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By Laurance L. Oden

The Bureau of Mines is developing melting data for binary combinations of the alkaline earth fluorides and yttria to facilitate the formulation of slag compositions. The present report deals with the CaF2-Y203 system for which solidus and liquidus temperatures and solid solubilities were determined. The information is presented as the phase diagram. All specimen compositions were blended from high-purity materials and encapsulated in Mo or Pt20Rh prior toheat treatment. Liquidus temperatures were determined by ceramographic examination of heat-treated and quenched specimens. Solidus temperatures were determined by differential thermal analysis and by electron microprobe analysis of quenched specimens. Terminal solid solubilities were derived by parametric methods. The peritectic system was found to be pseudobinary due to the formation of yttrium oxyfluoride at temperatures near the liquidus. The peritectic point occurs at 7 mole pct Y203 and 1,438° ± 5°C. The terminal solid solubility of Y203 in CaF2 decreases from 7 mole pct at 1,438° C to 1 mole pct at 1,100° C, and the solubility of CaF2 in Y203 decreases from 9.5 to 7 mole pct over the same temperature interval.

Jan 1, 1970

This summary of State laws on explosives wag compiled primarily to ascertain what subjects relating to their control have been acted upon by each State legislature and, in general, how they have been treated. It does not Include any legislation passed after 1942, or any proclamations, regulations, or administrative orders. It does not purport or attempt to be authoritative. If any problem arises involving interpretation of the statutes of any particular State, the original source must be consulted for the exact words used by the legislature. This summary, however, will be useful in determining whether relevant statutes exist, and in locating them quickly, with a minimum of effort. It will be of value also in comparing statutes in other States to determine what construction has been placed upon them by the courts of these jurisdictions or to contrast the varying provisions of many States upon a similar subject. To make these comparisons easier, the statutory provisions for each State have been grouped under several major topics in outline form. Although this sometimes has resulted in disruption of the continuity of individual acts, the increased general clarity and availability of comparable sections have more than justified the procedure followed.

Jan 1, 1943

By E. K. Stanek

This research study was performed on a case study basis and can be divided into two parallel thrusts: electrical and thermal energy conservation. Energy consumed annually in mining and refining operations represents about 6% of the 80 quadrillion Btu's consumed nationally. In the electrical portion of the study, five areas were addressed: optimal dispatching of on-site generation, high-efficiency motors, conductor selection, power factor correction, and high efficacy lighting. In the case study mine which has a multiple unit on-site generation system, optimally dispatching units can save significant energy. The other four methods are difficult to justify on a retrofit basis due to capital costs. In the thermal portion of the study, a thermodynamic analysis was performed on the reverberatory smelting process possible areas of energy conservation were identified as radiation and convection heat losses from the furnace arch and the dumping of high energy content smelting slag. It has been shown that materials currently available can provide the means of reducing heat loss from the reverberatory furnace. It has also been shown that a significant amount of energy may be recovered from the slag. However, these are both subject to further study and validation.

Jan 1, 1982

By Rose L. Ballard

This chapter summarizes data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rico. Included also are the tables that show the principal nonfuel mineral commodities exported from and imported into the United States and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of volume I and in the State chapters of volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at any of several stages of extraction and processing, the stage of measurement used in this chapter is what is ordinarily termed "mine output." It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines.

Jan 1, 1983

By F. G. Horino

This report presents the theory and design of a stiff loading machine used by the Bureau of Mines. The machine incorporates three high-strength steel columns as the restraining member in parallel with the specimen. The theory presented gives the basis of design and the dimensions of component parts of the machine. Laboratory verification of the theoretical stiffness is described using three different setups involving a hydraulic jack and spacers and confirms the stiffness calculations to within 1 percent. Experimental techniques, testing procedures, and special equipment designed for determining the complete stress-strain behavior of NX cores of both hard and soft rock are described. Typical test data are presented as force-displacement curves for two rock types, a marble and a granite.

