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By Homer J. Ballinger

The Mary Arnold Mining Co. in 194.3 owned 292 acre s of mineral land in Christian County, Mo., and was one of two companies with milling facilities in southern-central Missouri. Production from this property between 19.37 and 1941 amounted to 1,718 tons of zinc in the form of zinc concentrate. Because of the urgent war requirements for additional zinc and the existing facilities for treatment of zinc-lead ores at these mines, in the winter of 1943-44, the Bureau of Mines investigated the deposits by churn drilling in an endeavor to outline enough ore to maintain production of zinc from this district. Five holes aggregating 1,043 feet were bored.

Jan 1, 1948

By S. J. Page, P. Bolsaitls, W. E. Wallace, C. A. Hill, M. J. Keane

"Boiling respirable quartz dust in water for 10 to 40 minutes decreases the cytotoxicity for both erythrocyte hemolytic potential and pulmonary macrophage release of lactate dehydrogenase in vitro. The potential is reduced to near zero in the boiling concentration range of 1 to 10 mg quartz per ml water in boiling times of 20 to 40 minutes. Below this range the detoxification occurs over a longer boiling time. Above this range the hemolytic potential remaining after 40 minutes of boiling approaches native quartz potential with increasing concentration up to 30 mg quartz per ml water. Replacing the media with fresh at the midpoint of boiling results in full detoxification through 20 mg per ml. Pre—boiling the medium with quartz or silica gel reduces the effect of subsequently boiling test samples. Detoxification persists after mild drying at 110 C for 8 hours, and persists after three days of resuspension in water at room temperature. Additional data on persistence of the effect, on the use of acidic and basic media treatment, and on surface analyses are presented, with a discussion of a working hypothesis and research needs.IntroductionResearch underway to determine interactions of quarts and other mineral dust surfaces with pulmonary fluids and alveolar macrophages in culture led to the observation that when dusts were autoclaved in aqueous suspension, their cytotoxic effects on macrophages wore suppressed, in some cases fully and even after several days incubation with the cells. This finding was in direct contradiction to earlier results from both short term macrophage lysosaal enzyme release assays, as well as longer term cytotoxicity assays from macrophages in culture; in those studies, dusts were steam autoclaved at 121 121 ºC with no liquid water but with steam present. (1,2) However detoxification under boiling conditions has been reported in other research.(3). It was decided to use the hemolysis assay to further investigate these findings, because of its sensitivity, simplicity and cost."

Jan 1, 1988

By J. L. Stauffer, L. J. Gaydos, L. M. Demers, D. C. Kuhn

"Eicosanoids and cytokines produced by alveolar macrophages (AM) are key mediators of pulmonary inflammation and fibrosis. In order to determine if eicosanoid production and cytokine production are altered in AM obtained from coal miners, we compared production of prostaglandin E2 (PCE2), thromboxane A2 (TXA2), leukotriene B4 (LTB4), interleukin-1 beta (IL-1B ), and tumor necrosis factor alpha (TNfa.) by cultured AM from normal human subjects and coal miners. The recovery of AM from miners' lungs by bronchoalveolar lavage was significantly greater than that from control subjects. Mean eicosanoid and cytokine production by AM from active miners was also increased compared to AM from control subjects, but this increase was not statistically significant. AM from control subjects produced significantly more TXA2 and TNFa. when exposed to lipopolysaccharide than did AM from miners. The cyclooxygenase inhibitor suprofen reduced PGE1 and TXA1 production and TNF0t. release but had no effect on LTB4 production or IL-1B release by miners' AM. The lipoxygenase inhibitor nordihydroguaiaretic acid attenuated TNFa release, as well as that of LTB4, but had no effect on IL-1B release. Inhibition of thromboxane synthase by UK 38,485 also reduced TNFa release by active miners ' AM but had no effect on PGE1, LTB, production, or IL-1 f3 release. The results of these studies suggest that occupational inhalation of coal dust may increase total lung eicosanoid and cytokine levels and reduce the reactivity of AM to bacterial endotoxin. Furthermore, coal dust-induced changes in both eicosanoid and cytokine release may be subject to pharmacological modulation.The alveolar macrophage (AM) is a primary defensive cell in the lung and is one of the first cell types to encounter inhaled mineral dust. The response of the AM to invading foreign material is designed to enhance the defensive capacity of the lung. However, in the case of occupational inhalation of mineral dust particles, this response may be inappropriate, resulting not in the defense of the lung but in chronic inflammation and fibrosis (Rom et al., 1987; Takemura et al., 1989). The reaction of the AM to chronic mineral dust exposure may involve the exaggerated release of paracrine mediators of lung function, including eicosanoids (oxygenated derivatives of arachidonic acid) and peptides, including cytokines and growth factors (Sibille & Reynolds, 1990). Eicosanoids are involved in bronchial and vascular smooth muscle reactivity, vascular permeability, fibroblast growth, and the recruitment of additional immune cells to the alveolar space (Barnard et al., 1992; Elias et al., 1985; Scott et al., 1982). AM-derived cytokines such as interleukin-1 beta (IL-1 B) and tumor necrosis factor alpha (TN Fa) have a variety of biological activities including the regulation of fibroblast growth and proliferation (Becker et al., 1989; Libby et al., 1989; Schmidt et al., 1984). Interestingly, in vitro studies with macrophages suggest that the production of cytokines may be linked to eicosanoid production, in particular that prostaglandin E2 (PGE2) may down-regulate IL-1 f3 and TN Foe production by the AM (Bonta et al., 1989; Kunkel et al., 1986; Monick et al., 1987)."

