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By Pedro Lilienfeld

This report describes a program whose objective was to develop, design, fabricate and laboratory-test two prototype instruments capable of real-time selective detection and measurement of airborne fibrous-shaped particles. The operation of this fibrous aerosol monitor (FAM) is based on the rotation imparted to the acicular particles by means of a rotating quadrupole electric field of the order of 3000 V/cm. This field induces a dipole charge separation on the fibers and aligns them with the applied field. The selective detection of the fibers is effected by synchronous detection of the resulting modulation of the light scattered from a continuous-wave helium-neon laser beam by the rotating particles. The theory of operation, design of the electric-optical detection configuration and the electronic signal processing method are discussed. By means of a scattering pulse sharpness discrimination technique, fibers whose length exceed a selectable value are detected and their number concentration digitally displayed. Counting times of 1 to 1000 minutes permit the measurement of fiber concentrations between 0.001 and about 30 cm-3. A concentration of the order of one fiber per cubic centimeter can be assessed within a relative standard deviation of 10 percent with a counting period of 10 minutes. The FAM is a portable, battery-powered instrument capable of operating continuously for about 4 hours between battery charges. Preliminary tests with crocidolite and crysotile asbestos as well as with glass fibers were performed in the laboratory and the results indicate good correlation with the standard NIOSH phase contrast microscopy filter counting method.

Jan 1, 1977

By A. A. Cochran

The purpose of this Bureau of Mines research was to investigate the theoretical and practical aspects of using ionizing radiation to promote chemical reactions that are of interest to metallurgists, and to carry out a radiation study of a suitable reaction. The effect of 44,000 roentgens per hour of 120,000-volt X-rays on the chlorination of highly pure mixtures of rutile, carbon, and various catalysts at temperatures up to 540° C. is described. At these low temperatures, recoveries were very low; however, in the eight different systems studied, an increase in yield due to X-rays was statistically significant in two instances and was of borderline significance in a third instance. In the other five systems, the differences in yield were not significant. Impurities and added catalysts caused relatively large variations in the yield of TiC14 from the reaction. Although the catalysts employed were reported in the literature as positive catalysts for the reaction, most of them were negative catalysts for the highly pure system studied. With only one exception, each increase in the purity of the charge resulted in a decreased yield of TiCl4. The experimental results indicate that many substances catalyze the reaction studied and suggest that the differences in reactivity of the charge stocks may be due to their various contents of positive and negative catalysts.

Jan 1, 1962

By David Schlain

The Bureau of Mines investigated methods for electrodepositing platinum-group metals from molten cyanide baths. The preparation of thick, protective coatings on molybdenum, Inconel, graphite, stainless steel, copper, and other structural metals were studied, as well as the electroforming of platinum and iridium crucibles. Iridium, rhodium, and ruthenium can be electrodeposited under an inert atmosphere, while platinum and palladium require the presence of air. Electrolytes may be prepared by direct-current electrolysis in NaCN or mixtures of NaCN and KCN using anodes of the particular platinum-group metal. When the concentration of metal increases to about 0.3 or 0.4 percent, the deposits become bright, adherent, and coherent. Current densities may be 10 to 25 ma/cm2, and plating rates are often 0.5 mil/hr. Platinum and palladium baths deteriorate because of the oxidation of cyanide to cyanate and carbonate, and the precipitation of metal. Changes in the platinum cyanide bath are relatively slow. The protection against oxidation afforded by the platinum-group metal coatings is evaluated by testing encapsulated specimens in a thermogravimetric balance. Surface pretreatment and the use of undercoats are discussed.

