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Spencer Gulf takes off from the Great Australian Bight cutting a 200 mile deep wedge of water into the South Australia coastline. A pale winter sun shines yellowly on the choppy surface of this body of water which is progressively more salty as it approaches Port Augusta at the head of the Gulf. Once Port Augusta thrived as a grain port and the speedy clipper ships began or ended their legendary races there. On the eastern shores of Spencer Gulf, farm land spreads away from the water's edge. The western side of the gulf meets marginal grazing land of acacia tree and salt bush. Part way down the gulf, there are two industrial towns facing each other from opposite shores; Port Pirie on the east and Whyalla on the west. These towns are like half brothers, the common parent being the founders of Broken Hill Pty. Ltd., (BHP) who began lead smelting at Port Pirie and discovered iron ore near Whyalla needed for the lead smelting process. The iron deposits later became the inspiration for BHP's iron and steel business.

Jan 10, 1964

By E. P. Barrett

THE high-frequency laboratory induction furnace with a rotating liquid crucible enables research workers to conduct certain investigations heretofore very difficult or impossible to realize because vessels are not obtainable that are capable of resisting the physical conditions or the chemical actions to which they are subjected. Applications for patents covering commercial uses of centrifugal liquid crucibles were filed in the United States in 1919,1 in France in 1925, in the United States and Germany in 1926,2 and in France in 1927.3 In 1928, Schuette and Maier,4 of the Bureau of Mines, reported the construction of a whirling table beneath a high-frequency induction furnace. SHAPE AND SIZE OF CENTRIFUGAL LIQUID CRUCIBLES When a vessel containing a liquid is rotated, the inner surface of the liquid takes the shape f a paraboloid under the simultaneous action of centrifugal force and gravity. The internal dimensions of the paraboloid rotating liquid crucible are governed by the diameter of the container and its speed of rotation. Melted Wood's metal was poured into cylinders 2 ½ in. in diameter, which were rotated at 180, 300, and 468 r.p.m. When the metal was solid, a slurry of plaster of Paris was added, and rotation continued until the plaster had set. Fig. 1, a photograph of sections f the cylinders, shows the effect f speed f rotation of the containers upon the shape f the inner surface f the rotating liquid crucibles.

Jan 1, 1938

By Jennings S. Cox

The following notes, prepared in 1908, as the result of a personal examination and extensive explorations under my direction in 1906, have been revised and greatly augmented after two subsequent visits and further explorations in 1910. The hard iron-ores of the south coast of Oriente Province, in the island of Cuba, have been known for many years, in fact one mine has been in operation for more than 20 years; but it is only within the past four years that the large mantle-deposits of brown ores of the north coast have attracted serious attention. A. C, Spencer' has described these ores in a paper, entitled Three Deposits of Iron Ore in Cuba, which refers to the Mayari, Moa, and Cubitas deposits. C. M. Weld,2 in a scholarly paper, The Residual Brown Iron-Ores of Cuba, has discussed the character and possible genesis of these deposits with particular reference to the Moa field, calling attention also to the Taco and Navas fields in addition to those described by Spencer. Descriptive articles with reference to the Mayari field, and a few words about the Moa deposit, have also appeared3 It is the purpose of the present paper to give some account of the exploration of the Moa deposit arid to call attention to its commercial importance. Location. The Moa district is situated on the north coast of the Province of Oriente, which is the most easterly province of the

Jan 1, 1912

By AIME AIME

THOUGH the Annual Meeting of the Institute-officially numbered 158 on the records was delayed a bit at the start by low steam pressure on the locomotives bringing members to New York, the crowd that finally arrived more than lived up to expectations, and the technical program had few difficulties because of absent authors or lack of competent discussers. The transportation difficulties were occasioned by the fact that Monday, Feb. 15, was the third coldest day in the 72 year history of the New York Weather Bureau, the official temperature being 8 below zero. The New York Central's premier train, the 20th Century, due at 9:30 a.m., arrived about 6:30 p.m., and the Commodore, another crack train from Chicago, was about equally late.

