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By Travis Q. Lyday

Gold continued to dominate mineral production in the group of volcanic islands and atolls of Melanesia in the southern Pacific Ocean, which comprise the British Commonwealth nation of Fiji. The Fijian mineral sector, however, remained of minor importance in terms of export earnings, Government revenues, and employment to the economy of the country, which was primarily agrarian with sugar as its mainstay. The Vatukoula gold-silver mine on the north side of the main island of Viti Levu remained the largest and most important mining operation, as well as Fiji's only operating metalliferous mine. In October, Western Mining Corp. (Fiji) Ltd. (WMCF), a wholly owned subsidiary of Australian-registered Western Mining Corp. Holdings Ltd., increased its interest in the Vatukoula joint venture from 10% to 20% by exercising its option with Emperor Gold Mining Co. Ltd., also of Australia. The assumption of mine management operations at Vatukoula in 1983, with its attendant influx of additional capital and technological expertise, enabled WMCF to increase both efficiency and output at the mine during 1984. Higher output was obtained owing to an increase in underground ore production, which was partly offset by a reduction in opencut tonnage, as well as to modifications in the recovery circuit. Rate of recovery increased from about 15% to over 82% of the gold contained in the ore and from about 40% to 45% of the contained silver.

Jan 1, 1986

By J. E. Spurr

"Zinc Industry in BelgiumBy March F. Chase, Consulting Metallurgist, Bureau of MinesBelgium for many years was the principal spelter producing country of the world. Gradually its production was surpassed by that of Germany, and Germany in turn lost first place by the production in the 77ti.tad States. For the ten years previous to 1914, 21.6 per cent of the world's spelter was produced in Belgium. Of this production approximately 40 per cent was exported. A large percentage of the balance was rolled and of the shoots thus produced a considerable quantity was also exported.From an economic standpoint even before the war, the Belgian industry was in a unique, if not praoarious, position. Dependent upon foreign countries for ore and foreign markets for sale of products, smeltor was at a distinct disadvantage when compared with some of those of other localities. These disadvantages were partly offset by cheap coal and labor and by whatever there is of value in experience and what we may term for want of a better expression smelting tradition. However intangible this latter may be, it did have and has today an influence on commercial operations.One must not overlook the effect it will have on the revival of the industry. It may not be the determining factor but the fact that for so many years this industry flourished in Belgium, and played such an important role in the industrial life of the country will decide many operators to attempt to re-establish their operations.In 1913 the Belgian spelter plants produced 204,220 long tons of spelter or approximately 20 per cent of the world's production. During this year 500,000 to of ore were treated. The actual value of all of the products derived from treating sine ore amounted to 225 million frames."

May 1, 1919

By William O. Vanderburg

This paper describing the mining practices at the Argonaut mine, Amador County, California, is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. The mining practices described are those used in exploiting the low-grade gold ores in the heavy and swelling ground that occurs on the Mother Lode belt. The author acknowledges the assistance of E. A. Stent, vice-president, James L. Fontenrose, cost clerk, Joseph Mohorovich, mine foreman, of the Argonaut mine, and of E. D. Gardner, supervising engineer, United States Bureau of Mines, Southwest Experiment Station, Tucson, Ariz.

Jan 1, 1930

By Steve W. Webb

The Bureau of Mines is researching a new technology for dewatering clay suspensions that consists of flocculation by high-molecular-weight poly-ethylene oxide (PEO) polymer and subsequent removal of water from the floes via a trommel. The minimum amount of PEO required to dewater the clays depends on the ions adsorbed on the surface of the elay particles. Infrared studies were performed on clays with Li+, NH4+, K+, Mg2+, Ca2+, Ba2+, or 8r2+ adsorbed, with and without adsorbed PEO, to develop data to aid in understanding the dewatering mechanism. Hydroxyl stretching modes between 3,400 and 3,250 em-I, associated with water adsorbed on the clay, showed changes in intensity proportional to the ionic eharge-to-radius ratio; that is, the ionic potential. In addition. a water-bending vibration of adsorbed water at 1,630 cm-1 showed variations associated with water desorption. The data are consistent with changes in adsorption of PEO resulting from variation of the acidity of water coordinated with the exchange ions, induced by the variation in field strength of the ions with the ionic potential.

