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ASSETS Working Fund Assets Cash-unappropriated $62,41294 Members' 1951 dues receivable 14,336 98 Accounts receivable Advertising, publications and miscellaneous $43,22055 Less-Reserve for delinquent accounts 12,775 76 $30,44479 Petroleum Branch-Special Projects Fund¬ Advances re Petroleum Conservation Volume 5,37085 35,81564

Jan 1, 1952

Jan 1, 1966

By R. C. Allen, Ralph Arnold

The writers have no new system and no new principle of taxation to propose. The general subject of taxation is as old as governments are and as familiar to taxpaying Americans as the general thesis on the inalienable rights of man. We believe, therefore, following the committee of the National Tax Association, that improvement in the general conditions of taxation, including mine taxation, maybe brought about mainly through a better adjustment of known and tried principles and methods of taxing to modern complex forms of property and income, and that not much is to be expected from abandonment of experience for new ways and means, methods and principles, should anything new be discovered, which in our opinion is very doubtful. The committee referred to has constructed the general framework of its Model System of State and Local Taxation1 on familiar forms of taxing, by eliminating some that ' have proved bad, suggesting improvements in others, and adopting the best, leaving plenty of room for the accommodation of the general plan to the varying conditions of taxation in the several states. Unfortunately, the taxation of mines is dismissed by the committee with the statement that the subject has been reassigned for further investigation and report by a special sub-committee, frankly recognizing that the peculiar difficulties of this phase of the subject require special study and investigation. Much may be hoped for from the labor of this sub-committee if the problem is approached from the viewpoint of recommendations already published. In this paper, the writers state their opinion on some of the broader aspects of mine taxation with too little attention to the grounds on which they rest. Contrary to inclination space requirements compel them to resort to summary statements without adequate discussion for a satisfactory presentation of the whole subject. All they can do is to qualify the witnesses and record the testimony. The senior writer was introduced to the practical aspects of the subject of this paper in 1913, when, as State Geologist of Michigan, he was

Jan 1, 1920

By Chung Yu Wang

STUDY of two recent papers and a recent book leads one to raise anew the question-Why are certain regions of the earth more mineralized than others?

Jan 5, 1953

By H. S. Strouth

JAMAICA-bauxite and gypsum-but what else? J Does the Caribbean island have anything more to offer in the form of mineral wealth? One answer may be iron ore deposits which show enough promise to warrant exploitation in the near future by a company associated with Standard Ore & Alloys Corp. In addition, Jamaica is reported to have gold, silver, platinum, copper, lead, zinc, manganese, cobalt, and a great many nonmetallic minerals. Of these, only platinum has not been produced commercially in the past. Right now, Jamaican bauxite is getting most of the publicity, but not too long ago other mining operations were in progress. Lack of proper interest, insufficient roads, and scarcity of venture capital forced those mining properties to suspend production.

Jan 7, 1954

By Wallace W. Wilson

It scarcely is possible to read a new issue of any of the principal mining trade journals without noting some mention of a major new overseas mining venture with which one or more domestic companies are involved. These projects follow a fairly consistent pattern; most are large open pit mines with relatively low grade orebodies but huge reserves; the total price tag is in nine significant figures and half or more of the total cost is for infrastructure. West' notes that nearly $7 billion is being invested annually for new mining projects and the expansion of existing mining ventures in the free world. He anticipates that by 1975 such investments will reach the $10-11 billion annual figure and that in the period 1972-76 total capital requirements can be expected to aggregate around $45 billion. West estimates that 75% of the total capital will come from internally generated funds. Conceivably, a substantially higher percentage could be attributable to external financing, especially if the trend of recent mineral development in Canada and Australia is any criterion, and including local sales of equity as a part of the package.

Jan 7, 1973

Jan 1, 1958

By Luther M. Krupp

A 3 ½ -mile asphalt mixed mat haulage road joins American Smelting & Refining Co.'s El Tiro copper pit northwest of Tucson and its Silver Bell mill. Two-axle trucks operate continuously over the road- way but the asphalt top shows none of the wash- board wear usually seen on dirt haulage roads during use by heavy vehicles. The following data cover construction of this road, and results of its use by Asarco and Isbell Construction Co., the road's builder.

