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By David A. Keys

The object of this investigation was to determine with a vertical magnetic variometer the extent of the titaniferous ore deposit that occurs not far from Ivry in Terrebonne County, Quebec, about 70 miles north of Montreal. The Ivry mine, on lots 37 and 38 of range V, Beres-ford township, Quebec, is one of the largest and most accessible to transportation of the deposits of ilmenite in Quebec. The ore consists of an aggregate of ilmenite anhedra serving as host for numerous fine plaques of hematite. No magnetite is known from any occurrence near this lot, and in this way the deposit differs from many others that contain a large percentage of magnetite with the ilmenite. The deposit at Ivry thus has much lower magnetic susceptibility than those containing abundant magnetite, and a sensitive magnetometer was necessary for the work, although a body of magnetite with ilmenite about a mile from the Ivry mine was successfully prospected with a dip needle. The principal orebody is exposed in a quarry known as the Ivry mine, from which about 16,000 tons of ore have been shipped. Small exposures of ilmenite isolated by drift serve to show the presence at the surface of some of the bodies indicated by the magnetometer, but most of the hill is covered with glacial till and second growth hardwood. At the lower levels the till gives place to fluvioglacial sands and gravels from which the forest has been cleared. The increasing thickness of the sand and gravel as the hill descends makes the tracing outward of the deposits from the rocky knob of anorthosite a difficult matter. Within the orebodies too, some masses of anorthosite persist, which may account for some local irregularities. Fig. 1 is a photomicrograph, taken by reflected light, of a typical specimen of the ore. The dark patches are hematite and the light parts are ilmenite No trace of magnetite was found. Pig. 2 is a photomicrograph of a thin section of the country rock showing the texture of the anorthosite. The mean of four analyses quoted by Robinson1 is: titaninm, 19.26 per cent; iron 45.41 per cent. The ilmenite ore is not sufficiently magnetic to deflect an ordinary compass needle, but the effects of the induced magnetism in the ore by

Jan 1, 1940

By David A. Keys

The object of this investigation was to determine with a vertical magnetic variometer the extent of the titaniferous ore deposit that occurs not far from Ivry in Terrebonne County, Quebec, about 70 miles north of Montreal. The Ivry mine, on lots 37 and 38 of range V, Beres-ford township, Quebec, is one of the largest and most accessible to transportation of the deposits of ilmenite in Quebec. The ore consists of an aggregate of ilmenite anhedra serving as host for numerous fine plaques of hematite. No magnetite is known from any occurrence near this lot, and in this way the deposit differs from many others that contain a large percentage of magnetite with the ilmenite. The deposit at Ivry thus has much lower magnetic susceptibility than those containing abundant magnetite, and a sensitive magnetometer was necessary for the work, although a body of magnetite with ilmenite about a mile from the Ivry mine was successfully prospected with a dip needle. The principal orebody is exposed in a quarry known as the Ivry mine, from which about 16,000 tons of ore have been shipped. Small exposures of ilmenite isolated by drift serve to show the presence at the surface of some of the bodies indicated by the magnetometer, but most of the hill is covered with glacial till and second growth hardwood. At the lower levels the till gives place to fluvioglacial sands and gravels from which the forest has been cleared. The increasing thickness of the sand and gravel as the hill descends makes the tracing outward of the deposits from the rocky knob of anorthosite a difficult matter. Within the orebodies too, some masses of anorthosite persist, which may account for some local irregularities. Fig. 1 is a photomicrograph, taken by reflected light, of a typical specimen of the ore. The dark patches are hematite and the light parts are ilmenite No trace of magnetite was found. Pig. 2 is a photomicrograph of a thin section of the country rock showing the texture of the anorthosite. The mean of four analyses quoted by Robinson1 is: titaninm, 19.26 per cent; iron 45.41 per cent. The ilmenite ore is not sufficiently magnetic to deflect an ordinary compass needle, but the effects of the induced magnetism in the ore by

