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By Edward L. Vickers

The Pacific rim countries, comprising more than half the globe, represent a complex mix of developed and developing nations. The area comprises a large segment of the industrialized world. Within its boundaries are also found many of the world's greatest mineral resources largely concentrated in the less developed countries. The conflicting objectives of these developed and developing nations are giving rise to changes in the traditional patterns of world resource development. Powerful political and socio-economic factors affecting the world today are having a great bearing on natural resource developments in the Pacific basin. New forms of partnerships have been emerging in developing nations which have had a great impact on the mining com- munity, lending institutions, as well as political relations. The United States and Japan have been substantially responsible in the past for the development of natural resources in this area of the world. Their role, however, is undergoing significant metamorphosis. The rapidly changing economic and social environment in the developing countries is producing new tensions which affect future collaboration between producers and users of natural resources. To understand current problems, I believe, it is worthwhile to examine historical trends in this area which may help defining alternatives facing us in the future. In modern times the United States was the first country in the Pacific basin to start development of resources on a massive scale. It began with the major exploration of the mineral-rich west of the United States and extended significantly later into Latin America and Australia. In the early 1950's, Japan became a significant

Jan 1, 1976

[NOTE.-The names of authors of papers are printed in small capitals, and the titles of papers, in italics. Casual notices, giving but little information, are indicated by bracketed page numbers. Large Roman numerals are volume numbers; small Roman numerals after volume numbers following titles indicate the page on which the presentation of the paper is mentioned; Arabic figures refer to the text of the printed papers.] A Use Classification of Coal, (ASHLEY) LXII [xiv]; LXIII, 782; Discussion: (HALL), 794; (ZERN) , 795; (ASHLEY), 795 Absorbent material, liquid-oxygen explosives, LXXI, 1251. Absorbents for liquid-oxygen explosives, LXIX, 292, 299. Absorption : cupellation : gold, special cupels, LIX, 194. primary and secondary, LIX, 213. ratio of silver to gold, LIX, 212. silver, specla1 cupels, LIX, 195. Absorption method, gasoline from natural gas, LIX, 584, 585. Absorptzon of Sulfur from Producer Gas zn Open-hearth Furnaces (NEAD), LXX, 176; Discussion: ( WATERHOUSE), 184 ; (REYNDERS) , 184; (KINNEY), 184 Accelerated wearing tests, bearing metals, LXIX, 973. Accident prevention, results, Utah, LXVIII, 360 Accident Prevention, 1919 (SINN), LXIII, [xiii] Accidents: causes in coal mines, LXXI, 1229. classification, Anaconda Copper Mining Co., LXVIII, 9. coal mining: comparison with metal mining, LXVIII, 360. pillar mining, LXVIII, 323. relation to method, LXVIII, 323 shafts, LXVIII, 207, 209 Utah, LXVIII, 363 - concentrating mills, Utah, LXVIII, 362 liquid-oxygen explosives, LXIX, 330, 339 losses through, LVIII, 65 metal mining, LXVIII, 361, 363. mine: causes, LIX, 652. curve of decrease, LIX, 655 days of greatest frequency, LIX, 657 human element as cause, LIX, 652, 653. intemperance as cause, LIX, 658 labor relation, LIX, 652 prevention, LIX, 653. record, New Jersey Zinc Co., Franklin mine, LIX, 655 time of greatest frequency, LIX, 657, 658 Utah, LXVIII, 360 prevention, LVIII, 65 report blanks, Anaconda Copper Mining Co, LXVIII, 13, 15. statistical base, Anaconda Copper Mining Co, LXVIII, 9 time lost, LVIII, 70 transportation, Clifton-Morenci district, LXX, 851.

