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By T. A. Klinefelter

ONE OF THE many services rendered by the Federal Bureau of Mines is the identification and general examination of ore and mineral samples. Many of these, coming from almost every State in the Union, are clay and shale samples. Other Government agencies, State geologists, universities, and other laboratories are often requested to make similar examinations. This publication describes methods of testing these samples. An earlier paper, published in 1943, described Bureau of Mines methods of testing such clays.3 This paper was to be followed later with another (part II) that would describe much more thorough testing than did the rather general outline of part I. Part I has been out of print for some time and needs revision, and part II was never written; hence, the present publication is designed to include part I and also those additions intended as part II. The tests presented in part I were simple, requiring only the ordinary equipment to be found in any good chemical laboratory. The second publication was to include a greater number of test procedures and information on increasing the accuracy and precision of those previously given.

Jan 1, 1957

By S. M. Shelton, A. L. Engel

"This report presents the results of investigations of ore-testing projects assigned to the Ore-Dressing Section, Metallurgical Division, Bureau of Mines, at the Mississippi Valley Experiment Station, Rolla Mo. During the fiscal year ended June 30, 1941.The manner of approving ore-testing projects has been explained in a previous reports. 4/ The testing procedures likewise have been described. 5/The treatment methods described are based upon laboratory experiments with small amounts of sample and naturally are subject to the inherent, normal, limiting conditions of such procedure. It is not intended to describe treatments in detail, but rather to indicate applicable methods. Local operating conditions, when the laboratory results are applied to plant operations, may require further study. Large-scale pilot-plant tests should be made before commercial operations are begun, so that translation from the experimental stage will yield satisfactory results."

Mar 1, 1942

By Sean Gallagher, William S. Marras, Alan S. Litsky, Deborah Burr

This paper describes a comparison of the fatigue failure responses of older versus younger lumbar spine cadaver motion segment specimens. These specimens were repeatedly subjected to loads simulating those experienced by the spine in lifting a 9 kg load in different torso flexion postures (0, 22.5, and 45 degrees of flexion). An older sample of 36 motion segments (average age 81 years + 8 SD) is compared with a younger sample of 18 motion segments (average age: 47 years + 9 SD) with respect to the number of cycles to failure and results of survival analyses evaluating the effects of flexion and bone mineral content with and without the younger data set. Compared to the older sample of spines, the younger sample exhibited many more cycles to fatigue failure in all the torso flexion conditions (10020 versus 8267 average cycles to failure in 0 degrees flexion, 7124 versus 3262 in 22.5 degrees flexion, and 3229 versus 263 cycles to failure in 45 degrees flexion). The increased cycles to failure in young specimens is likely due to the increased bone mineral content (BMC) in younger motion segments (30.7 g + 11.1 g per motion segment versus 27.8 + 9.4 g). Cox regression analyses modeling both flexion effects and BMC indicate that betas are similar when just older spines are modeled and when younger specimens are included in the analysis. Betas for survival analysis models with and without younger specimens generally show little change for flexion (2.716 versus 2.756 for 22.5 degrees [0 degrees referent], 3.926 versus 3.380 for 45 degrees [0 degrees referent]). Bone mineral content shows a similar protective effect in both models (Betas: -0.127 versus -0.087). Overall, comparison of the models indicate that risk ratios are similar for 22.5 degrees flexion, slightly increased for 45 degrees flexion and slightly more protective influence predicted for BMC in the combined sample versus the older sample alone.

