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By R. G. Ward, D. R. Gaskell

Using the maximum bubble pressure technique, the densities of iron silicates at 1410°C have been measured blowing helium, nitrogen, and argon. By ensuring equilibrium between the melt and the blowing gas with respect to oxygen potential and by minimizing tempcrature cycling of the furnace, iron precipitation in the melt has been prevented. Thus the previously reported effect of blowing-gas composition on the densities of the melts has been eliminated. Consideration of the oxygen densities of the melts gives an indication of the structural changes accompanying composition change. The density-composition relationship of iron oxide-silica melts in contact with solid iron has been the subject of several investigations1-7 and considerable disparities exist among the various results obtained. Of these investigations, all except one5 have employed the maximum bubble pressure method. In the most recently reported of these investigations1 the density-composition relationship obtained blowing nitrogen differed from that obtained blowing argon. The measured densities obtained under nitrogen were greater than those obtained under argon, the difference being a maximum at the pure liquid iron oxide composition and decreasing with increasing silica content. This observation rationalized the disparities existing among the results of the earlier investigations, showing that two lines, one for nitrogen and the other for argon, could be drawn to fit all the earlier results. No explanation for this phenomenon could be offered. Chemical analysis of rapidly quenched samples of melt for dissolved nitrogen, and direct weighing measurements, excluded solution of nitrogen in the melt from being the cause of the increase in density. The range of blowing gases was extended by Ward and Hendersons who measured the density of liquid iron oxide bubbling helium, nitrogen, neon, argon, and krypton. The measured density was found to decrease smoothly with increasing atomic number of the bubbling gas. The work reported here is a continuation of the program initiated by Ward and Sachdev7 to study the densities in multicomponent melts in which the iron oxide-silica system is the solvent. As such it is necessary to explain or eliminate the anomalous densities of iron silicates under different atmospheres, and the present rede termination was carried out towards this end. EXPERIMENTAL The maximum bubble pressure method of density determination was again employed and the experimen- tal apparatus used was essentially the same as that used by Ward and Sachdev.7 A molybdenum-wound resistance furnace heated an ingot iron crucible of internal diameter 1 in. containing a 2-in. depth of melt. The bubbling gas was blown through a 1/4 -in.-diam mild steel tube onto the end of which was welded a 2-in. extension of 1/4 -in.-diam ingot iron rod, drilled out to 5/32 in., and chamfered to an angle of 45 deg. The blowing tube was introduced to the furnace through a sliding seal and its position was controlled by a vertically mounted micrometer screw which allowed the depth of immersion to be determined with an accuracy of ± 0.01 cm. A Pt/Pt-10 pct Rh thermocouple was located below the crucible and temperature control was effected initially by means of an on-off controller and later by a saturable core reactor. The bubble pressure was determined by measurement of a dibutyl phthalate manometer using a cathetometer. PREPARATION OF MATERIALS Iron oxide was produced by melting ferric oxide in an inductively heated iron crucible in air. The liquid was quenched by pouring onto an iron plate. Silica was prepared by dehydrating silicic acid at 650°C for 12 hr. RESULTS Before any measurements of the density of a melt were made, the density of distilled water at room temperature was measured bubbling helium and argon. Both gases gave the density as 1.00 ± 0.01 g per cu cm which showed that the density of the manometric fluid (dibutyl phthalate) was not affected by contact with the blowing gas. With the furnace controlled by an on-off temperature controller an attempt was made to measure the density of pure liquid iron oxide by bubbling argon. The furnace atmosphere gas and bubbling gas were dried over magnesium perchlorate and deoxidized over copper turnings at 600°C. It was found that the pressure required to blow a bubble at a given depth increased slowly with time, and thus it was impossible to obtain a unique value for the density of the melt. Inspection of the blowing tube after removal from the furnace showed that rings of dendritic iron had precipitated from the melt onto the immersed part of the tube. This is shown in Fig. l(a) where the various "steps" correspond to different depths of immersion. The precipitation of iron was considered to be due to one or both of two possible causes: i) The composition of the liquid iron oxide is that of the liquidus at the temperature under consideration and can be expressed by the equilibrium

