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By Donald F. Reed

Deposits of gray hematite occur in two districts in Talladega County, Ala., the Emauhee-Tallasechatch and Weewoka, both in the; vicinity of Wintorboro, 50 miles east of Birmingham. The deposits were investigated by the Bureau of Mines in 1945 and 1944. Approximately 15,000 feet of diamond drilling was done and 6,000 linear feet of trenches excavated and sampled.

Jan 1, 1949

By L. J. E. Hofer

"INTRODUCTION This paper is riot to be considered a complete survey of data on carbides; it is only an attempt to correlate the more reliable of the existing data of interest in connection with the Fischer-Tropsch synthesis, and its purpose is to guide future experiment and thought.A general review of the literature on the Fischer-Tropsch synthesis will be published in the near future as a chapter by H. H. Storch for a book entitled, ""The Chemical Utilization of Coal,"" edited by H. H. Lowry. This chapter covers the literature up to l9). It is planned to bring the review up to date in a comprehensive bulletin on Synthetic Liquid Fuel Processes to be completed during the next year. ACKNOWLEDGEMENTSThe author discussed the significance of the data with several members of the Physical Chemistry and Hydrogenation Section.THE PREPARATION OF CARBIDES OF IRON, COBALT, AND NICKELThe reaction of carbon monoxide with Fischer-Tropsch metals was first studied in a quanitaive way by Bahr and his coworkers. The contents of their first papers, 3/ 4/ 5/ which deal with the action of carbon monoxide on nickel, cobalt, and iron, will be described in the following paragraphs, together with the pertinent results of other investigators."

Jul 1, 1944

By E. D. Gardner

This paper is the third of a series of three on placer mining in the western United States. The first paper4 discusses the history of placer mining in the Western States and the production of placer gold, geology of placer deposits, location of placer claims on public lands, sampling and estimation of gold placers, and classification of placer-mining methods, together with hand-shoveling and ground-sluicing. The second papers deals with hydraulicking, sluice boxes and riffles, recovery of gold and platinum from placer concentrates, treatment of amalgam, and marketing of placer gold. The discussion of sluice boxes and subsequent subjects in the second paper applies to all forms of placer mining. The present paper treats of dredging and other forms of mechanical handling of placer gravels, and drift mining.

Jan 1, 1934

By Michael J. Jorgensen, Pranathi B. Aedla, N. K. Kittusamy

Risk factors associated with the development of muscu­loskeletal discomfort and disorders during the operation of heavy mobile equipment include whole-body vibration and awkward and sustained joint postures of the shoulders, neck, and trunk. Cab design may influence awkward postures of the joints, and task duration may influence duration of exposure to awkward and static postures and whole-body vibration. To reduce exposure to risk factors related to the interface between cab design and task, it may be necessary for manufacturers to address cab design. This study assessed the repeatability of a cab design checklist developed to evaluate various design characteristics that can influence exposure to risk factors for musculoskeletal discomfort. The ability of the cab design checklist to identify posture-related deficiencies of design was also assessed. The checklist was used by two administrators across 10 pieces of heavy construction equipment. Video analysis was performed to quantify postures of the neck, shoulder, and trunk; correlation analysis was used to determine whether specific questions from the checklist were associated with the identification of awkward postures. The repeatability assessment resulted in kappa coefficients ranging from 0.52 to 1.0 (good-to-excellent reproducibility) across each piece of equipment, and an overall kappa coefficient of 0.77 (excellent reproducibility) when considering all equipment together. Results from the correlation analysis showed that shoulder flexion posture was correlated with scores from the cab design checklist. However, results of the cab design checklist were not significantly correlated with shoulder abduction or awkward postures of the neck and trunk. Results suggest that the cab design checklist may be useful for identifying cab design characteristics that need further improvement and for identifying design characteristics that increase shoulder flexion. The strength of the repeatability assessment suggests that outcomes of the cab design checklist administered by different individuals may be consistent, independent of the type of equipment being assessed.

