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Succession of Minerals and Temperatures of Formation in Ore Deposits of Magmatic Affiliations BY WALDEMAR LINDGREN (Tech Pub 713 10,000 words ) The paper presents data accepted by many geochemists and geologists regarding the succession of minerals and the temperatures of formation in ore deposits affiliated with igneous rocks It also presents the individual views of the author on the composition of the solutions that were active and on the mode of deposition He does not regard these views as speculations or hypotheses but as forming a well motivated and con¬sistent theory It is not certain, however, that all investigators will subscribe to them The mining engineer may not always be interested in the field of stability and tempera¬ture of origin in the mineralogy of ore deposits, but he certainly is interested in the succession of minerals because this has a definite bearing on the understanding of the ores and on the best processes of extraction The author, therefore, summarizes in plain language the principal features of succession as shown in metallic ores

Jan 1, 1937

By J. Donald Graham, John G. Kuhn

The goal of any development drilling program is the drilling of the exact number of holes necessary to adequately determine grade and dimensions of an ore body, no more and no less. Any technique which eliminates unnecessary drilling costs produces beneficial results, both to the company and to the person who can claim the savings. The method for controlling development drilling programs to be described was developed during the latter part of a major development drilling project at the Christmas mine of Inspiration Consolidated Copper Co. in Gila County, Arizona. It was used to test the need for drilling individual holes but could be expanded to control an entire project. Application of this method involves an evaluation of geological conditions present and a good bit of common sense. Projects involving large disseminated, rather homogeneous ore bodies of the porphyry-copper type would be the most likely candidates for application of the technique. Discontinuous ore bodies would not be amenable. The method is based on the measurement of the linear correlation between the spatial distribution of two sets

Jan 1, 1973

By Yasuo Omori

Stabilized blast furnace operation at high production rates and reduced coke consumption requires control of the gaseous distribution within the furnace. This can be achieved only by an increased use of agglomerates in the furnace burden, and control of the radial distribution of agglomerates and that of coke in the blast furnace. Dissection surveys of commercial blast furnaces recently conducted by several steel plants in Japan gave much valuable knowledge on the behavior of agglomerates within the blast furnace, specifically in regard to the softening-melting zone. The authors analyzed these survey results in conjunction with laboratory studies on the behavior of agglomerates, then proposed appropriate test methods to determine high temperature behavior. A reducibility test at temperatures over 1100°C, a test for softening and melting under load up to 1400°C, and a test for melt-down characteristics were developed to evaluate behavior of agglomerates in the softening-melting zone of the blast furnace. The high quality of self-fluxing sinter, as compared with pellets, was verified by means of these test methods. The test conditions of the respective test methods were examined in detail.

Jan 1, 1977

By R. F. Campell, W. L. Jensen

IT is not uncommon for martensitic high carbon steels having a coarse austenite grain size to exhibit microcracks when polished and etched and examined with a microscope, as described by Davenport, Roff, and Bain.' Whether such cracks exist before etching or are the result of acid attack during etching has been debated from time to time. Fig. 1 illustrates the effect of electrolytic polishing, mechanical polishing and etching subsequent to each polish on microcracks produced by oil quenching from 1800°F a steel containing 1.14 pct C, 0.23 pct Mn, 0.33 pct Si, and 0.45 pct Mo. The austenite grain size was 3-4 on the ASTM scale. Grinding on lead laps followed by either electrolytic polishing with acetic anhydride-perchloric acid solution' or mechanical polishing with Linde "B" alumina on "microcloth" (sometimes referred to as Gamal cloth) revealed microcracks without conventional etching, as shown in Fig. la and b, respectively. These same fields, after subsequent etching with saturated picral, are shown in Fig. lc and d, and the cracks are seen to be typical microcracks; moreover, the cracks appear to be broader and longer than before etching. Although the microcracks were revealed by electrolytic polishing alone, the possibility of acid attack was present; however, the mechanical polish was accomplished without any intermediate etching to remove disturbed metal, hence this is regarded as definite evidence that microcracks are present before etching.

