Search Documents

By S. H. Lorain

This paper briefly describes the principal commercial and near-commercial deposits of gold-bearing gravel and the important placer-mining operations in Lemhi County, Idaho. It is on of a series on western mining districts being published by the Bureau of Mines. This paper is based on a field survey of the placer-mining districts of Lemhi County in the summer of 1938. Available information concerning gold-bearing gravels was obtained from prospectors and claim owners; operators supplied the data on mining operations. No attempt was made actually to test the gravels. The principal object of the examination was to indicate placer areas worthy of further investigation by prospective operators.

Jan 1, 1939

By E. R. Maize

[he scconG rcport of :his st?rI.org 8cdt with o3servatioi:s of conver- gence of roof an4 floor at t!x*re: ?.cc.-.tioris iri til~ ClVucible mine of kke Cru- cib1.o Fuel Co. Data on sl:'ociacnce ?.rd Lztcrcl mwe:~cnt cf the surface were .:lven for two of these areas, a-12 it was mentioned that ~lr~~ilar data were being obtained on a ?art of Pe:sc:rlvtzr.ia Fii~l?trr.y FE:, ~i!lic;l pcser: over the third area. 'I'hie hichw~ :LEO FasseE over t!lc ITenncoli::. :.line of the Bnckeye Coal Co. 9 milcs to ';he so-lth, cnd at P. l~tcr C'..att: ~.nr?r.,cc?r:cntS *.rere mnd.e to make similar observati on3 there. This y: pr mrnmri:.c n Czto obtnino? at those two locetionn,]

Jan 1, 1941

By Nan C. Jensen

Modern high-temperature metallurgical processes have created a demand for raw material for furnace parts and lining that not only will with-stand high temperatures is but will not react with the substance being melted in the furnace. Spark-plug insulators, laboratory ware, tanks for the glassmaking making industry, and saggers and kiln furniture for the chinaware and pottery trades also must be made of materials hat have high melting points. Among the minerals that can be employed for such refractory uses ore those commonly known as the "sillimanite group' -kyanite, andaluste, sillimanite, and dumortierite - and the allied minerals topaz and pinite. Consideration of the occurrence, properties, qualities, uses, and sources of supply of these commodities and the markets for them constitute the subject of this paper. General Features of Kyanite and Related Minerals Kyanite, andalusite, and sillimanite ire composed of three elements - aluminum, silicon, and oxygen ? and are called aluminum silicates. The have

Jan 1, 1943

By C. L. Karr

Researchers at the U.S. Bureau of Mines (USBM) have developed adaptive process control systems in which genetic algorithms (GA's) are used to augment fuzzy logic controllers (FLC's). GA's are search algorithms that rapidly locate near-optimum solutions to a wide spectrum of problems by loosely modeling the search procedures of natural genetics. FLC's are rule-based systems that efficiently manipulate a problem environment by modeling the "rule-of-thumb" strategy used in human decision-making. Together, GA's and FLC's include all of the capabilities necessary to produce powerful, efficient, and robust adaptive control systems. To perform efficiently, such control systems require a control element to manipulate the problem environment, an analysis element to recognize changes in the problem environment, and an adaptive element to adjust to the changes in the problem environment. The control system also employs a computer simulation of the problem environment. Details of an overall adaptive control system are discussed. A specific laboratory acid-base pH system is used to demonstrate the ideas presented; all results are from the physical laboratory system and not from a computer simulation.

Jan 1, 2010

By Steven G. Grannes

This U.S. Bureau of Mines report summarizes Federal mandatory belt conveyor automatic fire suppression system installation requirements and inspection procedures, identifies system failure modes observed during in-mine investigations, and suggests system design and maintenance upgrades which, if implemented, would result in an improvement in overall system reliability. This report is a compilation of recommendations based on discussions with Mine Safety and Health Administration (MSHA) inspectors, review of manufacturer's literature, discussions with mine personnel, and research investigations of automatic fire suppression system performance in the laboratory and in mines. The Code of Federal Regulations (CFR) requirements for installation, inspection, and maintenance of fire suppression systems should be regarded as minimum standards.

