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By A. E. Back

A method is described in which particulate iron, as distinguished from high purity iron powders used in powder metallurgy, is a precipitant for copper contained in dilute solutions. A new precipitation apparatus utilizes particulate iron precipitants to recover copper more efficiently than is possible in a conventional launder precipitation plant. In the search for lower cost methods of recovering copper from mine water, the use of sponge iron or particulate iron (as distinguished from iron powder used in powder metallurgy) as precipitants in place of tin cans, detinned scrap iron, or scrap iron is an intriguing possibility. The relatively faster copper precipitation rate obtained with particulate iron as compared to scrap iron promises economic and processing advantages when, and if, particulate iron becomes competitive cost-wise with available scrap iron. Kennecott has developed a precipitation cone,' see Fig. 1, utilizing various particulate iron precipitants and has demonstrated the process successfully in a prototype at a flow rate of approximately 1000 gal of solution per min. Essentially complete precipitation of copper is obtained, the cone overflow solution is clear and contains no particulate copper, and the iron factor is more favorable than in a conventional launder plant. Initially, sponge iron produced at the Ray Mines Div. Kennecott Copper Corp. for use in a Leach-Precipitation-Flotation process was used in exploratory tests to develop a suitable apparatus to take advantage of the rapid precipitation rate and efficient iron utilization for the recovery of copper from dilute solutions. Here it was demonstrated that, when sponge iron was added to a launder, the particles of iron collected in the bottom of the launder and tended to cement together. This resulted in incomplete precipitation of the copper and inefficient utilization of the iron. Next, sponge iron was suspended in glass columns to study the dynamics of the precipitation reaction. Again it was observed that the particles tended to cement together at low solution flow rates, while at higher flow rates large amounts of the precipitant overflowed the column, resulting in loss of precipitant and an inefficient process. Next, the precipitant was suspended in an inverted cone in a rising column of solution. Dynamic suspension of the solids was maintained at relatively rapid solution flow rates with instantaneous and complete precipitation of copper and with improved iron utilization. The first tests were conducted on a batch basis and it was determined that a dynamically suspended bed of precipitant was necessary for satisfactory operation. More than 99% of the metallic iron could be converted to metallic copper by careful control of the residence time in the cone and copper precipitation was essentially complete, even when the available iron precipitant was almost depleted. Several cones were built, ranging in capacity from 1 to 200 gal of feed solution per min, and finally, a prototype cone was constructed which was 20-ft high

Jan 1, 1968

By W. J. Carlson, S. M. Parmerter, I. Iwasaki

This article discusses the effect of physical and chemical modifications of starches on the anionic and cationic flotation of silica from oxidized iron ores and magnetite-taconite concentrates. It also deals with the results of the interaction of starch, pH, and calcium ions on the flocculation, clarification, and filtration of iron ore slimes and magnetite-taconite tailings. Starches, particularly when an-ionically modified, were found to be effective depressants in anionic silica flotation. British gums and dextrins were beneficial for oxidized iron ores, but none of the starches or starch derivatives appeared to have any effect on magnetite-taconite concentrates. The flocculation and filtration of iron ore slimes were affected most strongly by the level of starch, to a lesser degree by the pH, and virtually not at all by the level of calcium chloride. The clarification of iron ore slimes was complexly dependent on these three factors. The flocculation of magnetite-taconite tailings depended mainly on the level of starch, whereas their clarification depended on the level of lime. As previously reported in the literature, selective flocculation and partial upgrading of a semitaconite could be readily attained with starch and calcium chloride. A previous article discussed some of the parameters that are important when various corn starches are applied to the soap flotation of activated silica from iron ores and to the flocculation of iron ore slimes.' Methods of solubilizing the starches and the molecular size after mechanical and thermal treatments, as inferred from the viscosity measurements, were shown to influence the adsorption characteristics on iron ores, and the residual concentrations of both calcium ion and starch in the pulp liquor were in direct correlation with the flotation and flocculation behavior.2-4 The present article summarizes the results of more recent tests conducted to ascertain the role of starches and starch derivatives in various phases of iron ore beneficiation. The scope of this investigation has been extended to include not only anionic and cationic flotation, but also the flocculation and filtration of iron oxide slimes, the selective flocculation and partial upgrading of semitaconites, and the flocculation and clarification of magnetite-taconite tailings —all problems that are of vital importance to the iron ore industry of Minnesota. By combining a practical approach with adsorption studies and by using single-mineral systems5 in these research efforts, it is believed that the ultimate goal of developing a suitable modification of starch structure may be realized. The topics covered in this article are limited to the empirical aspects of the research program on the depressant activity of starches and products in the cationic and anionic flotation of silica and of their role in flocculation, water clarification and filtration. ANIONIC SILICA FLOTATION In the soap flotation of activated silica from iron

