Search Documents

By E. S. Greiner

THE hot working of chromium was first reported by Hunter and Jones; who used small pellets of the material obtained by the reduction of chromium chloride with sodium. Later, the working of chromium at 600° to 1100°C was reported by Marden and Rich,2 and at 1250°C by Kroll3 The hot rolled material3 had a Brinell hardness of about 150 (62.5 kg, 2.5 mm ball, 1 min) and was brittle at room temperature. Except for that associated with hardness indentations, no plastic flow in chromium at room temperature has been reported to the author's knowledge. Studies described here have shown slip markings in chromium after deformation at room temperature.

Jan 1, 1951

By Frederick Prime

In this supplementary list no titles to which an * is prefixed have been seen by the compiler; and he will be most thankfu1 to have any omissions or inaccuracies in the list sent to him to be published as a second supplement in the next volume of the Transactions. The author is indebted to Messrs. Robert Clarke, of Cincinnati; Thomas Macfarland, of Towanda; Professor F. W. Simonds, of Chapel Hill; and Professor J. J. Stevenson, of New York, for valuable assistance. Cedar Point IRON Company, Baltimore, July 31st, 1880. Alabama. Geological Survey of Alabama. Report of Progress for 1877 and 1878; by Eugene A. Smith, State Geologist. Montgomery, 1879. 8vo., 139 pp., and 4 maps.

Jan 1, 1880

By D’Arcy A. Shock, J. G. Davis

Continental Oil Co. has spent more than four years of research on the fundamentals of recovery of potash by solution mining. This work included laboratory investigations of salt solution, brine flow, selective extraction of KC1 from sylvinite, and control of cavity geometry. Laboratory results were expanded by means of a series of field tests, and subjects such as well completion and hydraulic fracturing were added to the investigation. Both single-well and multiwell mining systems were studied in the field work. This paper discusses one field test in which potash was solution mined from a thin sylvinite ore zone in the Carlsbad Potash Basin. A two-well mining system was used for this test.

Jan 1, 1970

By Colin Fink

TANTALUM and columbium occur together in tantalite and columbite ores, which may be considered as ferrotantalate (FeTa206), with part of the iron and tantalum replaced by manganese and columbium respectively, the general formula, therefore, becoming (Fe, Mn)O.(Ta, Cb)205. The ratio of tantalum to columbium is not fixed; the amount of tantalum may vary from one-third to three times that of columbium. Minerals having a high content of tantalum are called tantalite, while those possessing larger amounts of columbium are classified as columbite ores. These minerals are found in pegmatites and often occur in veins associated with cassiterite and wolframite, and may contain small amounts of tin, tungsten, titanium and silica.1

Jan 1, 1931

By W. D. Robertson, R. E. Reed-Hill

Slip on (11221 planes, which do not contain a close-packed direction, has been identified on crystals strained at —190°C. Evidence is also presented to show that (1071) pyramidal slip is a mode of deformation at 25ºC in a limited orientation range. PYRAMIDAL slip (l011) <1120> in magnesium at elevated temperatures has been established for some time.1-2 More recently, Burke and Hibbard reported this mode of deformation at 25ºC, but their results were questioned by Craig.&apos; Also, as far as the present authors know, slip in magnesium on pyramidal planes of the second order, Type II (1122)) has not previously been reported, although Gilman"," identified (1122) slip in another hexagonal metal

Jan 1, 1959

By W. A. Backofen, M. L. Ebner, D. H. Avery

Slip on (11221 planes, which do not contain a close-packed direction, has been identified on crystals strained at —190°C. Evidence is also presented to show that (1071) pyramidal slip is a mode of deformation at 25ºC in a limited orientation range. PYRAMIDAL slip (l011) <1120> in magnesium at elevated temperatures has been established for some time.1-2 More recently, Burke and Hibbard reported this mode of deformation at 25"C, but their results were questioned by Craig.&apos; Also, as far as the present authors know, slip in magnesium on pyramidal planes of the second order, Type II (1122)) has not previously been reported, although Gilman"," identified (1122) slip in another hexagonal metal

Jan 1, 1959

By H. M. Callaway

There are key words common to Government and the minerals industry, the use of which immediately spark interest, argument and confusion. Among these is productivity, a term ranking for widespread misunderstanding with mineral self-sufficiency and mineral conservation. Each interpretation of these words tends to emphasize a single aspect and either minimize or ignore the complex dynamic system of things that influence the Nations mineral productiveness. This paper1, abstracted from a monograph on lead now being prepared for publication by the Bureau of Mines, not only sheds light on the trend of productivity in the lead-zinc mining industry but it presents the basis for forming a common general notion of what the term productivity implies.