Jan 1, 1990

By D. C. Seidel

This report describes generic procedures and equipment arrangements for conducting laboratory-scale hydrometallurgical and related waste-management experiments. It provides a starting point for personnel who have received or are receiving professional training, but do not have specific experience in laboratory procedures. With guidance, it also has application as a resource for technician training. The publication contains chapters on laboratory safety, feed-sample preparation, leaching, solids-liquid separation, and recovery from solution.

Jan 1, 1995

By NORA Mining Sector Council

The National Occupational Research Agenda (NORA) is a partnership program to stimulate innovative research and workplace interventions. In combination with other initiatives, the products of this program are expected to reduce the occurrence of injuries and illnesses at work. Unveiled in 1996, NORA has become a research framework for the National Institute for Occupational Safety and Health (NIOSH) and the United States. Diverse parties collaborate to identify the most critical issues in workplace safety and health and develop research objectives for addressing those issues. NORA entered its third decade in 2016 with an enhanced structure. The 10 sectors formed for the second decade will continue to prioritize occupational safety and health research by major areas of the U.S. economy. In addition, NORA’s seven cross-sectors will continue to focus on the major health and safety issues affecting the U.S. working population. While NIOSH serves as the steward to move this effort forward, it is truly a national effort. NORA is carried out through councils comprised of members with many diverse interests that are developing and implementing research agendas for the occupational safety and health community over the third decade (2016-2026) of NORA. Councils address objectives through information exchange, partnership building, and enhanced dissemination and implementation of evidenced-based solutions. NORA groups industries into 10 sectors using North American Industry Classification System (NAICS) codes. The Mining Sector encompasses NAICS code grouping 21xxxx where “xxxx” represents the different subcodes of the mining “21” classification. Mining encompasses the extraction of solid mineral and mineral-like substances from their place in the Earth’s crust and supplies them to processing industries that produce economically valuable materials. It does not include oil and gas extraction. The Mine Safety and Health Administration, MSHA separates mining into coal, underground and surface, and metal and nonmetal, underground and surface.

Feb 1, 2024

By H. E. Hilliard

A method was investigated for detecting and counting filamentous iron bacteria in open recirculating cooling systems. It is simple and fast and does not require trained microbiologists. Samples from 26 systems were examined. Cells were cultivated on commercially prepared ready-to-use media. Cultures grew well on this medium and were identified as filamentous iron bacteria by microscopic examination and by their ability to deposit iron using the prussian blue reaction.

Jan 1, 1976

By Russell R. Trengrove

The Copper Canyon lead-zinc mine is in the Battle Mountain. District, Lander County, Nev. It was discovered in 1866 and mined for copper until 1935 and for copper and gold until l948, when the main production became lead-zinc ore. The rocks in the area are carboniferous (Pennsylvanian and Mississippian) sedimentaries that have been intruded by quartz monzonite of Mesozoic age. They have been intensely folded, faulted, and tilted. Lead-zinc ore occurs as sulfides disseminated along fractured zones in a conglomerate arid hornfels. Development was carried out by the Bureau of Mines in cooperation with the U. S. Geological Survey and comprised a study of the geology, making maps and. cross sections, and exploring the deposit by diamond drilling from underground. Eighteen holes were drilled, for a total of 2,594 feet. This report contains a brief history of the property and a description of mining methods and beneficiation of the ore, geology, ore deposits and drilling done by the Bureau of Mines. It also contains detailed analyses of the ore samples taken and logs of the holes drilled.