Jan 1, 1926

By J. W. Spretnak, G. W. King

THE crystallography and morphology of 0-Al,Fe precipitates in an A1 + 0.5 wt pct Fe alloy have been studied by transmission electron microscopy. The alloy was cast in cylindrical ingots, 15 cm in diameter and 60 cm in length, and cooled slowly. The measured composition was 0.527 wt pct Fe, 0.001 wt pct Mg, and 0.003 wt pct Cu. Spectrographic analysis revealed no additional trace impurities. Thin slices were cut from the ingot and reduced by more than 95 pct by rolling to a thickness of 0.1 mm with no intermediate annealing treatments. These thin sheets were then vacuum-annealed for 1 hr at 612°C and air-cooled in their capsules. Thin foils for examination in the electron microscope were prepared by electropolishing. The precipitate is found in the form of oval platelets on the (110) planes of the matrix. The major axes of the platelets are parallel to the (110) directions of the matrix, and vary in length from 1/2 to 2 p. The thickness is about 1/10 p. Examples of platelets, both in the plane of the foil and normal to the foil, are shown in Figs. l(a) and l(b), respectively. lack' found that ?-A13Fe (more correctly All13Fe4) belongs to the monoclinic system. Using Black's structural data and simultaneous electron-diffraction patterns from the matrix and precipitates, the habit planes and directions were determined to be: (00l)? || (110)Al [100]? || [001]Al The orthogonal crystallographic axes of the precipitates are accurately in the habit plane, while the measured coincidences of the directions are only within 10 deg. The major axis of the platelet is parallel to [010] in the 0. This orientation corresponds to the direction of nearest registry of the lattices.

Jan 1, 1964

By Colin M. Sargent

THE electron diffraction pattern as seen in the electron microscope represents an approximately plane section of the reciprocal lattice. Identifying the zone axis of a diffraction pattern is often laborious for a crystal of low symmetry, especially if several crystal orientations are present. A program has been written in FORTRAN II (Version 2) for the IBM 1620 which will assist in plotting out reciprocal lattice sections. The calculation is performed by choosing a zone axis [uvw] and determining the d spacings and angle between the planes (Ow - v) and (wO - u). (This procedure is varied slightly for zone axes with Miller indices equal to zero.) Cartesian coordinates for the reciprocal lattice points are then calculated for these planes and for (ww— [u + v]). Any reciprocal lattice points within the parallelogram formed by the origin and these three points are then computed. The input and output are best described by use of an example (Monoclinic ZrO2) used in the author's work. Input consists of two cards: 1) The crystal parameters: a, b, c, a, 8, y, e.g., 5.1477, 5.2030, 5.3156, 90.000, 99.380, 90.000. 2) Three numbers, D, E, F, e.g., 5, 3, 3.0710-the first is the limit of the sum (u + v + w) considered; the second limits the absolute value of u, v, and w to (E- 1), e.g., 2, so that zones (221) would be the highest order considered in this example; the third, F, is the required constant, yL. Output is in the format shown in Table I. The reciprocal lattice sections may then be plotted on standard graph paper and compared with the unknown diffraction pattern. (Note that no attempt has been made to deal with systematically absent reflections.) A card deck for the program is available from Colin M. Sargent, ARZ, W-PAFB, Dayton, Ohio, 45433.

Jan 1, 1969

By Grover J. Holt

Open-pit mining on the iron range has been in a stage of transition for several years from the standpoint of mechanization. The most radical change in open-pit mining methods was started in open-pit haulage in 1937 with the departure from the then standard system of locomotive and car transportation and the advent of the heavy duty truck as a replacement. The initial use of trucks was followed shortly by the first installation of a conveyor belt for open-pit ore haulage. The growth of the combination of trucks for gathering units delivering to a conveyor system for transportation out of the pit, has been rapid and this transition appears to have reached a peak in 1949 with locomotives and cars now being used in only a few of the largest open pits. One point which must be considered, if we assume that the maximum equipment change- over point has been reached, is that the largest pits have probably passed their peak of production. Future ore replacement must come from smaller pits wherein the truck conveyor system has done an outstanding job.

