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By D. Harrington

The placing of much, sometimes practically all, of the burden of the expense of mine accidents on the shoulders of the mine operator by compensation laws, and the fact that the problem of protecting the life end limb of workers is now by public opinion largely if not wholly passed to each industry to solve (and present-day thought strongly supports the justice of both of these propositions), are forcing industrial organizations into accident-prevention. Work. This policy is being adopted not alone to protect the companies; in addition, executives alert to their opportunities and obligations are taking part in this work personally to protect themselves. The functions of industrial executives in accident-prevention work are becoming numerous and complex. Executives who are logical in their reasoning, quickly see that before a company can constantly ask or expect the workers to heed safety suggestions, the company and its officials must "put their house in order" by laying down a concrete, definite safety program. For mines this includes primarily adoption of a to a logical mining method, the installation of safe miming equipment and practice the netting forth in definite form (preferably do a printed pamphlet) of the company's minimum safety requirements, and the organization of its operating officials into an accident-prevention body. After the company has its own affairs so arranged that it can go to its workers with "clear, hands" in promoting a safety program, the real work begins; and this is especially applicable in mining.

Jan 1, 1939

In 2006, 14,885 mining operations reported employment data to the Mine Safety and Health Administration (MSHA).1 Almost half (48.2%) were sand and gravel mines, followed by stone mines (30.7%), coal mines (14.2%), nonmetal mines (5.0%), and metal mines (1.9%).

Jan 1, 2008

By William F. Jahn

Because of the' situation in Europe during the summer of 1939, with the possibility of war and consequent curtailment or loss of supplies of tin to the United States, the Bureau of Mines undertook an investigation of domestic tin resources. This was permitted by the Strategic Minerals Act of 1939, which authorized investigation of possible domestic resources of strategic minerals necessary in a national emergency. The minerals selected were in short supply, and the United States depended almost entirely on imports to meet normal requirements. The Black Hills of South Dakota were selected for investigation as one possible source of tin because of the occurrence of the mineral there has been known since 1876, although production had never been important. The Tinton area, in the northern part of the Hills, had received the most attention and contained some minor indicated and inferred tin deposits.

Jan 1, 1949

By R. C. Corey

Anticipating the need for convenient, economical, and safe means for disposing of combustible wastes contaminated with low-level activity, in connection with private and institutional uses of radioisotopes, the Atomic Energy Commission (AEC) has provided the Bureau of Mines with funds to develop an incinerator for this purpose. A prototype incinerator, designated hereafter as BOMAEC-30, was designed, constructed, and tested, based on fundamental and applied research investigations of the combustion characteristics of rubbish and sawdust, which will comprise the bulk of contaminated wastes. No radioisotopes were used in the tests; the objective was to remove as much particulate matter from the products of combustion as possible. The prototype unit was designed to burn 30 pounds per hour, using 100 percent over fire air admitted tangentially in an all-metal, cylindrical combustion chamber. The gas-cleaning system consisted of special fabric bags and absolute filters.

Jan 1, 1962

By Carroll W. DeKock

Thermodynamic data for selected metal sulfates were critically evaluated and compiled as part of the Bureau of Mines program to provide a scientific base for use in developing new technology and predicting the feasibility of new processes. Values for Cp°, S°, H° - H°298, - (G° - H°298)/T, ?RC, ?Gf°, and log Kf as functions of temperature are given in tabular form. Thermodynamic data were compiled for Ag2SO4, A12(504)3, A12(S04)3?6H20, BaSO4, BeSO4, BeSO4?2H2O, BeSO4?4H20, CaSO4, CaSO4?1/2H20, CaSO4?2H2O, CdSO4, CdSO4?H20, CdS04?8/3H20, 2CdO?CdSO4, Cs2SO4, In2(S04)3, K2504, KA1(S04)2, KA1(S04)2?12H20, Li2SO4, L12SO4?H20, MgSO4, MgSO4?H2O, MgSO4?2H20, MgS04?4H20, MgS04?6H2O, MgS04?7H2O, Na2SO4, Na2S04?7H20, Na2SO4?10H20, (NH4)2SO4, NH4A1(S04)2, NH4A1(S04)2?12H20, PbSO4, Rb2SO4, T12SO4, and Zr(S04)2.

