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By R. W. Davis

INTRODUCTION CHURCHILL river was named for John Churchill, first Duke of Marl-borough and third Governor of the Hudson's Bay Company, in the latter part of the 17th century, some fifty years after the ill-fated Danish expedition, led by Munck, had abandoned the site of the now famous seaport of Churchill, as a worthless, cold, disease-ridden country. No other attempts were made to explore the interior until the river basin became a part of the grant to the Hudson's Bay Company and began to play its part in furnishing the luxury of fine furs to civilized people as it had furnished the necessities of food and dress for untold centuries to uncivilized natives. This was the sole contribution of the region to the economic life of the country for some two hundred and fifty years, until 1926, when the power site at Island Falls was discovered by engineers seeking a cheap power source to make possible the development of the great ore-body at Flin Flon. DRAINAGE BASIN OF CHURCHILL RIVER The river is some 1,325 miles long. Rising in the headwaters of the Beaver river, in east-central Alberta, it flows in an easterly direction across Saskatchewan and northeasterly across Manitoba to Hudson bay, through a remarkable basin of some 115,500 square miles, only 6,000 square miles less than the area of the British Isles. A journey down this river leads one through three distinct belts of country, each vastly different from the others geologically and in surface characteristics. For the first five hundred miles the river flows through a basin of 36,000 square miles of the great central-plains country, which is covered with fertile soil and carpeted in its southern part with prairie grass, which gradually gives way to the mixed forests of poplar, spruce, birch, and jackpine in the northern and eastern sections: About midway across Saskatchewan, bald-headed knolls and ridges begin to make their appearance as the river meets the western margin of the Canadian Shield. Then, for some seven hundred miles, it passes through country underlain by the pre-Cambrian rocks of the Shield, which continue to within one hundred miles of Hudson bay. Here the character of the country again changes to a low, clay plain underlain by sandstone, and through this 'clay belt' the river flows between steep clay banks, to empty into Hudson bay.

Jan 1, 1935

By L. H. Cole

FOR many years Industrial Minerals, or as they were formerly called, 'the Non-Metallic Minerals', compared with the metallics, were considered of only minor importance and as such were given scant attention in the technical press as well as in the public press. Those days are, however, happily passing, and thanks, to an appreciable extent, to the constant endeavour of the Industrial Minerals Section of this Institute, established in the fall of 1932 industrial minerals are now assuming the importance to which they are entitled. The term 'Industrial Minerals', when first adopted in this sense by the Institute, was thought to be original in its application, but it is interesting to note that it had been used many years previously by the Queensland Geological Survey in the following publication: SALT Article 1 in Industrial Minerals by B. DUNSTAN, Chief Government Geologist (Publication No. 268, in Part) Queensland Geological Survey, Department of Mines, Brisbane 1920 In Queensland, however, the term embraced some of the metals as well as the non-metallic minerals proper. The lead furnished by Canada in this matter bore rapid fruit, and already the term 'Industrial Minerals' is widely used, not only throughout Canada but in the United States as well.

Jan 1, 1939

By J. M. Whiting

"North America has entered a period when greatly increased attention must be given to energy .supply and demand by government, industry and individuals. Such increasing concern about energy will be a long-term phenomenon, accompanied by continuing examination of future resource development and utilization. Those engaged in or associated with mining, a major energy consumer, are likely to experience a variety of problems which are associated with the end of an era of low-cost, virtually unlimited energy supply. Their efforts, furthermore, may be subjected to escalating public and government scrutiny, involvement and control. However, ever-growing recognition of the real and urgent necessity to systematically develop new energy supplies within Canada and the United States will provide unusual challenges and opportunities for those companies and individuals with mining expertise. The vast deposits of coal, tar sands and oil shale provide a relative certainty of supply which only stands to gain in attractive ness with time. In order to benefit from this aspect of certain supply, nevertheless, synthetic fuels will have to be produced at a tolerable cost. This will always require excellent process design and engineering. As synfuels development expands to any significant production level, however, and Jess than ideal reserves are scheduled, the usual geologic-productivity complexities encountered in making ore out of low-value rock will tend to become of prime concern. It is for this reason that the services of experienced mining personnel will be in growing demand in energy production."

