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By R. L. Crosby

Microscopical and X-ray diffraction techniques were used to identify two intermediate phases in that part of the solid region of the magnesium-cerium system between and Mg3Ce. Previous literature had reported only one intermediate phase for this region, 1)12t chemical analysis determined the approximate composition of the two compounds to be Mg23Ce2 and Mg17Ce2. The range in composition of the two intermediate phases was found to be limited to less than 0.3 atomic percent cerium. The study did not determine the crystal structure of Mg17Ce2, but that of Mg23Ce2 is tetragonal with a = 10.33 A and c = 19.51 A.

Jan 1, 1966

By Fred Biggs, Walter Utt, Richard Miller

Powered haulage has been, and continues to be, a major source of severe accidents and fatalities at metal/nonmetal surface mines. Between 1986 and 1997, truck drivers accounted for63% of the lost-time injuries in surface haulage. This project was undertaken to reduce the number and severity of lost-time injuries among operators of these trucks. Work involved measuring shock acceleration at a western surface mine during representative work cycles on two types of trucks and collecting data from cab floors using a triaxial accelerometer and from operator seats using a seat pad accelerometer. NIOSH researchers also used the mine’s GPS systems to locate shock events on a mine map in real time. Shock tests were also run at Caterpillar, Inc.’s, proving grounds in Green Valley, AZ, to determine the magnitude of shocks resulting from controlled rock drops onto the bed of a haulage truck.

By Staff

The goal of the U.S. Bureau of Mines diesel engine research program is to reduce exhaust emissions from diesel-powered equipment used in underground mines. This research has led to significant advances in aerosol measurement and to the development of more effective emission controls. This Information Circular contains reports of some of the presentations made at the Bureau's Information and Technology Transfer Seminar on Diesels in Underground Mines given in Minneapolis, MN, on September 29-30, 1992. The seminar emphasized the measurement and control of diesel particulate matter emissions. Topics covered include a discussion of the health issues associated with the use of diesel equipment underground, an overview of regulations, measurement techniques for diesel exhaust aerosol, levels of diesel exhaust pollutants found in mines, and modern emission controls. An appendix is included that contains a report describing the capabilities of the Bureau's diesel emissions research laboratory, two papers describing the effects of engine maintenance or: emissions, a paper describing the monitoring of carbon dioxide in mine air as an indicator of air quality, a glossary, and a list of abbreviations and acronyms.

Jan 1, 1992

By H. H. Fields

The Bureau of Mines conducted research to determine the effectiveness of long holes drilled in solid virgin coal in degasifying an area of the Pittsburgh coalbed showing that horizontal holes drilled into a virgin coalbed from the bottom of any shaft will effectively remove methane gas in commercial quantities from the Pittsburgh coalbed. The in situ pressure at a depth of 214 feet into the coalbed and the average gas and water flows from the five degasification holes were 3 lb/in2 gage and 860,000 ft3/d and 1.7 gal/min, respectively. On June 19, 1975, after 593 days of degasification, a compressor was installed and pipeline quality gas was introduced into a commercial pipeline. As of June 1, 1976, after 1,022 days of degasification, over 753 million cubic feet of gas had been drained and 117 million cubic feet of gas had been purchased by the gas company for use in the local community of Wadestown, W. Va. The gas drained to date is six times the gas estimated to be in the area subtended by the holes. Methane emissions at the working face of 1 West mains, Federal No.2 mine has been reduced by 50 pct, proving the value of methane drainage by horizontal degasification holes drilled from shaft bottoms ahead of mining.

Jan 1, 1976

By A. J. Kauffman Jr.

