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By E. C. Lane

The motor gasoline that is being marketed in the United States this winter is in general, more volatile than that sold a year ago. This increase in volatility is shown by a lowering of the distillation temperatures, ranging from 2°F. at the average initial boiling point to 5°F. at the average end point. During the past eight and. one half years the Bureau of Mines has made semi-annual surveys of the gasoline marketed in the United States, the survey Just completed being the seventeenth 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. Samples were collected in Boston for the first time since 1919. It was believed advisable to include samples from that district in order to give a better balance to the survey for the country as a whole.

Jan 1, 1928

By Edward L. McHugh

The Thousand Lakes Wilderness has no known economically significant mineral resources. However, the geologic setting of the Wilderness indicates a potential for the discovery of geothermal resources. INTRODUCTION The Thousand Lakes Wilderness occupies 16,335 acres (6,611 ha) in eastern Shasta County, California. A mineral resource study of the area was authorized by the Wilderness Act of 1964 (Public Law 88-577). Mining records and published information were examined, and field investigations conducted in 1979. The Wilderness is about 50 miles (80 km) east of Redding and 12 miles (19 km) south of Burney, California. It lies in the Cascade Range of California. Relief is more than 3,000 feet (910 m); elevation is greatest at the summit of Crater Peak, 8,677 feet (2,645 m).

Jan 1, 1982

By E. A. Loria

The Bureau of Mines analyzed the effects of oxygen, nitrogen, and carbon on the tensile properties of electrorefined vanadium in terms of the Petch equation. The effects of the different impurities and grain sizes on the yield and flow stress between 2730 and 770 K were studied. For specimens of like composition, the values of the Petch parameters 01 and ky obtained by two different methods, extrapolation and grain size, were nearly the same. For high-purity electrorefined vanadium, the 01 value at 2730 K was 10,300 psi (5,150 psi shear). The 01 values for this metal at 1950 and 2730 K were lower by factors of 3 to 4 than for three less pure samples of commercial vanadium metal of equivalent grain size. Nitrogen was more effective than oxygen in increasing 01' the increase being about twice as much for the same impurity level. Carbon produced a slight increase in 01 up to 0.024 percent and then a gradual decrease in 01 to 0.11 percent, the maximum carbon content studied. The corresponding ky values followed the same trend in regard to oxygen and nitrogen additions, whereas the addition of carbon produced no variations at either temperature. Dislocations in vanadium are anchored by carbon, oxygen, and nitrogen with increasing firmness in that order. The high purity of electrorefined vanadium was confirmed by low yield stress and high ductility throughout the low temperature range. The metal also exhibited profuse twinning with high ductility at 1230 and 770 K. The effective surface energy for fracture, y, was found to lie between 3.3 and 3.6 x 1()4 erg cm-2?

Jan 1, 1966

By Daniel E. Sullivan

The recession of 1974 continued into 1975. Real gross national product (GNP), measured in 1972 dollars, declined significantly in the first quarter of 1975 but rose slightly in the second and increased sharply in the third quarter. Unemployment peaked during the second quarter and then declined slowly for the balance of the year. The inflation rate declined owing to reduced demand and smaller-than-1974 increases in energy and food prices early in the year. Recovery was clearly evident by yearend, though un-employment and inflation remained at high levels. Total output as measured by the GNP in current dollars rose 6.5% in 1975. Real GNP declined 2.0%, and inflation, as measured by the implicit price deflator, increased 8.7%. Real gross private domestic investment for residential structures declined 18.1% in 1975, which was a smaller rate of decrease than the 27% decline in 1974. Real State and local Government purchases increased 2.4%, and real personal consumption expenditures for services rose 1. 7 %. The Federal Reserve Board (FRB) index of industrial production declined 9.7%.

Jan 1, 1977

By E. P. Carman

This report is the 19th in a series summarizing Bureau of Mines research and technologic work on coal and related investigations. The first 17 reports covered fiscal years; however, the 18th report3/ covered the 18 months from July 1, 1952, to December 31, 1953, to permit the publication of this and subsequent reports on a calendar-year basis. Most of the material in this report relates to publications by Bureau authors issued during the reporting period. Some work is referred to on which the results have not yet been published or may not be published for security or other reasons. In a few instances publications are mentioned that were issued before the reporting period but were not included in previous reports. Further details on the published work described herein may be found in the publications cited in the footnotes. Research and technologic work on coal by the Bureau is directed toward developing and encouraging increased conservation of coal resources through safer and more efficient mining, preparation, and utilization. Significant advances were made during the year in these fields, particularly in coal-mine safety and in preparation and utilization of the various ranks of coals.

