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By Robert B. McElwaine

"The demand for barite has increased greatly in the last 10 years, especially during World War II. Depletion of oil reserves and subsequent increase in deep drilling created a heavy demand by the oil industry for barite to be used as drilling mud. The great increase in demand for barite gave impetus to the development of a, deposit of impure barite near, Magnet Cove in Hot Spring County, Ark.The critical condition of the national barite supply early in 1944 led the War Production Board to recommend that the Bureau of Mines attempt to prove the existence of a large reserve tonnage of barite in the Magnet Cove area and arch for new deposits. To carry out this program, the Bureau explored on newly reported. Barite deposits in southern Montgomery County, Ark. The Gap Mountain, Fancy Hill, and Sulphur Mountain barite deposits were investigated. Eight diamond core-drill holes and 1,336 linear feet of surface trenching were completed, and barite samples obtained were analyzed, A study of the Montgomery County barnse district indicates that the lenticular bodies of barite replace a favorable host rock near the base of the Stanley shale formation. Barite is exposed along the side of anticlinal mountains where erosion has truncated the beds on the limbs of the associated synclines. An appreciable amount of barite suitable for commercial use has been indicated by trenching and core drilling. The Gap Mountain and Fancy Hill deposits are controlled by the Magnet Cove Barium Corp. and Baroid Sales Division of National Load Co., respectively. The ore is similar to that of the Magnet Cove area and is amenable to concentration by a flotation process. Mining of these deposits had not been begun by the time the Bureau completed its exploration project."

Nov 1, 1946

By W. H. Oppelt

Converting small-particle lignite to a stable, storable fuel of relatively high heating value was investigated. The fuel was prepared by thermal pretreatment of the lignite in an 8-inch i. d. rotary-drum retort, then the pretreated material was pelletized in an experimental 15-inch-i. d. rotary-drum pelletizer. Pelletizing tests were made with both starch and bituminous binders. During the first phase of the project, the quantity, composition, and heating value of products from the thermal processing of Kincaid lignite from Burke County, N. Dak., in an B-inch i. d. rotary-drum retort were investigated at a series of temperatures from 250° to 950° F. to establish optimum conditions for preparing feed material for pelletizing. To determine the response to thermal treatment of different lignites, 5 other lignites from Divide, McLean, Mercer, and Stark Counties, N. Dak., and 1 lignite from Saskatchewan, Canada, were processed at 700° F.

Jan 1, 1958

By B. H. Eccleston

The effect upon automobile emissions in changing from leaded to lead-free gasolines was studied in experiments by the Bureau of Mines in cooperation with the American Petroleum Institute. Typical U.S. leaded gasolines and prototype lead-free gasolines of comparable octane quality were used in eight vehicles operated to simulate city driving. The experiments were run at 70° and 95° F. Exhaust and evaporative emissions were measured and the photochemical effect of the emissions was experimentally observed in an artificial smog chamber. Results of the study reveal the manner and degree in which the changes in fuel composition alter the amount and characteristics of both exhaust and evaporative emissions. Briefly, it is shown that the compositional differences between leaded and prototype lead-free fuels resulted in higher photo-chemical pollution potential of the emissions from the lead-free fuels. The effect is attributed to the photochemical characteristics of high-octane fuel components that are used in greater quantity in the lead-free fuels.

Jan 1, 1970

By D. J. Bauer

Oxidation of mixed lanthanide solutions with ozone at pH 4.5 and at ambient temperature resulted in precipitation of 98 percent of the original cerium present. Corresponding cerium purity was increased from 50 to 98 percent. A second ozone oxidation-precipitation step produced cerium of 99.9 percent purity in high yield from the 98-percent-pure material. Alternately, ozonation at pH 6.5 and 85° C differentially precipitated cerium and rare-earth elements heavier than cerium and left 89 percent of the original lanthanum in solution at a purity of 95 percent. Subsequent recovery of cerium from the heavier rare-earth elements in the precipitate was accomplished by dissolving the precipitate in dilute mineral acid and reoxidizing the cerium with ozone at pH 4.5 and at ambient temperature. The filtrate contained an enriched praseodymium-neodymium-samarium-europium mixture that is amenable to separation by ion exchange or solvent extraction.

