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By Ralph H. Whaite

The Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region is described. A catalog of the maps that have been microfilmed in the Eastern Middle anthracite field--the first area to be covered in the program--is presented. Additional catalogs will be published as significant mining areas are completed.

Jan 1, 1965

By Ralph H. Whaite

The Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region is described. A catalog of the maps that have been microfilmed in the Eastern Middle anthracite field--the first area to be covered in the program--is presented. Additional catalogs will be published as significant mining areas are completed.

Jan 1, 1965

By S. C. Termes

The Bureau of Mines has used Fourier transform infrared spectroscopy (FT-1R) to study in situ reactions of aqueous solutions of potassium ethylxanthate with CU(II)-and Pb(II)-activated sphalerite plates, in which the plates were both the infrared-transparent windows and the reacting surfaces. A copper (I) ethylxanthate formed predominantly with Cu(II)-activated sphalerite, regardless of the activation time. The products formed on Pb(II)-activated sphalerite depended on the activation times; a short activation time (30 min) yielded a lead ethylxanthate-like product, but a long activation time (90 min) yielded a considerable amount of dixanthogen.

Jan 1, 1986

By Eric R. Bauer

The ground control aspects of extended depth-of-cut mining are presented in this U.S. Bureau of Mines report. A trend analysis of extended cut approvals was performed. A comparative review of roof fall fatalities for extended and nonextended cut mining is included. Current ground control guidelines for extended cut approval are summarized. The problems and concerns of this extraction system are addressed, and typical extended cutting face operations are described.

Jan 1, 1993

By A. B. Hooker, E. J. Coggeshall

"INTRODUCTION Ignitions of gas at the coal face when a blast is fired electrically are often a tributed to the explosive; but sometimes the ignition cannot be explained satisfactorily in this way-in fact, ignitions have occurred when the detonator has failed explode.The possibility of such electrically by sparks from the blast between poorly insulated leading wires and detonator leg have been recognized. Several countries have provided safe types of single-shot blasting units; some have permitted the use of larger multiple-shot blasting units provided each unit is equipped with a time-limiting switch that prevents unnecessarily long application of voltage on the leading wires after the shot has occurred, the assumption being that the firing line will this be dead before damage to the wires and subsequent sparking can take place. An extensive research was made by a French commission relative to the characteristics of electric detonators and methods of firing. Along other tailings they investigated the probability of ignitions by sparks across the leading wired at the face, also the time and duration of the various events in blasting, such as ignition of the detonators, movement of the coal face, and application of firing current. They suggested, as a means of eliminating or reducing tilt possibility of gas ignitions from the blasting unit, that the timing switch of the blasting unit be designed to disconnect the blasting"

Oct 1, 1934

By F. S. Crawford

Mining companies are usually held responsible for accidents occurring to the public around their operations . Safeguards are provided by progressive mining companies to prevent the public from getting into danger from wandering unattended about the properties . At abandoned operations , where little or no supervision can be maintained , persons are often injured through the negligence of the operator in leaving the property in unsafe condition . After a mine is abandoned or a lease is given up by a mining company , the responsibility for the safety of the property rests sometimes with the State to which the property ownership reverts or with the owner of the land ; either is usually quite unwilling to spend any money to remedy unsafe conditions due to the carelessness of the mining company . The land owner or the State , or both , should see that the work of leaving safe conditions behind is done by the operator before he abandons the mine or gives up the lease . Some of the worst hazards to the public at abandoned mines are from old test pits , abandoned shafts or tunnels , open pits , caved ground , and bodies of water in abandoned open pits . Hazards exist from some of these sources during the active operation of a mining property as well . In the early stages of mining operations test shafts are often sunk from 50 to 100 feet deep through the more or less loose material overlying bed rock . When these shafts are left unprotected , they are a serious danger for many years to come . In the course of time they become largely concealed by brush and grass , and thus are a deadfall to anyone who might happen to step into them . This condition will hold true for any part of the country, but to a much less degree where it is not necessary to sink through a great amount of cover . Many progressive operating companies have adopted the practice of filling in test pits after securing the information desired . Some nonresident landowners and exploration companies , however , have left such pits open , and it is extremely difficult for the mine inspector to get into communication with the owner . Frequently operating companies voluntarily fill test pits on adjacent property not

Jul 1, 1930

By D. H. Baker

THIS REPORT presents the technique and equipment used in determining the hardness of titanium sponge. Detailed descriptions are given of the methods used in preparing test samples for chemical analysis and hardness testing, the method of melting and surfacing test ingots, and the technique of reading Brinell-hardness impressions. The arc-melting furnace described, for which engineering drawings are included, will produce from 70 to 90 double-melted buttons each 8 hours of operation. Experimental data are also presented depicting the effect on hardness of the methods of surfacing specimens, temperature of test specimens, and the effect of time at test load. These data show that surfacing of the specimen involves no critical machining operations but that the test surface must be paralleled by a relatively flat surface for contact with the anvil of the Brinell tester. The heating of a specimen to 150° C. during surfacing does not materially affect the results if the ingot is cooled to room temperature before the hardness impressions are made. The optimum time at load appears to be approximately 30 seconds, but load times of as much as 1/ ½ minutes will not cause major errors.

