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By Robert H. Richards

VERY little has been published recently on this subject in the mining journals or proceedings of societies. The attention of experts has been diverted perhaps by the demands for pan amalgamation of refractory ores. Yet free milling ores occur in many localities, and it may be interesting to have on record some data as to details of running a small test-mill, especially as details of results do not seem to be accessible to students and investigators. Küstel, in 1863, under battery amalgamation, dismisses the subject by stating that "amalgamation on copper-plated platforms, troughs, and other copper fixings" is " very imperfect, and mostly abandoned." J. Arthur Phillips says, in 1867, under placer mining : A well-amalgamated copper plate is considered as effective for

Jan 1, 1880

By AIME AIME

TECHNICAL achievement in mining will be rewarded at the forthcoming Annual Meeting of the Institute when the William Lawrence Saunders Gold Medal will be presented to Herman C. Bellinger. Mr, Bellinger was unanimously selected on the first ballot of the Medal Committee. Mr. Bellinger has had notable technical success as vice-president in charge of operations for the Chile Exploration Co., a position he has held since 1920.

Jan 1, 1941

By E. P. Pfleider, O. Rellensmann

In the May 1959 issue of [=] the authors reported on the gyrotheodolite as used for determining azimuths in surface and underground work. Further research has led to the development of a new type of gyro instrument, the band-suspended gyro attachment, which is essentially an upset gyro attached to the top of a theodolite. The new gyro attachment is light enough to be mounted on any angle-measuring instrument if the design of the telescope standard permits. Gyrotheodolite units have been used to transfer meridian lines underground in the Coeur d'Alene mining district, although they have not been used extensively in the U.S. In other parts of the world, however, they have been adopted as the standard surveying instrument by mining engineers.

Jan 3, 1968

By David W. Kennedy, Stephen P. Harrison

In the past few years, a new system has been developed for ventilating longwall panels in some gassy coal mines in the Northern West Virginia area. This system utilizes a five or six foot diameter air shaft to ventilate a group of three or more longwall panels dependent on conditions. This shaft exhausts all the air needed to, ventilate the active longwall and adjacent gob areas. By law, this bleeder fan can handle double the maximum methane concentration allowed in a normal return air course. As a result, the methane that must be diluted by the primary ventilation circuits is reduced. This new ventilation system was first conceived by mine management as a means of coping with a sudden shift in production mode that occurred a few years ago. Formerly, production often consisted of room and pillar mining with continuous miners. The high methane liberation rate was handled by driving entries around a large block of coal prior to mining. This isolated the future mining area from the adjacent coal seam and allowed a major portion of the trapped in situ methane to bleed off. Also, these bleeders served to exhaust return air from the mining area. Once the bleeders were established, productive mining could start. When the decision was made to shift production mode from continuous miners to longwall mining, some of the bleeders did not encompass large enough unmined areas under the old ventilation system to initiate longwall production. Also, many other established continuous miner section bleeders were either improperly positioned or too restricted for longwall ventilation. Unfortunately, standard bleeder development can take up to two years' time. In order to eliminate the old style bleeder system and maintain or increase the margin of safety for ventilation, the bleeder shaft system was conceived. With this system, the only entries developed are those necessary for the longwall, significantly reducing the production delay. In this area, the Pittsburgh #8 coal seam dips to the northwest. As a result of this dip, the bleeder shaft is constructed in the northernmost set of tailgate entries. In this manner, groundwater accumulations can be pumped to the surface and bleeder entries kept dry. During the initial longwall entry development, the bleeder fan can be used to ventilate entries adjacent to virgin coal where significant methane liberation often occurs. Once longwall production starts, the bleeder shaft exhausts the entire air quantity necessary to safely ventilate the longwall. As the bleeder entries deteriorate, the air quantity and pressure characteristics must be increased. The extreme flexibility of the centrifugal fan used at the surface allows the air quantity and pressure to be adjusted without stopping the fan. This improves safety by decreasing the possibility of a methane buildup resulting from the fan being out of service. The bleeder shaft system of ventilation, developed by mine management in Northern West Virginia, can provide a safe means for effectively ventilating longwall panels in excessively gassy mines. This system should be considered where mining conditions are comparable.