Jan 1, 1956

By Thomas M. Barczak

he stiffness characteristics of longwall shields were investigated in this Bureau of Mines study. Since longwall strata activity is characterized by roof-to-floor and face-to-waste displacements, a model with two degrees of freedom was used to describe the load-displacement relationship of the shield structure. The model considers the support as an elastic body and relates horizontal and vertical resultant forces acting on the support to associated displacements as a function of the stiffness of the support structure. Stiffness coefficients under full canopy and base contact configurations were determined by controlled displacement loading of longwall shields in the Bureau's Mine Roof Simulator (MRS). Three two-legged longwall shields of different manufacture were investigated. The stiffness characteristics of these shields were evaluated relative to two parameters, namely, shield height and setting pressure. The test results indicate a reduction in shield stiffness for increasing height. Setting pressure was found to have less of an effect on shield stiffness, producing only a slight increase in stiffness as setting pressure increased. Similar trends were observed for all three shields, indicating a similarity in stiffness characteristics for shields of the same basic configuration.

Jan 1, 1988

In the interest of safety ii: coal mining, the Bureau of Mines recommends: That all active underground coal mines, whether working or idle, have one or more fans in continuous operation. The capacity and installation shall be such that the entire mine workings are adequately ventilated at all times. Main fairs shall be located on the surface in fireproof housing offset from the line of any mine opening. The housing shall be provided with ample pressure-relief doors or other devices easily opened by the force of an explosion. The installation shall permit prompt reversal of air flow. For mines that liberate gas, the fan shall have at least two independent sources of rower immediately applicable. Ventilation of underground workings in coal mines is needed whether or not explosive gas is present. Natural ventilation is unreliable and often uncontrollable. Main fans should be on the surface; if they are in the mine, fire or explosion may make access difficult or dangerous and render the installation inoperative.

Jan 1, 1939

By W. E. Robinson

Sixty samples, selected from a 2,300-foot core of the Green River Formation in Colorado, were studied to ascertain differences in the structure of the organic material present in the oil shale samples. Emphasis was placed upon relating differences in the aromatic content of the insoluble kerogen and the alkane content of the extractable material obtained from the selected samples. The methods used in determining these differences consisted of fractionation of the soluble material, carbon and hydrogen analysis, volatile material determination, carbon residue determination, oxidation rate determination, and infrared analysis. In general, it was concluded that the organic material in this core does vary in chemical structure and that same of these variations resulted from factors related to depth of burial. Other observed changes in structure of the organic material were not depth-dependent and resulted from other factors such as source material variations, biological alterations, or ecological differences.

Jan 1, 1971

By William O. Vanderburg

This paper describing the practice at the Wolf Pongee concentrator at Federland, Colo., is one of a series on similar subjects being published by the United States Bureau of Mines. The author acknowledges the assistance of Loach, manager of the Wolf Tongue Mining Co., and of W. G. Roseborough, superintendent of the golf Tongue mill, in the preparation of this paper.

Jan 1, 1933

By W. W. Simpson

During cyanidation of mercury-bearing gold-silver ores, significant amounts of mercury are extracted. The presence of mercury decreases. gold loading and increases mercury stripping time on activated carbon, complicates fire refining of the gold cathodes, and creates a potential health hazard. Addition of calcium sulfide (CaS) to the cyanide leach slurry precipitates the solubilized mercury but also some silver. The Bureau of Mines investigated silver loss during CaS precipitation of mercury. Addition of 0.1 lb CaS per short ton ore to a mercury-bearing gold-silver ore precipitated both mercury and silver. However, if copper was added with CaS, or if the ore contained copper, much of the sil-ver loss was prevented. Addition of 235 ppm Cu with 0.1 lb/st CaS, prior to carbon-in-pulp adsorption, resulted in 89-to 97-pct, 80-to 91-pct, and O-pct adsorption of the solubilized gold, silver, and mer-cury, respectively, on the activated carbon.

