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By N. A. Tolch

[In this partner ?propulsive strength? or "strength" is defined as the relative propulsive effect of an explosive as determined by means of the United States Bureau of Mines ballistic pendulum. The data presented are derived from one particular strength testing device and do not necessarily represent the relative execution value of the different explosives in actual blasting. However, it is believed that the data obtained with the ballistic pendulum fire indicative of the relative propulsive or heaving force and are of value until propulsive strength can be expressed in more fundamental units.]

Jan 1, 1929

By L. B. Pankratz

High-temperature heat contents were measured for two praseodymium oxides and three terbium oxides. There were: Pr2O3 (298° to 1,600° K), PrO1.833 (298° to 1,050° K), Tb2O3 (298° to 1,600° K), TbO1.719 (298° to 880° K), and TbO1.812 (298° to 850° K). With the exception of PrOl.833, all results were regular. PrO1.833 had a small thermal anomaly at 760° K with an extra absorption of 380 cal/mole. The measured heat content values, tabulated smooth heat contents, and entropy increments are reported. Heat content equations were derived.

Jan 1, 1966

By R. J. Hundhausen

The continued worldwide shortage and strategic value of nickel place great importance upon the continued development and exploitation of new sources of nickel in the United States, The deposits of nickel-bearing minerals in Oregon and Washington have attracted considerable attention, particularly since the Hanna Development Co. has engaged in development work aimed at producing ferronickel from the Nickel Mountain deposit, near Riddle, Douglas County, Greg. The Red Flats nickel deposit in Curry County, Oreg., was first examined by the Bureau of Mines in dune 1945, but it was not until 1952 that the deposit was drilled and sampled. In 1953, a 15-ton sample of Red Flats material was procured and subjected to continuous smelting tests in the Bureau's Northwest Electrodevelopment Laboratory, Albany, Greg.

Jan 1, 1954

Develop a more efficient method of testing the integrity of in-situ leach mining operations. The Problems For economic and environ-mental reasons, in-situ leaching operations must be sure that wells do not leak. Loss of solution in large quantities can be expensive in itself, and if such losses result in pollution the costs can be even higher. Wells are usually tested for leaks by sealing them with packers, pressurizing them and monitoring the pressure drop. However, many commercially-available packers are designed to be used in steel-cased wells rather than the fiberglass-or plastic-cased wells used for in-situ mining. These packers are heavy, cumbersome, expensive, and often leak. In addition, commonly used well-integrity-test systems require lengthy test periods and drill rigs or hoist trucks with rigid pipes must be used to run the packers in and out of the well. The Bureau of Mines has developed a mobile, self-contained leak-testing system that is faster, uses trailer-mounted equipment that can be operated by one person, and features a new inflatable packer.

Jan 1, 1985

By P. M. Brown

The Bureau of Mines is investigating a dewatering technique for coal-clay waste that uses a flocculant, polyethylene oxide (PEO). This flocculant forms strong stable flocs that can be dewatered on a static screen. A field test unit (FTU) using this technique was operated at approximately 400 gal/min, using a waste stream from the flotation circuit of a coal preparation plant. Consolidated coal-clay material con-taining 55 to 60 pct solids was produced when the flotation circuit slurries of 2.7 to 8 pct solids were treated with 0.1 to 0.3 Ib PEO per ton of solids. The FTU was also operated at 64.5 and 87.5 gal/min using a portion of the underflow slurry from the preparation plant's thickener. Consolidated coal-clay material containing 55 to 60 pct solids was produced when the thickener underflow slurries of 19 to 24 pct solids were treated with 0.08 to 0.2 Ib PEO per ton of solids. PED-treated materials continued to dewater when placed in a pit.

Jan 1, 1983

By B. W. Naugle

Twenty-nine sole-heated-oven expansion teats were made on 9 different coals, and apparent specific-Brevity tests were made on 12 of the resultant cokes. The coals, which ranged in dry, mineral-matter-free fixed-carbon content from 58.7 to 81.1 percent, were tested over a rather wide range of moisture content and dry-coal bulk density to determine the separate effects of these variables on linear coal expansion. The experimental data support the follow expression relating "as-tested" coal bulk density, moisture content, and linear expansion, [ER = (1-MR) (1+Et) - 1; BDt] where ER = fractional expansion at a reference bulk density of 55.0 lb. of 1 percent moisture coal per cu. ft., Et = fractional expansion at Mt and BDt, MR = reference moisture content = 0.01, Mt = moisture content, "as-tested", BDR = reference bulk density = 55.0 lb. per cu, ft., BDt = bulk density, "as-tested", 1b. per cu. ft.