Jan 1, 1970

By S. A. Ronlov

The importance of recognizing vibration problems during the plant design stage is emphasized in this paper. Often an experienced designer can recommend what type of support to use and how to tune the structure. However, obtaining sufficient information is a serious problem dealing with vibration. Vibration is a well known phenomena which, simply and generally, can be defined as a periodic motion. It is experienced in nature as caused by eerth- quake, wind, or ocean waves, and must be dealt with in the design of structure or ships. It must be realized that wherever there are moving or rotating elements, it is possible that unbalanced forces may induce vibration in the elements themselves, in adjacent parts, or in the supporting structure. Under certain circumstances, vibration will destroy machines or structures quickly and totally. The most widely known case is the total collapse of the Tacoma bridge when subjected to a wind of only 42 mph. Failures due to vibration of machines and/or their supports may occur in industrial plants where heavy equipment employed in the process must be supported and several machines are combined in close proximity. In the Metallurgical and Chemical Div. of The

Jan 1, 1962

By L. D. Lash, J. R. Ross

Discovery of scandium in the Vitro solvent extraction plant for uranium led to commercial recovery of the byproduct. Micro amounts of scandium were extracted with uranium by dodecyl phosphoric acid, but failed to follow ura-niuminto the hydrochloric acid strip solution and were eventually concentrated in the organic extractant. A fluoride strip system was developed to recover scandium from the solvent in concentrated form. High purity scandium oxide was then prepared in multi-pound lots by chemical separation techniques. The plant recovery operation, final product purification, and analytical procedures are described. Scandium is a pseudo-rare earth which is truly rare and expensive. It has special properties which may make it desirable even at the present price of $2750 per lb. Recently the price was lowered from $5000 per Ib which had prevailed since 1952, and it is anticipated that usage will be stimulated because of the lowered price. This metallic element is distributed widely in trace amounts in the rocks of the earth's crust. In addition to micro-amounts found in most uranium ores, concentrations of 50 to 100 ppm have been found in Colorado ferberite ore, lateritic nickel ore, heavy sandstone from Utah, Wyoming, and New Mexico, and various zircon sands and monazites from the western part of the U. S. Scandium has been found as an essential constituent of very few minerals, the most important being thortveitite, a scandium silicate. At the present time, this mineral commands a price more than twice that of gold. Chemically, scandium is in group 3A of the periodic table. It is closely associated with yttrium and the rare earths which it strongly resembles in its reactions. It has a valence of three and will form an insoluble hydroxide, fluoride, or oxalate under proper conditions, similar to the rare earths. Eight years before its discovery, scandium was predicted by Mendeleef who ascribed his eka-boron with properties nearly identical to the actual properties of scandium. Its position as the element with Atomic No. 21 and Atomic Weight 44.96 places it between calcium and titanium in Period 4 of the chart. The successful commercial application of scandium must depend on unique properties to justify use of this high cost substance. Greater consumption would allow additional price reductions, but scan- dium will remain a relatively high-priced commodity because of its inherent scarcity. Research reportedly has been oriented toward use of scandium as an agent to achieve high-temperature, low-density alloys with magnesium and tantalum.' Also, the U.S. Air Force sponsored a project for production of research amounts of pure scandium metal.' The oxide has been used experimentally in electronics, ceramics, and metallurgy. The various aspects of scandium are well covered in recent publications.s-5 CONCENTRATE RECOVERY Small amounts of scandium exist in uranium ores and are dissolved during an acid leach yielding up to 0.001 gpl Sc2O9. When Vitro converted their uranium plant from phosphate precipitation to solvent extraction: scandium was found to follow the uranium into the dodecyl phosphoric acid solvent (DDPA). However, scandium did not strip with uranium from the DDPA in hydrochloric acid, but remained in the solvent. Therefore, a concentration of scandium built up in the organic phase. Residues from the solvent were spectrographed by the U.S. Bureau of Mines and found to contain scandium. As a result of this discovery, provisions were made in the plant for recovery of scandium-bearing concentrates. Solvent extraction of uranium was added to a conventional acid leach process in a typical installation? The ore was crushed and ground, and then leached with dilute sulfuric acid. Addition of an oxidant such as sodium chlorate insured conversion of uranium minerals to a soluble form. At this point, the slurry was chemically reduced by a sulfide, such as sodium hydrosulfide, to remove substances such as ferric iron and molybdenum which were partially extracted by the solvent. The solids-liquid separation was accomplished by a four-stage counter cur rent decantation (CCD) thickener circuit. The uranium was extracted from pregnant liquor with 0.1M DDPA in kerosene and stripped with ION

