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By Albert W. Deurbrouck

The preparation characteristics of the coals of Buchanan County, Va., are described in this Bureau of Mines report. Twenty-one samples ,,,ere collected from 9 coalbeds in the county. Of these samples 13 were of metallurgical quality as received, and 8 required some upgrading to provide acceptable products. In general, the coals were of low to medium ash and sulfur content, and ranked as medium-to high-volatile bituminous. In 1963, production in the county was in excess of 13 million tons, of which 2.2 million tons were mechanically cleaned.

Jan 1, 1966

By Jr. Hazen

Relationships that may exist between assays and sample interval lengths when using unequal sample intervals in mine sampling have been investigated as part of the larger research problem of adapting statistical methods to the analysis of weighted average grades. The theoretical relationship between the amount of difference in the weighted and unweighted average grade of ore and the size of the correlation coefficient between assay value and sample interval length was found to be linear. Numerous examples of actual field sample and assay data, which have been obtained by using unequal sample intervals, are documented, and the differences between weighted and unweighted average grades of ore and the correlation coefficients between assays and sample interval lengths have been computed and plotted on graphs. Differences between these actual field data and the expected theoretical linear relationship are examined. It is hypothesized that the use of unequal sample intervals in mine sampling is, in fact, stratified sampling in a statistical context. The sampler establishes stratification by selecting unequal sample intervals on the basis of differences in lithology, changes in rock type, characteristics of mineralization, or differences in metal content. Statistically} methods currently used in mine sampling, involving unequal sample intervals, fail to consider differences in the inherent variances in grade of ore within the various strata established by using unequal sample intervals. Consequently the strata are sampled with different precision. This difference in precision of sampling between strata may account for much of the deviation between the plotted points representing actual field sampling data and the theoretical linear relationship between the amount of the difference between weighted and unweighted average grade of ore and the size of correlation coefficient between assays and sample interval lengths.

Jan 1, 1966

By K. K. Kelley

Synthetic fluorphlogopite mica (KMg3AlSi3010F2) is a relatively new product developed at the Norris (Tenn.) Station of the Bureau of Mines, Thermodynamic data have applications both in the production and use of this product, and the work described in this paper was undertaken to fill the need for such data. Measurements were made of the heat of formation at 298° K., the heat capacity between 50° and 298° K., the entropy at 298° K., and the heat-content and entropy increments between 298° K. and a maximum of 1,804° K. These basic data are combined to obtain heats and free energies of formation of the mica from the elements and from molecular constituents at temperatures ranging from 298° to 1,800° K. Minimum heat requirements to form melted mica from commonly used ingredients were calculated.

Jan 1, 1959

By M. R. Geer, H. F. Yancey

"INTRODUCTION With the advent of war in 1941, military operations in Alaska were enlarged on such a scale that the demand for coal in the Territory more than doubled. Coal was needed urgently for heating forts and other military establishments, for use on large construction projects, and for handling the greatly increased volume of traffic on the Alaska Railroad. -The additional tonnage required, estimated at perhaps 250,000 tons per year, probably could have been supplied by the United States, but shipping space between Pacific Coast ports and Alaska was already overburdened with military supplies and construction materials. Moreover, although of only secondary importance in wartime, the cost of coal shipped into the Territory is reported to have been as high as $40 per ton. The alternative to importing coal was, of course, to increase the Production of the Alaska mines.Production of coal in Alaska reached, 350,000 tons in 1944, or more than double the prewar' output. The responsibility for increasing coal production was assumed largely by the Army, A Coal Commission attached to the Alaska Department arranged financial assistance for some mining operations, aided the operators in producing equipment for mechanization, and provided most of the labor necessary to operate the mines. The Bureau of Mines contributed to the program in several ways. First, exploration by the Bureau in the Moose Creek district revealed a substantial tonnage of coal of better grade than any currently mined in the Territory, 4/ and drilling in the Broad Pass district, where a mine to supply coal for the army had been started, revealed that the reserves were far less than had been supposed; this operation was abandoned. Second, coal-preparation practices were studied, and recommendations for improvements made, at two of the operating mines at which the quality of the coal makes preparation a factor of vital importance. Some of the information obtained in these studies forms the basis for the present report."