Jan 1, 1973

By N. O. Lotter

The connection between mineralogy and metallurgical performance in a plant was recognised long ago (Gaudin, 1939; Petruk, 1976; Petruk and Hughson, 1977; Cabri, 1981; Petruk and Schnaar, 1981; Kinloch, 1982; Peyerl, 1983, Baum et al 1989 for example). The modern toolbox that we now routinely use for flowsheet development took decades to develop (Lotter et al., 2002; Baum and Lotter, 2004; Lotter, 2011 for example). Many workers contributed considerable time and effort to this overall mission of connecting sampling, mineralogy and mineral processing to integrate the flowsheet development activities. Certain key milestones marked this journey, such as Gy’s treatise on the sampling of particulate materials in 1979, which was later added to by François-Bongarçon, Pitard, Minnitt, and Holmes for example. The development of QEM*SEM by Gottlieb et al. of the MLA by Gu et al. constituted a huge leap forward in accuracy and mineral measurement capacity, as well as a reduction in standard errors of mineral characterisation. The advancement of the microprobe to an automated platform made a significant difference to detailed compositional mineralogy. This led to a strong position from which to draw meaningful processing implications from the mineralogical data. Reproducible flotation testing and reliable plant survey material for characterisation was dealt with by, amongst others, High Confidence Flotation Testing ( Lotter, 1995: Runge, 2010, and Bradshaw, 1997); and Statistical Benchmark Surveying (Lotter, 2005), with earlier prototypes which were steadily improved (Lotter, 1994; Restarick, 1976). The sterling work of Napier-Munn in engaging sound statistical methods with mineral processing led to the successful design and use of methods that could identify and quantify small recovery gains in plant scale trials. This history and present capability are reviewed, including leverage into asset management.

Jan 1, 2018

By J. E. Dutrizac, J. M. Zinck

Ferrihydrite is often the initial precipitate resulting from the rapid neutralization of Fe(III) sulphate solutions, and it seems to be a major constituent of zinc plant neutral leach residues. The most important parameters affecting ferrihydrite precipitaton are temperature, solution pH and the neutralization rate. Low temperatures and rapid neutralization rates yield poorly filterable ferrihydrite, whereas higher temperatures and slower neutralization rates produce readily filterable precipitates; in all instances, however, the precipitates are two-line ferrihydrite. Significant amounts of Zn are incorporated in the ferrihydrite precipitates, and the Zn contents increase with increasing Zn concentration, pH or temperature. Generally, the sulphate contents of the precipitates decrease as the Zn contents increase, and this may indicate that the Zn is adsorbed on the ferrihydrite. Discrete Zn phases were not detected. Neither Cd nor Tl is precipitated with ferrihydrite, although thallium jarosite co-precipitates with ferrihydrite at high Tl concentrations and elevated temperatures. Virtually all of the Sn added to the solution precipitates with the ferrihydrite, but the tin is believed to be present as intimately admixed amorphous SnO2.nH2O. Although selenite extensively precipitates with the ferrihydrite, selenate remains mostly in solution, likely because of the close similarity of the SeO4 2- ion to the SO4 2- ion which is present in high concentrations and saturates the available sites for anion adsorption.