Jan 1, 1972

By L. C. IlsLey

Explosives have been fired electrically for several decades. Mountains have been tunneled, deep shafts sunk, extensive coal and metal mine workings excavated and, in times of war, railroads, buildings, bridges, and fortifications have been destroyed by means of electrically fired explosives. Modern engineering depends so much on explosives that their safe and efficient handling and especially their detonation are of prime importance to all those connected with the use of explosive agents. Electric shot-firing is only one method of igniting explosives, but it is rapidly spreading and because of certain inherent safety features should be encouraged. Data collected by the Bureau of Mines indicate that in the United States a large percentage of the blasting in quarries, shafts, and tunnels, and from 15 to 25 per cent of the blasts in mining operations, are set off electrically. The Bureau of Mines is interested in electric shot-firing because of its use in mining, and especially because electric methods, when properly applied, are undoubtedly safer than other methods commonly used.

Jan 1, 1926

By Thomas C. Denton

In 1965 Africa maintained its position as a region of the world essential to advanced non-Communist nations for supply of vital metals and minerals. The position stemmed from the fact that Africa produced in large quantity a number of key minerals of which either or both resources and production capacity elsewhere did not approach the needs of the free world. The Republic of South Africa alone contributed more than three quarters of the gold mined in the entire non-Communist world besides an estimated 60 percent of metals of the platinum group and the entire new supply of amosite asbestos, and Africa as a whole was nearly the non-Communist world's only source of gem and industrial diamond. Africa also accounted for 83 percent of non-Communist world cobalt production. Besides these massive contributions, Africa in 1965 provided 50 percent or more of the new supply from non-Communist countries of the following mineral commodities: Lithium minerals, corundum, manganese ore: and chromite, and over 20 percent of new supply from non-Communist countries of columbium-tantalum concentrates, antimony, beryl, vanadium, phosphate rock, and copper. Africa also accounted for 18 percent of the non-Communist world's output of uranium, 14 percent of its tin, 11 percent of its lead, 9 percent of its zinc, and 8.9 percent of its crude oil output. With respect to chromite, at yearend Africa's reserves of the mineral were far larger than those of all other non-Communist regions combined. This probably also held true for manganese ore. In the case of crude oil, the fact that Africa's share of non-Communist world output was 1.6 percentage points greater than in 1964 was significant, particularly inasmuch as the output rate was continuing to increase at yearend.

Jan 1, 1967

By F. D. DeVaney

The low-grade deposits of manganese ores along the Missouri River near Chamberlain, S. Dak., are known to contain one of the largest reserves of manganese in the United States. Manganese occurs as concretionary nodules ranging in size from 13 inches in their longest dimension to particles finer than 65-mesh. The nodules are embedded in soft, wet shale, which contains little manganese. The removal of nodules from the low-grade shale is a simple mechanical problem; the question is primarily to determine the lowest-cost method of separation. This report purposes to present data acquired by experimenting with samples of the ore, which form a basis for suggesting methods of concentrating manganese nodules.

Jan 1, 1942

By F. D. DeVaney

The low-grade deposits of manganese ores along the Missouri River near Chamberlain, S. Dak., are known to contain one of the largest reserves of manganese in the United States. Manganese occurs as concretionary nodules ranging in size from 13 inches in their longest dimension to particles finer than 65-mesh. The nodules are embedded in soft, wet shale, which contains little manganese. The removal of nodules from the low-grade shale is a simple mechanical -problem; the question is primarily to determine the lowest-cost method of separation. This report purposes to present data acquired by experimenting with samples of the ore, which form a basis for suggesting methods of concentrating manganese nodules.

Jan 1, 1942

By M. Beus, S. Inverson, B. Stewart

Abstract Recent ore pass failures have underlined the need for improved designs, standards, structural mon¬itoring methods and better hang-up prevention and removal tech¬niques. Researchers at the Spokane Research Laboratory of the Na¬tional Institute for Occupational Safety and Health (NIOSH) are investigating methods to improve safety during the transport of ore in ore passes. Design criteria and hang-up prevention and remedia¬tion strategies involve studies of the effects of static and dynamic ore and waste-rock loads on chutes, walls, gates and support structures. Particle flow analysis methods were used to simulate the response of various ore pass designs to a wide range of ore loading condi¬tions. A full-scale mockup of ac¬tual ore pass and chute assemblies was duplicated and tested for load response. Data from a particle flow code and the mock-ups were com¬pared Loads on an active ore pass chute were measured.

