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By E. C. Lane

The motor gasoline that is being marketed in the United States this winter is practically the same 'as that sold a year ago. In fact, there has been little char sin this commodity during the year, as the gasoline sold last summer was almost as volatile as that marketed last winter. Boring the past eight years, the Bureau of Mine's has made semi-annual surveys of the gasoline marketed in the United States, the survey just completed being the fifteenth 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, 1927

By G. S. Price

This paper, which describes the milling practice at the Page concentrator of the Federal Mining and Smelting Co., is one of a series being prepared by the Bureau of Mines. The Page mine and mill are located on Silver Creek, 3 miles west of Kellogg, Idaho, and 1 mile south of United States Highway No. 10. Supplies and concentrates are hauled by truck over an automobile road which connects Highway No. 10 with the property. The concentrator has capacity to treat 300 tons of ore per day and utilizes all-flotation methods of treatment. Power is supplied from the main line of the Washington Water Power Co. which runs from Spokane, Wash., to Kellogg, Idaho. Water is obtained from the mine and also from a well which is situated 1 mile distant from the concentrator and about 600 feet in elevation below the concentrator.

Jan 1, 1932

Develop a simple and economical technique for determining the absolute stresses and the change of stress on the surface of roofs, floors, or walls in miners. Approach Use a commercially-available, permissible, Whittemore-type gage to determine the stress at the surface of a mine opening and to monitor any stress changes that might take place. How It Works The following equipment is used: ? One steel templet (for laying out a 60° rosette on the: rock surface). See first photograph. ? One 3/8-inch rock drill bit for drilling holes for the rosette pins. ? Six stainless-steel rosette pins. ? One Whittemore-type mechanical strain gage. ? One drill (not shown). ? Epoxy for cementing the rosette pins. ? Tape to hold the pins while the epoxy sets. The following procedure is used to determine the absolute stress on the rock surface. 1) Spot the location of the rosette pins with the templet. 2) Drill the pin holes and set the pins with epoxy cement. 3) Measure and record the distance between the pins across three diameters of the rosette with a 10-inch Whittemore-type gage. See diagram. 4) Drill a 1 1/2-inch diameter hole in the center of the

Jan 1, 1981

By W. R. Reed

Drilling with water has the potential to significantly reduce the respirable dust concentrations generated from small-diameter rotary drills when drilling blastholes on surface mining operations. However, water adverseky affects tri- cone drill bits commonly used in surface drilling operations, causing excessive wear and premature replacement. Consequently, dry drilling with a dust collector system has the most widespread use in the industry. Tests have been conducted by the National Institute of Occupational Safety and Health (NOSH), Pittsburgh Research Laboratory (PRL) on a newly designed device for smaller diameter drills that separates the water from the bailing air before it reaches the bit and thus provides the cost benefit of dry drilling while providing the benefit of wet drilling for dust suppression. The water that is delivered to the hole with the bailing air is separated from the air by a proprietary mechanical device that is encased in a drill sub (short section of drill rod/pipe) located immediately behind the cutting bit. A cascade cyclone and a real-time dust monitor were used to sample dust emissions from the holes. Dust concentrations and silica content were measured when drilling dry versus drilling wet. The tests show that drilling with this water separating sub can reduce both measured dust emissions from the boreholes and visible dust around the drill rig.

By Richard A. Winters

The 31,880-acre Battle Creek Wilderness Study Area (WSA) was evaluated for mineral resources by the U.S. Bureau of Mines in 1984. No mining district is in the area, nor were any mines or claims recorded or found. Oil and gas leases, or lease applications, covered about half the area in early 1984. No known exploration has occurred. The entire WSA is covered with thick volcanic flows. Faults in these volcanic rocks may have provided conduits for mineralizing solutions emanating from the basement rocks; however, no evidence of mineral deposits was detected from rock samples collected along the faults. Reconnaissance samples from sand and gravel deposits yielded gold at less than $0.02/yd3. The source of the gold is assumed to be intrusive rocks or the Challis Volcanics about 20 miles north of the study area near the headwaters of Battle Creek. No economic concentrations of minerals were found in the WSA. INTRODUCTION Mineral surveys of designated wilderness study areas (WSAs) 1/ are conducted by the U.S. Bureau of Mines (USBM) and the U.S. Geological Survey (USGS) at the request of the U.S. Bureau of Land Management (BLM). The USBM researches the mining and mineral exploration history and evaluates mines, prospects, and mineralized areas within or adjacent to WSAs. The USGS studies WSAs by regional geochemical and geophysical surveys and geological mapping. The USBM and the USGS investigations are summarized in a joint report used to help determine the suitability of WSAs for inclusion into the National Wilderness Preservation System. Although the immediate goal of this USBM study is to provide data for the President, Congress, BLM, and the general public for land-use decisions, the long-term objective is to help insure that the Nation has an adequate and dependable supply of minerals at reasonable cost.

