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By H. M. Morse

Mississippi, during the year 1941, experienced the greatest diversity of oil activity since the beginning of oil interest in the state—core tests for exploration, core tests for sulphur, continued drilling at Tinsley for production, and wildcatting, which brought to light two new oil fields and two new salt domes. There were 45 wildcat wells drilled in 1941, which showed greater results and findings geologically than the 85 drilled in 1940. Tinsley Oil Field (Yazoo County).—The Tinsley oil field, with its boundaries fairly well defined now, is 8 miles long and 3 miles wide at its widest point. During the past year 213 producing wells were completed, which brought the total number of producers in the field by the end of 1941 to 325 wells. Seven producing sands have been logged, with a total average thickness of 30 ft. of oil sand. The producing formations are the Selma, Eutaw and Tuscaloosa. The average total depth of the wells is 5012 ft. The average gravity of the oil is 35.4°. Production for 1941 was approximately 15,500,000 bbl. of oil. Vaughan-Pickens Oil Field (Yazoo County).—At the end of 1941 only three wells were Producing in this field, the fourth having been abandoned. The total production for the field for the year was approximately 250,000 bbl. of oil. The producing sand is the Wilburn, in the Eutaw formation. Cary Field (Sharkey County).—The British American Oil Producing Co. completed, on Sept. I, 1941, its F. B. Houston No. A-I well, sec. 23, T. 11 N., R. 7 W. It is

Jan 1, 1942

By J. W. Downey, S. T. Zegler

A study has been made of the occurrence of Phases having the Cr30-type structure in ternary alloys having the general composition where B cept for iron and copper all the B components are known to form binary compounds having the type structure. The occurrence of the struc-ture type in the ternary alloys was investigated using optical and X-ray metallography. The results indicate that iron can replace virtually none of the cobalt in at 900°C, but substitutes for nickel in up to the approximate composition tually insoluble in V3Ni and 2) and exhibit complete solubility. At 100 nickel can be substituted for cobalt in VSCo up to the composition solubility; and 3) in the system , two solid solutions having the type structure occur. At the same temperature, 1000°C, V3Si exhibits limited solubility for V3Co but is completely mis-cible with V3Ga. Lattice parameters have been determined for all the binary and ternary phases. The solid solutions are discussed in terms of the atomic size and electronic factors which are thought to influence the occurrence of Cr30-type phases. The binary compounds V3Co and V3Ni were found to form peritectoidally from o phases and a vanadium, the former compound at a temperature between 1000" and 1050°C, the latter between 800°and 900°C. The substitutions of nickel and rhodium for cobalt in V3Co were determined not to raise the superconducting transition of VSCo to a temperature as high as 2°K. The occurrence and stability of binary intermediate phases having the Cr30- or A15-type structure (space group o;, Pm3n) have been discussed in several recent papers . Vanadium forms the struc -ture at or near V3B stoichiometry with all the mem -bers of the cobalt and nickel groups in the periodic table and also with Au, Ga, Si, Ge, Sn, P, As, and Sb. This paper describes a survey of the occurrence of the CrsO-type structure in ternary alloys having the general composition V3(B, B') where B and B' are Fe, Co, Ni, Cu, Rh, Ir, Si, and Ga. The purpose of the survey was to clarify the connection between the position of the B partner in the periodic table and its CrsO-type phase-forming tenden~y.~,~ The survey is part of a broader program concerned with the influence of B-partner substitutions on the superconducting transition temperatures of CrsO-type compounds. The transition temperatures, Tc, of some of the ternary Cr,O-type phases found in the survey are also discussed in this paper. EXPERIMENTAL PROCEDURE The alloys were prepared by arc-melting in an A-He atmosphere and were in the form of buttons, weighing approximately 3 g. The metals used in their preparation were received from commercial sources and were in all cases 99.9+ pct pure. The vanadium was spectrochemically pure except for 800 ppm of Si, 200 ppm of Fe, and 200 ppm of Al. For study of each pseudobinary system at least seven alloys were prepared having the general compositions case of alloys containing gallium, melting losses were small, usually less than 0.3 pct of the total weight of the metals charged for melting. Melting losses were somewhat greater for gallium alloys, ranging in general from 0.9 to 5.0 pct. Ternary V-Si-Ga alloys were chemically analyzed and the results are given in Table I. The analyses show most alloys to be within 2 at. pct of the intended composition. Throughout the balance of the paper the intended compositions are used in discussing the alloys. The cast buttons were annealed within evacuated quartz capsules for times ranging from 3 to 6 weeks at temperatures between 800" and 1000°C and water-quenched. The phases present in the annealed and quenched alloys were identified by optical and X-ray metallography. X-ray diffraction photograms were made with powders prepared from the bulk specimens, by the use of a 114.6-mm-diam powder camera with copper irradiation. The lattice parameter of CrsO-type phases and their standard errors

