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By Phillip R. Moyle

In 1985 the U.S. Bureau of Mines evaluated the mineral resources of the Sheep Creek West Wilderness Study Area (ID-111-36A), Owyhee County, ID, for the U.S. Bureau of Land Management. The Wilderness Study Area consists of 11,680 acres centered approximately 20 miles south of Grasmere, 10. It contains no mines, claims, or prospects. No mineral resources were identified; however, a geode occurrence within and adjacent to the Wilderness Study Area, and minor amounts of placer gold along Sheep Creek, may be of interest to rorkhounds and recreational gold panners.

Jan 1, 1986

By W. R. Hardwick

Nuclear explosive fracturing has been suggested as a method to make hard rock amenable to extraction by a modified block-caving method. To evaluate this possibility, conventional and nuclear blasting practices are discussed, underground mining methods for large deposits and their costs are described, and the cost of fracturing ore with a nuclear explosive and subsequent mining by a modified caving system is estimated and compared with both open-stope and block-caving mining costs. While the direct cost of fracturing the ore in hard rock with a nuclear explosive is less than with conventional explosives, additional costs imposed by the use of nuclear explosives may make their use unattractive for deep mining.

Jan 1, 1970

By d&apos, Kathleen J. Amico

THIS summary appears in Minerals Yearbook volumes I and III, which cover mineral production in the United States, its island possessions, the Canal Zone, and the Commonwealth of Puerto Rico, as well as the principal minerals imported into and exported from the United States. The several commodity and area chapters contain further details on production. A summary table comparing world and U.S mineral production also is included.

Jan 1, 1964

By M. R. Geer

Three coals from the Wilkes on - Carbonado district of Pierce County , Washington , were subjected to washability analyses to estimate the amount and quality of washed coal obtainable . Because the coals were unusually difficult to clean , the washability examinations were supplemented by table tests , tests in dense - medium cleaning units , and flotation tests . None of the coals could be reduced to the desired 10 percent ash by tabling and the response to flotation by two of them was poor . Dense -medium treatment provided coal of the desired quality , but with the most difficult coal the recovery efficiency was lower than usual .

Jan 1, 1964

By H. Kenworthy

A zinc-pyrite ore from the Gray deposit in Jo Daviess County, Ill., was successfully concentrated on a laboratory scale. Initially, drill cuttings were submitted for separation of zinc and iron concentrates. Subsequent to mine development, a large sample of coarse ore was submitted to ascertain its amenability to sink-float treatment to produce a low-grade zinc-iron concentrate and discard a clean tailing. The samples of ore were submitted to the Rolla Metallurgical Branch by the Mining Division of the Federal-Bureau-of Mines. They were obtained during the recent war as a part of the extensive government program to increase metal production through exploration for new mineral deposits and investigation of old mineralized areas. The first sample consisted of about 3,000 pounds of drill cuttings collected, during the Bureau?s churn and diamond- drilling program. The second sample was taken at a later date, after Tri-State Zinc, Inc., had opened the deposit and commenced milling the ore. This sample consisted of a ?ton-of mill feed crushed through 2 inches and collected over a period of 3 days.

Jan 1, 1949

By C. A. Herbert

In summer, when hot, moisture-laden air enters a coal mine in the region east of the Mississippi River, the moisture is likely to condense on the roof and ribs because the incoming air is cooled below its dew point upon contact with the roof, ribs, and floor of the mine passageways. When the roof and ribs become wet owing to this condensation they are said to "sweat." In many mines, as soon as this sweating begins, shale or slate roof that appears solid and strong in winter begins to cut and fall. For a long time most mining men believed (many still believe) that the roof trouble was due to this sweating. However, from observation of conditions in one mine the operators concluded that the trouble was caused by expansion and contraction of the roof due to changes of temperature. This opinion was confirmed by experiments at several mines in cooling the air as it entered the mines. Methods used in these mines for cooling the air are described in this circular. MINE A At mine A the roof gave considerable trouble in the summer, and it was observed that where a spray of water from a leaking dam kept the roof wet and at a uniform temperature no difficulty was experienced with the roof, although it had cut and fallen on either side of that point. From this fact the company officials concluded that changes of temperature in the air rather than moisture caused the trouble and that if the incoming air were cooled to approximately normal strata temperature much of the additional roof trouble experienced during the summer would be overcome.

