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By Charles A. Stetefeldt

This treatise is the sequel of a paper on "Russell's Improved Process for the Lixiviation of Silver-ores," etc., read at the Chicago meeting, in May, 1884, and published in the Transactions, vol. xiii., page 47. The facts it presents are principally compiled from Mr. Russell's notes on his practical experience gained in various places where the Russell process has been introduced. For a complete understanding of this paper a perusal of my former one is desirable, as can be seen from the frequent references here made to it. All silver-ores that do not carry a large percentage of lead or copper can be treated by Russell's process with success and economy. I do not mean to create the impression that from ores containing considerable quantities of lead and copper a high percentage of the silver cannot be extracted by this process. Such ores, however, will, in many localities, be reduced to better advantage by smelting. In case lead-bearing silver-ores are suitable for concentration, it may be profitable to concentrate the ore by Krom's dry system, obtaining a smelting-product high in lead, and to lixiviate the tailings and the dust. This plan has been adopted in a mill recently erected in Cortez District, Nevada. The dry system of concentration deserves the preference because it delivers the tailings and the dust in a condition ready for chloridizing-roasting. In wet concentration the drying of the tail ings would be expensive, and there would be a considerable loss of silver in slimes. Oxidized ores, containing silver chloride and lead minerals, may be lixiviated after crushing, and the tailings may be concentrated for lead. In this case wet concentration would be most suitable. This has been done at the Old Telegraph Mine, Utah. I would give, however, the preference to dry concentration in all cases which, of course, requires that concentration should precede lixiviation. The Russell process is also adapted to the treatment of tailings resulting from ores which have been worked either by the old

Jan 1, 1887

By William L. Fink, Dana W. Smith

In parts I1 and II2 of this series, there were presented results of investigations on the age-hardening of an aluminum-copper and an aluminum-magnesium alloy. It was shown that the simple precipitation theory of hardening3 adequately explained the aging phenomena, including certain so-called "anomalous" behaviors which had caused other investigators to reject or modify the precipitation theory. However, these papers did not discuss the double aging peaks, which have been stressed in recent articles by Dr. M. Cohen4 and Dr. M. L. V. Gayler.6 The present paper is devoted to an explanation of this "anomaly." Fig. 1 is a generalized schematic representation of aging curves at different temperatures. Curve A corresponds to the aging at the lowest temperature, and D at the highest temperature. Certain previous investigators have explained curve A and the initial peaks

Jan 1, 1938

By William L. Fink, Dana W. Smith

In parts I1 and II2 of this series, there were presented results of investigations on the age-hardening of an aluminum-copper and an aluminum-magnesium alloy. It was shown that the simple precipitation theory of hardening3 adequately explained the aging phenomena, including certain so-called "anomalous" behaviors which had caused other investigators to reject or modify the precipitation theory. However, these papers did not discuss the double aging peaks, which have been stressed in recent articles by Dr. M. Cohen4 and Dr. M. L. V. Gayler.6 The present paper is devoted to an explanation of this "anomaly." Fig. 1 is a generalized schematic representation of aging curves at different temperatures. Curve A corresponds to the aging at the lowest temperature, and D at the highest temperature. Certain previous investigators have explained curve A and the initial peaks

Jan 1, 1938

By FOSTER HEWElT

THE scope of this paper is the description of two districts in Peru in which deposits of vanadium have been found, and the consideration of much laboratory-work that I and others have done to determine the nature of these deposits. It is with regret that I present some of the data in a state of evident incompletion, particularly the analyses of a few of the minerals, which leaves some doubt as to whether the true nature of the minerals is understood. I make no apology, however, since in this case, as in many others referring to ore-deposits, conclusive opinions cannot be stated until a great amount of work has been done, and the deposit has been thoroughly exploited. I believe that the data and the tentative conclusions here presented indicate a unique and interesting condition which may assist others in work along similar lines; and further, what is of more practical importance, stimulate a search for a metal which, though long considered rare, is probably so merely because proper care has not been taken to recognize it. An excellent bibliography on the occurrence of vanadium in nature is given by F. W. Clarke in his paper, Data of Geo-chemistry;1 and in the preparation of this paper I have consulted many of the references contained in the Bibliography of the Chemistry of Vanadium, by M. Moissan.2 A brief review of the subject having special reference to the metallurgy of vanadium is contained in the small book by P.. Nicolardot.3 One of these vanadium-deposits has already been briefly