The Petrographic Section of the Bureau of Mines, Northwest Electrodevelopment Laboratory, Albany, Oreg., annually examines thousands of minerals and rocks. Samples are received from mining, engineers, prospectors, and government agencies, both State and Federal. During the past 2 years certain uncommon minerals have been identified in the samples submitted. Eleven occurrences have been selected for reporting in detail. These selections were made because in most cases a new locality is involved. The data reported are the result of application of the latest techniques, and widely disseminated references concerning each mineral have been added for completeness. Several occurrences have been described by other investigators; in those cases new data have been supplied to supplement the already published information on these occurrences. No uranium-bearing minerals have been included; they will be treated in another paper. The Bureau of Mines does not make chemical analyses or assays for individuals or firms In direct competition with private laboratories. Mineral¬ogical examinations, however, are made for prospectors and the general public. Such examinations a call surface to determine whether the sample in question has possible commercial value. If it has apparent value, the sender is so informed, and suggestions as to its .Arc, development and marketing are offered. The latest scientific apparatus is available to aid in identification. The apparatus includes microscopes, both wide-field and polarizing, a Bunsen-type spectroscope for visual observation of the Zinc and band spectra of many elements, differential thermal apparatus for the examination of hydrous material, apparatus for cutting and mounting either thin sections for study in transmitted or polished surfaces for reflected-light studies, and a high-intensity magnetic separator for concentrating minerals according to their magnetic susceptibility. Also, available, but not an integral part of the Section, are several laboratory-type Geiger counters, a grating spectrograph, and X-ray diffraction apparatus. If need be, all of these tools may be employed to identify a mineral or rock.

Jan 1, 1950

By R. J. Hundhausen

"INTRODUCTION Preliminary examination of the Blue Ledge mine was made by O. H. Metzger, a Bureau of Mines engineer, in May 1943. A result of his recommendations; a Bureau of Mines sampling and exploration project was begun by J. R. Reynolds in October 1943 and continued to December when it was recessed for the winter. The project was resumed by the auther in May 1944 and was completed in November 1944. The Federal Geological Survey 3/ assisted by mapping the geology of the mine and logging the diamond-drill cores obtained from the Bureau's exploration Company maps, diamond-drill-hole records, several reports, and other data on the property were made available to the Bureau by D. C. Brown, of Towne Securities Corporation, owner of the Blue Ledge group of claims. E. A. White, general manager of the Tacoma Smelter of the American Smelting & Refining Co., supplied statistics for all ore that has been purchased from the Blue Ledge mine by his company."

Oct 1, 1947

By Chas. F. Jackson

This paper is published as a progress report for the first half of 1929 on the study of wining methods and costs in the Eastern and Central States. Data obtained from 25 mines using open-stope methods are correlated and summarized. Some of these mines have been described in considerable detail in reports already published as Information Circulars. In addition to the published reports on individual mines, considerable data have been obtained from other mines which were visited and studied during the course of the investigation. Many of these mines will later be described in detail in separate papers, and when the field has been covered in this manner it is planned to issue a bulletin on open-stops methods of mining which will amplify the subject matter of the present paper. Definition of ?Open-Stops?. - The term "open-stopes" as employed by the Bureau of Mines is applied to all naturally supported stopes; that is, stopes in which the excavated ore is not replaced by support of an artificial nature other than preps or stulls and in which the ore or (and) capping are not caved during the active life of the stopes.

Jan 1, 1931

By D. A. Stanley

The Bureau of Mines conducted laboratory-scale experiments to determine whether or not surface waters with a high organic content could be purified sufficiently to be used to replace the natural high-quality deep well water currently being used in the silica flotation step of phosphate rock beneficiation. Waters abundant in organic matter were collected from two central Florida streams, flocculated with a cationic polyethylenimine polymer, and processed in a sand filter. This treatment removed most of the organic materials from the water. Untreated surface water, treated surface water, and distilled water were used to compare the flotation response of the acid insolubles in an amine flotation circuit. Surface water treated with PEI-1000 was shown to be as effective as distilled water for the acid-insoluble-flotation step. Flocculation and filtration can therefore produce water suitable for amine flotation of quartz, which would permit substitution of surface water for deep well water.

Jan 1, 1981

By William R. Barton

Sampling to determine development potential of beryllium deposits was conducted at 31 New England localities. A total of 54 additional areas where the geochemical environment appeared favorable were sampled to determine if economically interesting percentages of beryllia (BeO) might occur. Newry Hill-Plumbago Mountain, Maine, Iron Mountain, N.H., and Long Island, Maine, were investigated in some detail to determine the size and grade of deposits. The mineralized pegmatites at Newry Hill-Phunbago Mountain are extensive but very low grade; at Iron Mountain the ore bodies are very rich but of small volume; at Long Island beryl occurs with molybdenite, wolframite, and scheelite, but the tonnage of ore was not determined.

