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Alfred E. Hunt, Pittsburgh, Pa. (communication to the Secretary): Mr. Blue's statement (page 576) that, " owing to the presence of iron and other impurities, makers of aluminum. assert that native corundum is unsuited for the production of that metal," is somewhat incorrect, at least so far as it may refer to any objection made by the officials of the Pittsburgh Reduction Co. to the Canadian corundums. We recognize corundum as among the richest and purest of the ores of aluminum, and the material furnished from Canada would offer for us the advantage of a supply near to our works for the manufacture of aluminum at Niagara Falls. The real difficulty which we find in the use of corundum for this manufacture is the cost of the raw material as compared with that of native bauxites. In this item we include not only, the price of the corundum as it has been offered to us, but also the expense of grinding it to an impalpable powder, which must be done before it can be used directly in the manufacture of aluminum, and the cost of preliminary chemical treatment for purification—which latter operation, however, is also required for bauxite. I agree with Mr. Blue that the introduction of new and irnproved processes has greatly reduced, during the past ten years, the cost of manufacturing aluminum; but I am inclined to believe that any further improvements, facilitating the use of corundum for this purpose, would apply, in equal or greater degree, to the common clays (silicates of aluminum) which exist in all parts of the world, are more easily mined and handled, and are likely to be always cheaper per unit of aluminum than any corundum.

Jan 1, 1899

By Mark T. Atwood, Franklin B. Carlson, Louis H. Yardumian

The Oil Shale Corp. (TOSCO) is investigating the application of its oil shale retorting technology to coal processing in its 25-tpd retorting pilot plant. Low temperature char, with a high heating value, plus tar and gas have been produced from high moisture content, low heating value, subbituminous coal. The process, which has been named the TOSCOAL process, uses heated ceramic balls to provide the heat for retorting the coal. One ton of as-mined, subbituminous coal produces approximately 1/2 ton of char, 1/2 barrel of tar, and 1600 standard cubic feet (scf) of gas when the retorting is conducted at 970°F. Properties and yields of the products are presented and compared with Fischer assay yields.

Jan 1, 1975

The total estimated production of coal in the United States during the first century and a quarter of mining is shown in Table 20. This is the total of the production of the various states already shown in the various tables, and is believed to be the first statement of this sort made. No such table prepared from limited data can be accurate, but it is the writer's opinion that the totals shown are less than those actually produced. It was thought that this study would enable a reasonably accurate account of the movement of coal down the Ohio and Mississippi Rivers to be written. The searches made have shown that at this time the data do not exist from which such a study can be made, but some of the facts collected may be useful to future students.

Jan 1, 1942

By W. O. Hotchkiss

RECOVERY and profits in the mining business do not go hand in hand. Some part of an orebody can usually be recovered at a lower cost per ton than the whole orebody or a higher proportion of it. Similarly, the total of the profits that may be made from mining an orebody is in itself not a true measure of the value of the business. The yardstick for money value should be present worth, and this is particularly so for purposes of com-parison. A simple example, well within the bounds of practicability, illustrates these points: Assume a mine to have known ore reserves of 4,000,000 tons. The ore is of uniform grade but is so situated that 1,000,000 tons could be mined more cheaply than the remainder. Present operations are on the basis of complete recovery of the ores. Output is 100,000 tons per year at a profit of $1 per ton. It is estimated that the 1,000,000 tons of readily accessible ore could be mined at the same production rate but at a profit of $2 per ton. For an output of 100,000 tons each year at a profit of $1.00 per ton, the mine will have a life of 40 years; will produce $4,000,000 of total profit, and, at Hoskold rates of 8 and 4 per cent, will have a present value of $1,104,690. If only the easy one-quarter of the ore is considered, with an output of 100,000 tons each year, at a profit of $2.00 per ton, that part of the mine will have a life of 10 years, will produce total profits of $2,000,000, and at rates of 8 and 4 per cent will have a present value of $1,224,800. . Under conditions such as these, then, one-quarter of the reserve ore promptly mined is worth some 10 per cent more than the entire reserve would be on an average basis extending over the longer period. Assume further that one-half, or 2,000,000 tons, of the reserves could be promptly mined at the same yearly rate of 100,000 tons at a profit of $1.50 per ton. Then this part of the mine would have a life of 20 years, would produce total profits of $3,000,000, and would have a present value of $1,320,630; approximately 20 per cent greater than for the whole ore-body on an average basis for the longer period.

