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By W. F. Dietrich

Mineral fillers are relatively inert chemically under the conditions of use but have physical properties* that modify those of the materials • The properties. uses, and other data on 15 classes of important *The pro listed in the second edition of Industrial Minerals and Rocks.l A third edition of this reference is in preparation. in which they are incorporated. The mineral fillers considered in this article are asbestos, barite, clays, diatomite, crushed limestone, limestone whiting and lime, mica, silica, talc and soapstone, and pyrophyllite. Slate and stone, other than limestone and its derivatives, are excluded because, even though used in large quantities, they are exceptionally low-cost materials generally produced close to the area where they are used. Carbon black is excluded because it is manufactured from natural gas and more than 90 pct of the output is used in rubber; hence the factors for estimating requirements are easily evaluated. OVERALL GROWTH FACTORS Table I gives the population, retail sales, and value added by manufactures in the U. S. and in the eleven western states in 1954. These data are rough guides to the proportionate part of total U. S. markets for products containing mineral fillers that may be expected in a given area. For example, the population of the eight Mountain states in 1954 was 3.6 pct, and retail sales in these states were 3.8 pct of the U. S. total, but the value added by manufactures was only 1.3 pct of the U. S. total. On the other hand, the three Pacific Coast states, with 10.3 pct of the total population, had 12.0 pct of the retail sales and produced 9.6 pct of the value added by manufactures. On an industry-by-industry basis the correlation between the three guideposts will not be as close as shown in the 1954 data for the Pacific Coast states, but in the long-term view the continuing rapid population growth in the western states is certain to result in expanded industrial production at an even more accelerated pace, which will shorten the gap between local consumption and production in most major groups of manufactured consumer goods. Of course, there will always remain favorable areas for production of specific products. Such special situations must be individually analyzed. Fig. 1 compares the population trends in the U. S., the western states, and California with Real Gross National Product from 1910 to 1957, with forecasts to 1970. It is estimated' that the U. S. Real Gross National Product, as measured by the value of goods and

Jan 1, 1960

By William P. Shinn

Jan 1, 1881

By C. Schlumberger, M. Schlumberger

The object of this paper is to clarify the idea, so important when exploring by potential methods, of the depth of investigation attainable by electrical measurements. After defining, with some precision, .the term "depth of investigation'' in geophysics, the authors show how it is possible to regulate this depth in potential methods and to obtain an 'electrical drilling" from surface observations. They consider also the difficulties encountered in deep measurements and indicate how it is possible to reach greater depths than those having an industrial interest. Depth of Investigation The term, depth of investigation, in its general sense, is easily understood. For instance, a driller who can pull cores from a depth of 2000 m. is capable of working, with accuracy, to that depth. By means of a properly placed drill, he may locate an orebody at a depth of 1999 m., however small this orebody may be. On the contrary, the term as used in geophysics requires precise elaboration. As a matter of fact, no geophysical method, irrespective of the physical property studied (density, magnetic permeability, conductivity), can discover a very small body at a great depth because, in practice, the physical parameter upon which such a geophysical method is based is never regular enough, throughout the ground, to distinguish the feeble anomaly caused by the small, deep-lying body from the numerous anomalies due to irregularities of the encasing terrains. Aside from this question of the ratio between the size of the body being hunted for and its depth of burial, a second factor plays its role in the possible depth of investigation; that is the difference, for the parameter under consideration, between the body and its surrounding material. The greater this difference, and the more homogeneous the encasing terrains, the greater is the possible depth of investigation. This being generally established for all geophysical methods, it is possible to distinguish two main classes of these methods, from this same point of view

Jan 1, 1932

By George S. Koch

Since 1882, world zinc production has increased. In contrast, US zinc production rose until about 1915, but since then has remained nearly constant, with a slight tendency to decrease. Production from the Tri-State district, the largest early source of zinc in the US, has gone down steadily; this decline has been balanced by a growth in the rate of other districts. These changes in US production are due to economic, not geological, factors. Recent exploration has located large minable ore bodies: additional deposits will undoubtedly be found in the stratabound carbonate rock and volcanogenic environments. A statistical analysis of the exploration effort in the Middle Tennessee district indicates that new discoveries can be expected there. Thus, the US is in an early stage of the production cycle for zinc. Of major mining districts in the US, only the Tri-State is exhausted under current economic conditions; large zinc resources of low-grade material, which would repay mining at higher prices or improved technology, are known to exist in that district .