Jan 1, 1986

By K. E. Stanfield

The Bureau of Mines oil-shale program, initiated in April 1944, is concerned with the future utilization of oil shale in the United States as a source of liquid fuel. One phase of this program is the accumulation of information on the location, extent, and richness of oil-shale deposits that may be suitable for processing to oil and related products. A previous publication5/ presented, by means of logs, the oil yields of sections of the largest known oil-shale deposit in this country -the shales of the Green River formation occurring in adjoining portions of the states of Colorado, Utah, and Wyoming. This present supplementary report presents the oil yields of cores from 48 holes drilled during 1952 to 1954 in the Green River formation of Colorado, which is distributed over an area of more than 1,000 square miles. The oil yields of the 48 oil-shale sections, involving the assay of 9,651 samples, representing 22,451 feet of core, are presented by means of logs. In addition, the oil yields of samples comprising the maximum sections of 15 gallon-per-ton shale are tabulated for these cores and for the 28 cores from Colorado which were logged in the previous report.

Jan 1, 1957

By J. D. Hadden

The Bureau of Mines conducted drilling studies in the Pocahontas No. 3, the Pittsburgh, and a western coalbed to establish the gas migration characteristics for each. Gas pressures in the Pittsburgh coalbed were about 260 lb/in2 and in excess of 550 lb/in2 in the Pocahontas No. 3. Caving in drill holes prevented pressure measurements in the western coalbed. The Pittsburgh coalbed contained intersecting "clay veins" which formed gas pressure cells. Although these geological features hamper mining, they can be used to control the flow of methane into a mine working. Methane control techniques are proposed for the Pittsburgh and Pocahontas No. 3 coalbeds.

Jan 1, 1969

By James J. Olson

The Bureau of Mines recorded peak particle-velocity levels and vibration frequencies to determine the nature and intensity of ground vibrations for tunnel blast rounds at the NORAD Complex, Colorado Springs, Colo. Previous Bureau of Mines studies in quarries and underground mines had shown that scaling (dividing) the distance from the blast by the square root of the charge weight removed the effect of the various charge weights on vibration amplitudes. The analysis of variance tests performed on the NORAD vibration data, however, indicated that the cube rather than square root scaling exponent grouped the data more effectively. The empirical propagation equation, V = 560 (D/w1/3)-2.04, where V is the maximum peak particle velocity in inches per second, D is the distance from the blast in feet, and W is the zero-delay charge weight in pounds described the attenuation, with distance, of the particle velocities from the tunnel blasts in the Pikes Peak Granite of the NORAD Complex.

Jan 1, 1972

By Ralph H. Espach

The value of careful fractionation in the manufacture of petroleum products is recognized more and more by petroleum refiners. Recent studies have shown that the quality of the products depends largely on the type of fractionating equipment and on the care used in operating the equipment. For example Rue3 has shown that careful fractionation of pressure distillate will greatly reduce the amount of chemical treatment necessary to produce finished gasoline. The advantages of the combination of pipe still and bubble tower in obtaining good fractionation are well recognized in the petroleum industry. However, the equipment designed in the past has in general been much too large for convenient laboratory use. The present paper describes a continuous-distillation apparatus for the laboratory study of fractionation. This apparatus has given very satisfactory results in the study of different crude oils and petroleum products. A discussion of the theory and action of bubble towers has not been given, as this subject has been discussed previously by Cooke and Rue4. It is believed that the distillation curves of the products obtained from this apparatus show clearly its capabilities.

Jan 1, 1928

By John J. Sammarco

The functional safety of programmable electronic (PE) mining systems is an international issue and concern. From 1995 to 2001, 11 PE-related mining incidents in the U.S. were reported by the Mine Safety and Health Administration (MSHA); 71 PE-related mining incidents were reported in Australia. MSHA does not have regulations for formal evaluations of the functional safety of PE mining systems. Hence, the National Institute for Occupational Safety and Health (NIOSH), in partnership with MSHA and the industry, generated the NIOSH safety framework for functional safety of PE mining systems. An overview of the NIOSH framework is given; the key framework elements, the safety life cycle and safety integrity levels are detailed. The safety framework approach has impacted the national and Australian mining industries by enabling the industries to advance from an ad-hoc approach to a formalized and systematic functional safety process. In retrospect, valuable lessons were learned for addressing functional safety and for changing industry perspectives and practices. These lessons continue to benefit mining and are applicable to other industries as well.

By W. W. Adams

This bulletin covers all mines in the United States that were operated in 1936 to produce metallic ores and all mines that were operated to produce nonmetallic minerals other than coal, stone, sand, gravel, or their products. Reports from mine operators revealed a better safety record for fatal accidents in 1936 than in any other year except 1934 during the 26 years for which annual surveys of accidents in the mineral industries of the United States have been conducted by the Bureau of Mines. On the other hand, the record for nonfatal injuries, although better in 1936 than in any year prior to 1930, was not as good as it was from 1930 to 1935, inclusive.