Jan 1, 1961

By D. R. Walker, M. C. Shaw

Dimitri Kececioglu (Allis-Chalmers Manufacturing Co., Milwaukee)—The idea of applying metal cutting theory to comminution and vice versa is very impressive. Among others, the demarcation of wheel-grinding data into two regions, namely Kick's and Rittinger's, draws attention here. A study of Figs. 6 to 9 shows the following: In Fig. 6, 1 point out of 8; in Fig. 7, 4 points out of 26; in Fig. 8 only 1 point out of 13; and in Fig. 9 practically none out of 13 points fall out of curve No. 2. Also when grinding particles smaller than 5x10." in. it is difficult to measure very accurately the grinding forces, chip geometry, and particle size. In view of the above it would be difficult to make a positive and distinct demarcation of the Wheel-grinding data into two regions, namely, Kick's and Rittinger's. The idea of using machine grinding to determine the comminution properties of materials is indeed unique. The following cautions come to mind, however, regarding applicability of machine grinding data to comminution: 1—Grinding gives uniform particle size, whereas comminution gives a variety of particle sizes in the same process. The fact that grinding gives uniform particle size is not necessarily an advantage because in comminution the overall energy under actual comminution is desired and comminution invariably results in the production of a variety of particle sizes. 2—In grinding, a small particle is ground off a comparatively large surface. In comminution small bodies are broken down to smaller bodies. This makes it difficult to establish a concept of reduction ratio in machine grinding. 3—The mechanics of machine grinding involve direct shearing action under very high strain and comparatively high compression at the shear zone, whereas: comminution involves direct dynamic compression and surface friction with comparatively little strain and shear. Consequently the mechanics of machine grinding appear to be different from those involved in comminution. Hence one might arrive at erroneous con- clusions when comminution characteristics are eval-uated from machine grinding results. It is noticed also that functions other 'than Eq. 16 which do not involve the concept of direct proportionality of useful energy input to new surface area created (Eq. 2 and particularly Eq. 12) may be derived to fit the, data of curve No. 2. One such relationship may be u = ct-", where c is a positive constant and n is a positive constant less than unity. This, of course, is made possible because data of a very small range. of particle size are being fitted by the curves of No. 2 and the hereby suggested relationship. A sound comminution theory should be applicable to a relatively large range of particle size. George B. Clark (Department of Mining Engineering, University of Illinois)—While the experimental work of Walker and Shawin this article is of intrinsic value in revealing certain fundamental aspects of machine grinding, milling, and related processes and in adding to the store of information concerning the comminution of solid materials by this particular process, it appears doubtful that the results of their research can be employed to verify either Kick's or Rittinger's theories. Both these laws were originally developed and proposed on the basis of very simple, idealized hypotheses. The creation of parallel idealized physical laboratory conditions which would be required for either their proof or disproof appear to be well beyond the scope of human ingenuity, at least at present. One great weakness of the imputed verification is that the spread of the points plotted on the graphs is not sufficient to permit accurate 'curve fitting. The range of particle sizes included in the belt and wheel grinding is not extensive enough to show any general trends, particularly for the horizontal portion of the curves, said to represent Kick's laws. That the milling; grinding, and turning data obtained by Walker and Shaw for both metals and minerals happen to comply with. certain interpretations of these two theories under certain specialized conditions

