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By E. P. Youngman

This paper is one of a series of digests of foreign mining legislation and court decisions that is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to can and ore rate mines in various foreign countries. This interpretation of the mining laws of the Irish Free State has been prepared from the best available material in Washington and is released subject to amplification and correction, if necessary, by American foreign-service officials. INTRODUCTION This paper is based upon the mines and minerals act, 1931, enacted by the Legislature (Oireachtas) of the Irish Free State (Saorstát Eireann), December 22, 1931, the lull title of which is "An act to establish a board to perform functions in relation to mines and minerals, to authorize the making of lenses of mines and minerals belonging to or vested in Saorstát Eireann, to name provider for facilitating the working of other mines and minerals and, for imposing restrictions on the working of minerals required for the support of buildings and works, to amend the law with respect to mines, and for other purposes incidental to the matters aforesaid.'

Jan 1, 1933

By Bruce D. Hanson

The Bureau of Mines conducted a series of ignition tests with two types of conical bits (plumb bob and pencil) used on continuous mining machines, to determine their ignition potential at various bit speeds, cut depths, and wear conditions. The tests were conducted using single bits mounted on a 34-in-diam drum in a Bureau ignition test facility. The bits impacted blocks of Berea sandstone in a 6.5 pet methane atmosphere at various bit speeds and cut depths. In a new condition, the plumb bob bits were considerably more incendive than the pencil bits, causing ignitions in 32 of 35 tests at 60 rpm, compared with ignitiolls in 2 of 22 tests for the pencil bits. The results from new bit testing also show that reduction of bit tip velocity to 180 fpm does not eliminate ignition potential. When subjected to progressive wear, bits of both types were more incendive when they were locked in place, unable to rotate, than when they were free to rotate.

Jan 1, 1983

By K. C. Dean

Time and motion studies were made by the Federal Bureau of Mines on the hand and machine dismantling of scrapped auto starter motors, generators, and alternators for recovery of copper, aluminum, and iron. The studies showed that an individual with power handtools and convenient access to a hydraulic press, power bandsaw, acetylene torch, and power lathe could, in an 8-hour day, disassemble about 100 starters, or 150 generators, or 30 alternators. The scrap copper yield would be 280, 390, and 45 pounds, respectively, and the iron yield would be about seven times the copper weight. About 100 pounds of aluminum would be obtained from the alternators.

Jan 1, 1976

By Henry G. Dorsett

This report is a description of equipment and test procedures used by the Federal Bureau of Mines in laboratory studies on the explosibility of dusts. The principal tests concern ignition temperature, minimum explosive concentra¬tion, minimum electrical energy for ignition, limiting oxygen concentration, pressure, and rates of pressure rise. As new materials often present unique problems, variations in the general procedure and special tests performed are indicated, The general procedures for handling a dust sample from its receipt at the laboratory to the preparation of the report are described. The repro¬ducibility of the respective tests are shown. A brief history of laboratory studies on dust explosions by the Bureau of Mines and a description of current equipment and test procedures used are presented in this report. Its purpose is to facilitate interpretation of data previously published and those proposed to be published on the numerous mineral, agricultural and industrial dusts that have been studied. Through understanding and interpretation of the laboratory data obtained for the parameters of explosibility, preventive measures can be adopted for alleviat¬ing the hazard of dust explosions arising in manufacturing and processing industries.

Jan 1, 1960

By Richard Havens

A flotation procedure was devised by the Federal Bureau of Mines for beneficiating Mount Wheeler, Nev., beryllium ores that contain the beryllium minerals bertrandite and phenacite in a complex association with calcite, fluorspar, mica, quartz, and other accessory minerals, The method also has proven to be effective in trials on ore from the Lake George, Colo., area. Samples used in most of the research ranged from 0.49 to 0.73 percent BeO. Beryllium mineralization varied from two-thirds bertrandite to all phenacite. An unusually high grade sample containing 5 percent BeO as phenacite was floated on a batch basis to prepare concentrate for utilization studies. The beryllium minerals were floated from undeslimed pulps at natural pH using sodium fluoride and sodium hexametaphosphate (HMP), as modifiers, and a fatty acid-fuel oil combination as the collector. Key factors were the use of a minimum of about 4 pounds of sodium fluoride and between 2 and 4 pounds of HMP per ton of ore. Efficacy of the HMP was related to the grind, mineralogical composition, corollary reagents, and type and time of conditioning. Addition of the fluoride, HMP, and collector in that order, followed by appropriate conditioning after each addition, was essential for satisfactory flotation.