Jan 1, 1968

By Paul E. Rosten

Introduction This papers describes some of the latest improvements that have been incorporated or planned by the Cleveland-Cliffs Iron Co. to reduce operating costs and improve pellet quality. The Cleveland-Cliffs Iron Co. operates and manages mining, beneficiation, and pelletizing operations in Michigan, Canada, and western Australia. This paper deals with the grate-kiln pelletizing operations at Republic, Humboldt, Tilden, Empire, and Pioneer in Michigan, and the Adams and Sherman in Ontario, Canada. Table I characterizes each operation in regard to location, ore type, pellet capacity and date that pellets were first produced. All of the operations with the exception of Pioneer and Tilden, utilize downdraft-two-pass grate cycles of drying followed by preheating. Pioneer utilizes an all-downdraft, three-pass grate cycle which consists of three drying zones followed by the preheat zone. The Pioneer and Tilden cycles have been described previously (Lindroos and Koski, 1966; Villar and Dawe, 1975; Koski, 1977). Tilden utilizes a three-pass grate cycle with a stage of updraft drying, followed by two downdraft drying stages. Recuperation systems which supply hot gases to a drying zone from second stage cooling were designed and fur¬nished for Tilden I. Tilden II will be identical. Empire IV will also be furnished with a recuperation system. The Adams grate¬kiln system was retrofitted with a recuperation system. This paper will summarize some of the efforts that are in effect or planned for grate-kiln pelletizing systems to: (1) reduce operating and maintenance costs, (2) reduce energy requirements, (3) improve product quality, and (4) meet environmental standards.

Jan 1, 1981

By Blamey Stevens

(San Francisco Meeting, October, 1911.) IN this paper, which is a logical extension of my paper, The Laws of Intrusion, 1 the various pressures of emanation and their mechanical causes and effects on the large scale of nature are determined, .and a classification of emanations is deduced therefrom. The Subterranean Sea. The subterranean sea is here defined as the intercommunicating water contained in the trains of pores and fissures of the rocks down to great depths. Whether the actual amount of water constituting this subterranean sea be large or small, does not enter into the present argument, since the static pressure of this water at any particular depth is not a function of the quantity : it involves only the depth and the density of the water. Densities. The total pressure at depths down to 10 or 15 miles is made up of the rock-stresses investigated in my previous papers, and the pressure of the subterranean sea. The latter component must evidently be equal to the weight of a solid column of the overlying water of unit sectional area. As water expands with heat, it should really be necessary to sum the density at every level. A knowledge of the densities of water under a variety of conditions is therefore needed, but does not seem ever to have been ascertained for such combined pressures and temperatures as we have to consider. The specific gravity of water at 28° C. for various pressures up to 400 atmospheres, has been determined by Barus,2 who

Apr 1, 1912

By TRUMAN S. FULLER

THE GREAT INTEREST in decomposition and trans- formation, so evident in the study of alloys during the last two years, was reflected in the many papers on this subject, presented at the first session of the Institute of Metals, Tuesday morning. Dr. F. A. Thomson, of Montana State School of Mines, presented the first paper by C. Wilson, H. F. Silliman, and E. C. Little, "Rate of Precipitation of Nickel Silicide and Cobalt Silicide in the Hardenable Copper-nickel-silicon and Copper- cobalt-silicon Alloys." Dr. R. F. Mehl, in discussing this paper, stated that the title was somewhat deceptive, as it indicated that the rate of precipitation is determined; the method used is a measurement of electrical conductivity and hardness, neither of which is suitable for a quantitative measurement of rates of reaction or precipitation in the solid state. Hardness is also uncertain because it depends so much upon particle size. Of the various methods proposed for the study of rate of reaction and precipitation the evaluation of volume of reaction produced from the area of photomicrograph is the best.

