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By A. C. Johnson

This report is one of a series being prepared by the Bureau of Mines on exploration, development, mining methods, and costs at various mines in the United States. It describes operations at the Black Rock mine, Wah Chang Mining Corp., Mono County, Calif. The purpose of these reports is to promote development and conservation of our mineral resources by disseminating technologic information on mining methods, practices, and costs. The Black Rock tungsten mine of the Wah Chang Mining Corp. is 33 miles north of Bishop, Calif., in the Benton Range, Mono County, Calif. The property was acquired in August 1950 and a well-planned program of exploration, development, and exploitation resulted in a good production record with low costs. Operations were halted in July 1957, about 6 months after suspension of the tungsten purchase program by the Federal Government.

Jan 1, 1960

By Oliver Bowles

From the most remote periods of civilization, stone Las been used to perpetuate the memory of individuals or to immortalize their noble achievements. Ancient memorials ranged from simple piles of stone (cairns) or single markers to great obelisks and pyramid or magnificent mausoleums. The Taj Mahal at Agra, India, built of white marble by Shah Jehan in memory of the Empress Mumtaz Mahal, is one of the most beautiful and costly memorials ever built. It was erected between 1632 and 1050 at a cost estimated at a: high as $50,000,000, and it is today an object of unusual attraction for travelers. Other magnificent memorials, both ancient and modern, are to be found in many lands. Memorials of varying design have characterized the passing centuries and have found an important place in the New World. In early days, monuments were chiefly imported into America, but gradually an extensive memorial stone-manufacturing industry developed on this side of the Atlantic. Sales value of domestic memorials, f.o.b. quarry or mill, attained a maximum of $17,488,755 in 1920, and retail sales, of course, reached a much higher figure. Modest markers and tombstones are to be found in almost every rural community in the United States, and there are many elaborate and costly monuments in and near urban centers.

Jan 1, 1938

By George D. Drechsler

The purpose of this review is to provide an analysis of the supply and demand for coal in Europe in 1955-56 and estimates of future growth in European requirements as a medium for appraisal of the effects and benefits to the economy of the United States. This review stems from observations and evaluations made in contacts with Government and industry representatives of the principal countries of Europe and is based on detailed data selected from the established flow of unclassified economic and statistical material originating in overseas areas for use and deposit in the Bureau of Mines, Foreign Solid Fuels Section. This material includes current reports and analyses prepared by the United States Foreign Service, official reports of individual countries, foreign industry and trade publications, and the committees of the several European organizations engaged in continuing review and study of problems relating to fuels and energy. The review is presented in four sections: 1. Discussion of the more important factors relating to the present and future fuels and energy position of Western Europe.

Jan 1, 1957

By John A. Johnson

[Tests were conducted at the Mount Weather testing adit of the Bureau of Mines4/ on the effectiveness of spraying water along the outside of the drill steel as compared with standard wet-drilling practice. The spray equipment used in the tests was designed primarily for the control, in quarries, of dust from dry drilling with solid type drill steel. EQUIPMENT Spray equipment is made in sizes to fit different drill steel but is alike in design, the only difference being in the diameter of the ring and the number of spray holes. The device is made of cast steel and has a coating of Stellite on the inside edge that comes in contact with the drill steel. It looks like a garden spray, except that the spray holes point in only one direction.]

Jan 1, 1939

By A. B. Hooker

A list of permissible mine equipment, tested and approved by the Bureau r. Mines previous to January l, i-)4, , was published in Bureau c Moines In ornation Circular 7207.3/ The l ,.t c -. that dote was complete as to equipmentthen available and in current Information Circular 7210,?+/ published as a supplement thereto, listed equipment approved during; the calendar 1942. Information Circular72x'3,_/ published as a second supplement thereto, ! listed equipment approved during the calendar year 1943. The present listis. Another supplement covering approvals issued during the calendar year 1c)44. The items are numbered crud to indicate the consecutive order in which each typo of machine or device was approved _.c?. in its particular classification. Thus Information Circular 7207 gave 1,t drills and drilling much fines on the Bureau'sactive.. d active list Ih: additional anal approval: were given in 1942 the three issued in 19 and one issued :n 1944- bring the total to `3. Item 111, under. Loading Machines and conveying appeared in lnformation Circular 7207. It is repeated ',tore to _how that on j,,l was granted Curia 1the optional of this loader when modified .'or 2 0. alt ciruits .]

