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By Paul L. Russell

This property has been examined several times in the last few years , and findings have been reported . In the fall of 1942 , the author supervised sampling both lode and placer deposits . The ore was beneficiated , and the results obtained are incorporated in this report . stia The Morgan Group , which comprises seven unpatented mining claims and the Black Cat placer claims , was purchased by the Manganese Products Corp. from H. D. Hill of Hatch , N. Mex . , and Dr. A. C. White of Hot Springs , N. Mex . Arthur L. McRowe , 876 27th Avenue , San Francisco , is president of the corporation , and David Fewer, 824 Times Building, Long Beach, is treasurer . J. T. Murray is in charge of operations .

Feb 1, 1947

By R. C. Wang

Solid-liquid flow in different pipe geometries was investigated. This investigation was conducted by measuring delivered solids concentration and head loss. The delivered solids concentration was measured to study the effect of pipe geometry on the minimum carrying velocity above which solids do not lag behind the fluid. Head loss was measured to study the effect of pipe geometry on the friction loss. A mathematical formula was developed for determination of the minimum carrying velocity. Darcy-Weisbach's equation and Durand's equation were used for comparison of head losses of pipe shapes. Of the different pipe shapes studied, each having the same interior cross-sectional area, the rectangular pipe with the wide side oriented as the base yielded the lowest minimum carrying velocity at high solids concentrations. The minimum head loss at low velocity and high solids concentration also was attained with this pipe. Although the circular section is known to be the best for transporting liquid only, the present study suggested that pipe geometry is a factor in lowering the operating velocity and reducing head loss in solid-liquid flow.

Jan 1, 1973

By E. T. Bowers

Pneumatic conveying of coal underground is not widely used in the United States, although it is becoming increasingly popular in Great Britain, the Federal Republic of Germany, and South Africa. The question of safety has been raised repeatedly: Will the system be prone to dust or gas explosions, and, if so, can it withstand such occurrences safely? The work reported here was done under a Bureau of Mines contract and deals with the safety aspects of pneumatic transport of underground coal, as well as the hazards inherent in more conventional haulage systems. Included are three designs for different applications of pneumatic haulage: off-loading a continuous-mining machine on a room- and-pillar section, vertical hoisting through a 1,200-ft shaft, and off-loading a tunnel-boring machine driving a 2,000-ft tunnel.

Jan 1, 1985

By W. L. Falke

Procedures in which manganese compounds are reduced and the metal is volatilized and selectively condensed, a hitherto neglected area, were investigated. More than 95 percent of the manganese was recovered from high-melting-point ores whether vacuum volatilization or atmospheric pressure volatilization was used, but neither process is economically attractive under present price-cost conditions.

Jan 1, 1966

By Raja V. Ramani

The recognition that surface mining need not be viewed as a permanent dedication of the land but rather as a temporary non-renewable use in a series of land uses has caused greater emphasis on the re-use of surface-mined lands. In an effort to develop a procedure for evaluating postmining land use potentials, specific mines in various regions of the U.S. have been studied to determine the extent of current mined-land planning and to discover characteristics that are regional in nature. As part of this investigation, the Indian Head Mine, which is located in Mercer County, North Dakota, has been studied. The Indian Head Mine is presently operated by The North American Coal Corporation -Western Division and has been in operation since 1917 under various ownership. The status of current reclamation and postmining land use planning was reviewed. In addition, the relationship between mine planning and public planning in an area impacted by energy development was investigated. Finally, key factors affecting site potential realization for western surface mines have been identified.

Jan 1, 1983

By Barton K. Cross

The objectives of this effort were to: 1) Develop and validate start-of-shift operational inspection procedures to be used by operators of mobile, self-propelled equipment used in surface mining operations; 2) Evaluate user acceptance of the developed procedures; and 3) Recommend methods and media for presentation of the developed procedures to the user population. Mobile, self-propelled surface mine equipment requiring start-of-shift inspection was identified. Subsystems amenable to operational inspection were identified. The procedures addressing all safety critical subsystems on each equipment type were then developed and validated. The inspection procedures developed were those that could be performed largely from the operator's station. User acceptance was evaluated during on-site data collection visits to surface mines. Representatives of the user population reviewed the procedures and were then interviewed. Recommendations for the methods and media of presentation to the user population were developed from information obtained in: 1) Review and analysis of instructional technology literature applicable to this area; 2) On-site data collection; and 3) Analysis of the working environment and characteristics of the user population.

Jan 1, 1977

By John A. Johnson

Conclusions regarding the use or omission of stemming in blasting have not peen reached, pending completion of all aspects of this investigation. The results from the dust phase of this study on six classes of stemming prove that the kind of stemming affects the amount of dust produced from blasting. In previous work at the Mount Weather testing adit it was demonstrated that blasting produces the highest dust concentrations of any of the mining processes.5/ Under the conditions prevailing at the Mount Weather testing adit, the average of all rounds having a break of at least 95 percent showed that the least amount of dust was produced when no stemming was used.

