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President MRS. ROBERT HURSH River Road, Silvermine Norwalk, Conn. First Vice -President MRS. WILLIAM C. SCHNEIDER 45 Wayne Ave. White Plains, N. Y. Second Vice-President MRS. ERNEST H. WOLFES 180 Riverside Drive New York, N. Y. Third Vice-President MRS. JOHN C. BURTON 271 Fox Meadow Road Scarsdale, N. Y. Fourth Vice-President MRS. S. A. IONIDES 379 Marion Street Denver, Colo.

Jan 1, 1941

[Note.—The paper of Mr. W. H. Hoffman (Glen Summit, October, 1891; Trans. xx., 602), on "Practical Results in the Magnetic Concentration of Iron-ore," together with a paper by the same author (Baltimore, February, 1892; Trans. xxi., 126), on "Granulating Magnetic Iron-Ores with thesturtevant Mill atCroton Magnetic Iron-Mines, N. Y.," and also the papers Presented at this meeting,

Jan 1, 1893

By M. B. Bever, A. K. Jena

Equations for the heat effects of additions of mixtures of multicomponent phases to a solution have been derived in terms of the enthalpy interaction coefficients. By these equations and the measured composition dependence of the heat effects on addition of mixtures of Ag-Cd solid solutions and elemental gold to liquid tin-rich solutions, values of the enthalpy in-teraction coefficients in tin-rich solutions at 541°K have been obtained. Analysis of these results in terms of the regular solution theory and the quasichemical theory suggests that near the melting point of the solvent association in the solution becomes important. SEVERAL recent papers have discussed the nature of dilute solutions on the basis of measured enthalpy interaction coefficients. l-3 These coefficients contribute to the understanding of the constitution of solutions and can be used for the evaluation of thermo-dynamic data of multicomponent systems. Their experimental determination, however, is laborious. This communication reports values of the enthalpy interaction coefficients of silver, cadmium, and gold in liquid tin-rich solutions obtained from the measured heat effects of additions of mixtures of Ag-Cd solid solutions and elemental gold to liquid tin-rich solutions. These measurements were made in the course of the determination of the heats of formation of Ag-Cd solid solutions reported in a concurrent publication.4 THE HEAT EFFECT OF AN ADDITION TO A SOLVENT This analysis is concerned with the addition of a mixture of multicomponent phases from the temperature To to a solvent of known composition at temperature T. If Nmixture << Nsolvent, where N designates the gram-atoms involved, the heat effect per g-atom of mixture added can be expressed as (HT - HT )i = difference in heat contents of component element i in the mixture at T and To Q = heat effect on solution of the mixture at temperature T Also1 Q = S Xi [2] where ?Hi ,T,x = relative partial enthalpy per g-atom of i in solution at temperature T and composition of the solution x x = average of the atom fractions of the added material in solution before and after the addition The relative partial enthalpy ?Hi per g-atom of an element i in a dilute solution composed of a solvent 1 and the solutes j = 2, ... m is related to the interaction coefficients by the following equation5 ?Hi - ?Hi-?Hi,x1-1 + S n1ixj+ . . . +S...S...S nrixn2... Xnji...Xnmm+... [3] vhere Xj = atom fraction of solute j in the solution nri = the rth order enthalpy interaction coefficients, which can also be represented by the more general designation5 L(i)n2,n3...nm and nj may have any positive integral value or zero. For identification of various rth order interaction coefficients, nri is written as nn2i2,...nij,...nmm. Eqs. [1], [2], and [3] combine to give the following general equation for the heat effect on addition of a small quantity of a mixture to a large quantity of a dilute solution n = _?ga ?Ha,To + ? Xi(HT - HT o)i a. i + ?xi?Hi,X,i?1 + ??xnjixj + . . . + ???. . .?. . .?xinrix2n2. . . xnji. . . xnmm+ . . . [4] The first term on the right-hand side of this equation is the heat of decomposition at the addition temperature of the phases present in the mixture, the second term is the heat required to raise the temperature of

Jan 1, 1970

By Will Mitchell, T. G. Kirkland, C. L. Sollenberger

The beneficiation of a scheelite ore by flotation was investigated with emphasis on determining optimum conditions for obtaining maximum grade and recovery in the rougher concentrates. Variables such as pH, time, temperature, and pulp density during conditioning were plotted against the grade and recovery of the rougher concentrates. Several gangue regulators were tried, and several methods of cleaning rougher concentrates are described.

