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By William J. Campbell

Evaluation by the Bureau of Mines of published expansion values for magnesium oxide shows significant variation in values, which may be attributed to sample variables, experimental errors, or systematic differences between measuring techniques. To eliminate the sample variable in measuring expansion, thermal expansion characteristics of a high-purity polycrystalline magnesium oxide were determined by 21 cooperating laboratories using one or more of the following techniques; X-ray camera, X-ray diffractometer, dilatometer, interferometer, and telemicroscope. All expansion values were corrected by the author to a single reference temperature of 25° C. Linear expansion was expressed as a power series in the form of the following equation. Expansion (percent) = [[ A + B (?t) + C (?t)2] ?t 104] The constants, A, B, and C, were determined by least square techniques for X-ray camera, X-ray diffractometer, and dilatometer data separately, and for combined data of all five techniques. Expansion values are tabulated from 26° C. to 1,400° C. in 2° C. intervals using constants derived from X-ray camera data. Below approximately 500° C., expansion values obtained by dilatometric and interferometric methods are significantly lower than those by X-ray methods; above 500° C., this bias decreases rapidly. Comparison of results within methods showed the least variance for X-ray camera results; dilatometer and X-ray diffractometer results have about the same variance. The average deviations, in percent, between observed and calculated expansion values among methods were approximately 10 percent from 100°C. to 300°C., 5 percent from 300°C. to 500°C., and 2 percent from 500°C. to 1,400°C. Maximum deviations were approximately twice as large in most instances.

Jan 1, 1962

By David J. Kusler

A gravimetric method for the determination of carbon dioxide, carbon monoxide, hydrogen, methane, and oxygen in blast furnace top gas is described. Nitrogen may be determined directly by volume measurement or by difference. The method is direct, permits continuous as sampling, and provides an averaged analysis over a selected range of sampling intervals from 1/2 to 24 hr or more. Neither expensive equipment nor specialized personnel are required. The method is suitable for routine analysis, and the results compare favorably with those obtained by established methods.

Jan 1, 1963

By L. B. Pankratzt

The heat content above 298.15° K of ferroelectric lithium columbate (LiCbO3) was measured to 1,770° K. The Curie temperature was determined to be 1,450° K, the melting point 1,540° K, and the heat of fusion 16.94 kcal/mole. Heat content and entropy increments have been tabulated for the temperature range from i98.15° to 1,800° K. Heat contents are also given in equation form.

Jan 1, 1966

By Frank S. Wartman

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Jan 1, 1927

By F. F. Netzeband

This report relates to the sulfur industry of seven States--Arkansas, Kansas, Louisiana, Mississippi, Missouri, Oklahoma, and Texas--and is part of a national study of the sulfur industry by the Bureau of Mines. Markets as used in this report are divided into two components for individual analysis-- (1) supplier markets which include regional Frasch and byproduct sulfur producers and (2) consumer markets which include processors and manufacturers requiring sulfur in their operations The term sulfur as used in this report includes brimstone, native sulfur, elemental sulfur, or sulfur equivalents.

Jan 1, 1964

By S. H. Lorain

This paper is one of a series being published by the Bureau of Mines describing the mines and mills and subjects related to mining in western mineral areas. Although mining districts in the Tobacco Root Mountains are numerous there is a strong similarity in the character of the ore deposits and in the climatic and economic conditions affecting mining throughout the region. Individual mines are small, but the production of lode mines

Jan 1, 1937

By B. W. Gandrud

This is the first report published by the Bureau of Mines on washability characteristics of coal from beds in Tennessee. It is based principally upon screen-sizing and float-and-sink tests of raw coal from a bed on the Cumberland Plateau. Stripping operations were undertaken recently on this bed by the Cumberland Collieries, Inc., near Chalybeate,Van Buren County, Tenn. The bed has not been definitely correlated, but it may be an extension of the Sewanee bed, which has been mined extensively in the Tracy City district to the south-vest and at points near Dunlap and Pikeville to the southeast and east. It was spoken of by officials of the Cumberland Collieries as the Sewanee bed at the time of sampling for this study. In a letter dated October 16, 1948, W. D. Hardeman, geologist of the Department of Conservation, Nashville, Tenn., states: "The stripping operations of the Cumberland Collieries near the old postoffice at Chalybeate are, I am fairly certain, in the upper part of the Whitwell shale, which carries the Sewanee coal. This coal may be a stray seam, but it probably can be correlated with the Sewanee coal, which is mined farther east. "There are no detailed geologic maps or reports covering the area, and this opinion is based on what was observed in visiting the strip mines in that general vicinity." The laboratory work upon which this report is based was done at the Southern Experiment Station of the Bureau of Mines, United States Department of the Interior, in cooperation with the University of Alabama and the Cumberland Collieries, Inc.