Mar 1, 1909

By Robert H. Leach, C. H. Chatfield

THIS paper gives a brief summary of the process of manufacture of sterling silver, and some of its more important physical properties, as observed in commercial production of rolled sheet and wire. Although papers have been published by Turner and Smith,1 Rose,2 Sperry3 and Jordan,4 there are few technical data available, and unfortunately the time allowed for the preparation of this paper has not been sufficient to make it as comprehensive as the title might indicate. ANALYSIS OF STERLING SILVER Fine or pure silver is too soft for coinage and the manufacture of articles in which strength and resistance to wear are desired. From the earliest times of which we have record, copper has been the metal generally used to harden silver. Analyses of coins and silver articles from ancient tombs show varying amounts of copper, and old Roman silver objects in the British Museum have approximately the same analysis as our sterling. The first authentic record of the establishment of a stand¬ard alloy is during the reign of Henry II in England. During the twelfth and thirteenth centuries, the people in the Eastern Provinces of Germany had a reputation for the standard and purity of their silver coinage, and it is said that Henry II employed some of these Easterlings, as they were called, to improve and standardize the English coinage, which had become debased. The peculiar standard adopted is probably accounted for by the system of weights used. A troy pound contains

Jan 1, 1928

Jan 1, 1879

By P. S. Katval

It is interesting to note that an attempt has been made to rationalize the effect of prestrain on the strength of Hastelloy X-280 after various aging treatments. However, two points raised by the authors seem to be somewhat unclear. 1) Concerning their Fig. l(a), the authors state: "Extensive dislocation networks are still in evidence. The 24-hr aging at 1500°F and the 15-min soak at 1350°F did not eliminate the dislocations introduced by the 20 pct cold reduction." This is, of course, to be expected since complete "elimination" of dislocations would require recrystallization which does not occur at 1500°F in Hastelloy X. However, recovery

Jan 1, 1969

By W. F. Guenther

The usual hand-operated drilling outfit consists of a 4-in. post-hole auger with 3/4,-in. pipe for drill stem, in 4-ft lengths, with a turning handle fitted to a top pipe T. The auxiliary tools are: a chisel-bit drill made from 3/4 or 7/8-in. tool steel welded to a 4-ft length of 3/4-in, pipe, so that the regular pipe string can be used; also a churn or "mule foot" made from 3-in. pipe, slotted on one side, belled to a 4-in. tempered cutting edge on the bottom, all welded to a 3/4-in. coupling by a yoke. Other tools required are pipe wrenches and cleanout tools made from old auto springs (Fig I). A 4 1/2 or 5-in. collar welded to a plate is often used to protect the mouth of the drill hole. In general the auger is used in the typical clay overburden and brown phosphate matrix, which is relatively soft. The churn or "mule foot1' is used in hard pan, lump phosphate or cherty ground. The drill is used for breaking flint, often found loose in the overburden. The drill with the chisel bit is used for trimming sides of the hole, sounding for lime bottom and breaking through hard lumps. Holes have been drilled to a depth of 80 ft, but the limit of efficient operation is about 50 ft. In deep holes it is necessary to unscrew the string in 20-ft lengths, to