Jan 1, 1998

By A. Y. Smith, R. J. Allan, E. H. W. Hornbrook, R. W. Boyle, W. Dyck

"HYDROGEOCHEMICAL METHODS in the Canadian Shield can be based on analyses of the following :(1) spring waters and their precipitates;(2) stream and river waters;(3) lake and muskeg waters;( 4) ground waters from drill holes, wells, faults, etc.;(5) waters issuing from diamond drill holes, faults, shear zones, etc. into mine workings and open pits; also analyses of precipitates associated With these waters.The first four can be utilized in both reconnaissance and detailed surveys. The last is suitable only for detailed work.For hydrogeochemical methods of prospecting to be effective, the following conditions must be present. 1. Natural waters must come into contact with mineral deposits and remain in contact with them long enough for the solution of detectible amounts of ore, gangue or indicator elements. 2. Dispersion patterns must be present in the hydrologic systems in order to trace the elements back to their source. These patterns may take the form of trains (e.g., increasing amounts of elements upstream toward t he source (s), Figure 1 ) or halos (e.g., increasing amounts of elements in bodies of water toward the source (s), F igures 2 and 3)."

Jan 1, 1971

By Karl J. C. Harries

"9.1. INTRODUCTIONIn Chapter 5 of Volume I royalties are dealt with and several topics would appear to be duplicated in this Volume. However, Volume I may be looked upon as a general guide, whereas this Volume is a reference volume. It deals in considerable detail with specific provisions and concepts relating to royalties between private parties. This does not, however, mean that Chapter 5 can be ignored. It should be looked upon as a source of general information concerning royalties between private parties and as a negotiating aid intended to give an overview of various topics. You may well find that in its general approach it will lead you to ask a question which, hopefully, will be dealt with in this Volume .It should be remembered that royalty agreements are agreements with a particular focus, and so the concepts set forth in Chapter 1 apply to them. This chapter addresses a few considerations specific to royalties that will usually form part of an agreement rather than a stand-alone agreement.9.2. FORMAT FOR ROYALTY PROVISIONSIn many of the cases where royalties arise, they are adjunct to, or part of, other arrangements. For example, a royalty may form part or all of the consideration to be given to an owner upon purchase of his property, or it may arise if a joint venturer ceases to contribute to the venture and has his interest converted to a royalty.1 It is with such situations that this section primarily deals; if the royalty is contained in an agreement that is singularly, or primarily, concerned with creating it, then it is just a normal agreement.Commonly, by the time the right to receive the royalty arises, at least some of the other provisions of the agreement have been performed and/or become redundant. For example, in an option agreement the royalty will be a continuing obligation of the optionee, usually arising only after the option has been exercised.2 In a joint venture agreement, a royalty will often arise where the interest of a non-participating venturer has been diluted and converted to a royalty, in which case the recipient will usually become a passive party, entitled only to his royalty, and most of the rights that he enjoyed as an active venturer will cease to be effective."

Jan 1, 2003

By L. S. Beck

"The Athabasca region forms part of the Churchill province of the Canadian Shield and is underlain by an Archean or Aphebian assemblage of rocks that underwent severe metamorphism and granitization during the Hudsonian orogeny (1750-1950 m.y. ago). In places, the eroded orogen is overlain by unmetamorphosed cover rocks (in-cluding the Martin and Athabasca formations) of probable Paleohelikian age. Basic dykes cut all the rocks of the region.There are innumerable vein-type pitchblende deposits and many syngenetic occurrences of uraninite in crystalline basement rocks. Evidence is presented to show that pitch-blende was emplaced during the final stages of the Hud-sonian granitization and followed the crystallization of syngenetic uraninite transitionally. In terms of P-T condi-tions, the pitchblende deposits belong essentially to Lindgren's mesothermal group.Based on the postulated uranium metallogenesis, the possibilities of finding further deposits of pitchblende and other types of uranium deposits are discussed."