Jan 1, 1954

GEORGE F. BECKER Dr. George Ferdinand Becker, notice of- whose death appeared in the May Bulletin, was born in New York City Jan. 5, 1847, the son of Alexander Christian Becker, member of a Danish family, and Sarah Cary Tuckernian Becker of Boston. Dr. Becker was the last member of the group of distinguished geologists who, in 1879, were associated with Clarence King at the time of the organization of the United States Geological Survey. He was a leader in mining geology and geophysics, and for many years had been the chief of the Division of Chemical and Physical Research in the Geological Survey, and the investigations under his direction led to the establishment of the Geophysical Laboratory of the Carnegie Institution of Washington. Dr. Becker was a graduate of Harvard University and received the degree of Doctor of Philosophy at Heidelberg, and in 1871 passed the final examinations at the Royal School of Mines in Berlin. He was for four years an instructor of mining and metallurgy in the University of California, from which he went to the United States Geological Survey. In 1896 he examined the gold and diamond mines f South Africa and at the time of the Spanish-American War was detailed to serve as geologist on the staff of General Bell with the army in the Philippine Islands. He died at his hone in Washington, D. C., on Apr. 20'.1

Jan 6, 1919

By Walter Bonsack

THE CHAIRMAN.-This is the third and last session of the Institute of Metals Division's Symposium on Secondary Metals, and certainly the best of those that I have attended in the last few years. I would say that the increase in interest in secondary metals is quite noticeable by the steadily increasing attendance at these meetings. We have heard about the necessity of utilizing salvaged materials, but we still speak about them as low-grade, or down-graded materials. We still have the wrong perspective. We must willingly admit that these materials are valuable; we cannot go on using the choicest primary metals as morsels for our economic diet in a war of such unbelievable dimensions. This brings up the question-why are we so selective. The answer certainly is not that we know nothing else will do, but rather that we do not know what else will do. To be honest, we should admit our lack of knowledge concerning our complex alloys. Compared to the organic chemists, we metallurgists are very conservative, and the sooner we realize this and start to overcome it the better, because if we do not eliminate this difference, many customers of the metals business will go over to the plastics. If we take for example the development of aluminum alloys, you will see what I mean. From the binary aluminum alloys of 1920, we have progressed to ternary and quarternary alloys in the 1930's. We are only now beginning to use more complex alloys as we are forced to learn more about the effect of various elements on existing alloys. The effects of these elements should be studied now. They can be studied by two methods of approach. The usual method is to start from the base alloy and add various elements one by one in increasing amounts and study the resultant changes in properties. This is a tedious, long way. The other method which the smelters frequently use is to take the off-grade heats and study their characteristics. While the producer of primary alloys often has difficulties in alloying certain elements with the alloy under investigation, the smelter often finds them well alloyed in his raw materials and has no difficulties at all. Elements such as lead are difficult to alloy with aluminum and they tend to segregate severely. However, the amount which will remain alloyed in the metal is usually found in some "secondary" aluminum alloys. If one considers such concentration as the saturation, then by dilution with the same type of alloy, but free of such element, one can produce numerous intermediary alloys for investigation. In this fashion one is fairly certain to get uniformly spaced concentrations of the element under investigation. Similar cases probably exist with other metals. Nevertheless, the amount of work necessary to study all possible combinations is still tremendous. Necessity forces us now to utilize alloys which contain more elements than we are accustomed to. It is, therefore, necessary to study carefully the more complicated alloys. In secondary aluminum we are working and using the alloys which contain as many as 6 to 10 elements and we have learned over a period of several decades to balance