Jan 1, 1940

By E. G. King

Sodium-aluminum and calcium-aluminum silicates are important rock-forming minerals. While many of them are of only theoretical interest, several are of practical importance--as ceramic raw materials and as potential future sources of aluminum. Heretofore, thermodynamic data for these minerals were incomplete; and in many instances missing data were difficult to estimate reliably. This has seriously hampered thermodynamic calculations pertaining both to the natural formations of these minerals and to their decomposition in sintering and fluxing reactions. This paper reports the results of the Federal Bureau of Mines measurements of low-temperature heat capacities of four crystalline silicate minerals--dehydrated analcite (NaAlSi2O6), hexagonal anorthite (CaA12 Si208), lawsonite (Ca2Al2Si2080?2H20), and leonhardite (Ca2Al4Si8C24?7H2O). It augments previous similar measurements of related minerals, which were summarized recently.4 The measured heat-capacity data were used to derive entropy values for the four minerals at 298.15° K. Some relations between these entropy values and those of other similar minerals were discussed. These relations illustrate the difficulty of estimating entropy values of tertiary (or higher) silicates.

Jan 1, 1961

By J. R. White, S. W. Lambert, C. M. McCulloch

Examination of several coalbeds in Walker County, Ala., Cambria, Greene, and Fayette Counties, Pa., and Raleigh and Wyoming Counties, W. Va., indicates that cleat orientations are similar throughout a vertical sequence of strata. Studies of cleat orientation were carried out in underground mines that are operating in separate coalbeds vertically above one another. The data show that over a vertical separation of 100 to 400 feet, the average difference in coal cleat orientation between mines is 04° for the face and 08" for the butt cleat. Variations of coal cleat direction between coalbeds examined in strip-mined areas show similar values. Cleat orientations measured at outcrops agree well with the directions measured underground, suggesting that the amount of vertical separation between coalbeds has little effect on the resulting differences in cleat directions. The largest variation of cleat directions between adjacent coalbeds occurs where a large horizontal distance separates two sample locations. Cleat orientations for deeper coalbeds are most reliable where the data are taken from directly above.

Jan 1, 1976

By Frank C. Andreuzzi

The Division of Environmental Activities, U.S. Bureau of Mines, conducted a solid waste demonstration project on a burning coal refuse bank. The primary objective of this project was to develop and evaluate an efficient method of extinguishing burning coal refuse and moving it. A series of tests were performed using water monitors and related apparatus to quench the burning material and, at the same time, using earth-moving equipment to transport, spread, and compact the extinguished material. The method found to be most effective consisted of water-quenching the surface material to a workable depth, ripping, and removing the quenched material with a bulldozer and tractor-scraper. The total cost was estimated to be $0.44 per cubic yard.

Jan 1, 1970

By L. R. Burdick, R. Wiggers, J. F. Berkley

"INTRODUCTION On February 23, 1944, Solid Fuels Administrator Harold L. Ickes stated that the existing fuel shortage made it necessary to utilize a great surplus of freshly mined anthracite ranging in size from Barley (No. 3 Buckwheat) downward through the smaller sizes. As a part of the program to increase the use of such coal, field trials of mixtures of bituminous slack coal and anthracite Barley were made on industrial-size stokers at many fuel-burning plants. The following covers the test information it was possible to accu-mulate during the work of initiating the use of these mixtures at the plants.SUMMARY AND CONCLUSIONSField tests of various mixtures of bituminous slack coal and anthracite Barley on industrial-type stokers show that the use of such mixtures is very practicable and that it is possible to change and usually to adjust to an improved condition the characteristics of a fuel bed of eastern bituminous slack coal by the addition of proper amounts of anthracite. The improved uniformity of the fuel bed of single-retort stokers makes possible less manual attention to the bed. Air flow through the fuel bed is affected.Smoke is decreased. In general, the fly ash and also the unburned combustible in the fly ash and refuse are increased. Clinkering in the fuel bed is generally lessened. The peak-load carrying capacity of the stoker is definitely affected, usually adversely for the higher percentages of anthracite."

May 1, 1946

By E. A. Magill

The Bureau of Mines has begun a study of the copper resources of the Cascade Mountains of Washington. The program includes reconnaissance of mineralized areas and examination and occasionally limited exploration of deposits that are considered characteristic of an area. The Bureau of Mines believes that published information may assist industry in searching for new sources of copper. The Miners Queen is one of a few Cascade Mountain deposits selected for prelim¬inary exploration. The investigation was not planned to delineate the ore body. A diamond-drilling program was carried out at the Miners Queen mine in the summer of 1955. Five diamond-drill holes were completed, totaling 628 feet. Two 35-foot shafts were dewatered, and all accessible underground and surface workings were examined.

Jan 1, 1957

By O. C. Baptist

This report presents results of an investigation undertaken by the Bureau of Mines to determine the clay content of typical petroleum reservoir sands in Wyoming and the effect of clay content on the permeability behavior of the sands. These results should have significance in determining the feasibility of injecting water into the sands for secondary recovery and in estimating the probable damage incurred by these sands if invaded with filtrates from water-base drilling muds. The results of air-, brine-, and water-permeability determinations are given for reservoir sands in three Wyoming fields. The amounts of materials of "fine silt and clay size" (Wentworth scale) in the sands and the types of clay minerals present, as identified by X-ray diffraction methods, are also presented and discussed.

