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By S. C. Langdon, Henry S. Rawdon

The following note describing the behavior of copper under rather unusual conditions is offered for its suggestiveness rather than as a complete study of the question. The examinations described were made because of a request for information concerning the embrittlement of copper when heated in a molten salt bath (sodium chloride) for the purpose of cleaning, as well as softening it. It is well known that metals may be rendered very brittle by electrolytic action in aqueous solutions, in all probability by the action of nascent hydrogen, and it was suspected that perhaps the embrittlement of the copper by means of the molten salt was produced in a somewhat similar manner. It was found that the copper was in contact with iron (or steel) while immersed in the molten salt, through the occasional use of an iron stirring rod, iron forceps for handling the pieces, and an iron pot for containing the fused salt. In the electrochemical potential series iron and copper stand some distance apart, copper being electronegative to the iron. Assuming that the two metals bear 2 similar relation to each other, when immersed in a bath of molten salt, as they do in an aqueous solution, they would be expected to form a galvanic couple, the copper being the cathode. By this means the copper might be embrittled, as often happens in aqueous solutions, by the action of the liberated hydrogen. In this case, however, the embrittlement must be attributed to some other agent than hydrogen. TO demonstrate how copper may be embrittled under these conditions, two small rods, one of copper and the other of mild steel, approximately 3/8 in. (9.5 mm.) in diameter, were immersed in a bath of sodium chloride that had been heated somewhat above its fusion point (melting point of sodium chloride is 801" C.) and an electromotive force of approximately 6 volts from a storage battery was impressed upon the system. The copper was made the cathode and the action was continued for several minutes. When removed from the bath, cooled, and tested for brittleness by bending the specimen back and forth, while clamped firmly at one end in a vise, the copper rod was found to be very brittle, as compared with a rod of the same length of the untreated copper tested

Jan 1, 1921

AN intermetallic compound, Ni3A1, has an ordered fcc structure of type Ll2, and shows peculiar dependence of the yield stress upon temperature; i.e., the yield stress increases by a factor of six upon raising the temperature from 77" to 900K1, 2 This compound is technologically important, since many nickel-base superalloys owe their high-temperature strength to the peculiar yield stress behavior of Ni3Al. The only study of the elastic behavior of this compound was made by Davies and Stoloff,1 who determined Young's modulus of poly crystalline Ni3A1 between 300" and 730°K. The determination of single-crystal elastic constants of Ni3A1 is therefore of interest in connection with dislocation dynamics and is reported in this paper. A single-crystal specimen, 1 by 1 by 3 cm, was cut from an ingot generously supplied by Dr. B. H. Kear of Pratt & Whitney Aircraft. Following initial machining with a Servomet and a surface grinder, the specimen was etched and annealed at 1100°C for 5 hr in vacuum followed by furnace cooling. Two parallel faces were oriented normal to within ±l deg of a [I101 crystallographic axis by the back-reflection Laue technique. The parallel faces were hand-lapped, etched, and polished by the usual metallographic procedures. Final thickness along the [I101 axis was (0.9325 * 0.0005) cm. Chemical analysis gave an average composition of 87.35 pct Ni. Total impurity content is esimated to be no more than 0.1 pct. The elastic constants were calculated from measurements of ultrasonic waves which were propagated along the [110] axis. A longitudinal wave and two shear waves whose displacements are aligned along the [ 110], [li~], and [001] directions, respectively, are necessary in order to completely specify the three elastic constants. Two 3/6-in. quartz transducers were bonded to the parallel faces of the sample with ~ac-seal.3 Although this bond was sensitive to thermal shock, it performed satisfactorily over the entire temperature range for both longitudinal and shear wave propagation. A frequency of 5 mHz was employed in the method of Williams and Lamb4 in order to measure the absolute value of the ultrasonic velocity. The pulse-overlap technique of Mcskimin5 was also used at this frequency in order to determine the shift in the ultrasonic velocity

Jan 1, 1970

By R. W. Bartlett

Hydrometallurgical processes for copper flotation concentrates avoid the SO2 emission problems associated with smelting, but they require oxidation of copper to obtain solubilization during leaching. The resulting copper ions must be reduced to metal, which normally requires large amounts of energy or energy equivalent reagents such as hydrogen or iron. The conventional reduction method is electrowinning which is labor intensive and involves 35 to 40% of both the entire operating and capital cost of the better hydrometallurgical processes. There is considerable incentive to reduce the cost and energy required for producing copper ions from solution. Furthermore, it is thermodynamically possible to do this using sulfur contained in the concentrate itself. In fact, the thermodynamic potential of oxidizing sulfur from S+4 to the S+6 state is greater than required to reduce cupric ion to metallic copper.1 Realization of this potential in a practical process would significantly reduce the cost of hydrometallurgical processing of sulfide concentrates because sulfur would become a cost-free reducing agent. An apparently practical method is to use SO: and HSO3 ions, obtained by ammonia scrubbing of SO2 from a concentrate roaster gas, to reduce leached copper to metal in an autoclave. This reduction step is the Jumau 1907 A series of steps, including sulfite reduction, constituting a crude flowsheet was suggested by Parker in 1976.3 The present paper describes a detailed complete. sulfite process flowsheet based on materials and energy balances, discusses the chemistry, and discusses further work that is required to develop this process. Process materials, utilities costs, and energy requirements are projected to be unusually low because of the utilization of sulfur from the concentrate. Process Description The sulfite reduction process requires a copper concentrate containing approximately as much sulfur on a weight basis as copper. For those few concentrates that are deficient in sulfur, additional sulfur can generally be obtained by allowing more pyrite to float in the concentration process. The process steps, shown in [Fig. 1], are (1) a fluid bed roast of the concentrate, (2) a leach of the roaster calcine using recycled barren liquor from the reduction autoclave, (3) scrubbing of the SO2 gas with ammonium sulfite liquor to produce ammonium bisulfite, (4) reduction and precipitation of copper in an autoclave by combining part of the SO2 scrubber effluent (SO5

