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By Wm. I. Weisman, C. W. Tandy

Consumption of fluorspar in the United States in the last ten years has doubled to 1.34 million tons. One main, reason for the increase has been the use of the basic oxygen furnace to produce steel which requires considerably more fluorspar than the open hearth. The increasing consumption of aluminum and fluorocarbon chemicals will require more fluorspar, Since 1964 domestic fluorspar prices have advanced over 70%. Maximum prices were attained in 1971 and remain stable. These higher prices have brought about the expansion of production capacity at many of the present mines and mills. Exploration has been intensified, resulting in new discoveries, which are being brought into production. Many deposits, heretofore considered uneconomical, are being reappraised for possible development. Companies who have not previously mined fluorspar are actively seeking and acquiring new properties. The outlook for the continued health of the domestic fluorspar industries is favorable at present prices; however, it is doubtful that production will be greatly increased. New production will have to come from presently inaccessible areas of much greater distance from consuming centers. Prices will have to be higher to support this production. Domestic fluorspar production meets only 20% of domestic consumption. Thus, reliance on imports on fluorspar in the future will become increasingly more critical.

Jan 1, 1975

By Philip W. Guild

Approaching exhaustion of areas where traditional prospecting methods can pay off and sharply rising costs require increasing sophistication in planning exploration. Most outcrops, not only of ore and gossan but also of obvious zones of alteration, have been examined; many of the anomalies readily detectable by geophysical means have been drilled; geochemical surveys now cover extensive tracts. How should the explorationist proceed to find the ores that will keep his company in business and supply the world with the energy and raw materials it needs? Two courses are open to him: (1) saturation coverage by geology, geophysics, geochemistry, and drilling in the expectation that something will turn up or (2) critical analysis of the factors responsible for the concentration of valuable minerals in the earth's crust. The successful explorationist applies both methods to the limit of his resources. The second course, analysis of geologic factors, also comprises two principal lines of research: (1) ever more detailed study of the chemistry (including isotopic analysis) of the ore and gangue minerals of known deposits in an effort to understand how they were formed and (2) increasingly detailed mapping of their environment to determine the reasons for their localization. Again, both are very necessary.

Jan 1, 1971

By L. M. Johnson, C. G. Janes

INTRODUCTION In May, 1966, the General Services Administration (GSA) announced a program to encourage additional domestic production of copper in the interest of national security. Upon learning of the copper production expansion program, Duval Corporation entered into negotiations with GSA for development of the Sierrita copper-molybdenum property under the program. Agreements between the GSA and Duval Sierrita Corporation, a wholly owned subsidiary of Duval Corporation, were concluded in 1967, with the Sierrita Concentrator beginning operation in 1970 at a designed capacity of 72,000 STPD. Subsequent additions and modifications have expanded capacity to 90,000 STPD. This property, located approximately 20 miles south of Tucson, Arizona, represents an investment including working capital of about $200 million. These funds were provided from an $83 million loan from GSA, repayable in copper valued at 38 cents per pound, $48.75 million of bank loans subject to U. S. Government V-loan guarantees, and Company capital contributions. Current general operating statistics for the concentrator are listed below: [Ore Grade 0.32% Cu., 0.030"/. Mo. Daily Tons Milled 90,000 STPD Annual Copper Product ion 94,600 Tons Annual Molybdenum Production 15,000,000 Lbs. Annual Silver Production 1,135,000 Ounces]

Jan 1, 1976

By E. H. Bronson

PROPERTY of Malartic Gold Fields Ltd. is situaated in the great clay belt in the northern part of the Province of Quebec. This belt represents the floor of the glacial lake Barlow-Ojibway. The clay blanket has a gently rolling, almost flat surface, with here and there projecting knobs and ridges that outline the large irregularities of the surface on which the clay was deposited. At irregular intervals glacial eskers dominate the landscape. The ore-bearing country rock is covered by strata of clay, sand, and silt to a depth varying to 40 ft. There are serious structural problems when it is necessary to place loads of unequal intensities on this surface to support buildings and machinery for a modern mining plant. Earlier mining companies and their engineers paid little attention to the science of soil mechanics, partly because they believed it unnecessary and partly because they knew little of the subject. The results are evident in some of the tottering structures in older camps. Careful analysis of soil problems is well worth-while, since cost of foundations may vary from 20 to 50 pct of the final cost of a structure. Low operating and maintenance costs can be achieved only in this way.