Jan 1, 1977

By D. O. Kennedy

"INTRODUCTION During the recent war attention was directed to prevent the destruction of American industries by sabotage. By Executive order of Lay 19, 1942, the Bureau of Mines was required to conduct investigations and make recommendations that would prevent loss of production of essential war minerals. The Health and Safety Branch of the Bureau of Lines was able to extend its activities with minimum loss of time to include security surveys of the important mineral facilities in the United States.A Mineral Production Security Division was established in the Health and Safety Branch with funds appropriated for that purpose by Congress in April 1942. From July 1942 to July 1945 engineers of this division, under the direction of D. Harrington, Chief, Health and Safety Branch, and J. J. Forbes, Chief, Mineral Production and Security Division, conducted investigations of 1,560 metallic and nonmetallic mines and associated facilities in accordance with the requirements of the Executive order.PURPOSEAn analysis of losses in the production of minerals shows that failure or destruction of equipment either from deliberate or accidental causes produces essentially the same result. Maximum production is insured by the prevention of subversive activities, fires, and industrial accidents."

Sep 1, 1946

By Oliver Bowles

Accidental explosions in coal mines are due to various causes, but many of them can be directly attributed to coal dust; others that probably in no way depend on dust as a primary cause are propagated, greatly intensified, and made more disastrous by the presence of coal dust. The fact that coal dust in a bituminous mine will explode as a result of a fire-damp explosion has been generally accepted for many years, but the belief has also been held by many that coal dust is not in itself dangerous when unmixed with an explosive gas. Therefore, in past years little attention was given to dust in mines free from fire damp, and many disastrous explosions have resulted from lack of knowledge of the danger from coal dust. In the explosives gallery and experimental mine of the Bureau of Mines experiment station, Pittsburgh, Pa., it has been proved repeatedly and conclusively that coal dust will explode violently when no inflammable gas is present. PROPAGATION OF DUST EXPLOSIONS A coal-dust explosion is an extremely rapid burning or combustion of the coal particles. Their burning consists essentially of the combination of the hydrocarbons in the coal with the oxygen of the air, a process that generates heat and flame and produces hot gases and water vapor. These gases and vapors have a volume many times that of the original coal particles; thus they exert an outward motion and pressure which constitute the explosive wave. When fine particles of coal are suspended in the air, each particle is surrounded by the oxygen of the air, and thus is well placed to oxidize or burn rapidly whenever the temperature is high enough. If some particles are ignited from any cause they will fire others, and the combustion will extend from particle to particle with extreme rapidity wherever enough coal dust of sufficient purity is present.

Jan 1, 1925

By R. L. Kidd, T. H. Miller

"INTRODUCTION This paper is the seventh of a series of yearly reviews started in 1921 and pre¬sents information gathered in a cooperative investigation undertaken by the United States Bureau of Mines and the University of Utah. It is the purpose of this report to make available flotation—reagent consumption data and other milling information in such a manner as to be of value to the milling industry and to the manufacturer of flotation reagents.These data have been compiled from a survey of about 300 concentration plants in the United States. Much additional information has been obtained from the various offices of the United States Bureau of Mines. Many of the plants covered in the survey made complete reports of their operations, but others were apparently unable to supply this information in sufficient detail to meet the requirements of this report. As a result, some sections of the report are more complete than others. In general, however, the mill reports were much more complete than in previous years, and for the first time it has been possible to calculate average mill recoveries in the treatment of certain classes of ores. As in the past, every effort has been made to conceal individual plant operations.ACKNOWLEDGMENTSIt is realized that the publication of this information is possible only through the assistance of the mill operators, and the authors wish to express their appreciation of this cooperation. Thanks are also due the various field offices of the United States Bureau of Mines, division of mineral statistics, for assistance in collecting this information."

Aug 1, 1931

By J. R. Thoenen

[For several years the Bureau of Mines conducted tests on ground vibration t emanating from quarry blasting in an effort to determine an index of destruction for different types of structures. Results of these studies have been published in four Bureau of Mines Reports of Invitations as well as in several articles in the trade and technical press.5/ The first paper (3)6/ discussed the subject in general and gave results s of a few blasting records. Some tentative theories also were advanced. The second paper (4) discussed results s of records made from blasting in a number of quarries.]