Jan 1, 1951

By M. Bevis, A. G. Crocker

A. G. Crocker and M. Bevis (Battersea College of Technology)— Richman and Richman and conard17 have recently published the very interesting results of their studies on the plastic deformation of Fe-Ni-C martensites and of an Fe-5 wt pct Be alloy. Other work on the range of Fe-Be alloys containing between 16 and 27 at. pct Be has also been reported by Richman." One of the fascinating features of this work is that the materials investigated deform primarily by means of twinning and that several twinning modes are operative in addition to the well-established (112 ) mode of bcc materials The composition planes of these unusual twins were determined using a single-surface analysis and reported as (0131, "{045)" or "{089)", and "{2,3,10)" or "(127)". (It is now thought1&apos; that the "{0,1,13)" habit reported for the Fe-Ni-C alloys&apos;&apos; is more likely to be near "{127)". Although the full twinning elements of these unusual twinning modes could not be determined directly from the experimental results, the authors attempt to deduce the elements by considering twin intersectionslQ and by using the projection technique of Jaswon and Dove.&apos; The basic assumption of their approach is that the (013) habits are truly rational planes but that the other habits are irrational and merely approximated to by the indices quoted above. They thus deduce that the twinning mode describing the (013) habit is either Type I or compound and that the modes describing the other habits are Type 11. This deduction must however be false as all twinning modes in cubic structures obeying the classical orientation relationships of deformation twinning must be compound. Type-I and Type-I1 modes can occur in all of the other crystal systems (indeed in the triclinic system compound modes are not allowed), but in the cubic system only compound modes can arise. This fact, which does not appear to be well-known, fol- lows immediately from the relations between the four twinning elements defining a twinning mode. Thus for a Type-I mode which is uniquely defined by the rational twinning elements K1 = hi and tj2 = vi (i = 1, 2, 3), the Kz qd 771 elements are given by: where the summation convention of the tensor calculus has been adopted. For cubic materials the metrics cij Iand cij reduce to the unit tensors 6ij and 6ij so that we have It is clear from these equations that both ki and ui must take on integral values; i.e., Kz, and ql must be rational, if hi and vi are integers, i.e., if K1 and 77~ are rational. Thus for cubic materials a Type-I mode must degenerate into a compound mode and the same result also arises for Type-II modes. The apparently irrational habits observed by the authors can thus not be explained in terms of Type-I1 twinning if the classical laws of deformation twinning are to be obeyed. An alternative explanation of the irrational habits is that they may arise from twinning modes with four irrational twinning elements. These modes, which do not obey the classical orientation relationships associated with deformation twinning, have been shown to arise as the result of double twinning processes in magnesium,22 but may also describe a simple shear on an irrational plane in an irrational direction. Indeed double twinning processes in bcc

Jan 1, 1963

By William E. Ford, Edward Salisbury Dana

The aluminate, ferrates, etc., allied chemically to the borates, have been already intro- duced among the oxides. They include the species of the Spinel Group, pp. 418-423, also Chrysoberyl, p. 423, etc. SUSSEXITE. In fibrous seams or veins. H. = 3. G. = 3.42. Luster silky to pearly. Color white with a tinge of pink or yellow. Translucent. Index, 1.59.