Jan 1, 1946

By W. M. Traver

During World War II, the Bureau of Mines investigated a large number of ore deposits in the United States and Alaska in a search for domestic sources of strategic minerals. Deposits chosen for exploration included those expected to contain metals of importance in the successful prosecution of the war. This report describes exploration of a district of known antimony occurrence on Coyote or Antimony Creek near Antimony, Garfield County, Utah. A preliminary report by Paul T. Allsman, Chief of the Bureau's Salt Lake City branch made in August 1941, recommended further investigation, and proposed methods for performing the work. The project, begun in November 1941 and completed in January 1942, included trenching and sampling in four of the most promising parts of the area The Federal Geological Survey cooperated in the work by detailed mapping and assisted in the interpretation of geologic data.

Jan 1, 1949

By Oliver Bowles

"Simple systematic accounting that adequately records all transactions has long been regarded as essential to the welfare of any business enterprise. Some of the defects that detract from the prosperity of the slate industry are attributable to a lack of effectiveness in cost keeping. This condition has prompted the United States Bureau of Mines to make a detailed study of accounting methods for the slate industry, and to present for consideration a system of accounts, which it is believed would enable the industry to attain more economical management and operation if accepted by a fair proportion of its important units.The method of accounting presented herein has been worked out with the assistance of leading slate producers and the recommendation are tentative and are submitted in this form as a means of developing constructive criticism. Believing that cooperative effort in this, as in many other problems, will bring the most enduring benefits to the industry as a whole, the writer urges that the most earnest consideration be given to this vital problem now facing the slate industry.Grateful acknowledgment is made of the helpful assistance rendered by R. E. Eckert of the accounting firm of Eckert, Degan, and Palmer of Easton, Pa., in compiling the charts and the explanatory text. He has brought to this work a wide knowledge of accountancy, supplemented by a background of direct contact with the slate industry, and his presence at the various conferences has been of great advantage in clearing up difficulties. The National Slate Association sponsored the cost study and chiefly through the efforts of President W. H. Smith and Secretary W. S. Hays, has aided greatly in conducting it. Acknowledgment is also made of assistance rendered by William F. Marsh of the United States Bureau of Mines."

Nov 1, 1929

By E. M. Tignor

A research program to aid development of improved methods for increased production of petroleum from partly depleted reservoirs is a vital part of the Bureau of Mines effort to effect true conservation of that mineral resource. This report presents results of an investigation to identify the clay minerals within some Appalachian petroleum-reservoir sands, the effect of clay content on the fluid-flow behavior of those sands, and the use of brines in water-flooding operations. Permeability measurements using kerosine, calcium chloride brine, simulated oilfield brine, potassium chloride brine, sodium chloride brine, and distilled water were made on reservoir-rock cores. Clay fractions were separated from sand grains of disaggregated portions of each core sample, and the clay minerals were identified by the differential thermal analysis method. Relations of the permeability to various fluids were developed.

Jan 1, 1957

By O. C. Blade

This report on the properties of aviation gasolines and aviation jet fuels produced in the United States during 1954 was made under a co-operative agreement between the American Petroleum Institute and the Bureau of Mines of the United States Department of the Interior. Analytical data are presented for 101 samples of aviation gasoline. Data also are given for 30 samples of aviation jet fuel. The analyses were made on samples typical of the manufacturers I 1954 production in their laboratories and the results submitted to the Bureau of Mines for compilation. The products of 19 manufacturers of aviation gasolines and of 15 producers of aviation jet fuels are represented.