Jan 1, 1948

By W. F. Guenther

The usual hand-operated drilling outfit consists of a 4-in. post-hole auger with 3/4,-in. pipe for drill stem, in 4-ft lengths, with a turning handle fitted to a top pipe T. The auxiliary tools are: a chisel-bit drill made from 3/4 or 7/8-in. tool steel welded to a 4-ft length of 3/4-in, pipe, so that the regular pipe string can be used; also a churn or "mule foot" made from 3-in. pipe, slotted on one side, belled to a 4-in. tempered cutting edge on the bottom, all welded to a 3/4-in. coupling by a yoke. Other tools required are pipe wrenches and cleanout tools made from old auto springs (Fig I). A 4 1/2 or 5-in. collar welded to a plate is often used to protect the mouth of the drill hole. In general the auger is used in the typical clay overburden and brown phosphate matrix, which is relatively soft. The churn or "mule foot1' is used in hard pan, lump phosphate or cherty ground. The drill is used for breaking flint, often found loose in the overburden. The drill with the chisel bit is used for trimming sides of the hole, sounding for lime bottom and breaking through hard lumps. Holes have been drilled to a depth of 80 ft, but the limit of efficient operation is about 50 ft. In deep holes it is necessary to unscrew the string in 20-ft lengths, to

Jan 1, 1948

By Perry Olcott .

THE Taka oil field is in the northern part of Titus and Franklin Counties, in north- eastern Texas. The small town of Talco, from which the field derives its name, is on the P. & Mt. P. R. R., about 15 mi. north of Mt. Pleasant, the county seat of Titus County. The oil field extends east and west from the town of Talco, the approximate center. In May, 1924, R. L. Cannon, while doing surface geology for the Humble. Oil & Refining Co., mapped the surface trace of this fault structure as evidenced by Upper Midway faulted down against Lower Midway. In the interval of sixteen years between the original surface work and the recent productive well completion, approximately eight wells were drilled into the Woodbine sand without success. The structure was well defined by those tests and all of the wells en-

Jan 1, 1936

By T. L. Joseph

BLAST furnaces are most efficient thermally when the C02 in the top gas is highest. Oxygen introduced in the air blast is converted to CO in the combustion zones. The extent to which CO, generated in front of the tuyères, is converted later to C02 depends upon the ratio of ore to coke in the charge and the degree to which C02, formed by reduction of iron oxides with CO, reverts to CO by the secondary reaction C + C02 = 2C0. About 300 to 400 lb. of carbon1 per ton of pig iron is normally involved in the solution-loss reaction or direct reduction of FeO with carbon, which produces the same over-all results; that is, lower C02 in the top gas. Riche has recently reported a reduction in fuel consumption at slower rates of blowing on two furnaces in spite of higher heat losses per ton of iron. Lower fuel consumption at slow operating rates was due to more complete reduction of the ore that resulted in higher C02 in the top gas and consequently more efficient use of carbon. Kinney3 has reported substantial savings in fuel as a result of crushing and sizing the ore charge. Improvements in practice brought about by sintering magnetite concentrates, flue dust and fine ores have been due to the establishment of conditions favoring more complete reduction of the ore in the upper part of the furnace. The extent to which oxides and fluctuations in composition in pig iron affect the quality of steel and finished product needs further study. There is evidence that more thorough preheating and reduction of the ore in the upper part of the furnace tend to give a better quality of iron. Bogatzkii4 found from laboratory work that the amount of oxygen enter-

Jan 1, 1936

By AIME AIME

THOUGH the dust-control systems in the crushing plants and other buildings at Morenci do not differ materially from similar installations in other large copper reduction works, it is probable that in few other plants has as much attention been paid to the dust problem. Possibly the most striking feature of the Morenci installation is the manner in which the necessary equipment has been built into the various structures, and the absence of unsightly pipes, ducts, and fan houses. That this result has been attained is due, in no small part, to the basic conception that the control of the dust in a milling plant should be an essential part of the process itself and not something to be tacked on later after the plant is in operation. The control systems were designed and developed along with the general plant construction program and when the first car of ore was dumped into the crusher the dust-control equipment was ready.