Jan 1, 1980

By Ernest Gayford

THIS is a nontechnical paper on flotation, subdivided under three general headings: (1) Definition of flotation; (2) what flotation is now doing in Utah; and (3) what is the future of flotation? . DEFINITION T. A. Rickard defines flotation1 as "the act or state of floating," from the French flottaison, water-line and fitter, to float. The dictionary defines flotation as "the science of floating bodies." The flotation process is a method of concentrating ores by frothing. Weinig and Palmer 2 define flotation as follows: What is the flotation process? Briefly, it consists in the agitation of finely divided ore in water containing bubbles of air or gas, a small amount of oil and, usually, other reagents, soluble and insoluble; under these conditions the small parti- cles of native metals, sulfides, arsenides, antimonides, selenides and tellurides show a tendency to attach themselves to the 6lms of the bubbles, and are thus carried to the surface of the water. The oxidized gangue minerals, such as quartz, feldspar, limestone, hematite, etc., show much less affinity for the bubbles, are easily wetted by the water, and either remain in suspension in the water, or sink to the bottom of the vessel. If the bubbles are sufficiently stable they can be removed, carrying their load of sulfide-mineral particles with them. Thus there can be effected a separation of the two classes of minerals from each other, assuming that the grinding has been sufficient to unlock all of the particles of different composition. The separation does not depend upon differences in specific gravity of the various minerals; in fact, the sulfides are usually heavier than the oxides, and some of the heaviest sulfide minerals are the easiest to float. A particle of mineral may be so large, however, that its weight will counteract its affinity for the film of the bubble. In most cases the ore must be fine enough to pass a screen having at least 48 meshes to the linear inch. Taggart defines flotation as follows : Flotation is a method of wet concentration of ores in which separation of mineral from gangue is effected by causing the mineral to float at or above the surface of a body of liquid pulp while the gangue becomes or remains submerged. The method

Jan 1, 1928

By T. L. Joseph

THE committee appointed to investigate the application of oxygenated air to the blast' furnace believes, after a careful study of the problem, that this enriched air will increase hearth temperature, tonnage, flexibility of operation, and quality of pig iron made, and that fuel consumption will be decreased. These improvements are supported by theoretical evidence; but a practical trial of the process is necessary to establish more definitely the magnitude of benefits realized. The commercial application, however, may profitably be preceded by a test on a smaller scale. A small furnace will, in general, respond to the enriched air in the same way as a commercial furnace and the magnitude of the benefits to be gained from varying additions of oxygen can be fairly well established at relatively little expense. A new experimental furnace, being built jointly by the Bureau of Mines and the University of Minnesota, at Minneapolis, will have a capacity of about 6 tons and will riot require more than 700 cu. ft. of natural air per minute. Its hearth is 36 in. in diameter and its height about 32 ft. Enough oxygen to enrich the blast to the extent recommended by the committee can be obtained from a small oxygen unit. It might even be cheaper to perform preliminary experiments with tanks of oxygen obtained from regular, dealers. A procedure in making the test that suggests itself is to start with operation on normal air; then to use blast, enriched in several steps. Systematic temperature measurements of the tuyeres, slag, and metal would reveal any changes in hearth temperature. When these changes become large enough, the burden may be gradually increased to just within the breaking point and the furnace brought back to normal, if possible, by the addition of oxygen. Such a test would show what might be expected in the way of a decrease in fuel consumption and the time taken to "straighten up" the furnace by means of oxygen. The new furnace at Minneapolis is so equipped that the furnace process can be observed from the stock line to the iron notch. We have been taking gas samples at various elevations in the furnace to study combustibility of the fuel and the reducing power of the gas. If either of these is affected by removing inert nitrogen, the change can easily be measured.