By R. S. Dean

[During the past fiscal year the Metallurgical Division has made important contributions along the lines dictated by the Bureau policy of conservation of domestic mineral resources through Its investigations include determining of fundamental data of metallurgically important materials improvement of standard ore-treatment method to eliminate waste and improve the grade or recovery of the products; and development o new metallurgical processes.]

Jan 1, 1940

By Donald W. Mitchell

Studies were made in the Bureau of Mines Experimental coal mine to evaluate the effectiveness of a few extinguishing agents and techniques for controlling a fire on a simulated mining machine. The investigation showed that water containing an alkali-metal salt or a surface-active (wetting) agent was more effective than water alone. For close attack, fog applications was the most effective technique studied; high rates of agent application controlled the fire more quickly than low rates. The ability to control the fire increased as the distance of attack decreased. Dry powders controlled the fire when applied by shovel but not when applied airborne by rock-dust distributor or by hand fire extinguishers. Dry alkali-metal salt powders (potassium and sodium bicarbonates and sodium tetraborate) quenched the fire more readily than limestone dust. In each instance the finer powder, the greater its effectiveness. In an open ventilated entry, smoke and hot gases backed against the air currents. An airspeed of 230 feet per minute was required to permit approach to within 10 feet of the fire. At lower airspeeds, approach could be made by extending the brattice across the bottom two-thirds of the entry, by pushing the smoke ahead with water sprays, or by discharging dust from a rock-dust distributor. In a dead-end entry, the fire was approached to within 30 feet by coursing fresh air along an airtight line brattice; however, it was safer, easier, and less time-consuming to attack the fire from a fresh-air base 100 feet away with a solid stream or by high-expansion foam; the latter method was more effective.

Jan 1, 1961

By G. S. Scott

Mine fires have occurred since the mining of coal was begun, and they are still occurring. The resulting economic waste may become considerable (219),3 especially if a fire is allowed to assume major proportions or to get beyond control temporarily. It is important, therefore, to act promptly whenever a fire is suspected and to have every action count. To do this effectively, it is necessary to know at the earliest possible moment and thereafter what is happening in a remote or inaccessible area. It is equally important to know before¬hand what may be expected as a result of any proposed combative measure. The logical method of combatting a fire demands the cooperation of both mining engineer and chemist. They should decide the course of action to be taken, drawing upon the mining engineer's intimate knowledge of the physical structure of the fire area, the cost and time required for proposed operations, and the probable efficiency with which they could be carried out, and upon the chemist's knowledge of the results to be expected therefrom.

Jan 1, 1944

By David A. Lipton

In the summer of 1985, at the request of the U.S. Forest Service, the U.5. Bureau of Mines examined the 109,000-acre West Big Hole study area to evaluate its identified mineral resources. The study area is in Beaverhead County, about 50 mi west of Dillon, MT. Four lode properties within or adjacent to the study area contain an estimated 452,000 tons of identified subeconomic gold-silver resources. Resources ranged from 900 to 302,000 tons, with estimated grades between 0.02 and 0.23 oz/ton gold and as much as 4.8 oz/ton silver. Gold, silver, and base-metal content in samples of poorly exposed mineralized structures indicate that exploration may identify resources on 18 additional lode properties within the study area and 5 properties adjacent to it.

Jan 1, 1988

By D. J. Dollhopf

An overburden handling dragline operation was conducted at a strip mine near Colstrip, Montana. The objective of the demonstration was to determine the degree a dragline could mix overburden inhibitory zones during the spoiling process. In order to quantify the mixing process the overburden was: 1) scatter spoiled; 2) dump spoiled; and 3) spoiled in a normal manner. This demonstration was part of an effort to investigate means of reestablishing non-polluted hydrological systems in areas where surface mining directly impacts shallow ground-water resources. When inhibitory material constituted < 5% of the total overburden volume, such material was essentially not detectable in the resultant spoil pile. When inhibitory material exceeded 15% of the overburden volume it was always found in the resultant spoil pile, generally with a smaller extent, indicating partial dilution. Inhibitory overburden zones often reappeared at the base or top of spoil piles in the potential aquifer and root zones suggesting the need for selective placement procedures. Scatter spoiling did not appear to be significantly more effective than normal spoiling, however clump spoiling seemed to produce less mixing of inimical zones. Mining activity has reduced ground-water levels within 1600 m of the active pit. The aquifer which is developing in spoils appears to have similar confinement characteristics as those that existed in the premined aquifer. To date no definite trends have been observed concerning changes in surface or ground-water chemistry associated with mining.

