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By Lucia Kuizon

The Cactus Springs Roadless Area Review and Evaluation (RARE II) study area (No. A5188) comprises 12,800 net acres (5,180 ha) in San Bernardino National Forest in west central Riverside County, California, about 20 air miles (32 km) southeast of Palm Springs. Mineral investigations are made by the U.S. Bureau of Mines on National Forest lands identified as Further Planning Areas in the RARE II program. The Bureau of Mines reviewed literature, mining claim records, and production files; examined the study area; and mapped and sampled mineral properties where appropriate.

Jan 1, 1983

By Graham W. Marks

Recently it was shown the total energy method of spectrochemical analysis is suitable for the quantitative estimation of many of the elements of which ores are composed. It was shown how this method can be applied to the determination of germanium, tin, and lead. Continuing, this work, the present report deals with analyses for beryllium, zinc, cadmium; and indium. There are three basic problems in these investigations. The first is to study the influence of those elements that make up the greater part of an ore sample on the spectral-line intensities of the elements for which analyses are being made, the latter generally being the minor constituents. The second is to develop proper methods for the preparation of standard spectrographic curves. Finally, we are concerned with improvement in equipment and procedure, so that greater accuracy can be achieved. As discussed previously, it is better to study as groups those elements that belong to the same group in the periodic table because their spectra are similar. Beryllium, zinc, and cadmium are thus related. Indium was included in this work because it is, associated with zinc and cadmium in zinc ores.

Jan 1, 1948

By Albert W. Deurbrouck

The preparation characteristics of the coals of Buchanan County, Va., are described in this Bureau of Mines report. Twenty-one samples ,,,ere collected from 9 coalbeds in the county. Of these samples 13 were of metallurgical quality as received, and 8 required some upgrading to provide acceptable products. In general, the coals were of low to medium ash and sulfur content, and ranked as medium-to high-volatile bituminous. In 1963, production in the county was in excess of 13 million tons, of which 2.2 million tons were mechanically cleaned.

Jan 1, 1966

Remarks of Mr. Robert W. Hunt, General, Superintendent, Albany and Rensselaer Iron and Steel Company., Troy N. Y.—In discussing Dr. Dudley's two most interesting papers, I feel a natural hesitancy in disagreeing with conclusions formed after such careful and conscientious work. But I think he has made his deductions from too meagre premises. The analyses of but twenty-five samples are entirely too few to justify the establishment of so important a formula. When we consider that he indirectly proposes to regulate an interest amounting, even at the present low prices, to over $20,000,000 per annum, we may well hesitate before accepting a formula based upon the chemical and physical analyses of but twenty-five steel rails. Dr. Dudley touches the keynote in referring to the proposed labors of the Government Test Commission. They based their hopes of attaining success upon the chemical and physical analyses of a very large number of samples, and in the only branch of investigation which the short-sighted policy of Congress has allowed them to complete, i.e., chain cables, we find that a dozen, twenty-five or one hundred tests gave no satisfactory results. It was only after many hundreds that they were enabled to' draw conclusions. There are so many circumstances hearing upon the life of a rail, that the task of extracting a correct result seems herculean. I presume I am right in stating that in our Northern latitudes early winter and spring months witness the breaking of the greatest number of rails, thus seeming to prove that an unstable road-bed has much to answer for. Then, again, broken and flattened wheels must be taken into account, but I am convinced that more rails have been broken by the treatment which they received before leaving the rolling-mill

Jan 1, 1879

By Robert D. Saltsman

Two modes of seal application were identified, and promising state-of-the-art seals of both types -shaft and drum -were selected for initial rating by non-destructive testing. Only one shaft seal survived the initial test, and a search was made for other candidate seals including new seals. One new type of seal was found that gave promising enough operation, as both a shaft and drum seal, to be recommended for installation in prototype wet-head machines.

Jan 1, 1975

By Terry J. Close

A mineral resource survey of the 236-mil (611-km2) Hyalite-Porcupine-Buffalo Horn wilderness study area (RARE 11 Areas No. 1-155 G, Gallatin Divide; and H, Hyalite) between the Gallatin and Yellowstone rivers in Montana, indicates there are phosphate rock and petrified wood resources (fig. 1). The area also has some potential for oil, gas, and geothermal resources. Stone and alluvium are abundant but appear to have little potential for development because other sources are available nearer to markets.