Jan 1, 1955

By Fred C. Bond

SIX years have passed since the last grindability table was published.' In that time the list has been increased with many new tests, and the development of the new Third Theory of Comminution2 has made possible the reduction of all results to a consistent work index value. In this tabulation all grindability and crushability test results are given in terms of the work index, with formulas for reversion to the older units if desired. The average values for 57 different classes of materials are listed in Table I. The total number of work index values listed is 1211, and the overall average work index is 14.42. The complete tabulation, with each test listed alphabetically both under material type and under company name, can be obtained by writing to the Allis-Chalmers Manufacturing Co., Processing Machinery Department, Milwaukee 1, Wisconsin. The work index Wi is the calculated total work input in kilowatt-hours per short ton required to re- duce from theoretically infinite particle size to 80 pct passing 100 microns, or to approximately 67 pct passing 200 mesh. The work inputs required per ton for the same size reduction of different materials are directly proportional to their work indexes, and according to the Third Theory the work input per ton is inversely proportional to the square root of the diameter of the product particles. Where W represents the work input in kilowatt hours per ton, where F is the feed size, or diameter in microns of the square hole which 80 pct of the feed passes, P the product size, or microns which 80 pct of the product passes, and Rr the reduction ratio F/P, the work index Wi is found from Rr-l 100 When the work index Wi is known, the work input W required to reduce from any feed size F to any product size P is found from W = Wi ( Rr- 1 100

Jan 1, 1954

By F. F. Aplan

Mineral processing engineers have recorded an- other year of active research and development work. Most gratifying was the broadly based attendance at the Mineral Processing Fundamental (formerly Basic Science) Committee sessions at the 1968 Annual Meeting of the AIME. Because of the availability of good papers, the active discussion and the growing attendance, sessions have grown from one to three at the annual meeting. Prof. M. C. Fuerstenau of the University of Utah will chair the Mineral Processing Fundamentals Committee for the next two years and we may thus be assured of continued active leadership. The name change from "Basic Science Committee" to the more descriptive "Mineral Processing Fundamentals Committee" approved by the MBD executive council is a welcome improvement. Our profession continues to attract the interest and cooperation of those in other professional groups. The 1968 Engineering Foundation Particulate Matter Conference, under the chairmanship of John Karpinski of Bethlehem Steel, was devoted exclusively to comminution this year. It attracted conferees from five continents and served as a particularly stimulating source of interchange of knowledge from many technical fields. Next year's conference will be under the chairmanship of Professor L,. G. Austin of The Pennsylvania State University. This conference plus the Symposium on Wettability and Flotation to be held at the annual American Chemical Society meeting in Minneapolis in April indicates the success achieved in the inter-disciplinary approach to problems. Other evidence of this spirit of professional cooperation is the forth- coming book on Size Reduction edited by D. W. Fuerstenau. This is the outgrowth of an AIChE symposium on size reduction held in 1965.

Jan 2, 1969

By Donald A. Dahlstrom

In 1961 it became increasingly more evident that significant technological changes must be made in minerals beneficiation. The status quo in technology in today's competitive markets will not be tolerated. Higher productivity, greater recoveries and newer and better products must be sought and incorporated with lower operating costs. In other words, "when you build a new mill, don't build an old mill." Recommended reading for proof of the vital necessity of new methods and techniques is in the September 1961 issue of MINING ENGINEERING. The article by one of MBD's cherished and true veterans, E. H. Rose, is entitled "Iron Ore: The BIG Picture". Because of new beneficiation methods for iron ores, nearly 47 million tons of plus 60% iron concentrates will be produced and another 40.1 million tons of capacity will be under construction or committed. Thus in a relatively short period, 87 million tons of this high-grade iron concentrate with record low silica will be available. As Mr. Rose also points out, "in gross tons, without allowance for better grade, this is the equivalent of almost exactly two-thirds of all iron ore used for all purposes in the U.S. and Canada in the peak years of 1953 or 1957." Needless to say, improved mineral beneficiation methods have had far more reaching effects than just the production of higher grade iron concentrate.

