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By Jerry E. Olson

In 1984, the U.S. Bureau of Mines conducted a mineral survey of the Black Rock Desert Wilderness Study Area (WSA) (NV-020-620), which covers approximately 319,000 acres in Humboldt County, Nevada. About 90% of the WSA is underlain by Pleistocene desert playa sediments; the remainder is comprised of Jurassic-Triassic metamorphic rocks, a Cretaceous intrusive and Tertiary volcanic rocks. Most of the WSA is within a down-dropped fault block of the Basin and Range physiographic province. No mines or evidence of major exploration were identified within the WSA; but five claim blocks within or adjacent to the WSA and zones of anomalous character as defined by the Bureau of Land Management were examined. No mineral resources were identified, but anomalous gold, silver, and indicator element content of samples taken near Pinto Hot Springs indicate resources may exist. Lithium content of samples from near-surface sediments on the desert playa is too low for resources, out geologic conditions are favorable for higher concentrations at depth. Occurrences of zeolites are not considered to be of commercial interest. Approximately 27,000 acres are held under geothermal lease, and most of the WSA is of interest for oil and gas. No evaluation of these commodities was made by the Bureau of Mines

Jan 1, 1985

By Raymond L. Lowrie

Coal deposits in the Boulder-Weld County coalfield in Colorado are analyzed in relation to economic factors governing the growth, stability, and competitive potential of the coal industry. Recoverable reserves, estimated to be 571 million tons, are discussed in detail, particularly those in the Erie and Frederick Quadrangles. Geology of the coal measures, quantity and quality of water resources, and chemical and physical properties of the coal are described. Coal production factors, including mining techniques and equipment, labor requirements, transportation facilities and rates, and markets, are considered for coal's position in competition with alternate fuels. Growth of the fuels market, through increasing thermal-electric power generation in the Denver Metropolitan Area, will stimulate coal production in Colorado. Reserves of the contiguous Boulder-Weld coalfield, if mined in a sustained, year-round, high-tonnage operation, could be used to supply much of that fuel demand.

Jan 1, 1966

By P. G. Bennett

The Bureau of Mines developed a process using ion exchange to recover cobalt from spent copper leach solutions. A preliminary economic evaluation of the process indicated that about one-third of the capital cost was attributed to the total resin inventory, and one-third of the operating cost was required for reagents to remove iron from the ion-exchange eluates. An agitated Pachuca elution system was investigated in place of a fixed-bed elution system. The Pachuca system reduced the resin inventory by 27 pet when compared with the fixed-bed elution system. Processing fresh spent copper leach solution reduced the resin inventory by 20 pct and resin iron loading by 80 pct. Reagent requirements for removing iron from the eluates were decreased because less iron was extracted. The Pachuca system, along with processing fresh spent copper leach solution, reduced the total resin inventory by 47 pct. A revised cost evaluation of the cobalt recovery process was obtained to determine the effects of these process modifIcations. The estimated total capital cost for a plant processing 10,000 gpm of spent copper leach solution containing 26 ppm Co was $23.1 million. With credits for nickel, zinc, and copper byproducts, the estimated net operating cost was $5.10/lb of cobalt.

Jan 1, 1988

By Howard P. Hamlin, John W. Sweeney

Shales from 14 locations in Indiana were sampled , tested , and evaluated to determine feasibility of producing lightweight aggregates by rotary - kiln and sintering methods . Sampling procedures and the geology of the significant shale units are discussed . Preliminary testing was conducted in a muffle furnace , and continuous tests were made in a 16 - inch by 14 - foot rotary kiln . The aggregate weighed 37.0 to 47.2 pounds per cubic foot . Concrete cubes employing the aggregate were tested to determine the qualities of the concrete . Compressive strength of the concrete using seven bags of cement per cubic yard , after autoclave curing for 6 hours , ranged from 3,600 to 5,850 pounds per square inch . Four samples made suitable lightweight aggregate in the laboratory rotary kiln . Four samples tested by sintering methods made unsatisfactory aggregate .

Jan 1, 1965

By A. C. Johnson

This paper is one of a series being prepared by the Bureau of Mines on exploration, development, mining methods and costs at various mines in the United States. It describes such methods at the Lincoln tungsten mine of the Wah Chang Mining Corp., Lincoln County, Nev. The purpose of these reports is to promote development and conservation of our mineral resources by disseminating technologic information on mining methods, practices and costs. The Lincoln mine in Lincoln County, Nev., in the southeastern part of the [tate], was acquired by the Wah Chang Mining Corp., in April 1951. Mining methods and costs are of special interest at this property because of the low costs and good production record achieved through a well planned program of exploration, development, and exploitation. Operations were discontinued in July 1957 after the Federal Government suspended the tungsten purchase program.

