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By Forrest T. Moyer, Nina L. Jones, Mary B. McNair, Virginia C. Berté

To keep the mineral and allied industries informed of trends in the causes of accidents, and to point out the need for corrective measures, the Bueau of Mines collects, analyzes, and periodically publishes health and safety statistics. This report includes data for 1963 on injury experience, with related employment statistics, at coal mines in the United States. These data are presented in tabular form under the following headings:

Aug 1, 1965

By John D. Sullivan

In leaching copper ores knowledge of the rate of dissolution of the copper minerals and of the impurities is desirable. With knowledge of these two factors and data as to what minerals are present in the ore the metallurgist has an excellent start on planning a leaching cycle to fit that ore. The rate of dissolution is rather difficult to predict, and the time required to leach a given ore may differ markedly from that required by another ore. The whole study as related to mixed oxidized and sulphide ores is one of relative rates of dissolution of the different copper minerals and the impurities in sulphuric aoid and in ferric sulphate. The aim of leaching is to choose a cycle and strength of solvents to extract a maximum amount of copper and a minimum of impurities. The consumption of reagents per unit of copper dissolved is a function of the strength of the reagents used and the relative rates of attack on copper minerals and impurities. An opportunity may exist of obtaining the kind of electrolyte wanted for electrolytic precipitation and yet of saving on the consumption of reagents by modifying the strength of ferric sulphate and of sulphuric acid during the cycle to fit the time needed for dissolving the sulphide and oxidized minerals present.

Jan 1, 1931

By Michael J. Magyar

This report contains a cost estimate of the Bureau of Mines process for dewatering Alaskan placer effluent streams with polyethylene oxide (PEO). In this process effluent slurry is withdrawn from the placer plant pond system after a primary settling stage. A dilute PEO solution is injected into the slurry line to flocculate the fine, suspended solids. The flocculated solids are dewatered on a stationary screen. Clarified water is returned to the placer operation or discharged, while the 35 percent solids waste is pumped back into the mine cut. Cost estimates are presented for dewatering plants processing 1,000 gallons per minute of effluent slurry at three representative turbidity levels. Both the placer and the dewatering plants operate on the same 1-shift-per-day, 6-day-per-week schedule for the 100-day Alaskan operating season. Estimated fixed capital costs for these plants processing placer with effluent turbidities of 1,000, 3,000, and 5,000 nephelometric turbidity units (NTU) are approximately $29,000, $31,000, and $34,000, respectively, on a fourth quarter 1986 basis. Operating costs are estimated to be $0.34, $0.37, and $0.40 per thousand gallons of effluent slurry.

Jan 1, 1987

By E. B. Kester

In the commercial evaluation of coal tars, a distillation analysis properly carried out is of considerable importance. Close attention must be given to this operation in order to obtain consistent results and to secure the minimum decomposition of the tar compounds, which in many cases are sensitive to undue heat effects. Low-temperature tars in particular contain compounds of this nature, while in the case of tars produced at high temperatures the large proportion of pitch present has an adverse influence during a distillation. If excessive cracking takes place, the composition of the distillate will naturally vary from the normal, with the result that all the analytical criteria subsequently obtained are affected. Where tars, produced over vide ranges of carbonization temperatures are investigated as in the survey of gas, coke, and by-product making properties of American coals nor being conducted at the United States Bureau of Mines Pittsburgh Experiment Station, the method of distillation must necessarily be the sane for all of the tars studied. Also, it must function equally well for both low and high temperature tar, permit accurate fractionation, and reduce adventitious decomposition to a minimum.

Jan 1, 1932

By H. G. Iverson

The effects of adding boron and boron plus carbon to electrorefined vanadium were evaluated with respect to mechanical properties at low temperatures and response to heat treatment. Grain size was significantly decreased with the addition of 0.05 percent boron, the decreases ranging from 30 percent at 800° C to 75 percent at 1,100° C. Increasing the boron content resulted in only a small increase in strength at room temperature, but at 77° K, boron contents of 0.005 to 0.076 percent increased the yield strength of vanadium over 50 percent, from 70,000 psi to 110,000 psi. When boron and carbon were present together, the individual grain-refining effects obtained with either element were retained. Approximately a twofold increase in strength was obtained by age-hardening the alloys containing both boron and carbon. Alloys with only boron additions did not age-harden.