Jan 1, 1922

By H. Margolin, E. Ence

Two versions of the Ti-Mn binary diagram have been published recently.&apos; , -0th diagrams show two compounds in the region between 40 and 70 wt pct Mn, but disagree as to the reaction in which these compounds are involved. The investigation of the manganese-rich portion of the Ti-Mn binary diagram was undertaken at New York University as part of an investigation of ternary systems with titanium and manganese in order to determine which of the proposed diagrams is correct. A number of alloys between 31 and 70 pct Mn were prepared in a manner similar to that described by Cadoff and Nielsen; except that low currents (110 amp in argon atmosphere) and long melting times (up to 20 min) were used to prepare the alloys. Compositions were determined from weight-loss data, assuming all loss as due to manganese. Heat treatments were carried out with relatively large pieces, since there was a tendency for manganese to be lost during heat treatment. When X-ray diffraction data was to be obtained, the central parts of heat-treated specimens were used to make filings or powders which were not heat treated. Specimens were heat treated from the as-cast state. Heat-treatment times were as follows: 1150°C, 1 day; ll00°C, 2 days; 1000°C, 5 days; and 900°C, 15 days. It should be noted that equilibrium was not attained at 900°, 1000°, and in one case, at 1150°C. Metallographic specimens were electrolytically polished and strain etched by a technique described elsewhere.&apos; At least four, and possibly six, phases were found in the region investigated. On the basis of information available at this time, a completely self-consistent diagram cannot be constructed, and therefore data are presented only for those phases which have been identified by both X-ray and microstruc-ture. Of the compounds detected, the one highest in manganese is the Laves phase, TiMn,, which is hexagonal with a MgZn, type of structure.V he diffraction data for TiMn2 from a 70 pct Mn alloy annealed at 1150°C are shown in Table I. The c/a ratio and parameters of TiMn2 agree well with those of Wall-baum hnd Rostoker et al. The values obtained here are c/a = 1.641, a = 4.825A. Another compound is the y-phase which is estimated to contain about 60 pct Mn. The y-phase has a structure which is identical to that of TiMn, with c/a = 1.639, a = 4.906Å. The fact that y has a Laves-type lattice would suggest that TiMn, has a range of solubility which extends from the composition of TiMn2 (69.6 Mn) to that of y (60 pct Mn). However, this could not account for microstructures which, in the 60 to 70 pct Mn region, show several phases in both the as-cast state and after annealing at 1150°C. Fig. 1 shows a two-phase structure of a 60 pct Mn alloy annealed at 1150°C. The phases present are y (white) and e (dark). If y were TiMn, then, according to Rostoker et al.,&apos; the second phase of Fig. 1 should be P-Ti. The diffraction data for the 60 pct Mn alloy of Fig. 1 are shown in Table I. The starred d-values are from the e-phase and these lines do not correspond to those of &Ti. Comparison of as-cast and 1150°C microstructures of the 60 pct Mn alloy indicates that e precipitated from y. Since y has a

Jan 1, 1955

By Stanley W. Ivosevic

The South-Central Osa Peninsula produced around 30,000 kg (100,000 troy oz) of gold since prehistoric times. Gold freed by erosion from quartz lodes in the Mesozoic Nicoya ophiolite complex was reconcentrated through three generations of Quaternary sedimentary deposits. Resultant gold placers grade upward from 1 g/m3 (0.03 troy oz/m3) and are of moderate size.

