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By Noel Stearn

WHEN the Age of Machinery was suddenly thrust upon civilization about the beginning of the 19th century, an unprecedented demand for mineral resources sprang up. This demand brought about the rapid development of the known ore deposits and the discovery of such other deposits as could be encountered by energetic and canny prospectors. Thus in the countries now reasonably accessible nearly all orebodies have been located except those which are totally concealed even from the eyes and "senses" of experienced and expert prospectors. The high rate of exhaustion of known ore deposits and the necessity of looking farther and farther ahead for raw materials as a matter of insurance on the stupendous capital outlays involved in mining, development, and conversion operations, have resulted in exceptional activity in three different fields of effort. The first is purely geographic. Prospectors are now penetrating the few hitherto inaccessible regions in the hope of stumbling upon exposed ore deposits or locating visible indications of their presence. The second is chemical. Industrial chemists and metallurgists are seeking to facilitate the exploitation of lower grade ores or to find methods of recovering valuable metals from common substances. In the third field of effort lie the activities of the economic geologist and the mining engineer, who endeavor to locate concealed ore deposits which would remain hidden from the prospector no matter how expert or conscientious he might be. Obviously the task which such a man must face is both exacting and indefinite, and the tools which he has heretofore been permitted to bring to it are, for the most part, abstract-a knowledge of certain fundamental principles and processes involved in the origin, occurrence, structure, and distribution of deposits of natural resources and of the rocks which form the environments of those deposits; and a process. of reasoning by analogy supplemented by the use of the diamond drill, or such artificial exposure as -the test pit, trench, shaft, or tunnel.

Jan 1, 1928

By Eugene Guccione

For at least 10 years, various industry people had warned about the alarming decline in the nation's oil and gas reserves. Then, in October 1973, the Organization of Petroleum Exporting Countries launched an oil embargo and sharply increased crude oil prices. Suddenly, everybody discovered the "energy crisis." In November 1973, former President Nixon advocated a Project Independence program so that ". . . by 1980 we shall be able to meet America's energy needs from America's own energy resources."

Jan 5, 1975

By John W. Trammell, Chester O. Ensign

Efficient mining of copper ore at the White Pine mine in Michigan's Upper Peninsula is partially dependent on the rather unique problem of predicting variations and rock types in a barren stratum called the upper sandstone. The pronounced effect which this formation has on the local mining techniques is reflected by the necessity of deciding whether to mine the sandstone along with ore-bearing rock, thus diluting overall ore grade, or, alternatively, leaving the sandstone behind to form the mine roof. THE OREBODY AND MINING TYPES In the mine, the cupriferous zone of the Nonesuch shale is divided into three major portions (Fig. I). Lying conformably on top of the Copper Harbor formation (or "lower sandstone") is the lower part of the orebody, the parting shale. The parting shale is overlain by the upper sandstone. On top of the upper sandstone, the basal portion (8 ft) of the upper shale is quite similar to the parting shale. Both the upper shale and parting shale are divided into a number of smaller stratigraphic units, each having a characteristic copper content, as shown by the histogram of Fig. 1. Other authors have dealt in detail with the stratigraphy and mineralogy of the orebody, so it will suffice here to call attention to the low copper content of the upper sandstone.

Jan 12, 1964

By Paul R. Wieber, Atam P. Sikri

This paper describes the U. S. Energy Research and Development Administration's (ERDA) program to develop in situ coal conversion processes, especially gasification. The potential of this technology, the technical directions being explored, and the program strategy to carry the process concepts toward commercialization are emphasized. The geographic location of the U. S. coal resources and a market analysis are described. Commercially successful in situ coal processes could add over a trillion tons of coal to the U. S. coal reserves. The economics of these processes is compared with surface gasification. Independent studies show this process to be 25% cheaper than surface gasification for Western coals. The major projects are briefly described. The Linked Vertical Well process is in the most advanced stage and shows great promise. The last test produced a low-Btu gas averaging 171 Btu per standard cubic foot for average production rates of 8.5 million standard cubic feet per day. The other projects are Packed Bed, Longwall Generator, and Steeply Dipping Beds. Unique factors of the process development are discussed which may lead to commercial processes in the near term. A development strategy is proposed by which this technology could be commercialized before 1985 with potentially lower gas prices and lower environmental impacts, relative to mining plus surface gasification.