Jan 1, 1939

By H. F. Weaver

The 19th National First-Aid and Mine Rescue Contest was held in the Civic Center, Charleston, w. Va., on October 2, 3, and 4, 1961. The meet was sponsored by the Bureau of Mines and the Joseph A. Holmes Safety Association, in cooperation with State mine inspection agencies, management and labor of the mineral extractive industries, and other groups interested in safety. The Arrangements Committee, as authorized by the General Committee, made the necessary arrangements for conducting the 1961 contest. Members of the Arrangements Committee were: George Trevorrow (chairman), Bituminous Coal Operators' Association; James B. Benson, Southern Coal Producers' Association; Charles Ferguson, United Mine Workers of America; Harry Gandy, Jr., National Coal Association; and James Westfield, Bureau of Mines.

Jan 1, 1962

By A. W. Maynard

Simple chemical spot tests for the identification of major alloying elements in aluminum-base alloys are described. The tests are suitable for use by nontechnical personnel working outside a laboratory. Tests for zinc, copper, manganese, and magnesium employ electrographic sampling methods and sample papers. Use of electrographic sampling in a test for magnesium in aluminum is made possible by using glass fiber filter paper. Differentiations between magnesium and magnesium-silicon alloys of aluminum and between aluminum-base and magnesium-base alloys are made by direct chemical solution tests. Description of a device for obtaining reliable electrographic samples is included. A sequence of testing for identification by alloy groups is given.

Jan 1, 1971

By A. B. Hooker, E. J. Coggeshall

"Dry cells are modified wet primary cells in which the electrolyte is held by absorbent material so that it does not spill aid the cell jars are sealed to prevent evaporation of the absorbed electrolyte. Most dry cells in commercial use are modifications of the Leclanche wet cell. In their usual form they have a hollow cylindrical zinc negative pole that constitutes the containing vessel. An absorbent material, either as a lining in the zinc jar or a bag, separates the zinc cylinder and a rod or flat plate of carbon placed axially inside. A mixture of crushed coke, graphite, and manganese dioxide is tamped about the carbon rod, and the whole mass is saturated with salaanoniac-zinc chloride solution.Dry cells are suitable for services that require minute currents continuously or larger, though limited, amounts of current intermittently. Though limited in this way, they have a wide use, even in underground mining. This paper details some of the applications of dry cells in mines, particularly from the standpoint of greater safety through their use.APPLICATIONSThere are four fields of application of dry cells to mining: (1) Electric shot firing; (2) auxiliary lighting; (3) signaling; and (4) testing.SHOT FIRINGFiring an electric detonator requires very little electrical energy because although the current flow may be 1 to 3 amperes the duration of flow is so small (1 to 4 milliseconds) that the energy withdrawal per shot is almost negligible. Batteries for shot firing need not be large; they may be used for firing either single or multiple shots."

May 1, 1934

By J. J. Forbes

First - aid training is an essential part of safety programs in the mining industry , but it is only a means to an end ; first -aid training will not eliminate accidents , but unquestionably it is of considerable value in any accident prevention program . Numerous features should be incorporated in any efficient , well - developed safety plan ; in addition to first -aid training safety work , to be reasonably effective , should include the establishment and maintenance of a safety organization , safety competitions between mines or sections of mines , safety- inspection committees , accident - investigation committees , safety meetings of mine officials , safety bulletins and posters , employees ' safety publications , Holmes Safety Chapters (which provide for monthly safety meetings of all employees ) , and numerous other activities looking to safe operation of mine or plant . These features are supplementary to the fundamentals of safety-- adequate and effective supervision and discipline . Years of experience , however , have demonstrated that first - aid training is a good accident -prevention auxiliary and should be made an integral part of every company's safety program . Many safety-organization plans have failed because they have been based upon the assumption that the supervisory force should be given full authority and responsibility for achieving safety and eliminating accidents and that the workers , who are most vitally concerned , are nonessential . First -aid training causes the employees to feel that they have a personal and full participation in the safety program and is now available so readily that no individual or organization has any valid excuse for not having it . Early investigations made with a view to bettering health and safety conditions among the employees in the mineral industries demonstrated the need of prompt care of injured employees because , under the difficulties inherent in the occupation , seemingly unimportant wounds , when not treated promptly, became infected and caused permanent disability and even death . Many seriously injured persons , brought out of mines and plants by fellow workers who were ignorant of the approved methods of giving first aid or of safe means of transportation

