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By I. C. White

Only two factors appear to be directly responsible for the geographic distribution of sulfur in the coal fields of West Virginia: these are the stratigraphic position of the coals in question, and the eastward or westward location of the deposits. There appears to be a progressive increase in the sulfur content of West Virginia coals from the oldest Peqnsylvanian deposits in the Pocahontas, New River, and Kanawha Groups of the Pottsville Series up through the Allegheny, Conemaugh, and

Jan 1, 1920

By ElRoy Nelson

WATER provides to many mineral industries functions similar to those performed by money in the economic system. Water is a medium of exchange. It is also required in chemical reaction for cooling, for transfer of minerals, and for cleaning. To a great extent, water is also a raw material in almost every industrial operation; it becomes a component of the finished product. In the Rocky Mountain region, water is treated with a great deal of respect. There has not been enough of it when needed. Long ago storage facilities were planned and devised to assure a supply during periods of shortages. This comes from the history of the region in irrigation and mineral processing. Within this region the shovel was always the most lethal weapon used in settling disputes over the use or misuse of water.

Jan 10, 1954

By L. D. Lash, J. R. Ross

Scandium is a pseudo-rare earth which is truly rare and expensive. It has special properties which may make it desirable even at the present price of $2750 per lb. Recently the price was lowered from $5000 per lb which had prevailed since 1952, and it is anticipated that usage will be stimulated because of the lowered price. This metallic element is distributed widely in trace amounts in the rocks of the earth's crust. In addition to micro-amounts found in most uranium ores, concentrations of 50 to 100 ppm have been found in Colorado ferberite ore, lateritic nickel ore, heavy sandstone from Utah, Wyoming, and New Mexico, and various zircon sands and monazites from the western part of the US. Scandium has been found as an essential constituent of very few minerals, the most important being thortveitite, a scandium silicate. At the present time, this mineral commands a price more than twice that of gold.

Jan 8, 1961

By Colin G. Wilson

This paper considers the heavy liquid laboratory tests used to determine the amenability of a potential ore to the heavy media process. The results of the laboratory testing are correlated to actual plant performance and establish design parameters for the heavy media process. These parameters are used in the development of the metallurgical flow sheet and in the sizing of equipment in the metallurgical plant design.

Jan 1, 1978

By Clement K. Chase

ION exchange recovery of uranium has been proved successful in many operating plants in various parts of the world. First used in column plants processing clear liquors, ion exchange has more recently been applied in basket resin-in-pulp systems. A logical further development is the application of truly continuous processing techniques to the ion exchange recovery of metals, since previous systems have been semicontinuous at best. Column ion exchange is a valuable technique and has been used extensively in South Africa and elsewhere. However, it requires clear liquors. To produce these clear liquors, considerable investment in filter plant and clarification equipment is necessary. In the cases where it is very difficult or impossible to produce clarified liquors, column ion exchange is not so useful. Moreover, some liquors suffer from post-precipitation after clarification, which can become a serious problem.

Jan 9, 1957

By William B. Phillips

It would be hard to find a mineral region that has been more beset with " processes" for the extraction of gold from auriferous sulphides than North Carolina. And it would be hard to find a mineral region less sought by capital. So many promising mines have come to grief here (perhaps because they were too "promising"), SO many "processes" have been tried and abandoned, so much expensive machinery has been bought and thrown aside, that to invite money here for investing in gold mines is almost sure to cause a smile of incredulity, or a sigh of disappointed hopes. Within the writer's personal knowledge, at least five disastrous failures have followed the introduction of as many processes. It would seem as

Jan 1, 1889

By V. Miller

Highly variable milling procedures within a geologically complex porphyry copper deposit owned by Kennecott Corp. in Nevada made it necessary to estimate copper recovery and concentrate grade in areas where actual test data was lacking. Estimation was made by first determining the relationships between desired metallurgical properties and the ore's petrology-copper mineral type, rock type, and copper grade. This relationship was then combined with previously estimated rock type, mineral type, and copper grade data in the mineral block model to predict milling properties.