Jan 5, 1978

By Russell Spry, Paul Schutz

The property of Pioneer Gold Mines of B.C. Limited is in the Lillooet mining district of British Columbia. It is on Cadwalleder Creek, 54 miles distant by motor road from Shalalth, a station on the Pacific Great Eastern Railway. Interests identified with the present company installed a small amalgamation plant on the property in 1924, consisting of a jaw crusher, Bryan mill and amalgamation plates, in which 75 per cent extraction was made on mill feed averaging 1.0 oz. gold per ton, the tailing being stacked for future treatment. That plant was operated until 1928, when the present company was formed and a 100-ton continuous counter current decantation cyanide plant was built. A second unit, having a nominal capacity of 200 tons daily, was added in 1932 and put into operation during September of that year. When handling ore comparatively free from slow-settling material, the combined capacity of the two units is 400 tons, the original plant now handling about 140 tons maximum. Production to date, from Pioneer, has been about $6,500,000, the present monthly production being better than $250,000 from about 370 tons ore daily, the recovery being 97 per cent. During the fiscal year ending March 31, 1934, a total of 112,936 tons ore and old amalgamation tailing was milled, the mill feed averaging 0.7670 oz. gold and the recovery amounting to 0.7422 oz. gold per ton, or 96.77 per cent. Milling costs, including refining and mint charges, during this period, amounted to $1.45 per ton of ore. Since the building of the first unit of the cyanide plant in 1928, direct cyanidation has been employed, no attempt being made to remove coarse gold from the circuit, other than that cleaned up from the grinding mills during relining and from the classifiers, as occasions permit. In the hope of still further increasing recovery, researches are going forward at this time with the view to removing some of the sulfides after primary grinding, the expectation being that selective treatment of this more refractory portion of the ore may hold economic possibilities.

Jan 1, 1935

By J. P. Lesley

The Pittsburgh coal-region, if we regard the greatness of its extent, the picturesque beauty of its scenery, the salubrity of its climate, its relative situation on the Continent, the fertility of its soil, its unrivalled mineral wealth, and its magnificent system of natural transportation, is, perhaps, the most valuable spot on the surface of the planet. Unlike the mythical Paradise inhabited by one man and one woman, it swarms with an abounding population, not living on the free gifts of nature without care and without toil, hut expending its energies in unremitting labor, reinforced by the most elaborate machinery, in the production of everything which mankinds needs or desires; and unlilte the Paradise of story from which flowed the four great rivers of the world in opposite directions, its own four rivers How from the surrounding world into it, to constitute by their union the great highway water-course which divides the Northern from the Southern States. These rivers are the Monongahela, coming from the south, the Yonghiogheny from the southeast, the Kiskiminetas from the east, and the Allegheny from the north. Uniting at the great city of pittsburgh, they constitnte the Ohio, which flows northwest and west, and then south and southwest, toward the Mississippi. The Monongahela has been made navigable by a system of dams and pools the Allegheny was navigable in its natural condition; the KisKiminetas was made navigable by a State canal which has been vacated ; and the Youghiogheny remains unnavigable. Railroads supplement the deficiencies of the rivers, follow their hanks, and share in the transportation for which the waters are not sufficient. Railroads and rivers concentrate at Pittsburgh; other railroads cross the highlands to the east and west; and branch roads ascend the side-valleys and ravines to the mines on the uplands. The whole region is a scene of life; towns and villages dot its surface in all directions ; hundreds of gangways open upon the sides of all the valleys, and deliver coal to trains of cars which move beneath them at water-level; furnaces and rolling-mills abound; hundreds of oil-wells furnish a flood of liquid fuel to pipe-lines

Jan 1, 1886

By Frederick N. Clark

These tests were made under the writer's supervision in the mining and metallurgical laboratories of the Massachusetts Institute of Technology, in the winter of 1888-89, by Mr. Robert C. Williams, of Marquette, Mich., assisted by Mr. J. B. Seager, of the

Jan 1, 1890

[TRANSACTIONS Indexes to Vols. 1-35, 36-55, 56-72, 73-117 (set of 4 Indexes). DIVISIONAL TRABSACTIONS AND SPECIAL EDITIONS Coal Division Volume, 1930, 1931, 1932, 1934, 1936, 1938, 1940, 1942, 1944. Institute of Metals Division Volume, one each year 1927-1945.]

