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By Robert H. Ridgway

Scrap iron and steel attracted attention during 1937 because of the unprecedented exports and the concomitant agitation in some quarters to prohibit the exportation of this essential raw material except on license by the President. This report does not attempt to analyze the statistics given in the light of the controversy over the limitation of scrap exports, but it is believed that students of this problem will find many essential basic data in the various tables presented herein. This paper presents the results of the third in the series of annual canvasses on the consumption of ferrous scrap and pig iron in the United States. The study was inaugurated in 1935 by the Bureau of Mines in response to requests from trade organizations and others for detailed

Jan 1, 1938

By Almon F. Robertson

"INTRODUCTION AND SUMMARYThis is one of a series of reports describing investigations within the Missouri River Basin in Montana conducted by mining engineers of the Bureau of Mines, Minerals Division, Region II. The primary purpose of these investigations is to provide basic information to agencies of the Department of Interior and others concerned with the planning of power and other water developments in the basin. This report contains only such factual data as have been authorized for public distribution. Special precautions have been taken not to reveal any information or data that are considered confidential.The field investigations for this report were made during the summer of 1949. Virtually all known metallic mineral deposits in the county and same nonmetallic (industrial) mineral deposits were investigated. Most of the mines and prospects have been inactive for many years. The old underground workings generally are only partly accessible; many are entirely inaccessible. Most of the mining claims were located many years ago, and a considerable number were patented. Many claims were abandoned; others were relocated. Nimes and ownerships often have changed. Because of such conditions, much of the information on most of the mines and prospects necessarily has been obtained from available Federal and State publications, private geologists' and engineers' reports, and from owners and local residents.Metal mining in Cascade County, Mont., has been confined mainly to the silver-lead-zinc deposits in the Montana (Neihart) and Barker districts in the southeastern part of the county. The Neihart district has yielded by far the greater part of the county's metal output. The mines generally have been operated intermittently, largely because of fluctuating or low silver and base metal prices."

Feb 1, 1951

By Harry V. Makar

As part of a continuing research program for conserving domestic mineral resources, the Bureau of Mines is investigating new and improved scrap identification techniques to improve sorted mixed scrap purity. This report focuses on various classes of wrought and cast copper alloys produced with recycled scrap. Based on a survey of the literature, principal alloys, such as the brasses and bronzes, are examined with respect to impurity elements and their effects on metallurgical behavior. Effects of elements such as lead, antimony, iron, chromium, and aluminum are discussed. The metallurgical effects described include hot shortness, fire cracking, and undesirable phase transformations.

Jan 1, 1985

By R. D. Leitch

"INTRODUCTION The general program of the investigation of coal mine drainage which the Bureau of Mines is making includes, among its many phases and objectives, a study of the fate of the acid, content of drainage after it enters natural streams, and the effect of seasonal variations on the degree of contamination of streams. Opportunity for studying these under comparatively normal conditions and variations can readily be found, but there is only a chance opportunity for studying than under extreme conditions. The unusual drought that prevailed during the summer of 1930, however, created a condition of low water favorable to a study of one of the extremes.This report gives the results of an investigation of Bennett Branch of Sinnemahoning Creek, Pa., made under this condition.ACKNOWLEDGMENTSThis work was conducted under the direction, and with the advice, of Dr. R. R. Sayers, chief, Health and. Safety Branch, and of W. p. Yant, supervising engineer, Pittsburgh Experiment Station.DESCRIPTION OF BENNETT BRANCHBennett Branch, as shown in Figure 1, is a tributary to Sinnemahoning Creek. Its source is in Huston Township, northwestern Clearfield. County, from which it flows in a general northeasterly direction through Elk County, thenceeasterly in Cameron County to Sinnoning Creek at Driftwood. The total length is about 37 miles. There are nine towns along the stream that have an average population of about 350. There is no industrial pollution other that from coal mines and very little. domestic, pollution."