Jan 11, 1961

By James Yancik

The Howe Coal Co. is mining the Oklahoma Lower Hartshorne bed which ranges in seam thickness from 38 to 42 in. and pitches approximately 7° to the northeast. The raw feed to the cleaning plant averages about 20% ash and 1.10% sulfur, being reduced in the cleaning process to 4.8% ash and 0.9% sulfur with a free swelling index of 8 or 8%. This coal rivals the Pocohantas seam in chemistry and coking characteristics but has better fluidity than the Pocohantas seam coal. The coal is presently being prepared for the Japanese steel market in an 85-tph pilot plant designed and constructed by Roberts & Schaefer. The cleaning-plant flowsheet is discussed in detail.

Jan 1, 1972

By AIME AIME

AT the seventeenth National Metal Congress, held at Chicago, Oct. 1-3, the Iron and Steel Division and Institute of Metals Division participated with the American Society for Metals, American Welding Society, and the Wire Association in one of the most successful meetings ever held. The total attendance at the technical sessions and the scope of and interest shown in the exhibits at the Exposition were greater than at any of the "Metal Weeks" since the depression began. The Iron and Steel Division held two all-day symposia and one general session. The latter, at the International Amphitheatre, Wednesday afternoon, was the only one poorly attended. This was attributable, at least partly, to the location of the meeting roan.

Jan 1, 1935

By R. A. Wyman

KYANITE schists in the Sudbury area have been generally described by Haw,1 who has also given particular information on preliminary treatment of three large samples from Dryden township, Ontario.2 Kyanite, garnet, biotite, quartz, and feldspar comprise the main ingredients of this ore. Kyanite is the valuable mineral. About 5 ½ tons of -35 +200 mesh product, made by dry rod milling, screening, and separation on the Exolon magnetic separator, were available for treatment by flotation. Magnetic separation had effectively reduced garnet and biotite so that flotation feed consisted essentially of kyanite, quartz, and feldspar, the kyanite content averaging 32 pct and representing about 86 pct of the kyanite in the original ore.

Jan 1, 1958

By J. R. Billingsley

The Sunro mine, operated by Cowichan Copper Co. Ltd., under lease from Sunro Mines Ltd., a Cominco subsidiary, is located on the south end of Vancouver Island. Exploration and limited development before 1960 established the existence of twelve mineralized zones. The "B" and "C" orebodies of the River zone contained an estimated 937,000 tons of 1.80r/, copper plus approximately 35 cents per ton of precious metals. On reviewing the indicated tonnage and the exploration possibilities in the River zone and the other eleven zones it was decided to construct a 1500-tpd mill. In August 1961, excavating of chambers for a crushing plant and concentrator located underground near the River zone began.

Jan 12, 1963

By John G. Reid

Subsequent to extensive laboratory testing, a pilot plant was constructed to further evaluate the process for high temperature copper cementation on iron in continuous operation. The plant was designed to produce 1 to 10 tons of copper a day depending on the copper concentration of the pregnant solution. The energy required to operate the plant was very low as virtually all the solution heating requirements were supplied by the exothermic cementation reaction. The results demonstrated that this, process has potential for commercial application with respect to operating considerations, and yields a copper product in excess of 95% copper at high reaction rates, low iron consumption, and at least 98% copper recovery from solution.

Jan 1, 1976

By Bayard Morrow

THE copper-bearing ores concentrated at the Anaconda plant of the Anaconda Copper Mining Co. are principally a mixture of copper and iron sulfides associated in a gangue consisting of quartz, lightly altered granite and feldspars, with sphalerite and galena and more rarely barite and hubnerite as accessory minerals. The predominant sulfide is pyrite. The copper minerals present are: chalcocite, bornite (Erubescite), enargite, chalcopyrite, covellite, tetrahedrite and some tennantite. Normal concentrator practice removes a slime prior to ball-mill grinding. The deslimed ore is ground to approximately 10 per cent plus 65 mesh for flotation. Two selective flotation circuits are used, one for deslimed ore and one for slime. The metallurgical results obtained are shown in Table 1.

