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By Paul Billingsley

When I was an undergraduate at the Columbia School of Mines, the mining curriculum was subdivided into two major branches's known respectively as the Metallurgical and the Geological Options, which diverged rather widely as the course progressed. When I duly elected the Geological Option, I believed, I am sure, that this divergence would continue throughout the years. The facts have proved otherwise. The mining industry is a closely knit entity in which the search for its raw matcrials, called mining geology, cannot be separated from the conversion of these raw materials into marketable form, called metallurgy. The mining geologist searches for materials which the metallurgist can utilize, and only such; and whenever an advance in metallurgy opens the gates for new matcrials, the geologist's problem is correspondingly modified. No better instance of this relationship can be given than that seen in the Salt Lake region in recent years. Our mineral industry here is of long standing. The three principal tributary districts, Bingham, Park City and Tintic, were discovered in the 1860's and have been vigorously and intelligently developed for many decades. Their production has made the Salt Lake valley one of the world's great smelting centers. The maintenance of this industry has for years depended upon the continual development of new orebodies to take the place of those being extracted. Intensive exploration in the old districts has been supplemented by prospecting in outlying districts of lesser prominence. Many new orebodies have been discovered, such as those of the Daly West, Silver King, and Judge mines in Park City, the Utah Apex in Bingham, and the Sioux, Colorado Chief Consolidated and Tintic Standard in Tintic. New mines in other districts have been discovered also, but without affecting the dominánce of the three major districts. In all cases discoveries, to be of value, had to be of ore amenable to treatment in the available metallurgical plants. This meant that, for the most part, zincy ores, both oxide and sulfide, must remain untouched, and also that ores high in iron and ores high in silica had a fictitious value, either high or low, set by the balance of these

Jan 1, 1928

By Paul Billingsley

WHEN I was an undergraduate at the Columbia School of Mines, the mining curriculum was subdivided into two major branches's known respectively as the Metallurgical and the Geological Options, which diverged rather widely as the course progressed. When I duly elected the Geological Option, I believed, I am sure, that this divergence would continue throughout the years. The facts have proved otherwise. The mining industry is a closely knit entity in which the search for its raw materials, called mining geology, cannot be separated from the conversion of these raw materials into marketable form, called metallurgy. The mining geologist searches for materials which the metallurgist can utilize, and only such; and whenever an advance in metallurgy opens the gates for new materials, the geologist's problem is correspondingly modified. No better instance of this relationship can be given than that seen in the Salt Lake region in recent years. Our mineral industry here is of long standing. The three principal tributary districts, Bingham, Park City and Tintic, were discovered in the 1860's and have been vigorously and intelligently developed for many decades. Their production has made the Salt Lake valley one of the world's great smelting centers. The maintenance of this industry has for years depended upon the continual development of new orebodies to take the place of those being extracted. Intensive exploration in the old districts has been supplemented by prospecting in outlying districts of lesser prominence. . Many new orebodies have been discovered, such as those of the Daly West, Silver King, and Judge mines in Park City, the Utah Apex in Bingham, and the Sioux, Colorado Chief Consolidated and Tintic Standard in Tintic. New mines in other districts have been discovered also, but without affecting the dominance of the three major districts. In all cases discoveries, to be of value, had to be of ore amenable to treatment in the available metallurgical plants. This meant that, for the most part, zincy ores, both oxide and sulfide, must remain untouched, and also that ores high in iron and ores high in silica had a fictitious value, either high or low, set by the balance of these

Jan 1, 1928

By AIME AIME

AMERICAN participation in the World Engineering Congress in Japan will be generous. Nearly seventy papers have been prepared and for- warded for printing and the A. I. M. E. is well represented in the list. At our San Francisco meeting four of these will be briefly reviewed by the authors for the benefit of those who are unable to go on to Tokyo. They constitute a group dealing with the present economic status as seen by engineers of the world's iron, coal, petroleum and non-ferrous metals. Messrs. Leith, Smith and Tryon, Requa, and Probert have written papers that constitute a notable series. Messrs. Jeffries, Sweetser and Kinney, and other Institute members have written papers dealing more closely with technologic progress. The latest list of delegates and members is printed below, names of A. I. M. E. members being set in italics.