Jan 1, 1933

By L. A. Geoffrion, R. H. Perkins, J. C. Biery

Densities of cerium metal and several lour-melting binary cerium alloys were measured over the range 25° to 800°C. A rolumeter, using NaK as working fluid, was used to obtain the data. The cerium, Ce-Co, Ce-Ni, and Ce-Cu alloys all exhibited an increase in density on melting, while a Ce-Mn alloy expanded on melting. FOR the proper design of a nuclear reactor, the change in density of the fuel with temperature must be known. This is especially important in a system utilizing molten fuel, such as LAMPRE (Los Alamos Molten Plutonium Reactor Experiment), since a relatively large change in density usually occurs during the solid-liquid transition. The fuel for LAMPRE is a Pu-2.5 wt pct Fe alloy with a melting temperature of 410°C. However, limitations in reactor design with this fuel have led to consideration of other plutonium-containing alloys for use in future generations of this type of reactor. Several ternary alloys containing plutonium and cerium as two components have satisfactorily low melting points. The system that at the present time appears to be most acceptable is Pu-Ce-Co; it exhibits little change in melting temperature with wide variation in plutonium concentration. Other alloys that have received some consideration contain nickel, copper, and manganese as the third constituent. The proposed fuel alloys are difficult to handle experimentally in the 25" to 800°C temperature range since they oxidize readily, react with many solvents, and contain a poisonous fissionable material. In addition, in this temperature range the alloys pass through the solid-liquid transition. Several techniques are available for measuring the densities and volume coefficients of expansion of solids or liquids. However, the only apparatus that appears suitable for measuring expansion coefficients over this temperature range and through the phase transition is a volumeter. In a volumeter, the indicating medium must be essentially inert to and insoluble in the material being studied. It must also possess a low vapor pressure over the operating temperature range, and its coefficient of expansion must be accurately known. One material that is satisfactory in nearly all of these respects is the alloy Na-78 wt pct K, which melts at -10°C and has a vapor pressure of 860 mm Hg at 800°C. This relatively high vapor pressure at 800°C requires an overpressure of an inert gas to prevent boiling. While a volumeter is capable of determining accurately the volume coefficients of expansion of materials, it cannot be used for absolute density measurements. Therefore, a density determination at a known temperature must be coupled with the volumeter measurements to give all the desired data. The weight-loss technique using immersion in bromobenzene at room temperature proved to be satisfactory. The preliminary work that was done on this experimental program involved developing and calibrating the equipment, and measuring the densities and volume coefficients of expansion of cerium and some low-melting binary cerium alloys. The complications that are caused with the introduction of plutonium into the system were avoided until the equipment was proved to be satisfactory and until experience was gained in its operation. It is this first phase of the experimental work that is described in this report. DESCRIPTION OF EQUIPMENT AND OPERATING PROCEDURE The NaK volumeter is shown schematically in Fig. 1. Basically, the equipment consists of two weld-sealed stainless-steel containers of nearly identical volume. One container holds a tantalum crucible and the specimen being measured; the other contains a tantalum crucible and a tantalum specimen used as a control reference material. To avoid temperature gradients, the bombs are located in a copper block inside the furnace. Stainless-steel capillaries of equal length and volume connect each stainless-steel container to a glass viewing capillary. The stainless-steel containers, stainless-steel capillaries, and a portion of the glass capillaries are filled with NaK (22 wt pct Na-78 wt pct K). The NaK/gas interface in the glass capillary is viewed with a cathetometer which is accurate to *0.5 mm. The cathetometer readings are used to calculate the volume changes of the samples during a run. This volumeter is basically the same as that described by F. Knight in Plutonium 1960. 2 However, changes in equipment design and operating procedure were made to eliminate some major operating difficulties. These changes are summarized below. 1) In filling the manometer with NaK, gas was frequently entrained in the system. Evacuation of the system before filling failed to eliminate the en-

Jan 1, 1965

By S. F. Emmons

The first paper which appears in the published Transactions of our Institute is that read by our respected Secretary at its first meeting in Wilkes-Barre in May, 1871. It is entitled " The Geographical Distribution of Mining Districts in the United States," and presents a brief but masterly review of what was known of the distribution of our deposits of useful minerals, particularly the metals, not only from a geographical but from a geological stand-point. At the request of Dr. Raymond I agreed, somewhat hastily, perhaps, to write for this occasion a brief sketch of the geological distribution of the deposits of the useful metals in this country, in the light of the increased knowledge of the present day. In the time given no personal investigation was possible, and as it was therefore out of the question to attempt to make anything that could be considered an original contribution to the history of our ore-deposits, I have been obliged to limit myself to an examination of such pub-