Jan 11, 1958

By James Norman

SEPARATION of minerals by froth flotation is rightly called an art. It can truthfully be said that no two ores separate in the same way. The difference in results obtained when natural and synthetic mixtures of minerals are separated is so great that such tests frequently have been worthless in attempting to select conditions in which a natural mixture will separate. With a few rare exceptions, the natural mixture is much more difficult to treat than a synthetic mixture, and a much poorer separation is obtained. Perhaps several experimenters have wondered why 10 or 20 per cent of a mineral being floated from an ore does not float and is different from the 90 or 80 per cent that is recovered. In experimental tests on pure sphalerite, observers1 have noted that varying amounts of sphalerite may be froth-floated with pine oil alone, the amount recovered in the froth depending apparently upon the source of the sulphide. The only explanation of results such as these, barring insufficiency of frother or time of flotation, is that the surface of the mineral floated is different from that of the mineral depressed. This difference often has been found to be caused by natural contamination of mineral surfaces, apparently brought about by weathering and exposure to natural solu-tions. There is virtually no rock that is absolutely unweathered. One of the writers had an exceedingly instructive experience in 1931 while working with United Verde copper-zinc iron sulphide ore in Arizona. Nonselective flotation of chalcopyrite and sphalerite away from some of the pyrite was all that could be accomplished. All known depressants produced only slight effect. Sodium cyanide showed some effect, but so much had to be used that only a small amount of chalcopyrite could be

Jan 1, 1939

Time Now For Thinking In these turbulous times a natural restiveness is created among the younger men of the mining profession. Many of them are veterans of World War II and the question is raised in their minds as to whether or not to go back into military service. There is time to think about this question now and it is advisable to do so in order that snap decisions may be avoided if war is declared.

Jan 2, 1951

By John C. Robison

INTRODUCTION Sensitivity analysis is a means of gauging the impact of individual risks on a financing. Key risks can occur in three time periods: - Feasibility, engineering and construction phase; - Start up phase (usually through completion); - Operating phase (post completion). If a company has agreed to cover these risks prior to completion, then less attention will be paid to the sensitivity of the project in the first two time periods. Since the operating phase of the project generates cash for both operations and debt service and generally does not begin until two to six years after the loan is signed, it is wise to look at scenarios other than the projected "base-case" scenario in order to determine the project's capability to operate successfully under a broad range of probable future events. Lenders are compensated at a fixed spread over their borrowing base and generally are not compensated if the project is successful beyond expectation. They are also subject to the loss of principal plus funding costs if the project performs below expectation. Because of this, lenders establish sensitivities around the parameters of conservative projections developed in the project feasibility studies and the cash flows resulting from these projections. The initial cash flow projections should demonstrate the project's ability to meet cash costs, debt service requirements (principal and interest), and still have sufficient cushion to cover contingencies such as strikes, price fluctuations, force majeur situations, etc. (See Schreiber, Chapter 10). The selection of the level of sensitivity analysis to be performed is the result of both objective criteria, including probabilistic analysis applied to the technical parameters, and, of equal importance, subjective criteria applied by the analysts, especially with regard to the economic and financial parameters impacting the project cash flows. RISK SENSITIVITY Assumptions used in the cash flow projections should be realistic. Risks identified by the lenders should be identified and cash flows prepared to assess whether these project risks are acceptable. Typical project risks include the following (see also Chapter 9): - Sufficient reserves - quantity and quality - Product price - Production level - Operating costs - Availability of energy and supplies - Transportation and infrastructure requirements and costs - Interest rate - Completion risks - Tax level - Political risks - Cost over-run risks - Operator experience - Management - Technological risks - Environmental permits and risks - Foreign exchange risks - Insurance coverage - Equity of sponsors - Inflation rate - Capital expenditure during project life In order to see the effect on the cash flow projections, each risk should be analyzed for its impact on the cash flow generating capacity of the project. Sensitivities can be examined to see if the resultant cash flow projection will meet the lenders minimum credit standards. 1.Reserve Sensitivity In general, lenders will not assume the reserve risk. However, it should also be noted that lenders receive loan proposals in which reserves range anywhere from proven to possible. Sensitivities are not generally run for various reserve levels and reserve estimates are either considered acceptable or not acceptable by the lenders.

