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Manganese deposits discovered in Maine may solve one of the problems facing the steel industry today. Diamond drilling is scheduled to start in Aroostook County to determine whether the ore is of acceptable grade. The Bureau of Mines estimates the deposit contains several hundred million tons. If true, it means about a 30-year supply. The steel industry presently imports about 90 pct of its needs. Noranda Mines, Ltd., is planning a sulphur-iron plent for Ontario's Niagara Peninsula. Although contracts have not been signed, a substantial agreement has been reached with American Cyanamid, Ltd., whereby the Noranda plant would be constructed adjacent to Cyanamid's chemical plant at an estimated cost of million. The unit would treat approximately 100,000 tons of pyrite concentrate annually. San Manuel Copper Corp., wholly-owned subsidiary of Magma Copper Co., is asking the RFC for a $111.28 million loan for development of a copper orebody in Pinal County, Ariz. The property s said to be capable of producing 10 million tons of ore annually. San Manuel plans to construct facilities for processing 30,000 tons of ore and for smelting 800 tons of concentrate daily. An Aeromagnetic map covering 120 sq miles of the Wichita Mountain area in southwestern Oklahoma indicates a possibility of iron production from titaniferous magnetite deposits of the Raggedy Mountains, northwest of Lawton. The map shows an area in the north central part of the region which may prove favorable to further development.

Jan 1, 1952

By Leonard Bernstein, Harry Bartholomew

MANY of the properties of metals and alloys are structure dependent. Not the least of these is the grain structure. For example, in producing alloy bonds between silicon or germanium and gold-alloy foil at temperatures above their eutectics (which are, respectively, at 370" and 356°C) but below the melting points of the individual constituents, it was found that wetting was more complete with a fine-grain structure than with a coarse-grain structure. In cases where the assemblies were held together for long periods of time at elevated temperatures, wetting was not as critically dependent on the grain structure as was the case for shorter periods of time. When liquid phase forms, it first forms in the grain boundaries due to the fact that most of the impurities are concentrated at the grain boundaries and that most impurities tend to lower the melting point of the gold alloy somewhat. In addition, grain boundaries are at high-surface free-energy levels and are thus in a more favorable condition to initiate good wetting. A fine-grain structure will have more grain boundaries per unit area than coarse-grain structure thereby making wetting somewhat easier. To make the grain structure of an alloy sys- tem visible, a satisfactory method for differentiating between the different grains of which the system is composed must be employed. For the alloy bonding system previously described, the grain structure on the foil surface is of primary interest. Conventionally used etchants for the gold-alloy system will not adequately delineate grain boundaries in their structures. For this reason an alternate method is proposed for those cases where such a determination is necessary. Foil between 0.0005 and 0.005 in. thick has been used in this determination. The equipment used in this investigation was described in a previous publication.' Essentially, it employs a resistance-type filament which can be heated up very rapidly and cooled very rapidly. A thin refractory material is placed on top of the heating element. This refractory material may be molybdenum, tantalum, tungsten, or even ceramic but its thickness should be less than 0.010 in. to minimize the temperature gradient across it. The gold-alloy foil is placed on top of this refractory material. The temperature of the heating filament is raised to 900°C and cooled down to below 100°C in 5 to 10 sec. During this cycle, the foil can be observed to plastically deform due to its own weight. With no further chemical etching, this assembly is then viewed under a standard metallurgical microscope and the grain size measured. Fig. 1 is a Au-1 pct Sb alloy at 400X magnification and Fig. 2 is a Au-1 pct Ga alloy at 130X. This technique has proved to be an adequate means for controlling processing conditions in producing large quantities of gold alloy foil.