Jan 1, 1968

Since its creation in 1910, the Department of the Interior's Bureau of Mines has pioneered in the development of mineral technology, through research. From the very beginning, research on mine health and safety has been a dominating concern, and a responsibility that expanded markedly as a result of the Coal Mine Health and Safety Act of 1969. Until the mid-1970's research on fuel technology and coal production also was an important part of the Bureau's work. But in the four years following the 1973 oil crisis, Congress established a reorganized Federal energy research apparatus in which all fossil fuel research-encompassing extraction, use, and conservation-was centralized. Today, the Department of Energy houses Federal research on coal mine production technology, while research on coal and noncoal mine health and safety and environmental technology, and on noncoal mine production technology, remains in the Interior Department as a continuing responsibility of the Bureau of Mines. In carrying out its authorized research programs, the Bureau conducts both short- and long-term re-

Jan 1, 2012

By J. L. Konchesky

In gasifying pulverized coal with steam and oxygen, the particle size of the coal fed to a gasifier should be as small as economically possible. A potential way to achieve this advantage is to reduce the particle size of the coal by passing the coal-steam mixture at high velocity through a heated tube coil before the mixture enters the gasifier. To evaluate this method the Federal Bureau of Mines flashed coal-water slurries in externally heated metallic tube coils to determine the extent of size reduction. The first of two different laboratory-scale apparatus reduced the average particle diameter of subbituminous C coal from 190 to 110 microns at an outlet velocity of 330 feet per second (f.p.s.). At the same outlet velocity, a second apparatus reduced the average particle diameter from 250 to 140 microns. An increase in velocity produced more finely divided coal, but variation in temperature and pressure had no effect except as they affected velocity. Virtually the same size reduction was noted for five ranks of coal at equal velocities. The rate of increase in particle-size reduction with increase in velocity decreased with a decrease in particle size. The pulverizing mechanism was concluded to be abrasion of the particles with each other and with the tube wall.

Jan 1, 1961

By W. H. Oppelt

The continuous gasification of lignite in an externally heated alloy-steel re-tort was investigated by the Bureau of Mines, Grand Forks, N. Dak., from 1945 to 1951. The main objective of the long-term experimental program was to obtain data on the mechanical performance of this type of gasification retort, particularly the alloy-steel heat-transfer surface of the retort, when operated on large pilot-plant scale. At the same time, extensive experimental data were obtained concerning the effect of process variables and the effect of a limited number of design modifications on gasifier performance. In the period covered by this progress report 4 pilot-plant runs totaling 2,879 hours of operation were completed with the rolled-plate, 310-alloy reaction tube. Over 30 million cubic feet of gas, having H2-CO ratios from 2.1 to 4.4, was made by the partial gasification of 636 tons of 1-1/2-by 3/8-inch natural lignite. Rates of gas generation were from 8,200 to 14,300 cubic feet per hour. Three of the four runs were carried out with the lowered gas offtake or continuous-annulus design modification of the gasification retort. In the final run of the series, gasification of lignite from seven different mines in North Dakota and Saskatchewan, Canada, was investigated at similar combustion-space temperatures and lignite and steam feed rates.

Jan 1, 1955

By Oliver C. Ralston

[This paper is an expmded revision of a report entitled "Froth Flota- tion and Agglomerate Tabling of Honmetdlic Idinerds, " published in Trans- actions of the Canadian Ir-stitute of Iriining and !,letdlurgy (vol. 40, November 1937, pp- 6? 1-726) and al'enared a year pr~viousl:~. Revisions en'oodied herein brinc the &ta I:T to Jn?uac"g 1, 193;. References have also been added to make the earlier paper more complete for the period it covered. This paper is an expmded revision of a report entitled "Froth Flota- tion and Agglomerate Tabling of Honmetdlic Idinerds, " published in Trans- actions of the Canadian Ir-stitute of Iriining and !,letdlurgy (vol. 40, November 1937, pp- 6? 1-726) and al'enared a year pr~viousl:~. Revisions en'oodied herein brinc the &ta I:T to Jn?uac"g 1, 193;. References have also been added to make the earlier paper more complete for the period it covered.]