Jan 1, 1943

By Victor M. Braschi

The railroad history of Mexico began with the first presidential term of General Diaz. Concessions for the building of railroads had been granted in former years; indeed, an exclusive privilege was granted, August 22, 1837, to Francisco de Arrillaga for the construction of a railroad from Mexico to Vera Cruz, with a branch to Puebla, and other concessions were granted from then on at various periods; but the year 1877 was the real beginning of the regular and constant decelopment of the railways of Mexico. The programme laid out at that time by the new government, and responded to by the nation, was to develop its natural ele-

Jan 1, 1902

Jan 1, 1918

By Richard P. Rothwell

The ores treated by the Canada Consolidated Gold Mining Company at Deloro, Ontario, have been described in a paper read before the Institute in 1881. They are gold-bearing arsenical sulphurets of iron (mispickel), carrying the theoretical proportions of 42 per cent. of arsenic, 20 per cent. of sulphur, and the remainder iron. The gangue is quartz, calc spar, and some talcose, slaty rock, evidently resulting from the decomposition of the wall-rock, which on each side of the veins is syenitic granite. The treatment of the ore consists of: 1. Crushing. 2. Concentrating.

Jan 1, 1883

By T. A. Rickard

The lodes of Cripple Creek, Colo., partake of the composition of the geological formation which they traverse. The prevailing rocks are andesitic breccia, lying upon granite, and also bodies of phonolite, trachytic phonolite, nepheline-basalt, etc., penetrating both the granite and the breccia. At Kalgoorlie, in West Australia, the prevailing rock is schistose, and has not been certainly identified, though microscopic sections indicate the probability that it was originally an acid eruptive. The lodes are essentially bands, more highly schistose than the encasing rock, and impregnated to a notable degree with disseminated pyrites and secondary calcite. During 1899 Cripple Creek produced 425,590 tons of ore, having a gross value of $15,658,254; during the same period the output of Kalgoorlie was 467,048 tons, valued at $17,724,587. In chemical composition, the ores at Cripple Creek and Kalgoorlie, respectively, present differences equally interesting to the petrographer and the metallurgist. In both cases we have to deal with altered eruptives as the matrix of the ore; but the much older rock of Kalgoorlie has undergone more decompo-

Jan 1, 1901

A visitor to the Republic of South Africa might profitably make his first sightseeing objective the Voortrekker's Monument at the administrative capital, Pretoria. Here he will find memorialized in sculptured stone the epic of the migrations of Dutch colonists from the Cape in search of new pastures and to escape British rule. He will see depicted the battles with the Bantus who were coming south also in search of habitable land, the peace treaties with great chiefs and the rise of Afrikaaner leaders. An American will be struck by similarities in events with his own history as well as in clothes and in type of covered wagons of the colonists. Before the latter half of the 19th century, little that transpired in South Africa was of any great international moment. The country had not attracted a great many settlers (about 15,000 Europeans in 1800 compared to about 2 million in the American colonies in 1776). Although some gold was being mined the majority of population was engaged in trade or subsistence farming.

Jan 12, 1962

By C. O. Babcock

In this Bureau of Mines report, the authors present the results of laboratory tests on the burst proneness of coal. Many researchers have studied the violent breaking of large coal masses in underground mines, called bursts, but the causes remain uncertain. They have often assigned to geology and gas pressure the causative roles. The objective of this work is to show that stress can produce bursts in many coals if constraint is necessary for pillar survival and is suddenly lost. We tested coal samples from 15 mines, in 11 coal seams, in six states in the laboratory, and 13 were made to burst. These bursts were produced in several ways, but segmented steel platens were used in the tests reported. Two parameters analogous to the momentum and kinetic energy were used to rank the burst proneness of the coals tested. Tangential strains over the lower surface of the model coal pillar were measured to reveal a periodic slipping prior to the burst. High-speed motion pictures (350 frames per second) reveal the burst behavior in slow motion. We propose a modified Mohr-Coulomb stress-failure criterion to describe the burst behavior. When the horizontal constraint is suddenly lost with little change in the vertical stress, the Mohr stress circle increases in size dynamically, exceeding the static failure condition. When the inertia of the coal mass is overcome, a burst occurs. We conclude that most coals can be made to burst and that such bursts can be expected in mining at increasing depths.