Jan 1, 1986

By J. J. Forbes

The Act of Congress authorizing the establishment of the United States Bureau of Mines became effective July 1, 1910. One of the most important duties Congress delegated to the Bureau in this Act was the study of health and safety conditions in the mineral industries. Early investigations of these conditions revealed the need of prompt Care of injured employees, as, under the difficulties inherent in their occupation, seemingly unimportant wounds if not treated promptly might become infected and cause permanent disability or even death. Many seriously injured persons brought out of mines and plants by fellow workers ignorant of approved methods of giving first aid or of safe means of transportation have been caused suffering and have had injuries accentuated to such a degree as to bring about permanent disability or death. The need of general instruction in first aid thus became apparent. BRIEF HISTORY OF FIRST-AID WORK The education of miners in the United States in first aid probably was conducted systematically first by the anthracite industry in Pennsylvania. Subsequently, first-aid training was carried on actively in Alabama and Indiana. Meanwhile, a general training campaign was carried on among industrial workers by the American Red Cross Society; when the Bureau of Mines began its nation-wide campaign of instructing employees of the mineral industries, the Red Cross turned over that part of its industrial training work to the Bureau but continued to cooperate by furnishing surgeons as judges in important first-aid contests and demonstr tions and assisted for a number of years in determining training methods.

Jan 1, 1937

By Stephen D. Hill

The Bureau of Mines devised and constructed a modified Knudsen effusion apparatus, permitting a constant measure of the weight of effusing vapor, to determine the equilibrium vapor pressure of metal halides at temperatures up to 1,200° K and over the pressure range 10-5 to 10-2 torr. The reliability of the apparatus was established by determining the vapor pressure of potassium chloride. After correcting for partial dimerization of the vapor, data obtained on solid KCl between 750° and 950° K can be expressed by the following equation:

Jan 1, 1966

By J. Douglas Causey

The Bureau of Mines conducted mineral investigations of the Peace Rock and Deadwood River roadless areas in Idaho, in 1992. Literature research was done by the Idaho Geological Survey. The study areas contain black sand placers (thorium, columbium, tantalum, titanium, uranium, and rare earth elements), gold, and molybdenum prospects. Except for unrecorded placer gold, there has been no mineral production from the areas. No mineral resources were delineated, but a multi-million tonne molybdenum resource is in the Big Pine Creek area and a 142 million m' black sand deposit is in the Stolle Meadows, Peace Valley, and Deadwood River areas. The Deadwood mine produced zinc, lead, and silver. There are six mining districts in and adjoining the areas; Warm Lake, Deadwood, Garden Valley/Lowman, Banner, Summit Flat, and Grimes Pass. Few claims, mostly placer, were active in the study area in 1992. The study areas are underlain by granitic rocks of the Idaho batholith. Most of the deposits are alluvial accumulations of heavy minerals weathered out of the Idaho batholith. Stockwork and narrow veins along shears account for the base and precious metal concentrations. Eleven prospects were examined. Workings consist of drill holes, pits and adits. Geothermal resources (hot springs) occur mainly along the Middle Fork Payette River; Vulcan Hot Springs is a designated Known Geothermal Resource Area. Sand and gravel resources are of local interest.

Jan 1, 1993

By E. E. Maillot

In 1943, diamond drilling by the Bureau of Mines, comprising 11 holes which totaled 1,295.6 feet, showed that the pegmatite at Black Mountain consisted of shallow lenses in interbedded biotite-quartz-schist and impure quartzite. The average thickness of the pegmatite was 9.7 feet. Mineralization had a zonal arrangement. Beryl was most abundant near the footwall contact of the pegmatite. The average estimated beryl content of the pegmatite exposed at the surface was 0.81 percent, and the highest content of any pegmatite area was 1.75 percent. Other economic minerals were scrap mica, feldspar, spodumene, and lepidolite. Representative samples of the Black Mountain deposit failed to yield high-grade boryl concentrates by straight flotation owing to the presence of considerable spodumene. By employing heavy medium separation to remove the spodumene, 75.4 percent of the. BeO wan recovered in a flotation concentrate assaying 10.4 percent BeO.

