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By Ε. P. YoUNGMAN

This paper presents one of a series of digests of foreign mining legis- lation and court docisions that is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate mines in vericis foreign countries. This interpretation of the laws - of Italy has been prepared, in part, from an aclysis made by John W. Frey, for merly associate mineral economist, U. S. Bureau of Mines. It incorporates addi- tional data and comments offered by Enrico Giobbe Della Pitta, a well-known Italian lawyer, in response to a questionnaire. These comments were forwarded by Harold H. Tittmann, American chargé d'affaires ad interim, at Rome, and trans- mitted to the Bureau of Mines through the courtesy of the Department of State.

Oct 1, 1930

By Wallace W. Roepke

The Bureau of Mines has a well-established health and safety research effort directed to fundamental studies of the mine cutting system. This report describes the ignition danger of using cutting bits with flat wear area on still-intact carbide inserts.

Jan 1, 1983

By John A. Davis, John Gross

Six tests were made by the Alaska Station of the Bureau of Mines on a sample of black sand delivered to the station by Messrs. James, Eagan & Griffen from Fairbanks Creek, Fairbanks mining district, Territory of Alaska, to devise a method of recovering the gold content. More than 90 per cent of this black sand consisted of magnetite and garnet which can be separated magnetically. The Station has no equipment for magnetic separation other than an electromagnet similar to the one used by Day and Richards, (Day, D.T., and Richards, R.H., Investigations of Black Sands from Placer Mines, U. S. Geol. Survey, Bull. 285, 1906, pp. 150-163), which can only be used satisfactorily on small samples. To treat the entire lot of black sand with this machine would have been impracticable. Therefore only a small part of the sand was so treated, the rest being divided into five lots in order to obtain comparative results from other methods of treatment.

Aug 1, 1920

By A. L. Murray, P. A. Surgeon

The Spring Canyon Mine Rescue Association is a cooperative association supported jointly by five coal-mining companies located in Spring Canyon, Utah. The properties of mining companies the Carbon Fuel Co, Rains , Utah, the Liberty Coal Co. , Latuda, Utah, the Standard Coal Co. , Standardville , Utan, the Spring Canyon Coal Co. , Storrs , Utah, and the Peerless Coal Co. , Peerless , Utah about a mile apart and normally employ a total of 915 men , 733 underground 182 on the surface . and The Association was organized on July 5, 1921 , and Rudolph Clark, fomerly first - aid miner on U. S. Bureau of Mines Rescue Car 11 , was placed in charge. as manager . A board of directors made up of a representative from each of the cooperating companies (usually the mine superintendent ) is the governing body of the Association and the expenses are prorated on a basis of the production of each of the five mines . The Association maintains eight sets of Gibbs rescue apparatus and a motor truck fitted up as a combined rescue truck and ambulance . Additional apparatus are to be purchased . Standardville is the central camp in the canyon and has been made the headquarters of the Association . The apparatus are now kept and the truck housed in a small station, but plans have been prepared for a large station which will be built this summer . This new station will have a large apparatus room , a test chamber, a suitable room. for training, and a garage on the first floor, while above will be the living quarters of the manager . There is a good road through the canyon and the other camps are all within two and one -half miles of Standardville .

May 1, 1922

By Bradley V. Johnson

The Bureau of Mines constructed a microminer--a scaled-down (5-by 5- by 11-foot) continuous-mining machine of the drum type with a unique triaxially controlled head--for use in a research program to study the effects of continuous-mining-machine parameters on the generation of respirable dust. This report describes field research with the microminer at the Bureau's Experimental Mine at Bruceton, Pa. Experiments were conducted to determine the effects of depth of cut, rotational speed, and sump and shear rates on the generation of respirable dust. The cutting forces were also monitored and compared with depth of cut. There appears to be a reduction in the amount of respirable dust generated when the depth of cut is increased or rotational is speed lowered, Variation of other machine parameters seems to have little effect on dust generation.

