Search Documents

By AIME AIME

WEST TEXAS, New Mexico and Northern Mexico form one of the most interesting regions in America for geologists and mining men and are full of points of historical and human interest for others. Including as the region does, a representative portion of the high plateau of Mexico, the front range of the Rocky Mountains and the great down-dropping plains of Texas, there is variety as well as interest in the geological and mining problems there to be studied. Gold and silver mining were the pioneer industries and are yet of high rank in importance. Among the papers to be presented at the El Paso meeting of the Institute this month will be two dealing with silver mining and ore treatment at the Shafter mine in Texas, that most un- usual property which has for so many years been the largest mining enterprise in its region. West Texas is now better known for its petroleum and gas, and in another paper will be described the problems involved in uding natural gas for smelting at the well-known El Paso smelter of the American Smelting and Refining Co. In still other papers, presented at the session sponsored by the West Texas Geological Society and cooperating organizations, the general geology of the region, the potash and the sulfur deposits will be de- scribed. At El Paso the refineries of the great com- panics will be available for visits.

Jan 1, 1930

By A. J. Mcintosh

PRICE changes in competing fuels in the last three decades have reflected the changes in the consuming habits of the people of the United States. Prior to World War 11 the importance of fuel oil and fuel gas increased almost constantly while the relative importance of both bituminous and anthracite coal decreased. During this same prewar period coal prices increased to a much greater extent than oil prices. In fact, in many years, oil prices declined and in most cases are now no higher than they were back in 1925-26. During the war natural economic trends were entirely upset because of the tremendous petroleum requirements of the Army and Navy. Under these conditions many industrial plants were converted to the use of coal and the new installations in home heating and industrial plants of all kinds which might have used oil were practically eliminated. Although petroleum prices were rigidly controlled by OPA coal prices increased several times during the war. An over-all statement as to the rela-

Jan 1, 1947

By Earle C. Waite

THE Industrial Minerals Division this year held no individual sessions of its own except the business meeting Tuesday afternoon. One session was held jointly with the Society of Economic Geologists, one with the Milling Methods Committee, and two with the Society of Economic Geologists and the Mining Geology Committee. At all of these meetings the attendance was better than usual and the Tuesday afternoon session, with nearly 400 present, probably set a new record for the Division. Joint sessions seem extremely popular when papers of mutual interest are presented. On Monday afternoon, mica was the predominating subject. The North Carolina mines provided most of the information presented, although the discussion brought out similarities with the New England mines. B. C. Burgess particularly stressed the fact that with the existing curtailment of mica from India it is necessary to get the most mica in the shortest time from the mines in this country. He said that the Colonial Mica Corp. hopes to have 1000 mines operating in the near future. This seems a great number, but when one considers that these mines employ from 3 to 28 men, mostly nearer the low figure, the output of each mine is relatively small. Although the price of mica is from six to ten times the prewar price, the yield of 8 to 150 lb. of mica per ton of raw ore does not provide high returns to the producer.

Jan 1, 1943

By A. Josefsson

The transition temperatures of 0.01 to 0.02 pct carbon steels are shown to be strongly influenced by cooling rate in the a range, quenching from A, causing a very low transition temperature even after strain aging. In a titanium-stabilized steel and in a steel with 0.05 pct C this effect is absent. NORMAL mild structural steels usually show a structure of more or less pure ferrite, as a matrix, in which cementite grains or pearlite are embedded. Of these components, ferrite is by far the most interesting one as far as ductility and brittle (cleavage) fracture are concerned. Obviously, pear-lite and carbide are by no means necessary for a cleavage crack to nucleate and grow in the ferrite, as steels with a very low carbon content (Armco iron with 0.02 pct C) have an impact transition temperature just as high as semikilled steels with 0.26 pct C.1 Although it has been argued that a very embrittling effect is to be expected from cementite, precipitated as continuous films along the ferrite grain boundaries,'. " the micrographic evidence for a direct causal connection between the brittleness and these films does not seem to be very convincing. On the other hand, it has been stated that cementite particles in ferrite are able to stop ferrite cracks.4,5 In any case, the properties of the ferrite itself seem to be of overwhelming importance to the ductility of steels, justifying a thorough study of steels consisting of ferrite of different compositions, but principally free from pearlite, which means a carbon content below 0.02 pct. Such investigations have been carried out using the impact transition temperature as a criterion of the tendency to brittle fracture and have given some rather unexpected results. One result is the profound influence of carbon on the transition temperature of the steel in normalized condition. If the carbon content is reduced from 0.02 to 0.015 pct and below, a nearly discontinuous decrease in transition temperature appears even with high percentages of such elements as phosphorus and nitrogen present. This will be reported elsewhere." The present paper deals with another effect of carbon upon transition

