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By H. N. Mills

The glass industry is a major user of many industrial minerals in the manufacture of its product. It is the intent of this chapter to: (1) acquaint the reader with the glass industry by including a few production statistics, and then (2) cover the various aspects of the major raw materials used to make glass. Some of the items covered are: type of materials, their function in glass, their composition, cost, and the relative quantity used in glass vs. totals produced. In addition, a discussion of glass raw material specifications, some byproduct materials used in glassmaking, and comments on future prospects related to the environment, technology, and growth are included. The matter of glass compositions, properties, and batches is considered beyond the scope of this chapter which deals only with raw materials. For more details on the particular minerals and rocks, the reader is referred to the commodity chapters in this book.

Jan 1, 1975

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 Francis J. Dennis

Many factors govern the value of dredging-ground, and much capital can be wasted by the mistaken policy of contracting for the purchase of property arid the installation of machinery before a thorough examination has been made. To the uninitiated investor the presence of gold is generally the criterion, and very superficial evidence is necessary to satisfy him as to this point. he couuiclers the comprehensive report of a competent engineer as a wasteful extravagance, aild cannot understand why the engineer requires so much time and money to ascertain the information on which to base his conalusions, when the promoter can furnish him such pleaaing and satisfactory data with but little expenditure of time aud money. The uninitiated investor will often optimistically risk capital for purchase and equipment, and riot uiitil the veuture comes to grief does he learn that the condition8 are wholly unsuited for dredging. In many instances, a short preliminary examination by a competent engineer would have disclosed these facts. The mere presence of gold is by no means suficient; sonie of

Jan 1, 1912

The new, internationally-owned Savage River Mines iron ore mining, concentrating and pelletizing project, built and operated by Pickands Mather & Co. International, was dedicated March 6 at Port Latta, Tasmania, Australia. Construction of the $79 million project began in 1965 and involved an open pit mine and concentrating plant plus a complete town for about 350 employees at Savage River; a 53-mile pipeline to transport the concentrates; a pelletizing plant and shipping facilities at Port Latta, which is on Bass Strait separating Tasmania from the Australian mainland. The project has a rated capacity of 2.25 million Ltpy of high-grade magnetite pellets, which will be sold to five Japanese steel companies under 20-year contracts. The open pit mine is located in the central portion of the Savage River deposits. Mining equipment, capable of moving 10 million tpy of ore and overburden, consists of four 6-cu yd electric shovels and 12 50-ton trucks. The concentrating plant, with a design capacity of 5 million tpy of ore, will use magnetic separators to upgrade the ore, which averages 38% iron, to a concentrate averaging 67% iron.

Jan 4, 1968

By David L. Pentz

ABSTRACT A critical summary is given of the analytical procedures available to the engineer for the analysis of slope stability. The emphasis is on the various types of behaviour that have been measured in different rock types. A method of assessing the possibility of failure of simple three dimensional wedges is provided in an attempt to demonstrate how structural features can be included in a meaningful manner. An outline for theoretical design is provided that stresses the importance of carrying out a 'Back Analysis' of large and small instrumented failures so that realistic parameters of the rock mass forming the pit slopes can be obtained.

Jan 1, 1971

By Ronald L. Longwell

PROPERTY LOCATION Located in the Copper Creek area of the Galiuro Mountains, the Old Reliable is on ground first claimed for mineral value during the Civil War. The deposit was mined sporatically from 1880 to 1919 and again in 1953 and 1954, with a total of about 30,000 tons of ore removed. The ore body is a near vertical breccia pipe containing approximately 4,000,000 tons of 0.80% copper with mineralization occuring as chalcocite, chalcopyrite, malachite, chalcanthite, and chrysocolla. The host rocks are extrusive lavas of cretaceous age which were intruded and mineralized by Copper Creek Granodiorite, which is Laramide in age. The ore zone, which occurs on the toe of a ridge, is about 300 feet by 600 feet in plan, with the bulk of the deposit extending from the surface to a depth of 500 feet.

Jan 1, 1974

By Robert Longyear

IN, diamond-drill work, a true sample consists of all the material cut by the bit-both core and cuttings. As the recovery of this sample is the object of diamond drilling, the utmost care should be taken to secure it. Speed of drilling and low costs are of little value if an inaccurate sample is obtained. The engineer in charge must study his material and lay out the plan of sampling, and then see that the drill runner follows his instructions; for the runner may be more interested in obtaining a large footage than in developing accurate methods of sampling. FIG. 1.-CORE BOX. When the core has been removed from the core barrel, it should be placed in a core box in the exact order in which it is taken from the ground. This box, Fig. 1, is usually a shallow tray 4 or 5 ft. (1.2 or 1.5 m.) long, with partitions running lengthwise between which the core

Jan 12, 1921

Estimation of local recoveries is an important issue in a selective mining operation. Two techniques, probability kriging and multigaussian kriging, are applied to estimate local recoveries at Jerritt Canyon. The pros and cons of each method are discussed in light of the results. Both methods provide simple and satisfactory solutions to the problem of estimating local recoveries. Consequently, they can be useful tools to work with in a selective mining operation.

