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By William R. Barton

It is generally conceded as axiomatic that the aggregate producer and the average urban resident have mutually incompatible goals. The producer wants to be near his mass market and the average resident wants him as far away as possible. The traditional economic decision to mine local material to avoid transportation costs is increasingly challenged by zoning and planning bodies and by citizens' groups. This conflict generated much written and spoken word and offered opportunity for great flights of rhetoric. The pressure on the producer also has forced re¬appraisal of the need for the classic confrontation with indications that much of the conflict is more apparent than substantive. In New England several factors combine to increase complexity of the siting problem. It is a region of high land values and population density. Due to the proximity of metropolitan areas, even rural communities have experienced a prolif¬eration of environmental groups with concomitant enthusiastic regional planning and critical watch over land use. In New England where there is little public understanding of the necessity for, and the realities of, mineral production a sophisticated approach to aggregate production site location is required.

Jan 1, 1975

By Ben E. Lindsly

PetRoleum engineers generally are familiar with the investigations of Dow and Reistle,1 Beecher and Parkhurst,2 and Dow and Calkin3 relative to the solubility of natural gas in crude oil. Since the publication of the results of those investigations and the work of Mills and Heithecker,4 little additional knowledge on this interesting and important subject has appeared in the petroleum engineering literature. The reports of Beecher and Parkhurst and Dow and Calkin agree substantially. The data from both investigations showed that, under the conditions of the tests, the solubility of natural gas in crude oil increased in direct proportion to the pressure at which the gas was put into solution, and the solubility decreased to a considerable extent with increased temperature. These facts, and others relating to the changes in viscosity, surface tension and specific gravity of the crude caused by the solution of gas in the oil, have been given due consideration in the petroleum industry, and the recognition of these facts has resulted in a great improvement in the technique of producing oil. However, in these first experiments, various grades and types of weathered crude oil were contacted at various pressures up to 500 lb. per sq. in. gage with gases deficient to a considerable degree in the heavier hydrocarbons, as compared with the gas that was originally in solution in the oil in its natural underground reservoir. The amount of dissolved gas that was liberated upon reducing the pressure to 1 atm. was measured. For these reasons, the complete significance of the effect of dissolved gases in crude oil, as it occurs in nature, cannot be determined directly from the data obtained under the conditions of the tests as described.

Jan 1, 1931

By Carl Swartz

FOR many years kettles used in the melting and refining of lead and other nonferrous metals and alloys have been made of cast iron. The logic of this probably lies in the fact that cast iron has been known as a material of construction for vessels of this type much longer than steel, and satisfactory fabrication from it has been more easily accomplished and better understood. As the capacity of lead refineries has increased, it has been only natural to increase the size of kettles. Today kettles of 150 to 250 tons are not uncommon. As the size of the kettles increased and better shapes were designed, the uniformity of material of construction became more important. Records kept over comparatively long periods of time have shown that the length of service of kettles has not been uniform. Many causes contribute to this and the importance of each has not yet been evaluated. Kettle design, kettle setting, method of firing and material of construction have been changed from time to time to obtain better service, but the variation in length of service is still great. A kettle may fail during the first few heats or may last through more than one thousand heats. The purpose of this article is not to present the conclusions of a finished piece of research on kettle manufacture and use, but to present a series of observations made over considerable time in the hope that others will publish data and that all may be correlated into a logical scheme which will result in better service and longer kettle life.