Jan 1, 1968

By M. J. Ankeny, J. J. Forbes

"One of the main functions of the U. S. Bureau of Mines, as authorized by Congress, is to investigate safety and health conditions, to disseminate information regarding safe and unsafe practices in mining, and to aid in improving safety and health conditions of mining communities and in promoting the welfare of the miner. Among several methods of reaching the miner and interesting him in safety work, perhaps the most effective is through the 11 mine safety stations and 11 railroad cars known as mine rescue, or more correctly, mine safety cars.Frequently, the Bureau of Mines receives requests for information regarding the purpose, equipment, personnel, and construction of its safety cars used in the field service. It is the intention of this circular to present to the mining public in particular, and to the public in general, some definite information regarding these safety cars and their functions.The cars are operated throughout the mining fields of the United States and are headquartered as follows (see fig. 1): Car 1, Reno, Nev.; Car 2, Raton, N. M.; Car 3, Pittsburgh, Pa.; Car 4, Terre Haute, Ind.; Car 5, Pineville, Ky.; Car 6, Pittsburg, Kans.; Car 7, Huntington, W. Va.; Car 8, Duluth, Minn.; Car 9, Butte, Mont.; Car 10, Des Moines, Iowa; Car 11, Anchorage, Alaska.One of the most important purposes of the U. S. Bureau of Mines safety cars is to render service at mine fires and explosions where human life is endangered. State mine inspectors and other interested persons are supplied with itineraries of the car operating in their districts from time to time, so that they may know at all times where the car can be found in case of emergency. When these disasters occur the car may be reached direct or through its field headquarters, and upon receiving word of a mine disaster, or request for assistance, it immediately proceeds to the scene of trouble. Frequently a special locomotive is supplied by the railroads and in many instances the movement of the car is given the right of way over all other railway traffic. Upon reaching the destination, the facilities and personnel of the car are immediately available for rescue and recovery operations.Following most mine disasters a thorough investigation is made by engineers of the Bureau of Mines, and a confidential report is submitted to the operator. The information gained in this manner from a large number of mine fires and explosions, together with the knowledge gained from the experimental work carried on at the Experimental mine of the bureau at Bruceton, Pa., serves as a basis upon which the bureau is able to recommend preventive measures whereby similar occurrences may be averted. The bureau car is often used as headquarters for the investigating engineer when such an examination is being made."

Mar 1, 1931

By G. S. Rice

The recommendations of the Bureau of Mines on rock-dusting practices are embodied, except in a few details, in the Recommended American Practice for Rock-Dusting Coal Mines to Prevent Coal-Dust Explosions,5 approved by the. American Engineering Standards Committee,6 December 30, 1925 It is specified that the dust to be used is of a size that all will pass through a sieve having 20 meshes per linear inch and that 50 per cent or more will pass through a sieve having 200 meshes per linear inch.

Jan 1, 1930

By Thomas H. Dubaniewicz

The National Institute for Occupational Safety and Health, Pittsburgh Research Laboratory conducted a study of laser safety in potentially flammable environments. Researchers measured threshold igniting powers as a function of beam diameter for butane and propane-air mixtures by laser-heating targets placed on optical fiber tips using a 1064 nm laser. The minimum igniting powers for propane-air and butane-air were about 250 and 300 mW, respectively. Threshold igniting powers for propane-air were approximately proportional to beam diameter for beam diameters from 0.1 to 2.0 mm. Results suggest that relatively powerful beams may be used in these atmospheres without causing ignition, provided the beam diameter is controlled. Threshold ignition delay times using 91125 and 62.51 125 pm fibers were approximately proportional to the inverse square of the laser power. Ignition delays were about 45 ms or longer for laser powers up to 800 mW. Preproduction samples of a commercial optical fuse prevented ignitions under selected test conditions. A self-healing effect was observed for one sample. Comparisons are made with the results of other researchers. O 2006 Laser Institute of America. Key words: propane ignition, butane ignition, laser ignition, nonbeam hazards, fiber optic fuse

May 3, 2006

By Dean H. Ambrose

[Mining and processing earth's materials form the basic building blocks from which many technology advancements and products are made. Virtually all metallic and non- metallic products are derived from a substance found in our earth that we blend, mold, extrude, or pulverize into something useful, the mining industry is responsible for the first step of this process: extraction from the ground. Mining particularly coal mining. poses significant risks to both humans and machines. As raw materials are]

Jan 1, 2009

By J. Burlin Johnson

This report describes an investigation of the relationship between crater dimensions formed in laboratory blasting experiments and the mechanical properties of the material cratered. Scaled field data have been included when available. The results show that tensile strength and possibly other mechanical properties may be useful in predicting maximum crater dimensions.