Jan 1, 1938

By Warren M. Mahan

A rotary kiln process was developed by the Federal Bureau of Mines to produce consistently an iron product containing 3 to 7 percent nickel. Cuban laterite and serpentine ores were smelted in a gas-fired batch-rotary kiln) 5 feet in diameter and 9 feet long. The metal contained 2 to 4 percent carbon, with little or no silicon, and could be produced on a large scale with modest capital investment. A total of 121 tests was run using this procedure. The tests were conducted with a maximum temperature of 2,625° F., using linings of firebrick containing 40 to 70 percent alumina. Slags in the kiln were acid to neutral. The material in each batch passed through three stages: (1) Sponge metal, (2) carburization, and (3) balling and meltdown. Half the tests were made while firing the kiln with atmospheric-temperature air; the remainder were fired with preheated air. Tests showed that preheated air decreased fuel requirements, dust losses, and reducing agent, and increased the capacity of the kiln.

Jan 1, 1960

By R. H. Sprute

This report describes a feasibility study to consolidate coal waste sludge in a 100-acre pond by applying direct current between floating and buried electrodes. The study was conducted by the Bureau of Mines under a cooperative agreement with Washington Irrigation and Development Co., located near Centralia, Wash. Part 1 covers results of laboratory tests at the Bureau's Spokane Research Center and a small-scale field test at the cooperator's coal preparation plant in western Washington. The process is efficient and cost-effective when power is applied at low current density. A proposed system, fully described in part 2, has electrodes covering 21 acres of pond surface radially arranged around a central power platform. Densification of pond contents would require 2 to 3 years of treatment. Total cost of equipment, labor, and material is approximately $500,000.

Jan 1, 1982

[This is the sixth in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative Agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of tines of the Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935.-36.3/ The present report cover brands of gasoline represented by 1,490 samples plus thus: from the Pacific Coat, which ;sere averaged by the Pacific Coast Technical Group before being submitted and are published exactly as they were submitted. In some areas reports were received from 8 to 10 companies on the same brands of gasoline, Whereas in other areas only one Company reported on a brand. Thus, it can be seen that soma of the data are more representative than others. The inclusion of data from several cities within some of the districts has improved the report by reducing the number of brands reported by only one company. Severe changes have been made in the districts. A new district, Memphis, Tenn., has been formed to include Arkansas any western Tennessee. The Rocky Mountain area, have been divided into three sections. Salt Lake City and Denver form the Middle Rocky Mountain district; Laramie, Wyo., Idaho, Montana, and. Spokane, Wash., are included in the North Rocky Mountain district, and Arizona, New Mexico , and El Paso, Tex., have been combined to represent the South Rock Mountain district. The Cleveland district has been expanded to include Ohio ant. Indiana. Eastern Pennsylvania, Maryland, and northern Virginia are included in the Washington (D. C.) district. The Atlanta district includes Georgia, South Carolina; Mississippee, and northern Florida.]

Jan 1, 1938

By S. J. Hemberger, F. W. Lee

"This project constitutes the results of a geophysical field investigation undertaken in the mining areas in the vicinity of Marion, Crittenden County, Kentucky.Results were obtained at well-known mines being worked for fluorspar. Of special interest was the determination of mineral trends at such mines, particularly in relation to the fault patterns, because of ore in them.This work also constitutes a comparison between the field information that can be obtained by purely geological means and the additional information obtained by applying geophysical surveys to the same areas.As the mineralization in this area is controlled almost surely by the faults therein, the great importance of locating faults cannot be over emphasized. Accordingly, there has been incorporated herein the analyses as well as the application of electrical resistivity methods for fault determinations.In the western part of Kentucky, particularly in that area designated as the Cave-In-Rock quadrangle by the United States Geological Survey, is located the center of the fluorspar mining district of Kentucky. From the mining as well as commercial viewpoint, this area is of considerable interest and importance. It has been described by Currier4/ as a large structural dome that collapsed, through faulting, into a mosaic composed of a main fault pattern that has a strike to the northeast in sedimentary formations. Accompanying this main fault pattern are a large number of irregular faults. This fault complex is also traversed by a dike pattern that has a regional strike for this region focusing a northwesterly direction. The faulting occurred before the dike intrusions, the latter being composed largely of peridotite rocks. According to Reed,5/ most of the metallic mineralization, composed chiefly of galena and sphalerite, occurs at or near the Intersection of the dikes with the faults, indicating a possible igneous origin of the ore deposits. Reed adds that the fluorspar generally does not follow this rule but may also be found in other portions of the faulted zone not directly related to dike intrusions. The area may be considered of equal interest in the occurrence of lead and zinc and in the occurrence of fluorspar controlled by the faults. Hatmaker and Davis6/ give detailed information concerning the form of the ore bodies and economic factors that control ore production in this area; they also suggest the application of geophysical methods in this territory. Ulrich and Smith7/ also discuss geological details in this area. This area is therefore of interest, whether examined from a large structural point of view or from a very detailed angle. The former will assist in determining the origin of the mineralization and its economic possibilities, whereas the latter will give details concerning fault locations and their geologically and geophysically controlling features. This work was undertaken as a pilot investigation relating to the study of the location of fault occurrences, in which it was attempted to determine the location of faults as well as the fault patterns in certain isolated areas. No effort was made to identify the mineralization from the gouge material in the faulted zones; this problem was left for subsequent investigations."

