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By George E. Fish

This report describes investigations conducted by the Bureau of Mines from 1957 through 1959 in the Roseland anorthosite-titanium belt of Nelson and Amherst Counties, Va., for the purpose of studying the titanium resources of the area. Three titanium deposits containing much saprolite ore derived from the decomposition of anorthosite and diorite were selected for detailed study Following a reconnaissance of the reported titanium occurrences in the belt. These three deposits occur in or are associated with anorthosite. Most of the occurrences are situated on or near the contact between the anorthosite and the gneissic country rock. The saprolite deposits are as much as 1.5 miles long, 1,000 feet wide, and 100 teat deep and contain significant reserves of titanium-bearing material estimated in excess of 20 million tons. Where it was penetrated by drilling, the unweathered rock beneath the saprolite contains nearly the same titanium values as the saprolite.

Jan 1, 1962

By Jack O. Jones

The Furnish mine, Caharrus County, W. C., was operated intermittently until 1905 as a gold mine. Scheelite was discovered by A. L. Mash in the mine dumps of the Furniss and Phoenix mines, and he later informed the Bureau of Mines of his discovery. The Bureau of Mines, in two projects at the deposit in 1948 and in drilled 12 holes totaling 1,706.6 feet, examined and sampled the underground workings, excavated by bulldozer and hand, 3,155 linear feet of trenches and collected numerous samples for assay. The best scheelite shown; was found in the underground exposure of the Furniss mine.

Jan 1, 1950

By Richard A. Dick

Eight blasts were fired in a 2-1/2-ft bench in the Stewartville member of the Galena Limestone formation in an aggregate quarry near Stewartville, Minn. The shots were dimensionally proportional to production-size bench blasts and were about 5 to 10 percent of full scale. The effects of site, timing of initiation, and burden-to-spacing ratio were studied in a 2 x 2 x 2 factorial experiment, using three boreholes, caw;, containing a 1/2-in charge diameter of high-density ammonia dynamite, in each blast. Detonation velocity measurements indicated that the dynamite detonated satisfactorily in the 1/2-in charge diameter. The effects of the three experimental variables were analyzed by weight for the percentage of oversized material produced and for size distributions determined by screening the entire muckpiles. The bench faces were painted before each shot in an effort to determine the origin of the oversized material. The square pattern (burden and spacing = 15 in) produced finer overall fragmentation and less oversized material than the rectangular pattern (burden = 15 in; spacing = 22-1/2 in). Sites 1 and 2 were about ft apart. Although site 2 produced slightly better overall fragmentation than site 1, the amounts of oversized material produced showed no significant difference. The timing of initiation (instantaneous or delayed) did not significantly influence the overall fragmentation or the amount of oversized material produced.

Jan 1, 1973

By J. Cseff

A variety of shaft and hoist equipment exists in the United States. Nearly all hoist systems are electrically driven. Machine elements which comprise the hoists and ancilliary equipment include bearings, shafting, drums, gear reducers, couplings, brakes, clutches, sheaves and electrical motors. Volume I, Systems Description, describes the various components encountered in most mine hoist and shaft installations, and brief descriptions of functions and constructions. Hoist ropes and balance ropes are specifically excluded from this report. Associated with the hoisting system is the headgear, shaft and equipment, loading/dumping facilities and the actual conveyances and their rope attachments. Volume II, Inspection and Maintenance Procedures, discusses scheduled Inspection and preventative maintenance in general terms. Preventive scheduled inspection and maintenance procedures assist in the smooth operation of mine hoisting plant, by the prevention of unscheduled or catastrophic equipment failure and its attendant downtime. Schedules and overall maintenance planning is required at the management level. Records and equipment logs must record inspection and maintenance, and unusual operations or incidents. A cross reference between MSHA regulations and various equipment components is included as part of the report. A discussion of the various non-destructive testing methods which may be applied to hoisting equipment is also included.

