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By R. S. Dean

This report, the third of a series of annual reports of the Metallurgical Division to be released in this form, covers the fiscal year July 1, 1936, to June 30, 1937. The technological work of the division is performed by sections. Thus, an efficient organization is provided to prosecute the various problems under investigation, and a logical system is set up for presenting the material contained in this report.

Jan 1, 1937

By John J. Mulligan

Since 1941 the Federal Bureau of Mines has been conducting an intermit-tent program of placer and lode investigations to evaluate the potential tin resources of the western Seward Peninsula tin belt. Previous investigations were made in the Potato, Cape, Brooks (Lost River), and Ear Mountain areas. As part of this program the Bureau made a reconnaissance of reportedly tin-bearing stream gravels in areas adjacent to the previously worked tin deposits at Lost River and Potato Mountain. The objective of the reconnaissance was to determine if additional areas might be favorable for lode or placer exploration. The work was begun late in the fall of 1956 and completed during the following summer. The streams sampled were the Lost River and York Creek in the Brooks Mountain area and the Anikovik River and Kigezruk and Baituk Creeks in the York area. Samples were obtained by churn-drilling methods employing conventional placer-evaluation procedures. Holes were drilled at wide intervals at sites chosen as being representative of drainage areas rather than of individual gravel deposits. Minor to trace amounts of tin were found in the gravels of all these streams, but the highest grade was 0.35 pound of tin per cubic yard in the gravels of Lost River below the mouth of Tin Creek. Small amounts of gold were found on Baituk Creek and in one hole on the Anikovik River; the highest grade did not exceed 10 cents per cubic yard. Traces of scheelite and barite were found on York Creek, chromite was encountered in one hole on the Anikovik River, and minor amounts of titanium minerals (probably derived from basaltic intrusives) were found in the York area.

Jan 1, 1959

By Thomas P. Mucho

Retreat or pillar recovery mining redistributes the overburden weight onto the adjacent coal pillars in a room-and-pillar section. The additional stress and the resultant energy stored in the remaining pillars can become so great that pillars may bump or violently fail. An investigation at the Gary No.2 Mine was conducted to examine the effectiveness of the thin pillar mining method for mitigating bump occurrences. Field observations were made and instruments were installed to monitor pillar behavior during extraction. Stress monitoring instruments and roof-to-floor convergence stations were installed in pillars and entries and crosscuts, respectively. Results indicated that high pillar stress concentrations occurred in these bump-prone geologic conditions. The thin pillar mechanism, the creation and progressive outby movement of an expanded yield zone, was also monitored through the instruments. The expanded yield zone, a result of using thin pillars in a highly stressed pillar line area, mitigates bump risk.

Jan 1, 2010

By B. W. Naugle

A small-scale laboratory coke oven similar to those described by Swiniarski, Cryan, and Altieri and Fuchs, Sandhoff, Taylor, and Gauger was built by the Bureau of Mines in 1943. Tests made since that time have indicated that such a small oven is of questionable value in predicting the coking pressures to be expected in commercial coke ovens. This summary of the work done has been prepared at the suggestion of the Advisory Committee to the Bureau of Mines-American Gas Association Survey of Carbonizing Prop¬erties of American Coals.

Jan 1, 1948

By G. A. Savanick

The Bureau of Mines has designed, fabricated, and field tested a water jet cutting device capable of perforating nonmetallic well casings for the purpose of completing or stimulating in situ uranium leaching wells. The device is lowered into the wellbore, where it issues a high-velocity water jet that penetrates either a polyvinyl chloride or fiberglass casing, cement, and from 1 to 4 feet into the surrounding uraniferous sandstone. The resulting perforations allow leaching solution to pass between the sandstone and the wellbore. This report describes the water jet perforator, tells how it is used, presents cost data, and discusses the results of laboratory and field tests. The tests were designed to (1) determine the optimum operating conditions for water jet perforation, (2) assess the effects of changes in these conditions, (3) evaluate the performance of the water jet perforator under actual conditions, and (4) compare this method with other methods of well completion. These tests showed that water jet perforation is superior to conventional well completion methods for selectively achieving communication between the well-bore and adjacent sand while maintaining sand control, for restoring permeability lost through wellbore damage, for stimulating poorly performing wells for completing wells with casings that have inside diameters as small as 2 inches, and for extending the effective well diameter.