Jan 1, 1970

By J. M. Ríos

"Without conscious effort and understanding, a number of factors unique to mineral exploration often hinder building sustainability in host communities. These include the episodic and transitory presence of an exploration team in the community and the inherent uncertainty of outcomes— most projects fail from an exploration perspective. Experience in rural communities across Mesoamerica, however, has shown that it is possible to go beyond pragmatic philanthropy and infrastructure improvements to promote positive, sustainable outcomes in communities. Examples are provided of lessons learned and proven practices that improve quality of life and support a strong social license to operate.RÉSUMÉ Sans une compréhension et un effort réfléchis, de nombreux facteurs uniques à l’exploration minérale nuisent souvent à l’établissement d’un développement durable dans les communautés d’accueil. Ces facteurs comprennent la présence épisodique et transitoire d’une équipe d’exploration dans la communauté et l’incertitude inhérente des résultats – la plupart des projets échouent après l’étape de l’exploration. L’expérience dans les communautés rurales à travers la Méso-Amérique a toutefois démontré qu’il est possible de dépasser la philanthropie pragmatique et les améliorations des infrastructures pour promouvoir des résultats positifs et durables dans les communautés. Des exemples qui améliorent la qualité de vie et soutiennent un solide permis social d’exploitation sont présentés; ils sont tirés de leçons apprises et de pratiques éprouvées."

Jan 1, 2015

By The Staff

BEFORE going into detail on the subject to be presented, a brief outline of the Company's earl y history would not be out of place. Prospecting and mining on a small scale was started in 1876 on the site of the present open pit at Thetford Mines. The property was purchased from the Crown in 1878 and Johnson's Company was incorporated in 1885. It is owned and operated today by descendants of the original shareholders. Many employees, through their fathers and grandfathers, have service records dating back three generations. The principal asbestos deposit at Thetford Mines is pear-shaped, with surface dimensions of about 2,200 feet in length by 1,300 feet in maximum . width. Its long axis strikes northeast and the dip is nearly vertical, but irregular in detail. It is known to extend to a depth 1,200 feet below the original surface, but its area at that depth has not been determined. Ownership of this deposit is divided among three active Companies: the Asbestos Corporation, Limited; Bell Asbestos Mines, Limited; and John-son's Company. Johnson's Company owns a section about 1,000 feet in length and 500 feet in width, bounded on the northeast by the King mine of the Asbestos Corporation and on the northwest by the Bell pit. On Johnson ground, there was originally a large outcrop o~ asbestos rock which dipped toward the south below overburden. This was mined until recently by open pit, the overburden being stripped off as far southward from the original outcrop as was economically possible. As the. pit was deepened, within side walls maintained at a maximum safe slope, its floor area, of course, became progressively smaller, and eventually the pit would have wedged out against the Bell property line. It became necessary, there-fore, to introduce some other method of mining before production became seriously curtailed by a shrinkage of the pit area.

Jan 1, 1941

By Marvin E. Lane

Viburnum, located in the foothills of the Ozarks in south-east Missouri, is the site of a modern lead mining and milling operation. Two mines are currently producing a total of 5,000 tons per day and a third mine is in the final development stage, with full production scheduled for late this year (1964). These mines will supply the tonnage required to keep the Viburnum mill operating at a full capacity of 7,000 tons per day for many years. The efficient underground mining operation is completely trackless. Drill jumbos are used to break the ore in a room and pillar method of mining. Transloaders, or St. Joe shovels, and trucks do the loading and hauling. The Viburnum mill has a world-wide reputation as a most efficient operation. This is due to the extensive use of automatic process controls, and labour saving materials handling facilities. Introduction THE St. Joseph Lead Co., has operated lead mines in southeast Missouri for 100 years. These operations have been confined largely to the area called the

Jan 1, 1964

By Rodney R. Koch

The phys ica l properties of gold should faci li tate its detection. However, the average concentration of gold in the ea rth's cru st precl udes the ability of geophys ical methods to detect the metal directly. In order to effectively pursue geophys ical detection and location of gold mineralization there must also be geological input - i.e. a model. This will lead to the selection of the appropriate geophy ical techn ique(s) in the fo llow-up programs. Interpretation of the fie ld survey data is of con iderable importance in expl oration geophys ics. Analytical techniques such as cont inuation, fi ltering, and spectral analys is, are now routinely empl oyed in the analys is of survey data to aid the interpretation process. The uccessful application of geophysical methods and the use processing techniques is demonstrated by two recent Saskatchewan discoveries. The first, the Star Lake 21 Zone, with reserves of 230,000 tons grading bener than 17.14 git Au associated with a disseminated sulphide quartz-bearing shear zone yielded geophysical anomalies that were distinctive, obvious, and would have lead directly to its discovery. The econd , the Laurel Lake Prospect, with ore grade intersections of 28.0I git Au and 52 .46 git Ag· over 5.49 m, resulted in numerous geophysical anomalies. However, none of these anomalies demonstrated association with the mineralization until processed results indicated that structural features crosscuning regional trends were important cont rol mechanisms for the mineral ization.