Jan 1, 1982

By Frederick Laist

I AM APPRECIATIVE of the honor you have done me in electing me to membership in your Society. I value the contacts with men of imagination and ideals which this implies. I am grateful for the recognition of such small contributions as I may have made, or helped to make, to the vast fund of scientific and engineering knowledge. We like to think, as we grow older, that our lives have not been purely parasitical, and that through our efforts some forward step, however small, has been taken toward improving conditions under which we live and do our work. In these days of industrial depression, we hear much criticism of our "machine age." Modern engineering, mass production, the complexity of our lives, all come in for some share of blame. The farmer is said to have been spoiled by the tractor and the gang plow, the factory worker has become a slave of the assembly conveyor, the scientific worker is no longer free but has sacrificed much of his individuality to the research organization of which he is a part. We wonder whether our work as engineers has been worth while and whether our striving after more efficient ways of doing things has been a curse to mankind rather than the boon we thought we were conferring.

Jan 1, 1932

By William J. Potter, Roger N. Pyle

Introduction The primary ingredient for survival of mining companies during a recessionary period is to be innovative and resourceful in the structuring and financing of operations. Over the past decade, many mining companies have had to retrench and restructure their operations and to redeploy their assets just to survive. During the same period, traditional sources of financing for mining companies -- commercial banks, subsidized export credit loans and long term straight debt financing in the public markets -- became less available and more expensive. Meanwhile, new markets and new financing instruments provided new alternatives for mining companies. Those companies which exploited these alternatives greatly enhanced their capacity for survival and even for profitability. This article considers the strategies adopted by some companies to adapt to changes in this recessionary environment; the inadequacy of traditional sources of financing; certain of the new financing instruments, structures and markets which have become available; and how several mining companies have utilized these new instruments, structures and financial markets to improve their competitive positions. THE IMPACT OF RECESSION ON MINING COMPANIES AND TRADITIONAL FINANCING SOURCES In its 1983 year-end article "The New Economic Order" Mining Journal characterized many of the large private sector mining companies with operations in the industrialized countries as being "gripped between the jaws of high working costs and stagnating metal commodity prices." The article went on to characterize the Canadian mining industry in particular as being "in the difficult position of having to seek to sell the bulk of its output in a world market characterized by over-capacity, where production costs were determined by internal political and economic factors while prices were set by external competitive forces of supply and demand." Miners of a wide range of commodities in the industrialized countries have come to realize that their domestic mineral resources are in many cases no longer competitive with global sources of supply. To compete and survive they would have to rely on their technical and financial expertise in mineral exploration and development and in mining and processing. Strategies For Survival Global competition has compelled management in the extractive industries to improve their worldwide cost position. This is the only means whereby a mining company can differentiate its product and attain a substantial competitive advantage. During the past decade, for example, ASARCO Inc. and Inco Ltd. chopped their payrolls, postponed expansion plans and otherwise retrenched. ASARCO reduced its capital expenditures and cash requirements for operations in 1984 to a level almost equal to its internally generated cash. The company's finances were also strengthened by increasing total lines of credit from outside sources, by selling common stock, and by reducing annual pension funding through a change in actuarial assumptions. Other companies returned to their traditional organizational structure where they had a demonstrated competitive strength. Consolidated Gold Fields, for instance, resumed its operation as a mining finance house. Its capital investment programs are now devoted solely to resource development. In mid-1984, at a time of firming zinc prices, Union Miniere S.A. used the opportunity to integrate its smelting capacity and to direct investment to certain subsidiaries at the expense of less viable operations. Smaller corporations realized that it was not enough just to be the low-cost producer. For example, Drummond Coal Company in Alabama, which dominates its regional market due to its low-costs, has also developed a world-wide trading capability and has placed incremental tonnage from its own mines as well as brokered coal produced by others, thereby minimizing capital risk. In Canada, Campbell Resources has exploited difficult times by acquiring assets cheaply. In the process it improved its capacity to withstand cyclical economic swings by diversifying from solely a copper and gold producer to a company based upon asbestos, coal, copper, gold and natural gas.