Jun 1, 1946

This is the sixth in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935-36.3/ The present report covers 54 brands of gasoline represented by 1,480 samples plus those from the Pacific Coast, which were averaged by the Pacific Coast Technical Group before being submitted and are published exactly as they were submitted. In some areas reports were received from 8 to 10 companies on the same brands of gasoline, whereas in other areas only one company reported on a brand. Thus, it can be seen that some of the data are more representative than others. The inclusion of data from several cities within some of the districts has improved the report by reducing the number of brands reported by only one company. Several changes have been made in the districts. A new district, Memphis, Tenn., has been formed to include Arkansas and western Tennessee. The Rocky Mountain areas have been divided into three sections. Salt Lake City and Denver form the Middle Rocky Mountain district; Laramie, Wyo., Idaho, Montana, and Spokane, Wash., are included in the North Rocky Mountain district, and Arizona, New Mexico, and El Paso, Tex., have been combined to represent the South Rocky Mountain district. The Cleveland district has been expanded to include Ohio an,"- Indiana. Eastern Pennsylvania, Maryland, and northern Virginia are included in the Washington (D. C.) district. The Atlanta district includes Georgia, South Carolina; Mississippi, and northern Florida.

Jan 1, 1938

By Robert B. Hoekzema

The Bureau of Mines and U.S. Geological Survey completed a 4-yr (1979-82) mineral appraisal of the Chugach National Forest (CNF), AK. This report summarizes the Bureau's placer gold studies in the CNF. Placer mining from the mid-1890's through 1982 produced an estimated 133,800 oz of gold, of which two-thirds was produced prior to 1920. As much as 6,800 oz of placer gold was produced from 1979 to 1982. Most production came from Crow, Canyon, and Resurrection Creeks. Five types of placer gold deposits were identified in the CNF: (1) alluvial placers, (2) bench placers, (3) eluvial placers, (4) glacial placers, and (5) marine placers. Placer sampling indicated a potential for gold production from alluvial and bench placers associated with historically mined drainages such as Crow, Canyon, Resurrection, Sixmile, and Mills Creeks and from unmined drainages including the Avery, Kings, Snow, Copper, and Tasnuna Rivers and several smaller streams throughout the CNF. Results of fineness tests indicated that gold from the CNF ranges from 455 to over 950 fine. Subsequent investigations in drainages with anomalous placer sample values also identified previously unknown lode mineralization.

Jan 1, 1986

By J. H. East, D. Harrington

"INTRODUCTION The tremendous expansion of industry during the war and the unprecedented demands for metals and minerals are reflected in the production and use of explosives during that period. The increased use of explosives brought added safety problems to industry because of the necessity of using men as blasters who were not entirely familiar with and some who were totally unfamiliar with the characteristics of some or all of the various explosives. A discussion of the characteristics of the ordinary types of explosives used in: industry should assist in giving a better understanding of the hazards attending their use. Explosives are compounded so they may be used with reasonable safety provided the user understands and follows the procedure recognized as standard safety practice. Short cuts and the failure to understand and use recognized safe practices, as well as the selection of explosives unstited for the work at hand, are all part of the safety problem,The extent to which explosives are used in the United States is shown by a study of the statistics compiled by the Bureau of Mines 4/ regarding them. Some of these statistics are shown below and serve as an indicator of the tremendous number of men engaged in the transportation, storage, and use of explosives. Theme men are exposed to the inherent hazards attending this occupation and they should be familiar with the recognized safe practices relative to explosives."

Sep 1, 1946