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By L. C. Graton

I. INTRODUCTION. The Relations of Scale in Geologic Work. MANY features of human accomplishment rest upon the possibility of representing natural objects on a scale of different magnitude from the actual one. Most drawings, for example, are of very different scale from that of the object depicted, and indeed are useful mainly on this account. More important than the question of mere convenience, however, is that of meeting the physical limitations of vision.1 Thus, a mural

Jan 5, 1913

By Chas. A. Ashburner

The occurrence of oil- and gas-springs in the State of New York has been a fact of historical record since 1627, when the existence of the Cuba oil-spring was first recorded. The utilization of natural gas at Fredonia in 1821 attracted the attention of the public to the possibility of obtaining an illuminating gas by digging and drilling into the rocks. No active search was made, however, for oil or gas by the drilling of wells until after the discovery of commercial oil in Pennsylvania in 1859. In 1862 a well was drilled at Bradford, McKean County, Pennsylvania, but a few miles south of the New York state line, to the depth of 200 feet, in search of the oil-sand which had been found at Titusville, Oil City, and at other points in Western Pennsylvania. Immediately subsequent to this, other wells were drilled in search

Jan 1, 1888

By R. T. Hukki

IT is no great exaggeration to say that present grinding practice and economics are largely determined by lining design. A record of outstanding liner wear can be achieved with any liner surface pattern that will positively lock the outer layer or layers of grinding media. With no slippage, lining wear is bound to be slight. At the same time, popular practice calls for tumbling loads of about 50 pct of mill volume to obtain maximum grinding capacity. Innumerable parallel grinding investigations have verified that optimum speed for such a mill lies within 70 to 85 pct of theoretical critical speed. If the mill is speeded up to 100 pct of critical, little or no grinding can be accomplished. Earlier Work on Supercritical Grinding: First investigations concerning grinding at supercritical speeds seem to be very old. Remarkable work on the subject has been performed by White,&apos; and his experiments have been described and summarized by Richards.&apos; White&apos;s contributions seem to have passed unnoticed by Fahrenwald,2,3 whose extensive experiments have been well presented, yet apparently very little appreciated. Additional work on grinding at supercritical speed has been reported, e.g., by Lewenson and Tscherny,&apos; USSR; Anselm and Grunder,&apos;, Germany: and Rose and Evans." Great Britain. Subcritical and Supercritical Speeds: In the formula of the critical speed given in the textbooks of mineral dressing, no factor indicating the coefficient of friction is generally included. If this factor = 1.0, which is equivalent to grinding conditions in a mill provided with heavily ribbed lining, the formula of the critical speed holds as such and grinding is possible at subcritical speeds only. In a mill equipped with a smooth or relatively smooth lining, the numerical value of the friction factor in the denominator of the formula becomes <1.0, indicating that grinding at supercritical speeds should be possible in such mills. It has been recently shown by the author&apos; that a wide supercritical speed range will become available for grinding—and especially for fine grinding—if the basic conditions within the mill have been selected properly. Mathematical analysis of mill dynamics at supercritical speeds&apos; has indicated that the mill speed may be increased if: 1) total mass of grinding medium decreases, 2) mass of the individual grinding piece increases, and 3) the coefficient of friction between the outer layer of medium and the mill lining decreases. It is obvious that the mass of the individual grinding piece will be affected by its shape and by its specific gravity. The coefficient of friction decreases with: 1) increasing smoothness of liner surface, 2) increasing roundness of the grinding piece, 3) increasing fineness of material to be ground, 4) decreasing pulp density, and 5) decreasing hardness (abrasiveness) of the mineral to be ground. In a mill equipped with heavily ribbed lining, practically no size reduction will take place between the lining and the outer layer of tumbling medium, because slippage is prevented. In the overwhelming majority of today&apos;s mills the grinding accomplished is by virtue of cataracting and/or cascading media with some action within the tumbling charge. Sub-critical speeds only can be applied. In grate-type or peripheral discharge mills equipped with a smooth lining a tumbling load of any kind of common medium occupying about 50 pct of mill volume will behave in such a way that practically no slippage will take place. This has been verified in experiments run by the author in the laboratory and in pilot plant mills&apos; equipped with smooth lining. Again, the operation is limited to the subcritical range. In a mill with a smooth lining, grinding will be possible either at subcritical speeds or within a wide supercritical speed range as soon as the basic requirements for a desired speed are fulfilled. In a mill operated at supercritical speed, any point on the liner surface proceeds at a speed greater than that indicated by the formula of the critical speed, while any grinding piece situated in the outer layer of the medium against the lining proceeds in the same direction at a speed less than that indicated by the critical speed. This speed difference produces a very effective attrition grinding zone between the liner surface and the outer layer of the medium. The share of attrition grinding of the total grinding accomplished increases rapidly with increasing speed in the supercritical speed range. The smooth surface of the mill lining may be well illustrated by the surface of a bucking board. The outer ball layer may be similarly represented by the lower surface of a muller. If the bucking board, the material to be ground, and the muller all proceed in the same direction at the same speed, no grinding will result. This is the general situation in the mills of today. If, however, the muller is pulled with respect to the board, moving or stationary, grinding will be accomplished effectively. Although grinding in today&apos;s mills is primarily the result of cataracting and/or cascading media, the principal place of grinding at high supercritical speeds will be the attrition zone.&apos; In the mineral dressing laboratory of the State Institute for Technical Research. Helsinki, Finland, large quantities of different ores have been ground in a pilot plant ball mill (3x3 ft) at a top speed about 230 pct of the critical. With the same mill, theoretical investigations concerning the grinding characteristics of ball mills equipped with a smooth lining have been carried out up to the speed of 313 pct&apos; of the critical. With a smaller mill, the grinding characteristics with a variety of grinding media have been investigated at speeds up to 2000 pct of the

