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By R. Bruce Tippin

The silicates represent the largest and most common group of minerals on earth. Yet in spite of the chemical similarities, numerous mineral processing plants worldwide are operating successfully to yield varied commercial products for numerous uses. The silicates that are commercially produced in the United States by flotation include quartz, feldspar, mica, spodumene, talc, kaolin, and wollastonite. The operation of several plants and the conditions affecting mineral separation by flotation are described. Because the process is usually dictated by the desired market, specifications for the most common products are provided. Potash is a basic fertilizer component, along with phosphate and nitrogen. Potash is typically produced from underground evaporite beds or recovered from natural brine solutions. Flotation of potash is unique in that it is processed in a saturated salt solution. The potash flotation process is outlined and several commercial operations are described.

Jan 1, 1999

By Jukka Pukkila, Pekka Särkkä

Intensive co-operation between mining industry and mining machine manufacturers during an eight year program Intelligent Mine™ led to a new concept for applying automation technology in mining to improve the productivity and safety of mines. 'The results of the program are now implemented in several mines in Finland and with similar ideas as well elsewhere in the world. The degree of optimal automation of an intelligent mine depends on several technical and economical factors. The basic precondition for the approach is a clear improvement in total economy of the mine.

Jan 1, 2002

By Lawrence P. Kennedy

The Lynne deposit is a volcanic-to volcaniclastic-hosted, Zn-Pb-Cu-Ag orebody located in the early Proterozoic magmatic terrain of northern Wisconsin. As of February 1991, core drilling has partially delineated a multi-million ton, near-surface, disseminated to massive sulfide deposit. The deposit is hosted by a gently dipping sequence of fragmental rhyolites, felsic tuffs, less abundant dacite to andesite flows, and fine-grained volcanic sediments. The deposit is broadly conformable With the host rock stratigraphy, but the ore zones thicken and coalesce in the central part of the deposit.

Jan 1, 1991

Unless otherwise indicated, pounds are US avoirdupois, feet are US, and gallons are US.

Jan 1, 1985

Information Technology has addressed those problems unique to senior management in the mineral industry. In general, these problems are those concerned with decision-making. Peter Drucker in his discussion of making effective decisions identifies five phases: (1) define the problem, (2) analyze the problem, (3) develop alternate solutions, (4) decide the best solution, and (5) convert the decision into effective action. The scope of the chapter by Guernsey addresses the first three phases which provide input to the decision-maker. The decisions to be made relate, in most instances, to the economics related to a mineral property or process. Computer models have been designed to generate these economic and financial evaluations. No one model is appropriate to the solution of all management's problems. In this chapter several applications are identified and summarized; a model for the economic evaluation of a mineral property is described in greater detail. The implementation of such models is dependent on the unique needs of management.

Jan 1, 1979

By Owen E. Owens

INTRODUCTION This paper deals with the main components in exploring for and developing a gold ore deposit. It addresses geology, exploration drilling, ore reserves, and evaluation criteria in an integrated manner to present an overall picture. Gold forms such a small component of a gold ore body, that particular care should be taken in dealing with the data from a developing deposit. The paper lists the main gold ore deposit types and their character. Their differences, as well as differences to other types of ore deposits, are important to understanding exploration approaches, and problems of ore reserve definition. Gold exploration has enjoyed a great boom in recent years. Many new ore deposits have been developed but experience shows that definition of gold is not a simple straight forward process and this outline attempts to point out some of the important aspects of ore reserve definition including some pitfalls. GOLD DEPOSIT TYPES The Witwatersrand deposits in South Africa produce about 50% of the world's gold. The gold occurs as fine grains in thin beds within gently dipping quartz pebble fan conglomerates usually with associated pyrite grains. It is characterized by rather uniform distribution of gold along thin layers within the conglomerate.

Jan 1, 1988

By Ernest Selig, John Dunnicliff, Delon Hampton

This paper provides a summary of a two-day conference held in New Orleans in March 1980, entitled "Tunnel Instrumentation: Benefits and Implementation." The conference addressed two major questions: First, what are the benefits of using instrumentation during tunnel construction? Second, what contractual relations should be established for conducting instrumentation programs during tunnel construction? Each session consisted of brief formal presentations and extensive panel discussions with participation from attendees. Attendees included owners, designers, contractors, and instrumentation specialists. This paper presents a consensus of views expressed during the conference.

