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By J. B. Ackerman, J. D. Miller

Alunite [KA13(S04)2(OH)6] is a promising non-bauxitic aluminum resource, the domestic reserves of which are estimated to be 800 x 106 tons at 35 percent alunite. The major gangue mineral associated with alunite is quartz. The thermochemical process that has been developed for treatment of this ore does not provide for the initial removal of gangue prior to processing. In this regard, it may be desirable to concentrate the ore to gain significant technical and economic advantages. Experimental results indicate the effectiveness of an oleic acid flotation technique and exemplify the problems encountered in fine particles processing. These results show that the quality of separation studied as a function of temperature, collector addition, and depressant addition is dependent on the degree of liberation achieved during size reduction. At coarse grinds the quality of separation was limited by the presence of locked particles while for finer grinds where more extensive liberation is achieved, better separations were obtained. The degree of liberation for each size interval was determined by an SEM/energy dispersive x-ray technique and found to be independent of the extent of size reduction, suggesting that liberation occurs by indiscriminate fracture and not by detachment. Up to 89 percent liberation was realized for a minus 400 mesh grind. Under these circumstances, the quality of separation appears not only to be limited by the remaining locked particles, but, also, by contamination of the alunite concentrate with fine quartz gangue (< 2µm). The best separation for the minus 400 mesh grind was a rougher recovery of 88 percent with a grade of 65% alunite at 50°C.

Jan 1, 1980

By Milton Williams

IT is generally recognized that fluid is lost from rotary drilling mud s to permeable strata during normal drilling operations;1,2,3 but that this fluid is the filtrate from the mud, rather than the mud itself, has been shown by various workers.1,4,5 . The presence of this filtrate in oil-bearing or gas-bearing strata is undesirable and harmful. The decreased permeability of the stratum to oil effected by the presence of water has been pointed out by several investigators,6,7 and since, in the production of the reservoir fluid, the greatest pressure drop occurs immediately adjacent to the borehole, it follows that infiltered water is particularly objectionable in this region. Again, this filtrate tends to make electrical logs less reliable, since oil in the proximity of the borehole is probably flushed out to an appreciable ent by the water.8 Observation of side wall cores may be misleading for the same reason. Drill-stem tests in low-pressure areas may be of doubtful value where no oil is recovered, unless sufficient time is allowed for production of water lost from the mud. The infiltered water may hinder drilling operations by softening shales and causing sloughing; the "tight hole" occasioned by excessive deposition of filter cake in the hole is a common occurrence. The filter cake remaining on the face of the producing formation may itself sometimes be detrimental to production.9 In view of these implications of the importance of filtration of mud, an investigation was undertaken to determine the factors involved in the infiltration process, and to correlate these in such a manner that the values obtained in routine filter tests employing a conventional filter of the "wall-building tester" type,10 together with data on size of hole, drill pipe, and rate of mud circulation, could be used to estimate water loss and distance of penetration of the filtrate into strata.

Jan 1, 1939

By Fred Wright

IN A recent paper1 a detailed discussion is given of the possibilities. of using polarized light in the examination of opaque substances. The factors underlying the problem .are there treated from the viewpoint of the electromagnetic theory of light and the presentation is necessarily mathematical in form. The practical methods resulting from the discussion are, however, relatively simple and promise to be of value in the determination of certain ores and metals when studied in reflected light under the microscope. The results of the theoretical investigation referred to may be summarized by stating that in general the optical constants, such as refractive indices and absorption indices, cannot be satisfactorily ascertained on small, random, polished sections; that the use of polarized light enables. the observer ordinarily to determine whether the crystal plate is isotropic or anisotropic, and also to ascertain the degree of anisotropism; that for this purpose methods based either on the contrast in intensity between the two reflected components of non-polarized light, or on the amount of rotation of the plane of polarization, on reflection, of vertically incident, plane-polarized light, may be employed; that methods based on the phase difference between the two reflected components are in general of little value because of the small differences in phase which ordinarily result for a relatively large change in birefringence or biabsorption. The measurement of the optical properties of transparent minerals, even in minute irregular grains, is a simple task with modern petrographic microscope methods and is accomplished by petrologists as part of their ordinary routine work. But the determination of the optical constants of opaque substances is difficult and is rarely attempted; all observations are necessarily made in reflected light and are restricted commonly to the determination of color, of hardness, of the character of crystallization, and

