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By L. Dudley Stamp

The years 1935 and 1936 have been momentous ones in the history of oil exploitation in Burma. While the possibilities of the discovery of an important new field in the country have become increasingly remote, there have been surprising and to some extent unexpected developments in and near the old established fields. Further, these developments have not only an important bearing on the future of the industry in Burma, but they point to conclusions of, world-wide significance in connection with the disposition of oil pools. BC'rma Independent of India According to the Government of India Act, passed by the British Parliament in 1935, Burma becomes independent of India, of which it was formerly a province. In future, therefore, statistics for Burma will be quoted separately from those of India. In 1934, 1935 and 1936 the oil production in India (including Burma) reached new high levels— though only a few per cent above the totals for 1919, 1920 or 1930. Part of the increase came from Assam, so that Burma's total is apparently below that of 1921. It must always be remembered, however, that Burma's largest potential producer—Singu—is used essentially by the Burmah Oil Co. as a reserve and its production is varied from year to year, and indeed from week to week, according to local market demand or the requirements of the Rangoon refinery. The figures of Table 1 must therefore be viewed in the light of these remarks.

Jan 1, 1937

By Richard M. Foose

WOULD you like to find a large new ore deposit next year? The answer is as obvious as the question is foolish. But perhaps the question does have some merit if we alter it slightly and ask: What are you doing about finding new ore? This one is more difficult to answer. Possibly you are doing nothing about finding new ore because you have proved reserves for many future years of production. Others may be investing some small percentage of time, effort, and money in mineral exploration, and reserves may be currently adequate, or inadequate, in terms of many future productive years. Still others may be engaged in large-scale mineral exploration programs involving large expenditures of time, personnel effort, and money. In whatever category you may be, a final question might well be asked. Is your current mineral exploration program, or lack of program, consistent with the long-range needs and objectives of your organization and of the mining industry as a whole, and is it designed to stimulate the growth of the industry in future years, or is it only a short-range program in response to some current situation?

Jan 3, 1958

By Heinrich Ries

The manufacture of fire-brick represents one of the oldest branches of the clay-working industry in New Jersey, and is of more importance than is commonly imagined. The New Jersey clays were first used for fire-brick after the war of 1812, and one of the earliest records, according to Professor Cook, shows that clay was taken from Woodbridge to Boston in 1816, arid used for that purpose. The value of the clays of the Woodbridge district does not seem to have been well and widely recognized for some years, however, although in 1855 the statistics, given in the Geological Report, show that clay for making 50,000,000 fire-bricks was then taken annually from the pits at Woodbridge, Perth Amboy and South Amboy. Perhaps the oldest works in the State was that known as the Salamander works (no longer in existence), where brick were made as early as 1825. A little later, in 1836, John R. Watson established a factory at Perth Amboy, and in 1858 Sayre & Fisher began the manufacture of fire-brick at Washington. The works of W. H. Berry at Woodbridge began operations in 1845, and have continued up to the present clay, although in 1896 the name was changed to J. E. Berry. The works of Henry Maurer & Son were established in 1856, and those of M. D. Valentine & Brother in 1865. These latter were started for making bath brick; later, sewer-pipe, and, finally, fire-brick and other refractory shapes were produced. A branch-works, located at Valentine on the Central railroad of New Jersey, was started in 1887. Even in the last two years several works have begun the manufacture of fire-brick. These include factories erected by

Jan 1, 1904

By Frank Hall

THE needs of the World War showed the necessity of a metal stronger than cast iron which would supplement the supply of steel. So patriotic metallurgists were spurred to new efforts to improve the status of that half-breed of the metal world that had been, more or less erroneously, christened semisteel. As a result, it was developed that for certain purposes semisteel was superior to steel in the manufacture of shells. Steel, because of its greater strength and toughness, is able to carry a greater charge of explosive, weight for weight; consequently, a steel shell can be expected to cause greater destruction when used against fortifications or other inanimate objects, while semisteel, because of its comparative brittleness and its resulting greater fragmentation, is capable of inflicting more serious loss of life when used against opposing forces of men. Therefore, each has its proper place in the economy of war. For the present purpose, steel may be defined as a comparatively pure iron whose physical nature is modified by small amounts of carbon, silicon, sulfur, phosphorus, manganese, and possibly other rarer elements; while cast iron generally is limited to approximately 93 per cent. of iron, the remainder consisting of larger percentages of carbon, silicon, sulfur, phosphorus, and manganese. Semisteel may be defined as cast iron in which the carbon and silicon have been reduced to as low a point as is consistent with maintaining the nature of gray iron, and in which the remaining elements are manipulated so as to give the greatest strength.