Jan 1, 1959

By J. P. Coughlin

The U.S. Bureau of Mines has developed a monitoring system that acquires and analyzes data for use in determining the conditions that may precede mountain bumps in coal mines. Based on a UNIX workstation linked to an array of geophones in a working longwall operation, the system captures complete waveforms of microseismic events and simultaneously obtains continuous samples of the voltage levels of each geophone. Event rates and locations are calculated and displayed in real time on the UNIX workstation, which is situated in an underground instrumentation room. These results also are transmitted from the workstation to a display computer near the longwall face. The system runs continuously and has the capability to acquire, analyze, display, and archive microseismic (transient) data and single point data, such as closure and pressure changes, simultaneously.

Jan 1, 1993

By E. M. SEELEY, F. S. LOTT

The total capacity of the natural-gasoline industry to produce light hydrocarbon products increased to 21,322,000 gallons ( 507,670 barrels ) daily on January 1 , 1948 , from 17,928,000 gallons ( 426,860 barrels ) daily on January 1 , 1946. Expansion of the industry in the first two post -war years , 1946 end 1947 , thus averaged 9 percent annually , compared with 6 percent annually in the last two war years , 1944 and 1945 . The number of cycle plants increased only from 37 to 39 in the years 1946 and 1947 , and total capacity of these plants gained 21 percent to 5,857,000 gallons de ily on January 1 , 1948 , represent ing 27.5 percent of the total capacity of the industry , compared with 27.0 percent on January 1 , 1946. All other plants decreased in number in the two-year period from 589 to 510 on January 1 , 1948 , but their total daily capacity increased 18 percent to 15,465,000 gallons . The daily capacity of the average plant in the industry was enlarged from 28,600 gallons on January 1 , 1946 , to 38,800 gallons on January 1 , 1948 , continuing the long -established trend to producing units of greater size and efficiency . The average cycle plant capacity increased from 131,000 gallons daily to 150,200 gallons daily on the same dates as the average capacity of all other natural -gasoline plants increased from 22,200 gallons to 30,300 gallons . Owing to the elimination of small , obsolescent plants in Illinois , Oklahoma , and Pennsylvania , these States experienced the greatest reductions in numbers of plants in 1946 and 1947. In Oklahoma and Texas , several consolidations of two or more plants into a single operating unit were reported . Louisiana and Mississippi were the only States in which the number of plants increased , but daily capacity to produce light products was larger in eleven States on January 1 , 1948, than two years earlier . Added facilities in California and Texas accounted for 41 and 36 percent , respectively, of the national gain in capacity .

Sep 1, 1948

By Paul T. Allsman

The Salt River range vanadium deposits are situated 3 to 6 miles east and southeast of Afton, Lincoln County, Wyo. The vanadium occurs in a continuous bedded shale zone of the Phosphoria formation extending from the vicinity of Afton into southeastern Idaho. The Bureau of Mines explored several of these vanadiferous-shale deposits between December 1942 and December 1943 and conducted metallurgical tests on the ores. The areas investigated were west Swift Creek, the Dry Creek, and the Cottonwood Creek. The vanadiferous-shale beds have been folded sharply into a series of tightly compressed, eroded anticlines and synclines, which form the Salt River range. The vanadium occurs in a series of narrow shale or mudstone beds contained within the phosphatic-shale member of the Phosphoria formation. Exploration by the Bureau of Mines consisted of surface trenching and underground work over 18 miles of outcrop of vanadiferous shale with an average assay value of 0.866 percent V2O5.

Jan 1, 1949

By H. B. Humphrey, F. E. Cash

The following information on accidents in Alabama during 1930 was compiled from data obtained from the companies represented in a course on accident prevention given by the United States Bureau of Mines in Birmingham. These mines produced nearly three-quarters of the tonnage of that State for the year, and included most of the larger operations in the district. The figures are probably representative of the mines which are doing recognized safety work, and are better than the average for all the mines in Alabama. Table 1 lists the days lost in accordance with the weights given to fatalities and permanent disabilities, part and total, which is the scale used in the National Safety Com¬ petition for Mines, conducted by this bureau. By way of explanation, temporary disabilities are weighted according to actual number of calendar days of disability, including Sundays and holidays — that is, all days are counted except the day of accident and day of employee's ability to return to duty. Hernia is classed as a temporary disability to be charged with the actual number of calendar days during which the employee was unable to work. Table 2 gives the number of accidents and the days lost from each cause at 45 coal mines and 7 iron ore mines, also the average frequency and severity rates.