Jan 1, 1981

This report describes the development, installation and performance of a lonpwall illumination system. The longwall illumination system was installed at the Greenwich Collieries 112, Cockport, Pa. It utilized flourescent luminaires, intrinsically safe power distribution and is the first longwall system installed in Pennsylvania.

Jan 1, 1976

By James W. Myers

The Bureau of Mines studied factors affecting ignition of coal mine refuse and on methods for control of burning. Laboratory experiments showed that air permeates more readily through segregated than through nonsegregated refuse and that air permeability is greater through coarse than through fine particle refuse. Minus 3-1/4-inch refuse ignites spontaneously more readily than minus 1/4-inch refuse. The burning of a 1,000-pound conical coal pile was con-trolled by capping with an 18-inch-thick layer of minus 1/4-inch refuse containing 37 percent combustible. In field trials, the burning of refuse at operating mines was controlled by capping with a layer of fine refuse. Water, applied as a spray or by injection, quenched surface flames and cooled the burning waste. Inspection of refuse piles at operating mines showed that the spontaneous ignition tendency is affected by the exposed surface relative to the total volume and the segregation of particles during dumping.

Jan 1, 1966

By Paul M. Ambrose

ADVANCES in mining and processing technology made it possible to reopen the De Beers diamond mine in South Africa, originally located in 1871 by Cecil Rhodes and closed in 1908. Radioactive material was used to indicate the efficiency of hydro-cyclones used in diamond concentration. Added interest was shown in recovering diamond from the sea off the coast of South-West Africa. Production of crude artificial abrasives declined because demand was paritally met by withdrawals from stocks. The value of graded grain-coated abrasives and grinding wheels surpassed those of 1962.

Jan 1, 1964

By Scott W. Hazen

METHODS of determining the grade and tonnage in a mineral deposit have not kept pace with scientific developments in certain other fields. The most commonly used methods of computing ore reserves and grade based on diamond-core-drill sampling are the cross section, the polygon, and the triangle. Tonnage and grade may be determined by these methods with acceptable accuracy, providing a sufficient number of samples is obtained; however, there is no means of determining when an adequate number has been taken or conversely if the deposit has been sampled excessively. It is demonstrated that, by using the techniques of statistical analysis, a mining engineer will be able to determine when a sufficient number of samples has been taken to determine the grade of a mineral deposit within a specified degree of confidence. Using statistical analysis to compute the estimated average grade of the ore makes it possible to compute a fiducial interval, when a distribution of the sample means is normally distributed, so that there is 95-percent confidence in the statement that the true average grade of the deposit is covered by the interval. This report utilizes data obtained from the Maggie Canyon manganese deposit, Artillery Mountains region, Mohave County, Ariz. Four separate exploration projects were conducted at Maggie Canyon between 1936 and 1950. Present economic conditions have made it desirable to determine the amount of 5-percent manganese ore developed by these projects.

Jan 1, 1957

By R. V. Ramani

This volume is the fourth of a four-volume final report on research carried out under a contract from the U.S. Bureau of Mines on the development of a computer simulation model for surface mine reclamation planning. The other volumes are titled as follows: Volume I: Ore Reserve Estimation, Volume II: Dragline Model, and Volume III: Mine Coordinate Generator System. The Open Pit Materials Handling Simulator (OPMHS) was first developed" in 1971 and modified and updated in 1975. The present work is an update of the 1975 version and provides a direct link between the geology and reserves system and the various activities of the mining equipment in a mining system. Also, the modeling techniques in OPMHS/2 have incorporated a flexible method for describing various equipment (shovels, trucks, belts, trains, etc.), locations, their sequence of operations, place changes, and their interactions. These features allow for studying mining equipment selection, mining method analysis and reclamation planning. This report describes the Open Pit Materials Handling Simulator Version 2 (OPMHS/2). The report details the program features, operation, and application. Through an extensive set of appendices, the data input sequence, input variable definitions, sample data listing and program output are presented in detail.

