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By J. Mackintosh Bell

External trade strongly influences the well being of all nations. In the modern economic mechanism, no country is so well endowed that it has not to import commodities from others and to export its products in turn to make good its deficiencies, to rectify or improve its financial structure. From the standpoint of international commerce, Canada is strategically well placed. On the south she is bounded by the richest country in the world. On the east she faces the Atlantic, on the west the Pacific. On both coasts there are fine harbours to which lead great lines of railway that span the continent. Canada is now fifth among the exporting nations of the world. For disposal abroad, she has enormous quantities of primary commodities and substantial amounts of manufactured goods as well. But she is far from being self-sustaining. She is unusually dependent on foreign trade, not only because of the commodities she has to sell but because of the lack of many essential articles she does not or cannot produce. To Canada, external commerce is vastly more important than internal trade. The wealth of nations is decided by their ability to produce more than they need, to sell more than they buy, and to build up favourable balances resulting from trade or services. With few countries, however, are returns perennially satisfactory. Fruitful periods are followed by leaner years. In times of prosperity foreign credits are increased, monetary systems strengthened, reserves accumulated to withstand recurring days of strain. Today, the foundations of financial systems are being re-examined, "dogmas hitherto accepted as canonical are being questioned" . It is not only in Europe and America that men search for illumination in problems arising from monetary restrictions.

Jan 1, 1933

By Warren E. Morrison

The first major evaluation of the nation's raw materials prospects after World War II was completed by the President's Materials Policy Commission (Paley Commission) in 1952 and submitted to the President in June of that year, as a five-volume study entitled Resources for Freedom. The bulk of the report was devoted to an analysis of the past, present, and probable future of the Nation's mineral supply industries. The Commission's evaluation of the future situation regarding minerals was derived from its forecasts of the probable domestic demand for the major minerals in the 1970's. This demand analysis was made in the context of probable worldwide demand. Several crucial assumptions were made by the Commission's fore-casters. It was assumed in 1950 that the next 20 to 30 years would see no major wars and be a period of sustained economic growth. Another assumption was that the anticipated demand for raw materials must be supplied at essentially no increase in real cost in order to avoid crucial supply problems. The Commission's forecasts were derived within the context of the country's expected future rate of economic activity. The gross national product (GNP) growth to 1975 was derived from projections of the number of people in the labor force, hours of work, and an index of probable production measured per unit of labor input. It was believed labor hours would decrease and labor productivity would increase. The result was a forecast GNP growth rate of 3 percent.

Jan 1, 1970

Jan 1, 1902

Real economic growth for 1988 may fall short of the 3.3% projected by the Department of Commerce in August 1988 because the summer drought and intense heat in many areas curtailed output more severely than expected. The economy grew at an average annual rate of 3.0% for the first three quarters of the year, slowing in the second and third quarters. Export growth, which occurred even as the dollar edged up compared with other industrial country currencies, was an important factor in the expansion. Notable gains were posted in sales of machinery, computers, aircraft, chemicals, and telecommunications equipment. Imports increased, but not as much as exports, and the U.S. trade position was still much improved from that of 1987. Personal consumption expenditures grew slightly faster than the economy as a whole. Purchases of consumer durables showed notable strength in the first half of 1988, but slowed down in the third quarter. Despite the moderate rise in interest rates, business spending for new plant and equipment also rose and contributed to 1988 gross national product (GNP) growth. Both new business investment and export demand spurred orders for U.S.-made machine tools. Orders for machine tools for the first 8 months of 1988 were almost triple those in the corresponding period in 1987.