Jan 1, 1981

By Timothy Y. Yen

This Bureau of Mines report evaluates audio dosimeters, 3 sample units from each of 10 currently marketed brands. Each dosimeter was treated as a "black box" with the acoustic stimulus as the input and the accumulated dosage as the output. The dosimeter microphones were exposed to a sound field gener¬ated in an anechoic chamber. Characteristics evaluated include frequency response (100 to 8,000 Hz), level-time trade-off rate (88 to 117 db), status of calibration, crest-handling capability, and power consumption rate. Experi¬mental errors revealed by replication of the tests were found to be generally much smaller than variations in performance among the samples of any brand, and possibilities of further reducing the magnitude of these errors are discussed.

Jan 1, 1977

By D. Harrington

The record of fatalities from mine explosions in the United States during the past 3 years has been the best in the history of the mining industry. During these 3 fiscal years, mine explosions have resulted in an average of 4I0 deaths per year, as compared with an average of 153 deaths per year for the preceding; 5 years; an average of 542 deaths per year for the 3-year period 1907-09, inclusive, just before the organization of the U. S. Bureau of Mines; and a yearly average of 265 deaths per year for the 20-year period prior to 1929. This remarkable reduction in deaths from mine explosions demonstrates clearly that mine explosions can be controlled; in fact, they can be prevented when or if the mining people of the United States see fit to take the readily available precautions necessary to bring about this desirable objective. Several large coal-producing States, which in the past have had numerous disastrous explosions, have been free from such disasters for continuous periods of as much as 6 years or even longer. The bituminous mines of Pennsylvania, the largest coal-producing State, give a good example of what can be done to prevent explosions; this State has had only one major explosion (and it resulted in 7 fatalities) during the past 6 years, and no explosion occurred in the several hundred bituminous-coal mines of the State during the past fiscal year. This is a truly remarkable record when compared with past performance in any year in the operation of coal mines in Pennsylvania.

Jan 1, 1936

By Harold J. Bennett

The purpose of this study was to develop methods for the financial evaluation of mineral deposits. This includes the selection of the best alternative mining and processing methods and production rates. This was done by performing a financial evaluation through computer simulation using sensitivity and probabilistic risk analysis. The criterion used to measure the relative advantages of these investment and operating alternatives is the discounted-cash-flow rate of return. Included is a description of the theory and methods used in the probabilistic analysis approach, which is based on the premise that the expression of a range of values in establishing an estimate for a parameter is more realistic than the choice of a single value. Numerous simulations are made using randomly selected values of the input parameters resulting in a frequency distribution of the rates of return and their relative probability of occurrence. The sensitivity analysis method is described and combined with the probabilistic analysis to interrelate mineral reserves, capital investments, operating costs, and production rates. The ability to vary these input parameters on successive runs has permitted the selection of the best alternative mining and processing methods and production rates for a given mineral deposit. For illustrative purposes the evaluation of a mineral deposit was performed using three alternative mining and processing methods at three different quantities of resources and various production rates and prices. The computer program used in this analysis was written in FORTRAN II for maximum compatability and should run without modification on most computers having BK (8,000-word) core memory, a card reader, and printer (120 characters per line).

Jan 1, 1970

By J. A. Herdlick

The Star mine, near Neihart, Cascade County, Mont., has been in continuous operation since the construction of a 50-ton bulk flotation mill in 1939. The mine was examined by G. N. Bennett, an engineer of the Bureau of Mines, in November 1942. At that time the life of the operation appeared to be limited and a program of crosscutting and core drilling were recommended. The program had as its objective the investigation of a promising undeveloped area lying west of the Star vein and, if possible, the development of enough reserves in this area to insure continuous operation during the war emergency. Development of additional reserves would then justify necessary changes in the mill in order to eliminate the heavy penalties imposed for excess zinc in the bulk concentrates. The Bureau of Mines work began in February 1944 and was completed in September 1944. The project was started by Wilder R. Brinton and continued by Thomas W. Oster, mining engineers in the Bureau's Montana district office. Beneficiation tests on are and concentrates were made after completion of the underground work. This report presents the factual data obtained during all phases of the Bureau's investigation.

Jan 1, 1949

By R. S. Dean

The work of the metallurgical fundamentals section during the past year, representing active experimental investigation or thermodynamic study, may be summarized as the following problem subjects: 1. Low-temperature specific-heat investigations. 2. Development of a method of concentrating gases. 3. Thermodynamic properties of metallic carbides and nitrides, 4. Production of pure chromium from chromium chlorides. 5. Thermodynamic properties of the hydrates of calcium, sulphate. While this list is not identical, with officially designated problems, due to overlapping of subjects and to new developments within specified problems, presentation upon the basis of this subdivision will best serve to review the work of the section.