Jan 1, 1950

By Walter McKee

WHEN mixed with common cast steel in quantities ranging from 11 to 13 ½ per cent. and properly treated, manganese increases the ductility of the metal and adds greatly to its toughness and resistance to abrasive action, which properties comprise the distinctive characteristics that make manganese steel so valuable for many purposes at the present time. Manganese steel has been manufactured for about 26 years. .It was first made in a small way in England and subsequently produced in the United States in 1892. At present the manganese-steel foundries of this country have an annual capacity of about 60,000 tons and most of the growth has occurred within the past 10 years. In the early days of the industry it was impracticable to make manganese castings weighing over a few thousand pounds, but at present crusher heads, rolling-mill pinions, and similar castings weighing up to 30,000 lb. each are produced, and it does not appear that the limit of weight has been reached by a considerable margin. Manganese steel is similar in analysis to ordinary first-class converter metal except that it is high in carbon and contains from 11 to 13 ½ per cent. of manganese. From one standpoint manganese steel is similar to malleable iron in that the casting as it comes out of the sand is hard and brittle and must be made ductile by a heat-treating process. The heat treatment is an essential part of the process of making manganese-steel castings and must be properly carried out to secure satisfactory results. The necessity for heat treatment limits the thickness of sections which may be made of manganese steel. Originally the annealing depth was comparatively small, but researches carried on during the past few years have resulted in an increase in the thickness of section up to 5 ½ in., which it is possible to treat successfully. Large castings are cored out to a minimum thickness of 5 ½ in., thus not only eliminating some of the internal stresses which are invariably set up in a very thick casting, but also reducing the weight and inertia of the piece, an

Jan 12, 1915

Lieut. Maxwell E. Erdory, now with the Army of Occupation in France, writes as follows: "The 602d Engrs., many of whose officers are members of the Institute, started its active service in France at Avocourt, where we built a road across `No Man's Land.' This road from Avocourt to Montfaucon started us on a career of road building which lasted from Sept. 26 to Nov. 9. The engineer in war has no working hours. Our first job meant 50 hr. continuous work, a layoff of 4 hr. and 18 hr. more. That was our initiation in this war game. "Back in the States we practised building trenches, dugouts, and underground shelters of all sorts. In France we were unfortunate enough to come upon the scene when the so-called open warfare started. That made all the above unnecessary. Roads was the cry and our job was to see that all the artillery got their roads and got over them. "I might mention here that the roads of France, which were in excellent condition except for numerous shell holes, w re one of the leading factors in the rapid termination of the war. "We built a narrow-gage railroad from Romagne to Landre St. George which cost us a few men. At Stenay we did our first bridge building. We built nine bridges across the Meuse, capable of carrying tanks, in 18 hr. The next day the American army crossed these bridges on their way to Virton, Belgium, and the Rhine. " Our course from Virton, Belgium, took us through Longwy, Musson, and Athus, in which towns I inspected the steel plants. In Musson as well as Longwy the Germans had destroyed most of the blast furnaces. This destruction began in August, 1917. In Athus the furnaces were in good condition, the Germans having removed all motors land electrical apparatus, rendering the plant inoperative. I have taken several photos of interest of these plants. "It is but fitting that I say that the engineer in this war has contributed much toward its success but the "Doughboy" is its hero and we engineers one and all say "All hail the Doughboy."

Jan 2, 1919

By Hon. Tasker Oddie

DURING the closing days of the last Congress a resolution was passed, creating the Senate Com-mission of Gold and Silver Inquiry. The resolu-tion charges the Commission with the responsibility to investigate and report to the Congress on Jan. 1, 1924, upon the following subjects: 1. The causes of the continuing decrease in the production of gold and silver. 2. The causes of the depressed condition of the gold and silver industry in the United States. 3. The production, reduction, refining, transportation, mar-keting, sale, and uses of gold and silver in the United States and elsewhere. 4. The effect of the decreased production of gold and silver upon commerce, industry, exchange, and prices. The personnel of the Commission is as follows: Senators Pittman, Sterling, Goodling, Walsh and Oddie. At a meeting on May 8, H. N. Lawrie, a mining engi-neer and economist, was appointed as Assistant to the Commission. The present situation with respect to the gold and silver mining industries is well illustrated by the follow-ing data: The total world production of gold (in dollars) for 1915 was $468,724,918, and for 1921, $329,915,101; as shown by the reports of the U. S. Mint; and for the year 1922, $306,793,000, which is based oh a prelimi-nary estimate; this indicates a decrease of 34.5 per cent. between 1915 and 1922. The total world production of silver (in fine ounces) for 1915 was 178,850,000 oz.; for 1921, 175,268,234 oz., a decrease of 2 per cent.

