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PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 RICHARD W HUNT 1883

Jan 1, 1917

By L. E. Young

The progress of mineral industry education will be limited to the period prior to World War II and will be considered as primarily a division of engineering education. Its relation to progress in the mineral industry and to the activities of the American Institute of Mining and Metallurgical Engineers will be emphasized. The history of mineral industry education has been recorded most completely and authoritatively by Dr. T. T. Read in his recent volume in the Seeley W. Mudd Series of American Institute of Mining and Metallurgical Engineers publications, entitled, The Development of Mineral Industry Education in the United States. Therefore, most of the historical details will be omitted from the discussion and an effort will be made to point out significant developments and to analyze trends. Introductory Statement and Significant Points in Progress Among the significant points in the development of mineral industry education in the United States since 1871, the following deserve particular mention: 1. The number of institutions offering undergraduate instruction has increased, particularly during the years 1890 to 1925; the number of students enrolled in undergraduate study has increased greatly, largely on account of the development of courses in petroleum engineering and increasing interest in metallurgy. 2. The selection of students to be admitted to undergraduate courses has been improved through the advisement, counseling, and guidance programs sponsored by the Engineers' Council for Professional Development. 3. Improved instruction methods all the training of the teaching staff have been promoted by the educational institutions themselves, but with the most effective stimulus and guidance of the American Society for Engineering Education and the Engineers' Council for Professional Development. 4. The accrediting of undergraduate curricula through the Engineers' Council for Professional Development, consitlering both qualitative and quantitative criteria, has done much to improve standards of instruction in engineering education for thc mineral industry. 5. Undergraduate curricula and courses are revised currently to meet the needs of the American mineral industry. New curricula are developed currently to permit specialization in technical fields, particularly in the fourth year of undergraduate work. 6. There has been a strengthening of the fundamental courses in mathematics, physics, mechanics, and chemistry, and at the same time these courses are being adapted to the most recent developments in the industry, including metallurgy, geophysics. petroleum engineering, petroleum technology, ceramics and SO forth. 7' There has been continuing improvement in plant and laboratory facilities of the educational institutions.

Jan 1, 1949

By T. Rosenqvist

From the chemical, metallurgical, and mineralogical points of view, the importance of thermodynamic data for metal-sulphides and sulphur dissolved in molten metal has long been realized. Such data will give a basis for thermo-dynamic calculations of processes such as roasting and the distribution of sulphur between molten metal and slags. Furthermore, it will help us understand the chemical forces which tie sulphur to the metal and to the melt. Thermodynamic studies of solid sulphides and the equilibria between solid sulphides and metals have been carried out in a rather large number of cases by several investigators. An excellent review of this work is given by Kelley.1 On the other hand, very little is known about the thermodynamic properties of molten sulphides and of sulphur dissolved in molten metal. The only system which previously has been investigated in this respect is the iron/sulphur system. The purpose of the present investigation was primarily to obtain further data for metalisulphur melts and the system silver/sulphur was chosen, not because this system was expected to be of special interest in itself, but because the silver/sulphur system is a typical example of a metal/sulphur system. Because of the low melting temperatures, the work could be carried out without appreciable furnace and refractory difficulties. The sulphur in this system possesses a rather high escaping tendency compared to most other metal/sulphur systems. By the method employed (reaction with hydrogen to form hydrogen sulphide) this gives ratios Ph2s/Ph2 up to 0.30, which may be determined accurately. 'rhermodynamic investigations of the heterogeneous reaction Ag2S +H2 —+ 2Ag + H2S have previously been carried out by Pelabon,2 Keyes and Felsing,3 Jellineb and Zakowski,4 Wat-anabe,6 and Britzke and Kapustinsky.6 Their results are in rather poor agreement. Experimental Part PRINCIPLE In the present invehgation the escaping tendency of sulphur from the condensed phase was determined by the reaction: S + H2 = H2S The ratio Ph2s/Ph2 is at constant temperature, directly proportional to the escaping tendency of sulphur and to its chemical activity in the condensed phase. (This ratio will subsequently be denoted by H2S/H2.) From this ratio and its variation with temperature and with change in the com- position of the condensed phase, thermodyrlamic quantities such as free energy and heat of reaction can be derived. The apparatus used is shown in Fig 1. The silver/sulphur alloy was placed in a crucible inside a refractory tube and mounted inside the furnace to the left. The tube was a part of a closed, gas-tight system in which the gas mixture could circulate until equilibrium was established. Circulation was maintained by the glass propeller to the right, driven by an external magnet, and promoted by the chimney action of the furnace. The gas passed up through the furnace, down into the crucible where it came in contact with the alloy, passed rapidly up through a narrow tube and out of the hot zone. After equilibrium was established between the gas and the condensed phase, the composition of the gas mixture was determined from its density. In its circulation, the gas mixture passed through a chamber (lower right on Fig 1) containing a buoyancy-balance, where the density of the gas was determined by magnetic balancing. From the measured density,