Jan 1, 1963

By McHenry Mosier

MeRcuRy is one of the strategic metals of which the supply has been raised from critical uncertainty to more than enough for essential demands. Work by the Bureau of Mines has contributed substantially to increased production of mercury in the United States and to consequent accumulation of Government stocks. Other contributing factors have been higher prices for mercury and Government loans to operators. The Bureau has undertaken 13 exploration projects, 10 of which have been completed. This work has comprised 28,376 ft. of several types of drilling and 23,798 lin. ft. of surface trenching, and has indicated commercial ore containing 34,800 flasks of mercury and marginal ore containing 26,200 flasks, a total of 61,000 flasks; equivalent, respectively, to domestic production for 8 months, 6 months, and 14 months. As Government stocks are now adequate, domestic production (currently at the rate of 50,000 flasks per year) is gradually being curtailed through Government control of labor and operating supplies. Introduction Mercury was one of the seven metals designated as strategic by the Army and Navy Munitions Board in 1939, when Congress appropriated funds for the investigation of domestic sources of supply of war minerals. The Bureau of Mines immediately started a limited search for strategic minerals, but the first mercury project was not begun until December 1940. The U. S. Geological Survey assisted in the search for cinnabar by contributing information on domestic mercury deposits, preparing maps, and making geological studies of exploration projects. The present high rate of production of mercury in the United States was encouraged by the increase in price to $196 per flask at New York (Fig. I) and Government loans to operators for mine development and plant construction. The Bureau of Mines has issued, for restricted distribution subject to wartime controls, 13 War Minerals Reports on individual mercury deposits (listed in appendix A). In March 1942 it also published a Progress Report of the Metallurgical Division, R. I. 3627, Cinnabar-reduction Plants of the Southwestern Arkansas Quicksilver District. Uses of Mercury Mercury and its compounds have more than 3000 uses. Its principal use is as a catalyst in the manufacture of gases for chemical warfare; the next largest is in pharmaceuticals. Mercury is essential also for: (I) certain electrical apparatus, (2) industrial control instruments at many war plants, (3) munitions, including blasting caps, (4) insecticides in agriculture, (5) antifouling paint for ship bottoms, (6) dental preparations, (7) general laboratory use, and (8) amalgamation of free-milling gold ores.

Jan 1, 1949

By McHenry Mosier

MeRcuRy is one of the strategic metals of which the supply has been raised from critical uncertainty to more than enough for essential demands. Work by the Bureau of Mines has contributed substantially to increased production of mercury in the United States and to consequent accumulation of Government stocks. Other contributing factors have been higher prices for mercury and Government loans to operators. The Bureau has undertaken 13 exploration projects, 10 of which have been completed. This work has comprised 28,376 ft. of several types of drilling and 23,798 lin. ft. of surface trenching, and has indicated commercial ore containing 34,800 flasks of mercury and marginal ore containing 26,200 flasks, a total of 61,000 flasks; equivalent, respectively, to domestic production for 8 months, 6 months, and 14 months. As Government stocks are now adequate, domestic production (currently at the rate of 50,000 flasks per year) is gradually being curtailed through Government control of labor and operating supplies. Introduction Mercury was one of the seven metals designated as strategic by the Army and Navy Munitions Board in 1939, when Congress appropriated funds for the investigation of domestic sources of supply of war minerals. The Bureau of Mines immediately started a limited search for strategic minerals, but the first mercury project was not begun until December 1940. The U. S. Geological Survey assisted in the search for cinnabar by contributing information on domestic mercury deposits, preparing maps, and making geological studies of exploration projects. The present high rate of production of mercury in the United States was encouraged by the increase in price to $196 per flask at New York (Fig. I) and Government loans to operators for mine development and plant construction. The Bureau of Mines has issued, for restricted distribution subject to wartime controls, 13 War Minerals Reports on individual mercury deposits (listed in appendix A). In March 1942 it also published a Progress Report of the Metallurgical Division, R. I. 3627, Cinnabar-reduction Plants of the Southwestern Arkansas Quicksilver District. Uses of Mercury Mercury and its compounds have more than 3000 uses. Its principal use is as a catalyst in the manufacture of gases for chemical warfare; the next largest is in pharmaceuticals. Mercury is essential also for: (I) certain electrical apparatus, (2) industrial control instruments at many war plants, (3) munitions, including blasting caps, (4) insecticides in agriculture, (5) antifouling paint for ship bottoms, (6) dental preparations, (7) general laboratory use, and (8) amalgamation of free-milling gold ores.