Jan 1, 1989

By Paul C. Hyndman

The U.S. Bureau of Mines inventoried Federal mineral lands in Idaho and classified them in detail, section by section, according to their availability for mineral exploration and development as affected by legal restrictions and agencies' management practices. The Bureau also identified known mineral deposit areas (KMDAs) and areas conducive to oil, gas, and geothermal resources. This information is shown on maps (developed in part by geographic information system technology) that spatially compare the availability for mineral entry of Federal land with these KMDAs to demonstrate the extent and severity of restrictions on mineral entry. Idaho contains 53.1 million acres, 35.7 million (67%) of which is Federal mineral land. About 7 million acres of this land is within KMDAs that host medium-to high-value locatable mineral deposits; 36% of this land is available, 27% is slightly to moderately restricted, and 37% is severely restricted or unavailable. For the leasable minerals, about 1.8 million acres are within KMDAs that host medium-to high-value phosphate deposits, about 5.4 million acres are favorable for oil and gas resources, and 3.9 million acres for geothermal resources. The percentages of land availability are 30%, 45%, and 25% for the phosphate acreage, 38%, 34%, and 28% for the oil and gas acreage, and 43%, 30%, and 27% for the geothermal acreage.

Jan 1, 2012

By Marcello M. Veiga

Informal gold mining operations in the Amazon emit about 100 tonnes of mercury annually because of poor amalgamation practice. Lack of information and the complexity of mercury transformations hinder effective action to prevent such pollution and/or monitor its extent. In the past, mathematical equations have been formulated to deal with the correlation of natural variables and mercury in biota but often, the error range is too great to provide useful models. Projection of physico-chemical variations in an environment subjected to mercury emissions onto the extent of bioaccumulation is fraught with many uncertainties and unknowns such as internal correlations between variables and the site-specific nature of biota contamination. Often assumptions about closed systems are invalid when applied to natural environments. This work presents a heuristic approach to this problem in which amalgamation methods and natural variables are dealt with using an IF-THEN rule-based system that concludes about levels of emission and risk of bioaccumulation. The system is able to handle uncertain or vague data and yet still provide useful output. Belief in mercury oxidation or dangerous conditions are examined using Fuzzy Logic techniques and Inference Equations. These belief levels are derived from thermodynamic equilibrium data together with field observations of natural variables. This procedure can reduce the need for sophisticated analytical equipment and can provide information and diagnosis to non-technical people.

Jan 1, 1994

The mineral Industry, following the economy as a whole, experienced little growth in 1992. However, with modernized plants, efficient workforces, and lower operating costs, the industry is well positioned to take advantage of possible improvement in the national economy during 1993. In addition to the significant 1992 events highlighted below, important events, trends, and issues within individual mineral industries are addressed in the commodity sections that follow. The value of processed materials of mineral origin is estimated to have been about $310 billion in 1992. The value of U.S. raw nonfuel minerals production in 1992 is estimated at approximately $32 billion, a 3% increase over 1991. The value of domestic minerals production has increased in all but 4 of the last 32 years.

Jan 1, 1993

A major domestic aluminum producer raised its price for primary aluminum metal from 44 cents per pound to 48 cents per pound, effective August 5, 1976. Other major producers have increased their list prices by equivalent amounts COAL: The strike which began July 19 in southern West Virginia enlarged by early August to involve approximately 80,000 miners in nine States. As of August 4, the aggregated loss of production is estimated to be 5.8 million tons. Reportedly, at this time, the railroads which serve the struck areas are feeling the largest impact with coke plants and electric utilities relying on stocks which are generally high.

Jan 1, 1976

The value of processed materials of mineral origin was estimated to have exceeded $297 billion in 1991. U.S. raw non fuel minerals production in 1991 was estimated at $30.8 billion, a 5.8% decline from that in 1990. This estimate was based on data for the first quarter of 1991 (in some cases two quarters) for most of the 21 minerals that for many years have accounted for more than 95% of the industry's production value. The value of minerals production has increased in all but 4 of the last 30 years. The metals component of production value has fluctuated much more than the industrial minerals component, reflecting the greater volatility of metal prices. Employment in metal mining rose slightly in 1991, but this gain was more than offset by a decline in employment in industrial mineral mining, resulting in an overall decline of 3.0% to 164,600 workers in 1991. Prices of several major metals declined during 1991, reflecting weakness in the economy, causing some metal mines to shut down or reduce operations.