Jan 1, 1943

By Blair R. Benner

This paper describes the installation and operation of a Texas Nuclear on-line silica analyzer (NOLA) coupled with a Leeds and Northrup Microtrac particle-size monitor (Microtrac) at U.S. Steel's Minntac taconite concentrator. An automatic sampling system provides the NOLA with samples of final concentrate. After the sample is analyzed for silica by the NOLA, it is pumped to the Microtrac for size and surface area measurement. A sample is analyzed every six minutes, providing the control room with the silica concentration, the percent passing 270, 400, and 500 mesh, and an equivalent Blaine surface area number. When fed a slurry of final concentrate containing between 20 and 70% solids and 5 to 6% silica, the NOLA analysis is within ±0.2% of the wet chemistry silica. The agreement between the Microtrac output and standard screen analyses is ±1.2% at 270 mesh; ±1.5% at 400 mesh, and ±2% at 500 mesh. The poorer disagreement at the finer sizes is mainly due to inaccuracies in screening at 400 and 500 mesh. The agreement between Microtrac surface area a d laboratory Blaine surface area is about 9 ±80 cm 2/g. These instruments provide rapid and reliable feedback information to the concentrator and feed forward information to the agglomerator.

Jan 1, 1984

UNITED ENGINEERING TRUSTEES, INC. James L Head, '55 E C Meagher, '52 Gail F Moulton, '53 Advisory Committee to Real Estate Committee Cleveland Dodge Herbert Hoover J Paul D Merica THE ENGINEERING FOUNDATION E. R Kaiser, '54 W. M Peirce, '52 E C Meagher, ex officio as President, UET Research Procedure Committee E. R Kaiser ENGINEERING SOCIETIES LIBRARY BOARD James L Head, Chairman Frank T Sisco, '54 E M Wise AMERICAN STANDARDS ASSOCIATION Mining Standardization Correlating Committee Otto Herres, '53 J K. Richardson, '53 H H Otto, '53 E W Bullard, '53 - Alternate

Jan 1, 1952

By Stephen Birch

The Chitina mining district of Alaska is located at the headwaters of the Chitina and Copper Rivers. At present, the only producing mining properties are the mines of the Kennecott Copper Corpn. and the Mother Lode Coalition Co., which are situated 196 miles from Cordova, the port of entry. The first claims, later acquired by the Kennecott Mines Co. and afterwards transferred to the Kennecott Copper Corpn., were discovered in 1900. The Copper River & Northwestern Ry., which connects the mines with tide water at Cordova, was completed in the spring of 1911. Contemporary with the construction of the railroad, aerial tram equipment was brought to the mines by pack train and a tramway, 3 miles long, connecting Bonanza mine with the proposed railroad terminal, was finished, enabling shipments of high-grade ore to be made immediately the railroad was completed. A mill to treat the lower grade ore was begun the same year. The Kennecott company's holdings consist of 111 mineral claims. The Mother Lode Coalition Mines Co., which is controlled by the Kennecott Copper Corpn., owns 73 claims adjoining the Kennecott holdings. All data on operations and geology refer equally well to the Mother Lode property. Geology The general geology of the district has been covered by the U. S. Geological Survey1 and the geological features of the mines have been carefully studied by A. M. Bateman, in his capacity as consulting geologist to the company.2

Jan 1, 1925

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 Henry G. Petrow, Edward S. Porter

MAJOR occurrences of lignite with significant uranium concentrations have been reported in western parts of the Dakotas, especially in Harding County, S.D., and Billings and Slope counties, N.D. Samples containing as much as 2 pct U3O8 were received at the Winchester Laboratory, but those deposits reportedly of major significance have generally contained 2 to 4 lb of uranium per ton of lignite. Most of the uranium appears to be associated with the carbon in the lignite as a urano-organic complex, although in most instances analysis of inorganic material has shown uranium values. Molybdenum is similarly associated with the carbon, and its concentrations generally parallel the uranium. The noncarboniferous material is mainly composed of gypsum, jarosite, bentonite, sandstone, and miscellaneous carbonates and silicates. The heating value of these lignites has been determined as about 3500 Btu on a dry lignite basis. The ash content of lignite has varied widely, the important samples containing 30 to 60 pct ash on a dry lignite basis. Because of the significant upgrading of uranium values obtained by ashing the lignite, and because recovery of uranium from raw lignite presented formidable processing problems, major emphasis at Winchester has been placed on devising methods to recover uranium from lignite calcines. Proper roasting removes the problem of organic fouling of solutions, reduces the size of the leaching plant for an equivalent uranium throughout, and generally provides equal or better acid leaching efficiency with less acid than can be obtained from the raw lignite.

