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By Eldon C. Pattee

Variations of a very reliable geochemical field test for beryllium developed by Patten and Ward, have been adapted by the U.S. Bureau of Mines to facilitate rapid testing of reconnaissance samples and to aid in rapid examination of known occurrences. Although several qualitative tests for detecting beryllium have been described in the literature,1,2,3, the Patten-Ward4 morin geochemical field method has the advantages of being rapid and being quantitative for minute amounts of beryllium. In addition to the morin field method, Patten, in cooperation with Griffitts, have developed a contact- print method for determining beryllium in hand specimens.5 The semiquantitative method can be used for rapid screening of samples in exploration or reconnaissance work. The use of beads for fusing samples provides a more rapid test, but gives less accurate results than the method developed by Patten and Ward. The semiquantitative method, however, requires less equipment and combines three stock solutions into one reagent for easy application. Estimates of samples in the range from 3 to 1000 ppm varied from about 0.25 to 5 times the actual beryllium content.

Jan 5, 1965

By F. P. Haver, M. M. Wong

When a mixture of chalcopyrite concentrate and lime is heated in air, the following reaction takes place: 2CuFeS2 + 4Ca (OH)2 + 8 ½ 02 ; 2Cu0 + Fe203 + 4CaS04 + 4H20. Ca (OH)2 is the only common reagent that will adequately control SO2 evolution in roasting. Other additives tried, including CaO, CaCO3, Na2CO3, NaOH, MgO, Mg (OH)2, and MgCO3, were not effective. All reacted with sulfur, but not to the extent that will be required to meet the new control regulations for sulfur oxide emissions. For example: when the concentrate was heated with the theoretical amount of limestone (CaCO3), about 55% of the sulfur was retained in the calcine; whereas use of the stoichiometric amount of Ca (OH), converted approximately 99% of the sulfur to CaSO1. In most of the experiments, Ca(OH)2 was formed by adding CaO to concentrates containing enough water to simulate filter cake from flotation circuit. This eliminated the need for drying the concentrate and utilized the heat of hydration of CaO.

Jan 6, 1972

By E. J. Hammer

Crushing and grinding of gypsum demands con- trolled processing to a fineness suitable for further treatment of the mineral into end products, and into various sizes of material which are themselves saleable products. The majority of gypsum tonnage ultimately ends up in stucco for wallboard. Therefore, mineral reduction is normally designed toward this end, but it is done in a manner that permits drawing off intermediate products to meet various customer requirements. This forces companies into compromises at times in equipment installations. Normally, 5 to 6 different sizes intermediate to the end product are marketed and these are generally the fineness of material to be used as stucco for wallboard. These sizes are produced by controlled crushing, grinding and sizing. How Ore Characteristics Guide Processing First, gypsum as a mineral (CaS0;2H,O) is number two on the Mohs scale two of hardness; only talc is softer, Despite being soft, gypsum is tough, a factor which is of critical importance when developing equipment specifications. In addition, of the increasing volumes of rock handled, the associated and included impurities such as anhydrite, silica or lime- stones are found to be relatively abrasive.

Jan 1, 1970

Discussion of the paper of Blarney Stevens, presented at the Butte meeting, August, 1913, and printed in Bulletin No. 79, July, 1913, pp. 1285 to 1303. F. L. GRAMMER,Leesburg, Va. (communication to the Secretary*):¬ Mr. Stevens refers to an explanation of parallel jointing by W. 0. Crosby, which I noted when reading one of his excellent text books. It seemed to me earthquakes were not a satisfactory explanation, and I looked up several authorities; but I never realized how small the usual amplitudes were until Mr. Stevens presented his paper. Several letters to the U. S. Geodetic Survey showed me there were very few records of tidal movements of earth crust in the United States. Altitude and latitude would be influencing factors; but this diurnal movement must exceed earthquake amplitudes, besides being more nearly universal. My inquiries brought the answer that the major directions of jointing had not been extensively tabulated. If major directions of jointing were recorded-with notes as to angle with mountain chain, or North Star, and distance between joints, with nature of rock and maximum and minimum tidal up-heaval-some interesting relations might be made manifest.

