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By L. Edeleanu

Crude petroleum is a mixture of various groups of hydrocarbons and some bodies containing oxygen or sulphur.

Jan 1, 1915

FOR this Famous Mining Enterprise issue MINING ENGINEERING selected the company that started the zinc in dustry in the United States. The New Jersey Zinc Co. has been a supplier of zinc products to the nation's industries for more than 104 years. Its Horse Head trade mark is famous throughout the world.

Jan 12, 1953

By H. P. Leighly, F. C. Perkins

THERE have been several statements in the literature about the difficulty of producing single crystals of high-purity (99.99pct) by the strain-anneal method. Consequently, investigators tend to employ low-purity aluminum for their single-crystal experiments, or else resort to the Bridgman or other techniques which depend on solidification for the production of single crystals. The following paragraphs describe a solid-state method for the manufacture of single crystals of high-purity aluminum which should provide crystals with greater perfection than those formed by solidification. The starting material for this method of producing single crystals was secured from the Aluminum Corp. of America and has a purity of 99.99 pct, the balance being trace amounts of impurities. Specimens approximately 1 by 4 in. are sheared from sheet having a nominal 0.050 in. thickness. The specimens are given a preliminary anneal at 640°C for approximately 3 hr in order to remove fabrication strains and to produce an average grain size of about 1/4-in. diam. The specimens are then etched in Tucker's etchant (45 pct HC1, 15 pct HNO3, 15 pct HF and 25 pct H2O) to remove the oxide film. Critical strain is applied by wrapping each specimen about a 1 3/4 in. round and subsequently straightening it against a flat surface. The high-purity aluminum sheet is sufficiently soft that this operation can be accomplished by ordinary finger pressure. The specimens are immediately annealed again at 640°C for 3 hr and reetched for examination. Ordinarily, considerable growth of certain of the grains will have occurred, and occasionally a single crystal will be produced on the first attempt. The procedure of alternately straining, annealing and etching is repeated until the majority of a batch of specimens contains usable crystal sizes. Typical examples are illustrated in Fig. 1. The greatest changes in crystal sizes are produced in the initial treatments. As the average crystal sizes get coarser in the later treatments, the sever- ity of the strain must be increased in order to produce grain boundary- migration. This increase in severity is effected by decreasing the diameter of the round used for straining (to 1 1/2 in., for example) and/or wrapping the specimens about the round twice, with opposite faces in contact with the round, before flattening. Usually the strain treatments described are not severe enough to produce nucleation in coarse grain high-purity aluminum. The growth of grains occurs by strain-induced grain-boundary migration. It has been observed that the grain boundaries move most readily during the first hour or so of each annealing treatment and that the rate of movement decreases with extended holding times at temperature. Prolonged annealing treatments are therefore not usually beneficial. Similarly, the rate of growth of each crystal appears to depend upon the orientation of the crystal with relation to those of its neighbors. Frequently island grains are formed after the initial heat treatment as the result of slow grain-boundary migration. These sometime become stationary during later heat treatments. Twin orientation interfaces are frequently developed during annealing. These imperfections can usually be removed by increasing the severity of strain to produce actual nucleation of new grains of more favorable orientation at the imperfection interfaces. The largest single crystals produced in our laboratory by the above method measured 4 by 1 by 0.050 in. Examination of Laue back-reflection patterns from a limited area of the specimens, gave no evidence of polygonization. Probably there is some indication of polygonization in the original grain area provided a more sensitive technique is used for detection. Experiments to produce wider specimens were less successful, possibly because wider sheets increase the complexity of the strains induced by deformation and promote widespread nucleation. Grain boundary migration occurs preferentially in a direction parallel to the longitudinal axis of the specimen. The choice of specimen geometry with respect to the rolling direction of the sheet appears to be immaterial in regard to the production of single crystals.