Jan 1, 1920

By C. M. Young

BITUMINOUS coal piled in heaps or bins frequently undergoes a process of spontaneous heating as the result of the absorption of oxygen. It seems probable that the first absorption of oxygen by coal which has not previously been exposed to the air may occur as a condensation or a combination of oxygen in some form which does not result in the production of carbon dioxide, but slow combustion soon begins. The absorption of oxygen is accompanied by an increase of temperature, and this by in increased rapidity of absorption; hence the dangerous condition proceeds from bad to worse, until the kindling point is reached, unless the process is interrupted. A dangerous rise of temperature can be prevented by excluding oxygen, by increasing the bulk of coal in proportion to its surface exposed, or by circulating enough air to dissipate the heat produced. The storage of coal, in practice, varies from almost complete exclusion of oxygen, by storing under water, to such freedom of access as exists when the coal is stored in open piles. Oxygen available for absorption by coal is supplied by the air in the interstices between lumps and by additional air which may enter the pile through circulation. The size, of the coal largely affects both of these supplies; for if the fragments a re small the spaces between them constitute a small percentage of the total volume, and little oxygen will be available unless the circulation of air brings in a fresh supply, while with large fragments the percentage is relatively large; circulation also is much easier through a pile of coarse lumps. In the case f lump coal, although a large amount of air may be present, the exposed surface is comparatively small and there is little opportunity for the absorption of oxygen to so rapid as to cause dangerous heating. Attempts have been made to prevent heating by allowing a sufficient circulation of air to carry off the heat generated; obviously this method cannot be applied to fine sizes nor mixed sizes.

Jan 2, 1918

The Library of the above-named Societies is open from 9 A.M. to 9 P.M. on all week-clays, except holidays, from September 1 to June 30, and from 9 A.M. to 6 P.M. during July and August. The Library contains about 55,000 volumes, including sets of technical periodicals and the publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library can render valuable service through correspondence; letters requesting information will receive special attention. The Library is prepared to furnish references and copies of articles on mining and metallurgical subjects; to determine the existence of mining-maps, and to furnish general information as to the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. The members of the Institute can be of service to the Library by forwarding copies of mining-reports, maps privately issued, and similar material, which will be classified, indexed, and made available to other members. Suggestions for additions to the Library, either by purchase or personal solicitation as gifts, will be welcomed. It is hoped that members while in the city will use the Library freely, and assurance is, given that most careful service will be rendered to them.

Jan 9, 1913

By J. J. Rutledge

THE United States Bureau of Mines established at Bruceton, Pa., in 1909, an experimental mine, for the purpose of testing the means of preventing and limiting mine explosions. During the last ten years numerous explosions have been caused to originate in .this mine for investigative purposes and the rate of propagation of the explosion wave, the pressure developed per unit of area by the explosions, and, the general results of the explosions have been carefully recorded and. studied. Means of preventing mine explosions or of limiting them to the areas in which they originate have been developed. A great deal of valuable information has been derived from the work in this mine and much more useful and valuable information will be obtained in. the future. The writer would plead, not for the opening of experimental mines in all the important coal-producing fields in the United States, but for the opening of demonstration mines, or mines in which experiments could be made with the various details of coal mining. The United States Department of Agriculture has established, in nearly every state, stations that undertake experimental work for the benefit of the agricultural interests. In addition, small demonstration plats are set aside, in suitable locations in the farming districts, where various crops are grown under scientific direction, so that the farmers in the neighborhood can note the results obtained and profit thereby. Something like this should be done for the coal-mining industry. If experimental or demonstration mines were established, methods of working adapted to local conditions could be worked out. Owing to competition in the same markets, small capitalization, or low profits, it may be an utter impossibility for any one company to try a new method of mining. Labor conditions may prevent the trial of a new method of working. It may be impossible or inadvisable to disturb existing working conditions for fear of causing trouble among the miners through real or fancied changes in the scale of wages.