Jul 1, 1931

By A. Matzick

In its work under the Synthetic Liquid Fuels Program the Bureau of Mines has developed on a 6-ton-a-day-pilot-plant scale a continuous, gravity-feed retort far distilling oil from oil shale. The development work covered by this report was done from January 27, 1950, to January 26, 1952, at the ail-Shale Experiment Station near Rifle, Colo. Over 300 pilot-plant tests were made during the investigation. The basic retort developed has been named the Gas-Combustion retort. In this process, part of the heat for retorting of the shale is generated by burning recycled product gas in a combustion zone within the descending shale bad in the retort. Additional heat is supplied by combustion of the carbonaceous residue remaining in the spent shale after the oil has been distilled. Air for combustion is admitted through an air distributor in the center of the bed at about the mid-point of the retort. Hot gas rising from the combustion zone heats countercurrently the descending raw shale and liberated shale oil by pyrolysis of the shale. After passing through and exchanging heat with the incoming raw shale, the oil is condensed as a fog or mist in the gas, which is withdrawn at the tip of the retort. The cool gas is then piped to an oil-recovery system where the oil is separated from the gas in centrifugal separators or other types of mechanical or electrostatic separators. The hot, spent shale below the combustion zone is cooled by heat exchange with recycle gas, which is a portion of the effluent gas from the oil-recovery system.

Jan 1, 1955

By W. D. Mcmillan

Preliminary examination of the north-central Kansas clay deposits was made by the junior author during March 1943. He was accompanied by Norman Plummer, ceramist of the State Geological Survey of Kansas. Three areas Nacre selected for further investigation. Detailed field investigation by the Bureau, consisting of hand auger drilling, trenching, anti. test pitting to obtain representative samples of the clays was carried on from April to June 1943. Field .work was under the direction of Edgar B. Butte and Richard L. Schumacher, former Bureau of Mines engineers. The samples taken were analyzed at the Bureau of Mines laboratory at Rolla, Mo. Factual data obtained from the field investigation and laboratory work are set forth in this report.

Jan 1, 1948

By E. R. Palowitch

Coal wasted with mine refuse represents losses in overall recovery of merchantable coal to the mine operator and a concomitant reduction in domestic reserves of available coal. Fraser, Kelley, and Graham3/ in studying the available coal in mine refuse in the Pittsburgh district of western Pennsylvania have estimated that at least 1 ton of mine refuse is produced for each 10 tons of merchantable coal and that 20 percent of this mine refuse might be recovered as salable coal by mechanical cleaning. SUMMARY This investigation dealt with the mechanical recovery of coal from wine refuse by a dense-medium washery employing pulverized mine rock as the dense medium and operating at a rate of 175 tons per hour. Two types of mint refuse were tested: Freshly mined and that .which had been mined 2 years before and piled on a waste dump.

Jan 1, 1955

By Robert Lee Stahl

Comprehensive field tests were made by the Bureau of Mines at the Schwartzwalder mine near Golden, Colo., to determine whether surface geophysical techniques could be used to detect and delineate faults in uranium deposits. The tests included seismic refraction, magnetometer, electrical resistivity, airborne infrared thermal scanning, and airborne photography. Of the several geophysical techniques tested in the field, horizontal resistivity profiling with electrode spacings in the range of 10 to 15 feet was most diagnostic of faults. The method is quick, inexpensive, and accurate and can be easily used by mining company personnel to detect and delineate faults.

Jan 1, 1974

By Richard F. Link, George S. Koch

Through the use of statistical methods, estimates of metal content and tonnage of an ore body made by using data from 18 diamond-drill holes are compared with actual values established with data from 1,829 drift samples. The reliability of the estimates made from the drill holes is assessed in several ways. The relationship of metal content (assay-width product) to grade is explained. It is concluded that useful estimates can be made from 18 drill holes provided that reasonable assumptions are made and certain risks accepted. The ore body investigated is the Don Tomas vein of the Frisco mine, San Francisco del Oro, Chihuahua, Mexico.

Jan 1, 1964

By G. W. Jones

An important activity of the Bureau of Mines is the promotion of safety in mining and industry. As a part of this program, the Bureau determines the explosion hazards of combustible gases, vapors, and solids and investigates means of controlling and preventing explosions. The limits of inflammability (explosive limits) of combustibles are not only of theoretical but also of practical importance, because many industries at one time or another contend with explosive mixtures of combustible gases or vapors in their manufacturing processes. At present many new organic compounds are being manufactured, transported, and used in huge quantities which a few years ago were only laboratory curiosities.

Jan 1, 1941

By Robert W. Waytulonis

The mining regulations of all 50 States were reviewed by the Bureau of Mines, and those parts pertaining to the use of internal combustion (IC) engines (particularly diesel engines) in underground mines or confined spaces were extracted. Also extracted were subjects associated with the use of IC engines; for example, storage and handling of flammable liquids, maintenance, and ventilation requirements. As the laws now stand, 29 States have specific regulations that affect the operation of diesel engines in underground coal and/or metal and nonmetal mines. The other States have no regulations because either they have no mining activities or they defer to Federal regulations. Six states have regulations expressly prohibiting the use of diesels in underground coal mines. Specific contacts (addresses and phone numbers) precede each State's regulations to facilitate inquiries about regulation revisions and interpretation.

