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U.S. demand for building and construction materials, such as construction aggregate, gypsum, and cement, remained strong in 1989. Cement imports declined slightly, representing about 17% of apparent consumption compared with 19% in 1988. Mexico, supplying 29% of the total, was the primary source of imports, followed by Canada with 21 %, Japan with 14%, and Spain and Greece with 10% each. Mexico was also the target of an antidumping petition, filed by producers in Arizona, Florida, New Mexico, and Texas, alleging that Mexican cement was being sold in these areas at less than fair value. This was the second petition filed against Mexico in the last 3 years. The International Trade Commission made a preliminary determination that the cement industry in these regions was materially injured by Mexican imports. U.S. demand improved for construction aggregate for the fourth consecutive year and was at a near-record level. The U.S. gypsum industry performed well, even though new housing starts decreased for the third consecutive year. Increased U.S. exports of gypsum wallboard and strength in the remodeling markets offset the impact of declining housing starts.

Jan 1, 1990

By William J. McDonough

Advanced materials are polymers, metals, and ceramics fabricated as intermaterial compounds, alloys, or composites. The resultant components have higher strength-to-density ratios, greater hardness and wear resistance, and one or more superior thermal, electrical, or optical properties when compared with traditional materials. Advanced materials, the basis for many of today's emerging technologies, offer savings in total energy consumption, improved performance at reasonable cost, and less dependence on imports of strategic and critical mineral resources.

Jan 1, 1992

By Gordon T. Austin

The combined production value of natural abrasives, which consist of tripoli, special silica stone, garnet, staurolite, and emery, increased in 1987. The increase was, in certain cases, because the materials were used in nonabrasive applications, such as the increased use of tripoli as a filler and special silica stone material as a special-purpose crushed stone. The increased use of garnet as a blasting media accounts for most of its growth. Production and sales of garnet were at a record-high level in 1987. [ ]

Jan 1, 1989

By Gordon T. Austin

The combined value of production of natural abrasives, which include tripoli, special silica stone, garnet, staurolite, and emery, increased about 4% in 1990. The increase in the value of tripoli production was the result of an increase in the unit value. Emery increased owing to an in? crease in the volume of the material produced and an increase in the unit value. Special silica stone experienced a decrease in unit value and an increase in the quantity produced. Garnet showed a 10% in? crease in quantity and a 73% increase in unit value. Staurolite decreased about 8% in the quantity produced, and the value of production decreased about 10%. The fused aluminum oxide industry showed a 5% decline in the quantity produced and in the value of production. The silicon carbide industry saw a 10% decrease in the quantity produced and a 9% decrease in the value of production. Production for both industries decreased 7% in quantity and value compared with those of 1989.

Jan 1, 1993

It is probably safe to say that, as the economic well-being of the mining industry goes, so goes the fortunes of mineral explorationists. And in 1977 the industry was not well at all. The year-long depression of the copper industry, marked by layoffs, temporary shutdowns, and mine closures, provided an appropriate background for the collapse of the nickel market, passage of a surface mining law that will affect the hard-rock industry in ways that are yet unclear, and the threat of operating under a new set of rules brought on by reform of the Mining Law of 1872.

Jan 5, 1978

By Roberto Antoniolli

"IntroductionSINCE ancient times, the precious metals have played an important role in influencing the course of history. Silver and gold happened to occur, although in small amounts, in those countries where the early civilizations developed. Their persistent brightness certainly amazed the primitive people, who also found it easy to shape them into ornaments •and implements. Ever since then their properties have made them seem desirable possessions.Use of precious metals as money was the natural consequence of man's desire for them. The possibility of changing an ornament into a tool or food at any time, and the ease with which such medium of exchange could be carried and hidden, further increased the demand for the two metals.Silver was probably discovered after gold and copper, and was undoubtedly found by prehistoric man as native silver. The oldest silver articles have been discovered in Chaldean tombs and date back to 5000 B.C. The earliest ascertained producers of silver were Asia Minor and the Iberian Peninsula. The Romans worked deposits in Spain, Britain, and France. In the Middle Ages, some silver was extracted from German deposits, and near the end of the Middle Ages systematic workings were carried on at Freiberg, Schneeberg, and Joachimsthal (1).Before the discovery of the New Continent, the Aztecs and Toltecs in Mexico, and the Incas in Peru, had made extensive use of silver. In the 16th century the Mexican deposits became the largest source of the world silver."

