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By Ronald T. Mayerle

In-1992, the U.S. Bureau of Mines conducted a mineral investigation of the Anderson Mountain study area, including RARE II area 4-942, in Lemhi County, Idaho. The 7,340-ha study area lies within the Salmon National Forest about one kilometer north of the old mining town of Gibbonsville (pop.: 100). The eastern boundary of the study area is formed by the crest of the Bitterroot Range. The crest also serves as the continental Divide, and as the border between Idaho and Montana. The study area lies within the Gibbonsville Mining District, an important past producer of gold from lode and placer deposits. Since the 1870's, several hundred claims for both types have been located in the study area. Thirty-six current (1992) lode claims and two patented claim groups (one lode and one placer) are wholly or partially in the study area. No placer claims are current. In all, twenty-seven lode and five placer properties in and adjacent to the study area were investigated. Workings on the properties included 2 caved shafts; 36 caved adits; 8 open adits; 120 small pits, cuts, and trenches; and 4 large dozed cuts.

Jan 1, 1993

By E. Lee Bray

"Editor’s note: The editors thank those who make this annual issue possible. A special thank you goes out to the Industrial Minerals Annual Review editor, to the Industrial Minerals & Aggregates Division Technical Committee chair and vice chairs, and to the authors of the individual commodity profiles.Jim Norman, member SME, of Tetra Tech Geo, is the industrial minerals annual review editor. Edgar Blanco, member SME, of Freeport- McMoRan, is chair of the Industrial Minerals &Aggregates Division’s Technical Committee.The technical committee vice chairs include:• NickTushar Gupta and Sallie Gaillard, of the USGS, members SME, agricultural materials.• Abhishek Choudhuryand Xihui Yin, members SME, of Montana Tech and Kemira, repectively, ceramic and refractory materials.• Bobbi Strange and Riddhika Jain, members SME, of Outotec, Martin Marietta and Outotec, respectively, chemical raw materials.• Snehamoy Chatterjee, Alyssa Kendir and Alind Chandra, members SME, of BMT, Universityof Kentucky and Michigan Tech, respectively,construction aggregates.• Subham Verma, Gauran Soni and Freddy Sime, members SME, fillers and pigments.• Kaiwu Huang, Thomas Hilderbrand and Ricardo Santander members SME, of Virginia Tech, Thiele Kaolin and Carbo Ceramics, respectively, sorbents, filters and process aids.• Rhaghay Dubey and William Rapier, members SME, of Outotec and a consultant, respectively, specialty minerals.On behalf of ME readers, the editors thankTwo U.S. alumina refineries produced an estimated 1.5 Mt (1.65 million st) of alumina from imported bauxite in the United States in 2018. The 500-kt/a (550,000-stpy) refinery in Burnside, LA, owned by Almatis Inc. produced specialty alumina used in the abrasives, ceramics, chemical and refractory industries. The 1.2-Mt/a (1.32 million-stpy) refinery in Gramercy, LA, owned by Noranda Alumina LLC produced alumina mostly for use in aluminum smelters but also produced specialty alumina. An upgrade project at the Gramercy refinery to convert 200 kt/a (220,000 stpy) of capacity to produce more profitable specialty alumina was completed in the first half of 2018, and another project to increase capacity was started but a completion schedule was not available. The amount of new capacity was not disclosed, but it would be used to produce nonmetallurgical grade alumina. The 2.3-Mt/a (2.5 million-stpy) refinery in Point Comfort, TX, which was temporarily shut down in March 2016, remained closed throughout the year."

Jul 1, 2019

VOLUME I Volume I of this three-volume report is the result of development of a comprehensive, coordinated approach to site data-acquisition activities to produce key plans and reports during the evaluation and development of a surface coal mine. A logic diagram illustrates activities in the planning and decision-making process from exploration through post-mining monitoring. The report briefly discusses major elements, other than the site environment, which influence development of mining and reclamation plans and refers to other readily available literature for details outside the scope of this study. The essence of the rationale is shown to be the 1 employment of necessary skills at the proper time to evaluate specific data ' requirements and integrate them into a cost-effective program to produce initial and major feasibility reports, mining, and reclamation plans, and the environmental impact assessment.