Jan 1, 1936

By F. W. Jessen

The Mechanism of solution of salt and mixed halites of sodium and potassium is reviewed. The variation in the rate of salt removal under both laminar and turbulent flow conditions is discussed. Many changes are possible in the development of solution cavities whether used for production of salts or for storage of hydrocarbons. The parameters influencing the type and shape of cavity formed with single well or multiple well systems are examined and information presented regarding field application of techniques developed and the means of controlling overall configuration of solution cavities.

Jan 1, 1972

By Sinha D. K.

As the main source of indigineous energy, coal has a big role to play in the development of national economy of India. Nationalization of the coal mining has brought the entire industry under the unit control of the Central Government following which an ambitious plan for increasing the coal production in the next few five year plans has been undertaken. In order to achieve best all round results, economy-mathematical models of Planning the total system, right from the highest to lowest hierarchial levels of decision making, have been proposed through a Global Model which is detailed in Local Models in stages right up to a mine. Optimum obtained by computer solution of the models would provide basis for objective decision making in the fields of selection of optimum plan for developing the industry, the coal fields and the mines with construction and/or reconstruction of mines, capacity optimization of enterprises and mines therein. Different types of Models and the optimization processes are presented.

Jan 1, 1977

By Phillip J. Maddex

The cost of transporting mineral raw materials and products will receive greater attention in the next 10-20 years because raw material sources and markets are changing. Today, shipping costs may equal 20%-80% of the landed or delivered cost of raw materials and products. Companies are learning that total costs are what count to the company and customers. Transportation has historically been priced at "What the traffic would bear" and little real effort has been made to analyze the shippers problem and provide them with effective and low cost transportation. This climate existed in both ocean and rail transport. The shiplines and railroads did not understand the shipper's problems and few shippers understood transportation and how to buy it. Recently more consideration has been given to the advantages between the American Merchant Marine- American Flag and Foreign flag vessels. The discussions held focused on what action is desirable to encourage American flag operations. Based on extensive studies made by both A. E. Gibson, Maritime Administrator and R. J. Blackwell, Deputy Maritime Administrator, the resulting statistics show that the potential for ocean transport is as follows: U. S. Foreign trade is estimated at 620 million long tons annually in the early 1980's. It was 418 million tons in 1968. In 1968 only 6.4% of the U.S. ocean borne trade was carried on American Flag vessels. About 50 million tons of early 1980's trade will go ill container ships. That leaves over 500 million tons to go as bulk or "neo-bulk" cargo.

Jan 1, 1970

By Marcus A. Grossman

THE institute has established this lectureship to honor the memory of a great American metallurgist, one whose fame has continued long after his passing. As one scientist recently stated it," All metallurgical texts gradually become outdated and outmoded, except those of the great Henry Marion Howe." It seems fitting, then, that, once every year, we should review, in his honor, some aspects of the science in which he was such a distinguished leader, and also discuss any new data that may help to clarify our concepts. It is my privilege, for which indeed I express the deepest appreciation to this Institute, to offer for consideration a few thoughts on the toughness and fracture of hardened steels. Before proceeding to the data, I wish to express my great indebtedness to many associates whose stimulating discussions, generous contributions of data and cooperation in experiments are gratefully acknowledged. (But I wish to absolve them of any blame that may arise from the way in which their discussions and data have been used!) First, Dr. Edgar C. Bain, Vice President, Carnegie-Illinois Steel Corporation, whose amiable but merciless criticisms and always constructive and thoughtful suggestions help unfailingly to guard against pitfalls. Then to associates at Gary Steel Works, especially Mr. H. B. Wishart, Mr. W. K. Smith and Mr. V. Elliott, for great assistance in securing data. Also to Col. C. H. Greenall, Director of Laboratories, Frankford Arsenal, and his metallurgical staff, including Messrs. J. K. Desmond, H. Markus, D. F. Armiento, H. Rosenthal and Henry George, for numerous data and illustrations. Further to Dr. J. R. Low and Dr. M. Asimow, for helpful discussions of effects of states of stress during deformation and rupture, to Mr. J. M. Hodge for discussions and data, to the staff of the U. S. Steel Corporation Research Laboratory for advice and data, and to the Metallurgical Staff at Duquesne Steel Works. The individual acknowledgments will also be found under illustrations. Acknowledgment is also due to Mr. S. C. Snyder for incredibly meticulous scrutiny of manuscript. To all of these, grateful thanks.

