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By Dan E. Lewis, William E. Saegart

Similarities of certain geologic and mineralogic parameters are recognized among the various Philippine porphyry copper deposits. Lowell and Guilbert3 described a model of the typical porphyry copper deposit as the result of comparing numerous Western Hemisphere occurrences. Many of the characteristics of the Philippine porphyry copper deposits differ from the model developed by Lowell and Guilbert. A model of the typical porphyry copper deposit is presented and the characteristics of the Philippine model are compared with those of the Western Hemisphere model. Estimated Philippine copper production in 1975 was 242 446 mt. The total in 1948 was 2091 mt. This represents a 116-fold increase in copper production during the 28-yr period. The Philippines now rank seventh in total world production of copper.

Jan 1, 1978

I. PRESIDING OFFICERS. At all Business meetings of the Institute the President, or, in his absence, the Vice-President, or, in the absence of both of them, any other member of the Board of Directors to be chosen by the meeting, shall preside. At all other meetings of the Institute the President of the Council or, in his absence, one of the Vice-Presidents, if present, shall preside II. ORDER OF BUSINESS. At each Business meeting of the Institute the order of business shall be as follows 1. Reading of minutes of preceding meeting. 2 Report of the President. 3. Report of the Treasurer. 4. Report of the Secretary. 5. Election of Directors. 6. Election of Members of the Council. 7. Reports of Standing Committees. 8. Reports of Special Committees. 9. Special Orders 10. Miscellaneous business. This order of business may be changed by a vote of a majority of the Members and Associates present in person or by proxy. The usual parliamentary rules shall govern all meetings of the Institute except in cases otherwise provided by the Constitution or the By-Laws. At all sessions of the Institute other than business meetings, the order of proceedings and the time of adjournment, shall rest in the discretion of the presiding officer

Jan 1, 1917

By Tell Ertl

TODAY'S mining industry is witnessing a transition in labor utilization. The drill-jumbo operator, the mucking-machine operator, the blasting crew, the scaling and timbering crew are all specialists. The all-around miner is rapidly disappearing. As mechanization has resulted in a higher order of underground skills; specialization of labor has been a natural consequence, as has the need for more supervision and engineering. Mines now are cleaner, neater, safer, and have a greater productivity per man-shift than ever before. Nothing spectacular like the continuous miner has yet come to the underground metal mines, but t a gradual improvement in methods, equipment, and technical knowledge is achieving the increased efficiency. With the exhaustion of the rich ores and large profits and who-cares-about-the-costs, mining has become a business; that of producing low value ores at costs below selling price. Charles A. Chase, patriarch of Colorado mountain mining men, manager of the Shenandoah-Dives, was one of the first to preach and prove his preachings that mining is a business. He has been mining a lead-copper-zinc-gold-silver ore, much from elevations above 1.3,000 ft, for a quarter century without a shutdown.-The ore is of such low value that most engineers and investors still would consider it foolhardy. Yet he has kept Silverton, Colo., alive, has paid wages without a lapse, has produced $25 million of new wealth and maintained a steady return to the investors. This type of responsibility is increasingly apparent in the mining business and is one feather that can be worn proudly. .Much emphasis is being placed on improving, the productive mining operations-breaking, loading and transportation. Breaking in underground metal mining is done by drilling and blasting. To the writer's knowledge, no chain or rotary-type machine has been developed for mining strong, abrasive rock. Drilling Percussion drills are still the standard drilling machines underground. Diamond drills, that: were the rage a decade ago for drilling long holes, are being superseded by the rock drill. The development of the hard abrasion-resistant carbide bit permits full-gage long holes to be drilled by percussion drills at a lower cost than diamonds. The change in the use of percussion drills is chiefly in the method of mounting. The column and arm are disappearing and the jackleg and rubber-tired or track-layer jumbo mountings are taking its place. At the Homestake mine .lightweight jackhammers mounted• on pneumatic legs using 7/8-in. hexagonal drill. rods and 1 1/2-in, tungsten-carbide detachable bits have been found more portable and maneuverable. They have less air consumption, lowered, dynamite consumption, and more footage and tonnage per man-shift than with 3 1/2-in. drifters on a column mounting. Drills now are mounted on longer feed carriages, drilling up to 20 ft without changing steel. These mountings result in great savings because the driller can set up quickly, drill the entire depth of the hole without changing the drill rod or bit using carbide and one-use bits, and can move his machine quickly to the next hole. One man to the machine is becoming general practice. The result is longer rounds rounds drilled at a lower cost than the previously used short rounds. A jumbo developed in the Tri-State can be extended to mine ore left in the roof up to 65 ft above the floor. Drill-rod life was formerly considered to be about 250 min of actual use. The increase in the drilling time per rod per day has gone up considerably with the development of the jumbo and the long-feed carriage, resulting in which is apparently more rod breakage., Consequently, a great deal of research is being done in the attempt to develop an alloy-steel rod with longer service life to offset the greater cost. Some reports indicate that alloy steel or Swedish steel results in cheaper drilling than conventional drill rod. However, several tests have shown only slightly increased life for alloy drill rod. Undoubtedly, the blow of the rock drill, the length of the drill rod, and the resiliency of the rock being drilled are important factors in the life of drill rod, so it follows that alloy steel might work well in some mines and result in no savings in others. The bit forged on the drill rod is seldom encountered and steel detachable bits are not as common as in the recent past. The one-use bit is gaining popularity because of. the difficulty in rehardening reconditioned steel bits satisfactorily. It is thought that the, carbie-insert bit is most applicable to drilling hard 'rock' where the steel bit is unable to drill out a full change, for instance, in extremely abrasive