Jan 2, 1920

Jan 1, 1890

By Bernard N. Moore

At present the demands of the United States for strorltium are met by imports from Germany, England and Canada, which vary considerably in proportions of ore and finished salts, in tonnage and in value. Statistics for the period 1926-1932 are given in Table 1. Domestic deposits arc known in many states, but the larger and purer ones are in the West, particularly in the desert region of southeastern California and western Arizona. These deposits are large enough to command interest, particularly in consideration of future cheap power at the Boulder Dam. The deposits described in this paper were examined during an investigation of the mineral resources of the Boulder Dam region by the United States Geological Survey for the United States Bureau of Reclamation in the spring of 1934. Mr. D. F. Hewett, who had general charge of the investigation, Mr. W. T. Schaller and Mr. M. I. Goldman contributed many helpful suggestions. Mr. N. H. Harshman assisted efficiently during the field work. Celestite Deposits The celestite deposits described in this paper are of sedimentary origin and Tertiary age. They are widely scattered, as shown on Fig. 1,

Jan 1, 1935

By T. B. Gyles

Zinc is made by the National Smelting Co. and its associates by both the horizontal retort process and the vertical retort process developed by the New Jersey Zinc Co. This paper deals only with the horizontal retort practice at Avonmouth. That the horizontal retort process does survive in all countries in some form or other is due to at least partial success in overcoming some of the inherent difficulties of the process. The horizontal retort furnaces ran into considerable difficulties when the product of the selective flotation of mixed lead and zinc ores became the normal material for treatment. It is necessary, therefore, to make some reference in connection with the process to the preliminary treatment of the ore prior to distillation.. Therefore we include some small reference to this aspect in our description. Furnace Design and Structure Of the types of furnaces in operation at the company&apos;s various works, those at Avonmouth are perhaps more typical of the trend to utilize large units, with a subsequent saving in costs, such as heating and supervision.

Jan 1, 1937

By H. H. Taft

The mining possibilities of the volcanic area south of Bel-mont, Nye county, Nevada, have long been known. Some of the old-time prospectors knew that gold existed there. Its remoteness from any source of supplies, its long distances from water, the absence of game, and more, perhaps, the lack of grass for animals to subsist upon, has made this an unattractive region in which to search for mines. The decline of the Comstock mines, the exhaustion of sundry large and rich ore-bodies, the high cost of mining, marketing, and, particularly, the ruinously high freight-charges upon refractory ore that had to be shipped to distant smelters, have kept investors out of Nevada for the last few gears; and mining people have hardly yet awakened to the importance of To-nopah, Goldfield, and perhaps the newer and less developed districts. The discovery of Tonopah by J. L. Butler, who located the Mizpah claim in May, 1900, and the fortunes soon realized there, attracted many people. As the boom declined, many went away, some scattering out into the surrounding country, and the population is now about 7,000. In the fall of 1902 a discovery of gold was made 23 miles south, in what is now known as the Sandstorm group, 4 miles NW. of Goldfield. In the winter of 1903—4 the Combination, January and Florence mines were discovered, and shipments of high-grade ore soon followed. In January, 1905, there were 10,000 people in Gold-field. In June, 1904, rich gold-ore was found 85 miles SE., at the foot of the south end of the Kawich mountains, but this discovery was kept quiet until a re-location could be made. On August 10, 1904, the Bullfrog claims, and a month later the Ladd mountain and neighboring claims, were located. The Shoshone group was located September 24. This district is