Jan 1, 1940

By Otto C. Kopp, Thomas B. Crattie, Dennis R. Owen

Whole-rock analyses of limestones, fine-gralned dolostones and coarser-grained dolostones adjacent to mineralized breccias (Coy mine, Mascot-Jefferson City district) were compared with similar lithologies adjacent to apparently non-mineralized breccias at the new Thorn Hill section located approximately 39 km north of the Coy mine. Specimens were analyzed for Ca, Mg, Si, Al, K, Fe, Mn, Sr, Br, C1, S, Ti and P using X-ray fluorescence analysis. The concentrations of the major and most minor elements for Thorn Hill specimens fall within the range of concentrations for Coy mine specimens; however, significant differences (probability < 0.05) were noted for Fe, C1 and Br for fine-grained dolostones and for MgO, Fe and Mn for the coarser-grained dolostones. No significant differences were detected for the limestones.

Jan 1, 1985

By J. C. HEILMAN

THE Tri-State district, named from its situation in three States, lies in the northeast corner of Oklahoma, the southeast corner of Kansas and the adjacent part of Missouri east of the common corner of the above States. Production in the past eighty years has come from scattered mines within an area of some 35 miles east and west, by 25 miles north and south, although the actual area of the mined ground is but a small fraction of this territory. The land is leased from the individual land-owners, and the size of the tracts varies from 4.0 to 200 acres, the smaller sized tracts predominating. The leases usually call for a royalty of 7% to 15 per cent of the gross receipts of the concentrates, continuous operation during the life of the lease and specifically set out that no ores can be brought in from a foreign lease for custom milling nor can any ore be removed from the lease for milling. The ownership of the tailings remains with the land-owner.

Jan 1, 1931

Some years ago the open Hearth Committee of the Institute reached the conclusion that the reading of "set" papers tended to preclude the specific and detailed discussion of specialized problems of current interest to those operating steel plants. As an innovation the Committee distributed in advance of the meeting in May, 1927, a questionnaire containing a list of 27 topics involving operating problems. The subsequent discussion of the questions, participated in by 37 members, was a conspicuous success. Semiannual meetings have been held since; and at the conference of November, 1929, at Chicago, 131 men were present and the minutes comprised a book of 133 printed pages, thereby, indicating the growing value of the conference in the eyes of both the metallurgists themselves and the companies that employed them. With this example in mind, the Directors felt that definite advantages would accrue to a similar conference to be participated in by smelter officials and metallurgists engaged in the operation of copper reverberatory furnaces. The settlement of the Carson litigation, which for several years had virtually stopped public discussion of reverberatory practice, offered an opportune time for launching the scheme. Although the Conference may become largely self-financing in the future, some funds were regarded as necessary to conduct the first meeting. The members of the Rocky Mountain Income Committee, in view of the fact that copper smelting was essentially an activity of the Rocky Mountain area, recommended the project be, in effect, underwritten by the Fund, and the directors approved an appropriation for this purpose. Invitations were extended to high executives of the various-companies interested to send representatives to an initial meeting to be held at Salt Lake City, May 26-27. The response was enthusiastic. Twenty-three metallurgists representing 12 different plants were present to discuss the comprehensive-program relating to construction and operating phases of reverberatory smelting. It was understood that the record was not to be included in the regular publications of the Institute but that it would be prepared for private distribution among the participants and the officials of their companies. That the exchange of views and experience was no less instructive and stimulating than it was frank, full and informal is indicated by the following transcript of the minutes of the meeting.

Jan 1, 1930

By Samuel Taylor

IT is customary for the president of an engineering society, in his annual address, to describe either some engineering problem with which he has beer connected or to review the work of the society during his administration. My first thought, this being the sesquicentennial year of our nation, was to review the advance in coal mining for the past fifty years, during which period I have been more or less intimately con-nected with the bituminous coal industry, and have personally witnessed most of the great changes which have occurred in methods and machinery used in the production of coal, but preparation of the requisite address would take more time than could be spared to prepare it, and its presentation would consume so much time that it .would not be suitable. The new arrangement providing for giving the presi-dent&apos;s address at the business meeting makes it more .appropriate to review the work of the Institute during the past year, together with some suggestions which appeal to me as being of advantage to the future wel-fare of the Institute, which I will try to do briefly. The work of the business office has been reviewed in the Secretary&apos;s report and it will not be necessary for me to dwell on it. Suffice it to say, it seems to be going along very well. Additional work could be done which would be to the advantage of the Institute, if we had the money with which to defray the necessary ex-pense incident to it, but I will refer to this again later. I would be derelict if I did not refer to the splendid work of the Secretary and the Assistant Secretary. Keeping in touch with all the sections, which number now about 26, and affiliated student societies which number 40, besides special committees, and represent-ing the Institute on various boards, provides work enough to occupy the Secretary&apos;s time almost exclu-sively. In addition to this the Secretary and the As-sistant Secretary have the work of editing and publishing the TRANSACTIONS of the Institute; the issuing of the magazine, MINING AND METALLURGY, in the splendid manner in which it goes out to the mem-bership is no light task and I think they should receive the commendation of the membership for this work.