Jan 11, 1913

By Robert L. Russell, Henry W. Zimmerman

The Bunker Hill mine in the Coeur d'Alene mining district at Kellogg, Idaho, has been a major producer of Pb-Ag-Zn ores since its discovery in 1887. The mine has produced over 29 million tons of ore from some 20 to 25 veins and ore zones and now covers an area approximately 1 mi long by 0.5 mi wide. The active section of the mine extends from 2500 ft above sea level to 1600 ft below sea level. Ore production is presently at the rate of about 1700 tpd. A 2-mi adit, the Kellogg tunnel, at the 2500 elevation provides access to the main shaft area. Ore is hoisted to the adit level through a 5000-ft. 50º-inclined shaft extending to the lowermost haulage level 1200 ft below sea level. Primary shaft service for men and materials is supplied by three major internal inclined shafts equipped with double-drum hoists. Present production requires ten levels to serve for main line track haulage. These range up to 5000 ft in length and are either 200 or 400 vertical ft apart. Also, many intermediate levels exist throughout the mine.

Jan 1, 1971

By R. W. Jenkins

TRACKLESS equipment is being used by the Coplay Cement Manufacturing Co. to develop a folded limestone deposit economically and safely with inexperienced men. Cost and quality of development stone results in a saving when it is used in- stead of outside sources of limestone. This favorable cost has been attained by following a methods development and training program described in this paper. It is expected that further savings in favor of the mined stone will be made when stopes now being prepared are in production. The present equipment will be used for loading from stope draw points. The limestone is blended with quarried cement rock to serve as raw material for Portland cement, first produced in this country by Coplay Cement Manufacturing Co. from a process developed by its president, David 0. Saylor, in 1873. For many years the cement rock alone or with a small amount of added limestone was used for raw materials. Later as specifications were raised and the richer portions of quarries were depleted, limestone from outside sources was required in increasing amounts. In 1925 D. J. Uhle, the general manager, began to prospect company property for limestone.

Jan 1, 1954

By A. U. Seybolt

DURING the course of an investigation of hot corrosion of nickel-base superalloys (combination oxidation-sulfidation attack at high temperature), it was considered possible that sulfur might gain entrance to the alloy in part, at least, by diffusion through the scale. Cr203 is nearly always observed as a prominent component of the oxide scale, and hence some experiments were carried out to examine the tracer diffusion of sulfur through Cr203 at 1000° C in the upper temperature range experienced by jet engine blades and vanes. Some hot-pressed Cr203 discs of quite high density were available from an earlier investigation1 on the rate of crf3 migration through Cr203. The Cr203 was 99.3 pct pure and contained -0.06 pct Fe as the largest metallic impurity. Additional data is given in Ref. 1. In this earlier work it was found that the rate of cation diffusion was independent of the atmosphere of thermal equilibration when using nitrogen, argon, or air, and also that the electrical conductivity of the hot-pressed Cr203 compacts was likewise independent of atmosphere in this range, thus indicating that the de-

Jan 1, 1969

LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION Transactions Number Place Date Vol Page 1 Wilkes-Barre, Pa May, ?71 1 3 2 Bethlehem, Pa August, ?71 1 10 3 Troy, N Y November, ?71 1 13 4 Philadelphia, Pa February, ?72 1 17 5 New York, N Y May, ?72 1 20 6 Pittsburg, Pa October, ?72 1 25 7 Boston, Mass February, ?73 1 28 8 Philadelphia, Pa May, ?73 2 3 9 Easton, Pa October, ?73 2 7 10 New York, N Y February, ?74 211 11 St Louis, Mo May, ?74 3 3 12 Hazleton, Pa October, ?74 3 8 13 New Haven, Conn February, ?75 3 15 14 Dover, N J May, ?75 4 3 15 Cleveland, 0 October, ?75 4 9 16 Washington, D C February, ?76 4 18 17 Philadelphia, Pat June, ?76, 5 3 18 Philadelphia, Pa October, ?76 5 9 19 New York, N Y February, ?77 5 27 20 Wilkes-Barre, Pa May, ?77 6 3 21 Amenia, N Y October, ?77 6 10 22 Philadelphia, Pa. May, ?78 6 18 23 Chattanooga, Tenn May ?78 7 3