Jan 1, 1907

By Bernard N. Moore

At present the demands of the United States for strorltium are met by imports from Germany, England and Canada, which vary considerably in proportions of ore and finished salts, in tonnage and in value. Statistics for the period 1926-1932 are given in Table 1. Domestic deposits arc known in many states, but the larger and purer ones are in the West, particularly in the desert region of southeastern California and western Arizona. These deposits are large enough to command interest, particularly in consideration of future cheap power at the Boulder Dam. The deposits described in this paper were examined during an investigation of the mineral resources of the Boulder Dam region by the United States Geological Survey for the United States Bureau of Reclamation in the spring of 1934. Mr. D. F. Hewett, who had general charge of the investigation, Mr. W. T. Schaller and Mr. M. I. Goldman contributed many helpful suggestions. Mr. N. H. Harshman assisted efficiently during the field work. Celestite Deposits The celestite deposits described in this paper are of sedimentary origin and Tertiary age. They are widely scattered, as shown on Fig. 1,

Jan 1, 1935

By Frederic E. Carter

The gold, silver, copper alloys have been the subject of several fairly complete investigations by Janecke, Sterner-Rainer&apos; and others, and indeed it would seem as if almost too much labor had been expended on them when one thinks of the numerous other ternary alloys calling for more light; however, the combinations of the three metals are actually so widely used in jewelry that they merit perhaps the work done on them. There are a few properties of importance and interest not treated by the authors mentioned which the writer investigated some little time ago, and therefore he has ventured to put on record the results of some of his tests made at that time. He has chosen, as being the two series of most importance to the jeweler, only the 14 and 18-kt. golds, so the subjcct is by no means so inclusive as that previously treated. As statecl, this paper is merely a record of tests made in a practical manner on two itucbful series of alloys, and is not at all a critical study of their properties. 14-Karat Alloys These alloys are important because they arc the most generally II,<(S(I in 14-kt, jewelry; by changing thc proportions of silvcbr and copper Iliero are obtained all shades of color from the green of the alloy contiainng gold and silver but no copper, to the red of the alloy containing gold ;,, copper but no silver. Many 14-kt. gold alloys are made with the sdditjon of zinc to the three metals mentioned here; the added lnetnl does not appreciably alter the color of the alloy nor has it, in general, much effect on the working properties; it may, however, prove useful as ynrt of thc zinc added may act as a deoxidizer and render the alloy free of ga,s. 11, iy not a necessary addition because with proper precautiolls :111 I lie 14-At. gold alloys containing only silver and copper in :tcltlitiotl to the gold ran be made free of gas and capable of being cold rolled without craci The alloys in which approximately equal quuntiticrs of silver ami

By Francis S. Kendorski

Caving offers the lowest cost per ton of ally large-scale mining method, but its successful application demands an ore body that conforms to several rigid requirements. The deposit must be of wide areal extent, massive and not spotty in ore values, and insensitive to ore dilution. It must also be a rock mass that breaks up readily. There are only three active caving operations in the US-Climax, Henderson, and San Manuel-but caving methods have recently-taken on new importance as deeper, lower grade mineral occurrences and ore bodies are found. These deposits are too deep for surface mining methods, and too low grade to support any type of underground mining except a bulk method such as caving.

Jan 6, 1978

By M. Earl Volin, M. Adnan Goksel

The hydro thermal agglomerating process described (U.S. Pat. No. 3,235,371, 1966)* is different from the cotzventional high-temperature processes. Green pellets or briquettes made with mixtures of moist iron-ore concen- trates and burned or hydrated lime fines are hardened in an azttoclave at 198°C and under steam pressure for 112 to 5 hr, with or without previous drying. Under the neutral conditiotzs, oxidation of magnetite does not occur as in the conventional processes. The resulting azzlomerates-- are hard and resistant to abrasion and weathering, and they do not disintegrate in the Under test. The equipment required for the process is not complicated, and favorable operating costs are projected because of the low temperamre and efficient heat recuperation. A low capital investment makes the process attractive even when the annual pellet production is below a million tons.