Jan 11, 1957

By George F. Weaton

Mining differs from the ordinary industry in that most industries and enterprises have an indeterminate life, apparently perpetual, and therefore, are not called on to replace the original investment. In mining, however, when the ore bodies are mined out, there is nothing left, The original capital investment must, therefore, be returned to the investor by the time that the profitable life of the mine is ended. When the operating company makes no provisions for perpetuating its life by investing a portion of its earnings in other properties, the usual procedure is to pay the investor, periodically, a dividend sufficiently larger than the risk return on his investment to enable him, if he reinvests this overplus at a safe rate of compound interest, to replace his original capital by the time the mine is exhausted. This overplus constitutes a return of invested capital. In estimating the value of a mining enterprise, the work leading to the final result may be divided into two parts. The first is the examination of the property to determine ore reserves, mining costs and profits, financial requirements and future prospects. Whatever conclusions are reached in this phase of the work depend on the experience, thoroughness and integrity of the examining engineers. The second is the calculations pursuant to the field examination.

Jan 5, 1973

By Norman C. Britz, Mortimer P. Buck

THIS PAPER DEALS WITH the practices used at the Huntington, Nest Virginia works of The International Nickel Company, Inc., in hot and cold rolling nickel and high-nickel alloys. The practical metallurgical aspects are discussed and a brief description of equipment given. The alloys covered may he divided into three main groups. based on their major constituents: 1. Nickel alloys, 2. Nickel-copper alloys. 3. Nickel-chromium alloys. The nominal compositions of the various alloys which are produced in most common mill forms are given in Table 1. Nickel, a commercially pure grade of nickel containing about 0.05 pct carbon as' the chief alloying element, is produced in all common Mill forms. "L" Nickel is commercially pure nickel in which the carbon content is held as low as possible, usually less than 0.01 pct. This grade of nickel is used chiefly for spinning and for special high temperature applications where its low carbon content enhances its corrosion resistance. "D" Nickel contains 4.5 pct manganese to provide improved resistance to sulphur embrittlement at elevated temperatures. "Z" Nickel is an age hardening grade of nickel containing carbon, aluminum, and silicon as the age hardening elements. This alloy combines the cor-

Jan 1, 1948

By J. J. Rutledge

I. DESCRIPTION OF THE CLINTON ORES AND ASSOCIATED POCKS. THE Clinton rocks in Stone Valley comprise (1) thick layers of deep-red shale, (2) layers of reddish-gray shale interspersed with beds of sandstone and thin beds of extremely fossiliferous limestone, and (3) yellowish-gray shales alternating with thin layers of olive-colored shales. These layers of shale are all very thin and are at no point massive.1 A bed of gray-white sandstone varying in thickness from 12 to 30 ft. occurs in the tipper portions of the Clinton shales. This is called the ore sandstone, a name given to it by Rogers and adopted also by the Second Pennsylvania Geological Survey. It is the surest guide to the presence of the iron-ore bed, which lies below its lower edges at distances varying from 10 to 20 ft. This ore sandstone, in the valley, lies generally at very low inclinations, but often is locally subjected to considerable changes in dip. At its outcrop this ore sandstone weathers very easily and yields a rather sparse crop of stone, Composed of dirty, iron-stained boulders. Upon the roads these boulders are quite well rounded, and bear fragments of crinoid stems and other fossil forms. The ore sandstone exhibits at many points evidences of former movements in this very great thickness of the shales, and as it is the only stratum in this series competent to transmit and record stresses due to structural movements, its evidence is of considerable importance in determining the occurrence of movements in times past.

Nov 1, 1908

By Edwin B. Wilson, Charles F. Cockrell

The application of evolutionary operation is proposed for the cleaning of coal by the heavy media process. Analysis of the data given suggests some benefits that may not be immediately appreciated unless evolutionary operation is applied. For example, while it may seem obvious to increase specific gravity when the ash and sulfur content of the clean coal is lower than that allowed, evolutionary operation may show that an increase in feed rate or an increase in both feed rate and specific gravity would be a more profitable alternative. In addition, by using evolutionary operation, up-to-date knowledge of the effect of change of feed rate or specific gravity on yield and product quality is available. This information facilitates confidence about decisions made in regard to the day-to-day operation of these units. A number of other applications in the minerals industry are proposed. An application of evolutionary operation in a related field is also given where a large number of variables were required to be optimized.