Jan 1, 1963

INTRODUCTION Besides the European export credit agencies covered in Ted Rides' paper in this Chapter, other agencies are also active (see Appendix) but the most notable for mining projects are The Export-Import Bank of the United States ("US Exim") and the Export Development Corporation ("EDC") of Canada. Mexico's Fomex is basically a short-term trade-finance fund administered by the Central Bank. US Exim This independent agency can provide loans, guarantees, and insurance. Like all export-credit agencies, its mandate is to support the export of goods and services from the US as a means of competing against other countries' products. If a piece of mining equipment can only he made in the US, the US Exim may very well not provide any financial assistance. (It is important not to place the order for any item for which export credit is sought because, once ordered, the situation is no longer competitive in US Exim's eyes.) Direct Credits and financial guarantees ("buyer credits") are commonly in amounts greater than 85 million and for terms longer than six years. An example here is the $48.5 million provided to PT International Nickel Indonesia (see Robert de Gavre's paper in Chapter 12). US Exim usually requires a 15% downpayment and, therefore, finances up to 857 of the goods; less if the US content is lower. The dollar funding can he US prime, London Interbank Offered Rate (LIBOR), or other sources. Exim can fund in either or both of the following ways: 1. Under a US bank Letter of Credit ("L/C") 2. Reimbursement to the buyer/borrower via a US bank account. US Exim will, without charge, issue a preliminary commitment. It will, however, need to approve the various credit agreements and prefers to tie other parallel financings into one loan agreement. US Exim's total commitments are large, up to $5R billion in aggregate under various programs. US Exim has been the world's leader in medium-to long-term minerals project financings/ co-financings but suffers from (i) aggressive foreign export-credit competition whereby other nations mix in soft-loans or aid programs ("mixed credits") to increase the percentage financed and lower the interest margin and (ii) an imbalance in its own cost of funds. A common US Exim package would be as follows: 15% Banks under US Exim guarantee, floating rate over prime or LIBOR. 35% US Exim funding, fixed rate 35% Pefco funding, fixed rate 857 Drawn down pro-rata under US bank L/C 15% Cash down payment (may have been financed within a project/corporate credit) 100% Repayment usually begins six months after planned start-up in equal semi-annual instalments, with the banks usually paid out first, Pefco next, and US Exim last. Medium-term credits ("supplier credits") are issued for US equipment exports for terms up to five years, again for 85% of the equipment costs although the exporter is expected to bear at least 10% out of that 857 for its own risk. The buyer is required to be a first-class credit such as some governments or highly credit-worthy companies. Otherwise a bank L/C would be required. (This may be wrapped into an overall project-finance package for a minerals development. The project-finance banks provide an L/C to US Exim instead of funding that portion themselves.) US Exim guarantees 100% of the political risk and either 85% or 95% of the commercial risk for

Jan 1, 1985

CENTRAL EMERGENCY COMMITTEE Chairman, MRS. H. N. SPICER As no further requisition will be Made for knitted garments, for the boys of the 27th Engineers, all completed garments and wool have been collected and returned to Mr. W. R. Ingalls, and the activities of the

Jan 12, 1918

Mellon Institute of Industrial Research, University of Pittsburgh, Pittsburgh, Pa. The Mellon Institute of Industrial Research has carried on for years research and investigations for all type and manner of indus¬try. One of the provisions of the foundation of the Institute is the

Jan 1, 1933

By F. C. Blake

The best method for the estimation of copper in ores and secondary products is that proposed by Dr. Steinbeck* for the award offered by the Mansfeld'schen Ober-Berg-und Hutten-Direction. It is based upon the decolorization of the blue ammonia solution of copper by potassic cyanide.7 It is necessary for the accurate estimation of copper in arsenides that the arsenic be separated from the copper before the ammonia solution is made. The presence of a notable amount of arsenic renders the titration by potassic cyanide inaccurate, the end reaction being obscured by the appearance of a yellowish-green tint towards the end of the titration. The change of the color of the ammonia solution from blue to the tint caused by the presence of arsenic cannot be used for an end reaction, for the intensity and quick appearance of the latter color depend upon the amount of arsenic present in the solution. In the analysis of speise, the method of separating the copper by an oxidizing and reducing treatment in the muffle, to volatilize the arsenic, gives poor results, and there may easily be some loss of the weighed sample. The separation of the precipitated sulphides of arsenic and copper by treating with sodic sulphide, gives good results, but the process is tedious. I have used the two following methods, which are simpler and more expeditious than those mentioned, with good results