Jan 1, 1976

By E. D. Gardner

Open-cut mining of copper ores in the western United States is a relatively new industry. At first the mining methods were mainly adapted from those used at open-cut iron mines and at quarries, but now efficient practices that are more suitable for the copper deposits have been developed. The pioneer in this field is the Utah Copper Co., of Bingham, Utah, which deserves great credit for working out much of the early procedure. Stripping began at that mine in 1906, and the large Garfield concentrator was put in commission in 1908. Next in order of development were the Nevada Consolidated Copper Co., at Ely, Nev. ; the Chino mine of the Ray Consolidated Copper Co., at Santa Rita, N. Mex. ; the New Cornelia Copper Co., at Ajo, Ariz. ; the Sacramento Hill mine of the Copper Queen Branch, Phelps Dodge Corporation, at Bisbee, Ariz.; and the open cut of the United Verde Copper Co., at Jerome, Ariz. The Sacramento Hill mine began to produce in 1923, and the United Verde open-cut mine has produced ore mainly in connection with stripping. The writer visited the Utah Copper mine in September, 1923; the Nevada Consolidated in August, 1923; the Chino in July, 1924; and the New Cornelia, the Sacramento Hill, and the United Verde open cut at various times during 1922, 1923, 1924, and 1925, mostly in connection with other work.

Jan 1, 1927

The papers contained herein summarize results of various recent Bureau of Mines investigations in the area of mine power distribution systems. They are based on information from Bureau personnel, contractors and grantees, and Mining Enforcement and Safety Administration. Conclusions drawn from a series of parameter measurements on mine power systems, taken over a 3-year span, are presented. Personnel and equipment hazards due to faults on isolated, solidly grounded, and resistance grounded three-phase systems are discussed. Two papers cover dc applications of circuit breakers, including a novel protection scheme for trolley lines. The methods of suppressing induced arcing currents and voltages in a-c machines are evaluated. An evaluation program for ground monitors is described. Acceptance test procedures and the importance of various paparameters for trailing cable splice are covered. A number of techniques for locating faults in trailing cables are described.

Jan 1, 1975

This Kaiser Engineers report on the feasibility of surface mining on the North Slope of Alaska has considered the quantity and quality of the North Slope deposits with attention paid to the economic, technical, and environmental constraints of the mining systems suggested for the three candidate minesites at Kukpowruk River, Elusive Creek, and Kuk River. Site selection, based on coal rank and quality as well as seam thickness and geometry, also considered demonstrated and hypothetical reserves relative to three mining systems (dragline, shovel, dragline and shovel), mining equipment requirements, infrastructure, and transportation relative to the Arctic environment and costed for potential markets. Throughout the report the delicate permafrost environment has received particular consideration. Recommendations based on the technical, economic, and environmental feasibility of mining the coal deposits of Northern Alaska by surface mining techniques have resulted in two conclusions: 1. The coal deposits can be mined with currently available technology; 2. It is uneconomic to mine these coals given current coal resource estimates, costs, and market conditions. A literature survey is included in appendix.

Jan 1, 1977

By R. Lusignea

A device has been developed for nondestructive testing the holding power of split tube friction rock supports. It operates by measuring the amount of decrease in internal volume when the support is forced into the drilled hole. The pullout force or slip load is a function of this decrease in volume. The device gives readouts of the average internal diameter and predicted pullout force or the support. Laboratory and field tests showed excellent repeatability and good correlation between predicted and actual pullout force. The device is hand-operated, lightweight (7.5 lb) and can be used on any friction support.

