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By Kenneth E. Hay

The Bureau of Mines collected coal and coal waste aggregate material from two different mine sites to determine their strength characteristics for use in concrete. The concrete would be placed underground as support walls for ground control in adverse conditions or unique mining applications. A standard mix design was established for a "wet" mix using a water-to-cement (w/c) ratio of 1.0 to facilitate pumping into place. Later, material was collected from four more mine sites and used to make 2-by 2-by 2-ft test blocks with the same w/c ratio. A pull-out cone device and borehole shear tester were used to determine the in situ material strength of the test blocks. These techniques will provide a simple and quick way of determining support wall strength in an underground environment. Test results from the pullout cone de-vice showed a good correlation of 0.98 to test cylinder compressive strengths of the same mix. Results of the borehole shear tester were inconclusive.

Jan 1, 1986

By G. T. Fisher

The material requirements of carbide cutting tools for machining steel and cast iron are dependent on WC bonded with Co, with additions of TaCand TiC. The Bureau of Mines is conducting research to devise substi-tute materials, based on Ni-alloy-bonded TiC, for C-5-grade cutting tool applications. This substitution would result in less dependence on foreign sources for Co, Ta, and W, and use of lower cost materials. In this preliminary study, the Bureau investigated the effects of composition and processing variables on the transverse rupture strength and hardness of Ni-alloy-bonded TiC to identify compositions that exhibit promising mechanical properties. Further systematic modification of these compositions by soild-solution strengthening additions would subsequently be evaluated to obtain cutting tool materials with requisite properties and performance for C-5 applications. Compositions for evaluation were prepared by a powder metallurgy method of cold-pressing and liquid-phase sintering. Complementary analysis of compositions included chemical analysis, X-ray diffraction, energy-dispersive X-ray spectro-scopy, and density measurements. Based on results of this investigation, promising compositions were determined to be 59.37TiC-25Ni-5Mo-lO.63Mo2C, 59.68TiC-25Ni-3.33Mo-1.77Mo2C-6.67W-3.55WC, and 59.35TiC-25Ni-l.67Mo-3.54Mo2C-3.33W-7.1WC.

Jan 1, 1987

By W. J. Wenger

THIRTY-FOUR analyses of crude oils from the fields of the Four Corners Area of Arizona, Colorado, New Mexico, and Utah are presented and compared. The samples, taken from formations in four geological time periods, have high gravity and low-sulfur, -nitrogen, and -asphalt content. Generally, the oils are paraffinic in the low-boiling fractions, with increasing naphthenicity in the higher-boiling fractions. Oils from Cretaceous formations resemble other Cretaceous oils in the Rocky Mountains, but oils from Permian and Pennsylvania formations are unlike other oils of these ages in the Rooky Mountains. The differences in the oils are minor and cannot be used to distinguish between fields or between producing formations. With minimum special processing, the oils should yield large amounts of good-quality motor fuels. INTRODUCTION The only place in the United States where four States have a common junction is known as the Four Corners Area. This area (fig. 1) includes the northeast corner of Arizona, the southwest corner of Colorado, the northwest corner of New Mexico, and the southeast corner of Utah. It includes three major geological basins: The Black Mesa, the San Juan, and the Paradox. Major oil developments have occurred in both the San Juan and Paradox basins, but no discovery of commercial importance has been made in the Black Mesa basin.