Jan 1, 1942

By J. M. GLEDHILL

(Washington Meeting, May, 1905.) A Discussion of Mr. J. M. Gledhill's paper, read by title at the Lake Superior meeting, but presented first at the New Yolk meeting of the Iron and Steel Institute (October, 1904), and here published under a mutual agreement. Between the two Institutes. Discussion. MR. E: WINDSOR RICHARDS, Past-President, said that at a recent meeting of the Institution of Mechanical Engineers a paper was read on tool steel, and he called the attention of the members to the high-speed tool steel at the Bethlehem Works. They would have the pleasure of seeing those wonderful works and would see 60, 70, 80 and 100 tons oil lathe with half-a-dozen of these high-speed tools running. PROP. H. M. HOWE (Columbia University) said that they all looked upon these high-speed tool steels as of very great importance, particularly to the machine shop. One point occurred to hire : Had it really been shown that Swedish steel is necessary, or better than equally pure steel that is not Swedish; and is cemented steel really necessary, and is there any advantage in using that, rather than equally pure open-hearth steel'! It might be well if the author could indicate the kind of evidence on which lie bases his assertion that it is necessary to have cemented Swedish steel. Many were hoping for the development of high-speed steels from elements which exist in great quantities, such as silicon, manganese and chromium, rather than from rarer metals like molybdenum, vanadium and tungsten, the supply of which is likely to be soon exhausted. If the high-cutting speed was to last more than a generation, it. seemed to him that they would have to draw upon the common ele¬ments and not upon the rare ones. MR. Tom WESTGARTH (Middlesbrough) said he fully appreci¬ated what had been said about the advantages of using high-speed steel, because great benefit had been derived from the

Mar 1, 1905

By R. W. Gurry

In the course of a series of measurements of the rate of diffusion of carbon in austenite at about 960°C. (1760°F.) and III0°C. (2030°F.), it became necessary to determine carbon concentration when austenite is saturated with graphite, because of indications that the hitherto accepted value of the solubility of graphite in this temperature range is too low. Specimens of carbonyl iron were saturated at temperature in a hydrogen-toluene atmosphere which was in equilibrium with graphite. The carbon conteDt of the steel was measured either by combustion or by the loss of weight after substantially complete decarburization in an atmosphere of hydrogen saturated at room temperature with water vapor. The absence of carbide or graphite as a phase at temperature was demonstrated by microscopic examination of saturated specimens that had been drastically quenched, The mean result of concordant ments-—taeats-is-^that gamma iron saturated with respect to graphite contains 1.39 per cent carbon at 957°C .(i755°F.) and 1.89 per cent at III0°C. (2030°F.). These two values, plotted along with what appears from the literature to be the best value (0.69 per cent) at the iron-graphite eutec-toid temperature (738°C. or I360°F.), yield a curve that is almost linear, and which, continued upward through a short interval, leads to a limiting solubility of 1.98 per cent at the iron-graphite eutectic temperature II35°C. (2075°F.) instead of the commonly accepted value of about 1.7 per cent. Experimental Procedure The samples of carbonyl iron, with the exception of those for microscopic examination, were cylinders 3.8 cm. long, 0.475 cm. in diameter. They were placed in a graphite holder and suspended in a vertical furnace, the temperature of which was controlled precisely by means of the resistance of the platinum winding.' In the empty furnace the range of temperature over a distance of 4 cm. at the heat center was 9°C. (I6°F.) but at a given location the temperature remained within +o.5°C. (o.9°F.); it was measured by inserting a platinum-rhodium couple calibrated at the melting point of palladium, 1555°C. Since the presence of the sample probably improved the uniformity of temperature, it was decided to consider the average temperature of the sample to be 3°C. lower than the maximum measured in the empty furnace with the same setting of the controller. Data were obtained in the vicinity of two temperatures, 960°C. (I760°F.) and III0°C. (2030°F.). The samples for microscopic examination, 2.2 cm. long, 0.475 cm. in diameter, were suspended individually on pure iron wire; for these no temperature correction was applied. The carburizing gas passed into the furnace was dry, oxygen-free hydrogen saturated at room temperature with toluene; this quickly produced on the