Jan 1, 1985

By d&apos, Kathleen J. Amico

This summary appears in Minerals Yearbook volumes I-II, and III, which cover mineral production in the United States, its island possessions, the Canal Zone, and the Commonweath of Puerto Rico, as well as the principal minerals imported into and exported from the United States. The sections of this chapter and the area chapters in volume III contain further details on production. A summary table comparing world and U.S. mineral production also is included. Mineral production may be measured at any of several stages of extraction and processing. The stage of measurement used in the chapter is normally what is termed "mine output." It usually refers to minerals in the form in which they are first extracted from the ground, but customarily includes for some minerals the product of auxiliary processing operations at or near mines.

Jan 1, 1967

The Ringelmann Smoke Chart fulfills an important need in smoke abatement work and in certain problems in the combustion of fuels. A knowledge of its history and method of preparation is, therefore, of interest to many. Since instructions on its use are not shown on the recent edition of the chart, those included in this revision of the previous Bureau of Mines publication now are a necessary complement to the chart, More detail regarding the use of the chart is included than was given in the earlier version.

Jan 1, 1967

By Donald P. Mickelsen

The raining and quarrying trends data shown in this report were reported to the U.S. Bureau of Mines (USBM) by mining and quarrying companies on the Mine Information Supplement survey, as well as by mineral producers on 58 annual USBM production and consumption surveys covering 59 nonfuel mineral commodities. The 1993 data presented in the tables of this chapter, were processed for the first time using the USBM Automated Mineral Information System. Domestic mining of nonfuel mineral materials totaled 3.7 billion metric tons in 1993, including 2.2 billion tons of crude ore nun& or quarried and 1.5 billion tons of mine waste and ore from development. This \vas an overall increase of 11% over that of 1992. These data do not include construction sand and gravel which until 1993 has been surveyed biennially. Starting in 1994, construction sand and gravel and the stones, which were also surveyed biennially, will be surveyed annually.

Jan 1, 1993

By Edward L. McHugh, Charles Sabine, Louis J. Denes, Jami M. Girard, Peter Metes

The Spokane Research Laboratory, National Institute for Occupational Safety and Health, is investigating various remote sensing technologies as possible tools to detect, monitor, and mitigate hazardous situations in surface mines that could lead to catastrophic slope failure. Promising technologies include a field-portable spectro-polarimetric imager and a stationary interferometric radar device. Field tests were conducted of a prototype visible and near-infrared spectro-polarimetric imager (SPI) built at the Carnegie Mellon Research Institute. The SPI employs anacousto-optical tunable filter (AOTF) to control wavelength, a phase retarder to measure polarization signatures, and a digital camera and computer to capture data. Images obtained at the Mountain Pass and Castle Mountain mines in southeastern California showed that the instrument is capable of obtaining hyperspectral images of highwalls, outcrops, hand samples and drill core in the field. We have retrieved spectra from Mountain Pass images that closely match those of bastnaesite and have had some success in classifying images. Although radio frequency noise in the data limited spectral classification of imagery, we project that careful alignment of the AOTF should minimize the noise and greatly improve classification.

This surveillance report summarizes data on work-related fatal and nonfatal injuries, illnesses, and hazardous exposures in the mining industry for the 10-year period 1986-1995. The term ?surveillance,? as used in public health, may be new to many readers of this report. With regard to occupational safety and health, the goal of surveillance is to describe the occurrence of work-related injuries, illnesses, and known hazardous exposures; to identify new hazards that may occur due to the introduction of new technology or other factors; and to assess the effects of preventive measures designed to improve worker safety and health. Surveillance provides an overall picture, which can be used to focus resources on areas most in need of prevention programs or further research. Surveillance generally requires the use of multiple sources of data, all of which have their own strengths and limitations. Surveillance in the U.S. mining industry is complicated by the fact that U.S. national data systems that provide information on mining are based on two different definitions of the mining industry. One is established by the Mine Safety and Health Administration (MSHA), the other by the Standard Industrial Classification (SIC) System [Office of Management and Budget 1987] and the 1980 U.S. Bureau of the Census (BOC) Classification System [U.S. Bureau of the Census 1982].