Jan 6, 1923

By David B. Reger

Exploration for new pools of gas in the Oriskany sand and continued exploitation of areas already known to be productive in that sand were the main features of petroleum activity in West Virginia during 1938. To a considerable extent the exploration program resulted in failure, but the extension of former areas was eminently successful. Throughout the state, in general, less drilling was done than in 1937. According to the West Virginia Department of Mines, only 631 permits to drill were issued, as compared to 1034 in 1937. The account of operations, as reported by trade journals and other sources, shows that 766 wells were drilled, resulting in 131 oil wells with 1609 bbl. of daily production; 484 gas wells with 1,232,216,000 cu. ft. of daily open flow; and 151 dry holes. Several discoveries indicate new pools of oil and gas; and several extensions of old gas pools have been made. In spite of a decreased number of total wells, the figures for new gas and oil are both larger than in 1937. The new oil average is 12.3 bbl. per well per day; the gas average is 2,545,900 cu. ft. per well per day, the ratio of dry holes to completions is 19.71 per cent. No general attempt was made to discover new pools of oil. A continued low price, coupled with reduced takings, combined to make drilling unattractive. The principal oil wells completed, by counties are: Boone, 6; Calhoun, 10; Clay, 7; Gilmer, 5; Kanawha, 5; Lincoln, 7; Pleasants, 13; Ritchie, 32; Roane, 6; Tyler, 7; and Wirt, 14. Production for the year, according to the Oil and Gas Journal, was 3,724,750 barrels. The leading counties in gas, with the number of successful wells in each, are: Boone, 16; Braxton, 13; Cabell, 47; Calhoun, 29; Doddridge, 10; Gilmer, 55; Kanawha, 127; Lincoln, 18; Ritchie, 29; Wayne, 19; and Wetzel, 26. Production for the year is estimated as 150,000,000,000 cubic feet. Pipe-line construction, which was extensive in 1937, was insignificant in 1938. Exploration was not as active as in 1937. Field prices of both oil and gas have severely declined.

Jan 1, 1939

By David B. Reger

Exploration for new pools of gas in the Oriskany sand and continued exploitation of areas already known to be productive in that sand were the main features of petroleum activity in West Virginia during 1938. To a considerable extent the exploration program resulted in failure, but the extension of former areas was eminently successful. Throughout the state, in general, less drilling was done than in 1937. According to the West Virginia Department of Mines, only 631 permits to drill were issued, as compared to 1034 in 1937. The account of operations, as reported by trade journals and other sources, shows that 766 wells were drilled, resulting in 131 oil wells with 1609 bbl. of daily production; 484 gas wells with 1,232,216,000 cu. ft. of daily open flow; and 151 dry holes. Several discoveries indicate new pools of oil and gas; and several extensions of old gas pools have been made. In spite of a decreased number of total wells, the figures for new gas and oil are both larger than in 1937. The new oil average is 12.3 bbl. per well per day; the gas average is 2,545,900 cu. ft. per well per day, the ratio of dry holes to completions is 19.71 per cent. No general attempt was made to discover new pools of oil. A continued low price, coupled with reduced takings, combined to make drilling unattractive. The principal oil wells completed, by counties are: Boone, 6; Calhoun, 10; Clay, 7; Gilmer, 5; Kanawha, 5; Lincoln, 7; Pleasants, 13; Ritchie, 32; Roane, 6; Tyler, 7; and Wirt, 14. Production for the year, according to the Oil and Gas Journal, was 3,724,750 barrels. The leading counties in gas, with the number of successful wells in each, are: Boone, 16; Braxton, 13; Cabell, 47; Calhoun, 29; Doddridge, 10; Gilmer, 55; Kanawha, 127; Lincoln, 18; Ritchie, 29; Wayne, 19; and Wetzel, 26. Production for the year is estimated as 150,000,000,000 cubic feet. Pipe-line construction, which was extensive in 1937, was insignificant in 1938. Exploration was not as active as in 1937. Field prices of both oil and gas have severely declined.