Jan 1, 1949

By F. F. Netzeband

This report relates to the sulfur industry of seven States--Arkansas, Kansas, Louisiana, Mississippi, Missouri, Oklahoma, and Texas--and is part of a national study of the sulfur industry by the Bureau of Mines. Markets as used 1n this report are divided into two components for individual analysis--(1) supplier markets which include regional Frasch and byproduct sulfur producers and (2) consumer markets which include processors and manufacturers requiring sulfur in their operations. The term sulfur as used in this report includes brimstone, native sulfur, elemental sulfur, or sulfur equivalents.

Jan 1, 1964

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 R. G. Travis

1. Reserve estimates have been made for eight coal beds in Monongalia County, W. Va., but only the Pittsburgh, Sewickley, and Upper Freeport beds are important at this time. The Pittsburgh, Sewickley, Waynesburg, and Upper Freeport beds contain the largest recoverable reserves. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 short tons per acre-foot of coal in place, are estimated at 3,526 million tons as of January 1, 1954. Of this total, 3,294 mil-lion tons is in beds 28 inches and more thick. Areas in each bed except the Pittsburgh were omitted from the estimate because available data relative to the bed characteristics are too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1956

By W. A. Stickney, J. W. Town

Studies on continuous - circuit leach - aluminum precipitation and leachelectrodeposition of mercury were made by the Bureau of Mines to determine optimum conditions and cost estimates for recovering mercury from mercury sulfide flotation concentrates . With 150 grams of sodium sulfide and 50 grams of sodium hydroxide per liter , from 98 to 99.8 percent of the mercury was extracted from flotation concentrates , with about 0.5 pound of sodium hydroxide used per pound of mercury produced . Precipitation of mercury from the caustic - sulfide solution with minus 8 - mesh aluminum shot required about 0.2 pound of aluminum per pound of mercury produced at a cost of $ 0.05 per pound of mercury . Electrodeposition cost with 7 mill power , based on 50 percent current efficiency , was below 2 mills per pound of metal deposited . Feed solutions ranged from 10 to 130 grams of mercury per liter , and current densities , from 2 to 70 amperes per square foot . The cost of open- pit mining 250 tons per day was estimated at $ 1.75 per ton , and flotation - leachingelectrodeposition of the ore , at $ 3.54 , resulting in a cutoff grade of about 0.1 percent mercury . The cost of underground mining 50 tons per day was estimated at $ 20.00 per ton , and the cost of milling the ore was estimated at $ 13.33 , which resulted in a cutoff grade of 0.6 percent mercury .

Jan 1, 1964

By J. H. Jacobs

In late 1946, research was begun at the Bureau of Mines Electrometallurgical Laboratory at Boulder City, Nev., to determine the possibility of electrowinning manganese from chloride electrolytes on a continuous basis. All phases of electrodeposition were investigated on a small scale it the laboratory, and the results were reported by Jacobs and Churchward. These results indicated that a chloride process had certain possible advantages over the sulfate process that made it worthwhile to continue the investigation on a semi-pilot-plant basis, and this paper reports the results of this work. Research and development work on a process for electrowinning manganese from low-grade ores has been carried on intermittently by the Bureau of Mines since 1936. A process was developed, using sulfate electrolyte, that has been extensively described in the literature.

Jan 1, 1951

By Robert L. Rough

The 1954 field tests consisted of six experimental shots in relatively deep holes in a sandstone similar to many oil-bearing sandstones. Water-injection measurements were made before and after each shot to establish the change in conductivity of the fluid caused by the shot. The pressure pulse produced by the shot was recorded in nearby holes to monitor the shot and to determine if any relation existed between the change in conductivity and the nature of the pressure pulse. The results of water-injection tests showed the range of conductivity of fluid before and after shooting with two different types of explosives. Because of the large spread in data for similar shots, not enough information was available to evaluate the differences in increased conductivity produced by the two explosives or any relation between the increased conductivity and the nature of the pressure pulse. However, these results, with the results of other tests involving explosive shots in rock, provide guidance for future research on the oil-well-shooting problem.

Jan 1, 1957

By W. P. Yant

[At the majority of mines where flame safety lamps are used either as working lights or as a means of detecting gas, no check it made on this condition of the various parts of the lamp and their assembly other than a visual ink inspection. Although this inspection should be made carefully in view of tae serious consequence that may follow Vie use of a faulty lama, In many instances the inspection is of a perfunctory nature. The Bureau of Mines has therefore designed a small box or gallery for testing lamps for defects and improper assembly before they are taken into the mine. The test simulates the condition when a lamp is extinguished by its introduction into an explosive mixture and the operator attempts to relight the wick while the lamp contains the explosive mixture. This test is more rigorous than merely subjecting a lighted lamp to an explosive methane-air mixture. In the latter test the products of combustion tend to blanket the propagation of flame from within the lamp to the exterior, especially if there are defects at the top of the gauzes. Moreover, when the lighted lamp is subjected to an explosive methane-air mixture the methane builds up slowly within the lamp until the lower inflammable limit is attained, whereupon a feeble explosion occurs within. If the nonlighted lamps is first filled with the methane-air mixture that gives the maximum violence and is than ignited, the dampening effect of products of combustion is obviated and the strain on defects is]