Jan 1, 1959

[NORTH AMERICA UNITED STATES ALABAMA ADAMSVILLE U. S. Steel Corp. Neason, James E. ALBERTVILLE Thompson Floral Co. Loudermilk, E. L. ANNISTON No Data Supplied Bonnichsen, Bill BESSEMER U. S. Steel Corp.-TCI Div. Beck, Adolph W., Jr. Boyle, James R. Cofield, William H. *Evans, James D. F., II *Guyton, Jesse C. Johnson, Leland H. Tetley, Albert L. No Data Supplied Crockard, F. H. Fisher, Joe T. Griffin, Joseph M. McFarland, E. A. Mohr, Henry E. Neal, George M. Walker, Wilber D.]

Jan 1, 1961

By James Boyd

In critical times such as the present, when the whole world is agitated by the aftermath of war and the road to peace is blocked by seemingly insurmountable obstacles, it is fitting that we should pause to take inventory of the material resources essential to our national security. Our status as a world power, in peace as well as in war, is intrinsically bound to the availability of minerals, for the foundation of our industrial and economic structurewhich in turn largely determines our military potential and our limits of national prosperity-rests on our ready access to economic sources of iron, copper, lead, zinc, manganese, bauxite, and at least threescore of other metals, minerals, and mineral fuels. By applying the well-known facts of mineral resources to recognized fundamental concepts of preparedness, we can obtain a- clearer picture of the essential needs of our country. Historically, the lure of minerals and other raw material resources has all too frequently led nations to policies of imperialism and war. For more than a century the staking of colonial territory for new sources of raw materials has been a primary objective of many nations. These national policies. of aggrandizement were accelerated by increasing industrialization. The nations, in their aggressive search for