Jan 1, 1975

The Ringelmann Smoke Chart fulfills an important need in smoke abatement work and in certain problems in the combustion of fuels. A knowledge of its history and method of preparation is, therefore, of interest to many. Since instructions on its use are not shown on the recent edition of the chart, those included in this revision of the previous Bureau of Mines publication now are a necessary complement to the chart, More detail regarding the use of the chart is included than was given in the earlier version.

Jan 1, 1967

By Walter E. Lewis

Ventilation-air-heating plants are in use at several iron mines on the Menominee Iron Range, Iron River, Mich. Many of the mines are exceptionally wet; during winter months, when fresh air is forced down the wet air shafts into the mine, it is usually necessary to heat the fresh air to above freezing so that the openings will not be closed by ice. The problem of ice closing air shafts has been solved by the practice of reversing the air current before the openings have become completely closed. This procedure involves drawing warm air from the mine up the usual down-draft air shaft. The M. A. Hanna Co. has found, at some of their mines on the Menominee Range, that it is more convenient to heat the below-freezing air rather than reverse the air current. Intermittent freezing and thawing of ice that has formed in the air shaft tends to loosen the wall rock, requiring major shaft repairs. The openings are kept free of ice the year around by heating the fresh air during periods of below-freezing weather. Table 1 shows the monthly minimum moan, maximum mean, and mean temperatures for the Iron River area. Under normal conditions of temperature, the furnaces are fired in November and usually are not allowed to go out until April of the following year.

Jan 1, 1951

By A. D. Hahn

This report describes reconnaissance by the Bureau of Mines of titanium-bearing beach sands on Ship Island in the Gulf of Mexico off the south coast of Harrison County, Miss. The purpose was to determine the ilmenite, rutile, and associated heavy-mineral content of black-sand-bearing beach sands. The investigation was part of a survey of titanium resources of the United States. Ilmenite (FeTi03), an iron-titanium oxide, is the major titanium-bearing mineral consumed in the titanium pigment industry. Rutile (TiO2), titanium dioxide, is used mainly as a constituent in welding-rod coatings and in producing titanium metal. The major fieldwork was conducted during the first half of February 1961. Nine holes, totaling 220 feet of bore, from which 110 samples Her taken, were drilled at widely spaced intervals on the island.

Jan 1, 1962

By N. S. Dalal, X. Shi

"SUMMARYElectron spin resonance (ESR) measurements provide direct evidence for the involvement of the glutathionyl radical, as well as an isolable Cr(V)-glutathione intermediate in the Cr(VI) glutathione redox reactions. These results indicate a new mechanism for the reduction of Cr(VI) by glutathione in relationship to cellular environment and suggest that synergistic reactions of Cr(V) and GS· might be responsible for the (unexpected) increase in the Cr(VI)-induced DNA-strand breaks at high glutathione levels.INTRODUCTIONWhile the reduction of Cr(VI) by glutathione (GSH) is thought to be a critical' step in the pathogenesis of the Cr(VI)-exposure related carcinogenesis1- 4, the exact reduction mechanism is not yet understood. The following reaction steps have been suggested :(A) Initial step:Cr04 2- + GSH - GSCrOa - (1)(B) At high GSH levels:GSCroa- + GSH - Cr( IV) + GSSG (2)(C) At low GSH levels: GSC rO a - - Cr ( V ) + GS ·(3)Thus far, however, in these reactions, the GS· radical has eluded spectroscopic detection, while the evidence for the Cr(V) formation has been reported positives as well as negative2·. Her~ we present spin-trap ESR evidence for the formation of the GS· radical, and a definitive ESR detection of an isolable cr(V)-GSH intermediate in Cr(VI)-GSH reactions.MATERIALS. AND METHODSESR spectra were obtained at X-band (-9.7 GHz) using a Bruker ER200D ESR spectrometer. The magnetic field was calibrated with a self-tracking NMR Gaussmeter (Bruker, Model ER035M) and the microwave frequency was measured with a Hewlett-Packard (Model 5340A) frequency counter. The spin probes, a-(4-pyridyl-1-oxide) -N -tert-butylnitrone (4-POBN) and 5,5-dimethyl~1-pyrroline-1-ox1de (DMPO) were purchased from Aldrich, K2Cr201 from Fisher and used without further purification. All experiments were done at room temperature."

