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By I. A. Ettlinger

THE formation that the writer has chosen to call "The Central Arizona Batholith" is included in the Globe, Miami, Ray, Pioneer, Troy, and Silver King mining districts. Its extension to the southeast is in the Banner mining field. Basing his argument on what is known of batholithic intrusions, the author offers reasons for considering all these granitic outcrops as parts of a single great mass of plutonic rock. The United States Geological Survey has subdivided this area into three -quadrangles-the Globe, the Ray, and the Florence. Of the first two, geologic atlases1 have been published, but of the last, the topographic map alone is available. These mining districts include such prominent present-day producers as Inspiration, Miami, Old Dominion, Arizona Commercial, Iron Cap, Superior and Boston, Magma, Belmont, and Ray Consolidated. Among those well known in the past are Silver King mine and Gibson mine. Fig. 1 is a geologic map of the Central Arizona Batholith region. F. L. Ransome's excellent work on The Copper Deposits of Ray and Miami, Arizona,' is of great value to all workers in those districts. His geologic map for the Ray and Globe quadrangles has been incorporated in Fig. 1, and the stratigraphic names employed are those first applied and defined by him in his pioneer work in this region. The purpose of this paper is to show that the ores are related to post-Carboniferous granitic intrusions; that while there does not seem to be any adequate explanation for the distribution of all the igneous stocks, a preexisting structure does appear responsible for at least the location of the largest igneous stock of the region; that the principal producing vein mines are located in the sedimentary rocks in the roof of this batholith, while the disseminated copper deposits are found bordering the lower portions of the batholith exposed by erosion; that primary zoning is illustrated not only on a broad (district) scale but also on a small (individual

Jan 1, 1928

By means of top-slicing methods, wide veins, masses, or thick beds of soft ore may be mined, where the caving of the overburden is of no consequence. The ore is mined in a series of horizontal floors or slices, taken in descending order, from the top of the deposit. Each floor is mined in small sections, the roof of each section being allowed or forced to cave before an adjacent section is attacked. The method as used in two mining districts—Marquette, iron, and Pachuca, silver-gold—is described in the two papers following:

Jan 1, 1925

By H. J. Hand

Statistical methods are becoming increasingly important for interpreting routine reports, or for analyzing special test data in industrial plants, such as steel plants. They have already become practically a necessity to the plant metallurgist. A paper by Chancellor, 1 written in 1933, gives many examples of the benefits the plant metallurgist can derive from the use of these methods. The present paper discusses applications of importance to many others who must analyze reports in the steel plant, as well as other examples of interest to metallurgists. Statistical Methods Logically Suited to Plant Problems.—Statistical methods are not new as a branch of mathematics. Until comparatively recently, however, practical applications were confined mainly to actuarial science, biology, and economics; fields in which an observed result is obviously influenced (and often determined) by a complicated set of variables more or less constantly tending to affect it. As pointed out by Daeves,2 a decade or more ago, problems in industry are basically similar to those in these other fields in that a given result is at least partly due to that chance combination of causes happening to be present at the time. When trying to do the same thing repeatedly, constant results are never attained; they vary about the desired result with more or less well defined mathematical regularity. Such a condition arises out of the great number of factors tending to affect the final result. If statistical methods are so valuable to the biologist or economist, why then should they not also be of great value to plant managers and engineers, and to all who must interpret reports from various sources in the industrial plant? Within the last few years, industry has become conscious of this situation, and the use of these methods has been rapidly expanding in such p1ants. Many Useful Statistical Devices Available.—Many statistical methods of attack are available for the analysis of plant data. It is the object of

