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By Marline J. Veesaert

Urban quarries offer one of the greatest opportunities for profit in non-metallic mining with limited financial risk IF properly evaluated, planned and developed to meet market needs. Location, with respect to market, is the prime consideration. Geologic considerations and quality of rock are nearly as important. Cost factors and return on investment (ROI) are the principal financial considerations. Risk of capital is determined by weighing all factors that should be considered and how well judgements are based on information acquired. It is a simple, true axiom of business that an investment must be founded on amount of capital required with its expected return plus profit, expertise required to operate and time involved. Urban quarries generally offer excellent stone product market opportunities. Costs of land with mineral containment and processing operations are much greater than in rural areas. Environmental problems have become increasingly severe. Competition from other quarries in the market area is usually directly proportional to the profit attractiveness. Risk of capital (initial, developmental and operational) can be evaluated and reduced only by thorough analysis of the entire situation. Time and money expended on planning and preliminary investigations probably represent the most productive investment of available company resources.

Jan 1, 1977

By Brian J. Gorva

The key objective of forming a cartel is to increase profits to members of the cartel by taking the following action: a) control output; and b) control price. However, while attempting to obtain monopoly profits the cartel members have to contend with costs associated with cartelization and such costs include the following: political costs; the cost of coordinating output and price; organizational costs (such as cheating); and administrative costs (such as the cost of attending cartel meetings). The objective of commodity exchanges is to provide an open, free market where buyers and sellers may openly complete transactions and pricing information can be immediately disseminated. These transactions include the following: a) to provide facilities for "hedging", or transferring price risk from buyers and sellers of physical commodities to "speculators" through the medium of buying and selling futures contracts, and b) taking physical delivery of metal on due dates.

Jan 1, 1983

By James C. Cobb

Middle Pennsylvanian (Desmoinesian) coals of certain areas of the Illinois and Forest City Basins contain epigenetic sphalerite and associated minerals in veins, clastic dikes, cleat, and other small-scale structural features. The presence of sphalerite in these coals records information about the geology of coals and coal basins, and represents a potential source for zinc as a byproduct of coal production. Origin of Sphalerite in Coal The origin of sphalerite in coal suggested by Cobb (1) involves sphalerite precipitation from zinc-bearing ?Na-Ca-Cl brines upon contact with sources of sulfur in the coal bed, e.g., pyrite, H2S, and organic sulfur. These brines were essentially at the temperature of the host coals as determined by fluid-inclusion thermometry and vitrinite-reflectance studies. The migration of these brines into coal beds may have been caused by compaction of sediments due to continued sediment loading of the coal basins. Zones of high permeability such as sandstones and the coals themselves presumably acted as conduits for the movement of the brines. The open spaces where sphalerite was deposited resulted from minor deformation associated with differential compaction and cleat formation enhanced by volume shrinkage during coalification.

Jan 1, 1982

By Bo R. Arvidson

High-energy product permanent-magnet materials of rare-earth cobalt alloys are being used in applications where space or weight are at a premium cost. New applications like friction-free bearings are also made possible. However, such magnet materials have not been commercially used in magnetic separators until now due to the high cost for the overall magnetic flux generation relative to commonly used ceramic magnets or AlNiCo magnets. The design of the new high-intensity permanent- magnet roll separator (PERMROLL) takes advantage of the unique properties of rare-earth cobalt magnets rather than just substituting for conventional magnet materials now in use for magnetic separators. Hence, the new generation of high-intensity magnetic-roll separators has some unusual characteristics that make known magnetic separation applications more economically attractive, and even expands the magnetic separation technology area to include applications for which no other feasible methods are presently known.

Jan 1, 1983

By Kenneth P. Neumann

The development of the Cyprus Thompson Creek Molybdenum Deposit near Challis, Idaho, began in 1967 when the first mining claims were staked on the intrusive rock outcrop. Exploration drilling continued for the next 14 years. During 1978, a decision was made to develop the deposit. In December, 1980, approval of the Environmental Impact Statement was received and construction of facilities and waste rock removal began. By the middle of 1983, 126 M metric tons of rock had been removed and all facilities were completed. The high work ethic of Cyprus Thompson Creek employees combined with innovation has made the mine one of the most efficient in the United States today.