Jan 1, 1937

By Will H. Coghill, Fred D. DeVaney

"INTRODUCTION The Mesabi iron district of Minnesota has a potential production of over 50 million tons of iron ore annually. The large shipments of ore each year are gradually depleting the reserves, and if the present rate of production is to be maintained there must be a growth in the present available ore supply.Growth is a natural course. The growth of a city may be affected by the addition of city blocks or by the improvement of utilities necessary for its betterment, these may go on in the order named or concurrently. The city-block type of growth of the Mesabi has been tremendous, and the ""betterment"" type has followed in due course. Probably the former has reached its limit, and if so, more time will be allotted to the latter. It is not the intent of this paper to present either a eulogy of the wonderful mining methods or a history of the milling, but it is pertinent to say that if the lean-ore area continues to produce, the continuance will be more the result of further improvement of milling methods now well under way than of extension of boundaries by the city block plan of growth.In an examination of the western end of the Mesabi district one finds sludge basins containing millions of tons of millable ore rejected by washing plants which were built for economy in operating cost and with little thought of conservation, and rich tailings piles of jigging plant rejects. In addition, there is an appreciable tonnage of bawl rake pro-ducts so low-grade that it requires mixing with the best ore of the district to make it merchantable.Any of these three products is a source of additional reserves, but gangue must be removed before the products will comply with blast-furnace stipulations. All investigators are agreed that to effect this separation comminution must be fine enough for liberation, but beyond this point opinions diverge; some would seek new processes, while others adhere to methods and machines developed in other mining districts.In the investigation by the Mississippi Valley Experiment Station of the United States Bureau of Mines working in conjunction with the Missouri School of Mines and Metallurgy,Rolla, Mo., the latter course has been followed. Attention was first given to the sludge basins mentioned. From their contents good grades of concentrates were made and the results published 4 later commercial-scale tests were made in a pilot plant of 10 tables, and the laboratory results were confirmed, The tailings from jigging plants are high in iron, and a study of their possible retreatment showed that if they are recrushed, high recoveries of acceptable grade may be expected. The results will be published later."

Apr 1, 1932

By Glenn L. Cook

Correlations between mass spectra and molecular structures of 186 organic sulfur compounds are discussed. The olefinic ions, the alkyl ions, the CnE2n+1 ions, the m/e 61 ions, and the m/e 35 ions in the spectra of thiols are related to molecular structure. In the spectra of sulfides, the olefinic ions, the m/e 61 ions, the m/e 35 ions, the CnH2n+1S+ ions, and the CnH2n+1SH+ ions are correlated with molecular structure. For disu1fides, the correlations relate HSSF+& and RSSH+ ions to molecular structure. Base peaks of alkylthiophenes are correlated to their molecular structures. Some unimolecular reactions of sulfur compounds in the mass spectrometer are considered. A cyclic intermediate is suggested for the reaction which produces m/e 47, CH3S+, and m/e 48, CH4S+, ions in the spectra of sulfides. An expanded ring is suggested as a possible intermediate in the reactions of thiophenes. Heats of formation of sulfur-containing ions and their appearance potentials are presented in tabular form. Ionization potentials for sulfur-containing radicals and molecules are also given. Discussion of the spectra, tabulated in the appendixes, provides an insight into the relationship of the molecular structure of a compound to the mass-to-charge ratios and the intensities of the ions in its mass spectrum. Correlations of the mass spectra with molecular structures are empirically developed by observing regularities in the spectra of the reference compounds. Correlations extend the usefulness of mass spectra because they can be employed to determine the molecular structure of an unknown compound.

Jan 1, 1965

By Robert J. Hundhausen, Robert M. Gammell

"INTRODUCTION Several mining properties in the Pine Creek area of the Coeur d'Alene mining region of Idaho were examined by engineers 3/ of the Bureau of Mines in 1942. As a result, a broad program of exploration was recommended for the area, particularly in the eastern end, where chances for the discovery of new ore shoots seemed favorable. This report describes the work done and the factual information obtained by the Bureau of lanes.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 Be Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch,. C. C. Ralston, chief, analyzes samples and performs beneficiation tests.The exploratory work at the Sidney mine was part of the activities of the Albany Division of the Mining Branch, S. H. Lorain, chief. Field work was under the direction of R. M. Gammell.Chemical analyses included in this report were performed at Reno, Nov., under the direction of A. C. Rice, acting engineer in charge, Rare and Precious Metals Experiment Station, Bureau of Mines. The ore-dressing tests were made under the direction of S. R. Zimmerley at the Bureau of Mines laboratory in Salt Lake City, Utah.The cooperation and assistance given by the owners of the Sidney Mining Co. is gratefully acknowledged."