Jan 1, 1986

By Gustav Wade

"INTRODUCTION Analyses of samples of crude oil from several Texas oil fields have been published from time to time in Bureau of Mines reports, some of which are out of print, but many other analyses of Texas crude oils have not been published. The purpose of this paper is to make available in condensed tabular form under one cover all analyses of the Texas crude oils that have been examined by the Bureau of Mines.DIVISION OF TABLEThe table of analyses is divided into six parts in accordance with the geographic subdivisions of the State. (See fig. 1.) This grouping of the oils corresponds only in a general way with the principal formations in each area from which oil is being produced. In general, the principal oil-producing formations in the Texas Panhandle and West Texas areas are of Permian age; those of North Texas are of Pennsylvanian and older ages; those of the East Texas Basin and of Central Texas are of Cretaceous age; and those of the Texas Gulf Coast are of Eocene and younger ages.For convenience in presentation the name of the geologic age has been assigned to each group of the table although same of the oils included in the group may be of another age.Group 1 includes oils of Permian age produced in the Texas Panhandle area, which comprises the following counties: Dallam, Sherman, Hansford, Ochiltree, Lipscomb, Hartley, Moore, Hutchinson, Roberts, Hemphill, Oldham, Potter, Carson, Gray, Wheeler, Deaf Smith, Randall, Armstrong, Donley, Collingsworth, Parmer, Castro, Swisher, Briscoe, Ball, and Childress."

Dec 1, 1934

By John D. Sullivan

The present article is one of a series which is being prepared by the Southwest Experiment Station of the United States Bureau of Mines in cooperation with the Department of Mining and Metallurgy, University of Arizona, Tucson, Ariz., of papers dealing with factors involved in the leaching of copper ores. A knowledge of the time required to dissolve the various copper minerals present in ores, as well as of the consumption of leaching reagents is very desirable, because with the decrease of the Nation's total tonnage of sulphide ores increasing attention is being given to the recovery of copper by leaching methods from low-grade disseminated ore containing both oxidized and sulphide minerals. As leaching has already been applied with success and profit, this study was undertaken to determine certain fundamental characteristics that are applicable to all ores suitable for leaching.

Jan 1, 1929

By Lucia Kuizon

In 1986 and 1987, at the request of the U.S. Forest Service, the U.S. Bureau of Mines studied the Diamond Peak area comprising 183,000 acres in the Challis and Targhee National Forests in order to evaluate its identified mineral resources. More than 3,000 mining claims were located in three mining districts between the years 1882 and 1986. Approximately 230 mining claims in and the 150 claims adjacent to the study area were current in 1986, when Bureau of Land Management mining records were researched for this study. A total of 1,270 samples were collected from these sites (30 were for alluvial placer). Results of the investigation help determine the suitability of the study area for inclusion into the National Wilderness Preservation System. Lead-, silver-, zinc-, copper-, and gold-bearing minerals occur as veins and replacement bodies in shear and fault zones in Precambrian and Paleozoic calcareous Sedimentary rocks that have been complexly folded and faulted. Total production from the three mining districts in the study area was more than 150,000 tons of ore between 1901 and 1982. Approximately 11,600 tons of subeconomic resources consisting of lead, silver, zinc and copper were identified within the area. Over 37,500 tons of lead and zinc subeconomic resources were identified just outside the area. In addition, lead-, silver-, and zinc-mineral resources were identified at 4 mines within 2 miles of the study area. Iron mineral resources were also identified just outside the area.

Jan 1, 1991

By W. E. Wallace, P. S. Raghootama, M. S. Seehra, C. A. Hill, M. J. Keane, P. Mike