Jan 1, 1950

By G. Sachs, S. I. Liu

Introduction In a previous investigation on the effects of repeated strains of large magnitude on the aluminum alloy 24 ST, it was found that the reduction in ductility by straining in tension was partially restored by a subsequent compression.&apos; As illustrated by the dashed line in Fig I,$ the ductility (e~) retained after prestraining in tension by a certain amount (el) and measured in a subsequent tension test is represented by a straight line sloping down under 4s°. If a compression of the same magnitude as the first tension is inserted (€2 = — €1) between prestraining and final testing in tension, such a "balanced" tension-compression cycle yields a ductility considerably higher than that present after prestraining in tension only. The results of these tests can be correlated with those of an investigation on the effects of prestraining in compression.~ As also shown in Fig I, the ductility in subsequent tensile tests decreased with com- pression, at a rate considerably slower than that after prestraining in tension. The above discussed testing conditions can be considered as special cases of a general straining cycle, consisting of first, straining in tension by an amount el, subsequently straining in compression by an amount e2, and finally determining the retained &apos;ductility, e,, in a tensile test. Prestraining in tension is then represented by el > o and e2 = o. Prestraining in compression is given by e~ = o and e~ < o. Balanced cyclic straining is defined by the condition el > o and cz = — 61. In order to obtain further information on the effects of straining cycles consisting of tension and subsequent compression, further tests were made, varying both the tension strain, el, and the compression strain, e2, within extreme limits; el varied between 0.06 and 0.28 and e2 between — 0.008 and —0.h approximately. Apparently, such tests have not been previously performed. They revealed phenomena which have not been recognized to date, The results of the investigation are herewith reported, without attempting to correlate them with internal processes within the metal structure. However, in order to assist in an analysis of this type, the results have been represented in various manners. In addition, further test data on the effects of prestraining by compression were provided by using specimens of various contours (notched specimens) in the sub-

Jan 1, 1949

By Ralph E. Esarey, G. F. Fix

The oil and gas industry in Indiana in 1938 showed considerable improvement over the preceding year. Most of the drilling and development during the year, as in the past several years, was in the Indiana portion of the Illinois Basin, but increasing interest was apparent in the old Trenton area, for possibilities of further production in the Trenton formation and the underlying St. Peter sandstone. Interest in all other portions of the state was at a new peak, since many areas have never been prospected. Natural gas production continued to drop during 1938, since new discoveries have not been able to keep pace with the rapid decline in older areas. Oil production increased considerably, chiefly through the discovery of new fields. Older fields contributed about the same quantity of oil during 1938 as during the preceding year. There were 159 wells completed in Indiana during 1938, an increase of 25 over the preceding year. Of these, 48 were oil wells, 41 were gas, and &apos;70 failed to find commercial production. Forty-three, or about 20 per cent, were wildcat. Six of these were productive—three oil wells and three gas wells. Thirty-nine wells on which operations started during the year had riot been completed by Dec. 31. Fourteen others were temporarily abandoned, with the possibility that several will be drilled to completion in the near future. A new oil field (Heusler) was discovered in May 1938, in sees. 1 and 12, T. 7 S., R. 12 W., Posey County. Production was found in the Waltersburg (Upper (Chester) sandstone at a depth of approximately 1775 ft. At the close of the year, Heusler field had nine producing wells and two drilling. The Point township area, Posey County, near the confluence of the Wabash and Ohio Rivers, held promise of good production from the McClosky lime, but offsets to the, discovery well had only shows of oil. The discovery well declined rapidly in production arid was finally plugged. In the Oaktown field, Knox County, a wildcat came in with a good flow of gas, extending the field to the east, and proving considerably more acreage. A new gas area was discovered in Sullivan County, and four good wells were completed. The discovery well was in sec. 35, T. 8 N., R. 10 W., and had an initial