Jan 11, 1924

By C. W. Beattie, R. L. Solter

ALUMINUM-KILLED, low carbon steel sheets are used extensively for severe deep drawing and other difficult forming operations. They usually, but not always, have a characteristic grain structure in which the grains are elongated both in the lengthwise and in the transverse direction. As described by Burns and McCabe,&apos; a typical grain in the plane of the sheet has its two axes in that plane from 1 Y2 to 4 times as long as the axis normal to the plane of the sheet. Rickett, Kalin, and MacKenzieZ have also reported on the recrystallization behavior of such steel. The contrast in grain structures of fully processed sheets of aluminum-killed and rimmed steel is illustrated by Figs. 1 and 2. The elongated grain structure of the aluminum-killed sheet is not developed on all heats or lots of this metal, and studies of the factors controlling and influencing its formation are reported in this paper. Jeffries and Archerb tate that unstrained grains are normally equiaxed, but exceptions are common. For example, if a metal containing a material mechanically obstructing grain growth is subjected to considerable working followed by thorough annealing, it may exhibit grains consistently elongated in the direction of working. Our experiments demonstrate that aluminum-killed, low carbon steel is such a metal, and that the substance mechanically obstructing grain growth is aluminum nitride. The effectiveness of aluminum nitride in inhibiting grain growth has been found to be influenced by the degree of cold reduction, the rate of heating in annealing, the thermal history of the sample before cold reduction, and the residual aluminum content. A correlation between grain shape and austenitic grain coarsening temperature also was indicated and additional experiments demonstrated that aluminum nitride is also the principal cause for the fine grain characteristic of aluminum-killed steels. Manufacture In conventional practice, aluminum-killed sheet steel is manufactured from a low carbon steel containing approximately 0.02 to 0.07 pct residual (HC1 soluble) Al. With the exception of certain samples containing greater or lesser amounts of aluminum, the steels used in these investigations were within the following composition range: C, 0.03 to 0.06 pct; Mn, 0.28 to 0.38; S, 0.017 to 0.032; Al, 0.03 to 0.06; P, <0.01; and Si, <0.01. Properly heated ingots are rolled to slabs about 4 in. thick. After surface conditioning, the slabs are reheated to about 2300°F and hot rolled continuouslv to strip about 1/10 in. thick. The strip rolling is completed at a temperature of 1550°F or higher, and the strip is coiled, usually at a temperature near the lower critical transformation. After cooling, the strip is pickled to remove oxide, cold reduced 40 to 70 pet to final thickness, then annealed to 1250° to 1350°F in 20 to 80 ton charges, the size of which results in slow heating and cooling rates. Effect of Cold Reduction According to Sachs and Van Horn,&apos; the deformations of the individual grains in rolling are similar to those of the total volume. Thus individual grains would elongate in rolling according to the amount of cold reduction imposed. This is true theoretically, but as cold reduction increases the individual grains tend to fragment, and measured grain elongations become less than theoretical. The amount of grain elongation may be described by a numerical rating based on grain counts made by the intercept method. Specimens are polished normal to the plane of the sheet, with the polished surface extending parallel to the rolling direction. After etching, grain intercepts are counted along a 50 mm line on a micrograph of suitable magnification. In random locations parallel to the plane of the sample 20 counts are made and 20 are made in the thickness direction of the sample the average count in the thickness direction divided by the average count parallel to the plane of the sample gives a numerical rating of the grain shape called grain elongation. For example, a grain elongation of 2.00 means that the average grain is twice as long as it is thick. The average of both counts may be converted to grains per sq mm by a nomograph relating intercept counts and grain count. By the same procedure the grain elongation in the plane of the sheet but transverse to the rolling direction may be determined, using transverse metallographic samples. A comparison of theoretical and measured grain elongation was obtained on an aluminum-killed

Jan 1, 1952

By G. F. Jr. Butterworth

THE metallographic structures most frequently encountered in rifle barrels, and which are illustrated by the accompanying photomicrographs, fall naturally into two groups, distinguished by the method used to produce in the stock a physical condition having the requisite properties. The first group consists &apos;of "rolled" barrels; that is, barrels subjected to hot working by rolling in or near the critical range. In the second group, the stock, which is smaller in diameter than the first, is upset to form the butt end and is then heat-treated by giving it a quench and a draw. These barrels will be referred to as "heat-treated" barrels. The structure of the rolled barrels resembles closely that of the same steel after annealing. There is the same network of excess ferrite outlining the grain boundaries, but the grains themselves are composed of sorbite rather than pearlite. The grain size is closely related to the rolling temperature. The critical-point curves of this grade of steel, which is approximately 0.50 to 0.60 per cent. of carbon and 1.00 to 1.30 per cent. of manganese, show a single very pronounced point between 1300° and 1350° F. (704° and 732° C.). Barrels rolled within this temperature range give an exceedingly fine grain, shown in Fig. 1. In fact, the grains may be so fine that, at a low magnification, they may be confused with the heat-treated structure discussed below, Fig. 6. A magnification of 500 diameters, however, will always resolve a rolled barrel into the characteristic structure, shown in Fig. 2. As the temperature is increased, the grains are found to be larger. If, on the other hand, the rolling temperature is below the critical range, the structure previous to rolling will not be obliterated, the only effect of rolling being to elongate the coarse sorbite grains in the direction of rolling, Fig. 3. This distortion is greatest at the muzzle. Heat-treated barrels are quenched in oil from above the critical range, which should give a martensitic structure, Fig. 4, but the presence of some troostite in the martensite is frequently noted when the quench has not been sufficiently drastic, Fig. 5. The structure brought about by the subsequent draw is not so striking, though quite as typical. It is sorbitic or sorbito-pearlitic, and under- a low magnification appears