Jan 1, 1952

By D. L. McElroy

SAFETY in coal mining received especial attention by the public in general and the mining industry in particular during 1940 and early in 1941, owing primarily to the six explosion disasters which occurred last year with a total of 276 fatalities. This was the largest number of fatalities due to explosions in bituminous coal mines since 1928, when 347 lives were so lost. But facilities due to explosions have had a definite decreasing trend since 1907, in spite of bad years such as 1917, 1924, 1932, 1937, and 1940. Although the upswing in explosion fatalities in 1940 is lamented by all, none will admit it represents a trend and it will serve mainly to stimulate ways and means of further reducing these disasters.

Jan 1, 1941

By Francis A. Thornson

WITHOUT desiring to perpetrate an Irish bull I think we may safely say that the major developments of the year in mineral industry education have taken place outside of the field itself. I refer to the remark- able and-to us of the Education Di- vision-most gratifying growth which is taking place in Institute consciousness regarding its responsibility for the recruitment and adequate training of student personnel and for the successful bridging of the difficult gap between graduation and achievement of professional status. Outstanding in this respect is President Jackling's interest in the students and schools of the mineral industry. Recalling his own hard struggle to ac- quire a technical education, Mr. Jack- ling is evidently anxious to smooth the path for the youngsters of this generation. Witness his splendid gift to the

Jan 1, 1939

By George W. Pawel

OWING largely to its value as a toughener and strengthener of steel for both industrial and military purposes, nickel is playing, an important role in the current war. It is fine of the metals in which the Allies enjoy a definite edge over the Axis nations and this time there is no place to which the Germans may send another submarine "Deutsehland" and expect to pick up a cargo of nickel to replenish their exhausted supplies. Total world nickel production thanks almost entirely to the expanded operation of the International Nickel Co. of Canada at Sudbury must now be at the rate of around 175,000 tons a year scarcely more than 5 per cent of which is accounted for by Germany, Italy and Japan. This represents more than four times the world output at the end of the first World War.

Jan 1, 1943

By Charles Will Wright

ITALY is by- far the poorest in mineral resources of the so-called great pou7ers of Europe. Before the World War this shortage was not so serious as the essential minerals that could not be mined domestically at a profit were bought in the world markets. In those days tourist trade and remittances from Italians abroad helped to provide Italy with foreign exchange. During the World War, when certain mineral products were scarce and when prices rose in some instances to several times normal, the Italian Government began to regulate consumption and imports. It was not until later, when the Fascist regime established the corporate state, that Italy seriously considered adopting a of self-sufficiency. Private industry was grouped under separate corporations, for the principal industries; including mining and metallurgy and the heads of the large producing companies, became members of these corporations. Industrialists were thus able to regulate their own affairs and to advise the Government as to the measures necessary to meet domestic or foreign trade demands upon their industry. Labor was or-