Jan 1, 1957

By Edmund S. Leaver

The Precious Metals Section is concerned primarily with ore-testing problems associated with precious metals and with the analysis and concentration of a large number of the strategic-mineral samples that have been included in the research program of the Bureau of Mines. During the fiscal year 1938-39, 30 projects were completed. The requests for this service are based upon the desire of the sponsor to obtain the best or most satisfactory method for maximum recovery of the minerals. In many instances it is a question of improving present milling practice, with due regard to utilization of present equipment. In others, the probable tonnage available maybe the deciding factor in the choice of a particular recovery method. Under all circumstances the results of tests axe prepared with the thought of aiding a competent metallurgist, familiar with local conditions, to formulate a practical flow sheet or to assist the mill operator to correct known losses. A microscopic examination for identification of the mineral constituents and their association in each ore is always a big help, in planning the tests and may indicate the reason for former troubles or assist with best procedure.

Jan 1, 1940

By Edmund S. Leaver

The Precious Metals Section is concerned primarily with ore-testing problems associated with precious metals and with the analysis and concentration of a large number of the strategic-mineral samples that have been included in the research program of the Bureau of Mines. During the fiscal year 1938-39, 30 projects were completed. The requests for this service are based upon the desire f the sponsor to obtain the best or most satisfactory method for maximum recovery of the minerals. In many instances it is a question of improving present milling practice, with due regard to utilization of present equipment. In others, the probable tonnage available maybe the deciding factor in the choice of a particular recovery method. Under all circumstances the results of tests axe prepared with the thought of aiding a competent metallurgist, familiar with local conditions, to formulate a practical flow sheet or to assist the mill operator to correct known losses. A microscopic examination for identification of the mineral constituents and their association in each ore is always a big help, in planning the tests and may indicate the reason for former troubles or assist with best procedure.

Jan 1, 1940

By Carl Belser

This report is the first of a series dealing with the oil-shale reserves of the Green River formation in the Rocky Mountain Region. The known oil-shale reserves of northwestern Colorado at present considered to have economic value apparently are confined to the Piceanco Creek basin between the Colorado and White Rivers. The number of sampled sections is small, but there can be little doubt that the Piceance Creek basin is a potential source of enormous quantities of liquid fuels and the related byproducts obtained from oil-shale processing. The partly blocked and inferred oil-shale reserves of 25-gallon-a-ton shale are estimated to have an oil yield of 125 billion barrels and the reserves of 15-gallon-a-ton shale are estimated to have an oil yield of 494 billion barrels. The number of available sampled sections is inadequate for making firm estimates.

Jan 1, 1951

By S. J. Pearce

There are a number of methods for determining relatively small quantities of sulfur dioxide in air. However, those methods require fairly elaborate apparatus and laboratory facilities. Frequently in industrial hygiene surveys it is desirable to have a simple arrangement to obtain "on the spot" determinations. This has been accomplished for concentrations of sulfur dioxide of hygienic significance by using the midget impinger and decolorizing a starch-iodine solution.

Jan 1, 1948

By H. A. Doerner

Tellurium is a silver white solid with metallic luster, the e17atal.line torm being ver., brittle aud e.g,s!ly powdered. It has a specific gravity of 6,27, melta at 45a0c. and boils at red het, giving off a. golden 1ellow vapor when air 11 excludei. When heated in air, telluri'UiD burns with a bl\te name tinged with green, and evolves wh1 te vapors ot tellurium dioxide. An amorphous form of tel­lurium, obtained by red.uction and precipi ta.tion from so).ution, haa II specific gr1.vity ot 6,015, and when heated ia cho.nged to the cry:.,talline variety. Telluri,a 11 insoluble in water, c&rbon diaiJ.phido, or h;rd.rochl oric acids, but it 11 41a-1olved bJ nitric or concen t1·ated. sulphi.U·ic acid. It 1..oea not tamiah in moiet ah•• 11 ree11tant to alkaline solutions, e,;:ctpt concentrated KOB, but it 11 cliaaolvecl by tuaed. &lkl 1••. I ts 11.to!!lic weight h..'l.a been the "J.Ubject ot mch controverq, bu\ t.he value 137 .5 :.a bl!ten generally accepted, Tho chflmietr:, of tellurium ia eim1lar to that ot IUlphur. It tonne throo xid.ee TeO, To02, and Te0 , al10 tellur14ea, t•llurite,, and. tellur1.t11, A number of halide compoWld.1, a 3iulph1de, and. a .ulpbat.e are known.