Jan 1, 1948

By Frederick A. Mumpton

For more than 200 years zeolites have been familiar minerals to geologists and mining engineers as minor, but ubiquitous constituents in vugs and fractures of most basalt and traprock formations. More than 35 different species have been recognized including several, such as chabazite, erionite, mordenite, and faujasite, whose adsorption properties rival those of many synthetic molecular sieves. Igneous occurrences of this type have never been mined on a commercial scale; they are generally small and low grade, and they commonly contain as many as four zeolite minerals, along with small quantities of calcite, quartz, and other silicate minerals. Their economic beneficiation to monomineralic zeolite products has also not been achieved and, for the most part, industrial applications of zeolites have relied primarily on synthetic molecular sieves that were crystallized from hydrous aluminosilicate gels. During the middle 1950s, when Union Carbide Corp. and other groups were developing processes and markets for their fledgling synthetic zeolite businesses, natural zeolites

Jan 1, 1975

By Charles E. Barker

Jan 1, 1985

By W. Gundaker, F. C. Schwerer

Natural chromium-bearing spinels (chromites), which are used as refractory materials in basic steelmaking, are the only commercially important chromium ore and are also encountered as difficult-to-separate contaminants in ore deposits of potential economic value. Techniques for characterization and separation of ore materials frequently are dependent on the magnetic properties of the constituent minerals. An experimental program was initiated to explore the effects of temperature and of simple mechanical and thermal treatments on the static magnetic properties of several ore-grade natural chromites. Studies of the temperature dependence of the magnetic properties showed that the natural chromites, which are dilute in the magnetic ions Fe and Cr, order magnetically only at cryogenic temperatures. However, mechanical treatment in the form of crushing produces a magnetic component that is ordered at room temperature and that is of sufficient strength to alter magnetic-separation characteristics. The additional magnetic component apparently is associated with surface structures which develop during crushing and disappear after heating to above about 500°C. Preliminary studies indicate that this surface structure enhances the susceptibility of the chromite grain surfaces to gas reactions at moderate temperatures.