Jan 1, 1984

By L. B. Lindemuth

TO those who are in a position to carry the thought to a conclusion, I would like to present a theory of the cause of blisters in ' galvanized sheets. Blisters that are caused from piping and shrinkage cavities will not be considered, because the reason for their formation is entirely obvious. Blisters that periodically occur, with no apparent system of location, number, size or grouping, and then disappear with no apparent change in manufacturing method, are the ones to which this theory would apply. Examination of blisters of the latter type has shown that they contain hydrogen gas at atmospheric pres-sure, and that occasionally traces of oxide or sulfide are found on the inner surface of the blisters. These two characteristics have led to the rather general idea that hydrogen gas generated in pickling, and that iron oxide supposed to be inherent in the ingot and causing weak spots, were, in some manner, responsible for the development of blisters in galvanizing. The theory which I wish to advance is that these blisters are caused by moisture that has penetrated the steel after the annealing operation. This moisture comes from the atmosphere, or from pickling or wash-ing, and when it is suddenly expanded into superheated steam in galvanizing, the increase in volume is so great that it cannot escape with sufficient rapidity through the small opening which it entered as moisture. The pressure so generated forces the sheet apart along those lines of lamination that may be found in practically all flat sections of steel rolled comparatively cold.

Jan 5, 1927

By Josef Westesson

No question in the metallurgical chemistry of the present day seems to be so difficult to agree upon as the determination of phosphorus in iron and steel. To my knowledge, there are at present at least three different methods in use in the iron laboratories of the United States, viz.: The citric acid method, the molybdate-magnesia method, and the direct molybdate method,—the last-named method having been lately adopted. Each of these methods has its advocates, who take every pains to prove its advantages, and the incorrectness of the others; and much has been written for the purpose of securing the use of a standard method—as yet, however, without any result. There is no doubt, or ought to be none, that each of these methods gives correct results, when it is carefully conducted and every precaution is taken. But it is not only correct results that we want nowa-days. The demand is great, also, for getting results in the shortest possible time. I think it has been sufficiently proved that the direct molybdate method, the weighing of the precipitate, answers well in both respects. Being a pupil of Prof. Eggertz, I have myself used his method for years until quite recently, as it is described by Mr. Troilius in our Transactions, vol. x., p. 166 (but with some slight modifications), and I can safely say that the results of this method agree well with those of the molybdate-magnesia method. I have, moreover, been checked, in a few instances, by some of the

Jan 1, 1885

By Carl J. Christensen

This paper presents the development of diamond coring of the Weber sand section in the Rangely Field, Colorado. The description and operation of the diamond-coring equipment is included as well as the economics and results obtained by its use. Diamond coring is compared with the other methods used for drilling the Weber sand. Two types of diamond coring are discussed. The first and the one used most extensively is the regular 6 ?x 3¾-in. diamond bit and bottom hole 50-ft barrel. The second type, which has also been used successfully by Stanolind, consists of a 4 13/16 x 2 11/32-in. cutting bit and reverse circulation coring equipment. The first type will be referred to as regular or conventional diamond coring while the latter type will be referred to as reverse circulation diamond coring. Introduction Diamond coring has been used for many years in mines, quarries, surface coring at dam sites, laboratory work, and so on, but, until recently, had never been used very extensively in coring oil sands and other oil-bearing strata. It was demonstrated early in its development that hard forma-tions could be cut rapidly and that core recoveries far exceeded those obtained with conventional hard rock bits and quite often 100 pet recovery was obtained. However, the poorly constructed diamond-coring equipment and resulting high costs of early diamond coring slowed down its progress. Early in the development Of the Rangely Weber field, Rio Blanco County, Colorado, the Rangely Engineering Committee selected key wells that were to core the Weber section in its entirety. These cores were to be analyzed and various sections tested to gather sufficient information so that accurate reservoir studies could be made. The number of wells selected were kept at a minimum inasmuch as the productive Weber section, which is found at an approximate depth of 6000 ft, is thick, being as much as 600 to 700 ft on top of the structure. The Weber section is also comparatively hard to drill. For instance, one well took 60 days to core 490 ft of Weber sand with conventional coring equipment. It was noticed, however, that Core Labora-verse diamond plug cutter could quickly cut a plug from. one of these hard cores. This fact led to the serious consideration of diamond coring the Weber sand. The first diamond coring at Randy was performed by Stanolind in August 1946 andl although we experienced some difficulties, the results definitely indicated that diamond coring would be successful at Rangely for .coring the Weber sand. As more wells were cored and the equipment improved somewhat, diamond coring became less expensive than drilling the Weber sand with the conventional rock bit. In less than one Year diamond coring has definitely Proved its usefulness in oil-field drilling operations in the Rocky Mountain area where formations quite often drill very hard. The practice of spot coring in hard oil-bearing formations with conventional coring equipment is giving way diaimond coring of the entire sections, thus givng an operator the complete picture.