By J. J. Forbes

The activities of the Bureau of Mines include the development and testing of self-contained oxygen breathing apparatus and other devices for respiratory protection, the development and tasting of devices for detecting dangerous or noxious mine atmospheres, and the training of men in the mineral industries in the use and care of this equipment to enable them to render effective service in mine rescue and recovery operations following mine fires and explosions, or under other conditions where irrespirable gases may be found in mines or mining plants. The first use of self-contained oxygen breathing apparatus for com- bating mine fires and explosions in the United States dates back about 30 years. Previous to that time, exploration for any distance ahead of fresh air was virtually impossible without great risk to life; moreover, the men called upon to render service at mine disasters were not well-versed in the properties and physiological effects of gases likely to be encountered. It was also impossible to work ahead of fresh air to restore ventilation, and if many stoppings were blown out by an explosion, air had to be introduced into whole areas or sections at once without knowledge of the conditions ahead; moving an explosive mixture of methane and air over live fire had to

Jan 1, 1938

This report has been prepared in response to a request by the Bureau of Land Management (BLM) Fairbanks Alaska District Office that the Bureau of Mines quantitatively assess the potential supply of minerals from undiscovered deposits in the White Mountains National Recreation Area (WMNRA) and the western part of the North Steese National Conservation Area (SNCA) in Alaska. The assessment will be used to assist in future land-use decision-making. Resource Management Plans (RMPs) for the WMNRA and the SNCA were approved by the BLM in 1986. These plans imposed significant restrictions on new mineral development in the two areas. The level of public concern regarding these actions, especially on the part of the mining industry, has spurred BLM to seek additional information about the potential supply of minerals from the two areas with assistance from the Bureau of Mines. The assessment focuses on an area within the WMNRA and the SNCA which has been administratively closed to mineral entry. The study area encompassed approximately 1.24 million acres and included all of the WMNRA and the western portion of the North SNCA (fig. ES-1). Three quantitative estimates of the potential supply of minerals from the study area were developed: 1) For all lands in the study area, assuming that they are open to mineral entry-the baseline analysis; 2) For those lands which have been closed to mineral entry; and 3) For eleven prospective mineral activity areas, assuming that all are open to mineral entry.

Jan 1, 1989

By T. R. Achenbach

1. This, the final report to the U. S. Bureau of Mines on the program with the subject title, presents the data obtained from June 29, 1973, to April 20, 1974. 2. Operating in the Illinois #6 coal seam, the effectiveness of foam opposed to water was compared in reducing respirable coal dust. A combination of 39 foam generators and 14 water sprays were used during the foam tests. Sixty one water sprays were operated during the water tests. Data from 24 shifts using foam and 21 shifts using water are presented. 3. Additional work on foam generator design should be undertaken to provide coverage to a wider area with foam. 4. The general attitude of those working on the foam program and with the miner at the face was positive. It is urged that the work be continued. 5. The minor respiratory irritations evidently caused by an aerosol effect of the surfactant should be investigated. 6. The statistical analysis of the tests will be made and reported by the U. S. Bureau of Mines.

Jan 1, 1974

By Thomas M. Barczak

The initial Support Technology Optimization Program (STOP),Version 1.0, was released at the 19th Ground Control Conference. This original program has since been updated to Version 2.3 which was released in May, 2001. This paper describes the additional features of Version 2.3, focusing primarily on the following three aspects: (1) including uncontrolled convergence into the design requirements for standing roof supports, (2) the addition of design procedures for cable bolts as an alternative secondary roof support, and (3) the addition of new standing roof support technologies. Another new feature which should facilitate the development of design criteria for standing roof support is the capability to define ground reaction curves through convergence measurements alone without having to make support loading measurements. There are several other new features provided in Version 2.3 which are only briefly addressed in the paper. These include: (1) additional graphics capabilities to facilitate rapid assessment of support comparisons, (2)an East-West designation for support selection to more accurately provide cost and support availability data, (3) additional safety measures including a safety factor to identify support design near the peak support capacity, checks to see if the support dimensions comply with aspect ratio requirements, and a measure of roof coverage for the design layout of the support system. These new features of STOP provide more capabilities to design and analyze secondary roof support systems for conditions which could not be fully analyzed in the original version of the program.

