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ON Coal's Horizon one development rises above all others. That is the swift expansion of output to make Soviet Russia the largest coal producer on earth next to the United States. Few Americans are aware of the speed and extent of that expansion nor of the accompanying creation of a strong, resourceful mining machinery industry, nor of the extent and character of the mechanization of Soviet coal mining. Two initial clarifications are necessary for better understanding. First, we must keep in mind the sharp distinction between the Russian people and the communist Soviet dictators who rule them. The great mass of the Russian people are not members of the Communist Party as people here are Republicans or Democrats. They are not permitted to be members. There are, by various estimates, only 2 to 4 million members of that party in all Soviet Russia. The other 196 to 198 million are the victims of their tyranny and their terror. It is the activity of the Soviet rulers that concerns us here.

Jan 1, 1954

Open pit operators have found the dropball crane a great aid in cutting costs and hazards of secondary breakage. But a common problem in using the unit has been with the shock absorbing connection from the cable to the dropball itself. Blair Limestone Div. of Jones & Laughlin Steel Corp. has come up with a new connector to solve this problem and to save the time usually lost in frequent replacement of the cable slings, chains, or old tires hitherto used at this point. J&L personnel solved the problem by combining three ideas from other dropball crane owners. Their unit consists of two long U-bolts running through a heavy spring originally made for use on a vibrating screen. Heavy duty swivels attached to the bent ends of the U-bolts provide attachment points for the crane cable and the special chain to the dropball. Connection at the dropball is by an eyelet welded directly into the mass of steel, and a special alloy chain is connected to this with a clevis.

Nov 1, 1955

By Joseph W. Murray

Prior to 1950 Magma's ore production came from two parallel, steeply dipping, east-west striking mineralized faults, one called the Main or Magma vein and the other the Koerner vein, which lay about 1100 ft to the south. This vein system has been explored and mined over 9000 ft horizontally and 4800 ft vertically. In 1950 continued exploration led to the discovery and development of replacement orebodies in the Devonian limestone zones adjacent to the veins. These replacement deposits occur in the eastern part of the Magma mine and follow the strike and the 30º east dip of the host limestone. Strike length of the ore bodies varies from 250- 500 ft and thickness from 15-125 ft. The orebodies are large tabular masses with chalcopyrite and bornite being the dominant ore minerals. Hematite and pyrite are the most abundant gangue minerals. Incompetent limestone, shale, or a porphyry sill hanging wall is characteristic of portions of the replacement beds. In many instances the ore is blocky, badly fractured and intermixed with layers of limestone gouge, pyrite and hematite.

Jan 6, 1973

By Michael B. Gross

A numerical study of the vulnerability of unlined tunnels in jointed rock has been performed with the STEALTH computer program, using the CAVS model for jointed rock. CAVS, for Cracking And Void Strain, is a constitutive model that can simulate the initiation/propagation of fractures and the slip along fracture planes in a jointed rock mass. The CAVS model is unique because it represents a spatially oriented approach to rock failure, rather than the traditional invariant formulation, and because the CAVS submodels for slip friction and slip-induced dilatancy are used to represent the weakening influence of joints, rather than applying ad hoc modifications to the elastic moduli of the host rock. The CAVS model, as embedded in the STEALTH computer program, has performed numerical simulations of tunnel collapse at high overstress levels. These calculations show that the ultimate strength of the tunnel depends strongly on the joint properties, and that the results of the calculations are in qualitative agreement with the observed data for collapse of a tunnel in tuff.

Jan 1, 1984

By R. T. Hukki

THE accepted basis of comparisons between mills of different diameter is the percentage critical speed. [ ] In the following analysis capacity, T, is expressed in short tons per hour, tph, and power consumption, P, in kilowatts, kw. Accordingly power consumption per unit of capacity, Po, will be expressed in kilowatt hours per short ton, or kw-hr per ton. In all equations D refers to the inside diameter of the mill in feet and v to the peripheral speed of the mill in feet per minute inside the liners. Comparison between separate mills must be based on equivalent grinding conditions, i.e., same feed, same size distribution of feed, same size distribution of product, and same percentage of solids. In addition, comparisons between separate rod mills must be based on the same rods, same type of liners, and same percentage rod load. Comparisons between separate ball mills presuppose the same balls, similar liners, and same relative ball load. The practical np-range through which the equations apply varies, being narrower for fine grinding in ball mills and wider for coarse crushing in rod mills.