Jan 1, 1955

By D. H. Mullen, S. M. Runke, J. B. Cunningham

"SUMMARYThe coarse-grained granitic pegmatities of the United States have long been a source of many important industrial minerals, because of this, they have been studied intensively by geologists, mining engineers, and metallurgists. These studies have amassed a rather astounding array of published and unpublished information.Correlation of geological studies between individual pegmatites, as well as between major districts, has brought forth some semblance of order to the knowledge of the structure and Mineralogical composition of those highly complex and irregular deposits, making it possible to classify certain prgmatitites and pegmatitec zones into several groups of associated minerals; based upon the presence or absence of the minor minerals of beryllium and lithium. This classification or grouping of minerals, with the methods that have been developed for recovering certain of these minerals, makes possible a systematic approach to the winning of many of the industrially important minerals from pegmatite rock by a single integrated process.As the coarse-grained granitic pegmatites are composed primarily of,feldspar, quartz, and muscovite, the methods developed for separating and recovering them, as well as those methods developed for separating and recovering such minor minerals as spodumene and lepidolite, are important contributions to the over-all problem of pegmatite treatment. Some of these methods have been demonstrated in the laboratory only, whereas others have progressed beyond the laboratory stage arid are being employed in commercial operations.Recent laboratory investigations at Rapid City, employing both these early developments and the mineral groupings, have demonstrated that a single integrated process can recover muscovite, feldspar; and. quartz from the rejects of hand-sorting a typical muscovite-feldspar-quartz material. Employing a newly developed procedure for the flotation of beryl, the investigations have also demonstrated the possibility of recovering the beryl, in addition to muscovite, feldspar, and quartz, by an integrated process from a typical berylliferous pegmatitic material in which all of these minerals are present."

Dec 1, 1952

By David E. Siskind

The Bureau of Mines recorded particle accelerations in the mine roof produced by three types of explosives in the Pilot Knob Pellet Co. mine, Pilot Knob, Mo. Examined were the effectiveness of cube root, square root, and two-thirds power scaling in grouping the underground blast vibration data, and the effects of mine geometry, rock type, explosive type, and charge size on blast vibration levels. A propagation law for this mine was determined. The scaling factor of the square root of the charge weight was developed from previous Bureau studies of vibrations from quarry blasts, and in under-ground blasting both square root and cube root scaling were found applicable for scaling particle vibration data. The vibrations from the Pilot Knob blasts were best grouped by a square-root scaling factor. The empirical propagation equation AW1/2 = 76,250 (R/W1/2)-2.61 where A is the peak acceleration in g's, W is the charge weight in pounds, and R is the distance from the blast in feet, may be used to describe vibration amplitudes from charges fired with zero delay caps or with a single cap at Pilot Knob. Statistically significant differences were found in the vibration levels generated by the different explosives. The Power Primer (75-percent weight-strength ammonia gelatin dynamite) produced levels of vibration of 1.7 to 2.4 times those of AN-FO and slurry explosives; the latter two are approximately equal.

Jan 1, 1973

By Chas. F. Jackson

During the current business depression the Bureau of Mines has received many inquiries concerning placer mining, the prospects for men of small means to make wages by small-scale placer operations, the locations of placer deposits in the United States, methods of working placers on a small scale, and allied subjects. It has therefore seemed desirable to prepare a circular covering, in nontechnical language, the principal questions which have boon referred to the Bureau of Mines for answer. There are a number of bureau publications dealing with placer mining, most of which are now out of print, but which may be consulted in the larger libraries. Other articles on placer mining nave appeared from time to time in the technical press and several good textbooks have been written on the subject. A partial bibliography of this literature appears at the end of this paper. A recent pamphlet published by the Idaho Bureau of Mines and Geology to assist the prospector and inexperienced small operator has received wide and favorable attention and is recommended as a useful reference. In the present paper no attempt will be made to cover the subject of placer mining in a comprehensive manner, but discussion will be confined to elementary questions of particular interest to persons of limited experience.