Jan 1, 1954

According to reports in August, Botswana RST's copper- nickel-cobalt smelter at Selebi-Pikwe produced 7 percent above the rated capacity of about 3,500 metric tons of matte per month. This record production occurred after 2 years of plant production difficulties and was brought about by a new management team. A shutdown for furnace maintenance had been planned for this year, but was postponed because of the improvements in production and operations. However, the mining operation continued to face problems relating to higher costs and some outstanding claims. COPPER: Effective December 1, ASARCO, Inc. and Phelps Dodge Corp. reduced their domestic copper prices by 54 per pound. Within a period of 3 days, a11 other producers (Kennecott Copper Corp., Newmont Mining Corp., Cities Service Co. , Copper Range Co. , Duval Corp., and Inspiration Consolidated Copper Go. ) had either lowered or discounted their market postings by 5¢ to 65.625¢ per pound on electrolytic wirebar and 65$ on cathode plate. Between November 29 and December 3, New York merchants decreased wirebar quotations by 1.8¢-2¢ to within a range of 57.8¢-58¢ per pound. New York Commodity Exchange (COMEX) spot-contracted copper in the week was priced at 57. 1¢ on Monday, 56.7¢ on Wednesday and Thursday, and 57.4¢ on Friday, resulting in a 5-day average of 56.9¢, London Metal Exchange (LME) cash (prompt) wirebar averaged 56.3¢ last week, opening Monday at 56.6¢, falling from Tuesday?s high of 57.2¢ to Wednesday?s low of 55.6¢ and closing Friday at 56.1¢. Foreign producers, guided by LME market transactions, lowered wirebar quotes to 56¢ per pound. Copper stocks as of December 3 totaled 187,702 short tons at COMEX warehouses and 654,573 tons at LME depositories, compared to 97,413 and 537,481 tons, respectively, for the corresponding 1975 period.

Jan 1, 1976

By D. T. Randall

The burning of coal without smoke is a problem that concerns the Government directly because of the advantages of smokeless combustion both in public buildings and on naval vessels. In addition, smoke abatement is a factor in conserving the fuel resources of the United States. Hence, as part of its general investigation of the best methods of utilizing the coals of this country, the Bureau of Mines, which is in charge of the fuel-testing work formerly carried on by the United States Geological Survey, has made extended tests to determine the conditions necessary for the smokeless combustion of bituminous coal in boiler furnaces. Bulletin 39,¢ a preliminary report, treats the smoke problem from a theoretical point of view, detailing the steps that are being taken by municipalities, manufacturers, and citizens to abate smoke, also showing the possibility of a clean city. The present bulletin not only shows that bituminous coals high in volatile matter can be burned without smoke, but also that large plants carrying loads that fluctuate widely, where boilers over banked fires must be put into service quickly and fires forced to the capacity of their units, can be operated without producing smoke that is objectionable. Proper equipment, efficient labor, and intelligent supervision are the necessary factors.

Jan 1, 1918

By E. D. Gardner

This paper is the second of a series of three on placer mining in the western United States. The first paper4 discusses the history of placer mining in the Western States and the production of placer gold, geology of placer deposits, location of placer claims on public lands, sampling and estimation of gold placers, and classification of placer-mining methods, together with hand-shoveling and ground-sluicing. This paper deals with hydraulicking, sluice boxes and riffles, recovery of gold and platinum from placer concentrates, treatment of amalgam, and marketing of placer gold. The discussion of sluice boxes and subsequent subjects in this paper applies to all forms of placer mining. The third paper deals with dredging and other forms of mechanical handling of placer gravels, and drift mining.