Jan 1, 1968

By Robert W. Smith

In a certain application2/ it was necessary to compute the beta function B(p, q) for a certain set of values p and q. Since t he set of p and q values was much mo re finely spaced than those in any published tables, the authors decided to make their results available in this report. In connection with this application the functionB(p, q) was needed at various points in the p, q plane at intervals of 0.05, 0.05<p = q< 10.00. Fletcher, Miller, and Rosenhead2/ state that the only tables available in the desired range are those of Rearson.4/ However, the interval used by Pearson was not small enough for the present application. For this reason it was decided to calculate B(p, q) for p = q =0.05 (0.05) 10. 00.2/ This table is published because of the fundamental importance in mathematical analysis of the complete beta function.

Jan 1, 1953

By Mark Sheppard

This paper is the third of a series recording the results of tests made at various quarries throughout the United States to determine (1) the relation between the size gradation of feed to, and product from, primary crushers, (2) the particle shape of the crushed. product, (3) the differences in gradation and particle shape produced by different types of primary crushers, and (4) the differences in gradation and particle shape caused by crushing different kinds of stone. Progress reports 1 and 2 dealt with comparisons of different types of crushers crushing the same type of stone. This report deals with relation¬ship between feed and product of two different limestones, as to size distribution and particle shape, when crashed in the same crusher.

Jan 1, 1938

By Hillary W. St. Clair

This report gives the results of an experimental study of the progressive changes that occur in particle size and size distribution when a homogeneous and isotropic mineral is subjected to crushing by impact. The mineral used in the study was uniformly sized quartz, which was crushed in a simple drop¬-weight machine that applied impact energy up to about 100 kg-cm per g. Screen analyses of the crushed products were analyzed by the method of moments to determine the mean size, variance, skewness, and kurtosis. Analysis of the data from these experiments shows that the mean size of the crushed product is a function of the energy input and the initial size. The size distribution is functionally related to the degree of size reduction. As the mean particle size is decreased, at first there is a corresponding increase in the variance and decrease in the skewness, But, as size reduction is carried further, each tends eventually to approach a steady value, and the form of the size distribution becomes stable.

Jan 1, 1972

By E. C. Lane

The motor gasoline which is being marketed in the United States this summer is apparently more volatile than the gasoline sold a year ago. In fact the average volatility of this summer&apos;s gasoline is almost the same as the average volatility of the gasoline marketed last winter. During the past seven years the Bureau of Mines has made semi-annual surveys of the gasoline marketed in the United States, the survey just completed being the fourteenth in the series. The cities in which samples have been collected have been chosen as representative of the more important marketing territories as it is obviously impracticable to obtain a sample of every gasoline sold in the entire country.

Jan 1, 1926

By Joan T. May

The Federal Bureau of Mines investigated the potential for recovering aluminum from copper-dump leach liquors by use of single-contact ion-exchange technology. A strongly acidic ion-exchange resin was used to extract aluminum from a typical dump leach liquor and from synthetic leach liquors. Aluminum was stripped from resin with a HS04 or NaCl solution. Bench-scale experiments indicate that a single-contact ion exchange is technically feasible, but that the process is limited by the relatively low loading capacity of the resin and the excessive amount of stripping agent required. A further limitation is that significant amounts of magnesium and iron are loaded and stripped along with the aluminum.