Jan 1, 1981

By Armstrong

This is a world of change and has been from the beginning. There are constant efforts on the part of natural forces to wear down the high spots and fill in the low spots. Wind and water over eons of time tunnel through obstacles and build windways and waterways to make movement of air and water easier and more efficient. It is a natural, never ending, ever changing continuing effort. Man in his struggle to survive, and to progress, has had to adapt the terrain of the earth to fit his needs the best he could. First, he used natural caves to protect him from the elements; then he learned how to build earth and rock-moving tools from antlers, bone, rocks, and sticks and adapted his cave to increase his security and provide better protection from heat and cold and from his predatory enemies. As his numbers increased, so did the necessity of further adapting his environment to accommodate his needs. Water was usually not available when and where needed, especially in the desert areas where civilization developed, and long tunnels were drilled to intercept ground waters and lead them to underground caves carved out of soft limestone. Most of the tunnels of early man were to bring water from where it was to where man needed it. Then, as now, as man increased his chances for physical survival, he turned to the quality of life -- and this reflected in the concern for life after death. This lead to the elaborate shafts and tunnels for the protection and prservation of the more affluent noblemen and pharaohs of the early Egyptian civilization. Man used the underground for the stable temperature and for protection and safety.

Jan 1, 1974

This section is addressed to the computing needs of corporate (top) management which are less specialized than the computing needs of operating or divisional management described in the previous sections. It is essential that the computer be used as a tool to serve corporate management and that information and results are presented in a succinct form. A key responsibility of the manager of computer applications is to communicate well with corporate management. A common trap for computer management is to allow the development and implementation of sophisticated and academically interesting computer applications which do not enlighten corporate management in its decision-making task. Thus it is essential to devote sufficient time and effort to designing and specifying a computer system before developing and implementing the system.

Jan 1, 1979

By H. W. Peirce

Arizona is a sun-belt growth-region where 13 tons of industrial (nonmetallic) minerals is being produced annually per capita. In 19B5, non-fuel mineral production reached $1.532 billion and consisted of metallic ($1.277 billion-84%) and nonmetallic ($253.5 million-16%) earth materials. Sand-and-gravel value was second only to copper. over 90% of the value of nonmetallics is represented by combined sand, gravel, cement, and lime. The remaining less than 10% ($25 million) was attributed mainly to stone, specific volcanic products (cinder, perlite, pumice), gypsum, clays, salt, zeolite, and others. Current interest in industrial-mineral development in Arizona is high, especially in the geologically complex Basin and Range region.

Jan 1, 1988

By R. P. Moran, B. C. Lewis

The objective of this article is to discuss the fundamentals for determining the value of a limestone reserve or operation. The general step-by-step procedure, while prudent, is subject to the various site-specific issues that influence the valuation calculation. The most common methods for determining fair market value of mining lands are: comparable sales, operational analysis, and royalty analysis. An overview of typical eastern limestone mines (both quarries and underground) is presented. Specifically, properties in West Virginia and Alabama are reviewed and the sample methodologies and valuation calculations are presented.

Jan 1, 1991

Because of the different types of reagents used for the flotation of sulfide and nonsulfide minerals, it is convenient to consider these two groups of ores separately. The metal sulfides and native metals are substantially all floatable with xanthate and similar collectors.

Jan 4, 1982

By Herschel H. Potter

While preparing this paper, I soon realized I had a problem in defining what injuries should be classified as "personal." Admittedly, in some cases, falls of persons, sprains and strains, pulling and pushing injuries, and back injuries may have been caused by the individual. But, I believe the number of injuries directly attributed to an individual's carelessness is relatively small in comparison to the total number of injuries in those categories. For discussion purposes, the injuries most often considered to be personal, that is, caused by individuals are those classified as back injuries. My paper will be devoted to back injuries because this category represents the greatest number of injuries occurring in coal mining. A man's best friends are his wife, his back, and his dog. The back, however, has a reputation of not being as faithful as his other two friends.1 "Industrial back injury is one of the major occupational health problems plaguing industry to- day. According to national surveys, back injury accounts for more lost time than any other occupational injury and costs companies thousands of dollars in compensation, medical fees and over- time pay."2 A study conducted by USA Today found that back ailments afflict an estimated 75 million Americans, have totally disabled about 2.5 million adults, lead to as many as 200,000 required surgeries each year, are a leading cause of absenteeism and disability, are the second leading cause of hospitalization, are responsible for 18 million doctor visits a year and cost about 93 million work-days annually. The cost to industry is estimated at $14 billion a year.3 During the past 30 years, a great deal of accident prevention education has been directed toward the reduction of back injuries. However, this effort has not produced any great change in the incidence of the injury. Back injuries should be of the utmost concern to everyone here today. I don't need to tell you what the incidence rate is for back injuries, nor will I use any statistics to inform you of the incidence rate for the coal mine industry or any specific mine. It is only important to know that the number of back injuries is excessive. Back in- juries resulting from lifting have been and continue to be one of the most constant and undiminishing problems in the occupational environment. The fact is, we use our backs to per- form work that the back was not designed to do. Historically, manual materials handling related accidents have consistently accounted for the largest percentage of all industrial accidents. In fact, over 25 percent of all industrial accidents are related to handling of materials.4 In underground coal mining operations, material handling accidents account for even larger percentage of lost time injuries. In 1983, for example, they accounted for 34 percent of all lost time injuries and 32.6 percent of all non-lost time injuries. 5 I want to use one example of a task that will illustrate what I have just said: the building of a concrete block stopping. Each solid concrete block will weigh from 60 to 70 pounds. To build a stop- ping 6 feet high and 20 feet wide will take approximately 80 blocks. On the average, these 80 blocks will be handled at least four times from loading into the conveyance for transportation to being placed while constructing the stopping. This generally requires repetitive lifting from ground level. The next three slides demonstrate the lifts