Jan 1, 1970

By Edward Wisser

THE Pachuca silver district, situated about 100 kilometers northeast of Mexico City (Fig. 1), covers roughly the southeastern half of the Sierra de Pachuca. The latter is a mountain range with northwest trend, and forms a part of the northeastern rim of the topographic basin known FIG. 1.-LOCATION OF PACHUCA DISTRICT AND OTHER MINING CAMPS. as the Valley of Mexico. The length of the Sierra proper is about 50 km., its greatest width about 9 km., and it rises to a maximum of 600 meters above the general level of the basin floor. The Pachuca district consists of two contiguous subdistricts, the Pachuca area and the Real del Monte area. The center of the Real del

Jan 1, 1936

By Robert Schorr

PAGE 1. Introduction,........... 82 2. Characteristics of Briquettes,........ 87 3. The Manufacture of Coal- and Coke-Briquettes,.... 89 Binders, Organic and Inorganic,...... 90 Mixing,...........94 Presses, Continuous and Intermittent Action,....95 Cost of Briquettes and Sales-Prices in Various Countries,.. 99 4. The Manufacture of Peat-Briquettes,......101 Solid Peat-Slabs,.........101 Solid, Carbonized Peat-Briquettes,......103 Estimates of Cost of Operating Peat-Briquetting Plants,... 105 5. Manufacture of Mineral-Briquettes for Metallurgical Processes,.. 108 6. Manufacture of Artificial Stone-Masses,......112 7. Bibliography,...........115 Introduction. Briquetting is apparently a very simple operation, yet it has offered so many mechanical and chemical difficulties that it required almost a century to place it on a commercial basis. Since 1860, however, the progress has been steady and satisfactory, and to-day, for most of the European coal companies, the briquette-plant is a very profitable investment. Among the many applications of scientific knowledge to further economy by recovering and utilizing by-products and raw materials, there is possibly none which deserves the attention of Americans to a higher degree than briquetting. The recent miners&apos; strike in Pennsylvania, which resulted in a scarce and irregular supply of coal at a high price, has advanced the possibilities for briquetting, and as a consequence public interest has grown rapidly. While the manufacture of coal-briquettes is not new in the United States, adverse conditions and sometimes lack of

Jan 1, 1905

By Lo-Ching Chang, K. M. Goldman

The kinetics and mechanism of transfer of a constituent across a slag-metal interface are fundamentally important because many metallurgical processes involve the existence of a slag phase and a metal phase. Industrial processes seldom proceed to equilibrium, and information of the rates and modes of reactions are therefore often of greater practical importance than equilibrium data. A study of the kinetics of sulphur transfer across a slag-metal interface under reducing conditions will contribute a great deal toward a better understanding of desulphurization in the blast furnace process. The general principles existing in the transfer of a constituent, such as sulphur, across a slag-metal interface can be extended to similar transfer phenomena in other metallurgical processes. The present paper will demonstrate how such studies will lead to fruitful results from both the practical and theoretical standpoints. EXPERIMENTAL METHOD The apparatus used was, simple. A graphite crucible 15/8-in. id, a wall 1/8-in. thick, and a depth of 4 in., was packed in an outer fused silica tube with powdered magnesia. The crucible assembly was rotated at a speed of 235 rpm inside an in- duction coil. A charge of 250 g of Armco ingot iron was introduced into the graphite crucible and melted by induction heating. The melt was held at a desired temperature for 3-5 "&apos;in., aftcr which 7.5 g of granular ferrous sulphide was added and the bath was held for another 3-5 mi11. A metal sample was then taken by means of a fused silica tube and a rubber suction bulb. Immediately after the metal sample was taken, 30 g of a prefused and crushed slag were introduced. The slag reached the ternperature of the furnace in 1 to 1 1/2 min. Slag