Jan 1, 1989

By F. H. Gibson

In recent years physico-chemical techniques have been applied for rapid analysis of coal and coke ash as replacements for classical wet-chemical methods. Although the classical methods are accurate, they are time consuming because many chemical separations are necessary to complete an analysis, and they require skilled analysts for accurate work (12).4 For the past several years the Bureau of Mines has applied some of the newer physico-chemical techniques in its continued search for new and improved methods at analysis. The methods of analyzing coal and coke ash evolved from this work include spectrophotometric methods far SiO2, A120, , Fe203 , TiO2, and P2O5; chelatometric titration for CaO and MgO; and flame photometry for Na20 and K2O. The methods are rapid and direct, are suitable for analyzing a group of samples at the same time in production work, and dire results with almost the same accuracy as classical procedures. With the new methods, complete analyses in duplicate can be obtained at a rate of 2 to 3 times that of conventional methods.

Jan 1, 1962

By R. R. Hornor

BIBLIOGRAPHY OF ARTICLES RELATING TO THE PRESERVATION

Apr 1, 1922

By Joseph Grumer

In addition to nine powder and gaseous extinguishants of propagating Pittsburgh seam coal dust-air explosions earlier evaluated,6 10 other powders have similarly been evaluated under like conditions such that wall quenching of the coal dust-air flames was virtually absent and the dust concentration was temporally and spatially uniform to within about ±5 percent. None of the newly examined extinguishants was better than Purple-K (potassium bicarbonate); the 10 of this report are anhydrite (calcium sulfate), monobasic (4 types) and dibasic ammonium phosphate, natural and synthetic cryolite (sodium fluoalumi-nate), sodium sulfate, and tricalcium phosphate. Except for anhydrite, sodium sulfate, tricalcium phosphate, and the cryolites, these materials were about equally effective, when present in relatively low concentrations (weight-percent of the coal dust-extinguishant mixture). The maximum oxygen concentration for the extinguishment of otherwise uninhibited coal dust explosions and the influence of coal dust particle size and the volatile content of the coal were also explored. For the present, the choice of the inhibitor among the good ones evaluated is not as critical as the system to be used to deploy the extinguishant against a coal dust explosion.

Jan 1, 1973

By Philip W. Holland

The U.S. Bureau of Mines has designed and built an inexpensive, weatherproof, temperature-controlled cabinet to provide temporary housing for analytical instrumentation. The cabinet consists of an inverted Styrofoam ice chest, an electric fan for air circulation, and a proportional temperature controller equipped with a thermistor sensor and a light bulb as the heater. The cabinet provides a constant-temperature environment for a moisture analyzer and a strip chart recorder when outside temperatures range from -SO to 21° c.

Jan 1, 1993

By Jeffrey B. Osmint

The Bureau of Mines Information and Analysis Directorate collects worldwide data on virtually every commercially important nonfuel mineral commodity. These data form the base for tracking and assessing the health of the minerals sector of the U.S. economy. The Bureau's data collection activity was instituted by the 47th Congress in an appropriations act of August 7, 1882 (22 Stat. 329), which placed the collection of mineral statistics on an annual basis. The most recent authority for the Bureau of Mines survey activity is the National Materials and Minerals Policy, Research and Development Act of 1980 (Public Law 96-479, 96th Congress), which strengthens protection for proprietary data provided to the U.S. Department of the Interior by persons or firms engaged in any phase of mineral or mineral-material production or consumption.