Jan 1, 1932

By Arno C. Fieldner

Coal for coke production is fundamentally necessary for the manufacture of pig iron , and pig iron must be had for making steel - a vital element in our modern industrial economy . In both World Wars , special effort by Government and industry was required to meet the emergency of greatly increased demands . In the first World War , lack of coke - oven capacity , rather than lack of coking coals , was the principal problem ; but in the second World War both oven capacity and coking -coal mining capacity were pushed to the utmost . Because of inadequate supply , it became necessary to allocate a part of the production of these coals from other fuel use to coke production . This was done by the Solid Fuels Administration . These experiences raised a question , during and after the war, as to the nature and amount of the minable reserves of coking coal suitable for the manufacture of metallurgical coke ; and to what extent the lower -rank and lowergrade coals could be utilized by improving preparation and by appropriately blonding different coals . Obviously , much investigation and research are required to find answers to these questions . Somo work was done by Governmental and industrial agencies during the war , and , fortunately , more has been undertaken since the close of It is the purpose of this paper to review briefly our fuel reserves , with special reference to coking coal , and to discuss the problems of utiliz . ing progressively poorer coking coals as the reserves of high - quality coals approach depletion .

Mar 1, 1950

By John R. Zelonka

Models made by encasing strain-gage networks in epoxy are described and evaluated. With this technique relatively complex models can be constructed in which any number of gages can be located and alined precisely. Although the gages are an integral part of the model matrix, they create no important mechanical or thermal stresses. Model construction techniques and experimental data proved reproducible and reliable. In addition, the sGlution obtained with these models to the problem of the state of stress around a circular hole in a plate subject to a plane stress condition was in agreement with theoretical, photoelastic, and finite-element solutions.

Jan 1, 1970

By W. M. Dressel

A simple, reliable field test for beryllium in rocks has been developed by the Rolla Metallurgy Research Center of the Federal Bureau of Minas. A small portion of the pulverized rock is fused with a sodium carbonate-sodium hydroxide flux in a wire loop. The fused mass is dissolved in water, a few drops of quinizarin solution are added, and the solution is viewed under ultraviolet light. A pink-to-orange fluorescence reveals the presence of beryllium in a sample containing as little as 0.013 percent beryllium (0.26 percent beryl). INTRODUCTION New and potential uses for beryllium make necessary a more intensive search for this metal, which is so similar to aluminum in its chemical reactions that it is not separated from aluminum in ordinary chemical analyses. The principal ore mineral of beryllium is beryl, a beryllium-aluminum silicate, which contains only 5 percent beryllium. This mineral is so similar to quartz in appearance that it is not always possible to distinguish one from the other in the field. While the distinction may be made easily with a petrographic microscope, few prospectors have access to such an instrument, and fewer still know how to use it.

Jan 1, 1960

By E. R. Palowitch

A centrifugal float-and-sink test procedure has been developed by the Bureau of Mines to reduce the time for the gravimetric separation of coals finer than l4-mesh from as long as 24 hours to less than 1 hour. Comparative tests indicated that centrifuging a minus 14-mesh Pittsburgh-bed coal for 20 minutes at 1,500 revolutions per minute produced results that compared favorably with static float-and-sink test results. Standard deviations of the mean recovery and ash content of the float obtained centrifugally ranged from 1.31 and 0.04 percent, respectively, at 1.30 specific gravity to 0.21 and 0.05 percent, respectively, at 1.60 specific gravity. As in static separations, retreatment of the products separated at low specific gravities was required.

Jan 1, 1961

By J. E. Matta

The Bureau of Mines made laboratory absorption measurements on oil shale samples, which showed that the amount of methane absorbed is proportional to pressure and oil yield, and can be much larger than would be predicted based solely on porosity. Oil shale cores collected in the field were also measured for their gas content using the Bureau of Mines direct method. Cores taken from deep locations and far from outcrops yielded more gas than cores from shallower locations or at outcrops, when taking into account variations in oil yield, and all data indicate that oil shale mines that are both deep and far from an out-crop will emit low levels of methane gas.

Jan 1, 1977

By T. E. Gray

This report describes the preparation characteristics of the more significant coals in Dickenson County, Va. It is one in a series planned to determine which coals are suitable for the production of metallurgical coke either as mined or after beneficiation. Nearly 4 million tons of coal was produced in Dickenson County in 1955, of which approximately 2.7 million tons was cleaned mechanically in 5 cleaning plants. The Federal Geological Survey has estimated that nearly 1,300 million tons of measured and indicated coal reserves remained in the county as of January 1, 1951.