By G. Schuman

Variations in pyrite reactivity are known to exist within samples collected from different areas. Using samples collected from acid and non-acid sites, the relationship between the factors affecting pyrite oxidation and observed variations in pyrite reactivity was studied. Heavy liquid separations were used to extract the pyrite from nine pulverized rock, coal, and coal refuse samples. Simulated weathering tests were used to determine the degree of reactivity of the extracted pyritic material. Representative portions of each pyritic sample were analyzed for whole rock composition (including pyritic sulfur and neutralization potential), for elemental composition, and by x-ray diffractometry. The samples were also examined with reflected light microscopy to ascertain pyrite morphology distributions. Tests for the presence of iron-oxidizing bacteria were all negative indicating the leaching tests were conducted under abiotic conditions. The results of the simulated weathering tests permitted the partitioning of the samples into two groups based on positive or negative neutralization potential (NP) values. Determinations were then made to evaluate the degree to which a variety of factors, including temperature, partial pressure of oxygen and water, and crystallography affected pyrite reactivity. Multiple regression analyses showed no statistically significant relationship between degree of reactivity and elemental composition. However, for samples with negative NPs, a simple regression analysis showed a strong linear relationship to exist between the reactivity of the pyrite and the proportion of "unstable" pyrite (framboidal + mossy pitted) found in each extracted pyrite sample. Samples of pyrite with positive NPs, although producing acidity, did so in at least one order of magnitude less than the NP deficient samples, indicating the important role that NP plays in controlling pyrite reactivity. A simple linear regression between cumulative sulfate production and NP for the three samples with positive NPs had a correlation coefficient of 0.99. For the nine samples grouped together, a linear regression model between cumulative sulfate production and NP (both negative and positive) was established between log of sulfate and NP.

Jan 1, 1991

By R. S. Fowkes

Jetstream pressure distributions and coal cutting rates were determined for a number of nozzles and under different operating conditions. The jetstrearn pressure distribution data were fitted to an assumed curvilinear equation by the utilization of a numerical least-squares technique with the aid of a digital computer. Subsequent manipulation of the approximation equation showed that the total force of the jetstream, rather than its maximum pressure or total kinetic energy per unit Lime, was the most significant quantity affecting the coal cutting rate. A shorter method for assessing the ability of a nozzle to cut coal was found.

Jan 1, 1968

By David B. Doan

This regional report covers 1993 mining and related activity in approximately 40 countries and territories of Canada, Latin America, and the Caribbean Basin. These countries of the Western Hemisphere, as with the United States, are endowed with a great variety of minerals, including metals, industrial minerals, and energy minerals. For most of these countries, such mineral production helps form foundations for their economies and earns export credits including hard currencies. Table 1 depicts an overall view of Latin America and Canada's production of its major mineral commodities in 1993; subsequent tables show the role of Latin America and Canada in world mineral production, trade, and import dependency on minerals from Latin America and Canada by the United States. Overall, the picture emerges of a rich mineral diversity throughout the hemisphere, attracting increasing interest and investment, and complementing the mineral resources of the United States.

Jan 1, 1995

This publication summarizes, for all interested parties, the research, development, and demonstration in-house projets programed by the Bureau of Mines for fiscal year 1980 (October 1, 1979 - September 30, 1980) under its Minerals Health and Safety Research program. The objective of these projects is to provide an ordered and sequenced series of advances toward the Bureau's overall goal of providing the system technology required to create a healthier and safer working environment for the Nation's mining and minerals processing workers.

Jan 1, 1980

By G. H. Damon

Since 1963, Bureau of Mines Information Circular 8179 has served the mining industry as a fundamental safety guide in the field of blasting agents. In the intervening 14 years, many changes have occurred, and this report presents revised and new recommendations which recognize these changes. For example, AN-FO is now supplied mostly premixed, whereas in 1963 much of it was mixed by the blaster; aluminum metal (A1) and other fuels are now often added to AN-FO to increase strength, and flake aluminum powder is used as a sensitizer in water gels; and water gels or slurries that are now extensively used were just coming into practical use in 1963. To provide the widest possible margin of safety, some of the Bureau's recommendations are more stringent than existing regulations,

Jan 1, 1977

By W. F. Watts

This report describes a statistical analysis of 41,502 respirable quartz dust samples collected from 1974 through 1981 in metal and nonmetal mines and mills. The goal of this Bureau of Mines study was to identify commodities and occupations associated with high quartz dust exposure so that future enforcement and research activity can be focused on the high-exposure areas. For this analysis, the Bureau used its computerized Mine Inspection Data Analysis System (MIDAS), which contains data on nearly 350,000 air samples, including data for 61 contaminants in 45 commodities. The samples analyzed were collected by inspectors of the Mine Safety and Health Administration (MS HA). The data were entered into the MIDAS computer and coded according to commodity, occupation, location, and other categorical information. Occupations an. commodities with high quartz dust exposure were identified by grouping the data by code categories. Workers at sandstone, clay and shale, and miscellaneous nonmetallic mineral mills had the highest quartz dust exposures. Within these mills, occupations with high exposures were baggers, general laborers, and persons involved in crushing, grinding, and sizing operations. Dust concentrations in these mills were not necessarily the highest, but because the dust contained a high percentage of quartz, the health risk from dust exposure was the greatest.