Jan 1, 1976

By H. C. Brown

SINCE 1934 the steel industry has been utilizing the spectrograph for supplementing wet chemical analysis in the production control of electric and open hearth furnaces. This means of control made great strides during the war years because of the general acceptance of the spectrograph and the increased emphasis that was placed on rapid control methods. However, in the post war era, with the demand still on increased production, it became apparent that a still more rapid and economical means of production control was needed. Since the spectrograph had been used mostly in the analysis of low alloying and residual elements, it also became apparent that equipment was needed to extend the spectrographic technique to the analysis of the high alloying elements in stainless steel. For these reasons, companies manufacturing spectrographic equipment were prompted to start development work on direct reading instruments. In June 1949, the Applied Research Laboratories of Glendale, Calif., announced that a direct method of spectrochemical analysis for stainless type steels had been developed. This paper will describe the use of the Applied Research Laboratories Production Control Quantometer in the quantitative control of stainless, silicon, and plain carbon steels being made at the Butler Pennsylvania Div. of the Armco Steel Corp. The Armco Butler Div. has one 70-ton electric furnace and six 150-ton open hearth furnaces. The electric furnace is employed in the making of all types of stainless steel and the open hearth furnaces are used for the production of silicon, wheel, and plain carbon steels. The ARL quantometer was purchased primarily for the purpose of controlling the steelmaking in the electric furnace, but its use has been extended for the analysis of final tests (ladle tests) on a number of different types of stainless, silicon, and plain carbon steels. Because of this additional work by the quantometer, substantial savings in manpower and time have been realized by the laboratory. In the analysis of a set of preliminary tests from the stainless steel furnace, approximately 40 min in laboratory time are saved due to quantometric analyses. Despite the fact that more specialty grades of stainless steel are being made in the electric furnace, the average tons per hour have been increased since the quantometer was put into operation. Specialty grades require more furnace time than regular commodity grades of stainless steel. The installation of the ARL production control quantometer was completed on March 13, 1952. By May 1, 1952, the instrument was calibrated for nickel, chromium, manganese, silicon, and molybdenum, which are the elements necessary for the production control of the stainless steel furnace. Within the following month, training of personnel on the quantometer was achieved and a study of the accuracy of the instrument showed that the results obtained were sufficiently accurate for control purposes. Therefore, on June 11, 1952, the quantometer was placed on production control for all types of stainless steels. Starting September 11, 1952, the instrument was gradually placed on ladle analysis (final tests) as the analytical curves were refined and additional curves were drawn. The quantometer has been relatively free of breakdowns since placing it on production control. The samples from only one stainless steel heat have had to be analyzed by wet chemistry because of instrument trouble. The previously existing heat-time record was also bettered by 15 min on a commodity grade of 18-8 stainless steel. Scope of Control In general, the quantometer determines all elements necessary for the production control of all types of stainless steel heats and for the ladle analysis of various types of stainless steel heats. It is also used in reporting final results for silicon, manganese, chromium, nickel, molybdenum, tin, copper, and aluminum on all silicon steel grades and manganese, chromium, nickel, molybdenum, tin, and copper on several plain carbon steel grades. Table I shows the elements and the concentration ranges of these elements in the various types of stainless, silicon, and plain carbon steel that are determined on the quantometer. A study of the results obtained on ladle test samples of stainless steel types 410, 430, 430 Ti, 446, 301, 302, 304, 304L, 305, and 17-7 PH will be discussed. Also included in the study are the results obtained on ladle test samples of a number of silicon steels. Apparatus In order to take full advantage of the potentials of the production control quantometer, the unit has been placed in an air-conditioned room with relative humidity control. The temperature is maintained at 73&apos;22°F and the humidity at 45&5 pct. The air conditioning serves as a precaution to minimize the amount of adjustment and calibration needed during operation. It also reduces contaminating fumes and dust and thereby lessens the necessity for maintenance on the equipment. The quantometer is composed of three units: the high precision multisource unit, the 1.5 meter vertical spectrometer, and the console. The source unit supplies excitation conditions varying from spark-like discharges to arc-like discharges. The voltage to the source unit is supplied by a motor-generator

Jan 1, 1955

Jan 1, 1911

By C. M. Haight

The mines of the New Jersey Zinc Co. in New Jersey, are situated in the northern part of Sussex County, at Franklin, formerly Franklin Furnace, and also at Ogdensburg. The mine at Ogdensburg is still in the development stage, but the, mine at Franklin, with which this paper deals chiefly, has been a steady producer of high-grade zinc ores for many years. The town is about 50 miles from New York City, among the foothills -of the Kittatinny Mountains. It is equipped with water supply (filtered and chemically treated), good roads, electric lights, efficient police protection and excellent schools, including a new vocational high school. For a mining community, the conditions and location are far above the average. Franklin Furnace Folio, No. 161 of the U. S. Geological Survey, describes the geology and mineralogy of the district in detail, so that merely an, outline of the main characteristics of the orebody need be given. The

Jan 10, 1917

By H. [Eyring], B. J. Zwolinski

[ ] The authors are to be commended for their excellent work on the activities of components in the solid state. It is, however, felt that certain points require clarification with reference to diffusion in the solid state. It is a well established point that any rate process in a non-ideal system can be expressed by the general equation [ ] where ko is the specific rate in an ideal system, and ?A, ?B ... , the activity coefficients of the reactants and ?± and ?M,?N the activity coefficient of the activated complex and the intermediates, respectively. With reference to diffusion, the following simplified treatment in correcting for non-ideality is proposed. The same free energy change is involved in moving a particle from a solution of one activity to a solution of another activity,

