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By John R. Shattuck

The Shasta and California Iron-ore deposits are 14 miles northeast of Redding, Shasta County, Calif.; and since 1907 have produced more than 300,000 short tons of exceptionally pure iron ore. Although some ore was mined and smelted from 1907 through the First. World War, most of it has been produced from 1942 through 1945 for use in making heavy ship ballast and concrete anchorages for mines. Irregular masses of magnetite, ranging from lumps of a few tons to pods containing about 25,000 tons, occur associated with skarn near the contact between the McCloud limestone and a younger granitic intrusive. Some of the deposits are low-grade, whereas others are nearly pure magnetite. Selective mining and hand sorting are necessary to produce a high-grade product. Investigation of these deposits by the Bureau of Mines included 2,910 feet of diamond drilling, some surface sampling of the principal mineralized zone and beneficiation tests. Resulting factual data are given in the body of this report.

Jan 1, 1948

By M. Didyk

In this report, the application of the PHU/MVS program is demonstrated through the use of a simple but realistic mine ventilation program. The report details, the problem description, the input data required and the various output features of the simulator. The PSU/MVS program is written in Fortran IV for use with IBM 370/168 computers. A version of the program that can be used in CDC computers is also available. A ventilation network consisting of 531 branches, 300 nodes and 5 fans took 48 seconds for solution on The Pennsylvania State University's IBM 370/168 computer. Appendix I of this report is the User?s Manual for the program. Appendices II and III contain the input data listing, and selected output listing for; the application. Appendix IV provides tables for leakage, friction factors and shape factors.

Jan 1, 1977

By T. J. Ballard

The Ore Knob mine, in Ashe County, N.C., was one of the largest producers of copper in the eastern states during the 1870's. The ore occurs in a fissure vein, which strikes N. 64° E. and dips nearly vertical. The country rock is granite gneiss. Drilling indicated that the vein structure is approximately 200 feet wide and 1,500 feet long. The vein material shows evidence of replacement of the original gneiss by sulfides. Solution cavities in the vein were noted in some places. The ore minerals and pyrrhotite, chalcopyrite, pyrite, and minor quantities of sphalerite. The gangue contains biotite, magnetite, albite, calcite, and many silicate minerals.

Jan 1, 1948

By A. L. Engel

[This report presents results of investigations of problems assigned as ore-testing projects to the Ore-Dressing Section, Metallurgical Division, of the Bureau of Mines at the Mississippi Valley Experiment Station in Rolla, Mo., during the fiscal year ended June 30, 1940.]

Jan 1, 1941

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

"Eicosanoids and cylokines produced by the pulmonary alveolar macrophage (PAM) are key mediators for the defensive role this cell plays in neutralizing the inhalation of particulate dusts and foreign microbes. However, these factors are also mediators of inflammation and their uncontrolled release may cause the lung injury and liorotic changes observed in individuals exposed occupationally to mineral dust. In vitro studies have suggested a link between the production of certain eicosanoids and cylokines released from the activated PAM. To this end, we have studied the release of eicosanoids (PGE2, TXB2 and LTB4) and cylokines (IL-1 and TNF) by cultured PAM, obtained from healthy human volunteers by bronchoalveolar lavage under basal culture conditions and following acute exposure to provocative agents such as the endotoxin lipopolysaccharide (LPS) and mineral dusts including silica. Studies were also carried out in the presence of specific cyclooxygenase inhibitors. The addition of LPS (10 µg/ml) to the culture medium produced a significant increase in PAM release of the eicosanoids: PGE2 (3.5 fold over baseline), TXB2 (2.8 fold over baseline) and LTB4 (4 fold over baseline). LPS also elicited a 2.5 fold elevation in IL-1 from these cells and a 9 fold increase in TNF release. The cyclooxygenase inhibitor, ibuprofen, significantly inhibited the LPS-induced rise in PGE2, TXB2 and TNF but had only a modest suppressive effect on IL-1 release. Exposure of these cells to silica dust elicited a similar augmentation in eicosanoid and cylokine release which was neutralized by prior exposure of the cells to ibuprofen. These results suggest that the enhanced production of eicosanoids and cytokines by PAM exposed to endotoxins and/or mineral dusts may be linked and that inhibition of eicosanoid release is linked to the production of TNF. IL-1 release however is not effectively neutralized by cyclooxygenase inhibition.INTRODUCTIONThe initial pulmonary cellular response to inhaled mineral dust involves the elaboration of potent inflammatory mediators from the pulmonary alveolar macrophage (1). These mediators include the eicosanoids (oxygenated metabolites of arachidonic acid) and cytokines (intercellular peptides) which are released into the alveolar space by the interaction of mineral dust with the PAM surface membrane. The eicosanoids and cytokines promote local nonvascular and vascular smooth muscle contractility changes, elicit the recruitment of additional mononuclear cells into the alveolar space, and enhance the activation, growth and differentiation of lung fibroblasts (2). In this study we sought to examine whether eicosanoid release and metabolism are linked to cytokine release when PAM are activated upon exposure to endotoxin or mineral dusts. Modulation of these pathways through inhibitory pharmaceutical agents may help attenuate the Injurious effects caused by a sustained release of these proinftammatory intercellular factors (3). To that end, we have studied the in vitro effects of endotoxin and silica on eicosanoid and cytokine release from cultured PAM obtained from healthy human volunteers."