Jan 1, 2000

By V. B. Dale

This paper is one of a Federal Bureau of Mines series covering the mineral resources of the Nation. It briefly describes most of the tungsten deposits in Cochise, Pima, and Santa Cruz Counties, Ariz. Most of the descriptions are from field examinations by the two senior writers, prior to July 1957. Wolframite first was identified in Arizona in 1896 by W. P. Blake, Territorial Geologist. Tungsten mining began about 1900 in the Little Dragoon deposits of Cochise County, and about 1901 in Las Guijas district of Pima County. The price history of tungsten is an erratic one; consequently, production has been erratic. Prices rise during wars and periods of national preparedness. Production of tungsten ore was stimulated greatly by a Government purchasing program, announced on May 10, 1951, wherein the Government agreed to purchase standard-grade tungsten concentrates at $63 per short ton unit5/ for 5 years or until 1,468,750 units were purchased. This was later increased to 3,000,000 units, and after this amount had been purchased in June 1956, the purchase of an additional 1,500,000 units was authorized. Government purchase, however, was suspended in December 1956 before completion of this latter program, and the price of tungsten concentrates declined sharply. The price had dropped to $15 per short ton unit, duty extra,6/ by the last part of July 1957.

Jan 1, 1960

By Eugene T. Sheridan

The 23d annual survey of the peat industry by the Bureau of Mines, United States Department of the Interior, revealed that 75 producers in 17 States re-ported commercial production of peat in 1956. Forty-seven producers reported humus production, 19 reported reed-sedge peat, 17 reported moss peat, and 1 reported muck. This total exceeds the number of active operations, but several producers reported recovering more than one type of peat. Fifty-five percent of the total production was reported as peat humus, 30 percent as reed-sedge peat, and 15 percent as moss peat. A negligible amount was reported as other types. More than one-fourth of the total output was raw peat with no preparation, other than having been air-dried. The remainder consisted of processed peat prepared for use by cultivation, shredding, or kiln drying.

Jan 1, 1958

By T. G. Carnahan

The Bureau of Mines investigated a flotation-nitric acid leach procedure as part of the goal to maximize minerals and metals recovered from primary and secondary domestic resources. Studies were conducted on an ore that contained carbon-bearing and sulfide mineralization that rendered a portion of the ore refractory (resistant) to conventional leaching technology. The procedure investigated for treating the ore consisted of the following: (1) separation by flotation of the carbonaceous and sulfidic components from the ore, (2) leaching the flotation concentrate with nitric acid at 100° to 110° C, (3) leaching the flotation tailings with sulfuric acid, and (4) processing the combined leached slurries in a conventional manner to recover yellow cake. In step 2, HN03 is converted to gaseous products from which it is regenerated by reacting these products with air and water for further leaching. An overall uranium extraction of 96 pct was achieved by this procedure.

Jan 1, 1979

By G. St John Perrott

"The United States Bureau of Mines is cooperating with the State of Utah and the City of Salt Lake in an investigation of methods of abating the smoke nuisance in Salt Lake City. In the course of this work samples of the atmosphere have been collected and analyzed in an attempt to determine the part played by sulphur dioxide or smelter gases in polluting the air at Salt Lake City.A fairly wide-spread opinion exists in Salt Lake City that the smelters contribute appreciably to the smoke nuisance. The gases discharged from the smelter stacks are believed (1) to float over the city in a heavy blanket which prevents the smoke from rising, and (2) to unite with the water vapor in the air to form corrosive fogs injurious to health and property.The first of these theories seems untenable. If the gas did not mix with air it would sink, owing to its heavier specific gravity, and form a blanket an the earth. Actually, the gas diffuses rapidly in air and any part reaching Salt Take must he thoroughly diluted. Perhaps sulphur dioxide in sufficient concentration might aid in fog formation. The more obvious nuisance, however, would be the injury to health and vegetation.The Garfield smelter is 16 miles west of the city, The Murray smelter 8 miles south, and the Midvale smelter 12 miles south. Under normal operating conditions, a relatively small amount of solid matter is discharged from these stacks. The toxic gaseous constituent of the discharge is sulphur dioxide, it is being discharged from the smelters the year round. If they are a factor in the city's smoke problem, the concentration of this gas in the air of the city should be appreciable and should increase toward the smelters, the con centration being highest with a south or a west wind."