Jan 1, 1961

By David Thomas

The preliminary meeting to organize the American Institute of Mining Engineers was held last evening. The attendance was unexpectedly large, and the proceedings were harmonious. According to present appearances, the Institute is destined to have a vigorous and influential career. A noteworthy feature is the interest manifested by the owners and operators of mines and by mining foremen, who are not strictly engineers. Provision is made in the rules for such persons, and all others who desire to be connected with the organization, by the establishment of a class of associates, having all the privileges of members, with a very few restrictions. It is ordained that the President, four of the six Vice-Presidents, and six out of the nine managers, shall be professional mining engineers, this term including metallurgical engineers also.

Jan 1, 1971

By W. Julian Parton

General Crushed Stone Co. operates a dozen quarries in such rock types as gabbro, basalt, granite and limestone. Drilling characteristics and problems vary from one operation to another so that a variety of equipment and methods must be employed. In addition, it has been found that equipment improvements make it advisable to continuously look for and experiment with new machines and accessories. This article discusses drilling progress at some of the Company's more interesting operations.

Jan 1, 1963

By H. M. Roche

IN the first section of- this article, published- Feb. 4, the author reviewed the his¬tory of iron ore mining in New Jersey, listed the reserves and possible markets of this ore, and discussed the role of Lake Superior and foreign ores in domestic steel production. This concluding section of the article emphasizes the metal¬lurgical value, future markets and mining coats of Jersey ores. Mr. Roche's thesis is that industry can profit both metallurgically and econom¬ically through a greater use of Jersey ores --that these orebodies are as yet prac¬tically unexploited, and con¬stitute a valuable national re¬serve fully worthy of careful consideration by Mid-West¬ern steel makers.

Jan 1, 1937

By William L. Fink, Dana W. Smith

Approximately two years ago the authors obtained data that indicated that initial precipitation could not be detected by change of lattice parameter in the aluminum-rich aluminum-magnesium alloys. Some of these data were first published in a brief note in Mining and Metallurgy'. Cast specimens were used at that time and they showed initial precipitation relatively sooner than sheet material of the same composition. For this reason a more thorough investigation has been carried out using a homogenized aluminum-magnesium sheet corltairling approximately 10 per cent magnesium. Materials.—The aluminum used in the preparation of the aluminum-magnesium alloy was of high purity, containing less than 0.01 per cent each of iron, silicon and copper. The magnesium was high-purity sublimed magnesium. Preparation of Alloy.—Approximately 4 kg. of the aluminunl was melted in a plumbago crucible in an electric furnace and the magnesium was added. The melt was thoroughly stirred with a graphite rod and fluxed with chlorine gas before casting. The alloy was cast in the form of a sheet ingot in a cold iron tilting mold (approximately 200 by 165 by 40 mm.) and into small chill-cast slabs for chemical analysis (75 by 40 by 5 mm.). The chemical analyses were made upon drillings from the analysis slabs. The analytical methods were those described in "Chemical Analysis of Aluminum," published by the Aluminum Company of America. The composition of the alloy was found to be: magnesium 10.30, silicon 0.013, iron 0.008 and copper 0.005 per cent. In order to insure homogeneity the alloy was given two intermediate anneals at 430' C. for a total time of 36 hr. The ingot was hot-rolled

Jan 1, 1937

By G. E. Kedzie

The ore-deposits of ail that portion of the San Juan country within the borders of Ouray County are either in the tertiary ernptives or, confined to a relatively narrow zone, in the sedimentary beds just beneath them. The ore-deposits in the igneous formation

Jan 1, 1888

Jan 1, 1923

By Charles Will Wright

THE HIGHLY SPECIALIZED heavy air transport services to mining regions, such as exist in the New Guinea gold fields and in northern Canada, have been even more essential in the development of mines in Peru. Few nations have been con- fronted with greater natural obstacles to transport than has Peru, and without the plane it would have been impossible to get the machinery and supplies for the construction of power plants and mills to many of these interior mines, situated as they are over high mountain ranges, with muleback the principal means of transportation. As the mines within a district become important producers and warrant the expenditure, the mule trail is being replaced by automobile roads to connect with the railway stations and with the airports.