Jan 1, 1963

By E. P. Youngman

This paper is one of a series of digests of foreign mining legislation and court decisions that is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate-mines in various foreign countries. This interpretation of the mining laws of Greece was prepared from information furnished by Ralph B. Curren, American assistant commercial attache, Athens, in reply to a questionnaire of the United States Bureau of Mines, transmitted through the courtesy of the commercial laws division of the Bureau of Foreign and Domestic Commerce. INTRODUCTION In his report,3 Mr. Curren states that the source of his information was the Director of Mines of the Greek Ministry of National Economy and the Mining Code of Greece, which was, compiled from existing laws in 1929,4 and which has since been modified by several acts of Parliament.

Jan 1, 1932

By Susan M. Moore

Many challenges are faced by workers in lower-seam (42 inches or less) mines. The lower-seam heights confine mine workers to their knees as they perform their daily tasks such as installing roof bolts, delivering supplies, repairing belt, or cutting coal. Miners working in these lower seams often consider kneepads to be their only line of defense against knee injuries. However, healthy knees do not start and stop with kneepads. Other interventions such as changing postures, proper hygiene, and work station design may also be used to reduce mine workers? risks for developing knee injuries. Incorporating these and many other interventions into a mine worker?s ?way of life? is an important step to ensuring a long, healthy career and retirement. Keeping knees healthy is also a key aspect to reducing costs in low-seam mines as the industry battles rising health care costs, and training/recruitment of replacement workers is time-consuming and costly. Educating the workforce about the possible interventions to reduce knee injury risk is a primary objective for the National Institute for Occupational Safety and Health?s (NIOSH) Pittsburgh Research Laboratory (PRL). Therefore, NIOSH researchers, along with industry and academia, developed a training package to educate the mining com­munity about some possible interventions beyond kneepads that may be used to help decrease knee injury rates. Increased awareness and simple changes are the first steps to reducing knee injuries.

Jan 1, 2008

By Mark S. Redfern, Kim M. Corneliusa, Christopher A. Hamrick, Sean Gallaghera

Coal miners often handle heavy electrical power cables, weighing up to 10 kg per meter. These cables are manually lifted and attached to the mine roof to prevent damage from mobile underground equipment. Data suggest that workers who commonly perform cable handling tasks experience a high rate of lost time back injuries. In this study, six male underground miners performed a total of 12 cable-hanging tasks in standing, stooping, and kneeling postures, during which kinematic and ground reaction force data were collected. Reductions in vertical work space were found to result in a linear increase in the peak moment experienced by the lumbarspine (p<0.05). In restricted postures, peak moments were not significantly different in stooping vs. kneeling postures (p>0.05). Average lumbopelvic flexion during the tasks was highest in stooping conditions, followed by standing and kneeling exertions (p<0.05). Implications of this data with respect to design of cable handling tasks are presented and discussed. Keywords: Biomechanics, posture, low back pain, restricted workspace, mining

By M. H. Kline

The Great Gossan Lead in Carroll County, Va., is one of the largest undeveloped sulfide ore bodies known in the eastern United States. It extends for 16.7 miles along the western slope of the Blue Ridge Mountains (fig. 1). The various known segments of the deposit, extending from the southwest end to the northeast, are: The Great Outburst or Iron Ridge segment, Chestnut Creek, Copperas Hill, Sarah Ellen, Wild Cat, Cranberry, Dalton Hill and offset segment to the south of the Cranberry, Little Reed Island, Little Vine, and the Betty Baker at the northeast end. All of these segments have been explored or mined to various extents in the past for the iron gossan and secondary copper ore. The Great Outburst or Iron Ridge segment is now being mined by the General Chemical Division of the Allied Chemical & Dye Corp. for the sulfur and iron content of the primary ore. These deposits are becoming increasingly of Interest as a. large potential source of iron and sulfur owing to their proximity to Birmingham, where the burned cinder sells at a premium, and to the acid markets of the region.

Jan 1, 1949

By K. R. Dorman

To develop the potential of precast concrete sets as a support medium in underground mines, a three-piece precast concrete drift set was designed for a small opening and tested to destruction in an underground straining frame. Thirty-six tests were made with three sizes of members using three different loading conditions. In addition, 14 members were tested individually in the laboratory. Test results are compared with theoretical calculations. A cost comparison shows the use of concrete sets would be advantageous where conventional wooden timber requires excessive replacement.