Jan 1, 1942

By R. W. Gurry

In the course of a series of measurements of the rate of diffusion of carbon in austenite at about 960°C. (1760°F.) and III0°C. (2030°F.), it became necessary to determine carbon concentration when austenite is saturated with graphite, because of indications that the hitherto accepted value of the solubility of graphite in this temperature range is too low. Specimens of carbonyl iron were saturated at temperature in a hydrogen-toluene atmosphere which was in equilibrium with graphite. The carbon conteDt of the steel was measured either by combustion or by the loss of weight after substantially complete decarburization in an atmosphere of hydrogen saturated at room temperature with water vapor. The absence of carbide or graphite as a phase at temperature was demonstrated by microscopic examination of saturated specimens that had been drastically quenched, The mean result of concordant ments-—taeats-is-^that gamma iron saturated with respect to graphite contains 1.39 per cent carbon at 957°C .(i755°F.) and 1.89 per cent at III0°C. (2030°F.). These two values, plotted along with what appears from the literature to be the best value (0.69 per cent) at the iron-graphite eutec-toid temperature (738°C. or I360°F.), yield a curve that is almost linear, and which, continued upward through a short interval, leads to a limiting solubility of 1.98 per cent at the iron-graphite eutectic temperature II35°C. (2075°F.) instead of the commonly accepted value of about 1.7 per cent. Experimental Procedure The samples of carbonyl iron, with the exception of those for microscopic examination, were cylinders 3.8 cm. long, 0.475 cm. in diameter. They were placed in a graphite holder and suspended in a vertical furnace, the temperature of which was controlled precisely by means of the resistance of the platinum winding.' In the empty furnace the range of temperature over a distance of 4 cm. at the heat center was 9°C. (I6°F.) but at a given location the temperature remained within +o.5°C. (o.9°F.); it was measured by inserting a platinum-rhodium couple calibrated at the melting point of palladium, 1555°C. Since the presence of the sample probably improved the uniformity of temperature, it was decided to consider the average temperature of the sample to be 3°C. lower than the maximum measured in the empty furnace with the same setting of the controller. Data were obtained in the vicinity of two temperatures, 960°C. (I760°F.) and III0°C. (2030°F.). The samples for microscopic examination, 2.2 cm. long, 0.475 cm. in diameter, were suspended individually on pure iron wire; for these no temperature correction was applied. The carburizing gas passed into the furnace was dry, oxygen-free hydrogen saturated at room temperature with toluene; this quickly produced on the

Jan 1, 1942

By Bedrand L. Johnson

THE phosphate-rock industry is built upon natural deposits of rocks and minerals in which the element phosphorus is present as a phoshate. The term ?phosphate rock? is a general one, applied to certain rocks of different degrees of consolidation and of diverese origin, charater and occurrence, composed of intimate mixtures of several phosphate minerals, largely submicrocrystalline, usually calcium phosphates, in commerical quantities, with various impurities. This term includes phosphatized limestones, sandstone, shales, and igneous rocks; nodular phosphates ; residual weathered phosphatic limestones ; vein phosphates ; and phosphatic sediments, both consolidated and unconsolidated.

Jan 1, 1944

The Industrial Minerals Division met jointly with the Materials and Equipment Division of the American Ceramic Society at State College, Pa, Sept 24-26 Headquarters were at the Nittany Lion Inn Thurs- day afternoon was devoted to a tour of inspection of the Bell Mine, American Lime and Stone Co , Bellefonte, Pa The party returned to State College for dinner and in the evening the Division's executive committee held a brief session There were four technical sessions Friday morning, Mining, afternoon, Beneficiation, Saturday morning, Industrial Minerals and Beneficiation There was an informal banquet at the Nittany Lion Inn Friday night with 93 present Edward Steidle was toastmaster Brief talks were made by President F C Flint and Secretary Ross Purdy, of the American Ceramic Society, Oliver Bowles, Chairman, Industrial Minerals Division, Adrian Morse, assistant to the president, Pennsylvania State College, and George Otis Smith, past president A I R'I E