Jan 1, 1939

By John B. Miles

THE present period of depression in the iron industry, with the resultant close approximation of the cost of production to the selling-price of pig-iron, should make the discussion of this subject at this time not only interesting but, profitable. It is possible that it may result, in the collection of data, which when added to those set forth in this paper will clearly indicate the influence of the rate. of driving a blast-furnace upon its fuel-economy. The question is not whether an excessive rate of driving (meaning a rate definitely in excess of the average rate in the United States) results in, an increase in the fuel-consumption, but rather whether a rate considerably less than the average does not result in a marked decrease in the fuel-consumption. The commercial and metallurgical sides of. this problem must be kept separate. With a large margin between the cost of production and the selling-price of pig-iron, and a plant already in operation, it is frequently profitable to sacrifice a couple of hundred pounds of fuel per ton of pig-iron in order to secure the greater gross profits resulting from a larger tonnage. When this margin decreases with a plant in operation, or when the determination of the size of a new furnace intended for a certain production . confronts the management, a clear understanding of the effect of the rate of driving upon fuel-economy becomes necessary. If it be granted that slow driving leads to low fuel-consumption, it should he borne in mind in the design of a new plant for the production of a certain tonnage that the adoption of an economical rate of driving increases only the size of the furnace proper, whereas, due to the decrease in quantity of blast required on account of the decrease in fuel burned, the stoves, the blowing-engines, the boilers and the piping may be de-

Sep 1, 1908

By D. B. RUSHJIORE

(New York -Meeting, February, 1912.) TORCHES were used by the early Romans for mine-lighting, and these were followed by open lamps or earthen jars filled with tallow or oil, and later by candles. In early coal-mining, explosive gases seldom occurred, and, if they were encountered, the danger of explosion was materially diminished by the absence of any ventilating-system and the consequent insufficient circulation of air to form with the methane an explosive mixture. As the art advanced, the danger of fire-damp became more apparent, and methods for testing the air were resorted to as early as in the fifteenth century. The method of testing consisted in lowering a clog in a, basket down the shaft. As soon as he encountered fire-damp he would commence to howl, after which he was withdrawn, and a leafy bush was fastened to the end of the rope and run rapidly up and clown the shaft. This so disturbed the accumulation of gas as to cause it to rise out of the shaft. Later this odd method of testing was improved upon through the discovery that a light inserted in a body of fire-dam p would produce a blue flame. Candles were used for this purpose, and, when fire-damp was thus discovered, brushing or some other primitive method of fanning was resorted to for driving out the gas. In some instances the gas was burned away, regardless of the danger thereby incurred. A man, wearing a well-moistened coat and a mask with glass spectacles, descended in the mine a few hours before each shift. With a long stick, to which was fastened a burning torch or candle, lie would crawl on the floor with the stick so raised that the light would sweep the roof and ignite the gas which it encountered. In this position the flame of the explosion would pass over him, after which he would retreat from the gases resulting from the combustion. The occurrence of serious accidents resulted in

Jul 1, 1912

By AIME AIME

ONE hundred and eighty-three A.I.M.E. members, W. S. Morris with an excellent technical program, John Suman, "oil" President of the Institute, and a Texas norther blew into Dallas for the fall meeting of the Petroleum Division at the Adolphus Hotel, Oct. 16-18. and the most successful result will give future meeting committees a high mark to equal. People were still talking of the terrific heat the week before and it was quite noticeable that with the lowered temperatures, the members were in fine fettle for the technical sessions. The total attendance on Friday noon was

Jan 1, 1941

By AIME AIME

THE petroleum economics session," held on Wednesday morning, Feb. 20, 1929, presided over by Campbell Osborn, chairman, proved to be of un- usual interest and resulted in serious and constructive discussion of the papers presented. The first paper on the program, "Gasoline Economics and Refinery Operation," was by H. J. Struth, petroleum economist of the Gulf Publishing Co., Houston, Tex. While this paper was intended to cover the re- finery situation, it also presented the author's reasons for believing that the oil producer should give cognizance to gasoline demand as a most reliable barometer by which to parallel the production of crude petroleum. The discussion which followed brought out some interesting points in connection with the immediate outlook for the industry as a whole during the present year. Some advanced the opinion that, regardless of the out- come of proration efforts, the refiner is in a position to conduct his operations on a reasonably profitable basis, provided that he exercises control over them. This would mean running less crude and resorting to wider utilization of cracking to produce the gasoline demand. Thus, if the refiner uses diligent care in scheduling his still runs, the producer will be obliged to carry over a large stock of crude this year, unless he is able to keep production below the limits prescribed by the demand for gasoline.