Jan 1, 1946

By Mahesh C. Jha

Arsenical gold ores occur in many parts of the world, including numerous mines in Canada and the western United States. Free gold is often finely disseminated in the grains of sulfide minerals, arsenopyrite, pyrite, orpiment and realgar. Generally a sulfide concentrate is produced by flotation. Arsenical ores or concentrates are not amenable to direct cyanidation and therefore are considered refractory. A wide variety of roasting equipment and conditions have been used by the mills to remove arsenic and sulfur from these concentrates. The resulting calcine is easy to cyanide and gold is recovered from the cyanide solution by zinc dust cementation. Room-temperature potential-pH diagrams and high-temperature phasestability diagrams are presented to discuss the chemistry of the gold cyanidation, cementation, and roasting steps in the presence of arsenic. The environmental aspects of arsenic discharge are also included.

Jan 1, 1984

By P. V. Faragher

A metal or alloy finds its place in commerce in proportion to its ability to serve certain purposes better and more economically than other materials. While there is some overlapping of the fields of application of the various metals under discussion in this symposium, each one has its uses for which it is especially adapted. While aluminum is the most recent of the metals to enter the field, the development of the industry has been based on its peculiar properties, by virtue of which new uses for non-ferrous metals have been created. There has been substitution of this new metal for other members of the group but there has been a far greater development in entirely new fields. In common with the other non-ferrous metals, aluminum is resistant to atmospheric corrosion. It also withstands the action of many of the common chemical reagents, strongly alkaline substances being the notable exceptions. The outstanding properties on which the application of aluminum is based are its low specific gravity and its ease of fabrication into the forms in which it is used. It is noteworthy that this property of specific lightness is retained in all the commercial aluminum-base alloys. This statement does not apply to aluminum bronze; this is more properly a copper-base alloy, since aluminum enters into its composition to the extent of only about 10 per cent. None of the commercial casting alloys of aluminum has a density exceeding that of the parent metal by more than about 10 per cent., and some are actually lighter. In the so-called "strong alloys" of aluminum in which strengths comparable to that of mild steel are developed by heat treatment, the greatest increase in density is only slightly more than 3 per cent., and one of these, also, is lighter than aluminum. This property of lightness combined with the desirable mechanical properties of the alloys, makes aluminum especially suited for parts of moving assemblies where saving in power, as well as a decrease in stresses resulting from inertia and vibration, are of importance.

H. H. Kellogg (Columbia University)—The accurate measurements of the equilibrium gas ratios for the reaction: Pb(1) + H2S = PbS(c) + H2 [I] reported in this paper are a distinct contribution to the literature, and the authors are to be congratulated. I wish to comment, however, on the correlation of the data which is presented. The authors show a straight line correlation of log H2S/H2 vs 1/T, Fig. 1, and are satisfied with this for calculation of ?Fo even when extrapolated to low temperature (427 °C). Heat capacity data for the constituents of this reaction are available (at least to 900°K), however, and ACP for reaction [I] is finite and positive in the temperature range studied. Simplification of the heat capacity equations yields: ?CP= 2.71 + 1.65 x 10-3T (298°-900°K) This positive value of ?CP should result in a small but noticeable curvature of a plot of log K vs 1/T. That the experimental data fail to show such a curvature may be traced to another oversimplification of the author's treatment of their data. They assume that the activity of liquid lead is unity for all temperatures, so that