Jan 1, 1982

By ALFRED T. BARR

In certain areas of the New Cornelia pit, considerable secondary blasting is necessary to reduce oversized boulders, formed from primary blasting, to pieces which will pass the 41/2-cu yd dippers on the shovels. Some of the boulders are 'dobied, but when time permits they are blockholed and blasted. In most instances one hole drilled to a depth of 2 to 3 ft and blasted with 1/3 to 1/2 of a stick of powder will break a boulder satisfactorily. Blockholing is normally done by using a jackhammer of the 55-lb class, 1-in. round drill steel, and detachable steel bits, 2-in. gauge when new. A bit change is usually made after the completion of each hole. The use of light drilling equipment in blockholing is desirable, both from the standpoint of safety and ease of doing the work, and when it was seen there was a possibility of using a lighter jackhammer through the use of tungsten-carbide bits and at the same time get at least the same drilling efficiency as with the standard equipment, it was decided to test tungsten-carbide bits. The claims for long life of the bits and footage drilled before resharpening gave hopes of eliminating much of the delay time in changing bits which is unavoidable with the use of steel bits. and thus gain in actual drilling time.

Jan 1, 1949

By Daryl R. Tweeton, Jerry R. Riding, Grant Buma, Frank J. Rosswog

In situ solution mining of uranium has environmental advantages over conventional mining. The leaching of uranium, however, alters the ground-water quality in the aquifer where the mining occurs. Currently, regulations require that the ground water be restored to approximately its original condition. This paper, a summary of a study funded by the Bureau of Mines, reviews the state of the art in restoring ground-water quality after in situ uranium leaching. Current restoration practices discussed include disposal of liquid wastes in deep disposal wells and evaporation ponds, producing from all wells during restoration, and recirculating water purified in surface plants. Methods for predicting the effectiveness and cost of current techniques are presented. Possible alternative techniques are also described. Two restoration operations are discussed.

Jan 1, 1979

By AIME AIME

AT the end of September, ' the metal-producing industries were almost prostrate, the production of fuels was largely curtailed, there was a fair degree of activity in general manufacturing, while retail trade was moderately good. Looking at industry on the whole, there was a large percentage of unemployment, the degree of which has increased, progressively, month by month since the beginning of 1921. There is the prospect of much destitution and misery this winter; yet while' in some, quarters, idle workers are already being fed from, commissaries; in other quarters profligacy; in "spending continues, unabated. Amid this confusion in conditions there is;' much that appears paradoxical, but in fact it is not so and indeed everything is running pretty true to form: Such activity in production as there is to be seen is mainly in textiles; - leather goods, foodstuffs, etc., i.e., consumption goods for immediate use. Even in hard times 105,000,000 people must buy a good deal of clothing and food. Besides this there is indispensable repair work and- maintenances. Thus, the good business of the year in white lead for painting. The chief uses for the metals, however, are in the production of capital goods, and except for occasional and special reasons nobody in his senses is capitalizing anything at present prices for labor. Hence several millions of men are idle. The impoverishment of Europe and the exhaustion of her credits adds to this by curtailing our export trade.

Jan 1, 1921

By O. P. Chisholm

Dross emerges from the blast furnace either with the lead through a lead well or by tapping from a forehearth or settler, but until a dozen years or so ago few dross reverberatories were used in western lead smelters because it was the usual procedure to circulate the dross from the drossing lead kettles back to the blast furnace. It was quite customary for lead smelters to produce matte in their blast furnaces, as this was the form in which copper could be collected, concentrated if necessary, and shipped to the copper smelters for further treatment. The main prerequisites for good matte formation arc., of course, a more or less definite amount of copper on the charge and sufficient sulphur. Such troublesome impurities as arsenic and antimony were ignored, in so far as possible, although they contaminated the bullion and thereby increased refinery costs. At the same time stocks of blastfurnace speiss containing gold, silver, lead and copper in addition to iron, arsenic and antimony, were being accumulated for want of a market to absorb them. As the dross was being fed back to the furnaces as rapidly as it was being produced, arsenic and antimony tended to build up until the arsenic could effect a combination with copper and iron and an alliance with lead, and the antimony a combination with copper and an alliancc with lead. Sulphur, being the most active agent in taking up the copper, left little of that element for the arsenic and antimony, so that on the whole a somewhat unsatisfactory metallurgy resulted. During this same period, certain lead plants were beginning to encounter trouble with zinc due to the replacement of crude ores of lot zinc content by concentrates containing high percentages of lead and zinc in sulphide form, the blast-furnace slags resulting from the smelting of such concentrates being characterized by a decidedly increased zinc content. It was soon realized that zinc plus sulphur was "poison" to a lead blast furnace and steps were taken to reduce the sulphur content,. At this stage some plants found that any substantial matte fall was out.