Jan 1, 1978

By Reno M. Pappas, Christopher Mark

This report presents results of a U.S. Bureau of Mines study of longwall gob material. The objective of this work was to determine material stiffness properties of the gob for use in numerical models of rock mass response to longwall mining. Photographs of actual mine gob were digitized to obtain approximate particle size gradations of gob material. The gradation curve was shifted down to a lab- oratory scale, and 20 uniaxial compression tests were conducted. Varying the maximum particle size was not found to affect the stress-strain behavior, but changing the gradation appeared to influence the stress-strain behavior. The stress-strain relationship of the simulated gob material was nonlinear, the stress-secant-modulus relationship, was approximately linear, and the stress-tangent-modulus relationship was approximately a second-order polynomial function. Equations were generated from these curves, providing numerical modelers with a means to estimate gob moduli based on the stress level. In addition, the experimental data were statistically evaluated using multiple regression analyses, producing a series of equations to predict the secant and tangent moduli from the given stress level, bulking factor, rock strength, and thickness-to-width shape ratio of the particles.

Jan 1, 1993

By R. S. Dean

[During t!~c past f isc.~l y~:-.r the Xetzllvz-gicd 3ivi oion has made im- portant contribution-, don,- tlie lines rlictnteil by the Bureau policy of con- servation of domestic rnker~l rcsoul-ces throui;h use. During t!~c past f isc.~l y~:-.r the Xetzllvz-gicd 3ivi oion has made im- portant contribution-, don,- tlie lines rlictnteil by the Bureau policy of con- servation of domestic rnker~l rcsoul-ces throui;h use.]

Jan 1, 1940

By Charles L. Kimbell

The year 1979 was a period of increased activity for the world&apos;s mineral industry, distinctly in contrast with 1978 when estimated world crude mineral output value declined slightly and most phases of the industry&apos;s activity were somewhat curtailed. In 1979, most major mineral commodities recorded significant gains in output, with a substantial number achieving new record highs; details on trade levels for 1979 were not available, but increases over those of 1978 were expected on the basis of partial data. Consumption of most commodities edged higher; in some cases the higher demand levels were met largely through draw-downs of stocks accumulated in recent years, while in other cases notable output increases were required to meet demand. Actually, 1978 was not a bad year for all elements of the mineral industry if changes in output levels of the various commodities are considered as a measure of performance. There were far more individual commodities registering production increases between 1977 and 1978 than registered declines, but some of those reported as declining were relatively major commodities (bauxite, aluminum, copper and zinc were notable), Moreover, the upturn in productive activity in 1978 was not matched by increases in profits. However, 1979 was unquestionably a year of renewed expansion efforts, although some commodity areas, most notably the steel industry component, were still experiencing difficulties.

Jan 1, 1981

By Thomas Fraser

WHEN the Bureau of Mines initiated the program of large-scale research and development in the field of synthetic liquid fuels authorized in the Synthetic Liquid Fuels Act of April 5, 1044, the Coal Preparation Section was assigned the task of obtaining data on the preparation characteristics of the coal in large reserves that might be adaptable to use in this new industry. It is natural that, as the rapidly developing general research program brought about new concepts of raw-material quality, preferred geographical location, and the like, the orientation of coal-preparation investigations should have undergone some change. The first major assignment was the sampling and testing of a series of typical American coals deemed to he suitable for hydrogenation based on early research work conducted by the Bureau of Mines. This first series of tests has been completed and is reported in this paper.