Jan 1, 1939

By Ralph E. Esarey, G. F. Fix

The oil and gas industry in Indiana in 1938 showed considerable improvement over the preceding year. Most of the drilling and development during the year, as in the past several years, was in the Indiana portion of the Illinois Basin, but increasing interest was apparent in the old Trenton area, for possibilities of further production in the Trenton formation and the underlying St. Peter sandstone. Interest in all other portions of the state was at a new peak, since many areas have never been prospected. Natural gas production continued to drop during 1938, since new discoveries have not been able to keep pace with the rapid decline in older areas. Oil production increased considerably, chiefly through the discovery of new fields. Older fields contributed about the same quantity of oil during 1938 as during the preceding year. There were 159 wells completed in Indiana during 1938, an increase of 25 over the preceding year. Of these, 48 were oil wells, 41 were gas, and &apos;70 failed to find commercial production. Forty-three, or about 20 per cent, were wildcat. Six of these were productive—three oil wells and three gas wells. Thirty-nine wells on which operations started during the year had riot been completed by Dec. 31. Fourteen others were temporarily abandoned, with the possibility that several will be drilled to completion in the near future. A new oil field (Heusler) was discovered in May 1938, in sees. 1 and 12, T. 7 S., R. 12 W., Posey County. Production was found in the Waltersburg (Upper (Chester) sandstone at a depth of approximately 1775 ft. At the close of the year, Heusler field had nine producing wells and two drilling. The Point township area, Posey County, near the confluence of the Wabash and Ohio Rivers, held promise of good production from the McClosky lime, but offsets to the, discovery well had only shows of oil. The discovery well declined rapidly in production arid was finally plugged. In the Oaktown field, Knox County, a wildcat came in with a good flow of gas, extending the field to the east, and proving considerably more acreage. A new gas area was discovered in Sullivan County, and four good wells were completed. The discovery well was in sec. 35, T. 8 N., R. 10 W., and had an initial

Jan 1, 1939

By B. D. Cullity, J. T. Norton, M. Telkes

M. Balicki—As one who some years ago spent much time searching for an alloy with high thermoelectric power that would be suitable for heat energy-electric energy converter based on the principle of a thermoelectric pile, I would like to make a few comments touching upon that aspect of this excellent paper. The specifications which one of the authors has formulated so aptly do not appear to me as complete, and I would like to add to them the following two demands: (1) Melting point not less than 500°C and (2) elongation on 2 in. at least 5 pct. Condition 1 would insure good thermodynamic efficiency of the pile by permitting a reasonably high temperature of the hot junction and at the same time making it suitable for such application as salvage of vast amounts of energy which is lost in the form of sensible heat of waste gas leaving industrial and other furnaces. Condition 2 is also a very important one; particularly, because of the fact that all elements and alloys which exhibit attractive thermoelectric properties seem to be as a rule very brittle. The design, erection, and maintenance of a pile incorporating a brittle material in one of the most crucial parts of the converter would be a very difficult and costly affair indeed. To illustrate this point I may mention great difficulties I encountered when trying to make thermocouples of silicon. Casting of 1/4-in. rods in iron or graphite mould yielded only broken pieces which had to be welded into a bar. Such a bar had to be handled very carefully during the determinations. Raising the molten silicon by vacuum into a silica tube and solidifying it there solved the problem of stability as well as that of electrical insulation of a bar. On tests this bar (98.5 pct Si) showed dE/dT = — 275.5 microvolts per degree C vs. copper. Thermocouples made of this grade of silicon and pure nickel developed 0.39 v when temperature of the hot junction was approximately 1000°C. The possibility Dr. Gonser has mentioned of trying to impart to metals good thermoelectric properties by alloying them with silicon, has been considered. The preliminary survey which I have made was, however, disappointing. Perhaps, it will be advisable to record the results obtained (table VI), as this might save repetition of search in fields already covered.

Jan 1, 1951

By R. S. French, W. R. Hibbard

M. Balicki—As one who some years ago spent much time searching for an alloy with high thermoelectric power that would be suitable for heat energy-electric energy converter based on the principle of a thermoelectric pile, I would like to make a few comments touching upon that aspect of this excellent paper. The specifications which one of the authors has formulated so aptly do not appear to me as complete, and I would like to add to them the following two demands: (1) Melting point not less than 500°C and (2) elongation on 2 in. at least 5 pct. Condition 1 would insure good thermodynamic efficiency of the pile by permitting a reasonably high temperature of the hot junction and at the same time making it suitable for such application as salvage of vast amounts of energy which is lost in the form of sensible heat of waste gas leaving industrial and other furnaces. Condition 2 is also a very important one; particularly, because of the fact that all elements and alloys which exhibit attractive thermoelectric properties seem to be as a rule very brittle. The design, erection, and maintenance of a pile incorporating a brittle material in one of the most crucial parts of the converter would be a very difficult and costly affair indeed. To illustrate this point I may mention great difficulties I encountered when trying to make thermocouples of silicon. Casting of 1/4-in. rods in iron or graphite mould yielded only broken pieces which had to be welded into a bar. Such a bar had to be handled very carefully during the determinations. Raising the molten silicon by vacuum into a silica tube and solidifying it there solved the problem of stability as well as that of electrical insulation of a bar. On tests this bar (98.5 pct Si) showed dE/dT = — 275.5 microvolts per degree C vs. copper. Thermocouples made of this grade of silicon and pure nickel developed 0.39 v when temperature of the hot junction was approximately 1000°C. The possibility Dr. Gonser has mentioned of trying to impart to metals good thermoelectric properties by alloying them with silicon, has been considered. The preliminary survey which I have made was, however, disappointing. Perhaps, it will be advisable to record the results obtained (table VI), as this might save repetition of search in fields already covered.