Jan 7, 1954

By John D. Wiebmer

Kansas, with its thin seams and tough overburden, may not be anyone's first choice for a coal mining operation. But there are operators making it pay through careful attention to mining techniques and aggressive marketing in the local region. One of the few Kansas coal operators is Bill Patch, who has been in the business for 28 years. Beginning with a single dragline operation near his home in Welch, Okla., Bill's Coal Co. weathered some lean times during the "soft" coal market of the 1950's and 1960's. But his tenacity paid off when new markets began opening up, and the company has grown by leaps and bounds in recent years. In 1975, the Fort Scott mine opened in Bourbon County, Kansas; in 1976, the Porter mine began production in Wagoner County, Okla.; in 1977, the Fulton mine opened near Fulton, Kansas. In addition, the original Welch mine in Oklahoma is still a producer, and this year the company will open a new mine at Chetopa, Kansas.

Jan 9, 1978

By Carlos D. da Gama, Charles R. Nelson

Griffith’s theory of brittle fracture, as modified by McClintock and Walsh to fit rock behavior in cases of failure by compression, has been successfully applied in various fields of rock mechanics. Extension of the Griffith's criterion to rock blasting problems may also be more representative of rock behavior than the simple consideration of a criterion of failure based on the dynamic tensile strength of the material. If consideration is given to pre-existing cracks within rock structure, occurring not only because of the discontinuous properties of rocks, but also as a result of drilling operations that normally precede blasting, those cracks can be propagated under the action of the dynamic stresses (radial and tangential) induced by the passage of the wave emitted by the explosion. Conditions for initiation and propagation of pre-existing cracks are deduced in terms of rock properties and explosives performance. Influence of the different variables governing the phenomenon is discussed after considering an actual example. Results seem to be well correlated with experimental evidence of radial cracking observed in blasting with high explosives acting within hard rock.

Jan 1, 1971

By Richard D. Snouffer

Prime topics of conversation these days are the new concepts of rail haulage for bulk items such as iron ore, potash and coal. We have heard such ideas as the "integral train" and the "unit train" discussed frequently during the past two years at various AIME meetings, and progress reports have kept up a steady appearance in the technical press and in local newspapers. While no railroad has a complete "unit train" in service at this moment, one has 50 fast-discharge cars under construction and the Pennsylvania Railroad has experimented with radio-controlled motive power distributed at intervals throughout the train. To a great extent, however, the promise for greater efficiency and lower costs held out to industry by these new haulage methods is dependent not on greater speed or larger cars or more dedicated equipment alone but, rather, on the utilization of modern practices in the loading and unloading of rail cars. It is the purpose here to examine these two key steps and the up-to-date procedures and equipment they entail.

Jan 7, 1963

By F. B. Richards

For the last five years the furnace-men drawing their oresupply from the Lake Superior districts have had to solve the problem of using the very fine Mesabi ores as part of their oremixture. It is not my purpope to dwell on the early experiences and the progressive development in the use of these ores up to this time, but to lay before the members of the Institute one prominent feature concerning them, namely, the frequent and sometimes very disastrous slips (?) or explosions (?) occurring at furnaces where these ores are used. The Transactions of the Institute contain very little on this subject. Mr. F. E. Bachman, in his discussion of Mr. 0. 0. Laudig's paper (Trans., xxvi., 1061), advances a theory as to the cause of these occurrences; but this is the only reference to the subject in the Transactions up to this time, so far as I can recall. Probably all the furnace-men running the harddriven coke-furnaces in the central West have had more or less experience with this trouble; and I believe the majority of