Mar 1, 1992

By D. Harrington

The fiscal year which ended June 30, 1932, although one of acute financial de ression was, nevertheless, one of distinct encouragement to those who have long struggled against the much too prevalent occurrence of accidents in coal mines, especially of coal mine fire and explosion dis- asters, both of which are now known to be readily preventable. Table 1 summarizes some important information about explosions in the United States coalies for the fiscal year which ended June 30, 1932, insofar as such information is available to the safety division of the United States Bureau of Mines, the personnel of which are under instruction to get in touch with and report on all mine explosions in their respective districts, including not only those occurrences with loss of life but also those in which for- tunately no lives, are affected. Table 1 gives data on 33 ignitions in 10 States with a total of 87 deaths for the year; the number of ignitions (33) is considerably groater than the number (26) for the previous fiscal year, and is exactly the aver- age number for the past four fiscal years; the mumber killed in the 33 ignitions (57) is materially lower than that (217) for the preceding fiscal year or the average (150) for the past four fiscal years. The States with the greatest number of deaths from explosions in the fiscal year ending June 30, 1932, were Virginia; 54; West Virginia, 11; Pennsylvania, 7 (6 being in anthracite mines); Alabama and Colorado, 4 each; Illinois and Kentucky, 3 each; and Maryland, 1. The greatest number of ignitions listod wes that for West Virginia, 7; then came Pennsylvania with 6 (2 being in anthracite mines); Alabama with 5; Colorado, Illinois, Tennessee and Virginia, 3 each; and California, Kentucky, and Maryland, 1 each. The 1931-32 record as given in Table 1 includes several States which were not listed in the previous year: Colorado, Kentucky, Maryland, Tennessee,

Jan 1, 1933

By P. D. Kovscek

The Bureau of Mines has tested a low-thrust water-jet-assisted rotary drill. This work was performed to evaluate the performance of a water-jet-assisted drill operated at thrust levels typical of a handheld manual-thrust operation. Prior work by the Bureau had indicated that using water-jet assist with high-thrust drilling applications would increase drilling rate. Small-diameter holes were drilled in five different types of rock. Thrust and water pressure were varied as the drill rate was monitored. The test results indicate that drilling rates increase with increasing water pressure and thrust. The water jet has more effect on reducing the specific energy when drilling in the harder rocks than in softer rocks. Variation in drill rate for a given rock sample is attributable primarily to the material heterogeneity within the sample. One rock type (Greenwich sandstone) could not be drilled efficiently with the water-jet-assisted drill.

Jan 1, 1988

By A. S. Moore

The Bureau of Mines is doing research and development work on removing acid-gas impurities from synthesis gas made directly from coal. Since conventional gas scrubbers, packed towers and bubble-cap columns, are expensive to construct and difficult to operate with viscous solutions, one aspect of the work was developing a compact, agitated, gas-liquid contactor for use with concentrated absorbents. The efficacy of the agitated contactor for absorbing carbon dioxide in diethanolamine increased with increasing solution rate, turbine speed, diethanolamine concentration, and carbon dioxide concentration in feed gas, and with decreasing liquid-gas ratio. It was unaffected by pressure between 200 and 300 p.s.i.g. and little affected by temperature between 115 and 190° F.