Jan 1, 1894

By Joseph T. Roy

MINING revival during the last few years has brought about a considerable increase in the number of gold and silver determinations made, noticeable in all branches of the industry but especially so in the business of a custom smelter. At East Helena, solely a custom smelter the assay department found that the four assay furnaces available were inadequate to handle the increased amount of work. These furnaces were of a standard design, having duplex muffles, one superimposed on the other; each muffle was 12 1/2 in. wide, 18 1/4 in. long and 6 in. high, and could handle 72 cupels or 20 fusions. Since the heat varied considerably between the upper and lower muffles, cupellations were not ruin in both at the same time. To speed up assaying, E. A. Meale, chief chemist, had the happy idea of enlarging a muffle furnace, originally designed by the Montana Power Co., so that one muffle would acconmmodate at least as many determinations as the duplex muffles. An order was given to the Denver Fire Clay Co. for a Carbofrax muffle of the size required and the local engineering department enlarged the furnace to accommodate the muffle. Details of the

Jan 1, 1938

By Alexander R. Troiano, Taylor Lyman

Studies of the transformation of aus-tenite at constant subcritical temperatures have been numerous since the work of Davenport and Rain.' Considerable information has been obtained on low-alloy steels and on high-carbon alloys containing undissolved carbide or graphite at the austenitizing temperature. Little is known of the isothermal transformation of aus-tenite containing in solution large amounts of both carbon and a single alloying element. In this investigation four steels containing one per cent carbon and with chromium in the range 3 to 9 per cent have been examined with the view to establishing the fundamental character of the isothermal reactions when all carbon and chromium are initially in solution in austenite. Experimental Procedure Alloys The chemical compositions of the steels investigated are given in Table I. The 4 per cent Cr alloy is a commercial steel. The other steels were made by the Carpenter Steel Co. as 50-lb., induction-furnace heats and rolled to 5/8 -in. round bars. Bars were softened at 650' to 700°C. before the specimens were cut. Most of the lines on the transformation diagrams presented here have been placed on the basis of the microscopic examinatioll of partially reacted specimens, Thees specimens were approximately 1/2 by 1/4 by 1/8 in. ill size, specimens of the 9 per cent cr steel were held 10 to 12 hr, at 1200°to 1225°C. before quenching to the various subcritical temperatures. The other steels were held for 2 to 2 1/2 hr. at 12ooOC. before quenching. These treatments, carried out in an atmosphere of purified nitrogen, produced an austenite grain size larger than A.S.T.M. So. I, some grains being 1 to 2 mm. in diameter. There were a few undissolved carbide particles in some specimens of the 9 per cent Cr steel. It is believed, however, that any errors in the results due to incomplete solution of carbon and chromium in austenite are negligible; that is, austenite compositions may be considered as being those listed ill Table I. X-ray Methods Constituents were identified and mar-tensite axial ratios determined from Debye

Jan 1, 1945

By W. A. Wall, R. L. Kidd

IN present-day flotation practice, grinding of the flotation feed is carried to extremely fine sizes, 70 to 80 per cent minus 200 mesh being customary. The greatest flotation losses occur in the coarsest and finest sizes, but the losses in the very fine sizes are, of course, much the more important because of the large proportion of fines in the feed. These losses are particularly high in zinc ores so a study of the effect of size on the flotation of sphalerite has been made. The mineral used in these experi¬ments was a pure sphalerite, especially free from copper, from the Joplin district in Missouri. The sizes coarser than 200 mesh were separated by screening, the sized mineral then being deslimed on a Wilfley table. The sizes finer than 200 mesh were obtained by water elutriation as described by H. R. Bradford (M. S. Thesis, University of Utah, 1932) ; particles finer than 6.5 microns could not be obtained with the apparatus used.