Jan 1, 1981

By L. G. Marshall

This report is one of a series published by the Federal Bureau of Mines, describing mining methods and performance at individual mining operations throughout the United States. The objective of these papers is to promote development and conservation of our mineral resources by disseminating reliable technological information on mining methods, practices, and performance. Limestone deposits in Iowa are extensive and reserves are large. Most of the past production came from the eastern third of the state, although over half of the counties in the state have produced, or are now producing limestone. The stone is used as aggregate, road metal, agricultural lime, riprap, fluxing stone, railroad ballast, and in the manufacture of cement and lime.

Jan 1, 1962

By George A. Savanick

Coal mine roof shales fracture preferentially at slickensided surfaces because of weak or nonexistent adhesion between two slickensided rock surfaces. The purpose of this Bureau of Mines research was to characterize chemically the thin film of smooth, glossy material that makes up the slickenside. This material was analyzed by electron spectroscopy and ion scattering spectrometry while in place on the rock surface and by standard methods of quantitative chemical analysis on concentrate removed from the rock. These analyses showed that the chemistry and mineralogy of the slickensides are similar to that of the adjacent shale.

Jan 1, 1974

By R. S. Dean

T HE theory of hardening by heat treatment was, as usual, the most actively discussed phase of metal working theory and in spite of the fact that it is now ten years since the dispersion theory was proposed by Messrs. Merica, Waltenberg, and Scott, it still retains a dominating influence. It is being increasingly recognized. however, that in its simplest form, that is, the purely mechanical effect of very fine crystallites distributed through a groundmass, it is distinctly in- adequate. To explain the observed facts we are obliged to assume some well-defined intermediate stage between supercooled solid solution and conglomerate, however fine be the particles of the latter. This intermediate has been inferred by Gaylor and Preston to be "the rejection of the atoms of the dissolved metal from the lattice of the solid solution accompanied by the possible formation of molecules."' Perhaps this may well be designated as the formation of supersaturated solid solution. Some very definite evidence of such an inter- mediate stage has been found in the hardening of steel where it appears that the very hard martensite may be considered as a supersaturated solution of carbon in a iron. The X-ray spectrometry of drastically quenched steel shows a tetragonal lattice whose parameter changes by tempering at 100" until it coincides with the cubic lattice of iron.? The same gradual change of the tetragonal to the cubic lattice has been observed by Sekito when esamining layers on increasing depth below the surface of a quenched carbon steel.

Jan 1, 1930

By Y. Lahaye, O. Martinsson, B. I. Palsson

"Four main and three minor rare-earth-element (REE)-bearing minerals were identified and quantified in the Kiirunavaara apatite iron ore tailings using optical microscopy, an electron probe microanalyzer (EPMA) and a mineral liberation analyzer, and their chemical compositions were analyzed by the EPMA and laser ablation inductively coupled plasmamass spectrometry. REEs are shown to be contained in the minerals apatite, monazite, allanite, titanite, zircon, thorite and synchysite. In zircon, thorite and synchysite, they occurred in only trace amounts and contributed limited amounts to the total REE budget, and these are consequently of minor importance. Monazite occurred as inclusions in apatite and as free particles, 90 percent liberated. Allanite occurred to some degree in mixed grains with magnetite but also as free particles. Monazite mainly reported to the apatite concentrate, while allanite and titanite largely went to the tailings, the latter preferably to those fractions smaller than 38 µm. The amount of titanite in the finest tailings fraction was 2.3 weight percent, containing close to 1 percent REEs, with heavy rare earth elements (HREEs) making up 28 percent of the total REEs. However, a texturally distinct group of titanite grains showed an HREE/REE ratio of up to 67 percent. Furthermore, titanum dioxide analyses indicate that titanite is preferentially released into the tailings from the secondary magnetic separation step in the concentrator. Our data therefore suggest that titanite, occasionally enriched in HREEs, can be extracted from the processing stream and might thus be considered a new source for REEs at Kiirunavaara and similar deposits.IntroductionDeposits of apatite iron ores are the major source for iron in the European Union and are exploited by Luossavaara-Kiirunavaara AB (LKAB) in several mines in the Kiruna-Malmberget area in northern Sweden. Kiirunavaara is the largest of the apatite iron orebodies in Sweden, comprising more than 2 Gt of iron ore with 60 to 68 percent iron (Fe). At the end of 2015, the total accumulated production of crude ore from openpit and underground mining since the start of mining was 1,566 Mt, with ore reserves of 644 Mt grading 46.3 percent Fe (LKAB, 2016). The deposit defines a steeply dipping tabular body, approximately 6 km long and up to 180 m thick, extending at least 1,500 m below the surface. It is situated in the middle part of the Palaeoproterozoic Kiirunavaara Group of volcanic rocks and follows the contact between a thick pile of trachyandesitic lava and overlying pyroclastics (Martinsson, 2004)."