Jan 1, 1969

By Robert F. Shurtz, William J. Verner

Three basic questions must be answered by an engineer performing an economic analysis of a mineral property: (1) How much can the company afford to pay for the property; (2) At what rate should the property be mined; (3) What will be the return on the investment. These questions often defy reasonable analysis, because at the point in time at which they must be answered little may be known about the grade of ore and the reserve tonnage. The purpose of this report is twofold. First, to derive a method of determining purchase price, rate of production and return on investment which is valid under varying conditions of ore grade and tonnage reserve; and, second, to apply this method to the Margay deposit in an attempt to evaluate it as a business enterprise. This is an actual economic analysis of an existing nickel-copper deposit fictitiously named the Margay. It was carried out for a mining corporation and proved to be the determining factor in the subsequent purchase and development of the property. All data referring to costs, quality and quantity of ore, etc., are accurate and truly represented. Prices used are obsolete but the method is not dependent on those variables. Basic assumptions for the analysis are given in Table I, page 71.

Jan 11, 1966

By C. McLean, Erickson, S. G. Kolb, S. C. Moore

The Grossschloppen vein-uranium deposit, Bavaria, West Germany, was examined with underground workings during 1980-82 by Esso Erz GmbH, an affiliate of Exxon Minerals Company (EMC). Geologic evaluation entailed dense drilling of a portion of the deposit from workings constructed specifically for the program. Discovered in 1977, the deposit was initially explored by surface diamond drillholes which allowed definition of a 30-60 m wide vein system discontinuously mineralized along a 1000 m strike length and to at least a 450 m depth. The underground program was conceives as a cost-effective procedure to answer quest ions on vein correlation, grade continuity and variability. A 1200 m decline allowed access for detailed sampling of approximately 10% of the known area of mineralization. Fanned drillholes, logged by gamma probe, were spaced to provide intersections of veins at 10 to 20 m intervals. Six cross-cuts also penetrate the pitchblende and uranophane mineralization which occurs in 0.1 to 2.5 m thick quartz veins. Detailed cross-sections and level plans were constructed for resource estimates of the intensively studied portion of the vein system. The program resulted in the discovery of local, high grade areas and an average grade in the evaluated area nearly double that expected from surface drilling.

Jan 1, 1984

By H. W. Gillett

Unlike most previous Howe lecturers, I had not the good fortune to be associated with Henry Marion Howe, nor to be directly one of his students. Yet, through his writings, he has been my teacher, as he has of all American metallurgists. Instructive as his writings are—I use the present tense because Howe thought so keenly and reasoned so surely, seeing clearly, as if by intuition, what was hazy to lesser minds, that his writings are still vital—it is not those books and papers, nor even the minds he trained in his classes, that were his most outstanding service. It was the spirit of Howe in his approach to the problems of metallurgy, his broad-mindedness and fairness, his recognition of the need for theories and hypotheses to explain metallurgical phenomena, his willingness to use them as servants, as well as his questioning attitude—his refusal to accept them as masters—that comprise his greatest service. This most thoroughly warrants the honor the Institute pays each year to his memory. These traits I so respect and honor in any man that I glory in this opportunity to do reverence to him in whom they were so notably united. Howe's Discussion of a Creep Problem I have often wished that Howe were still with us to turn his keen insight upon the problems of the use of metals at high temperatures, a field much studied but still very hazy. Indeed, 53 years ago, in a paper1 before this Institute, Howe stated a problem closely allied to some that still perplex metallurgists and engineers dealing with the high-temperature field. Howe was intrigued by a report2 from another old master, Robert Henry Thurston, on the behavior of annealed vs. cold-drawn iron wire, and in order to broaden the foundation for metallurgical generalization, Howe made experiments of his own on copper and silver. In these tests by Thurston and by Howe, the wires were rapidly loaded to determine the

Jan 1, 1939

By Raymond F. Gray, Victor J. Hoffman, Richard J. Bagan, Harold L. McKinley

The first indication of tungsten in the Bishop area was the discovery of scheelite concentrations in a gold placer operation in the ( since named) Tungsten Hills in 1913. After early intermittent production, the deposits of the district were slowly discovered and developed. The Pine Creek mine, located in 1916 and under the direction of Union Carbide Corporation since 1935, became the principal producer in the district. By the end of 1965, the total production of the district had reached 3,450,932 units of WO3, 17,071,242 pounds of molybdenum, and 19,599,110 pounds of copper. The topography of the district is characterized by its extreme relief, ranging in elevation from 13,986 feet to about 4400 feet in the Mount Tom quadrangle. The present topography is the result of the uplift and erosion of the Sierra Nevada and the great subsidence of the Owens Valley with its related deposition and volcanism. The general structure of the pre-Tertiary rocks consists of a series of tightly-folded metasedimentary and metavolcanic rock remnants surrounded by exposed plutons ranging in composition from hornblende gabbro to alaskite. The metasedimentary rocks consist of low- to intermediate-grade metamorphic equivalents of fine-grained sediments deposited during the Paleozoic era in a miogeosynclinal environment. Later volcanics were deposited in a eugeosyncline. The ore bodies in the Bishop district consist of scheelite-bearing tactite formed by the pyrometasomatic replacement* of calcareous sediments along the contact with an acidic granitic intrusive. A number of the metasedimentary remnants have had tungsten deposited along their edges.