Jan 9, 1957

PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 ROBERY W HUNT 1883 JAMES C, BAYLES 1884-1885 ROBERT H RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B POTTER 1888 RICHARD PEARCE 1889 ADAM S HEWITT 1890 JOHN BIRKINBINE 1891-1892 H M HOWE 1893 JOHN FRITZ 1894 J D WEEKS 1895 E G SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898 JAMES DOUGLAS 1899-1900

Jan 1, 1952

By H. W. Seamon

THE data here given were obtained by 1500 tests made, by the United Verde Copper Co. to determine the most economical air pressure for the operation of hammer drills under the varying conditions of use, and to investigate the variation in drilling speed at different air pressures Twelve models of drills were used at gage pressures ranging from 40 to 130 lb. No effort was made to harmonize theory and practice; but rather to formulate empiric rules that would cover the. average variation of the results obtained. These rules on the performance of hammer drills, based on the air pressure as the main variable, however, are not necessarily of universal application, but they apparently satisfy the results obtained in this series of tests. The drilling conditions at this property vary widely; an average of twenty-one machine shifts to a 3-ft. (0.9-m.) round has been found necessary in some of the development work, while an, advance of 56. ft. has been made in seven shifts in the "oxide" ground. This range pre-eludes the adoption of one type of drill as a standard; consequently almost every kind of hammer drill sold in this country has been tested. At present, sixteen models are in use, of which two types of the heavy (150 to 160 lb.) mounted drills, one of the light mounted drill, one stoper, and two hand plugging drills are considered as standard.

Jan 1, 1921

By K. L. Fetters, F. M. Walters

ALL previous records were broken by the Iron and Steel Division, in the number of sessions, the number of papers, and the attendance. In addition to ten papers (all preprinted) on properties, structure, aid hardenability of, carbon and alloy steels, eight formal papers were presented on one or more phases of steelmaklng, and a symposium on the determination of hydrogen and nitrogen in steel. This last started at 2 p.m. and was going strong with more than a third of the audience still present at 6 p.m.

Jan 1, 1944

Jan 1, 1936

Jan 1, 1936

By Dick Whittington, W. R. Taylor

GENERAL In mid-1974, a representative of ARCO Petroleum Company walked into our Austin offices and asked for a permit for ARCO's first Clay West Mine site. This was the first in situ uranium mining permit issued in the United States. That initial permit, issued in January 1975, was for three acres. The four years since have been characterized by growth and change. Today there are 16 permits approved for approximately 1,540 production acres issued to five companies at eight sites in four counties. There are approximately seven additional permit applications being processed or on the verge of being submitted for an estimated 2,000 additional acres of production. As a rough gauge of the financial scope of this activity, at the typical 40 production wells per acre and an estimated $2,000/well, operators hale installed or committed $122 million for production wells. This does not account for the exploration and development wells installed to delineate the ore or the cost of processing facilities for extracting the uranium. HISTORY OF URANIUM MINING IN TEXAS Information I have concerning early in situ uranium mining activities is "sketchy" but the apparent first on-site test of in situ uranium mining was conducted between 1967 and 1971 at the Dueterstat site, north of Yorktown in Gonzales County, by City Service. Others ran tests at the Bruni site in Webb County and the Burns and Clay West sites in Live Oak County in the mid-70's. During this period, Texas Water Quality Board personnel in the central and district offices maintained a general surveillance of these various test activities. Regulation of in situ uranium mining was formalized with the issuance of a permit in January 1975 with the advent of ARCO's initial production scale (3 acre) effort in the Clay West area at the Moser mine site. Since 1975, the accelerating rate of mining and exploration activity is noticeable. There were 16 exploratory rigs operating early in 1977. This year, the rig count is averaging 46--a 287% increase. HISTORY OF LEGISLATION Paralleling this mining activity was state and federal legislation which subjected in situ mining to environmental regulation. The following is a brief chronology of the legislation that is directly or indirectly related to uranium mining. As most of you know, disposal wells are an integral part of most in situ uranium mines operating in Texas. They are used both during production and during aquifer restoration following production. The wells are regulated by the Texas Injection Well Act, enacted in 1961 by the Texas Legislature. In 1967, the Water Quality Act established the Texas Water Quality Board, and provided for the regulation of water quality by the so-called permit system. In 1969, the Solid Waste Act was enacted by the Texas Legislature. The legislation provides for control of wastes from manufacturing, mining, and agriculture. This Act regulated uranium surface mining activities until 1975 when the Texas Surface and Mining Reclamation Act placed responsibility with the Railroad Commission for uranium open-pit mining and surface mining of coal and lignite. In 1972, the Federal Water Pollution Control Act (Public Law 92-500) was passed. This legislation forms the legal base for the NPDES (National Pollutant Discharge Elimination System) and the subsequent point source effluent guidelines and standards. The November 6, 1975 issue of the Federal Register published interim final rules for Best Practical Treatment levels for effluent discharges from ore mining and dressing operations. Litigation was immediately initiated by eleven companies against these proposed rules, and they are currently being reconsidered for reissuance in 1979. In 1974, the Federal Safe Drinking Water Act (Public Law 93-523) was enacted. A part of this legislation is the Underground Injection Congrol Program. The regulations implementing this program have undergone various public hearings and it is expected that they will be published in the Federal Register before the end of 1978. In 1975, the Texas Surface Mining and Reclamation Act (Senate Bill 55), providing for the Railroad Commission's authority to require reclamation of surface mines, was passed. In 1977, an amendment to Senate Bill 55 was introduced that proposed to place regulation of in situ mining of coal, lignite, and