Jan 1, 1992

By Sean Gallagher

This report was written in an effort to provide better control measures for low back pain (LBP) and low back disability in the mining industry. There are numerous factors associated with development of LBP, many of which can be effectively controlled while some cannot. Better job design is promoted as the best method of reducing cases of LBP and can also reduce the disability (i.e., lost time from work) associated with LBP when it happens. The report draws attention to what is currently known about LBP, what the causes are thought to be, and discusses recent back injury trends in the mining industry. Research describing unique physical demands in mining, such as the capabilities and limitations of working in awkward postures, is also presented. Methods that can be used to prevent initial LBP episodes are provided, including facilities design and layout for materials and supplies, use of mechanical-assist devices, improved design of lifting tasks, and better seat design. Methods of reducing the disability associated with LBP (including workplace design, proactive return-to-work efforts, communication, and management commitment) are also discussed. The report concludes that control of LBP and disability in mining requires a comprehensive approach to limit the repetitive loading that can occur on the low back due to manual materials-handling tasks and exposure to whole-body vibration (WBV). Specific recommendations include the following: ? Successful LBP prevention efforts require a proactive program that has strong management commitment and incorporates employee involvement. ? More efficient supply handling systems and use of mechanical-assist devices can greatly reduce exposure to hazardous lifting tasks. ? Lifting tasks should be designed to minimize low back stress. Tools to evaluate and redesign lifting tasks are presented. ? Improved seat design can reduce exposure to WBV and improve posture, leading to reduced LBP risk. ? The disability associated with LBP can be reduced. Getting the worker back on the job as quickly as possible is in the interest of everyone involved.

Sep 1, 2008

By Daniel Harrington

For several years the United States Bureau of Mines has been making a study of ventilation in metal mines, this study covering practically all the important mining districts of the country. One of the districts where a close and extended study was made was that of Butte, Mont., with its numerous interesting problems and conditions. In February, 1916, Daniel Harrington, mining engineer of the United States Bureau of Mines, was detailed to investigate the circumstances surrounding the death of 21 men in the fire at the Pennsylvania mine at Butte, and during that investigation he made underground visits to several of the large mines through the courtesy of the mine operators, and became much interested in the ventilation conditions. In May, 1916, Mr. Harrington was detailed te work in cooperation with Dr. A. J. Lanza of the United States Public Health Service in an investigation of the prevalence and causes of miners' consumption in the district. This work broadened so much that the investigation was not completed until late in 1918, the investigators making a detailed inspection of all working places in four large mines and a more or less extended examination of conditions in about 20 other mines. Ventilation was recognized immediately as being an important factor in the health of miners, and from the outset of the investigation a large part of the work consisted in obtaining and compiling data relative to the flow of air, humidity, and temperature. The officialsof the North Butte mine were engaged in making a study of ventilation problems before the coming of the investigators, so that opportunity was given to work with those officials for several months. Detailed data on air flow, temperatures, humidities, and an analyses had been obtained before the fire in the North Butte mine June 8, 1917, which resulted in the loss of 163 lives. Much information was obtained during the progress of the fire, and a detailed examination was conducted after the fire, hence an exceptional opportunity existed to study conditions relating to ventilation. This bulletin is a result of studies made from the data collected during the two and one-half years of study and observation a-boveoutlined. Its publication has been delayed through lack of funds for printing. Other publications relative to metal mine ventilation -in other parts of the United States are expected to follow.

Jan 1, 1923

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

Domestic Production and Use: In 1976, 12 companies operated 31 primary aluminum reduction plants, with 3 firms accounting for 63% of production capacity. Washington, Oregon, and Montana accounted for 36% of the total production; Gulf Coast States 19%, Northern States 29%, and other Southern States 16%. Based on published producer prices output of primary metal in 1976 was valued at $3.8 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1976 building accounted for about 25%; packaging 22%; transportation 19%; electrical 13%; , consumer durables 8%; and other uses, 13%.