Jan 1, 1940

By C. H. Burgess

ON June 5, 1947, Secretary of State George C. Marshall in a speech at Harvard University outlined a plan for the economic recovery of Europe. The plan contemplated that the United States should provide assistance which would enable the European nations better to help themselves and to help each other to reconstitute from their war-torn lands conditions which would make possible decent standards of living.

Jan 1, 1950

By C. A. Pierce

UNDERGROUND operations of the United States Potash Co. at its mine near Carlsbad, N.M., have been continuous since the property was opened about five years ago. Approximately one million tons of potash has been mined and two shafts have been sunk, each to a depth of about 1000 ft. Outstanding in the company's operations is the fact that not a single blasting accident has occurred during the aforesaid period. The purpose of this paper is to describe the blasting practice that has made possible the achievement of this accident-prevention record. The mining method employed in extracting the thick horizontal bed of potash may be described as a double-entry room-and-pillar system. Mine development is kept well in advance of extraction operations, and a three years' supply of ore, at least, is always available. Limits of the orebody have not been determined, and in the present system of mining headings are advanced by a "shortwall" method. This was the first potash ore bed developed in the United States. The nature of the deposit, therefore, was unknown, and it was deemed expedient to outline a conservative mining policy. Later, when more is known about the deposit and certain control ascertained, a "longwall" panel retreating method may be found advisable. The necessity for a domestic supply of potash became a national issue previous to and during the World War. The United States Govern-ment came to realize that this country should not be dependent upon foreign sources of potash, and began extensive explorations in many parts of the country, seeking an orebody that would meet the exacting require-ments of the domestic market. The Department of Interior, through the Geological Survey and Bureau of Mines, made every effort to determine the location of potash deposits and encouraged their exploitation by private capital. Through the combined efforts of the Department of Interior and private industry, the deposit now being worked by the United States Potash Co. was discovered and brought into production.

Jan 1, 1936

By Benjamin Smith Lyman

It is a time-honored saying in the anthracite region that " under the conglomerate there is no coal;" and the adage is generally reckoned a sure guide in coal-exploration. Yet there are many places where conglomerate, even coarse conglomerate, occurs above important coal beds, and, among others, above the great Mammoth bed. One of the most striking of such occurrences is on the Shippen and Wetherill tract, half a dozen miles west of Tamaqua; and it illustrates remarkably the disastrous effect of a too unquestioning blind confidence in the sweeping literal truth of a broad generalization. Here there is a conspicuous crag formed by a twenty-foot bed of egg-conglomerate, dipping 60 degrees southerly, and jutting out boldly at the western end of a hill, where it is cut through by the small stream of Little Creek. The hill runs eastward for half a mile, with occasional exposures of pebbly rock along the western half of the crest. Eastward from the exposures lies the old Kentucky Bank mine, abandoned thirty years ago, where the Mammoth bed was worked down to water-level through a space of a mile and a quarter westward from the Palmer tunnel to the very edge of the

Jan 1, 1893

By Peter Kos

Since advances in the understanding of gravity thickening reflects the development of knowledge about suspensions themselves, the paper starts with the discussion of flocculent and nonflocculent suspensions. The properties of flocculent suspensions and their behavior in different concentration regions (zone settling, channelling, compression) are defined and discussed. In the main portion of the paper, the behavior of flocculent and nonflocculent suspensions during batch as well as continuous thickening, is presented, together with a brief review of the gravity thickening theories and sizing methods. The classical as well as the most recently developed methods are presented and their use and limitations are discussed.