Feb 1, 1948

By Thomas J. Peters

In 1987, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied the 15,174-acre Sleeping Giant study area, including the 6,112-acre Wilderness Study Area (MT-075-111), in order to evaluate its identified mineral resources. The study area is located in Lewis and Clark County, MT, about 30 miles north of Helena. Sleeping Giant Mountain trends west-northwest from the Missouri to the eastern crest of Little Prickly Pear Canyon (the route of Interstate 15), and has several summits over 6,000 ft. Geologically, the area is in the Disturbed Belt, and a large block of Middle Precambrian metasedimentary siltstone and underlying shale has been thrust northeast over younger, sedimentdry volcanic and intrusive rocks.

Jan 1, 1988

By H. D. Bemis

This paper describing the milling practice of the American Metal Co. at its Pecos con¬centrator is one of a series on milling methods and costs being prepared by the United States Bureau of Mines. ACKNOWLEDGMENT The author acknowledges the assistance rendered by Guy Martin, metallurgist, H. E. Brown and J. H. Hastings, chemists, and Thomas J. Fahey, accountant, in gathering and pre¬paring the data presented in this paper.

Jan 1, 1932

By James J. Dowd

The investigation to evaluate the reserves of coking coal in the United States suitable for the manufacture of metallurgical coke is being made by the Bureau of Mines in three parts: (1) To estimate known measured and indicated recoverable reserves of all coking coal; (2) to upgrade marginal coals through effective preparation; and (3) to study the carbonizing properties of coals and coal blends not now widely used for metallurgical coke making. This is the eighth of a series of reports giving the results of studies by counties under part (1) of the investigation. (See appendix.) This report covers Jefferson County, Pa., which comprises parts of Marienville, Hallton, Ridgway, Brookville, DuBois, Penfield, Smicksburg, and Punxsutawney quadrangles. (See fig. 1.) A short resume of the chemical and carbonizing properties of the coals is included. Data on the coal beds in the county were obtained from mining companies, land companies, individual landowners, and other sources of authentic information. A base map for each bed in each quadrangle was made to the scale 1 inch equals 1,200 feet. Maps of mines, locations of drill holes, bed and total coal thicknesses, and the outcrop of the bed were plotted on the maps. With all available data plotted, isopach lines were drawn to limit areas of known unmined reserves in beds 0 to 14 inches thick, 14 to 28 inches thick, 28 to 42 inches thick, and over 42 inches thick, These areas of coal reserves also were divided into "measured" and "indicated" categories. All areas in each thickness range and in each category, mined-out areas, areas excluded from the estimate, and areas outside of the outcrop were measured by planimeter on the base maps. Estimates of total reserves 14 inches and more thick and maps for individual beds were prepared from these data.

Jan 1, 1952

By W. P. Yana, J. B. Littlefield

"INTRODUCTION AND OBJECT OF EXPERIMENTAn explosion in and rupture of a gas-tight switch box on an electric loader in a mine located near Pittsburgh indicated that the cause was an internally generated inflammable gas-air mixture. This led to the suspicion that moisture condensation or ""other unusual conditions might have caused a spark or are across the surface of the material and that the heat may have created a carbonized path across the synthetic plastic base which would then conduct a large current with the generation of considerable heat and thermal decomposition of the base materials base in the box which exploded gave every indication that this series of events had taken place, and accordingly it was desired to determine what explosive gases such a decomposition of these insulating materials would produce.ACKNOWNLEDGMENTSThe desirability of making this investigation was suggested to the authors by L. O. Ilsley, supervising engineer, electrical section, Bureau of Mines, to whom the occurrence of an explosion in a switch box had been reported. The writers also acknowledge with thanks the assistance of L. B. Berger, chief scientific aide, health laboratory section, Bureau of Mines, in checking the calculations in the tables. DESCRIPTION OF MATERIAL INVESTIGATEDThe ten materials used in the tests, identified by letters A to J inclusive, are described in a succeeding list of materials. All the materials except I had a phenolic odor, especially when freshly cut."