Jan 1, 1985

By Alfred L. Ransome

GOLD output in Alaska in 1950, following a 2-year decline, increased to the highest point since 1942. Tills unexpected gain in production of the Territory's greatest value commodity was largely responsible for the increase in the over-all value of mineral output in the Territory to $17,852,000 from $15,549,000 in 1949. Although coal continued to rank second to gold in value of output, production was slightly less than the record production of 1949. The mining of platinum continued to be an important factor in the mineral industry, with production of crude platinum metals exceeding that of 1949. The output of lead was three times the 1949 production, and silver gained 46 percent over the previous year's total. Copper and zinc production-entirely as byproducts from other ores-showed an increase, but remained minor. Production of tin was relatively small, but substantially above the total for 1949.

Jan 1, 1953

By Jos. R. Guiteras

This paper describes the pumping operations at the Ajax, Cresson, and Vindicator dines in the Cripple Creek mining district of Colorado during the summer of 1936. At that time the three mines wore pumping 6,500 gallons of water per minute into the Roosevelt drainage tunnel. Cripple Creek is the most important gold district in the State; it has yielded gold valued at over $365,000,000. The mines engaged in pumping are among the largest producing properties in the district. ACKNOWLEDGMENTS The author wishes to acknowledge the friendly cooperation of mine officials at the properties visited. At the. Ajax mine information was courteously given by Clayton Kissel, mine superintendent, and his staff; R. Y. Roby contributed the drawings. For information on the Cresson mine, thanks are expressed to Al H. Bebee, mine superintendent, and his staff, especially to Guy Rorabaugh, master mechanic, and to engineer Carlton. At the Vindicator mine, J. S. Anderson; mine superintendent, and Robert Welch, master mechanic, assisted; the latter furnished most of the information about that mine. Acknowledgment is also made of the cooperation of M. H. Salsbury, engineer at the Portland mine, who supplied technical data on the Roosevelt drainage tunnel.

Jan 1, 1937

By S. H. Ash

The Pennsylvania anthracite region is composed of four fields, namely, the Northern, Eastern Middle, Western Middle, and Southern. It is in the eastern part of Pennsylvania and is shown on figure 1. The anthracite industry is confronted with a crucial problem of inundation by water impounded in underground pools in many mines and by infiltration of water from streams and pools on the surface (3). The deposits of anthracite in the United States are limited virtually to Pennsylvania, and the difficulties of this industry have been commonly considered as a State problem rather than a national one (1, 4, 6, 7). Anthracite was discovered in Pennsylvania in 1762, and the first mining company was formed in 1793. It was not until 1812 that anthracite began to receive recognition in the Philadelphia market as a domestic fuel, and by 1838 the annual production was nearly 1 million net tons. Since anthracite mining began, mine water has become progressively more difficult and costly to handle because of the extraction of anthracite both underground and along the outcrops of the beds, until at the present time mine drainage is a major anthracite-mining problem. Mine water is handled at the anthracite mines as follows: (a) by pumping, (b) by drainage tunnels, (c) by combination of pumping and drainage tunnels, and (d) by water hoists (hoisting water by means of large buckets) (4, 5,6, 7). This paper covers removal of the water from mines by means of pumping plants. Pumping is indispensable in the production of anthracite (5). The cost of pumping mine water has increased progressively since anthracite mining began. Some collieries have been forced to discontinue mining because of the high cost of pumping.