Jan 1, 1933

By G. D. TRANT

HOT metal is commonly transported from the blast furnace to the open hearth by one or the other of two general methods: (1) by hot-metal ladles, usually in conjunction with a stationary mixer, or; (2) by means of mixer-type ladle cars, taking the place of both the hot-metal ladles and the stationary mixer. In both cases, the use of transfer ladles for charging the metal into the open-hearth furnaces is necessary. The American Rolling Mill Co. at its Middletown division, adopted hot metal practice on. June 2, 1928. The pig iron is produced' in a .blast furnace about 11 miles from the open-hearth furnaces, and is trans- ported in Pugh-type mixer cars having a capacity of 150 gross tons each. Three cars are in service and handle the delivery of hot metal to the pig machine and the open-hearth furnaces. The capacity of the blast furnace is 550 tons and casts are made every four hours.

Jan 1, 1929

Jan 1, 1925

By Gerald J. Anderson

The Marquette District of Central Northern Michigan is the oldest of the Lake Superior iron districts with a mining history dating from 1852 up to the present. The total production of all types of ore through 1965 was 338,120, 146 long tons. Emphasis up to the 1950's was on mining the direct shipping ores; however, demands for higher-grade and better-structured ores in the last decade has resulted in a complete shift in emphasis to beneficiating the lowgrade Negaunee Iron-formation to produce high-grade iron ore pellets. The Precambrian sediments of the Marquette Range have been correlated with the Animikie Series of the Thunder Bay District, Ontario, and are contained in a westward plunging synclinorium that is approximately 3 3 miles in length and 3 to 6 miles in width. -The rock unit of major economic importance is the Negaunee Iron-formation that reaches a thickness of 2500 feet near the City of Negaunee. The primary iron content of the Negaunee Iron-formation averages 26 per cent, whereas the altered iron-formation approximates 31 per cent. The Negaunee Iron-formation has been divided into three principal types: diagenetic, oxidized, and metamorphic. The ores produced to date fall into four categories: high-grade soft ores, high-grade hard ores, siliceous ores, and concentrates and agglomerates (pellets). The soft ores generally are found in synclines and in fault-trough structures, bounded by mafic dikes along at least one side, and are mainly found in the basal portion of the Negaunee. In contrast, the hard ores occur in the uppermost portion of the Negaunee and are controlled by structural features such as folds, faults, and dikes. Iron-formation that has undergone diagenetic and metamorphic alteration makes up the main beneficiating ore types. Studies on the Negaunee Iron-formation have played an important role in the formulation of many of the theories on the origin of the Precambrian iron-formations.

Jan 1, 1968

By Fuller, T. S.

THE number of rare or uncommon elements in use in the electrical industry nowadays is large, their application having come about through investigational work in industrial search laboratories and ' educational institutions. Such elements, together with those whose properties are more generally known, constitute Nature's gift to mankind and make possible the intricate devices which further our modern civilization. The' quality of raiaity is one of degree, and obviously depends largely on one's point of view. From the standpoint of quantity measured in the customary units of weight and volume, the amounts of many of the elements required are extremely small, but from the of view of performing some particular function or .other in a manner more satisfactory or cheaply than can be accomplished by any other sub- stance, the use in question may be extremely important.

Jan 1, 1928

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

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

Jan 1, 1944

By M. N., Short

TIE Pioneer mining district, better known as the Superior district, from its principal town, is located in Pinal County in south-central Arizona about 80 miles east of Phoenix and 22 miles west of Miami. The region embraces a confused series of mountain ranges of moderate FIG. I.----SUPERIOR, LOOKING NORTH FROM SOUTH BANK OF QUEEN CREEK. MAGMA MINE IS INDICATED BY WASTE DUMP IN GULCH TO RIGHT OF CENTER. height but precipitous slopes, between which lie irregular valleys filled with alluvial detritus. The average elevation is about 2800 ft. in the valleys and the summits of the ranges reach 2000 ft. above this. Superior is situated on the north bank of Queen Creek where it emerges from one of those ranges into a more or less basin-shaped valley. The drainage of Queen Creek is to the southwest and the flood waters spread out and lose themselves in the desert northeast of Florence, the county seat of Pinal County.

