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By W. H. Eddy

The Bureau of Mines used several laboratory batch flotation schemes combined with magnetic separation to investigate the feasibility of recovering potash feldspar and glass sands from molybdenite tailings. Four molybdenite tailings or prospective tailings were used as test samples. Feldspar concentrates containing from 10.7 pct to 12.0 pct K2O were recovered from three of the four samples. The alkali content of the fourth sample met the grade for a mixed feldspar. All the feldspar concentrates contained iron in excess of the 0.10-pct-Fe203 specification for most uses. Electron-beam microprobe examination of the feldspar concentrates showed the presence of an iron-bearing potash feldspar in quantities that were excessive with respect to most iron specifications. However, a high-quality glass sand was produced from all of the samples.

Jan 1, 1980

By G. R. FITT, S. R. B. Cooke, C. W. Davis, V. H. Gottschalk, C. G. Maier, C. E. Wood, R. S. Dean, S. B. THOMAS, John Gross, E. P. Barrett, T. L. Joseph

Lack of funds has prevented publication of much of the metallurgical work of the Bureau of Mines during the past 2 years . The present progress report covers studies in the direct production of iron and steel . The experimental work was carried out in cooperation with the universities of California , Minnesota , and Missouri . Complete reports will be published when funds are available .

May 1, 1934

By Richard W. Watson

Card-gap and projectile impact sensitivity data are presented for a wide variety of explosive compositions tested at the Bureau of Mines in more or less standard test geometries. The results of both tests are in good agreement in that they provide the same sensitivity ordering for different subclasses of explosives. Least sensitive were homogeneous liquids that did not exhibit a tendency to undergo low-velocity detonation, ammonium nitrate-fuel oil, and most cast military explosives. Of intermediate sensitivity were pressed and powdered military explosives, cast pentolite, permissible and non- permissible water-based explosives, and one commercial two-component explosive. The most sensitive were permissible and nonpermissible dynamites and explosives susceptible to low-velocity detonation.

Jan 1, 1973

By Th. G. Sahama

This paper contains some new heat-of-solution measurements of geikielite (MgTiO3), limonite (FeTiO3), fayalite (Fe2SiO4), and a natural forsterite in mixed acid (HF +HCl) and gives the results of a thermodynamic attack on the problem of stability of geikielite in rocks.

Jan 1, 1949

By R. S. Dean, John Gross

"In a preliminary report made a year ago it was shown that certain minerals when subjected to heating with water under high pressure and temperature were shattered upon the sudden release of that pressure. The main feature in which the results of this method differ from those of conventional grinding is in the differential effect obtained. The more metallic minerals, and hence the valuable minerals, are shattered more readily than are the gangue minerals. In other words, explosive shattering is unique among possible methods for comminuting an ore in that it wastes the least energy on the useless part of the ore. Explosive shattering, therefore, offers possibilities as a means for reducing grinding costs, arid it is this potential advantage of the process that makes it worthy of further experimental study. The first part of this paper is devoted to a study of the mechanism of the process; the, second part reports results obtained in toots on a selected list of ores to exhibit some of the advantages of explosive shattering."

Feb 1, 1933

By S. M. Shelton

The widespread occurrence of domestic manganese deposits and the shortage of ferromanganese-grade ore have been sources of much speculation and investigative effort for many years. The present emergency has intensified the search by the Bureau of Mines for methods of producing ferromanganese-grade concentrates4/ from low-grade ores.

Jan 1, 1941

By S. M. Shelton

[The widespread occurrence of domestic manganese deposits and the shortage of ferromanganese-grade ore have been sources of much speculation and investigative effort for many years. The present emergency has intensified the search by the Bureau of Mines for methods of producing ferromanganese-grade concentrates4/ from low-grade ores.]