Jan 1, 1983

By Kiran B. Chaudhuri

The Kivcet process is technologically the most advanced of the new lead smelting processes which have been developed over the past decade construction of the first commercial scale Kivcet lead smelter which has been designed by KHD Humboldt Wedag for Sociedad Complejo Metalurgico de Karachipampa is at present nearing completion in Bolivia. Some of the measures taken to minimise emission of harmful elements as well as methods employed to minimise energy consumption in the design of the smelter, are presented. Results of recent testwork which have added to the flexibility of the process are summarised.

Jan 1, 1982

By Enrique Levy

The publication from which this paper was abstracted is the first at-tempt to correlate all the metallogenic deta compiled by the author for the preparation of the 1:2,000,000 Metallogenic Map of Central America. It is not a treaty of metallogenic theories but rather a careful effort to postulate metallogenic provinces and epochs with the intention to stimulate other geologists and mining companies familiar with the area to criticize and improve on the ideas proposed. The sole purpose being to find new mineral deposits for the betterment of our people.

Jan 1, 1971

By Raymond L. Zahradnik

Marco Polo reported that the Chinese used "black rocks" for fuel, and recent studies indicate that the Chinese may have used coal in small amounts for two or three millennia previously. The use of coal as a major source of energy however, did not begin until about the twelfth century, when the inhabitants of the northeast coast of England discovered that certain black rocks found along the seashore--and thereafter known as "sea soles" would burn. Since this initial discovery, coal has been mined continuously, first in England and shortly thereafter in present Belgium, France, and Western Germany, and finally in all coal-bearing areas of the world, in ever increasing amounts. The production of coal in the United States began about 1820, when 14 tons were reportedly mined. Since that time the production of coal increased steadily until about 1907, after which the rate has fluctuated between the extremes of about 400 and 700 million tons per year. Bituminous coal and lignite production was 590 million tons in 1974. Value of production was $8. 9 billion. Anthracite production was b.3 million tons with a value of $157.5 million.

Jan 1, 1975

By Harvey P. Knudsen

This paper describes the results of a comparative study of the geostatistical ore reserve estimation method over three conventional methods; the polygon method, the inverse of the distance squared (IDS) method, and ELIP which is similar to IDS. Each method was evaluated on its ability to accurately predict individual block grades for one bench of the Pima Nine, located near Tucson, Arizona. Results at the Pima Mine indicate that the geostatistical method is no better nor worse in predicting block grades and total tonnage than the ELIP or IDS methods in contrast, the polygon method is clearly inferior. All of the methods would have given better results if geology had been included in the block model. At already producing mines ELlP or IDS may be good choices since they involve substantially less cost in computer time. For prospective or new properties, the geostatistical model is more attractive, due to its ability to construct confidence limits on the estimates.

Jan 1, 1976

By B. Petkof

Olivine has been an accepted industrial mineral for the last 50 years. Its initial acceptance was based on the recognition of its refractory properties by European research workers in the middle to late 1920's. Initial U.S. olivine production began in the early 1930's in North Carolina and continues there today. Olivine also is produced in the State of Washington and in other countries.

Jan 1, 1982

By Wayne S. Cavender

The geochemical association of arsenic and gold in epithermal precious metal deposits of the Basin and Range province is well documented, and in this paper I wish to discuss the evaluation and utilization of this element association for geochemical gold exploration. In 1961-62, I conducted an exploration program on lands controlled by Getchell Mine, Inc, and centered about the Getchell gold mine itself, Besides exploring for new gold deposits, the program was to evaluate these lands for potential deposits of any type; thus, a multi-phase program encompassing a number of exploration methods was conducted. I shall not elaborate on the process of designing the program or of integrating the various methods, but for gold exploration, geochemical methods were determined to have the best potential. This paper is based on that effort. Figure 1 shows the exploration area, which covers the northern half of the Osgood Mountains in eastern Humboldt County, Nevada. The Getchell $line is on the east flank of the range and is about 40 miles northeast of Winnemucca.