Jan 1, 1940

By J. R. Thoenen

[For several years the Bureau of Mines has conducted tests on ground vibration emanating from quarry blasting in an effort to determine Fin index of destruction for different types of structures. Results of these studies have been published in four Bureau of Mines Reports of Investigations as well as in several articles in the trade and technical press.5/ The first paper (3)6/ discussed the subject in general and gave results s of a few blasting records. Some tentative theories also were advanced. The second paper (4) discussed results s of records made from blasting in a number of quarries.]

Jan 1, 1940

By N. R. Dixon

This report summarizes all work performed under U.S. Bureau of Mines Contract No. J0395028, "Noise Control of Rubber-Tired Front-End Loaders Used in Surface Mining. " Two loaders, a Caterpillar 988 and an International H-400B, were chosen for this program, and the noise sources and acoustic paths that contribute to the operator's noise exposure were identified. Retrofit noise control treatments were designed and installed on these loaders, and noise reductions of more than 10 dBA at the operator position were achieved on both machines. The retrofit packages are low cost and have been field tested in two mines for more than two years. The results of the program were communicated to the mining industry through a series of noise control workshops and a field manual. The workshops were given in nine states across the U.S. and more than 440 manuals were distributed An audio/visual slide presentation was also developed which the program.

Jan 1, 1983

From the time of its establishment in 1910, the Federal Bureau of Nines has studied the carbonization of coal, and a considerable part of this effort has been devoted to investigations in the so-called low-temperature carbonization range, 450° to 700° C., in which there is minimum decomposition of primary products and maximum yield of Liquids - a yield two to threefold the amount produced in high-temperature carbonization at 900° to 1,200° C, The solid residue, char, or coke, produced in low-temperature carbonization is 70 to 80 percent of the coal charged and may be used directly as a smokeless fuel or for blending with coals to produce metallurgical coke, Although some thought was given to the use of tar and to the illuminating value of gas derived from lm-temperature carbonization, the main emphasis in early work of the Bureau of Mines was on the preparation of smokeless fuel, especially for home use, For example, a carbonizer was designed and operated for making char and briquets from North Dakota lignite without recovery of by- products; however, the shortage of high-temperature coal-tar products in the United States during World War I had already indicated the potential usefulness of low-temperature tar.

Jan 1, 1959

By P. S. Haury, Thomas C. Denton

"INTRODUCTION AND RESUMEThe Reward zinc property was one of the first selected for exploration by the Bureau of Mines at time when zinc supplies for war production were very short. Preliminary examination indicated that an appreciable tonnage of zinc that could be developed for early production might be found by diamond drilling. The geology was mapped by the Federal Geological Survey, and 14 holes were diamond drilled by the Bureau of Mines. This work was started in September 1942 and completed in September 1943.The Reward is an old property in southwestern Pinal County, 26 miles from Casa Grande on the Southern Pacific Railroad. Mining was begun in the early 1880's and was continued intermittently by several operators to about 1917. About 400,0oo pounds of copper was produced from the north¬eastern part of the property, mainly from a 600-foot incline in oxidized copper ore that replaced a bed of limestone. This ore was mined out. A 400-foot vertical shaft in the copper area was inaccessible. A 325-foot vertical shaft had been sunk near the southwest end of the zinc-bearing area, and a 600-foot crosscut tunnel had been driven near the northeast end of the zinc area, but little zinc ore was produced. There were several shallow inclines and numerous surface pits between the main workings.The ores were deposited in Paleozaic limestones that strike northeast and dip about 40 degrees northwest. These are capped by Cretaceous clastic and volcanic rocks in the zinc area. The outcrops show mineralization in a segment of the limestone 4,500 feet long, which is limited by large cross faults at each end. Another large fault, which strikes north, separates the northeast third of the mineralized belt from the remainder. Copper predominates northeast of this fault and zinc southwest of it. The ore beds are cut by numerous small cross faults. Ore was deposited for short distances along some of these, but more of it made out from the fissures along certain replaceable limestone beds."