Jan 1, 1960

By Frederick L. Hoffman

These extracts are sufficient for the purpose of emphasizing the practical difficulties of averaging iron-mining conditions so as to make general vital statistics concerning iron miners useful Tor scientific. purposes. It is self-evident that conclusions based upon iron miners, so called, working largely above ground and employed chiefly in open-cut blasting ~perations or the management of steam shovels, etc., can not be made to apply to miners working continuously underground with an exposure of dust and other conditions quite similar to underground mining methods in the extraction of gold, silver, copper, lead, and other ores. The so-called "milling" process as practiced on the Mesabi Range may here be referred to, the same being explained in the report of the Immigration Commission to consist "in the sinking of a shaft on the edge of the ore body from which a tunnel is run in under the ore and connected with a vertical, funnel-shaped hole from under the surface, through which the ore is 'milled' down into the tramcars placed under the opening under the tunnel. After being loaded at the bottom of the funnelshaped hole, the cars are run out to the bottom 0.£ the shaft. where the ore is dumped into skids or elevators and raised to the ~urface and unloaded into the tipple, where it is loaded into thecal'S ready for shipment." It is properly pointed out that the so-called " milling" process employs some of the features of both the open-pit and underground methods of mining. For these and many other reasons it is self-evident that general statistics concerning iron mining are quite likely to be inconclusive and possibly seriously misleading. Aside from the foregoing the problem is seriously complicated by the extensive employment of foreign labor in the iron-mining ind ustries of the Lake Superior districts and of Negro labor in iron mining in Alabama. Within recent years, according to the report of the Immigration Commission, a considerable displacement has occurred in t~e quality of labor employed in iron mining, the displacement bemg referred to as "progressive," in that one race or group of races has entered the region and taken up the work offered in the lower occupations, the race or races already holdinz such positions having. moved up in the scale of occupation leaving the field to the newcomers. This statement is quite suggestive in that it indicates a comparatively short average trade life or trade exposure, quite at variance with the relatively long average ascer- MINES, QUARRIES, ORE REDUCTION, AND SMELTING. 377 tained for the iron mines of New <Tersey. It is said in the report of the Immigration Commission that- The Scandinavians and the other northern European races have given way to the Finns and Slovenians, and in the open-pit mines the Finns and Slovenians have given way to the south Italian, Montenegrins, Croatins, and other southern European races. In the underground mines the common labor and mining is chiefly done bv Finns and Slovenians because the races from the southern countries can not stand the heavy physical work required in this kind of mining. Here, too, is found the same upward movement, for formerly the English (Cornishmen) and Scandinavians' were in the lower occupations in the underground properties, At present the south Italians, Serbians, Montenegrins, and Croatians are performing the most menial work and are the races who are now at the foot of the scale of occupations. It is a matter of conjecture on the ranges as to who will push these races up or whether they will remain the commou laborers of the region. Inquiry was made into the prevalence of diseases OIl the ranges, but more with reference to outside sanitary conditions than to occupational exposure. The most common diseases on the ranges, however, were ascertained to be pulmonary tuberculosis and typhoid fever, and to a lesser extent smallpox and venereal diseases. With -cgard to pulmonary tuberculosis it is said that the disease is most Eevalent among the Finns and the Swedes, and is chiefly imported, I'here is no reference to a possible connection between disease occur- ~ence and occupational conditions, above or below ground, but there .s no evidence that this aspect of the iron-mining industry was made .he subject of a special investigation.

Jan 1, 1918

By James Westfield

Following is a resume of activities of the Division of Coal-Mine Inspection that have had a favorable effect on health, safety, and the reduction o1 injuries at coal mines: 1. The Federal Mine Safety Code for Bituminous Coal and Lignite Mines of the United States was issued originally by the Director of the Bureau of Mines July 24, 1946, after consultation with management and labor representatives of the coal-mining industry. The code has been used by Federal coal-mine inspectors while inspecting bituminous coal and lignite mines as a basis for determining the existence of unhealthful and unsafe conditions and practices in these mines. A revised code was issued by the Secretary of the Interior October 8, 1953, after further consultations with representatives of management and mine workers and was incorporated by reference in the 1952 and subsequent bituminous coal wage agreements. The agreement of May 29, 1946, between the Secretary of the Interior, acting as Coal Mines Administrator under authority of Executive Order 9728, and the United Mine Workers of America, covering bitumi¬nous coal and lignite mines in Government possession, charged Federal coal-mine inspectors with the responsibility of making periodic investigations of the mines and reporting to the Coal Mines Administrator any violations of the Federal Mine Safety Code. Federal coal-mine inspectors also had temporary authority to close mines found to be imminently dangerous, but such authority (under Executive Order 9728) was removed June 30, 1947, when Government control of the mines was terminated.