Jan 1, 1949

The Committee on Nominations begs to submit the following names as its nominees for the respective offices indicated: For President, SIDNEY J. JENNINGS, New York. For Vice-Presidents, WALTER H. ALDRIDGE, New York; MARK L. REQUA, San Francisco. For Directors, J. E. JOHNSON, JR., New York; ALLEN H. ROGERS, Boston; HOWARD N. EAVENSON, West Virginia; ROBERT M. RAYMOND New York; WILLET G. MILLER, Canada.

Jan 12, 1916

By Hallan N. Marsh, Bruce H. Robinson

It is now generally recognized that to secure the greatest ultimate recovery of petroleum from a field it is necessary to maintain at all times the lowest possible ratio of gas to oil production. The numerous ways of securing low ratios are not so generally understood or practiced. To many operators, reduction of gas-oil ratio simply means "beaning back" wells, with resultant reduced production rate. This postponement of production is often considered and spoken of as "lost" production, with the result that control of gas-oil ratio is in disfavor with some operators. Various methods are herein discussed by which gas-oil ratio may be reduced, some of which invoLve no curtailment of current production, while others are accompanied by an actual increase of daily production. It is further shown that in cases where rate of production is reduced to conserve gas, the indicated ultimate recovery is generally increased. Principles involved are discussed, and conclusions are illustrated by data from the operation of wells. General Principles The rate and ratio in which oil and gas enter a well are solely dependent, so far as the operation of that well is concerned, upon the pressures maintained in the well opposite the producing strata at various times and at various depths. The method of getting the oil out of the hole, whether by natural flow, gas-lift, or pumping, has no effect upon either rate of production or ultimate recovery except through its effect upon pressures. Oil apparently enters wells according to some such equation as the following: R = KC(Pf - Pw)n Where R = rate of production. K = well coefficient, depending upon thickness of sand, and size and number of pores in the sand. C = fluid coefficient, depending upon viscosity, surface tension, etc.