Nov 1, 1946

By N. M. Safaya

Moderate to acute deficiency of plant available phosphorus is very common in western coal mine spoils and topsoils. Although some of the spoils are known to contain seemingly adequate amounts of total phosphorus, the plant available phosphorus is so low that it constitutes a serious plant growth limiting factor in the mined lands. For the revegetation of these spoils, the use of species, varieties and ecotypes exhibiting greater efficiency for P uptake and utilization, or conversely, lesser susceptibility to P deficiency would be highly desirable. To identify such plants, quick and adequate methods of screening germplasm should he available. In the present growth chamber study several plant species were screened using continuous flow culture and spoil culture systems to provide information on their relative susceptibility. In flow cultures, P was maintained at 0.25, 2.5, and 25 moles; while in spoil cultures it was applied at 0, 25, and 75µg/g to a P-deficient spoil. Phosphorus deficiency symptoms appeared in alfalfa cultivars, birdsfoot trefoil, emerald crownvetch and yellow sweetclover within 7-10 days upon transfer of their seedlings to U.25 or 2.5 µM P solutions. Burning bush and Russian thistle, found abundantly as pioneering species on mine spoils, showed no deficiency symptoms; their shoot dry matter yield in the 0.25µM P treatment was 24% and 36%, respectively of their maximum yield obtained with 25 µM P. However, the percent increase in the dry matter yield of legumes with 0.25 µM P ranged from 7-13% over their maximum yield. With the increase in solution P concentration, the root dry weight ratio in the legumes increased from an average of 0.22 to 0.43, while in the weeds from 0.14 to 0.30. The low susceptibility of Russian thistle to P deficiency was also demonstrated in the spoil culture experiment. Legumes showed greater response to P-fertilization on the spoil than did the two weeds. With increasing concentrations of P in the solution, the root weight ratio of all the species decreased. At 25 µM P, weeds invested only 14% of their total dry matter yield in the root fraction, where as legumes and grasses invested as much as 24% and 33% respectively. Weedy species averaged higher P concentrations than the legumes and grasses. The mean P concentrations of alfalfa cultivars were the lowest among legumes. In general, P concentrations increased with the increase in P supply. In the flow culture system, P supply increased the Ca levels of legumes. The mean Mn concentrations were highest in the weedy species. The increases in P supply decreased Zn levels in all of the species. File effects of P fertilization on the tissue concentrations of Mn and Zn in spoil culture were similar to that of flow culture system. From this preliminary study, it may be concluded that the continuous flow culture system is efficient in rapid screening of a large number of species under controlled conditions for their efficiency in adapting to mineral stresses.

Jan 1, 1982

On April 1, 1982, the Bureau of Mines and the Department of Energy entered into an Interagency Agreement to develop an enhanced computer cost model for uranium in situ leach mining. The original computer cost model contained data base information related to two regions; the Wyoming basin region and the South Texas trend area. The enhanced cost model contains additional information on San Juan Basin type deposits. This addition is significant because it expands the model's capabilites to include one of the largest uranium producing areas in the United States and developes costs related to uranium production from in situ leach mining. The data base was expanded and modified to include changes necessary for San Juan basin type deposits. These changes included, but were not limited to, state and local taxes, royalty payments, depth of deposits, drilling costs, and electrical costs. Also site visits were taken to verify many of the base case parameters. Consequently, the data base has been incorporated into the computer program and existing software was modified to provide for the additional data. Information was obtained on drilling coats and therefore the current program more accurately reflects these costs to depths of 2500 feet. This depth parameter has been expanded to include Wyoming Basin and South Texas scenarios also. Verbal communications were held with one operator in the Crownpoint, New Mexico area as well as the state regulatory agencies to help validate the expanded model. As a result of these changes, several tables have been included, summarizing changes in the new default parameters and the overall range of input parameters.