Jan 1, 1985

"The building stone industry of Utah has developed slowly on account of the limited market offered. The state has large and varied deposits of granite, limestones, marble and onyx.Three cement companies manufacture Portland cement in the Salt Lake valley. Brick clay, fire clay and clay for sewer pipe is found in the vicinity of Salt Lake City and Ogden.Large deposits of gypsum have been found in several localities in Utah. The gypsum deposit near Nephi has been developed to be one of the most important plaster producers in the western country. This gypsum occurs in large quantities and is exceptionally pure.Oil and Oil ShaleVast deposits of rich oil shale occur in the Green River formation of the Tertiary rocks in the Uintah Basin, northeastern Utah. It is estimated by the United States Geological Survey that the basin contains at least 92,159,000,000 tons of shale which will yield as much as 15 gallons of oil to the ton when distilled. These shale deposits indicate that ultimately Utah will be one of the leading shale oil producing states of the country. Some development work and considerable experimental work has been done, but overproduction of petroleum and general low prices afforded little incentive to the oil-shale operator, consequently no commercial production has yet been established in Utah."

Jan 1, 1925

By Freeman Bishop

Quietly picking his way through the thorny thicket of conservation issues is William E. Ruckelshaus, director of the Environmental Protection Agency in which President Nixon gathered the various anti- pollution units from the Interior, Commerce. Agriculture and Health. Education and Welfare departments. Mr. Ruckelshaus. EPA's first administrator, moved over from being Assistant Attorney General in charge of the civil division at Justice to this new post. Essentially, EPA is charged with administering swiftly proliferating antipollution programs. This means policing industry cities, farms and everything else. Ruckelshaus has been quietly fitting together the various pieces of this new agency, pulling then1 out of other Federal departments. Some 5800 employees are involved. The budget in 1971 for these segments will total about $1.5 billion.

Jan 1, 1971

By S. H. Chauvenet

The binding of the boshes and inwalls of blast furnaces has always been an expensive piece of work. When the old stone stack was replaced by the iron shell, the brickwork was kept at a thickness of five feet or more. These five-foot walls were still too thick, and the practice now is to have as thin walls as possible and to have a free circulation of air about the brickwork of the furnace. The " basket," or lattice-work biuding, accomplishes this object, but it is expensive, m to first cost, and, if any change in the diameter of a furnace has to be made, it necessitates an alteration of the binding or of the thickness of the walls.

Jan 1, 1882

By William E. Bruce

In recent investigation of drilling processes, the U.S. Bureau of Mines measured the operating characteristics of two percussive drills. Basically, this entailed measuring maximum piston velocities while drilling. The maximum piston velocity is not necessarily the same as the striking velocity. The latter is usually somewhat lower1 because most commonly used drills provide an air cushion which slows the piston just before it comes in contact with the drill rod. Penetration rates for the two drills were determined in nine rock types, and the physical properties of the same nine rocks were measured and tabulated. Then the penetration rates were plotted against the individual properties to determine the general relationships on which methods for predicting drilling rates could be based.2

Jan 1, 1970

WM. A. COWAN, Brooklyn, N. Y. (written discussion*). -This is evidently an excellent continuation of the work described in the article "An Investigation of Fusible Tin Boiler Plugs" by Messrs. Burgess and Merica.1 The present paper gives information of much value in con-nection with the manufacture and inspection of fusible boiler plugs, and the investigation of the cooling curves of tin with various other metals close to the tin side of the diagram is very interesting. These curves corroborate in all cases, except that of antimony, the diagrams given by other investigators. However, only the liquidus curves of the thermal equilibrium diagrams are given, except for copper-tin alloys where one branch only of the solidus (representing the freezing, of the eutectic)

Jan 11, 1919

By George Holderer

THE relation between man-hours of labor and production may be correlated for any industry, and already it has been widely used in piece-work studies. It is not in general use as yet for recording labor efficiency of an enterprise or an industry. An exception to this is the Cement Institute, which tabulates the man-hours used in each operation and FIG. 1.-LABOR PRODUCTIVITY IN COPPER MINING. thus gets the total man-hours per barrel of cement. The writer knows of one steel company that keeps a complete record of man-hours for every operation from mining the ore to finishing the product. No doubt many others find the information useful, and such a study could be of value to the mineral industries.

Jan 1, 1935

By Kenneth L. Ancell

This paper traces the history and performance of a coal degasification project in the Black Warrior Basin of Central Alabama. The primary coal beds being degasified are the Mary Lee and Blue Creek. The area being developed for gas production is also scheduled for underground mining in two to seven years. The paper discusses the early data collection and evaluation. The coals are extremely gassy with some measurements in excess of 500 SCF/ton. Five experimental wells were drilled and produced. Geologic heterogeneities were encountered which affect the performance of the project. Drilling and completion practices together with well design considerations compatible with under- ground mining are discussed. Finally, the gas gathering and sales system together with the early production history is illustrated.