Jan 1, 1959

By Patrick A. Hamilton

This Bureau of Mines report delineates the coal reserve base of anthracite, bituminous and subbituminous coals, and lignite, by mining method and sulfur content, for coal-bearing States west of the Mississippi River. The parameters used to establish the reserve base definition are the result of a joint agreement by the Federal Bureau of Mines and the U.S. Geological Survey. The reserve base of low-sulfur coal, =10 percent sulfur, is 167,324.5 million tons; medium-sulfur coal, 1.1-3.0 percent sulfur, is 37,531.5 million tons; and high-sulfur coal, >3.0 percent sulfur, is 11,244.1 million tons. The reserve base of coal with an unknown sulfur level is 18,323.0 million tons. The percentages of deep and strippable coal are 56 percent and 44 percent, respectively. The basis for reserve base estimates and analytical data for this report was the Fuels Availability System, a Bureau of Mines data bank containing numerous data tin fossil fuels. Information contained in the system was obtained from publications of the Bureau of Mines, U.S. Geological Survey, State agencies, private publications, and company data.

Jan 1, 1975

By William W. Odell

Certain gas-making processes are in use in Europe, particularly in Germany, which differ radically from those in common use in America. A number of them are of particular interest because they are different. The questions naturally arise: Are any of them applicable to the making of gas in this country and, if so, with what particular type of solid fuel? It is a fact that some of them were developed with consideration of a particular set of conditions and for the utilization of solid fuels available in Germany. The latter fuels, in certain characteristics, are unlike the high-rank fuels commonly used for making gas in the United States; therefore, in attempting to evaluate the various foreign- developed processes with regard to usefulness here, one must give attention to the particular conditions that will prevail in any specified case and also the characteristics and requirements of the process and generator under considera- tion. Three of the processes that were developed and put into commercial operation in Germany, and which have some characteristics in common, are con- sidered in particular in this publication; they are: 1. Lurgi pressure gasification process. 2. Winkler process. 3. The Leuna slagging-type producer-gas process. Each of these processes requires steam and oxygen as gas-maiding fluids. For a number of years, oxygen, has been used in a relatively pure state,. along with steam, in making gas in Germany, and many of the difficulties initi-. ally encountered have been overcome. Although it appears that oxygen recovered from air was first used in this manner as a method of utilizing a byproduct in a plant that used the nitrogen complement in the manufacture of ammonia; more recently, the oxygen was made particularly for the purpose. The fuels - brown coal or lignite used in processes 1 and 2 were not suitable for use in the older and commonly used intermittent-type water-gas generators, and it was necessary, therefore, to devise a different process for gasifying them. A gas of higher heating value than producer gas, was desired, and the use of oxygen (not air) along with steam made possible the production of the desired gas without nitrogen dilution, which characterizes producer gas. Operating data presented herein are based upon observations by, members of the Technical Oil Mission at plants in Germany, on records, and on information vocally given to members of the lässion, including the author, while visiting those plants, and they are believed to be reasonably correct; however, certain hasic observations, comparisons, and conclusions are. made by the author.