Jan 1, 1931

By A. D. Zunkel, A. H. Larson

Equilibrium arsenic contents of Pb-As alloys in contact with PbO-As2O3 slags containing less than 30 mol pct As2O3, were determined at 650°, 700: and 750 C in an inert at?rzosphere. In this temperature range, the arsenic content of the alloy increased with increasing temperature in the single-phase liquid slag region and decreased with increasing temperature in the two-phase slag region and the single-phase solid-solution slag region. The PbO-As2O3 phase diagram below 22 mol pct As2O3 was determined by thertrzal analysis and by application of a log ?As2O3/?PbO vS log XAs2o3 /x3pbO plot determined from the equilibrium actiuity data. The resulting phase diagram was not well-defined since the eutectic temperature was not detected in the thermal analysis experiments, although a region of terminal solid solubility of As2O3 was found. Results from the phase diagram determination are compared with an existing diagram in the literature. THIS experimental investigation is an extension of a study by the authors1 on the slag-metal equilibria in the systems concerned with commercial lead refining processes such as softening and dross fuming. The first part of this investigation was a study of the slag-metal equilibria in the Pb-PbO-Sb2O3 system. The only experimental work previously done on the Pb-PbO-As2O3 system was by Pelzel2,3 in which the phase diagram for the PbO-As2O3 system was determined below 50 wt pct As2O3 and the equilibrium constant for the reaction 3Pb + As2O3 + 3PbO + 2As was determined as a function of temperature. No slag-metal equilibrium data have been determined. It is due to the scarcity of information regarding the Pb-PbO-As203 system that this work was undertaken. This paper describes the determination of the slag-metal equilibria in the Pb-PbO-As203 system by equilibrating Pb-As alloys with PbO-As2O3 slags in an inert atmosphere, the effect of 1 wt pct additions of bismuth and copper on the slag-metal equilibria, and the PbO-As2O3 phase diagram both by thermal analysis and the use of the slag-metal equilibria data. EXPERIMENTAL Materials. The materials used in this investigation were analytical reagent-grade and assayed as follows: 1) 99.8 pct PbO (0.014 pct insoluble in CHJCOOH, 0.02 pct not precipitated by H2S, 0.1 pct CaO, and 0.08 pct SiO2); 2) 99.95 pct As2O3; 3) 99.99 pct Pb; 4) 99.0 pct As; 5) 99.99 pct Cu; and 6) 99.97 pct Bi. Room-temperature X-ray patterns revealed no detectable impurities in any of these materials. Apparatus for Equilibrium and Thermal-Analysis Determinations. The resistance-heated crucible furnace used in this investigation employed nichrome elements and was mounted so that it could be raised to surround the reaction tube during each experiment and, subsequently, lowered. A schematic diagram of the apparatus is shown in Fig. 1. Each charge was heated in a 3+-in.-OD by 31/2-in.-high 416 stainless-steel crucible placed in a 41/4-in.-1D by 18-in.-long fused-silica reaction tube which was closed at one end. On a shoulder around the crucible was placed a 3: -in.-OD by 12-in.-long open-end fused-silica condenser tube. The open end of the reaction tube was covered by a water-cooled brass cap with ports for 1) admitting an inert atmosphere to the system through a stopcock, 2) introducing a stainless-steel, motor-driven, paddle stirrer into the crucible, 3) evacuating the system with a mechanical vacuum pump, and 4) sampling the melt with Vycor sampling tubes. The brass cap was fitted to the open end of the reaction tube with a silicone gasket and collar clamp. The furnace temperature was controlled by a Barber-Coleman Capacitrol controller and a chromel-alumel thermocouple. Due to the corrosiveness of the melt, the controlling thermocouple also served as the measuring thermocouple. The temperature of the melt was calibrated against the controller temperature and was checked periodically during each test with a Vycor-enclosed calibrated chromel-alumel thermocouple. The temperature measurement and control can be considered accurate to ±3°C. Procedure. The charge placed in the crucible for each experiment consisted of 1000 g of Pb-As alloy and 300 g of PbO-As2O3 slag. The crucible was then placed in the reaction tube, the condenser tube was placed on the shoulder of the crucible, the silicone gasket and brass cap were fitted on the open end of the reaction tube, and the entire system was evacuated and filled with argon ten times. After the last flushing, a positive argon pressure of 1 psig was impressed on the system. The furnace was then raised to sur-

Jan 1, 1968

By H. J. Mutz

THE International Nickel Co. of Canada Ltd. operates five underground mines and an open pit. Four of the mines, the Frood-Stobie, Creighton, Murray, and Garson, are on the south range of the Sudbury Basin, map above, within a radius of 10 miles of the city of Sudbury, Ontario. The fifth mine, the Levack, is on the north range of the Sudbury Basin, 30 miles to the northwest of the city. The open pit is operating on surface ores of the Frood-Stobie orebody.

Jan 1, 1953

By R. R. Goddard

By use of the frequency response method with a radioactive tracer, it was possible to determine fluid dispersion and distribution in a natural consolidated and an unconsolidated medium. Measurements were made in a linear flow system at oleic saturations of 69 per cent in the consolidated medium, and 100 per cent in both media. Dispersion and distribution were obtained by measuring the amplitude attenuation and the phase velocity of sinusoidal waves with a dual monitor apparatus. The gamma ray emissions permitted in situ measurements at any distance along the porous samples. One result of importance was that the effective diffusivity increased as the wave length increased. As a consequence, a dispersion coefficient appropriate for the injection of large slugs might exceed the value measured by use of small slugs. Since flow models based solely on fluid velocity and an effective diffusivity coefficient imply that the diffusivity should be independent of frequency, such representations were not adequate for the data of this study. A comparison was made with a capacitance model of porous media with deadend PVs, but even this model was not completely adequate. By using attenuation and phase velocity data, fluid dispersion can be predicted without postulating a differential equation satisfied by the tracer concentration, thereby eliminating the need of a complicated model to represent dispersion. INTRODUCTION The flow of similar miscible fluids through a porous medium can be fairly adequately described by two parameters: the average fluid velocity and the effective diffusivity.1-3 It has been pointed out recently, however, that significant discrepancies exist between this representation and the experimental data.4-7 An improved agreement can be obtained by introducing additional parameters based on the concept of dead-end pores. The purpose of the present investigation was to find out whether the frequency response method could be used to measure the relevant parameters. The method was used in the following form. A stream of fluid was flowed at a constant rate through a sample of porous material and the concentration of a radioactive tracer in the fluid was varied sinusoidally at a fixed frequency. The effects of flow through a porous medium are a decrease in the amplitude of the concentration wave and an increase in the velocity of the peaks of the waves above the average velocity. Attenuation and phase veIocity of the waves were measured as a function of frequency and fluid velocity. The simple two-parameter model implies that the diffusivity should be independent of frequency. Data reported in this paper show that the diffusivity decreases as the frequency increases. Hence, as shown also by many others, the two-parameter model is not completely adequate. Coats and Smith 5 used two additional parameters in their model: the volume of the dead-end pores and the rate of mass transfer between dead-end pores and the flowing stream. Their capacitance model of a porous medium containing some stagnant fluid, to which transfer occurs by molecular diffusion, did not explain the dispersion results of either the present study or of theirs. Instead, the capacitance effect can be better described as the result of extreme velocity variations within the pores of the medium, with transfer between the velocity zones by convection. EXPERIMENTAL PREPARATION OF POROUS MEDIA Data reported here were obtained with a natural Berea sandstone, and with two packings of 20/25 mesh sand. Pertinent information about these media is listed in Table 1. The sandstone core was first sealed with a non-