Jan 1, 1979

Jan 1, 1929

By James W. Dally, William L. Fourney, Anders Ladegaard Peterson

For the past 3 years, the authors have been conducting research sponsored by the National Science Foundation (RANN) to improve the process of excavation by drilling and blasting. The approach followed has been experimental where the development of stress waves and fractures initiated at the bore hole have been investigated in order to obtain a complete understanding of the dynamic fracture process. The second step in the approach has been to introduce modifications in the drill and blast procedure which will permit closer control of the fracture process. The laboratory investigations involve high speed photography where the dynamic fracture process is recorded with a Cranz-Schardin 1, 2 multiple-spark camera. The camera is equipped with 16 spark gaps which are pulsed at 25 K volts to produce an intense but very short (0.5 sec) flash of light. The camera is capable of recording 16 photographs of a dynamic event at framing rates which can be varied from 30,000 to 1,500,000 frames per second. The exposure time is sufficiently short to stop motion associated with detonating explosive charges and to make visible the details of the fracture process at a bore hose. The bore hole in a massive intact rock formation is modelled with a two dimensional plate containing a circular hole to represent the bore hole. The model material employed is a transparent polyester known commercially as Homalite 100.* This polymeric material is extremely brittle as evidenced by its extremely low fracture toughness of [ ]. The fracture toughness is a measure of the ability of a material to resist the propagation of flaws or small cracks. In comparison, Schmidt3 has recently measured the fracture toughness of Salem limestone and determined [ ]. Thus, the Homalite 100 should closely model the brittle nature of rock where fractures occur at small flaws and propagate without any apparent plastic deformation. Homalite 100 is also birefringent, which indicates that it becomes optically anisotropic when subjected to either static or dynamic loads. Circularly polarized light is transmitted through the loaded Homalite 100 model in a polariscope4 and the birefringence produces an optical interference pattern which is called a fringe pattern. For dynamic photoelasticity, the multiple-spark camera is equipped with polaroid filters to produce the circularly polarized light required to generate the photoelastic fringe patterns. An example of a singlespark frame showing a fringe pattern from a typical experiment is presented in [Fig. 1]. The photograph was taken 0.000072 sec (72 sec) after the detonation of the explosive charge. The circular fringes are due to the outgoing dilatational or P type stress wave and travel with a velocity of 85,000 in. per sec (2260 m/sec) in the Homalite 100. The P wave is followed by a second lower velocity stress wave known as the shear or S type wave which propagates at a velocity of 49,000 in. per sec (1245 m/sec). In the local neighborhood of the bore hole, several radial cracks are visible. These cracks propagate at essentially a constant velocity of 15,000 in. per sec (380 m/sec) prior to arrest. The fringes about the crack tips and in the local region of the bore hole are primarily due to the residual gases contained in the bore hole after the explosive charge was detonated. Sixteen frames similar to this one are recorded during the experiment to give full field visualization of the dynamic event at 16 discrete times over its duration. The fringe order number N is related to the difference in the principal stresses of and 02 according to a stress optic law4: [ ] where f0 = material fringe value, and h = model thickness. The wholefield dynamic-fringe patterns provide a basis for simultaneously observing the interaction between propagating cracks and the stresses which drive these cracks. Fracture Control Experiments Improvements in the efficiency of the drill and blast procedures must involve close control of the fracture process following the detonation of an explosive charge in a bore hole. By control it is implied that the number of cracks initiated and the location of each crack on the wall of the bore hole can be specified. Control also, involves orienting each crack and maintaining the crack path and velocity until the specified crack length is achieved. If the entire fracture process can be controlled, then rounds can be designed to optimize volume removed. fragment size and minimize costs. One area of blasting where fracture control is vitally important is in underground excavation where the strength and stability of the rock walls must be maintained and smoothness and precision of the walls must be achieved. The smooth blasting method is one of the most commonly employed procedures for achieving some degree of fracture control. In smooth blasting, the central region of material is first removed, and then the final row of closely spaced undercharged or cushioned holes are fired to remove the final volume and produce a smooth wall. In some instances, unloaded or dummy holes between the loaded holes are recommended to guide the fracture plane. This investigation pertained to an evaluation of 3 features of the smooth blasting process. These included (a) the effect of stress reinforcement on fracture by simultaneously firing 2 charges; (b) the influence of a dummy hole on control of the fracture planes between 2 simultaneously fired charge holes; and (c) the influence of dummy hole spacing on fracture plane control.