Jan 1, 1983

By W. H. Oppelt

The continuous gasification of lignite in an externally heated alloy-steel re-tort was investigated by the Bureau of Mines, Grand Forks, N. Dak., from 1945 to 1951. The main objective of the long-term experimental program was to obtain data on the mechanical performance of this type of gasification retort, particularly the alloy-steel heat-transfer surface of the retort, when operated on large pilot-plant scale. At the same time, extensive experimental data were obtained concerning the effect of process variables and the effect of a limited number of design modifications on gasifier performance. In the period covered by this progress report 4 pilot-plant runs totaling 2,879 hours of operation were completed with the rolled-plate, 310-alloy reaction tube. Over 30 million cubic feet of gas, having H2-CO ratios from 2.1 to 4.4, was made by the partial gasification of 636 tons of 1-1/2-by 3/8-inch natural lignite. Rates of gas generation were from 8,200 to 14,300 cubic feet per hour. Three of the four runs were carried out with the lowered gas offtake or continuous-annulus design modification of the gasification retort. In the final run of the series, gasification of lignite from seven different mines in North Dakota and Saskatchewan, Canada, was investigated at similar combustion-space temperatures and lignite and steam feed rates.

Jan 1, 1955

By R. F. Chaiken

The Bureau of Mines has conducted a study of mine fires in the Anthracite Region of Pennsylvania to determine the most effective approaches to fire control in this area. The problems involved in controlling an anthracite fire include the geological and mining conditions in this area, the propagation characteristics of anthracite, the fire control methods available, the hazards associated with these fires, and the mar-ginal effectiveness of past fire control projects. From this genecal background, fire control options were discussed as they apply in ISBO to the Centralia mine fire. Probable effectiveness, feasibility, and costs were assessedv The options evaluated include four excavation plans, flooding, hydraulic flushing, water curtain isolation, mining to construct an underground carrier, burnout control, and relocation of the community. The most advantageous from a technical viewpoint is an excavation method combining complete excavation of the fire zone within the borough with trenching to confine the remaining fire. It appears that for many anthracite fires, as for the Centralia mine fire, there are no available control measures that have a moderate cost, are proven effective, and produce minimal disruption on the surface.

Jan 1, 1983

By Terry J. Close

Between 1986 and 1989, at the request of the U. S. Bureau of Land Management, personnel from the U. S. Bureau of Mines Western Field Operations Center studied the highly-mineralized, 25,335-acre, Crack Canyon Wilderness Study Area (UT-060-028A), to evaluate its identified mineral resources. The 16-mi-long, 2-mi to 4-mi-wide stud/ area is on the southeast side of the San Rafael Swell, about 40 mi southwest of Green River, Emery County, southeast-central Utah. The study area is underlain by Mesozoic sedimentary beds. Uranium, the principle mineral resource, occurs in two formations. The principle uranium deposits are in mudstone, sandstone, and conglomerate lenses in the 22-mi-long outcrop of the Triassic Chinle Formation which parallels and straddles the northwest boundary of the study area, Some small low-grade uranium occurrences and an extensive gypsum deposit are hosted by the Jurassic-age rocks that underlie the southeast part of the study area.

Jan 1, 1989

By John B. Ivey

This is a geologic study of the U.S. Bureau of Mines Oil Shale Tract in the Piceance Creek Basin of Rio Blanco County, Colorado for the preparation of a set of detailed surface geologic maps, measurement and identification of joint attitudes and frequencies, and the classification and mapping of the soils of the area.