Jan 1, 1967

By Joe B. Alford

Founding of the Institute The advance of population and civilization in the U. S. moved through the woodlands of the East, and reached the edge of the great central plains about the middle of the nineteenth century. There the advance paused for almost a generation - ahead were vast reaches of prairie country, uncharted, forbidding, and populated by hostile tribes of the native Indians. The turmoil of the Civil War, and the readjustments following it, further delayed the advance. By about 1870, the Nation was becoming stabilized again, the conflict with the Indians was closing, and the pressure of growth was forcing population to resume its westward movement. In addition to geography, the Nation had another frontier: the development of its immense natural resources. Conditions of the time brought into sharp focus the need for coal, iron, steel, gold, silver, and other minerals. The application of engineering and science was necessary for the production of these minerals and their manufacture into products to meet the needs of a growing nation. The requirements of the time were eloquently expressed in a paper by AIME member Edmund C. Pechin in 1872 : We find, the world over, the most intense activity everywhere displayed in enterprises requiring prodigious quantities of iron. Railways of colossal magnitude are projected. . . . The growing scarcity of timber is compelling the use of iron in buildings; bridges of wonderful size and strength; huge ocean steamships; barges and boats for lake and river traffic; churches; cars, and thousands of minor articles of every shape and size. . . . The time has come when scientific research is to assume its true position - the day of "sheer force and blind stupidity," whose only protection is a high tariff, has gone forever . . . the physicist, the geologist and mineralogist; the chemist, the engineer, are as essential to success as the [blast] furnace itself. . . . There is no merely practical man, no matter how varied may have been his experience, or how long his practice, that will not benefit from the results of scientific investigation. That there is a growing sense of the importance of having thoroughly prepared scientific men in every department of business is evidenced by the institutions [of learning] that are springing up in different quarters, provided with

Jan 1, 1971

THOSE NOT MARKED ARE MEMBERS; MARKED THUS ?ARE ASSOCIATES. HEAVY-FACED TYPE SIGNIFIES HONORARY MEMBERSHIP JUNIOR MEMBERS ARE MARKED ' . THE FIGURES AT THE END OF THE ADDRESS INDICATE THE YEAR OF ELECTION. AARONS, J. BOYD See Honor Roll. '05 ? AARONSON, ALFRED E Pres., Tuloma Oil Co., Unity Bldg., Tulsa, Okla. '18 ABADIE, EMILE R., Min. En r Box 291, Porterville, Tulare Co., Cal. '76 ABBOTT, CLARENCE E., Gen'l Supt., Iron Mines Div., Tenn. Coal, Iron & R. R. Co., 1405 Minnesota Ave., Bessemer, Ala. '04 ABBOTT, Louis BENJAMIN, Chief Engr., Consolidation Coal Co., Elkhorn Div., Jenkins, Ky. '15 ABBOTT, ROBERT R Met. Engr., Peerless Motor Car Co., Cleveland, Ohio. '12 ABE, ASAKA Fujitagumi Taiwan Office, Taipeh, Formosa, Japan. '14 ABBY, HIROSHI Min. & Met. Engr., Mitsubishi Co., Tokyo, Japan. '17 ||ABOUCHAR, S. S., Cia. de Minerales y Metales, S. A., Minas Viejas, Villaldama, N. L., Mexico. '17 ABRAHAMS, A. I 1391 Madison Ave., New York, N. Y. '14 ?ACKER, E. O'C., Met.,128 East Washington Lane, Germantown, Philadelphia, Pa. '86 ? ACKERMAN, ERNEST R., Pres., Lawrence Portland Cement Co., Plainfield, Union Co., N. J. '15 ACOSTA, J. N., Min. Engr., Cons. Engr Hotel Brewster, San Diego, Cal. '15 ADACHI, JINZOO 11 Shiba Park, Shiba-Ku, Tokyo, Japan. '88 ADAMI, CHARLES J., Min. Engr., Gen'l Supt., St. Joseph and Doe Run Lead Companies, Bonne Terre, Mo. '12 ADAMS, ARTHUR K., Min. Geol., Andes Copper Min. Co., Casilla 230, Antofagasta, Chile. '06