Jan 1, 1986

By E. Wraith, W. W. Culver, B. Wesstrom, P. J. Mackey

Electrodeposited copper of the 1860s was of unprecedented purity, although the profound significance of this achievement was not fully realised until the dawn of the electrical age a decade or so later. By the 1870s there were three somewhat large (4 to 4.5 tonnes Cu/day) electrolytic copper refineries in Germany based on J. B. Elkington’s process, first patented in the United Kingdom in 1865. More such refineries were planned throughout Europe. At the same time, copper output in the U.S.A. was starting to expand and with the spread of European electrolytic copper refining technology across the Atlantic, the door opened to major increases in North American output. The technology was first taken up in 1879 by James Douglas at the Chemical Copper Company in Phoenixville, Pennsylvania, where he was Superintendent. Douglas was assisted in this pioneering work by Edward Weston. The copper refinery at the Chemical Copper Company was small, not unlike the first plants in Europe. The present authors contend that the electrolytic copper refinery at the Chemical Copper should be regarded as the first copper refinery in the United States. The Balbach Copper Refinery in New Jersey, which commenced operations in 1883 with an initial production of about 2 tonnes Cu/day, has been erroneously considered as the “first commercial refinery”; it rightly belongs in second place. The early developments at these plants are discussed in this paper. INTRODUCTION In the mid-1800s, the main uses for copper were as sheathing on the wooden sailing ships of the day to protect from marine growth, boiler components in locomotives and steam engines, along with some construction uses. Copper ores were generally smelted, and further fire-refined for market. The recovery of gold and silver, if present in payable amounts, was a slow and relatively expensive step. This situation regarding copper would change by the 1870s with advances in the generation and use of electricity. The introduction of the dynamo led to major developments in electrorefining. First demonstrated in principle by Faraday in 1831 (Faraday, 1832), the dynamo was subsequently adapted and further developed by J.S. Woolrich for electro-metallurgical applications in 1842 (Woolrich, 1842; Napier, 1845). It provided a new source of power with the unprecedented potential to significantly change the scale of metal production by electrometallurgy. Interestingly enough, copper would be needed for the electrical age just beginning. By 1869, advances in dynamo design offered relatively reliable large machines, which enabled J. B. Elkington in the United Kingdom to use the dynamo in the radically new Pembrey copper electrorefinery — the first copper electrorefinery in the world (Wraith, 2013). Initial production at Pembrey was small — in the range of 1 to 2 tonnes/day — while gold and silver were recovered more readily by the treatment of the slimes than with methods used hitherto.

Jan 1, 2019

By P. E. Cavanagh

Introduction A comprehensive study of the economics of processes for smelting iron ores has been made by the Ontario Research Foundation on behalf of the Ontario Research Commission. This survey has included investigations of all processes in commercial use, and proposed processes which are still in the experimental stage. The two main objects of this work were to discover (l) whether any known processes would be particularly suited to present and future Canadian conditions, and (2) whether any new process would be of assistance in solving the present scrap shortage in Canada. The future prospects of the Canadian iron smelting industry have changed radically in the past ten years. For nearly twenty years before 1939 no iron ore was mined in Canada. The ore used was imported, mainly from the United States and Newfoundland. The economics of iron blast-furnace smelting always force the location of blast furnaces near the source of coal for making high-grade metallurgical coke, and near the market for iron and steel, rather than near the iron ore. Blast-furnace installations in Canada are confined to the north shores of the Great Lakes with ready access to United States coal and ore and the major Canadian markets, and to Nova Scotia near the coalfields of that Province. This distribution of primary smelting capacity naturally results in relatively high prices for iron and steel in the West, the North, and in Quebec.