Dec 1, 1932

By WILLIAM F. McMURRAY, James O. Lewis

The Bureau of Mines is investigating the technology of petroleum and its products, the investigation including well-drilling methods and the transportation, treatment, and utilization of petroleum and of natural gas, with especial reference to the prevention of waste and to increased efficiencyin the development of oil and gas resources in land belonging to or controlled by the Government. During. the winter of 1912-13 the enormous waste of the gas encountered while drilling for oil in the Cushing field, Oklahoma, called forth protests from various sources, and appeal was made to the President of the United States and to the Secretary of the Interior in behalf of the landowner and of the public in general. The facts were wanted regarding the amount of waste and the technical conditions that were responsible for practices causing it. An investigation was ordered and conducted under the direct supervision of the late J. A. Holmes, the first Director of the Bureau of Mines. R. S.Blatchley was sent to investigate the amount of waste going on in the Mid-Continent flelds.s In the latter part of March, 1913, J. A. Pollard and A. G. Heggem were sent to Oklahoma to study well-drilling methods with reference to the waste of gas from wells on Indian lands and to suggest means of preventing the waste of natural gas on such lands. Pollard and Heggem decided that the mud-laden fluid process, which had been used successfully for some years in Texas, Louisiana, and California was the method that would meet the situation most efficiently and economically. The method was accordingly demonstrated in Oklahoma. In 1914 Congress provided for the employment of six oil and gas inspectors to supervise oil and gas mining operations on lands of the Five Civilized Tribes in Oklahoma and to conduct investigations with a view to the prevention of waste. Positions under this appropriation have been held by William F. McMurray, James O. Lewis, Harry D. Aggers, Ralph R. "Weed,George W. McPherson, James C. Fowler, Louis W. Courtney, and Carl H. Beal, the technical work of these men being directed "byW. A. Williams, chief of the petroleum division, Bureau of Mines. After careful and impartial investigation of conditions in Oklahoma, these men also decided that the mud-laden fluid process was the one best adapted to prevent further wastes. In 1915 laws were passed by the State of Oklahoma that provide for the conservation of natural gas and oil, authority being given to the corporation commission to make rules and regulations and to employ agents to enforce them. After hearings and investigations, the corporation commission reached substantially the same conclusions as the Federal agents regarding the importance of the wastes and the best methods of conserving the gas. Technical Papers 66a and 68b were published by the Bureau of Mines in December, 1913, and January, 1914, respectively. Technical Paper 66 deals with the mud-laden fluid process in general and No. 68 with its application in Oklahoma. The interest aroused by these publications has been so widespread that within two years the first editions have been practically exhausted. Rather than reprint these publications, it has been considered advisable to replace them with the present report, which includes the results of more recent investigations. The methods of using the mud-laden fluid are an outgrowth of the rotary drilling system, which was developed in Texas and later employed in Louisiana and California. Some of the principles of the use of mud fluid had been observed and used to a limited extent for a long time in cable-tool drilling. So far as known it was first used successfully with a circulator and cable tools in the Coalinga field, California, in 1906,Harry D. Aggers, one of the contributors to this paper, working on the well. The part of the Bureau of Mines has been to call attention to its merits and to demonstrate its practical use in fields like those of the Mid-Continent.

Jan 1, 1916

By E. L. Garton

An active list of permissible explosives was published in July, 1931, as part of United States Bureau of Mines Report of Investigations 3134, under the title of "Active List of Permissible Explosives and Blasting Devices Approved Prior to June 30, 1931." Changes in that list were authorized in August, September, October, November, and December, 1931, and January and March, 1932, as published in Reports of Investigations 3140, 3147, 3150, 3155, 3158, 3161, and 3163, respectively. By these changes the following explosives were added to the active Permissible list: Austin Red Diamond No. 1, L. F. Gel-Coalite W, L. F;" Austin Red Diamond No: 5. Gen-Gel No. 2. Black Diamond Nu-Gel No. 1 Genite C-1 Burton 1, L. F. Liberty No 4 Burton 2, L. F. Liberty No. 5 Burton 10, L. F. Peerless D Burton 12, L. F. Permigel 1, L. F. Burton F, L. F.

Jan 1, 1932

By Wallace W. Key

Mineral raw materials produced in California, other States, and foreign countries were purchased for consumption in quantities valued at over $60 million at 800 of the 1,200 chemical plants operating in California in 1960, according to questionnaires completed by company officials. These and other data received from mineral consumers, producers, dealers, and Government agencies formed the basis for this the first of a series of reports designed to present the intricate features and relationships controlling mineral raw material supply and demand in California industries. The results of this study indicated certain changes in use patterns of minerals in chemica 1 manufacturing; a shift in requirements from metals to nonmeta ls, from inorganics to organics, from natura 1 to synthet ic materia ls , and from distant to local sources of supply.

Jan 1, 1965