Jan 1, 1951

By Forrest T. Moyer

The overall disabling work injury experience, excluding office- workers, at nometal mines and mills during the period 1961-63, as reported to the Bureau of Mines by operators, was 77 fatal and 7,201 nonfatal injuries during an aggregate worktime of 335,029,685 man- hours. These injuries, fatal and nonfatal combined, occurred at a frequency rate of 21.72 per million man-hours, comprising 0.23 for the fatal and 21.49 for the nonfatal injuries. The combined severity rate of the disabilities was 2,312 days lost or charged per million man-hours, consisting of 1,379 for the fatal and 933 of the nonfatal injuries, The average severity of all disabilities during 1961-63, was 106 days per injury, The number of days lost or charged, excluding officeworkers, at nonmetal mines and mills during 1961-63, was 462,000 days charged to fatal injuries and 312,461 days lost from nonfatal injuries. The outstanding causes for fatal injuries were explosions (18 fatalities occurred in a major mine-explosion disaster in a potash mine in Utah in 1963) and falls of rock or ore from back or side, while most nonfatal injuries were caused by handling materials, slips or falls of persons, haulage, and machinery. The parts of the body most frequently injured during the period 1961-63 were the trunk, hand and finger, and foot and toe, An average of 52,810 men were at work daily, There were 20 nonfatal disabling injuries reported for office- workers at nonmetal mines and mills during the period 1961-63 during an aggregate worktime of 23,088,496 man-hours, These injuries occur- red at a frequency rate of 0.87 per million man-hours, There were no fatal injuries reported.

Jan 1, 1967

By W. R. K. Wu

Results of linear correlations of two to four variables by the least-squares method are presented. The variables include 63 parameters representing coal composition, coal plasticity, and coke strength. The composition parameters are on chemical analyses; the plasticity parameters, on three plastometer and dilatometer tests and four miscellaneous tests; and the coke-strength parameters, on three ASTM indices. Seventy-two to eighty-four plastic coals were used in the plasticity and carbonization tests, which together form the basis of this report; 43 nonplastic or weakly plastic coals were used in the coal-band studies. Plots of relations between volatile matter, carbon, and oxygen contents of 1,860 U.S. coals and the 84 coals used are shown. Similar plots between volatile matter and hydrogen or atomic H/C of the 84 coals are also included. Significances of regression coefficient signs for coal composition parameters in the significant correlations found are discussed. Based on these significances, the following relations are shown: (a) coke strength versus average aromaticity, or mineral matter content, of the parent coal; (b) characteristic temperatures of the plastometer and dilatometers, the free-swelling index, or the Gray-King type versus average hydroaromaticity of the coal; and (c) nontemperature parameters of the plastometer and dilatometers versus the physical properties of a certain group of compounds from thermal decomposition of coal. Similarly, significances between the positions of coals in the coal band and the aforementioned relations are also discussed. A structural theory of coal plasticity is proposed. Applications of the correlation results are discussed. Composition parameters, such as carbon, atomic H/C, and calorific value may be used as a basis for selecting coking coals for stronger coke. Plasticity parameters, such as the end temperatures of the plastometer and dilatometers and the free-swelling index, may be used for the same purpose. Based on the best correlations found, coke-strength indices may be estimated to within 4 to 8 units of the observed values; the end temperatures of the plastometer and dilatometer tests, 5° to 10° C.; and the free-swelling index, within 1 unit. Accuracies of all these estimated values are examined, based on the experimental errors of the data involved. Finally, estimations of plasticity parameters from one test with those from others are shown.

Jan 1, 1971

By James F. O'Neill

Brown iron ore resources in Barbour , Butler , Crenshaw , and Pike Counties were investigated in a drilling program and geological study by the Federal Bureau of Mines in cooperation with the Alabama Geological Survey and the University of Alabama . The aggregate footage drilled was 18,010 linear feet . When developed , reserves of 12,664,000 long tons of crude ore were indicated , containing from 26.9 to 29.0 percent iron and 0.2 to 1.6 percent manganese under a maximum overburden of 40 feet . Total inferred crude ore for the four counties was calculated to be 827,700,000 long tons . Beneficiation of samples by simulated log washing and use of a 1 / 8 - inch screen yielded from 46.8 to 51.7 percent iron and 0.2 to 2.6 percent manganese . Screen- test studies indicated no appreciable interlocking between the iron and manganese minerals and the waste particles of materials retained on a 200 - mesh screen . Clay was prominent in micron - size slimes . Silica was deleterious in the minus 20 - mesh size . While an indicated 2,198,000 dry long tons of usable iron ore can be recovered , sink - and - float tests show that it may be possible for 4,654,000 dry long tons to be recovered by other than log washing . However , applicable commercial processes have not been demonstrated .