Jan 1, 1938

By H. J. Hand

Statistical methods are becoming increasingly important for interpreting routine reports, or for analyzing special test data in industrial plants, such as steel plants. They have already become practically a necessity to the plant metallurgist. A paper by Chancellor, 1 written in 1933, gives many examples of the benefits the plant metallurgist can derive from the use of these methods. The present paper discusses applications of importance to many others who must analyze reports in the steel plant, as well as other examples of interest to metallurgists. Statistical Methods Logically Suited to Plant Problems.—Statistical methods are not new as a branch of mathematics. Until comparatively recently, however, practical applications were confined mainly to actuarial science, biology, and economics; fields in which an observed result is obviously influenced (and often determined) by a complicated set of variables more or less constantly tending to affect it. As pointed out by Daeves,2 a decade or more ago, problems in industry are basically similar to those in these other fields in that a given result is at least partly due to that chance combination of causes happening to be present at the time. When trying to do the same thing repeatedly, constant results are never attained; they vary about the desired result with more or less well defined mathematical regularity. Such a condition arises out of the great number of factors tending to affect the final result. If statistical methods are so valuable to the biologist or economist, why then should they not also be of great value to plant managers and engineers, and to all who must interpret reports from various sources in the industrial plant? Within the last few years, industry has become conscious of this situation, and the use of these methods has been rapidly expanding in such p1ants. Many Useful Statistical Devices Available.—Many statistical methods of attack are available for the analysis of plant data. It is the object of

Jan 1, 1938

By W. C. Browning

The influence of the hydroxyl factor is more damaging to formations penetrated and causes greater consumption of drilling mud additives than previously realized. This hydroxyl effect on clays is essentially independent of the cations present in the drilling fluid and thus differs from the base exchange reactions that have preoccupied mud chemistry with sodium and calcium bentonite concepts for nearly two decades. The new organic polyelectrolyte-con-ditioned muds haw made it possible to use materials other than sodium hydroxide to maintain the alkalinity of such muds. The properties of silicates, as indicated by their dissociation characteristics and buffering action, are such that they can control he pH and alkalinity of drilling muds at the desired level and, at the same time, minimize undesirable hydroxyl effects associated with sodium hydroxide. This use of silicate compounds is different and distinct from prior applications of silicates as deflocculants or shale preservers. Laboratory and field data presented in this report show that silicate compositions can be utilized to adjust the alkalinity of drilling muds and, at the same time, minimize hydmxyl-promoted clay cleavage. INTRODUCTION Studies for improving the efficiency of rotary drilling techniques must consider the chemistry of drilling fluids and of the formations being penetrated. The chemical aspects of drilling must be studied in conjunction with and in relation to the mechanical factors if, for example, penetration rates are to be optimized. Drilling fluid technology has been largely influenced by chemical reactions of the montmorillonite (bentonite) clay minerals. Most of the literature of mud chemistry concerns the properties of bentonite. Clays of the kaolin or illite type, which are nonswelling, are not generally regarded as sources of drilling mud problems. If these nonswelling shale clays are considered, they are commonly regarded as inert solids. Particularly noteworthy is the fact that the relation of surface and colloid chemistry to massive shale bodies has received only scant attention from drilling technologists. Clay studies reported in the drilling mud literature have dealt, for the most part, with the properties of clays in a finely divided state, and often in very dilute suspensions. Yet frequently during drilling, shale problems not related to the rheology of clay suspensions develop in massive non-bentonitic shale sections of zero or near zero permeability. This paper is concerned with surface chemical reactions that can influence the behavior of these non-bentonite clay masses in such a manner as to adversely affect drilling operations. Browning and Perricone1,2 have pointed out that some of the most troublesome shales to drill, such as the Atoka, contain no montmorillonites. They also pointed out that mud problems can frequently be mitigated by reduction of clay cleavage achieved by using drilling fluids with a minimum of available hydroxyl ions. If pronounced clay cleavage occurs during drilling, the borehole may soften, increasing the possibility of sloughing. In addition, the resulting increased incorporation of high-surface-area clay solids into the mud system can reduce penetration rates and necessitate greater chemical treatment. This increase of shale, of colloidal or near-colloidal dimensions, into the drilling mud is due to clay aggregate cleavage and not to base exchange or swelling reactions, such as occur with bentonites. Searle and Grimshaw3 point out the difference between cleavage or slaking reactions of nonswelling clays (such as illite and kaolinite) and the swelling of bentonite. They further state that the speed of slaking is increased in alkaline water. Eitel1 cites Salmang and Becker, who recognized that clay surface reactions impart plasticity and workability to clay masses. Their results clearly show that all liquids which contain hydroxyl groups in their molecules favor the workability of clays. The ancient technique of aging clays in the moist condition to increase their "workability" is evidence that these clay cleavage phenomena are of considerable importance. The same hydration cleavage that occurs during the aging of nonswelling clays for ceramic use also acts to break up cuttings and soften the borehole during drilling operations. The mechanism of cleavage of the crystalline aggregates of illitic, kaolinitic and other nonswelling clays; and the chemical means of controlling this cleavage are therefore of considerable significance to the drilling mud chemistry. Inasmuch as there is little reference in the drilling mud literature to the cleavage reactions of nonswelling clays, the structure of these clays and certain properties that relate to the mechanism of clay cleavage will be reviewed briefly. STRUCTURE OF NONSWELLING CLAYS Clays such as kaolinite, illite and montmorillonite are compmed of alternate layers of (1) silicon-oxygen tetra-