Jan 1, 1968

By George L. Atwood, William Brown

Phosphate ore is being mined at Monsanto Co.'s Henry mine, near Soda Springs, Idaho, for the company's three furnace elemental phosphorus plant near Soda Springs. The finished product from the furnaces is elemental phosphorus which is subsequently used in the manufacture of detergents, food preservatives, fire retardants and other consumer items. In stripping and mining, D-9 crawler tractors are utilized to rip and push-load rubber-tired scrapers. The equipment consists of six D-9G crawler tractors, four Caterpillar 657B scrapers, eight Euclid S-24 scrapers, one Reich T750 drill and one Caterpillar No. 16 patrol plus various support equipment. Stripping is performed on a 12- month basis, two shifts per day, whereas mining is mainly in the summer months on a one-shift basis. The hauling season begins May 15 and ends November 1 due to freezing weather and snow conditions. Annual production is 1 million tons of phosphate rock and 2.5-3 million cu yd of stripping. Stripping, mining and hauling is performed for Monsanto by Dravo-Soda Springs, a mining contractor which owns, operates and maintains all equipment used. The contractor is paid for stripping by the bank yard and for ore mined and hauled on a tonnage basis.

Jan 8, 1972

By William Kelly

An extensive swamp covers a large part of the town-site of Norway and adjacent laud. Through this swamp run two parallel oreformations. In the north one is the Aragon mine. The south one passes into the swamp on the Harrison property. On the edge of the swamp, about 1000 feet from the Aragon mine, a diamond drill, in the fall of 1889, located the ore-bearing formation and a probable ore-body. To explore further and develop this ore, the Penn Iron Mining Company proposed, in the spring of 1890, to sink a shaft. The drill had shown the depth of the glacial drift to be more than 60 feet. A test-pit near the location of the proposed shaft had struck, at a depth of 20 feet, an amount of water which a 200gallon pump was unable to lower. At the Aragon, a few years before, a shaft had been sunk to hard pan with great difficulty and many delays by the usual method of driving laths. Under the conditions it was decided to sink a caisson- or dropshaft. Two 40-horse-power boilers, a Lidgerwood engine with 4foot drum, and a good derrick were set up; and two No. 10 Kuowles

Jan 1, 1892

By D. D. Pollock, D. I. Finch

Relationships between the compositions of specially prepared manganin-type alloys and some of their electrical properties have been established. Empirical equations, based upon the electronic configurations of the alloying elements, are given which describe the resistivity, temperature coefficient, peak temperature, and thermoelectric power of Cu-Mn-Ni-Fe alloys at approximately room temperature. Calculations based upon these relationships are correlated with experimental data. SECURING suitable alloys for the construction of stable resistors, for use in precise electrical measuring devices, has been important ever since the art of electrical measurement was begun. German silver, Pt-Ag, and Platinoid are examples of some of the alloys in early use. These early alloys were un- satisfactory for one or more of the following reasons: l—insufficient stability of electrical properties with time, 2—poor reproducibility of electrical characteristics from melt to melt, 3—excessive temperature coefficients of resistance, and 4—excessive cost. Weston introduced the Cu-Mn-Fe and Cu-Mn-Ni-Fe alloys of the type now generally known as manganins. His patents are believed to represent the first disclosure of any alloy with a negative temperature coefficient of resistance. After this work, the German company, Isabellenhutte, in conjunction with Feussner and St. Lindeck, produced alloys of