Determine the advantages and operational limitations of water-let-assisted cutting used with mining equipment. Approach The Bureau of Mines con-ducted a research study to evaluate water-Jet-assisted cutting both in the laboratory and in underground mines. Earlier research on water-jet-assist was limited to laboratory studies where bit speeds and penetration depths were very low and large cutting force reductions were reported. For the past years, research by the Bureau of Mines and others has been concerned with the application of water-jet-assisted cutting under more realistic mining conditions. Study Results Water-jet-assisted cutting employs a mechanical cut-ting bit combined with a moderate to high-pressure water jet directed just in front of the bit tip to assist in the cutting process. Recent Bureau findings show that the addition of the water jet to the cutting bit can improve cutting in harder materials, significantly reduce respirable dust and bit wear, and increase product size. Some of these findings are presented as follows.

Jan 1, 1987

By T. H. Jeffers

The Bureau of Mines conducted a laboratory investigation of copper electrowinning from electrolytes produced by solvent extraction. The purpose of the research was to gain a better understanding of the fundamental relationship between copper electrowinning conditions, anode corrosion, and cathode purity. Processing variables were evaluated in a cyclic semicontinuous system in which the depleted electrolyte was used to strip copper from loaded organic extractant. For the production of high quality copper cathodes, the electrolyte was dosed with cobalt and stripped of organic solvent extraction reagent. An optimum cobalt addition of 60 ppm, and removal of the entrained extractant with activated carbon provided the best conditions for electrowinning copper containing the least amount of lead and controlling anode corrosion. As little as 13 ppm of the entrained organic extractant, LIX 64-N, significantly accelerated anode corro-sion. However, the addition of 1,000 ppm of organic diluent kerosine did not affect anode corrosion. After cobalt dosing and removing the entrained extractant, cathodes containing less than 2 ppm lead were consistently electrowon at widely varied current densities, electrolyte copper and acid concentrations, and temperatures. Dosing of the electrolyte with selected impurities including magnesium, aluminum, manganese, and iron did not affect the cathode purity. However, 0.05 giL of chloride ions markedly increased anode corrosion and the sub-sequent transfer of lead to the cathode copper.

Jan 1, 1985

By Kevin Connor

There was little change during 1988 in the production of minerals in Burundi. The Government of Burundi, which banned all commercial mining operations in the country in 1979, lifted the ban on mining of alluvial gold deposits and started a program of small-scale artisan gold mining in October. Along with the legal mining of gold, licensed gold trading counters were established. Other mineral commodities produced were kaolin clay, lime, and peat. In compliance with the Government ban, the only mineral wealth exploited for commercial sale and export was alluvial gold. Through financial assistance from the International Bank for Reconstruction and Development (World Bank) and the United Nations Development Program (UNDP), a study to inventory the country's mineral resources continued throughout the year. As part of this study, during the year, a West German company undertook a drilling program to further outline the nickel reserves of the Musongati area in central Burundi. Results of the work as of yearend were disappointing, with only 12 million tons of ore identified with better than 2% nickel content proven. Investigations also continued during the year regarding the centrally located deposits of vanadium-bearing titaniferous magnetite. A Norwegian company contracted to prepare a prefeasibility study for developing the deposit. The British Sulphur Corp. Ltd. was nearing completion of its $1.2 million2 study of the phosphatic limestone deposit at Matongo-Bandaga at yearend. Ore reserves of about 17 million tons grading 11% phosphorus pentoxide (P2O3) had been identified. The phosphate zone overlies a carbonatite rock, which could provide the basis for a cement industry. Additional drilling was planned for 1984. Exploration for gold was underway in 19S3 in northern Burundi through UNDP funding. Several primary deposits of shallow semimassive sulfides with gold values ranging from traces to 11 grams per ton had been discovered. With assistance from the Federal Republic of Germany, bastnasite reserves of 5,400 tons, with associated high europium oxide and cerium content, were verified, and the prospects for finding