Jan 2, 1962

By F. T. Davis

Many contributors have added to the fund of knowledge in the basic sciences related to mineral dressing during the past year. During 1964, the French edition of the Proceedings of the VIth International Mineral Processing Congress together with discussions was printed. Also, complete Preprints of papers delivered at the VIIth IMPC were published in September1. Over a third of the papers presented at VIIth IMPC dealt with fundamentals. COMMINUTION It has been postulated by Ponceleta that flaws need not exist before a stress is applied but rather the flaws are created at the tip of a propagating crack at a stress well below the theoretical breaking stress.

Jan 2, 1965

By J. M. Karpinski, R. O. Tervo

A method and equipment have been developed for measuring the impact strength of grains of brittle materials. It is shown that brittle materials develop a characteristic particle size distribution when fractured by impact. A simple mathematical model has been found to describe this distribution, and one of the parameters of the model has been designated the r value. The r value is directly proportional to impact energy and, for fixed impact energy, it becomes a useful criterion of grain strength. Data are presented on the variation of the r value as a function of sample history, initial size, energy input and number of impacts. The results are interpreted in terms of the flaw theory of brittle fracture. The view is now widely held that brittle materials comprise a strong matrix, throughout which flaws or points of weakness are scattered at random. Failure always starts at one or more of these imperfections, and planes of fracture are established by the geometry of the flaw distribution. This view has been developed extensively by Weibull 1,2 and experiments of a confirmatory nature have been reported.3,4 Thus the process of fracture or size reduction of brittle materials can be regarded as a process of elimination or creation of flaws, and the concept of strength is intimately connected with the size and history of the specimen tested. One consequence of the point of view described above is that brittle materials will fracture to yield similar size distributions, although the impact energy to produce a given amount of fracture may vary greatly from one material to another. Generally speaking, experimental investigations of brittle fracture in solids have been confined to two extreme experimental situations. On one hand, we have tests on single specimens of well-defined, but artificial, geometry and, on the other, empirical data have been obtained on the feed-product relation in a variety of mills. The first situation necessitates specimen preparation, which in the case of brittle materials is equivalent to a priori size reduction, while the second one suffers from the disadvantage that little knowledge is gained about individual fracture events. Also, the statistical significance of single specimen tests may be questioned. Our approach lies somewhere between these two extremes. We test a large population of sized specimens and yet subject each specimen to a single fracture event. In 1956 G.H. Fetterley of Norton Co., Chippawa, Ont., made the empirical observation that product size distributions obtained from impacting sized grits can be described by the following equation where R is the proportion by weight of the grain that remains on a screen having an opening x on a side, x, is a parameter having the dimensions of length, and r is a number. This equation has since been derived on a theoretical basis by Gaudin and Meloy.5 They identify x, with the initial size of the test piece and r with the number of flaws per unit length. As will be shown below, our experiments indicate that both x, and r are functions of energy and hence they should more properly be called the effective initial size and the effective number of flaws respectively. Also, our empirical data give us no basis for assuming that r represents the effective number of flaws per unit length, rather than per unit volume. METHOD AND MATERIALS The impact test machine has been designed to feed specimens, essentially one at a time, into an evacuated chamber, where they fall freely and are struck with random orientation by one or the other of a pair of flat steel vanes. The vanes are mounted at opposite ends of a steel bar, which rotates at a closely controlled angular velocity about a vertical axis. Fig. 1 shows the flat circular vacuum chamber with the cover removed, and the horizontal steel bar with the steel vanes at the ends. The cylindrical pot in which the grains are collected after impact appears at the left. Fig. 2 shows the equipment assembled for a test. The vacuum chamber occupies the central position with the variable speed drive below the table surface, the vacuum pump at the extreme left

Jan 1, 1964

Mining education in Ballarat has a long and proud history dating back to the 1870s. Today the School of Engineering continues this tradition at the University of Ballarat. The recent review of Tertiary Minerals Education by the Minerals Council of Australia has questioned the current situation regarding Minerals tertiary education in Australia and recommendations have been made regarding the future of minerals tertiary education. This paper initially examines the original recommendations made by the Minerals Council of Australia and assesses subsequent changes made to these recommendations. Secondly the paper outlines the future shape of mining education in the light of these recommendations given that they are implemented. Finally the future delivery of mining education is discussed, particularly with respect to the impact of modern technologies.