Jan 1, 1965

By J. E. Russell

A brief review of the role of laboratory testing for characterization of host rocks for nuclear waste repositories is presented. Micro-and macro-scopic deformation mechanisms are discussed and constitutive laws being considered are reviewed. More information is available for rocksalt under expected repository conditions and, consequently, it receives more attention in our review. A brief comparison is made between the creep and constant strain-rate tests leading to a hypothesis that there may be systematic differences between steady-state conditions developed by the two test types. This difference is explained by considering specific power dissipated and work done on the sample. The hypothesis is tested against data for wet Westerly granite. In conclusion, progress has been made during the past five years but research and development should continue.

Jan 1, 1984

By A. M. Lovelace

Introduction One area of engineering utilization of materials in which the requirements are especially rigorous and demanding is that of aerospace systems, including aircraft, helicopters, missiles, and space satellites. Materials used in these systems must reliably perform many critical functions in a broad range of adverse environments. Some of the most critical functions are performed by polymeric nonmetallic materials such as elastomers (rubber), coatings, fibrous materials, and reinforced plastics. These types of polymeric materials have some common characteristics that make them attractive to aerospace system designers: light weight, corrosion resistance, and relative ease and low cost of processing and fabrication. Each type also has its own special characteristics that enable it to perform certain required functions better than other competing materials can (Table 1). The desirable properties of polymeric materials, which in some applications make them the only practical candidates, are partly offset by their principal limitation, which is degradation by exposure to high temperature. [ ]

Jan 1, 1971

By F. A. Schaufelberger

Early work on chemical precipitation of metals from metal salt solutions is reviewed. The chemistry and thermodynamics of precipitating copper, nickel, cobalt, and cadmium metals by reaction with hydrogen are discussed. Mechanisms of metal precipitation, nucleation, growth, and agglomeration are reviewed, as well as some solubility phenomena of gases and solids at elevated temperatures. Experimental data presented deal mainly with the reaction of copper sulfate solution with Hz.

May 1, 1956

By Charles White Merrill

Money is one of the most pervasive elements in human life. The compensation for a workman's daily efforts is expressed as a wage and is measured in money. What an individual may consume depends largely on his income which also is expressed in terms of money. If he would start an enterprise its size would be determined in large part by the amount of money available for capitalization and its success would be measured in net income expressed in money. In short, the most widely used common de- nominator for comparing merchandise, real property, jobs, enterprises, gross national product, or personal success is money. Despite this use of money by almost everyone past infancy to express his appraisal of the innumerable values he sees around himself, the complexity of the device called money makes its nature and workings a mystery to most users. Some of the difficulty in understanding money results from the fact that it has three distinct but interrelated functions: (1) a medium of exchange, (2) a unit of account, and (3) a store of value. In many statements about money the discussion moves from one function of money to another without the speaker or the listener recognizing the changes. For example, the housewife says "We took the money we had saved up to make the down payment and after twelve monthly payments the television will be ours." When this housewife spoke of "saving up the down payment" she referred to money in its function as a store of value; when she spoke of "the down payment" she was using money as a medium of exchange; and when she referred to the "monthly payments" she spoke of money as a unit of account. Another cause of confusion in understanding money is its paradoxical nature in that it represents both the power to produce and the power to consume. For example, when the rich uncle dies one nephew may regard his inheritance as an opportunity to buy a farm and leave the ranks of the wage earners to become an independent producer, whereas the other nephew may regard his portion as the means of living in complete leisure as a pure consumer.