Jan 1, 1948

By Willem P. C. Duyvesteyn

"Scandium International Mining Corp (SCY) has been involved in the commercial development of its Nyngan Scandium Project for about ten years. Various studies at a variety of global R&D organizations have been carried out in an attempt to define the deportment of scandium in both the limonite as well as the saprolite phases of Nyngan ore to assist with process development. Technologies such as sulfuric acid baking, high pressure acid leaching, sulfuric and hydrochloric acid atmospheric leaching and heap leaching have been extensively investigated both at the bench and pilot scale level to arrive at the most economic process flow sheet that will be discussed in some detail in this paper. Solvent extraction, ion exchange and other refining technologies have been tested and an optimum configuration has been established for the Nyngan project which is expected to be the first primary scandium mine and metallurgical plant in the world.Because of a lack of product availability the current scandium market is limited to less than 20 tons per year. Technologies have been identified to produce product with different specifications for aluminum alloys and solid oxide fuel cell applications. Preliminary economics have identified that Nyngan will be a robust and low capital cost project that can readily be expanded as the size of the scandium market increases."

Jan 1, 2016

By Arthur A. Cole

Although the metal silver has been known and prized from very ancient times, it is in the New World that the greatest silver camps have been found. This is shown in the following comparison: [] For the last few years, the World's annual production of silver has averaged about 240 million ounces troy. Of this total, the North American Continent contributes approximately three quarters, Mexico leading with 38 per cent, followed by the United States with 27 per cent, and Canada with nearly 9 per cent.[] Of the largest silver producers in Canada, the Sullivan takes first place. Although primarily famous as a lead and zinc mine, it produced, in 1926, more than 4.5 million ounces of silver. The Premier mine, in northern British Columbia, produced more than 3 million ounces. In Ontario, the largest producers in 1926 were the Nipissing mine, .with 1.9 million ounces, and the Keeley mine, with 1. 7 million ounces. The Mining Corporation produced 1.1 million ounces from mines in the Cobalt district proper, and an equal amount in South Lorrain; while from the Castle-Trethewey mine, in Gowganda, there was an output of slightly less than one million ounces.

Jan 1, 1927

By H. Marquis

The present paper consists of a survey of the literature on the problems of abrasion and wear of metals and materials by suspended matter. This problem is a very general one in industry, and is especially notice-able in the operation of cyclones and other types of dust collectors. The problem of abrasive dust in corrosive gas environments, such as commonly encountered in metallurgical industries, is particularly severe. Very little work has been done in the study of this type of abrasive wear, especially at high temperatures. However, a general review is presented here of all the work published on related subjects, such as that involving sand erosion in turbines and water wheels and the effect of temperature on friction wear. Topics in this paper include: blasting wear by sand, quartz, limestone, silicon carbide and other refractory particles; methods of investigation; effects of velocity, temperature and *Canadian Armament Research and Development Establishment, Valcarter, P.Q. angle of attack; correlation between indentation hardness, scratch hard-ness and resistance to abrasion; the effect of protective coatings; resistance of various metals; etc.