Jan 7, 1919

By Arvid E. Anderson, Frank K. Cameron

The weathering of copper-bearing ores with the formation of a water soluble salt and the recovery of the metal by leaching and evaporation precipitation, are processes long known, which have at various times been utilized with more or less commercial success. It is commonly assumed that the technical principles involved are quite simple and their application to a particular case easy. If these assumptions were true, we should anticipate a long list of uniformly successful leaching operations, which is not the case, and one would be justified only in calling attention to either unique or peculiar features of any particular enterprise; whereas, in studying the problems of the recovery of copper from the old workings of the Ohio Copper Co. in the light of available descriptions of other leaching projects, we have not found the assistance hoped for to guide us to the best realization of our own opportunities. It appears desirable, therefore, to call attention to these guiding principles, together with a description of the facts of accomplishment. Justification lies in the fact that the leaching and precipitation of copper at the Ohio Copper Co. mine in Bingham Canyon, Utah, is successful. This success is measured by an average monthly production of 600,000 Ib. of copper at an average operating cost, to date, of 3.85 cents per pound at the company&apos;s workings, or 6.32 cents per pound after paying shipping and smelter charges on the finished copper. A total of 17,076,099 Ib. of copper had been shipped to the smelter from the beginning of operations, August, 1922, to April 1, 1925. Probably these results can be bettered with further study and realization of the factors involved and the devising of methods of meeting them. It is now an assured fact that the enterprise will have a relatively long and continuously profitable life and that its reserves will not, nor cannot, be suddenly and permanently depleted. It is particularly noteworthy that the financing of this enterprise has been entirely from its earnings. The few hundred dollars necessary for the first experiments and production were obtained by the sale of used, and no longer needed, equipment from a mill belonging to the company; and all funds since required throughout the growth and development of the enterprise, from a few troughs with a production of 2000

Jan 1, 1926

By A. R. Elsea, E. E. Fletcher

This paper describes a metallographic investigation of the influence of tungsten or molybdenum additions upon the transformation and precipitation reactions occurring in Co-rich Co-Cr alloys. It is shown that tungsten has little effect upon the a-ß transformation temperature range, while molybdenum tends to raise it. Both elements tend to promote the formation of ? phase, molybdenum being more potent in this respect than tungsten. HIGH temperature alloys, that is, alloys which have load-carrying ability at elevated temperatures, have been developed at an increasing rate during the past few years. This has resulted from the requirements in the design of modern aircraft engines. Although many alloys of this type are available, they have been developed on an empirical basis. Metallurgists do not have a clear understanding of the phases or structures that are responsible for these high temperature properties. In order to determine why these alloys possess this particular ability, a project was started at Battelle Memorial Institute with the object of learning more about the fundamental factors which promote high temperature strength in alloys. This study was to include a correlation of microstructure and the high temperature properties of Vitallium, an alloy which is widely used for high temperature service. Vitallium is a complex material both from the standpoint of composition and microstructure. Consequently, it was necessary to obtain informa- tion regarding the phase relationships in this alloy. The Co-Cr binary diagram was determined as the first phase of this investigation.&apos; A second paper described the effects of iron, nickel, or nitrogen on the reactions occurring in the Co-rich end of this system.&apos; The present paper covers a continuation of this investigation in which the effects of tungsten or molybdenum on the reactions occurring in Co-rich, Co-Cr-base alloys were determined. Preparation of &apos;rest Materials Two series of ternary Co-Cr-base alloys, representing Co-Cr ratios of 80:20 and 68:32 ( Cr x 100 =20 and 32 ) , were prepared containing ( Co + Cr = up to 6 pct W and up to 12 pct Mo. Melting stock consisted of electrolytic Co, electrolytic Cr, 99.9 pct pure W, and 99.9 pct pure Mo. Table I lists the chemical analyses of these materials. The melting furnace was a vertical porcelain tube

Jan 1, 1952

By W. M. Small

Austria.—Austria produced some 430 cisterns of 10,000 kg. each of crude oil of a 0.9428 sp. gr. during 1934. Gosting II well near Zis-tersdorf was placed on the pump in August and at the end of the year was still producing about three cisterns daily. This well is owned by the Erdöl-Produktionsgesellschaft while Gösting I is owned by Raky-Danubia. Only five wells were completed in the republic during the year. These accounted for 1783.5 meters of the 2225 meters drilled. The only producer completed was Gosting 11. At the close of the year, four rigs were in operation and one rigging up. At least 8 or 10 new wells are planned in Lower Austria for 1935. The European Gas & Electric Co. put its 6-km. gas line into operation in May and has sold 12,301,550 cu. m. of gas to the Vienna City Electric Works. A 2-km. pipe line was built from Gösting II to the railway loading rack near Zistersdorf. Hungary.—No oil or gas was produced except a small amount of gas trapped from flowing artesian wells. The Government completed and abandoned a 1500-m. hole at Tisztaberek in northeastern Hungary and is drilling at 967 m. near Bogáes, 120 km. northeast of Budapest. It is unofficially reported it plans to drill two new wells in 1935. The European Gas & Electric Co. has a rig up for a test at Mihalyi in Transdanubia. Czechoslovakia.—In Gbely (Egbell) there were produced 1283 cisterns of 10,000 kg. of 0.935 sp. gr. oil and a small amount of gas used for fuel. This field is operated by the Government; 17 shallow producing wells and three dry holes were drilled, with a total of 3351 m. of hole completed. In Hodonin (Goding) there were produced approximately 1300 cisterns of 10,000 kg. each of 0.91 sp. gr. oil and a small amount of gas used for fuel. The field is operated by the Apollo, which drilled four producing wells averaging 460 m. in depth, one small gas well of 550 m., one small gas well 260, and one dry hole 230 m. Two wells were deepened a total of 80 meters. The Government is drilling below 800 m. in a wildcat test in eastern Czechoslovakia near the Rumanian frontier.