Jan 1, 1981

By Harmon E. Keyes

Many organizations, including the Bureau of Mines, have made intensive studies of the application of leaching methods to relatively small low-grade disseminated deposits of copper ores, containing both oxide and sulphide minerals. One of the principal difficulties has been to obtain a solvent that could be made at a low cost and would effectively dissolve the copper minerals. Another drawback has been the high initial cost of a plant and the refined type of mechanism ordinarily required by standard practice for carrying out the leaching cycle. The Bureau of Mines has attempted to develop a cheap and efficient solvent that would especially meet the requirements of smaller plants. (See Bibliography.) It has been known that dilute ferric sulphate-sulphuric acid solution is an excellent solvent for most copper minerals, such as chalcocite, bornite, and oxidized forms, but not for chalcopyrite and certain silicates. A method of producing this solution from sulphurous products and waste liquors was developed by the bureau and tried successfully on a test-plant scale at the Southwest Experiment Station in cooperation with the department of mining and metallurgy, University of Arizona, Tucson, Ariz. However, this work did not involve the actual leaching of ores with the solutions thus produced or the cyclic use of the iron solutions in the regenerator cell. Except for certain laboratory tests, in which known impurities were added, no data were available to show the effect on regeneration if accumulations of impurities were built up in the leaching circuit.

Jan 1, 1930

By Robert W. Ageton

The Bureau of Mines investigated the in situ vertical component of the rock stress in the rib of the haulage drift on the 6100-level of the Star mine, Burke, Idaho, using the flatjack and borehole deformation methods. The estimate of the vertical component of stress about 2 feet into the rib at a station along the haulage drift on the 6100-level of the Star mine by the flatjack method is approximately 5,875 psi, whereas the borehole deformation procedure at this station yielded a value of 5,500 psi for the same depth into the rib. The test zone is approximately 5,625 feet below the surface.No attempt was made to extrapolate stress estimates beyond the depth of the flatjack installation.

Jan 1, 1967

By Michael S. Miller

The U.S. Bureau of Mines (USBM) conducted mineral investigations in the 1,227,000-acre Emigrant Trail study area of Nevada during 1992. During the USBM investigation of 25 areas of development interest, 190 mineral localities were identified and 260 rock and 50 alluvial samples were taken. At least 0.5 million troy ounces of gold, 2.3 million troy ounces of silver, 3.3 million pounds of copper, 10.9 million pounds of lead, 2.4 million pounds of zinc, 500 tons of alunite, 40,000 tons of sulfur, 9,000 pounds of mercury, and 21,000 pounds of tin have been mined from the area and vicinity. Adjacent to the study area, gold is being mined at large, open-pit gold mines, the Hog Ranch and Hycroft Resources, Inc., Sulphur mines, and new production is planned at the Rosebud LAC/Equinox. Hog Ranch mine is nearing depletion, but resources of more than 0.5 million troy ounces of gold and about 5 million ounces of silver are estimated for the Rosebud LAC/Equinox project and more than 0.4 million ounces of gold for the Hycroft Resources, Inc., Sulphur mine. Significant investigations are occurring at SP Ridge and other sites near Scossa and at the Dan claims in the Southern Calico Mountains. Precious opal, placer gold, and geothermal energy resources occur in the study area and vicinity.

Jan 1, 1993

By M. M. Tilman

As part of ongoing research to improve mine safety, the Bureau of Mines conducted research on the corrosion of friction rock stabilizer steels in five Missouri lead and iron mine waters. Electrochemical corrosion tests, including evaluation of pitting tendency, were performed on two types of high-strength, low-alloy (HSLA) steels and galvanized steel in four Missouri lead mine waters and one Missouri iron mine water. The tests were conducted at in-mine water temperatures in both air-saturated and deaerated waters. Static, weight-loss corrosion tests were also conducted on HSLA steel specimens in the five Missouri mine waters for 2,900-h duration at average in-mine water temperatures and air-dissolved oxygen contents of 6 to 7 ppm. Corrosion rates determined by the weight-loss tests were roughly comparable with rates determined electrochemically in deaerated waters containing 0.3 to 0.5 ppm dissolved oxygen content. Passivation of specimen (nongalvanized) surfaces in air-saturated waters resulted in very low electrochemically deter- mined corrosion rates. Pitting-tendency was generally higher for both HSLA steels in air-saturated waters than in deaerated waters. Galvanized steel generally exhibited higher tendency to pitting in the deaerated waters than in the aerated mine waters.