Jan 1, 1985

By B. H. Bergstrom, W. Mitchell, C. L. Sollenberger

D. W. Fuerstenau (Associate Professor of Metallurgy, Dept. of Mineral Technology, University of California, Berkeley, Calif.) and D. A. Sullivan, Jr. (with the University of California) — Messrs. Bergstrom, Sollenberger and Mitchell have shown in two excellent papers that the energy per unit mass required for the breaking of spheres is inversely proportional to the size modulus of the fragments of the broken spheres. They found that the fragments of spheres broken within a steel enclosure were finer than those produced by breaking spheres encased in gelatin. This results from utilization of part of the strain energy at fracture for secondary breakage. For spheres not encased in gelatin, these authors found that after fracture the fragments of the spheres possess kinetic energy amounting to 45% of the strain energy needed for initial fracture. Breakage of a sphere in gelatin results in waste of this kinetic energy, whereas breakage inside the steel container makes use of this kinetic energy for further size

Jan 1, 1962

By Kenneth Seaver

Discussion of the paper of KENNETH SEAVER presented at the San Francisco meeting, September, 1915, and printed in Bulletin No. 105, September, 1915, pp. 1913 .to 1927. J. W. RICHARDS, South Bethlehem, Pa.-This paper concerns a very large industry, and an important detail in that industry. Within sight of where I live in Bethlehem, Pa., are coke works in which $2,500,000 was lost by the use of improper bricks in the coke ovens. This was the fundamental reason of the failure of the plant. The old ovens have all been torn out and replaced by new ovens built of proper bricks. This may emphasize the commercial importance of this subject. When speaking about coke-oven brick, the first thing that comes to my mind is how important it would he if it were possible to. get a brick of better heat conductivity. The heat for coking coal has to go through the thickness of the brick. The silica brick used has low heat conductivity as compared with some other refractories; magnesite brick probably has four times its heat conductivity. The coke oven needs bricks of high heat conductivity. Any process which would increase the heat conductivity of silica brick would undoubtedly shorten the coking process.

Jan 12, 1915

Jan 1, 1944

By E. H. Ahrens

This paper deals with the responsibilities of an operating geologists and the relationship of operations to exploration. It should be of interest to those soon to enter the profession, those new to mining geology and as a review to more experienced geologists. Subjects discussed include detailed geologic mapping, sampling, core logging, assaying, selection of proper map scale, posting geological and assay data, section preparation, identification of ore controls, delineation of development drill targets and geologic hazards, models and the very important topic of salesmanship. Methods and ideas, proven valid in vein, pyrometasomatic replacement and porphyry copper deposits are presented. Hopefully, these will smooth the path for new members of our profession.

Jan 1, 1984

By Gail Moulton

THE oilfields in Illinois are located principally along the LaSalle anticline in the southeastern part of the state. The oil produced comes most largely from beds of Pennsylvanian and Mississippian age, but there is an increasing important production from deeper horizons, as will be noted under new development. The oil is largely of paraffin base, and has an average specific gravity of about 35° Baume. The rank of Illinois as an oil producer has dropped from third since 1913, when its production was exceeded only by that of California and Oklahoma, to eighth in 1923. This has been the result of failure to find new pools of considerable size to offset the declining production of the old wells and of the greatly increased production of some of the other states. The noteworthy features of petroleum production in Illinois during 1924 are: the low rate of decline for the state as a whole; the smaller percentage of dry holes; and the larger average initial yield of the new wells.

Jan 3, 1925

By A. N. Mitinsky

Discussion of the paper of A. N. MITINSKY, presented at the San Francisco meeting, September, 1915, and at the New York meeting, February, 1916, and printed in Bulletin No. 104, August, 1915, pp. 1697 to 1705. ALBERT SAUVEUR, Cambridge, Mass.-The author expresses the belief that steel will not fail under fatigue when subjected to ultimate stresses unless the stresses exceed the elastic limit or the limit of proportionality. I think this statement is contrary to the evidence. It is conceivable, however, that a stress ever so small does produce a permanent set, although so slight that we cannot detect it with the instruments at our disposal. Nevertheless the repetition of this small stress a great many times will finally break the piece and the nearer, we approach what we call the elastic limit, the quicker will the piece break under fatigue. J. W. RICHARDS, So. Bethlehem, Pa.-I would like to ask Professor Sauveur whether there is a similar indefiniteness about the limit of .proportionality as there is about the elastic limit. ALBERT SAUVEUR.-Yes; I believe it also depends upon the delicacy of our instruments. J. W. RICHARDS.-If that is so then we are as badly off by adopting the limit of proportionality as a criterion as we are by adopting the elastic limit.