Jan 1, 1976

By Joseph A. DeCarlo, Eugene T. Sheri dan

The process of converting coal into coke is known as carbonization. Essentially, carbonization is destructive distillation in which the volatile matter of coal is released when coal is heated above its decomposition temperature and passes through a plastic stage before solidifying and forming coke. The mechanics of coke formation are complex, and the specific properties of certain coals that allow them to "cake" or form coke are still unknown. Coke is a hard, cellular, carbonaceous mass, formed by heating coal in the absence of air. It is porous, irregular in size and shape, and is similar in appearance to wood charcoal. Coke, however, is denser, more porous, and more abrasive than charcoal. Coke has been in use for several thousand years. History has recorded its use in Greece before the birth of Christ, and it is thought to have been used in China even before that time. It was not until the l6th century, however, that a method for coking was developed in Europe that subsequent ly evolved into the coking process that is known today. The coke industry in the United States began in the latter half of the 19th century when beehive-coke ovens were built to supply fuel for iron blast furnaces. Before this time, an iron industry fueled principally by charcoal had been in existence for several hundred years. With the depletion of timber resources, coke gradually replaced charcoal as blast-furnace fuel, and by 1875 more iron was made with coke than with any other fuel. Before 1893 a 11 coking was done in beehive ovens. These ovens are refractory kilns with arched roofs, sometimes joined together to form batteries.

Jul 1, 1964

By M. M. Barr

Rapid expansion of the titanium-metal industry focused attention upon ilmenite as a possible substitute for the more expensive and less abundant rutile in producing titanium tetrachloride. Most of the rutile available for this use is imported. Preliminary studies were undertaken to determine the chlorination characteristics of high-titanium slags produced by electric-arc furnace smelting of alluvial Idaho ilmenite at the Federal Bureau of Mines Northwest Electrodevelopment Experiment Station, Albany, Oreg. Low silicon, calcium, and aluminum contents of the slags enhanced their potential value for chlorination.

Jan 1, 1958

By Charles L. Parsons, R. B. Moore, S. C. Lind, O. C. SCHAEFER

Early in 1912, from information received by the Bureau of Mines, it became evident that quantities of valuable radium-bearing ore from Colorado were being exported for manufacture in foreign coun- trics and that at least part of the manufactured product was being returned to this country and sold at a price entirely incommensurate with that received by the miner and the prospector. Consequently, in line with its efforts to increase efficiency in the mining and treat- ment of mineral resources, the Bureau of Mines undertook an inves- tigation of conditions. Results of this preliminary investigation were published, in the summer of 1913, as Bulletin 70, which gave an out- line of the radium deposits of the West, the conditions of mining, the wastes involved, and the status of the production of radium from its ores. At about this time newspapers and medical journals were publish- ing statements regarding the value of radium in cancer therapy. These reports, although many of them were exaggerated, brought out clearly the remarkable virtue of the gamma rays for the treat- ment of cancer and other malignant growths. In view of the fact that the largest known supplies of radium ore in the world are in the States of Colorado and Utah and on the public lands of the United States, it was deemed highly important for the Bureau of Mines to study the production of radium in detail. Such study, it was hoped, would enable the prospector and miner to obtain a fairer price for the ores and would furnish information necessary in case Congress appropriated funds to develop methods for extracting radium from ore on the public lands under Government supervision, to be supplied at cost to the hospitals of the Army, Navy, and Public Health Service.

Jan 1, 1915

By Mark Sheppard

This paper is the third of a series recording the results of tests made at various quarries throughout the United States to determine (1) the relation between the size gradation of feed to, and product from, primary crushers, (2) the particle shape of the crushed product, (3) the differences in gradation and particle shape produce- by different types of primary crushers, and (4) the differences in gradation and particle shape caused by crushing different kinds of stone. Progress reports 1 and 2 dealt with comparisons of different types of crushers crushing the seine tyre of stone. This report deals with relationship between feed and product of two different limestones, as to size distribution and particle shape, when crashed in the same crusher.