Jan 1, 1961

By N. S. Dalal, X. Shi, V. Vallyathan

"Electron spin resonance (ESR) and cytotoxicity measurements were made on newly fractured silica to examine specifically the role of the fractured-induced, siliconbased radicals (Si· and SiO·), and silica-generated hydroxyl (·OH) radicals in the mechanism of the cell membrane damage by silica. The concentration of the Si· and SiO· radicals was controlled through decay processes, thermal annealing, and boiling, while that of the ·OH radicals was varied by using catalase, superoxide dismutase, KMnO4, Ha2seO3, ascorbic acid, and metal ions, and monitored via ESR spectroscopy. The dust's cytotozicity potential was evaluated by measuring the silica-induced hemolysis and also by determining lipid peroxidation (using linoleic acid). Prom the comparison of hemolysis and ESR results it is deduced that the radicals play little· or no role in the silica-induced hemolysis. However, the lipid peroxidation data indicate that the radicals might be involved in the initiation of an oxidative chain reaction leading to the macrophage membrane damage through lipid peroxidation. INTRODUCTIONThe biochemical mechanism of Quartz-related pneumoconiosis is still not fully understood. It is believed, nevertheless, that one event of primary importance is the perturbation of cell membranes by the dust particles (Allison et al., 1966; Allison and Harrow, 1971; Bateman et al., 1982; Parazzi, et al., 1968; Reiser and Last, 1979; Shi et al., 1989; Summerton et al., 1977). The ensuing cell-membrane damage unleashes certain lytic enzymes resulting in additional cell injury and eventual fibrosis (Nolan et al., 1981; Summerton et al., 1977). Thus considerable effort is currently being made towards the understanding of the processes by which quartz particles disrupt the membrane of a red blood cell (RBC) or a pulmonary alveolar macrophage (PAM). A simple but important method of evaluating the membrane damage potential of a dust is the hemolysis test (Harington et al., 1971). Even though this test is used routinely for screening dusts for their cytotoxicity potential, the biochemical mechanism underlying the cell lysis by many dusts, including quartz, is still controversial (Kilroe-Smith, 1974; Singh and Rahman, 1987), and this provided us the impetus for the present undertaking."

Jan 1, 1989

By G. L. Neumann

The Andover-Sulphur Hill iron mines in Sussex County, N. J., have a production record extending over 100 years. The last production recorded was about 1880. These mines produced high-grade ore of two types: Bed ore (hematite) and blue ore (magnetite. Some sulfides (lead, zinc, and copper) were found underlying the iron deposits. Data as to size and grade of these sulfide bodies are very sketchy, Toward. J. Hewitt of Elizabeth, N. J., lessee of the Sulphur Hill mines from 194045, prospected for lead, zinc, and copper. .His Only production was several hundred tons of low-grade iron ore, which was crushed and used as heavy aggregate to make concrete blocks for ship ballast. In October and November 1942 made a magnetic survey of this area and bored six-diamond-drill holes with the dual objective of prospecting for sulfides and testing for extensions of the iron-ore deposits indicated by the magnetic survey. In 1944, an iron-mining company examined this property and diamond-drilled seven holes Between December 1949 and March 1950, the Bureau Of Mines in search of sulfide deposits, bored three additional diamond-drill holes. Two of these were on the Sulphur Hill tract and one on the adjoining Tar Hill tract.

Jan 1, 1952

By J. B. Ligon

Blast induced stress waves, propagating along the surface of a drift of an underground hardrock mine, were recorded and analyzed. Resistance strain gages, accelerometers and a velocity pickup were used in making the measurements. Although a full face blast was recorded, the stress waves were initiated by single borehole blasts for the majority of the project. A special instrument trailer was designed, constructed and utilized during the project. A reliable strain wave transducer was developed for measuring the stress waves propagating on the drift surface. A correlation study between strain and acceleration signals for P-waves was made which agreed well with theory. The use of stemming was found to reduce strain and acceleration magnitudes as predicted.

Jan 1, 2011

By D. D. Fischer

Recovery and separation of molybdenum and rhenium from a process solution was accomplished by a technique developed by the Federal Bureau of Mines involving a combined solvent extraction and activated carbon adsorption procedure. The processing sequence required treatment of the solution with S02 to reduce the chlorate ion and adjust the pR prior to solvent extraction of molybdenum and rhenium with a tertiary amine. Molybdenum and rhenium were stripped from the organic phase with an NH40H solution, and the strip solution was then passed through activated carbon to preferentially adsorb the rhenium. After washing entrained molybdenum from the column with a brine solution, rhenium was eluted with an MeOH-H20 mixture. The activated carbon was regenerated with water. Molybdenum was recovered as (NH4)6Mo7024 by evaporating the column effluent. Rhenium in the column eluate was reextracted with a tertiary amine, stripped from the organic phase with dilute NH40H, and recovered as NH4Re04 by evaporating the strip solution. The final (NR4)Re04 product contained < 80 ppm impurities. Sodium sulfate was crystallized from the first solvent-extraction raffinate by lowering the solution temperature to 0° C. Precious metals contained in the original process solution were adsorbed onto the activated carbon.