Jan 1, 1935

By John A. Shelton

One of the heaviest burdens uselessly cast by our mineral land laws upon the holder of the title conveyed by a patent from the United States is due to the provision excepting known veins from land patented as placer. In many instances the expense of defending such titles from the assaults of the owners of lode locations made upon the theory that the veins so located were known to exist at the date of the placer application for patent has exceeded many times the value of the land in question. Neither the lapse of time, however long after the issuance of the patent. nor repeated adjudications by the courts serve to quiet such titles Or to prevent them from being questioned. In the passage of laws providing for the acquisition of title to the mineral lands of the United States, Congress provided that the title to known veins should not pass from the United States by a patent based upon a placer location. As construed by the courts, the law (Sec. 2333 R.S.U.S.) provides that the applicant for a patent upon a placer claim may, if any vein of sufficient value to justify the expenditure of money in its development is known by him to exist within the boundaries thereof, include in his patent application an application for patent upon the vein as a lode claim; and failure to do so is to be deemed a conclusive declaration that the applicant makes no claim to the vein nor to an area of surface ground extending for 25 ft. (7.6 m.) on each side of its middle or center. As to such vein and such area of enclosing surface ground under the circumstances stated, the title remains in the United States notwithstanding the issuance of a patent that purports to convey the entire surface of a described area and everything beneath it, excepting only the segments of veins the apices of which lie outside of such area. Such known veins with such area of enclosing surface ground are, of course, at any time, so long as they remain unlocated, subject to location and appropriation in the same manner as other. veins upon the public domain. The history of the operation of this law in one district will serve to illustrate its effect generally throughout the mining regions of the United States. In the Butte district, the mineral that first attracted the atten-

Jan 1, 1920

The eastern part of the state of Rhode Island on both sides of Narragansett Bay, including the island of Rhode Island, is underlaid with carboniferous rocks which carry veins of anthracite. This formation extends into the neighboring portion of Massachusetts, including the area from the state line, the towns of Mansfield, Brockton and Bridgewater,: and extending probably ten miles east of the latter two towns, to Middlesboro, and to Fall River. In Massachusetts the coal formation extends over nearly the whole of Bristol, and parts of Plymouth and Norfolk Counties. In Rhode Island and Massachusetts the area covered is about 400 square miles. In both states the exact limits of the coal measures cannot be determined on account of a thick layer of drift which overlays it. Along parts of Narragansett Bay, the coal measures outcrop in the cliffs on the west side of Rhode Island, and the presence of coal here seems to have been noted as early as 1760, and in 1768 a patent was granted to parties who "were about to dig after pit, coal or sea coal" at the back of the town of Providence. In 1807-08 Benjamin Silliman, later a geologist, visited some openings,&apos; and in 1808 a mine was opened near Portsmouth, in the northeast part of Rhode Island. Work was done here until about 1814 when the mine was abandoned. No anthracite had been used in New England at that time, all coal used came from Nova Scotia, Virginia or England, and was high volatile bituminous; neither experience nor the means of firing favored the use of the local fuel? This mine was again working in 1827, was again abandoned and operations were resumed in 1847. In 1837 a note in a magazine mentions, "the immense coal mine in Cumberland-about six miles from the city of Providence" as having a shaft 14 ft. in diameter and 80 ft. deep, that the horses then used for hoisting the coal were to be superseded by a steam engine and another shaft was to be sunk. With these improvements 30,000 to 50,000 tons were to be produced the following year at a cost of $1 per ton and a sales realization of $6.1 Hitchcock&apos;s report refers to a number of localities in both states where definite knowledge of coal existed. These are:

Jan 1, 1942

By John Shelton

ONE of the heaviest burdens uselessly cast by our mineral land laws upon the holder of the title conveyed by a patent from the United States is due to the provision excepting known veins from land patented as placer. In many instances the expense of defending such titles from the assaults of the owners of lode locations made upon the theory that the veins so located were known to exist at the date of the placer application for patent has exceeded many times the value of the land in question. Neither the lapse of time, however long after the issuance of the patent nor repeated adjudications by the courts serve to quiet such titles or to prevent them from being questioned. In the passage of laws providing for the acquisition of title to the mineral lands of the United States, Congress provided that the title to known veins should not pass from the United States by a patent based upon a placer location. As construed by the courts, the law (Sec. 2333 R.S.U.S.) provides that the applicant for a patent upon a placer claim may, if any vein of sufficient value to justify the expenditure of money in its development is known by him to exist within the boundaries thereof, include in his patent application an application for patent upon the vein as a lode claim; and failure to do so is to be deemed a conclusive declaration that the applicant makes no claim to the vein nor to an area of surface ground extending for 25 ft. (7.6 m.) on each side of its middle or center. As to such vein and, such area of enclosing surface ground under the circumstances stated, the title remains in, the United States notwithstanding the issuance of a patent that purports to convey the entire surface of a described area and everything beneath it, excepting only the segments of veins the apices of which lie outside of such area. Such known veins with such area of enclosing surface ground are, of course, at any time, so long as they remain unlocated, subject to location and appropriation in the same manner as other veins upon the public domain. The history of the operation of this law in one district will serve to illustrate its effect generally throughout the mining regions of the United States. In the Butte district, the mineral that first attracted the atten-

