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By B. J. Moore

This publication contains analyses and related source data for 310 natural gas samples from wells and pipelines in 16 States. All of the samples were obtained and analyzed during calendar year 1978 as a part of Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted in the United States by the Bureau of Mines since 1917. In late 1965, the survey was expanded to include foreign gasfields. The analyses published herein were made by mass spectrometer and a special helium analysis appara¬tus, which are described in Bureau of Mines Bulletins 4862/ and 576.3/ The results of the investigation of the occurrences of helium are published annually to make the information available as soon as possible to the gas industry and the public in general. Twenty previous publications have presented the results of 11,573 gas analyses made prior to 197R. The first three, Bulletins 486,4/ 576,5/ and 617,6/ contain analyses and related source data on 5,218 gas samples collected from 1917 through 1960. The other 17

Jan 1, 1979

By Howard M. Stainer

Published X-ray mass absorption coefficients were compiled and tabulated. These coefficients are required for various X-ray analytical techniques. Values obtained from 28 authors are listed for 87 elements with both experimental and calculated points included; the wavelengths range from 4.01 to 68 A. Representative graphs are presented for six elements (lithium, nitrogen, iron, silver, holmium, and uranium. A 37-item supplementary bibliography is also included.

Jan 1, 1963

By Howard M. Stainer

Published X-ray mass absorption coefficients were compiled and tabulated. These coefficients are required for various X-ray analytical techniques. Values obtained from 28 authors are listed for 87 elements with both experimental and calculated points included; the wavelengths range from ~0.01 to 68 A. Representative graphs are presented for six elements (lithium, nitrogen, iron, silver, holmium, and uranium. A 37-item supplementary bibliography is also included.

Jan 1, 1963

By Harry W. Campbell

A mineral survey conducted by the U.S. Bureau of Mines in 1984 identified no mineral resources or prospects with mineral development potential in the Pit River Canyon Wilderness Study Area (WSA). Basalt suitable for aggregate and fill is in the WSA but rock of this nature is abundant in the region and closer to potential markets.

Jan 1, 1984

By Warren D. Longwill

All known resources within the four proposed RARE II additions to the Yolla Bolly-Middle Eel Wilderness in northwestern California occur in the Gig Butte-Shinbone study area (fig. 1). No mineral resources are Figure 1.--NEAR HERE. known in the East Fork, Murphy blade, or Wilderness Contiguous units. About 2,400 tons (2,177 t) of subeconomic manganese resources averaging 9.5 percent manganese have been estimated at the Blue Jay Mine in the Big Butte-Shinbone unit. In addition about 9,700 tons (8,793 t) of subeconomic chromium-nickel-cobalt resources in thin laterite soil at the Grubstake Prospect contain about 1.27 percent chromium oxide, 0.45 percent nickel, and 0.03 percent cobalt. Adjacent Ultramafic rock outcrops have pods averaging 2.5 percent chromium oxide (Cr203); one pod contains about 40 tons (36 t) of indicated subeconomic resources.

Jan 1, 1981

By C. Travis Anderson

"A recent critical study by Ralston3 of the iron system points out the importance of and necessity for work upon the preparation of ferrous oxide. Not only are ferrous oxide samples desired for determination of the important physical and chemical properties, such as specific heats and heats of formation, bat also information on the stability and behavior of this material is of considerable technical importance. Related. problems where the properties of Fe0 are important have to do with desulphurization of iron, the formation and occurrence of magnetite in copper smelter slags, and sulphur elimination in copperFerrous oxide also has valuable catalytic properties, as is demonstrated in nitrogen fixation.Pure ferrous oxide has never been prepared in quantities large enough to furnish adequate physical and chemical data on its properties. Only two or three experiments4 have produced a fraction of a gram in a state approximating purity and have collected evidence that has been sufficient proof of their having done so. Ferrous oxide is stable only above about 570°C., and below that splits into magnetite and iron according to the reactionUp to about 1920, those who had endeavored to prepare FeO made no provision for rapid chilling, so that although their product. may have had the proper iron oxygen ratio for FeO, in reality it-probably did not consist of pure FeO. The above reaction is reversible; above 570oC. magnetite and iron are supposed to recombine almost completely, and if so, should constitute a direct and easy method of preparation. The data, however, were somewhat conflicting, and the extent to which the reaction goes in either direction needed checking. Preliminary experiments on the interaction of molten Fe304 with solid Fe gave Fe0 of about 85 per cent purity, corresponding to. the approximate purity obtained by some previous investigators. The present work is concerned chiefly with the results cf repeated interaction between partly reduced magnetite and iron, and the calculations which may be made from such results. Repeated treatments are necessary, because molten impure ferrous oxide and iron can not be kept in contact for more than short periods of time."