Jan 1, 2004

By Dan Witkowsky

In an increasingly environmentally conscious world, mining's importance to society has often been misunderstood and even maligned by the public. Extreme and impractical ideas have often been presented to children because of the lack of accurate, timely resource materials available to educators. In the late 1960s. two mining engineers, S.P. "Pi" Warren and C.L. "Lindy" Barker, became aware of this situation. They proposed to develop a summer field course to provide a factual overview of the minerals industry for teachers. The pair believed that teachers could become better informed to educate students, and future generations, about mining. These two Colorado Mining Association (CMA) members felt that such a course could reduce much of the misunderstanding about this vital industry. This could be done by providing a balanced perspective of mining, not only for kindergarten-through-grade-12 teachers, but also for the students they would be teaching during their careers. Students who better understood the minerals industry could better formulate an unbiased view of it. The course would seek recognized authorities from industry, academia and government who would lecture in their respective fields of expertise. The course would provide a total concept of the coal, aggregate, metals and industrial minerals industries. It would include geology, geophysics, exploration, mining, processing, marketing, product applications, economic, mining history, careers, and environmental responsiblity. When possible, site visits would permit educators to view operations and to meet the men and women who are industry leaders. Teachers would pay a small tuition fee. The balance of the program expenses for each teacher would be paid through scholarships provided by industry and individuals. The "total concept" idea obtained the support of the minerals industry. The support of CMA's Education Committee and the Colorado School of Mines (CSM) was obtained in 1968. Colorado's Commission on Higher Education approved teacher recertification credits through CSM's Office of Special Progams and Continuing Education for those successfully completing the program. The first six-week series of classes presenting the total concept of the indus¬try was held at CSM in 1969. In 1977, the CMA Education Foundation Inc. (CMAEF) was established as a Colorado nonprofit corporation. The "Total Concept of the Mining Industry" (Total Concept) course was placed under its sponsorship. CMAEF is dedicated toward this continuing education program (Table 1). In 1994, the course was streamlined to four-weeks for six hours recertification credit.

Jan 1, 1997

By Robert A. Clifton

It seems probable that more and more minerals will be used in plastics as time goes on. This must occur because the minerals will; aid in processability, enhance the engineering properties, reduce the cost, and above all conserve large amounts of petroleum based chemicals. This paper examines the advantages and disadvantages of using the minerals and the ability of the domestic minerals industry to support this possibly very large undertaking. In the author's opinion, it can. This talk is excerpted from a forthcoming Bureau of Mines Information Circular.

Jan 1, 1985

'Industrial Minerals - their mining and use in New Zealand' is the theme of the 1978 Annual Conference of the New Zealand Branch of The Australasian Institute of Mining and Metallurgy. This paper describes the use of phosphate rock, sulphur and potassium chloride (potash) - three industrial minerals which have enabled the farmers of New Zealand to increase production to current levels. The growth of imports of these raw materials for the New Zealand fertiliser industry is well documented in NZ Fertiliser Statistics 1977. This is the most recent of the Ministry of Agriculture and Fisheries annual publications on this Subject prepared from the detailed returns of fertiliser manufacture and sales from each fertiliser works. There are now 12 of these works in New Zealand one of the most recently established being in Whangarie where this conference is being held. Its capacity to manufacture superphosphate will shortly be 300 000 tonnes twice that when it opened late in 1964. New grinding and manufacturing equipment comes on stream early in 1979. This paper illustrates the interdependence of two primary industries, agriculture and mining. New Zealand's economy in the foreseeable future will be based on agriculture so that our standard of living is dependent on the overseas prices and freight costs of the bulk raw materials from which our fertilisers are made. For the year ended 31 March 1978 New Zealand's total exports were $3395 million, of this total $2413 million (71%) came from the products of pastoral agriculture (wheat, wool, dairy and other animal products), $291 million from forest products and $501 (15%) from manufactured exports. Approximately half of the pastoral receipts can be attributed to the fertilisers applied at a total cost of about $200 million including subsidy.