Aug 1, 1931

By D. W. Frommer

Mineral dressing research was conducted by the Federal Bureau of Mines under a cooperative agreement with the St. Joseph Lead Co., on three samples of iron ore from the Pea Ridge deposit in central Missouri. The objective was to provide information on how to upgrade these submarginal ores and produce marketable concentrates. Samples were prepared from drill-hole cores of similar composition and character to produce (1) a medium-grade mixed hematite and magnetite, (2) a high-grade mixed hematite and magnetite, and (3) a high-grade magnetite. In all three ores phosphorus and sulfur constituted objectionable impurities; excessive amounts of silica were also present in the medium-grade ore.

Jan 1, 1960

By E. J. Kloos

One phase of the work of the Bureau of Mines in health and safety is promoting the use of safe, satisfactory, and reliable respiratory-protective devices. To insure that such devices will be available, the Bureau has established schedules of minimum-performance requirements for the approval of self-contained breathing apparatus (1),4/ gas masks (2), supplied-air respirators (hose masks, air-line respirators, and abrasive-blasting helmets, hoods, or masks) (3), dispersoid (dust, fume, and mist) respirators (4), and nonemergency gas respirators (chemical-cartridge respirators) (5). Approval tests of self-contained breathing apparatus are conducted by Health and Safety District B; approval tests of other types of respiratory-protective devices are conducted by the Branch of Health Research. Manufacturers of respiratory-protective devices may submit their equipment to the Bureau of Mines for approval under the requirements of these schedules. If the device, when tested by the Bureau, meets the schedule requirements, a certificate of approval will be granted, which not only states that the equipment has passed the schedule requirements but also gives information about the limitations of the device. If it is found at any time that approved devices do not meet the requirements of the pertinent schedule, the Bureau may rescind approval.

Jan 1, 1959

By McHenry Mosier

The application of diamond drills for blast holes is limited to the special Job of extracting floor and stope pillars, and therefore their operation is intermittent. The zinc ore drilled occurs in metamorphosed dolomitic limestone. The mining method is sublevel open-stoping on 200- foot lifts. Ample fresh air is provided by mechanical ventilation. Diamond drilling blast holes began in August 1944. Drills were mount- ed on a 3-inch quarry bar. The contract price for labor for operating equipment owned by the company was $0.23 per foot. The diamond bits were cast-set at the factory in a sintered tungsten matrix. Bit replacement costs were $0.15 to $0.20 per foot drilled. The feet drilled per bit ranged from 87 to 258. The feet drilled per diamond-drill shift ranged from 121 to 129. Holes were loaded with 60-percent special gelatin dyna- mite and fired electrically. In percussion drilling, the estimated feet drilled por machine shift with hand-held sinkers was 65. The tons broken per machine shift averaged 40 throughout the mine. Detachable bits have been adopted recently. The principal advantage of diamond-drilling blast holes at the Balmat mino is the extraction in a safe manner of ore not minable by short-hole drilling. The principal disadvantago is the greater cost per foot of holo in comparison with percussion drilling.

Jun 1, 1947

By R. W. Geehan

The Yellow Pine zinc-lead mine, situated about 3-1/2 miles northwest of Goodsprings, Clark County, Nev., was explored by core drilling during the fall of 1942 and the summer and fall of 1944 by the Bureau of Mines in cooperation with the Federal Geological Survey. The Yellow Pine district was located in 1855. The original claims covering the Yellow Pine mine were located in the following years: Rover, 1892; Hilo, 1897; Bybee, 1900; Radio and Como, 1906. The mine was operated by the Yellow Pine Mining Co. from 1906 to 1929. This company was dissolved in 1935. At a later date, S. E. Yount and the Security First National Bank of Los Angeles, Calif., acquired ownership of the mine. Since 1939, the mine has been operated in a small way by leasers. Production has been at least 175,000 tons averaging about 10 percent lead and 25 percent zinc, with a gross yield of $5,785,174. Virtually all ore produced by this mine consisted chiefly of oxidized zinc and lead minerals and came from long, pipelike shoots in the 100-foot thick Yellow Pine limestone. Ore shoots are sharply defined; elsewhere, the limestone is nearly barren. Numerous faults cut the mine into blocks. Ore is now mined in an open stope, but in the past, large tonnages wore mined in stopes by square-set methods. Ore produced recently was shipped direct to smelters unprocessed; in the past, it was milled by gravity and produced separate lead and zinc concentrates.