Jan 1, 1961

By W. H. Bassett

THE modern smelting and refining of copper is distinctly an American development. The present demand for sound and perfect castings for rolling is due to the development of American industry. Prac-tically every article made from sheet metal or, for that matter, from any form of metal is made by mass produc-tion methods. Faulty material disturbs the orderly sequence of operations and in addition requires expen-sive inspection and unbearable rejection of finished product. This demand, therefore, is positive and will have to be met. Some mines produce ore that can be smelted and re-fined without the electrolytic process into satisfactory copper for the wrought metal industry, and some of these ores carry small amounts of impurities that are of use in hardening and toughening the copper. Most of the copper ore mined contains impurities that must be removed and, fortunately, precious metals which are separated at the same time make this re-moval profitable. The modern electrolytic refineries have their methods so well under control that the product meets all re-quirements without question if properly fire refined and cast. The "if" in this case is important, because there is evidence of carelessness or want of control at times in the material from some of the producers. It is nec-essary that the melted cathodes should be saturated with oxide to dispose of sulfur and that the copper should then be poled to the proper pitch or set. Sometimes statements leak out to the effect that it is unnecessary to oxidize completely the molten cathodes and a little less rabbling saves poles, which are expensive. The re-sult is that the rolling mill gets porous castings and produces seamy or slivered sheets or strips. The condition of the molds, their temperature, and the temperature of the metal are all important to good copper cakes, wedges, or wire bars. Cracked, and burned molds leave rough places and porous spots. Molds which are out of shape, or cracked, make shrink-age cracks which gap open when the castings are hot-rolled. Dampness means porosity. Drops of oil mean porous or honey-combed areas. Poor or irregular dress-ing means mold wash in the castings. Cold copper or slow pouring means cold sets.

Jan 4, 1928

By Paul R. Wieber, Atam P. Sikri

This paper describes the U. S. Energy Research and Development Administration's (ERDA) program to develop in situ coal conversion processes, especially gasification. The potential of this technology, the technical directions being explored, and the program strategy to carry the process concepts toward commercialization are emphasized. The geographic location of the U. S. coal resources and a market analysis are described. Commercially successful in situ coal processes could add over a trillion tons of coal to the U. S. coal reserves. The economics of these processes is compared with surface gasification. Independent studies show this process to be 25% cheaper than surface gasification for Western coals. The major projects are briefly described. The Linked Vertical Well process is in the most advanced stage and shows great promise. The last test produced a low-Btu gas averaging 171 Btu per standard cubic foot for average production rates of 8.5 million standard cubic feet per day. The other projects are Packed Bed, Longwall Generator, and Steeply Dipping Beds. Unique factors of the process development are discussed which may lead to commercial processes in the near term. A development strategy is proposed by which this technology could be commercialized before 1983 with potentially lower gas prices and lower environmental impacts, relative to mining plus surface gasification.

Jan 1, 1979

By E. H. Greener, M. E. Fine

The internal friction (1/Q) of cobalt Fig. 1 (measured by an electrostatic dynamic method1) near 250°C begins to increase rapidly on heating and continues to increase until 560°C, the highest tem- perature measured. In the plot of log of 1/Q against 1/T, above 250°C the data nearly fit two straight lines intersecting at 400°C, approximately the temperature of the hexagonal-cubic transformation. The higher temperature branch corresponds to an effective activation energy of 6500 cal per mole, the lower temperature branch 11,000 cal per mole. Young's modulus Fig. 2 increases approximately

Jan 1, 1959

By Nicholas T. Camicia

A career in the coal mining industry today offers students one of the most interesting and challenging opportunities available in the industrialized world. As reserves of other fossil fuels dwindle in face of the world's demand for energy, it has become apparent that coal, once the king of energy sources, must be relied upon again as the major fuel for powering industrial growth in developed and developing nations. Centuries of coal supplies lie beneath the earth's surface, assuring the world of a steady, plentiful supply of energy until science and technology can produce a way to harness and efficiently use renewable sources, such as solar. The need to increase our use of coal during the last two decades of the 20th century is reason enough to believe that the future growth of the coal industry is assured. A major impediment to that growth might be backward national public policies that could restrict the full utilization of our coal reserves. These policies could result from overregulation and a failure of the public to recognize that coal use, with proper techno- logical safeguards, is compatible with our society's environmental-quality objectives. Communication of this problem and its solution is a major undertaking of the coal industry in the 1980s. At the end of the 1970s7 the American coal industry was producing approximately 635 Mt/a (700 million stpy) of coal. To meet the nation's projected energy needs by 1985, the annual tonnage must be doubled. A similar scenario is predicted for the rest of the world. Such growth in the modern international business world will require huge additional amounts of capital, equipment, and people who know how to wisely raise and apply the capital; use the equipment productively; and deal with the many community, public, and governmental problems such expansion will create. Whether a student's interest is in actual mining operations, business administration, engineering, finance, law, industrial relations, marketing