Jan 1, 1951

Andy H. Vassiliou – Introduction Ladies and gentlemen,.good evening and welcome to the Paul F. Kerr Memorial Symposium dinner. I believe we are all here to honor the memory of a great teacher and advisor, and a true friend -- Professor Kerr, or Dr. Kerr, or to most of us who were his students, "Pappy" Kerr. Most of us who attended the Paul F. Kerr Memorial Symposium earlier today at the New York Hilton had the opportunity to read, or listen to, or discuss scientific papers presented in honor of Dr. Kerr. In addition, all of the speakers had the opportunity to reminisce about their association with Dr. Kerr, who was credited as having contributed substantially to their graduate education and the development of their careers. Dr. Kerr&apos;s two daughters -- Ruth and Nancy -- who attended the Symposium at the Hilton are also here with us tonight. I think we should keep tonight&apos;s festivities on an informal basis since we are all old friends or former students of Dr. Kerr. Some of us may want to say a few words about our experiences at the time we were students at Columbia, and hopefully include some anecdotes relating to Professor Kerr. I would like to invite everyone to do so, but first we have arranged for two of us to be the lead speakers, whom I will introduce in a few moments.

Jan 1, 1985

Executive ARTHUR S DWIGHT, Chairman B THAYER CHARLES F RAND P MATHEWSON J V W REYNDERS Membership WILLIAM H BASSETT, Chairman W Y WESTERVELT Vice-chairman P MATHEWSON H G MOULTON F T RUBIDGE Finance WALTER H ALDRIDGE, Chairman GEORGE D BARRON GALEN H CLEVENGER

Jan 1, 1923

By Robert S. Schecter, Mark P. Walsh, Michael J. Humenick

In recent years in situ leach mining has emerged as a viable technology for the recovery of uranium from strata in South Texas which contain relatively low concentrations of uranium ore. Because the ore bodies lie within ground-water aquifers, a significant determinant in the economics is the requirement that such aquifers be protected from contamination. Since ammonia is one of the constituents of the leach solutions now being field tested, one environmental problem to be resolved is the removal of ammonia at the end of mining. A second related question is the fate of the ammonia which is not removed by the restoration procedure. This paper considers the displacement and migration of ammonium in a flowing electrolyte with concomitant ion exchange. The ion exchange is an important feature since, during the solution mining phase, ammonium saturates the mineral exchange sites and must be removed from these sites. A mathematical model is used to simulate this process and the model is tested against the results of laborator.y experiments. It is found that the simulations are adequate if an appropriate selection of parameters is made. The model is then used to investigate the effect of cation composition and concentration of the restoration medium as well as dispersion on the overall effectiveness of the process. It is concluded that increasing the concentration of monovalent ions in a solution containing a mixture of both monovalent and divalent ions decreases the adsorption selectivity of the divalent ions with respect to all monovalent ions including ammonium. Thus increasing the ionic concentration of a restoration fluid by increasing the concentration of a nonselectively adsorbed (with respect to ammonium) ion may have a very limited benefit.

Jan 1, 1979

By N. A. Zeigler

Considerable work has been and is being done on the changes of physical properties that take place in alloys at elevated temperatures, and much information on this subject is published. Much less is known, as pointed out by Rickett and Woodll about reactions between the alloys and atmospheric gases and still less is known abut changes within the alloy itself under the influence of heat and given atmosphere. Moreover, most of the work published has been done on the alloys of "heat-resisting" type, in which chromium is an essential ingredient, the behavior of all other alloys being quite unknown, except perhaps of decarburization produced at the surface by oxidizing atmospheres. It has been shown2 that iron, with total amount of foreign ingredients not exceeding 0.01 per cent, if heated in an oxidizing atmosphere at above 900" C., may be saturated with oxygen to 0.1 per cent. It was suspected that something of a similar nature may take place in iron-silicon alloys (transformer material), the mechanism of such processes being either a direct diffusion of oxygen into the alloy, or oxygen combining with silicon to form SiO2 or more complicated (silicate) inclusions. Another possibility to be considered was that during annealing in oxidizing atmospheres, when scale is being formed, silicon may oxidize preferentially at the surface, thus impoverishing the alloy in silicon. In collaboration with Dr. T. D. YensenP3 the writer set out to investigate this problem about two years ago in order to settle these questions. Testing Procedure In the first part of the investigation, two pieces of 4 per cent silicon iron, prepared in hydrogen atmospheres and forged to 3/4-in. square bar,