Jan 1, 1941

By J. W. Thompson

This work is a codification and annotation of the Congressional enactments relating to minerals, mineral lands, and mining. It covers every enactment of Congress from the original ordinance of 1785 to the present time, as well as all sections of the Revised Statutes of the United States relating to these subjects. These laws are grouped according to their general subject matter, and are arranged thereunder in numerical or chronological order. Many of the mining statutes include matter not pertinent to the subject, and only those parts of such acts are quoted as will properly show their relation to minerals and mineral lands and indicate how they should be construed. Some mining acts have been repealed or have become obsolete, and others have become incorporated substantially in sections of the Re- vised Statutes; but these are retained in order to show the changes made, and the constructions placed thereon by the courts are given as aids in construing the new or repealing acts. The annotations consist of legal propositions abstracted from the decisions of the various courts and executive officers of the Govern- ment that have interpreted the sections and statutes so codified. These legal propositions are arranged under the different sections and acts with appropriate headings, titles, and subtitles, in logical order, exhibiting the present status of each particular section or act and its application to the subject of mines and mineral lands. The annotations do not purport to be abstracts of decisions on the sub- stantive law of mines and mining generally, but are limited strictly to the interpretation placed on a given section or act definitely re- ferred to by a court or executive officer by the number of the section of the Revised Statutes or the volume and page of the Statutes at Large in which the Congressional enactment is found. It may be observed that the legal propositions stated are not always pertinent to the particular section or act under which they are classed and of which they purport to give a construction. The arrangement, however, is not an arbitrary one, but is so made for the reason that the courts or officers in the construction of a particular section or act definitely referred to by number or volume and page incorporated in the decision matter not strictly pertinent to the par- ticular section or act so designated. This statement applies especially to the interpretations placed on the sections of the Revised Statutes. The decisions abstracted for the purpose of this work are those of the United States Supreme Court, 234 volumes; the various Federal courts, 214 volumes; the decisions of the Department of the Interior

Jan 1, 1915

By Richard F. Hewlett

An attempt has been made to fit assay data from an underground copper deposit to a three-dimensional polynomial surface as a means of expressing assay points in terms of their mine coordinates by a mathematical equation. The resulting equation was evaluated to predict the grade trend of the deposit. Although the fit obtained by this initial experiment is not considered accurate enough to provide good predictions about the deposit, the methodology is presented in this preliminary report to show the potential usefulness of the technique in mineral deposit evaluation. The technique also should be useful in determining the grade of blocks of ore for production scheduling and blending problems in open pit operations. Further experimentation is needed to increase the reliability of the computer program, to increase the precision of the method, and to make the solution more flexible for use on other mineral deposits.

Jan 1, 1964

By R. J. Leary, W. M. Mahan, F. X. Tartaron

A new type of apparatus for prerefining molten blast furnace iron and to reduce the cost of subsequent steelmaking consists of a funnel - shaped device lined with firebrick into which a horizontal stream of molten pig iron is directed tangentially at the top . The rotary motion thus induced causes the stream to flatten itself upon the wall and flow in a spiral path to the outlet ; thus , the device was termed " vortex cone .' Oxygen and other refining agents are impinged upon the flowing metal in the cone where reaction is facilitated by the large metal surface exposed and the turbulent flow pattern . Experiments with water in 1 - foot - diameter funnels provided an idealization of the flow patterns to be expected with molten iron . A brick - lined reactor 3 feet in diameter was built for desiliconizing molten pig iron in lots of 1 to 2 tons . At flow rates of 0.3 to 0.5 ton min - 1 (430 to 720 tons per day ) this apparatus was 64- to 90 - pct effective in desiliconization with oxygen efficiencies of 19 to 41 pct . Detailed experiments to develop basic engineering data are underway , and adaptation of this principle to other reactions and reactants is planned .

Jan 1, 1964

By Milton Orchin

There has been a good deal of speculation as to the function of a vehicle in the coal hydrogenation process. One of the most fruitful theories has been the suggestion that a vehicle such as tetralin functions by supplying hydrogen to the coal, and that the high-pressure hydrogen present in the system serves to regenerate the tetralin. In order to obtain experimental evidence bearing on this theory, a series of experiments was planned in which varying quantities of tetralin were used with coal in the presence of high-pressure hydrogen. This paper reports the results of these experiments.

Jan 1, 1949

By Walter Wood, J. T. H. Cannarella, H. F. Yancey, R. E. Zane

More than 50,000,000 tons of bituminous coal and probably about the same quantity of anthracite are cleaned annually in the United States by wet methods. The water, fine coal, and impurities from the water used for washing ordinarily are recovered by moans of various forms of settling tanks. Settling and clarification may be hastened markedly, thereby greatly increasing the capacity of clarification equipment already installed, by the addition of substances to the washery water that cause the fine particles in suspension to agglomerate and thus settle more rapidly. This phenomenon, although well known and applied in other fields, has been used at only a few coal washeries in the United States. It is widely employed, however, as an aid in the recovery or disposal of fine coal or impurities, as a means of preventing, stream pollution, and to enable reuse of washery water at many plants in Europe. Pioneering work in the United States has been done principally by two companies -- the Pittsburgh Coal Co., in Pennsylvania, 6/ and the Pacific Coast Coal Co., in Washington.