Jan 1, 1964

By Barry R. Doyle, Emma C. Ross

This paper presents a 20-year global account of tunneling in gassy ground demonstrating high probability of schedule delays, cost overruns, worker injuries and fatalities. Causes of these failures are systemic. Gas is seldom characterized in terms relevant to design of effective ventilation systems. Control measures deployed in tunnels are often based on outdated industrial safety codes. A change in approach is needed. This paper describes how to perform a desk study to determine if field investigation for gas is warranted, and lists the content of an effective characterization of gas in a geotechnical report.

Dec 1, 2022

By John V. Beall

The Mining Engineering Handbook is written primarily for persons interested in the economic extraction of minerals. Not everyone referring to this book will be knowledgeable about mining and, therefore, this section is intended to explain to interested persons the scope of mining as well as fulfilling the title of "Mining's Place and Contribution" among the industries of society. 1.1-MINERALS, ROCKS AND ORE In the year 1971, the number of known elements amounted to 104. Fifteen of these have been made only in the laboratory, others may have persisted from the primitive atmosphere, but, by and large, elements originated from magmas or igneous rocks of the outer rocky shell of the earth. Only eight elements constitute 98% by weight of the earth's crust. These are oxygen, 47%; silicon. 28%; aluminum, 8%; iron, 5%; and sodium, magnesium, potassium and calcium, less than 4% each. These common elements and the other less common ones are the building blocks of minerals, of which there are over 2,000 varieties. According to Webster: "A mineral is an inorganic substance occul.ring natura!ly in the earth and having a consistent and distinctive set of physical properties and a composition that can be expressed by a chemical formula. The term is sometimes applied to organic substances, such as coal." Thus, minerals are precise combinations of elements. Rocks, as distinct from minerals, are composed of assemblages of minerals. When minerals are found in sufficient concentration to warrant extraction by mining, the mineralized area is considered an ore deposit. The definition of ore is mineral that can be extracted from the ground at a profit. The economic connotation is implicit in the word ore. Since most of the useful elements compose such a small percentage of the earth's crust, the occurrence of ore deposits as we know them would not have transpired had not geologic processes concentrated the elements (see Sec. 4). 1.2-DEFINITIONS OF MINING TERMS Extensive coverage of the many descriptive terms used in mining may be found in a good mining glossary, such as is available from the Superintendent of Documents (see Sec. 35), but for convenience a number of the more common definitions are given here. Mining may be defined, as by A. B. Cummins, as the act, process or work of extracting minerals or coal from their natural environment and transporting them to the point of processing or use. Mining techniques are applied to extracting metallic minerals, such as ores of gold, copper, lead or zinc; to fuels, such as coal, anthracite, lignite and tar sands; and to nonmetallic minerals, such as lime-

Jan 1, 1973

By Zhiyuan Shen, Dan Zhao

The abstract discusses the importance of reliable mine monitoring systems for preventing accidents. It focuses on diagnosing ventilation system failures caused by roadway faults that alter airflow resistance. The paper proposes using an improved Support Vector Machine (SVM) method to identify the fault location based on changes in air volume detected by wind speed sensors. The approach involves building a sensitivity 0-1 matrix and establishing a roadway fault scope library. The improved SVM method is tested on the Daming coal mine, demonstrating its effectiveness in diagnosing fault locations, reducing training time, and improving accuracy compared to traditional SVM.

Apr 5, 2022

By J. H. Rowland, R. A. Thomas, III, C. D. Litton

Atmospheric monitoring systems (AMS) are required when using air from conveyor belt entries to ventilate working sections in U.S. underground coal mines. AMS technology has the potential to increase fire safety mine-wide, but research is needed to determine the detection and response times for fires of a variety of combustible materials. To evaluate the potential of an AMS for fire detection in other areas of a coal mine, a series of full-scale fire experiments were conducted to determine detection and response times from fires of different combustible materials that are found in U.S. underground coal mines, including high- and low-volatility coals, conveyor belts, brattice materials, different types of wood, diesel fuel, and a foam sealant. These experiments were conducted in the Safety Research Coal Mine (SRCM) of the U.S. National Institute for Occupational Safety and Health (NIOSH) located in Pittsburgh, PA, using a commercially available AMS that is typical of current technology. The results showed that through proper selection of sensors and their locations, a mine-wide AMS can provide sufficient early fire warning times and improve the health and safety of miners.