Dec 1, 1996

In 2004, a total of 4,401 stone mining operations reported employment to the Mine Safety and Health Administration (MSHA). Stone mines comprised 30.4% of all mining operations.

Sep 1, 2007

By John R. Coulson

Each State and the Federal Government was surveyed for existing certification requirements, the industry yes surveyed for the needs for training blasters, and the training that was available. Recommendations for training and certification for blasters were made.

Jan 1, 1980

By D. M. Soboroff

Etchants containing hexavalent chromium and sulfuric acid are used in a variety of surface-finishing operations. When the resultant spent solutions are discarded, substantial quantities of chromium are lost and pollution prob¬lems are created. To minimize the undesirable environmental effects while improving metal and minerals recycling technology, the Bureau of Mines is conducting research on a method for the economic inplant recycling of these waste etchants. Trivalent chromium, produced when the etchant reacts with a sub¬strate, is oxidized in the anode chamber of a diaphragm cell; other metals, dissolved during the etching operation, are transferred to the catholyte. When waste brass etchants are treated in this manner, all of the trivalent chromium is oxidized and more than 40 percent of the copper and zinc is removed. Similar copper removal and chromium oxidation are achieved with waste printed circuit board etchants and rinse waters from plastic etching operations. The electrical energy needed to regenerate 1 kg sodium dichromate is less than 9 kwhr. Regenerated brass etchants evaluated by two companies equaled or exceeded the performance of fresh etchants.

Jan 1, 1979

By John Campbell, E. S. Baker, G. W. Jones

"INTRODUCTION In previous reports 5,6./ results were given showing the amount of natural ventilation that takes place in manholes (capacities, 74.1 to 308 cubic feet) when the number of ventilation openings in the manhole cover ranged from no openings to a maximum of 4g.The tests warranted the general conclusion that the ventilation or air changes taking place in, a manhole increase as the area of openings in the cover of the manhole is increased, and are proportional (with the exception of a few erratic tests) to the area of the openings in the cover. The area of the openings was the chief factor that affected ventilation.The results did not show any marked change in rate of ventilation due to increased capacity or shape of manhole, when the results were expressed in terms of air changes per day versus area of ventilation openings in square inches per 100 cubic feet of manhole space.It was observed during these investigations that in certain tests that showed erratic results (that is, did not agree with the general average for a given set of test conditions) the wind velocity during the test period was also abnormal. In view of these findings it was decided to conduct a series of tests in which the wind velocity across the openings in the manhole cover could be controlled accurately to determine the effect of wind velocity on ventilation rate."

Aug 1, 1938

By B. J. Dalton

The Bureau of Mines Helium Research Center has developed a computer program for solving two-phase equilibria data for binary mixtures and for evaluating thermodynamic functions of interest, including all critical points. This computer program was used to calculate equilibrium points on the PVTu surface for the helium-nitrogen system as predicted by the Van der Waals equation of state. Numerical values are tabulated and illustrations are presented for 1,279 equilibrium points and for quantities needed to construct Ponchon diagrams. Equilibrium ratios as a function of pressure at constant temperature and of temperature at constant pressure-are also shown graphically. In addition, saturated partial molal volume and partial molal enthalpy data are given. It is shown that the Van der Waals helium-nitrogen system exhibits retro-grade condensation of the second type for liquid helium concentrations of about 0.07 mole fraction or less and pressures below about 45 atm. It is also shown that the critical point is at a -maximum value of pressure (at constant temperature) and of temperature (at constant pressure).

