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By G. S. Rice

To those concerned in attaining greater safety to life and incidentally to property in coal mining, the meeting of representatives of the national mine safety research organiza¬ tions of the principal coal-producing countries, which was called by the Safety in Mines Research Board of Great Britain at its experimental station near Buxton, should have deep significance. It is notable, first, because it meant the friendly cooperation of countries not many years ago engaged on either side in the great World War; and second, because of the remarkable degree of agreement in the essential fundamental factors and methods of attaining greater safety in coal mines when it is considered that the questions were approached by different paths and that the applications dealt with widely differing natural conditions and national points of view. Varying views, of course, were held as to the relative importance of certain factors, but the differences were of detail rather than of principle. When the meeting adjourned it was unanimously agreed that such meetings should be continued annually and that the greatest benefit was to be derived by close cooperation in the exchange of data. Belgium, France, Germany, Great Britain, and the United States were represented by one or several members of the respective national research organization. It is of interest to note that this research work in Belgium, France, and Germany is supported directly by na¬ tional organizations of mine operators or owners but placed under a scientist appointed by the respective Government, thus giving the work official standing. In Great Britain the work is carried on by a Government board, consisting of persons connected with the coal¬ mining industry or in mining research, appointed by the Secretary for Mines, to direct the work of research of the Mines Department. It does not, however, come under its inspection service. Its work is supported by a penny-a-ton tax on output of coal. In the United States the mine-safety research work is directly supported by the Federal Government.

Dec 1, 1932

By M. M. Hassan

This report describes the analysis tools developed at West Virginia University which can be implemented to optimally design coal mine electrical systems. The basic analytical tools for all power systems are the load-flow and short-circuit analysis. Well known programs have been developed for analysis of ac transmission and distribution systems, but they are not applicable to a system which has combined ac/dc distribution, such as a coal mine power system. Furthermore, the topology of a coal mine electrcal system changes continuously due to the movement of the locomotives on the track. In the first section of this report, algorithms for carrying out load flow and short-circuit analysis of a coal mine electrical system are described. Results from the study of a typical coal mine system are presented. In the second section a method is described to optimally size power cables for cyclic loads. The method is based on the development of a thermal-electric model for a low-voltage power cable. Results from experimental verification of the model are also presented. These techniques are useful in the safe, efficient, reliable and economical design of the coal mine electrical power systems.

Jan 1, 1979

By A. L. Engel

This report is a compilation of results of brief preliminary tests on sulfide ores that contained gold and silver and, in some cases base metals. It is a companion paper to a recent similar report on oxide ores. Simple treatment methods employing the least possible equipment sometimes produce satisfactory results on marginal ores and in small-scale operations. Investigations of typical ores from newly discovered or recently explored mining districts have been made in continuation of a long-established part of the hydrometallurgical and ore-dressing program of the Reno station, Bureau of Mines. The purpose of such investigations is to encourage the search for and development of mineral resources and particularly to assist in the economical exploitation of low-grade and marginal ores as well as the conservation and recovery .of values in products that were discarded from former operations because of inability to treat them profitably. Several of these investigations have been limited to preliminary tests of samples from prospecting operations, whereas same involved samples of old dumps or tailings piles. The test work in these cases was not extensive enough to warrant publication as individual reports, but is of considerable interest inasmuch as it indicates the possibilities as well as the limitations of treating the respective materials. The samples were representative of the districts from which they wore obtained, so this information should be helpful in the future development of these districts.

Jan 1, 1951

By W. L. Eaton

This report is the second in a series concerning the Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region; a catalog of the microfilmed maps of mines in the Wyoming Basin of the Northern anthracite field is presented. The first report I.C. 8274, published in 1965, was a catalog of microfilmed maps of mines in the Eastern Middle anthracite field. Additional catalogs will be published as the microfilming of significant mining areas is completed.