Jan 2, 1920

Jan 1, 1966

By V. R. Garfias

A survey of the resources of mineral fuels, coal, petroleum and natural gas presupposes a clear distinction between the known amount underground and the "proven reserves"; the'portion that can be economically brought to the surface and made available for utilization. Only a fraction of the coal and petroleum in producing fields is or can be economically brought to the surface and not all of this is economically utilized; also, although practically all the natural gas can be economically recovered and utilized, in actual practice a large part of the total volume that reaches the mouth of the wells is wantonly blown into the air and wasted. It is thus estimated that of the total amount of coal underground about 40 per cent remains unrecovered, or is otherwise wasted, before it reaches the consumer; that only some 25 per cent of the petroleum in proven fields is actually brought to the surface; and that even if practically the entire volume of natural gas can be economically utilized, in actual practice close to 25 per cent of the total produced is now absolutely wasted. And the dissipation of this gas, unwarranted as it is, not only diminishes the gas supply but diminishes also the proven reserves of petroleum from such fields as the Panhandle of Texas, where petroleum and natural gas are produced simultaneously. Many factors affect the estimates of the proven reserves of mineral fuels, such as the capacity and nature of the reservoir, its depth, the quality of the product, the efficiency of recovery, the price of the fuel and its byproducts, etc., etc., but superseding at times all of these in connection with petroleum and natural gas deposits is the effect of "subsoil ownership" on the rate and methods of exploitation of the deposits. As a result it should be a comparatively simple matter to eliminate waste and overproduction, and thereby increase the proven reserves of petroleum and natural gas, in Russia, Iran and Iraq, where the subsoil rights are nationalized, or in any country in which there is or can be quickly established an effective legal control of the underground deposits and the manner of their exploitation. It has been and it is now, on the other hand, almost an impossible undertaking to intelligently regulate the petroleum and natural gas production in the United

Jan 1, 1935

By William M. Agar

Now that both the national and state legislatures are seeking ways of reducing expenses, the appropriations for geological investigation and for the study of mineral resources have been greatly reduced and in some cases entirely stopped. Is this policy justified? The sums saved by these reductions are always small. If the work accomplished by these surveys has no intrinsic value to the community, but is only an interesting way of spending some of the people's money when that money is plentiful, there should be no surveys at any time. If, on the other hand, they perform a necessary function, it is indeed foolish and short-sighted to save these paltry sums to the detriment of the community. It is not my purpose to undertake a general justification of geological surveys. Rather, 1 wish to call attention to the work of one state survey that has been discontinued, and to indicate ways in which the work was valuable to the people, even though that state's mineral resources are not very important, and why it should be continued. Though at one time in Connecticut's history iron mining and smelting were important, and copper was mined in appreciable quantities in two localities, it is many years since it could be regarded as a mining state. At present Connecticut stands far down among the states in the value of its mineral products. Granite for architectural and structural purposes, trap rock, clay, agricultural lime, feldspar and quartz, together with a few other nonmetallic minerals, are produced in appreciable quantities, but the natural resources of the state consist at present much more largely in its attractive scenery, woods, lakes, shore line, and in the opportunities that these offer for rest and recreation. Is the prosecution of geological work in such a state a waste of the taxpayer's money? Or can it be that though it was formerly valuable, the work is now completed? The only way to answer these questions is to review the geological work done in the past and to consider the type of information the people want, as reflected in the requests that have been received by the director of the survey in the last few years. There have been two periods during which Connecticut has supported geological work within its borders. The first began in 1835 when Percival

Jan 1, 1935

By William M. Agar

Now that both the national and state legislatures are seeking ways of reducing expenses, the appropriations for geological investigation and for the study of mineral resources have been greatly reduced and in some cases entirely stopped. Is this policy justified? The sums saved by these reductions are always small. If the work accomplished by these surveys has no intrinsic value to the community, but is only an interesting way of spending some of the people's money when that money is plentiful, there should be no surveys at any time. If, on the other hand, they perform a necessary function, it is indeed foolish and short-sighted to save these paltry sums to the detriment of the community. It is not my purpose to undertake a general justification of geological surveys. Rather, 1 wish to call attention to the work of one state survey that has been discontinued, and to indicate ways in which the work was valuable to the people, even though that state's mineral resources are not very important, and why it should be continued. Though at one time in Connecticut's history iron mining and smelting were important, and copper was mined in appreciable quantities in two localities, it is many years since it could be regarded as a mining state. At present Connecticut stands far down among the states in the value of its mineral products. Granite for architectural and structural purposes, trap rock, clay, agricultural lime, feldspar and quartz, together with a few other nonmetallic minerals, are produced in appreciable quantities, but the natural resources of the state consist at present much more largely in its attractive scenery, woods, lakes, shore line, and in the opportunities that these offer for rest and recreation. Is the prosecution of geological work in such a state a waste of the taxpayer's money? Or can it be that though it was formerly valuable, the work is now completed? The only way to answer these questions is to review the geological work done in the past and to consider the type of information the people want, as reflected in the requests that have been received by the director of the survey in the last few years. There have been two periods during which Connecticut has supported geological work within its borders. The first began in 1835 when Percival