Jan 1, 1949

By Jr. Gabler

World resources of cobalt appear ample for the foreseeable future; however, political and economic events have caused concern over the availability and reliability of an uninterrupted supply. Because of this concern, the U.S. Congress requested that the U.S. Bureau of Mines initiate a study of the flow of cobalt in the economy that would delineate and quantify the production areas where metal values are lost. As a result, the Bureau has developed a computerized commodity flow model. A major attribute of this model is that it is amenable to updating as supply, demand, and/or production data change. This report follows the flow of cobalt through its metallurgical and chemical applications and highlights areas where significant losses occur due to downgrading, export, or disposal. The study indicates that about 4,300,000 lb of cobalt-bearing materials are lost each year, representing 24 pct of U.S. domestic demand.

Jan 1, 1990

By G. W. Jones

[As a part of its investigations pertaining to the promotion of safety, the Bureau of Mines is investigating various means, useful for the elimination or mitigation of the explosion hazards of combustible gases encountered in mining and industry. Information has been obtained and a procedure developed whereby the explosibility of many complex, gaseous, combustible atmosphere may be calculated in a simple manner without the necessity of performing laborious laboratory experiment. In a previous publication4/ data were given and a method described whereby the limits of inflammability of gaseous mixtures, including methane, hydrogen, carbon monoxide, nitrogen, carbon dioxide, and oxygen, could be determined by calculation. The information published in that retort enables one to calculate the limits of inflammability of such gases are liberated by mine fires, gases from explosives, automobile exhaust gas, gases present after mine explosions, blast-furnace gas, and other gases containing part of or all of the above-listed constituents.]

Jan 1, 1938

By T. E. Green, E. F. Spano, W. J. Campbell

A combined ion exchange X- ray spectrographic method was evaluated for the determination of 11 metallic elements in high - purity tungsten : Aluminum , calcium , chromium , cobalt , copper , iron , magnesium , manganese , nickel , titanium , and zinc . Copper , nickel , and manganese in the 5- to 100 - microgram range ( 1 to 20 parts per million based on 5 - gram samples of tungsten ) , calcium in the 10- to 100 - microgram range , and cobalt in the 5- to 20 - microgram range can be determined within an accuracy of ± 10 percent of the amount present . Limits of detection of these elements are 0.05 to 0.14 microgram . The overall method was unsatisfactory for the determination of aluminum , chromium , iron , magnesium , titanium and zinc in tungsten .

Jan 1, 1964

By Arno C. Fieldner

Coal for coke production is fundamentally necessary for the manufacture of pig iron , and pig iron must be had for making steel - a vital element in our modern industrial economy . In both World Wars , special effort by Government and industry was required to meet the emergency of greatly increased demands . In the first World War , lack of coke - oven capacity , rather than lack of coking coals , was the principal problem ; but in the second World War both oven capacity and coking -coal mining capacity were pushed to the utmost . Because of inadequate supply , it became necessary to allocate a part of the production of these coals from other fuel use to coke production . This was done by the Solid Fuels Administration . These experiences raised a question , during and after the war, as to the nature and amount of the minable reserves of coking coal suitable for the manufacture of metallurgical coke ; and to what extent the lower -rank and lowergrade coals could be utilized by improving preparation and by appropriately blonding different coals . Obviously , much investigation and research are required to find answers to these questions . Somo work was done by Governmental and industrial agencies during the war , and , fortunately , more has been undertaken since the close of It is the purpose of this paper to review briefly our fuel reserves , with special reference to coking coal , and to discuss the problems of utiliz . ing progressively poorer coking coals as the reserves of high - quality coals approach depletion .

Mar 1, 1950

By A. G. Starliper

The report covers studies by the Bureau of Mines on the removal of metallic values in two waste products from the Longhorn tin smelter at Texas City, Tex. One product was a slag that contained tin, tungsten, iron, tantalum, and columbium. The other product was a spent acid solution that contained tin, tungsten, iron, lead, copper, zinc, and silver and that came from presmelting treatment of impure tin concentrates. Molten slag was treated with sulfur or sulfur compounds and with coke, calcium carbide, or gaseous reductants to form tin sulfide that volatilized from the charge and to reduce tungsten along with iron and silicon to form a carbon-bearing metallic layer. The metallic layer was treated by an oxidizing alkali roast and then was water-leached to extract the tungsten. The waste acid was used in other experiments to dissolve an iron-tin- tungsten alloy (hardhead) obtained by direct reduction of the slag. An insoluble fraction containing tungsten, silver, silicon, columbium, and tantalum was removed, and copper was cemented on metallic iron, Tin was recovered by cementation on zinc plates, and lead was precipitated by adding sulfate ion. Iron was precipitated by increasing the pH which left a solution containing principally zinc. Slabs of hardhead were electrolyzed in an electrolyte consisting of waste acid to plate out groups of metals at different pH?s. The time did not permit thorough exploration of this method of treatment.

Jan 1, 1962