Jan 1, 1923

By O. Hoover, M. Herman, V. V. Damiano

The Jetter and borie' teclznique of determining textures using a spherical specimen has been applied to tlze study of compression-rolled beryllium sheet. Snzall spheres the order of 1 mm in diam cut from the beryllium sheet were autotnatically rotated about tz41o axes using the G.E. single-crystal goniometer. Quantitative pole figures were obtained without tke need to apply absorption corrections. Compression-rolled beryllium exhibited peak intensities ,for (0002) planes of positions tilted 10 deg to the rolling plane and a near random distribution of (1010) planes about the nornal to the rolling plane. TECHNIQUES for determining textures of rolled sheet material are amply described in the literature. The techniques are found to be variations of two basic methods. One due to Decker, Asp, and arker, referred to as the transmission method, utilizes a thin-sheet specimen in which the X-ray beam enters the specimen from one side and the intensity of the beam which emerges from the opposite side is measured. The second method due to chulz,3 referred to as the reflection method, utilizes a thick specimen and the intensity of the beam emerging from the same side is measured. The two rotations of the specimen in the beam are designated a and 8. In order to completely determine the texture of sheet material, it is generally necessary to use a combination of the two methods. The calculations involved in correcting the raw X-ray data for absorption effects and the combining of the data obtained by the two methods are very laborious and time consuming. To avoid the intensity corrections which arise as a result of the changing diffraction volume and path length within the sample other methods have been proposed. The Norton method utilizes a cylindrically shaped specimen cut from the sheet material. Since the rods have rotational symmetry, the absorption correction is constant for rotations about the sheet texture. Jetter and Borie' employed a spherical specimen to analyze the fiber texture of extruded aluminum rods. The spheres were rotated rapidly about the fiber axis to include a large number of grains in the X-ray beam and changes in intensity with respect to tilts of the fiber axis were measured. The absorption correction was constant for all angles and was neglected. The Jetter and Borie' technique finds excellent ap- plication to very fine-grained low-absorbing metals in which the entire sphere volume can contribute to the diffraction volume. In the case of low-absorbing metals, however, serious limitations on specimen thickness occur as demonstrated by Braggs due to de-focussing effects. Peak shifts may occur which negate the assumption that integrated intensities are proportional to peak intensities. These limitations in sphere size to the order of 0.5 to 1 mm for beryllium require that the grain size be sufficiently small to include a large enough statistical sample. The present paper describes the application of spherical specimens less than 1 mm in diam to the quantitative determination of pole figures for compression-rolled beryllium sheet having a grain size the order of 10 p. EXPERIMENTAL 1) Specimen Preparation. Two techniques for spark-machining beryllium spheres were tried. One involved the use of a hollow cylinder as a cutting tool. The tool was fed into the rotating cylindrical specimen as shown in Fig. l(a). The hollow cylinder was carefully aligned such that the axis of the cylinder and the axis of the specimen lay in the same plane and were 90 deg to each other. As the hollow cylinder was fed into the rotating cylindrical specimen, a spherical shape was formed as shown in Fig. 1. Alignment was very critical. Slight misalignment resulted in the formation of a barrel-shaped specimen instead of a sphere. A second technique involved the use of a cutting wheel shaped as shown in Fig. 2 with a groove of the desired radius. A section of the sheet specimen was first turned into a cylinder on the left part of the cutting wheel. It was then shifted to the right and a spherical specimen was turned as shown in Fig. 2. The axis of the cylinder lay in the plane of the sheet. Flats corresponding to the rolling plane of the sheet were used to grip the specimen during the machining operation and these served to identify the rolling plane of the sphere. 2) Rotation of Spec=. The spherical specimen is shown mounted on the G.E. single-crystal goniometer in Fig. 3. The knob A of the goniometer shown in Fig. 3 rotates the specimen about the pedestal axis. These angles have been designated as @ angles. The knob B rotates the specimen about an axis perpendicular to the pedestal axis. These angles have been designated as p angles. A device was made to automatically drive the single-crystal goniometer by means of two flexible shafts connected to the A and B knobs as shown in Fig. 3. The motor system was designed to rotate the knob A, thus rotating the specimen through angles of $I while the B knob remained stationary. After one complete