Jan 1, 1981

Raymond Weir Smyth, born Nov. 3, 1888, was the son of Herbert Weir Smyth, professor of Greek Literature at Harvard University. He graduated (A. B.) from Harvard in 1909 and later pursued advanced studies there in chemistry and in metallurgy. He held the position of metallurgist for the American Steel and Wire Co. at Worcester, Mass., and also for the Steel and Tube Co. at Youngstomn, Ohio. For a time he was inspector of munitions for the British Government and stationed at the Railway Steel and Spring Co. at Latrobe, Pa. For a short time, in 1917, he was Inspector of Ordnance for the U. S. Government, and the following year, having entered the U. S. Naval Reserve Force, he was ordered in a similar capacity to the Midvale Steel Co. In September, he removed to the Navy Yard, League Island, Philadelphia, to train for the obligatory minimum of six months' sea duty. There he contracted influenza, which was followed by pneumonia, from which he died, September 27, at the Navy Yard Hospital. Captain Braxton Bigelow* Captain Braxton Bigelow was the son of Major John B. Bigelow, U. S. A., retired, and grandson of the late John Bigelow, author, and Minister to France under President Grant. Captain Bigelow graduated

Jan 1, 1920

Raymond Weir Smyth, born Nov. 3, 1888, was the son of Herbert Weir Smyth, professor of Greek Literature at Harvard University. He graduated (A. B.) from Harvard in 1909 and later pursued advanced studies there in chemistry and in metallurgy. He held the position of metallurgist for the American Steel and Wire Co. at Worcester, Mass., and also for the Steel and Tube Co. at Youngstomn, Ohio. For a time he was inspector of munitions for the British Government and stationed at the Railway Steel and Spring Co. at Latrobe, Pa. For a short time, in 1917, he was Inspector of Ordnance for the U. S. Government, and the following year, having entered the U. S. Naval Reserve Force, he was ordered in a similar capacity to the Midvale Steel Co. In September, he removed to the Navy Yard, League Island, Philadelphia, to train for the obligatory minimum of six months' sea duty. There he contracted influenza, which was followed by pneumonia, from which he died, September 27, at the Navy Yard Hospital. Captain Braxton Bigelow* Captain Braxton Bigelow was the son of Major John B. Bigelow, U. S. A., retired, and grandson of the late John Bigelow, author, and Minister to France under President Grant. Captain Bigelow graduated

Jan 1, 1920

By A. C. Halferdahl

DURING a study of reactions involving iron sulfides, it became desirable to know approxi-mately the heat of decomposition of pyrite. The values given for the heats of formation of pyrite and ferrous sulfide are 35,500 calories and 23,070 calories respectively. For the reaction 2FeS2= 2FeS+S:, the heat effect would be-24,860 calories. But pyrite gives sulfur and pyrrhotite upon heating and the latter is a solid solution of sulfur in ferrous sulfide. The only meas-urements of this decomposition are those of Allen and Lombard1 of the Geophysical Laboratory who have measured dissociation pressures of both covellite and pyrite and have carefully reviewed the literature. They give a table of values for covellite as determined by Preuner and Brockmoller2 and by Wasjuchnowa3 and compare these values with their own measurements. The conclusion is that the measurements of Preuner and Brockmoller are seriously in error, while Was-juchnowa's values fit in well with those of Allen and Lombard. Wasjuchnowa's measurements were made by a dynamic method, while Allen and Lombard em-plowed a static method on both covellite and pyrite. Tables I and II reproduce the measurements of Wasjuchnowa and of Lombard and Allen on covellite and pyrite.