Oct 1, 1928

By J. R. Thoenen

In the summer of 1937 the authors began a series of time studies of the various processes employed in' the production of crushed stone. These studies, made at quarries situated in the eastern and southeastern parts of the United States, have not been completed, but to make results available to the industry as early as possible, it was decided to publish summaries of the studies made to January 1, 1939, as a series of progress reports. The first of these dealt with power-shovel loading and was issued as Report of Investigations 3461 in September 1939. The second, issued in September 1939 as Report of Investigations 3467, dealt with quarry haulage. The present report discusses analyses of time studies of primary drilling at the same group of quarries. OBJECT Or STUDY Pressure of business problems frequently requires the entire attention of quarry management, and in consequence internal plant economies often are neglected. Also, operating officials absorbed in their local problems are prone to overlook possible economies that would attract attention immediately were they critically examining another plant. The authors felt that technical studies at a number of plants, made by impartial engineers, might disclose opportunities to reduce costs or improve efficiency in internal plant processes.

Jan 1, 1940

By D. D. Bush

Based on the results of this study, the underhand cut and fill stoping method, with mass destressing, is an effective method for controlling rock bursts and falls of ground for deep mining in the Coeur d'Alene Mining District. The procedure can be utilized to pull highly stressed pillars by converting from conventional overhand stoping methods or used as a primary recovery system. During the demonstration, only one minor rock burst occurred, with no injuries. The system facilitates accurate placement of vertical boreholes for effective mass destressing. Each mining cut is filled with cemented sandfill overlying a timbered mat that forms the back for the succeeding cut. For this demonstration, a cemented fill was mixed on the surface and piped to the stone. Costs for pillar recovery by this method are comparable and are considered cost effective over conventionally timbered overhand mining as a pillar recovery method.

Jan 1, 1982

By James E. Bell

Quartz crystals occur on a farm in the vicinity of Laurel Fork, Carroll County, Va., in abundance over a large area, This has been known for several years, but no work had been clone, up to the Bureau of Mines examination in 1943, to determine the amount of crystalline quartz of usable quality. Field exploration was undertaken throughout the month of June 1943.

Jan 1, 1950

By Paul S. Goodman

Volume II The purpose of this study is to explain reasons for the productivity differences in mining crews. The literature on group productivity is examined. Then a new approach to estimating productivity differences is proposed and estimated across seven different mines. The results indicate a fairly robust model in terms of explanatory power. Recommendations on how the model can be used as a managerial tool are presented.

Jan 1, 1985

By Robert J. Willard

This chapter includes tables for 1982 that were not available in time for publication of the 1982 Minerals Yearbook, but does not include corresponding tables for 1983. The value of raw nonfuel minerals produced in the United States during 1988 was estimated at $21.1 billion, an increase of $1.5 billion over the value for 1982. This is a reversal of last year's downturn in value from that of 1981, which was the only decrease noted since 1971; hence, an overall trend of increasing values has been maintained for 12 years, except for 1982. Although the reversal is a basis for cautious economic optimism, it is tempered by continued problems in the domestic mining industry: inadequate funds for capital investment and competition with other countries that have lower production costs. Output of metal commodities in 1983 increased for 8 out of 21 metals, and metal values, in general, increased for 9 of the metals. Output of nonmetal commodities was mixed, with 24 nonmetals showing increases, 20 showing decreases, and 2 unchanged. Nonmetal values were also mixed in 1982: 25 showed increases, 20 declined, and 1 was unchanged. Improvements in the international metals market have not been forthcoming because of the continued depressed prices for major metals. Governments in foreign producing countries have been concerned with maintaining employment and continuing foreign exchange flows through mineral exports. Consequently, the excess of supply in the face of shrinking demand brought downward pressure on metal prices in general, except for the precious metals. On the domestic front, this situation means U.S. mining companies must become even more cost efficient. The major trend in the mining industry in 1983 was to cut costs further, reduce or stabilize total production, reduce outlays for major capital equipment, modify existing systems and equipment, and streamline operations. Most of the accomplishments reported herein reflect this trend.

Jan 1, 1984

By Martin H. Rogoff

This publication combines a critical review of the literature on the microbiology of coal with an introduction to those areas of microbiology related to studies of coal as a biological material. The attack on coal by microorganisms as yet remains doubtful. Only the low-rank coals contain an indigenous microbial flora, and even these organisms are not peculiar to coal, but are common soil and water forms. No experimental data have as yet been presented, either in the literature or in the present work, which unequivocally demonstrate the oxidation of coal by microorganisms. Reasons for the resistance of coal to such attack, including insolubility, physicochemical structure, steric hindrance of enzyme action, and the presence of antibiotic materials in coal are discussed. Microorganisms do attack large aromatic molecules and the mode of oxidation of aromatic ring systems by bacteria is presented. Well-defined pathways are known for the oxidation of polycyclic compounds with one to three rings, and these paths with their key intermediates are described and related to the possible oxidation of coal.