Jan 1, 1991

By H. H. Schrenk

One phase of the Bureau of Minest work in the field of health and safety is the promotion of safe, satisfactory, and reliable respir atory protective devices. To insure that such devices will be available, the Bureau has established schedules of what it considers the minimum re- quirements for oxygen breathing-apparatus,3 gas masks, hose masks,5/ and mechanical filter-respirators (a schedule of requirements for hose- type supplied-air respirators is being prepared). Approval of oxygen breathing-apparatus is given by the Safety Division; approval of other types of respiratory equipment is given by the Health Division, both divisions being in the Health and Safety Branch, Manufacturers of respiratory protective devices may submit their equipment to the Bureau for approval under the requirements of these schedules. As a prerequisite to submitting a device for approval, the Bureau requires a statement that the device is completely developed and of the design and material that the manufacturer believes suitable for a finished marketable device; that the device has been

Aug 1, 1937

By Lars Osen

The Bureau of Mines investigated (1) the effect of torsion on yield and ultimate strengths of bolts when the torsion is applied first and tensile load is applied independently of torsion and (2) various methods of increasing the tension-torque ratio and/or narrowing the data spread of the tension-torque relationship. A special torsional attachment was fabricated to attach to a universal testing machine to independently subject rock bolts to combined tensile and torsional loads. It was found that initially installed torsion is nullified during tensile loading and the tensile yield and ultimate strengths are not significantly reduced. Lubricating various components of a bolt assembly or using hardened washers will improve the tension-torque relationship during conventional installation; however, the torsional load is not nullified during this type of loading. Hence, a bolt is subjected to a combined stress throughout the loading cycle; the yield point will thus be lowered compared with the pure tensile yield if care is not taken during installation to stay below the torsional yield.

Jan 1, 1966

By B. Olson, V. A. Marple, D. J. Radet

"Gravitational forces have been found to be an important factor in defining the particle collection efficiency curve of inertial impactors for large particles. In general it was found that if the parameter G = gW /V 0 2 (g is the gravitational acceleration. w is the nozzle diameter and V 0 is the average fluid velocity at the nozzle throat) in greater than 10-3 the efficiency curve would shift to lower panicle sizes. No effect could be seen for lower values of G.IN'IRODUCTIONInertial impactors have long been used as classifiers for airborne particles. By proper design of the nozzles and flow rate it is possible to classify particles with a fairly sharp cut in the particle size range from approximately .02 µm to 50 µm. Because of inertial impactors wide usage they have been extensively studied calibrated and evaluated. Most of these studies have been experimental calibrations of single stages using monodisperse aerosol particles. However, due to impactor simplicity. i.e. a jet of particle laden air impinging upon a flat plate with large inertia particles crossing the streamlines and impacting upon the plate the impactor also lends itself to theoretical evaluation.The most comprehensive method for analyzing impactors theoretically is to use finite difference solutions to the Navier-Stokcs equations and solve for the velocity components and pressure at node points of a grid placed over the area of interest. Using iteration and relaxation techniques the value of the velocity vectors can be determined at these node points with good accuracy. Once the velocities arc known, theoretical particles of known size can be placed into the now field and their trajectories determined by analyzing their equation of motion using numerical methods.Rader and Marple (1985) have performed theoretical analysis on impactors and have included such factors as Ultra-Stoksian .drag and the physical diameter of the particle in their analysis. However, even with these· factors included, there appears to be discrepancy · between the experimental and theoretical results when the particle size is larger than approximately 4 or 5 µm. One possible reason for this discrepancy could be the effect of gravity on the particle as it passes through the impactor. Therefore, a program was initiated to study the effects of gravitational forces on the collection· efficiency of particles in impactors. The results of that study arc presented here."

Jan 1, 1990

By Roy L. Wilfong

Infrared reference spectra are presented of compounds of importance in lead sulfide flotation research. Included are the spectra of several short chain alkyl xanthates of lead and zinc, the corresponding dixanthogen compounds, and the common oxidation products of lead sulfide and their sodium analogs. The spectra of several frequently used industrial flotation reagent xanthates are also presented. A thorough, well-documented discussion is given of the various corrections made to correct the as recorded absorption band data to near absolute values.