Aug 1, 1934

"For a good many years the Bureau of Mines and various state mining experi¬ment stations have endeavored to develop some method of utilizing the immense deposits of lignite in the United States. Work in relent year has indicated that the best method of this is to drive off the moisture and most of the volatile water from the lignite in some form of carbonizing apparatus leaving a residue high in fixed carbon and low in moisture and volatile matter, which by briquetting can be made into a high-grade fuel. The earlier forms of carbonizing equipment tried were complicated, costly to build and keep in repair, and could not be operated intermittently without being seriously damaged. During the year 1922, however the Bureau of Mines devised a very simple carbonizing oven which produces a uniformly well carbonized product. This oven is essentially a vertical shaft with means for supplying raw lignite at the top and discharging the carbonized limited at the lower end. Air in regulated amount is admitted to the shaft at two horizons, and a zone of combustion maintained through which the column of lignite passes. The lignite is thus carbonized by construction of its contained matter and a small proportion of its fixed carbon, leaving most of the fixed carbon in the carbonized product or ""char"". The degree of carbonization can be closely controlled by varying the volume of air supplied to the oven and the rate of travel of the charre down the shaft.The ""lignite char"" produced is a soft material resembling charcoal more than coal or coke, but somewhat harder than charcoal. A typical analysis is shown in the table headed ""Fuels,"" further on in this papers."

Feb 1, 1924

By John W. Finch

The Secretary of the Interior acting through the Bureau of Mines and the Geological Survey is authorized by the Strategic Materials (Public No. 117 - 76th Cong., Chapter 190 1st Sess.) to make investigation concerning essential minerals of which the quantities or grades obtainable from known domestic sources are inadequate. The Bureau of Mines, in carrying out its part of this program, may investigate deposits of such minerals in whatever manner may be necessary, in order to determine (1) the extent and quality of the are, (2) the most suitable method of mining and beneficiating it, and (3) the cost at which it may be produced. The essential objective in doing these things is to determine where and how supplies of minerals and metals of which domestic production is usually inadequate might be obtained in a national emergency, even though at higher cost than usual.

Jan 1, 1939

By J. L. Hoffman, F. W. Wood, R. A. Beall, W. E. Anable

For melting and purifying reactive and refractory metals , two electronbeam furnaces have been constructed and operated on the principle of highpowered vacuum diodes . It was necessary to design the vacuum and electrical systems , mechanical features , and operating procedures to cope with dynamic conditions . Vacuums of 10-5 torr , tens of kilowatts of power at 5 to 10 kilovolts , and the evolution of impurities at thousands of liters per minute constitute a challenging combination . The furnaces have been used to melt either button specimens weighing several hundred grams or , by feeding material as a consumable electrode , small ingots weighing several kilograms . Hafnium is among the metals that can be purified . For example , hafnium starting material with Rhn 94B was softened to Rhn 70B after 2 hours of melting under a 25 - kw electron beam , and impurity levels were reduced as follows : Oxygen , from 700 to 350 ppm ; nitrogen , from 71 to 20 ppm ; hydrogen , from 6 to 1 ppm ; aluminum from 75 to < 20 ppm ; chromium , from 80 to < 10 ppm ; iron , from 100 to 40 ppm ; and silicon , from 40 to < 20 ppm .

Jan 1, 1963

By E. P. Ferrero

Analyses of 38 crude oil samples from 25 fields in Algeria, Libya, and Nigeria are presented in this report. The 38 crude oils are listed alphabetically by country and field. Also shown are the geographic and geologic sources of the samples analyzed, the companies that supplied the samples, the general characteristics and analytical and computed data, and the production for the fields from which the samples were obtained.

Jan 1, 1966

By E. P. Ferrero

Analyses of 38 crude oil samples from 25 fields in Algeria, Libya, and Nigeria are presented in this report. The 38 crude oils are listed alphabetically by country and field. Also shown are the geographic and geologic sources of the samples analyzed, the companies that supplied the samples, the general characteristics and analytical and computed data, and the production for the fields from which the samples were obtained.

Jan 1, 1966

By R. A. Friedel, J. L. Shultz, A. G. Sharkey

The purpose of this investigation was to study the primary materials associated with the coal structure . Mass spectrometric techniques can be useful in studying the chemical structure of coal and various high- molecularweight materials derived from coal . Investigations of pyrolysis products and extracts of coal , and also whole coal , showed : 1. Aromatic hydrocarbons obtained by the vacuum pyrolysis of coal below 300 ° C possibly were sorbed material rather than decomposition products . 2 . 2 . Thirteen structural types having molecular weights from 78 to 400 were identified in pyridine extracts constituting one - quarter or more of the coal by weight . 3. Material extracted at room temperature with a methanol - benzene solvent and a vacuum pyrolysis condensate obtained at 450 ° C contain similar components . The extract and the condensate have approximately the same average molecular weights ( 200-300 ) . 4. Material extracted from coal at room temperature is altered even by mild thermal treatment . 5. Changes in various alkyl series occurring in thermally treated coal extracts can be followed quantitatively . 6. Similarities in the spectra of coal and graphite were indicated in an investigation using a mass spectrometer equipped with a spark source . Determinations on a coal - ash sample by this technique showed good agreement with data obtained by emission spectroscopy .

Jan 1, 1963