Jan 1, 1955

By Willard L. Hunter

The smelting of tin slags was undertaken at the Bureau of Mines Albany Metallurgy Research Center (AMRC) to produce crude columbium-tantalum ferro-alloy as a unit operation in the production of pure columbium and tantalum oxides or chlorides. Columbium and tantalum-rich alloy was prepared during short unrelated campaigns over a total period of 12 years. Tin slags from Malaya and the Congo (Geomines) were smelted. These slags were reduced by carbon in a small, single-phase, steel-making furnace} a larger three-phase, steelmaking furnace, and a three-phase, submerged-arc furnace, In all cases depleted slags were fluid and easily tapped from the furnace. However, unless diluted by iron additions, the metal product was a viscous, high-melting, heterogeneous mixture that could be removed from the furnace only by hand rabbling.

Jan 1, 1966

By P. G. Clites

A laboratory furnace was developed by the Federal Bureau of Mines for use in studying the interrelationships among variables associated with skull melting and casting high-temperature metals. Although additional work is necessary to determine the extent to which the information obtained by using this furnace can be extrapolated to larger furnaces of the same type, many casting characteristics of metals and alloys can be determined on equipment of this size. This furnace is a laboratory-size, consumable-electrode, skull-casting furnace equipped with a water-cooled copper ladle. The ladle, which is a tilt-pour or over-the-lip type, has a volume of approximately 30 cubic inches and provides up to 20 cubic inches of molten metal for castings. Castings of various reactive and refractory metals, including zirconium, titanium, hafnium, columbium, molybdenum, tantalum, and tungsten, have been produced. In addition, castings of iron, chromium, and copper have been made. The simplicity and versatility of the apparatus would make it useful to metallurgical laboratories preparing cast specimens.

Jan 1, 1961

By R. G. Nelson

The mechanical properties of low-hafnium, arc-melted, Kroll-process zirconium are presented. The effect of temperature on the ultimate strength, yield strength, proportional limit, elongation, hardness, Young's modulus, electrical resistivity, and impact strength are shown, The effects of cold work and annealing on the tensile properties, bend radius, and formability, as determined by cupping tests, are also given, Tensile properties are compared, in part, to those obtained on earlier graphite-melted zirconium and on crystal-bar zirconium. INTRODUCTION The commercial production of high-purity, low-hafnium bearing zirconium has been achieved, and this metal is becoming available for industrial use. However, there is little published information regarding the physical and mechanical properties of this product; and, since there have been many improvements in the production and arc-melting techniques of zirconium in the past 3 years, it was considered advisable to present the properties of the vastly improved zirconium representative of current production.

Jan 1, 1954

By George S. Koch

Several methods of calculating ore grades by diamond-drill sampling in the Homestake mine, Lead, S. Dak., have been evaluated by statistical analyses of assay data. The natural distribution of gold particles, partly masked through sampling and assaying procedures, is probably lognormal. As a consequence of the gold particles being clustered rather than randomly distributed within the ore bodies, (1) more mine samples are needed to obtain a specified precision of mean grade than the number predicted by the standard-error-of-the-mean law; (2) the variance of gold values is not inversely proportional to sample volume, and, therefore, small-diameter drill core yields samples nearly as good as larger diameter core; and (3) sampling at 5-foot intervals provides nearly as good results as sampling at shorter intervals.

