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By R. Roberge, H. Herman

Jan 1, 1969

By Charles Rich, Robert Munson, Leonard Obert

Improved methods of predicting the caving characteristics of ore bodies is discussed. Experiments were conducted at Climax mine, Climax, Colo., on varied rock compositions. The cavability of adjacent areas, as well as seismic energy absorption proved to be good factors in determining cavability. Seismic velocity, core recovery, and rock quality designation (RQD) were found to be not as reliable.

Jan 1, 1977

INTRODUCTION TO STATISTICS It is necessary now to digress from the direct study of appraisal techniques to consider an important tool for the mineral appraiser. Whenever a great deal of data have been accumulated, such as might be gained through the sampling process discussed in the preceding chapter, the application of statistical methods should be considered. Statistical methods are used for descriptive purposes and for the organization and summarization of quantitative or numerical data. Descriptive statistics covers the tabulation of data, its presentation in graphical or pictorial form, and the calculation of its several descriptive measures. It is not the intent of the brief summary of statistics that will be outlined hereafter to cover the total breadth and scope of mathematical statistics. It is the intent of this and the following chapters to review a few of the statistical concepts that have the most direct bearing upon the problems involved in mineral evaluation. Should the reader desire to go more fully into statistical theory and mathematics, numerous texts and publications are available.

Jan 1, 1980

By Oliver B. Hopkins

During 1931 Peru maintained its position as the ninth oil-producing country of the world, with an output somewhat greater than that of Trinidad and Argentina, and considerably less than for Colombia and Mexico. Outside of the three old producing fields, there was little or no activity of importance; no new areas were brought in and no extensive wildcat drilling was done. On the other hand, the old fields continued to produce at a rate only slightly below normal and such restriction as existed may be attributed to market and not to field conditions. Political disturbances during the spring led to several strikes in the field, causing temporary suspension of activities there. However, such troubles were of short duration and no permanent loss of production was sustained. The production in barrels during the past three years for the three coastal fields of Peru has been as follows: The oil industry in Peru is relatively old; 29 wells were drilled in the Negritos area between 1888 and 1898. Prior to 1900 the production was relatively insignificant but from 1900 until 1929, it has slowly but steadily increased to a maximum annual production of over 13,000,000 bbl. The potential production of the fields since 1939 has exceeded the production of those years; the actual production has been controlled by market conditions. The production of the property of the International Petroleum CO. since 1900 has been just over 100,000,000 bbl. The production from the Peruvian fields will doubtless remain for some years at approximately the same level as during the past few years.

Jan 1, 1932

By A. F. Taggart, Nathaniel Arbiter

The chemical reaction occurring in collection of nonmetallic minerals with amine-type collectors was early postulated by students of flotation phenomena to be metathesis between the mineral and the collector, involving exchange between the amine-bearing (aminium) ion and the cation of the mineral, and formation at the mineral surface of an oriented film of the amine salt of the mineral anion. Qualitative evidence of exchange has been obtained on several occasions at Columbia. Thus 1000 C.C. of a solution containing 495 mg of laurylamine hydrochloride was shaken 17 min. with 100 grams of barite and ground in a porcelain mill to pass a 200-mesh screen; the mixture was then set aside for 48 hr. Filtrate therefrom analyzed 476 mg. per liter of laurylamine hydrochloride. There was no substantial loss of chloride ion (78.4 mg. per liter in the original; 74 in the filtrate). No successful analyses were concluded for barium ion. Earlier, confessedly rough work with scheelite indicated a solution gain in Ca++ equivalent to about one-half the aminium ion lost. Real quantitative roof of the exchange, in the form of an established stoichiometric balance, is unknown to the authors. The data of the present paper, however, obtained from experiments designed on the basis of the exchange hypothesis, constitute strong evidence of its truth, and at the same time point the way to economic utilization of the expensive nitrogen-bearing collectors in concentration of the low-priced nonmetallic minerals. The basic postulate underlying the experiments performed was that, if the collecting reaction is of the type R+ + Y- + MX = RX + M+ + Y- where R = aminium ion, Y = the anion of the amine salt, and M and X are, respectively, the cation and anion of the mineral, the reaction should obey qualitatively the implications of the mass-action and solubility-product laws. This is to say that coating and collection should be aided by the addition to the solution of either ion (R+ or X-) of the collector-coating compound, and hindered by the addition of either of the ions M+ or y-. Experimental work comprised determination of (,) the relative solubilities of the laurylammonium salts of a variety of nonmetallic-mineral anions; and (21 the contact angles' of various minerals in solutions containing different concentrations of the postulated controlling ions. Semiquantitative flotation tests were run With barite as checks on the diagnostic character of the contact angles. The amine