Jan 1, 1923

By Robert Maddin, Neng-Kuan Chen

THE (001) planes have been reported as the cleavage planes in body-centered cubic metals such as alpha-iron and tungsten.' However, in molybdenum, which is also body-centered cubic, experimental X-ray evidence indicating a similar cleavage plane still seems lacking. Tsien and Chow" observed microscopically in the extension at around 1000°C of molybdenum single crystalline wires 0.25 mm in diam that the fracture plane seemed to be parallel to the operative slip plane, which appeared to be (110) at that temperature. Zapffe' pointed out from fractographic study of polycrystalline molybdenum that "although the transgranular pattern is characteristically non-crystallographic, patterns occasionally reveal {100} cleavage." This has been generally assumed to be the case at ordinary temperatures. In the present experiments, a single crystal of Fansteel molybdenum, Vs in. diam x 2 in. long, prepared by the methods described by Chen, Maddin, and Pond" was fractured at room temperature by bending. The fracture surface appeared to be quite similar to the cleavage surface of zinc and was crys-tallographic. A back-reflection Laue photogram was made using 35 kv copper white radiation; the X-ray

Jan 1, 1952

By Brandon H. Grove

The Zistersdorf field, near Vienna, continues to be Austria's only producing area. During the year the field was slightly extended by Rohol Gewinnungs A.G. in its Rag 2, which in April came in for an initial 120 tons daily through an 8-mm. (0.315-in.) bean, from the twelfth Sarmat sand at 1447 m. (4747 ft.). The amount of fluid produced by this well has remained essentially constant, but after the first several months water appeared and increased to some 50 per cent of the total. TWO subsequent extension wells, Rag 3 and Rag 5, northeast and west of Rag 2, found only water-bearing sands, and drilled through the main fault and into the Flysch at 1683 and 1401 m. (5522 and 4596 ft.), respectively. At the close of the year preparations were under way to deviate both wells away from the fault to test still deeper sands. Within the previously proven area of the field Erdolproduction's Gosting VII came in flowing a maximum of 440 tons daily, the highest individual production yet recorded. This company's Gosting VIII also yielded an initial production of 20 tons daily, and its Gosting XI, drilling

Jan 1, 1938

By Allan B. Tanner

The effects of radon in drillholes on gamma-ray logs have been described by L. S. Hilpert and C. M. Bunker1 Since these effects may cause drastic error in the evaluation of uranium deposits, it is useful to know the conditions under which significant amounts of radon tend to accumulate in drill- holes. In the studies described here, atmospheric conditions were found to dominate in the control of the behavior of radon in drillholes in the vicinity of a uranium orebody. The site of the investigation was in McKinley County, New Mexico, about 12 miles north of Grants. Drillholes of 4 ¼ -in. diam, on 25-ft and 100- ft centers, penetrate ore in dry rock at a depth of about 100 ft. A geologic log of the drillhole of primary interest is shown in Fig. 1. Gamma-ray logs revealed three zones of ore-grade mineralization in the Todilto limestone. A 6-ft zone, the lowest of the three, assayed 0.20 pct U3O8 by chemical analysis. The limestone ores in this area contain disseminated uraninite and some yellow and orange secondary minerals.

Jan 7, 1959

The suggestions of the members of the Institute are very much desired by the Committee on Nominations prior to deciding upon its nominations to fill the places of those officers who retire early in 1917. The Committee must make its final report to the Board of Directors early in October. The members are, therefore, asked to send in promptly their suggestions for Directors as well as for Vice-Presidents and President. The Committee hopes to hear from a large number of the members. The officers to be elected at the annual meeting in February, 1917, are: One officer, known as Director and President. Two officers, known as Director and Vice-President. Five officers, known as Director. The attention of members is called to Articles V and VII of the Constitution, and to By-Law XIII, which reads as follows: "The geographical districts to be considered by the Committee on Nominations shall be as follows, until otherwise ordered by the Board. District No. 1. New England, New York, and New Jersey, excepting New York City and district, which is provided for in the Constitution. (N. B.-New York City and district is designated District 0.) District No. 2: Pennsylvania.