Feb 1, 1940

By Spangler Ricker, F. T. Johnson

"SUMMARYThe Ione-Carbondale clays area is 2 miles northwesterly of Ione, Amador County, Calif. It was explored during the war by the Bureau of Mines to obtain data on the alumina content and to recover representative samples for beneficiation tests for alumina recovery.Seventy holes, aggregating 8,837 feet, were drilled, and about 10.3 acres of land was cleared of underbrush. Maps and cross sections were compiled showing location of holes, analyses, and other pertinent data.The clay beds vary in thickness from 13 to 196 feet, and are covered by a loose overburden, averaging about 11.9 feet in thickness. The ratio of overburden to clay is 1 : 8.2. Analysis of a composite sample showed the recoverable alumina (A12O3) and Fe2O3 content to be in the order of 23.6 percent and 2.8 percent, respectively.Topography of the clay area is ideal for open-pit mining methods and plant site.INTRODUCTIONInvestigation of alumina-rich clays for the possible production of aluminum was made during the recent war period, when the shortage of bauxite was becoming critical.Results of field examinations by the Bureau of Mines and the Federal Geological Survey indicated that one of the most promising areas for the development of alumina-rich clays is in the Ione-Carbondale district."

Mar 1, 1948

By D. Harrington

The Bureau of Mines was created in 1910 largely to determine methods of preventing coal-mine explosions; the Bureau's studies have proved that coal dust, except possibly that of some grates of anthracite, can initiate an explosion in the absence of gas and that its ability to extend or propagate an explosion of either gas or dust has been responsible for nearly all of the widespread explosions that have taken place in bituminous and other nonanthracite mines in the United States in the present century. It is believed by many persons that all atmospheric dusts may be harmful if breathed in large enough quantities for long enough time; bituminous coal dust is generally considered to be essentially harmless physiologically, yet there is abundant evidence of definite damage from inhalation of bituminous dust mixed or unmixed with the dust of other materials. Attention un¬questionably should be given to allaying dust in bituminous mines, especially at principal dust-producing sources. This publication enumerates some of the sources of dust and describes practical methods of employing water as one of the most effective of the known methods to allay dust in bituminous mines.

Jan 1, 1938

By C. W. JEFFERS

At its annual meeting on March 5, 1928, in Washington, D. C., the Joseph A. Holmes Safety Association gave to the Ford Collieries Co., Curtisville, Pa., a certificate of honor for "having worked 922,628 underground man-shifts from August 14, 1920, to December 31, 1926, producing 5,755,669 short tons of coal without a fatality." This remarkable record certainly deserved recognition. It developed that this company's freedom from fatalities continued until October 2, 1929, hence the full period during which no underground fatalities occurred was from August 14, 1920, to October 2, 1929, or 9 years, 1 month, and 18 days, the total tonnage being over 7,700,000. Table 1, shows the complete safety record of the Ford Collieries Co. since 1920 as given by the officials of the company. The first item in Table 1 shows a remarkable performance. This company since 1920 has mined 15 times more coal per fatal accident than the average pro- duction per fatal accident for the State of Pennsylvania in 1928 (255,257 tons). Excluding the two fatalities (one in 1922 and one in 1929) the severity rate for the same period has been 1.259 per thousand hours worked, a record of which the company may justly be proud. However, including the fatal accidents the rate is 2.407. This compares favorably with an average of 12.4 in 1928 for 66 mines in the National Safety Competition. The Ford Collieries Co. operates three mines located in the vicinity of Curtisville, Allegheny County, Pa. One of these mines, Benjamin No. 1, is idle at the present time. The officials are: A. R. Pollock, general manager, Curtisville, Pa., and C. W. Pollock, assistant general manager in charge of safety and operation.

Sep 1, 1930

By P. L. Woolf

Three trials with oxygen-enriched unheated blast air are described. The trials were conducted in the Bureau of Mines experimental blast furnace located in Bruceton, PA. The first trial utilized moisture addition to the oxygenated blast. The second and third trial were conducted with natural gas injection. The test was basically a feasibility study and in that regard the practice was demonstrated to be feasible and also have possible advantages over hot blast operation. The testwork was conducted in 1964 and 1965 as part of a continuing study of iron making technology in cooperation with several North American Steel Companies.

Jan 1, 1985

Operator efficiency and control capability along with cost effectiveness have been the quest of mining, industrial, and mobile hydraulic engineers for years. The majority of the functions in present day fluid power systems are controlled by on/off control valves. They are inexpensive and provide easy installation and operation, but they lack the quality of fine control of load flow or what is sometimes known as "feathering the load". An alternate approach to obtaining this capability is the use of electro-hydraulic servo-valves, but their implementation into a system is complex, and they are expensive. As a result, electrohydraulic systems are still used primarily in the aerospace industry. Of late, a compromise seems to have evolved between the on/ off control systems and the servo-technology is the so-called proportional flow control valves. A proportional flow control valve meters fluid to the load in proportion to the input command from the operator. In principle, it is similar to a conventional flow control valve and is tailored to meet the control requirements from the load point of view. The hydraulic system using this valve usually works in an open-loop mode with the operator closing the loop. Incorporating load-sensing mechanisms and adoption of electrical/electronic signalling into the valve make it the "ideal valve" which designers have been looking for from a techno-economic point of view.