Jan 1, 1978

By Robert L. Lagace

A prototype adaptive volume control for the loudspeaker output of mine trolley carrier phones was designed, built, and tested in the laboratory and in a mine. This volume control senses, and adapts to, the ambient acoustic noise environment in such a way as to produce a loud sound output under noisy conditions, and a quieter output under quiet conditions, thereby producing an understandable and unstartling volume level under all noise conditions. The design approach, prototype hardware, and test results are described, and the device is shown to be feasible for in-mine operations. The circuit design principles are easily applicable to currently available mina trolley carrier phones. Recommendations for practical improvements are included. An in-mine experiment to assess the practical feasibility and utility of the dedicated wire technique for overcoming poor trolley carrier phone system performance was designed, performed, and evaluated. The technique involves the use of a single, low-loss, properly terminated auxiliary wire, placed in the rail haulageway, which allows signals to naturally couple to and from the trolley wire/rail transmission line, and thereby significantly decrease the overall signal attenuation rate on the trolley wire/rail line. The in-mine dedicated wire experiment, results, and conclusions are described, and the technique is shown to be a valid and practical one for significantly Improving carrier phone system performance in mines. Guidelines for the installation and use of the dedicated wire are provided. Recommendations are made for obtaining further practical information on its performance and utility. A second in-mine experiment to assess the feasibility and utility of the low-impedance (low-Z) line technique for overcoming poor carrier phone signal transmission in mines was designed, performed and evaluated. The low-Z line technique involves the periodic connection of shunt capacitors between the trolley wire and the rail to artificially lower the line characteristic impedance. This causes the low impedance shunt loads encountered across the trolley wire/rail line to be less mismatched to the line, thereby reducing the overall attenuation of carrier phone signals. The results of in-mine experiments performed along unenergized and fully operational sections of trolley wire/rail line are described. The experiments were designed to measure line parameter such as inductance and capacitance per unit length, characteristic impedance, and propagation phase velocity, in addition to signal strength versus distance behavior under normal and low-Z line conditions. The low-Z line technique is shown to be valid, but not as practical as the dedicated wire technique which is recommended as the most favorable for most coal mine applications.

Jan 1, 1979

By J. R. Thoenen

Up to 1914 almost all of the world's supply of potash came from Germany and Alsace. With the cessation of shipments from Germany during the World War the importance of a domestic supply was evident, During the past 15 years the United States has been working toward the establishment of a domestic potash industry which would end foreign dominance in this commodity. The Federal government has taken an active part in this program. As its share in the work, the Bureau of Mines has ascertained the potash resources in certain districts through core drilling and has engaged in a comprehensive program of research on the extraction of potash from its various minerals. Until the passage of the Winter bill (H. R. 496) by Congress in 1928 the Bureau of Mines had not been able to give any consideration to the western ores, wyomingite (leucite) and alunite. With the Passage of this bill, however, the ray was opened for the extension of the potash studies to cover these materials.

Jan 1, 1932

By Grant R. Brown

The report provides guidance for determining those environmental impacts associated with the surface mining of steeply pitching coal seams. In addition to the environmental impacts, four additional issues are addressed, namely (1) Time and motion studies of those coal mining systems employed in mining seams which pitch in excess of 25°, (2) Assessment of those mining techniques, (3) Development of rationale for the mining methods employed, (4) Identification of the reclamation practices and determine whether these practices were in compliance with appropriate Federal and State regulations. Five surface mines located in three geologically distinct basins of the United States were analyzed during the period of August through November 1979. The three basins include the Hanna Basin of Wyoming, the North Park Basin of Colorado and the Southern Anthracite Field of Pennsylvania.

Jan 1, 1980

By J. W. Thompson

RAILROAD GRANT-MDIERALS. Diatomaceous or infusorial earth when found in such quantity and quality as to render lands containing deposits valuable therefor are mineral lands within the meaning of the mining laws and must be excepted from grants to the Central Pacific Railway Company. Central Pacific Ry. Co., In re, 45 Land Decisions, 223, p. 226. RAILROAD GRANT-CLASSIFICATION, If any evidence of minerals is found upon lands within a railroad grant and the showing is sufficient in the opinion of prudent and qualified persons to warrant further exploration and expenditure, with reasonable prospects of success, then the land can not be classified as nonmineral and is not subject to the grant to a railroad company. But where there is no present indication of minerals nor any geological evidence upon which to base a mineral finding, land should not be classified as mineral, or held for further classification and reserved from the railroad's grant, upon the surmise that future prospects might disclose evidences of minerals. Southern PacUl.c Ry. Co., In re, 45 Land Decisions, 326, p. 329. INDEMNITY SELECTION BY RAILWAY COMPANY, Under section 3 of the act of July 2, 1864 (13 Stat., 365), and the joint resolution of May 31, 1870 (16 Stat., 378), the Northern Pacific Railway Company could take coal and iron land within its primary or grant limits. It could not base an indemnity selection upon the claim that certain land was coal or iron in ;;haracter, as such land was not lost to it as part of the grant. But the company was authorized to select other lands in lieu of those lost because of their mineral character, but the word "mineral" did not include iron or coal, and, accordingly, the railroad company was entitled to take coal lands under its indemnity selection.