May 1, 1920

By Brian G. White

Two examples of en echelon mining-induced fractures seen in hard-rock mines provided a basis for inferring that fracture zones and bedding plane separations immediately surrounding mine openings are promoted by oblique shear into the openings. It is hypothesized that initial fractures or separations form at the corners of openings as a result of high stress and physical constraint on the rock's ability to deform elastically toward the opening. These conditions result in a locally preferred direction of shearing. The shearing, in turn, generates tensile stress that initiates a progression of systematically offset fractures approximately parallel to the direction of greatest compressive stress. The fractures or bedding separations create tabular rock layers that amplify shearing displacement through bending and dilation. Such shearing effectively reduces and redistributes the compressive stress, but significant dilation is an inevitable consequence. The combination of dilation and shearing and the progressive development of fracture zones have important implications with respect to ground support. The concept of mining-induced fractures forming as a result of shear is illustrated by two examples from coal mines. First, fractures seen at longwall faces probably result from shear associated with subsidence. The fracture zone that develops approximates or possibly defines the draw angle of subsidence. As the face advances, fractures extend downward along the lower edge of the fracture zone, while upper extensions of the fractures are pressed closed. Fracture zones in entry roofs provide a second practical example. Here, mining-induced fractures typically follow bedding planes. The shear zone model suggests that the first bedding separations develop near the edges of the roof and successive separations progress upward and toward the center. However, if the direction of greatest stress is inclined with respect to the roof, a fracture or bedding separation zone may propagate from one side only and also extend higher. Because coal ahead of the face provides some support against lateral shear deformation, bedding separation is inhibited near the face. Rock bolts installed close to the face ultimately become more strained and bent than bolts installed a few meters from the face, and bolts installed through the more remote part of a separation zone may ultimately experience the greatest tensile and bending strains. This model is supported by field data documenting progressive bolt failures that rapidly propagated downward across the roof during face advance.

By W. E. Dennis

"INTRODUCTION The strategic importance of zinc warranted investigation of the Silver Eagle zinc prospect, which was first examined by an engineer 3/ of the Bureau of Mines in January 1943.From October 12, 1943, to March 16, 1944, the Bureau explored the deposit by trenching, core drilling, and sampling to establish the amount and grade of ore and to test for the presence of sulfide-ore minerals at depth.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director."

Oct 1, 1946

By John R. Shattuck

As a part of the general chromite investigation in California designed to aid In the production of chromite during the recent war emergency, the Bureau of Mines explored the Coggins property in Siskiyou County, Work by the Bureau in cooperation with the Federal Geological Survey began in October 1942 and was concluded in March 1943. This report presents a brief history of the mine, outlines the physical features of the district, describes the deposits) and explains the work completed by the Bureau of Mines, Table 1 shows the analysis of diamond drill-hole samples. The logs of drill holes are in the appendix.

Jan 1, 1949

By Oliver Bowles

From the most remote periods of civilization, stone Las been used to perpetuate the memory of individuals or to immortalize their noble achievements. Ancient memorials ranged from simple piles of stone (cairns) or single markers to great obelisks and pyramid or magnificent mausoleums. The Taj Mahal at Agra, India, built of white marble by Shah Jehan in memory of the Empress Mumtaz Mahal, is one of the most beautiful and costly memorials ever built. It was erected between 1632 and 1050 at a cost estimated at a: high as $50,000,000, and it is today an object of unusual attraction for travelers. Other magnificent memorials, both ancient and modern, are to be found in many lands. Memorials of varying design have characterized the passing centuries and have found an important place in the New World. In early days, monuments were chiefly imported into America, but gradually an extensive memorial stone-manufacturing industry developed on this side of the Atlantic. Sales value of domestic memorials, f.o.b. quarry or mill, attained a maximum of $17,488,755 in 1920, and retail sales, of course, reached a much higher figure. Modest markers and tombstones are to be found in almost every rural community in the United States, and there are many elaborate and costly monuments in and near urban centers.

Jan 1, 1938

By Wilbur Duvall

For the past few years the Applied Physics Branch has been investigating, experimentally, the generation and propagation of strain waves in rock. The strain waves are produced by the detonation of a high-velocity explosive placed in a small cavity in the rock. Strain gages mounted in the solid rock surrounding the cavity record the strain pulses propagated away from the source. Numerous strain-wave pulses have been recorded in different rock types for charges of various sizes and at various distances from the charge. Analysis of these records has shown, among other things, that there is associated with the strain wave a characteristic pulse width. This pulse width is dependent on the rock type and the distance from the shot point to the gage, but is apparently independent of the charge size or cavity size. Recent published literature on the generation and propagation of seismic waves indicates that the characteristic frequency of an elastic wave generated by an explosion should be a function of the rock type and the size of the cavity created by the explosion. Also, internal friction in the rock would produce absorption of high-frequency components, which would cause continual change in the shape of the pulse propagated. As the experimental data did not verify the expected change in pulse shape with cavity size, a theoretical investigation of the vibrations associated with a spherical cavity in an elastic medium was undertaken.

Jan 1, 1950

Four actual coal mine waters were used in various phases of the research program. All were from the Sewickley Creek area In Westmoreland County, Pennsylvania. The BCR designations, site locations, and nature of the mine water samples are described briefly in the following paragraphs.

Jan 1, 1971