Jan 1, 1899

By R. R. Nash, W. F. Sheely

Experiments were conducted on magnesium monocrystals in order to collect quantitative information on the mechanisms which limit the rate of basal slip. Using critical shear stress and creep data, activation energies for creep at low aid at high temperatures were derived. The activation energy at low temperatures is the same as that for jog formation and the activation energy at high temperatures agrees with that for climb. COTTRELL has suggested that at low temperatures, the expansion of dislocation loops under stresses near the yield strength is limited by the rate at____ which the expanding loops can cut the "forest" of dislocations passing through the glide planes.' On the basis of this mechanism, seeger2 has derived expressions for low-temperature creep and for the relation of flow stress of single crystals to temperature. In the work reported here, the authors have performed experiments designed to obtain quantitative data on the physical properties of the dislocation intersection mechanisms operating during basal slip in pure magnesium monocrystals. Above a critical temperature, dislocations thread-

Jan 1, 1961

By G. S. Brooks

(New York Meeting, February, 1913.) THE tendency of the oxides of such metals as aluminum, zinc, chromium, and calcium to form compounds at high temperatures with iron oxide is well established by past investigation. Data of this reaction, as developed in laboratory research, have been contributed by Burleigh, Hofman, and Wells, in America, and by many others abroad. A partial bibliography of the subject is appended. From these authorities we learn that the ferric oxide here has the function of an acid, giving in the case of ZnO a zinc ferrite, with a normal composition of ZnOFe2O3. This formation of zinc ferrite particularly affects the success of such processes as leaching or magnetic separation, and thus becomes practically important to the metallurgist. But the meager existing data do not entirely agree; and quantitative results from muffle-practice are conspicuously absent. Furthermore, it being of some general importance to the zinc smelter in both roasting and reduction, the following few notes of operations on a commercial scale are contributed

Jan 5, 1913

By K. U. Snowden, J. N. Greenwood

CRACKS which form in lead exposed to fluctuating stress frequently follow a rectangular pattern. It is well known that under ordinary atmospheric conditions these cracks are intercrystalline. On the other hand after fabrication the crystal grains in lead are in general irregular polygons. The observed facts appear to be mutually contradictory. Re-examination of some lead failures has confirmed that the rectangular cracks are intercrystal- line. It follows therefore that under fluctuating stress some of the grains lose their irregular outlines and become approximately regular polygons of cubic type. G. R. Gohn and W. C. Ellis* suggest that this is due to recrystallization during the life of the part, in such a way that the new grain boundaries are aligned at 45 deg to the longitudinal strain prior to the formation of the fatigue crack. Experiments at Baillieu Laboratory—Some recent experiments carried out in the Baillieu Laboratory in conjunction with the Broken Hill Associated Smelters have thrown some light on this transition. A test piece of pure lead was polished chemically

Jan 1, 1959

By M. E. Volin, F. H. Erbisch, G. M. Wenberg

Bacterial leaching of copper and uranium is practiced under acidic conditions in environments furnishing sulfur and iron. However, many mineral deposits do not have these conditions; the chalcocite and native copper deposits in Michigan's Upper Peninsula are examples. Species of bacteria and fungi isolated previously from samples taken at the White Pine Copper Co. tailings pond and mine, were screened for solubilization of copper from chalcocite ore and flotation concentrate and from native copper jig concentrate. Certain Penicillium species solubilized significant amounts of copper under neutral to slightly acidic conditions in a carbon and nitrogen-enriched medium. Leaching apparently was accomplished by release of metabolites which chelated with the copper. The copper yield was highly dependent upon the medium composition and the concentration of copper in the source material. The standardized procedures which were developed in an attempt to maximize copper yield in leaching times of three to five days are described. This preliminary research indicates a biological leaching process for copper which is different from those in use, but whether it can be applied economically remains to be determined.