Jan 1, 1929

By W. F. NETZZEBAND

THE long-hole drill has been used for prospecting underground in the tri-State district for several years, and its value has been pretty thoroughly proved. An attempt was made to get a statement of their experience with the machine from all the operators who were known to have used the machine. The majority of them replied to the questionnaire so that this paper is practically a summary of the experience of the district, together with some practical details taken from the experience of the Eagle-Picher Lead Company. When the drill was first used by the Eagle-Picher Lead Co., it was put in low headings and was mounted on a cross-arm supported by two drill columns. This was found to be a rather awkward method of mounting, because fairly long moves were made and the same drill columns could not be used on any two successive set-ups. The machine was later moved to a mine with high headings so that this type of mounting was found to be impractical. A heavy tripod was tried and found satisfactory, provided care was taken to see that the set-up was solid. The Evans-Wallower Lead Co. and the Century Zinc Co. report using the double post set-up, but the headings are low in these mines. The Commerce Mining St Royalty Co. first used the double-post mounting in high headings by cutting a niche in the wall and setting the post in it. This proved to be a slow and expensive method and was later abandoned for the tripod. The Federal Mining & Smelting Co. has used a tripod throughout its operations. Great care must be taken in using the tripod to see that the set-up is solid. Wherever possible it is advisable to sludge in the legs and let them set a short time before the machine is put into use. Where high bottom is encountered the Eagle-Picher operator found it advisable to drill jack- hammer holes in the bottom and drive the legs into them.

Jan 1, 1930

By H. M. Wilten

THIS article presets a view of a problem encountered in petroleum refining in the deterioration of equipment used in condensation of vapors and cooling of liquids. Discussion is limited to the problems of shell- and tube-type exchangers and condensers. In this service shell- and .tube-type equipment is gradually displacing other types and, for this reason, its economic importance ill oil-refining practice is also increasing. Considering oil - refinery practice during the last two decades one can readily see many important improvements in the apparatus used. Briefly, the present equipment is safer, more efficient, and Ignore economical. Improvement in apparatus used for the condensation of distillates has, in my opinion, been less than that in other essential distilling apparatus. So it is hoped that this discussion will stimulate research among the producers as well as among the consumers of this equipment with a view to ameliorating this condition.

Jan 1, 1937

By R. G. Green, R. L. Dowdell

LEAD POISONING as a result of eating lead pellets deposited in marsh areas is a cause of high mortality among ducks, geese, and other waterfowl ingested lead shot become trapped in the gizzard with gravel and are slowly ground away by the grit. Absorption of lead as it passes through the intestine in a finely divided state produces severe lead poisoning which is usually fatal. Ducks and geese with lead poisoning develop first a typical green diarrhea. Later, paralysis of the wing muscles prevents flight. As the poisoning continues with further grinding of the shot trapped in the gizzard, increasing paralysis reduces the bird to helpless-

Jan 1, 1937

By AIME AIME

MILLING called for four sessions and a luncheon and covered broad ranges from speculative theory to basic practice, and from coal to gold. An attractive and profitable feature was the "get-together" of "coal preparers" and "ore dressers" for mutual discussion of their common problems. The first event was the Milling Luncheon in the Engi¬neers' Club on Monday. A concentrated group of high¬grade appeared and many matters were discussed, but only two called for official action: The meeting unanimously recommended the use of the Tyler standard sieve scale as against any new scale, and also the adoption of micron designation for fine particles in place of decimals of an inch or millimeter, or theoretical mesh size. The real sessions began on Monday afternoon with a menu of Mineral Physics for the ore dresser, metallurgist, geologist, physicist, et al. Four papers by the staff of the U. S. Bureau of Mines dealt with the chemical and physical aspects of mineral structure as revealed by the first two years of research to date. A fifth paper by Dr. M. J. Buerger correlated to the foregoing the knowledge of "The Lineage Structure of Crystals" and finally a sixth paper was a progress report of further developments of the last year in explosive shattering of minerals by the U. S. Bureau of Mines.

Jan 1, 1933

By Alexander Anderson

TABLES showing the drift and inclination of wells surveyed in the years 1924 to 28' and in the year 1929' have already been published. Each of these tables included a little over 1,000,000 ft. of rotary hole. In the year 1930 the table -shown-in . Fig. 1, comprising, the results of surveys .of 1,030,344 ft. of hole and representing 11,642 individual survey readings, was compiled. For that purpose we selected 'I only wells that had been drilled in California during that year. The footage of Fig. 1 differs from the two earlier tables in that the wells were all drilled in the year 1930. In the earlier tables, the footage shown was surveyed in the years designated, but some of the wells were drilled in earlier years.