Jan 1, 1962

By T. Narita

The diffusion barrier coating system (DBC system) was designed to suppress interdiffusion between alloy substrate and coatings in addition to ensuring slow oxide growth at high temperatures. In this report the concept of the DBC system will be introduced, and the results obtained for various heat-resistant alloys are presented. In this DBC system the s-phase of the Re-Cr-Ni system was selected as the barrier and is formed by electroplating Re-Ni and Ni films from aqueous solutions, followed by Cr and/or Al pack cementations. A typical DBC system consists of Ni-base superalloy / triple s-Re based alloy layer / ?’-Ni3Al and/or ß-NiAl (with or without Pt addition) / a-Al2O3. It was found that the DBC system maintained its structure for long time exposures because the s phase has tie-lines with the ? and ?’ alloy substrate and the ?’ and/or ß coating. The s-Re based alloy can suppress both the inward Al diffusion and the outward diffusion of alloying elements. The DBC system was successfully applied to various heat-resistant alloys such as Ni-Mo and Fe-Cr-Al based alloys, and these alloys with the DBC system were creep-deformed slowly under external applied stresses. A simultaneous diffusion coating process for Al and Hf was developed using Hf+NH4Cl+Al2O3 pack cementation. To obtain reliable and long-life coatings the combination of alloy substrate, coating, and external scale should be considered as a total system, to optimize oxidation resistance, structural stability, and mechanical properties.

Jan 1, 2010

By Robb. V. M., F. Walraven, L. J. Robb

"Abstract -The old Albert Silver Mine is a polymetallic deposit comprising concentrations of Cu­ Pb-Zn-Ag-U-F within a set of sub-parallel quartz-hematite veins which occur within the fine-grained apical phase of the 2050 Ma old A-type Bushveld granites. Mineralization occurs as an early pyrite­ chalcopyrite-arsenopyrite-galena-sphalerite-(argentiferous) tetrahedrite paragenesis followed by a later, more oxidized assemblage comprising chlorite-hematite-fluorite-pitchblende. Accumulation of metals appears to have taken place at the interface between a coarse-grained porphyritic granite and an overlying fine-grained phase: veins occur in the latter and represent leakage of magmatic fluids from the differentiated, water-saturated, subjacent granite.Mineralization processes in the Bushveld granites are believed to be related to long-lived circulation of dominantly magmatic fluids stimulated by the high heat productive capacity of the host rocks. Endo- and exogranitic tin-tungsten and base metal mineralization formed during an evolving hydrothermal system that lasted for several hundred million years, forming innumerable small- to medium­ scale polymetallic deposits. At the Albert Silver Mine, unroofing of the cover sequences at circa 1600 Mato 1700 Ma resulted in the incursion of lower-temperature, high-f02 meteoric fluids which remobilized the earlier sulfides and introduced the paragenetically late U-F mineralization ."

Jan 1, 1994

By W. E. Kuhn

Introduction The work, of which some of the results are described in this paper, was started with the object of investigating the properties of certain binary alloys of titanium made from powders. Our main interest was in the possible use of such alloys in gas turbines. We were attracted to titanium, as have been others, by its high melting point (I,724° ± 11°C.), its low density (4.54), and the likelihood that, if a relatively wide use could be found for the metal, it might become available in commercial quantities at a fairly reasonable price. The readiness with which the metal reacts with hydrogen, oxygen, and nitrogen was recognized from the very beginning. At the same time there seemed a good chance that alloys could be produced which, because of the formation of protective films, would resist the attack of these and other corrosive agents. No specifications were drafted to cover the 'quality' of the titanium hydride powder which was used in our work and which was, to judge by the results of a few preliminary experiments, the most useful source of titanium then (1944) available in sufficient amount for our purpose. During the course of our work, the need for such specifications became very clear (see Sections 9 to 12 of this pa per). Even today, lack of knowledge regarding the effects on titanium of impurities, some of which may later be looked upon as essential elements in commercial alloys of titanium, and difficulties in manufacture, make the preparation of specifications for commercial titanium and titanium compounds a doubtful procedure. The papers presented at the 1948 Symposium on Titanium, sponsored by the U.S. Office of Naval Research lend colour to this view. At the time our work was commenced, one had to depend upon the manufacturer to supply what he considered to be his 'best' material. It may be some time before we can ask for more than this, the question as to what is his 'best' being left to the manufacturer to decide. However, in this connection the results of our study may be of some value and on that account we are constrained to publish them.

Jan 1, 1950