Jan 1, 1967

By J. G. Thompson

THE methods employed for the determination of oxides and oxygen in ferrous materials may be roughly classed in two groups, "wet" methods and "hot" methods, the first group including the iodine, electrolytic, mercuric chloride, hydrochloric acid, nitric acid, and chlorine methods; the second group including the vacuum-fusion and hydrogen-reduction methods. The wet methods depend upon preferential solubility in a selected medium to separate the metallic portion of the sample from the oxygen-containing constituents. Subsequent analysis of the insoluble residue permits the isolation and separate determination of individual oxides and compounds. The hot methods depend upon the reduction of the oxide constituents of the sample by means of carbon or hydrogen at elevated temperatures. With the exception of the recently developed fractional vacuum-fusion method, the hot methods do not identify individual oxides and compounds but yield only a single value represent-ing the sum of the oxygen contents of several or all of the oxide con-stituents present. With such diversity in the principles and. aims of the different groups, it is not surprising that concordance of results by differ-ent methods has usually been difficult to obtain. The present cooperative attempt to define more rigorously than has been possible heretofore the accuracy and limits of usefulness of the vari-ous methods, originated in correspondence between Dr. John Johnston, Director of Research of the United States Steel Corporation, and other interested metallurgists. The plan was, briefly, to submit identical samples to a number of laboratories for analysis by different methods and to collate the results of these analyses. The project was endorsed by the Iron and Steel Division of the American Institute of Mining and Metal-lurgical Engineers at the annual meeting in February, 1933, and has been conducted under the joint sponsorship of the Iron and Steel Division and the National Bureau of Standards. The latter organization undertook

Jan 1, 1936

By H. I. Althulee

The mines operated by the Compañía de Real del Monte y Pachuca, Pachuca, Mexico, are in two districts, the Pachuca, and Real del Monte. The principal area of mineralization is within a rectangle roughly 10 miles from east to west and 6 miles from north to south. It contains a number of veins from 2 to 20 ft. wide, which are exploited by this mining company. The scattered position of the producing mines led to the construction of two mills between 1906 and 1908; the Loreto mill, in Pachuca, averaged 2600 tons daily, and the Guerrero mill, in Real del Monte, milled 1270 tons daily. On Feb. 1, 1929, the management decided to enlarge the Loreto mill to take the combined tonnage of both mills at that time. This economic measure required the centralization of ore delivery, which would also afford a material saving in the cost of ore transport. The centralization would give the company the following advantages over the former system of operation: 1. Beneficiation at a single mill, closer to source of materials and supplies than the abandoned Guerrero mill. The refinery is also in the Loreto patio. 2. Ore delivery to surface at one point (San Juan Pachuca shaft) instead of at four. 3. Elimination of aerial tramways. To show what would be required to effect this centralization, it is necessary to describe the means by which the ore was delivered to the two mills, prior to centralization. The heart of the Real del Monte district is roughly four miles from that of the Pachuca section. The producing mines in these two districts were: Pachuca district: Real del Monte district: Santa Ana mine La Rica group Camelia group Purisima group Santa Margarita mine

Jan 1, 1934

By Richard L. Coleman

Metallurgical testwork to develop a flowsheet is described, beginning with background information required right through to a final process flowsheet. Both laboratory and pilot plant testing are reviewed with emphasis on the former.

Jan 1, 1978

By Robert W. Hunt

(Cleveland meeting, October, 1912.) PERHAPS of all the scientific economic questions which have been claiming the attention of capitalists, metallurgists, manu-facturers, directors of public utilities, and the general public of America, during the last few years, none have been of more importance than the one relating to the wear and safety of steel rails. The discovery of the Bessemer process made possible modern railway development. In that growth, as has generally happened in all progressive movements, ill its department have not remained equally balanced. Iron rails permitted the construction of roadways for the passage of power-driven vehicles. In time the speed and weight of such carriages proved too much for the wearing-qualities of the rails, and the limit of railway capacity seemed to have been reached. Bessemer made his invention, which was soon perfected and developed, especially as related to steel rails, and thereby increased the limit of capacity, acid vastly greater railway progress was, made possible. The Siemens-Martin open-hearth process followed, and was later supplemented by the Thomas-Gilchrist basic improvement. For a time the Bessemer steel rails of commerce Were, more than equal to all that was asked of them, but this did not long continue, as evidenced by the records in our Transactions. Revolutionary changes occurred in the industrial world, and in no part of it more than in steel-rail manufacture. Great and powerful commercial combinations were made, whose financial resources made possible the supplanting of the then most efficient blast-furnaces, steel-works, mid mills, by others of theretofore unimagined capacity. Old traditions and practices of steel-making were wiped away, and, in too many cases, output was apparently the chief aim, with the result that much dissatisfaction with the wear and safety of rails was felt by railway officials, and the general public was concerned as to its safety when traveling. The climatic conditions of the winter