Jan 1, 1934

By B. Wilshire, W. J. Evans

W. J. Evans and 8. Wilshire SEVERAL recent investigations1-6 have shown that the strain, c, during transient and steady-state creep is well-represented by the expression: € = e0 + et(l - e-mt) + Esl [l] where Eo is the instantaneous strain on loading, ET the total transient strain, C, the steady creep rate! and m a constant relating to the rate of exhaustion of transient creep. However, it has been noted6 that deviations from this equation occur over the first 10 to 15 pct of the transient stage, when the creep rate, (. decreases more rapidly than is predicted by this equation. This rapid decrease has been attributed to a large change in work-hardening coefficient. It 1s widely accepted that steady-state creep results from a balance between the rate of strain hardcning h and the rate of recovery r (=-s(st) as: dE/dt = Es = r/h [2] Comparison of values obtained for h at the end of the initial extension and during steady creep suggests that h increases several fold during the transient stage. which has the effect of reducing the creep rate proportionally.7 To examine the dependence, on r and h, of the deformation behavior during transient and steady-state creep. a series of constant-stress creep tests was carried out at 413°C at 6000 psi using 70-30 a brass. Prelinlinary investigation showed that. with this material. the transient stage constituted a significant portion of the total creep life (-0.4tf. where tf is the time to fracture). The alloy. obtained from Metals Research Limited. was made from high-purity copper, 99.999 pct. and zinc. 99.99 pct. Heat treatment at 675°C for 4 1/2 gave a uniform grain size of 5 mm-1. Details of specimen preparation and creep testing procedures have been given previously.6 Values of h (?s/?E) were determined by measuring the instantaneous strain. ?E. which occurred on increasing the stress during creep by a small amount. ?s. Similarly. v (= -?s/ ?t) was derived from the incubation period. At, after a small decrease in stress.&apos; Several values of v and h were obtained throughout duplicate creep tests. using different stress increments in the range 300 to 800 psi. The accuracy with which Eq. [I] represents the present creep curves was established by determining the best value of the constants Es, Et, m , and 6, using a digital computer program based essentially on the graphical solution for this equation devised by Conway and Mullikan.9 About 40 strain/time readings were taken during transient and steady-state creep. Over most of the creep curve, the average difference between the measured reading and the calculated strain at the appropriate time was less than 0.0001. However.

Jan 1, 1969

By Ivor Hawkes

A wide variety of borehole gages have been developed for measuring rock stress. They all operate on the principle that stress changes around a borehole result in deformation that can be measured by the gage and interpreted in terms of the stress change either by calculation or calibration. In general terms, gages that comply with the borehole deformations are referred to as “deformation meters” and those that restrain the deformations by reason of their rigidity are referred to as “stress meters.” The main advantages claimed for stress meters are: their “stress” sensitivity is much less dependent on the rock modulus than that of deformation meters, and they are clamped firmly in the borehole. The use of each of the borehole gages developed for stress determinations in rock in the main has been confined to the laboratory responsible for its development. To be generally accepted a gage must meet the following specifications : 1) Gages to be left in place to measure stress changes must be relatively cheap, and if possible recoverable, so that large numbers can be used to obtain an overall picture of the changing conditions. This, of course, is not necessarily the case for recoverable gages designed for absolute rock stress measurements where usually only one or two gages are involved. 2) For use in the adverse environmental conditions encountered underground, it is essential that gages be robust, stable, and unaffected by high humidity, corrosive water, or dust. 3) Highly qualified technicians are rarely employed specifically for rock mechanics studies in mines or on civil engineering sites and there- fore gages designed for measuring stress changes must be easy to set and