Jan 1, 1948

By Carl J. Christensen

This paper presents the development of diamond coring of the Weber sand section in the Rangely Field, Colorado. The description and operation of the diamond-coring equipment is included as well as the economics and results obtained by its use. Diamond coring is compared with the other methods used for drilling the Weber sand. Two types of diamond coring are discussed. The first and the one used most extensively is the regular 6 ?x 3¾-in. diamond bit and bottom hole 50-ft barrel. The second type, which has also been used successfully by Stanolind, consists of a 4 13/16 x 2 11/32-in. cutting bit and reverse circulation coring equipment. The first type will be referred to as regular or conventional diamond coring while the latter type will be referred to as reverse circulation diamond coring. Introduction Diamond coring has been used for many years in mines, quarries, surface coring at dam sites, laboratory work, and so on, but, until recently, had never been used very extensively in coring oil sands and other oil-bearing strata. It was demonstrated early in its development that hard forma-tions could be cut rapidly and that core recoveries far exceeded those obtained with conventional hard rock bits and quite often 100 pet recovery was obtained. However, the poorly constructed diamond-coring equipment and resulting high costs of early diamond coring slowed down its progress. Early in the development Of the Rangely Weber field, Rio Blanco County, Colorado, the Rangely Engineering Committee selected key wells that were to core the Weber section in its entirety. These cores were to be analyzed and various sections tested to gather sufficient information so that accurate reservoir studies could be made. The number of wells selected were kept at a minimum inasmuch as the productive Weber section, which is found at an approximate depth of 6000 ft, is thick, being as much as 600 to 700 ft on top of the structure. The Weber section is also comparatively hard to drill. For instance, one well took 60 days to core 490 ft of Weber sand with conventional coring equipment. It was noticed, however, that Core Labora-verse diamond plug cutter could quickly cut a plug from. one of these hard cores. This fact led to the serious consideration of diamond coring the Weber sand. The first diamond coring at Randy was performed by Stanolind in August 1946 andl although we experienced some difficulties, the results definitely indicated that diamond coring would be successful at Rangely for .coring the Weber sand. As more wells were cored and the equipment improved somewhat, diamond coring became less expensive than drilling the Weber sand with the conventional rock bit. In less than one Year diamond coring has definitely Proved its usefulness in oil-field drilling operations in the Rocky Mountain area where formations quite often drill very hard. The practice of spot coring in hard oil-bearing formations with conventional coring equipment is giving way diaimond coring of the entire sections, thus givng an operator the complete picture.