Jan 1, 1917

By R. O. Neal, G. St. J. PERROIT

As natural gas is a waning resource in many places, increased interest has attached to the use of gas for the manufacture of carbon black. Because of a large number of requests for information on the subject, the Bureau of Mines has undertaken a detailed study of the carbon-black industry, covering the mechanical details of commercial methods, with the purpose of increasing the recovery of carbon black by such processes. A study has been undertaken of the economic factors governing the carbon-black industry, the uses and properties of carbon black, the dE)velopment of more Itccurate methods of testing carbon black, microscopic examination of different grades of black, physicochemical study of methods' of mQ.nufacture now in use, and research on new methods of manufacture. Part I of this paper covers the engineering and economic side of the industry; the other phases of the investigation which have been under the direction of G. St. J. Perrott, of the Pittsburgh station.of the United States Bureau of Mines, are discussed in Part II.

Jan 1, 1922

By Ernest E. Fairbanks

[Microscopic methods have proved to be valuable assets in the study of low-grade ores. While the chemical assay u a ally discloses tine total content of valuable metals in such an ore, a thorough knowledge of the nature of the ore should form the from which to prepare an efficient means of recovery. In the treatment of low-grade ores, inefficient recovery, as indicated bay the amount of valuable mineral permitted to go to waste in the tailings, is too frequently the rule rather than the exception, As methods of recovery become more efficient, many low-grade 10 mineral A posits suddenly assume o commercial significance, In much of this material the minerals are so finely disseminated and intermixed that identification even by microscopic methods is a difficult matter. The application of microchemical qualitative analysis with the aid of new device described in this paper, will solve many of the problems of identification encountered in the study of low-grade potential ores. In these ores, especially, the limitations of ordinary microscopic methods are liable to become very great. The microchemical tests obtained by applying a standard set of reagents to a polished knoting whether or not a tarnishing action develops, have considerable value but arc far from being infallible. It is well-known that electrolytic effects are apt to affect seriously the diagnostic value of the tests, end this effect is encountered much more frequently in dealing with finely desseminated minerals. resort to microchemical qualitative analysis, therefore, becomes indispensable.]

Jan 1, 1924

By F. Fraas

ELECTROSTATIC methods are used to separate and concentrate or purify granular particles derived from ores or various synthetic and agricultural products. Compared with other separation methods that require many technological refinements, the electrostatic attraction of fibers, grass, and seeds to charged surfaces clan be accomplished under the most primitive circumstances, and the early development of this method of beneficiation seemed very promising. Precise application of the method to provide high selectivity, however, is a complex procedure, and interest in this method declined. During this period Mr. O. C. Ralston initiated a Bureau of Mines research program oil electrostatic separation. It is the purpose of thins publication to describe the development of the electrostatic method of particle separation from the early beginning to the present resurgence of interest. Most of the information for this description bas been derived from references, a few of which were not available for thorough review. Much information has been drawn from the investitions of the Bureau. Acknowledgments Mr. O. C. Ralston, former Chief metallurgist of the Bureau of Mines, began the research program on the subject and did research on the mils literature. Both Mr. Ralston and Mr. H. B. Johnson, former president of the Huff Electrostatic Separator Co., furnished patent references. A critical review by Mr. F. D. Lamb, Research director, and Mr. M. J. Spendlove, Supervisory metallurgist, Bureau of Mines, College Park Metallurgy Research Center, lifts been of much value in preparing this report.