Jan 1, 1980

By Jon J. Connor, Richard J. Ebens

The trace element geochemistry of the cherty clay-rich carbonate residuum cover in much of southern Missouri and adjacent parts of Arkansas was investigated during the earl 1970's as part of a statewide geochemical survey of Missouri.1-8 The study was environmentally oriented and focused on the character of the "natural" geochemical environment of the state. A great deal of effort was made to collect samples that would represent the geochemical variability of the near-surface environment in an unbiased way. In general, this was accomplished by use of randomization procedures in both collection and analysis. Most of the sampling sites were selected randomly to prevent personal bias from entering into sample selection. In the laboratory, samples were analyzed in a randomized sequence to circumvent the effects of any systematic bias that may have entered into the laboratory procedures. Several residuum samples contained 1000 parts per million (ppm) or more of lead, zinc, and barium. All these samples were collected in Washington County in or near the barite district. The frequency distributions shown in [Fig. 1] indicate just how unusual the residuum in Washington County is with regard to these three metals and copper. The shaded parts of the histograms represent the samples from Washington County. The histograms are based on analyses of 141 samples from 38 localities scattered over the subcrop of the Cambrian and Ordovician formations of southern Missouri and northern Arkansas. Eight localities were selected randomly from over each of four bedrock units-Bonneterre dolomite; Potosi and Erninence dolomites; Roubidoux formation; and the Jefferson City, Powell, and Cotter dolomites. Six localities were selected randomly from over the Gasconade dolomite. The geochemical "background" for these elements in residuum is defined by samples from outside of Washington County (unshaded part of the histogram); lognormal distribution curves have been fitted to the corresponding parts of each histogram. Clearly, these lognormal models (curves) describe well the background distributions of zinc, barium, and copper. The background histogram of lead concentrations is notably skewed to the right compared to the model. Lognormal distribution curves were also fitted to the data on lead, copper, and zinc in the residuum of Washington County. No model was fitted for barium in Washington County because of the distinct bimodality in the data. All samples containing more than 1000 ppm were collected in the barite mining district and obviously reflect the elevated levels of barium in the district. The frequency distributions for Washington County are clearly anomalous with respect to the background data, those for lead, zinc, and barium being exceptionally so. The models for anomalous lead, zinc, and copper seem to fit reasonably well, although the scatters in the lead and zinc anomalies are considerably larger than the scatters in the corresponding background data. The copper anomaly, although probably real, is greatly subdued compared to that of lead and zinc. Also, it has a scatter similar to that of the copper background, rather than being enhanced like the scatters of the lead and zinc anomalies. On the basis of techniques described by Miesch,4 the chemical abundance of copper, lead, and zinc in residuum in

Jan 1, 1980

By P. D. I. Honeyman

Changing trends in concentration, involving regrinding with the subsequent production of a finely divided, high-grade flotation product, presents a real problem to the modern copper smelter. In the treatment of such a material, handling difficulties are numerous and potential possible losses may be very great. In many plants, of course, preliminary roasting of the furnace charge remains an economical necessity. Under such circumstances, the operator has no alternative except to follow orthodox roaster reverberatory practice, though taking all possible precautions to avoid excessive dust losses and bad working conditions. In other plants, roasting is not only unnecessary but would be highly undesirable, and at best the charge would be merely dried before entering the reverberatory furnace. In the latter case the possibilities of raw charging loom large. The Miami plant of the International Smelting Co. handles the entire output of concentrates of the several mining companies operating in the Globe-Miami district. All of these companies produce a flotation concentrate which, at the Miami Copper Co. particularly, is all reground and is high in grade. In addition, the Inspiration Copper Co. ships a substantial tonnage of high-grade cement copper to the smelter from its leaching plant. Following the flow sheet of the original plant, all such material received was bedded, dried in Wedge furnaces and smelted in reverberatory furnaces. At times during the history of the plant it has been necessary to carry the drying operation further, to a partial roast, before reverberatory smelting. Since the charge contained over 80 per cent flotation concentrates, the handling of which in a dried condition was at best a dusty job, unusual precautions were taken to cut down dust losses. The Wedge furnace plant was equipped with a Cottrell treater and all hoppers and calcine cars were carefully designed to cut down dust loss in transferring the so-called calcine from hoppers to car and from car to furnace. In the furnace itself the dusting problem was a severe one. Arch erosion was very rapid and flues and waste-heat boilers rapidly filled up with a partly smelted flue dust.