Jan 1, 1929

By M. Shelef, A. W. Fletcher

The effect of alkali sulfates in promoting the sul-fation of nickel and copper in a bulk sulfide flota -tion concentrate by fluidized bed roasting has been studied in the laboratory, and it was shown that the various alkali sulfates promote sulfation to approximately the same extent. The sulfation of a mixture of synthetically prepared iron and nickel oxide and of nickel ferrite has also been studied. Nickel sulfation was promoted by high ratios of Fe:Ni and by the presence of sodium sulfate. THE work described in this paper was a continuation of earlier studies into the role of alkali sulfates in promoting the sulfation roasting of nickel sulfides1,2 in an endeavor to determine how the system was affected by the presence of compounds of iron and copper. The earlier work1 showed that, in the sulfation of NiO at 680°C, the reaction was limited by the formation of an impermeable film of nickel sulfate on the oxide surface. The relative effect of the various alkali sulfates in promoting nickel sulfation varied in the order: Li > Na >Cs > Rb > K A study of alkali sulfate/ nickel sulfate interactions at high temperatures showed that the promoting action was due to the fact that the nickel sulfate product layer sintered and agglomerated only when the more active additives were present. This resulted in the formation of discontinuities in the nickel sulfate layer so that diffusion of the sulfating gases to the NiO surface was no longer impeded and the reaction could proceed to completion. A similar explanation was used for the observation that sodium and lithium sulfates promote the oxidation of NiS to NiO at temperatures below 750°C since small amounts of nickel sulfate were formed during oxidation.2 It was of interest to study the effect of alkali sulfates on the sulfate roasting of a sulfide flotation concentrate which is typical of material treated commercially. In order to control temperature it is essential to roast sulfides in a fluidized bed and this technique was therefore used, although the batchwise operation of a small-scale laboratory reactor does not reproduce all conditions which prevail in full-scale continuous plant. The results obtained are therefore only comparative, and cannot be used for predicting the optimum conditions for metal extraction. The sulfation of synthetically prepared mixed oxides of nickel + copper and nickel + iron and of nickel ferrite was also studied to evaluate the relative effects of alkali sulfates with more complex systems. SULFATION ROASTING OF A SULFIDE FLOTATION CONCENTRATE The bulk sulfide flotation concentrate used in this work contained 7.92 pct Ni, 1.74 pct Cu, 35.66 pct Fe, and 31.28 pct S. The sulfide minerals present in order of abundance were pyrrhotite FeS, pyrite FeS2, pentlandite (FeNi)S, and chalcopyrite CuFeS2. Two samples described as coarse and fine were used. The coarse sample, which was a flotation concentrate (58 pct plus 300 mesh), was ground to 100 pct minus 350 mesh to produce the fine sample. Before roasting, the sample of sulfide concentrate was agglomerated by wetting witli a solution of the alkali sulfate (or water), thoroughly mixing, and drying at 110°C. This gave a cake which was gently crushed and screened, the -18 +100 mesh fraction being used for fluidized bed roasting. A similar-size fraction had been used by the authors in pilot plant work with a 4-in.-diam fluidized bed reactor.' In this work it was found that the molar ratio of additive to the total iron + nickel + copper content of the sulfide sample should be adjusted to a value of approximately 0.06, as this was the optimum amount necessary for nickel sulfation. Experimental. The fluidized bed reactor consisted of a quartz tube approximately 60 cm long and 30 mm in diameter resting in a vertical tube furnace. The sulfide bed (30 g) was supported on a bed of -4 +12 mesh quartz particles 3 cm high, which rested on a sintered quartz disc welded to the tube. The temperature of the furnace was controlled with a variable transformer to give a final bed temperature of 680°C. The bed was fluidized with air or mixtures of air + 10 pct v/v SO2, at a total apparent gas velocity of 60 to 65 cm per sec at 680°C. The SO2 was introduced into the fluidizing air stream only when the oxidation of the sulfides was completed. At the end of the roasting period the calcine was leached with boiling water and the

Jan 1, 1964

[RALPH ADAIR Ore Dressing Consultant Bull Mtn. Rd., Asheville, N. C. Phone 4-1693 JAMES A. BARR Consulting Engineer Mt. Pleasant, Tennessee Washington, D.C. BEHRE DOLBEAR & COMPANY Consulting Mining Engineers and Geologists 11 Broadway New York 4. N. Y. I. R. BERENT Engineering Consultants and Contractors Mineral Exploration, Mine Evaluation, Mine Designs and Mine Management 156, Ataturk Bulvarl-Ankara, Turkey BLANDFORD C. BURGESS Registered Professional Engineer Mining Consultant Monticello, Georgia GLENVILLE A. COLLINS Mining Engineer Uranium examinations Cable "Coins" 210 La Arcade Bids. Santa Barbara, Calif.]

Jan 1, 1952

By H. Foster Bain

THERE has never been a great civilized nation which did not have a mining industry; civilization cannot flourish without metal mining. Without tools we can have none of the 'industries that are the foundation of civilization and without metal mining we cannot produce the material of which tools are made. Therefore, if we have no metal mining we have no metals, no tools, no civilization. An example to illustrate this may be drawn from a recent article in the Saturday Evening Post which described the run-down condition of modern Athens. Athens is nothing but a busted mining camp! In its palmy days the Greeks so applied the leasing system to the silver mines of Laurium that the royalties, paid the expenses of government and instead of a tax bill the inhabitants received a pay check. The Persians came over to capture these mines but the Greek navy was built to defend them. When the silver mines played out, Greek civilization declined.. Our mining must continue if our civilization is to continue.