Jan 1, 1930

By R. H. Bedford, F. T. Johnson

"In California the history of tin mining began in Riverside County in 1853, with the discovery of the Temescal deposit. This deposit remained the only one with a production record until recent small shipments were made from Kern and San Bernardino Counties.According to the California State Division of Mines, Temescal's total output has been about 125 tons of tin, all of which was produced in 1891 and 1892. It was idle from 1892 to 1928.An extensive but unsuccessful development campaign carried on in 1928 and 1929 by the American Tin Corp. produced only half a ton of the metal, and the property again was idle until 1943, when an attempt to resume operations proved unsuccessful. After 1929 no production is recorded from California until 1944 end 1945, when small shipments of sorted ore from Kern County returned about 2 tons of tin and 1-1/3 tons was recovered from sorted ore and concentrates from San Bernardino County. The total output of tin from California has been less than 150 tons, and less than 4 percent of this was produced in the last 50 years, in spite of numerous attempts during that period to promote tin mines,So marked a scarcity of a metal essential in war makes any occurrence interesting. When some prospects were reported to the Bureau of Mines in July 1942, in a new field 10 miles east of Gorman, they were at once examined and the preliminary exploration by the owners closely followed. Eventually one was explored by bulldozing end diamond drilling as a joint project by the Bureau of Mines and the Geological Survey.To supplement this joint project, the authors undertook independently a general survey of tin in California - a survey designed to check reported occurrences and to bring their status up to date. In this work, the 37 places described in the text and spotted on the accompanying map, (fig. 1) were visited end sampled. Although traces of tin were found in many pieces, nothing that suggested a tin mine was found anywhere, and it is difficult to base much hope for appreciable future tin production upon anything found thus far in California."

Apr 1, 1946

By T. H. Dubaniewicz, J. E. Chilton

Fiber-optic technology is progressing rapidly, including the development of fiber-optic sensors for many applications. These sensors have the advantages of high sensitivity, light weight, small size, high bandwidth, and freedom from electromagnetic influences. The U.S. Bureau of Mines is investigating the use of fiber-optic technology to monitor mine atmospheres. This report describes a methane monitor based on differential absorption of infrared light. The monitor can detect methane concentrations as low as 0.2 vol pct as far away as 2 km via fiber-optic cable. The upper range is 100 vol pct methane. Since the system requires no electrical power within the mine, it is intrinsically safe.

Jan 1, 1992

By Scott W. Hazen

COMPREHENSIVE summary is presented of results of several years of research at the Bureau of Mines Mining Research Center at Denver on adapting and applying techniques of statistical analysis in mine and mineral-deposit sampling and in computing grade and tonnage of ore for a mineral deposit. In addition to elementary statistical theory the material presented in the bulletin includes: (1) Certain special statistical techniques that have been found useful in mining applications; (2) problems, implications, and limitations that may be encountered in applying these techniques in mine sampling and evaluation; and (3) numerous examples to demonstrate application of the theory and techniques.

Jan 1, 1967

By A. J. Kraemer

This report on the physical and chemical properties of crude oils of California is one of a series on the producing districts of the United States. It includes a short discussion of results, tabulated data, and individual analyses of California crudes. Analyses of crude oils from the fields of Fresno, Kern, Los Angeles, Orange, and Ventura Counties have been published in Serials 25952 and 26083. The analyses reported in this paper corer samples that were obtained subsequent to the publication of Serials 2535 and 2608. The samples were obtained by members of the San Francisco office of the Bureau of Mines. The collecting of samples was facilitated by the courtesy of representatives of oil companies in California.

Jan 1, 1927

By Rogers F. Davis

This publication has been prepared to supply manufacturers and industrial users a listing of mobile diesel-powered equipment and subassemblies approved and certified by the Bureau of Mines for use in nongassy noncoal mines and tunnels. This revised and supplemented listing supersedes an earlier publication2 released in 1963. Testing of diesel-powered equipment is one phase of the Bureau's program of health and safety that concerns approval of electrical and diesel equipment designed to prevent explosions, fires, shocks, or toxic hazards in underground mines, when such equipment is used and maintained properly. Manufacturers submit machinery and component parts to the Bureau for study of their design, safety features, and use. Equipment must pass exacting tests and must meet strict requirements established through research and experience and outlined in the Bureau's permissible schedules before the Bureau approves it for safe use in mines.

Jan 1, 1968

During the interval 1929-41, geophysical exploration in Russia made considerable progress, as reflected in publications. The greater part of these publications was available during the preparation of Geophysical Abstracts and Ms been abstracted in them. The rest was not received and remained unaccounted for. A considerable portion of these lading publications are now listed in bibliographic form, in view of their interest to geophysicists. All publications entered in the bibliography are in Russian. 1. GRAVITATIONAL METHODS 1. Abakelia, M. S. The Organization of Gravitational Observatories in Transcaucasia. Problemy Sovetskoi Geologi, Moscow, vol. 6, No. 5, 1936, pp. 452-454.

Jan 1, 1945