Jan 1, 1971

By James R. FitzSimmons

This report describes an instrument developed by the Bureau of Mines as an improved device for examining roof rock in bolt holes. The unit consists of a commercially available fiberoptic unit adapted for use as a flexible stratascope. Field testing in both metal and coal mines has shown the instrument can be easily transported and used by a single operator. The size and flexibility of the instrument eliminate the need for specially drilled holes.

Jan 1, 1979

By R. C. Hickman

"INTRODUCTION .As part of its spot drilling program, the Bureau of Mines core-drilled seven holes on the Alexander and Barber properties in Spartanburg County, S. C.Extensive surface float and outcrops of sillimanite schist on these properties appeared to justify drilling, which did not prove satisfactory, however, owing to the spotty occurrence of the schist bodies and the poor core recovery in the decomposed schist.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 B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, Oliver C. Ralston, chief, analyzes samples and performs beneficiation tests.This project was under the immediate supervision of Mitchell H. Kline, chief, Raleigh Division, Mining Branch, Bureau of Mines.LOCATIONThe Alexander and. Barber properties are in the southern part of Spartanburg County, S. C. The Alexander property is about 5 miles cast of Woodruff. It is reached from Woodruff by driving east 5 miles on a macadam road to the intersection with an unsurfaced road near Unity Church. The farm house on the property is 0.4 mile north on this road. The sillimanite outcrop is in a field approximately 1,200 feet east of the farm house. The Barber property is about 2 miles north along the unsurfaced road that passes the Alexander property."

Sep 1, 1947

By D. G. Kuehn

Positive ion sampling studies have been conducted on do discharges containing 0.33 percent sulfur dioxide in helium. Measurements were made for normalized gas pressures from 0.45 to 6.8 torr and discharge currents from 5 to 40 ma. Ion species observed included SO+, S+, SO2+, SO3+; O+, and 0+, 02+. Studies were conducted on the functional dependence of the various ion species with respect to axial distance, pressure, current, and gas flow rate. Interpretation of these results is consistent with the assumption of SO2 dissociation. Deposition of sulfur compounds was observed in the plasma container during these studies. The present results are compared with previous studies which have been conducted in SO2.

Jan 1, 1971

By R. O. Dannenberg

A metallic displacement process, utilizing easily available steel wool or steel window screen, was devised and successfully used for the recovery of silver from waste photographic fixing solutions. Laboratory and prolonged commercial-scale testing established that the iron filament type unit will efficiently precipitate silver, as a high-grade sludge, from acidic waste photographic fixing solutions ranging in grade from less than 1 to over 10 grams of silver per liter. Data and design information are presented to facilitate the construction and operation of a practical unit of any desired size. A smelting process for recovering pure silver from precipitated sludge containing 27 to 80 percent silver was devised.

Jan 1, 1968

By T. L. Joseph

The size and accessibility of the Minnesota manganiferous iron ore deposits make them attractive as a potential source of ferromanganese, which is essential in the production of steel. For several years the Bureau of Mines has been conducting experiments to determine the feasibility of producing ferromanganese from these ores by a three-step process which involves (1) the smelting of the ores in the blast furnace to produce a high-phosphorus spiegel; (2) the treatment of the spiegel produced from step 1 in an electric or open-hearth furnace to separate the manganese from the phosphorus and the iron; and 3) the smelting of the high-manganese slag from step 2 to produce ferromanganese. The details of the first two steps of the process and the results of tests with the experimental furnaces have been given in previous reports.

Jan 1, 1931

By C. M. Mason

The current Bureau of Mines active list of permissible explosives includes 95 brands. Twelve are gelatinous and the rest are the more commonly used granular ammonium nitrate type. The list of permissible blasting devices comprises five Cardox models.

Jan 1, 1968

By E. C. Lane

The motor gasoline that is bring marketed in the United States this stunner is slightly more volatile than that sold a year ago. During the past eight years the Bureau of Mines has made semi-annual surveys of the gaoline marketed in the United States, the survey just completed being the sixteenth in the series. The cities in which samples have been collected have been chosen as representative of the more important marketing territories as it is obviously impracticable to obtain a sample of every gasoline sold in the entire country.