Jan 1, 1965

By Louis H. Berkelhamer

"INTRODUCTION ""Free silica"" includes all free forms of silicon dioxide, such as quartz, chalcedony, tridymite, cristbbalite, opal, diatomaceous earth, and lechatelierite. The term, has been used rather loosely however, as synonymous with quartz, as quartz is the most abundant form of free silica. ""Combined silica,"" on the other hand, has been reserved to denote silica combined with other elements as silicates.Improvements in methods for the determination of free silica, and quartz in particular, have been the subject of considerable interest during the past decade, owing mainly to the accented and increased knowledge concerning quartz as a causative factor in silicosis. Analysis for quartz, however, is of importance in many other fields, including the determination of quartz in ceramic raw materials, such as feldspar and clay; the evaluation of a beneficiation procedure by the ore dresser, such as in the concentration of iron ore; control studies of a manufactured product, such as silica brick; and routine analysis of rock, mineral, and ore samples by chemists and petrographers."

Jul 1, 1944

By P. C. Tully

The vapor pressure-temperature relationships for saturated pure liquid nitrogen are calculated by the Strobridge equation using a digital computer. This information is presented in two tables: first) in pressure increments of 0.1 psi from 1.8 to 492.9 psia) and second) in temperature increments of 0.1° from 63.15° to 126.26° K. These tables should facilitate the calibration of temperature-measuring devices over this temperature range.

Jan 1, 1967

By R. V. Higgins

The, large volumes of low A. P. I. gravity oil that will remain in many shallow fields of California when such oils no longer can be recovered profitably by pumping are important potential sources of oil when ways and means are found to remove them from the reservoir sands. Estimated ultimate oil recoveries in many of the "low-gravity fields" of the San Joaquin Valley in California indicate that less than 25 percent (on the average) of the original oil will be recovered. These oils have viscosities of 1,000 or more centipoises at reservoir temperatures and, because of their high viscosity and low intensity of the reservoir pressure, the quantities that will be retained in the sands ultimately are so large and their recovery is such a challenge to petroleum engineers that the Bureau of Mines has made the study of their possible recovery one of its major projects. The fact that a slight increase of temperature materially reduces the viscosity of low A. P. I. gravity oils has 'prompted the use of various means for increasing the temperature of the oil in the reservoir sands and hence the rate of flow and Completeness of recovery of the oil. Hot oil, hot water, heated air, and natural gas, steam, super-heated steam, and the products of combustion have been circulated in wells to raise the temperature of the oil it the sands; electric heaters have been installed in wells, and butane and air have been intermittently exploded and the flames propagated through the tubing to the "pay" zones. None of the methods, however, have been entirely satisfactory for the recovery of large quantities of oil.

Jan 1, 1949

"These tentative coal mine inspection standards have been prepared as a guide for the Federal inspection of coal mines of the United States. Much time and thought have been spent by various members of the Safety Division in the preparation of thses standards, and it is believed that compliance with them eventually will be possible in most mines. In many instances objections will be raised to them owing to long-established mining customs and practices that are inherently of dubious safety and to a natural inclination to oppose change. In other instances there will be valid objections due to conditions not foreseen at the time these standards were prepared. Or there may be substandard conditions and practices due to original mine layouts that it is not practicable to change during the lifetime of the mine; in such instances it is likely that some effective measures are or can be taken toward lessening hazards.With the rapid change in mining methods some of the standards may become inapplicable and it may be advisable to revise them to meet the new conditions. Therefore, questions regarding these standards and suggestions regarding new standards should be brought to the attention of the supervising engineer of the Coal Mine Inspection Division so that modifications of and additions to these standards may be made from time to time.In many respects these standards exceed the provisions of the various State mining laws, and some may conflict with the laws of some States. In cases of conflict, the intent is not to advocate noncompliance with State laws but to suggest that it may be desirable for the State to reconsider such laws or safety orders.Although an effort has been made to word these standards so that they may be readily understood, nevertheless, a reasonable interpretation should be placed upon them. In fact, in numerous instances the words reasonable"", ""suitable"", and ""properly"" are used in recognition of the fact that reason- and sound judgment enter into the carrying out of the safety endeavor.The policy of the Bureau on some vitally important safety matters in mines is set forth in its published Safety Decisions. These decisions have been consulted and used in the preparation of these standards. These decisions also are now being reexamined by its Mine Safety Board."