Jan 1, 1881

No greater opportunity for public service has ever been presented to the engineers of the United States, as a class, than the campaign to make thrift a permanent American habit, conducted through the Savings Division off the Treasury Department. The engineer owes a duty to his community, to his country, by reason of the very fact that he is an engineer. By reason of his position and influence, his education and experience, he owes to his country the duty of public service. The public understands that the opportunities of the engineer have allowed him to equip himself to handle logically and properly questions affecting the public. He has been trained to maintain a constructive viewpoint. His work is constructive and he builds for the future. The qualities that the public deems necessary for public service have been bred in him. The time has gone by when the professional man can perform his whole duty to himself and his community by shrouding himself and his calling in mystery and locking himself away from the public in office or laboratory. The duty of public service is calling for every man whose training has fitted him to perform that service. The engineers of the country have demonstrated their capacity and their willingness for public service. Throughout the war period they, have been found in every branch of governmental and. civilian activity which could contribute to national success, doing their share to promote national efficiency. Their duties are not over.

Jan 7, 1919

Engineers and masters of enterprise are waking fast to the realization that there is something more in the relations of employer and employee than mechanical output, which can be measured mathematically, and that the human side of service must receive greater consideration for the future. So much has been said and written on this subject that it has passed into a truism. Should not the same element, long neglected, be considered as of even greater importance than questions of "administration and membership, in the plans of engineering societies? Should mutual service and interest end with mere technical output by members and the rendering of care and management by officers? The world is recognizing, as never before, obligations for service to fellowmen clue from all, high or low, in rank or wealth. Our technical societies, organized for professional protection and advancement, are, insensibly to themselves, almost without conscious intent, widening their field of service to members and dealing heartily with questions broader than technique. Those who are doing such service find unconsciously more and more satisfaction in work so rendered. The growth of knowledge that comes to subaltern engineers or veterans by converse and contact with their fellows, working along and versed in the same subjects, brings interest and friendship. In this way are built some of the warmest friendships of life, coming as incidental and pleasurable result of meetings undertaken for other purposes. Should not the friendly purpose, the desire for service one to another, and es-

Jan 1, 1919

By A. G. Metcalfe, R. P. Elliott, F. A. Crossley

THE texture method (utilizing monochromatic copper radiation) was applied to determine the orientation of the columnar grains of two vacuum cast beryllium ingots of 3 in. diam. Samples were mounted in a fixture as illustrated in Fig. 1, which permitted rotation and translation in order to approximate the method used for wires. The specimens were aligned so that the major axes of the columnar grains were parallel. Rotation was around the growth direction. After each translation the specimen holder was rotated 2 deg (1 deg for the samples from the second ingot) until a range of 30 deg on either side of the vertical was covered. The speed of translation was 1 mm per sec. A representative Debye pattern is shown in Fig. 2. The pattern was compared with theoretical patterns for various orientations. Also shown in Fig. 2 is the disposition of reflections on the (10i0), (0002), and (1011) Debye rings for the two possibilities that growth is either in the <10i0> or <ll30> direction. It is apparent that no significant preference for the direction of columnar growth is indicated. It is considered that the lack of a preferred orientation is due to the occurrence of the phase transformation (reported by Martin and oore&apos; to occur above 1250 "C) which masked the original solidification orientation. This research was supported by the United States Air Force under Contract No. AF 33(616)-5911, monitored by the Materials Central, WADD, Wright-Patterson Air Force Base.