Jan 1, 1935

By Emanuel Trotz

As the long-felt need of a reliable and easily-managed pyrometer has now been fully supplied, by the latest form of Professor Wiborgh's pyrometer, an account of this instrument will, per-

Jan 1, 1893

Jan 1, 1930

By R. M. Stewart

INTRODUCTION Requirements for achieving economic slope stability in open pit mining must not only be met during the operating stages but in all preceding stages of mine development. In many operating mines little or no emphasis was ever placed on evaluating the stability of possible slopes during the exploration and planning stages. The purpose of this discussion is to emphasize the necessary considerations that should be made in all stages of development in order to achieve the safest and most economic pit slopes. The most economic slopes may not always be the safest slopes and it is incumbent upon the mine operators and engineers to achieve an optimal combination of economics and safety. The stability requirements outlined are based on the profit motive and are, therefore, practically oriented. Long-term basic research or theoretical studies are considered important only to the extent that they can be shown to have a definite payoff. Consideration will first be given to the information required for stability analysis, which can be determined during the exploration and evaluation stage, followed by further stability work necessary during the mine planning and layout stage. Particular emphasis is then placed on the operating stage in which blasting, dewatering, artificial stabilization, and slope failure are discussed. Lastly, the importance of a logical and orderly research procedure is stressed. EXPLORATION AND EVALUATION STAGE The purpose of the exploration and evaluation stage in the mining scheme is to find and delineate a potential orebody. Discovery and delineation commonly involve drilling tens and in many cases hundreds of boreholes. These boreholes, which may cost as much as $20.00 per foot of depth for a cored hole, are usually abandoned once drilling is completed. Stability evaluation for a potential open pit should begin at this stage by taking advantage of the existing boreholes. Rock and soil properties, as well as hydrologic parameters, may be obtained from both the borehole and the core. Seismic velocity and neutron probes may be used to log the borehole to obtain elastic moduli data. A borehole dilation jack may also be used to give backup information on the rock and soil elastic parameters. Use of a core orientation system can result in the determination of fault and joint frequency and distribution. Before splitting or otherwise disturbing the fresh core, qualitative evaluation

Jan 1, 1972

By William Hilliard

IN any manufacturing business, it is of vital importance that the management should know the exact cost of the units of production. Without such knowledge, a company can sell blindly in the open market, obtaining the best prices it can in competition with other firms, and manage perhaps to continue in business for a time; but at any moment, and especially in a period of falling prices, such a firm is at a loss to know exactly at what point it can sell at a profit and exactly how much it is losing per unit if it sells below that point. Furthermore, it is necessary not simply to know the exact total cost per unit, but to know definitely all the different-factors which enter into that cost. A firm manufacturing pocket knives had been doing a profitable business for many years when it began to earn smaller and smaller profits, until there was scarcely any profit at all being realized. Being unable to determine exactly what its future policy should be, it called in experts who studied the past records carefully and followed out for a period a better cost, system. Investigation then showed that on several different kinds of knives in common use, a small profit per unit was being made. On a number of special kinds of knives, of which the firm was very proud, it had been forced to cut prices under the pressure of outside competition and had believed that a small profit per unit was still being made on that product, while a detailed cost analysis showed that a loss was being incurred on each knife of that kind produced. It then became clear that the company must either give up the special line and concentrate wholly on the cheaper knives and extend their sales to territory not yet developed; or expand its plant and produce more of the higher grade knives and thus lower the cost per unit enough to make money on the higher grade knives also, if conditions warranted such expansion. Investigation revealed that the market for large quantities of the high-grade -knives was decidedly uncertain and that the most promising move would be to manufacture only the less expensive knives on a larger scale. That plan was carried out and the concern began again to make a better profit.

