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THE education of adolescents to perform the duties and assume the responsibilities of maturity has been a characteristic of human society since the dawn of history. In the beginning the members of the immediate family performed this function, and in modern life they still have an important part in it. Possibly religion was the first field in which education began to be functional; young people were sent for instruction to a teacher who had a broader and deeper knowledge of the subject than was possessed by the family. It does not seem necessary for our purpose to attempt to determine how, when, or where instruction in the practical arts first began to become functional, and the brief outline which follows must suffice. The discovery and utilization of mineral substances to improve and maintain the conditions of human living is a practical art, which must have had an almost accidental origin and have been developed by empirical experiments. We do not know, nor would it be useful to try to fancy, how men first learned that they could make use of mineral substances to their benefit, but however that knowledge was initially gained it was certainly trans- mitted through instruction in the family. At fist such activities must have been merely a minor part of the making of a living, bit in time those who excelled found it better to devote them-

Jan 1, 1941

By B. J. Scheiner

Extraction of molybdenum from molybdenite ore by an electrolytic oxidation procedure was investigated by the Bureau o f Mines. Various parameters affecting molybdenum extraction, such as salt concentration, temperature, treatment rate, current density, and particle size, were studied. Molybdenum extraction of 95.2 percent was achieved on a laboratory scale from an ore containing 0.35 percent molybdenite. Corresponding power consumption was 24 kwhr per pound of molybdenum extracted with a base consumption of 4.5 pounds of sodium carbonate. Laboratory and pilot plant experiments are in progress on low-grade molybdenum concentrates containing rhenium and copper. Preliminary results indicate that molybdenum extractions in the 90- to 99-percent range and rhenium extractions of 93 to 99 percent can he obtained without appreciable oxidation of associated copper minerals.

Jan 1, 1972

By Schrade F. Radtke

The future of lead and zinc, as with any material, will relate directly to their capability to remain competitive; that is, to demonstrate cost-performance ratios that are superior to those of competing materials. These cost-performance ratios are not static; therefore, it is necessary to develop improvements in products or processes to maintain present markets or to penetrate other markets. Perhaps the surest way to achieve these goals, if they can be achieved at all, is through research. The world lead and zinc producing industry established ILZRO as its cooperative research function to carry on both fundamental and applied research and development efforts aimed at the stated objectives. Current research efforts in the fields of die casting, galvanizing, finishing, chemicals, architectural applications, ceramics, and batteries are reviewed and potential impact assessed, some projections are given of possible new areas of research. Environmental research and its impact on future uses of lead and zinc are also discussed.

Jan 1, 1977

Carbonate-hosted massive sulfide ores of the American cordillera compose a distinctive genetic class. Discordant fea-tures of occurrence together with measured high-temperatures of formation indicate their essential epigenetic character and close spatial association with centers of thermal activity during evolution of the cordillera. Their metallogenic character is complex from region to region: Cu-Zn-Pb-Ag, Pb-Zn-Ag, and Cu-Zn-Ag-Au represent extremes of composition and each may be identified with specific terranes of occurrence, notwithstand-ing an inferred common process of formation. Beyond the presence of a thermal center, other controls that may be identi-fied include apparent but obscure properties of primary perme-ability or chemistry of hosting strata, and secondary controls are imposed by stratigraphic differences in which permeability is strongly contrasted. Structures that act as channelways may be identified in some instances. Notwithstanding their intrinsic value, search for these ores is difficult and requires the solution of complex geochemical and three-dimensional geometric problems.