Jan 1, 1962

By Charles Macdonald

Wrought-iron eye-bars for bridges and roofs, designed upon what is known as the pin connection system, have been successfully manufactured in this country for some years. The most approved methods employed have been the hydraulic upsetting process, and by die-forging under a hammer. In upset eyes the fibre of the iron is necessarily much distorted ; and in bars of considerable size, this disturbance seriously impairs the strength of the connection. Mr. Collingwood, in discussing my paper on "Proportions of the Heads of Eye-bars," read before the American Society of Civil Engineers, Jan. 21st, 1874, submitted sketches of certain bars intended for the anchorage of the East River bridge, which had been exposed to the action of sulphuric acid a sufficient length of time to thoroughly cleanse the surfaces, and expose the condition of the fibre. These sketches are here reproduced for the purpose of illustrating the effect of this method of manufacture. In Figs. 1, 2, and 3, it will be observed that the fibres at A, and E, have been folded back upon: themselves and otherwise twisted and disturbed, in a manner not calculated to inspire confidence in the integrity of the connection. To compensate for this defect, a large excess of metal is thrown into the eye; but a method of manufacture which involves such a necessity, even although it be the one giving the best results thus far, all things being considered, is far from being perfect.

Jan 1, 1879

By A. Stumpf, Y. Berube

An experimental apparatus for studying the aqueous oxidation of sulfide minerals is presented. The oxidation kinetics for molybdenite in solutions of caustic soda and dissolved oxygen are discussed; results of leaching experiments on chalcopyrite concentrates are given. Preliminary results on the transfer of oxygen into water are also discussed.

Jan 1, 1974

By Robert N. McIndoo

A good tire program must begin at the top; management must have an awareness of the tremendous potential for cost saving that tires represent. At Reserve Mining Co., tires account for 33% of the cost of maintaining its 44 tractor-trailer side-dump haulers and 22% of its 32 rear-dump trucks. In comparison, engine overhauls account for only 6% of the maintenance dollar. Doubling the present engine life would save only 3%. The open-pit mine, located near Babbitt, Minn., moves about 46 million t/y with its off highway fleet. Mine roadways total in excess of 160 km (100 miles) and about 1200 tires are in active use at any given time.

Jan 3, 1978

By K. Adam

Grinding in steel mills adversely affects the flotation of pyrrhotite. The electrochemical nature of inter action between pyrrhotite and active metals was investigated by contacting pyrrhotite with platinum at different applied potentials. Flotation tests, scanning electron microscopy, Auger electron spectroscopy, and X-ray photoelectron spectroscopy were wed to examine the surface properties of pyrrhotite. The formation of hydroxide or oxide and sulfate species of iron through the oxygen reduction reaction at the cathodically polarized surface of pyrrhotite was shown to be the mechanism responsible for the reduced floatability of pyrrhotite.

Jan 1, 1985

Climax Molybdenum Co. has contracted with the Government to operate its property at Climax, Colo. at maximum capacity for five years. Substitution of synthetic lubricants, polyalkylene glycols and their derivatives, for petroleum products in certain industrial applications is yielding substantial savings in production costs and improved operation of mechanical equipment.

Jan 1, 1951

By R. S. Sandhu, S. H. Advani, J. K. Lee, B. L. Aboustit

A comprehensive finite element formulation for thermo-elastic consolidation based on a general variational principle is presented Sample one dimensional problems associated with isothermal consolidation, heat conduct ion, and thermo-elastic consolidation are presented. In addition, evaluations of thermo-elastic consolidation for an underground coal conversion field site are conducted.

Jan 1, 1982

By Emmanuel Detournay, Charles Fairhurst

A method is proposed for computing (a possible solution of) the ground reaction curve, for use in tunnel support analysis, in cases where the initial stress field is not hydrostatic. Rock around a circular tunnel is assumed to behave as an elasto-plastic material with a Mohr-Coulomb yield envelope.

Jan 1, 1982

By AIME AIME

M R. WEIGEL&apos;S present position as Chairman of the Institute&apos;s nonmetallics group arises from twenty years of experience in that field, from 1921 to 1926 as mineral technologist for the Bureau of Mines, in Washington, and since then for the Missouri Pacific R.R. Co., with headquarters in St. Louis. This rail- road serves an extensive region in and about the southern central states, from Omaha to the extreme southern tip of Texas, and from southern Illinois to Pueblo, Colorado, and it is Mr. Weigel&apos;s job to get as much freight for the road as possible from the mineral industry in this area. Much of the present and potential mineral production is in the non- metallic group.