Jan 1, 1968

By J. A. Eisele

The Bureau of Mines conducted bench-scale cyclic tests to determine the composition of recycled leach liquor in the Bureau?s proposed clay/HCl leach/ HCl sparge process for producing Al203 from clay. The data developed from these tests make it possible to synthesize leach liquors for predetermined steady-state operating conditions when conducting large-scale crystallization tests. The results of two sparge tests were compared. One was a 20-cycle test with a 36-pct-HCl concentration in the mother liquor; the other was a 10-cycle test with a 26-pct-HCl concentration in the mother liquor. The effect of impurity concentrations in the leach liquor on the purity of aluminum chloride (AlCl30?6H20) crystals was determined, but there was poor correlation between this data and results that have been obtained from miniplant-scale work.

Jan 1, 1980

By W. W. Adams

[Sales of explosives - permissible explosives5/ other high explosives, and black blasting powder - in the United States during the calendar year 1937 reached a combined total that slightly exceeded the quantity sold in 1936. A larger output was reported for permissible and other high explosives but a smaller for black powder. Production of the three classes of explosives totaled 404,744,294 pounds, more than 3 percent over 1336. The total quantity produced included 49,579,441 pounds of permissible, 288,924,253 pounds of other high ex- plosives, 36,403,950 pounds of black powder in pellet form, and 23,836,550 pounds of black powder in granular form. Sales of granular black powder declined 26 percent compared with 1936 and of pellet black powder 12 percent; gales of permissible explosives increased nearly 4 percent and of other high explosives 10 percent]

Jan 1, 1938

By J. Mutmansky, C. Lee

"The size distribution of coal mine dust is one of its most important characteristics because the particle size is known to govern the region of deposition of dust within the human respiratory tract. In addition, dust characteristics, particle settling rate, transportability of the dust and the efficiency of dust control measures are all affected by the particle size. As a result, particle size distribution of the airborne dust in a coal mine is a fundamental property that impacts on the health of underground workers.This paper deals with some basic findings on the size distribution of cool mine dust based upon the results of data collection in six underground coal mines using continuous miners. All airborne dust sampling was performed on development sections using eight stage cascade impactors and permissible 2. O l / min pumps. Samplers locations were fixed in the sections with respect to the continuous miner and roofbolter or with respect to the intake and return airways • Sampling times varied from 45 minutes to 6 hours , depending upon the dust concentration. The first topic of analysis was the test to determine whether the commonly used lognonnal distribution is valid when applied to airborne coal mine dust. Secondly, the conventional method of representing the· distribution using two parameters, the geometric mean and the geometric standard deviation, is questioned. Since almost all size data were found to show some degree of bimodality, the two parameter lognonnal distribution may not represent the total airborne coal mine dust size , quite adequately. Bimodal lognonnal distribution was tested to be a good approximation in the case with two modes in the size distribution.The final topic discussed in this paper is the 'locational variation of the airborne dust size distributions within the continuous mining section. The size distributions varied considerably at the different sampling locations with the continuous miner and roofbolter producing the coarser distributions. Fine size modes in the range of 2 to 4µ m including mostly respirable dust particles were present in almost all samples • Second dust generating sources such as the shuttle car movement were found to be major causes of high respirable dust concentrations in some cases ."

Jan 1, 1988

Maps To Accompany Bulletin 418

Jan 1, 1941

By S. H. Lorain

"INTRODUCTION The veins of the Clark Fork district have been mined on a small scale since 1913. In May 1943, the district was examined by an engineer 3/ of the Bureau of Mines with a view to possible exploration for larger ore deposits that might be of value to the war effort. The area adjacent to the Hope, Whitedelf, and Lawrence mines was re-examined 4/ December 27, 1943. As a result, the Bureau of Mines started exploratory operations in the district during the summer of 1944 which was continued until the late spring of 1946. This report presents the data obtained from the investigation.ACKNOWLEDGEMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project' as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts the preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests."

Aug 1, 1946

By Donna D. Harbuck

The Bureau of Mines has investigated a process to produce titanium powder directly from titanium salts. If successful, such a process could lower the cost and increase the use of titanium. In this study, K2TiF6, K2TiF3, and TiF3 were reduced with potassium in the temperature range of 650° to 750° C. Under certain conditions, titanium powder 1.6 to 3.3 microns in size was produced. After leaching the product with a 0.1M HCl solution, powder impurities as low as 0.04 pct potassium and 0.28 pct fluorine were obtained. However, oxygen levels of over 1 pct and the frequent formation of insoluble byproducts demonstrate the need for further research to make the powder suitable for powder metallurgy applications.

