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By F. R. Jones

T Tahawus, N. Y., National Lead Co. operates the MacIntyre development. Here the world's largest titanium mine produces 5200 long tons of ore per day and pours 8000 long tons of waste rock over its dumps. Concentrated ilmenite is sent by rail to National Lead Co. pigment plants, and a second product, magnetite, is sold to steel producers in raw form or is agglomerated and shipped as sinter. Several earlier attempts had been made to produce iron from the deposits, which have been known since 1826. These attempts failed, chiefly because of titanium impurity. In 1941 the present owners re-established the operation for production of war-scarce ilmenite, and the impurity became the main product.

May 1, 1956

By R. D. Parks

DESPITE the handicap of reduced production in many districts, the mining industry in 1938 forged steadily ahead toward solution of its minor technical problems and has of-defected major advances in several fields. In California hydraulic mining for gold, shut down for forty years, will shortly be resumed following revision of restrictive laws. Disposal of hydraulicked ground is to be regulated by settling dams so as not to interfere with agriculture. Gold mining has been aided also by the development of a new high-efficiency dry amalgamator which applies the Ramsay mercury separator to the original de Phily process. Based on the principle that crushed ore will follow a rod into a mercury bath, this simple device is primarily adapted to dry areas and is to be available in small, multiple units suitable

Jan 1, 1939

By Max Kraut

UNTIL VERY RECENTLY the flotation process has not found much application in the treatment of gold ores. No appreciable improvement has been made lately in the technology of this application; but the possibilities of flotation have been more fully appreciated. Excellent results were obtained long ago, but few operators paid much attention to them. For instance, in 1915 extensive experiments were carried out by Mr. Beauchamp and Minerals Separation on ores from the Dutch-Sweeney mine near Jimtown, Calif. The ore contained gold-bearing pyrite and laboratory tests indicated a 10c. tailing on a $6 head. In 1918 a 300-ton flotation mill using Minerals Separation machines was built based on the results obtained. However, when the mill began full-scale operation, mill heads did not come up to expectation, being only $4; also the-tonnage was considerably less than had been expected. Flotation mill tailing assayed 15c., indicating a recovery of over 96 per cent, so that excellent metallurgical results were obtained. The operation was a success but the patient died.

Jan 1, 1932

By Adrian C. Dorenfeld

Concentradora "Doña Aida" (100 t /d capacity) was built in 1971-72 to treat dumps and ores containing mixed oxide-sulfide copper-gold-silver minerals derived from two veins. The veins, Don Felipe and Maria, are about 150 m apart, but are distinctly different mineralogically. The deposits are near Sun Juan de Guadalupe, Durango, Mexico. All new process equipment was manufactured locally, in or near Torreon, Coahuilu. Sampling, ore testing, flowsheet design, plant design, drawings, purchasing, financing, and construction, etc., were planned and directed by two engineers. Construction was executed by local miners and common labor (largely agricultural). The paper presents detailed costs for equipment and construction. The subsequent breaking-in operation is discussed.

Jan 1, 1982

Jan 1, 1909

[OH. O'C. Acker '86 Jinzoc Adachi '88 *Truman H. Aldrich '78 Walter H. Aldridge '89 *Anson W. Allen '87 *John H. Allen '84 *Thomas Andrews '94 *William R. Appleby'90 *W. Lawrence Austin '82 . S. Ayres'73]

Jan 1, 1946

By F. J. Tuck

THE Hayden mill of the Ray Mines Division, Kennecott Copper Corporation, is now equipped with two 9 by 12-ft. rod mills having a daily capacity of 6000 tons of coarse-crushing plant product from the mine. These two mills crush a ¾ -in. product to approximately 19 per cent on 14 mesh, with only one pass through the mills. Each rod mill has taken the place of four sets of 42-in. Garfield rolls with their attendant screens, and is making a product for the fine-grinding department comparable to that formerly made by rolls in closed circuit with screens. The rod mills are lined with wave-type liners of white iron, varying in thickness from 2 to 3 in. The shell and end liners last approximately 600 to 700 days. Manganese-steel lifter bars, 3 5/8 in. thick, are used, spaced about 11 in. apart, and they give a life of 350 to 450 days. Fig. 1 shows the general design and thickness of the wave-type liners and lifter bars; 1 ½ -in. liner bolts are used to fasten the lifter bars to the shell. The shell liners are held in place by the tapered lifter bars. A 3/4-in. wood backing is used between the shell and the liners. The rod-mill scoop has removable manganese-steel lips, which last 250 to 300 days. The scoop proper has shown some wear in spots, and these spots have been protected by rubber bolted over them. Water and milk of lime are added to the elevator feeding the mill, but not enough water to cause a pounding of the rods against the shell. Roughly, the water added amounts to 25 to 33 per cent of the ore. Additional water is added to the mill discharge to facilitate distribution to the classifier bowls in the fine-grinding department. Rods are charged to the mill once every four days, the mill being down about 20 min. for this purpose. Other delays are negligible, and usually are due to a loose liner bolt or possibly power trouble. However, these occasions are extremely rare. In charging the mill, a crane is used