Jan 1, 1986

By Mark Springett

Microcomputers have rapidly evolved to the level at which they can perform almost all of the computational tasks required for exploration, evaluation and exploitation of mineral deposits. The present capabilities of microcomputers are reviewed by examining their use on typical projects from the initial capture of exploration data to the subsequent technical and financial evaluation by microcomputer. Emphasis is placed on the need for compatible software and on the importance of a consistent hardware acquisition policy.

Jan 1, 1987

By Richard H. Adams

INTRODUCTION With the discovery and depletion over the years of near surface ore bodies, exploration targets are tending to be at greater depth or overlain by various types of overburden which in some cases extends to considerable depth or is heavily water bearing. Access to these types of deposits for exploration and development often requires vertical shafts. This paper discusses the concept of small shaft engineering and construction, primarily for underground exploration but also for use as a low tonnage production facility or for mine ventilation. The option of a small shaft may be attractive in a number of cases, some of which are: The underground exploration of a deposit at depth where minimal expenditure is desirable until the potential of the deposit has been determined. The exploration shaft in many cases later serves as a ventilation way and second means of egress. Production of ore in a small tonnage/high-grade operation where decline access is impractical. For ventilation where other types of openings are impractical or would delay start-up of mine operations.

Jan 1, 1987

By P. J. Bethell

This paper reviews current fine coal cleaning circuitry, including water washing cyclones, tabling and froth flotation. It goes on to examine possible future beneficiation based on emerging technologies. Circuits considered include those incorporating spirals, fine heavy medium cycloning, hydrosizers and column flotation.

Jan 1, 1988

By Christopher J. Hall

This paper describes the results from computer runs simulating 24 different mine ventilation configurations with the main fan situated first at the top of the upcast shaft and then at the top of the downcast shaft. Real air was used, with evaporation, condensation and heat exchange. The results showed that power requirements for the forcing fan were up to 20% less than for the exhausting fan for equal mass flow rates.

Jan 1, 1989

By Ugo Preti, Gianfranco Ferrara, Mark C. Williams, Thomas P. Meloy

Theoretical and experimental lockedness profile curves are the same when the model assumptions are met. They appear different because of the way the data is presented. Continuous theoretical lockedness profile curves present all the data, including the wings of the curves giving them the deep U-shaped configuration. Experimental lockedness profile curves, because of the measurement methods, are discretized, obscuring the wings. If the continuous theoretical curves are discretized, they are similar to the experimental curves. When a float sink test is used to measure an interval of locked particles, the integrated averaging of the separation process obscures the wings of the continuous theoretical curve. To disclose the wings with experimental data, narrow density or measurement intervals must be used.

Jan 1, 1992

By William P. Shinn

The site of Pittsburg from the first knowledge by white men of its location has been regarded as a position of great strategic importance.

By Z. Rogovin

In order to develop more accurate procedures for scale-up and design of semi-autogenous-grinding mills through detailed mathematical models, a better understanding of the charge motion and rock/ball segregation is needed. To achieve this a 0.61 m (2.0 ft) diameter x 0.305 m (1.0 ft) length plexiglas mill was constructed as a scale model of a commercial SAG mill. Rock motion in the rotating mill was simulated using various sizes of ceramic balls. Quantitative measurements of dynamic angle of repose, water and slurry motion, holdup and size segregation of the charge were taken. In addition, a video-presentaiton (available to the public) was prepared to elucidate charge and water motion at various mill speeds, charge volumes, rock size distribution and flow rates.

Jan 1, 1985