Jan 1, 1980

F. W. Matthiessen, who, with E. C. Hegeler, of La Salle, was one of the creators of the zinc industry in the-United States, was born in Altona, Schleswig-Holstein, Germany, Mar. 5, 1835. He was one of a family of remarkable brothers, two of whom were long absociated in this country with the sugar and glucose industry. Mr. Matthiessen was educated at Freiberg, and came to this country in 1857 with Mr. E. C. Hegeler, after having, in company with that gentleman, visited the mining districts of Germany, Belgium, and England. They first went to Friedensville, near Bethlehem, Lehigh County, Penn., wherc attempts had already been made to produce zinc from the ore deposits found in that place. The ore was a he silicate but all attempts to extract zinc from it had failed. Mr. Matthiessen and Mr. Hegclcr were successful, but declined to invest their money in the zinc industry at Bethlehem because 01 certain local conditions. Hearing of the discovery of zinc -ore in the West, they visited both Wisconsin and Missouri and thought of settling in the coal region of East St. Louis. Finally La Salle, as being near to the Wisconsin fields and having much coal, was selected ae the site of the new smelting company, and on Dec. 24, 1858, the first shovelful of dirt was turned for the buildings of the new industry. The Civil War at first interfered with the manufacture of zinc, but afterward a lively demand for the metal arose and the future success of the institution was established. A large rolling mill was added in 1866, and in 1881 the manufacture of sulfuric acid as a byproduct was begun. Mr. Matthiessen also developed the Western Clock hlanufacturing Co. of La Salle, which manufactures the Big Ben alarm clock, from a small plant having 25 men to the present large institution which employs some 2000 workers. Mr. Matthiessen&apos;s affiliations with other metal industriefi have been numerous. But the contributions of the great zinc manufacturer to the causes of philanthropy and education have made his name known throughout the country, beyond industrial circles. He has given to the city of La Salle probably a sum total of $500,000 in various benefactions. Among the objects of his philanthropy were the La Salle-Peru Township High School, which he has made a model institution of secondary education for the entire United States; also the Tri-City Hygienic Institute of La Salle, Peru, and Oglesby, Ill., which he endowed for $200,000 This Hygienic Institute, which is unique in the United States, has a traincd staff of health officers, bacteriological laboratory, medical library, infant welfare station, milk station, free dental clinic, school nurse, and isolation hospital. Mr. Matthiessen was elected mayor of the City of La Salle three times and gave generously to the municipality of which he was the head. He also saved for the people of Illinois one of the great scenic districts of the state, Deer Park, with its cafions and natural beauties, which he con-verted into a model scenic resort, and the proceeds of which he gave to the charities of the Tri-Cities in which he lived. He died on Feb. 11, 1918.

Jan 1, 1920

By H. M. Howe

On commencing the construction of the Orford Company&apos;s copper smelting works, at Bergen Point, N. J., I endeavored to convince our President, Mr. W. E. C. Eustis, by actual tests, that at the pressure of from 15 to 18 ounces per square inch, employed by us in smelting, less power was consumed in delivering a unit of blast by a Baker blower than by a fan blower. I attempted to prove this in the following manner: Across the mouth of a No. 5) Baker blower I firmly fastened a board with two round holes, 6 inches in diameter, cut in it. The board was fastened so tightly that no air could escape except through the holes. I then drove the blower at several differerent speeds, observing the pressure at which the air excaped through the two openings for each different speed of the blower, and also indicating the engine, whose only work at that time was to drive the blower. From this I calculated the quantity of power required to deliver, with a Baker blower, sufficient air to keep the pressure at a given point, while it escaped freely through the two six-inch apertures into the open air; or, in other words, to deliver air at a given pressure through these two openings. From the total power so consumed it was, of course, necessary to deduct the power which was required to drive the engine itself. This was ascertained by removing from the engine the belt which drove the blower, and then noting the quantity of power consumed in simply turning the engine over without any

Jan 1, 1882

By Thomas S. Blair

I FEEL a certain sense of responsibility in bringing before you the subject of the direct process in iron manufacture. I am aware that, in such a body as I have now the honor of addressing, there are few who are not already so well informed upon its past history that it would be a weariness to them to listen to anything else than an account of practical success. Yet, to claim that success involves so much that, if I do not make good my claim, I deservedly expose myself to severe criticism. The whole literature of the art, so far as it relates to the direct process, is, up to this time, but a history of failure. It is safe to say that more money, time, and talent have been fruitlessly spent in the pursuit of this object than in all the other unsuccessful efforts in the whole line of iron metallurgy. A distinguished authority in patent law has remarked that " the invention records of the United States and of foreign countries are filled with the waifs and abandoned relics of these abortive struggles." Dr. Percy, whose great work may be taken as an epitome of all that was worth mention, whether useful or curious, in pig-iron metallurgy, up to the date of its publication (1864), after giving elaborate accounts of various attempts at the direct process, condenses his own opinion of all that had been then effected, into a brief but summary comment upon a pamphlet of one of the sanguine inventors who had said: "It is evident that the present mode of working iron