Jan 1, 1972

By F. F. Poland

The purpose of this paper is to describe a new process for the refining of secondary copper-base metals and a specially designed high-temperature electric-resistor furnace used in the process for the distillation of zinc from these metals. The process was used for the conversion of nickel silver to cupronickel and to recover the zinc content in metallic form. It also proved applicable and economical for the treatment of scrap brass for separating and reclaiming the copper and zinc. The relatively large furnace developed for the distillation of zinc is described in detail, for it made economically possiblc the direct recovery of metallic zinc from scrap brass, which is a new step in the processing of such material. Considerable interest has been shown in the utilization of the distillation furnace for other metallurgical processes, where it is of advantage to operate in a controlled neutral or reducing atmosphere, or to avoid having the processed metal in contact with refractories other than carbon, or to operate at temperatures between 3000 and 4000°F. Purpose of Development It was recognized early in the war effort that nickel would become a critical metal. therefore all nickel stock and alloys containing relatively high percentages of nickel were frozen immediately. Among these alloys were considerable quantities of various grades of nickel silver, an alloy containing copper, nickel, zinc, and in some grades lead, also minor amounts of iron, manganese and other constituents. At the time there was no existing plant or process to eliminate the zinc, lead, and minor constituents so as to convert this metal to cupronickel, one of the important alloys needed by the U. S. Navy for condenser parts. Therefore the Bureau of Industrial Conservation of the War Production Board requested the executives of the leading nonferrous metal companies to have their metallurgical staffs study the problem of converting this metal to cupronickel conforming to U. S. Navy Specification 44T40. The composition specified therein is as follows: nickel, 29 to 32 per cent; zinc, 1.00; iron, 0.00 to 0.60; lead, 0.05; tin, 1.20; manganese, 0.00 to 1.00; total of other elemcnts (maximum). 0.50; copper, remainder. The problem in converting these alloys to cupronickel was the elimination of zinc, lead, iron, manganese, and other elements without appreciable loss of nickel to slags or other by-products. Revere Copper and Brass Incorporated, through its Research and Development Department, undertook to solve this problem. A Government-owned plant was built at Rome, N. Y., and there the conversion was made successfully.

Jan 1, 1949

By R. F. Sheldon

The discovery of the Carlin deposit was the result of discriminating geologic research and prospecting devoted to the objective of finding a gold deposit that could be mined by open pit methods. By the late 1950s, Newmont Mining Corp. was becoming increasingly concerned about the trend of rapidly rising underground mining costs unless bulk mining methods could be applied. The desirability of finding an open-pittable gold deposit was apparent. The attention of Newmont geologists was directed to Nevada by the publication of two papers: "Paleozoic rocks in North-central Nevada" (1958) and "Alinements of Mining Districts in North-central Nevada" (1960), both authored or co-authored by Ralph J. Roberts of the United States Geological Survey. John Livermore, geologist of Newmont Exploration Ltd., attended a talk given by Roberts in Ely, Nevada in the summer of 1961. These papers and the address by Roberts gave details concerning the Roberts Mountain overthrust, a 483 km (300-mile) long, shallowdipping fault which pushed clastic and volcanic rocks of early and middle Paleozoic age eastward over younger marine formations. Subsequent uplift and doming with consequent erosion had locally removed the upper plate strata exposing windows of lower plate carbonate rocks. Roberts noted that the principal mineral deposits of the region, including gold, were associated with these windows which exhibited a preferred alinement. In the summer and fall of 1961 Newmont&apos;s exploration geologists John Livermore and J. Alan Coope began a systematic examination of gold occurrences associated with these windows, aided by further discussion with geologists of the US Geological Survey. Attention was directed to the Lynn and Carlin windows, particularly to those formations lying immediately above and below the Roberts Mountain fault. It was appreciated at the time that many of the gold occurrences in the region were unusual in that no colours were obtained even when panning high grade samples. A large number of rock samples were collected and analysed using fire assaying procedures, and background values for gold were established. This systematic rock sampling resulted in the identification of a distinct area of anomalous gold values, and a block of claims was staked in late October, 1961. These claims, plus an adjoining optioned 32.4 ha (80 acres) of ground, cover the main area of the present Carlin gold mine. Prior to snowfall that winter, one of the bulldozed assessment pits required to establish a claim&apos;s discovery exposed 24 m (80 ft) of mineralization assaying 0.007 kg/t (0.22 oz per st) gold. In the spring of 1962 a program of trenching, sampling, and geological mapping followed by rotary drilling was underway. Other properties in the area were acquired. The generally undistinguished nature of the dolomitic siltstones and silty dolomitic limestones hosting the micron-sized gold particles, coupled with the lack of visually associated guide minerals, made identification of the gold bearing areas very difficult. The entire drill column had to be assayed to ensure that values were not overlooked, as very often sections that might be assumed to be waste turned out to be high grade. On September 10, 1962 a high grade intersection of 24 m (80 ft) assaying over 0.03 kg/t (1 oz per st) gold was encountered in the third hole drilled. An expanded program of both rotary and diamond drilling led to the further delineation of the ore body. By December 1963, the exploration program had established an initial reserve of 10 Mt (11 million st) grading 0.01 kg/t (0.32 oz per st) gold. A 1.8 kt/d (2,000 stpd) processing plant was constructed and the first gold bullion was poured in May, 1965, just two years and eight months after the discovery hole was drilled. REFERENCES Roberts, R.J., Holz, P.E., Gilluly, J., and Ferguson, H.G., 1958, "Paleozoic Rocks in North-central Nevada," Bulletin American Association of Petroleum Geologists, Vol. 42, No. 12. Roberts, R.J., 1960, "Alinements of Mining Districts in North-central Nevada," Professional Paper 400-B, US Geological Survey, Article 9.