Aug 1, 1922

By Thomas J. Peters

During the 1982 Bureau of Mines study, 55 lode and 17 placer claims were held in the RARE II area. An estimated 150 lode claims and 50 placer claim, have been located in the study area; five were patented. There are no mineral leases. Gold has been produced from 8 lode mines and stream gravels have been worked for placer gold at 4 sites. Two suction dredges were active in stream gravels, but no significant gravel bars are identified. Identified mineral resources in the Weaver Bally area are gold and byproduct silver. The identified resources are at the Globe Mine, where approximately 33,000 tons of indicated marginal reserves (2,000 tons in the RARE II area, and 31,000 tons in the adjacent proposed Trinity Alps Wilderness) contain 0.45 oz gold per ton and probably 0.1 oz silver per ton. There are an additional 150,000 tons of inferred marginal reserves (35,000 tons in the RARE II area, and 115,000 tons in the adjacent proposed wilderness) averaging 0.38 oz gold per ton and probably 0.1 oz silver per ton. There is high potential for additional resources at the Globe Mine.

Jan 1, 1983

By Kenneth J. Miller

Laboratory batch flotation tests were conducted to determine the viability of the Bureau of Mines coal-pyrite flotation process in desulfurizing various coals from the midwestern coalfields. Nine coals obtained from western Kentucky and Illinois were used in the study. In addition to the Bureau's coal-pyrite flotation process, some of the coals were subjected to two-stage rougher-cleaner coal flotation for comparison. The results of this work showed that up to a 70-percent pyritic sulfur reduction could be obtained by flotation and that the Bureau's coal-pyrite flotation was superior to rougher-cleaner coal flotation. Because many of the coals retained far too much sulfur even after second-stage flotation treatment, it was concluded that these midwestern coals are more difficult to desulfurize by flotation than are the Appalachian coals tested in earlier Bureau experiments.

Jan 1, 1978

By W. W. Adams, V. E. Wrenn

"Production of explosives in the United States during the calendar year 1935 decreased 2 percent from 1934, according to reports covering all companies engaged in the manufacture of explosives during those years.Reports from manufacturers showed a total production of 308,381,250 pounds of explosives; this quantity included 39,170,016 pounds of permissible explosives 5/ 200,323,559 pounds of high explosives other than permissibles, and 68,887,675 pounds of black blasting powder of which 34,222,625 pounds were granular powder and 34,665,050 pounds pellet powder.Coal mines consumed 89 percent of the total production of blasting powder, 99 percent of the total output of permissible explosives, and 11 percent of the output of other high explosives.The metal mines of the United States used 28 percent of all high explosives other than permissloles, less than 1 percent of all permissibles, and 1 percent of all black powder produced.Quarries and nonmetallic-mineral mines consumed 17 percent of the high explosives other than pormissibles, less than 1 percent of the permissible., and 3 percent of the blasting powder.Construction work required the largest quantity, 40 percent of all high explosives manufactured during the year. Less than 1 percent of the permissibles and 6 percent of the black powder produced during 1935 was used in construction work."

Nov 1, 1936

By G. W. Jones

In the course of experiments on the stabilization of acetylene gas by addition of other gases, notably hydrocarbons such as methane, propane, and butane, it was observed that large quantities of carbon black are produced during the explosion of acetylene or mixtures of acetylene with the, above hydrocarbons, the added hydrocarbon being essentially decomposed into hydrogen and carbon. It is known that in the complete absence of air acetylene explodes upon application of an intense ignition source at pressure above 5.9 p.s.i. gage. The same is true of mixtures of hydrocarbons and acetylene. However, the pressures necessary for explosion are considerably higher in the case of these mixtures and depend on the amount of added hydrocarbon. The present report contains data on gaseous products and the physical characteristics of the carbon black formed by explosion at elevated pressures of various mixtures of acetylene and hydrocarbons as well as other gases, such as hydrogen, helium, nitrogen, and carbon dioxide.