Jan 1, 1975

By Ani Chitaley

A new method has been developed for handling supplies in underground bituminous coal mines. A survey indicates industry wide implementation potential for the proposed method. Reduction of supply handling accidents&apos; by as much as 73% and improvements in the productivity of face operations by at least 3% are anticipated benefits. The new method is based on the palletization of daily supplies and the use of a forklift for carrying out the handling tasks at the underground section. A prototype of the forklift has been delivered to the U.S. Bureau of Mines. The forklift has demonstrated several important features necessary for underground supply handling such as compactness, maneuverability, visibility, ease of control and auxiliary attachments for hoisting, carrying timber and pulling. Design improvements are recommended for future generation underground forklifts. These relate to higher speed, increased battery duty cycle, higher payload and modified traction/steering to eliminate plowing of soft mine floors.

Jan 1, 1983

By Martin H. Stanczyk

Acid leaching of selected copper sulfide minerals, impure copper sulfide flotation concentrates, and a cement copper precipitate at elevated temperatures and pressures was investigated. Copper extractions of 97 to 99 pct were obtained by leaching chalcopyrite and the flotation concentrates with water under oxidizing conditions at 200° C for 30 to 60 min. In tests with bornite, chalcocite,and cement copper, addition of sulfuric acid or pyrite to the autoclave was required to obtain similar copper extractions. The chemistry of leaching copper minerals was studied. It was determined that different copper sulfides altered to covellite as one step in their dissolution.

Jan 1, 1963

By Thomas A. Phillips

The Bureau of dines present, an economic evaluation of its process for the ferric chloride leaching of chalcopyrite concentrate. In this process, chalcopyrite concentrate is leached with ferric chloride solution to extract copper, which is precipitated from the solution by electrolysis while leaving sulfur in the residue. Spent liquor from electrolysis is treated with oxygen to regenerate the ferric chloride leach solution and the sulfur-laden residue is processed to recover the sulfur. A cost estimate was prepared for a plant capable of processing 600 tons of chalcopyrite concentrate per day, 330 days per year. The fixed capital cost, on an early 1.975 basis is $27,831,600 and the estimated operating cost is 9.9 cents, per pound of copper product. In comparison, the estimated operating cost of a smelter equipped with a citrate process plant to recover sulfur is about 13.6 cents per pound of copper product. No charge for chalcopyrite concentrate or credit for recovered byproducts has been included in either operating cost. The ferric chloride leach process, therefore, appears to be economically attractive.

Jan 1, 1976

By P. L. Woolf

Two blast furnaces, one a. commercial furnace and the other the Bureau of Mines experimental furnace, were successfully operated with extremely low slag volumes. The lowest slag rate obtained on the industrial furnace was 335 pounds per ton of metal. Using the same burden materials a 245-pound slag volume was achieved on the furnace. The coke rate saving and increase in productivity resulting from lowered slag rates are discussed as well as the factors limiting a low slag practice.

Jan 1, 1965

By A. L. Engel

Simple treatment methods, employing the least possible equipment, can sometimes be established for marginal ores and economical results achieved. In continuation of a long-established part of the hydrometallurgical and ore-dressing program of the Reno Station of the Bureau of Mines, typical ores from newly discovered or recently explored mining districts have been investigated. The purpose of such investigations is to encourage the search for and development of mineral resources and particularly to assist in the economical exploitation of low-grade and marginal ores, as well as the conservation and recovery of values in products from former operations that were discarded because of past inability to treat them economically. Several of these investigations have been limited to preliminary tests of samples from prospecting operations, whereas some involved samples of old dumps or tailings piles. The test, work in these cases was not extensive enough to warrant publication as individual reports, but is of considerable interest inasmuch as it indicates the possibilities as well as the limitations of treating the respective materials; and because, inasmuch as the samples were representative of the districts from which they were obtained, this in-formation should be helpful in the future development of these districts. The present report is a compilation of results of brief preliminary tests on oxide ores only, which contained gold and silver and in some cases base metals. The methods of treatment used include gravity concentration, amalgamation, flotation, and cyanidation. For the most part, only standard laboratory procedures were employed. No attempts were made to develop new methods for the low-grade refractory ores in this group of samples if simple treatment was not successful, as the stage of development of the properties did not warrant extensive experimentation on the samples submitted.