Jan 1, 1962

By W. P. Yant

A previous report of the Bureau of Mines dealt with the toxicity of dichlorodifluoromethane5, a new refrigerant that has a remarkably low toxicity. Continued research by the Prigidaire Corporation6 and toxicological experiments performed in the Laboratory of Applied Physiology of the University of Cincinnati7 revealed another organic fluoride, dichlorotetrafluoroethane, whose toxicity also appeared to be of a very low order and whose physical-and chemical properties make it suitable for refrigeration purposes. In addition to low toxicity, safety in its use is further enhanced by its physical properties, which permit the design of equipment that operates at comparatively low pressures and hence mitigates the dangers and problems of leakage. The investigation described in this report was performed by the Bureau of Mines at the request and with the cooperation of the Frigidaire Corporation.

Jan 1, 1932

By R. Ward Stahl

The underground junction or intersection is analogous to the doorway or window in a building in that the continuous wall or support for the overhead structure has been weakened by making the opening. Some type of bridge or support seems necessary to prevent roof sag and possibly eventual failure at this point, although frequently it appears that little is done until a fatal accident induces action. The intersection generally represents less than 15 percent of the exposed roof area. As a result of recent multiple fatalities, some of which occurred at or near intersections, the Bureau of Mines was asked to examine the junction-support problem more thoroughly and to report its findings. A national survey of the junction-support systems in use has been made by correspondence, and the local area has been canvassed rather thoroughly to determine just what and how much is being done.

Jan 1, 1962

By Frank S. Wartman

"The experimental flotation work described in this paper was undertaken to test the conclusions derived from a previous microscopic and chemical study of several samples of converter slag. That study3 resulted in the conclusion that approximately 90 per cent of the copper content of a converter slag wad in either the sulphide or metallic form, and that if the slag were cooled slowly the copper-bearing material would be in particles of such size that they would be freed from silicate and magnetite grains by grinding the slag to pass a 150-mesh sieve. If this were true, it should be possible to separate the copper-bearing grains from slowly cooled, converter slag by the flotation process.Many attempts, of which the author has seen no published account, have been made to treat slags, especially converter slags, by flotation. In every case these trials have been made with chilled slags, in which, as shown in the preceding report, the copper-bearing material is top finely disseminated, to be freed by any reasonable degree of grinding.The flotation tests described in this paper have shown that it is possible to recover by flotation about 30 per cent of the copper content of a converter slag containing 3 per cent copper and to obtain flotation concentrates which have a copper content of 35 per cent.Acknowledgment is made to G. L. Oldright, supervising engineer of the section of nonferrous metallurgy, U. S. Bureau of Mines, for valuable assistance and direction; to W. A. Sloan for chemical analyses; and to Alfred P. Towne for assistance in experimental manipulation."

Apr 1, 1931

By Berenice B. Mitchell

THE STATISTICAL tables in this chapter present, country by country, the mineral production of the world in 1949-50. The figures are on a mine basis, unless otherwise indicated, except for cement, coke, and steel, which are measured at the processing plant. The tables are essentially a retabulation, by countries, of the 53 commodity world tables appearing in the various chapters of this volume. For lack of comprehensive information, data for the following minerals are excluded: Andalusite, aplite, asphalt, boron, bromine, calcite (optical), calcium chloride (natural), carbon dioxide, clay, columbium (niobium), diatomite (kieselguhr), dumortierite, emery, garnet (abrasive), gem stones (other than diamonds), germanium, greensand, grindstones, helium, indium, iodine, kyanite, lithium, magnesium compounds (other than magnesite), meerschaum, mineral pigments, monazite, natural gas, natural gasoline, oil shale, olivine, perlite, pumice, quartz crystal, radium, sand and gravel, selenium, sillimanite, sodium salts (other than common salt), stone, strontium, sulfur (byproduct), tantalum, tellurium, thallium, topaz (industrial), tripoli) uranium, vermiculite, wollastonite, and zirconium. In addition, a few minor geographic areas for which no statistics are available, are also omitted from the tabulation; it is believed that no significant quantities of minerals are mined in any of these areas. The statistics in these tables were derived principally from questionnaires sent, in cooperation with the United States Department of State, to the governments of each country. Supplementary sources were United States consular reports, the Imperial Institute's Statistical Summary of the Mineral Industry of the British Commonwealth and Foreign Countries, other official publications of various countries, the United Nations Statistical Yearbook, the Year Book of the American Bureau of Metal Statistics, Minerais et Metaux, business magazines, and company reports. Where official data were not available, esti-