Jan 1, 1949

By H. S. Auvil, J. T. McCartney, J. D. Davis

"INTRODUCTION It is now generally recognized that the small-scale laboratory dilatometer method of test does not give results of much utility in predicting the expansion (or contraction) of a coal in a coke oven. The carbonizing conditions in the laboratory test differ radically from those in the oven; in this test, the charge is heated through the coking range of temperature as a whole, whereas in the oven, coking proceeds by layers parallel to the oven walls as each succeeding portion of the charge goes through the plastic range of temperature and coke formation sets in. The paths of the gases and vapors and the pressures set up are different in the two methods. Furthermore, the rate of heating in the test usually is much more rapid than in the oven. H. Koppers 5/ was perhaps the first to adopt apparatus and procedure whereby the layer coking of the coke oven could be simulated closely however, the heating progressed from one side of the charge only; later he experimented with a small coke oven with a movable wall heated from both sides. It is not clear how well the results in the later oven correlated with those of the earlier small test oven, but in a comparatively recent Koppers publication a modification of the original small test oven heated from one side is recommended 6/ Altieri 7/ was perhaps the first to experiment with the Koppers type small test oven in the United States and Brown- has tested a large variety of coals in a rectangular test oven of his own design heated from the sole or floor. Subcommittee XV of American Society for Testing Materials Committee D-5 is now making a study of the various methods proposed for determination of expanding and plastic properties of coal with a view to standardization. 9/"

May 1, 1939

By R. Karl Zipf, Z. T. Bieniawski

"Fracture mechanics plays an important role in studies of geologic materials such as rock and coal. Yet fracture data are scarce for rock and most limited or unreliable for coal. A testing system was developed which can apply mixed mode loads to a crack tip in many rocks and geologic materials. It is possible to subject the test specimen to pure mode I, various mixed modes and a nearly pure mode II fracture load. The system is currently used to study the mechanics of fine fragment formation in various coals. Experimental measurements include KI and KII' fracture velocity and acoustic emission.INTRODUCTIONA major research program at The Pennsylvania State University is directed to understanding the fundamental mechanics of fine fragment formation in various coals. The program represents an effort to reduce the incidence of coal workers pneumoconiosis (black lung) in coal miners. The principal source of the respirable coal fragments is the cutting operation which forms and liberates the particles by a fracture process. Present understanding of the mechanics of the events which form and liberate these particles is meager (Cook, 1982).Current knowledge of the fundamental mechanisms of coal dust generation and entrainment in terms of the underlying fracture mechanics is critically needed to improve and possibly control the processes involved. Whether the cutting operation is done with a 'continuous miner' cutting machine, a plow or a longwall shearer, it is fundamentally a problem of mixed-mode crack propagation. When a cutting tool interacts with coal, it causes numerous cracks to propagate through the intact material. Numerous larger fragments are broken free, but another quantity of undesirable fine fragments is also created. The formation of these respirable fragments may be a direct result of the crack propagation process; hence, a thorough understanding of the fracture mechanics of coal is required to minimize production of the unwanted fine fragments.In most rock engineering applications, the rock material properties are of secondary importance to the rock mass properties; however, for rock fragmentation and rock cutting problems, it is rock material properties such as fracture toughness which are of prime interest (Bieniawski, 1980). Several rock cutting and rock failure theories have been proposed, but it is only very recently that fracture mechanics concepts have been successfully applied to the study of rock cutting mechanics. All cutting models seek to predict the cutting forces and the cutter geometry necessary to cause rock breakage and chip formation given some fundamental mechanical properties ~f the rock. Such models have wide applications in drilling, tunnel boring and mining problems. Nelson et al., (1985, 1986) has provided a very useful correlation between the laboratory measured fracture mechanics properties of rock and the performance of the disk cutters on tunnel boring machines."

Jan 1, 1989

By S. J. Aresco

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analyses. To these, when required, are added the ash-softening temperature, the free-swelling index, and the Hardgrove grindability index. Under most of these specification contracts the bidders guarantee the quality of the coal, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled in accordance with instructions4 issued by the Bureau of Mines; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor; if it is not, a price adjustment is made. Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous sampling of coal as delivered is a check on the practical results obtained in burning the coal.