Jan 1, 1985

By E. C. Houston

The presence in the Tennessee Valley of extensive deposits of olivine, a silicate of magnesium and iron that contains approximatcly 28 per cent magnesium, has been recognized since 1896 when Lewis8 published a survey of basic magnesium rocks of western North Carolina. A recent field survey by T.V.A.7 showed that more than two hundred million tons of high-grade olivine occurs above local drainage levels in western North Carolina and northern Georgia. Except for sporadic attempts to work the olivine for its nickel and chromium contents,10 the ore received little attention industrially until 1926 when Goldschmidt3 suggested its use in the manufacture of refractories. Only one instance is recorded of an attempt to utilize the ore commercially for its magnesium content;11 in this case a process was used in which olivine was treated with sulphuric acid, the resultant mixture was leached with water, and the leach solution was purified and evaporated to form epsom salts, which was the end product. As a part of its program of contributing to the development of the natural resources of the region, the Tennessee Valley Authority became interested in the olivine deposits as a source of metallic magnesium because of their high magnesium content and proximity to hydroelectric power. Studies were undertaken to determine the feasibility of producing magnesium chloride by extraction of olivine. The experimental work was carried out successively at the T.V.A. Minerals Testing Laboratory, Norris, Tenn., at the Georgia State Engineering Station,* Atlanta, Ga., and at the T.V.A. laboratory at Wilson Dam, Ala. The present paper describes a process, developed through the pilot-plant stage, whereby magnesium chloride suitable for reduction to metallic magnesium can be prepared from olivine by extraction with hydrochloric acid and subsequent purification. Research on the magnesium-from-olivine process, originally intended for peacetime use, was given impetus by the shortage of magnesium that existed at the beginning of the current world war. By the time the process was sufficiently developed to justify a proposal for its inclusion in the war program, the shortage had been met by expansion and development of other processes. However, it is believed that the magnesium-from-olivine process may have advantages that will warrant consideration of its use after the war, when the. economics of the various processes rather than production on a wartime scale will be the criterion for commercial production of magnesium. Description of Process Metallic magnesium is produced electro-lytically by the Dow and the Elektron

Jan 1, 1948

By E. C. Houston

The presence in the Tennessee Valley of extensive deposits of olivine, a silicate of magnesium and iron that contains approximatcly 28 per cent magnesium, has been recognized since 1896 when Lewis8 published a survey of basic magnesium rocks of western North Carolina. A recent field survey by T.V.A.7 showed that more than two hundred million tons of high-grade olivine occurs above local drainage levels in western North Carolina and northern Georgia. Except for sporadic attempts to work the olivine for its nickel and chromium contents,10 the ore received little attention industrially until 1926 when Goldschmidt3 suggested its use in the manufacture of refractories. Only one instance is recorded of an attempt to utilize the ore commercially for its magnesium content;11 in this case a process was used in which olivine was treated with sulphuric acid, the resultant mixture was leached with water, and the leach solution was purified and evaporated to form epsom salts, which was the end product. As a part of its program of contributing to the development of the natural resources of the region, the Tennessee Valley Authority became interested in the olivine deposits as a source of metallic magnesium because of their high magnesium content and proximity to hydroelectric power. Studies were undertaken to determine the feasibility of producing magnesium chloride by extraction of olivine. The experimental work was carried out successively at the T.V.A. Minerals Testing Laboratory, Norris, Tenn., at the Georgia State Engineering Station,* Atlanta, Ga., and at the T.V.A. laboratory at Wilson Dam, Ala. The present paper describes a process, developed through the pilot-plant stage, whereby magnesium chloride suitable for reduction to metallic magnesium can be prepared from olivine by extraction with hydrochloric acid and subsequent purification. Research on the magnesium-from-olivine process, originally intended for peacetime use, was given impetus by the shortage of magnesium that existed at the beginning of the current world war. By the time the process was sufficiently developed to justify a proposal for its inclusion in the war program, the shortage had been met by expansion and development of other processes. However, it is believed that the magnesium-from-olivine process may have advantages that will warrant consideration of its use after the war, when the. economics of the various processes rather than production on a wartime scale will be the criterion for commercial production of magnesium. Description of Process Metallic magnesium is produced electro-lytically by the Dow and the Elektron