Jan 1, 1940

By G. R. Love

i\ program has been written which allows fully automatic conversion of data for X-ray intensity, as a function of time, to finished conventional pole figures. The program accepts input data in the serial order in which they are taken and is therefore immediately compatible with automatic data-acquisition devices. From these data taped instructions are prepared for the Calcomp plotter to construct ink-on-paper drawings. Because both Siemens and Norelco pole figure goniometers are used in this laboratory, the program was written for pole figure data obtained from one or more interpenetrating spiral scans during which both the polar angle, @, and the equatorial angle, a, are varied simultaneously and continuously. The reference direction for a scan, that is the point @ = 0 deg, may be chosen coincident with either the normal direction (N.D. figures) or the rolling direction (R.D. figures). In either case the plotted figures are drawn with the transverse direction (a = 0 deg) at the right and the rolling direction at the top. The full, circular, pole figure is drawn as two semicircular figures labeled "front side" and "back side". As presently constituted, the program will also accept data from circular scans taken at constant values of @. In every case the angular coordinates of each intensity entry are generated in the computer from a relatively small number of auxiliary data. The X-ray intensity data are corrected for background scattering by direct subtraction of the intensity measured with 28 set appropriately "off" the Bragg angle. It is possible to enter this correction as an additional spiral scan through the a, @ space; because the background correction does not normally vary rapidly enough to warrant this detailed a determination, the background corrections are entered as one or more auxiliary data. All data are normalized to a multiple of random intensity. The data taken in this laboratory for N.D. figures are normally taken in a reflection geometry from from sheet samples and do not extend beyond <p = 75 deg; for these data random intensity must be determined from separate experiments and entered as auxiliary information. When the auxiliary information is not available, a number is chosen to give intensity values normalized to a scale of 1 to 10. In this laboratory, R.D. figures are based upon hemispherical samples for which data are taken out to @ = 90 deg; for these data random intensity is calculated by direct numerical integration of . sin @ d@ using the trapezoidal rule and the background-corrected values of the input data. Points necessary to the construction of the pole figure are identified by simple linear interpolation between adjacent data points to determine the loci of contour lines. Points lying on a given contour are connected to one another with straight-line segments and the search-calculation-drawing sequence is patterned to assure that different contour lines do not cross, that a single line does not branch, and that lines do not end in space. However, so that there be no ambiguity in the data presentation, all contour lines end at the limits of the input data. Since the curves are constructed of straight-line segments, they are not continuous in their derivatives. However,

Jan 1, 1969

By ERNEST W. ELLIS

MORE or less contradictory findings as to the most satisfactory feed for concentration tables of the Wilfley type is shown by the diversity of opinion among experimenters. Prof. R. H. Richards,l as a result of his work, favors classification. On the other hand the work of Messrs. Cox, Gibbins, and Porter,&apos; of McGill University, points in general to the desirability of screen-sized feed The ore used was obtained from the West mill of the Bunker Hill and Sullivan Mining and Concentrating Co., Kellogg, Idaho, and consisted of argentiferous galena in a gangue of quartzite and siderite. The natural feed was taken from the launder supplying the Fahrenwald classifier. Classified feed was collected from each of the ten spigots of this same classifier. From the natural feed the screen-sized feed was pre- pared in the laboratory. All three types of table feed were therefore derived from the actual mill circuit of a large plant.

Jan 1, 1926

* George M. Humphrey, president of the M. A. Hanna Co. and of the Iron Ore Co. of Canada, has announced arrangements for financing the development of the Labrador-Quebec iron ore deposits in the total amount of $200 million. Plans call for immediately beginning the construction of mining, railroad, and handling facilities, and contemplate the start of ore shipments in 1955 which will reach 10 million tons a year shortly thereafter. Total drilled and proven ore now exceeds 400 million tons of high grade open-pit ore with prospects for large additional tonnages. Capital structure of the company authorizes up to $125 million of first mortgage bonds, $40 million of income debentures and $60 million of common stock.

Jan 12, 1950