Jan 1, 1966

By Ernest V. Deshayes

The Colorado Minerals Co. calcite properties in Archuleta and Hinsdale Counties, Colo., (fig. 1) were examined by Bureau of Mines engineers in 1943. The demand for optical calcite during the war prompted the examinations and resulting development programs on the Meadows and Seavy ranch properties near Pagosa Springs, Archuleta County. Development was begun on the Meadows property in November 1943 and continued to the Seavy ranch property. The work consisted of stripping the overburden from the calcite areas and excavating pits and trenches with a bulldozer. The pits and trenches exposing the most promising calcite veins were then deepened by hand, and one shaft was sunk to a depth of 30 feet. A total of 36 trenches and 9 pits were excavated by bulldozer and. hand methods (figs. 2, 3, and 4). The calcite deposits occur as veins and irregular bodies filling fractures in the Mancos shale of Cretaceous age. The fractures persist for considerable distances along the strike, although the calcite filling may not be continuous for more than a few feet. The widths of individual veins range from a few inches to several feet. The calcite crystals uncovered at the surface and in pits, trenches, and shafts were found to be unsuitable for optical purposes because of fracturing and color in the crystals.

Jan 1, 1949

By C. L. Karr

U.S. Bureau of Mines (USBM) research has shown that fuzzy logic and genetic algorithms (GA's) have great potential for industrial process control. A technique has been developed by the USBM in which GA's are used to substantially reduce the time needed to design fuzzy logic controllers (FLC's).This technique shows promise as an efficient, robust approach to developing control systems. The research described in this report is twofold. First, the basic approach to developing an FLC using GA's is presented. The GA-designed FLC is developed for a specific physical system, a pH titration system. Second, empirical results are presented in which variations in the FLC implementation are compared. Specifically, the effects of altering five aspects of the pH FLC are considered: (1) membership function form, (2) number of fuzzy classes, (3) the center-of-area method, (4) implication operator, and (5) fuzzy rule form. Results indicate that (1) the technique in which GA's are used to design FLC's is effective, and (2) when this technique is used, variations in FLC implementation have little effect on FLC performance in a chosen control problem.

Jan 1, 2010

By J. Vance Batty

Two methods were devised and evaluated for quantitatively measuring the amount of oleic acid on flotation products and in flotation waters. One method involved use of an organic solvent to remove carbon-l4-tagged oleic acid from mineral surfaces and flotation water phases with subsequent radio-metric analysis of the extracts. Studies showed this method to be slow and subject to large variations in accuracy and reproducibility. In the second procedure, tagged oleic acid was measured directly on the surfaces of dried mineral products. Oleic acid in the water phase was determined by adsorbing it on fine mineral, drying, and radiometric counting. Quantitative analysis of oleic acid on flotation products from bench-scale flotation tests with synthetic mixtures of ore minerals and quartz and with natural ores showed this method to be fast, accurate, and reproducible.

Jan 1, 1968

By Edward E. Johnson

The U.S. economy boomed in 1965, completing its fifth consecutive year of expansion. Although the advance was somewhat irregular, previous records for production, sales, employment, and income were topped. During the first few months of 1965, as the economy recovered from the depressing effects of the automobile strikes of late 1964, increases were unusually large. The gains moderated in early spring, but were stimulated at midyear by sharply rising capital outlays, excise tax cuts, in? creased Social Security payments, and accelerated Viet-Nam defense expenditures. Gross national product (GNP) in cur-rent dollars rose $49.5 billion or 7.8 percent, to a total of S681.2 billion. In constant dollars (effects of price changes eliminated), GNP increased 5.9 percent, a rate considerably higher than the historical postwar annual average growth of 3.5 per-cent. Demand increased in most final markets and was especially strong for business fixed investment and consumption expenditures. With the exception of construction, most of the increases in GNP were real, since prices increased less than 2 percent.