Jan 1, 1959

By A. L. Engel

Production of chromite in California has been from many small, high-grade mines. The opening of the Purchase Depot at Grants Pass, Oreg., in 1951 has stimulated chromite mining in California, and a large number of properties are being reexamined as there is a possibility that some low-grade ores from many of these properties can be beneficiated to meet the purchasing schedule. The Bureau of Mines in its program of conservation is continuing ore-dressing tests on chromite ores to better evaluate their potential. This report is a compilation of preliminary concentration tests on samples from five different properties in California. The concentration tests were made on ores from the David mine, Butte County, the Seiad Creek mine, Siskiyou County, the High Plateau mine, Del Norte County, Bud's mine, Tuolumne County, and tailings from the Miller concentration plant in San Luis Obispo County, Calif., to determine the possibility of beneficiating these ores so that they will meet the specifications for the Government stockpile.

Jan 1, 1956

By E. L. Garton

Bureau of Mines routine crude-oil analyses of 88 samples from 60 fields are presented in this report. Similar analyses from other fields in California have been published in previous reports listed in the appendix, page 52. Yearly production of crude oil in California and the percentage of United States production represented by California production for 1948-54 are given in table 1. [ ] Analyses in this report are of samples from the fields listed in table 2, with production data for 1953, cumulative production through 1953, and year of discovery of each field. Information regarding the source and general characteristics of the samples is included in table 3 with a summary of analytical and computed data.

Jan 1, 1956

By Robert H. Mattes

The Lake Lynn Laboratory is a multipurpose mining research laboratory operated by the Bureau of Mines and located in Fairchance, Pa, It consists of both surface and underground facilities. The initial focus of the facility, scheduled for full operation in fall 1982, will be on the problems of fires and explosions in mines. The initial experimental explosion was fired on March 3, 1982. The intent of this document is to provide the reader with detailed information on the physical capabilities of the Lake Lynn Laboratory. Subsequent publications will focus on the capabilities of Lake Lynn as compared with those of other similar facilities worldwide, and a comparison of initial explosion test results realized at Lake Lynn and comparable results from the Bruceton Experimental Mines.

Jan 1, 1983

By Ernesto Villaescusa, Andres Brzovic

Rock masses of the primary copper ore at the El Teniente Mine are very competent and massive. The rock mass contains almost no open discontinuities. Nevertheless, there is a high frequency network of small discontinuities coupled with widely spaced faults. A data collection campaign designed to characterize the rock structure was recently implemented. The results show that conventional analysis in terms of discontinuity frequency does not predict differences between two studied sectors. However, when an empirical definition of a weak discontinuity is applied, appreciable differences between the two sectors appear in terms of discontinuity frequency and predicted in situ block size distributions. These differences are in accordance with actual observations at the mine site. Due to the geological features of the primary copper ore, rock mass classification schemes cannot be readily applied to characterize these rock masses.

Jan 5, 2007

By Irving Hartmann

As part of the continuing effort by the Bureau of Mines to promote mine safety, research work is being conducted at the Experimental coal mine, Bruceton, Pa., on the prevention of coal-mine explosions and on other mine-safety problems. The principal subjects studied during the past 2 years are briefly described in this paper. Although at present these problems are relevant particularly to the mine layout and to high-speed mining practices in numerous American coal mines, it is hoped that the findings will prove interesting and useful also to our European research colleagues. Some of the investigations treated here will be presented in greater detail in forthcoming Bureau of Mines reports. 1. UNDERGROUND STORAGE OF COAL CUTTINGS The seams in mist American bituminous-coal mines are undercut, shear-cut, or top-cut before blasting. The cuttings arc generally loaded out with the balance of the coal. However, in some mines it is not economical to load and remove cuttings from the mine. This applies especially if the cut section of the seam is of appreciably lower grade than the rest of the coal, or if the cut is made partly into an adjacent stratum that is high in incombustible content. In such mines the cuttings are sometimes stored in random heaps in rooms or other areas, along the ribs of mine entries, or in layers on the floor of rooms or entries.