Jan 1, 1979

WALTER N. CRAFTS,* Toronto, Canada (written discussion?).-During the forging of 9.2-in. shells -for the United States Army, it was noticed that better results were obtained in certain instances when test bars had been held sometime before pulling. An investigation, therefore, was made by our metallographer, Mr. F. M. Arnold, to determine the effect of seasoning. The forging consists of a single operation, piercing a solid cast blank. The test sections were cut from the walls by an oxyacetylene flame, one piece from the nose end and one from the base on the opposite side. The test pieces were not heat treated in any way and the tests and seasonings were carried on at normal atmospheric temperatures. The specifica-tions were as follows: Standard 2-in. test bar, 0.505 in. in diameter; elastic limit, over 19 long tons, or 42,500 lb.; ultimate stress, 39.6 to 49.1 long tons, or 87,500 to 110,000 lb. per sq. in.; elongation, over 13 per cent. As a preliminary test two heats were selected; BP555, which was tested and reported failed on elongation on Aug. 20; and B01771, which was tested and reported failed on Aug. 24. On Aug. 29, retests were cut and machined from the same shells and held till Sept. 3 (5 days) when they were pulled. Both sets of results are given below.

Jan 12, 1919

By Paul M. Tyler

THE farmer pays the phosphate miner! Phosphorus is used in fireworks; goes to battle in military smoke screens, incendiary shells, and tracer bullets; and, in vermin destroying pastes, does its part in the war against insects. A lemon phosphate can be had for a nickel at most soda fountains, and tens of thousands of tons of phosphate rock are mined annually for use in the food industries, chiefly for making monocaleium phosphate baking powder. Sodium phosphate cleaning, washing, and scouring compounds consume substantial quantities: the iron and steel industries buy a few thousand tons yearly to make ferrophosphorus and to balance foundry-iron furnace charges; and even nonferrous metallurgists use a little for phosphor bronze and other alloys. Phosphoric acid, its salts, and diverse other derivatives of this versatile element have countless applications, and industrial outlets are increasing rapidly, especially in the United States. Nevertheless, in this country nearly 90 per cent and in the whole world fully 95 per cent of the phosphate rock consumed is absorbed ultimately in agriculture.

Jan 1, 1938

By G. J. Wolga, W. W. Tyler, A. C. Wilson

THE physical properties of uranium have been reviewed by Katz and Rabinowitch.1 Their review includes thermal conductivity data for ternperatures above 375°K. Recently, Mendelssohn and Rosenberg' have published data on the thermal conductivity of uranium from 2" to 20°K. Our measuremerits indicate the temperature dependence of the thermal conductivity in the temperature interval from 20" to 300°K. Electrical resistivity and thermoelectric power were measured on the same sample. The material studied was normal uranium which had been heated at 700°C in a lead bath for 10 min and then quenched in a water bath held at 50°C. From this material a rod M in. in diameter and 2 1/2 in. long was machined. Two 0.040 in. holes were drilled into the rod 1 3/4 in. apart. Copper-constantan thermocouples for temperature and potential measurements were soldered to copper pins which were pressed tightly into these holes. Details of the equipment and experimental techniques used in making the measurements have been described elsewhere." Fig. 1 shows micrographs of a section of the sample studied. Fig. la was taken with unpolarized light and shows impurity inclusions, probably uranium carbide. Fig. lb, showing the same field, was taken with polarized light and gives some indication of the grain size and twinning within the grains. Experimental Results Thermal conductivity and electrical resistivity data are shown in Fig. 2. Table I shows values of

Jan 1, 1954