Jan 1, 1937

By J. P. Pritchard, J. T. Pierce, O. G. Slay

This paper discusses the results of a technology-evaluation program to ascertain the feasibility of a piotornask-photoresist technology developed for fabrication of multiple-layer thin-film superconductive circuitry. The uehicle selected for this evaluation was a 120-bil associative data processor requiring a set of nine photomasks to define a similar number of patterned material layers of lead, tin, and polymer insulation. A total circuit area of 4 sq in. involved 2500 actitle and 12,000 passive crossings. Several short-free, electrically continuous specimens were satisfactorily completed under this program. Problems encountered in the preparation and use of the requi-ed set of Photomasks are discussed, as also are the problets of providing suitable external connections. A major retarding factor in the development of the superconducting thin-film cryotron technology for many years was the absence of batch fabrication means yielding necessary device density and count per substrate for practical applications. Early workers in the field desired only limited numbers of devices to permit careful study of discrete devices and representative circuitry integrating logic and memory capabilities. For these purposes mask stencils could be formed to selectively control the placement of materials, sequentially vapor-deposited in vacuum, to form the multilayer structure. In general a distinct pattern was required for each material layer; therefore, mechanical provisions were required to change not only the material source, but the patterning mask as well, before each deposition. All deposition steps were preferably performed in a single evacuation of the deposition chamber. Thus the means for storing, transporting, and registering masks and sources with respect to the substrate existed and were operated within the vacuum environment. In the authors' experience, the approach was and remains serviceable for preliminary device study, but was not extensible to an economical manufacturing method by virtue of the difficulties inherent in mask stencil preparation and use, and the capital investment implicit in the mechanization requirements. Since the commercial attraction of the cryotron technology stems principally from its potential for economical batch fabrication, the authors' program has placed major emphasis on fabrication methods. A highly useful method has evolved through adaptation

Jan 1, 1967

By G. J. Saulnier, K. E. Goddard

The US Geological Survey has developed mathematical modeling techniques to assess potential impacts on the hydrologic system resulting from mining of coal and oil shale in northwestern Colorado. Potential impacts of oil shale mining on groundwater hydrology have been simulated using a quasi-three-dimensional, finite-difference model. The model has been used to simulate hypothetical mine dewatering operations at two proposed oil shale mines. Dissolved-solids distribution and solute transport were simulated with a three-dimensional, finite-difference model that was used to evaluate the effects of flooding in hypothetical abandoned mines. The potential impacts of coal and oil shale mining on water-sheds were investigated using a digital watershed model. This deterministic physical-process model predicts responses of the hydrologic system to modifications resulting from mining in basins having snow as the major source of runoff and recharge. Potential impacts of coal development on surface water quality were investigated using a river quality assessment model. The models developed by the US Geological Survey have been useful in defining the potential effects of mining in northwestern Colorado. They are an important first step in analyzing the existing data base and in predicting impacts and new data needs. The models may not be totally applicable on the local scale but are very meaningful on the regional level.

Jan 1, 1983

Jan 1, 1933

NEW MEMBERS The following list comprises the names of those persons who became members during the period Dec. 10, 1915 to Jan. 10, 1916. ANDERSON, FRANK BASIL, Min. Engr., Sampler, Copper Queen Cons. Min. Co., Bisbee, Ariz. BAILEY, LEWIS NEWTON, Min. -Engr 4227 St. James Place, Sail Diego, Cal. BELL, JAMES E., Min. Engr., Care Chile Exploration Co., Chuquicamata, Chile, South America. BONILLAS, YGNACIO SAFFORD, Min. Geol., Copper Queen Cons. Min. Co., Bisbee, Ariz. BRADLEY, GEORGE OLIVER, Mech. Engr Hobart Bldg., San Francisco, Cal. CLARK, GEORGE L., Min. Engr Vipond Mine, Schumacher, Ont., Canada. CONKLING, RICHARD A., Geol., Roxana Petroleum Co. of Oklahoma, Tulsa, Okla. GOHRING, W. B.. Geol., Supt. of Mines, Calumet and Arizona Min. Co., Warren, Ariz.