Jan 1, 1947

By Richard McCaffery

WHEN we began the study of blast furnace slags we limited our work at first to a study of those slags containing only lime, alumina and silica. On our paper1 on some of the results of this first work, the solubility of sulfur in slags containing no magnesia was reported and the question of sulfur solubility and slag viscosity discussed. There has been, for a long time, a very great difference of opinion among metallurgists as to he effect of magnesia in blast furnace slags, and the literature is full if expressions of the most contrary opinions on the subject. As a result, our next publication&apos; developed the constitution of slags considered as a four-component system, silica-alumina-lime-magnesia, and advanced an explanation of slag structure which accorded with the facts and with scientific theory. The present paper continues our study of the general subject of slags. As blast furnace slags are included in the silica-alumina-lime-magnesia system, which is a particular case of four-component solutions, we have determined that there are 22 components Table 1), which may enter into the silica-alumina-lime-magnesia system and that 10 or 12 of these components may be present in blast furnace slags which are within the ordinary ranges of composition. To cave a very definite conception of the behavior of these components in a slag, we have developed the theory of the cooling of a four-component solution from the liquid state to the solid and the conclusions that we obtained have been made use of in this paper. On account of the importance of the four oxides and 18 compounds which enter into the silica-alumina-lime-magnesia system, some method of calculating the percentages of the various compounds that are present in the slag when the percentages of the oxides are given, seemed very desirable and we develop L method later herein for doing this, and finally we give illustrations of the composition of a wide series of blast furnace slags and show some applications of these composition data.

Jan 1, 1927

NEW MEMBERS The following list comprises the names of those persons who became members during the period Nov. 10, 1916 to Dec.10, 1916. BARNSDALL, THEODORE N., Treas. & Mgr., Highland Gas Co., 24 West Corydon. St., Bradford, Pa. BEASLEY, FRED E., Asst. Supt., Copper Refinery, Consolidated Mining & Smelting Co., Trail, B. C., Canada., BREWSTER, THOMAS T., Vice Pres., Gen. Mgr., Mt. Olive & Staunton Coal CO., 1012 Federal Reserve Bldg.,-St. Louis, Mo. BRINDLE ARTHUR ST. C.... Mining Recorder&apos;s Office, Trout Lake, B. C., Canada. BULLOCK, Harry E., Pres Kentucky-Jewel Coal Co., Lothair, Ky. BUTLER, PERCY BENNETT, Mine Operator :..P. 0. Box 335, Joplin, Mo. BUTLER, ROBERT S Supt., Three Johns Mining CO., ,Joplin,.Mo. CABOT, Godfrey, L., Carbon Black Maker, Gas Engr., 940 Old South Building Boston Mass.

Jan 1, 1917

NEW MEMBERS The following list comprises the names of those persons who became members during the period Aug. 1, 1916, to Sept. 10, 1916: ALLEN, Louis M., JR., Chief Mine Sampler, Old Dominion Min: & Smelt. Co., Globe, Ariz. ATKINSON, CHESTER, Min. Engr., Asst. Supt., Smelt. Dept., Cerro de Pasco Mining Co., La Fundicion, Peru, South America. BAKER, CLAIR LINCOLN, Genl. Mgr., Mexican Dept., Amer. Smelt. & Ref. Co., 1108 Mills Bldg., El Paso, Tex. BARROWS, WALTER A., 3d, Asst. Supt., Blast Furnaces, Thomas Iron Co., Hellertown, Pa. BARTHOLOMEW, GEORGE POMEROY, Asst. Cons. Engr., Guggenheim Bros., 120 Broadway, New York, N. Y. BILLOW, ELMER E., Pres., National Supply Co., 416 NN-rest Grand Ave., Chicago, 111. BROWN, SAMUEL ROLLINS, Mill Supt., The Plymouth Cons. Gold Mines, Ltd., Plymouth, Cal.