Jan 1, 1956

By W. W. Adams

Lower accident rates were the outstanding feature. of the second annual sand and gravel safety competition conducted in 1930 by the United States Bureau of Mines in cooperation with the National Sand and Gravel Association. Both the frequency and, severity rates for accidents were greatly reduced as compared with those shown by the first year's contest, that for 1929. Three times as many plants were enrolled, and the number of man-hours of work represented wad more than doubled. Seventy-six sand-and-gravel plants, situated in 20 States, participated in the competition, as compared with 26 plants, located in 13 States, in the year before. The number of man-hours of employment, which indicated the amount of exposure to occupational hazards, was 4,915,592 an increase of more than 100 per cent over, the previous year's total of 2.259,572 hours. The frequents of accidents declined from 74.4 per million hours for all plants enrolled in the first year's contest to 42.7 per million man-hours for all plants enrolled in 1930. The accident-severity rate was reduced from 9.7 days of disability per thousand man-hours of exposure in 1929 to 5.9 days of disability per thousand man-hours of exposure in 1930.

Jan 1, 1931

By D. Harrington

We Americans pride ourselves that ours is the greatest, most advanced and most civilized nation in the world, yet statistics indicate that apparently we have little appreciation for the lives and limbs of the people whose efforts give us whatever greatness we possess. The latest available statistics indicate that the annual accident death rate per 100,000 of population is nearly 80 or far higher than that of any other country in the world except Chile; is more than double the rate in Hungary, Netherlands, Ireland, Belgium, Denmark, Italy, Germany, Norway, Sweden, and Finland; is nearly double that of England, Wales, the Union of South Africa, New Zealand, Japan, Australia, and Scotland; and is 25 to 40 percent greater than Switzerland, France and Canada. To make matters worse, from the viewpoint of mining; the latest available statistics give mining by all adds the worst accident rate of the major industrial occupations in the United States, the accident severity rate for mining in 1935 being listed by the National Safety Council as 10.14, the next highest rate being 4.52 for construction, and the average rate for 30 main industries being 1.58. IMPROVEMENT IN SAFETY RECORDS Offsetting to a slight extent this rather dark picture is the fact that starting about 1930 the mine-accident rate in both coal and metal mining began to fall, reaching an all-time "low" in metal mining in 1932 and in coal mining in 1933. It now appears probable that the year 1936 has again lowered the accident rate in coal mining and this, together with the fact that the years 1933, 1934, 193 5, and 1936 all set much lover accident rates in coal mining than ware achieved for any similar previous period, gives hope that the trend is definitely in the right direction, though from the above figures mine-accident severity has a long, tedious road to travel before it becomes as low as the severity rate of all other major industries in the United States.

Jan 1, 1937

By G. S. Baur, J. W. Montoya, S. R. Wilson

Beryllium occurs in the Honeycomb Hills area in volcanic tuff similar to the more extensive berylliferous tuff occurring 20 miles east at Spor Mountain , Juab County , Utah . Samples from the two areas have been mineralogically examined to ascertain whether they have similar characteristics . The Honeycomb Hills samples showed the presence of beta- Be ( OH ) 2 , as well as an amorphous berylliferous substance , whereas in the Spor Mountain tuff the beryllium- bearing minerals are hydrated bertrandite and berylliferous saponite .

Jan 1, 1964

By W. Hermanson

This report, which covers the period from January 16 to October 21, 1974, describes the work performed in compliance with the requirements of contract no. H0242028 and modifications 1 and 2 thereto. The purpose of the contract was to further reline and modify three of the canopies (shuttle car, loader, and roof drill) which were developed under contract no. H0220031, and to conduct further testing and demonstration of the relined designs. Modifications I and 2 involved conducting further in-mine evaluations of the face. drill and cutter canopies, also developed under contract no. H0220031. In addition to the canopy modifications, the contract involved an evaluation of an operator's seat concept for a shuttle car which was developed for the USBM by another contractor.

Jan 1, 1974

By Samuel S. M. Chan

The objective of this project was to collect information applicable to the design of ground support systems in deep mines to include in-situ rock deformations, deformation-modulus, stresses, and geology and laboratory physical properties. All data collected was to be integrated and evaluated using a finite-elements computer code. In addition, considerable professional "cross pollenization" was anticipated from the association of University and SMRC personnel. Scope of Investigation Before a ground supporting system can be evaluated, the loading conditions existing in the region of investigation, strength, deformation characteristics, as well as other engineering properties of the rock structure immediately surrounding the openings, together with the pertinent geological information, must be obtained and analyzed. It was for this reason the following items were included in this research project: (1) The selection of a suitable area for the investigation. (2) The mapping of the important geological features of the area of investigation. (3) The measurement of in-situ deformation of rock masses immediately surrounding an underground opening of the area of investigation. (4) The determination of ground stresses. (5) The obtaining of in-situ modulus of deformation of the rock masses. (6) The testing of useful engineering properties of