Jan 1, 1940

By Frank J. Cservenyak

Curtailment of bauxite importation by enemy activities during World War II focused attention on the necessity of developing domestic deposits of aluminous materials. Large quantities of aluminum ores such as kaolin, siliceous bauxites, high-iron bauxites, anorthosite, and diaspore clays are available but not readily amenable to Bayer processing because of excessive impurities. The Bayer process, which is the only commercial method in use in the United States for producing metallurgical-grade alumina, requires a high Al2O3 bauxite relatively low in SiO2 and Fe2O3. The Bureau of Mines was charged by Congress to investigate processes for the production of alumina from these low-grade ores. One part of the program was an investigation, in the laboratory and pilot plant, of the recovery of alumina by the lime-soda sinter process. Ores comprising kaolin, diasporic clays, anorthosite, and siliceous bauxites have been investigated and studied in the laboratory and pilot plant, and a series 'of reports covering these investigations has been prepared.

Jan 1, 1948

By Chase E. Sutton

The porosity of a sand is usually the measure of its capacity for holding fluid, although porosity is sometimes selective; that is, a small percentage of the actual pore space (voids), particularly in fine-grained sandstones, may be isolated by the cementing material which prevents the entrance of fluids under normal conditions. Obviously, however, porosity determinations are essential to an engineering study of underground conditions of an oil field, and a simple and reliable method of obtaining a reasonably accurate figure for average porosity is desirable. This report describes a method suggested by Ruasell,3 which was used by the writer in the preparation of a report on the Texhoma-Gose pool, Archer County, Tex.4 The conditions in this pool were particularly favorable for obtaining an average porosity figure, in that some 30 to 35 core samples of the pay sand were available for analysis.

Jan 1, 1928

By Rose L. Ballard

This chapter summarizes data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rico. Included also are the tables that show the principal nonfuel mineral commodities exported from and imported into the United States and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of Volume I and in the State chapters of Volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at any of several stages of extraction and processing, the stage of measurement used in this chapter is what is normally termed "mine output." It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines.

Jan 1, 1985

By Daniel C. Boteler

Data from 68 entrained-bed carbonization tests were treated statistically by the Bureau of Mines, and several useful relationships were developed among the major variables. Nine coals, ranging in rank from lignite A to high-volatile A bituminous, were carbonized in two entrained-bed carbonization pilot plants. The carbonizing reactors employed were vertically mounted cylinders, internally heated, refractory-lined, and 10 inches ID. The range of carbonization temperatures was from 825° to 1,600° F. Using a regression-analysis computer program, empirical equations were developed by which carbonization temperature, air-to-coal ratio, devolatilization of coal, char yield, and volatile matter content of product char may be predicted.

Jan 1, 1973

By R. W. Stahl

An award is a form of recognition given for superior performance in a special field of endeavor. Each year awards are given by the Joseph A. Holmes Safety Association and the National Safety Council to mineral industries' mines, quarries, and plants that have worked a specific number of man-hours without a lost-time injury. These awards have a dual significance in that they prove that efficiency can be attained without injury to persons. Safety awards do not result from luck or good fortune but do result from sincere desire coupled with sufficient effort and cooperation to achieve a desired goal.

Jan 1, 1963

By D. T. Hahn

Adequate and cost effective erosion control is an important component in most plans for reclamation of surface mined land. Despite the fact that much is known about erosion of agricultural lands, insufficient conclusive knowledge is available about erosion of reclaimed surface mined land. Our study was conducted to characterize the erodibility of reclaimed surface mine land relative to unmined cropped land, and to evaluate the accuracy of the universal soil loss equation (USLE) in estimating erosion from reclaimed soils. A rainfall simulator was used to measure runoff and erosion rates from plots at three Indiana surface mines. The relation of erosion of the reclaimed soils was not completely constant with that from the cropped soils. Significant differences in erodibility were observed between reclaimed and nonreclaimed top soils, as well as reclaimed topsoils and reclaimed subsoils.

Jan 1, 2011

By J. H. Maysilles

The Bureau of Mines is examining a variety of low-grade uranium ores because projections indicate that an appreciable percentage of future U.S. uranium production will be derived from resources containing 0.01 to 0.1 percent U308. One possible source is represented by a granitic material from Wyoming; the available samples contained 0.06 and 0.12 percent U308. Tests were conducted to explore the general leaching characteristics of this potential resource. The material responded to both acidic and alkaline leaching techniques. Conventional acid leaching extracted 93 percent of the uranium in 18 hours; the required acid addition was 50 to 100 pounds of H2S04 per ton of ore, and the oxidant addition was 3 pounds of NaCl03 per ton of ore. The acid consumption continues after maximum uranium recovery has been reached; this effect may complicate heap or in situ leaching with acidic solutions. Some variation in reagent requirements was noted between the two ore samples. Conventional carbonate leaching with strong solutions at 85° C extracted 94 percent of the uranium in 24 hours. These granitic materials also showed some response to dilute carbonate solutions, and the results suggest that the material may be chemically amenable to heap or in situ leaching with dilute carbonate solutions.