Jan 1, 1945

By M. A. Lucas

The Bureau of Mines has developed a computerized mathematical model to predict the distribution of accessory elements throughout a metallurgical process. The model can be used to determine process conditions that effect better accessory element control consistent with continued high primary metal recovery. The model presented is specific for determining the bismuth distribution in lead smelting but can be adapted to most extractive metallurgical processes. Thermodynamic, kinetic, and process parameters form the base for the model. Its logic and structure are described in detail.

Jan 1, 1983

By John A. Johnson

Tests ere conducted at the Mount Weather testing adit of the 57 Bureau of Mines on the effectiveness of spraying water along the outside of the drill steel as compared with standard wet-drilling practice. The spray equipment used in the tests was designed primarily for the control, in quarries, of dust from dry drilling with solid type drill steel. Equipment Spray equipment is made in sizes to fit different drill steel but is alike in design, the only difference being in the diameter of the ring and the number of spray holes. The device is mace of cast steel and has a coating of Stellite on the inside edge that comes in contact with the drill steel. It looks like a garden spray, except that the spray holes point in only one direction.

Jan 1, 1939

By John Ward Smith

Methods for estimating the amounts of nahcolite, dawsonite, and the sum of these two sodium carbonate minerals from oil-yield assay data are developed and evaluated for Green River Formation oil shales from the saline section of Colorado's Piceance Creek Basin. Derived statistically, these estimation methods depend on the fact that these minerals yield water and gas measured during oil-yield assay. The estimation procedures yield values for nahcolite and nahcolite-plus-dawsonite of sufficient accuracy for stratigraphic plotting and correlation, whereas estimates for dawsonite are more generalized. However, resource estimates and reserve computations for both nahcolite and dawsonite accurate within 10 percent of the real value are readily available by summing the mineral amounts calculated by the procedures presented. These estimation procedures are applicable to oil-yield assay data on core samples from more than 30 coreholes which have penetrated the saline section of the Green River Formation in Colorado.

Jan 1, 1972

By R. W. Stahl

One of the broad purposes of the Bureau of' Mines since its establishment has been conservation of mineral resources. As some of the coal beds approach depletion, especially those coals suitable for making metallurgical coke, more and more attention is being given to means of recovering a larger percentage of coal in place. The customary system of mining in the United States is by room and pillar, or some variation thereof, which leaves pillars of coal to support, the roof. In many operations, where the pillars are not systematically recovered, the loss of coal often amounts to 50 percent or more of the original deposit. In many instances in developing new mines, It is planned to recover chain and barrier pillars on retreat when the mine has reached established boundaries. Too often, however, mines are abandoned for some unforeseen reason before completion of mining without recovering any pillars. Usually, these pillars are lost forever. With this in mind, the Mining Division, Region VIII, of the Bureau; of Mines is encouraging mining by longwall methods. It is a generally known fact that almost all of the European coal is mined by longwall methods, which are conducive to a high percentage recovery of coal. A comparison between mining systems usually is on the basis of tons per man per shift. Unless all operating conditions are similar, such a comparison could be misleading. Generally, the output per man shift in European longwall mines is less than that obtained in room-and-pillar mining in the United States. In European mining, maximum recovery of coal is not only mandatory but it must be accomplished without major damage to surface by subsidence. These restrictions necessitate packing or stowing with consequential increases In manpower and decreases in output per man shift.

Jan 1, 1954

By Robert Howard

With the rapid depletion of the Peerless Coal Co.'s mine in Spring Canyon, it was necessary, if the company was to remain in the coal-producing business, to look to the development of a new property or to acquire a mine already developed. After careful investigation of several operating properties it was decided by the officials of the company to take over the lease on an undeveloped acreage held by a private party in Price Canyon, about 3 miles north of Castle Gate, Utah.

Jan 1, 1930

By M. L. Whisman

Radiotracer techniques were developed for stoichiometric studies of photochemical reactions associated with atmospheric smog formation. Stock blends of separate hydrocarbon and oxygenated compounds were prepared and calibrated. 14C-labeled reactants and products in reaction systems involving hydrocarbons and nitrogen oxides at the ppm level were analyzed for qualitative and quantitative data. Precision and accuracy of these methods developed by the Bureau were determined by replication and statistical treatment of data, and these methods are described.