Jan 1, 1958

By Arthur L. Murray

"Oil-shale camps are peculiarly favored, in that before they are establishes it can be ascertained with a degree of certainty, that the life of the project is not limited. Unlike camps at metal mines, where the metal content of a given area is frequently an unknown quantity until after years of development, oil-shale camps should, from the outset, be planned and. built as permanent types of camps. Where this procedure is followed camps will be established which better serve the needs of the industry and the cost of their general care and upkeep will be less.Selection of camp or townsite.The site of the camp or town' whether on company property or not, should be selected with care. It should be separate if possible from the location of the plants of the company so as to be free from noise and fumes and so as to provide a change of environment for employees in going from their work to their homes.The principal features governing the site to be selected are as follows:Drainage. The general contour of the surrounding country should be such that drainage is away from the site. The camp or town should, if practical, be situated on higher ground than that in its immediate vicinity.Soil. The nature of the soil on which the camp or town is located may bear a decided relation to health. A porous, well underdrained top soil of at least four feet in depth insures dryness and facilities the placing of foundations and the laying of water mains and sewer pipes. Such a soil also is an advantage in growing trees, shrubs and grass plots, which are a decided adjunct to making the community attractive.Enviroment. The contiguous territory should afford no unwholesome sur¬roundings such as swamps Or accumulations of stagnant water.General Considerations. The water supply to be provided and the method of disposal of wastes influence to a certain extent the location of the camp or town-site. The means of supplying water, whether by gravity or by pupping, and the disposal of sewage, whether by outfall, system, sewage disposal system through septic tanks, broad irrigation or filter beds, or cesspools will govern the location of the site topographically in relation to source of water and point of disposal of sewage.* This article was prepared as part of the paper ""Use and Supply of Water for the Oil-Shale Industry"" by J. J. Jakowsky, to be published by the Department of Metallurgical Research, University of Utah, in cooperation with the United States Bureau of Mines."

Jul 1, 1921

By R. T. Sorensen

Research and testing in a small scale equivalent of a commercial flota-tion plant was completed on four low-grade, iron-bearing materials from the western Mesabi range. Closed circuit-flotation of calcium-activated silica with fatty acid collector developed data for comparison with the batch process and highlighted problems not evident from previous bench testing. The four ore samples contained from 27 to 39 percent Fe and were equally represented by nonmagnetic taconite and semitaconite type materials. Iron concentrates containing 6.0 percent, or less, SiO2 were made 5, all four samples. Of the two material types, the semitaconite was the ore amenable to treatment, yielding iron recoveries of about 90 percent as cc pared with 70 to 80 percent for the other. Pilot plant tests showed that concentrate grade made in batch tests could be duplicated in the closed circuit and demonstrated that the amount of recoverable middling iron varied considerably between ore samples. The continuous tests also showed that water temperature strongly influenced results in the treatment of one ore but apparently was of indifferent consequence in another. Progress in thickening and filtration of flotation concentrates was made through introduction of tapioca flour to serve the dual role of iron mineral depressant and flocculant.

Jan 1, 1966

By William L. Crentz

Floyd County, KY., contains sizable deposits of high volatile bituminous coal. Some of the coals have been blended with higher-rank coals and used in the manufacture of high-quality metallurgical coke. The Upper Elkhorn No. 3, Upper Elkhorn No. 2, and Upper Elkhorn No. 1 beds produce the bulk of the present output in the county and contain the main known reserves of coal. Little information is available concerning the quality and extent of the deposits underlying the Upper Elkhorn No. 1 bed, although small operations in the past have worked a bed that is reported to be; the Lower Elkhorn. Undoubtedly, these lower beds occur in Floyd County, but depth Will preclude their development into a major source of fuel as long as large deposits of more-accessible coal are available. More is known of the occurrence of the beds above the Upper Elkhorn No. 3 owing to sporadic mining ventures in the upper measures. Many of the coal samples from beds above the Upper Elkhown No. 3. were collected in mines that had been abandoned. Almost all of the present production of Floyd County coal is taken from the Upper Elkhorn beds, and it is unlikely that their dominant position as coal producers will be challenged in the near future. Table 1 shows the coal production of the county by beds, during 1950.

Jan 1, 1952