Jan 1, 1962

By F. M. Lewis, J. F. Myers

W. I. Garms-—The authors state that when they added 11 tons of balls to the 45 pct volume ball load, the power needle did not budge. The question arises as to whether any increase in capacity accompanied the 11-ton addition. It is hardly conceivable that all of the balls making up the 11-ton addition were sterile. However, as the work done in the ball mill is not by kilo-watthours per se or balls per se but by kilowatthour-balls, it is possible that the kilowatthourballs in the mill before the 11-ton addition had a different amperage, voltage or robustage than those in the mill after the addition and that the overall outcome was that equal work was done before and after the addition. The authors can keep the efficiency that they got with the 45 pct volume 1-in. ball charge and get additional capacity by putting more kilowatthourballs to work in the form of the addition of 11 tons of 2-in. balls to the present ball charge, and subsequent makeup additions by weight of 20 pct 2-in. balls and 80 pct 1-in. balls. J. F. Myers (authors' reply)-—Mr. Garms points his finger at the 11 tons of "sterile" balls added to the Tri-cone mill. A fact so interesting to us that we felt it should be reported. Clearly, ball slippage at the existing mill speed prevented any further transfer of power from the shell to the ball mass. We agree that the kilowatthourballs would increase, were we charging rough 2-in. balls as suggested by Mr. Garms. The assumption is, of course, that we would get a corresponding increase in work done. Our reported data (CIME meeting, Vancouver, 1946) shows a gain of work accomplished of 7.6 pct as we decreased the ball size from 2 in. to 11/2 in. and a further gain of work accomplished of 2.1 pct when we went from 11/2 in. to 1 in. The small ball results reported by H. R. Banks at Chapman Camp are also very convincing. In the case of 2-in. balls they would take the conventional ball path and start cascading. They would thus destroy the classifying pool over the "foot" of the

Jan 1, 1951

By S. A. Falconer

D. A. Dahlstrom—Mr. Falconer has done an admirable job of proving the adaptability of the cyclone to the beneficiation of a very difficult size range in the preparation of coal. The addition of the cyclone to other coarser size methods makes it economically feasible for the coal operator to rigorously control his marketed products at a high and uniform quality level down to the 48 and 100-mesh size. Furthermore, it should be pointed out that by utilizing the cyclone as a deslimer or classifier the —3 200-mesh fraction, usually containing large percentages of undesirable material, can also be quickly and cheaply removed from the clean coal. Advantages of such a step are several: (1) Reduction of ash content, especially where clays and slimes are serious. (2) lower moisture content of the final coal. (3) easier mechanical and thermal de-watering of the fine coal due to higher cake and bed permeabilities. The author has indicated that adjustable control means should be installed on the cyclone operating on a heavy-media slurry. This also holds true for the cyclone acting as classifier, deslimer or preliminary dewatering agent and is worthy of special emphasis. Such controls, while not necessarily automatic, must be simple, rapidly adjustable, and require a minimum of attention. Three methods available to the operator are (1) throttling valve on the feed line, (2) back pressure valve on the overflow, and (3) adjustable diameter underflow nozzles. The first two, while fulfilling the specifications, suffer the disadvantage of restricting capacity if severe throttling is necessary. The third method has little effect on capacity and easily maintains an underflow of correct moisture content. Several designs are possible, but two find the widest application. The first was developed by Robert Piros of The Truax-Traer Coal Co. and uses a simple casting containing two holders for underflow nozzles which can be rotated about an axis parallel to the cyclone centerline. These holders retain the underflow nozzle flush with the conical section walls. When a change in nozzle diameter is required, the new size is placed in the spare holder and rotated into place. A second design utilizes a soft rubber cylindrical tube which is compressed or released from three sides, causing the inner diameter of the tube to decrease or increase. This is achieved by using a machine-threaded,

Jan 1, 1951