Jan 1, 1934

By AIME AIME

COMMITTEES. CANAL ZONE.-Col. George W. Goethals, U. S. A., Chairman; Lt.-Col. H. F. Hodges, U. S. A. ; Lt.: Col. D. D. Gaillard, U. S. A. ; Lt.-Col. William L. Sibert, IT. S. A. ; H. H. Rousseau, U. S. N.; Col. W. C. Gorgas, U. S. A.; Maurice H. Thatcher ; Joseph Bucklin Bishop ; Lt.-Col. Charles F. Mason, U. S. A.; S. B. Williamson ; Major Eugene T. Wilson, U. S. A. ; Edward Schildhauer ; Henry Goldmark ; Edward C. Sherman ; W. G. Comber ; W. B. Corse ; J. A. Walker; Joseph A. Le Prince; J. A. Smith ; Lt. Frederick Mears, U. S. A. HAVANA.-V. T. Polledo, Chairman; Diego Lombillo Clark, Jose Primelles, J. R. Villalon, Jose Artola, J. Ducassi, Luis Morales, Enrique Montonlieu. ENTERTAINMENT ON SHIPBOARD.-William L. Saunders, Chairman; Mr. and Mrs. S. D. Warriner, Mr. and Mrs. Thomas Robins, Mr. and Mrs. George.D. Barron, Mr. and Mrs. R. B. Watson, W. E. Greene. GENERAL MANAGEMENT. .Joseph Struthers, Chairman; Albert E. Vaughan. There were ten sessions of the Institute held for the presentation and discussion of, technical or professional papers. Eight of these sessions were held on the steamer while en route, and two in the ball-room of the Hotel Tivoli, at Ancon, C. Z. Mr. David W- Brunton, President of the Council, presided at all the sessions, except the sixth, at which Mr. Charles Kirchhoff, past President, occupied the chair. The following list includes the papers presented in oral abstract by the authors: First Session., October 24. The Summit Hill Mine-Fire, by W. A. Lathrop, Philadelphia, Pa. Mine-Fire at the Calumet and Hecla Mine, No. 8 Shaft., by S. D. Warriner, Wilkes-Barre, Pa. Fire in the Big Lick Stope, Lykens Valley and Williamstown Colliery, by R. V. Norris, Wilkes-Barre, Pa. Mine-Fire in the Hecksherville Valley, Schuylkill Field, Pa., by W. J. Richards, Pottsville, Pa.. Fire in the Monarch Mine, near Rock Springs, Wyo., by S. A. Taylor, Pittsburg, Pa.

Dec 1, 1910

In 1970, the U. S. Bureau of Mines contracted with Theodore Barry and Associates, a management consulting firm, to perform a one-year industrial engineering study of working-face hazards in underground bituminous coal mines. The field data was accumulated from industrial engineering observations in fifty underground mines. Supporting data for the analysis was derived primarily from the Bureau's fatal accident reports for the years 1966 through 1970. This report, Industrial Engineering Study of Hazards Associated with Underground Coal Mine Production, consists of three main parts: 1) The Fatal Accident Reports Analysis, 2) The Industrial Engineering Analysis, and 3) Multiflow Process Charts and Standard Time Data. The Fatal Accident Reports Analysis (Volume I, Section II) is based upon individual USBM fatal accident reports for 1966-1970. These were read, coded and computerized in terms of 84 significant variables. Cross-tabulations of these variables have been used to identify major underground hazards and to quantify significant causal factors. A very strong relationship was found to exist between fatal accident occurrences and low task experience. This led to a recommendation for formalized training, certification and supervision programs for miners. Victim compliance with federal regulations, mine regulations and supervisor instructions was analyzed, indicating that supervisors provide the most crucial communication link to workers. Thus, every attempt should be made to ensure the competence of immediate supervisors in the industry. Analysis of roof fall variables revealed a fatal propensity on the part of the miners to work under unsupported roof or under support conditions that are marginal. The technical approach to the problem is to make it physically impossible for a miner to work under these conditions; the behavioral approach is to ensure adequate training and develop proper safety attitudes among the miners. The Fatal Accident Reports Analysis revealed a need for normalizing data to interpret the results more accurately.

Jan 1, 1971

By Gordon T. Austin

The combined value of production of natural abrasives, which include tripoli, special silica stone, garnet, staurolite, and emery, increased in 1993. The increase in the value of tripoli production was the result of an increase in total production. Special silica stone experienced an increase in unit value but decrease in the quantity produced. Garnet showed a 19 % decrease in quantity and an 8 % decrease in value. Staurolite increased about 51 % in the quantity produced and 136 % in value compared with those of 1992. Staurolite's significant increase in value of production resulted from a 56 % increase in the unit value. The fused aluminum oxide industry showed an 8 % decrease in the quantity produced and a 13 % decrease in the value of production. The silicon carbide industry saw an 11 % decrease in the quantity produced and an 8 % decrease in the value of production. Combined, the industries decreased 9 % in quantity and 11 % in value compared with those of 1992.