Jan 1, 1977

Jan 1, 1882

This report describes Phase I of the project --Development of a Mechanized Scaler --performed by Battelle, Pacific Northwest Laboratories for the U.S. Bureau of Mines. The objectives of Phase I were to 1) assess the needs of the industry as related to mechanized scaling; 2) conceive, evaluate and select mechanized scaler concepts; and 3) prepare preliminary designs of the selected machine concepts. To assess the scaling needs of the industry, we reviewed both U.S. and foreign literature, evaluated U.S. scaling accident statistics, reviewed existing mechanized scaling equipment, performed a series of mine visits and telephone interviews with mine operators, and assessed the applicability of a loose-rock detection system. The literature review identified over 25 scaler-related articles. However, little of the information could be used directly in the conceptualization and design portions of the project. Three articles did supply information on a number of machines used in Europe, along with statistics describing their effect on mine safety. For example, the French reported a 50% reduction in the total number of scaling-related accidents and a full 80% reduction in the number of lost-time injuries in the Lorraine mining district.

Jan 1, 1981

By H. C. Fowler

Technical developments in the American petroleum industry as regards exploration, drilling, production, and transportation were characterized by many anomalous conditions during the half decade 1914-19. A review of the literature of that period discloses the striking fact that individual geologists, engineers, and other technologists were surprisingly well versed concerning the occurrence of natural hydrocarbons and methods of extracting them and were acquainted with many of the physical and chemical characteristics that influence the behavior of fluids in natural reservoirs. However, the industry as a whole knew little of the correct application of recognized fundamentals; indeed, judged by present standards certain expediencies of self-styled "practical' operators seem cumbersome, if not evidences of ignorance.

Jan 1, 1941

By Thomas T. Read

I. INTRODUCTION. WHEN so much has been written upon a subject on which so little definite information is available as upon this, some reason must needs be assigned for adding to the volume of literature. A sufficient reason is found in the probable great future importance of China as a producer of mineral wealth. The present undeveloped state of mining in the Empire is due to many causes, among which the most important are the relatively simple needs of the population, the lack of transportation-facilities, the inelastic regulations governing the industry, and the superstitious reluctance of the people to make excavations which might disturb the spirits of the earth and air, or of ancestors. Iron is the metal most in demand, yet the needs of the population, until recently, only made necessary a production of approximately 0.5 lb. of iron per capita per year. The present annual production of iron for domestic consumption, in the United States, is nearly 600 lb. per capita. The curious state of development of transportation in this interesting country has been a greater handicap upon the mining industry than upon any other. The point upon which it hinges is the absence of a road-system. Except for a few military roads, now almost impassable, there are no roads in China; that is to say, there is no land which is set aside as a right of way, belonging to the commonwealth. Throughout the agricultural districts, generally speaking, the entire area is in private ownership, and the lines of travel are between fields. There is a constant struggle for existence between the owners of the land and the traveling public, with the natural result that the so-called roads usually

Mar 1, 1912

LOCAL COMMITTEE OF ARRANGEMENTS. Major J. W. Powell, Chairman; F. P. Dewey. Secretary; S. F. Emmons, A. S. Hewitt, J. P- Hilgard, Charles Knap, and F. W. Taylor. THE opening session was held in the hall of the new National Museum, on Tuesday evening, February 21st. President Metcalf introduced General W. T. Sherman, one of the Regents of the Smithsonian Institution, who read the following address: ADDRESS OF GENERAL SHERMAN. MR. PRESIDENT AND GENTLEMEN : I have been invited to meet you here this evening to extend to you the cordial greeting of the regents of the Smithsonian Institution, and to assure you that they are most happy to have it in their power to place at your disposal this beautiful hall, dedicated to science and art. This National Museum is the property of the United States, of which the regents of the Smithsonian are simply the custodians, and the board has delegated to its secretary, Professor Baird, the right to extend its use to the National Academy of Sciences and like kindred societies, among which we are glad to class the Institute of Mining Engineers. It is eminently fit that you should meet here at this, the nation's capital, under a roof partly your own, devoted to natural sciences, and in the shadow of the Smithsonian, founded for the exclusive purpose of collecting and diffusing knowledge among men. Of all the workers employed on earth no single class seem to me more worthy the respect of their fellows than those who seek beneath the surface for the useful minerals and metals which contribute so largely to the wealth and comfort of mankind. In no branch of human industry does intelligence come so immediately in contact with labor. To the mining engineer chemistry, mineralogy, and geology are as reading, writing, and arithmetic to the merchant;