Jan 1, 1921

[RALPH ADAIR Ore Dressing Consultant Bull Mtn. Rd., Asheville, N. C. Phone 4-1693 JAMES A. BARR Consulting Engineer Mt. Pleasant, Tennessee Washington, D.C. BEHRE DOLBEAR & COMPANY Consulting Mining Engineers and Geologists 11 Broadway New York 4, N. Y. I. R. BERENT Engineering Consultants and Contractors Mineral Exploration, Mine Evaluation, Mine Designs, and Mine Management 156, Ataturk Bulvari-Ankara, Turkey BLANDFORD C. BURGESS Registered Professional Engineer Mining Consultant Monticello, Georgia GLENVILLE A. COLLINS Mining Engineer Uranium examinations Cable "Coins" 210 La Arcada Bldg. Santa Barbara, Calif.]

Jan 1, 1952

By M. van Swaay, C. E. Birchenall

A. S. lBrling (Johnson, Matthey & Co. Ltd., Laboratories)— Because of its initial emphasis upon the production of membranes by powder metallurgy and by normal casting and rolling techniques, this paper is of considerable interest to those concerned with the design and application of industrial diffusion units. As the subsequent performances of the three grades of palladium were not compared in detail, it can perhaps be concluded that specific permeabilities were very similar. A short table in which the absolute diffusion rates obtained by the Authors with their three grades of palladium were compared with those of other investigators18-25 would, however, have been of particular value in view of the very variable results obtained with this membrane material. The Authors state early in the paper that the permeability of the thoriated samples decreased in much the same way as that of the nonthoriated samples. Later, they emphasize that sintered palladium without thoria was very susceptible to poisoning and did not respond as well as the other materials to the decontamination treatment. These results, which suggest that sintered membranes are less effective than those produced by normal methods, have considerable industrial implications, and amplified experimental details would be very welcome. The results of the Authors differ in one important respect from those of other investigators. Thus, no "bleeding" was required to maintain a constant rate of diffusion, although Davis, Darling, and De Rosset found this to be necessary. Davisz3 found that "bleeding" was necessary even when the hydrogen had already been purified by diffusion through a palladium tube, and it would be of value to know the purity of the gas stream emerging from the purification train shown on Fig. 1 of the Authors' paper. The Authors show that diffusion rates varied according to the square root of the pressure difference providing that the palladium membrane was not contaminated in any way. This finding is in agreement with the results of those workers2,18,19,23,24 who diffused their hydrogen through the membrane into a partly or completely evacuated system.Those workers who did not find this square-root law dependence did not have a partial vacuum on the downstream-side of the membrane.'' The difference between the two experimental con- ditions appears to be significant, as the absolute diffusion rates per sq cm of diffusion area are lower when the square-root law dependence is not observed. While the effect could be attributable to poisoning of the membrane it is conceivable that a positive pressure on the downstream side of the membrane might influence the mechanism of diffusion. In view of the capricious behavior of palladium, factors of this type, which are likely to influence its industrial significance, should be carefully considered. M. van Swaay and C. E. Birchenall (authors' 9-eply) — Our Eq. 191 may be compared with several others for hydrogen diffusion in palladium: D = 5.95 x exp (-5770/1)' D = 3.55 x 10"3 exp (-5550/)' D = 4.3 x 10"3 exp (-5620/1')' Other values are given in the literature, but in many cases surface poisoning may have affected the results. No analysis was performed on the hydrogen gas stream after purification. It should be noted that the presence of liquid nitrogen traps near the heated membranes may have set up convection currents and provided the equivalent of "bleeding." The question of whether a partial vacuum existed on the downstream side of the membrane is not clear. Does it imply that there is something unique about the permeability measured near one atmosphere pressure? We do not believe that there is. When square root pressure dependence is not observed, diffusion rates are not measured. Is "absolute diffusion rate per sq. cm. of diffusion area" equivalent to permeability? The terminology is new to us. In any case we doubt very much that pressures of the order of several atmospheres can affect the mechanism of diffusion.

Jan 1, 1962

[TWEEDY, A. M., and VOGEL, FELIX A.: The Briquetting of Flue Dust in the United States by the Schumacher Process, XLVII, [viii], 338. TWEEDY, GEORGE A., and BEALS, ROGER L.: Cyanide-Plant and Practice at the Minas del Tajo, Rosan'o, Sinaha, Mez., XLI, [xl], 324. Twin Falls plant, Peninsular Power Co., LI, 298. Twins, deformation lies in manganese steel, LI, 882. 2,000-Ton Leaching Plant at Anaconda (LAIST and ALDRICH) (With Discussion), LV, [xxiii], 866.]