Jan 1, 1990

By J Zhou, D M. Hunter, S M. Iveson, K P. Galvin

The REFLUX Classifier is used to perform particle separations on the basis of density utilising a set of parallel inclined channels positioned above a vertical fluidised section. In continuous mode, feed enters part way up the vertical section, while fluidisation water is introduced from below. Lower density particles are conveyed upwards and collected in an overflow stream, while high density particles segregate onto the inclined surfaces, settle to the base of the system and empty via an underflow stream. Pressure transducers are used to measure the suspension density in the vertical section. This suspension density is maintained by a pneumatically controlled underflow valve to maintain a target suspension density or ‘set point’.Previously, Galvin et al (2010) demonstrated the significant improvement achieved via a new laminar-shear separation mechanism, achieved by utilising closely spaced inclined channels in the REFLUX Classifier. For the separation of low-density coal particles from mineral matter, a channel spacing of 6 mm proved effective; however, for the separation of gangue minerals from much higher density minerals such as iron ore, the shear-induced lift needs to be even higher. In this paper, we examine the influence of two different channel widths on the continuous processing of an industrial iron ore feed in the REFLUX Classifier. It was found that when moving from 6.0 mm to 3.0 mm channels, the ability of the system to reject coarser gangue material and retain finer high density material across a particle size range from 0.125 to 1.0 mm was increased, resulting in a higher grade product.CITATION:Hunter, D M, Zhou, J, Iveson, S M and Galvin, K P, 2017. Influence of shear rate on separation of iron ore fines using the REFLUXTM Classifier, in Proceedings Iron Ore 2017, pp 205–210 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Burton H. Boyum

GREATER depth of exploration drill holes and increasing cost of drilling have been principal factors in reviving interest on the Marquette Iron Range in controlled directional drill-hole deflection. This deflection is obtained by the application of the Hall-Row wedging technique. Modifications were made in the technique and equipment in the effort to simplify and strengthen the procedure. The practice is similar in many respects to the oil well type of deflection with a whipstock.

Jan 1, 1947

By B. S. Terry, C. L. Harris

After measuring the kinetics of Ni reduction from a SiO2-saturated fayalite slag into a Cu-based metallic phase on a laboratory scale, a general model was developed that is capable of simulating mass transfer to and from metal-slag, slag-gas and metal-gas interfaces for multiple species. The model was used to simulate the reactions that occur when Cu and Ni are reduced from fayalite-based slags into a Cu-based metallic phase. Good agreement was achieved between model predictions and experimental data

Aug 1, 1995

By C. Willard Hayes

The determination of the question whether the Mayari and Moa mining-claims of the Spanish-American Iron Co. have been rightly denounced under the third section of the law of bases rests on the findings in the following questions of fact: 1. Is the mineral an iron-ore ? 2. Is the iron-ore a bog iron-ore ? 3. Is the iron-ore ocher ? 4. If ocher is present, can it be mined separately and independently of the iron-ore ? 1. Is the Mineral an Iron-Orb? Since the material is shown by a large number of analyses to contain from 41 to 50 per cent. of metallic iron and less than

Jan 1, 1912

Evaluation of Comminution Circuit Design for Sustainability Using EcoNomicsTM

Sep 13, 2010

By W. G. Matteson

The Gulf Coastal plain of the southern United States is that area bordering for a large part, the Gulf of Mexico and extending inland and northward to the main interior highland region. It is more or less V-shaped and includes the States of Florida, extreme southern Alabama, all .of Mississippi and Louisiana, the eastern and southern half of Arkansas, and the eastern, southeastern, and southern portions of Texas. While the contents of this paper apply to. the Gulf Coastal plain in general, they are intended to refer more specifically to that portion of the plain included between the 90th and 97th meridians, and the 29th and 33d parallels, an area that may be described geographically as comprising western Mississippi, all of Louisiana, part of eastern and all of south-eastern Texas. It is within this area that numerous and prolific oil pools have been developed during the last 17 years.

Jan 2, 1918

By J. B. Elizondo

This paper, which describes mining methods and practices at the Piokee mining unit and the Piokee expertmental mining project of The Eagle-Picher Co. in northeast Oklahoma, is one of a series being prepared by the Federal Bureau of Mines on mining methods, practices, and costs in various mining districts of the United States. The Piokee unit, comprising the Piokee, Rowe, Lucky Syndicate, and parts of the Netta White and Otis White leases, is in the SW1/4, W1/2NW1/4SE1/4, and W1/2SW1/4SE1/4 sec. 17, T. 29 N., R. 23 E., Ottawa County, Okla. (figs. 1 and 2), The 200-acre tract is adjacent to the town of Picher and near the heart of the Picher field of the Tri-State zinc-lead mining district.