Jan 1, 1950

By J. A. Cooper

The objectives of this research were to define the chemical composition and physical characteristics of the aerosols associated with attached radon daughters in operating uranium mines, and to investigate the relationship between these aerosol parameters and operating conditions. Major Results and Conclusions The organic, inorganic and radiological characteristics of test chamber and active U-mine aerosols have been measured as a function of particle size. These measurements represent the first detailed analyses of the organic and inorganic components in U-mine aerosols and the first determinations of the details of the individual and total radon daughter distributions in operating U-mines. The following is a list of the major results and conclusions:

Jan 1, 2012

By C. W. Owings

"Ventilation is one of the most important features of coal mining, and if a mine is exceptionally gassy it is often difficult to ventilate it in such a way as to make it safe. The general system of splitting the main air current so that two, three, or more sets of room entries are ventilated by the same current of air does not provide a safe method if non-permissible electrical equipment, such as cable-reel, crab-reel, or trolley locomotives are used on gathering haulage, or if open-type hoist or pump motors are used. The problem has been greatly simplified at the Crucible mine of the Crucible Fuel Co. at Crucible, Pennsylvania.The system is not only applicable to the room-and-pillar method of mining, but it may be adopted for any panel system of mining. There also appears to be a definite application in mechanized mining, where the rapid extraction often results in inadequate attention to ventilation and where the gassiness of the section generally increases because, as compared to hand loading, the methane has less time to drain off. The system to be described should commend itself to coal-mining men.ACKNOWLEDGMENTSThis investigation was made possible through the courtesy of H. J. Nelms, general superintendent. E. M. Marshall, safety inspector, E. G. Sauers, assistant superintendent, and Thomas Mark, mine foreman, assisted in the collection of information."

Sep 1, 1931

By Ernest A. Curth

Statistics For 1956-66 show that mine transportation accidents accounted for 19 percent of fatalities in bituminous coal mines, second only to roof deficiencies as a cause of death. Productivity per man-shift increased from 10.2 tons in 1956 to 18.4 tons in 1966, but the fatalities per million man- hours of exposure also increased from 0.19 to 0.21 during that same period, indicating that transportation hazards still persist. Consequently, the Bureau of Mines reviewed the transportation fatalities that occurred in bituminous coal mines during 1956-66. The data were processed by computer to find what constitute hazardous conditions and unsafe actions as well as to correlate occupation and age of victims, transportation type, and mine production. Environmental factors and equipment defects which create hazards, as well as unsafe actions of personnel, were determined for each type of mine transportation: Track haulage, mobile nonrail haulage, conveyors, hoists, automotive operations, and front -end loaders, and for transfer stations (loading points, slope and shaft bottoms, surface transfers) and railroad yards. Man-trip accidents, a group with a catastrophe potential, also were analyzed. The basic design and operational features of each transportation type were outlined and procedures considered safe in the light of accident experience were suggested. Findings show that unsafe actions of personnel and hazards created by environmental deficiencies or equipment malfunctions contribute equally in causing transportation accidents. Accordingly efforts should be directed toward improving working conditions, equipment maintenance, and education and training of employees. The trend is toward using safer modes of transportation, notably conveyors. More attention should be given to track haulage operation, railroad yards, and nondestructive field testing of materials.

Jan 1, 1971

By A. J. Barry

This report presents observations made by Bureau engineers regarding hydraulic-powered roof supports that are currently being used or have been used on nearly all operating longwalls in the United States, A comparative summary of specifications for various types of powered supports with a brief description of the mine conditions has been compiled to enable mining engineers and mine operators to readily evaluate the differences in design data. Some of the support data furnished in the field may vary from those listed in manufacturers' brochures because of the trend to customize various support components to meet specific mine conditions. A method of estimating support requirements for different assumed operating conditions is presented. Similar computations for specific mine conditions may be used to make preliminary estimates of support requirements.