Jan 1, 1946

By M. Cross

INTRODUCTION The results of the Japanese dissective investigations have [l-4] transformed our understanding of how the blast furnace operates. These studies revealed an internal structure of the furnace burden with five main zones, as illustrated in Figure 1. In the granular zone the charged material retains its structure whereas in the cohesive zone the iron ore particles are at advanced stages of reduction and form a semi-molten mass with a relatively high flow resistance. In the active coke zone molten iron and slag flow through a matrix of loosely packed coke. The raceway is a relatively small void space generated by displacement of coke due to the hot blast momentum, whilst the hearth is packed with coke, slag and molten iron. [ ] It is now well appreciated that furnace control is largely achieved and maintained by using the burden charge distribution to determine the gas glow distribution within the furnace and, hence, the shape and extent of the cohesive zone. In fact, Wakayama et a1 [5] of Nippon Steel Corporation state that optimum furnace operation is synonomous with the formation of a desirable cohesive zone shape, which in turn is almost solely determined by the burden charge distribution and its mechanical properties [6]. Much of the development work on operating furnaces since the dissective investigations has been oriented towards the identification of external furnace measures which reliably predict the shape of the cohesive zone. Currently the most popular measures are top gas temperature, velocity and CO/CO, ratio profiles [5]. More recently pressure distributions as evaluated from a series of wall measurements down the height of the furnace are also being utilised [7] to identify the position and shape of the cohesive zone. A great deal of emphasis has been placed upon achieving a consistent quality in the burden charge materials, establishing a suitable set of operating conditions and only making changes when forced to, ie., the operation for some reason moves outside a desired operating range or the production requirements change. Operational control schemes based upon this philosophy (eg., Kawasaki's GO-STOP system [8]) have been remarkably successful at achieving both high production rates and relatively low fuel costs. Mathematical models have long been used as tools to assist in the analysis of the blast furnace process. Although, the models have been useful in post-operative analysis and for identifying trends, etc., they have not proved reliable for detailed design criteria or as the basis for effective control schemes. Such mathematical models have moved from simple statistical correlation, through overall and stagewise heat-and-mass balance calcu-

Jan 1, 1984

The following communication has just reached the Institute, from the office of the Provincial Geologist, Department of Lands,-Forests and Mines, Ontario, Canada: During the autumn of 1917 gold was discovered in unsurveyed territory south of Lake Abitibi in northeastern Ontario. This area lies about 70 miles almost directly east of the well known Porcupine area. During the coming summer, the Ontario Bureau of Mines is to make a geological survey of this new gold area. Following the custom of Ontario, this area is being divided into townships, 6 miles square. These townships have recently been given the following names in honor of men well known in the mining and geological world. In alphabetical order the names are as follows: Frecheville-Prof. Wm. Frecheville, Professor of Mining in the Royal School of Mines, London; Past President of the Institution of Mining and Metallurgy. Garrison-Mr. F. Lynwood Garrison, Mining Engineer, Philadelphia, Pa. Harker-Dr. Alfred Harker, F. R. S., immediate Past President of the Geological Society of London.

Jan 6, 1918

By M. C. Fuerstenau, R. K. Price, R. D. Wellik, B. M. Wakawa

Median lethal concentrations of pure and commercially available ethyl xanthate, isopropyl xanthate, amyl xanthate, diethyl dithiophosphate, dibutyl dithiophosphate, and isopropyl ethylthionocarbamate for rainbow trout have been established utilizing static bioassays.

Jan 1, 1975

By M. P. Nackowski, Armond H. Beers, W. T. Parry

Three hundred soil samples were collected on a one-mile grid in a 400-square mile area of the Oquirrh Mountains, Utah, including the Bingham-Lark, Ophir, Rush Valley, and Mercur mining districts. The soil samples were analyzed for copper, lead, zinc, silver, molybdenum, manganese, and iron by X-ray fluorescence using arsenic as an internal standard. Anomalies coincide in most cases with the mining districts. However, in the Mercur district no anomalies were detected. Also samples collected one mile from the Bingham mine barely reflect this major producer. No samples were collected within the Bingham mine area.

Jan 1, 1973

By Henry S. Brown, Jean E. Tilden

Pyrite, pyrrhotite, chalcopyrite, and sphalerite from deposits distributed within the Piedmont and Blue Ridge provinces of North Carolina and adjacent areas were examined by atomic absorption spectrophotometry for cobalt, nickel, manganese, lead, tin, chromium, molybdenum, and gold. The ore samples were also examined petrographically. Cobalt and nickel, in general, enter pyrite and pyrrhotite rather than chalcopyrite and sphalerite. Manganese generally enters sphalerite rather than the other phases where an alternative is possible. The presence of tin in sulfide minerals was noted in a group of deposits east of the known occurrences of tin oxide (cassiterite) in the Kings Mountain belt, which may indicate the presence of a more extensive tin belt in the southeastern Piedmont than was previously recognized. Pyrrhotite from a group of four deposits in Jackson and Clay Counties, North Carolina, differs from pyrrhotite from other Ducktown-type deposits in having cobalt/ nickel ratios less than one, finer grain sizes, and colloform texture. These differences suggest that that this group of deposits has had a history different from that of the other Ducktown-type deposits studied. No significant conclusions could be made based on the distribution of lead, chromium, molybdenum, or gold.