Jan 1, 1955

By B. J. Guarnera

There have been major changes in the makeup and nature of the uranium exploration industry in recent years. Significant price increases precipitated an increase in exploration activity-according to the Department of Energy, exploratory drilling in 1977, by 140 companies, was almost 8 million m (26 million ft). This represents a 37% increase over the prior year's drilling. Projections for 1978 indicate at least 9 million m (30 million ft) of exploratory holes will be drilled in the US. Exploration expenditures in 1979, including land acquisition, drilling, and other costs, were estimated by DOE at over $236 million. Domestic expenditures for 1978 are estimated at over $250 million.

Jan 10, 1978

By Edward W. Parker

THE agreement of September, 1922, between the anthracite operators and the United Mine Workers of America, which followed the 54.5 months strike during the summer of that year, contained the following provision : The parties unite in a recommendation to Congress that legislation be forthwith enacted creating a separate anthracite coal commission with authority to investigate and report promptly on every phase of the industry and the parties hereby ask the President to request the enactment by Congress of the recommended legislation. The continuance of production after Aug. 31, 1923, shall be upon such terms as the parties may agree-upon in the light of the report of the Commission.

Jan 1, 1924

By AIME AIME

WIDESPREAD interest in the better utilization of coal is indicated by the attendance of over seventeen hundred men interested in the pro- cessing and utilization of coal and its by-products, at Pittsburgh, Nov. 15 to 18. The conference was truly international in scope and of a scientific character, and must be considered a real success. There were dele- gates--official and unofficial-from America, Belgium, Canada, Czechoslovakia, France, Germany, Great Britain, Japan, Mexico, and Sweden. Several Federal and 28 State departments had representatives, also many colleges and universities, and many leading industrial and mining corporations throughout the country. A feature of the sessions was that papers were mostly read in full and attentively listened to, although in some cases they were of a technical nature. The proceedings were opened by the president of Carnegie Institute of Technology, Thomas C. Baker, who spoke of the importance of the conference and felt that without foreign cooperation it could not have been held. There was no need to apologize for the movement of Carnegie Institute of Technology in the matter. Coal is commanding attention in every part of the world; so is power; and coal will remain the chief source of power for generations to come. The coal chemist is working with the engineer, and nobody can forecast what developments there will be in fuel technology. This conference may be the turning point of fuel technology in America. The development and application of these new processes may be of great benefit to Pittsburgh.

Jan 1, 1926

E P MATHEWSON, Disttrict 0 NEW YORK, N Y PAST PRESIDENTS EDWIN LUDLOW, District 0 NEW YORK, N Y ARTHUR S DWIGHT, District 0 NEW YORK, N Y FIRST VICE-PRESIDENT J V, W REYNDERS, NEW YORK, N Y TREASURER CHARLES F RAND, NEW YORK, N Y

Jan 1, 1923

By R. S. Dean

T HE theory of hardening by heat treatment was, as usual, the most actively discussed phase of metal working theory and in spite of the fact that it is now ten years since the dispersion theory was proposed by Messrs. Merica, Waltenberg, and Scott, it still retains a dominating influence. It is being increasingly recognized. however, that in its simplest form, that is, the purely mechanical effect of very fine crystallites distributed through a groundmass, it is distinctly in- adequate. To explain the observed facts we are obliged to assume some well-defined intermediate stage between supercooled solid solution and conglomerate, however fine be the particles of the latter. This intermediate has been inferred by Gaylor and Preston to be "the rejection of the atoms of the dissolved metal from the lattice of the solid solution accompanied by the possible formation of molecules."' Perhaps this may well be designated as the formation of supersaturated solid solution. Some very definite evidence of such an inter- mediate stage has been found in the hardening of steel where it appears that the very hard martensite may be considered as a supersaturated solution of carbon in a iron. The X-ray spectrometry of drastically quenched steel shows a tetragonal lattice whose parameter changes by tempering at 100" until it coincides with the cubic lattice of iron.? The same gradual change of the tetragonal to the cubic lattice has been observed by Sekito when esamining layers on increasing depth below the surface of a quenched carbon steel.