Jan 1, 1948

By Daniel T. Hegyan, Thomas B. Zugates

Continuous vacuum disk filters are increasingly being used to filter refuse from the fine-coal washing circuits as it becomes important to close the water circuits and eliminate sludge holding ponds. This paper discusses our past experience filtering refuse, effects of solids concentration in the filter feed, use of polymer flocculation aids, effect of flocculation devices, and effects of particle size and ash content on the filtration rate. Detailed tests were performed on existing installations utilizing coal refuse filters to determine optimum flocculant dosage, solids concentration, and disk rotation speed to form a dischargeable cake. Information was also obtained showing effect of flocculant addition on the moisture of the filter cake.

Jan 1, 1977

By E. W. Parker

PROBABLY everyone is well aware that from April 1 to September 11, 1922, anthracite production was completely suspended; during those 163 days not one ton of coal was produced in the anthracite region. The production loss was about 30 million tons, and although production is now at its peak, there is no possible way by. which, within any short space of time, that deficiency can be made up. During that time the miners sacrificed in wages something over 100 million dollars. The anthracite companies paid out in cash, keeping their mines in condition to operate when mining should be resumed, something like 30 million dollars without taking in one cent of revenue. The tonnage of domestic sizes included in that lost output was about 21 million tons. The anthracite operators figured that between September 11, 1922, and March 31, 1923, they would possibly be able to produce about 60 per cent. of the tonnage that was mined the preceding year, that is, from April 1, 1921, to March 31, 1922. The problem then arose as to how that tonnage could be distributed equitably throughout the United States and Canada. We had in our records in Phila-delphia the distribution by communities, about 20,000 of them, to which anthracite had been shipped during the last five years, so that we were well posted as to what each community should be entitled to receive. We allotted to each of those 20,000 communities 60 per cent. of the tonnage that it had received during the preceding coal year, and we have endeavored to see that whatever tonnage we have been able to produce should be equitably distributed on that basis. It was a matter simply of voluntary cooperation by the anthra-cite operators who placed the distribution of their tonnage practically in the hands of the Pennsylvania Fuel Commission; the anthracite companies have almost without exception acceded to every request that we have made of them. When communities were reported entirely out of coal, a telegram or letter to the directors obligated to that community has resulted in some anthracite being shipped there, so that we have thus far kept the distribution on a fairly equitable basis. Prior to the suspension of mining operations, pre-liminary negotiations were carried on for the renewal of the wage scale, the operators thinking that it could be adjusted satisfactorily, and that the same method of procedure would be followed as during the 20 years succeeding the strike of 1902. At every termination of the wage agreement since that date, until last year, an agreement had been reached early in the season that mining operations should be continued, with the under-standing that any new agreement should be retroactive to April 1. At the meeting of the committees of anthra-cite operators and miners, on March 21, 1922, the opera-tors were presented with an ultimatum by the miners to the effect that unless an agreement were reached within ten days, mining operations would cease. That was protested against by the committee of operators as being unfair, not only to the operators and the public but to the men themselves. In spite of this protest the suspension occurred and, as you know, continued until September 11.

Jan 4, 1923

By Walter C. Labys, Fereidoon Shahrokh

This paper presents an application of computer simulation methods to the modeling and forecasting of the United States coal market. The computer methods employed as well as the model constructed are based on economic and econometric theory. The contents of the paper include a description of the coal market, the corresponding computer model, tests of model validation, computer generated scenarios for the period 1980-1985, and comparisons of the scenarios generated with that of other major coal forecasts.

Jan 1, 1983

By E. J. Haug, M. M. Fine

FOR several years work has been carried on by the U.S. Bureau of Mines at Rolla, Mo., to develop improved methods of concentrating the oxidized ores of lead and zinc. Various samples have been investigated, and results on some have been published 1,2 lished.l, 2 Details of the progress to date are given in a mineral dressing study now being conducted for an extensive oxidized lead-bearing tract in southeast Missouri, property of St. Joseph Lead Co. These oxidized ores present problems typical of many encountered in modern mineral dressing research in that recovery of very fine particles is of

Jan 1, 1956