Jan 3, 1927

By Krahmann, Rudolf

THE following is an account of a survey undertaken to test the possibility of outlining a kimberlite pipe by magnetouietric methods. Kimberlite is a basic igneous rock closely related to melilite-basalt or alnoite, which occurs either in the form of volcanic plugs or as dikes intruded into rocks of various types and geological ages up to and includ¬ing the Lower Cretaceous. The famous diamond mines of South Africa are all in kimberlite pipes and these pipes are probably the original source as well of the vast alluvial deposits found in various parts of the country. The pipe chosen for this experiment is one that &apos; occurs on the farm Goedgevonden No. 20, about sixteen miles north of the village of Klerksdorp and ninety miles southwest of Johannesburg. Some prospecting has been done on this pipe and diamonds were produced from it but not in paying quantities. The magnetometric survey was made in June, 1932, by R. Krahmann and H. Wallisch and the results are shown on the accompanying plan. On the plan are shown also the boundaries of the pipe as exposed at the surface and details in regard to the surrounding foundations. These are taken from a geological survey made at a later date by W. Beetz, of Johannesburg.

Jan 1, 1935

By L. Sturkey

Quantitative X-ray diffraction studies of the precipitation of thorium in a Mg + 3.3 Th + 0.51 Zr alloy (HK31A) in both the as-cast and cold-worked states show that the precipitation may be described by f = 1 - e(t/T)1/2 over most of the aging period. The effects of cold work and temperature changes are determined. The precipitation of tile equilibrium Mg-Th compotund is Preceded by the formation of a transition phase of higher thorium content, with the cowposition Mg2Th and with a Laves-phase structure. Thorium-containing alloys of magnesium have assumed considerable commercial importance, especially for applications requiring exposures to temperatures greater than 500°F for appreciable lengths of time. The principal commercial wrought alloys in this system are HK31A, containing nominally 3 pet by weight thorium and about 0.7 pet by weight zirconium: and HM21A. containing 2 pet by weight thorium and 1 pet by weight manganese. These two alloys retain a high level of properties even after exposures of 100 hr at 600°F, while the more common alloys containing aluminum and zinc are badly overaged by these conditions. Therefore, in order to obtain some insight into the mechanism by which thorium produces high temperature stability in these wrought alloys, it seems desirable to investi- gate the effect of temperature and mechanical working on the precipitation processes involving thorium. Since the scattering power of a thorium atom for CuKa X-ray radiation is about ten times that for a magnesium atom, the magnesium alloys containing about 3 pet by weight thorium are ideal for quantitative measurements by X-ray diffraction of the amount of Mg-Th compound present at any time. Such quantitative measurements should be of theoretical importance in the study of the effects of time, temperature, and deformation on precipitation and precipitation hardening. Of the two commercial alloys, HM21A and HK31A, the latter is certainly the most suitable for study: In the Mg-Th-Zr2 system, only Mg-Th compounds need be considered, since no ternary compounds or binary Th-Zr3 and Mg-Zr4 compounds exist. The Zr is added to this alloy as a grain refining agent and probably plays a secondary role in precipitation. On the other hand. thorium and manganese form many