Nov 1, 1947

By A. L. Service

Idaho has nearly 6 billion tons of potential sources of phosphorite, 10 to 31 percent P2O5&apos; above and within 100 feet below entry level, the largest potential of any State in the United States. In 1963 Idaho ranked third after Florida and Tennessee in total mine and marketable production of phosphate rock; Montana ranked fourth. This report describes phosphate deposits, mines, and prospects in 10 districts covering most of the Idaho phosphate field. All mine production of phosphate rock in Idaho comes from surface mines and is processed to phosphate fertilizers, phosphoric acid, and elemental phosphorus. Producing districts are Fort Hall (Gay mine), Trail Creek (Conda and Ballard mines), and Crow Creek (Georgetown Canyon mine). FMC Corp. and J. R. Simplot Co. at Pocatello have the largest elemental phosphorus and fertilizer production facilities, respectively, in the State, followed by Monsanto Co. and El Paso Natural Gas Products Co. (formerly Central Farmers Fertilizer Co.). The only other major phosphate processing plant in the State is the phosphoric acid and phosphate fertilizer complex at Kellogg operated by the Bunker Hill Co. In 1963 a plant was constructed and put on line at Monsanto, Idaho, to recover vanadium from ferrophosphorus produced by electric furnace operations in the area. El Paso Natural Gas Products Co. completed construction of a fertilizer and phosphoric acid plant near Conda in 1965. There is a small fertilizer plant producing phosphate fertilizers for local consumption in Soda Springs.

Jan 1, 1966

By Jr. Herty

Ferromanganese continues to be an indispensable requirement in steel manufacture. Approximately 470,000 of the 80 per cent ferro-alloy was consumed in 1929 and increasing amounts will be required annually by the steel industry unless some satisfactory substitute is found. An average of 14 pounds of metallic manganese is used for each ton of steel produced, The principal use of manganese is for de-oxidation of the metal in the steel refining processes, although a considerable amount is also used for the production of special manganese steels. Unfortunately, domestic production of manganese ore is inadequate to meet normal peace-time requirements, not to mention increased abnormal war-time demands. The rather large quantities of low-grade manganiferous iron ores which occur in the Coruna Range in Minnesota have for a number of years greatly appealed to those interested in the development of a domestic source of the supply. The North Central Experiment station of the Bureau of Mines has made an elaborate study of the possibilities of the pyrometallurgical treatment of ores from these deposits and much of the valuable information secured by them has already been published.

Jan 1, 1930

By Oliver C. Ralston

The Nonmetallic Minerals Division of the Bureau of Mines deals with all mineral substances not intended to be used as ores for extraction of metals, with the exception of the fuels. However, coal washing, the methods of which are highly Similar to the concentrating methods for ores, is in¬cluded In the work of the Nonmetallic Minerals Division to facilitate administration and to avoid duplication of equipment. During the fiscal year most of the work of the division was done at the experiment stations in College Park, Md., Tuscaloosa, Ala., and Seattle, Wash.

Jan 1, 1938

By J. F. Shaw

MINE fires are usually extinguished by constructing seals in the approaches to the areas to exclude air from the fire areas, which smothers the fires in an oxygen-depleted atmosphere. Seals should be substantially constructed and made as nearly airtight as possible and should be provided with a sampling pipe so that samples of the atmospheres behind the seals may be collected at regular intervals. Methods of constructing seals and of sampling and analysing mine atmospheres are fully described in Bureau of Mines publications. (1, 2). Information obtained on the composition of atmospheres behind fire seals is helpful in determining if a fire has been extinguished or if there is any danger of an explosion when a fire area is being sealed or unsealed. The progress of a mine fire can best be determined by studying percentages of carbon dioxide, carbon monoxide, and hydrogen in the atmosphere behind the seals. Hydrogen will be formed in a bituminous- or subbituminous-coal mine when the temperature exceeds 480° F. and in an anthracite mine when the temperature exceeds 660° F. (3). Carbon monoxide and carbon dioxide are both products of combustion of coal, wood, or other organic compounds. The presence of carbon monoxide has long been accepted as an indication of a mine fire. A sealed fire area should not be reopened until the carbon monoxide has disappeared. Trends in the percentage of carbon dioxide are also useful in determining the status of a mine fire. Carbon dioxide is sometimes liberated by rock strata. In this case, carbon dioxide in the atmosphere behind a seal will be from two sources-the rock strata and the fire. When the, fire is extinguished, carbon dioxide will be liberated from only I source, the rock strata, and when the percentages of carbon dioxide are plotted, the slope of the curve will not be as steep as when this gas was being liberated from 2 sources. If the only source is the fire, the percentages of carbon dioxide will gradually decrease after the fire has been extinguished. By studying analyses of a mine-fire atmosphere, it is possible to determine if the atmosphere is explosive; if the mixture is capable of becoming explosive when mixed with air; and if the mixture can be made nonexplosive or be prevented from becoming explosive by being mixed with an inert gas. These factors can be computed mathematically or determined graphically. The mathematical calculations advanced by Ash and Felegy (7) are discussed, and graphical solutions of their equations are presented. It is believed that the graphical solution will be extremely helpful in determining the characteristics of a mine-fire atmosphere when fighting a fire, because the results can be obtained in a matter of minutes, and there is less likelihood of an error being made under the stress incident to control efforts. The experimental and theoretical work upon which the formulas are based have been adequately described and are not discussed at this time (5) (6).