Jan 1, 1939

By C. H. Chou, A. Sauveur

The senior author of this paper has expressed the belief that when gamma iron transforms into alpha iron on reaching the A3 point, each gamma grain does not change bodily into one or more alpha grains but that the alpha phase forms first at the boundaries and along the crystallo-graphic planes of the austenite grains.1 To quote: On cooling through the point As, at about 900° C, iron passes from the gamma condition to a new allotropic form generally designated as alpha. This transformation, however, is not instantaneous. There are good reasons for believing that it begins at the grain boundaries and along the octahedral planes of the crystals and that it progresses until each grain of gamma iron is changed into a grain of alpha iron, the resulting structure being similar to that of gamma iron. Were it possible to retain

Jan 1, 1929

By J. W. Dougherty

THE Hollinger gold mine is in the Porcupine mining division, District of Cochrane, in the northern part of the Province of Ontario. The adjacent town of Timmins, with a population of 25,119, lies 490 miles by railway north of the city of Toronto. GEOLOGY The property is situated on the northwest limb of a major syncline, which pitches northeast at approximately 50°. The principal rocks of the Hollinger area are of pre-Cambrian age and consist of altered, schistose, Keewatin lava flows intruded by stocks of schistose, quartz-feldspar porphyry generally assigned to the Algoman period. The structure of the Keewatin series is extremely complex as a result of close folding and some faulting. The schistosity, trending north 70° east and dipping steeply to the southeast, is most highly developed along a subsidiary anticline in which the major porphyry bodies occur. The ore bodies, which exhibit three principal structures, consist of quartz veins and associated pyritized wall rock. Some lodes are com-posed of en echelon veins, others exhibit a main quartz body with branch-ing stringers and a third consists of a single definite lead. Gold, in a coarse visible form, may be confined to quartz in some ore bodies but in others it is finely divided and is found not only in quartz but also asso-ciated with pyrite in the adjacent wall rock. In many veins the dis-tribution of gold is such that there are several ore sections, separated by areas of low-grade material, in the same vein although its physical appearance remains unchanged.

Jan 1, 1940

Discussion WEDNESDAY AFTERNOON, FEBRUARY 21, 1951 Ralph E. Grim presiding R. E. GRIM, CHAIRMAN-Has anyone a particularly fruitful point to make or question to ask on any of the papers that have been presented at the two sessions held on Monday and one held this morning? GENESIS OF ENDELLITE T. S. LOVERING-I think we are all a little bit embarrassed when we are asked if we have any particularly fruitful point for discussion; I just have a point. I believe that yesterday Bates said that he had found endellite in only hydrothermally altered rocks-he did not find it in sedimentary rocks-but this morning I heard Victor Allen say something about it as the normal product of weathering, and I am confused. My question concerns the genesis of endellite. I want to know whether endellite is found as a normal product of weathering. I understood from the paper by Bates that it was not a product of weathering and in the paper by Victor Allen* endellite was said to be a product of normal weathering. Did I misinterpret these two papers? T. F. BATES-I did not intend to state or imply that endellite is formed only under hydrothermal conditions. We have been studying the North Carolina deposits extensively and I feel that they illustrate very well the result of normal weathering processes acting on pegmatitic material. The resulting clay seems to be largely endellite or halloysite, almost to the exclusion of kaolinite. I may have misled you in the statement I made toward the end of my talk, to the effect that of all the kaolinic clays we have investigated with the electron microscope, we have not yet found halloysite or endellite in samples from clay deposits that are definitely sedimentary in origin. R. E. GRIM, CHAIRMAN-Professor Allen, have you anything to say on the matter of bauxite?