Jan 8, 1919

By A. H. Geisler, J. H. Keeler

Preferred orientations in rolled and annealed titanium sheets were determined by the Geiger counter spectrometer X-ray diffraction technique. Five annealing textures dependent upon the temperature range of annealing were found, and in order of increasing annealing temperature pendent upon the temperature range are: 1—a deformation like texture, 2—a rotated inorder a-recrystallization temperature texture, 3-a retained u-recrysraIlization texture, on annealing at lower temperatures of the ß-region, 4—a transformation texture based on recrystallized a and predicted by the Burgers&apos; relationship, and 5—a ,ß-cube texture. These results are examined in terms of current theories of recrystallization textures. UMEROUS investigators have described the tex- ture obtained by cold rolling the hexagonal metals, titanium, zirconium, and beryllium, which have c/a ratios less than that of ideal packing, 1.633. The basal planes are rotated out of the rolling plane, about the rolling direction, so that the basal poles are tilted toward the transverse direction as shown schematically in Fig. la. In all instances but one,&apos; it was also reported that the [1010] direction was parallel to the rolling direction (see Fig. lb). Hot rolling has been reported as causing a similar tilt of the basal poles in the transverse direction (see Fig. la) and causing the [1010] direction also to be parallel to the rolling direction as shown schematically in Fig. lb. Annealing after deformation does not appreciably change the tilt of the basal poles in the transverse direction." Beryllium2-7 continues to have the [1010] direction in the rolling direction after annealing, and similar observations for titanium and zirconium&apos; . have been reported for annealing at fairly low temperatures, again as in Fig. lb. At higher annealing temperatures, however, the recrystallized grains of titanium" and zirconium have an orientation such that the [1120] direction is approximately in the rolling direction, although the basal poles are still inclined in the transverse direction. Figs. la and lc show the resulting orientations schematically. This change in orientation has been described as a nominally ±30° rotation of the hexagonal crystallites about the basal poles of the cold rolled texture and is apparent from the results which are summarized in Table I for investigations with the X-ray diffraction technique employing film. The angles y, , and ß are indicated in Fig. 2 which represents the stereographic projection of (1070) poles for the mean orientation of a pole figure. Texture determinations for titanium using the Geiger counter spectrometer have provided similar results except that in some instances additional components of the texture were proposed, as shown by the summary of data in the upper half of Table 11. On the other hand, the spectrometer technique, when applied to zirconium,* has revealed a splitting Recently completed studies of the textures of annealed zirconium", show zirconium to possess textures very similar to those reported here for titanium. Therefore, much of this discussion will include zirconium by virtue of its close similarity to titanium in pref erred orientations. of the intense areas of the pole figure for samples annealed at 600°C. This splitting could be described by a 7" rotation of the tilt axis about the normal to the rolling plane. Such a splitting for the annealed texture relative to the cold rolled texture was not observed in other determinations for either zirconium or titanium using the less sensitive film X-ray methoe and makes the relationship between the two types of texture more complex than the simple rotation about the (0001) pole based on film work. The more precise investigations on zirconium permit the descriptions in the lower part of Table 11, which show that the texture depends quantitatively on the temperature of annealing. When zirconium is annealed at temperatures up to 400°C, the texture is similar to the cold rolled texture, while annealing in the range 500" to 900°C produces a texture which is only approximately described as [11%] in the rolling direction. More precisely described results for zirconium show that the two types of splitting ( 1—about an axis in the rolling plane through an angle given in the second column in Table II and 2—about the normal to the rolling plane through an angle given in the third column of Table 11) depend on annealing temperature. The [1120 is the rolling direction only when the annealing temperature is in the vicinity of 900°C

Jan 1, 1957

By R. D. Carnahan, J. E. White

ThE use of strain gages in the measurement of microplastic behavior of materials is well-known.&apos;-3 Recently it has been suggested that similar techniques might be useful for determining stress relaation. It is the purpose of this report to comment on the use of strain gages in the measurement of strains in the vicinity of 10"6. We will also discuss observations of an anomalous anelastic behavior apparently associated with small temperature changes, which accompanies the unload portion of a load-unload microstrain test. The key to successful strain determinations at levels below 1 pin. per in. is a good gage-mounting technique and either precise ambient temperature control or a set of matched temperature-compensated gages. The importance of good mounting cannot be overemphasized, for example, as in the use of Eastman 910 contact cement. If the cement layer is not sufficiently thin and properly hardened, it is possible to observe anomalous negative stresses when small loads are removed, which relax back to zero in an orderly way with time. Such anomalous behavior, thought to be due to gage bonding, has been reported in microstrain experiments by Thomas and verbach&apos; who observed a negative strain of -3 X lo-&apos; upon unloading. This kind of behavior severely limits the over-all strain sensitivity which can be achieved in such tests. The relaxation of a small positive strain subsequent to unloading in a load-unload experiment is quite normal, however, and is to be expected. The occurrence of an apparent negative strain is also encountered in those instances where the elasticity of the bonding cement is exceeded—for example 0.5 pct or 5000 pin. for cured Eastman 910. An elastic strain of this magnitude can be encountered during load-unload type testing particularly in higher-strength materials (-150,000 yield strength). During the course of microplasticity studies on pure nickel and nickel alloys,&apos; the authors have made the following observation. In a four-point bending test, two active gages are mounted one on each side of the beam as arms R1 and R z of a conventional strain-gage bridge circuit shown in Fig. l(a). This technique provides two advantages: the sensitivity is doubled because R1 and Rz experience opposite strains and temperature compensation is provided automatically because any ambient temperature change would cause both gages to see a strain of like sign whose signals would cancel in the circuit.

