating about 19?acres in area. Although the occurrence of chromite here had been known for many years, the only work done on the deposit was the digging of? a few shallow pits on some of the more promising outcrops. From August 23 to December 3, 1939, the Bureau of Mines investigated the larger of the two main schist bodies. Twenty-four trenches having a total length of 8,073 feet were dug across the deposit, and its subsurface extension was explored by 3,623 feet of diamond drilling. Over 32 tons of samples were shipped to the Metallurgical Division of the Bureau of Mines at Reno, Nev., for reduction, analysis, and ore testing. In all, there were 853 individual samples. Geological maps, based upon examination of outcrops, trenches, and drill cores, as well as a contour map of the area were made by the Geological Survey.

Jan 1, 1949

By D. Harrington

The record of fatalities from mine explosions during the past 2 fiscal years has been anything but encouraging; more men were killed by explosions (379) than were killed from the ante cause during to' preceding 6 years combined (368). The reason for the large increase in the number of explosion fatalities during the past 2 years as compared with the previous 6 years is not entirely clear. In some instances, there has been laxity in the enforcement of State mining laws; in others, both workers and operating officials is have failed to observe recognized precautionary measures to prevent explosions. In many of the explosions that lave occurred within the asst few years in mechanized mines it has been evident that speed of operation and a demand for maximum tonnage at minimum cost resulted in neglect of ordinary safety measures.

Jan 1, 1942

The Bureau of Mines is responsible for a broad spectrum of programs for meeting the diverse and changing mineral resource needs of the Nation. These programs are managed by the Director and two Deputy Directors, who formulate general policy and program direction from the Washington, D.C., headquarters. Bureau program activities are classified into two major functions, minerals research and minerals information and analysis. A senior advisory staff, consisting of the Chief Staff Officer and Chief Scientist, provides advice and consultation to the Director on a wide range of scientific and technical matters and acts on behalf of the Director to maintain liaison with other government agencies, both foreign and domestic, mineral industries, and professional societies. The Minerals Research Directorate Technological research and development in minerals have long been cornerstones of the Bureau of Mines. The Minerals Research Directorate performs this work. Re-search functions cover the extraction, processing, use, reuse, and disposal of mineral materials; the reduction of health and safety hazards in mining and processing; and minimizing undesirable environmental effects. The production, conservation, sale, and distribution of helium is also conducted under the Research Directorate.

Jan 1, 1981

By John E. Conley

The great demand for metallic aluminum for the prosecution of World War II caused the consumption of bauxite, the common ore of aluminum, to increase greatly. Prior to the war, the domestic deposits 'of bauxite, which occur chiefly in Arkansas and less extensively in Georgia, Alabama, and Mississippi, supplied only: about 30 ,percent of the ore required for aluminum-metal production and approximately 40 percent of alumina for all purposes. Enemy activities during the war seriously interfered with shipment of bauxite from the normal peacetime source in Surinam, Netherlands Guiana, South America, and focused attention on the necessity for increasing production from known domestic deposits. Even in peacetime, the production of aluminum ore in the United States could not satisfy requirements. Field drilling and exploration by Bureau of Mines engineers resulted in the discovery of important tonnages of high-grade bauxite suitable for treatment by the conventional Bayer process, Although an ore containing approximately 55 percent Al2O3 and only 2 to 4 percent SiO2 is preferable, it was necessary to use ores containing up to 8 or 10 percent SiO2. Because of the lower recoveries of aluminum with increased silica content, the Reconstruction Finance Corporation, through the Metals Reserve Company, established a base price of $4 for a 50-percent Al2O3 ore, containing 13-percent silica, with a premium or penalty of 14 cents for each percent of Al2O3 over or under 50; each percent of SiO2 under 13 was awarded a 20-cent premium, and each percent over 13 suffered a penalty of 43 cents; all prices were on the basis of 1 long ton of ore, dry basis.

Jan 1, 1949

By D. Harrington

The number of fatalities from mine explosions for the fiscal year 1945 dropped below that of the year before; continued improvement over the record of the years from 1940 to 1945 is hopeful, but the number of reported explosions has increased rather than diminished, and the number of victims claimed by explosions is often more definitely a factor of chance than forethought. Mine fires and explosions can be eliminated through the methods now well-known to those well-informed in matters pertaining to safety in mining but ignored by many coal-mine operators and employees who follow procedures of the past or their own short cuts, regardless of disasters that may result: Tried and proved safety measures for preventing mine fires and explosions have been recommended to the mining public repeatedly, yet only a relatively small but far-sighted minority have adopted these measures and made them a part of operating practice. That far more explosion disasters did not occur in 1945 is fortunate. In 1945 a coal-mine fire of electrical origin caused heavy loss of life, while several others from the same cause were controlled with but few fatalities; this hazard is now being curbed temporarily to some degree after the bad record of the two preceding years, but a real solution of the problem has not been reached, although cooperating committees trying to produce at least some answer have made progress.

Jan 1, 1946

By R. R. Wells, G. M. Potter, A. O. Ipsen

This paper gives results of laboratory and pilot - plant investigations of concentration of western manganese ores during the Bureau of mines manganese-development program initiated in December 1940. The data summarize results obtained from laboratory investigation of concentration of ores from three properties in southeastern Arizona . The high - grade Gray - claims lot B ore , a product of hand sorting , is marketable directly or after sintering treatment . Intermediate - grade lot A selectively mined ore would be marketable after sintering as a plus 35 percent manganese produce , but gravity concentration methods were employed effectively to produce high - grade manganese concentrates with over 80 percent recoveries . Complex association of fine - grained manganese oxides , calcite , and fluorite in a siliceous ground mass limited the recovery of high-grade manganese concentrates obtainable from the low-grade Pyrolusite -group ore . A recovery of 63.7 percent of the manganese was made by flotation in a concentrate that sintered to plus 48 percent manganese grade . The low-grade Davis ore contains iron and manganese oxides too intimately associated to permit production of marketable manganese products . However , good rejection of calcite gangue was obtained by flotation , and the enriched manganese - iron product might have value as a spiegeleisen ore .

Feb 1, 1946

Develop hydrometallurgical or pyrometallurgical recycling methods to recover valuable rare-earth compounds from various forms of NdFeB magnet scrap. Background The U.S. Bureau of Mines (USBM) has developed technology to treat and recycle a variety of wastes containing valuable and strategic metals. As part of this effort, the USBM developed a process to separate neodymium and other valuable rare earths from iron in NdFeB magnet scrap (fig. 1). Since this scrap typically contains nearly 30 weight percent neodymium and since the demand for neodymium is constantly increasing, cost-effective methods for scrap treatment could have a significant impact on industrial expenditure and materials supply in the expanding area of magnet manufacture. Approach A hydromctallurgical, H2SO4 dissolution-precipitation process provided the most effective treatment for separating rare earths from bulk NdFcB magnet scrap (fig. 2). Precipitation of neodymium-alkali sulfate double salt proved advantageous over direct precipitation of fluoride or oxalate products. This double salt is easily converted to a variety of useful rare-earth compounds, which eliminates many of the materials-handling and economic problems inherent with direct precipitation. Following rare-earth precipitation, dissolved iron was removed from the acid leach solution by precipitation as a jarosite.

Jan 1, 1993