Jan 1, 1961

In conjunction with steady increases in production levels, longwall operators have applied greater quantities of ventilating air and spray water in an effort to control respirable dust and/or methane. Air velocities greater than 7.6 mls (1500 fpm) have been measured on longwall faces. Operators have expressed concern over the potential entrainment of respirable dust at these high velocities. The greatest likelihood for entraining dust into the high velocity airstream may occur as shields are advanced allowing relatively dry particles to fall from the shield canopy directly into the airstream. Laboratory tests to simulate dust liberation during shield movement were conducted at the Pittsburgh Research Laboratory of NIOSH at velocities ranging from 2.0 to 8.2 m/s (400 to1600 fpm). Airborne dust samples were obtained with personal impactors to quantify the size distribution and concentration of the dust entrained at the various air velocities. Statistically significant increases in both total and respirable dust concentrations were measured as test air velocities were increased.

By H. L. Bibbs, H. D. Snedden

"INTRODUCTION The use of beryllium and its alloys has increased rapidly during the last decade. Further expansion of its use is limited; in part, by lack of adequately developed ore reserves. The principal commercial beryllium mineral is beryl, which is found chiefly in pegmatites and produced for market as a byproduct of the mica and feldspar industries. The coarse beryl is mined selectively, sobbed and sorted by hand, and then sold without further beneficiation. The known reserves of coarse beryl are small. No method has been available for concentrating small disseminated beryl crystals, so ores of this type have not been mined or have been left on waste dumps. Disseminated ore in low-grade unmined areas and waste dumps on developed properties is a potential source of beryl, provided a method is developed for its beneficiation.Published literature on the concentration of beryl is lacking in detail or deals chiefly with tests on artificial mixtures of pure minerals, and procedures as given were not applicable to the beryl ores tested at the Salt Lake Station. The testing procedures described in this report are independent developments. By employing these procedures, beryl was satisfactorily con¬centrated from several run-of-mine and dump ores, although these ores wore low in grade and part of the contained beryl was finely crystalline and disseminated.Beryl, quartz, and feldspar, when ground to flotation sizes, are so alike in color and general appearance that they cannot he distinguished by visual observation. The progress of the work depended on rapid determination of the grade of test products by means of the petrographic microscope. Small samples of concentrates and tailings were often cut after each addition of reagents, dried, and examined under the microscope."

May 1, 1947

By D. Ng

A facility to evaluate the fire endurance of mine stoppings was constructed by the Bureau of Mines in the multiple entry section of the Bruceton (PA) Experimental Mine. Stoppings up to 6 by 18 ft can be tested in a manner simulating mine conditions. The stopping is subjected to a 70-min liquid fuel tray fire with an energy output of 75,000 Btu/min. The stopping and adjacent areas are instrumented with thermocouples and heat flux gauges. Data acquisition is by an automatic data logger capable of continuously recording over 100 channels of information. Two 8-in-thick concrete block stoppings and a galvanized steel stopping were tested. A crack developed on the fire side surface of the block stoppings where the flames were most intense. However, the temperatures of the unexposed surfaces of the stoppings never exceeded 800 C and the surfaces were undamaged. The steel stopping retained its structural integrity during the test. The temperature of the unexposed steel surface reached 5000 C, but combustible materials located 1 ft from the surface did not ignite. A 3/4-in-thick coating of construction plaster was applied to the fire side of the previously tested uncoated steel stopping. The quantity of heat energy transmitted across this coated metal stopping was reduced approximately 50%. All stoppings prevented the passage of flame and smoke.

Jan 1, 1988

By H. E. Powell

The magnetic susceptibility, the geographical source, and associated minerals are given for 44 copper-, 26 lead-, and 19 zinc-bearing minerals. Of the 44 copper minerals/ all had a susceptibility of less than 15 X 10-6 cgs, and about 20 percent of them were diamagnetic. Of the 26 lead minerals, all had a susceptibility of less than 11 X 10-5 cgs, and almost half of them were diamagnetic. And, of the 19 zinc minerals, all except four had a susceptibility of less than 9 X 10-6 cgs, and about one-fourth of them were diamagnetic.