Jan 1, 1972

By John Hower, Frank J. Markewicz, William Lodding

Greensand, greensand marl, and green earth are names given to sediments rich in the bluish green to greenish black mineral known as glauconite by the mineralogist. The word glauconite is from the Greek word glaukos, meaning bluish green. The term "greensand" as a rock name for a glauconite-bearing sediment is more appropriate than "greensand marl," a term that has been doggedly perpetuated in the literature. Because of its potash and phosphate content, greensand was dug and marketed as a fertilizer and soil conditioner for more than 100 years. The advent of prepared fertilizers with adjustable nutrient ratios led to the decline of greensand for agricultural application. The material has since been recognized for use in water treatment. Unfortunately, in spite of large reserves and worldwide distribution, the mineral has not been utilized to any significant commercial extent because no major application has been found for a substance with its chemical composition and properties. This lack is probably due to a paucity of research on its potential commercial application. Extraction of potash received considerable attention during and just after World War I. Because of relatively high extraction costs and generally low potash content (up to 8% ), glauconite lost its appeal as a source of this commodity. Historical Background Greensand was used as a fertilizer in New Jersey in the latter part of the 1700s. During the early 1800s its use became more common; applications of up to 100 tons per acre were sometimes made, although recommendations for agricultural use suggested 20 to 50 tons per acre (Tedrow, 1957). Many crops, especially the forage type, were said to improve with greensand application; however, because of, slow release of potash, large quantities were required. Certain greensands that contain sulfur and sulfide minerals are harmful to plant growth, and these were classified as "poison," "burning," or "black marls." The availability of higher-grade potash salts from other mineral sources, and the manufacture of prepared fertilizers, displaced the agricultural use of greensand during the later 1800s. During the mid-1800s the domestic greensand industry, centered in a small section of the eastern United States, grossed more than $500,000 per year. Toward the end of the century, annual production had dwindled to less than $100,000. By 1910 there were only six or eight greensand producers, grossing less than $5000 (Tyler, 1934). There was a small revival in the industry during World War I because of the curtailment of foreign potash, especially from Germany. During the later 1940s and early 1950s greensand was again recommended as a food nutrient for plants and farm crops. Agronomic studies discussed its potential as a soil additive that gradually releases potash and many trace-element nutrients essential for plant growth (Tedrow, 1957). Greensand was sold with the idea that it would condition soil and absorb and hold water while its base-exchange properties would release trace elements. For a short time glauconite was utilized in certain parts of New Jersey as a binding additive in the brick industry, and in the 1800s for making green glass (Cook, 1868). In the early 1900s the base-exchange property of glauconite was recognized for water treatment, and the mineral gained acceptance as a water softener. Mansfield (1922) does not mention base-exchange; however, the base ex-

Jan 1, 1983

By H. W. Schreiber, H. R. Babitzke, R. E. Rodriquez, Patterson J. A., C. D. Masters, J. J. Schanz, R. B. McCammon, E. A. Noble, P. M. Krishna

A five-year effort by the ASTM subcommittee E10.14 on uranium resource evaluation has culminated in the approval of E901-82, Classification System for Uranium Resources (ASTM Standard E901-82, April 1983). The standard classification was prepared with participation of representatives from the US Department of Energy, the US Department of Interior's Geological Survey and Bureau Mines, utilities, and consultants. The classification a resource is based on level of knowledge and the economic producibility of the resource at a given time. Alphanumeric identifiers are used rather than words to avoid confusion with existing terms, definitions, and classifications. An example demonstrates the dynamic nature of the process of classification and attests to the necessity of addressing both the aggregate needs of broad-scale resource planning and the specific needs of individual property evaluation. Problems that remain infixing the classification a given uranium resource include uncertainty in estimating the quantity of undiscovered resources and resolving differences that may exist in deciding when the drill-hole spacing is adequate to determine the tonnage and grade of discovered resources.