Jan 1, 1983

By George A. Burrell, Frank M. Seibert

The Bureau of Mines, as part of its designated duty of investigating the causes of mine accidents, is conducting at its experiment station in Pittsburgh, Pa., a study of mine gases. Some of the work already done in connection with this study is outlined below. A large number of mine-gas samples have been collected under normal conditions in returns and in splits, and at other points in the ventilating current, also at the face, in the goave or gob, in unventilated places, and wherever the air was still. Samples have also been obtained under abnormal conditions, as after explosions and while mine fires were in progress, or from sealed areas behind stoppings and darns where the air had been stagnant for some time. Chemical changes in the composition of mine atmospheres during mine fires have been studied," and conditions peculiar to certain mines have been investigated. The question of the effect of a change in atmospheric pressure on the escape of gas (methane) in coal mines has been studied. Explosives have been fired in both coal and metal mines, and samples of resulting gases have been collected to ascertain the degree to which these gases vitiate the air. A series of samples in mines where gasoline locomotives were being used have been examined in order to ascertain the degree to which the exhaust gases from such locomotives foul the mine air. Experiments have also been performed in regard to the relative effect of carbon monoxide b upon men and small animals. A preliminary report relating to the inflammable gases in mine air has been published. Full reports of the results of the investigations outlined above will be published as soon as all the necessary data have been gathered. The first part of this report deals with the methods used by the bureau in the collection and examination of the various mine gases; the latter part discusses the bureau's methods of sampling and examining natural gas.

Jan 1, 1913

By James C. Barker

Yttrium and rare-earth element. pegmatite dikes are associated with a peralkaline granitic and nephelene syenite complex near Dora Bay on southern Prince of Wales Island. Mineralized dikes were mapped and sampled during USBM investigations in 1987 and 1988. Coarse-grained pegmatite dikes, which emanated as late-stage magmatic fluids from the intrusion, further evolved into vein-dikes and ultimately silica-rich veins. The dikes can be traced up to two miles along a north-south zone. Lithophile elements exhibit a pronounced zonation in vein-dikes and veins that are distal to the Dora Bay complex with increasing values correlating with increasing distance from the complex. The pattern of mineralization suggests very late stage magmatic fluids containing the incompatable lithophile elements were injected into a preexisting north-south fracture zone. REE mineralogy exhibit fine-grained intergrowths of principally thalenite and bastnaesite with lessor monazite and eudialyte. Euxenite contains most of the columbium values and zircon is commonly associated with the dikes. Estimates of inferred and hypothetical resource tonnage range from 1.7 X 1C6 to 8.5 X 106 st for two deposits. Contained RED (including yttrium) averages 0.5 pct and ranges up to 2.0 pct. Deposits are of polymineralic composition and about half of this resource comprises the heavy yttrium subgroup.

Jan 1, 2011

By Joseph A. DeCarlo

This publication presents statistical data on oven-and beehive-coke plants in the United States. Information on the carbonizing capacity of the coke industry is important because of the close relationship between the coke industry and most of the other basic industries of our country. Coke is an essential-raw material in pig-iron production; also, coal-chemical materials are used to make fertilizers, paints, plastics, synthetic rubber, explosives, detergents, nylon, pharmaceuticals, dyes, and many other useful products necessary to sustain and improve the high standards of living in our country. Oven-coke plants in the United States on December 31, 1958, are tabulated in table 1. This tabular presentation shows the location, classification, number and type of ovens, annual coke capacity, coal chemicals produced, and name and address of parent company for each individual coke plant. About 86 percent of the capacity of slot-type coke ovens in the United States is owned by iron and steel companies. In most of these plants the coke ovens are integrated with the blast furnaces to facilitate transportation of raw materials for steel making. This has resulted in large coke plants, and the average annual coke capacity of "furnace" plants in 1958 was 1.3 million tons. Nonfurnace or "merchant" plants include coke plants associated with chemical operations, gas utilities, as well as coke plants that produce metallurgical, industrial) and residential-heating grades of coke and coal-chemical materials for sale on the open market. These plants ordinarily are not as large as furnace plant~ and annual coke capacity of merchant plants in 1958 averaged only 500 thousand tons. At the end of 1958 there were 55 furnace plants and 22 merchant plants.

Jan 1, 1959