Jan 1, 1964

Jan 1, 1918

CLEAR sunny skies that prevailed all through the 175th General Meeting of AIME were not the 1east of the details that resulted from the many months and man-hours of p1anning by the Southern California Local Section. Some 2600 persons left the 1953 Annual Meeting technically enlightened, having had a choice of over 300 papers presented by 400 authors to listen to, learn from, and criticize. During the meeting, Mike Haider turned over the Presidency of AIME for 1953 to Andrew (Drew) Fletcher.

Jan 4, 1953

By L. A. Delano

During 1916, the St. Joseph Lead Co. milled 2,505,670 tons of ore. This is a daily operating average of 7855 tons. The economic concentration of such a large tonnage necessarily requires a plant equipped with modern machinery and operated efficiently. The milling process used in producing this output has been a gradual development through the long period of years that the company has been in existence. HISTORICAL SUMMARY OF MILLING PRACTICE Ore was first mined at Bonne Terre, Mo., in 1864. The early milling practice was crude. It consisted of breaking the ore into small pieces by hand, pulverizing in a Blake crusher and a pair of Cornish rolls to approximately minus 6 mm., and jigging in the old-fashioned hand jigs. Only the coarse heavy galena was saved, the gangue being shoveled off and discarded. The output for the first year under this method was only 240 tons of pig lead. The first mill of the company was a combination of extensions and additions built from time to time as the mines developed. It was a museum of early milling machinery, such as jigs, percussion tables, buddies, dolly tubs, log washers, etc., following no definite flow sheet. The chats, or tailings, were hauled to waste dumps by mule and ox teams, as much as 500 tons per day being moved in this manner, until a railroad was built in 1880. This mill was burned in 1883, at which time the annual output had reached approximately 7300 tons of pig lead. A new mill of 500 tons capacity was designed and built by C. B. Parsons. This mill has been admirably described by H. S. Munroe.' The ore was crushed in Blake crushers, Cornish rolls, through 6-mm. screens, and treated by jigs of the Parsons type, percussion tables and log washers, or trunking machines, for cleaning the galena. The middlings were recrushed in rolls and treated on Harz jigs. The mill was operated without change, except later installing Gates crushers and en-

Jan 1, 1918

By John Wulff, H. H. Uhlig

Since its first mention in the literature in the eighteenth century12 the phenomenon of passivity in metals has stimulated much speculation and attendant controversy as to its nature and cause. No one of the numerous theories so far proposed has been generally accepted. ‡ Faraday,' in 1836, associated the passivity of iron with a protective film over the surface of the metal, which materially prevents or slows down reaction with corrosive environments. His theory was that oxidizing acids like nitric acid form an unstable oxygen or oxide layer over the iron surface, which protects the underlying metal from further attack. This concept was simple yet plausible, and without alteration has frequently been assigned in present-day discussions as explanation of the passivity of many metals. With the advent in recent times of stainless steels, it is not surprising that this oxide film theory of passivity proposed by Faraday has been used to explain the phenomenal corrosion resistance of stainless steels and other passive alloys. The passive alloys, such as the chrome-iron alloys, are supposedly covered with a protective oxide film, which forms on exposure of the alloy to air, is extremely stable and self-healing, and accounts for the remarkable resistance of these alloys to corrosion. Within the past few years, several investigators, following the theory of film protection, have attempted to gauge the resistance of the supposed film on steels. Brennert8 and Donker and Dengg9 determined the potential at which a negative ion (e.g., C1-) moving in an electric field reacted with the metal anode, as detected by increased current flow or change in potential of the steel electrode in an electrolytic cell. The potential corresponding to reaction Brennert called the film break-through potential.