Jan 1, 1918

By F. M. Waring

produced when zinc is substituted for a certain amount of tin are decidedly unsatisfactory. The substitution of aluminum for tin is entirely impractical, and such castings are worthless. This does not, however, exhaust all the possibilities of substituting other metals for tin in the copper-tin-lead alloys, but it is my opinion that the substitution of any other metals, in those alloys, can be made only by sacrificing the quality of the alloy. The possibility of substituting alloys of an entirely different type presents an attractive field for research. The copper-tin-lead alloy has attained its position as the most desirable bronze bearing alloy, but this does not mean that some other alloy may not be found which may give equally good or better results. In the search for such a substitute alloy it should be borne in mind that a bearing metal should possess the following properties: (1) It should be sufficiently rigid to support the load or resist the impact, but yet not so brittle that it will easily crack. (2) It should have as great a yielding or plastic nature as is consistent with its ability to support the load or resist the impact without deformation of the bearing as a whole. (3) The ideal structure combines a hard matrix to support the load and a softer metal or alloy contained within such matrix, to permit the bearing surface to adjust itself to irregularities of service. (4) It should be easy to handle in the foundry and machine shop. (5) It should be capable of being remelted without deterioration. (6) For use in babbitt-lined bearings, it should be capable of being tinned, so that the babbitt can be applied thereto. (7) It should have good heat conductivity in order to dissipate the heat generated by friction. Pennsylvania Railroad Anti-friction and Bell Metals F. M. Waring," Altoona, Pa.—Thc necessity for conserving tin has recently been very forcibly brought to the attention of all consumers, and efforts are now being made to reduce the tin content in certain alloys or to substitute other alloys not containing tin. The approximate composition of the non-ferrous alloys in general use on the Pennsylvania Railroad are given in the accompanying table. Phosphor bronze is used principally for rod bushings, main-rod brasses, and crosshead shoes. Ex. B bronze is used to a small extent for backs of car and coach bearings, but the majority of these are now made of the car-journal bronze, which contains, on the average, about 5 per cent. tin.

Jan 1, 1919

Jan 1, 1888

By G. H. Alani, H. T. Kennedy

One of the major difficulties in predicting the performance of oil reservoirs from their early pressure history lies in the uncertainty of estimating the volume of the liquid hydrocarbons contained in them. As a first step in filling this need, an equation was developed to determine the Inolal liquid volume of pure hydrocarbons over a wide range of temperature and pressure. The second step consisted of adapting the equation to apply to mixtures, with the heary hydrocarbons expressed as c The equatious are similar in form to van der Waals equation. hut the constants a and b tire considered as furnctions of temperature. In addition to the gas constant R, there are four constants characteristic of each hydro- When comptired with experimental values jound in the literal the. the average absolute deviation in the calculated molal volumes is found to be a Maximum of 0.33 per -cem for any of the pure liquid hydrocarbons studied. This maximum deviation was that found when comparing the calculated and observed values over a temperature range of 86° to 482°F and a pressure range from the bubbl-point ro 10,000 psis. The equations expressing the correlation for. mixrurrc were developed from 647 experimental measure-rilents of volume on 47 bouom-hole samples covering ; temperature range of 72" to 250°F and a pressure znge from bubble-point ro 5,000 psig. The average absotute deviation was found to he 1.6 per cent with the maximum for any measurement of 4.9 per cent. INTRODUCTION Accuratc information of the pressure-volume-temper-iiture behavior of hydrocarbon liquids is of considerable importance in the field of both applied and theoretical science and, especially, in the solution of petroleum reservoir engineering problems. These PVT relationships can be expressed graphically, in tabular form or as equations of state. Equations of state for gases have been developed based on the ratio of pressure, temperature and volume to the pressure, temperature and volume at the critical points of the hydrocarbons. These equations have been successful in yielding values fairly accurate for reservoir engineering purposes. For liquids, however, relations of this type are more complex and have not yielded useful results. The composition of reservoir liquids is normally expressed in terms of the moles of hydrocarbons C,? C,. C,. elc, per mole of mixture. The composition must include the fraction of a mixture such as C,,, which cannot be separated with reasonable time and effort into specific hydrocarbons. Although there are several equations of state having variable degrees of accuracy applicable to pure liquid hydrocarbons, none includes a means for estimating the volume of mixtures as a function of temperature. pressure and composition expressed in this manner.