Jan 1, 1961

By R. E. Pray, M. C. Fuerstenau, J. D. Miller, B. F. Perinne

Quartz cannot be floated with potassium amyl xanthate as collector at any pH. Complete flotation is achieved with certain minimal additions of amyl xanthate and Pb from pH 5.8 to 8.5 and with amyl xanthate and Zn from pH 7.5 to 8.1. The active species of these metal ions responsible for activation are shown to be PbOH and ZnOH No flotation was effected when Cu and Mg were added as activators. Previous work1,2,3,4,5,6,7 has shown that quartz may be floated in the presence of sulfonate or soap when the following two criteria are met: 1) some portion of the added metal ion has hydro-lyzed to its first hydroxy complex, and 2) a precipitate of the metal-collector has formed. Since sulfonate and soap, two substantially different anionic collectors, conform to these criteria, this phenomenon may well be expected to be of a general nature. In this view then, it would appear that any anionic collector, including xanthates, should also float quartz when these two criteria are met. The object of this paper is to demonstrate the conditions under which quartz will respond to flotation in the presence of potassium amyl xanthate. EXPERIMENTAL MATERIALS AND TECHNIQUES Quartz was prepared by leaching the sized sample (48 x 150 mesh) with HC1 until no iron could be detected in the leach liquor. Conductivity water, made by passing distilled water through an ion exchange column, was used in the investigation. Potassium amyl xanthate was selected as collector. Purification of this reagent was effected with the following method: 1) a laboratory sample of potassium amyl xanthate was dissolved to saturation in hot ethyl alcohol and filtered several times while still hot, 2) the filtrate was cooled, during which time potassium amyl xanthate crystallized out of solution; the xanthate was then separated from the solution by filtration, 3) the amyl xanthate was dissolved in fresh hot ethyl alcohol and filtered, 4) step (2) was repeated, 5) the crystalline potassium amyl xanthate was washed with ethyl ether five times, and 6) the xanthate was dried for 24 hours under continuous vacuum. Inorganic impurities are insoluble in hot ethyl alcohol whereas dixanthogen is soluble in ethyl ether. Five-gram charges of 48x150 mesh quartz were conditioned for 3 min in 125 cc of solution containing the reagents and were floated with the small-scale cell and procedure described in previous papers.478 Reagent grade HCl and NaOH were used for pH adjustment, while reagent n-amyl alcohol was added as frother. Frother addition is necessary with this technique, but it should be mentioned that data, similar to those shown in Fig. 2 for 1 x10-4 mole per liter Pb++ and 1 X 10-4 mole per liter AX-, were also obtained with a Hallimond cell in the absence of frother. EXPERIMENTAL RESULTS Clean quartz could not be floated with amyl xanthate at any pH. Flotation was achieved under certain conditions, however, when various metal ions were added to the system. The activating ions used were lead, zinc, copper and magnesium, added as reagent grade chloride salts. Lead as Activator: The effect of Pb++ as activator was examined at five different additions of amyl xanthate (Fig. 1, 2 and 3). When 1x 10-5 mole per liter xanthate was added in the presence of 1 x 10"4 mole per liter Pb ++, no flotation was obtained at pH 6.5 or below, while a recovery of about 60% was effected at pH 7. When the pH was increased to 7.8, no flotation was again obtained, Complete depression was noted from pH 7.8 to about 10, at which point a recovery of about 30% was achieved. At about pH 11, the precipitate of lead amyl xanthate which was present below this pH dissolved and complete depression occurred. When 2.5x 10-5 mole per liter xanthate was added with the same lead addition, no flotation was obtained at pH 5.8 and below, whereas a recovery of