Jan 2, 1916

By Edward Keller

Jan 1, 1906

By E. H. Tenney

A discussion of the probable future use of coal for power development involves the study of several basic factors, such as future demand for power, the quantity and availability of fuels in direct competition with coal, the price of coal, and a closely related factor—the efficiency and cost of fuel utilization. Predictions based on purely statistical analyses of past coal consumption have definite limitations. For example, statistics showing the relation between coal utilization and total energy consumption from all sources between the years 1890 to 1930 indicate that during that period the energy consumption per person in the United States increased five times, while the coal consumption per person increased only twice1, and there has been an actual decrease in per capita coal consumption since 1920. Figures such as these, compiled by authentic agencies, emphasize the need for caution in attempting estimates as to the future use of coal, and, incidentally, would seem to offer little basis for optimism in the coal industry. They also suggest the value of analyzing broadly the part played in the past by the related factors of power consumption, competitive fuels, coal prices and the efficiency of utilization. Proper weight must also be given in such a study to the present status and limitations of power-plant developments, arid to the question of what the coal industry itself can do to further its own interests arid influence the consumption of its product.

Jan 1, 1936

By E. H. Tenney

A discussion of the probable future use of coal for power development involves the study of several basic factors, such as future demand for power, the quantity and availability of fuels in direct competition with coal, the price of coal, and a closely related factor—the efficiency and cost of fuel utilization. Predictions based on purely statistical analyses of past coal consumption have definite limitations. For example, statistics showing the relation between coal utilization and total energy consumption from all sources between the years 1890 to 1930 indicate that during that period the energy consumption per person in the United States increased five times, while the coal consumption per person increased only twice1, and there has been an actual decrease in per capita coal consumption since 1920. Figures such as these, compiled by authentic agencies, emphasize the need for caution in attempting estimates as to the future use of coal, and, incidentally, would seem to offer little basis for optimism in the coal industry. They also suggest the value of analyzing broadly the part played in the past by the related factors of power consumption, competitive fuels, coal prices and the efficiency of utilization. Proper weight must also be given in such a study to the present status and limitations of power-plant developments, arid to the question of what the coal industry itself can do to further its own interests arid influence the consumption of its product.

Jan 1, 1936

As one surveys the extensive taconite operations on the Mesabi Range, he may find it difficult to believe that only 15 years ago, the iron ore mining industry here was staring at its own imminent demise. Due to the high demands for iron ore during World War II the postwar period of 1946-1950, and the subsequent "police action" in Korea, there was rapid consumption of the Mesabi's already depleted ores, and some economists were giving the Range only 20-25 years of life. In the 13-year period 1941-1953, more than 850 million tons of iron ore were shipped to steel mills, an amount almost equal to the total production during the preceding 30 years. Proven ore reserves dropped from 1.1 billion tons in 1940 to 8.3 million tons in 1954, the largest decrease being recorded in the famed direct shipping ores.

Jan 9, 1968

By Gernot Kostorz

In a recent paper, Raffo and itcheell1 compared solid solution hardening of various bcc alloy single crystals at room temperature and concluded that the expression for localized elastic interaction between dislocations and solute atoms2 that gives the critical resolved shear stress (CRSS) 7,: to = Z . µE3/2 C1/2 where c = concentration, e = misfit parameter, (µ = shear modulus, Z = numerical constant Fig. 1—The slope dT0/dc1/2 for niobium alloy single crystals deformed at 570°K plotted against the misfit parameter € = In' I + 1616 I. from Ref. 6, •estimated from Ref. 7. Table I. Plateau Hardening and Alloy Parameters for Niobium Alloys dT0/dc1/2, kg/mm2 Solute Ref. 6 Tantalum 3.7 ± 0.3 1.9 0.73 + 0.06 9 0.0 ± 0.5 15 Vanadium 16.1 ±1.4 - 0.69 i 0.01 9 -7.4 ± 0.5 16 Tungsten 12.5 ? 1.5 20.9 0.92 i 0.05 10 -5.0 t 0.4 17 Rhenium - 25.9 1.24 11.12 -8.5 ± 0.4 I5 Molybdenum - 14.6 1.04 13,14 -4.6 s†±?˜µ?fF?? 0.5 17 Hafnium - 13.9 0.37 12 4.8 ± 0.5 17 Table 11. Solid Solution Hardening and Alloy Parameters for Tantalum Alloys i)' dTo/dc1/2 kg/mm2, dTp/dc1/2 kg/mm2, Ref. 22 1006 Solute ˜570°K Ref. 7 See Text Ref. 25 Rhenium 44.3 32.5 0.65 -8.5 Tungsten 32.1 24.3 0.34 -4.6 Molybdenum 29.3 19.1 -0.19 -5.9 Niobium 5.8 5.5 -0.43 0.I