Jan 1, 1953

By E. R. Spencer, E. R. Bauer

Previous studies and research efforts have shown that noise-induced hearing loss (NIHL) is a problem in the U.S. mining industry. In response, researchers at the National Institute for Occupational Safety and Health (NIOSH) have been conducting a cross-sectional survey of equip­ment noise and worker noise exposures in the mining industry to estimate the potential for NIHL within the mining community. One commodity recently surveyed was the extraction of sand and gravel from surface pits and by dredging. To address the potential for NIHL in the sand and gravel industry, sound levels on and around the dredges and processing equipment were recorded to iden­tify areas of high noise levels. Full-shift worker dosimetry, in conjunction with task observations, was documented to determine the relationship between exposure and source. This paper presents research examining noise on dredges used in several surface mine sand and gravel operations and in the processing facilities. Results indicate that there are areas on the dredges (crane, suction pumps and diesel engines) where sound levels greater than 90 dB(A) are pres­ent. In addition, crushers and screens used in the processing of the sand and gravel also generate sound levels greater than 90 dB(A). Although no surveyed worker exceeded the Mine Safety and Health Administration’s (MSHA’s) permissible exposure level (PEL) of 90 dB(A) eight-hour time-weighted average (TWA8), laborers, mechanics, oilers, helpers, pickers and greasers are the workers most likely to be exposed to hazardous sound levels and to thus develop NIHL over time

By B. R. Klahold

Each year hundreds of mineral specimens and numerous inquiries regarding tests and analyses of minerals and related inorganic substances are received by the Bureau of Mines. In response to this demand, in years past Information Circulars were published containing a list of laboratories. This paper is a revised version of Information Circular 7523, The listing has been changed from a regional basis to one of States arranged alphabetically and grouped by cities, again alphabetically, with Alaska and Canada listed at the end. All the services given at these laboratories are listed on one page for convenience and brevity. This list is compiled as a public service, and none of the laboratories listed herein are recommended over any other nor can the Bureau of Mines vouch for their results.

Jan 1, 1954

"An active list of permissible explosives was published in July, 1930 as part of the United States Bureau of Mines Report of Investigations 3025, under the title of “Active List of Permissible Explosives and Blasting Devices Approved Proir to June 30, 1930”. Changes on that list were authorized in August, September, October and November, 1930, and January, March, April and June, 1931, as published in Reports of Investigations 3029, 3037, 3046, 3053, 3069, 3089, 3099, and 3123, respectively, By these changes the following explosives were added to the active permissible list:Big Red No. 9 Hercogel CBlack Diamond No. 5-A Liberty No 1Black Diamond No. 9 Liberty No. 2Burton 5, L. F. Liberty No. 3Burton 7, L. F. Liberty-Gel L.P.Duobel No. 4, L. F. Wesco Coal Powder No. 1Genigel No. 1and the permissible explosive EP-28 was transferred from the active to the in active list of permissible explosives.During June the following permissible explosives were added' to the active permissible list:Austin Red Diamond No. 9-B, L. F. BurtonAustin Red Diamond No. 9-C, L. F. Gelobel No. 4, L.F.Austin Red Diamond No. 10-A, L. F. Liberty No. 6Austin Red. Diamond No.12-A, L. F. Monobel 8 L.F.,- WR Austin Red-D-Gel"

Jul 1, 1931

By Dana Reinke, Launa Mallett

Interest in training evaluation in the mining industry was piqued with the promulgation of Title 30, Part 46, of the Code of Federal Regulations. Under Part 46.3, a training plan is considered to be approved if it contains certain information, including “The evaluation procedures used to determine the effectiveness of training.” The present paper is a broad overview of training evaluation and is intended to give trainers and decision-makers a framework for planning or assessing training evaluation strategies. It discusses questions to consider when starting an evaluation plan, Kirkpatrick’s model of evaluation categories, and various ways to collect data. It does not provide detailed instructions on how to develop evaluation methodologies, but reviews topics to consider when creating an evaluation plan. Training evaluation is a term that has many different meanings: assessing the quality of a course, effectiveness of materials used, teaching style of an instructor, or the comfort of a classroom. An evaluation can be done informally over lunch or with highly structured data-gathering tools. It can produce results that are useful to trainers, program administrators, corporate decision-makers, or no one. The key to a worthwhile evaluation is clearly defining why the evaluation is being conducted. Once the purpose is defined, planning the evaluation strategy can begin. For an evaluation to be effective, it should be incorporated into the development of the training activity itself. The training evaluation worksheet at the end of this paper can be used to guide evaluation planning.

Jan 1, 2002