Jan 1, 1932

By F. C. von der Weid

The mining district of Sao Fidelis, in the northern part of the State of Rio de Janeiro, is situated on the Paraiba River, where it crosses the Serra do Mar (Mountain of the Sea), in the center of a mountainous country having numerous graphitic outcrops. For a long time, these outcrops were irregularly explored by local people, who had little means and no technical advice. A few years ago, the Cia. Brasileira de Minerasgo de Grafite took over the control of some of the more important outcrops and entrusted to me the task of studying the ores and establishing a flowsheet for a pilot plant to be situated in São Fidelis—the ore to be concentrated being mostly of a very high grade. Mineralization and Ores The rocks of the district are mostly gneiss and crystalline schists, with occasional interstratification of dolomitic limestone belonging to the Archean Brazilian Fundamental Complex. The general direction of the beds is roughly between 60" and 80°E., with variable dip, generally nearly vertical. Mostly, direction and dip of the graphitic outcrops is concordant with the embanking gneisses or schists. These outcrops seem to be aligned in two or three parallel zones (Pádua, São Fidelis, Mac- abu), the Sao Fidelis zone being the best known and the most important to date. Two outcrops of the São Fidelis zone, Saudade and Sao Benedito, are now being exploited. Mining has been carried out, so far, on a small scale. The mineralization consists of a vein of nearly massive graphite in a very compact, partially granitized gneiss, with vertical dip. The vein is most irregular, with nests and lenses irregularly distributed along the fracture plane. The ore consists chiefly (particularly in Sao Benedito) of massive graphite appearing and disappearing along the main direction of the vein, forming a succession of irregular lenses in a sort of rosary design. The average width is more or less one foot, with variations from zero to 6 feet. The lode minerals are quartz, a little feldspar and garnet (the latter having its origin perhaps in the embedding gneisses), with rare ferruginous clays on the outcrops. In Saudade a little pyrite, pyrrhotite and chalcopyrite is found occasionally, as well as a carbonaceous mineral, very light, black and shiny, with conchoidal fracture, looking like a sort of jet. The composition of this mineral has not yet been established, but it seems to be very complex. The mineralization seems to be hydro-thermal at a rather low temperature, perhaps mesothermal. The paragenesis, according to samples from Saudade, seems to be as follows, the earlier minerals being listed first: pyrrhotite, pyrite, chalcopyrite, with quartz concomitant to the three and graphite formed later. Age of the mineralization is still uncertain, owing to the very in-

Jan 1, 1948

By F. C. von der Weid

The mining district of Sao Fidelis, in the northern part of the State of Rio de Janeiro, is situated on the Paraiba River, where it crosses the Serra do Mar (Mountain of the Sea), in the center of a mountainous country having numerous graphitic outcrops. For a long time, these outcrops were irregularly explored by local people, who had little means and no technical advice. A few years ago, the Cia. Brasileira de Minerasgo de Grafite took over the control of some of the more important outcrops and entrusted to me the task of studying the ores and establishing a flowsheet for a pilot plant to be situated in São Fidelis—the ore to be concentrated being mostly of a very high grade. Mineralization and Ores The rocks of the district are mostly gneiss and crystalline schists, with occasional interstratification of dolomitic limestone belonging to the Archean Brazilian Fundamental Complex. The general direction of the beds is roughly between 60" and 80°E., with variable dip, generally nearly vertical. Mostly, direction and dip of the graphitic outcrops is concordant with the embanking gneisses or schists. These outcrops seem to be aligned in two or three parallel zones (Pádua, São Fidelis, Mac- abu), the Sao Fidelis zone being the best known and the most important to date. Two outcrops of the São Fidelis zone, Saudade and Sao Benedito, are now being exploited. Mining has been carried out, so far, on a small scale. The mineralization consists of a vein of nearly massive graphite in a very compact, partially granitized gneiss, with vertical dip. The vein is most irregular, with nests and lenses irregularly distributed along the fracture plane. The ore consists chiefly (particularly in Sao Benedito) of massive graphite appearing and disappearing along the main direction of the vein, forming a succession of irregular lenses in a sort of rosary design. The average width is more or less one foot, with variations from zero to 6 feet. The lode minerals are quartz, a little feldspar and garnet (the latter having its origin perhaps in the embedding gneisses), with rare ferruginous clays on the outcrops. In Saudade a little pyrite, pyrrhotite and chalcopyrite is found occasionally, as well as a carbonaceous mineral, very light, black and shiny, with conchoidal fracture, looking like a sort of jet. The composition of this mineral has not yet been established, but it seems to be very complex. The mineralization seems to be hydro-thermal at a rather low temperature, perhaps mesothermal. The paragenesis, according to samples from Saudade, seems to be as follows, the earlier minerals being listed first: pyrrhotite, pyrite, chalcopyrite, with quartz concomitant to the three and graphite formed later. Age of the mineralization is still uncertain, owing to the very in-