Jan 1, 1938

By Hal J. Kelly

A picture of the ceramic industrial potential of the Pacific Northwest States is presented by reviewing the present ceramic industries, raw-material resources, and current market demands. A resume is given of the industrial plants manufacturing ceramic ware as well as available information on raw-material resources. No attempt was made to prospect for new deposits but rather to evaluate, insofar as possible, those already known. Since much of the industry is concentrated on the Pacific coast, most of the information available on resources concerns deposits in that area. Large, undeveloped districts in Montana and Idaho, however, offer promise of larger reserves of ceramic raw materials. Average annual production, some operating costs, and annual power consumption are given for each of the plants. Production and some cost figures are listed to show the limited nature of the present industry and to suggest fields open for new development.

Jan 1, 1956

By Kenneth M. Earl

In its investigation of deposits of strategic minerals, the Bureau of Mines did some diamond drilling at the Almedia deposit In an endeavor to find an additional source of supply of lead and zinc. It is reported that in 1816, lead and zinc minerals were found in the limestone quarries near the boundary line between Scott and Center townships. In an attempt to develop these minerals in paying quantities, an alit was driven for several rods into a bluff Just west of the present Almedia mine, This is believed to be the Web mine, mentioned briefly by Parker Cleaveland in 1816. In 1901 the Almedia mine was developed by an open cut and three shafts. The hoisting shaft at the time of drilling by the Bureau of Mines was sounded to a depth of 115 feet. A concentrating plant reportedly made shipments to Hamburg, Germany, for reduction. The deposit is in a somewhat slaty limestone. The ore occurs in a northeast fracture zone along the strike of the limestone and dips to the southeast. Old miners state that the ore appeared as large chunks of galena and sphalerite. In 1949, to investigate the downward extension of the oreshoot, the Bureau of Mines drilled four holes aggregating 1,126.3 feet.

Jan 1, 1950

By L. M. Demers, D. C. Kuhn

"Kuhn, Douglas C., and Laurence M. Demers. Effect of surfactant on basal and silica-induced eicosanoid production by the alveolar macrophage. Am. J . Physiol. 269 (Lung Cell. Mol. Physiol. 13): L165-Ll 70, 1995.-Infiammation and fibrosis subsequent to the inhalation of certain mineral dust particles has been suggested to result from the activation of eicosanoid synthesis by the alveolar macrophage (AM). To determine if surfactant modifies dust-induced generation of eicosanoids by the AM, we evaluated the effect of the surfactant lipid dipalmitoyl lecithin (DPL) on the production of eicosanoids by rat AM exposed to respirable silica dust in vitro. During the first 24-h exposure period, DPL alone significantly increased basal production of eicosanoids but completely inhibited silica-induced thromboxane A2 synthesis. In contrast, leukotriene B4 (LTB4 ) production was only partially reduced by DPL. During a second 24-h exposure period, LTB4 production in response to the highest dose of silica remained significantly elevated in the presence of DPL. Similar results were obtained when the surfactant preparation Survanta was evaluated. These results suggest that 1 ) DPL and Survanta independently activate AM eicosanoid production, 2) DPL and Survanta modulate the response of the AM to silica dust, and 3) L TB4 may be the most important eicosanoid mediator of the long-term effects of silica dust exposure on lung pathophysiology. THE OXYGENATED METABOLITES of arachidonic acid (AA) (here collectively termed eicosanoids) have been implicated as important regulators of lung physiology and are thought to be involved in pathophysiological sequelae such as acute respiratory distress syndrome, asthma, and the pulmonary complications of sepsis (20). This role is manifested through both direct effects on lung physiology as well as through an indirect modulatory effect on the release of other mediators of lung injury, in particular profibrotic cytokines such as the interleukins and tumor necrosis factor (15). Recently, exaggerated eicosanoid production by both the alveolar macrophage (AM) and the type II epithelial cell has been demonstrated to result from the exposure of these cells to several particulates, including crystalline silica (quartz) dust (5, 9, 17). These observations have led to the suggestion that eicosanoids play a major role in the etiology of pneumoconioses.Another secretory component of the pulmonary environment, surfactant, has been shown to modulate crucial AM functions, such as bactericidal activity and the recruitment of circulating immune cells (25). Indeed, an important feature of the lung's reaction to inhaled mineral dust is an increase in surfactant production, perhaps as a compensatory or protective response (1, 16). In addition, the alteration of the surface properties of mineral dust by surfactant or its components has been shown to influence the biochemical response of the AM to the dust, perhaps by altering the surface charge of the dust particle (11, 29, 32). And recently, Wallace et al. (28) have shown that the coating of mineral dust with surfactant, and its subsequent removal by lysosomal phospholipase, unmasks differences in dust cytotoxicity that are not apparent when AM are exposed to uncoated dust. Thus it appears that the inclusion of surfactant in in vitro exposure studies may be important in evaluating both the absolute levels of eicosanoid production by the normal and dust-exposed AM and the temporal relationship between dust exposure and the production of inflammatory mediators by the AM. Therefore, we characterized the effects of the surfactants dipalmitoyl lecithin (DPL; the primary lipid component of natural surfactant) and Survanta (a commercially available surfactant derived from bovine lung) on basal and silica-induced AM eicosanoid production during two 24-h periods after exposure to dust particles to both allow the enzymatic removal of surfactant from the particle surface and evaluate the k"