Jan 1, 1929

By Max Roesler

Page I. Introduction........................... 78 Location.......................... 78 Scope of Work and Acknowledgments.............. 79 History and Mining...................... 80 I1. Topography and its Interpretation................. 80 III. Petrology............................ 82 Sedimentary Rocks...................... 82 Description....................... 82 Age.......................... 84 Igneous Rocks........................ 85 Diabasic Rocks..................... 86 Dioritic Rocks...................... 87 Granitic Rocks...................... 88 Later Dike Rocks.................... 88 IV. Areal Geology.......................... 88 Rock Types Found in the District............... 88 Distribution of the Various Rock Types............. 89 Surface Distribution................... 89 Vertical Distribution................... 90 Causes of Present Areal and Vertical Distribution of the Various Rock Types..................... 91 Faulting...................... 91 Magmatic Differenti~tion............... 91 Tilting........................ 95 Erosion....................... 96 V. General Description of Ore Deposits................ 96 Nature of Ore ........................ 96 Shap~ and Size of Orebodies.................. 96 Geologic Position....................... 97 Mineralogy......................... 98 Distribution....................... 98 Interpretation...................... 99 Superficial Alteration................... 102 VI. Genesis of the Ore Deposits.................... 104 Previous Theories...................... 104 J. P. Kimball...................... 104

Jan 1, 1917

THERE have been two important accomplishments of the Truman administration; the Hoover Commission report on inefficiency and waste in government and the report of the Paley Commission on the natural resources of the United States. Both reports are in the interest of the American people and should transcend the boundaries of political parties. Both reports are starting points for the formulation of policies which must be continuously revised to meet changing conditions. Regardless of the outcome of the election the principles embodied in these two great documents must be kept alive. The Paley report is right in our own bailiwick of mineral raw materials and it behooves us to study it carefully as our responsibility to posterity. To those in the mining industry who have limited their field of observation to moving rock or to metal prices it may come as a surprise that our production of such staples as copper, lead, and zinc has fallen behind increased requirements to the point that substantial tonnages must be imported. Iron ore is next on the list and everybody knows that such metals as tin, tungsten, chromium, manganese, nickel, and cobalt are imported almost exclusively. The crisis in raw materials pointed up by the Paley report has been reported annually by Elmer Pehrson and others to small gatherings at the Mineral Economics Division sessions at the Annual Meeting for as long as we can remember. In September 1949, the United Nations Economic and Social Council held an international resource conference at Lake Success which disclosed these same grave conclusions: - Consumption of raw materials is multiplying at an alarming rate, faster than discoveries or replacements are being made. - Production has been wasteful and utilization lavishly beyond enginee¬ing and practical requirements. - Industrialized nations are depleted and many raw materials consumed by industry are not found in the industrialized countries. - Nations formerly exporters of raw materials are increasingly building their own consuming industries. - Political forces in the world are limiting access to raw materials. The Paley Commission selecting the quarter century, 1950 to 1975, to project raw material requirements for the United States, pointed out obstacles to meeting these requirements, and made recommendations for procurement. It is not important that we disagree that cobalt consumption will reach 344 pct of present, or fluorspar 187 pct when iron and ferroalloys are only expected to increase 75 pct. What is important it that the fabulous appetite of the United States for mineral raw materials has consumed more since World War I than was consumed by the entire world in all recorded history prior to 1914. And, unless the people of the United States are satisfied to remain at their present standard of living (which is unthinkable) this consumption is correctly plotted by the Paley Commission as continuing to expand. If the U. S. is to continue on a course of progress, it must procure raw materials wherever it can at the lowest possible cost. Natural resources are clearly an area in which the broadest cooperation between industry and government must exist to achieve efficient exploitation, economic consumption, and expansion of sources of supply. The message of the Paley report requires action comparable to that of the North Atlantic Pact. Its implication is as significant as military preparedness. It is a world problem. It is a mining engineering problem. Don't let it die!