Jan 1, 1975

By L. J. Cabri

The calculation of metallurgical balances for precious metals is very dependent on a precise mineralogical understanding of the distribution of each element. Determination whether the precious metals occur as dilute solid solutions in major minerals is not always easy because of the relatively high levels of detection (9200-500 ppm) of the precious metals by the most common methods of in-situ analysis (e.g. electron microprobe). Particle Induced X-ray Emission (PIXE) analysis of sulfides from Izok Lake, N.W.T., Canada and from the Hilton mine, Mount Isa, Australia with a proton beam (proton microprobe) confirms solid solution of Ag in chalcopyrite from both deposits. In addition, chalcopyrite and sphalerite from Izok Lake both contain indium.

Jan 1, 1984

By R. W. Hyde, B. S. Old, S. E. Eaton

INTRODUCTION ONE of the most important problems facing the steel industry at the present time is that of maintaining at a minimum the sulphur content of many grades of steel where sulphur is known to have harmful effects on both quality and yield. The present outlook in this struggle to reduce the amount of sulphur in steel is rather gloomy since the sulphur content of the raw materials available in the United States is gradually rising, with little relief in sight. A flow sheet of sulphur in the steel process is shown in Fig I. The values used here were obtained by averaging coke oven and blast furnace data at No. 5 furnace in Cleveland and are considered typical for high top pressure practice. The sulphur evolved in the blast furnace top gas was obtained by difference and since the amount is relatively small, little significance should be attached to this particular value. From Fig I it is apparent, however, that coals used in the production of metallurgical coke represent by far the largest single source of sulphur in steelmaking. As an indication of the decrease in quality of these coals as regards sulphur content the weighed average annual sulphur analysis of the coals supplied to two different steel plants, since 1925, is plotted in Fig 2.1 The sharp rise since 1940 is strikingly apparent. Another indication of this trend is found in estimates of coking coal reserves. Thus in the case of Pittsburgh seam coals available in Allegheny, Fayette, Greene, Washington, and Westmoreland Counties in Pa. as of Jan. 1937 only 25 pct of the coal reserves would contain less than 1.50 pct sulphur after washing.2,3 Many of these lower sulphur reserves have been seriously depleted in recent years because of accelerated war demands. Still another demonstration of the increasing sulphur content of coals on a country-wide basis is found in a report by the Bureau of Mines4 which shows a steady increase in the sulphur content of coke made in the United States, It should be noted that this increase continues in spite of the wider use of coal washing in recent years. Sulphur occurs in coal in three forms, pyritic (FeS2), organic sulphur, and a small amount of sulphate sulphur (CaSO4), The sulphur is subsequently found in the coke in combination with carbonaceous material of unknown composition and as calcium and iron sulphides: In considering the general problem of sulphur elimination, the Republic Steel Corp. was interested in determining which, if either, of the two major forms of sulphur in coal contributes the greater portion of sulphur to the coke, Since the ratio of pyritic to organic sulphur varies widely in different coals, it was thought that if it could be shown definitely that the major part of the sulphur occurring in coke originates from one of the two major forms of sulphur in the coal, it would then be possible to select with confidence coal which, although high in total sulphur, would yield coke of fairly low sulphur content, Using the new

Jan 1, 1948

By W. R. Johnson

In the spring of 1935 the writers undertook to compare the geomagnetic and direct-current earth-resistivity methods of tracing a concealed dike along its strike. As far as they are aware no such direct test has been attempted.# The area surveyed lies along United States Highway number 15 about one and one-half miles east of Chapel Hill, North Carolina, and northeast of Bolin Creek (Fig, 1). To the south of the highway is the flood plain of Bolin Crook, and to the north is a hill that rises almost to the elevation of Chapel Hill. A diabase dike, which strikes slightly west of north, out-crops in a. gully just south of the highway. Southward it has been covered by alluvium but northward outcrops again on the southeastern slope of the hill north of the highway. South of the highway the country rock is Triassic shale and sandstone, the northern limit of which is slightly north of the road. On the Geological Map of the United States I the pre-Triassic formations are shown as lower Glenarm and assigned a pre-Cambrian age. Since the ago of the Glenarm has been called into question in Pennsylvania 2, the writers prefer not to commit themselves as to the ago of these rocks further than to say that they are definitely pre-Triassic.

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