Jan 1, 1993

By Matheus Teixeira Fraga

É comum o uso de modelos matemáticos no intuito de prever a qualidade do coque, sendo a maioria dos modelos atualmente disponíveis baseada nas propriedades dos carvões. Para este trabalho foram feitas misturas binárias e ternárias de carvões com variados teores de matéria volátil, a fim de se produzir coque em escala laboratorial. A reatividade ao CO2 em termobalança e resistência mecânica em tambores foi avaliada. Dois modelos para previsão de indicadores de qualidade do coque foram avaliados, o modelo aditivo e o modelo de interação. A partir da metodologia desenvolvida em laboratório foi possível produzir, avaliar e comparar coques feitos a partir de diferentes carvões e misturas. O modelo aditivo mostrou uma boa capacidade de prever a reatividade dos coques. No entanto, para os índices derivados dos testes de tambores os valores calculados mostram uma diferença importante em relação aos experimentais, indicando interação dos carvões no processo de carbonização. Nos resultados do modelo de interações, os valores calculados para reatividade e resistência mecânica, se comparados com os resultados do modelo aditivo, mostraram uma melhora na capacidade de previsão da qualidade do coque. O modelo de interações se apresenta como uma ferramenta interessante na seleção e mistura de carvões.

Aug 17, 2017

Law of the Sea. - The Ninth Session of the Law of the Sea Conference resumed July 28 at Geneva and will run for 5 weeks. The 160-nation Conference began in 1973. Two of the major factors to be discussed are the transfer of technology to the UN-controlled Enterprise or mining authority, and how the 36-member Council will make decisions. As the session completed its third week, delegates expressed little hope of completing a treaty text this year. There was a feeling, though, that substantive issues might be settled so that a treaty text can be completed next year. The Deep Seabed Hard Mineral Resources Act signed by the President on June 28, provides an interim regulatory procedure for ocean mining activities conducted by U.S. nationals that may be superseded by a law of the sea treaty.

Jan 1, 1980

By William W. Odell

In Europe and in certain other foreign countries studies have been made, extending over a period of years, relating to the winning of oil from oil shale. More work has been done in these countries than in the United States, for the reason that a supply of natural petroleum has not been so generally available there as here. Information has been obtained relating to present practices in these foreign lands in the development of a shale-oil industry. It is realized that in the past there has been very little inducement to invest capital in shale-oil enterprise in the United State's because the supply of petroleum has been plentiful; however, the time possibly is not far distant when the utilization of oil shale may be cons¬idered a desirable and financially sound venture, as it may be necessary before long to augment our supply of oil with that recovered by processing shale. The data presented herein portrays at least some of the thoughts of those engaged in obtaining oil from oil, shale in Europe, and they depict some of the results thus far obtained as well as certain plans for further efforts to win oil from shale; it is hoped that those who undertake the development of a shale-treating industry in this country will find useful information in this report.

Jan 1, 1946

In this issue, the Bureau of Mines announces the availability of the latest of its Mineral Perspectives series: ?MP-4, mineral Industry of Western Europe." This publication describes the mineral industries of 19 Western European countries. For readers unfamiliar with this new series, reproduced below and on the two succeeding pages, is the section dealing with the mineral industries of France. Information regarding acquisition of this publication is found inside the back cover of this issue. FRANCE France is a moderately important producer of minerals, including iron ore, coal, potash, fluorspar, and uranium. In addition, France is a significant processor of imported minerals, chiefly for its own consumption. In general, it has exportable surpluses only of a little iron ore (low-grade ore exported to Luxembourg) and some nonmetallics.