Jan 2, 1926

DEFENSE Materials Procurement Agency has been moving rapidly to encourage copper industry expansion programs. Although copper production is at a high level, a shortage exists on a world-wide basis as well as on the domestic scene. Projected expansion programs will not ease this current demand for most of them are 2 to 5 years off. Refining facilities are adequate but there is a shortage of ore and scrap, and it is for this reason that the expansion programs are directed at developing more sources of supply. The domestic expansion programmed thus far and understood to have been arranged with price escalation should the domestic price go to 271/20, were summarized by American Metal Markets as follows (dates of announcement are given in parenthesis: .1-Copper Cities Mining Co.'s, $15,000,000 expansion near Miami, Ariz., to be operating about 1954. DMPA will buy 22,500 tons of copper a year up to a given amount on an agreed price of 23¢ per pound, with some exceptions and depending upon salability at a higher price to other purchasers in the U. S. (September 25th). 2-An RFC loan of $60,000 to North Butte Mining Co. to be paid off on the basis of deliveries at a purchase price of 241/20 per pound (September 25th). 3-A $25,000,000 expansion program by Phelps Dodge to provide 38,000 tons per year by late 1954. DMPA would purchase it at a price of 22¢ per pound up to 112,500 tons providing other purchasers in the U. S. will not pay a higher price (September 26th). 4-Anaconda Copper Mining Co. $40,000,000 expansion in Nevada to provide more than 30,000 (might be increased to 45,000) tons per year. DMPA would purchase the copper at 250 per pound for a limited period of time if it is not salable to industrial users at above this price. Production would start around 1953 (November 14th).

Jan 1, 1952

By J. D. Lubahn

The influence of precipitation from solid solution on the subsequent deformation resistance of alloys is well known. However, the influence of precipitation or aging that occurs simultaneously with deformation may be entirely different and of considerable importance. It is thought1 that the presence or absence of a yield point jog in impure iron at room temperature and the presence or absence of discontinuous flow at higher temperatures may be directly related to aging phenomena, particularly since the yield point jog is absent when the carbon and nitrogen are sufficiently removed.2 As a preliminary attack on the problem of simultaneous aging and deformation, three kinds of tests—constant strain rate tensile tests, constant load creep tests, and variable strain rate tensile tests—were carried out on an age hardenahle aluminum alloy. Constant Strain Rate Tensile Tests Stress-strain curves at a strain rale of about 0.001 min-1 were obtained for specimens of 61S that had been quenched into liquid nitrogen after a one-hour solution treatment at 521°C, then aged at room temperature 10 min., 20 min., 4 hr, and 26.5 hr before testing. Strain-time curves were obtained on the same chart with the stress-strain curve by means of an auxiliary pen, driven parallel to the axis of the chart drum at constant speed by a synchronous motor and gear chain. The angle of rotation of the chart drum was proportional to strain. The strain rates reported are the measured slopes of the strain time curves. Constant strain rate was approximated (within a factor of 2) by manual adjustment of the oil inlet valve of the hydraulic testing machine in such a way that the course of the recorder pen was parallel to pre-drawn strain-time lines of the desired slope. The specimens were machined from 9/16 in. rod. The cylindrical portion was 0.357 in. in diam by 13/4 in. long and