Jan 1, 1972

By George H. Holmes

This paper is one of a series on mining methods and practices published by the Bureau of Mines. It describes quarrying methods and crushing practices of the U. S. Lime. Products Corp. at its Sloan and Apex quarries. Calcining and milling processes. at the Sloan and Henderson plants also are outlined. The Sloan dolomite and limestone quarries and plant are in secs. 12 and 13, T. 23 5., R. 60 E., and sec. 18, T. 23 S., R. 61 E., M.D.B. &M., Clark County, Nev., about. 17 miles by paved highway southwest of Las Vegas (fig. 1). The Apox limestone quarry, and crushing plant are in sec. 26, T. 18 S., R. 63 E., M.D.B.&M., Clark County, Nov., approximately 18 milos northeast of Las Vegas, adjacent to U. S. Highway 91 (fig. 1). The Henderson calcining plant is Inc., in sec. 13, T. 22 S., R. 62 E., 14 miles southeast of Las Vegas on U. in a reduction unit of Basic Magnesium, M.D.B. &M., Clark County, Nev., about S. Highway 93 (fig. 1).

Sep 1, 1949

By B. D. Sartwell

The formation of alloyed regions near the surface of metals using ion implantation is being investigated by the Bureau of Mines as a means of providing corrosion resistance using much smaller amounts of the strategic alloying metals. Two ion implantation systems that can implant low-energy chromium, nickel, or aluminum ions into low-cost substrate materials such as iron or carbon steel have been designed and constructed. The development of the ion source, ion beam acceleration stage, mass analysis system, and target chamber are described in detail. The ion-implanted alloys have been characterized using proton-induced x-ray emission to give the total number of atoms implanted and to determine the extent of any surface contamination introduced by the ion implantation process. Research conducted at other laboratories on metallurgical applications of ion implantation is given.

Jan 1, 1980

By Victor E. Kral

"SUMMARYA preliminary examination of the Buena Vista iron deposit was made in June 1942 by Paul E. Pesonen, mining engineer of the Bureau of Mines. Subsequent examinations were made by D. W. Butner, of the Bureau, in March 1943, and by the author in July 1944, who recommended exploration by diamond drilling, trenching, and sampling. Work on the project was done during the period March 28 to May 26, 1945.Property holdings, comprising 16 claims known as the Buena Vista group, are situated in sec. 4, T. 24 N., R. 34 E., Mount Diablo base and meridian, north Churchill County, about 37 miles east of Lovelock, Nev.Three diamond-drill holes totaling 575 feet were drilled; 45 small pits and ten trenches, totaling 435 linear feet, were excavated, and 84 channel samples totaling 862 feet were obtained under supervision of the Bureau.Purpose of the project was to determine the possible downward extension of the mineralized sections exposed in the outcrops and to determine grade of the ore.Bureau work was confined to one claim only - the Iron Mountain."

Jun 1, 1947

By J. I. Paige

The effect of fluoride inclusions on the properties of titanium produced from the Bureau of Mines developed induction slag melting process is of concern to members of the titanium industry. The objective of the research was to determine the effect of CaF2 inclusions on the properties of titanium and its survival rate during melting. The data were obtained from single induction-slag-melted ingots prepared with the normal addition of 4 pct and also with 2- and 1-pct additions of CaF2 slag. The results of this effort showed that the mechanical properties of single-induction-slag-melted Ti-6Al-4V alloy exceed the minimum values specified in Aerospace Materials Specification for Titanium Alloy Bars and Forgings AMS4928H, but these materials are much more notch sensitive in fatigue than normal Ti-6A1-4V alloy titanium. First and second vacuum-arc remelts of single-induction-slag-melted ingots fragmented and increased the number of inclusions, while reductions in the amount of flux resulted in an upward trend in the spatial distance between pores in an x-y plane.

Jan 1, 1988

By F. N. Kissell, C. H. Elder, C. M. McCulloch

The applicability of the "direct method" for determining the methane content of virgin coalbeds was tested. Preliminary results indicate that the direct method, when applied to exploration cores, can be successfully used to estimate coalbed gas content and also approximately predict the total gas emission from a prospective mine located in the coalbed at the exploration site.

Jan 1, 1973