Jan 1, 1937

[Separates of all the Pamphlets published within the last three years (starting with No. 1469) are available, with few exceptions, at Institute headquarters. Separates of all the Technical Publications are also available. All the papers are on file in public, university and technical libraries, and when so indicated in the list, may be found either in the TRANSACTIONS or in the special volumes issued by the Institute.] METAL MINING TRANS. PAMPHLET VOLUME NUMBER TITLE AUTHOR MEETING AND PAGE* -1033 Relation of Air Pressure to Drilling H. W. Seamon New York 66,743, 766 Speeds of Hammer Drills Feb., 1921 1034 Time Factor in Depletion of Mines J. W. Roberts New York - 66,711 Feb., 1921 1 1035 Calculation of Ore Tonnage and Grade J. E. Harding New York 66, 117, 122 from Drill-hole Samples- Feb., 1921 1038 Discussion of Papers Presented in 1920 1041 Run-off and Mine Drainage - H. N. Eavenson New York 66, 624, 630 Feb., 1921 1043 The Health of the Underground Worker A. J. Lanza New York Feb., 1921 1045 Dust-ventilation Studies in Metal D. Harrington New York 66, 272, 282 Mines Feb., 1921 1046 Discussion of Papers Presented at New York Meeting, 1921 1072 Breakage and Heat Treatment of Rock- B. F. Tillson New York 66,758 drill Steel Feb., 1921 1073 Discussion of Papers Presented at New York Meeting, 1921 1076-M Analysis of Some Drill-steel Tests F. B. Foley New York - 66,789 Feb., 1921 1077-M Application of Magnetic Analysis to C_ W. Burrows New York 66,796 Root Drills Feb., 1921 1078-M Heat Treatment of Rock-drill Steel G. H. Gilman New York 66,779 Feb., 1921 1080 What is the Ideal Drill Steel? F. H. Kingdon New York 66,807 Feb., 1921 1081 Rock Drill Steels, etc. W. T. Ober New York 66,814 Feb., 1921 1082-C Underground Mine Development, Its J. B. Dilworth Wilkes-Barre 66, 715, 721 Definition and Valuation Sept., 1921 1084 Drill Steel from Hollow Ingots P. A. E. Armstrong New York 66,809 Feb., 1921 1088 Authors' Replies to Recent Discussion 1092 Heat Treatment of Rock Drill Steel A. E. Perkins New York 66,811 Feb., 1921 1096-M Octagonal Ventilation Shaft of Davis- J. L. Bruce Wilkes-Barre 66, 252, 268 Daly Copper Co. Sept., 1921 1100-C Determination of Electrical Equip- G. Bright Wilkes-Barre 66, 580, 605 ment for a Mine Hoist Sept., 1921

Jan 1, 1926

By J. P. Carson

THE Croton water-shed furnishes the source and storage of watersupply to both the old and the new aqueduct. The Croton river rises in the southern part of Dutchess county, about 68 miles from the lower end of New York city. Its three main branches, called the East, Middle and West branches, flow southward across Putnam county, joining, near its southern boundary, to form the Croton, which continues thence in a general southwest direction across Westchester county to the Hudson river at Croton Point, about 35 miles north of the city. The water-shed above the proposed site of the Quaker Bridge dam extends about 33 miles north and south, with an average width of 11 miles, making in all about 362 square miles, from which, by complete storage, an average daily supply of 250,000,000 gallons may be collected—sufficient for the needs of the city, probably, for the next fifteen years. The water-shed above the Croton dam is 23 square miles smaller, and furnishes the present daily supply of 100,000,000 gallons. By referring to the map it will be seen that the shortest approximately straight line between the proposed site of Quaker Bridge

Jan 1, 1891

By Ta M. Li

Recent economic and environmental setbacks have not slowed Occidental Oil Shale, Inc.'s program aimed at the commercialization of oil shale. In fact, the firm expects to have a 795 MI (500C) bbl) per day production unit working by the end of 1976. The key to Occidental's ambitious program is an in situ method that extracts the valuable oil by retorting the shale in place. The process will require practically no water and will leave the spent shale in place underground. Additionally, all plant operations are to be located within the mine. These factors thus serve to make the operation attractive from an environmental viewpoint, in contrast to proposed conventional schemes which call for extensive underground mining, crushing and grinding at the surface, and construction of a massive surface retorting facility.

Jan 12, 1976