Dec 1, 1996

By H. Tomlinson

Fatalities from falls of roof and coal are responsible for the death of more than 1,000 miners annually in the bituminous coal mines of the United States, or practically one-half of the total fatalities in and about these mines. The men are killed by falls singly or in small groups and little or no publicity is given these accidents as they lack the spectacular features of gas and dust explosions. As a result, the public and even the miners have the impression that accidents from falls of roof and coal are just one of the unavoidable hazards of the coal-mining industry. This belief is not true. Accidents caused by falls can be avoided largely by the application of sound engineering principles, by education, and by proper leadership in the industry, just as gas and dust explosions and accidents caused by explosives have been reduced in recent years.

Jan 1, 1933

By H. Tomlinson

Fatalities from falls of roof and coal are responsible for the death Of more than 1,000 miners annually in the bituminous coal mines of the United States, or practically one-half of the total fatalities In and about these mines. The men are killed by falls singly or in small groups and little or no publicity is given these accidents as they lack the spectacular features of gas and dust explosions. As a result, the public and even the miners have the impression that accidents from falls of roof and coal are just one of the unavoidable hazards of the coal-mining industry. This belief is not true. Accidents caused by falls can be avoided largely by the application of sound engineering principles, by education, and by proper leadership in the industry, just as gas and dust explosions and accidents caused by explosives have been reduced in recent years. The necessity for studying falls of roof and coal becomes apparent by referring to the following data from a table by Adams and Chenoweth:3

Jan 1, 1933

By J. E. Tiffany, Gaigler. Z. C.

"PREFACEIn presenting this list of permissible explosives and blasting devices, the Bureau of Mines desires to call attention to pages 16 and 21 outlining the conditions in use under which, and only under which, the explosive or blasting device is permissible.In view of a recent publication recounting trade practice favoring the use of a blasting device without stemming, particular emphasis is placed upon condition 4 on page 16 and condition 2 on page 21. An explosive or a blasting device enumerated in the permissible lists of this Bureau is not permissible in use unless it is properly confined with clay or other incombustible stemming.PERMISSIBLE EXPLOSIVES TESTED UNDER SCHEDULE 17CAn active list of permissible explosives was published in December 1937 as part of Bureau of Mines Report of Investigations 3361, under the title ""Active List of Permissible Explosives and Blasting Devices Approved Prior to June 30, 1937.n This list included 196 brand names.Changes in the list that have been authorized to June 30, 1938, placed 7 additional brands of permissible explosives on the active permissible list as a result of tests, changes in brand names, or transfer from the inactive list. Twelve permissible explosives were transferred from the active to the inactive list. The present list contains 191 brand names. The brand names of the permissible explosives placed on the active list are as follows:"

Oct 1, 1938