Jan 1, 1968

By Nunna Malakondaiah

Plant samples collected from the mined sites of Beulah, Center and Zap and the test sites of North Beulah 1, North Beulah If, South Beulahh and Center were analyzed for their nutrient concentrations. The vegetation from the mined areas generally showed lower concentrations of Na, P and Cu and failed to meet the nutritional requirements for beef cattle as defined by National Research Council (minimum requirements are: Na, 600; Cu, 4; P, 1800 µg/g dry weight). Plants from Beulah showed generally higher concentrations than from Center or Tap. Tissue concentrations of K varied significantly between sites for 5 species due to the low tissue concentrations at Center. Deficiencies are difficult to isolate as the sampling was done in mid-summer and generally during that season the tissue concentrations tend to decrease in several species. All of the plant species at the unmined sites, with the exception of western wheatgrass at Zap, had lower concentrations of P than the minimum nutritional requirements for beef cattle. Sodium concentration was low but Cu was marginal to adequate in plant species at the unmined sites. Concentrations of K, Mn and Cu in western wheatgrass were greater at Center than at Zap while the opposite was true of the concentrations of Zn, Cu and P in blue grama and Cu in green needlegrass. Amending the spoil with slack at North Beulah I decreased the concentrations of Zn, Cu and P in wheatgrasses grown on spoil from 0-2, 5-10, and 20-25 foot depths, respectively. In general, the mean tissue K+/Na+ ratios were greater in plants on slack amended spoils, primarily due to the reduced Na concentrations in the tissue. At North Beulah II test site, only wheatgrasses grown on spoil amended with slack showed significant increase in K and decrease in Na and Mn concentrations. At South Beulah test site which received 12" topsoil over graded spoil, leonardite amendment decreased P concentrations in all of the grasses as compared to control, whereas fertilizer treatment increased the same. Nutrient concentrations were lower in both fescue and needlegrass with leonardite treatment and higher with fertilizer treatment although not significantly different from control. The concentrations of Ca, Mg, Na, Fe, Cu and N in grasses grown on topsoil at Center test site were significantly higher than on slack amended spoil. Legumes grown on topsoil at Center site contained higher concentrations of P than those grown on spoil; there were no significant effects due to slack on spoil or topsoil. The data presented in this report act only as an indication of between-treatment and between-species differences in tissue composition of plants harvested in mid-summer season. With respect to the nutrients analyzed, since none were found to be toxic, the cattle can safely feed on the vegetation of these mined areas.

Jan 1, 1982

By Andrew M. Leszcykowski

The Bureau of Mines (Bureau) conducted mineral investigations of the Payette Crest-South Fork area in west central Idaho near McCall, Idaho, in 1989. There are no known producing mines or mineral production from the area. Forty-seven samples were taken (stream sediment, rock. and placer); no identified mineral resources were delineated.

Jan 1, 1991

By William E. Eckard

Production of oil from a narrow shoestring sand presents problems unique in the oil industry. Especially important, from both an engineering end an economic standpoint, are the limitations imposed upon well patterns and spacings by the shape of the field. This report concerns a study of the Paola shoestring, Miami and Franklin Counties, Kane., where well density of 0.85 acre per well was not uncommon to insure profitable primary recovery in a reasonable time. However, such a great number of wells increased the operator's investment and reduced his profit considerably. It was the purpose of this study to investigate various well patterns and spacings applicable to water-flooding a shoestring reservoir and the effect of these factors upon recovery of oil and the most profitable operation of the pool. The designer of well patterns for a shoestring sand should evaluate carefully the edges of the shoestring, even though they may be considered too thin to drill. These comparatively thin edges contain large quantities of recoverable oil; moreover they are resaturated with oil as the pool is water-flooded.