Jan 1, 1933

By Jose M. Sobral

Approximate figures for petroleum production in Argentina for 1929 show an increase of only about 300,000 bbl. over production for 1928. This increase is due to greater yield in the Plaza Huincul and in the Salta regions. Table 1 shows the distribution of production in the various fields of the whole country, using estimates for the later months of the year. The outlook for production remains about the same as in 1928. It is believed that in northern Argentina there are regions that contain oil, but they are yet unexplored. Notable traces of oil at depths between 1280 and 1390 m. have appeared in a 1500-m. boring in Comodoro Rivadavia, but their importance is unknown.

Jan 1, 1930

By Richard H. Terhune

Slag and matte, in lead and copper smelting, are, for convenience of removal, tapped into pots of small capacity, usually of paraboloid form, of cast-iron, weighing 275 to 300 pounds, and holding the same weight of slag. As in many smelting districts one ton of ore makes a ton and a quarter of slag, a large number of pots is needed to equip an ordinary plant. Sudden and frequent expansion of the solid bowl causes the pots to crack at the bottom in a few months, and the matte, a very fluid sulpliide, enters these rough fissures and speedily corrodes its way through the vessel. 1 find, from one year of practice with a slag-

Jan 1, 1887

By William R. Hart

I was this morning an interested listener to the remarks of Mr. Ashbel Welch in regard to his designing a new section for steel rails, in 1866; and for the salze of the truth of history, and in order t:, give the credit to an American (and where it rightfully belongs) of higning the first section for steel rails, which was intelligently adapted to that material; I beg to state the following facts: On the 14th of August, 1866, Mr. Ashbel Welch gave me an order for 200 tons of steel rails, to be made bbr the Camden and Amboy Railroad, from a section designed by him. A copy of this section 1 append herewith.

Jan 1, 1881

By Harold R. Bradford

EXPANSION initiated during and after the war has placed industrial plants in new areas and increased reduction and manufacturing facilities in communities already established. With added expansion interest has grown in possible area contamination from waste products. Evolved flue waste contains many chemical contaminants that may or may not cause concern; however, atmospheric pollution has always been a problem to industrial communities. For some time effects attributed to small quantities of compounds of fluorine in various waste gases have been studied by industrial, medical, agricultural, and associated interests.1,2 Aside from an article by Churchill, Rowley, and Martin in 1948,3 little has been published on the subject of fluorine in coal except by foreign investigators.

Jan 1, 1957

By T. D. Tiemann

The purpose of this writing is to make available additional data, not previously published, on the extraction of silica from certain iron ores of Wisconsin and Minnesota and to discuss a possible method of processing. Results of investigations on the extraction of silica from low grade iron ores have been previously presented and discussed in detail in AIME Transactions.1,2 All of the ores investigated are essentially nonmagnetic and consist mainly of hematite, goethite and quartz. Much of the quartz is microcrystalline, particularly in the taconites. The ore from the Cuyuna range contains in addition manganese oxides. Briefly, the method consists in digesting a sample of the ore under pressure in a solution of sodium hy-

Jan 1, 1965

By James R. Evans

Forecasting demand is an art as well as a science, and much personal judgment is required. National forecasts made for sand and gravel, crushed stone, and/or aggregate may be misleading or unhelpful locally. This is because of significant variation in demand within different geographic and/or political areas in the US, and/or the use of an inadequate data base and forecasting methodology. The best forecasts may be made for local or regional market areas, irrespective of geographic or political boundaries, provided a proper data base is available.1 The Bureau of Mines compiles detailed statistics on commodities sold or used in the construction industries and, therefore, is in an advantageous position to make national aggregate demand forecasts.

Jan 1, 1979

By M. G. Schuerger, D. W. Park

An improved gage for monitoring fractures in underground openings was successfully developed using the reflection photoelastic technique. The gage may be used to detect crack initiation in mine openings or tunnels so reme¬dial action may be taken to prevent further deterioration. Fringes concentrated around the cracks were spread by using rubber backing. Crack growth as little as 76µm (0.003 in.) up to as much as a 2.54-mm (0.1-in.) width were detect¬ed in this study. Variation of gage materials will provide alternative ranges. The feasibility of the method was tested and calibration was made in a laboratory study. Field study successfully demonstrated the capability of applications in detecting mine roof crack development.

Jan 1, 1984