Jan 1, 1969

By G. A. Apell

The presence of considerable mineralization at the surface together with other favorable conditions suggested inclusion of the Nigger Jim diggings area in a comprehensive study of shallow lead deposits in southwestern Wisconsin. The area, which was the site of considerable shallow development some 60 to 70 years ago, offered the possibility of substantial quantities of lead at near-surface horizons. The investigation included completion of 30 churn-drill holes totaling 1,808 feet of drilling, 2 diamond-drill holes totaling 164.5 feet of drilling, and 25 feet of test pitting in two excavations. The degree of mineralization was determined in an area l,500 feet long and 150 to 300 feet wide along a mineralized trend that has not been investigated beyond the limits of the zone drilled by the Bureau of Mines.

Jan 1, 1948

A complete list of permissible mining equipment, rescue apparatus and gas masks tested. Prior to Jan. 1, 1929, w s published in Bureau of mines Information Circular 60972. The present list includes practically all equipment tested and. approved by the Bureau, up to and including July 1, 1929. It covers electric air compressors, coal drills, mining machines, loading machines, conveyors, mine pumps, room hoists,, mine telephones, rock-dusting machines, switches, electric cap lamps, flame safety lamps, electric hand and trip lamps, flash lamps, methane indicators and detectors, blasting units, storage battery locomotives, tandem locomotives, power trucks, concrete mixers, self-contained oxygen breathing apparatus and gas masks. The system under which these devices were tested permits the manufacturer, after his equipment has passed certain tests prescribed by the Bureau of Mines, to mark his equipment with a seal showing hat it has been "approved" by the Bureau. These tests are designs to insure that the equipment has the minimum requirements for safety in use. The only object of the Bureau in making such tests and publishing lists of permissible equipment is to safeguard the lives of workers and to help lessen the hazards of mining.

Jan 1, 1929

By A. B. Coates, J. E. Crawshaw

"The use of such methods and apparatus as the Dautriche method and the Mettegang recorder for the determination of the rate of burning of black blasting powder and other strictly burning explosives has been found to give such erratic results that no reliance can be placed on the data thus obtained. Consequently, investigators of those factors which may affect the burning rate, such as size of grain, absolute density, chemical composition, and means of ignition have had to rely mainly on observations made during practical use for determination of the part played by each. Such tests are very difficult of interpretation.The purpose of this paper is to describe a method used by the explosives division of the Bureau of Mines for the investigation of such explosives and to present the results of an investigation using that method.The investigation was concerned with the effect of grain size, initial pressure, and means of ignition on the rate of burning or rate of pressure development of black blasting powder as compared with pellet powder.The Bichel pressure gauge was used for these tests, with the slight modification to the apparatus and method described in U. S. Bureau of Mines Bulletin 15.4 These modifications consisted of reducing the speed of the revolving drum on which the time-pressure record is taken, measuring the speed of the drum by a belt-driven tachometer, and introducing an induction coil in series with the electric squib or electric detonator to mark on the time pressure record the instant at which the squib or detonator was fired."

May 1, 1929

By Jack R. Woodyard

Bonding angles, promotion energies, and relative atomic sizes can be estimated through the solution of a set of algebraic equations generated from simple atomic models, and quantum mechanical parameters such as bond strength can be estimated from simple, hydrogenic form-wave functions. The precepts of The Engel-Brewer Theory are melded with the "Crystal Approximation Model" to produce atomic-structure models making these predictions, The two-valence-electron case is presented in this report. For the candidate atoms Be, Mg, Ca, Sr, and Ba the calculated promotion energies agreed within a few percent of their experimental values. These atomic parameters determine the possible crystal structure of the candidate atoms when alloyed. This is part of the effort at the U.S. Bureau of Mines to develop methods for alloy design in response to requirements for new high-performance alloys that conserve critical or rare materials.

Jan 1, 2010

By Arnold O. Tanner

The domestic mining industry continued to be strengthened and revitalized in 1989. The healthy conditions and the industry comeback that began in 1987 continued to spread and became more established for many commodities. Relatively comfortable and stable commodity prices, still found predominantly in the metals sector, reinforced other operational factors in bringing vitality to the mining and mineral processing industries. New streamlined business practices, mine and plant modernizations, and the progressive use of new technologies successfully helped lower operating costs and increase efficiency during the past 5 to 7 years. An element common to these three factors of industry renewal and growth was the ever-increasing infusion of and growing dependence on constantly advancing computer technology applications. This trend of increasing computerization was occurring throughout the mining and mineral processing business while it similarly was in most facets of modern business and culture. Some commodities and companies still struggled to outlive sluggish prices and other unstable market conditions or to modernize their businesses, but increases in productivity and profits were more common. A trend toward increased mechanical excavation in nonsoil materials was beginning to surface as a substitute for standard cyclic mine development techniques, such as drill-and-blast and surface shovel-and-truck routines. More continuous mechanical excavation offered the potential for increased production, fewer people at the working face, better ground control, and generally improved safety. The main limitation was rock hardness. The construction industry had already recognized the benefits of tunnel-boring machines for long underground drives and mechanical planers for pavement removal. The Colorado School of Mines held a short course during the year entitled, "Mechanical Excavation Techniques in Mine Development and Production,'" which was at-tended by nearly 100 engineers from 12 countries. The consensus of attendees was that for the most efficient use of these machines and techniques, new mining plans needed to be developed beyond the simple adaptation of those excavators to existing mine plans.1