Jan 1, 1965

By A. M. Kivari

OPERATIONS at the cement plant of the Permanente Corporation, in the hills about 45 miles south of San Francisco and 12 miles west of San Jose, are interesting to the members because of the adoption of modern hydrometallurgical methods for handling and beneficiating raw materials. Closed-circuit grinding, classification, hydro-separation, flotation, agitation, and thickening are familiar terms at this cement plant. These methods make it possible to process refractory limestone into suitable materials for the manufacture of modern cements. Construction of the plant, having originally a design capacity of 7000 bbl. of cement per day, was started in June 1939, and the first clinker was ground on the following Christmas Day. At present the capacity is about 12,000 bbl. of finished cement per 24 hr., most of the production being low-heat cement.† About 3130 tons of limestone, 620 tons 0f clay and 100 tons of gypsum are required daily for this output. Occasionally iron oxide is added to the clay to obtain the desired composition. This, together with the gypsum, is purchased from outside sources. Up to the present time, the corporation has produced low-heat, normal, moderate heat, moderate-sulphate-resisting, high-early-strength, oil-well, modified-oil-well, and plastic cements. Most of the present production is for Shasta Dam, near Redding, Calif., the total demand being 5,800,000 bbl, of cement. Following are some of the cement requirements of the Shasta Dam specifications: [PERCENT Chemical composition: Loss in ignition2.25 Insoluble residue0.75 SO32.25 MgO5.00 Uncombined lime in clinker (CaO)1 .25 Percentage of iron oxide to alumina ratio1.5 Compound composition: Tricalcium silicate (3CaO.Si02)Not more than 3,5 Dicalcium silicate (2CaO.Si02)Not less than 40 and not more than 65 Tricalcium aluminate (3CaO.Al2O7)Not more than 7 Tetracalcium aluminoferrite (4CaO.A12O3.Fe203) Not more than 0 Fineness:] The average specific surface in the bin sampled shall be not less than 1800 sq. cm. per gram and no individual sample less than 1600 sq. centimeters. Compressive strength: The average compressive strength-in pounds per square inch of three mortar cubes composed of one part cement and 2.75 parts fine testing sand, by weight, shall be equal to or greater than the following:

Jan 1, 1941

By Luke L. Y. Chang, Bert Phillips

ThE tendency toward further oxidation of the intermediate oxides and the high volatilization rates of the higher oxides have prevented direct attainment of equilibrium data for the system tungsten-oxygen. As a result, St. Pierre et al.1 have proposed a phase diagram (to 800°C) based on thermody-namic data to 1200°C for the known tungsten oxides (WO2z, W18O49, W20O58, and WO3) and a report on a tungsten suboxide W3O.2 Recent modification of a technique previously described3 5 now permits adequate preservation of compositions of mixtures of metallic tungsten and metal oxides (e.g., of tungsten, cobalt, calcium, samarium, titanium) in order that condensed phase relations may be established to 1700 This method has been applied to study the high-temperature stability of tungsten oxides. In the method used, the desired compositions were sealed in nonreactive containers such that only a small gas volume remained. Each sample then established its own equilibrium atmosphere at temperature. This method has advantages in the study of systems of the W-0 type where knowledge of the condensed phases is desirable but for which composition and pressure of the gas phase are not readily attainable because of oxide volatility. Mixtures of 99.99 pct tungsten metal powder and purified tungsten anhydride (WO3) or in some cases W18O49* were equilibrated in pellet form in sealed

Jan 1, 1964

By Yves Dardel

The literature concerning the remelting of alunlinum and its alloys is very rich. Unfortunately the majority of the papers on this subject have no scientific value, for the theories or explanations are too often in opposition to the laws of physical chemistry. Furthermore only a few of the methods of purification are considered in the literature. Hence it has seemed necessary to the author to sketch a general theory of the purification of secondary aluminum. The purpose of the purification is to eliminate the impurities that the charges, and the atmosphere of the furnaces bring into the bath during the successive remelt-ings. Indeed scrap as well as metal can be used when soiled with oil, greases, water, or others, if it has been sufficiently dried and contains oxides. At the melting point of the metal, the oils and greases are decomposed into their constituent elements H², O2, H²O, co², CO, CH,, and others. These gases are added to the corresponding gases in the atmosphere of the furnace. The impurities introduced into the metal during the remelting will accordingly be the products resulting from the action of these gases on the liquid bath. The quantity of hydrogen that is soluble in aluminum and its alloys is given by the relation of sieverts3 as a function of its partial pressure PH2 in the atmosphere m = K vPH² [I] where K is a constant, which depends only upon the temperature and increases with it. The experiments of Rijntgen and Braun4, RÖntgen and M611er5, Bircum-shaw6 and Winterhagerl have rendered it possible to determine the value of K, when the temperature is less than 1.000°C. One obtains: log K = - 4,702.5T + o 238 [2] Besides its usual significance, the term Ph~ represents also the internal pressure of dissolved hydrogen, since in the equilibrium, that is1 when no gas exchange Occurs between the two phases, the Pressures of hydrogen in the metal and in the atmosphere must be equal. Eq I shows that when the partial pressure of H2 increases the amount of dissolved hydrogen in equilibrium increases, and that, if the contrary Occurs, the quantity of H² should diminish. However, if for any reason the diffusion of hydrogen is hindered and the total amount of dissolved gas remains constant while the temperature decreases, the internal pressure of H² increases until it reaches the value of the hydrostatic pressure. At this point, bubbles of hydrogen appear in the bath and escape out of it. The amount of hydrogen in the metal is then limited by a a depending On the hydro- static pressure, which is practically equal to one atmosphere. Indeed hydrogen does not accumulate in the form of a hydride appearing as a separate solid phase. However1 even the mechanism of the solubility is not yet elucidated. One does not know exactly as yet, whether the