Jan 1, 1947

By Nathaniel Arbiter, A. F. Taggart

The chemical reaction occurring in collection of nonmetallic minerals with amine-type collectors was early postulated by students of flotation phenomena to be metathesis between the mineral and the collector, involving exchange between the amine-bearing (aminium) ion and the cation of the mineral, and formation at the mineral surface of an oriented film of the amine salt of the mineral anion. Qualitative evidence of exchange has been obtained on several occasions at Columbia. Thus 1000 C.C. of a solution containing 495 mg of laurylamine hydrochloride was shaken 17 min. with 100 grams of barite and ground in a porcelain mill to pass a 200-mesh screen; the mixture was then set aside for 48 hr. Filtrate therefrom analyzed 476 mg. per liter of laurylamine hydrochloride. There was no substantial loss of chloride ion (78.4 mg. per liter in the original; 74 in the filtrate). No successful analyses were concluded for barium ion. Earlier, confessedly rough work with scheelite indicated a solution gain in Ca++ equivalent to about one-half the aminium ion lost. Real quantitative roof of the exchange, in the form of an established stoichiometric balance, is unknown to the authors. The data of the present paper, however, obtained from experiments designed on the basis of the exchange hypothesis, constitute strong evidence of its truth, and at the same time point the way to economic utilization of the expensive nitrogen-bearing collectors in concentration of the low-priced nonmetallic minerals. The basic postulate underlying the experiments performed was that, if the collecting reaction is of the type R+ + Y- + MX = RX + M+ + Y- where R = aminium ion, Y = the anion of the amine salt, and M and X are, respectively, the cation and anion of the mineral, the reaction should obey qualitatively the implications of the mass-action and solubility-product laws. This is to say that coating and collection should be aided by the addition to the solution of either ion (R+ or X-) of the collector-coating compound, and hindered by the addition of either of the ions M+ or y-. Experimental work comprised determination of (,) the relative solubilities of the laurylammonium salts of a variety of nonmetallic-mineral anions; and (21 the contact angles' of various minerals in solutions containing different concentrations of the postulated controlling ions. Semiquantitative flotation tests were run With barite as checks on the diagnostic character of the contact angles. The amine

Jan 1, 1947

By AIME AIME

NINETEEN states have on their statutes laws requiring engineers practicing within their borders to be licensed sixteen other states have such laws under consideration. While mining engineers are not specifically referred to in every case, they are referred to by implication. In only a few states have mining engineers taken any active interest in this subject, either in support or in opposition, yet it is a matter of very grave importance to them. By some it is thought that it is now too late to take any active steps toward preventing or repealing a type of legislation for which there appears to be a growing demand from some source. And it is further thought that the best course for those who are interested is to endeavor to guide legislation so that the remaining states may enact laws containing as few objectionable features as possible.

Jan 1, 1921

By AIME AIME

ONE test is worth a thousand expert opinions, say the engineers of the John A. Roebling's Sons Co. of Trenton, N. J. Confronted with the job of building the cables for the new Hudson River Bridge between Fort Lee and upper Manhattan, the Roebling organization, in spite of its long and varied experience in building cables for suspension bridges of various sizes, recognized that old yardsticks would be of little value in estimating safety factors for the immense span across the Hudson.