Jan 1, 1985

By Forrest T. Moyer

THE injury data and experience in this bulletin are presented in three general sections. The first section contains general and detailed data relating to 1948 injury experience in bituminous-coal and Pennsylvania anthracite mines, separately and combined into totals for all coal mines. The related employment, worktime, production, and productivity data are given in each breakdown of the statistical data. Tables 1 through 22 constitute a subsection and present statistics on number of injuries, frequency and severity rates, average severity, detailed and major causes of injuries, injury records of the coal-producing States, distribution of injuries by part of body, and distribution of injuries by days of disability. Tables 23 through 45, the second subsection, present injury experience in bituminous-coal mines by various selected factors of physical or operating conditions that ma contribute to the occurrence of injuries. The degree of mechanical loading, productivity, size of mine by number of men working and by tonnage mined, thickness of bed, length of shift, number of shifts, type of cap lamps, rating of mine as gassy or nongassy, type of ventilation, and combinations of these factors influencing mine safety are presented in this group of tables. Similar data on Pennsylvania anthracite mines are listed in tables 46 through 63, which comprise the third subsection. The second section of the report contains the generalized annual injury records of bituminous-coal, Pennsylvania anthracite, and all coal mines from the earliest available data through 1948. Tables 64 through 97 list the number of fatal and nonfatal injuries, injury rates, and causes of injuries on an industry basis, the long-term injury records of each coal-producing State, and the related employment, worktime, and production data.

Jan 1, 1952

By T. A. Henrie

A technique was devised for measuring the rate of chemical reactions between reactive metals and molten-salt mixtures at high temperatures. The rate of the heterogeneous reaction between high-purity titanium metal and titanium trichloride in molten sodium chloride was determined. The reaction is surface-controlled, and the heat of activation is 8.29 kilocalories per mole TiC13. An active site or reaction nuclei is created by adsorbing a TiC13 molecule at the metal surface. Reaction of the second TiC13 species forms an activated complex that decomposes into three TiC12 molecules.

Jan 1, 1963

By M. A. Elliott

Diesel-powered haulage equipment has recently been tested and approved for permissibility by the Bureau of Mines for use in mining in the United States. Achievement of this advance in safety involved extensive studies, both in the testing station (2, 3, 20, 21, 22, 23, 24, 25, 26, 27)3/ and in the field 1, 4, 13, 30), of the operating characteristics of diesel engines in relation to the toe of such engines underground. The results of these studies formed the basis for establishing the requirements that should be met by diesel-powered haulage equipment approved for permissibility. Considerable interest has been manifested in the development of diesel-powered haulage equipment fur mines. The purpose of this paper is to retrace briefly the course of this development and to answer such questions as: What is the history of the use of diesel engines underground? Why has the Bureau of Mines been interested in the development of diesel-powered haulage equipment for use in mines?

Jan 1, 1953

By B. W. Dunning

The Bureau of Mines investigated the concentration and distribution of precious metals in the various fractions produced from mechanical processing of obsolete military electronic scrap. Whole avionic units, printed circuit cards, and electrical connectors were processed and analyzed. Materials recovered included baghouse lights, wire bundles, mag-netics, and metal concentrates from eddy-current and high-tension sepa-ration. Higher value fractions were processed by a commercial toll refiner for recovery of gold and silver. Lower value fractions were analyzed by the Bureau. Three fractions, the lights, wire bundles, and metallics from high-tension separation, contained most of the precious metals. Depending on the type of scrap feed, these fractions represented 34 to 60 pct of the original sample weight. Collectively, they represented 68 to 97 pct and 75 to 98 pct of the contained gold and silver, respectively.

Jan 1, 1983

By S. J. Aresco

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analyses. To these, when required, are added the ash-softening temperature, the free-swelling index, and the Hardgrove grindablity index. Under most of these specification contracts the bidders guarantee the quality of the coal, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled in accordance with instructions3 issued by the Bureau of Mines; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor; if it is not, a price adjustment is made. Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous of coal as delivered is a check on the practical results obtained in the coal.

Jan 1, 1967