Jan 1, 1882

By R. W. Hodder

"Archean lode gold deposits of both vein and chemical sedimentary types typically have major enrichments of certain rare elements, including Au, Ag, As, Sb, B, W, Se, Te and Bi, coupled with low or negative enrichments of the more abundant and mobile base metals, Cu, Pb and Zn. On the other hand, in massive base metal sulphide deposits Au, Ag, Cu, Zn and in some instances Pb are all enriched by a factor of 200 to 2000 t:'Jf'1pared to background and there is no large separation of gold relative to the base metals.The fluids from which gold was precipitated in veins were at temperatures of 320 to 480°C, at lithostatic pressure, had significant C02, and Na """" K; whereas the fluids which generated base metal deposits were at 250-300°C, at hydrostatic pressure, had C02 < < H20 and Na > > K.Many lode gold deposits are characterized by K, C02 and Si additions to their enveloping rocks, whereas base metal deposits typically have a fixation of Fe, Mg, Si and S in footwall rocks. Lode gold deposits may also have a relatively large halo of low-temperature oxidative, sadie spilitization in enclosing volcanic rocks, where seawater has later streamed into cooling stocks or flows that have initially acted to focus gold mineralizing fluids along thermal contraction fractures. The submarine environment is one hydrologically appropriate for the mixing of two initially independent hydrothermal systems, and the blending of their separate characteristics. Hence, lode gold and base metal massive sulphide deposits appear to be products of two distinctly different crustal and hydrological regimes. The former involves a high-temperature, high-pressure discharge of fluids which probably were generated during dehydration accompanying burial and progressive accumulation of volcanic-sedimentary sequences, with an additional influence of marine water in the near-sea-floor environment. The latter represents thermally driven convection of ocean water at lower temperatures and under hydrostatic conditions.Auriferous fluid systems with only minor base metal content could plausibly be generated during dehydration accompanying burial and metamorphism, when the water-to-rock ratio is low and halogen availability is limited by crustal abundance (- 60 ppm Cl). These two factors may constrain the uptake of the abundant base metals into fluids, but the solubility of rare elements is not constrained by limited fluid; and preferential uptake of Au along with other rare elements may be promoted if such elements compete more successfully for the limited halogens than the base metals, and/or have an alternative complexing agent such as CO or C()j-."

Jan 1, 1982

By A. R. Barnes, N. Stubina

Increasingly, gold producers are forced to treat ever more refractory ores. While ores containing pyrite, arsenopyrite and carbonaceous material have been subjected to complete pressure oxidation (PDX) as the standard process for such ores, recent improvements in fluid bed roasting technologies have led to a resurgence of interest in roasting as a viable alternative. The lower capital and operating costs of roaster installations add further impetus to this trend. The Extractive Metallurgy Group at Xstrata Process Support operates four fluid bed reactors of various sizes which have been utilised on a large number of projects to treat highly refractory ores. Preliminary mineralogical modelling of both the physical and chemical aspects of the roasting process and subsequent testing under carefully controlled conditions has allowed clients to obtain gold recoveries approaching or matching those achievable by PDX. The flexibility of the units to operate in various modes- " bubbling bed", circulating bed, two stage, sub-stoichiometric and combinations of these, and the range of sample sizes accommodated, from a few kilograms to a few tons, has enabled XPS to accommodate clients with a wide variety of gold bearing refractory ores from all over the world. This paper outlines the key challenges of fluid bed roasting of refractory gold ores, describes the methodology used to design the testwork program and provides some results from select test campaigns.

Jan 1, 2011