Jan 1, 1986

By W. E. C. Eustis

1st. The fine iron ore is mixed with a sufficient proportion of fine coking coal, and is coked in any of the ordinary methods for making coke. The effect of this is to convert the iron oxide into sponge in such a shape that the usual trouble of oxidation is avoided. 2d. The resulting mixture of coke and sponge is melted down ill an ordinary cupola, the coke furnishing more than sufficient fuel for that purpose. I may briefly point out here that in the first place the iron is sponged, and this sponge, as is well known, contains no phosphoras or silicon when the reduction takes place at a low temperature; and in the second place this sponge is melted down in a cupola in which there is no zone of reduction for phosphorus or silicon, and that con . sequently the resulting iron should be free from both of these impurities. 3d. The liquid sponge, now carburized, is run into an open-hearth furnace, where the requisite degree of hardness or softness is obtained by adding some of the fine ore, and the usual dose of ferromanganese, I have merely given above the rough outlines of the prows, bat it is my intention, as early as possible, to bring the process more fully before the Institute.

Jan 1, 1881

By J. K. Gerlach, E. D. Gock, S. K. Ghosh

Previous experience in leaching chalcopyrite with dilute sulfuric acid has generally resulted in rather poor extraction. However, the reaction rate of the leaching process can be significantly improved by an increase of the crystal lattice defects of the chalcopyrite. It was found that subjecting chalcopyrite to a milling action involving a strong impact, permits 99 percent of the copper to be extracted in a subsequent single leaching stage with at least stoichiometric quantities of sulfuric acid in the presence of oxygen at 100°C. Simultaneously, about 80 to 85 percent of the sulfide sulfur content is converted to elemental sulfur. The dependence of the reaction rate of chalcopyrite on the pretreatment, temperature, oxygen pressure and acid content will be discussed.

Jan 1, 1973

I am much pleased by your presentation of my article and flattered to the extent that the cover design refers to it. Incidentally, as between folks who like to work with words, refer to line 6, second full paragraph, page 773 (August Mining Engineering) Would "for" preceding technological have changed the percentages in lines two and three of the bold-face heading on page 770? The intent was coequality among three, (studies of mankind, of science, and of technological empirics). Thirty-three pct for "man" studies is a pretty big bite for engineering schoolmen; 50 pct they won't even examine, let alone nibble at. Arthur F. Taggart For those of you without a copy of the August issue handy, the sentence referred to read: The plea herein is to make the overall time allotment for studies of mankind coequal with those, for science and technological empirics.... Professor Taggart suggests that insertion of the word "for" would clarify the intent of coequality among three divisions of study: The plea herein is ... for studies of mankind coequal with those for science and (for) technological empirics. Editor.

Jan 1, 1952

By J. Ehner Thomas, M. D. Gould

Until four years ago the market price of oil securities moved directly and immediately with the general list. This point, was first developed by the senior author in 1924 while making a statistical study of the relative movement of oil securities and the general market. Plotting the monthly averages of 17 oils against 233 industrials disclosed the sur- prising relationship shown in Fig. 1. The traditional vagaries of the oil business, the wide fluctuations in current supply and resulting abrupt changes in crude prices nevertheless produced no movements in the market price of oil securities as a group, which departed notably from the movements of the general market. Obviously general business conditions did not always change when and as conditions in the oil industry changed; clearly the fluctuations of

Jan 1, 1929

Jan 1, 1917

By Douglas Ragland

Two subjects certain to incite interest among a few practicing engineers and almost all engineering educators are professional recognition and decline in engineering enrollments. It is not surprising that this interest on the part of the educators is universal; it is only regrettable that such an interest on the part of the practitioners is not more widespread. In fact, it is probably the hope of the profession that some of the more penetrating searches now being made into the nature of engineering will generate sufficient cause for perplexity that members of the profession will assume a significant degree of personal concern toward purely professional matters.

Jan 1, 1963

By D. H. Gieskieng

THE advent of curved jaw crusher wearing plates made an approach other than segmental layout analysis desirable for prediction of capacities. For some time it had been known that the drawing board capacities of crushers using these plates had to be considerably modified by complicated experience factors to achieve agreement with results. Because these apparent capacities could be readily increased severalfold by minor crushing chamber shape changes, it was necessary that the utmost precaution be taken in predicting capacities of jaw plates modified for nonchoking, special wear characteristics, or any other reason. To this end the laboratory and field tests outlined by the author in a previous paper' were made on Blake-type jaw crushers. The results of these tests were summarized in a simple first degree equation applicable to crushers using either straight or curved jaw plates. This equation first outlines the maximum capacity potential of a given crusher, then reduces this figure in accordance with installation circumstances by means of a realization factor.