Jan 1, 1949

By B. N. Das, H. E. LaBelle, G. A. Wolf

ZnxHg1-xTe and GUPxAS1-x crystals have been grown from solution by a traveling heater method (THM). In a floating zone type fashion a solution zone sandwich of liquidus composition is made to migrate through feed material of solidus composition by a slow-speed movement of <0.25 mm per hr of the total charge through a stationary radiation or rf heater. ZnxHg1-xTe of composition 0 < x < 0.3 and GUPxAS1-x of composition 0.5 < x < 0.7 have thus been grown from their solution in liquid tellurium and gallium, respectively. A simplified analysis of heat and material transport is given. In this method, Proper adjustment of the temperature distribution along the liquid solution zone axis eliminates instability of the crystal growth front and constitutional supercooling. 1) ZnxHg1—xTe: The solid-solution telluride was grown in sealed quartz tubes at a temperature of 500 to 650°C. For first Preparations mechanical mixtures SINGLE crystals of solid solutions of III-V and II-VI compounds have been grown by various techniques from the melt, from the gaseous phase, or from solutions in of ZnTe and HgTe were used. X-ray determinations showed the resulting crystals to be homogeneous throughout their entire length, except for the end sections. The homogeneity is greatly improved by reusing the ingots obtained from first Preparations as feed material in subsequent crystal growth runs. Ingots of up to 4.5 cm have thus been obtained. 2) GaPxAs1-x: Crystals were grown in a EN crucible at a temperature of 1050°C. For first Preparation a mechanical mixture of Gap and GaAs was cemented together by a minimum amount of liquid gallium through "wet" grinding of Gap and GaAs crystals in the liquid metal and subsequent exuding of excess gallium by compacting of the charge in the EN crucible. Electron microprobe measurements using P-Ka and As-Ka radiation showed uniformity over a length of 0.4 cm. Properties of the various Preparations are described. liquid metals.&apos;-&apos; Their growth from the melt by passing a liquid zone of pseudobinary liquidus composition through a solid rod of solidus composition is generally a convenient method of growth of single crystals of solid solutions of homogeneous composition. This method loses much of its usefulness, however, if the melting point or the vapor pressure of the solid solution is high. In the case of a compound having a high melting

Jan 1, 1969

By E. A. Holbrook

MINING Metallurgy, and Petroleum Engineering department in our colleges are facing a crisis; indeed, conditions that threaten their very existence. Unless the Army, Navy, and War Manpower Commission change their present policy, within two years mineral industries education as now carried on will die, because no ablebodied students will be left in the course. If this is the decision of our responsible governmental agencies we of the mining schools must perhaps accept it as a war measure. It might be well however, for the executive of our mining metallurgical, and oil companies to look ahead a, to where they are to recruit a supply of young technically trained engineers. You can no more operate a mine, a steel plant or an oil company without trained engineers than you can operate a battleship without mechanical and electrical engineers.