Jan 1, 1934

By James H. Courtright, Kenyon Richard

TOQUEPALA is a porphyry copper deposit in which mineralization is localized by a large breccia pipe formed in dose genetic relation to intrusive rocks. The deposit is in southern Peru, 55 airline miles north of the small city of Tacna and the same distance inland from the port of 110. Quellaveco and Cuajone, geologically similar deposits, lie 12 and 19 miles north of Toquepala. Chuquicamata is 400 miles to the south. The deposit is high on the southwestern slope about 20 miles from the crest of the Cordillera Occidental of the Andes Chain. It lies in a mountainous desert where the steep southwesterly slope of the Andes is dissected by a succession of rapidly downcutting, deep canyons. Local topography is moderately rugged with a dendritic drainage pattern and an elevation of 8000 to 14,000 ft. Volcanic peaks along the crest of the Cordillera rise over 19,000 ft.

Jan 2, 1958

By Thomas E. Ban, Charles D. Thompson, Charles A. Czako

Continuous sintering-a metallurgical process for more than 50 years-has broadened from its origin in nonferrous metallurgy to present-day applications in ferrous, chemical, and nonmetallic fields. During the past year, self-fluxing sinter production has been a subject of active interest to iron metallurgists in North America. Accomplishments however, have come predominantly from Europe and proper interpretation of these reports requires an understanding of European raw materials and European economics. The technology, of course, can be applied universally.

Jan 10, 1959

By John K. Dienes

The permeability of sands and soils seems to be adequately de- scribed by Darcy's law, but the permeability of rocks is complicated by a number of factors related to the probability of crack intersections. During the last few years we have developed a statistical theory of fragmentation which has been successful in explaining the observed behavior of rocks. In this paper, a theory of permeability is developed which draws on the concepts employed in previous work. The permeability involves three factors, the average fluid flux per crack, the number of cracks per unit area, and the fraction of cracks that are not isolated. Probabilistic ideas are used in connection with the hydrodynamic theory of flow through a single crack to develop an integral expression for permeability. The result has the form of Darcy's law for anistropic media. Although the current work is motivated by the need to develop optimized oil-shale retorts, we believe that the theory can be applied to a variety of other problems.

Jan 1, 1982

By W. R. Hibbard, J. D. Nisbet

The high temperature properties of Fe-Cr-Co-Ni base alloys and the effects of hardening element additions on these properties are rationalized on the basis of general principles of alloying. DURING the past few years the base elements in high temperature austenitic alloys have gradually been changed from iron-rich materials to nickel-rich, then to cobalt-rich and more recently to various iron, cobalt, and nickel combinations, all with an approximately constant chromium content of 20 pct. Concurrently, the hardening additions of the incongruous* elements, have been shifted from small amounts of a single element to various ratios of molybdenum, tungsten, columbium, carbon, titanium, and aluminum with the percentages of these constituents continually increasing. It has been known that the typical soft high temperature alloy (such as Inconel) consisted of face-centered cubic austenite, but the effect of varying the composition of the base elements, iron, chromium, nickel, and cobalt, has not been broadly analyzed. Therefore, it was reasoned that the first major problem in the understanding of the properties or the further development of high temperature alloys was to study systematically the effect of composition upon the mechanical properties of face-centered cubic Fe-Ni-Co-Cr austenitic solid solutions. The matrix of the strong high temperature alloys (such as Inconel X) is usually also a face-centered cubic solid solution of iron, nickel, chromium, and cobalt but with additional phases which can be generally classified as intermetallic compounds and carbides. It is usually observed that combinations of the hardening elements, tungsten, molybdenum, columbium, tantalum, titanium, aluminum, carbon, and others have been used in these strong high temperature alloys. Thus, it was reasoned that a second major problem in studying these alloys was to understand the effect on mechanical properties of adding

Jan 1, 1954