Jan 1, 1950

By M. W. Von Bernewitz

AN important regional meeting of the American Institute of Mining and Metallurgical Engineers was held, at Salt Lake City on Aug. 22 to 26, jointly with the fifth annual meeting of the Western Division of the American Mining Congress. The whole meeting was marked by enthusiasm, keen attention to the subjects under discussion, and many renewals of personal contacts. The trips to the various plants were well attended and the local press paid much attention to the meeting. The A. I. M. E. sessions began Aug. 23, with a non-technical morning session. J. 0. Elton, manager for the International Smelting Co., presided. The purpose of this session was to present in a non-technical manner the relation of flotation to mining, smelting, and the State. Ernest Gayford, metallurgist with the General En-gineering Co. of Salt Lake City, gave the definitions of flotation as suggested by Rickard, the dictionary, Weinig, and Taggart. The active agent in flotation is the air bubble, and the two prime requisites are the formation of bubbles and the creation of selective action of the bubbles for metallic particles instead of for gangue particles. Broadly, all the sulfides are floatable minerals, but the oxides, carbonates, silicates and sulfates are not. As far as Utah is concerned, flotation has been one of the greatest means of conserving its natural re-sources, because it has converted millions of tons of waste rock into pay ore; it is recovering millions of pounds of metal formerly lost in tailings; it has con-verted the zinc from a liability into an asset; and has kept thousands of men at work and distributed millions in dividends for the benefit of the State. As to the future of flotation, Mr. Gayford can con-ceive that the next 5 or 10 years may see as much, if not more, advance than was made in the preceding period. The big problem is dressing oxides, carbonates, silicates, and sulfates, and simplification of the number of reagents, also the separation of different gangue min-erals from one another.

Jan 10, 1927

By Erwin S. Sperry

Some time ago, the author had occasion to make an alloy of equal parts of nickel and aluminum, for the purpose of adding small amounts of nickel to pure aluminum. The nickel was melted in a plumbago crucible under a layer of borax ; and at a proper temperature the aluminum was added, and the whole mass was stirred with a plumbago stirrer. The alloy immediately became incandescent and boiled. It was then poured into iron moulds, in the form of ingots weighing about 10 pounds. The metal when poured was very fluid and free from the viscosity so often noticed in nickel and nickel-alloys. The color of the alloy is gray, not unlike that of wrought-iron, and the fracture is devoid of any crystalline appearance. It is quite brittle, and can be readily ground to a powder in a mortar. More metal was made than was needed; and what remained unused was placed in a covered wooden box and set away. In about three months, as it mas again necessary to use the alloy, the box was opened; and, much to my surprise, nothing but a dark gray powder was found in it. This condition of the alloy could not be accounted for. An attempt was made to melt the powder and pour it again into ingots, but with negative results. Analogy pointed to disintegration; and it was decided to make a fresh sample of the alloy, and watch the material from the beginning. In the second experiment the conditions were identical with those of the first, with the exception that fluor spar was substituted for the borax. This change was made because it was thought that perhaps the borax might have been

Jan 1, 1900

By Porter W. Shimer

(New York Meeting, February, 1912.) IT does not seem to be generally known that some American pig-irons contain notable amounts of vanadium, and while the present investigation is far from covering the whole range of irons, it is hoped that, at least, it may serve to call attention to the importance of looking for this element. The majority of the pig-irons investigated were made in the Lehigh Valley and neighboring furnaces, using more or less New Jersey magnetite in their mixtures. Many of these ores, and probably all of them, contain a little vanadium as well as titanium; the ore from one of the largest of these mines contains 0.05 per cent. of vanadium and 0.60 per cent. of titanium. Dr. Thomas M. Drown was the first to detect the presence. of vanadium in the incrustations 1 occurring on certain pig-irons, and he also found this element in a number of magnetites, but the methods for its accurate determination had not, at that time, been well worked out. In a general way, it may be said that the Lehigh Valley pig-irons contain from 0.02 to 0.05 per cent. of vanadium and from 0.10 to 0.20 per cent. of titanium. These elements follow the silicon; that is, the furnace-conditions which produce a high-silicon, low-sulphur iron will cause the maximum reduction of vanadium and titanium, and the lower grades of iron, with low silicon and high sulphur, have a lower content of these elements. The following analyses of irons made from the same mixture, but under varying furnace-conditions, show this very well Vanadium. Silicon. Sulphur. Per Cent. Per Cent. Per Cent. NO. 1 X, . . . 0.042 3.46 0.022 No. 2 plain, . . 0.038 2.26 0.041 Mottled, . . . 0.0'29 0.52 0.106 1 Robertson and Firmstone, Note Concerning Certain Incrustations on Pig Iron,Trans., xii., 641 (1883-84).

Aug 1, 1912