Jan 1, 1939

By John Wulff, H. H. Uhlig

Since its first mention in the literature in the eighteenth century12 the phenomenon of passivity in metals has stimulated much speculation and attendant controversy as to its nature and cause. No one of the numerous theories so far proposed has been generally accepted. ‡ Faraday,' in 1836, associated the passivity of iron with a protective film over the surface of the metal, which materially prevents or slows down reaction with corrosive environments. His theory was that oxidizing acids like nitric acid form an unstable oxygen or oxide layer over the iron surface, which protects the underlying metal from further attack. This concept was simple yet plausible, and without alteration has frequently been assigned in present-day discussions as explanation of the passivity of many metals. With the advent in recent times of stainless steels, it is not surprising that this oxide film theory of passivity proposed by Faraday has been used to explain the phenomenal corrosion resistance of stainless steels and other passive alloys. The passive alloys, such as the chrome-iron alloys, are supposedly covered with a protective oxide film, which forms on exposure of the alloy to air, is extremely stable and self-healing, and accounts for the remarkable resistance of these alloys to corrosion. Within the past few years, several investigators, following the theory of film protection, have attempted to gauge the resistance of the supposed film on steels. Brennert8 and Donker and Dengg9 determined the potential at which a negative ion (e.g., C1-) moving in an electric field reacted with the metal anode, as detected by increased current flow or change in potential of the steel electrode in an electrolytic cell. The potential corresponding to reaction Brennert called the film break-through potential.

Jan 1, 1939

By L. E. Schiffman

This paper describes the operation of two kerosine flotation plants in Alabama for cleaning -10 mesh bituminous coal. One plant treats washer sludge, the other raw coal. Data on capacity efficiency and capital and operating costs is given. Methods for increasing cell capacity are discussed.

Jan 10, 1950

Jan 1, 1923

By C. E. Reinhard

A useful accelerated weathering test should be capable of placing any series of metals quantitatively in the same order of endurance as that noted under a particular set of actual exposure conditions. The development of such a test must necessarily depend to a considerable extent upon data obtained from a wide variety of exposures. This paper offers preliminary data from exposure tests on nine metals placed in 11 locations in the Lehigh Valley, within a radius of 20 miles from Palmerton. The exposure conditions vary from a severe industrial atmosphere to a pure rural atmosphere. The data are offered as evidence of the necessity for the identification and evaluation of the variables of corrosion and as illustration of some of the variations to be considered in the development of a useful accelerated test. It is quite clear, from this evidence, that a useful accelerated test must be versatile to the extent of showing the probable variations of corrosion resulting from differences in atmosphere as well as from differences in the metals. The paper is presented solely with the object of pointing out the wide variations in relative merits of several common metals in resisting corrosion and without any thought of initiating controversy regarding the merits of particular metals. For this reason the metals are designated only by symbols in the tables and no key is given to these symbols. Test Procedure Specimens, 4 by 6 in., were cut to accurate dimensions from each of the following metals or alloys: aluminum, ascoloy, copper, copper steel, galvanized iron, and zinc. Additional grades of these metals bring the total to nine types. Since it was impossible to obtain the required number of copper-steel specimens having equal surface conditions of rust and scale, it was thought advisable to pickle these specimens in a hot solution of 10 per cent. sulfuric acid. All other specimens were carefully cleaned in ether and alcohol and weighed just prior to exposure. Four specimens of each type of metal were mounted on a test rack by means of porcelain insulators. The racks were so constructed that