Jan 1, 2011

By C. H. Schack, A. O. Ipsen, H. G. Poole

"INTRODUCTION In the course of the investigation of manganese mineral occurrences in continental United States, the Bureau of Mines has collected several lots of ore from properties in the vicinity of Long Valley, Ariz. The ore occurs as irregular and random pockets in a brecciated zone. As only high-grade portions of the deposits obtained by selective mining would be acceptable as commercial-grade manganese ores, an investigation was made to determine amenability of the ores to concentration by ore-dressing methods. Several types of ores, differing in grade and mineral associations, were studied.Ores from the Vaiazza property are of special interest, owing to the successful application of silica flotation for their concentration. Ores from the Shroup and Conner-Hough properties are very similar but differ somewhat in their response to ore-dressing Method's. In all instances, the man¬ganese minerals are psilomelane and pyrolusite, with minor amounts of other manganese oxides. The country rook is a brecciated limestone; the diluent in the high-grade ore pockets is chiefly silica. The low-grade manganese ores are limestone replacements, and the chief gangue material, of course, is limestone."

Nov 1, 1947

By James V. Kelly

During the winter of 1946 and the spring of 1947, the Bureau of Mines conducted an investigation and drilling program in the vicinity of the village of Fairplay, Wis. Fifteen diamond drill holes totaling 2,457.6 feet of bore were completed. This work was part of a general study of the zinc-producing area of southwestern Wisconsin and had the particular purpose of investigating a structural trend, determined by the Federal Geological Survey, in an area some distance from known ore bodies or active mines.

Jan 1, 1948

By Fred N. Kissell

A parachute-type stopping intended for changing the course of mine ventilation air during mine emergencies has been designed and tested. Some production uses are also visualized for metal mines. Preliminary tests in the laboratory and underground indicate that the parachute stopping is a workable concept, but further developmental research is required.

Jan 1, 1975

By Jr. East

The Bureau of Mines conducted an investigation of the Nightingale tungsten deposit about 38 miles north of Fernley, Nev., from September 1939 to March 1940, to determine possible resources of tungsten ore. The property was owned by the Gold, Silver & Tungsten, Inc., which maintained its offices in Boulder, Colo. Ore was discovered in 1917, and some ore was mined in 1918 and treated in a mill at Toulon, a station on the Southern Pacific Railroad, 40 miles east. Same shipments were made since 1918, but no production figures are available. The ore is mined from nearly vertical tactite bodies at the limestone-granite contact. The Bureau of Mines excavated 944 linear feet of trenches, drifted 52 linear feet, sunk a shaft 20 feet in depth, sampled the underground workings by cutting 743 linear feet of channels, sampled the surface trenches by cutting 415 linear feet of channels, and drilled 9 diamond-drill holes, totaling 3,000 feet. The ensuing sections note the location and physical features of the district and specify the property and ownership. The history of the mine is briefed, and the geology and mine workings are described. The work done by the Bureau of Mines is summarized and supplemented in detail by assay maps, logs of diamond-drill holes in appendix A, and a table of sample analyses in appendix B.

Jan 1, 1950

By Louis C. Brichta

"The O'Jack Mining Co.'s zinc and lead deposits in Jasper County, Missouri, have been worked intermittently since the early nineties; production from these deposits was greatest during World War I and II - 4,668 tons of zinc and lead concentrates. The deposits are in a sink-hole structure in which intense deformation has taken place and in areas of disturbance in the sheet-ground horizon.While high-grade ore was being mined, the operators sank seven churn-drill holes for the purpose of extending reserves. They then asked the Bureau of Mines to explore the deposit with the object of developing a reserve of lower-grade ore that could be mined by open-pit methods. Twenty-two holes were sunk. The methods of drilling and sampling and the logs of the holes, as of those drilled by the operators, are given later in this report.INTRODUCTION AND ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mined has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts development by each exploratory project as soon as practicable after its conclusion. Preliminary examination, conduct of exploratory work, and preparation of final reports are functions of the Mining Branch, Lowell B. Moon, chief, under the supervision of Dr. R. S. Dean, assistant director."