By S. D. Dahlgren

ORDERED G.P. zones having the cesium chloride structure were found to exist in the bcc iron-rich grains of an Fe-Au-Cu alloy that had been supersaturated with approximately equal atomic percentages of gold and copper, and aged at 400° and 350°C. Streaks and superlattice spots in electron diffraction patterns revealed the presence of the ordered zones in the aged material. The ordered Ll2 structure is commonly found for precipitates in fcc metals (e.g., Ni3A1 in nickelL7') but it is uncommon to find precipitates in bcc metals having the cesium chloride structure. The formation of the G.P. zones caused age hardening of the grains. Samples containing 3.8 at. pct each of gold and copper (with the remainder being iron) were annealed at 95@ or 1125°C in quartz capsules and were quenched by breaking the capsules under water. X-ray diffraction patterns revealed two solid solutions in the quenched samples. One solid solution was bcc and the other was fcc. The microstructure consisted of iron-rich grains of 0.3 mm diam surrounded by a yellow gold-copper-rich grain boundary network. The Au-Cu phase diagram %hows continuous solid solubility of gold and copper with ordered phases forming below 410°C. None of the ordered Au-Cu phases have the cesium chloride structure. Both Fe-Au and Fe-Cu phase diagrams3 show extended miscibility gaps and only terminal solid-solution phases. Consequently, it is reasonably certain the iron-rich grains consisted of an a-phase terminal solid solution, and the grain boundary network consisted of a gold-copper-rich terminal solid solution. Lattice parameters of the quenched solid solutions were consistent with the suggestion that the quenched phases were terminal solutions. The lattice parameter of the bcc phase (2.879A) obtained upon quenching from 950°C was higher than that (2.866A) for pure iron. The fcc phase in this sample had a lower lattice parameter than that for a 50 at. pct Au and 50 at. pci Cu solid solution, i.e., 3.866 compared to 3.877A. The lattice parameter for the 50 pct Au and 50 pct Cu solid solution was interpolated from data for Cu-Au solid solutions.4 More gold and copper were soluble in iron at 1125°C than at 950°C as indicated by a 0.012A increase in the bcc lattice parameter for a sample quenched from 1125°C. After the alloy had been quenched from 950° and 1125°C, the bcc lattice parameters were 2.879 and 2.891A1 respectively G.P. zones having the cesium chloride structure-which formed during low-temperature aging—were detected by electron diffraction and observed with electron transmission microscopy. In Fig. 1, the asymmetrical streaks parallel to ( 100) directions indicate that platelike G.P. zones had formed parallel to (100) planes of the matrix. The direction of streak asymmetry shows that the bcc unit cell of the G.P. zones was larger than the bcc cell of the matrix. The ordered cesium chloride structure is indicated by low-intensity superlattice spots at 010 positions which are nonallowed for bcc structures. The superlattice spots are streaked; therefore they are from the G.P. zones and are not caused by rel-rod effects of a thin matrix phase. The appearance and size of the zones observed in electron transmission microscopy and the appearance of the asymmetrical streaks in the electron diffraction patterns for the Fe-Au-Cu alloy were the same as those observed for a similarly treated Fe-Au alloy.' Ordered G.P. zones were detected also for an Fe-Au-Cu sample aged only at 400°C. The production of the ordered cesium chloride structure zones by low-temperature aging of super-