Jan 1, 1952

By R. A. Swalin, B. W. Roberts

ONSIDERABLE controversy has centered about the existence of an order-disorder transformation in alloys in the composition vicinity of 75 atomic pct Ni and 25 atomic pct Cr. All the evidence to date for such a transformation is of a rather indirect nature, since direct X-ray confirmation is difficult to obtain as a result of the small difference in X-ray scattering factors between nickel and chromium. As a result, superlattice lines would be very faint if present. Several investigators1-5 have observed anomalies in the electrical resistivity vs temperature curves of alloys in the vicinity of 25 atomic pct Cr. The observed change is characterized by a rather broad resistivity peak at about 540°C. A discontinuous drop in resistivity is normally associated with ordering. However, Taylor and Hin-ton4 have rationalized that the discrepancy could conceivably be caused by changes in the Brillouin zones upon ordering. The same investigators measured the specific heat as a function of temperature and have also observed anomalies in the vicinity of 540°C. Nordheim and Grant5 have proposed, because of the absence of superlattice lines and the absence of a discontinuity in the resistivity vs temperature curve, that long-range order is improbable and that the results could be better explained by short-range ordering. To date, however, the question has not been resolved satisfactorily. Neutron diffraction techniques provide a method for partially resolving the question since nickel and chromium have considerably different atomic scattering factors in the case of neutrons and, therefore, superlattice peaks, if ordering occurs, should be readily discernable. The results of a neutron diffraction investigation* coupled with a dilatometric in- vestigation are reported here. An alloy containing 28.0 atomic pct Cr was prepared from carbonyl nickel and electrolytic chromium in the form of a 1-in. diam x 10-in. ingot. Melting was done in an alumina crucible and casting in a graphite mold. The ingot was homogenized at 1250°C for seven days, after which a 5-in. long piece was cut into shavings in order to obtain a suitable neutron diffraction sample. Hardness samples and samples suitable for dilatometric analysis (% in. diam x 2 in.) were prepared from the remainlng piece. The neutron diffraction sample, along with a hardness sample, was annealed at 501°C for seven days, at which time the temperature was lowered to 479°C and held at this temperature for twenty-four more days. The hardness was observed to increase from 133 to 147 Vhn during the course of the annealing treatment, in qualitative agreement with Nordheim and Grant." Neutron diffraction traces taken at room temperature and at 42 °K are shown in Fig. 1. The insert shows the trace taken at room temperature with short counting times and thus only fair statistical accuracy. No evidence for superstructure reflections of Cu3Au-type ordering is observed. The statistical accuracy of the 4.2°K trace was improved by using longer counting periods. Several weak intensities are observed at small angles, including an aluminum reflection from the cryostat assembly and a very

Jan 1, 1958

By J. F. K. Brown

ANTHRACITE in 1943, in common with the coal industry as a whole, passed through a year of wage negotiations that seemed endless. In the early months discussion of the United Mine Workers' demands was taken up and carried on continuously until May, finally reaching an impasse when the Union refused to continue at work, while submitting their demands to the War Labor Board. Thus a strike threatened, averted by the Federal Government taking over the industry, effective May 1, by order of the President. An office of the Bureau of Mines was established in Wilkes-Barre under the direction of J. J. Forbes, Mineral Production Security Division, as regional manager, who conducted operations until September, 1943, when the collieries were turned back to the operators. But the miners did not agree with the War Labor Board's award rendered in the fall, resulting in a recurrence of the previously threatened strike. again averted by Government control. In addition to the major upsets, a number of individual suspensions occurred at various mines. In spite of these drawbacks, to which might be added the difficulty of obtaining equipment and the scarcity of man power, the industry by November was only little less than a million tons short of the previous year. and in all probability, finally produced but little less than in 1942. This little less. however, was greatly missed in the market.

Jan 1, 1944

By J. Blodget Britton

IN the Journal of the Franklin Institute for May, 1870, there is published a description of a Colorimeter, together with a modification of the method proposed by Professor Eggertz, for determining combined carbon in iron and steel. An instrument of the kind there described, but of a little higher range, though in other respects not differing materially from the one originally made and used in the Iron-Masters' Laboratory, I now submit to your inspection ; and I propose, also, to make some determinations with it for the purpose of showing how quickly they may be made, and enabling you to form some judgment of what reliance can be placed in the results. Professor Eggertz proposed only a single standard, and the solution to be tested should be diluted to exactly correspond in color with that of the standard, and the per cent. of carbon calculated after carefully noting and making allowance for the measures of water used in diluting. In practice, difficulty was found in bringing the color of the normal solution down to the exact shade of the standard ; also other difficulties were met with in conducting the process, causing delay and interfering with the accuracy of the results. To materially overcome these, and after numerous attempts, an instrument such as is now before you suggested itself to me; and also I concluded to use a larger quantity of metal than directed by Eggertz, and, in addition, to filter the solution from its insoluble matter before making the comparison ; and, more recently, to use an acid of just such strength as would completely dissolve the metal without the application of heat. Experimenting with these changes from the original method I obtained reasonably good results. The instrument, you will observe, consists of a series of tubes, sixteen in number, two and a half inches long, and about half an inch in diameter, standing upright, and securely fastened in a light, portable, walnut-wood frame, but separated one from the other so as to allow just sufficient space between to place for comparison the tube containing the solution to be tested. The tubes are filled with

Jan 1, 1873

By John Birkinbine

In the preparation of the paper upon " The Operation of Warwick Furnace, Pennsylvania, from August 27, 1880, to September 1,1885," presented at the Pittsburgh meeting, I purposely refrained from offering theories to explain the peculiarities of furnace operation, on the ground that it was better for those actively engaged in blast-furnace management to present records of operations, than for one more directly interested in blast-furnace engineering and construction to venture upon the sea of speculation as to causes. The manager of an iron-works naturally feels that he knows as much about his particular furnace or furnaces as any one else, and as Mr. Cook, after his close attention to and study of the Warwick furnace, was at that time unwilling to present theories, I felt a disinclination to assume more acumen than the manager.