Jan 1, 1930

By Robert R. Walden, LeMont West

K ENTUCKY'S first acid-grade fluorspar flotation Kmill, shown in Fig. 1, was placed in operation Aug. 1, 1952, by the Pennsylvania Salt Manufacturing Co. at Mexico, Ky. During 1951 a critical shortage of acid-grade fluorspar developed and it became necessary for the company to produce part of its fluorspar requirements. In 1951 the company purchased the Crider and Lennen metallurgical fluorspar mill and an adjacent stockpile of tailing at Mexico, Ky. The tailing, assaying about 26 pct calcium fluoride, originated from log washer and jig mill concentrators in the area. As the mill did not have a fluorspar dryer or convenient rail facilities, the company leased the Burleson concentrator at Marion, Ky., where these facilities were available. At Marion, Ky., on the Illinois Central Railroad, dry acid-grade fluorspar is transported direct to the company's Calvert City, Ky., hydrofluoric acid plant. The Mexico flotation plant was reconditioned and designed to produce acid-grade fluorspar from the jig tailing stockpile. The new plant flowsheet is shown in Fig. 2. The ore feed, old tailing, which contains 10 pct of waste rock and coarse gravel assaying approximately 8 pct CaF,, is bound together by sticky clay

Jan 1, 1955

By Anthony F. G. Lucas

BORN on Sept. 9, 1855, in the city of Spalato, Dalmatia. Austria, Antonio Francisco Luchich was the son of Francis Stephen Luchich, a prosperous shipbuilder and ship-owner of Lesina. His mother, Johanna Giovanizio, was known to the people of Trieste as a woman of unusual learning and piety. After receiving his high school training in Trieste, Antonio Luchich entered the Polytechnic Institute at Gratz in the year 1875, graduating two years later as an engineer. He then entered the Naval Academy of Fiume and Pola as a Midshipman, receiving his commission as a Lieutenant in 1878. In 1879, then 24, Antonio Luchich obtained a leave of absence from the Austrian Navy and came to Saginaw, Mich., to visit an uncle. He remained in this country and on May 4. 1885 at Norfolk, Va.. he became Anthony Francis Lucas. an American citizen.

Jan 1, 1945

Jan 1, 1963

By AIME AIME

In the present number of Mining and Metallurgy, issued on the fiftieth anniversary of the founding of the Institute, it appears appropriate to chronicle a few of the interesting incidents respecting its early life. We are fortunate in being able to cull the following notes from unpublished manuscripts of Doctor Raymond and Doctor Drinker, than whom no other members could have written with greater exactness and fidelity. THE seventh decade of the 19th century may be said to have marked an. era in the history of the world. Industrially and .commercially it was marked by the wide application and utilization of discoveries already made, which came to their full effect at this period in steamships, railways, telegraph and cable lines; the standardization of parts in machines, from watches to locomotives; the use of 'dynamite, antiseptic surgery, the open-hearth steel process, the compressed-air rock-drill, the electric generator, and the Gatling gun. Through the opening of the Suez canal in 1870 the maritime trade of the world was revolutionized, sailing vessels were supplanted by steamers, while ocean cables and ocean "tramps" brought about far more rapid movement of commerce than had before been experienced. Politically, this period was marked by the sudden birth of the German empire and the beginning of that intensive internal development of the national resources of that empire in preparation for colonial extension and war, the amazing result of which has been made evident by the recent world conflict. In the United States, the significance of this decade was peculiarly important. The re-admission to the union of Virginia, Mississippi, Texas and Georgia in

Jan 1, 1921

By C. E. Shoenfelt

Operations ill Colorado oil fields in 1934 were not quite so extensive as in 1933, but much better results were obtained and one new oil field was discovered. In all, 26 wells were drilled, of which 9 were oil wells, 1 was a gas well, and 16 were dry holes. New oil production totaled 10,220 bbl. and new gas production totaled 33,714,000 cu. ft. This compares with new oil production in 1933 of 1238 bbl. and new gas production of 14,307,000 cu. ft. Dry holes in 1933 totaled 29 as conlpared with 16 in 1934. Oil was discovered in the Hiawatha gas field, Moffat County, in 1934 in the Mountain Fuel Supply Company's No. 4B Wilson, C. NE. NW. of sec. 23, 12N., 100W. This well was completed in a sand in the Wasatch (Tertiary) at 2304 to 2337 ft., after plugging back from 3797 ft. It made 20 bbl. of oil initially. No. 4B Wilson is the first well in the Rocky Mountain region to discover oil in commercial amounts in rocks younger than Cretaceous, and while it is not expected that Hiawatha will develop into an oil field of important proportions, eventually it may produce a considerable amount of oil as the gas pressure declines. The Hiawatha gas field was discovered in 1926, on one of six structures in what is known as the Vermillion Creek gas area. It is a northeast-