Jan 1, 1985

By William H. Schiffbauer, Timothy Lutz, Michael R. Yenchek

The National Institute for Occupational Safety and Health (NIOSH) Pittsburgh Research Laboratory (PRL) participated in an experiment to facilitate the remote control of dozers used on coal stockpiles. The experiment consisted of supplementing the normal sensory cues an operator requires to manipulate the dozer from a remote location. NIOSH provided and tested a vision systems intended to give the operator the ability to operate the dozer safely and efficiently from a remote position. This paper highlights the genesis of the experiment, identifies the contributions of Consol Energy and Caterpillar, and details the NIOSH efforts and successful test results. Keywords-remote-control; vision system; stockpiles; safety

By Walter D. Holland

This is one of a series of instruction guides developed to help instructors present health and safety training courses to workers in the metal and nonmetal mining industry. This course is intended for training those, usually the safety officers, who perform surveys for inhalation contaminants in above ground work areas. The handbook entitled ?Handbook for Surveys of Inhalation Contaminants in Above Ground Metal and Nonmetal Mining and Processing Work Areas? is used as a manual for the course and as a prime reference when performing the actual surveys or interpreting the sampling results. There are six experiments for the students to perform during the course to familiarize them with the sampling devices routinely used during the surveys.

Jan 1, 2011

By John H. Johnson

This report covers research which is directed toward the measurement and control of underground mine diesel emissions. The report consists of three separate reports presented as Sections 1, 2, and 3. Section 1 "Emissions Measurement Apparatus" (EMA 1) discusses the selection and evaluation of instruments and procedures to be used as part of a diesel tailpipe emissions dilution and measurement apparatus. The instruments selected for gaseous pollutants are the Energetics Science Inc.* E.S.I.) 2000 for CO, the E.S.I. 7000 for NO and N02, and the Fuji ZFP5 for C02. Particulate matter is presently measured with the Celesco 1013 Smoke Opacity Meter. The raw exhaust concentration of one of these constituents is used Lo calculate the dilution ratio. Either a modified high range E.S.I. 2000 CO instrument or a Daco Products Cobra C02 instrument can be used, but neither is totally satisfactory. The study also indicated that it may he possible to increase the sample collection time from 15 seconds to the total 30 seconds over which the engine can be loaded without increasing the probability of damaging the vehicle hydraulic systems. Section 2 "The Effect of Fuels, Catalysts and a Filter Trap on Drift Pollutant Concentrations" discusses research in the Mine Air Quality Laboratory. A Wagner ST5D LHD with a Deutz F8L714 engine was used to compare three exhaust aftertreatment devices and a muffler-only system. The effect of these four systems on CO, C02, NO and N02 and on total, soluble, sulfate, and solid particulate matter was measured in the drift and on the LHD. The filter trap successfully reduced particulate matter for both fuels without significantly increasing the concentrations of any of the other constituents. The PTX catalyst was effective in reducing CO, and soluble particulate, but significantly increased N02 and solid and sulfate particulate matter. The Oxy Cat catalyst tested didn't seem to he working on the gases, and it significantly increased sulfate, soluble arid solid particulate concentrations. Section 3 "Diesel/Coal Particulate Matter Characterization by Laser Raman Spectroscopy" covers basic research on a method for determining the percentage by weight of diesel particulate on a filter containing a diesel-coal mixture. Signal-averaged Raman spectra provide the necessary precision. The method developed is non-destructive and uses as-received filters requiring no sample manipulation. Particulate with diesel contents in the range of 10 to 50% by weight have been analyzed with accuracies better than 6%t of the mean value. A number of samples containing diesel-coal mixtures were characterized by the procedures developed and the results are analyzed in light of various spectral and other system variables including coal rank and form and diesel engine operating conditions.

Jan 1, 1982