Jan 1, 1874

BRANCH COUNCILS Mining Branch E R Price, Chairman (Coal) Howard A Meyerhoff (Industrial Minerals) J V Beall, Secretary Richard M Foose (Industrial Minerals) Carroll F Hardy (Coal) Frank A Hardlaw (Mining, Geology, and Geophysics) S J Swainson (Minerals Beneficiation) Philip J Shenon (Mining, Geology, and Geophysics) Grover J Holt (Minerals Beneficiation) A C Callen (Mineral Industry Education) C H. Behre, Jr. (Mineral Economics)

Jan 1, 1952

By Waldemar Lindgren

The important investigations of Dr. G. F. Becker at Steamboat Springs, Nev., in 1885, aided by the analytical work of W. H. Melville, established the fact that sulphides were being deposited at the surface by hot ascending waters.&apos; Steamboat Springs is situated near the eastern base of the escarpment of the Sierra Nevada, six miles distant from the Comstock lode.

Jan 1, 1906

By C. F. Smart

The heat treatment of the bronze composed of 88 per cent. copper, 10 per cent. tin, and 2 per cent. zinc, has been investigated by H. S. and J. G. S. Primrose,&apos; and also by the U. S. Bureau of Standards.2 The results obtained by H. S. and J. G. S. Primrose on dry-sand castings subjected to reheating followed by air cooling, or by quenching in water, are shown in Figs. 1 and 2. The values for tensile strength have been converted from tons per square inch to pounds per square inch. Figs. 3 and 4, have been plotted from values obtained by the Bureau of Standards on material of the same composition and treatment. Both investigations show that the ductility of the cast bronze is improved by heating to 700&apos; C. and cooling in air, the strength not being impaired by this treatment. They are not in agreement, howevcr, as to the effect of quenching, Messrs. Primrose reporting a decrease, and the Bureau of Standards an increase, in both strength and ductility when the cast bronze is heated to 600&apos; or 700&apos; C. and quenched. The present investigation was undertaken to study the effect of annealing followed by different rates of cooling, and, in particular, the

Jan 1, 1921

By M. E. Wadsworth, P. H. Yu, C. K. Hansen

A study of the rate of dissc5lution of chalcopyrite (CuFeS2) in acidic solutions under oxygen overpressures was carried out by measuring the rate of formation of cupric ions in solution. Effects of temperature, oxygen partial pressure, surface area, and concentration of sulfuric acid were evaluated. A sized batch of chalcopyrite was leached in the temperature range of 125° to 175°C and in the pressure range of 75 to 400 psi of oxygen. In 0.5 N H2SO4 all products of reaction went into solution except for trace amounts of elemental sulfur. The dissolution of chalcopyrite followed linear kinetics and was essentially independent of hydrogen ion concentration for H2S04 concentrations between 0.2 and 0.5 N. The oxygen dependence indicated adsorption approaching limiting values with increasing oxygen pressure. The linear mechanism was explained in terms of steady-state adsorption of oxygen at the chalcopyrite surface followed by a surface reaction. The enthalpy of activation for adsorption of oxygen was found to be approximately 33 kcal per mole. An activation enthalpy of approximately 9 kcal per mole was observed for the surface reaction. Charge transfer reactions are not rate controlling in the process.