Jan 11, 1951

WE the undersigned, being all persons of full age and citizens of the United States, and a majority residents of the State of New York, desiring to form a corporation pursuant to the provisions of the Membership Corporations Law for the purpose of incorporating, as provided in Section 5 of Article I. of said law, the existing unincorporated association known as American Institute of Mining Engineers, do hereby make, acknowledge and file this Certificate for that purpose, and do Certify as follows: I. That the American Institute of Mining Engineers is an unincorporated association organized and existing with the object of promoting the arts and sciences connected with the economic production of the useful minerals and metals and the welfare of those employed in these industries by means of meetings for social intercourse and the reading and discussion of professional papers, and to circulate by means of publications among its members and associates the information thus obtained. II. That the persons duly appointed or designated to manage the affairs of said association are designated by the rules thereof Members of its Council; that the under-signed are all members of said Council as the same was constituted on the 29th day of December, 1904.

Jan 1, 1934

By C. M. Fellman

AVAILABLE data for the first nine months of the Year indicate that accident occurrence in metal mining was well on its way to an all-time low for 1939. However, the relatively rapid pickup in mining production in the fall will be likely to boost both accident occurrence and also accident rates. Results of the National Safety Competition for 1938, the fourteenth of its kind conducted by the U. S. Bureau of Mines, were published in August, 1939. W. W. Adams, statistician of the bureau, states that "with 345 mines and quarries competing, more than in any previous year except 1931, the contest revealed low accident rates at many of the enrolled plants and, which is even more remarkable, it revealed 113 mines and quarries at which no lost- time accidents occurred during the con- test year." The National Safety Competition provides a means whereby mines and quarries may engage in active competition to stimulate their safety programs. Companies in the contest can compare their records with those of similar plants operating elsewhere and thereby determine to what extent their safety programs are successful. The Joseph A. Holmes Safety Association gave over 150 awards for safety performance in the mineral industries in 1939 and a remarkable phase of these awards was the considerable number given to individual miners who had worked fifty or more years without sustaining a lost-time accident.

Jan 1, 1940

Masjid-i-Su1aiman.—There have been no new developments in the Masjid-i-Sulaiman oil fields during the year 1938. In spite of the age of this field, the fall in dome pressure shows no appreciable variation from the low rate of about 0.3 lb. per sq. in. per million tons net production. Drilling has been limited to deepening old wells and to new wells required for maintenance of production and general reservoir control. The rate of offtake has been reduced over the past few years, partly because of depletion of the oil column, and it is expected that future offtake from the Masjid-i-Sulaiman field will be stabilized for some years at around the present figure of 3,000,000 tons per annum. Haft Ke1.—An exploratory well to test deeper formations in the Haft Kel field has proved the existence of productive conditions in the Eocene, which underlies the Asmari limestone (the main producing horizon). Drilling to the northwest in the white-oil springs area has revealed the presence of a separate structure with productive potentialities. One well with a satisfactory production rate has been completed. Offtake from the Haft Kel field has steadily increased since it first came on to production in 1929. Naft-i-Shah.—Production from this field has continued to supply market requirements in northwest Iran. The policy of returning surplus products to the reservoir, which was adopted at the beginning of 1936, has been continued.

Jan 1, 1939

By P. A. Albert

THE to a transformation has been investigated by Newkirk1 in sponge titanium alloys which had been relatively slow-cooled so that several grains formed in a former grain. For a nucleated from , Newkirk assumed the following relationships and found them consistent with his experimental results: (00.1)a (110)Pll.01. II [111] Liu and Margolin,' in their investigation, found that the habit planes of martensitic in titanium consisted of planes of the families (3341, and (3441,. Using Newkirk's orientation relationship, the (3341 habit plane is found to correspond to the (1450) plane of a.

Jan 1, 1954

By R. O. Burt

The economics of recovering slimes by gravity concentration, except in a few highly specialized cases, was hampered by the lack of suit- able high capacity equipment. However, in the last decade increasing cost of power and reagents, coupled with the development of high capacity units, has led to a reappraisal of the benefits of slime gravity concentration. This paper seeks to analyze the merits of gravity concentration, and the constraints placed upon it by the laws of motion. It traces the recent developments of unit processes, and their application to a wide range of minerals. The economics of gravity concentration are also discussed.

Jan 1, 1980