Jan 1, 1959

By Y Peng, D Wannas

In the fine particle flotation technologies being developed today the fine hydrophilic (gangue) particles are usually well dispersed. These highly dispersed fine particles can be recovered into the flotation froth product by mechanical entrainment. Flocculation of hydrophilic particles caused by polymer depressants could potentially reduce the mechanical entrainment of these particles. This paper reports testwork completed on fine particles of several solids, iron oxide, hydroxylapatite, galena and sphalerite, as well as on a relatively coarse quartz sample (-75+38 ¦m). Dodecylamine was used as a collector for the quartz, and several dispersants and polymer depressants, including sodium silicate, sodium metaphosphate, zinc sulfate, potassium dichromate, corn starch, corn dextrin and carboxymethyl celluloses (with molecular weights of both 700 000 and 80 000) were used as flotation modifiers. The major part of the testwork involved flotation tests in a 200 ml flotation column. Both water and solid recoveries were recorded. The degree of flocculation and dispersion was determined by settling tests in 250 ml graduated cylinders. It was observed that flocculation of the fine hydrophilic particles significantly reduced their mechanical entrainment, while dispersion severely aggravated it. Thus, in the flotation separation of artificial mixtures of the -75+38 ¦m quartz and fine iron oxide or hydroxylapatite, polymer depressants that caused flocculation were found to perform better than the ones that did not cause flocculation.

Jan 1, 2005

Thrusting is well documented in the Finisterre/Sarawaget moun- tains, the Kainantu-Waf district and in the Highlands between the Kubor Anticline and the Ramu Valley, Papua New Guinea. The thrusts trend NW and involve rocks ranging in age from Permo-Triassic to Plio-Pleistocene. Evidence from the Finisterre/ Sarawaget mountains demonstrates that a major phase of thrust- ing commenced in Pliocene times and continues today. Palaeostress analyses is a sensitive technique for assessing the kinematic history of faulting. The picture gained from the Finisterre/Sarawaget mountains, the Kainantu district and be- tween Kundiawa and Keglsugl is simple, involving a north to northeast ol. Local complexities between the upper Chimbu Valley and Brahmin indicate extension on a NW-N trend. The simplicity of this anlaysis, which accords with seismic and geo- detic strain data, shows that the major faulting in Papuan Orogen is no different from that in the Papuan Fold Belt; that the Papuan Orogen and the Papuan Fold Belt together form a young thrust- fold complex; and that such structures as the Kubor Anticline may be fault-bend folds. Recognition of the obduction of the Finisterre/Sarawaget reef/ volcanic complex over the Australian plate, the gas seeps in the Ramu Valley and foothills of the Finisterre/Sarawaget Mountains, oil seeps in the Goroka and Kundiawa regions, and our interpre- tation of the PNG Orogen as part of the Papuan Fold Belt indi- cates unexpected probability that the PNG Highlands are pro- spective for hydrocarbons.

Jan 1, 1997

By Li. L.

Backfilling has become a popular solution in underground mines around the world. It reduces environmental impact of mining industry and improves ground stability. In most cases, backfill has a high water content so that it can be delivered by pipes from a backfill plant on ground surface to underground stopes. Upon deposition in the stope, the backfill tends to consolidate under its own weight, leading to a generation of excess pore-water pressure. To avoid excessive pressure and protect the backfill barricade installed at the base of the stope, the backfilling of the stopes is usually divided into two stages: plug pour and backfill body pour. The interruption of backfilling operation is undesirable as it slowdowns the mining productivity, and sometimes causes pipe clogging, leading to unexpected increase in manpower cost and further reduction in mining productivity. The backfilling interruption time may be reduced, even eliminated if the drainage of backfilled stopes is sufficiently improved. This paper presents an application of wick drains, a material commonly used in civil engineering, to mine backfilled stopes to help accelerating the drainage. A protocol is proposed for installing the wick drains in a mine stope to be backfilled. Numerical simulations were made, showing that the drainage of the backfill can significantly be improved by the introduction of wick drains. The application of wick drains in mine backfill can thus be considered as a promising technique and merits deeper and more detailed investigation.