Jan 1, 1971

By F. E. Diebold

The methodology for describing the geochemistry of elements in a coal seam have been developed. This has been applied to the Rosebud Coal Seam, which is an economically important member of the subbituminous coals of the Fort Union Formation in Eastern Montana. The method development has involved a detailed study of two popular techniques for determining the metal geochemistry of coal, namely, whole coal analyses and coal physical fractionation. The mathematically contrived element associations (whole coal analyses technique) and the element concentration trends in the float and sink fractions (physical fractionation technique) are considered to lead to only qualitative conclusions concerning the chemical associations of the elements in coals. Additionally, the processes taking place with the coal during low temperature ashing in an oxygen plasma are experimentally investigated and shown to be of sufficeint extent that the use of such low temperature ash for deciphering element geochemistry is questionable. The method developed in this study is a chemical fractionation that involves the sequential leaching of coal with water, 0.5 N HC1, 3 N HC1, 2 N HNO3, and 48% HF. These leach solutions are shown to selectively dissolve the predominate inorganic phases, sulfates, Ca and Mg carbonates, Fe sulfides and K alumino-silicates and quartz, respectively. These phases were identified with the use of XRD, SEM, EM and leaches (water and 0.3 N HC1) of whole coal and low temperature ash. The incorporation of the anion-exchange step in the leaching scheme was investigated and was observed to warrant further study of such intensity to be, at the time, unuseable. The use of this sequential leaching technique on several coal samples from the same seam generates element concentration trends that can be quantitatively interpreted with respect to the chemical associations of the minor and trace metals in the coal seam. The properties of the various seams of economic importance in the Fort Union Formation in Eastern Montana are compiled and presented. The subsequent conclusion is that there is not a large variation in the properties of these coal seams and that the variations within the Rosebud are within one order of magnitude. The chemical fractionation technique, investigated in this study, was applied to composite tipple samples of the Rosebud seam. Each composite sample represented 76,800 tons of coal. A minimum of 32% of the Ca and Mg are present as separate water soluble sulfates. An excess of the sulfate ion in the water extracts shows the predominating influence of the ion exchange capacity of the organic compounds in the coal. Based upon the CO content of the coal and the HC1 leachate data, 25 to 30% of the alkaline earth elements exist as separate carbonates and the remainder are associated with the organic compounds. The small fraction of the illite that dissolves in the HC1 and HNO3 leachates accounts for the K and Al. Slight dissolution of the pyrite in the HCl solvent occurs, the small amounts of Li and As do not relate to any known phase and Mn is present as a separate carbonate phase. Fe and a significant amount of the As exist in the pyrite that is dissolved in the HNO. Se is equally partitioned between the pyrite and the organic compound~. Most of the trace elements are found in the HF solutions. Li, V, and Cr were interpreted to be associated with the clay minerals (kaolinite and illite). Ni and Pb appear to be present as separate phases and 50% of the Hg is HF soluble but is not chemically related to any known inorganic phase.

Jan 1, 1983

By H. W. St. Clair

This study of the rate of evaporation of zinc was undertaken as a part, of a general investigation on refining mixtures of metals resulting from melting reclaimed scrap. One of the methods by which the more volatile metals, such as zinc, magnesium, and cadmium, may be separated is by distillation. Distillation may be carried out at lower temperatures if it is done in an evacuated enclosure. The immediate purpose of the present investigation was to determine accurately the effect of temperature, pressure, and other factors on the rate of evaporation of zinc.

Jan 1, 1950

By Don M. Coulter

"INTRODUCTION The district comprising Union, Lafayette, Pontotoc and Calhoun Counties, Miss. (fig. 1), was examined in October 1941 by R. W. Smith of the Bureau of Mines, accompanied by J. W. Adams of the Mississippi Bauxite Co. 3/ Subsequently, geologists of the Federal Geological Survey made a more detailed study of the area. 4/Bauxite had been reported as present in several localities in Pontot. County, and large deposits of kaolin are known in Pontotoc, Union, Calhoun, and Lafayette Counties. Many of the bauxite deposits, such as those on Big Hill, Second Hill, and Third Hill, in Pontotoc County, form the caps on hills and are outliers of Wilcox deposits on the Midway formation. Such deposits could have no extensions because of erosion and were not examined, as they were investigated by the Mississippi Geological Survey. 5/ Most of the bauxite was known to be low-grade, with a high iron content. However, Pontotoc County in particular presented possibilities of finding high-grade bauxite with a low iron content by drilling down the dip from the Wilcox-Midway contact. Consequently, with few exceptions the investigation was confined to drilling in this direction.Headquarters were established in Tupelo, Miss., on July 13, 1943, and mineral agreements were obtained covering 8,367 acres of land, with 62 land-owners in Pontotoc and Union Counties. Holes were drilled on properties of three of the landowners in Union County and 36 in Pontotoc County."

Apr 1, 1948

By C. E. Armantrout, H. Kato, M. I. Copeland

The data collected during this investigation indicate that the chromiumgadolinium system has extensive liquid immiscibility and one eutectic point . Liquid immiscibility occurred at temperatures above the monotectic isotherm , 1,830 ° C , which extended from less than 0.25 to about 85 weight - percent gadolinium . The eutectic was at 96 percent gadolinium and 1,170 ° C. Gadolinium and chromium were the only phases in this system . There was a solid solubility of less than 0.25 percent gadolinium in chromium at 1,730 ° C and less than 0.10 percent chromium in gadolinium at 1,160 ° C. The alloys were prepared by nonconsumable - electrode arc - melting , and the alloy system was investigated by heat treatment , metallography , thermal analysis , and X- ray diffraction . All the melting , heat treatments , and thermal analyses were conducted in a vacuum or in helium because of the reactivity of chromium and gadolinium with the components present in the atmosphere at elevated temperatures .

Jan 1, 1964