Jan 1, 1977

By McHenry Mosier

Although local conditions at each mining property affect the percentage of increase in drilling speed for a given reduction in gage of bit, the results of drilling tests conducted at the Mount Weather testing adit show such a large advantage in favor of the smaller gages that they should be indicative of the possibilities at most mines. GENERAL DISCUSSION Although it is common knowledge among miners that drilling speed ill- creases with reduction in gage of bit, the large amount o this increase is not so universally realized, A recent Bureau of Mines4/ survey of drilling practices in 28 metal mines showed that the maximum gage of starters is 3 inches and that at 50 percent of the mines starters are 2-1/4 inches or larger, Because this size appears too large for conditions at most' mines where abrasion is moderate and where powder distribution permits, the use of smaller bits presents a favorable opportunity for reducing drilling costs.

Jan 1, 1939

By L. F. Christianson

The presence of salt in crude petroleum has been known for many years, but recently the percentage of chloride salts of calcium, magnesium, and sodium produced with some crude oils has increased to such an extent that the removal of the salty compounds is imperative for some refiners and their presence causes considerable apprehension for others. The exact reason for this increase of salts is not known definitely, but in all probability a combination of factors contributes to the condition. The most important are acidizing of wells, development of new fields producing crude oils of greater salt content, and the depletion of old fields with an attending increase in the production of emulsified brine. Due to handling

Jan 1, 1938

By William E. Wallace, S. J. Page, B. L. Razzaboni, C. A. Hill, Pamela Mike, P. Bolsaitis, M. J. Keane, Val Vallyathan

"Respirable quartz cytotoxicity, as measured by erythrocyte hemolysis and pulmonary macrophage release of lactate dehydrogenase in vitro, is neutralized by boiling in water in glass test tubes for 10 to 40 minutes. The cytotoxicity is reduced to near zero by boiling l to IO mg quartz per milliliter water. For greater concentrations of quartz in water the hemolytic potential after 40 minutes of boiling approaches that of native quartz. Replacing the medium with fresh water midway through boiling results in full detoxification through 20 mg quartz per milliliter water. Pre-boiling the medium with silica reduces the detoxification effect. Detoxification persists after mild drying at l 10°C for 8 hours, and persists after three days of resuspension in water at room temperature.INTRODCJCTIONResearch underway to determine interactions of quartz and other mineral dust surfaces with pulmonary fluids and alveolar macrophages in culture led to the observation that when dusts were autoclaved in aqueous suspension, their cytotoxic effects on macrophages were suppressed, in some cases fully and even after several days incubation with the cells. This finding was in direct contradiction to earlier results from both short term macrophage lysosmal enzyme release assays, as well as longer term cytotoxicity assays from macrophages in culture; in those studies, dusts were steam autoclaved at 121°C with no liquid water but with steam present. 1.2 However detoxification under boiling conditions has been reported in other research. 3 It was decided to use the hemolysis assay to further investigate these findings, because of its sensitivity simplicity and cost.RESCULTS AND DISCCISSIONRespirable quartz dust used in this study was taken from a stock of crystalline silica, Min-U-Sil; obtained from Pennsylvania Sand Glass Corporation, fractionated in air with a particle classifier. The small size fraction retained for use was 80% less than S micrometer particle diameter, with an area equivalent median diameter of 1.24 micrometers as estimated by automated image analysis. The silica was at least 98.S mass percent silica as determined by X-ray energy spectrometric analysis; and the crystalline form was alpha-quartz as determined by X-ray diffraction. It's specific surface area was 3.97 square meters per gram as determined by nitrogen adsorption isotherm methods. I"

Jan 1, 1990

By Kelly C. Strebig

Laboratory tests were conducted by the Bureau of Mines to determine the effect of depth of cut and bit type on respirable coal dust generation. Apparatuses were constructed to contain the coal samples, measure the linear cutting forces, and analyze the dust generated. Single-bit tests were conducted in Illinois No. 5 and Pittsburgh seam coals with five bit types at four depths of cut. The results showed that bit type did not significantly influence dust production. On the other hand, deep-cutting bits were more efficient and generated substantially less respirable dust per pound of coal broke than shallow-cutting bits.

Jan 1, 1975

By Robert L. de Beauchamp

The Bureau of Mines reviewed aluminum chloride technology to determine the problems associated with its preparation from minerals, and to ascertain the best areas for research to solve these problems. Commercial AlC13 production processes are described and the ?state of the art? for the preparation of AlC13 from aluminous materials is evaluated. Areas for further research are indicated.

Jan 1, 1969

By Richard E. Dawes

Physical variables, a principal factor in the economies of mineral production, affect both capital and direct operating costs. By using a revenue-cost system for the framework, the analyses of revenue and cost categories demonstrate the relative importance of groups of physical variables, whether explicitly defined or not, to a lead-zinc mining operation. Physical variables affecting the producer represent about 60 percent of the total system influence as expressed by cost ranking. Other physical variables affect the remaining costs as controlled by the smelter, the transporter, and the landowner. Such resource conservation aspects as mineral losses due to mining method and mineral processing constitute a portion of the total revenue effects of physical variables. The physical variable revenue-cost system presented in this report offers a framework for cost-benefit analysis of mineral related research.

Jan 1, 1969