Jan 1, 1974

By R. D. Ladoo

"At the beginning of 1920 a general feeling of optimism was noted in many talc-producing districts. The industry seems to have recovered from the temporary depression of the first half of 1919 and many mills are running at capacity production with their entire output for 1920 contracted for. The imports of talc for 1919 were only slightly larger than in 1918 by weight and probably no more by value. Thus foreign competition has not begun to be seriously felt. Several new companies in this country have been organized, some to operate new deposits and others to continue the work done by others.An interesting phase of the present situation is the possibility of increased use of talc in paint. There is a shortage of barium sulfate used as,paint filler. Since, for some uses, talc is considered second only to BaSo4 as a filler for paint, it is possible that part of the shortage could be relieved by an increased use of talc.A series of physical tests upon all pigment materials used in the manufacture of paints is being conducted for the Paint Manufacturers Association of the United States. It is important that all types of talc be represented in these tests. Producers of finely ground talc, 200 mesh and finer, are urged to submit samples of at least two pounds each of these grades that are available to paint makers with trade name and quality data, to the Institute of Industrial Research, 19th & B Streets, Washington, D. C., where the tests are being conducted.The Talc Products Company, Inc., Washington Building, Los Angeles, California, has recently been organized to develop a large body of talc one mile north of Riggs, San Bernardino County, California, This deposit contains a compact, white talc which can be sawed into crayons. The company's mill, at Los Angeles) is equipped with a unit of the Raymond system of grinding and air separation, and pencil sawing machines. It is reported that the pencils are being successfully used in Pacific Coast ship yards.The mining of talc where no mill is owned by the operator and the consequent sale of talc in its crude massive state has not proved profitable in a number of cases recently noted. Under exceptional circumstances, where mining costs are low and the product can be sold to a mill near the mine, the operation maybe profitable, but this condition is not common. One mine of this type has recently closed down, at least temporarily; but a second, more fortunately situated, in another district, is continuing operations, although plans are being made to erect a mill in the early spring. Most satisfactory results are ordi¬narily obtained where the mine and mill are owned by the same company.The sale of the Balmat mine of the International Pulp Company, near Gouverneur, N. Y., to J. H. McLear, Gouverneur, and H. G. McLear of New York, has been reported. It is stated that a large part of the property has been already leased to the Sylvia Lake Company, who will operate it. ""Cement, Hill, and Quarry""* states that ""the first mining done on this property was for silver and lead, but it developed into a good zinc producing property and later it was worked for its talc deposits. It has passed through several hands, the American Pulp Co., the Union Talc Co., and the International Pulp Co., all having had it in successive periods since 1891."""

Jan 1, 1920

By E. C. Perkins

This report describes a ferric chloride trap, based on formation of a low-melting sodium chloride-ferric chloride mixture of near-eutectic composition, and its use in chlorination of impure titaniferous materials. The trap is placed in the hot gas stream between the chlorination reactor and the condenser. Virtually all of the iron is removed by the trap. The condensed titanium tetrachloride is free of suspended solids and contains only a trace of iron. Four examples are given of the use of the ferric chloride trap in chlorination of impure titaniferous materials. INTRODUCTION In the Kroll process, ductile titanium metal is produced by reducing titanium tetrachloride with magnesium metal.4/ In commercial practice, titanium tetrachloride is produced by chlorinating titaniferous materials in the presence of carbon.2/ In 1957 most producers were using rutile, and virtually all plants were designed for its use. About four-fifths of the domestic consumption of rutile was imported from Australia. The Bureau of Mines, under provisions of contract DMP-116 with the General Services Administration, studied electrosmelting of domestic ilmenites and titaniferous magnetites to produce high-titanium slags with pig iron as a byproduct. Under the same contract, chlorination studies also were being made of these slags. Smelting was done at the Northwest Electrodevelopment Experiment Station, Albany, Oreg., and chlorination at the Electrometallurgical Experiment Station, Boulder City, Nev.

Jan 1, 1958