Jan 1, 1935

Jan 1, 1969

By H. O. Hofman

With the exception of the exhaustive paper on the Father de Smet mill, by its designer, Mr. A. J. Bowie, Jr. (Bans., x. 87), nothing, so far as the writer is aware, has as yet appeared on the stamp-mills of the Black Hills of Dakota, although they have been steady producers for the last ten years. Within the small area of about 6000 by 1600 feet, $2,271,341.14 was produced in 1887† from rock averaging $4 per ton in free gold. I. The Ores. Character of the Ores.—The gold of the district is found in quartz and pyrites finely distributed through vast bodies of mica- and amphibole-schists, argillites and phyllites, and also impregnating the schists themselves. The " Belt," embracing the section of Lead City, Terraville and Central City, is the only part worked at present. The principal associated mineral is iron pyrites, with some arsenopyrite and chalcopyrite, garnet and asbestos. The ores from open cuts and upper levels are more free-milling. than those from underground workings below water-line. Hence

Jan 1, 1889

By Wayne E. Tuomi

The mining industry is faced with a pressing problem; that is, to develop more efficient methods of extraction, handling and upgrading-techniques that will do the job faster and better than ever before. New techniques require new machines, or applications of new and improved materials that can be used to modify and improve existing machine and equipment designs. The traditional approach has been to increase productivity by increasing equipment size. Prognostication indicates that the trend toward larger equipment sizes and capacities will continue as one answer to the challenge imposed by future increases in mineral demands. But what is the limit on the continued growth of equipment size? Until about 1930, there was a very definite limit-a limit imposed by the strength of the steels and the power plants then available. The equipment engineer had come to an impasse: even though it was easily possible, for instance, to triple the size of a bucket, it had become impractical to correspondingly enlarge the boom, the counterweight, and the power plant.

Jan 3, 1967

By AIME AIME

FOR many years it has been the invariable custom of the Institute, in addition to its annual meeting in February, to hold a technical meeting in the fall in some mining or metallurgical center in the West. As the activities of the Institute have increased, and especially since the absorption 'of the American Institute of Metals, there have for a number of years been two fall meetings. Never before in the history of the Institute have there been three meetings in addition to the annual meeting in February; in 1920, however, three important fall meetings are to be held. The general Institute trip will be made this fall to the Lake Superior iron and copper country. Members will leave Buffalo on August 20 by steamer, visit the copper mines in and about Houghton, the iron mines of the Marquette and Iron Ranges of Michigan and the iron mines of the Mesabi Range in Minnesota, and' return to Buffalo by steamer on September 3. Technical sessions will be held at Houghton, Minneapolis and Duluth. For a long period it was customary for the Institute to visit the Lake Superior country about every seven years. This trip, however, will be the first visit since 1904. The unprecedented development in both copper and iron mining in this section during this period will make this trip of unusual importance. In addition, a notable series of papers will be presented.

Jan 1, 1920

By A. L. Sweetser

Experience has shown how difficult it is to obtain information regarding laboratory-tests in connection with the chlorina-tion-process for the extraction of gold from its ores, and I therefore present the following method, somewhat in detail, for the benefit of those who may desire to pursue research work in this field. The ore chosen was a partly-decomposed porphyry, extremely siliceous and comparatively soft, and of an average value per ton of from $25 to $26 in gold and $0.68 in silver. The chemical analysis gave: Fe,O,, 3.35; FeS, 1.5; MnO,, 0.75; ZuCO,, 4; A1,0,, 3.20; H,O, 0.7 ; SiO, and insol., 83.50 per cent. The ore, first crushed to pass a 5-mesh screen, was coned and quartered until a 45-lb. sample was obtained. Samples for assay and analysis, taken from this lot by means of riffles, were crushed to pass a 100-mesh screen. The original sample was divided into 10-lb. lots, of which one was crushed to pass a 10-mesh screen; another through a 12-; the third through a 20-, and the last through a 30-mesh screen. Because of the production of an excessive quantity of fine material it was deemed inexpedient to crush finer than 30-mesh size—a decision the wisdom of which is proved by the data in Table I., showing the increasing ratio of slimes, in proportion as the ore is crushed finer. In order to determine the percentage of fines in the sizes of mesh selected, a weighed sample of ore was taken from each mesh, and a sample from the 10-mesh lot was passed successively through 20-, 40- and 100-mesh screens, and the percentage remaining on each screen determined. This process was repeated with the 12-, 20- and 30-mesh lots, with the results given in Table I.

Jan 1, 1908