Jan 1, 1952

By W. A. Roper

Since 1950, several papers have been published which have described various methods for studying mobility ratio effects. The methods which have been described for studying mobility ratio effects include X-ray shadowgraph techniques, stepwise potentiometric model procedures, stepwise numerical procedures, gelatin model studies and fluid mapper model studies. The purpose of this paper is to describe a procedure for using a resistance network for studying mobility effects. DESCRIPTION OF APPARATUS The basic unit of the experimental model consisted of a network of 840 resistors fastened to a sheet of black Lucite which was mounted on a wooden frame, Fig. 1. The dimensions of the Lucite sheet were 36 X 36 in. The resistors were fastened to the Lucite sheet at mesh points by means of snaps. The mesh points were arranged in a square pattern, 30 X 30 in., spaced at intervals of l1/2 in. The snap fasteners permitted several resistors to be "stacked" in parallel. By adding additional resistors to the basic unit, the specific resistance on each side of the flood front could be varied. The square network of resistors represented one of four symmetrical elements of a five-spot well pattern. The current input was analogous to an injection well and the current output was analogous to a production well." The power supply was essentially a full wave transformer-rectifier system for converting alternating-current into direct-current. The DC voltage could be varied from 41.43 to 290 v in steps of 41.43 v by selecting the proper outlet jacks. The major components of the power supply were: a Triro power transformer, R 11-A; a dual 5Y3 vacuum tube; two gas filled OD-3 tubes; and a Triplett voltmeter, model 227-1, range 0 to 500 DC v. The voltages at the mesh points were determined with a Keithley electrometer, model 210, No. 185, manufactured by Keithley Instruments, Cleveland, Ohio. A Heathkit vacuum tube volt-

By F. C. Farnham

In this paper it is shown that the vertical component of the earth's magnetic field for the area of the United States can be very closely approximated by assuming it to be the sum of the vertical components of two magnetic fields. The first of these is the field of the centered dipole described by J. Bartels,l the axis of this dipole intersecting the earth's surface at two antipodal points, the one in the Northern Hemisphere being at latitude 78.5°N. and longitude 69°W., and the dipole having such strength that the vertical component of its field at its axis pole is 0.63 oersted. The second field is that due to a second dipole situated halfway between the center of the earth and a point on the earth's surface at latitude 38.5°N., longitude 91.5°W., the axis of this dipole being along this radius, the south pole being toward the surface, and the dipole being of such strength that its field at the point on the surface mentioned above is 0.069 oersted. Using the field computed on this basis, tables of latitude and longitude correction factors were computed and are included in the paper. It is also shown that the secular variation in the earth's magnetic field may be roughly accounted for by assuming it to be due to motion of the second dipole described above. Although there is an error in the equation used for computing the strength of the field due to the second dipole, the distribution of the field computed is very nearly that of the assumed arrangement of dipoles. Subsequent work by the author reveals that minor changes can be made in the location of the second dipole, which will make the computed field fit the observed field even more closely. It has also been found2 that the vertical component of the field may be represented equally well by a purely empiric relationship.

Jan 1, 1940

By F. C. Farnham

In this paper it is shown that the vertical component of the earth's magnetic field for the area of the United States can be very closely approximated by assuming it to be the sum of the vertical components of two magnetic fields. The first of these is the field of the centered dipole described by J. Bartels,l the axis of this dipole intersecting the earth's surface at two antipodal points, the one in the Northern Hemisphere being at latitude 78.5°N. and longitude 69°W., and the dipole having such strength that the vertical component of its field at its axis pole is 0.63 oersted. The second field is that due to a second dipole situated halfway between the center of the earth and a point on the earth's surface at latitude 38.5°N., longitude 91.5°W., the axis of this dipole being along this radius, the south pole being toward the surface, and the dipole being of such strength that its field at the point on the surface mentioned above is 0.069 oersted. Using the field computed on this basis, tables of latitude and longitude correction factors were computed and are included in the paper. It is also shown that the secular variation in the earth's magnetic field may be roughly accounted for by assuming it to be due to motion of the second dipole described above. Although there is an error in the equation used for computing the strength of the field due to the second dipole, the distribution of the field computed is very nearly that of the assumed arrangement of dipoles. Subsequent work by the author reveals that minor changes can be made in the location of the second dipole, which will make the computed field fit the observed field even more closely. It has also been found2 that the vertical component of the field may be represented equally well by a purely empiric relationship.