Nov 1, 1946

By Ott F. Heizer

This paper describing the mining practices at the mines of Massachusetts, Massachusetts Co., Inc., at Mill City, Nev., is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in tie various mining districts of the United States. The author acknowledges the assistance of William C. Vanderburg, associate mining engineer, U. S. Bureau of Mines, in the preparation of this paper.

Jan 1, 1930

By R. V. Mrazek

The heat of formation of vanadium trichloride was determined at 298.15° K. Measurements were made in a solution calorimeter in which an aqueous hydrochloric acid-potassium dichromate solvent was employed. Data are presented for the heats of solution of vanadium trichloride and the vanadium trioxide "backup" compound, and for appropriate dilution reactions needed to preserve stoichiometry. The resulting heat of formation of vanadium trichioride (VCI3) at 298.15° K was found to be ?H°298.15° K = -138.89 ±0.37 kcal/g mole.

Jan 1, 1968

By G. E. McElroy, A. S. Richardson

"Experiments in the determination of friction factors for fan-pipe installations were carried on in a Butte mine during the fall and winter of 1922-23, under a cooperative agreement between the Bureau of Mines and the Anaconda Ccpper Mining Co. The results have been summarized in a separate paper,*** and this report, which is one of several giving more detailed data, discusses the methods used and the application of the results to fan-pipe practice.The use of canvas and galvanized-iron pipe, 8 to 20 inches in diameter, with small fans, usually electrically driven blowers, is an important factor in the ventilation of metal mines and is increasing in coal mines and long tunnels. In the Matte district the standard installation is an electrically driven small blower fan and 8 to 16 inch canvas pipe.The application of available data on friction losses in sheet-metal pipe to mine installations was doubtful, and very little has been published on canvas pipe, except general statements that the friction looses are greater than in galvanized-iron pipe. Experiments by Weeks and others,**** who determined friction losses under laboratory conditions for a few typical materials used in mine equipment, supported the statements.In 1918, one of the authors (Richardson) conducted tests for the Anaconda Copper Mining Cc. on the friction losses in canvas-pipe systems and the beet type of centrifugal blower for use with such pipe lines. He obtained the average total resistance per unit of length in use, without reference to the variable conditions of the lines. The results were of great value in developing more efficient equipment for average service conditions, and indicated that average friction losses for the commercial canvas tubing then used by the company were equal to or lees than these given for galvanized-iron pipe. Later on, the particular canvas tested was discarded for a heavier and more service-material."

Oct 1, 1923

By L. A. Morley

Volume III of the final report examines the indication versus interruption procedures used on motion-drive power equipment, with emphasis on surface excavators. The report begins with a review of the electromechanical acid conversion used with the Ward-Leonard control system. Protection criteria for the drive-system components are then discussed. Fault sources and fault calculations for both the ac supply source and dc power loop are introduced to assist in discussing indication and interruption procedures. The subject is then expanded to examine the dynamic process of the machine and determine the effects of fault current and position of the machine to allow for an orderly shutdown. With this analysis, possible indication an interruption procedures are given for the four-quadrant duty cycle of excavators. The report concludes by introducing other mining operations that utilize similar motion-drive systems and also static (solid-state) drives and recommends further research in these areas, as well as a more detailed examination of the dynamic fault analysis for excavators.

Jan 1, 1982

By L. L. Oden

The Bureau of Mines has studied a number of processes to remove Cu from molten steel scrap with the objective of determining if any of the laboratory methods studied warranted in depth research investigations. Experimental approaches included oxidizing Cu from steel containing other metals that form stable mixed oxides with Cu (AI, Cr, Fe, Mn, Mo, and V), injecting the same metals as oxides to simplify the mechanism of complex oxide formation, partitioning Cu into alkali or alkaline earth silicate slags or oxide-moderated sulfides, and coremoving Cu and S by injecting active compounds of Ca and Mg. The most promising tests, producing nearly 0.3 pct Cu in the slag, used Ar injection of K20-moderated Na2S-FeS below the surface of molten steel containing about 0.6 pct Cu and protected by a CaO-SiOz slag; however, in depth research investigations currently are not felt to be warranted.

Jan 1, 1987