Jan 6, 1916

By K. N. Han, H. Lee, M. C. Fuerstenau

An investigation of the recovery of finely-divided cassiterite and silica particles less than 1 µm (1200 mesh) in size has been carried out using packed and fluidized beds. The bed particles used included cassiterite and silica particles ranging from 44 to 210 µm (325 to 70 mesh). Effects of various system parameters on the recovery and selectivity of cassiterite fines were investigated. System parameters included pH of the slurry solution, superficial velocity, slurry concentration, and bed particle sizes. High recoveries of cassiterite fines were obtained at pH 4.0 and slow slurry flow rates. In a packed bed system, recovery of cassiterite fines was greater than 95%, while that of silica fines under the same conditions was about 35%. Although the total recovery per pass is not as good as the packed bed, the fluidized bed system exhibits good recovery in general and an excellent selectivity of cassiterite fines. There is an optimum superficial velocity, vo, for the rate of fine particle uptake and the apparent rate constant has the form of Kvo1/2- K'vo, where K and K' are system constants.

Jan 1, 1985

By Edwin H. McKee

Eruption of rhyolitic ash-flow tuffs in the area of the McDermitt (Cordero) caldera began about 17.4 million yr (m.y.) ago and continued for about 1.5 m.y. During this period of silicic eruptions, a circular area about 30 km in diameter collapsed to form a caldera that subsequently filled with sedimentary and volcanic rocks. A total of more than 200 km30f silicic rocks was erupted from the volcano. The final phase of igneous activity, about 15.0 m.y. ago, included resurgent doming and intrusion in the south-central part of the caldera. Three to 4 m.y. later (-1 2 m.y. ago), hydrothermal solutions using the northern part of the caldera ring fractures as conduits deposited silica, cinnabar, pyrite, alunite, and other minerals in tuffaceous lake beds and volcanic rocks accumulated within the caldera. The ore-forming solutions may have been a residuum from the silicic magma, or connate water, or ground water heated by the still-hot resurgent magma in the central part of the caldera. The source of the mercury and other elements has not been identified.

Jan 1, 1977

By Olav Idelgeland

FROM indirect evidence point defects have been believed to influence the fatigue behavior of metals and alloys.1,2 Measurements of changes in resistivity made after cyclicstressing at low temperatures indicate that a very high density of defects is present, part of which may be removed by room-temperature annealing.3'4 These results are consistent with the generation of a high number of point defects at low temperatures. Corresponding measurements made after room-temperature stressing did not show any recovery effects.3 This was attributed to a stabilization of the dislocation network after a few thousand cycles without generation of vacancies. In this laboratory resistance measurements of copper single crystals, shaped as normal fatigue specimens ,5 have been made with a Kelvin double bridge at room temperature during and after cyclic stressing at 80 cps by comparing with a dummy at a close and constant temperature. Temperature differences were measured to ±0.025°C with fine thermocouples taped onto the gage lengths. Potential leads were tin-soldered into small holes in the gage length to give stable values. Corrections for differences in temperature and changes in mean length of the specimen were made according to the formula:

Jan 1, 1968

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who called at Institute headquarters during the period June 10, 1916 to July 10, 1916: Arthur Adams, Miami, Ariz. John M. Lovejoy, New Rochelle, N. Y. J. H. Batcheller, Mattapoisitt, Mass. J. F. Manning, Seoul, Korea. R. S. Bonsib, Low Moor, Va. E. P. Mathewson, Anaconda, Mont. E. L. Booth, New York, N. Y. Edwin W. Mills, Seoul, Korea. C. L. Bryden, Scranton, Pa. Arthur Notman, Bisbee, Ariz. F. Crabtree, Pittsburgh, Pa. L. B. Reifsneider, Daiquiri, Cuba. L. B. Eames, Pueblo, Colo. W. S. Schuyler, Berkeley, Cal. S. J. Gormly, Guayacan, Chile. 0. N. Scott, Toronto, Ont., Canada. Ernest A. Hersam, Berkeley, Cal. Arthur F. Taggart, New Haven, Conn. A. W. Hudson, Douglas, Aria. Warren D. Thompson, Boston, Mass. Chas. W. Johnston, West Norfolk, Va. Thor. Warner, IGngman, Ariz. Rodolphe L. Agassiz has been chosen president of the Calumet & Hecla Mining Co., an office which has been vacant for over a year. Percy E. Barbour, Managing Editor of the Engineering and Mining Journal, resigned his commission as 2d Lieutenant in the Main Coast.