Jan 1, 1931

By E. DeGolyer

USE of geophysical methods as an aid to prospecting for new oil pools and in the exploration of already discovered pools continued to increase and reached a new high during 1934. As in previous years, the scene of greatest activity was the Gulf coastal plain of Texas and Louisiana. Seismic crews working by the reflection method increased from some thirty crews at the first of the year to forty crews at the end. An increased demand for torsion balance work at the beginning of the year occurred and practically all available instruments were put into service. Some thirty crews with approximately eighty balances continued throughout the year. Both the pendulum and gravimeter methods of gravity surveys registered their initial successes and equipment was increased from five to seven pendulums and from one to three gravimeters during the year. Approximately five magnetometer parties continued to work throughout the year. No surface surveys by the electrical method are known to have been made. Outside of coastal Texas and Louisiana the chief geophysical work

Jan 1, 1935

By G. R. Wilms

A study has been made of the structural changes in polycrystalline high purity aluminum during the tertiary stage of creep under conditions of constant tensile load. It appears that there is no basic modification in the particular mechanism of deformation that characterized the preceding secondary stage of creep, but that the changes in crystalline structure produced during the tertiary stage are only a consequence and not a cause of the accelerated strain. Intercrystalline fissures were observed on entry into the tertiary stage, and these might supplement the accelerated rate of strain owing to local stress concentrations. There is evidence that the formation of these fissures may be associated with the presence of surface imperfections, and it is suggested that a more generalized treatment of the results may explain certain creep characteristics of commercial alloys. IN previous work'-4 a study was made of the changes produced when specimens of annealed aluminum were deformed at various temperatures and rates of strain, especially under conditions leading to creep under constant tensile load. It was shown that, as the temperature was increased or as the rate of strain was decreased, elements of the substructure produced within the grains became coarser, and with the strain rate constant at a given temperature, their size tended to an equilibrium value. The preliminary process of the breaking down of the grains into a substructure was identified with primary creep.' The subsequent equilibrium, condition was associated with secondary creep. The question then arose whether the tertiary stage corresponded to any further significant change in the substructure. The question is also of interest in view of the opinion, expressed for instance by Andrade,5 that the tertiary stage is merely an accelerated rate of strain due to the reduced area of section of a specimen under continuous tensile load, and the other opinion, as suggested by the observation by Sully, Cale, and Willoughby6 of a tertiary stage in com-pressive loading, that this third stage is a real effect in its own right. The object of this paper is to record some observations on the tertiary stage of high purity aluminum. Experimental Procedure The material was aluminum of 99.98 pct purity as previously used. The specimens had a rectangular section of l/8 x l/2 in., and extensions were measured over a 1 in. gage length. After machining to shape, the specimens were annealed to give a standard grain size of 0.2 mm and then electropolished. The general procedure involved metallographic and X-ray diffraction examination at progressive stages of elongation (marked by arrows on the curves shown in Figs. 1 and 2), the specimen being extended to fracture under constant load at a given temperature. The X-ray tests were made by the back-reflection method from a stationary specimen, using CoK radiation. The longer edge of the micrographs in the paper corresponds to the direction of applied stress. Results The previous work showed that, in the secondary stage of creep in aluminum, three basic types of structure could be developed according to the temperature and rate of strain. These were: 1—slip, which predominated at the lower temperatures and higher rates of strain and produced the finest and least perfect substructure; 2—cell structure, which superseded slip as the temperature was raised and the rate of strain decreased and which was characterized by a coarser and more perfect structure and an absence of slip lines; and 3—a stage termed "boundary microflow," which predominated at still higher temperatures and lower rates of strain when the cell size had increased and become comparable

Jan 1, 1955

By R. S. Bradley

WHAT are known as insulating firebrick are lightweight firebrick with low thermal conductivity designed primarily for use in direct contact with furnace gases. These are a recent development in the refractories industry, and are really an outgrowth of the type of insulating brick suitable for use behind refractory walls developed by the insulation manufacturers. To differentiate between these two types of brick, the manufacturers have recently agreed upon the use of the term "Insulating Firebrick" to apply to the type of brick suited for use in direct contact with furnace gases, and the term "Insulating Brick" for the type suitable for use behind refractory walls. Insulation was applied to steam pipes as far back as 1900. This was a low-temperature insulation, the most common type being magnesia blocks. The next development was applying insulation to the outside of furnace walls, a service which necessitated an insulating material of higher temperature resistance. Natural diatomaceous earth, both in the powdered and brick form, was used; this was efficient and is still used extensively for backing up refractory walls where the inner surface temperature of the insulation does not exceed 1600° F.

Jan 1, 1937

By E. B. BESSELIEVRE

THE great work of Gorgas in stamping out yellow fever in Panama during the construction of the Canal was one of the chief factors contributing to the ultimate accomplishment of the task, two previous attempts having failed largely through the demoralization of workers by epidemics of contagious diseases. Mining camps, rapidly constructed during the boom days of the rushes to new fields, have been frequent sufferers from typhoid when, as so often used to be the case, little or no attention was given to bacterial examination of the water supply or to the method used for disposing of the sewage.

Jan 1, 1930