Jan 1, 1949

By Sidney H. Loram

As the work carried on by this Company, of which the writer has been in charge for the past two years, is somewhat unique, the following account of it may be of interest, and, on that account, is offered to the Institute without any attempt to claim this practice as the best. Mines. The mines supplying ore to the Company arc situated in three groups: the Guanaco field,.about 80 miles N.E. of the port of Taltal (lat. 25" S., long. 70" 30&apos; W. of Greenwich); the Sierra Overa, about 63 miles S.W. of Taltal; and Paranao, about 42 miles due N. of Taltal (12 miles N. of the small town of Paposo, once famous for its copper-output). Guanaco. This field lies in the center of an absolutely waterless mountainous desert, where not a sign of vegetation can be found for miles. The dryness is such that ivory and horn crack and open, while raw-hide must be used in place of leather, which -would become worthless in a very short time. Water is brought about 21 miles by piping from the Cordillera, but only in small quantities, and costs in the Guanaco $7 (= $1.78 gold) per cubic meter. All supplies and food are sent from the port of Taltal, which in turn draws its supplies from the south of Chile, the

Jan 1, 1900

By H. G. Warren, E. W. Hough

Correlation of interfacial tension of the methane-n-pentane and methane-n-decane systems was made by Hough and Stegemeier by the use of the Weinaug and Katz equation. The methane-n-heptane and ethylene-n-heptane systems were investigated by the authors. Additional systems taken from the literature were the me thane-propane system by Weinaug. and Katz, the methane-n-butane system by Pennington and Hough, and the n- butane -carbon dioxide system by Brauer and Hough. These systems were analyzed by the Weinaug-Katz equation and the Sugden equation on the IBM 1620 11 computer using a regression analysis program. Parachor and exponent values for each component and system were determined. The experimental work was close to the critical point of the light component in the n-butane-carbon dioxide and ethylene-n-heptane systems, between the critical points of the light and heavy components in the methane-n-pentane, methane-n-heptane and methane-n-decane systems, and close to the critical point of the heavy component in the methane-pmpane and methane-n-butane systems. An empirical formula was developed to find a value of the constant B in the Sugden equation for binary hydrocarbon systems from the parachor values of the two components. Interfacial tension for binary hydrocarbon systems was found to be a direct function of liquid-vapor phase density difference in the same manner as a single-component system. DISCUSSION Interfacial tension may be defined as the measure of the specific free surface energy between two phases having different compositions.1 The interfacial tension (IFT) for a binary system may be predicted for any temperature and pressure if the

Jan 1, 1967

By K. M. Goldman, Lo-Ching Chang

The kinetics and mechanism of transfer of a constituent across a slag-metal interface are fundamentally important because many metallurgical processes involve the existence of a slag phase and a metal phase. Industrial processes seldom proceed to equilibrium, and information of the rates and modes of reactions are therefore often of greater practical importance than equilibrium data. A study of the kinetics of sulphur transfer across a slag-metal interface under reducing conditions will contribute a great deal toward a better understanding of desulphurization in the blast furnace process. The general principles existing in the transfer of a constituent, such as sulphur, across a slag-metal interface can be extended to similar transfer phenomena in other metallurgical processes. The present paper will demonstrate how such studies will lead to fruitful results from both the practical and theoretical standpoints. EXPERIMENTAL METHOD The apparatus used was, simple. A graphite crucible 15/8-in. id, a wall 1/8-in. thick, and a depth of 4 in., was packed in an outer fused silica tube with powdered magnesia. The crucible assembly was rotated at a speed of 235 rpm inside an in- duction coil. A charge of 250 g of Armco ingot iron was introduced into the graphite crucible and melted by induction heating. The melt was held at a desired temperature for 3-5 "&apos;in., aftcr which 7.5 g of granular ferrous sulphide was added and the bath was held for another 3-5 mi11. A metal sample was then taken by means of a fused silica tube and a rubber suction bulb. Immediately after the metal sample was taken, 30 g of a prefused and crushed slag were introduced. The slag reached the ternperature of the furnace in 1 to 1 1/2 min. Slag