Jan 1, 1964

By K. J. Rosengren

INTRODUCTION Mount Isa Mines Limited operates a major mining complex at Mount Isa in northwest Queensland, Australia. The location is arid and remote, some 600 miles distant from the nearest port of Townsville on the eastern coast (Fig. I). Current mine production is 6 million long tons per annum comprising 3.8 million tons of copper ore and 2.2 million tons of silver-lead-zinc ore. Copper ore production is scheduled to increase to 5.8 million long tons per annum by 1973 and a new silver-lead-zinc mine is being developed at Hilton, 13 miles north of Mount Isa. The Mount Isa and Hilton orebodies occur in a single stratigraphic member, termed the Urquhart Shale. This shale is conformable with several other sedimentary formations striking north-south and dipping approximately 65º west. The silver-lead-zinc orebodies occur in bands conformable with the shale bedding and tend to be of tabular shape, varying in width from a few feet to nearly 200 ft. The copper orebodies occur in breccia bodies, locally known as "silica-dolomite", within the Urquhart Shale and tend to be more irregular and massive with widths up to several hundred feet. The detailed geology is described by Bennett (1 2). At present, production comes almost entirely from underground operations with only about 25,000 tons per year of carbonate ore from open pit operations. The mining method used in the copper orebodies is sublevel open stoping with pillar recovery by pillar blast before stope filling or by sublevel caving after stope filling. A large primary sublevel caving operation was also carried out until recently in one of the orebodies. The wider lead orebodies are mined by sublevel open stoping, with or without pillar recovery, while cut and fill stoping is used in the narrower orebodies. Details of the mining methods are given by Davies (3). The company&apos;s interest in open pit mining stems from a large open pit which was mined out in 1965 and a further large open pit planned for future production. In addition, the company is currently evaluating several large ore deposits in Australia and New Guinea. All of these orebodies would be mined by open pit methods and rock mechanics studies of slope stability are now a standard feature of all open pit evaluations.

Jan 1, 1972

By A. Sutulov

The segregation process, an alternative to benefi-ciation of oxidized and mixed sulfide-oxide copper ores, is studied here with particular emphasis placed on time, temperature, and coke and salt percentage factors. The results show that in a segregated charge, the copper assay of the coarsest fractions normally is of the same order as the copper assay of the tails obtained from grinding and flotation of the same charge. This observation suggests the possibility of limiting or even eliminating the grinding step from the flowsheet of a segregation plant. The segregation process, which offers an alternative to beneficiation of oxidized and mixed sulfide-oxide copper ores, was discovered in 1923 by Moulden and Taplin1,2 who were attempting to apply the Perkins process3&apos;4 to a Chilean ore from the Sagasca mine. After a number of investigations and pilot plant tests,&apos;-&apos; the segregation process became a successful industrial operation.&apos;r9 The process aroused considerable interest in Chile because of the existance of large reserves of oxidized copper minerals which could not be treated by conventional hydrometallurgical methods because of the high consumption and prohibitive cost of sulfuric acid. During the last two years, the Mineral Dressing Dept. of the Institute de Investigaciones Tecnology cas of University of concepci6n (Chile) has carried out a test program on 23 different ore samples representative of the national territory. These tests were carried out on a semi-continuous and batch scale with a rotary, automatically controlled and gas-fired furnace (supplied by Bartlett and Snow, Fig. 1). The results of these tests indicate that out of the 23 samples 20 can be successfully treated by this process with recoveries of copper ranging from 85 to 95%.10,11 The purpose of this paper is to treat some specific problems related to the segregation process. TIME AND TEMPERATURE FACTORS Time and temperature of calcination play an important role in the segregation process. When moderate salt and coke conditions were maintained (each of reagents was added in the quantity of 1 — % wt), systematic testing easily demonstrated the influence of these two factors on segregation and flotation recovery. The pertinent results are summarized in Fig. 2. To determine what specific changes the segregation process made on the ore, the samples, segregated at 700°C for different periods of time and under standard conditions, were granulometrically analysed and