Jan 1, 1969

By Forrest T. Moyer

Need for lightweight building materials was created in the latter part of the nineteenth century by a radical change in building design in which dead load or structural weight was transferred from thick, heavy, load- bearing walls of former construction practice to a load-carrying framework of beams and columns with thin walls. This new design was brought about by the introduction of structural steel followed by reinforced concrete and structural concrete as materials for the erection of the load-supporting frame. The new materials and method of construction made possible the erection of skyscrapers and the building of bridges with long spans, and made feasible additions of one or more floors to existing buildings. As size and design of the load-bearing framework are controlled chiefly by dead load, the natural result was a. search for and use of light- weight materials in partitions, floors, and exterior walls. However, these thin walls created problems of heat and sound. insulation, so that building materials which possessed good heat- and sound-insulating properties in addition to light weight were objects of extensive research. One group of materials developed to fill this need comprised lightweight concretes, of which some were obtained by the use of lightweight aggregates. Although the advantages of lightweight.materials were evident from the first skyscrapers, there was a transition.stage.between the old bearing- wall and modern skeleton-frame types of building, with the heavy and massive construction of the former superimposed upon the latter. Hence, it was not until the period between 1910 and 1930 that the new lightweight concretes were recognized and used more extensively in the erection of large, nonresidential buildings. From this type of construction, light- weight-aggregate concretes entered-fields of residential and small non- residential building; in which they were found desirable for production of prefabricated, large-size; masonry units. Although the weight of each unit was reduced sufficiently to enable one man to handle it easily, properties of the new concretes other than light weight were the principal factors in the ready acceptance of these new materials in residential building. Manufacture of precast units includes complete lines of masonry and back-up blocks, bricks; floor beams, columns and partition, roof, and floor tiles and slabs. Recent improvements in casting machinery, development of the vibration-pressure machine, and a more thorough study and knowledge of the requirements and properties of the concrete mix have all contributed materially to the rapid expansion in use of lightweight aggregates in this industry.

Jan 1, 1942

By H. M. Thorne

The oil-shale deposits of the Puertollano basin in the Spanish province of Ciudad Real appear to have been give little consideration in discussions of oil-shale resources throughout the world. A small, integrated oil-shale operation has been conducted at Puertollano since about 1922 by a French company, Sociedad Mimora y Metalurgica de Penarroya, hereinafter referred to as "Penarroya", but only within recent years have the potentialities of the Spanish oil-shale deposits been recognized. Empresa Nacional "Calvo Sotelo" do Combustibles y Lubricantes, hereinafter designated as "Calvo Sotelo," which was created in 1942 by the National Industrial Institute of Spain to produce liquid fuels from oil shales, has made marked progress in the design and construction of a complete oil-shale plant at Puertollano. Penarroya is mainly a coal-mining company, and the oil-shale operations were on a small scale of approximately 220 tons a day in October 1947. It is an integrated operation comprising oil-shale mining and retorting and shale-oil refining. Motor gasoline, Diesel fuel oil, light burner fuel oil, lubricants, paraffin wax, cresols, and ammonium sulfate are manufactured.

Jan 1, 1950

By K. E. Stanfield

Oil-yield results are presented for 65 oil-shale sections in Piceance Creek Basin, Colorado, sampled during the period 1957 through 1963. Including previously published data, oil-yield results for 203 sampled sections have now been released by the Bureau of Mines to aid in appraising the shale oil potential of the basin. Oil yields of core samples (135 sets) were regarded as reliable bases for appraising the Mahogany-zone interval, but only 5 sets of cores sampled the deeper, lower-zone oil shales. Drill cuttings (68 sets) sampled the lower-zone oil shales, but their oil yields are principally indicative and should be confirmed by analyses of cores. More complete core sampling of the lower-zone oil shales is needed.

Jan 1, 1967

By Homer J. Ballinger

During the fall of 1943 and spring of 1944, the Bureau of Mines investigated nine secondary limonite iron-ore deposits in the Williamsville district of Wayne, Butler, and Ripley counties, Mo., by rotary-bucket and power-auger drilling test pitting, and trenching. Studies on beneficiating the ores were made at Bureau laboratories. Iron ore has been mined in Missouri since 1825, and iron mining reached its greatest development between 1870 and 1890. During this period, production averaged about 250,000 tons annually.

Jan 1, 1948