Jan 1, 1927

By R. L. Grayson, T. Simonyi, R. A. Andrel

"The purpose or this paper is to disclose analytical, statistical, and observational results relating to mineralogy and trace elements in respirable dust samples collected from two different mines in West Virginia. Samples were taken from longwall panels, and the panels operated in different coal seams, one located in the northern part or the state and the other in the southern region. Mining conditions and equipment arrangements on the panels will be described along with dust control techniques used. Results from sample analyses are summarized with emphasis on relationships between mineralogy, trace elements and mineral particle size to worker locations. Correlations are made between micro x-ray diffraction and energy dispersive x-ray analyses for sample mineralogy.IntroductionThrough the work of many researchers worldwide, the health of coal miners in modern societies is now protected from harmful exposure to respirable coal mine dust. A vast amount of research culminated in the exposure-response model of Jacobsen, et al, (l) which has been used to establish the 2 mg/m3 exposure limit in the United States. According to the model exposure to respirable dust for 35 years at this level or less could prevent the occurrence of a clinically significant case of coal workers' pneumoconiosis (CWP) in a miner. The exposure limit, of course, must be adjusted whenever greather than five percent free silica exists in the respirable dust.The Jacobsen model was built around a mean mass concentration exposure, which generally showed the highest correlation with both incidence and progression of CWP. As Morgan, et al noted, however, the quantity of respirable dust inhaled is not the only significant factor. 2) They noted that although mass of respirable dust correlates highe.st with the incidence of CWP, it is not a causal factor. Admittedly, the insidious processes causing the disease occur at the lund cell-dust particle level."

Mar 1, 1989

By E. G. Valdez

Laboratory research demonstrated that ceramic wall and floor tile can be produced from electric furnace phosphorus slags composed of calcium silicates. Grinding the slag in a pebble mill, followed by magnetic removal of deleterious magnetite, produced a raw material that could be compounded and formed into wall tile by dry pressing, sintering, and glazing. The effects of process variables such as forming pressure and sintering temperature were investigated. Wall tile bodies produced by this method were comparable to commercial tile. The tiles were readily glazed to a smooth shiny finish and met ASTM Specifications C34-62 for structural clay load-bearing tile. The estimated cost of producing wall tile by this method compared favorably with the retail market value for similar wall tile. Addition of borax or other additives to the ground slag followed by dry pressing and firing likewise produced a commercial grade of floor tile.

Jan 1, 1974

By Paul L. Russell

Because of the increasing demand for fluorspar , investigation of the deposits of the Gila district in Grant County , New Mexico , was undertaken by the Bureau of Mines in 1943 with the cooperation of the Federal Geological Survey . It was the purpose of the investigation to assist owners and lessees to develop their properties and to attempt to estimate ore reserves that might be available to supply a 300- ton mill that was under construction at Gila . Field work was begun June 14 , 1943 , and ceased August 16 , 1943. Seven veins were trenched and sampled .

Feb 1, 1947

By Richard L. Rains

In 1984 and 1985, at the request of the Bureau of Land Management, the U.S. Bureau of Mines studied part of the 162,887-acre Mormon Mountains Wilderness Study Area (NV-050-161) in order to evaluate its identified mineral resources. The study area is located in Lincoln County, NV, about 60 miles northeast of Las Vegas. The study area had no mines or mining claims in 1985, and no mineral resources were identified within the study area, or at the Whitmore mine or Iron Blossom prospect near the study area. The alluvial fans around the southern boundary are staked with about 450 placer claims. Chemical analyses of samples indicate that some limestone in the study area is suitable for manufacturing cement or for agricultural purposes but the limestone is distant from markets and therefore not economic in the foreseeable future. The study area is blanketed with oil and gas leases, but no known productive horizons were identified.

Jan 1, 1986

By R. W. Watson

This Bureau of Mines report summarizes some recent results on the sensitivity of various experimental explosive systems using ammonium nitrate (AN) as the oxidizing agent. The sensitivity survey included drop-weight and friction testing and sensitivity to initiation by projectile impact and a No.8 blasting cap. It was found that certain types of AN prills can result in cap-sensitive mixtures when combined with No.2 diesel fuel (Fa); prilled AN mixed with nitromethane also result in cap-sensitive mixtures. Mixtures of AN prills and neat 1-and 2-nitropropane were not cap-sensitive, and the use of powdered or grained aluminum in AN-FO did not adversely affect the sensitivity except possibly to increase its sensitivity to friction.

Jan 1, 1974