Jan 1, 1984

By John W. Frey

Although there are certain general uniform provisions in the laws ... of the several Provinces of Canada the differences are so great that it is considered advisable to present digests of separate mining laws rather than a digest of Canadian mining law as an entity . This analysis , accordingly , has been divided as follows : Nova Scotia , New Brunswick , Quebec , Ontario , British Columbia , and a group of Provinces under Dominion Law .

Sep 1, 1930

By Frank J. Wiebelt

Under a general program to extend the resources of mineral deposits, the Bureau of Mines examined the Quien Sabe antimony mine in October 1948. The preliminary evaluation demonstrated that a diamond-drill program was warranted co establish the tenor and persistence of the veins and permit an estimation of antimony reserves. The Bureau of Mines conducted a diamond-drilling program on the property from December 1949 to May 1950. Ten holes aggregating 2,483 feet were drilled. Nine of the holes encountered antimony-bearing vein material.

Jan 1, 1956

By V. L. SKITSKY

Geophysical Abstracts are published by the Division of Geophysical Explo- ration of the U. S. Bureau of Mines as an aid to those engaged in geophysical research and exploration. Inasmuch as geophysicists in the field may have little opportunity to consult libraries, the policy of the Division is to provide abstracts suffi- ciently informative in themselves to keep readers abreast of literature and patents published in the United States and abroad. - DISTRIBUTION. Abstracts 1-86 were issued as Information Circulars by the Burca of Mines; Abstracts 87-111 appeared as Bulletins of the Geological Survey; Abstracts 112-127 have been published as Information Circulars by the Bureau of Mines; succeeding issues will be resumed by the Geological Survey.

Jun 1, 1947

By E. L. Garton

[Analyses of may crude oils produced in Louisiana are included in reports that t have boon published by the Bureau of Mines. The first report, giving, analyse of 6 Louisiana crude oils, was 3 published in 1921 and this was followed a year later by Report of Investigations 2416,4/ giving 7 additional analyses. The eleven most important of these analyses were incorporated in Bulletin 291.5/ issued in 1928 In 1934 analyses of 26 crude oils produced in southern Louisiana were published.6/ The percent report presents analyses of 72 additional samples of crude oil from 45 fields in 23 parishes In Louisiana.]

Jan 1, 1939

The coal-bearing strata of Oklahoma occur in the eastern part of the state over an area of 14,500 square miles, 20.7 percent of the state's total area. Commercially valuable deposits of bituminous coal cover about 8,000 square miles in seams ranging from ten inches to five feet thick. Estimated reserves in Oklahoma are 1.6 billion tons, representing 0.3 percent of U.S. coal reserves. The vast majority of coal mined in Oklahoma used in a single power plant within the state. Oklahoma gained primacy when its regulatory program was conditionally approved January 19, 1981. Authority for the state to administer the Abandoned Mine Land program was granted January21,1982. On April 30,1984, the Office of Surface Mining substituted direct federal enforcement of the inspection and enforcement portions of the Oklahoma program. This substituted enforcement was based upon a finding by OSM that Oklahoma had not operated the inspection and enforcement portions of its program effectively. As of January 1, 1986, Oklahoma inspection and enforcement authority was reinstated. Full program authority was granted to Oklahoma on January 14, 1986.

Jan 1, 1992

By James E. Norman

[The flotation of mica is mentioned frequently in the literature, but must of the references have dealt with the recovery of mica by the old anionic collectors. The first use of the new cationic reagents indicated their superiority- as collectors in the flotation and a. agglomerate tabling of micas, feldspars, quartz, clay, and other acidic mineral, but the separation n of these minerals from each other necessitated study of the flotation of each mineral.]

Jan 1, 1941

By James E. Norman

[The flotation of mica is mentioned frequently in the literature, but most of the references have dealt with the recovery of mica by the old anionic collectors. The first use of the new cationic reagents indicated their superiority as collectors in the flotation and agglomerate tabling of micas, feldspars, guartz, clay, and other acidic minerals, but the separation of these minerals from each other necessitated of the study of the flotation of each mineral.]