Dec 1, 1912

By T. H. Aldrich

The Aldrich Mining Go. holds under lease from the Illinois Central R. R. Co. about 14,000 acres, in the east half of Township 12, Range 12 W., in Marion county, Alabama, and owns other lands, of which about 1,000 acres adjoin this leased tract, making a total area of about 15,000 acres, all of which is underlain by the coal-seam upon which the company is operating. This seam is nearly horizontal; and a ravine, diagonally crossing the tract, exposes the outcrop on either side for about 2 miles. The territory has been so divided that nearly the whole of it can be worked out by two collieries. The mines at Brilliant were opened in the fall of 1898, and shipments began in the following spring. The original plan was to furnish steam-coal for locomotives to the Illinois Central R. R. Co.; and upon this expectation the investment of capital was made. The field was entirely new; and the softness of the coal at the outcrop induced the belief that it could be very cheaply mined. A contract for the delivery of a large quantity of coal to the railroad was accordingly executed. But with the advance of' the entries to increasing distances from the outcrop, the coal proved so hard that it could no longer be drilled with a breast-auger; and the expense of mining became so great that the contract for cheap steam-coal had to be canceled. It became evident that the work must be done with machinery and explosives, if it could be profitably done at all. On the other hand, the excellent quality of this coal opened, at the same time, a possible market not specially contemplated at the outset—namely, that of a first-rate coal for domestic and general uses. Since no other deposit of such coal was known to exist on the line of the Illinois Central, or any other railroad

Jan 1, 1907

By Raymond B. Ladoo

Wollastonite is a calcium metasilicate, with the formula CaSiO3; containing theoretically 48.3 pct CaO and 51.7 pct Si02. It is one of many natural and synthetic silicates with varying CaO/SiO2 ratios, with and without water of crystallization. While it is a very common mineral, deposits of sufficient size and purity to be of commercial interest are unusual. There is only one producer (1958) of wollastonite for industrial use in the United States, Godfrey L. Cabot, Inc. at Willsboro, New York. There has been a small production of surface material for ornamental use from near Blythe, California. Carload tests have been made on California wollastonite for making mineral wool and a commercial plant for this purpose was projected in 1957. Properties Wollastonite is monoclinic and commonly occurs in masses or aggregates of bladed or needle-like crystals. It has a perfect cleavage parallel to the long prismatic axis. It is rather brittle and some types grind easily to a very finely fibrous product, but other types, due to interlacing of fibers, are tough and difficult to grind. Mobs hardness is 4.5 to 5; specific gravity 2.8-2.9; index of refraction 1.616 to 1.631; melting point 1,512°C. Color when pure is a brilliant white, but when less pure it may be gray or brown. Luster is vitreous, transparent to translucent. Common mineral associates are garnet (several varieties), diopside, calcite and quartz. The nature of the mineral impurities determines to a large degree the commercial value of a deposit. At Willsboro, New York, the impurities consist chiefly of iron garnet and iron diopside which are both magnetic and so are easily removable by magnetic separation, yielding a nearly theoretically pure product. Some deposits in California contain calcite and quartz which cannot be removed cheaply, thus limiting market possibilities. Occurrence Wollastonite is a contact metamorphic mineral occurring in most places within or associated with impure limestones. The deposits at Willsboro, New York1,2,3,5 consist of two or more beds dipping 15-50°E and striking NW-SE. The main bed, 30 to 70 ft thick, may be traced on the surface for at least 2 ½ miles. In this belt, the Pre-Cambrian Grenville limestone has been injected and partially replaced by the more liquid portions of an anorthositic magma. Buddington and Whitcomb3 have described the rock as "Mixed gneisses, pyroxenite and garnetiferous gneisses and skarns." Prospecting revealed the wollastonite at ten different places in the belt, overlain in most places by a garnet rock. Diamond drilling has proven several million tons with probable reserves around 15 million tons. Interbedded with the wollastonite are beds of garnet from a few inches to several feet in thickness. In the wollastonite ore itself the chief and almost only associated minerals are garnet (mostly almandite but some andradite and grossularite) with small amounts of green hedenbergite. Inasmuch as the almandite and diopside are magnetic they are easily separated from the wollastonite in high intensity magnetic separators. If grossularite should occur in quantity other means of separation would be needed. Wollastonite has been reported at 35 localities in California12 but only those in the Big Maria and Little Maria Mountains, 16 to 20 miles north of Blythe, Riverside County, are