Jan 1, 1938

By John V. Beall

Since the U. S. Metals Refining Co. works was established, around the turn of the century, near the town which is now called Carteret, N. J., it has grown to be a major producer of refined copper and the main source of that special brand known as "oxygen-free high-conductivity copper." Owing to the complex metallurgical problems arising from handling a variety of raw materials such as copper concentrate from Matahambre, Cuba, copper and brass scrap from the New York area, and domestic blister copper, the organization is geared from top management down through its 2000 employes to maintain a high degree of flexibility in plant operation. The Company is a subsidiary of The American Metal Co. Charges for the smelter furnaces, one reverberatory furnace and one blast furnace, are made up in. bedding bins so that they may be tailored to the production of a constant grade of blister copper. The reverberatory furnace smelts the .sulphide charge, which may be a blend of ten different materials but principally the Cuban concentrate, and the matte from the process is poured into a converter. This reverberatory is 80 by 20 ft, silica lined with a slag bottom, fired by pulverized coal, and continuously side-charged from the top by bottom-dump cars which keep the side walls covered. It produces a 40 to 50 per cent copper matte. The fuel-charge ratio is 4.35 tons of solid charge per ton of coal. The furnace has a capacity of 10,000 tons of charge per month and produces from 5000 to 6000 tons of slag per month which must be disposed of. About 5000 tons of converter slag is produced monthly and returned molten to the reverberatory furnace. The converter gases go through a spray chamber to a Cottrell precipitator and thence to the flue system. Smoke from the

Jan 1, 1948

By J. H. Wernick

IN a study of the rate of decomposition of ½ -in. cubes of limestone, dolomitic limestone, and dolomite in a sweeping nitrogen atmosphere, Joseph, Beatty, and Bitsianesl found that the zone of calcination advanced at substantially a constant rate at a given temperature. The purpose of this paper is to show that their data indicate at least two processes occurring when the above carbonates decompose. It is suggested that there are two processes occurring temperature range and the other the limiting process over another temperature range. The data of Joseph and co-workers have been extended by use of the Arrhenius equation, Eq. 1, a relation beween the velocity constant k of a reaction and the absolute temperature T.

Jan 7, 1954

I TOLD you before that four things are necessary in addition to good judgment for one who wishes to practice the art of casting well. The first is to make the moulds and to have the furnace well made, the wood of a good kind, dry and seasoned, and the material disposed to melt. I have given you enlightenment on all these in detail, and on the last point as well, as you can see in the discussion on the alloys of metals where, among other things, I told you a good deal about those of copper. Therefore I wish to say but little about them in this chapter, but in order to follow the order promised you, I tell you that when you can, and if the labor or expense does not displease you, you should always alloy the whole quantity of the metals that you wish to put into one work and should make them into cakes of one kind. For, in addition to being more conveniently arranged in the furnace and mire easily handled, they all melt at one time and with much less work than they would if they were in pieces of different kinds. It is necessary to give corruption to copper, for if you decided to melt fine copper by itself in a reverberatory furnace your soul would burst before you had any honor therefrom. Then, if you wished to cast a fine thing from it, it would not succeed because it is dot fluid, on account of its viscosity; and if it should succeed, it would be all full of holes, like a

Jan 1, 1942

By Thomas T. Read

IN reviewing the field of mineral industry education last year reference was made to recent assertions, mostly emanating from sources not in a position to know the facts, that mining engineers as a class are disappearing. Attention might also then have been called to a statement that appeared in Engineering News, August 11, 1892 (p. 130), ". . . the great absolute decline in number of mining graduates, which last amounts almost to a complete abandonment of mining engineering as a distinct branch of study." Evidently we outrank opera stars in the number of farewell appearances we are able to make; 43