Jan 1, 1887

By Raphael G. Kazmann

Is electricity from nuclear-fueled power plants a partial solution to the energy shortage? According to various public and private institutions, the answer is an emphatic "yes." According to various other groups, the answer is an equally emphatic "no." I believe that a true and scientifically valid "yes" or "no" answer at this stage is premature because of conflicting claims and inadequate data regarding these two fundamental aspects: (a) the duty of uranium, i.e., the actual number of kilowatt-hours that can be generated from a ton of natural uranium through the use of light water reactors; and (b) the availability of uranium in the US to meet the lifetime requirements of the reactors scheduled for construction in the 1975-1985 period, as well as to supply the requirements of those reactors now in operation.

Jan 8, 1975

By R. T. O’Brien, J. M. W. Mackenzie

A microelectrophoresis technique has been used to measure the zeta potential of quartz over a range of pH and Ni (11) and Co (Ilj concentrations. Results have been discussed in terms of adsorption of Ni (11) and Co (11) cations and hydroxide precipitates. Possible relationships between the experimental results and the formation of lateritic nickel deposits have been discussed. The adsorption of metallic cations to the surface of silicate minerals is of significance in many industrial and natural processes. In an earlier publication,' the adsorption of Fe (111) to the quartz surface, a phenomenon of importance in flotation, was studied qualitatively using microelectrophoresis techniques. This paper reports the extension of this work to an investigation of the adsorption from aqueous solution of Co (11) and Ni (11) to the quartz surface. The adsorption of these metals was of interest for two reasons; firstly, the importance of such an adsorption process in the formation of nickel deposits by the lateritization of nickeliferous rocks, and secondly, the comparison of electrophoresis data for these metals, whose hydroxides precipitate in the pH range 7-8, with similar data for Fe (111) where the hydroxide first precipitates at pH 2.8. The development of laterites is essentially a near-surface geological process involving vertical and, in part, horizontal redistribution of elements derived from rock-forming minerals. This redistribution of elements leads to the formation of layers within the lateritic profile which are enriched in one or more of these elements and, depending on the nature of the original rocks, continued lateritization may give rise to iron ores, bauxites or nickeliferous laterites. The mechanisms discussed in this paper deal with the last mentioned type of deposit although the considered factors are applicable to laterites in general. Nickeliferous laterites are derived from basic and ultrabasic rocks containing ferro-magnesian silicates. These rocks may be partly or wholly converted to serpentinites. Besides their high Mg, Si and Fe contents, they also contain small amounts of Mn, Al, Cr, Ni, Co, Cu and Zn. The nickel content is usually near to 0.2-0.3%, but for economic use this must be increased during lateritization to over 1% and preferably over 2%. The zone of nickel enrichment is usually at some depth within the lateritic profile. Unpublished work by Mr. O'Brien on nickel-bearing laterites in eastern Australia indicated four visually different types of material which were separated from crushed samples under a stereo-microscope. Although chemical analyses indicated that all four types of fragments contained 2-4% nickel and smaller amounts of cobalt, X-ray diffraction and optical studies revealed only quartz, hematite and chromite as well as, in one of the types, a serpentine mineral. No distinct, nickeliferous minerals were detected. Furthermore, it was possible to extract some 60% of the nickel content of the laterites with cold 0.5N hydrochloric acid. It was therefore postulated that much of the contained nickel was present as amorphous, adsorbed material. In considering this fact, as well as the problem of the actual method of transfer and fixation of elements within the lateritic profile, it was further postulated that the transfer of these elements probably took place partly as solutions and partly as colloids and that the fixation of these was caused by adsorption and flocculation. The existence of nickel in solution in water draining from serpentinites has been confirmed by Smurov.2 Although we have no evidence for the transportation of nickel in the colloidal state, it is well accepted that colloids are important in the formation of laterites. Previous work by Mr. Mackenzie' has already indicated that iron may be adsorbed on quartz under conditions which could be expected in a lateritic profile, but no information was available for nickel or cobalt. Although adsorption possibly also takes place on minerals other than quartz, the latter is significant because silica is an important constituent of the silicate parent rocks. During lateritization, it is released to form free quartz and it is likely that it is initially extremely fine-grained. This would provide abundant opportunities for adsorption and it was de-

Jan 1, 1970

By Pierre de P. Ricketts

Having had occasion while in Europe during the past summer to visit some of the foreign mints and assay offices connected with the same, I thought a brief description of the general process of coining employed, and such items connected with assaying as were new, might prove interesting to the Institute. The principal foreign mints are: the Royal Mint, London; and the mints in Paris, Brussels, Utrecht, Berlin, Vienna, Copenhagen, St. Petersburg, Stockholm, Madrid, Milan, Rome, and Constantinople. My time only permitted my visiting a few of the principal and largest given in the list, and for a description of the remainder I am indebted to the kindness of Mr. James M. Napier, who in company with the deputy master, and chemist of the Royal Mint, made a complete inspection of all the European Mints in 1870.