Jan 1, 1978

By W. Lorenz

The responsible treatment of natural resources, including mineral raw materials, contributes to the protection of the environment. The management of resources and the environment encompasses reduction of emission through application of environmentally friendly processes, economical use of resources, recycling and substitution, application of energy saving processes, land reclamation and recultivation, as well as a well balanced regional and land use planning. A variety of materials are needed for measures to protect the environment. Many of these materials are, or to a large percentage consist of, mineral raw materials, which become effective either directly or indirectly in their natural state or after an appropriate industrial treatment. We call them environmental minerals. Although extraction and processing of these mineral raw materials destined for use in the protection of the environment, may have a negative impact on the environment on one hand, preventive or curing measures to protect the environment on the other would not be possible without them. We have to accept certain smaller burdens of the environment, which naturally will have to be kept at the lowest possible level, in order to avoid or minimize greater damages to nature. In the broad group of industrial minerals and rocks there is a wide variety of mineral raw materials, which lend themselves for countermeasures in favor of the environment. To hamper their production and processing through excessive environmental regulations would make the protection of the very environment more difficult or even impossible.

Jan 1, 1995

By H. Foster Bain

FROM time to time geologists and mining engineers, impressed by the heavy demands made on our mineral reserves' by modern industry, and particularly by the steadily mounting rate of production necessary to meet that demand, have issued warnings as to the danger of exhaustion. There can be no dispute as to the fact that mineral deposits are exhaustible. New mineral, is not created to replace that taken from the earth and when a crop of mineral is once harvested another cannot be grown in the same area. The evidence of exhaustion 'of particular oreshoots, deposits, or even of whole districts is familiar to all who have mined. If one were to judge solely from the abandoned mills and prospect holes he would rightly conclude that mining is but a short-lived industry. If one were, furthermore, to assemble the data as to known reserves of almost any of the commonly used minerals, and divide them by the annual tonnage mined, he would come to the same conclusion. If, again, one were to consider the most carefully made estimates of competent men seeking to measure the earth's reserves of minerals and plot against them a projection of the curve of past consumption, he would be justified in viewing the situation with alarm.

Jan 1, 1930

By Zay Jeffries

From the title of this chapter the reader could expect an attempt to outline the anticipated shape of things to come, mineralwise. We have no crystal ball and if we possessed one we could claim no expertness in its use. In the first place no one can tell the future status of man. No one has any way of knowing to what extent peace will prevail, nor to what extent changes may occur in national sovereignties or forms of government or in international relationships. So future man is an uncertainty. Nor can we predict new developments that may result in significant changes in man's status or in the mineral industry or both. If, for example, this chapter had been written in the middle 1930's, nearly everything that has happened since in the field of atomic energy would have been missed. Yet what a vast change this has made in the status of man! Also the changes in the mineral industry have been important. A writer would have been bold indeed had he prophesied that uranium would play such an important role. But we need not confine our foggy vision to the atomic energy field. The steep rise in the use of aluminum, titanium, and germanium reflects the unpredictable in what may be thought of as the more normal pursuits. This should not discourage one from using the past and currently observable trends as bases for limited predictions. To do this, however, it is desirable to make certain assumptions about man's status without even a pretense that these assumptions have a high probability of fulfillment: 1. Only minor changes will occur in the geographical boundaries of the nations of the world. 2. World War III will not take place in the near future. 3. As a consequence of (2), man will not destroy himself by wanton use of atomic weapons. 4. Disarmament will take place, if at all, gradually rather than all at one time. Under the above assumptions the world will enjoy a period of relative peace even though the status may be one of an armed truce. The assump-