Jan 1, 1982

By Donald P. Tuchman, Robert P. Vinson, Steven J. Page, Linda J. McWilliams, Gerald J. Joy, Steven E. Mischler, Jon C. Volkwein

The National Institute for Occupational Safety and Health (NIOSH), through an informal partnership with industry, labor, and the Mine Safety and Health Administration, has developed and tested a new type of instrument known as the personal dust monitor (PDM). The dust monitor is an integral part of the cap lamp that a miner normally carries to work and provides continuous information about the amount of respirable coal mine dust in the breathing zone of that individual. Testing was conducted on 25 prototype instruments in the laboratory to verify the instruments’ accuracy as received from the manufacturer and after a period of underground use. The laboratory testing verified previous work; there is a 95% confidence that the individual PDM measurements were within ±25% of reference measurements. In-mine testing determined the precision, durability, and miner acceptance. Data from the mines showed a field precision of 0.078% relative standard deviation for the PDM and 0.052% for the recognized standard—the coal mine dust personal sampler unit. The PDM had about 90% availability for collecting valid information in over 8,000 hr of underground use. Anecdotal comments by miners indicated that they found the PDM more convenient to wear for sampling than currently used instruments because of the integration of the sampler into the normally worn cap lamp. The means of the instruments’ pre- and postmine accuracy verification test values were statistically equivalent. Additional data were collected to measure the equivalency of the PDM to the U.K. Mining Research Establishment sampler, as required by U.S. law. However, analysis of the data was more complex than originally anticipated because the variance with increasing concentration required use of a more sophisticated statistical model. Explanation of and results from this work will be the subject of a second publication. Under the broad range of test conditions covered in this work, the PDM functioned as well as the current sampler in terms of availability for use, accuracy, precision, and miner acceptance.

Jan 1, 2006

By J. W. Thompson

RIGHT OF LIFE TENAN1' TO OPEN MINES. The common-law rule that a life tenant was not permitted to open or share in mines does not prevail in Michigan; but a life tenant by dower right is permitted to share in the royalties, as the strict common- law rule is not in harmony with the spirit of our institutions and the policy of our law and would often result in defeating the purposes of dower statutes. Poole v. Union Trust Co. (Michigan), 157 Northwestern 430, p. 432, March, 1916. SALE AND CONVEYANCE. PURCHASE OF ENTIRE ESTATE--FRAUD. A purchase of land where no exceptions or reservations of minerals were made and the land was bought as property, when nothing is excepted and no qualifications or reservations are embodied in the agreement, was presumptively and by common understanding a purchase of the property in its entirety; and the insertion in the deed of a reservation of mineral rights in violation of the contract of purchase and without the grantee's knowledge or consent was fraudulent. Mtynarczyk v Zyskowski (Michigan), 157 Northwestern 566, p. 569, March, 1916. RESERVATION OF MINERALS--EXTENT AND EFFECL A reservation in a conveyance of land excepting and reserving to the grantor all coals and mines beneath the surface with the sole right and privilege to remove the same, is not as broad as the grant itself. A contract for the purchase of a mine recited that a deed had been executed by the owner and placed in escrow to so remain until the sum of $30,000 should be paid. The contract provided that $1,200 of the purchase price was to be paid in cash, $800 in 60 days, and the remainder out of 20 per cent of the gross output of the mine, such per cent to be paid in five years unless the vein and value of ore should not continue in depth, in which event the purchaser was to have two years longer to complete the payment of the purchase price. The contract contained other covenants to the effect that the purchasing corporation would fit up a certain specified mill and would continue development work at such rate as to keep the mill in operation if ores sufficiently valuable should be found and in the absence of unavoidable accident. The contract also provided 1/ that abandonment of work for a period of six months at anyone time, except as above, on said property," should operate as a forfeiture of the purchaser's right. In an action by the vendor to quiet the title to the land and to have the contract declared void, the court found that the purchaser failed to perform the work on the property and failed to place thereon the improvements as required by the contract and permitted debts to accumulate against the property, taxes to be levied thereon, and that for more than a year the purchaser had not done any work or labor of any sort upon the mine or premises, and that the contract contemplated development work from the time the purchaser took possession of the property, or at least promptly thereafter, and the fact that no machinery was in place for a year or more after the execution of the contract was a breach of the covenant of continued development, and that the clause in the contract" except as above" does not contemplate a delay in the development resulting from a failure to install machinery, but it means that unless prevented by unavoidable accidents the purchaser shouLdhave no valid excuses for neglecting the work for a period of six months or more.