Jan 1, 1936

By R. C. Canby

JUDGE GRANT, in a delightful satire of his, says: "Boston is a state of mind." I think that this same statement might well be made of the metallurgy of lead. I was particularly impressed with this when about thirteen or fourteen years ago I prepared a paper on "Development of the American Water- jacket Lead Blast Furnace." Dividing the time, as I did into ten-year periods, from the commencement of lead smelting at Eureka, Nev. (1870), and showing the tendency for each of the five decades it was evident that the progress had been through a succession of states of mind from the rule of thumb through the ultra scientific, or from what I might call the slag type period up to the present highly developed art. Conservatism has been characteristic of the metallurgist. This may have been most natural, especially with the lead metallurgist, the development of whose art was so entirely in the custom smelting plant, where the metal contents of his ores were paid for in cash and therefore excessive metallurgical losses could mean nothing short of financial bankruptcy. The metallurgist himself was held to a personal account, in these smelting plants. It was the metallurgist who was accountable. In the concentrating plants, if undue losses occurred remodelling of the plant was discussed, but if there were excessive metallurgical losses in the custom smelting plant, a new metallurgist was considered as the remedy. For this reason the tendency was to adhere to recognized practice and to be wary of unusual methods, using the word unusual in the sense in which it is used in Article VIII of the Constitution of the United States, as to punishments and modes of death. This conservatism of the metallurgist was reflected as other branches of metallurgy were developed. We have heard of the wonderful development of flotation, but it had to be introduced over the dead metallurgical bodies of its opponents.

Jan 1, 1926

By James Herbert Bartlett

The MANUFACTURE of Iron in the PROVINCE of Quebec. The St. Maurice Forges.—The deposits of iron-ore in the St. Maurice district, in the rear of Three Rivers, were probably known to the Indians and .Jesuits, but it is not till 1667 that any discovery is reported. The affairs of the colony were then in the control of the " West India Company," who amongst other monopolies had a right to all mines and minerals." Specimens of the iron-ore were examined in Quebec. in 1668 by the Sieur la Potardière, who reported unfavorably on them. In 1671, Louis de Buade, Comte de Frontenac, was appointed governor of La Nouvelle France ; and in the original manuscripts relating to his administration some allusion is occasionally found to the St. Maurice iron mines.? In a letter to the Imperial Government, dated 2d November, 1672, he says: "The iron mine of which I have already spoken is of great consequence. I have visited it myself, in order that I may be enabled to give a more accurate account of its nature. I am gratified to learn that another mine has been discovered in Champlain, which is much richer than the Cap de la Madelaine mine, and the ore is in greater

Jan 1, 1886

By AIME AIME

AS a new departure the annual business meeting was held at 4 p. m. on Tuesday, Feb. 16, instead of in the morning, as previously. The retiring President, Robert E. Tally, called the meeting to order and briefly spoke of the large measure of success that had been attained in balancing the budget of the Institute in 1931, so that, although receipts had declined over $26,000 compared to the previous year, expenditures had come within $3,000 of income. He referred in complimentary ,terms to the work of the committees on Membership, Admissions, Papers and Publications, and MINING AND METALLURGY, from which more would be heard late:. He also announced that a large and important committee on economics has been under consideration, and will be announced later. As an evidence of growth it was noted that a new Division, Mineral Industry Education, had been organized just an hour previously.

Jan 1, 1932

Montreal, April 6-7. "Resilient" and "bullish" were the terms used by R. D. Mushlitz of Asarco and K. C. Hendrick of Noranda Sales Corp. respectively, to describe the near term prospects for lead and zinc. The two men delivered their predictions at a joint meeting of the Lead Industries Association and the Zinc Institute held here. In speaking before a packed audience, Mushlitz insisted that "the lead industry is far from the sedentary one which many would have us believe, and although it may be slow and tortuous at times, . . . it is a viable and progressive industry which won't give up easily to the various pressures. . . . and, in the long run, will prevail."

Jan 5, 1972

By A. C. Stevenson

IN OUTLINING the various steps taken and the exigences met during the time of unwatering and rebuilding the burnt top equipment at the Hecla mine, the major portion of the detail is omitted and a general description of the experience only is given. All the electrical power lines were out of commission, as were the mine feeder cables. The first effort, there- fore, was to restore electrical connections. The Washington Water Power Co. immediately put a crew to work restoring the power line, it being necessary to rebuild about 4000 ft. of 66,000 volt transmission and about 2000 ft. of 2200 volt feeder. This work was rushed and power was again available at the mine sub- station about 26 hours after the fire. During the same time temporary lighting lines were strung and transformer equipment obtained, so that when electrical connection was resumed the lights were turned on and the dump well lighted that night.