Jan 1, 1959

By Zay Jeffries

From the title of this chapter the reader could expect an attempt to out- line the anticipated shape of things to come, mineralwise. We have no crystal ball and if we possessed one we could claim no expertness in its use. In the first place no one can tell the future status of man. No one has any way of knowing to what extent peace will prevail, nor to what extent changes may occur in national sovereignties or forms of government or in international relationships. So future man is an uncertainty. Nor can we predict new developments that may result in significant changes in man's status or in the mineral industry or both. If, for example, this chapter had been written in the middle 1930's, nearly everything that has happened since in the fields of atomic energy and space technology would have been missed. Yet what vast changes these I have made in the status of man! Also the changes in the mineral industry have been important. A writer would have been bold indeed had he prophesied that uranium would play such an important role. But we need not confine our foggy vision to these fields. The steep rise in the use of aluminum, titanium, and germanium reflects the unpredictable in what may be thought of as the more normal pursuits. This should not discourage one from using the past and currently observable trends as bases for limited predictions. To do this, however, it is desirable to make certain assumptions about man's status without pretense that these assumptions have a high probability of fulfillment: 1. Only minor changes will occur in the geographical boundaries of the nations of the world. 2. World War III will not take place in the near future. 3. As a consequence of (2), man will not destroy himself by wanton use of atomic weapons. 4. Disarmament will take place, if at all, gradually rather than all at one time. Under the above assumptions the world will enjoy a period of relative peace even though the status may be one of an armed truce. The assump-

Jan 1, 1964

By Elmer W. Pehrson

Minerals have played a prominent role in the affairs of man and nations since time immemorial but with the advent of the industrial revolution, expanding use of the products of the mineral kingdom became synonymous with the material progress of mankind. Individuals and business groups have recognized this fact so have been aggressive in searching for and utilizing mineral resources, with notable success. Indeed, their achievements are primarily responsible for the present Machine Age. On the other hand, until recently the body politic has failed to grasp fully the essentiality of minerals although, at times, access to mineral supplies has been an important factor in the political maneuvers of nations. This chapter is concerned primarily with the broader political and economic relationships of mineral resources to the world economy, and with the internal and external actions of nations in the field of minerals. Many factors that condition the mineral economy of regions and the world as a whole, influence the internal and external affairs of individual nations. The more important of these are: 1. The nature of man's dependence on minerals. 2. The problems resulting from the unique characteristics of mineral occurrence. 3. Geopolitical concepts. 4. Minerals and world power. Actions of individual nations affecting their mineral economy seek two basic objectives : 1. Attainment and maintenance of prosperity. 2. Military security. Other objectives may be cited but on careful analysis they become integral parts or extreme phases of the two points noted above. For example, the twentieth century aggressions of the USSR, Germany, Italy, and Japan might be considered as direct bids for world power but they also can be interpreted as exaggerated or mistaken efforts toward military security and peacetime prosperity. Similarly, trade barriers, nationalization of industries, foreign exchange manipulations, taxation, monopolistic prac-

Jan 1, 1959

By Elmer W. Pehrson

Minerals have played a prominent role in the affairs of man and nations since time immemorial but with the advent of the industrial revolution, expanding use of the products of the mineral kingdom became synonymous with the material progress of mankind. Individuals and business groups have recognized this fact so have been aggressive in searching for and utilizing mineral resources, with notable success. Indeed, their achievements are primarily responsible for the present Machine Age. On the other hand, until recently the body politic has failed to grasp fully the essentiality of minerals although, at times, access to mineral supplies has been an important factor in the political maneuvers of nations. This chapter is concerned primarily with the broader political and economic relationships of mineral resources to the world economy, and with the internal and external actions of nations in the field of minerals. Many factors that condition the mineral economy of regions and the world as a whole, influence the internal and external affairs of individual nations. The more important of these are: 1. The nature of man's dependence on minerals. 2. The problems resulting from the unique characteristics of mineral occurrence. 3. Geopolitical concepts. 4. Minerals and world power. Actions of individual nations affecting their mineral economy seek two basic objectives: 1. Attainment and maintenance of prosperity. 2. Military security. Other objectives may be cited but on careful analysis they become integral parts or extreme phases of the two points noted above. For example, the twentieth century aggressions of the USSR, Germany, Italy, and Japan might be considered as direct bids for world power but they also can be interpreted as exaggerated or mistaken efforts toward military security and peacetime prosperity. Similarly, trade barriers, nationalization of industries, foreign exchange manipulations, taxation, monopolistic prac-

Jan 1, 1964