Jan 5, 1916

By R. P. Killmeyer, B. S. Gottfried, J. T. Wizzard

The US Department of Energy's Coal Preparation Branch has developed a computer program to calculate the performance characteristics of coal washing devices. This program uses specific gravity analyses of the clean coal and refuse streams as input, and generates dependent and independent performance criteria for the washer. Partition curves are internally represented in a functional form by a Weibull function. Comparisons are made between performance criteria calculated by hand and the performance criteria calculated by the program for 120 different dense medium cyclone tests. Results show that the computer program gives results in close agreement with hand-calculated values while greatly reducing the amount of time involved in performing the analyses.

Jan 1, 1984

By L. Michael Kaas

The mineral industries are striving to expand their use of the computer's ability to process exploration, geologic, and mining data. Digital plotting programs and devices are continuing to gain wider use for lowering the cost and the time required to produce many types of maps and cross-sections commonly used by mining companies. Mineral engineers and geologists will soon be using a new tool, computer graphics, to greatly facilitate the use of computers to solve a large number of industry problems. By means of cathode-ray-tube (CRT) displays, an engineer can search large files of geologic data; display elevation contours, geologic structures, and ore grades; construct geologic and mining cross-sections; and compute tonnages for mining plans or ore reserve estimates. Examples of both digital plotting and cathode-ray-tube problem solving approaches are discussed in this paper.

Jan 1, 1969

By N. B. Aughenbaugh, W. C. Patrick

The availability of a thorough, simple-to-use roof fall classification system is desirable for several reasons. First, such a system would expedite the reporting of falls for the purposes of estimating material removal costs, analyzing damage levels, and complying with federal regulations to report falls in certain areas of the mine. Second, the classification system would allow the mining engineer to record falls routinely with little time and effort expended. This would encourage him to make observations concerning what type of roof support would work best in a given situation. Third, and probably most important, an

Jan 3, 1979

By William C. Peters

The pre-production interval, beginning with the recognition of an orebody's best potential and ending with significant production, contains time-dependent conditions well appreciated by miners but not always understood or appreciated by the landowners, investors, and legislators with whom a miner must deal. The expression persists, even outside of Western fiction, that someone has "found a mine." From a slightly more knowledgeable position, the question is asked "How long does it take to make a mine?" and an all-encompassing answer is expected. By scanning the discovery and development history of hundreds of mines and rejecting those which involve rehabilitation or expansion of older mines, some generalizations can be attempted. It should be kept in mind that while physical conditions involving the geology of the orebody and the geographic surroundings do not change markedly with time, technologic and economic conditions do change from year to year. The new methods, facilities, markets, land tenure, and politics form a pattern in which today's mines are made and which do sometimes modify the pre-production interval.

Jan 8, 1966

The income of the Institute is derived mainly from dues, advertising in MINING AND METALLURGY and sale of publications. These sources are fortunately supplemented by the interest from invested funds now amounting to over $500,000, a considerable portion con- stituting endowments for especial purpose?s. Aside from the medal funds the principal endowments are the James Douglas Fund for support of the Library, the Rocky Mountain Fund and the Seeley W. Mudd Memorial Fund. The income from the two last named is available for the support of research and a variety of other purposes. It is allocated by the Board of Directors upon recommendation of standing committees in each case. An active effort is being made to increase the endowments of the Institute, it being felt that unusual opportunities exist for research and public and professional service through the organization.

Jan 1, 1937

By J. Menashi, D. A. Douglas, A. S. Rappas

A process has been developed for recovering the refractory metals chromium (Cr), vanadium (V), molybdenum (Mo), and tungsten (W) in mixed secondary source materials, such as contaminated grinding wastes. The wastes are calcined with sodium carbonate in air to yield water-insoluble oxides of the base metals iron (Fe), nickel (Ni), cobalt (Co), and copper (Cu) and water-soluble salts of the refractory metals. An aqueous leach separates these two classes of metal values. Cobalt, nickel, and copper can be recovered from the oxidic residue by conventional processing methods. The leach solution is purified and then treated to recover the refractory metals. The process can accommodate a wide range of feed compositions and generates a minimum of aqueous effluents.

Jan 1, 1985

By F. R. Jones

T Tahawus, N. Y., National Lead Co. operates the MacIntyre development. Here the world's largest titanium mine produces 5200 long tons of ore per day and pours 8000 long tons of waste rock over its dumps. Concentrated ilmenite is sent by rail to National Lead Co. pigment plants, and a second product, magnetite, is sold to steel producers in raw form or is agglomerated and shipped as sinter. Several earlier attempts had been made to produce iron from the deposits, which have been known since 1826. These attempts failed, chiefly because of titanium impurity. In 1941 the present owners re-established the operation for production of war-scarce ilmenite, and the impurity became the main product.

May 1, 1956