"Dipalmitoyl glycerophosphorylcholine (lecithin) dispersed in physiologic saline, a model of the primary component of pulmonary surfactant, is adsorbed by respirable quartz and aluminosilicate dusts. Dust cytotoxicity as measured by erythrocyte hemolysis and pulmonary macrophage enzyme release is suppressed by this adsorption. The degree of suppression of hemolytic potential versus specific adsorption of lecithin from dispersion in saline by respirable quartz, kaolin, and alumina dusts are compared with dusts' BET specific surface areas to interpret the prophylactic effect cf lecithin adsorption. Dust hemolytic potential versus media pH are presented. Fourier transform infrared spectroscopy and photoacoustic spectroscopy of lecithin on quartz and of lecithin on kaolin are presented and reviewed with results of studies of the time course of removal of lecithin adsorbed on mineral surfaces by digestion by phospholipase enzyme. Results are discussed in terms of a model of prompt neutralization of respired mineral dusts by pulmonary surfactant, and a gradual re-toxification by digestive processes acting on the adsorbed prophylactic surfactant coating following phagocytosis.Introduction Quarts dust of respirable size is well known to cause fibrotic lung disease, but numerous questions persist in the understanding of the initiation and' progression of this disease. Our approach concentrates on physical and chemical aspects of mineral dusts early-on in their interactions with living organisms, and we have chosen simplified models to investigate that interaction. In the alveolar spaces of the lung, tissue is coated with a surface-active material (pulmonary surfactant), which, sagas other functions, mechanically stabilises the lung from collapse by reducing the surface tension of water in the alveolar sacs.(1) This surfactant is also the material that is first contacted by a mineral particle that is transported to an alveolus and is impacted there. This surfactant material has been studied extensively. The primary components are known to be proteins (about 11% in dog lavage fluid). and phospholipids (about 88%).(2) Fhosphatidyl cholines constitute roughly 80% of the phospholipid fraction; about 70% of the phosphatidyl choline fraction is dipalaitoyl lecithin (DPL).(2) Respirable aluminosilicate particles are capable of adsorbing dipalmitoyl lecithin from dispersion in physiologic saline, a model for a possible initial event occuring upon deposition of a particle in a pulmonary alveolus.(3)"

Jan 1, 1988

By John W. Cole

The Bureau of Mines conducted a trenching and sampling project during 1947 on the tungsten-rich granodiorite that outcrops in Henderson Gulch, Montana. During the course of this investigation, interest was attracted to the Sunrise copper-gold mine in metamorphosed limestone in the north slope of the gulch. The mine was examined by S. H. Lorain, Chief, Mining Division, Albany Branch, in May 1948. A trenching and drilling program was recommended to develop a parallel vein indicated by outcrops to lie below the principal productive Queen vein. In the meantime, the Queen Mining Syndicate initiated a trenching program that exposed high-grade lead-copper-silver-gold ore in a nearly vertical vein that strikes N. 600 E. to east. A core-drilling program to develop this vein was initiated in September 1948. This report presents the factual data obtained from the trenching and drilling operations. The Sunrise mine was discovered about 1890. Production has been estimated to be $120,000 in gold from 40,000 tons of ore mined during the period 1892-1903. The tailing from this operation was treated by cyanidation in 1912, with a reported recovery of $3.50 to $4.00 a ton from 15,000 tons of material. Subsequent production of sulfide ore was 7,396 tons treated by smelting, with recovery of 1,569.42 ounces of gold, 10,003 ounces of silver, 352,899 pounds of copper, and 354 pounds of lead.

Jan 1, 1950

By Lisa Steiner, Robin Burgess-Limerick

In 2004, there were 646 underground coal mines in the USA employing 37,445 miners. These mines reported 3556 injuries to MSHA that year - 17% were associated with bolting machines (593 injuries), 8% with continuous miners (283 injuries), and 4% each with Scoop/LHD (1 51 injuries), shuttle cars (134 injuries), and personnel transport (145 injuries). The use of the frequency of reported injuries for the prioritization of risk control strategies has limitations because of the tendency to underestimate the importance of relatively rare but high-consequence events. Injury reports also underestimate the contribution of risk factors such as whole body vibration, which have a long-term cumulative contribution to an elevated risk of injury. However, taking these limitations into consideration, the results of the injury narrative analysis suggest the following hazards as the highest priority for elimination or control: • rock falling from supported roof • inadvertent or incorrect operation of bolting controls • handling continuous miner cable • collisions while driving LHD/Scoop, shuttle cars and personnel transport • rough road while driving or traveling in LHD/Scoop, SC & PT