Jan 1, 1960

By Jacques B. Wertz

Detailed structural studies in southeast Arizona have successively revealed (1) the local attitudes of individual fractures (with lateral and/or vertical displacements), (2) the patterns exhibited by groups of fractures, and (3) the trends and directions shown by fracture groups or zones on a regional scale. The results of the studies have been twofold: First, domes were locally determined from these fracture arrangements, even where other criteria failed; and, second, fundamental breaks brought out the breadth of the Texas lineament in southeast Arizona as well as major northwest- and northeast-trending fracture zones. Coincidence of one or several domes with the major intersections of fundamental breaks can be centers of important mineralization, as in the instances of Bisbee, Ajo and Morenci. THE OVER-ALL STRUCTURE OF ARIZONA A northwest-southeast trending anticlinorium has been suggested as the structural setting of Arizona. Starting in Triassic and culminating in late Cretaceous times, this deformation resulted from stresses of considerable magnitude with varying ratios of com pres sional and uplifting forces. However, the series of parallel flexures could just as well have been caused by isostatic movements involving dilation under tension with only incidental compression, as later emphasized by dike filling and block faulting (Fig. 1). The anticlinorial deformation, which is also suggested by the fact that the Pre-cambrian rocks to the southwest are all concealed by sediments, could be somewhat reminiscent of the conditions that affected the classical swarm of parallel dikes of wager.' ANALYSlS OF DATA As a first step in this analysis, all structural information obtained on such features as fractures and their relative displacements, faults, dikes, anticlines, synclines, and Precambrian and Laramide-Tertiary intrusives were plotted on maps along with structural trends inferred from aerial photographic mosaics. Next, the faults in southwest Arizona were classified according to time of occurrence and relative importance. The fault assemblages were then examined as to geometric or spatial arrangement and correlated with the occurrences of domes and existing Finally, the conjunction of fracture intersections and domes was analyzed and compared with locations of known ore deposits. Differentiation of Faults According to Time and Relative Importance: The faults encountered were grouped as follows: (1) Basin and Range faults, latest in time; (2) secondary faults; (3) primary faults; and (4) lineaments, earliest in time by inference. BASIN AND RANGE FAULTS- Generally concealed by alluvium, the Basin and Range faults are normal

Jan 1, 1969

By T&apos Ke, ing-sui

Accoriding to the classical theory of elasticity, the elastic portion of the stress-strain curve is represented by a straight line. such a representation implies that there is a linear relationship between strain and stress and also that strain is a single-valued function of stress and vice versa. Actually, such a one-to-one correspondence between strain and stress does not exist in real metals. A well-known example is the elastic after-effect on unloading. Another familiar example is damping or internal friction, that is, the dissipation of energy attending vibration. In an extensive review of such phenomena, zener1,2 has proposed the term "anelasticity" to denote that property of a solid in virtue of which strain is not a unique function of stress in the non-plastic region. The phenomena arising from anelasticity are called anelastic effects. The measurements on anelastic effects are important in many fields of metals technology. The, in precise instruments such as watch springs, difficulties often arise from the slight dimensional changes after fabrication. The internal friction or damping capacity of metals is often an important factor in deciding whether they are appropriate for instruments in which there are accompanying vibrations.3 However, for metal scientists, the study of anelastic effects furnishes a powerful tool for understanding many properties Of meta1s in terms of their microstructures or atomic interactions. In order to utilize the anelastic measurements to their fullest extent for acquiring such information, the experimental studies Of anelasticity must be interpreted by appropriate mathematical analysis. For a great many problems, however, the necessary information often Can be Obtained by general qualitative arguments. From the definition of anelasticity, any physical changes occurring in a specimen as a result Of the applied stress will cause anelastic effects if such physical changes are accompanied by a delayed change of elastic strain. Under these circumstances, we have the condition that strain lags behind the stress. We may mention the stress-induced transportation phenomena as examples. These include the stress-induced thermal diffusion,4-7 the stress-induced diffusion of particles,8-l2 and the stress-induced viscous slip along the microelements in metals.12-15 The differential equations describing the microscopic mechanism in these phenomena lead to relations in which stress is linear with respect to strain (and/or their derivatives). Thus if we Can demonstrate that the superposition principle is valid under the circumstances in which the anelastic effects are observed, we would expect in the macroscopic relation a linear relationship between stress and strain and their derivatives. This report is to describe a number of anelastic effects observed in alpha-iron, and an attempt is made to derive valuable information from a critical study of these

Jan 1, 1949

By T&apos Ke, ing-sui

Accoriding to the classical theory of elasticity, the elastic portion of the stress-strain curve is represented by a straight line. such a representation implies that there is a linear relationship between strain and stress and also that strain is a single-valued function of stress and vice versa. Actually, such a one-to-one correspondence between strain and stress does not exist in real metals. A well-known example is the elastic after-effect on unloading. Another familiar example is damping or internal friction, that is, the dissipation of energy attending vibration. In an extensive review of such phenomena, zener1,2 has proposed the term "anelasticity" to denote that property of a solid in virtue of which strain is not a unique function of stress in the non-plastic region. The phenomena arising from anelasticity are called anelastic effects. The measurements on anelastic effects are important in many fields of metals technology. The, in precise instruments such as watch springs, difficulties often arise from the slight dimensional changes after fabrication. The internal friction or damping capacity of metals is often an important factor in deciding whether they are appropriate for instruments in which there are accompanying vibrations.3 However, for metal scientists, the study of anelastic effects furnishes a powerful tool for understanding many properties Of meta1s in terms of their microstructures or atomic interactions. In order to utilize the anelastic measurements to their fullest extent for acquiring such information, the experimental studies Of anelasticity must be interpreted by appropriate mathematical analysis. For a great many problems, however, the necessary information often Can be Obtained by general qualitative arguments. From the definition of anelasticity, any physical changes occurring in a specimen as a result Of the applied stress will cause anelastic effects if such physical changes are accompanied by a delayed change of elastic strain. Under these circumstances, we have the condition that strain lags behind the stress. We may mention the stress-induced transportation phenomena as examples. These include the stress-induced thermal diffusion,4-7 the stress-induced diffusion of particles,8-l2 and the stress-induced viscous slip along the microelements in metals.12-15 The differential equations describing the microscopic mechanism in these phenomena lead to relations in which stress is linear with respect to strain (and/or their derivatives). Thus if we Can demonstrate that the superposition principle is valid under the circumstances in which the anelastic effects are observed, we would expect in the macroscopic relation a linear relationship between stress and strain and their derivatives. This report is to describe a number of anelastic effects observed in alpha-iron, and an attempt is made to derive valuable information from a critical study of these