Jan 1, 1968

This publication summarizes the in-house and contract research projects programmed for fiscal year 1984 by the Bureau of Mines under its Conservation and Development activity. The document provides a mechanism for interested parties to gain insight into projects of the Bureau&apos;s Conservation and Development research program. The objective of the Conservation and Development Program is to provide the technological advances needed to stimulate the mining of domestic deposits containing critical, strategic, and other essential minerals in compliance with existing regulations and at costs sufficiently low to be competitive in world markets. Research efforts are directed toward improving the fundamental understanding of processes and procedures involved in the production of minerals. The overall goals will be accomplished by investigating alternative mining methods to increase domestic production of critical and strategic minerals from low-grade deposits; expanding the technology for the economic and efficient extraction of minerals consistent with cost-effective compliance with environmental regulations; and advancing the technologies needed to insure an adequate supply of coal.

Jan 1, 1984

In presenting this list of permissible explosives and blasting devices, the Bureau of Mines desires to call attention to pages 19 and 24 outlining, the conditions in use under which, and only under which, the explosive or blasting device is permissible. In view of a recent publication recounting trade practice favoring the use of a blasting device without stemming, particular emphasis is placed upon condition 4 on page 19 and condition 2 on page 24. An explosive or a blasting device enumerated in the permissible lists of this Bureau is not permissible in use unless it is properly confined with clay or other incombustible stemming.

Jan 1, 1940

In presenting this list of permissible explosives and blasting devices, the Bureau of Mines desires to call attention to pages 19 and 24 outlining, the conditions in use under which, and only under which, the explosive or blasting device is permissible. In view of a recent publication recounting trade practice favoring the use of a blasting device without stemming, particular emphasis is placed upon condition 4 on page 19 and condition 2 on page 24. An explosive or a blasting device enumerated in the permissible lists of this Bureau is not permissible in use unless it is properly confined with clay or other incombustible stemming.

Jan 1, 1940

By Russell R. Trengove

The largest potential reserves of manganese in Nevada are in the Pioche district. To date, these large reserves of 10-to l2-percent manganese cannot be upgraded economically. Other large, low-grade deposits, such as the Virgin River and Boulder City deposits in Clark County, cannot be considered immediate sources of manganese. Reserves of the principal manganese deposits in Nevada, based on the most reliable estimates, total about 17 million tons analyzing 7.6 to 13.6 percent manganese. Most of the deposits are of a type that cannot be prospected systematically but have been prospected and developed in the course of productive mining operations. To realize production from low-grade deposits that are amenable to concentration, a ready market must be provided. Thus far, Government stockpiles have been the major outlet for these low-grade ores. Research and experimentation over a period of years have led to development of several processes technologically applicable to these low-grade ore bodies, but their economics is not sufficient to allow competition with imported ores on the open market.

Jan 1, 1959

By E. L. Rawlins

Systematic leakage surveys of natural-gas transmission lines not only aid in the conservation of gas, but can be made to show direct financial returns of large magnitude. 1. Such surveys reveal the actual leakage from the lines, and indicate repairs to be made in order, to eliminate unnecessary waste. 2. Tests on lines, after repairs are made, show the actual saving that has been accomplished. 3. Tests on newly constructed lines reveal the presence of leakage that should be eliminated before the lines are put into service.

Jan 1, 1926

By S. L. May

Procedures for separating columbium and tantalum have been developed by the Bureau of Mines as part of a broad research program on the utilization of low-grade ores of columbium and tantalum, Columbium and tantalum compounds of greater than 99 percent purity have been obtained by application of the solvent extraction separation system: Hydrofluoric acid-sulfuric acid-methyl iso-butyl ketone. This system is unique in that it not only separates columbium from tantalum, but also separates these two metals from other metallic impurities. The system is effective for separating the metals irrespective of the tantalum and columbium ratio of the starting materials. Investigations in which the spent feed obtained from the initial coextraction step was recycled to the system indicated that efficiency was increased, and cost was reduced without impairing product purity. Continuous tests demonstrated that this solvent extraction system could be used in large-scale equipment without loss in efficiency or in purity of products. The separation of columbium and tantalum has been difficult because of the similarity in their chemical bahavior. Many methods have been proposed for separating these two elements, but most methods either did not achieve satisfactory separation or were tedious and time consuming. The Marignac process (3, 4)4 developed in 1866 was the only method used commercially until recently. This separation procedure is based on the difference in solubility in aqueous solution of potassium tantalum fluoride and potassium columbium oxyfluoride. Current commercial practice appears to favor solvent extraction as a method for separating tantalum from columbium (1). Several efficient methods for separating columbium from tantalum by solvent extraction (2, 9, 8) were reported earlier from this laboratory.

Jan 1, 1961