Aug 1, 2013

By W. H. Emmons

THIS paper is the third of a series treating of the relations of ores of the metals to igneous rocks. The first1 outlined the general problem; the second2 proposed a classification of lode ores, and showed how the distribution of the deposits is in a certain measure controlled by the contour of the roof of the parent batholith. A number of mining districts were discussed, the examples being selected chiefly from group 2 of the classification. The proposed classification of lode deposits, briefly stated, is as follows: 1. Cryptobatholithic: near hidden batholiths which have not yet been exhumed by erosion. 2. Acrobatholithic: in and near cupolas or domes of batholiths-the high points of larger underlying masses. 3. Epibatholithic: on batholiths, near their rims, but below eroded cupolas, or below the highest points of the roofs. 4. Embatholithic: among closely-spaced outcrops which probably are parts of a single batholith. The outcrops of invaded rocks predominate. 5. Endobatholithic: in and near roof pendants of large batholiths. The invading rocks predominate. 6. Hypobatholithic: in deeply-eroded batholiths, where even roof pendants, have been -eroded. Deposits of certain metals on the roofs of the batholiths are much more numerous in some positions than deposits of other metals, and the horizontal zonal arrangements of lodes of different metals are shown characteristically only in certain groups. In a large measure, also, the character of the fracturing and metallization is determined by, the-position on the roof, of the batholith.

Jan 1, 1927

By J. A. Holmes

It is a fact that is coming to be more widely recognized by the general public, as well as by members of the medical fraternity, that the health of persons living in our hill-country depends in no small degree upon the drinking water obtained, just as it has been found that the* use of pure water in the lowlands and swamp-areas of the Southern States results in practical immunity from malarial diseases. Hence the problem, how to obtain supplies of wholesome water for the towns and manufacturing establishments in the hill-country or Piedmont plateau-region of the Southeastern States, becomes one of considerable interest, the importance of which will continue to increase, as the favorable conditions for manufactures and agriculture in this region will make it, in the near future, the most thickly populated portion of the South Atlantic States. Water-supplies from Surface-streams are unquestionably of the first importance; and in the mountain counties, where the region is still largely forest-covered and the streams are swift and continually aerated by rapids and cascades, the water is of superior purity and clearness. This statement is also applicable to the more elevated and sparsely settled portions of the Piedmont plateau; but in the less hilly and more thickly settled portions of this region the streams are more sluggish, and the waters more muddy and less pure, owing to the fact that a much larger proportion of the surface is under cultivation.

Jan 1, 1896

By Reynold N. Hoover, Davis S. Shatzer

The Bureau of Alcohol, Tobacco and Firearms (ATF) is responsible for the regulation and enforcement of the explosives laws codified in the Organized Crime Control Act of 1970, Title XI. To meet its responsibilities ATF has special agents, inspectors and specialists who regularly interact with the explosives industry. However, with just over 2,000 special agents and 800 inspectors and specialists, it is difficult to visit the almost 10,000 explosives licensees and permittees in the United States.