Jan 1, 1985

By P. R. Sperry, P. A. Beck, J. Towers

Dahl and Pawlek1 found that electrolytic copper develops extremely coarse grains at 1000°C after about 90 pct reduction by rolling. This coarsening occurs only under conditions of penultimate grain size, deformation, and alloying which lead to the "cube" recrystallization texture.l,2,3,5 The peculiar angular shapes and straight grain boundaries of the coarse grains were noted by several investigator.1,4,5 On the other hand, coarsening in Fe-containing aluminum or in AI-Mn alloys8 does not depend on a "cube" (or any well developed) recrystallization texture. It is true that increasing deformation by rolling, and, therefore, an increasingly well developed re-crystallization texture, are associated with decreasing incubation periods of coarsening.6-7-8 Nevertheless, coarsening readily develops in aluminum even after only 30 pct reduction by rolling, where the recrystallization texture is very weak.6,8 Also, coarsening was observed by Jeffries9 many years ago in sintered thoriated tungsten, which presumably has no preferred orientation. In all these cases coarsening is associated with grain growth inhibition by a dispersed second phase.8,9 The annealing temperature has to be suficiently high to overcome the inhibition at a few locations. But if it is too high, growth starts at many points, and the resulting grain size becomes much smaller.9 Normally, the coarse grains are more or less equiaxed, and the boundaries have a typical ragged appearance.6.8 Cook and Macquarie4 demonstrated that, in addition to the texture-dependent coarsening previously found at 1000°C,l electrolytic tough pitch copper may also coarsen at 800°C after 50 pct reduction by cross rolling. The coarse grains formed under such conditions have rounded shapes and ragged boundaries, like those in aluminum. When the annealing temperature is higher, the tendency for their formation decreases. All these observations suggest that the coarsening at 800°C is associated with inhibition by a second phase. Actually, coarsening at 800°C after 50 pct reduction by cross rolling was observed only in tough pitch copper,4 which contains Cu2O particles. On the other hand, the texture-dependent 1000°C coarsening occurs in both tough pitch and oxygen-free copper;4 it does not appear to depend on the presence of a dispersed second phase. However, the interpretation of the 800°C coarsening in Cu after 50 pct rolling as an inhibition-dependent process, similar to the coarsening in A1-Mn alloys, is somewhat weakened by the fact that this coarsening was reported4 to occur only after cross rolling, and not after straight rolling. It was, therefore, decided to re-examine this question. A 1 in. diam electrolytic tough pitch copper rod, No. 2 hard drawn, was annealed for 20 min at 700°C, rolled to 0.5 in., annealed 10 min at 700°C, and straight rolled to 0.064 in. It was then given a penultimate anneal of 20 min at 500°C and it was cut into four sections, which were given final reductions by straight rolling as follows: A 30 pct reduction of area B 50 pct reduction of area C 70 pct reduction of area D 90 pct reduction of area Specimens cut from the four sections were finally annealed at 800°C in an oxidizing atmosphere. Strip A remained fine grained up to 10 hr, but the specimen annealed 12 hr consisted of only 2 large grains. Strip B had a few scattered large (1/2 to 3/4 mm) grains after 1 min, although the balance of the specimen consisted of fine grains of about 0.02 mm. After 5 min there were several 10 to 15 mm grains present, and after 1 hr strip B was completely coarsened. The coarse grains had the same characteristics (see Fig 1) as those obtained by Cook and Macquarie at 800°C after cross rolling. Strip C had several grains of 0.05 to 1 mm after 1 min, but it was still largely fine grained after 12 hr. After 48 hr it consisted entirely of grains of about 0.5 to 4 mm, with an extraordinarily large number of twin bands. Strip D remained com- pletely fine grained after 4 hr at 800°C. These results indicate that, in the deformation range of 30 to 70 pct reduction, the incubation period for coarsening as well as the rate of growth and the final size of the coarse grains decreases with increasing deformation. Similar

Jan 1, 1950

By J. G. Thompson

IRON, iron everywhere, but hardly a particle of pure unadulterated iron for the metallurgist to use as a base for the protean characteristics that he develops in the alloys of iron-the modern steels. Iron, next to aluminum the most abundant metal in the crust of the earth; one of the oldest metals known to man and serving him as the most indispensable metal in both war and peace; yet man's knowledge of its properties is based on specimens that are not pure and hence probably differ considerably in their properties from the truly pure metal. Purification of iron has brought about startling changes in its electrical and magnetic properties and has modified its behavior in changing its crystal form with temperature, the basis of the heat-treatment of iron. So both the research metallurgist and the metallurgist of the steel plant are intrigued by the possibilities that might unfold were 100 per cent pure iron available in sufficient quantities to determine its properties.

Jan 1, 1940

Jan 1, 1957

By Donald L. Katz

Charts for predicting the pressure to which natural gases may be expanded without hydrate formation have been prepared for gases of even gravity. Pressure-temperature curves for hydrate formation were established for gases having gravities from 0.6 to 1.0. These curves and the thermal behavior of the gases during free and adiabatic expansion were used to prepare the charts for estimating the permissible expansion of natural gases without hydrate formation. The problem was solved by L. F, Albright, W. T. Boyd, J. J. McKetta, G. Martin, P. Poettman. and A. P. Snyder.-, who are first-year graduate students in the department of Chemical and Metallurgical Engineering at the University of Michigan. This paper is essentially a summary of their results. Prediction of Conditions for Hydrate Formation in Natural Gases Each natural gas under a given pressure will form solid hydrates at a corresponding temperature provided sufficient water is present.1-5 The temperature of natural gases below about 5000 lb. per sq. in. decreases when the gases are expanded freely.6,7 This decrease in temperature may cause the expanding gas to enter the region of temperature and pressure at which hydrates will form' The final pressure to which a natural gas may 'be expanded without hydrate formation depends upon the initial temperature and pressure and the gas composition. This paper presents charts that give the final pressures to which gases of gravity 0.6 to 1.0 at given initial temperatures and pressures may be expanded without formation of hydrate. Hydrate-forming Temperatures and Pressures as a Function OF Gas -Gravity Experimental data of pressure versus temperature at which solid hydrate will form, provided sufficient water is present, are available for a series of gases.2,3 A method of predicting the pressure-temperature curve for a given gas composition has been reported.' The solution to this problem requires that these curves relating pressure to temperature be established for gases of given gravities.