Jan 1, 1943

By M. von Heimendahl, G. Thomas

The microstructure of TD-Ni has been examined by transmission electron microscopy in the extruded, annealed. and deformed states. The tensile properties hove been correlated with the observed microstructures and the results ore com-pared with those obtained from pure nickel. The important conclusions are that the thorin particles in TD-Ni act as strong burriers to dislocntion motion during both deformation (slip) and annealing (climb). During deformation. the dislocations tangle around the particles and a cell structure is devleloped after 10 pct or more strain. The cell size appears to be determined by the spacing of the largest particles and is about five times smaller than that in pure nickel for the same strain. The higher work-hardening rate in TD-Ni compared to nickel is probably due to the more rapid rate of dislocation multiplication in the alloy as a result of dislocation-particle interactions. The Th0,particles inhibit recrystallization and twin growh so that some strengthening may arise from the high density of small annealing twins. THE strengthening of materials due to the presence of a dispersed second phase has been the subject of considerable experimental and theoretical investigation in recent years. One of the newest dispersion-strengthened alloys to be developed is TD-Ni,1 a system of approximately 2 vol pct thoria (ThO2) dispersed in a matrix of commercially pure nickel. This material is fabricated by powder-metallurgical techniques and offers high-temperature stability and useful mechanical properties virtually to the melting point of the base metal. While the mechanical properties of this system have been investigated,2,3 there have been no reports in the literature concerning the microstruc-ture of TD-Ni and its correlation to mechanical properties. This paper describes a transmission electron microscopy investigation of the micro-structure of TD-Ni together with its mechanical properties. The results are compared with the structure and properties of pure nickel.

Jan 1, 1964

By Donald H. McLaughlin

THE activity and enthusiasm of pioneers still prevail among workers in applied geophysics1.- Within the year, new devices have .been tried out, instruments and technique have been improved and the methods of application to commercial problems have been increased in many ingenious ways. There is still great need for more skillful interpretation of results in terms of geology, but oil the whole geophysical prospecting is making encouraging progress toward finding its proper place and function in engineering and geological practice. Spectacular successes continue to be reported, particularly .from the Gulf Coast, where the race for salt domes has not slackened, and encouraging results have been giined elsewhere in the mapping of structures in the search for oil. In the mining field, however, it can hardly be claimed that the same measure of success has been obtained, for brilliant efforts worthy of wide recognition have been overshadowed to some eatent by the unfortunate outcome of surveys undertaken unwisely without recognition of the limitations of the work. Consequently, hopes were aroused that could not be fulfilled, and it must be admitted in an impartial survey that there are a few regions, chiefly in the far north, where the standing of geophysical prospecting is somewhat doubtful and where the course of public opinion regarding it shows a certain similarity to the history of the market during the past few months. Reliable work, however, is steadily going 011 and it can confidently be expected that the methods will eventually be regarded in many regions as an essential part of the technique of securing geologic data needed for intelligent exploration.

Jan 1, 1930

By William H. Hallahan

The Friedensville zinc mine of The New Jersey Zinc Company is located about four miles south of Bethlehem, Pennsylvania in the Saucon Valley, an infolded and down faulted block of Cambro-Ordovician carbonate sediments surrounded by hills of pre-Cambrian gneiss and Cambrian quartzite except where breached by Saucon Creek at its entrance into the Lehigh River. The Beekmantown formation of lower Ordovician age is the host for zinc and limonite ores, the former occurring in the lower dolomitic portion thereof and the latter in the upper interbedded dolomite and limestone portion of the section. The Beekmantown is overlain unconformably by the Jacksonburg of middle Ordovician age and according to Miller (2) underlain conformably by about 2500 feet of Cambrian dolomites and 200 feet of the basal Cambrian Hardyston quartzite. Igneous rocks, younger than the Cambro-Ordovician carbonate rocks, are absent in the vicinity of the ore deposits. The major structure is a N60°E-trending saddle-shaped doubly plunging anticline overturned to the north. A syncline lies to the north of the anticline. A thrust fault of substantial displacement repeats the south limb of the anticline. The ore consists of sphalerite and pyrite, along with gangue dolomite and quartz, filling and replacing the sedimentary type matrix of a strata-bound solution collapse breccia in the dolomitic portion of the lower Beekmantown. This breccia was produced in pre-Jacksonburg time as a consequence of uplift, erosion, and development of a karst topography and subsurface drainage system in the Beekmantown. Deposits of both zinc and limonite are present on the vertical north limb, on the crest and on the gently dipping (25°) south limb of the Friedensville anticline; consequently, there is no preferred structural setting for mineralization. Rather this distribution supports the view that the folding is post-ore. Features confirming this view are the development of flow cleavage in the breccia matrix, the deformation of some of the sphalerite, and the fracturing of the pyrite mineralization therein. There is nothing to indicate that the age of mineralization is other than Ordovician and older than Taconic deformation. In the absence of intrusive igneous activity younger than the ore host, the writer suggests that submarine volcanic exhalations associated with the volcanic activity recorded in the eastern eugeosynclinal facies of the Ordovician may be the source of the metal ions.