Jan 1, 2017

By James L. Eirls

Tracor MBA under a contract to U.S. DOI Bureau of Mines designed, developed, fabricated and demonstrated a conveyor belt service machine. It is self-contained, battery powered, rubber tired and capable of handling, storing and transporting conveyor belting, wire rope and associated structures for sectional conveyor belts. While moving the tail section to its next position the machine discharges the belting, wire rope and belt structures. The belting is elevated and separated to provide for the insertion of the structures with minimum expended effort. A hydraulic system provides the power for steering, braking, winding or unwinding under controlled tension the belting and wire rope, operating a load-bed slat conveyor, raising, lowering and locking connection hitches and powering external hydraulic tools. Also, a pneumatic system is available to operate air impact tools. The service machine, with its present components can function in coal seams as thin as 48 inches, double wind conveyor belting 42 inches wide, 400 feet long, load or unload 3/4" wire rope on two separate reels and is controlled by two operators. A complete belt move using this machine requires only four workers. Successful underground demonstrations were conducted in coal mines located in West Virginia and Kentucky.

Jan 1, 1983

By J. Harrison Daniel

Were the legislators and politicians responsible for the closing of the U.S. Department of the Interior?s Bureau of Mines (Bureau) in March 1996 fully aware of what they were doing? Throughout the United States? history, the domestic mining and minerals industry has been largely responsible for the nation?s growth and prosperity that had made it a world leader. The mining and minerals industry made it possible for the young nation to catch up with Europe during the Industrial Revolution, played an essential role leading to victories in World Wars I and II and was a core ingredient for continued economic growth. For a number of decades, America?s import dependency on non-fuel mineral materials has continued to increase. (USGS Mineral Commodity Summaries). Developing domestic resources to meet current and future demands ? particularly those resources considered to be of strategic and critical value to national security ? is necessary. Federal involvement is required since many of these resources are located on public lands. Another reason for federal involvement is that the success of the industry depends on long-range research programs and advances that may take up to 25 years to become commercially available. This situation requires federal partnership to coordinate the programs necessary to collectively involve the industry, individual mining companies and colleges and universities. So, how was it possible to close a federal agency that had contributed so much to the nation?s welfare in a mandated 90-day period, with more than 1,200 employees losing their jobs?

Jan 4, 2010

By Seth T. Reese

REPORTS received from operating companies by the Bureau of Mines, United States Department of the Interior, indicated marked progress in the reduction of injuries to employees in the coking industry in 1951 as compared with 1950. The fatality rate (0.14) per million man-hours of exposure declined 33 percent and was the second best performance since statistics on the industry were first collected in 1916. The nonfatal-injury rate (10.94), the best since 1940, declined 8 percent and was bettered only in 8 of the past 36 years. The nonfatal rate is based on all injuries resulting in loss of time for more than the remainder of the day on which the injury occurred. The exposure to hazard, as represented by the number of man-hours of work time during the year, was 7 percent higher than in 1950 and, except for the year 1943, was the highest since 1920. The fatality rate for men employed at beehive-coke ovens decreased 16 percent and the nonfatal-injury rate 23 percent, while the man-hours of work time or exposure increased slightly over 16 percent. The fatality and nonfatal-injury rates at byproduct ovens declined 33 and 2 ½ percent, respectively, while the number of man-hours worked increased 6 percent.