Jan 1, 1940

By P. A. Beck, L. J. Demer

As reported in a previous publication,' isothermal grain growth in high purity aluminum and in an aluminum alloy with 2 pct magnesium can be adequately described by means of the empirical relation: Here, D is the average gain size after an annealing period 1. The annealing period includes the time for complete recrystal-lization R, and the time for gain growth 1,. D, is the pain size as recrystallized, n is a parameter depending on the temperature and on the material. The effect of 2 pet magnesium in solid solution was to decrease D, and to increase R, A and n at a given temperature. The present work was undertaken in order to investigate the above listed-effects of magnesium in solid solution, as functions of the magnesium content. The work also includes the study of certain anomalous effects observed in the recrystal-lization and grain growth of the 2 pct magnesium alloy at 350°C. Experimental Procedure The method of producing the ingots used in this work was described in detail1 and need not be reproduced here. The materials used were high purity aluminum, furnished by the Aluminum Co. of America, of lot analysis shown in Table r and magnesium from a high purity distilled stock of magnesium crystals. Table i—Lot Analysis of High Purity Aluminum Per CeNt Si.................................... 0.00~ Fe.................................... 0.002 Cu................................... 0.002 Mg................................... 0.003 Mn................................... o. oox Ingots were prepared for a series of binary aluminum-magnesium alloys of increasing alloy content. The numbers used to designate these ingots and their magnesium contents by chemical analysis are given in Table 2. Table 2—Ingot Numbers and Magnesium Contents Ingot Number Pct oa Magnesium aI 2.05 22 1.80 24 0.12 26 0 02s The analyses showed no difference in composition between the top and the bottom of the ingots. Spectrographic analysis of the ingots for elements other than magnesium showed, within the limits of accuracy of the method, no increase in impurities over the amounts given in the lot analysis for the high purity aluminum in Table I. Careful microscopic study of ingot 21 in the as-cast condition, at magnifications up to I 500X, revealed a cer-

Jan 1, 1949

By R. S. Shoemaker, F. W. McQuiston

CARLIN GOLD MINING COMPANY 1974 Operating Data to October MINE LOCATION: 40 miles from Elko, Nevada ORE DESCRIPTION: Gold with minor amounts of mercury occurring in siltstone and carboniferous limey shales. TYPE OF MINE: Open pit ORE HAULAGE TO MILL: By trucks up to a distance of 12 mi1es MILLING CAPACITY: 2500 tons per day ORE GRADE: 0.20 oz per ton oxide ore 0.25 oz per ton carbon type ore PRODUCTS: Gold bullion 993 fineness, by product quicksilver RECOVERIES: Oxide ore 887'0 Carbon ore 83% POWER FOR GRINDING: 7 Kwh/T POWER, other than grinding: 14 Kwh/T WATER SUPPLY: Pumped from wells 2- 112 miles through 13,000 ft of 8" buried pipe 6 ft underground. Consumption 0.60 tons of new water per ton of mill feed. TAILINGS: By 10" woodstave pipe a distance of 2500 ft to mine waste filled dam. RUNNING TIME: 10 ft x 10 ft mill on oxide ore, 98% 7 ft x 8 ft mill on carbon ore, 937'0 Principal causes of lost time, power outages and problems of feeding gaseous chlorine to carbon ore agitators. LABOR, TONSIMAN SHIFT: See detailed data sheet ILL BUILDING DESCRIPTION: Framed structural steel with sandwich type walls of marine plywood, then packaged pre - fabricated insulation and outer sheeting of galvanized corrugated steel.

Jan 1, 1975

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) The following members registered at Institute headquarters during the month of April: J. C. Ralston, Spokane, Wash. E. P. Ross, Johnson City, Tenn. C. H. James, London, Eng. F. L. Garrison, Philadelphia, Pa. E. H. Benjamin, Oakland, Cal. A. Radcliffe, Copiapo, Chile. W. H. Shockley, Palo Alto, Cal. S. S. Wyer, Columbus, Ohio. A. C. Mauney, Salisbury, N. C. W. B. Kunhardt, Reading, Pa. A. W. Newberry, Los Angeles, Cal. W. E. Saunders, Philadelphia, Pa.

Jan 5, 1913

MINING; SOLUTION U.S. 4,066,297 - In the solution mining of uranium from an underground deposit of uranium ore using an alkaline leaching solution, precipitation of alkali metal salts is avoided by maintaining the Injected leach solution of an alkaline carbonate or bicarbonate and an oxidant undersaturated with respect to carbonates Undersaturation is effected by use of a water softening unit or by bleeding a portion of the recycled alkallne leach solution. A P. Spence, assigned to Atlantic Richfield Co Jan. 3, 1978 4 pp. (299-4). Filed: 6-1-76 (69 1,344)

Jan 1, 1979