By L. D. Lash, J. R. Ross

Discovery of scandium in the Vitro solvent extraction plant for uranium led to commercial recovery of the byproduct. Micro amounts of scandium were extracted with uranium by dodecyl phosphoric acid, but failed to follow ura-niuminto the hydrochloric acid strip solution and were eventually concentrated in the organic extractant. A fluoride strip system was developed to recover scandium from the solvent in concentrated form. High purity scandium oxide was then prepared in multi-pound lots by chemical separation techniques. The plant recovery operation, final product purification, and analytical procedures are described. Scandium is a pseudo-rare earth which is truly rare and expensive. It has special properties which may make it desirable even at the present price of $2750 per lb. Recently the price was lowered from $5000 per Ib which had prevailed since 1952, and it is anticipated that usage will be stimulated because of the lowered price. This metallic element is distributed widely in trace amounts in the rocks of the earth's crust. In addition to micro-amounts found in most uranium ores, concentrations of 50 to 100 ppm have been found in Colorado ferberite ore, lateritic nickel ore, heavy sandstone from Utah, Wyoming, and New Mexico, and various zircon sands and monazites from the western part of the U. S. Scandium has been found as an essential constituent of very few minerals, the most important being thortveitite, a scandium silicate. At the present time, this mineral commands a price more than twice that of gold. Chemically, scandium is in group 3A of the periodic table. It is closely associated with yttrium and the rare earths which it strongly resembles in its reactions. It has a valence of three and will form an insoluble hydroxide, fluoride, or oxalate under proper conditions, similar to the rare earths. Eight years before its discovery, scandium was predicted by Mendeleef who ascribed his eka-boron with properties nearly identical to the actual properties of scandium. Its position as the element with Atomic No. 21 and Atomic Weight 44.96 places it between calcium and titanium in Period 4 of the chart. The successful commercial application of scandium must depend on unique properties to justify use of this high cost substance. Greater consumption would allow additional price reductions, but scan- dium will remain a relatively high-priced commodity because of its inherent scarcity. Research reportedly has been oriented toward use of scandium as an agent to achieve high-temperature, low-density alloys with magnesium and tantalum.' Also, the U.S. Air Force sponsored a project for production of research amounts of pure scandium metal.' The oxide has been used experimentally in electronics, ceramics, and metallurgy. The various aspects of scandium are well covered in recent publications.s-5 CONCENTRATE RECOVERY Small amounts of scandium exist in uranium ores and are dissolved during an acid leach yielding up to 0.001 gpl Sc2O9. When Vitro converted their uranium plant from phosphate precipitation to solvent extraction: scandium was found to follow the uranium into the dodecyl phosphoric acid solvent (DDPA). However, scandium did not strip with uranium from the DDPA in hydrochloric acid, but remained in the solvent. Therefore, a concentration of scandium built up in the organic phase. Residues from the solvent were spectrographed by the U.S. Bureau of Mines and found to contain scandium. As a result of this discovery, provisions were made in the plant for recovery of scandium-bearing concentrates. Solvent extraction of uranium was added to a conventional acid leach process in a typical installation? The ore was crushed and ground, and then leached with dilute sulfuric acid. Addition of an oxidant such as sodium chlorate insured conversion of uranium minerals to a soluble form. At this point, the slurry was chemically reduced by a sulfide, such as sodium hydrosulfide, to remove substances such as ferric iron and molybdenum which were partially extracted by the solvent. The solids-liquid separation was accomplished by a four-stage counter cur rent decantation (CCD) thickener circuit. The uranium was extracted from pregnant liquor with 0.1M DDPA in kerosene and stripped with ION