Jan 1, 1924

By A. B. Parsons

LAST YEAR (1934) saw the completion of a ten-year program of reconstruction and modernization of the world's largest lead- smelting plant, that of the ' Broken Hill Associated Smelters Proprietary, at Port Pirie, South Australia, which has a capacity for smelting and refining 220,000 (short) tons of lead per year. It deals with the entire output of lead concentrates from the famous Broken Hill district in Australia, being owned .jointly by the three leading companies: North Broken Hill, Broken Hill South, and the Zinc Corporation. These companies, together with the Sulphide Corporation, are credited with a production of 198,000 tons of lead in 1934. When one says regarding any metallurgical plant that modernization is "completed" he should add "for the moment." Development in the art of metallurgy and in the equipment used never ceases; that which seems close to the last word today is likely to be obsolete in a few years even in a process so well standardized as smelting and refining lead. However, the reconstruction at Port Pirie has altered the procedure materially. More im-

Jan 1, 1935

By Persifor Frazer

I DESIRE to say that, owing to the number of papers which have been more or less crowded at this session of the Institute, and the fact that, as one of the Local Committee, I have the distinguished honor to feel somewhat like one of the hosts, I should not tax the patience of members at this late hour, but would have my paper read by title were it in any way possible to do this. But the task I have set myself this evening is to present to the eyes of the members of the Institute certain objects which have occupied more or less of my time during the last eighteen months or two years. The objects I allude to are some of the igneous rocks of this country, which, until quite recently, have been less understood than any others. It will be well known to some of the members that some of the cooled lavas of a previous age of our planet, when not directly coarsely crystalline and granular, were considered and spoken of as " natural glasses," or perfectly uncrystalline, vitreous, or hyaline masses of matter. Among the first results of the use of the microscope was the dispersion of this fallacy. Sir David Brewster, Mr. H. C. Sorby, and William Nichol (the discoverer of the celebrated calcite prism, which bears his name), had, with greater or less success, examined sections of various rocks and minerals, both by transmitted and reflected light, and also in the form of powder. But, until the genius of Vogelsang undertook the subject, these investigations had no permanent value, nor did they constitute an independent line of mineralogical and geological research. Since the close of his labors, by Vogelsang's premature and much-lamented death, the subject has been made one of renewed interest by his brother-in-law, Ferdinand Zirkel, as well as by Rosenbusch, Tschermak, and many others abroad, and at home by the commencement of a systematic study of the traps of Connecticut by Messrs. E. D. Dana and G. W. Hawes, of New Haven, and by the splendid set of described sections of the traps of the West which have been furnished by Zirkel to illustrate Clarence King's report. I had the honor of presenting a large number of thin sections of our traps at the Washington meeting, for the inspection of the members, with the aid of a table microscope belonging to the Smithsonian Institution. Here I propose to project these sections upon the

By Joseph L. Jernegan

The Whale Lode occurs in the main range of the Rocky Mountains, Park County, Colorado Territory, at Hall Valley. It has been opened up and worked to some extent by the Whale Mine, situated some 11,300 feet above the level of the sea. The mine, with 700 feet of the lode on either side of the discovery shaft, is the property of the Hall Valley Silver-Lead Mining and Smelting Company. The adjacent country rock is a compact, fine-grained gneiss; its general strike is about north and south, dipping steeply to the west. In the immediate vicinity of the mine, the strata are very nearly vertical. The gneiss incloses numberless veins of a reddish granite, in which the feldspar largely predominates over the quartz and mica, the latter oftentimes being scarcely perceptible. As a general rule these granitic veins seem to more frequently follow the lines of stratification of the gneiss than otherwise. They are of varying width, some large, some small; the larger are from 5 to 6 feet wide. Gash veins of feldspar and quartz are also of very frequent occurrence. The general trend of the lode is about northeast. and southwest, intersecting the country rock at about an angle of 45 to its stratification. It dips to the northwest at an angle of 65. I am unable to state accurately how far this lode has been traced upon the surface, but it is at least well known to extend entirely through the mountain upon which the mine is situated, and is traceable over the ridge by a hollow extending for some distance along the surface, in which the lode crops out. This hollow in the surface rock has probably been formed through decomposition of the vein matter by atmospherical influences. The width of the crevice is variable, generally between 5 and 10 feet; the pay vein varies from an inch, or less, to 36 inches. The vein is generally accompanied both on foot and hanging walls by a whitish, semi-decomposed fock, composed of quartz and decomposed feldspar, and in some places—where the process of decomposition has not reached as advanced a stage—a lightgreenish or black mica. This rock, therefore, is in places composed of all the constituents of gneiss, and is undoubtedly nothing more or less than the same in a decomposed condition. It is often very strongly impregnated with iron pyrites, generally crystallized in minute cubes, and it is probably owing to the presence of this min-