Jan 1, 2016

By William T. Ingram

Early in the 60's the author served as Chairman of the Engineering Foundation's Coordinating Committee on Air Pollution Research. One of our objectives was the development of a study on the measurement of stack emissions. Three publications of the Foundation resulted from these efforts to focus attention on the stack sampling problem.1,2,3 Two of these were annotated bibliographies covering 197 references. The third reported the results of a workshop meeting at which some 21 individuals from research institutes, industry and government discussed the possible and probable areas of research that would add to or increase the ease, precision and utility of sampling gaseous and particulate matter emitted from stacks. The American Society of Mechanical Engineers has had in its Power Test Codes a Standard Code for Determining the Dust Concentration in a Gas stream4 since 1941, The American Industrial Hygiene Association has published, in its Air Pollution Manual,5 a Section on Stack Sampling. Industry and regulatory agency requirements for stack sampling have utilized some modification of the alternatives in methodology. There has been ho single guide to stack sampling that met the needs of those who have the need to know.

Jan 1, 1970

By D. W. McGlashan

Zeta potential changes were determined as a function of pH, metal ion, and surfactant concentrations. Prom the analysis of data, flotation experiments were carried out to correlate float-ability with the differences in zeta potential. Cassiterite in water bears a negative zeta potential, The zeta potential of cassiterite is sensitive to pH changes; the electric double layer arises from the preferential adsorption of H+ and OH- ions and subsequent ionization of the hydroxylated surface. It is suspected that hydronium-ion concentration may cause reversal in the sign of the zeta potential. The ZPC was found to occur at pH 3.4. Metallic ions and the hydrated ions thereof affect the zeta potential of cassiterite in differing degrees of intensity. Without prior activation, sulfonated surfactants do not change the zeta potential of cassiterite. Sodium alkyl aryl sulfonate is especially active on lead-activated cassiterite and ferric-activated cassiteriten Microcalorimetric fiests confimed the activity of ions on cassiterite and showed the hydrated character of cassiterite smfaces. Close correlation between zeta potential and microflotation results was achieved.

Jan 1, 1969

By J. A. Pigott

Undercut-and-fill mining is a method developed by the International Nickel Company to deal with abnormal pillar mining conditions at one of its mines. Results have been such that its use has been extended to normal, pillar recovery operations in other mines of the Company as a replacement for conventional square-set pillar mining. It is anticipated that the method will also largely replace square-set stoping at INCo mines, especially for mining at deep horizons.

Jan 1, 1962

By R. B. McCammon

Four areas have been identified as favorable drill-site locations for determining whether or not a suspected prophyry copper deposit exists in Rowe Canyon, Nevada. Favorability is based on the similarity to a deposit model constructed from geochemical data for the porphyry copper deposit near Ely. Favorability is defined as the coincident number of positive anomalies for the elements zinc, silver, arsenic, antimony and iron. The favorable areas coincide with an observed magnetic high and areas in proximity to major faults.

Jan 1, 1979

By Terrence J. Stobbe

On the job injuries to the musculoskeletal system are probably the oldest of the industrial safety problems. Long before we had pinchpoints to guard, chemical vapors to ventilate, and noise to enclose, people were getting strains, sprains, and sore backs from their work activities. In spite of the age of the problem, it remains a long way from being solved. The past ten years have seen a significant commitment by the sci¬entific community to understanding the problem. Engineers, scientists, doctors, and epidemi¬ologists have been involved, and as a result, today we have a much better understanding of the problem. The first step in understanding a problem such as this is to explore its history and epidemiology. The research done by Chaffin (1977), Snook (1970), Ayoub (1978), the ILO (1962), and others, led NIOSH to publish its Work Practices Guide for Manual Lifting in 1981. The guide was based on research carried out in general industry, but subsequent research by Stobbe (1983) and Peters (1983) has suggested that the nature of the problems producing injuries in underground mining is the same as in general industry. The problems are more intense in the mining environment.

Jan 1, 1984