Jan 1, 1982

The primary purpose of the Institute is to advance the technologic and engineering arts embraced by it through interchange of knowledge This can best be done by the presentation and discussion of technical papers by its members Short practical papers are especially welcome An author should always satisfy himself that his material is of a quality that will be a credit to him and to the Institute The preparation of a good paper frequently leads to a reorientation of the author's thoughts, and publication contributes much to the professional standing of the author Members are urged to submit papers presenting the results of their work Attention to the following suggestions will greatly further the prompt and efficient handling of manuscripts

Jan 1, 1952

By R. W. Raymond

THE important question of the metallurgical value of the coals of the Rocky Mountains and the Pacific Coast is to be settled, of course, by practical experiment. Meanwhile; as I have had occasion to point out, the proximate analyses of these coals throws little light upon it, and is, indeed, likely to mislead the metallurgist, if he compares it with the results of similar analyses upon bituminous and semi-bituminous coals. With the view of showing how large a proportion of the material usually classed as." volatile matters " consists of combined water, or oxygen and hydrogen presumably in chemical combination, I have collected a number of ultimate analyses from various sources, in the following tables. The numbered analyses in the first table are as follows

Jan 1, 1874

By Sam F. Harrison

The National Board of Boiler and Pressure Vessel Inspectors again sends out this recommendation: If you have an air compressor that is mounted directly on the air tank, get it off. Characteristically, small- to intermediate-sized air receivers are thin-walled vessels, and as such are prone to failure when subjected to external loading. Many of these vessels, if not a great majority, are bought by a distributor of air compressor systems, who provides the compressor, motor, switchgear and other accoutrements-all of which are very frequently mounted on a base which is then welded to the shell of the receiver. These welds at the points of attachment transmit external loading to the tank in the form of weight and vibration, frequently resulting in stress-induced cracks.

Jan 3, 1978

By Charles L. Elliot

Worldwide manpower utilization reached a new high at 10,482 professional man-months and expenditures increased to $19.9 million for mining geophysical activity during 1965. This is up from 9323 man-months and $14.5 million in 1964. Worldwide geophysical activity measured in percent distribution of the total manpower utilization and expenditures is presented in the accompanying Figs. 1 and 2. In terms of the total manpower utilization, ground surveys accounted for 61%, airborne surveys 18%, and mining geophysical research activity 21%. For expenditures, the breakdown was ground surveys, 49%; airborne surveys, 3901o; and research, 12%. Industry was responsible in general for 74% of the manpower utilization and 80% of the expenditures. Manpower costs in 1965 averaged $1900 per professional man-month.

Jan 11, 1966

The primary purpose of the Institute is to advance the technologic and engineering arts embraced by it through inter- change of knowledge. This can best be done by the presentation and discussion of technical papers by its members. Short practical papers are especially welcome. An author should always satisfy himself that his material is of a quality that will be a credit to him and to the Institute. The preparation of a good paper frequently leads to a reorientation of the author's thoughts, and publication contributes much to the professional standing of the author. Members are urged to submit papers presenting the results of their work. Attention to the following suggestions will greatly further the prompt and efficient handling of manuscripts.

Jan 1, 1946

By Sir Robert Hadfield

I am asked to contribute a few words to "The Book of British and American Friendship." This book of the two countries ought never to have been closed. It was a colossal mistake on the part of certain of our statesmen in the past which led to the severing of the interests of the two countries which, by the greatest of all bonds-Nature-were meant to be one. However, that is past, and a new book is opened, one full of promise for the world's future. I should imagine that outside the Kaiser-Junker classes, even the Hun himself would prefer to be under Anglo-Saxon laws and customs rather than his own. At any rate, judging from the number of Huns who have

Jan 8, 1918

By Gary B. Williamson, Barton K. Cross

Digital simulation is a modern analysis tool which allows the mine operator to evaluate the result of making a decision without actually changing the organization or buying the equipment. The purpose of this paper is to demonstrate the use of digital simulation in evaluating a decision of whether or not to introduce dispatching in an open pit mine. The analysis shows that appreciable savings can be realized by dispatching. In certain cases, an operator can reduce the number of trucks required to move a specified tonnage. A second analysis evaluates the alternatives of using one large shovel or two smaller units. In this case, the operating cost of the haulage equipment necessary to support the shovels turns out to be the critical factor in this decision.

Jan 1, 1969