Jan 1, 1961

By D. E. Swets, R. C. Frank

It is well known that hydrogen is introduced into iron or steel as a result of many chemical processes (acid pickling, electrolytic cleaning, plating, etc.). One of the reactions that has been of recent interest1 is the reaction between an iron surface and water vapor. It was shown a few years ago2-4 that hydrogen can be introduced into steel at an accelerated rate during abrasion as a result of this reaction. Grun-berg and Scott have also observed that water in mineral oil lubricants increases pitting failure in ball bearings5 and they have suggested that hydrogen from the water is the primary cause of this effect.' In this laboratory, the question was raised as to whether or not hydrogen is also introduced into the metal surface of a bearing as a result of the decomposition of the hydrocarbon lubricant itself, and an experiment was performed to try to find a satisfactory answer. All steel parts contain some residual hydrogen. Therefore, it appeared that the best way to carry out this experiment without the need for highly accurate quantitative analyses was to use deuterium as a tracer. The natural abundance of deuterium in H2 is only 0.015 pct. The tracer was obtained in the form of deuteroparaffin (CD,(CDJ, CD,) and 0.25 g were dissolved in 20 cc of mineral oil to form the lubricant to be used in the tests. The bearings used were New Departure Type QOLOO ball bearings with a ball diam of 0.187 in. Prior to adding the mineral oil-deuteroparaffin lubricant, the bearings were cleaned in warm trichloroethylene to remove the packing grease. After packing with the new deuterated lubricant, the bearings were operated in a bearing fatigue test machine under a radial load of 190 lb and a thrust load of 190 lb at a speed of 3800 rpm. The expected life under these conditions is about 500 hr. Two tests were made; one for a period of 27 hr and the other for a period of 102 hr. The bearings achieved a temperature of 120o F during the tests. When the tests were stopped the balls were mechanically removed from the bearings and were immediately placed in liquid nitrogen to reduce degassing until the analysis for deuterium could be made. Before analyzing, the balls were warmed to room temperature and scrubbed with several degreasing agents to remove all traces of the deuteroparaffin mixture. This cleaning procedure was shown to be satisfactory by running a control test in which one ball bearing was subjected to all parts of the test except running in the fatigue machine. The hydrogen and deuterium were removed from the balls using a hot extraction apparatus attached to a mass spectrometer. Four balls from each bearing were analyzed. Each one was analyzed separately by removing it from a cold storage volume of the hot extraction apparatus and transferring it to the oven tube with a magnet. As the gases were evolved they were analyzed with the mass spectrometer. Since the hydrogen and deuterium pass through steel in the atomic form and since there are many more hydrogen atoms than deuterium atoms in the sample, the probability of forming an HD molecule is greater than forming a D2 molecule. For this reason the evolution of HD and H was followed as each ball was placed in the oven. The results showed that as each ball from the test bearing was dropped into the oven, the mass spectrometer recording of the HD evolution increased by about ten divisions. When balls from the control test bearing were dropped into the oven, the increase was about one division or less. The hydrocarbon background in the mass spectrometer was also monitored to see if hydrocarbons or deuterocarbons were given off when the balls were dropped into the oven, but no change in the hydrocarbon peaks was observed. Since the balls contained a fair amount of residual hydrogen, isotope ratio measurements were made on the gas obtained from each ball. The D/H value found for those balls which had been operated in the fatigue testing machine was consistently about 0.3

Jan 1, 1962

By R. L. Bleifuss

Most pellets swell only slightly during reduction, but some swell so enormusly that their increase in size is termed catastrophic. Since catastrophic swelling produces irregularities in blast furnace operation, an understanding of the phenomenon is of practical as well as theoretical interest. Observations have shown that catastrophic swelling is characterized by the growth of a network of fine iron filaments. Evidence is presented to show that the growth of these filaments is promoted by the presence of calcium in the magnetite lattice of the original ore. During reduction, the limited mutual solubility of CaO and FeO produces an unstable condition that inhibits the uniform nucleation of metallic iron. Other elements in the magnetite lattice whose oxides are continuously soluble in FeO in the critical temperature range have no effect. Magmatic segregation or pyrometasomatic replacements are the most likely deposits to contain calciferous magnetite. Over the past few years there has been an increasing concern throughout the iron and steel industry over the tendency of pellets to swell during reduction. Although the tendency for swelling is only one of several attributes that determine the behavior of pellets in the blast furnace, swelling-reduction tests are now part of the normal evaluation procedure of many pellet consumers. During a swelling-reduction test, pellets display either the moderate increase in size known as normal swelling, or the enormous expansion known as catastrophic swelling. This paper is concerned with the origin and control of catastrophic swelling and how it is enhanced or inhibited by the presence of minor elements. Swelling Behavior The swelling behavior of pellets during reduction is indicated in Fig. 1. The lower curve represents normal swelling and the upper curve catastrophic swelling.' During the initial stages of reduction, that is, up to about 20-25% reduction, the two curves are considered to be equivalent. Beyond this point normal pellets undergo a gradual decrease in size with increased reduction. By contrast, pellets which exhibit catastrophic swelling show a second dramatic expansion between 25 and 70% reduction. The initial normal swelling develops as the hematite of the pellet is successively reduced to magnetite, and then to wustite. Work by Edstrom' and others has shown that the reduction of hematite to magnetite is accompanied by a 25% volume increase, whereas the magnetite to wustite stage shows a volume decrease. The volume increase overlaps the wustite field because magnetite is formed simultaneously with the wustite during topochemical reduction of the pellet. The catastrophic expansion is clearly related to the wustite, to