Jan 1, 1950

By G. R. Fitterer, M. B. Royer

The application of manganese in iron and steel metallurgy is very inter¬ esting historically. In general, ancient- irons and steels contained virtu¬ ally no manganese, probably because the available iron ores contained■only small amounts of the manganese oxides. Occasionally, samples of ancient irons were found to have appreciable amounts of manganese, but their presence is considered accidental and dependent upon the ore available to craftsmen of that time. Two specimens of iron (139;— made in 500 A.D. contained .negligible quantities of manganese. A sample of steel which constituted the base of .the Khan Baba pillar in India was probably processed in 12p B. C. by the1 cementa¬ tion of wrought iron. This material; contained 0.02 percent manganese and 0.70 percent carbon (20) . One Damascus-steel sword forged some time between 11'60 ' and l400 A. D. was found to contain 0.1^-i percent manganese and 0.j6l percent carbon. The manganese content of this bla.de was much higher than that of any other material of this type which has been analysed. In every other instance the manganese content was below 0.02 percent. A cast steel manufactured by the East India. Co. in India in the early nineteenth century, under the name of Wootz steel, contained rather appreciable amounts of manganese. This material was made by melting and refining fairly high-manganese pig iron prepared from high-manganese ore. Heath (106), who was working at the Co. plant between 1S20 and 1S40, was convinced that the manganese content of the steel was the determining fa,ctor in its high quality. He learned of certain difficulties English steel manufacturers were having in making even fair-grade steel, and analyses of the material indicated low manganese contents. This convinced him that.if the use of manganese could be introduced in England its steel would be greatly benefited. In consequence, he moved to England and soon was producing certain grades of ferromanganese for use with the crucible process. He recommended addition of this metallic material to the ingot mold just before pouring. It was soon found that inferior brands of steel containing only traces of manganese could be greatly improved by such additions. All metallurgists of that time became convinced

May 1, 1934

By R. D. Leitch

"INTRODUCTION The character of mine drainage from areas of low pyritic coal3 and from average pyritic coal4 has been investigated, and to complete the study it seemed desirable to select a number of mines situated in high pyritic are as to determine whether or not this variation determines the relative acidity of drainage from mines operating in these characteristic coal fields. Advantage has been taken of some worked on in 1918 by Henry Leighton 5, then Professor of Economic Geology, University of Pittsburgh. He visited and has reported certain areas of high pyritic coal which we also visited during this study. Many of the mines were found to be idle in 1930 and a few were caved shut, apparently for several years. However, samples of the outflow from all mines visited were collected if possible and analyzed, and some general information was gathered for each mine. The map (fig. 1) shows the location of these areas as given by Leighton.ACKNOWLEDGMENTSThe information and assistance obtained from officials and others at the mines visited during this study are gratefully acknowledged, as well as the original suggestion from Dr. Glenn V. Brown of the State Sanitary Water Board who called attention to the desirability of such a study.Thanks are also especially due the coal laboratory of the United States Bureau of Mines, under the direction of H. M. Cooper, for the analyses and determination of sulphur forms in the large number of solid samples necessary to the work reported,This study has been carried on under the direction of R. R. Sayers, chief, health and safety branch, and W. P. Yant, supervising engineer, Pittsburgh Experiment Station, of the U. S. Bureau of Mines."

Jan 1, 1932

By E. H. Burroughs, M. J. Gavin

The references in the following compilation are selected chiefly from the literature of the years 1915-1920 , though a few of the more valuable standard works published before that period have necessarily been included . References to many articles have been omitted purposely , because the material covered by them is duplicated in publications included in the bibliography . It is manifestly impossible for the Bureau of Mines either to recommend or adversely criticize the statements of the various writers , particularly as to cost and profit estimates in articles referring to American shales , but it is hoped that the investigator will use caution in considering such statements , as it is well known that much of the literature on this subject has been published for promotion purposes and is therefore over- enthusiastic . Bearing this fact in mind , the reader should be able to judge for himself the reliability or usefulness of these articles .