Jan 1, 1917

By Rose L. Ballard

This chapter summarizes data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rico. Included also are the tables that show the principal nonfuel mineral commodities exported from and imported into the United States and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of volume I and in the State chapters of volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at any of several stages of extraction and processing, the stage bf measurement used in this chapter is what is normally termed "mine output." It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines.

Jan 1, 1983

By James R. Kerr

This study reviews the sulfur and suliuric acid industries in Eastern United States with emphasis on patterns of consumption and marketing. Output of sulfur in the East is relatively small, and most of the area's sulfur requirements are met by gulf coast Frasch sulfur. Over the long ten recovered elemental sulfur from sour natural gas and petroleum may become the East's major source of sulfur. In 1958 sulfuric acid manufacture consumed over 80 percent of the area's sulfur requirements. The leading uses for sulfuric acid were the manufacture of superphosphates and chemicals. Over the years, unit requirements for sulfur and acid in many major markets have been reduced through improved technology, but new markets always have been developed to keep the industry vital and growing.

Jan 1, 1965

By Robert Torbin

The objectives of the Continuous Shaft Lining (CSL) System are to reduce the costs, safety hazards, and time currently required in lining mine shafts with concrete. The CSL will line machine bored shafts downward from the shaft collar on a continuous basis using an inverted, pressurized slipforming technique. The technique for slip-forming downwards has been demonstrated and refined under this program. The approach taken involved laboratory scale testing of key features of the CSL concept. These feature tests included concrete distribution, concrete sealing, concrete slipforming and development of a reliable concrete mix. Based on these results, a full scale above-ground test facility and CSL were designed and fabricated. The objectives of these tests were to demonstrate the viability of the basic concept; to establish operating limits; and to provide input data and information for the design of a second generation shaft lining system. The results of the program have led to a CSL design and operational philosophy which will need to be tested in an underground environment before industry will accept the technology. However, the next generation CSL promises to meet all the original program technical objectives.

Jan 1, 1983

By James R. Kerr

This study reviews the sulfur and suliuric acid industries in Eastern United States with emphasis on patterns of consumption and marketing. Output of sulfur in the East is relatively small, and most of the area's sulfur requirements are met by gulf coast Frasch sulfur. Over the long ten recovered elemental sulfur from sour natural gas and petroleum may become the East's major source of sulfur. In 1958 sulfuric acid manufacture consumed over 80 percent of the area's sulfur requirements. The leading uses for sulfuric acid were the manufacture of superphosphates and chemicals. Over the years, unit requirements for sulfur and acid in many major markets have been reduced through improved technology, but new markets always have been developed to keep the industry vital and growing.

Jan 1, 1965

Three complete connector assemblies and six separate contacts were submitted to a series of tests to establish the connectors permissibility and compliance with U. S. Bureau of Mines research Contract #H 0110423 D.C. portion. Test Procedure TPC-0118 was coordinated, and the test plan approved by the Bureau as fully complying with the intent of the contract for the direct current connectors. The components and connector assemblies have been demonstrated in testing that they meet or exceed all the requirements of the test procedure.

Jan 1, 1974