Jan 1, 1954

The Nena high sulphidation-type copper-gold deposit is composed of andesitic pyroclastic units with minor interstratified lava flows. Epiclastic sandstone and conglomerate, and siliciclastic rocks consisting of mudstone, shale, lithic and bioclastic sandstone and conglomerate are locally present. Pre-mineral diorite intruded and domed the volcano-siliciclastic sequence. Economic copper-gold is hosted by vuggy quartz altered lapilli tuff and tuff breccia. The early hydrothermal alteration stage involved deposition of epithermal banded quartz and chalcedonic silica in localised environments. This alteration stage was locally superimposed by a hydrothermal breccia event. Following the breccia event, magmatically-derived volatiles were channelled through a NW striking dilational fault zone and generated the high sulphidation alteration. The high sulphidation alteration is zoned from a vuggy quartz core with local massive replacement silica through a broad pyritic quartz-alunite halo and finally to a thin illite-smectite zone. This is surrounded by regional chlorite-epidote-smectite alteration. A gangue mineral phase consisting of quartz, alunite and baryte overprinted the zoned high sulphidation alteration and preceded the main copper-gold-arsenic mineralisation. Early sulphide deposition is characterised by marcasite, arsenical pyrite and melnicovenite. Main-stage copper-gold mineralisation involved sequential deposition of hypogene bladed covellite+chalcocite, enargite-luzonite and luzonite+stibioluzonite respectively. The copper sulphides are zoned from bladed covellite-chalcocite in the north (cross-sections 5000 - 5600 N) through enargite-luzonite (cross-sections 4700 - 5000 N) and to luzonite????stibioluzonite in the south (cross-sections 4400 - 4700 N). A late phase of minor acicular covellite and enargite+luzonite overprinted the zoned copper sulphides and associated gold mineralisation. Gold mineralisation commenced at the transition from enargite to luzonite, and continued through the deposition of luzonite-stibioluzonite in both stages. Most gold was deposited during the main-stage mineralisation. Yellow native sulphur was deposited in the remaining vugs and defines the waning stage of the hydrothermal system. Post-mineral dioritic intrusives and feldspar porphyries intruded the volcano-siliciclastic sequence. Finally, supergene chemical processes with associated erosion and uplift generated a 40 - 50 m thick oxide-hosted gold cap. The oxide gold cap is underlain by a 35 - 45 m thick blanket of supergene chalcocite+covellite mineralisation which overlies and occurs throughout the main hypogene copper-gold zone. Supergene gold is related to the distribution of primary gold-bearing sulphides. Therefore, remobilisation and redeposition of gold are considered to be insignificant and very localised.

Jan 1, 1999

By AIME AIME

PLANS are now well advanced for the joint meeting of the Institute and over a dozen other engineering societies in Chicago during the week beginning June 26: Engineers' Week at A Century of Progress. All engineers planning to visit the Fair will find it to their advantage to be present at this time so far as the Chicago attractions are concerned, and Eastern members will also have the advantage of special transportation arrangements on June 24 and 25. The tentative program is given at the bottom of the next page. Monday morning, June 26, will be reserved for registration of members and guests and the Woman's Auxiliary at the Stevens Hotel, where special rooms will be provided. A luncheon will also be served there, and in the afternoon, a technical session on nonmetallics. Instead of having the big family dinner that evening at the Stevens, as at first proposed, the local committee has planned to have it at the Fair Grounds, where special facilities have been arranged. A meeting of the Board of Directors and a few invited guests will precede the dinner. All members and guests are likely to be interested in visiting the Museum of Science and Industry, so that will be the sole event on the program for Tuesday morning, June 27. The big attraction there at present is the model coal mine, the first operative coal mine ever built for exhibit purposes. It is based on the Deutsches Museum mine at Munich, but goes far beyond that in realism, and takes the visitor on an extended tour underground. It shows him in half an hour more types of modern mining machinery and coal geology than he would be likely to see in a week's underground study in the coal fields. The Institute members will be the first group to go through this mine.

Jan 1, 1933

By R. R. Tatiya

Data obtained from a copper mine were used in a comparative study of the reserve estimates generated by applying geostatistical methods to surface borehole data, underground core drilling results and assay values from chip sampling. Global estimation of the deposit performed by kriging of the low-density sampling data from the surface boreholes did not provide reliable results, but could identify the potentially mineralised zones. The reserve generated from core drilling results correlated well with that estimated from chip sample data and with that estimated by the conventional methods used at the mine. A satisfactory reserve evaluation could, therefore, be obtained by kriging of the data from the underground core drilling alone, provided that a systematic sampling procedure was adopted. Estimates based on chip sampling information could be used as a check, which could avoid the current practice of chip sampling of most of the mine workings. The aim should be to develop a semi-variogram for the deposit, which could be used to estimate the reserves by kriging

Jun 19, 1905

A preliminary study was conducted by the Bureau of Mines to determine the effect of humidity on salt mine airborne dust levels. Results showed less dust where the humidity was elevated. Dust reductions appeared to be dependent on the equilibrium between humidity and salt.