By Barbara Fotta, Lynn Rethi

Within the Mine Safety and Health Administration's (MSHA's) classification of metallnonmetal (MAM) mining, the number of independent contractor' employees has increased significantly in recent years. In 1985 independent contractor employee hours reported to MSHA accounted for 4.5% of all M/NM mining employee hours (excluding office workers); by 1994 that proportion had doubled to 9.0%. As a result, these workers now account for an increasingly significant proportion of fatal and nonfatal mining accidents. According to MSHA's statistics, annually computed fatality incidence rates (the number of fatalities per 200,000 employee hours) for independent contractors working in M/NM mining are consistently higher than those for operator employees. Over the five-year period from 1990 through 1994, 53 independent contractor employees were fatally injured while working on M/NM mine property (See Table 1). More than one third of these fatalities (36%) were due to accidents involving powered haulage; 21% were machinery accidents; and 11% percent were falling material accidents. Combined, these three accident classifications accounted for 68% of all independent contractor fatalities occurring on M/NM mine property during these years. Clearly, current efforts to increase the safety of the mining workforce must also address the safety of the independent contractor employee. This report is a preliminary attempt to identify trends in the employment and safety of independent contractor workers by identifying which segments of M/NM mining are experiencing the greatest increases in the number of independent contractor employees and by examining changes in the rates and types of accidents in which these employees are involved. The employment and accident data used in this report were obtained from the MSHA database. [ ]

By Edward P. Barrett

[Iron oxides, when reduced at temperatures below 900° form a dark gray substance, very porous bait otherwise in almost the same form as the original particles. In the temperature ire range of 1,000 to 1,100° the product is pertly sintered but still shows the outlines of the original particles. Those products are known as "sponge iron." At temperatures of 1,100 to 1,2000 the metallic iron begins to flow together and to a semifused, pasty, porous mass called a "bloom," which can he worked under a hammer to form a product similar to wrought iron; it contains slag inclusions and is too low in carbon to make steel. If the temperature is 1,300 to 1,300°, part of the iron will fuse enough to absorb more carbon. The dissolved carbon lowers the melting point and still more carbon is absorbed. The melted portion acts a flux for the unmelted metallic particles until the entire mass becomes a high-carbon fluid known as "cast iron." Sponge iron was probably the form in which the first iron was recovered from the ores. As early as the eighth century the Catlan forge3 developed into a low-shaft furnace known as the "high bloomary," in which iron eras produced in the form of a pasty mass. In 1340 the first blast furnace was built in Belgium. The greater part of the iron was made into wrought-iron blooms by crude puddling processes. Charcoal was used as the fuel until tie latter part of the 17th century when coke was used in England. In 1865 Bessemer built his first converter in. England, and within a few years the Siemen's regenerative open-hearth furnace was developed, also in England. Enormous expansion in the metallurgy of iron followed. The idea of "direct processes" for the production of iron arid steel has persisted throughout all this time. The production of steel from sponge iron has theoretical advantages over the present-day standard methods, and handreds of so--called "direct processes" have been proposed or tried during the past century.4]

Jan 1, 1929

By Glenn C. Reed

This report is one of a series describing mineral investigations within the Missouri River Basin in Montana. The primary purposed of these investigations is to provide information to agencies of the Department of the Interior and others concerned with the planning of Federal power developments in the basin. This report is limited in score to consideration of mineral deposits of presumed inventory value within Gallatin County, Mont. The field investigations were made during the fall of 1948.

Jan 1, 1951

By A. J. Farstad

The current emphasis on energy needs in the United State sand abroad has placed an increased demand on the coal mining industry. The United States is fortunate to have abundant coal reserves. However, coal mining techniques and technology have not kept pace with the increased demand for coal. Consequently, coal mining in the United States continues to be one of the most hazardous industries. One of the daily hazards faced by coal miners is the sudden and unexpected occurrences of roof falls. The research program described in this final report focuses attention on the problems of unstable roof conditions in coal mines and describes prototype equipment which, with further development, has potential of being able to warn miners of impending roof falls in mines. Westinghouse Electric Corporation, Geophysical Instrumentation Systems Group was awarded a contract to develop and test a microseismic roof fall warning system based on general specifications derived from earlier Bureau of Mines research [1], [2]. During the first year of this two year effort (Contract H0242045) the electronic monitoring systems were de signed and built while the second year of the contract was devoted to equipment field testing in working coal mines.

Jan 1, 1976