Jan 1, 1991

By Chas. F. Jackson

This paper is a tabular compilation of data contained in a series of information circulars dealing with mining methods and costs at a large number of mines in the United States and some foreign countries. There circulars have been published from time to time during the years 1929 to 1934 inclusive. From time to time, as enough data became available in these circulars, other circulars and. bulletins have been published in which the data bearing upon different phases of nine operation were summarized, discussed, and analyzed. The present paper is a compilation of data on costs of drifting and crosscutting contained in earlier circulars, .designed to assemble this information in a convenient form for reference without attempting lengthy discussion of details of drifting and crosscutting practice. For such details the reader is referred to the circulars on individual mines.

Jan 1, 1935

By R. B. Schluter

The objective of this Bureau of Mines investigation was to determine the effects of adding manganese compounds and ores to iron ore pellets. Manganese dioxide, carbonate, sulfate and chloride, plus six manganiferous ores from the Minnesota Cuyuna Range were tested as additives to increase the manganese content of iron ore pellets. One to 5 percent manganese, as a compound or ore, was added to five magnetite concentrates and one hematite concentrate. These concentrates were ballad, indurated (1,300° C), and tested for reducibility. Manganese sulfate and chloride were unsatisfactory additives causing cracking and degradation of the pellets during reduction. Manganese dioxide, carbonate, and the ores were satisfactory additives. The additives increased pellet compression strengths with a corresponding loss of reducibility, as compared to the pellets without manganese additions. The changes in compression strengths and reducibility were caused by the formation of Jacobite spinel and slag within the pellets. However, when the induration temperature was lowered from 1,300° to 1,200° C the reducibility and compression strengths were comparable to the pellets without manganese additions indurated at 1,300° C.

Jan 1, 1974

By J. J. Forbes

The Coal Mine Inspection Branch of the Health and Safety Division, Bureau of Mines, was established to carry out the provisions in Public Law 49, 77th Congress, H. R. 2082, approved May 7, 1941. The series of major disasters that beset the coal-mining industry in 1940 aroused public interest in mine-safety measures, and the act 18 the direct result of this rekindled interest. Under the provisions of the act, the Secretary of the Interior, acting through the Federal Bureau of Mines, is authorized and empowered to make, or cause to be made, annual or necessary inspections and investigations in coal mines, the products of which regularly enter commerce or the operations of which substantially affect commerce. The principal functions of the Federal coal-mine inspectors are to determine the causes of accidents and occupational diseases in coal mines and then endeavor to eliminate or ameliorate them (1) by revealing, through personal conferences with mine personnel, correspondence, and published reports, the unhealthful and unsafe conditions and practices existing in the mines and (2) by recommending practical means for correcting the conditions observed. The act does not provide any enforcement powers, and therefore compliance with the inspectors' recommendations is not mandatory; it does give Federal coal-mine inspectors the right to enter coal mines for inspection purposes.

Jan 1, 1951

By D. S. Kingery

This study describes five fatal accidents so unusual in occurrence that the chain of circumstances bringing them about may never be duplicated. The intent of this publication is to illustrate that everyone working underground is subjected, at all times, to definite inherent mining hazards and that safety devices, though provided, often are ineffective or not used. It is hoped that a study of these fatal accidents in bituminous-coal mines will show workers and safety engineers that nothing can be taken for granted. Safety planning with continuous study can prevent these unusual accidents as well as the routine recurring types, which cause the majority of coal-mining injuries. The treacherous, fatalistic philosophy that "it can't happen to me" or that "when my time's up I'll get it regardless of what I do," still prevails among individuals and even safety engineers. The individual or safety man who believes in luck as applied to safety should not read any further, since this study was written for the sincere, safety-minded individual who accepts the prevention of all accidents as a challenge to his knowledge, initiative, persuasiveness, and salesmanship.

Jan 1, 1954