Jan 11, 1927

By W. J. Joslin

The frontal-advance equation can determine how the fluid withdrawal rate and subsurface operating pressure influence oil recovery from pressure-maintained reservoirs having characteristics favorable for efficient vertical segregation. For effective vertical segregation in formations having low dip angles, the requirements are: thick, massive sands, low viscosity oil and high vertical permeability with few discontinuous shale members. This approach has been successfully applied to the LL-370, which is a massive Eocene sandstone reservoir containing crude with an average gravity of 26" APT, a dip of only 3" and vertical permeability of ½ darcy. The average gas cap saturation was calculated for various rates of vertical gas-oil contact movement corresponding to a wide range of reservoir producing rates. This method also evaluated the effect of different pressure maintenance levels on oil recovery. Applicability of this procedure for calculating the present oil saturation in the LL-370 gas cap has been substantiated from field performance, where the oil saturation was computed by comparing oil recovery with the gas cap volume vacated. INTRODUCTION During the natural depletion history of the LL-370 reservoir, located in Lake Maracaibo, Venezuela, excellent vertical segregation resulted in the formation of a thin gas zone over a substantial portion of the oil-productive area. Subsequently, gas injection forced this thin gas-saturated zone slowly downward, reducing the oil saturation in the gas cap to a low value. The oil recovery has been raised considerably above earlier predictions where vertical segregation effects were under-estimated. In order to determine the maximum efficient producing rate and optimum operating pressure for this reservoir, a vertical gas frontal-advance analysis has been made through application of the fractional flow equation. LL-370 RESERVOIR CHARACTERISTICS The reservoir consists of a truncated monocline of massive. highly-permeable Eocene sandstone, called the B-b formation, covering an area of more than 13,500 acres. The original oil in place was 2.17 billion STB. Internal non-sealing faults subdivide the structure into four blocks called the B-6-x.6, 10, 11 and 13, which are effectively bounded by major faulting on the flanks, an unconformity updip to the west, and an immobile aquifer to the southeast. The producing formation occurs at an average depth of 5,250 ft subsea and has a closure of more than 1,500 ft. A typical producing section has a net oil sand thickness of 170 ft. Scattered throughout the section are a few randomly-positioned shale lenses which increase in thickness and areal extent downdip. The reservoir rock and fluid properties vary with depth. The permeability and produced oil gravity are 1600 md and 28" API at the top, compared to 300 md and 18° API at the water-oil contact. The productivity of updip wells is, therefore, much higher than the reservoir average. The reservoir oil was originally saturated at the crest, grading to a slight degree of undersaturation at the water-oil contact. There was no original gas cap; and material balance and the field performance indicate no water influx. Except for the northern B-6-x.6 block, the fluid and rock properties have already been published.' Average LL-370 reservoir properties are shown in Table 1. RESERVOIR PERFORMANCE UNDER NATURAL DEPLETION Fig. 1 shows production performance from 1939 to date. Early development was gradual, with 30 wells pro-

Jan 1, 1965

By W. E. Gaby

SINce the time of their discovery, the genesis of the ores at Mount Morgan, and the nature of the changes which have affected the surrounding rocks, have been the subject of investigation and speculation by geologists and mining engineers. Developments at this mine, for a long period the greatest gold producer of the world, show that with depth the orebody grades into copper, of which metal it now furnishes a large output, exceeding in value the gold. In earlier times, the purity of the gold and the first extremely heterogeneous character of the ore made it an interesting problem. Now, the probable depth of the copper enrichment, genesis, and true relations of the neighboring rocks furnish equally profitable material for investigation, and the present somewhat detailed description of these ores and rocks, from microscopic study, may prove of interest. , The mine occupies a highly silicified portion of a belt of quartz-porphyry, which is believed to be the oldest rock of the region. This belt of quartz-porphyry and allied rocks runs north and south between two areas of a later intrusive granite, as shown on the geologic map,' Fig. 1. Near the orebody the quartz-porphyry has been intruded by a dense basaltic mass called the " Old Basic." Cutting all three of these igneous masses are two sets of basaltic dikes, one running northwest-southeast, and the other, cross dikes, northeast-southwest. These dikes may be contemporaneous with, instead of later than, the ore. Their number has caused peculiar difficulties in extracting it, as the clay selvage of decomposed material affords no adhesion between dike and ore, causing great blocks to loosen and come down. The investigation was based on specimens furnished by B. Magnus, former general manager of the mine, and notes on the areal geology by

Jan 1, 1917