Jan 1, 1945

By F. L. Wolf

THERE is a tendency on the part of practical foundrymen to accept with reluctance the results of tests on sands, binders, and. such materials made in the chemical laboratory alone. They feel that such tests frequently emphasize and measure properties that are of minor importance and fail to take account of characteristics that are important in determining the value of the material in actual practice. Experience seems to indicate that the most thorough and conclusive, test for any new foundry material is an actual run in the foundry alongside of a standard material of known value. Such a test, however, involves certain difficulties and necessitates certain precautions. It is not always easy to obtain a fair trial for a new material. We all have certain prejudices, which unconsciously affect our judgment to a marked degree. A practical test frequently involves so many workmen, each of whom reacts in a different manner to the test, that; the personal equation becomes very, complex and the true results of the test are obscured. There are times, too, when a thorough experimental trial of a material would interfere too much with the rush of work in a department or would hazard the quality, of the product to such an extent as to make it inadvisable. Under such conditions a laboratory test is advisable before the material is sent into the foundry. These tests should be made as practical as possible and so closely related to foundry practice as to give a true index to the value of a, product for the purpose desired. Core sands and molding sands are as numerous "as the sands of the sea" and vary as much in quality. Old sources of supply are continually failing and new ones must be opened, so that we must continually search for new and better grades of sand. During the past year, the Ohio Brass Co. has developed tests for sands', cores, and binders which bear a close relation to the particular use to which these materials are put in

Jan 9, 1920

PRESIDENT OF THE COUNCIL. JOHN HAYS HAMMOND NEW YORK, N. Y. (Term expires February, 1909 ) VICE-PRESIDENTS OF THE COUNCIL SAMUEL B. CHRISTY BERKELEY, CAL. JOHN A. CHURCH NEW YORK, N.Y. PERSIFOR FRAZER PHILADELPHIA, PA. (Term expires February, 1909 ) J. PARKE CHANNING NEW YORK, N. Y. FREDERICK W. DENTON PAINESDALE, MICH. JOHN B. FARISH New York, N. Y. (Term expires February, 1910)

Jan 1, 1910

Our merchant marine is rapidly outgrowing our consular service, according to Edward N. Hurley, Chairman of the United States Shipping Board, who urges that steps be taken immediately to provide facilities abroad for handling the millions of tons of shipping which will be afloat under the American flag in peaceful trade when the war is over. When peace is restored and our present tonnage is scattered over world trade routes, the consular service will be inadequate to handle our ships: Besides, it will have to work against the handicaps of obsolete shipping regulations and, in many cases, lack of experience. There are nearly 100 pages in the United States consular regulations dealing with shipping platters. . Many of these regulations are based on old treaties and many of them are obsolete. There are also differences between treaties with various countries. Our consuls often lack authority to handle matters involving the interests of our sailors and shipowners. Before we can operate a modern merchant marine we must revise, standardize, and simplify this whole mass of regulations and bring them up to the efficiency of other nations' practice.

Jan 12, 1918

By Paul Hett

The much-heralded Deep Ruth operation of Kennecott Copper Corp., at Ruth, Nev., is scheduled to become a producer by 1957. Inaugurated as a project in 1951, production was originally scheduled to start in 1953, but excessive water hindered shaft sinking. A revised schedule called for output by 1955, but again plans had to be changed. This time the change was to permit mining of an orebody that would have otherwise been lost because of block caving methods planned for the main deposit. The new ore is within the cave limits of the larger orebody, above the first production level. Ore will start coming from this new source in 1956, a year ahead of the principal operation. (See NEWS, page 344.) There is little doubt that current economic conditions and unforeseen expenditures for early shaft development will make the Deep Ruth a high-cost producer. Yet, some of the drawbacks of the Kennecott operation may be mitigated by the possibility that additional exploration will increase the already assured 25 million tons of 0.83 pet copper ore. While Kennecott is missing out on the current high copper market and is thus left with a potentially narrowed profit, the predicted demand for copper has created an optimistic feeling. Its development is certain to enlarge known U. S. copper reserves and significantly extend the life of Kennecott's Nevada operations.

Jan 4, 1955