Jan 1, 1951

By J. J. Demeter

Experiments were conducted in 2- and 4-inch-diameter standpipes to evaluate the effectiveness of standpipes as pressure seals. During the experiments, these standpipes conveyed Alan-Wood magnetite (60 to 230 U.S. standard sieve mesh) by gravity flow from one vessel to another of relatively higher pressure. The information obtained has been helpful in a Federal Bureau of Mines investigation of how to make either synthesis gas or hydrogen by a modified steam-iron process employing a continuous recycling stream of granular iron-iron oxide at temperatures of 600° to 900° C. In this process the mixture of granular material flows by gravity from a reduction vessel at low pressures to an oxidation vessel at higher pressures. Data from the 2- and 4-inch-diameter standpipes indicate that it would be practical to use a standpipe as a pressure seal between the reductor and oxidizer. Investigators found that, by gravity flow, the standpipe could convey the Alan-Wood magnetite against pressure gradients up to 1.07 pounds per square inch per foot of column height.

Jan 1, 1961

By B. J. Scheiner

The Federal Bureau of Mines investigated an electrolytic oxidation procedure for extracting lead, zinc, copper, and silver from lead-zinc concentrates. Concentrates slurried in brine were pumped through the anode compartment of electrolytic cells equipped with selective ion diaphragms. Hydrochloric and hypochlorous acids generated in the anode compartment converted the metal sulfides in the concentrates to soluble metal chlorides, sulfate ion, and elemental sulfur. Metal extractions of 92 to 100 pct were obtained from lead-zinc concentrates at an energy consumption ranging from 1.5 to 5.0 kW-hr/lb metal extracted. Sodium hydroxide was formed in the cathode compartment at a current efficiency of >99 pet. Silver and copper were extracted from refractory tetrahedrite minerals, but the process entailed a relatively high energy consumption. Sealing the top of the diaphragm cell utilized the chlorine more effectively, thereby reducing energy consumption 10 to 50 pct.

Jan 1, 1975

By Harry Perry

One of the most notable achievements of the iron and steel industry in the United States in this century has been the general increase in productivity of individual blast furnaces and the reduction in coke rate. Most of the improvement in furnace operations has occurred within the past decade. During this time the output of the average furnace increased about one-third, while fuel rates decreased from 15 to 20 percent. For example, in 1949, the iron and steel industry produced 811.2 short tons of pig iron per blast-furnace day with a coke rate of 1,870.4 pounds per ton of pig iron, By 1960, the average production of pig iron per blast-furnace day had risen to 1,182.4 tons, while the coke rate had decreased to 1,497 pounds per ton of pig iron. These figures are averages for the entire industry; many furnaces produced over 2,000 tons per day and one furnace, operating on pellets, reached 2,700 tons of pig iron per day, Coke rates of individual furnaces varied, but some furnaces operated on less than 1,200 pounds per ton of pig iron. The significance of this decrease in coke rate is shown clearly when data on pig-iron production and coke consumption in 1959 are compared with 1948. In 1948, 57.3 million short tons of coke was charged into blast furnaces to produce 60.1 million tons of pig iron; in 1959 only 47.6 million tons of coke was needed to produce 60.2 million tons of pig iron. Thus, in 1959, nearly 10 million tons less coke was required to produce about the same amount of pig iron as was produced in 1948.

Jan 1, 1962

By A. B. Hooker

Nineteen of the installations were on rental contracts 1.L."'1der whtch the lamps belong to the lamp company and are rented by t.½em to the mine operatj.nt; company. · The other nine installations had been upon an O\Vnership-rental basis, by which the lamps had become the property of the renter at the end of 5 years. Five of t.11e rentec installations were en a special contract calling for a guaranteed light output. These contr2.cts were based upon certified . initial performance, with the provision that the lamps be replaced whenever periodic tests of fully charged lamps, taken at random from t..h.e charge racks, showed a light output of less than 80 percent of the certified performance.

Jan 1, 1942

By T. H. Jeffers

The Bureau of Mines conducted laboratory tests to devise a procedure for extracting copper from low-grade discarded mill tailings. A solid extractant consisting of an organic solvent extraction reagent adsorbed on granular activated carbon was investigated and proved to be satisfactory for extracting copper directly from leach pulps. When this material was used in a cyclic leaching, stripping, and electrowinning pro-cess, 95 pct of the acid-soluble copper was recovered from oxidized mill tailings. The weathered tailings contained 0.24 pct Cu (total) and 0.20 pct acid-soluble Cu. The copper was recovered as cathodes containing, in parts per million, 1.6 Pb, 3.6 Fe, 0.5 Sb, 1.5 AI, 1.9 Mn, and <1 Mg.

Jan 1, 1985