Jan 1, 1950

By S. W. Zoldok

[The Bull Valley iron-ore district lie,; in the northern part of Washington County, Utah, approximately 30 airline miles southwest of the highly productive Iron Springs area (fig. 1). Iron-ore occurrences in the district have been known for many years, but they have not been mined, largely because of the inaccessibility of the area. The Bureau of Mines established a development project in the Bull Valley district in September 1941. Two separate areas, the Pilot and the Cove Mountain, were investigated. The work was planned to increase iron-ore reserves for steel production in the Western United States. During the project period three diamond-drill holes aggregating 1, 000 feet were completed (fig. 2). The program also included 6 408 linear feet of surface trenching and 171 feet of underground work (figs. 2 to 8, inclusive). Analyses were made of 460 samples from the diamond-drill holes and surface and underground excavations. The results of the analyses are given in tables 1, 2, 4, and 5, and the logs of the diamond-drill holes are shown in table 3. Field. work was completed in September 1942.]

Jan 1, 1953

By J. H. Hild

The Shanton magnetite-ilmenite deposits lie on the east flank of the Laramie Mountains, 43 miles northeast of Laramie, Albany County, Wyo. (fig. 1). The Shanton and other similar deposits in the Laramie Mountains were examined by Bureau of Mines engineers during 1942, 1943, and 1945, and a report2/ describing the results of a dip-needle survey and surface sampling was published in 1946. The Shanton deposits occur in a relatively flat section of the range at altitudes varying from 7,500 to 1,650 feet (fig. la). Prevailing rocks in the Shanton area consist of anorthosite with intrusive dikes of gabbro differentiates and granite. Titaniferous magnetite outcrops in five masses, which are separated at the surface by overburden and anorthosite.

Jan 1, 1953

By Sidney Katell

This Bureau of Mines study estimates typical capital investments, operating costs, and selling prices for two bituminous coal strip mines in the Eastern and Interior provinces and a subbituminous coal operation in the Northern Great Plains province. The annual productions were based on tonnage required to fuel a 250-MM-scfd, high-Btu gas plant. The annual tonnage for the Eastern province mine is 4.8 million tons; for the Interior province mine, 6.72 mi 11 ion tons; and for the Northern Great Plains province mine, 9.2 million tons. It is assumed that the mines have a 20-year life. Wages and union welfare payments are considered as of May 12, 1974, under the terms of the Bituminous Wage Agreement of 1971, and costs for material and equipment are based on 1973 and early 1974 indexes . Initial capital investment varies: $45,358,600 for the 4.8-million- ton-per-year (MM tpy) mine in the Eastern province, $54,603,000 for the 6.72 MM tpy mine in the Interior province, and $29,871,000 for the 9.2 MM tpy mine in the Northern Great Plains province. Total capital invest-ments for the Eastern province mine, the Interior province mine, and the Northern Great Plains province mine are $61,070,000, $76,753,000, and $56,286,000, respectively. Corresponding selling prices for the coal, per ton, are $4.79, $4.23, and $2.66, assuming a 12-percent discounted cash flow rate of return after Federal income taxes. These studies are considered typical for the areas involved. Costs will vary depending on specific locations in these areas.

Jan 1, 1974

By D. J. Parker

This report is based on data collected in and about the Liberty mine of the Liberty Fuel Co. by D. J. Parker and W. W. Kessler on December 13 and 14, 1933. An important phase of an examination to determine the general condition of a mine with respect to safety is the collection of dust samples from rock- dusted areas. Definite conclusions, based on intelligent interpretation of the analyses of such samples, can be reached only when the general condition of the mine is known. A similar examination and report were made on this property in January 1930 by D. J. Parker and R. I. C. Manning. Since that time much has been done by the management to improve safety conditions in this mine. The changes made will be noted in the course of this report. The mine is in Spring Canyon at Latuda, Carbon County, Utah, and is served by a branch line of the Denver & Rio Grande Western Railroad about 7 miles long and connecting to the main line near Helper, Utah. The writer desires to express his sincere appreciation for the many courtesies and helpful cooperation extended by Superintendent George Schultz and Mine Foreman F. W. Koelling.

Nov 1, 1934

By R. D. Govier

The U.S. Bureau of Mines has developed a thin-film X-ray fluorescence technique to rapidly determine Cu, Ni, Co, Fe, and Cr in super alloy leach liquors. Total analysis time per sample was less than 15 min, as opposed to several hours for traditional wet chemical methods. Precision and accuracy were checked by replicate analyses of solutions similar in composition to leach liquors, whose analyte concentrations were well known. Coefficients of variation for all elements were found to be less than 2 pet. With the exception of the results for Fe, all relative errors of estimation were also found to be less than 2 pet. Bulk liquids are not introduced into the spectrometer; thus, the potential for damage to the instrument by leakage of corrosive liquids is eliminated.

Jan 1, 1989