Jan 1, 1971

By C. W. Gibbs, E. K. Parks

In 1929 the Standard Oil Company of California commenced the development of a device for obtaining temperatures and pressures in flowing and shut-in wells and of suitable running equipment for such a recorder. Although simple in principle, the recorder has required much experimental work in its development. The various problems have now been solved to such an extent that it is believed that the apparatus affords a sturdy and reliable means for obtaining information regarding depth pressures,—apparatus that may be turned over to a well gang for routine operation. As an example of the rough usage the device will withstand a recent incident may be cited. Owing to failure of the lowering line at the conclusion of a run a recorder was dropped some 6300 ft. through 2 1/2-in. tubing filled with gassy oil. The device was fished out undamaged and with the pressure record intact, although the instrument had been subjected to a pressure greater than 2300 lb. per sq. in. for some 24 hr. after impact at bottom. Description of Recorder The instrument is of the continuous recording loaded spring type (Fig. I). Temperature is not recorded continuously but is obtained by maximum recording thermometers in an auxiliary thermometer well. The entire instrument assembly, from bottom of the recorder to top of the socket, is 6 1/2 ft. long and weighs less than 25 lb. The maximum outside diameter of the recorder shell is 1 1/4in., and all attachments need be no larger. This permits lowering the device inside 2-in. tubing. The operating principle is simple. The well pressure acts upon a piston A resisted by the extension of spring B. The spring deflection is recorded by a stylus C upon paper within the recording drum D. Springs.—To improve accuracy at lower maximum well pressures five interchangeable spring assemblies are used. These have maximum pressure ranges of from 250 to 5000 lb. per sq. in. Piston diameter is the same in all cases, and each spring is designed for a deflection of about 5 in. for maximum pressure loading. A complete spring assembly there-

Jan 1, 1934

Olof Venstrom (communication to the Secretary*):—In order to do justice to a property, once the largest producer of copper in the world, which is now being reopened, with a fair promise of again becoming important, I beg to add a few words in connection with Mr. Souder's remarks on the El Cobre copper-mines. The El Cobre copper-mines were worked by the old English

Jan 1, 1905

By J. W. Goss, M. J. Coolbaugh

Most grouting has been done to stop water flaw in mines and for stabilizing foundations of various man-made structures, a survey of the U.S. literature reveals. Apparently Sun Manuel is one of the first mines in this country to use grout extensively underground for strengthening and stabilizing ground in drifts, shafts, and stations. A comparison with other procedures as well as details of the Sun Manuel program are covered. The employment of pressure grouting as a ground stabilizer at the San Manuel Copper Corp. mine reduces delays in both development and production, lowers costs, and makes possible safer working conditions. It specifically reduces delays in haulage operations and permits the maintenance of normal ventilation. In development work this grouting allows faster excavation by cementing together highly fractured or broken ground that otherwise would require extensive cribbing or spiling. In drift repair, it consolidates the loose or fractured rock over the timber or steel drift supports, thus decreasing the frequency of repair, lessening the hazards from falling rock, and curtailing delays due to blockage of drifts by muckpiles and repair operations. Pressure grouting is the process of pumping an accurately controlled mixture of cement and water into loose, fractured, or porous rock. The ratio of water to cement varies according to the nature of the rock encountered, from the thinnest mixture of 30 gal of water per sack of cement, used to fill very fine fissures, to very thick grout of 5 gal of water per sack of cement, used to fill large fissures or extensive areas of loose, broken rock. The pumping pressures at San Manuel vary from about 100 to 1000 psi, depending upon the compactness of the rock, while at other mines the pressures sometimes go as high as 5000 psi. In order to grout an area in which ground water is encountered, the pumping pressure of the grout must be increased by an amount equal to the pressure of the ground water. GROUTING IN DEVELOPMENT WORK The areas under development at San Manuel include many sections of loose, highly fractured rock. Prior to the advent of the grouting program, drifts, shafts, and stations in these areas could not be excavated without utilizing extensive support such as cribbing, spiling, and breast boarding. This slowed down the development work and increased the costs considerably over that required for excavating in more competent ground. Now, when a particularly bad area is contacted, the mining is temporarily stopped while the bad portion of drift or shaft is grouted. After the grouting is completed, the excavating is resumed with an approximate decrease of 50 pct in lost time and costs. Grouting in Drifts and Turnouts: The grouting procedures and patterns used in drifts and turnouts are very similar. The standard procedure for grouting such a turnout is shown in Fig. 1. After the ground is supported as well as possible with cribbing or lagging, the gaps between the back lagging and side lagging are plugged with empty cement sacks or additional timber, if necessary. The ground surrounding the proposed turnout is then grouted in two stages. In the first stage, the broken and caved rock is drilled and grouted to a depth of 5 to 10 ft, depending on the depth of the broken rock. This stage forms a grouted seal that allows higher pressures to be used at depths beyond 10 ft without developing excessive leaks at the face. After a grout hole is drilled, a 10-ft long pipe is wedged tightly into it with empty cement sacks. Grout is then pumped into the hole until the pressure reaches 200 to 300 psi, and the pipe is subsequently removed if it hasn't become cemented in. No more than one hole at a time is drilled and grouted because the grout has a tendency to go from one hole into another, plugging up the latter. Five or six holes are usually adequate for the first 10 ft of grouting. Experience has shown bentonite to be a useful admixture to the grout, particularly when it is indicated that the grout is being lost into large fissures or voids. Bentonite increases the plasticity of the grout enabling it to remain in place more easily until it has begun to set. In the second stage, the longer holes are drilled through the previously grouted rock, after which the