Jan 1, 1941

By C. F. Ellis

Interest in the composition of automobile exhaust gases has been greatly accelerated by recent studies that have indicated that these gases contribute to smog formation in urban areas. Several analytical methods have been published for the analysis of the hydrocarbons in the exhaust gases, but similar information has not been published on the analysis of the oxygenated compounds. This report presents procedures for chemical analyses of certain oxygenated compounds, procedures for sampling the exhaust gases for these analyses, and the analytical results of some experimental work in which these procedures were used. A stationary 1956 model, 170 horsepower, V-8, dynamometer-mounted engine, operated to simulate vehicular cruise conditions, was used for the study. Exhaust gases produced from a regular-grade Midcontinent gasoline during 15-40- , and 60-mile-per-hour cruise operations were analyzed by chemical methods for formaldehyde, total aldehydes, total carbonyls, total alcohols, carbon associated with the oxygenated compounds, and the oxides of nitrogen. Experimental results indicate: 1. The range of concentrations of the total of the functional groups of oxygenated compounds, expressed as moles per million moles of water-free exhaust gases, is about 90-100; the concentrations increase with engine speed. 2. Aldehydes comprise about 80-90 mole- percent of the total of the oxygenated groups, and formaldehyde accounts for about 50 mole-percent of the total aldehydes. 3. The order of magnitude of the concentration of the carbonyls is the same as that for the aldehydes, indicating that ketones are not a major group. A colorimetric test indicates that methyl ketones Constitute about 2 mole-percent of the oxygenated compounds.

Jan 1, 1961

Senior staff representatives of the Bureau of Mines and the National Institute for Occupational Safety and Health (NIOSH) met in Washington on September 6, 1972, to review and evaluate their cooperative accomplishments to date and to consider the planning and conduct of future coordinated activities. The six presentations given at this joint staff seminar are published here for the benefit of those concerned with the problems of coal mine health, and especially those with responsibilities in administering the Coal Mine Health and Safety Act of 1969.

Jan 1, 1972

The original manuscript of section 2 of this series of miners' circulars devoted to accident prevention in bituminous-coal mines was completed in September 1944. At that time roof bolting had been tried with some success in the lead-mining district of south-eastern Missouri, but information on the subject was so fragmentary that it was not included as a method of roof support. References to roof support in bituminous-coal mines, therefore, were confined almost entirely to conventional timbering methods. In 1947 the Bureau instituted a research program and intensive study of the general problem of roof control, which emphasized roof-bolt application. The rapid increase in mechanized mining following the close of World War II provided the impetus for the Bureau's roof-control investigations, because the vertical supports used with conventional timber restricted the maneuverability of mechanical face equipment, and the industry wanted to explore every possible method of eliminating interference with the production cycle to gain full advantage of mechanized mining. Moreover, the accidental dislodgment of vertical supports greatly increased the roof-fall hazard. As roof falls have killed and seriously injured more mine workmen every year than any other cause or classification of injury since records have been kept, the Bureau assumed this investigative leadership with the prime objective of substantially reducing the annual toll from falls of roof, including falls of rib and face.

Jan 1, 1958

The coal-bearing areas of Kansas cover approximately 18,800 square miles (23 percent of the state's total area). Coal in Kansas ranges from lignite to high volatile bituminous, located principally in the south-eastern part of the state. Kansas reserves are estimated to be 987,500,000 tons, approximately 0.2 percent of U.S. reserves. Coal beds generally occur in thin seams up to five feet thick. The overburden-to-coal stripping ratios in Kansas are among the highest in the nation, typically 20 to 1, with some ratios up to 35 to 1. The first commercial coal mining operation in Kansas opened in 1865 at Fort Scott in Bourbon County. As in other states, coal production in Kansas increased during the industrial revolution, and then fell as industry converted to alternative fuels. Production peaked in 1916 and 1917, with annual production of 7,250,000 tons. Coal production today is by surface mining methods. The Kansas regulatory program was approved April 14, 1982; the Abandoned Mine Land Program was approved February 1, 1982; and the emergency program authority was approved January 10,1989.

Jan 1, 1992