Jan 1, 1970

By F. X. Tartaron

F. C. Bond (Consulting Engineer, Processing Machinery Dept., Allis-Chalmers Manufacturing Co., Milwaukee, Wis.) — Papers such as this one which deal in a lucid manner with the obscure fundamentals of comminution theory are always welcome. The author has attempted to bring together several diverse theories and handles them interestingly. However, some of the ideas expressed and conclusions drawn require critical reviewing, for which amenities alone will not suffice. The author points out that the theoretical energy required to break across crystal lattices is of the order of 1000 times the actual energy required to crush or grind, and that this energy in turn is perhaps 1000 times the measured surface energy of the new surface area produced. The energy required to grind commercially is controlled by flaws and dislocations, rather than by the inner strength of the lattice structure. The measured surface energy is only a slight residue left after the face atoms are adjusted to their new environment. The dislocations in the crystal lattice structure, with a spacing of about O.l,u, or

Jan 1, 1962

NEW MEMBERS The following list comprises the names of those persons who became members during the period Nov. 10 to Dec. 10, 1915: BARTH, ERNEST, Petroleum Geol Box 552, Tulsa, Okla. BEROLZHEIMER, D. D.,.Chemist; Librarian, Barrett Mfg. Co., 17 Battery Pl., New York, N. Y. BLIEK, PIERRE FRANCISCO, Mgr., Compania Minera de Oruro, Oruro, Bolivia, So. Amer. BLOCS, JAMES A., Met 1076 1st Ave., Salt Lake City, Utah. BULKLEY, RALPH G., Mine & Mill Supt.; The Montezuma Mines & Mills Co., Montezuma, Colo. BURRAGE, ALBERT CAMERON, JR., Met. Engr.; Director, 85 Ames Bldg., Boston, Mass. CABELL, CHARLES ARNOLD, Vice-Pres Carbon Coal Co., Carbon, W. Va. CHAPMAN, LEWIS CARL, Economic Geol Producer Oil Co., Houston, Tex. CHOFFEL, FLAVIEN AURELIEN, Mgr Ingersoll-Rand Co., Paris, France COY, HARLEY A., Mine Supt American Zinc Co., Mascot, Tenn. DITTMANN, C. 0. ADOLF, Cons. Engr., Beer, Sondheimer & Co., Inc., Santiago, Chile, So. Amer.

Jan 1, 1916

By J. B. Neale

FRom the beginning of its activities, the members of the National Production Committee have felt that the following points were essential to the success of its work: The operators must feel that their operations were not 100 per cent. efficient; that they should be courteous and fair in their treatment of their employees; and that they should set an example of hard work and patriotic interest in increased production. Every move made must appeal to the sense of fairness of all parties concerned. The men must feel that in working more faithfully, and consequently producing more coal, they are rendering a distinct service to their Government in the time of its great need. As the workers feel that greater efficiency on their part results only in greater profits to the operators, the advantage to the operator should be lost sight of, as far as possible, and the advantage to the Government in fighting the war emphasized. Both operators and workers should know that the Government considered increased production an obligation, and opportunity for service, resting on both parties and not on the operators or the workers alone, and that both parties could very much better the efficiency of the pre-war period. Had the committee intimated that it thought the coal shortage was due entirely to the idleness and inefficiency of the workers, its campaign would have failed, for the men would have resented the charge because only too frequently their efforts to produce more coal were thwarted by bad management; besides, the operators would have lacked stimulus to better effort. On the other hand, had the impression been given that the committee thought that the coal shortage was due entirely to bad management, the operators would have resented the charge because only too frequently their efforts to produce more coal were thwarted by the idleness and inefficiency of the workers; and the workers, having been thus indirectly pronounced 100 per cent. efficient and patriotic, would have lacked stimulus to better effort.

Jan 1, 1920