Jan 1, 1955

By Oliver C. Ralston

The Nonmetallic Minerals Division of the Bureau of Mines deals with all mineral substances not intended to be used as ores for extraction of metals, with the exception of the fuels. However, coal washing, the methods of which are highly Similar to the concentrating methods for ores, is included In the work of the Nonmetallic Minerals Division to facilitate administration and to avoid duplication of equipment. During the fiscal year most of the work of the division was done at the experiment stations in College Park, Md. Tuscaloosa, Ala., and Seattle, Wash.

Jan 1, 1938

By Charles C. Myers, Robert M. Doerr

The apparatus described was developed for determining the kinetics of gas - solid reactions at high temperatures by measuring the volume of gas consumed with respect to time . This apparatus consists essentially of a horizontal precision- bore glass tube connecting a small reaction chamber in a furnace to a large constant - temperature reservoir . A drop of mercury in the tube separates the two sides of the system and serves as an indicator that moves at a speed proportional to the rate of gas consumption . The sensitivity of the apparatus depends inversely on both the density of the gas in the system and the cross - sectional area of the tube ; with a tube having an area of 0.079 cm² , the sensitivity for oxygen at 308 ° K and 0.5 atm is 20 cm/mg . The reproducibility of data with the volumetric apparatus is good .

Jan 1, 1964

By Frank L. Gaddy

In this report, a description of mine practices, the preparation of roof bolts for laboratory experiments, the results of tensile-strength determinations, and a discussion of results of these tests are presented. Certain restrictions are recommended for roof bolts subjected to repeated bending, and two methods of complying with these limitations imposed by the restrictions are presented. The practice of bending steel roof bolts for installation in areas where the height of the opening was less than the length of the bolts required to support the immediate roof adequately has been adopted recently in several coal mines in lieu of sectional rods designed for that purpose. In addition, a few of these same mines have been reclaiming the bent rods and reusing them numerous times. The purpose of this study was to determine if these practices decreased the strength of such bolts and thus jeopardized the safety of the men working in these mines.

Jan 1, 1958

By C. C. Clark

This report presents the results of tests conducted by the U.S. Bureau of Mines to determine the transport characteristics of highly concentrated paste backfill mixes made from dewatered total mine tailings. The slurry concentrations of the mixes were all above 78 pct by weight with slumps ranging from 6.4 to 16.5 cm (2.5 to 6.5 in). Laboratory material property tests and full-scale pumping tests were conducted using pipe diameters of 102, 128, and 154 mm (4, 5, and 6 in) and a positive-displacement pump. The results indicated that the tested backfill mixes can be successfully transported as a stiff paste and identified the influence of and the interaction among the various mix and system variables.

Jan 1, 2010

By McClelland. John J.