Jan 1, 1948

By E. C. Houston

THE presence in the Tennessee Valley of extensive deposits of olivine, a silicate of magnesium and iron that contains approximately 28 per cent magnesium, has been recognized since 1896 when Lewis8 published a survey of basic magnesium rocks of western North Carolina. A recent field survey by T.V.A 7 showed that more than two hundred million tons of high-grade olivine occurs above local drainage levels in western North Carolina and northern Georgia. Except for sporadic attempts to work the olivine for its nickel and chromium contents,10 the ore received little attention industrially until 1926 when Goldschmidt3 suggested its use in the manufacture of refractories. Only one instance is recorded of an attempt to utilize the ore commercially for its magnesium content;" in this case a process was used in which olivine was treated with sulphuric acid, the resultant mixture was leached with water, and the leach solution was purified and evaporated to form epsom salts, which was the end product. As a part of its program of contributing to the development of the natural resources of the region, the Tennessee Valley Authority became interested in the olivine deposits as a source of metallic magnesium because of their high magnesium content and proximity to hydroelectric power. Studies were undertaken to determine the feasibility of producing magnesium chloride by extraction of olivine. The experimental work was carried out successively at the T.V.A. Minerals Testing Laboratory, Norris, Tenn., at the Georgia State Engineering Station,* Atlanta, Ga., and at the T.V.A. laboratory at Wilson Dam, Ala. The present paper describes a process, developed through the pilot-plant stage, whereby magnesium chloride suitable for reduction to metallic magnesium can be prepared from olivine by extraction with hydrochloric acid and subsequent purification. Research on the magnesium-from-olivine process, originally intended for peacetime use, was given impetus by the shortage of magnesium that existed at the beginning of the current world war. By the time the process was sufficiently developed to justify a proposal for its inclusion in the war program, the shortage had been met by expansion and development of other processes. However, it is believed that the magnesium-from-olivine process may have advantages that will warrant consideration of its use after the war, when the economics of the various processes rather than production on a wartime scale will be the criterion for commercial production of magnesium. DESCRIPTION OF PROCESS Metallic magnesium is produced electrolytically by the Dow and the Elektron

Jan 1, 1945

By E. C. Houston

The presence in the Tennessee Valley of extensive deposits of olivine, a silicate of magnesium and iron that contains approximately 28 per cent magnesium, has been recognized since 1896 when Lewis8 published a survey of basic magnesium rocks of western North Carolina. A recent field survey by T.V.A.7 showed that more than two hundred million tons of high-grade olivine occurs above local drainage levels in western North Carolina and northern Georgia. Except for sporadic attempts to work the olivine for its nickel and chromium contents,10 the ore received little attention industrially until 1926 when Goldschmidt3 suggested its use in the manufacture of refractories. Only one instance is recorded of an attempt to utilize the ore commercially for its magnesium content;" in this case a process was used in which olivine was treated with sulphuric acid, the resultant mixture was leached with water, and the leach solution was purified and evaporated to form epsom salts, which was the end product. As a part of its program of contributing to the development of the natural resources of the region, the Tennessee Valley Authority became interested in the olivine deposits as a source of metallic magnesium because of their high magnesium content and proximity to hydroelectric power. Studies were undertaken to determine the feasibility of producing magnesium chloride by extraction of olivine. The experimental work was carried out successively at the T.V.A. Minerals Testing Laboratory, Norris, Tenn., at the Georgia State Engineering Station,* Atlanta, Ga., and at the T.V.A. laboratory at Wilson Dam, Ala. The present paper describes a process. developed through the pilot-plant stage, whereby magnesium chloride suitable for reduction to metallic magnesium can be prepared from olivine by extraction with hydrochloric acid and subsequent purification. Research on the magnesium-from-olivine process, originally intended for peacetime use, was given impetus by the shortage of magnesium that existed at the beginning of the current world war. By the time the process was sufficiently developed to justify a proposal for its inclusion in the war program, the shortage had been met by expansion and development of other processes. However, it is believed that the magnesium-from-olivine process may have advantages that will warrant consideration of its use after the war, when the economics of the various processes rather than production on a wartime scale will be the criterion for commercial production of magnesium. Description OF Process Metallic magnesium is produced electro-lytically by the Dow and the Elektron

Jan 1, 1949