Jan 8, 1916

By Ossi E. Palasvirta

The authors are to be congratulated for their interesting article, which thoroughly illustrates the variables inherent in filtration of taconite concentrate. The work and the conclusions based thereon largely parallel the test work done by the writer at the Pilotac plant* and the experience gained with a commercial size agitating disk filter in the same plant. At Pilotac, however, a thorough study was also made of the effect of depolarizing (demagnetizing) the filter feed, and it is the purpose of this discussion to comment on the merits of depolarization of the magnetite concentrate prior to filtering. The work at Pilotac was done in three phases: 1) preliminary laboratory testing with a circular filter leaf of 0.047 sq ft, followed by 2) plant testing using a 4-ft diam, single-disk agitating filter that was purchased on the basis of the pilot tests on the 4-ft model. In the laboratory tests depolarization was achieved by slowly withdrawin4 batches of thickened concentrate from a coil producing an alternating field of about 300 oersteds. In plant tests the standard Pilotac procedure1 was employed, wherein the pulp falls freely through the depolarizing coil.

Jan 5, 1958

The following is a partial list of members and guests who called at Institute headquarters during the period July 10, 1917, to Aug. 10, 1917: G. A. Collins, Seattle, Wash. Norman Picot, Melbourne, Aust. A. D. R. Galloway, Komfrodua, W. Africa. W. E. Pomeroy, El Paso, Tex. F. Lynwood Garrison, Philadelphia,; Pa. Francis R. Pyne, Elizabeth, N. J. Geo. M. Henderson, Bland, N. M. W. L. Remick, W. Norfolk, Va. L. B. Herr, Jr., So, Bethlehem, Pa. M. F. Sayre, Schenectady, N. Y. Zay Jeffries, Cleveland, 0. Leighton Stewart, New York, N. Y. H. H. Lauer, Allentown, Pa. Randolph D. Talmage, Joplin, Mo. Wm. B. McKinlay, Yonkers, N. Y. H. J. Volker, Ossining, N. Y. A. N. Mackay, Republic of Colombia. Dwight E. Woodbridge, Duluth, Minn. Edmund Newton, Minneapolis, Minn. Kwong Wu, Peking, China. J. N. Acosta has resigned his position as mining engineer for the Shannon Copper Co., Gleeson, Ariz., and is now engaged as consulting engineer for Lower California, Mexico, with headquarters at San Diego, Cal. L. D. Albin, formerly assistant general sales manager of the Ingersoll-Rand Co., was appointed general sales manager on July 25,1917.

Jan 9, 1917

LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION Transactions Number Place Date Vol Page 1 Wilkes-Barre, Pa May, ?71 1 3 2 Bethlehem, Pa August, ?71 1 10 3 Troy, N Y November, ?71 1 13 4 Philadelphia, Pa February, ?72 1 17 5 New York, N Y May, ?72 1 20 6 Pittsburg, Pa October, ?72 1 25 7 Boston, Mass February, ?73 1 28 8 Philadelphia, Pa May, ?73 2 3 9 Easton, Pa October, ?73 2 7 10 New York, N Y February, ?74 211 11 St Louis, Mo May, ?74 3 3 12 Hazleton, Pa October, ?74 3 8 13 New Haven, Conn February, ?75 3 15 14 Dover, N J May, ?75 4 3 15 Cleveland, 0 October, ?75 4 9 16 Washington, D C February, ?76 4 18 17 Philadelphia, Pat June, ?76, 5 3 18 Philadelphia, Pa October, ?76 5 9 19 New York, N Y February, ?77 5 27 20 Wilkes-Barre, Pa May, ?77 6 3 21 Amenia, N Y October, ?77 6 10 22 Philadelphia, Pa. May, ?78 6 18

Jan 1, 1923

H. 0. Hofman, Boston, Mass. (communication to the Secretary*) :—The experimental demonstration by Professor H. Ries, of the fact that a mixture of clay and finely-ground flux will melt more readily than one in which the flux is less fine and therefore less intimately mixed, is very striking, and will be appreciated especially by those who have to discuss, before classes of students, fusions on a small or a large scale. The statement, that I " rather disputed" the influence of size of flux-particles on the ease with which fire-clay mixtures fused, is an erroneous inference from the paper written by Mr. B. Stoughton and myself in 1898.' We did not undertake to study the influence upon fusibility of the sizes of the particles, either of clay or flux. What we did try to find out was, whether the common practice of finely grinding raw or burnt clay, or a mixture of the two, before testing with Seger cones for resistance to heat and to fluxes, xould give the same results as if the materials were tested just as they were going to be

Jan 1, 1904