Jan 1, 1949

A development drilling and bulk sampling program should furnish the following information: (1) geology of the mineralized zone, (2) quantitative data on grade and tons of material within pertinent cutoff limits, (3) physical size and shape of the deposit and areas underlain by waste as well as ore, (4) mineralogical and metallurgical characteristics of the ore, (5) physical characteristics of the ore, (6) bulk samples for metallurgical testing and grade, (7) data on factors that affect mining operations, such as ground water and ground conditions. The method and equipment best suited for a particular drilling job depend upon the geologic features of the mineral deposit to be tested.

Jan 10, 1967

By Don C. Blackmar

The production of non-ferrous secondary metals has become a large and important industry in the United States, and deals with practically cvery type of manufacturing concern. Its business is unique in that it generally buys frorn its customers as well as sells to them, whether they are individuals, cities, corporations, or the United States government. Its operations are of vital importance to the success and prosperity of nlany of the nation&apos;s most important manufacturers; yet there are few industries about which less is generally known by those outside it, whether concerning the rliagnitude of its operations or the details of its actual technique. The industry itself is to blame for this meager publicity, because its technical men have made few attempts to openly exchange ideas, in spite of the excellent examples set by the iron and steel or the copper and brass industries. Whether this is due to the ancient shroud of secrecy generally supposed to cover smelting operations, or because its technical men actually felt that the industry was too puny to be interesting, is hard to say. This paper will consider its subject in a general way, attenlpting to show something of the size and importance of the industry, as well as its fitness to do its work well. Attention will be called to the sound economic reasons for the handling of non-ferrous wastes by specialists, and to the often unseen losses of metals and labor which occur when manufacturc~rs rcclairn thrir own metallic wastes. Magnitude of the Modern Industry No particular thought is given to the kitchen accident whereby a ruined saucepan is sorrowfully tossed into the ash can, yet it is a fairly safe guess that within a month this saucepan, together with hundreds of its follows, will again be in service, perhaps in an autonlobile crankcase, or in an electric vacuum sweeper. It is by this conversion of the useless into the useful, whether from home or large manufacturer, that the secondary tonnage is built up.

By L. C. Morganroth

From a geological standpoint, but scant attention has been paid to fire-clay beds. Only within the last few years have they been the subject of individual investigation, prior to this time having been considered only in their relation to coal seams. While the relative importance of coal and fire clay is still immeasurably in favor of coal, yet an industry as large as that of fire clay is entitled to a measure of attention. A discussion of the Carboniferous clays is practically a discussion of the clay beds in the Appalachian basin, since more than 90 per cent. of these clays mined are from this region. The clays are confined to the northern end of the basin, or the States of Pennsylvania, Ohio, Kentucky, Maryland and West Virginia, ranking in importance about in the order named. The clay deposits of the Carboniferous period have been divided into two classes; those found in the Pottsville conglomerate series of rocks, &apos; and all those that are found in the formations above, for the reason that the clay beds above the Pottsville series all resemble each other in properties, composition and appearance, and all are distinctly different from the bed found in the Pottsville formation. The bed of clay found in the latter formation is unique in that flint clay is practically restricted to it. (A variety of flint clay is occasionally found in these upper deposits but this is in such small amounts as to be negligible.) Carboniferous clays occur between stratified rocks; sandstones, limestones, etc., in the same manner as coal veins. They are often accompanied by a coal vein although where the clay is of a workable thickness, the coal is generally too thin to work. The clay beds are sometimes known by the name of the coal seam at which horizon they occur. Clay beds may be from a few inches up to 20 ft. in thickness. They may consist of all soft clay, all flint or both soft and flint. The Carboniferous clay beds of Pennsylvania are the most important of any of the clay beds found in the country, and are among the oldest ones worked. We know more about this clay geologically for the reason

Jan 1, 1916