Jan 1, 1961

By F. C. Farnham

THERE has been very little, if any, uniformity in the reference datum used for magnetometer surveys. It has been the practice to choose a base station at which the magnetic field is assumed to be normal and call the difference in field strength between a given station and this base the anomaly at the given station. For small-scale surveys latitude and longitude corrections may or may not be applied, but for large-scale surveys such corrections usually are applied. The United States Coast and Geodetic Survey maps showing lines of equal magnetic intensity are commonly used to determine the normal latitude and longitude variation by scaling values from the map for given points and computing the change per mile north and the change per mile east. This method has been quite satisfactory for isolated surveys, but when two surveys originating at different base stations were extended until they joined, difficulty arose, not only because of discrepancies between base-station values, but also because of differences between the latitude and longitude correction factors used for the separate surveys. It is the purpose of this paper to describe a reference datum for magnetometer surveys which, it is believed, will eliminate most of the difficulty arising from this source. In order to be satisfactory, a general datum for magnetometer sur-veys should be as close as possible to the observed field and still he based on some assumed distribution of magnet poles, in order that the "normal" value of any component of the field for any given point may be computed to as many significant figures as desired. Such a field has been com-puted, and a comparison of the intensity of its vertical component with the average vertical intensity for the United States as shown by the U.S.C.G.S. map of lines of equal intensity for 1935 is shown in Fig. 1.

Jan 1, 1939

By Walter B. M. Davidson

Phosphorus is one of the elements having the widest distribu tion, and phosphoric acid plays an important part in the composition of the crust of the earth. It is allied in various chemical combina- tions with many bases, of which lime, alumina and iron are the most common. It is difficult to state in what chemical combination phosphoric acid predominates in the crust of the earth, for while phosphate of lime, as the mineral which is sought for and found in deposits of economic value is the most familiar, it is probable that the phosphates of alumina and iron are the most usual forms in which phosphoric acid exists in all soils not essentially calcareous. It has been shown by thousands of analyses that all fertile soils contain from a trace to 0.5 per cent. of phosphoric acid. All limestones, dolomites and chalks contain it in proportions which, though usually small, are large enough to make careful analysis necessary in the selection of limestone as flux for iron-smelting. It is generally Trenton limestones that are found best for this purpose, the more recent strata being more phosphatic. In some places phosphoric acid replaces carbonic acid, and the limestone or chalk becomes phos phatic to a large degree, or sometimes pure phosphate of lime. The waters of the ocean, from very early periods, have contained phosphoric acid. Different analyses show varying contents; it is asserted that some portions of the Gulf Stream are more phos phatic than the surrounding waters of the Atlantic. Many springs, usually from limestone regions, contain soluble phosphates in vary ing quantities. I think it safe to assert that phosphorus is nearly the most widely and evenly distributed element on the surface of the earth, and probably the most subdivided. This can be readily understood when the important part which phosphoric acid plays and has played in the vital cosmos is taken into consideration. Phosphorus was on the earth in gaseous, liquid or solid form before the dawn of life, and since then all animal and vegetable creation have combined with the

Jan 1, 1893