Sep 1, 1921

By Byron S. Kutscher

This report summarizes the program to develop and construct an improved light-scattering dust monitor (ILSDM). This improved light-scattering dust monitor, which operates on the forward light scattering principle, provides instantaneous measurements of airborne dust concentrations in units of mg/m. The program was divided into two phases. Phase I involved the design of the ILSDM which was reviewed by the Bureau of Mines. Phase II included the fabrication of a prototype ILSDM based upon the design developed during Phase I. After completion, the ILSDM was delivered and demonstrated at the Bureau of Mines. A description of the final ILSDM design, operating instructions, maintenance instructions and recommendations for additional work are also included in this report.

Jan 1, 1980

By W. P. Huleatt, Jr. Traver, Jr. Hazen

"Vanadium and uranium occur widely distributed throughout western Colorado and eastern Utah, and a few deposits have been found in northeastern Arizona and northwestern. New Mexico. The area in which it occurs includes approximately 10,000 square miles and is generally referred to as the vanadium region of Colorado and Utah.The majority of the deposits consist of replacement bodies and impregnations of rare minerals in the lower Morrison formation of Jurassic age. The ore bodies are flat, with irregular margins, and most of them conform to the stratification.The ""rim rock"" topography of the region includes many steep-walled canyons and plateaus, which afford an abundance of outcrops that have been responsible for most of the discoveries of mineralized areas. Delimitation of ore bodies within the areas is accomplished most effectively by core drilling from the surface.The deposits were discovered in 1899 and from 1911 to 1923 wore worked extensively for radioactive uranium ores, principally carnotite.The discovery and marketing of the richer and more cheaply mined pitch-blende ores of the Belgian Congo left the Colorado-Utah deposits without economic importance as sources of radium and uranium, and the region became inactive in 1923. After a period of comparative inactivity, the rising demand of the alloy-steel industry for vanadium renewed interest in the deposits, which were known to contain that metal. By 1938, vanadium production in the area had achieved respectable proportions, and new impetus was given to it by the United States’ entry into World War II in December 1941. In 1942, new treatment plants for vanadium ores were completed in Monticello, Utah, and Durango, Colo. In order to meet the requirements of these and other plants in the region, it became necessary to open new vanadium mines and prepare old onus for production.In an effort to stimulate mining, the Metals Reserve Company initiated a stock-piling program and appointed the united states Vanadium Corporation, to act as its purchasing agent.The extra production was expected to come largely from small, independent operators whose limited funds did not permit them to maintain development and exploratory programs. Study of conditions made it apparent that extensive exploration would be necessary to sustain production, and accordingly the Bureau of Mines initiated an exploratory drilling project on a cooperative basis with the Geological Survey. The principal objects of the work were to enlarge the known ore reserves of the area and, if possible, discover new ones. The results have been gratifying in both respects."

Sep 1, 1946

By Herman W. Hill

This report summarizes research into the root causes of failures in mine power systems which impact safety and reliability. Abnormally low fault currents, due to arcing faults, self-excited systems, and fallen trolley wires are examined and quantified. The reliability of components which are critical for safety is studied, as well as reliability of components which are crucial to the mining pro cess. Failure rates are found through in-situ tests, accelerated life tests, studies of mine maintenance, and fault-tree analysis. Reliability data is used to predict fatalities and lost-time accidents through computer-aided fault-tree analysis. Analytical support tasks reported include the deriving of trailing-cable ampacities under cyclic loading, and the measurement of connected ground beds.

Jan 1, 1981

By F. D. Wang

This report presents a structural-mesh-generating computer program for the two-dimensional finite-clement method of mine structural analysis of single and multiple openings in nonhomogeneous rock mass. This program greatly reduces the amount of input data required and the chances of error which otherwise are large owing to the large amounts of data and the complex mesh involved. The program description, a user&apos;s guide, example problems, and program listing are included.

Jan 1, 1971