Jan 1, 1968

By Strathmore R. B. Cooke, Marcus Digre

That calcium will activate quartz for flotation with anionic collectors such as soaps has been known for a number of years,12'3 and the method has been applied to the concentration of various iron ores4 5 6 as well as to other materials. Clemmer gives the permissible pH range for the activation of quartz by calcium as between 9.5 and 12.5 with an optimum value of 11.0, and Hertzog7 has determined the calcium abstraction of iron ores and of Ottawa sand, but otherwise little quantitative data are available. The purpose of the present investigation was to determine those conditions under which dilute solutions of calcium chloride will activate quartz for anionic flotation and to determine the amount of calcium ion adsorbed by quartz. Those variables, the influence of which was primary, such as calcium, sodium, and hydrogen ion concentrations, were studied. Other factors which influenced the results are discussed in the description of the experiments. Three different experimental methods were used to determine the activation of the quartz. The first method was to treat a sample of ground, deslimed quartz with solutions of calcium chloride and sodium hydroxide, and to determine the calcium adsorbed by chemical analysis of the solution. Advantages are that a direct value for the amount of calcium adsorbed is obtained, and introduction of a collector which may affect the adsorption is avoided. The difficulty is to determine the extremely small differences in the calcium concentrations before and after the abstraction. The second method was to determine the activation of the quartz by observing the contact angle obtained on pressing an air bubble against the polished surface of a piece of quartz immersed in a solution of calcium chloride, sodium hydroxide, and sodium oleate. This is the well-known "contact angle" method. The third method was to determine those conditions under which an air bubble will pick up quartz particles immersed in a solution of the desired reagents. Disadvantages common to the sec- ond and third methods are that introduction of a collector is necessary to obtain bubble contact with the mineral; very small quantities of contaminant can give erroneous results; and no information is obtainable concerning the amount of calcium adsorbed. Advantages are that tedious analyses, which at best give approximate results, are avoided, and the conditions, especially for the third method, closely simulate those of actual flotation. Although the most consistent results were obtained with the third method, this paper describes the techniques used and the results obtained from each of the three methods. Distilled water and analytical grade reagents were used throughout except where otherwise stated. Between tests all glass articles were cleaned with a chromic-sulphuric acid mixture and sodium hydroxide. Abstraction Method The raw material for the tests was Ottawa sand sized between 14 and 28 mesh. Batches of 500 g of this sand were dry ground for 1 hr in an Abbe porcelain mill with 2700 g of quartz pebbles. The batches were split down to samples weighing approximately 30 g, and the weight of each sample was adjusted to exactly this value.

Jan 1, 1950

By J. L. Wyatt

THE strain sensitivity, K, a property of metals defined as the unit change in electrical resistance per unit strain, was measured for commercial purity titanium wire to determine its usefulness as a strain gage material. A Kelvin double bridge, accurate to 0.000001 ohm, was used to make measurements from 0 to 1 pct total strain. A positive value of 0.17 for K was found. This compares with 2.15 for constantan and 3.5 for cold-worked invar, two of the more common strain gage materials. The effect of temperature also was determined. It was found that a change in temperature of 30°F caused the same resistance change as 1 pct strain. It is therefore concluded that titanium would have utility as a strain gage only if the thermal fluctuations in the specimen could be controlled to a high degree and in applications of very large total strain.

Jan 1, 1953

By Jack Haptonstall

INTRODUCTION The mines of western central Mexico historically contributed a profusion of gold and silver for the treasury of Spain and later provided sources for financing the Mexican War for Independence and the Mexican Revolution. The western coastal and barranca (cliff) tribes were hunters and extremely hostile, and the Spaniards were not able to penetrate many of the rich districts of their rugged homeland until the mid-1700's. This was more than 200 years after Cortez began the Inquisition by defeating the Aztecs and their allies in a decisive battle in the great city of Tenochtitlan (present day Mexico City). The Spaniards had a voracious appetite for silver and gold, and it was inevitable that they would finally subdue the natives and commence mining activities. Described in this paper are some of the precious metal mining activities in the southern half of the State of Sinaloa and the western half of the State of Durango (Figure l), and specifically those mining activities in the area controlled by the company with which the author was associated for 14 years, Minas de San Luis, S. A. de C. V., the parent company of which is now Industrias Luis Min, S. A. GENERAL DESCRIPTION Geography, Logistics and Climate The most spectacular of the physiographic provinces, the western Sierra Madre Occidental is the cliff or "barranca" province, the

Jan 1, 1983

[RALPH ADAIR Ore Dressing Consultant Bull Mtn. Rd., Asheville, N. C. Phone 4-1893 JAMES A. BARR Consulting Engineer Mt. Pleasant, Tennessee Washington, D.C. BEHRE DOLBEAR & COMPANY Consulting Mining Engineers and Geologists 11 Broadway New York 4, N. Y. I. R. BERENT Engineering Consultants and Contractors Mineral Exploration, Mine Evaluation, Mine Designs and Mine Management ` 188, Ataturk Bulvari-Ankara, Turkey BLANDFORD C. BURGESS Registered Professional Engineer Mining Consultant Monticello, Georgia GLENVILLE A. COLLINS Mining Engineer Uranium examinations Cable "Coins" 8 Haward-Canfleld Bldg. Santa Barbara, Calif.]

Jan 1, 1952