Jan 1, 1980

By C. Lurie

This final report describes the work performed by Gulton Battery Corporation under USBM Contract No. HO-112033, entitled "Research and Development on Lithium-Nickel Fluoride Batteries For Mint Life Support Equipment". The lithium-nickel fluoride couple was chosen For this investigation because of its high theoretical energy density (626 Wh/lb), its ability to operate at ambient temperatures and the fact that it showed promise as a secondary system. The theoretical energy density of the lithium-nickel fluoride couple is ten times greater than that of the widely used lead-acid battery and three times greater than the silver-zinc battery which has the highest theoretical energy density of the commercially available secondary systems. The experimental program first evaluated the cell components individually. The results of these studies then formed the basis for investigations of cell performance using experimental three-plate cells. These cells consisted of one nickel-fluoride and two lithium electrodes. All work was performed in a glove box under an argon atmosphere which was sufficiently pure to maintain the shiny appearance on freshly prepared lithium surfaces. The major portion of the work effort was concerned with the nickel fluoride electrode. Binder, conductive diluent, fabrication technique, as well as the nickel fluoride active material itself, were considered. Criteria for binder materials were established and six classes of materials encompassing thirteen binders were evaluated. The candidate materials were initially screened for appropriate chemical and physical properties and finally evaluated in three.-plate cells, Two epoxy powders emerged as the most promising binders. Two types of conductive diluent were evaluated. The first is a carbon black of low bulk density and high surface area. This material is a good conductive diluent; however, electrodes fabricated with it lacked good mechanical strength. It was hypothesized that a uni¬form, small particle size, low specific surface area would improve the mechanical properties of the electrodes. Therefore, two samples of graphicic materials, milled to uniform powders in the one-to-ten micron range were evaluated. Electrodes prepared with the graphitic materials had superior mechanical properties, However, their electrical performance was significantly poorer and voltage losses of 0.2 to 0.3 volts were observed. Several electrolyte solutions were evaluated. N-Methyl-2-Pyrrolidone was tested but found to be incompatible in the presence of lithium. Lithium perchlorate, lithium hexafluoroarsenate, and lithium bromide were tested as two-component electrolytes in propylene carbonate solvent and their performance compared with that of the single electrolyte solutions, Lithium perchlorate gave the best performance. Lithium hexafluoroarsenate was also evaluated in methyl formate and appears to give equivalent performance. The lithium perchlorate-propylene carbonate system is preferred as it is easier to handle and less expensive.

Jan 1, 1973

THE purpose of this chapter is to present a general outline of the basic open-hearth process for the benefit of students, practicing open-hearth operators, and metallurgists who wish to review the subject. The discussion is limited to a description of the sequence and purpose of the operations, illustrated by data and examples. Subsequent chapters deal with more detailed and fundamental studies of the subject. The function of the basic open-hearth furnace is to convert various types of ferrous material into finished steel of given com- position and quality. In comparison with other steelmaking methods, the basic open-hearth process is one of the most versa- tile, both from the standpoint of the raw materials that can be used and the types of steel that can be produced. The process can be considered as a sequence involving melting, refining, and deoxidation. With some types of liquid-metal charges, the melting stage is not present, but refining and deoxidation in varying degrees are fundamental features of the process. GENERAL DISCUSSION OF BASIC OPEN-HEARTH PROCESS The first consideration in open-hearth practice is the type of charge on which the operation is based. This consists of three components-fluxing, oxidizing, and metallic materials. Fluxes. In the basic process the fluxing material is primarily lime, added in the form of either limestone (CaC03) or burnt lime (CaO) . This is supplemented by magnesia (MgO) and lime from the furnace bottom and banks. The function of these fluxes is to form a slag with the silica (SiO2) , manganese oxide (MnO), iron oxides (FeO and Fe203), and phosphorus oxide (P205) that are produced by the oxidation of varying amounts of the silicon, manganese, iron, and phosphorus in the charge during melting and refining. The slag, composed of the basic fluxes and the neutral and acid oxides, floats on top of the steel bath when the charge is melted. The composition of this slag depends on the amount of each slag-forming element present in the charge and on the extent of oxidation of these elements during the course

Jan 1, 1964

By Richard S. Gaps

In 1983 the U.S. Bureau of Mines conducted a mineral survey of the Golden Valley Wilderness Study Area (WSA), CDCA-170. The 29,887 acre WSA, located in the western Mojave Desert near Ridgecrest, California, is underlain by pre-Tertiary plutonic rocks and volcanic and sedimentary rocks ranging in age from Miocene (?) or Lower Pliocene (?) through Pleistocene and Recent. No mines were operating in the WSA in 1983, nor is any mineral production known to have come from the WSA. Two mining claim blocks, portions of which are within the WSA, and seven isolated prospects, four inside the USA, were examined and sampled. No mineral resources were identified. Widespread propylitic alteration, with localized argillic and alunitic alteration, occurs along the southern boundary of the study area. Samples from claims and prospects within the altered zones are anomalous in gold, silver and arsenic, and some contain antimony, tungsten and mercury, indicating gold resources may exist. Alluvial sample results suggest recent claims in the northwest corner of the study area may also have gold resources. Portions of the study area are within the Randsburg Known Geothermal Resource Area while other segments are considered prospectively valuable for oil and gas and for sodium.

Jan 1, 1985