Jan 10, 1916

Abrahamson. Guy C., (S&apos;43) Univ. of California, Berkeley. Calif. &apos; Abrego, Alfredo, (S&apos;43) Texas College of Mines Metallurgy, El Paso, Texas. Adamec, Lew, (S&apos;42) c/o Braden Copper Co., Ran¬cagua, Chile. Adams, Charles E., (S&apos;42) Box 1527, Stockton, Calif. Adams, John W? (S&apos;42) Asst. Petr. Engr., Vander¬ bilt Dist., Magnolia Pets. Co., Edna. Texas. Adams, Karl S., (S&apos;43) Univ. of New Ha mpshire, Durham; N. H. Adamson, Charles R., (S&apos;41) Univ. of Utah, Salt Lake City, Utah. Aguilar, Ruperto G., (S&apos;43) Texas College of Mines, El Paso,. Texas. Almone, Francis M., (S&apos;41) Univ. of Toronto, Toronto, Ont., Canada. Ainge, Ronald Farra, (S&apos;43) Otago University, Dunedin, New Zealand. Akarun, Cevdet A., (S&apos;44) Pennsylvania State College, State College. Pa.

Jan 1, 1944

By E. S. Vargas, T. W. Chapman, Samuel W-S Tse

Models for interphase mass transfer rates in the solvent extraction of metals are developed for zinc and copper chlorides being extracted by trilsooctylamine and for copper extraction by LIX 64N from ammonia solution. The approach is to adopt a stagnant film model on which film thicknesses are known and to derive the interfacial metal fluxes for the case where all reversible reactions are fast and locally equilibrated. A growing drop mass transfer cell is used to measure extraction rates. It is found that for the cases studied the transfer rates are mass-transfer limited On the other hand, copper extraction by LIX from acidic solution exhibits slow reaction kinetics, and earlier kinetics models are confirmed. Interactions that cause varying selectivity in the simultaneous extraction of copper and zinc chlorides are demonstrated.

Jan 1, 1981

By J. P. Carson

(Read at the Wilkes-Barre Meeting, May, 1877.) THE works of the Tula Iron Company are in the Republic of Mexico, State of Jalisco, twenty-eight leagues southwest of Guadal¬ajara, ten leagues northwest of the town of Sayula, through which passes the projected line of the Mexican National Railroad. Its geographical position would be about: latitude, 20° 10&apos; N., longi¬tude, 4° 35&apos; W. of Mexico City. The surrounding country is a roll¬ing plateau, 6000 feet above the sea, enjoying the most magnificent climate in the world, the average temperature being about 70°. The works were commenced in 1850 by a company with very small capital, having not the least idea of the undertaking. They soon fell into the hands of the money-lenders, and after changing

Jan 1, 1878

By A. H. Tousley, L. H. Gee

Until comparatively recently, the gypsum industry has been slow to change, often clinging to old processing methods developed a generation ago. Now, however, a highly competitive market has forced gypsum companies to concentrate on devising methods to reduce material and operating costs and improve product quality. In one such effort, Kaiser Engineers recently designed and constructed two modern gypsum plants for Kaiser Gypsum Co., Inc., incorporating centralized control, automatic sequence starting, mill amperage control of the roller milling systems, automatic calcining in kettles, and rapid mechanical stucco cooling. Fig. 1 shows the control panel for the calcining departments at wallboard plants located in Jacksonville, Fla., and Delanco, N. J. In each instance the calcining department (commonly known as the "mill") sets the basis for the quality control for the entire gypsum plant.

Jan 12, 1966

CLARENCE M. HAIGHT, Franklin, N., J. (communication to the Secretary*).-In that hart of Mr. Wilson&apos;s paper describing the Gilman cut-and-fill system, a few features do not appear to be fully explained. In what way is the waste used for filling obtained? The text mentions that, if waste is encountered when driving the filling raises, these raises are stopped until the fill is needed; that seems to suggest mining the capping for fill, which might make the backs of the stopes had as the stopes approach the top of the ore. If, on the other hand, the fill is brought to the raises in cars, are the crosscuts that are necessary in ore or waste? Is the cost of this fill included in the stoping costs given?

Jan 5, 1917