Jan 1, 1948

By E. William Heinrich

With the mounting emphasis on unconventional energy sources, total consumption of lithium minerals will increase significantly in the next decade. The recent development of the lithium battery, for example, may greatly boost the demand for lithium metal. At the same time, the growth in the ceramic, glass, and chemical industries is bound to increase the demand for lithium minerals. In fact, the entire consumption or utilization breakdown of lithium minerals will change considerably from its current pattern. Briefly, today's market for lithium minerals' can be grouped into three categories: (1) Lithium concentrates. Accounting for 57% of market use, these concentrates are beneficiated Li-A1 silicates for ceramic, glass, and glass-ceramic raw materials. The concentrates are chiefly spodumene; inverted iron-depleted beta-spodumene; and petalite or its isochemical decomposition product spodumene + quartz intergrowth ("squi"). In the past, lepidolite has also been used.

Jan 9, 1974

By John L. Schroder, Woods G. Talman

EXPERIENCE has shown that certain known natural conditions and other indefinite characteristics combine to make a mining area vulnerable to mountain bumps. Some of the known conditions are heavy overburden, an overlying stratum of strong non-elastic rock, a structurally strong coal seam that does not crush easily and yet is the weakest stratum in the series, and a floor stratum of more than ordinary firmness. The indefinite characteristics could include resistance of top or bottom of a coal seam to lateral flow, effect of immediate top and bottom strata, nature of the coal seam, and other factors about which very little is known. It is in this area that exhaustive study is needed to achieve positive control of the dreaded mountain bump hazard.

Jan 8, 1958

By Granville S. Borden

MANY complaints have been filed by mine prospectors, explorers and producers about inequities in mining taxation. They have insisted upon improvement, and in the past 35 years there has been some progress. Many of the best taxation provisions made to date are those contained in the Revenue Act of 1951. Mining economics presents special problems, a fact even recognized by many textbooks. Certain provisions have been made to take care of mining taxation rights, but these have been made by Congressional act and do not represent basic, constitutional, guarantees. Despite special provision, in the form of depletion allowances, there remain injustices. The industry faces the problem of gaining adequate income tax allowances for exploration and development expenditures, operating losses, and bonus and subsidy payments. Problems in mine taxation arose soon after the adoption of the 16th Amendment. This amendment gave Congress the power to impose income taxes. Supreme Court decisions against a number of mining companies held that Congress, under its power to tax income, could tax net operating revenue before depletion allowance was deducted. The court also ruled that the right to deduct depletion is a matter of Congressional permission. There is no statute provision permitting mining stockholders to recover their investment out of dividends while the mine is being operated. The Supreme Court did not recognize that part of mining proceeds are actually amortization of the cost of mineral rights. Both these omissions stem from failure to recognize that by its very nature mining consumes its mineral rights and therefore that a part of gross proceeds are not income but recovery of capital. Suppose a Congress unfriendly to mining interests repeals the provisions that allow deductions for depletion. Under such a situation assume that a corporation buys a mineral deposit for $300,000. They mine the deposit and earn an operating profit of $500,000. At the current rates they would pay a Federal Income tax of in excess of $250,000. This venture results in a loss of $50,000 as shown in the table below. For the example given the absence of depletion provisions in income tax law would turn ore into waste rock, because the word "ore" connotes commercially mineable rock. [ ] In retrospect the conclusion is clear: If the Supreme Court had recognized that a part of mining proceeds represent in reality sales proceeds of mineral rights, then profits derived from such sales would have been taxed at the favorable long-term capital rates, instead of being taxed at the high normal, surtax and excess profits rates. It is a question whether percentage depletion allowances offset this tax situation. History The history of depletion allowances has been one of general improvement. The original act did not include depletion, but an allowance at the rate of 5 pct of gross proceeds was provided in 1913. The Acts of 1916 and 1917 allowed depletion upon cost of property, and in 1918 the law was further changed to permit depletion upon cost, or market value as of date of discovery. In 1932 metal, coal and sulphur properties were permitted to elect depletion in percentages of gross income, limited to 50 pct of net income, in lieu of cost depletion. Shortly thereafter the rule was changed and percentage depletion is now allowable in any case where it is higher than cost depletion. Since 1942 percentage depletion allowances have been extended to cover many nonmetals, and in 1951 the rate for coal mines was increased from 5 to 10 pct of gross income. It is interesting to note that these allowances have been retained, and even

Jan 1, 1952