Jan 1, 1995

By J. G. Mravec

The SO-called gas-tube method as developed by Hare, Peterson and Soler for determining the type and content of gases in molten steel is particularly adapted for determining the hydrogen content in molten steel. The development of this method has been quite completely discussed in a paper published by these co-workers in 1937.' The purpose of this paper, therefore, is to familiarize with this method those who arc not well acquainted with it. The principle of the gas-tube method is as fol1ows: One end of an evacuated gas tube is sealed with a very thin copper disk. when this end of the tube is immersed in a test spoonful of molten steel, the copper disk melts almost immediately, allowing a portion of the steel to be drawn up into the evacuated space. Any dissolved gases, and those produced by reactions between the components of the steel during freezing, are liberated into the unfilled portion of the sampling tube. A blob of steel that forms on the immersed end of the tube after the sample is drawn up seals up the end, making it airtight again. The evolved gases are subsequently drawn out of the gas tube through a suitable valve and analyzed by means of an Orsat apparatus. The volume of the sampling tube is sufficiently large so that a pressure considerably below atmospheric is produced after the gas evolution. The low pressure is necessary to effect a nearly complete removal of gases from the steel. Construction oF Sampling Tube The sampling gas-tube apparatus is illustrated in Fig. I. Seamless S.A.E. tubing used for section A is first cut into 7-ft. lengths. Through cxperiencc it was found necessary to use two sizes of tubing for this part, "is-in. and 3/4-in., respectively. The smaller tubing is generally used on the hotter or lower carbon steels. If the inside wall of the tube A is coated with grease or oil, it should be burned out before being machined as follows: One end is machined on the inside diameter to a depth of 34 in., so as to form a seat for a 7/8-in copper disk, which is stamped out from 0.005 to 0.007-in. thick copper sheet. The other end is machined on the outside diameter to a diameter of 1 5/16 in., to take a small reservoir or trap member I?. About 4 in. below the same end, a 1/2-in. hole is drilled to receive the 1/2-in. copper tubing leading to the large reservoir C. The inside of tube A is then thoroughly cleaned with a round wire brush, such as is generally used to clean out shotgun barrels. It is very important that the surface be absolutely free of rust or any nonmetallic coating. Next, the thin copper disk is soldered in place with low-melting silver solder.

Jan 1, 1945

By K Jupp, T J. Howard

Cliffs Natural Resources Pty Ltd (CNR) operates iron ore mines in the Koolyanobbing region of Western Australia. Ore is mined from three locations, separated by many kilometres. The ore is stockpiled at these locations, according to an in-house ore classification system (based on grade and source) and then trucked to the crushing and screening plant at Koolyanobbing. Lump and fines products are railed to Esperance for ship loading and export to Asian customers. CNR prides itself on the relatively low inter-shipment grade variability of the products. The Koolyanobbing crusher is fed using a daily blend plan, generated to maintain lump and fines product grades within acceptable tolerance ranges around targets. Achieving low variability requires predicting lump and fines grades as accurately as practical from the estimated head grades of the ROM ores potentially going into the blend. The grade prediction model may be either a direct prediction of crushed lump and fines grades and lump percentage, or be split into two stages: the bias between blasthole estimated head grade and crusher head grade and then the lump-fines algorithm for splitting the head grade between lump and fines products. The lump-fines algorithm comprises the percentage of lump and the difference between the lump and fines grades. We describe a weighted least squares (WLS) regression model for predicting crusher grades and lump proportion from the estimated head grade for Fe, P, SiO2, Al2O3, Mn and S. The method is applied to CNR production data, where the regression model explains approximately 60 per cent of the variance in the crushed ore grade, for both lump and fines. A further small but significant improvement in prediction can be achieved by including the ore classification data in the model. The regression errors exhibit strong positive serial correlation, indicating trends in grade error across multiple blend records. To compensate for the longer-term error, an exponentially smoothed model was developed and applied to the daily grade blend errors. This gave an increase in the longer-term variance explained and therefore an improvement in grade prediction.

Jan 1, 2009

By Henry M. Howe

HENRY M. Howe, Bedford Hills, N. Y. (communication to the Secretary.) +-Mr. Johnson's explanation, that the rounding of the graphite masses in oxygen-bearing cast iron is clue to their being in part re-precipitated after re-solution in forming carbonic oxide temporarily with that oxygen, is certainly most attractive and suggestive. It remains to be shown whether this rounding occurs also when 'the solidiification is too rapid to permit this process to goon. J. E. Johnson Might easily test this by casting a single ladleful of his oxygenated iron in masses of varying size. If' this present hypothesis is true, then the rounding ought to increase progressively with the size of the casting, and with the distance from the outside, that is to say with the time available for re-solution and re-precipitation. I question whether a like benefit is to be expected even on this hypothesis, from the oxygenation of steel. The spheroidizing of graphite does good because graphite itself is so weak. But the constituent which can be spheroidized in steel is its cementite, which is a source of strength. Lamellar pearlite, in which this cementite in effect forms long dendrites, is far stronger than divorced pearlite, in which these dendrites have been broken up into spheroids. Even the surfaces of contact between ferrite and cementite are probably sources of strength because of the amorphous iron which probably fills them.

Jan 1, 1917