Jan 1, 1968

By Thomas J. Crocker, Galen G. Waddell, Eugene H. Skinner

This paper describes a method of measuring initial and long-term deformations which occur in the medium surrounding mine accessways, and discusses the importance of this type of measurement in assessing support-problem areas. Delineated are (1) description of the rock-deformation monitoring equipment, (2) results of two field tests which monitored rock deformation around 4-foot-diameter raise bores, and (3) a numerical-analysis (finite-element) technique to correlate theoretical with experimental results. Instrumentation developed provided the sensitivity and resolution needed to measure rock deformation around a full-scale raise bore during excavation. Results of the tests conducted at the Lucky Friday mine, Mullan, Idaho, show the relationships between (a) de- formation vs. time, and (b) deformation vs. bit progress. Based on theoretical evaluation of the initial deformation, the medium appeared to behave elastically. Using an estimated field stress of 5,500 psi and Poisson&apos;s ratio of 0.20, the gross modulus of elasticity of the rock was calculated to range from 3.15 to 6.0 x 106 psi (with one outlier which was determined to be >12 x l06 psi).

Jan 1, 1971

By Albert J. Phillips

FOR the most part, recent changes in nonferrous physical metallurgy have been gradual and of a transition nature rather than abrupt modifications of existing methods. Development of new alloys containing vital constituents in what formerly would have been considered minute amounts has necessitated more precise control of metallurgical procedure than ever before. Realization of the remarkable effects of minute amounts of specific foreign elements in many alloys has brought about a revolutionary control in the selection of even the most commonplace raw materials. In addition, recognition of the widespread occurrence of precipitation hardness in metal systems, and the utilization of many of these, has emphasized not only the need for precise temperature control but also the necessity for considering the time factor in its effect upon properties in the treatment of most metals. These needs have caused the development and widespread installation of equipment that permits precision of control undreamed of a generation ago.

Jan 1, 1935

By Francis L. Bosqui

The following paper embodies a report which I made on the filter-press treatment of slimes at the Liberty Bell mine, Telluride, Colo. At the time this report was submitted, the management deemed it wiser to defer the installation of so costly a plant as the one required, in the hope that some of the many investigators in the field might soon evolve a cheaper and more perfect method of slimes-treatment, and one better suited to the conditions at Telluride. The Liberty Bell ore consists essentially of quartz and clay, with iron pyrites disseminated through the quartz in very fine particles. There is considerable iron and manganese stain in some of the ore, the latter especially in the clays, which are sometimes quite black. Occasionally particles of galena, zincblende, gray copper and a few other minerals are seen, but they are comparatively rare, and not in sufficient quantity to affect considerations of treatment. Free gold is occasionally seen in the quartz, and one or two instances of mire silver have been observed. The milling-plant consists of an 80-stamp amalgamating mill which crushes through 20-mesh screens; 20 Wilfley concentrating tables, taking out, in iron sulphides, about 2 per cent. of the total ore crushed; and a cyanide plant consisting of two tiers of 33 ft. vats, five in each tier, fed by revolving pipe-die tributers. The slimes overflow from the upper settling tanks through gates with adjustable outlets, and thence to a large canvas-plant, which efects only a small saving. This slimes product, of which about 100 tons escape per day (or 38 per cent. of the total ore crushed), contains about 3 per cent. of dry solids. Of this approximately 93 per cent. will pass a 200-mesh screen. The slimes range in value between $3.90 and $4.87 per ton, the values being about equally distributed between gold and silver. The actual averages for ore and slimes during the years 1900-

Jan 1, 1904