Jan 1, 1985

Since I have had the pleasure of watching the development of this process very closely, I feel that I ought to say a few words on the subject, although I cannot add much to what Mr. Roe has already said. I wish, however, to bear witness to the hard work, persistence and skill which have been exercised during the past two years, and which have so well deserved the success attained. Those of us who remember the history of the past efforts in this line, such as the rotary puddlers, in which also some of us had a part, can easily appreciate the problems involved, and may well be skeptical as to the outcome. Such, at least, was my frame of mind when the process first came under my notice. Now, after having seen every heat, but three, of the many made, it really seems to me that a process and plant for the mechanical puddling of iron has at last been developed which is practical, economical and successful. Of course I do not mean by this that either the process or the machines are developed to their highest point, technically or economically, but that, in my opinion, these goals are in plain view, and that the difficulties which remain are such as will be overcome by developing the skill of the operator through practice ;

Jan 1, 1903

By Kendall E. Born

Production of crude oil in Tennessee during 1943 was approximately 8200 bbl., slightly less than the 1942 production, Counties. Some half dozen wells in Clay, Fentress, and Pickett Counties, pumped intermittently, produced about 1000 barrels. Natural gas was marketed from wells in Morgan and Fentress Counties for consumption in the Sunbright and Jamestown areas, respectively. The Morgan County production was about I0,000,000 cu. ft. and approximately 8,000,000 cu. ft. was produced from the Jamestown gas field from six wells. The production of oil by counties is shown in Table I. Thirteen wells were spudded during the year; three were drilling on Dec. I, 1943. Of the nine completions, representing 10,488 ft. of hole, three were gas' wells of commercial size although only one of them has been placed on the line. The completions are listed in Table 2. The distribution of tests according to physiographic divisions is given in Table 3. Cumberland Pluteuz.-There were three completions in the northern part of

Jan 1, 1944

The following communication has just reached the Institute, from the office of the Provincial Geologist, Department of Lands,-Forests and Mines, Ontario, Canada: During the autumn of 1917 gold was discovered in unsurveyed territory south of Lake Abitibi in northeastern Ontario. This area lies about 70 miles almost directly east of the well known Porcupine area. During the coming summer, the Ontario Bureau of Mines is to make a geological survey of this new gold area. Following the custom of Ontario, this area is being divided into townships, 6 miles square. These townships have recently been given the following names in honor of men well known in the mining and geological world. In alphabetical order the names are as follows: Frecheville-Prof. Wm. Frecheville, Professor of Mining in the Royal School of Mines, London; Past President of the Institution of Mining and Metallurgy. Garrison-Mr. F. Lynwood Garrison, Mining Engineer, Philadelphia, Pa. Harker-Dr. Alfred Harker, F. R. S., immediate Past President of the Geological Society of London.

Jan 6, 1918

By Kendall E. Born

Production of crude oil in Tennessee during 1943 was approximately 8200 bbl., slightly less than the 1942 production, Counties. Some half dozen wells in Clay, Fentress, and Pickett Counties, pumped intermittently, produced about 1000 barrels. Natural gas was marketed from wells in Morgan and Fentress Counties for consumption in the Sunbright and Jamestown areas, respectively. The Morgan County production was about I0,000,000 cu. ft. and approximately 8,000,000 cu. ft. was produced from the Jamestown gas field from six wells. The production of oil by counties is shown in Table I. Thirteen wells were spudded during the year; three were drilling on Dec. I, 1943. Of the nine completions, representing 10,488 ft. of hole, three were gas' wells of commercial size although only one of them has been placed on the line. The completions are listed in Table 2. The distribution of tests according to physiographic divisions is given in Table 3. Cumberland Pluteuz.-There were three completions in the northern part of

Jan 1, 1944

ARSENIC and orpiment are two mineral substances of a similar kind, and they are by nature pure, without admixture of other species. In regard to their apparent qualities we shall say that their composition is scorched, well-purified earth; and because of a certain subtlety and easy digestion they penetrate very easily into fused metals, indeed they act in such a way that they corrupt and convert almost into another nature any metal with which they find themselves. Orpiment and arsenic act in almost the same way as do tin and mercury. With these the fraudulent alchemists blanch copper, brass, and even lead to the whiteness of silver. According to the physicians they are in fourth part hot and dry. They are also corrosive because of certain powers; indeed, they are a most powerful poison to the life of all things. Arsenic is found in white and citrine colors. Orpiment seems to be a separate thing, although both are formed in the same ore and both are in lamellae or scales. These lamellae or folds are thinner than paper, in fact

Jan 1, 1942