Jan 1, 1951

This U.S. Bureau of Mines (USBM) report conveys the results of an economic analysis of minerals in the West Mojave Management Area (WMMA), including the Desert Tortoise Priority Habitat (DTPH), a proposed special land management area. Undiscovered mineral resources were estimated for the entire WMMA, which totals 8.7 million acres. Known mineral resources were studied for the DTPH, which is an area of 1.2 million acres contained within the WMMA. Federal lands within the WMMA are managed by the Bureau of Land Management (BLM). The WMMA includes Federal, State, and private lands in the western portion of San Bernardino County and the eastern portion of Kern County. The center of the study area is 20 miles northwest of Barstow, California (Figures 1 and 2).

Jan 1, 1993

By J. E. Matta

The Bureau of Mines made laboratory absorption measurements on oil shale samples, which showed that the amount of methane absorbed is proportional to pressure and oil yield, and can be much larger than would be predicted based solely on porosity. Oil shale cores collected in the field were also measured for their gas content using the Bureau of Mines direct method. Cores taken from deep locations and far from outcrops yielded more gas than cores from shallower locations or at outcrops, when taking into account variations in oil yield, and all data indicate that oil shale mines that are both deep and far from an out-crop will emit low levels of methane gas.

Jan 1, 1977

By J. A. Stampe

In connection with its investigations of strategic minerals in the United States, the Bureau of Mines ran magnetic surveys totaling more than 533,000 linear feet at 30 deposits of magnetite in northern New Jersey. These deposits occur in a belt of granitic gneiss and in limited areas of limestone. The ore consists of magnetite accompanied by score of the following minerals: Hornblende, augite, apatite, feldspar, biotite, calcite, garnet and pyrolusite. Results of these investigations are being presented in two reports of which this is the second. The first paper, Certain. Magnetite Deposits in New Jersey, by A. L. Neumann and McHenry Mosier, was issued in April 1948 as Report of Investigations 4225.

Jan 1, 1949

By F. W. Lane

Some months ago the Bureau of Mines began research of a fundamental character on sulphur in petroleum. In the course of this work, the usual qualitative test for sulphur in organic compounds1 was applied to certain oils that were believed to contain approximately 0.5 percent sulphur. No sulphur was found, and, as a check on the qualitative test, the oils were subjected to quantitative determination of this element by the oxygen-bomb method.2 The sulphur content of the oils ranged from 0.10 per cent to 0.50 per cent. This experience led to further trial of the qualitative test for organic sulphur, both on the oils mentioned above, and on common sulphur-containing organic substances. No difficulty was experienced in detecting the element in the latter, but with the petroleum oils the test, as usually performed, could not be relied upon to detect less than 0.60 per cent of sulphur consistently. The use of mechanically polished pure sheet copper for the detection of free sulphur, hydrogen sulphide, and perhaps other sulphur compounds has been recommended.3

Jan 1, 1927

By Peter Grandone

Steel and iron pipe lined with cement to protect it against corrosion has been used in the municipal water systems of the New England States since about 1870. In most recent years, the petroleum industry adopted cement-lined pipe to forestall corrosion, particularly in those areas where large quantities of corrosive brines and hydrogen sulfide are associated with the oil produced. Many of the oil companies had on hand large quantities of corroded pipe, normally disposed of as scrap, which could be cleaned, lined with cement, and returned to service. It was soon learned that after the so-called scrap pipe was lined with cement much of it could serve fully as well as new cement-lined pipe. The demand for lining used pipe with cement resulted in the establishment of several processing, plants in the Mid-Continent oil-producing area. Today six cement-lining plants serve the areas three in Oklahoma and one each in Kansas, Texas, and Illinois. All of these plants have lined large quantities of used pipe for the brine-disposal systems of western Kansas, Illinois, and east Texas and also for the operators of water-flooding projects in northeastern Oklahoma and southeastern Kansas, where large quantities of brine and fresh water are being injected into the oil-bearing formations as a secondary oil-recovery method. Since war demands during the past 2 years have created an acute shortage of steel, the need of reclaiming used pipe for the expansion of oil-producing operations has become more evident than ever before. Thus the new industry (about 6 years old) - lining used pipe with cement - is saving large quantities of steel at a critical time by reclaiming used pipe and preventing further- corrosion.

Jan 1, 1945

By C. J. Chindgren

Two air classification systems were built and tested as separatory devices for recovering the nonferrous metal values from shredded automotive nonmagnetic reject scrap. A horizontal air system with a capacity up to 16 tons per hour was used to obtain preliminary separations, and a smaller capacity vertical system was used as a cleaning device. Shredded automobile reject material containing aluminum, copper, and zinc values of about $55 per ton were air-classified in the horizontal elutriator. Ninety-six percent of the metal was recovered in a 74-percent metal concentrate. Tandem operation of both classifiers recovered 92 percent of the metal in an 80-percent concentrate while rejecting 87 percent of the nonmetallics. Heavy media separation of the air-classified concentrate produced an overall recovery of 91 percent of the metal in the form of a 99-percent metal concentrate.

Jan 1, 1971