Jan 1, 1929

OFFICERS AND DIRECTORS For the year ending February, 1934 PRESIDENT AND DIRECTOR FREDERICK M. BECKET NEW YORK ,N . Y. PAST PRESIDENTS AND DIRECTORS ROBERT E. TALLY JEROME ARIZ SCOTT TURNER WASHINGTON D. C.

Jan 1, 1932

Jan 1, 1899

By S. T. Sorrell

To obtain a negative determination for prime farmlands in its approved lignite surface mine permit application, Phillips Coal Co. conducted a soils mapping effort and a historic land use survey. In addressing the justification for topsoil substitute materials, the company relied on results of a geochemical evaluation to demonstrate improved drainage, trafficability, and fertility. It also relied on results of field test plots. Post-mining land use was determined through the use of overlay maps considering existing land use, vegetation, and historic prime farmland. The reclamation plan incorporated these elements plus indicator species, existing vegetation, and wildlife needs.

Jan 1, 1985

Jan 1, 1958

Jan 1, 1904

The Committee on Nominations will welcome from members of the Institute suggestions for the offices which are to be filled by election in February, 1018, and which are as follows: 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 VIII, which reads as follows: "The geographical districts to he considered by the Committee on Nominations shall be as follows, until otherwise ordered by the Board.

Jan 8, 1917

By M. Van Hecke, Y. Berube, L. M. de Smecht

Nitrogen solubilities in water at 100, 200, and 400 psi, in the temperature range 100 to 175C, were determined using an automated system involving flash evaporation and gas chromatography. Rates of gas transfer into a standard laboratory auto-clave were measured by the same technique. The rates at which a gas can dissolve into such a reactor were found to be close to the rates of oxygen consumption observed during the oxidation of several mineral sulfides, indicating that gas transfer might be a rate-limiting step in autoclave leaching.

Jan 1, 1977

1944 WALTER HULL ALDRIDGE New York, N Y 1946 PETER M ANDERSON Johannesburg, South Africa 1946 CHARLES CAMSELL Ottawa, Ont, Canada 1946 CHARLES AUGUSTUS CARLOW Fife, Scotland 1949 ERLE V DAVELER New York, N. Y 1951 EVERETTE LEE DEGOLYER Dallas, Texas 1946 CECIL H DESCH London, England 1946 WILLIAM FRASER London, England 1917 HERBERT HOOVER New York, N. Y 1941 DANIEL COWAN JACKLING San Francisco, Calif. 1950 ZAY JEFFRIES Pittsfield, Mass 1939 HENRY KRUMB New York, N Y 1942 ESSINGTON LEWIS Melbourne, Vic, Australia 1944 WALTER C. MENDENHALL Washington, D. C 1942 PAUL DYER MERICA New York, N Y 1938 A M PORTEVIN Paris, France 1934 T A RICKARD Victoria, B C, Canada 1946 JOHN R SUMAN Houston, Texas 1946 WONG WEN-HAO Chungking, China

Jan 1, 1952

By Antonio Marrano, Eda F. Quadros, Diogo Correa [Fo], Paulo T. Cruz

For many years the water pressure test has been used as a normal procedure to investigate the hydraulic characteristics of rock masses and discontinuities. Although the test has given evidence of problematic areas, the nature of flow and the so called equivalent permeability are seldom seriously affected by the testing tecnique. In order to improve the information on these points the Instituto de Pesquisas Tecnológicas de São Paulo - IPT, has developed an extensive program at laboratory and field research on the hydraulics at rock fractures. This paper summarizes the main items related to this research. Is shows that with only small improvements on field tests and some support of laboratory conductivity tests on natural rock joints it is possible to obtain a better understanding of the nature of flow in fractures, improve flow predictions and estimate the opening and hydraulic conductivity, as well as the transmissivity of natural joints or rock discontinuities.

Jan 1, 1982