Jan 1, 1973

By W. W. Harvey, F. O. Dudas

Toward hot hydrochloric acid, the usual order of reactivities of the common copper sulfide and associated minerals is reversed, and the rates of H2S formation vary as [ ]. The iron component of chalcopyrite and bornite reports to the solution as ferrous chloride, while pyrite remains essentially unreacted. If a pressure of H2S is maintained in the reactor, copper solubilization is suppressed, and the primary copper sulfides are converted to finely divided secondary sulfides (principally covellite). The HCl leach reside then consists mainly of covellite, pyrite and acid-insoluble gangue. Copper can be selectively leached from this upgraded concentrate to yield a clean, strong copper sulfate solution for direct electrowinning. Preliminary analysis indicates competitive economics with respect to established hydrometallurgical processes. Other concentrate treatments based on an initial HC1 leach are proposed and relative advantages compared. The common denominator of the major process routes considered is the requirement to regenerate HC1 from an FeC12 solution. Five distinct concentrate compositions were employed in the experimental study, which included some attention to the fates of selected minor constituents of the copper concentrate, especially gold, silver, molybdenum, arsenic and selenium. Significant mineralogical features of reactants and products are described.

Jan 1, 1978

By Clement K. Chase

The ammonia leach for copper recovery is discussed from historical and current practice standpoints. The chemistry of the system is presented together with Eh-pH and copper-ammonia solubility curves. A list of metals forming ammine complexes is presented. The advantages and disadvantages of the ammonia leach as applied to copper recovery in conjuction with modern liquid ion exchange techniques are compared.

Jan 1, 1980

Geological Survey of the State of Maine, Orono, Me. Joseph Conrad Twinem, State Geologist In the years 1837, 1838, 1839, Charles T. Jackson made three reports on the geology of Maine Reports were made in 1861-1862 by C. H Hitchcock entitled, respectively, "General Report on the Geology of Maine" and "Geology of Maine." These old reports are now out of print

Jan 1, 1933

By AIME AIME

THE Western States Joint Convention opened at Denver on Sept. 20, with about 400 registered the first day. Monday was devoted to the American Mining Congress, and the afternoon session was taken up with a discussion of the public land laws of the United States. Hubert Work, Secretary of Interior, and William Spry, Commissioner of the General Land Office, presented a comprehensive review of the origin and operation of the laws and argued against any general change in the system. Charles E. Winter, Congressman from Wyoming, marshalled the arguments in favor of turning over the public lands to the states within which they lie, and George H. Dern, Governor of Utah, presented a well-reasoned argument in favor of allowing the school sections to pass to the states regardless of their mineral or non-mineral character. The debate made it clear that in the West especially, there is strong feeling against any further development of the policy of reserving and leasing the public lands. Tuesday forenoon was devoted to the Silver Producers Association, F. H. Brownell and Charles A. Thomas being the principal speakers, and in the after- noon the American Association of Petroleum Geologists met with Alex. W. McCoy presiding, and Glenn C. Clark, J. V. Howell, and J. W. Beede presenting papers.

Jan 1, 1926

By N. R. Tipman, G. E. Agar, L. Paré

The flotation chemistry of the commercial INCO matte separation process was investigated. The slow cooling of Bessemer converter matte forms discrete phases of Cu2S and Ni3S2 and a Cu-Ni alloy. After magnetically removing the alloy, the Cu2S and Ni3S2 are separated by flotation at pH 12.4 (saturated lime) using diphenyl guanidine (DPG) as both collector and frother. DPG has been used exclusively in this flotation process because of its unusual selectivity for copper minerals. The surface product resulting from chemisorption of DPG onto theCu2S was identified as the double salt CU(DPG)2SO4.CU(DPG)2(OH)2. The adsorption followed Langmuir behaviour up to a monolayer coverage. In the absence of DPG, the rapid adsorption of oxygen by Cu2S in flotation pulps was observed. The surface product was identified as the insoluble basic copper sulfate CuS04.3Cu(0H)2 with the production of sulfate ion. In the presence of DPG, the oxidation reaction appears to be suppressed. The frothing properties of DPG and commercial frothers were compared. DPG is not a powerful frother. Batch flotation tests confirmed that DPG is a highly selective collector when compared to most sulfhydryl collectors.

Jan 1, 1976