This Bureau of Mines report discusses recent applications of water in-fusion technology to control dust in U.S coal mines and presents recommended guidelines for determining coal seam infusibility. The techniques required to use water infusion are presented in detail. A Bureau case study indicated that water infusion reduced dust levels by 68 pct along a longwall plow face, bringing this section into compliance with the Z.0-mg/m3 Federal dust standard. Similar studies conducted by Occidental Research Corp. under a Bureau contract show water infusion at two longwall double-drum shearer operations produced dust reductions ranging from 38 to 50 pct. Water infusion was found to be cost effective, aver-aging 5 cents per ton.

Jan 1, 1987

By T. F. Anstett

The Bureau of Mines evaluated the potential availability of chrysotile, amosite, and crocidolite asbestos from 42 properties in market economy countries. This resulted in the development of tonnage-cost relationships indicating the quantity of grades 3 through 7 asbestos at various average total costs of production at 0% and 15% rates of return on invested capital. The availability of grades 2 and 8 was also evaluated, but since each is produced at only one property, no analytical results were given. Total demonstrated recoverable chrysotile fiber potentially available of grades 3 through 7 from the 42 properties evaluated follow: 1.59 million t, 21.00 million t, 16.74 million t, 15.54 million t, and 19.27 million t, respectively. The total amount of crocidolite is 1.69 million t. Owing to the good potential for discovery and development of new deposits, long- term availability of fiber of all three types is not in jeopardy. However, many of the crocidolite properties evaluated in the northern Cape crocidolite field of South Africa have relatively small demonstrated resources, and new deposits will have to be exploited by the late 1990&apos;s to sustain projected levels of production.

Jan 1, 1985

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 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 results that may be applied to the engineering analysis and solution of mining problems. SUMMARY Operation of a limestone quarry producing flux for the steel industry and crushed stone for production of concrete is described in this report. The deposit being mined is a flat-lying limestone formation under a thin overburden 2 to 25 feet thick. The height of the quarry face varies from 9 to 60 feet, averaging 40 feet. Production rate ranges from 4.5 to 5 million long tons per year.

Jan 1, 1959

By Lloyd H. Banning

ELECTRIC smelting tests were conducted at the Northwest Electro-development Experiment Station, Albany, Oreg., to develop a feasible process for producing silicomanganese from siliceous manganiferous material. The Jackson County, Oreg., material used was massive and contained rhodonite as the most abundant mineral. Both raw and beneficiated materials were tested; various proportions and types of fluxes and reductants were used to make up the furnace charges. The silicomanganese product was used successfully in manufacturing various steels at industrial plants. The manganese content of the samples ranged from 23 to 28 percent; silica plus alumina content was as high as 55 percent-about four times the maximum specification for Metallurgical-grade ore. Sink-float laboratory tests indicated that the manganiferous material was amenable to beneficiation. Over 2 tons of rhodonite concentrate was prepared for smelting tests in a sink-float operation. Only the minus-3/4-inch, plus-8-mesh fraction was fed to a heavy-medium cone; over 97 percent of the manganese was recovered in the sink product, which contained 32.4 percent manganese and 44 percent silica plus alumina. About 25 percent of the silica was removed in the float product.

Jan 1, 1959

By John A. Burgess

The Carson Hill mine of the Carson Hill Gold Mining Corporation is at Melones, Calaveras County, Calif. It is one of the numerous mines on the Mother Lode of California. The property extends for 8,400 feet along the outcrop of that important vein system. The elevation at the haulage level is about 1,000 feet above sea level. ACKNOWLEDGMENTS Acknowledgment of assistance in the preparation of this paper is made to Frank Wagner, underground superintendent; Max Petersen, engineer; and Homer Mann, assistant engineer. The geology of the Mother Lode has been described by Adolph Knopf in Professional Paper 157 of the United States Geological Survey; references to general geology have been abstracted largely from Knopf.

Jan 1, 1937