Jan 1, 1957

THOSE NOT MARKED ARE MEMBERS; MARKED THUS t ARE ASSOCIATES. HEAVY-FACED TYPE SIGNIFIES HONORARY MEMBERSHIP. JUNIOR MEMBERS ARE MARKED II. THE FIGURES AT THE END OF THE ADDRESS INDICATE THE YEAR OF ELECTION. AARONS, J. BOYD, Genl. Mgr., Chaffers G. M. Co., Boulder City, West. Australia. '05 ABADIE, EMILE R., Min. Engr Box 291, Porterville, Tulare Co., Cal. '76 ABBOTT, CLARENCE E., Genl. Supt., Iron Mines Div., 1405 Minnesota Ave., Bessemer, Ala. '04 ABBOTT, J. W., Min. Engr., "St. Omer," 123 N. Grand Ave., Los Angeles, Cal. '94 ABBOTT, Louis BENJAMIN, Chief Engr., Consolidation Coal Co., Elkhorn Div., Jenkins, Ky. '15 ABBOTT, ROBERT R., Met. Engr., Peerless Motor Car Co., Cleveland, Ohio. '12 ABE, ASAKA Yamagano G. M., Satsuma-Gori, Satsuma, Japan. '14 || ABRAHAMS, A. I., Student 1391 Madison Ave., New York, N. Y. '14 tACKER, E. O'C., Met Bethlehem Steel Co., Bethlehem, Pa. '86 ACKER, Louis K., JR., Min. Engr 565 Highland Place, Bellevue, Pa. '08 ADACHI, JINZOO 11 Shiba Park, Shiba-ku, Tokyo, Japan. '88 ADAMI, C. J., Min. Engr., St. Joseph and Doe Run Lead Companies, Bonne Terre, Mo. '12

Jan 1, 1917

By Robert A. Kinzie

PAGE Introduction.............334 Climate.............335 History............335 Geology.............341 Mining..............343 Shafts............343 Stations and Ore-Bins....345 Levels. Drifts. Cross-Cuts, Winzes. etc........347 Stoping Surface-Pits,......... 351 Underground Stoping........... 332 Chutes. Drilling. etc.....354 Tramming............. 358 Sampling. Maps and Assaying.........360 Labor.............361 Machinery.............362 Milling,..............362 Crushers.............366 Battery-Foundations...........368 Power (Water—Coal)...........373 Methods of Catching the Free Gold...374 Screens..............376 Apron-Plates,.......376 Concentration..........378 Clean-Up,.............378 Labor..............382 Costs..............382 Introduction. The Treadwell Group comprises five mines. four of which are situated on the northeast side of Douglas island. directly opposite the town of Juneau, and one about four miles back of Juneau. These mines are owned by four separate companies. but are all under the same general management. Those situated on Douglas island are : The Treadwell mine. owned by the Alaska Treadwell Gold Mining Co.. the Mexican mine. owned by the Alaska Mexican Gold Mining Co.; and the Ready Bullion and Seven-Hundred-Foot mines. owned by the Alaska United Gold Mining Co. The Juneau mine. owned by the

Jan 1, 1904

By Alfred F. Brainerd

There has been no enterprise undertaken in this and adjoining States which has attracted so much interest, or has been watched so closely as this, the first successful attempt to convert our ordinary high-phosphoric pig-iron into steel from native material. Our iron-masters have noticed intently every attempt to convert high-phosphorus pig-irons into steel by the Clapp-Grifith process in this country, and the basic process on the Continent, and studied the various patents aiming to accomplish the same purpose, and the various litigations arising among various patentees over their rival claitns; but up to August, 1887, nothing was done, and no move had been made to introduce any process for making steel. At the time above named, Mr. James Henderson, of New York, came to this place with a view of introducing his patent furnace and other metallurgical processes and appliances. After some delay and personal interviews between parties interested and the inventor, a party of gentlemen, all of moderate means, and entirely unacquainted with the manufacture of either steel or iron, decided to form themselves into a body corporate, known as the Henderson Steel and Manufacturing Company, with a capital stock of $20,000,

Jan 1, 1889

By Stephen Birch

THE Chitina mining district of Alaska is located at the headwaters of the Chitina and Copper Rivers. At present, the only producing min-ing properties are the mines of the Kennecott Copper Corpn. and the Mother Lode Coalition Co., which are situated 196 miles from Cordova the port of entry. The first claims, later acquired by the Kennecott Mines Co. and afterwards transferred to the Kennecott Copper Corpn., were discovered in 1900. The Copper River & Northwestern Ry., which connects the mines with tide water at Cordova, was completed in the spring of 1911. Contemporary with the construction of the railroad, aerial tram equipment was brought to the mines by pack train and a tramway, 3 miles, long, connecting Bonanza mine with the proposed railroad terminal, was finished, enabling shipments of high-grade ore to be made immediately on the completion of the railroad. A mill to treat the lower grade ore was begun the same year. The Kennecott company's holdings consist of 111 mineral claims. The Mother Lode Coalition Mines Co., which is controlled by the Kennecott Copper Corpn., owns 73 claims adjoining the Kennecott holdings. All data on operations and geology refer equally well to the Mother Lode property.

Jan 1, 1924

By George F. Kunz

Jan 1, 1902