Jan 1, 1929

By C. E. Reinhard

A useful accelerated weathering test should be capable of placing any series of metals quantitatively in the same order of endurance as that noted under a particular set of actual exposure conditions. The development of such a test must necessarily depend to a considerable extent upon data obtained from a wide variety of exposures. This paper offers preliminary data from exposure tests on nine metals placed in 11 locations in the Lehigh Valley, within a radius of 20 miles from Palmerton. The exposure conditions vary from a severe industrial atmosphere to a pure rural atmosphere. The data are offered as evidence of the necessity for the identification and evaluation of the variables of corrosion and as illustration of some of the variations to be considered in the development of a useful accelerated test. It is quite clear, from this evidence, that a useful accelerated test must be versatile to the extent of showing the probable variations of corrosion resulting from differences in atmosphere as well as from differences in the metals. The paper is presented solely with the object of pointing out the wide variations in relative merits of several common metals in resisting corrosion and without any thought of initiating controversy regarding the merits of particular metals. For this reason the metals are designated only by symbols in the tables and no key is given to these symbols. Test Procedure Specimens, 4 by 6 in., were cut to accurate dimensions from each of the following metals or alloys: aluminum, ascoloy, copper, copper steel, galvanized iron, and zinc. Additional grades of these metals bring the total to nine types. Since it was impossible to obtain the required number of copper-steel specimens having equal surface conditions of rust and scale, it was thought advisable to pickle these specimens in a hot solution of 10 per cent. sulfuric acid. All other specimens were carefully cleaned in ether and alcohol and weighed just prior to exposure. Four specimens of each type of metal were mounted on a test rack by means of porcelain insulators. The racks were so constructed that

Jan 1, 1929

By Frank C. Appleyard

The two calcium sulfate minerals-gypsum and anhydrite-occur in many parts of the world, and gypsum has long been of economic importance in the family of industrial minerals. Gypsum, the dihydrate form of calcium sulfate (CaS042H20) and anhydrite, the anhydrous form (CaSO4) are frequently found in close association, and it is seldom that a calcium sulfate deposit will consist exclusively of one mineral or the other. Although known gypsum deposits are extensive, anhydrite makes up the largest part of total calcium sulfate reserves. However, it has very minor economic use, and most of the following discussion will be devoted to gypsum. Calcium sulfate is one of the principal con- stituents of evaporite deposits, and when pure, has the following composition: [ ] Deposits of pure gypsum or of pure anhydrite which are large enough to be considered commercial have never been found because of both the metastable relationship between the two minerals, and the presence of impurities such as calcium or magnesium carbonates, chlorides, other sulfate minerals, clay minerals, or silica. As a result most mine production of gypsum will range between 85 and 95% pure. Often it is used as mined, although in certain cases, one or more forms of mineral beneficiation are employed to upgrade the product.

Jan 1, 1975

By Ionel I. Gardescu

Natural gas influences the movement of oil through reservoir rock by affecting the physical properties of the oil and the pressure within the reservoir. The presence of gas bubbles changes the laws of flow and the distribution of forces. The problem of flow of oil and gas through a porous rock is complex, and most authors, in order to analyze their problems, have found it necessary to make or accept certain generalized assumptions. Some of these assumptions, particularly the ones dealing with capillary phenomena and moleculnr forces, have not received sufficient attention and by lack of understanding have often been misinterpreted. Herold1 has called attention to the resistance offered by gas bubbles in capillary spaces and has drawn some interesting conclusions with regard to the action of natural gas in a reservoir rock. He has duplicated an experiment of the French physicist Jamin, has interpreted his findings in terms of molar mechanics, and, from experimental observations, has made a number of assumptions which he later applies in discussing problems of natural flow and recovery of oil. The Jamin action is an assumption because it lacks a physical proof and has never been determined quantitatively. Tickel12 attempts to develop a formula expressing the work performed by a distorted bubble. H. A. Wilson, in the recent publication of the American Petroleum Institute on the function of natural gas, discusses the phenomenon in terms of classical physics. Both contributions are incomplete and offer no experimental data. This paper includes a study of the static condition of equilibrium of gas and liquid bubbles confined to capillary spaces. In order to avoid any possible confusion, it is proposed to restrict the term "Jamin action"

Jan 1, 1930