Feb 1, 1942

By Leonard F. Heising

At the Groveland-mine iron ore is mined by open-pit methods and concentrated by means of spirals and flotation. A brief history of the mine and its early development is given. The ore deposit is described, with emphasis on those physical characteristics that affect the choice of mining and milling methods. Development and mining, which include breaking ground, loading, transportation, engineering, and operating control; are explained, and the milling method is described Mining and milling costs are given in percent of total cost.

Jan 1, 1963

By C. Harry Benedict

This paper presents the details of milling practice and costs at the conglomerate mill of the Calumet & Hecla Consolidated Copper Co., Lake Linden, Mich., and is one of a series on milling methods being published by the Bureau of Mines. GENERAL DESCRIPTION The mines of the Calumet & Hecla. Consolidated Copper Co. are located in the Keweenaw Peninsula of northern Michigan. The mines of this district lie in a belt not over 4 miles wide and 100 miles long, which contains more or lees commercial ore. The Calumet & Hecla properties are the farthest north, except for the Seneca, of the operating mines. The district borders on Lake Superior, and by means of the Portage and Torch Lake waterways the largest lane vessels, can transport coal and other supplies from the lower Lakes directly to the company docks.

Jan 1, 1930

By Claude W. Sill

In the usual volumetric determination of uranium, the solution containing uranium is reduced in a Jones reductor, yielding a mixture of trivalent and tetravalent uranium; the trivalent uranium is oxidized to the tetravalent state by bubbling a stream of air through the solution. The resulting solution of. Tetravalent uranium is titrated with a standard oxidant, generally sulfatoceric acid, dichromate, or permanganate; It seemed likely that the, same general procedure could be used in determining semimicro quantities of uranium if the conditions affecting the variables involved were understood more clearly than at present. In the method described below, the use of ferric sulfate to oxidize tetravalent uranium allows the titration to be made at room temperature in an essentially colorless solution with sulfatoceric acid. The latter oxidant its turn permits the use of the very stable indicator, ferroin, with its sharp color.., change and exactly reproducible blanks. Solutions of uranyl sulfate were prepared by diluting a stock solution that had been standardized gravimetrically according to the method of Lundell and Knowles (8).3/ Solutions of sulfatoceric acid were prepared according to the directions of G. F. Smith (12) and were standardized against arsenic trioxide in the presence of osmic acid according to the directions of Gleu. The cerium solutions were stored in 18-liter carboys fitted with siphon arrangements so that the bottles did not need to be opened and protected from light in a dark cupboard. Under these conditions, even the 0.01 N solution changed by less than 1 part per thousand over a period of about 6 months.

Jan 1, 1952

By Keith S. Olson

During 1982 and 1983, the Bureau of Mines concentrated its fugitive dust control research on haulage road dust suppression by newer chemi-cals relatively unknown in the mineral industry, innovative dust control designs for haulage trucks, chemical tailing basin stabilization, and combined chemical and vegetation tailing basin stabilization. Relatively unknown dust suppression chemicals and innovative aerodynamic modifications to haulage truck fender designs were tested on a Minnesota sand and gravel operation haulage road. Magnesium chloride salt at 95-pct control efficiency and a petroleum derivative at 70-pct control efficiency were effective in suppressing dust generated by haulage vehicles; however, none of the fender modifications were successful. Commonly used dust suppressant chemicals were tested on a Minnesota taconite tailing basin to reduce the dust lift-off during the spring and fall dry seasons. The most successful chemical was lignin sulfonate with a seasonal cost of less than $200 per acre to achieve 90-pct dust control. When chemical treatments for immediate dust control were com-bined with revegetation for permanent control, the most promising chemical treatment based on vegetation response was lime-neutralized lignin sulfonate.

Jan 1, 1987