Jan 1, 1949

By C. Burton Clark, J. Spotts McDowell

Refractories are defined as "materials having the ability to retain their physical shapes and chemical identities when subjected to high temperatures," or as "nonmetallic materials suitable for the construction or lining of furnaces operated at high temperatures." While resistance to "high" temperatures is thus the primary requirement for refractory materials, it is by no means the sole requirement. They must be able to withstand thermal shock resulting from rapid heating or cooling; other stresses induced by temperature change; pressures from the weights of furnace parts or contents; mechanical wear (abrasion) resulting from movement of furnace contents; and chemical attack by heated solids, liquids, or gases. Refractories of many kinds are needed for the many and widely diversified industrial applications. Those in greatest demand are classified on the basis of composition or properties into a few main groups, known as alumina-silica, silica, basic and insulating refractories. In each of these groups there are several classes. In addition to those included in the main groups, there are various special refractories, including silicon carbide, carbon, zircon, zirconia, alumina, and several others. Alumina-silica refractories comprise two main divisions: fire clay and high-alumina. The alumina content of fire-clay refractories covers the range from about 45 pct to 18 pct, and the silica content from 50 pct to 80 pct. The alumina content of fired high-alumina refractories ranges from about 99 pct to 45 pct, and the silica content from about 0.5 pct to 50 pct. Silica refractories of the different classes contain 94 pct to 97 pct silica. Basic refractories include periclase (magnesite), chrome spinel, forsterite, and dolomite. Refractory materials, including insulating firebrick, are supplied mainly as preformed shapes. Other products include bonding mortars and high temperature cements, ramming mixtures, plastic firebrick, hydraulic setting castables, dead-burned grain magnesite, and dead-burned dolomite. Refractory brick are classified on the basis of their physical form as Standard Sizes and Special Shapes. The Standard Sizes are brick of certain definite sizes and relatively simple design which are used in sufficient amounts to permit quantity production. The brick most widely used are the standard 9 in. X 4 ½ in. X 2 ½in. and 9 in. X 4½in. X 3 in. straights and corresponding series of sizes. All brick of nonstandard dimensions are regarded as "special shapes." They include a wide variety of brick regularly used for specific services, such as baffle tile for boilers, checker brick for regenerators, and others; together with shapes of special design manufactured on particular orders from designs submitted by the user. Not included in the broad classifications of Standard Sizes and Special Shapes are several specific-service refractory products, usually made by companies which specialize in their manufacture, or in some cases by the consumers themselves. These products include

Jan 1, 1960

By Hans Lundberg

FOR the last 20 years, geophysical methods have been in practical use. The results accumulated during this time have been broad enough to enable us to formulate some general rules for conducting geophysical surveys to the best advantage. It is a well established fact that electrical and magnetic methods have aided the geologist to outline bodies of ore, to differentiate between various types of rocks hidden from view and also to determine the thick-ness of the layer of drift that covers the bedrock. Fundamental require-ments for a successful solution of a geophysical problem is the existence of physical differences between the various formations under investiga-tion. If such conditions exist, our problem becomes a physical, mathe-matical and geological analysis of the effects of these differences upon the structure of an arbitrarily produced, or already existing, field of force. Experience has shown that reliable and consistent results in analyzing such fields of force are obtained only if: (1) the methods and apparatus used are scientifically sound and designed to provide information with a maximum amount of accuracy, reliability, sensitivity, simplicity and speed of operation, and (2) the interpretation of the results of such an investigation is guided not only by rigid mathematical rules but also by common sense, based upon sound geological knowledge and imagination. Today, a number of methods are based upon sound principles, are highly sensitive and are well suited for field work. The instrumental developments have resulted in self-contained instruments, which permit the determination of field ratios and intensities with great accuracy. Magnetic surveys have almost become standardized. The electrical methods, mostly based on the determination of potential-drop ratios, or electromagnetic field ratios, are built as bridge circuits and it is easy to determine amplitude, as well as phase relationship of the various electrical and electromagnetic fields.

Jan 1, 1938