Jan 1, 1977

By Henry S. Washington

Introduction. It Still Rains On The Choco ! I Well Remember One Evening A Dozen Years Ago, While. Traveling Toward The Town Of Negua In A Small Champa Or Dug-Out Canoe, The Rain Fell So Heavily That I Had To Work My Hardest To Bail Out The Water With A Large Totuma Or Gourd In Order To Keep The Canoe Afloat, The Senegambian Meanwhile Plying His Paddle In The Stern. If Any One Thinks Bailing Is Easy Work, Let Him Scoop Out A Quart Or More At A Stroke, 40 Times A Minute For Half An Hour, And I Venture That He Will Change His Opinion. These Small Canoes Required Only One Paddler, To Make The 3 Miles An Hour Which Is The Standard Rate Of Aquatic Progress On The Choco. Another Time, On The Atrato River, About Six O'clock In The Afternoon, The Rain Fell So Heavily Than An Empty Gourd, 9 In. In Diameter And 4.5 Deep, Was Filled To The Brim In 90 Sec., Timed By A Watch. Such Downpours Are Typical, But Unless Caught In One It Is Not Specially Noticed. These Downpours Seldom Last More Than An Hour, And Frequently Cover Only A Limited Area, Occasionally Falling On One Bank Of A River And Not On The Other. During The Night-Time,' The Rain, If Gentle, Will Usually Last Until Dawn, And Sometimes An Intermittent Drizzle Will Keep Up All Day As Well, Although, As A Rule, It Rarely Rains During The Day. The Rise Of The Rivers, Due To The Rain-Fall, Varies From A Few Inches To Several Feet. One Night In August, 1899, The Spuds Of The Dredge Margaret, Operating On The Atrato River, Showed A, Rise Of 16 Ft., And For 3 Days Thereafter Occurred The Greatest Flood Known In That District For 32 Years. The Dredge Had All Three Spuds Clown, And The 2-Yd. Shovel Dragging On The Bottom. A 0.75-In. Cable Fast To A Stout Tree, 700 Ft. Away, Stretched Tight

Sep 1, 1908

By Michel C. Frippel

This section of the Minerals Yearbook reviews the minerals industries of 29 countries: the 12 nations of the European Community (Belgium, France, the Federal Republic of Germany (FRG), Italy, Greece, the Netherlands, Denmark/Greenland, Spain, Portugal, Luxembourg, the United Kingdom, and Ireland); 6 of the 7 nations of the European Free Trade Association (Sweden, Nor-way, Finland, Iceland, Austria, and Switzerland); Malta; the 8 Centrally Planned Economies of Eastern Europe (the German Democratic Republic (GDR), Poland, Yugoslavia, Albania, Hungary, Czechoslovakia, Romania, and Bulgaria); and the U.S.S.R. Western Europe Western Europe [loosely defined to include the 12 nations of the European Com-munity (EC) and the 7 nations of the European Free Trade Association (EFTA)] is the single largest trading area and consumer of raw materials in the world. If Western Europe was at one time an important mining sector, it has now increasingly relegated the role of supplying minerals for its minerals processing industry to its ex-colonies in North and South America, Africa, and Australia. In this regard, Western Europe is the most important determinant of raw materials consumption (and thus raw materials production). There is an important reason for this since Western Europe lies somewhere between Japan at one extreme and the United States and the U.S.S.R. at the other extreme as regards the availability of natural resources.

Jan 1, 1992

The contribution of minerals to the growth and development of the United States is best demonstrated by the uses which have evolved during the past two centures. During pre-Revolutionary days the colonies were essentially agricultural in character, producing cotton, tobacco, rice, indigo, grains and flour, fish, livestock, dairy products, and timber. Shipbuilding was the major manufacturing industry. In 1763, the total value of exports for Virginia, Maryland, New York, Pennsylvania, and Massachusetts was £2,722,000, of which £55,000, or 2 percent, was for "copper ore, and iron in pigs" (3)1 and £49,000 was for 21,000 barrels or hogsheads of "pot-ash." The value of 75 ships built for sale in 1763 by the colonies was £61,500.

Jan 1, 1976

1. Domestic Production and Use: In 1975.12 companies operated 31 primary aluminum reduction plants, with 3 firms accounting for 67% of production capacity. Washington, Oregon, and Montana accounted for 37% of the total production; Gulf Coast States 21%, Northern States 29%, and other Southern States 13%. Output of primary metal in 1975 was valued at $3.0 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1975, building accounted for about 21%; transportation 19%; electrical 14%; packaging 18%; and consumer durables, 9%.

Jan 1, 1976