Jan 1, 1966

By R. V. Holmes

The properties of the Colorado Copper Co. in Sinbad Valley, Mesa and Montrose Counties, Colo., were rehabilitated and sampled by the Bureau of Mines in October, November, and December 1942. The several deposits were reexamined in March and April 1945 to obtain information disclosed by company work after December 1942. The development program included surface trenching, rehabilitation of several edits, and channel sampling of the exposures. Assay determinations wore made on 204 samples from the surface and underground workings. The results are given in the appendix. Several copper deposits in the Sinbad Valley area are similar in origin. The host rocks are sedimentary and mice in age from Pennsylvanian to Cretaceous. The Colorado No. 3 deposit occurs in the Cutler formation, which consists of many small lenses of conglomerate, sandstone, and shale. Mineralization is closely associated with faulting. On the Pyramid group the enrichment occurs in a zone of fracturing and jointing end also spreads into the adjoining sandstone. The ore deposition on the Copper Rivet claim is associated with a fault zone and is confined to en area above the contact of the Dolores-Wingate formations. Mineral deposits on the Sinbad claims occur at intersections of faults with blue-gray Pennsylvania limestone. Copper enrichment occurs along faults and as replacement of the surrounding limestone. Metallurgical tests indicate that ores from the Colorado No. 3 and Pyramid claims can be treated successfully by leaching with sulfuric acid. This method cannot be applied to ores from the Copper Rivet or Sinbad deposits because of high calcite content. Flotation tests at Boulder City, Nev., showed a recovery of less than 60 percent with a 14.24 percent copper concentrate.

Jan 1, 1952

By O. C. Blade

"INTRODUCTION This report on the properties of motor fuels sold through service stations in the United States is a continuation of a series of reports made in accordance with a cooperative agreement between the Coordinating Fuel Research (CFR) Committee of the Coordinating Research Council (CRC) 3/ and the Bureau of Mines of the United States Department of the Interior. The first of these reports presented data on motor gasolines sold during the winter of 1935-36.4/ Further reports were issued describing motor gasolines sold during the succeeding sum¬mers and winters to and including the summer of 1941.4/ No reports were made on motor gasolines sold during the winter of 1941-42 and during the summer of 1942. However, starting with the winter of 1942-43, the semiannual reports were resumed.!The present report presents analytical data for 4,544 samples, represent¬ing the products of 124 companies. The samples represented in this report were obtained during December 19146, January and February 19-(. As in previous surveys, the companies covered Ly the survey include both large and small suppliers. Conforming to former reports, the data cover three groups of samples - regular-price, premium-price, and third-grade gasolines.As the number of analyses submitted for samples of third-grade gasoline are not considered adequate to represent this type of motor fuel, data for the analyses have not been averaged, but the individual items are tabulated. The number of samples, items, and brands comprising each group is as follows: Regular-price, 2,368 samples, 319 items, and 113 brands; premium-price, 2,172 samples, 289 items, and 106 brands; third-grade, 4 samples, 4 items, and 4 brands. The meanings of these terms as used in the surveys are as follows:"

Aug 1, 1947

The original work statement of this contract was entitles: 'A Accident Analysis Model for Use in Underground Coal Mines.' The contract was scheduled for a duration of 26 months and was to be in three phases: Phase I - Model Development, Phase II - Application of the Model, and Phase III - Installation, Monitoring and Evaluation of the Model. Alter three months in Phase I, it became apparent that much of the needed data for the model was nut available and could not be made available within the original study schedule. Proceeding as plumed would have resulted in a model of limited utility. Personnel from Theodore Barry and Associates and the Bureau discussed the problem in detail and mutually decided to utilize the majority of remaining funds to assist the Bureau in solving these data problems and develop a stronger ongoing capability for safety analysis within the Bureau. Both tie contractor and the bureau officials involved believed that this decision greatly enhanced the Bureau's ability to develop future accident prediction models, whose rigor would greatly exceed what was currently possible.

Jan 1, 1972

By R. G. Sandberg

Many gold-bearing ores throughout the Western United States contain small quantities of mercury. The presence of mercury not only decreases the gold-loading capacity of the activated carbon, but complicates the fire refining of cathodes and creates a potential health hazard. The Bureau of Mines investigated methods to limit mercury extraction during gold ore leaching and to remove mercury from cyanide leach solu-tions. Mercury dissolution was reduced from 40 to 10 pct by decreasing NaCN concentration from 20 lb to 0.34 lb per ton of solution at a pH of <11. When 0.1 lb CaS per ton of ore was added to a leach slurry, mer-cury extraction was reduced from 27 to 0.4 pct. Less than 0.5 pct of the mercury was solubilized when <0.1 lb CaS per ton of are, along with lime and NaCN, was added to a simulated grinding circuit.

Jan 1, 1984