Jan 1, 1963

By Oscar A. Glaeser

THE mine and plant of the United Verde Copper Co., located in Yav-api County, at Jerome, Arizona, have been described in various technical publications and, therefore, a brief outline of its essential features will suffice. The orebodies are of the schist replacement type, the main sulfide mass being a large lens-shaped body approximately 7 acres in cross-sectional area. In general, the mineralization is found along the iron-schist contact, with the orebodies extending about 1000 ft. along this contact and varying from a few feet to 250 ft. in width. The mine is located on a mountain slope and has openings into it on three horizons, as follows: 1. Raises and ore passes open vertically into the shovel pit. These extend down to the 1000-ft. level, where they terminate as loading bins in the Hopewell adit. The main fan intake air shaft, which also extends vertically down to the 1000-ft. level, has its surface opening on the hillside at the extreme north end of the shovel pit, and the main mine air return exhausts through a raise at the extreme south end of the shovel pit. 2. The 500-ft. level adit. 3. The Hopewell adit on the 1000-ft. level. The mine has a vertical downward extent of 2000 ft. below the 1000-ft. level. Underground operations are carried on through two main shafts, both of which are wholly underground. Shaft 5 is the ore-hoisting shaft. It has three compartments and extends from the 800 to the 3150-ft. level. Shaft 6 is the service shaft, and is used for lowering and hoisting men and material. It has a large cage compartment and three smaller compartments for counterweights, ladderway, and pipe and power lines. This shaft extends from the 500 to the 2550-ft. level, and is now being extended to the 3000-ft. level. An air shaft for the downward movement of fresh air from the fan has been provided, and extends to the 2550-ft. level at this time. Work has been started to extend this air shaft to the 3000-ft. level. A return airway for vitiated mine air, in the form of raises and short connecting drifts, extends downward to the 2100-ft. level. The underground mining operations extend from the 300 to the 3000-ft. level. There are about 45 stopes in active operation on the 17 levels

Jan 1, 1929

By John K. Berry

The handling and disposal of mine water is a much larger problem than is apparent at first glance. Many more tons of water are removed from underground coal mines in the United States each year than tons of coal. In the old anthracite region of Pennsylvania the average was around 36 tons of water for each ton of coal produced, while bituminous mines average about 5 or 6 tons. Water encountered in the mines may come from several different sources. In mines with light cover and without a firm solid roof, rain may seep directly into the workings. This is also true of deeper mines where pillar falls have broken the roof to the surface. The top under creek beds is generally faulty and broken and water comes through the roof at this point. Deeper mines are frequently overlain by water-bearing strata and pillar breaks and faulty top can admit water, while places running to the dip often accumulate water which comes up through the bottom. In all cases, except where passing under a year-round stream, the amount of water made is usually pretty closely connected with the weather-more water during the rainy season, less in the dry, although the deeper a mine is, the longer it is before changes in rainfall are felt. Another source of water, not connected with seasonal changes, is old water, accumulated over a period of time in abandoned workings of the mine, or from flooded adjacent mines. Here the water filters through the coal, the parting, or comes up through cracks in the bottom. Similarly, core holes, drilled to prospect the property, can be a source of unexpected water and modern safety requirements for dust-allaying water at the working faces can turn a pleasant working area into a soggy mess over the weekend if the system is not properly maintained and operated. Why water must be disposed is obvious. If allowed to accumulate, sooner or later the mine will fill up, or at least it will become "roofed" in low places, blocking ventilation and traffic. But it must also be controlled long before it reaches this stage. Water standing in the working faces is unpleasant for the men who have to work there and also cuts down on the amount of work they can do, as they must watch where they step all the time. It is especially unpleasant in low coal.

Jan 1, 1973

By John Campbell

An approximate theoretical model is proposed to quantitatively predict freezing ranges Tf and hydrostatic tensions P developed within solidifying binary alloys, allowing for a certain amount of diffusion of solute in the solid during solidification. The maxima in ATf and AP as functions of composition are shorn to occur at smaller solute concentrations than would be expected from the equilibrium diagram, and are found to correspond closely to experimentally observed maxima in microporosity. THE freezing range of simple binary alloys appears to have been little studied, except for certain indirect observations on the defects, particularly microporosity and hot tearing, arising in long freezing range materials. Two theories relating to the freezing range of alloys and its effect upon porosity are reasonably well established, and appear to have been held in isolation from each other: a) From purely equilibrium considerations early researchers expected that an increase in solute content of an alloy should increase the freezing range (defined here as the equilibrium freezing range ?Tf = Tl-Ts where TL and Ts are the liquidus and solidus temperatures, respectively) and thereby increase the width of the pasty zone for a given set of conditions. This in turn should increase the difficulty of feeding the residual liquid through the dendrite mesh to compensate for the contraction on solidification, and consequently tend to increase the observed amount of porosity. From qualitative observations on steels Czikel1 reports an increase in porosity with increasing carbon content up to 0.46 pct C. More careful measurements by Whittenberger and Rhines2 on fourteen different alloy systems showed an approximately linear relation between ?Tf and pct porosity (although unfortunately the precise experimental data is not given). b) Conversely however, other authors3"5 propose that porosity is reduced by the presence of increased amounts of eutectic present at the final solidification temperature. Lees7 and Bochvar6 claim that the hot tearing of alloys is similarly reduced. Scheuer8 has put forward a theory to explain this effect, Fig. 1. The argument is basically that solidification progresses on a plane front through a relatively open dendrite network and is thus (the argument is not developed more explicitly) easier to feed. One would expect effect a) to operate at low solute contents, and b) to be important at higher solute contents, so that at some critical composition a max-

Jan 1, 1970