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In spite of the many contributions that have been made to our knowledge of the creep properties of polycrystalline lead, the precise influence of various factors on these properties is not yet fully understood. Indeed, the position is such that several important points in connection with the creep of lead are a matter of controversy. This has been brought about largely by the fact that, in the case of lead, the changes that are produced in the creep behaviour by slight variations of such factors as the purity, grain sizeand previous treatment are out of all proportion to the magnitude of these variations.In order to study the fundamental properties of lead as related to creep, and so gain a more enlightened perspective with which to consider the creep of lead in general, the work that is described in a series of papers, of which the present paper is the third part, has been carried out. It deals with lead in the form of single crystals.It has been shown (1) - (3) that the grain boundaries as well as the actual grains play a part in the creep of polycrystalline lead. The present work, by eliminating grain boundaries, enables the. contribution of the grains themselves to the process of creep, in other words, crystalline creep, to be studied effectively.This object was, possibly, the major one in this work.

Jan 1, 1940

A new test coke oven of 7 cu. ft. capacity is described. The oven was designed to simulate conditions in a central section of a battery oven and a special feature is the achievement of unidirectional heating from theflues on either side of the charge.The method of charging permits close control of charge conditions such as bulk density and moisture content.These conditions, as well as coking conditions (e.g. flue temperatures and coking time) must be varied to simulate conditions in different batteries. The effects of several variables on coke quality are discussed.Using test oven conditions corresponding to those of Newcastle steelworks batteries, good agreement was obtained between strength indices of test oven and battery cokes. For 17 tests, the average ASTM stability and hardness indices for the test oven coke were 38· 5 per cent and 69·7 per cent, while those for the battery coke were 37· 4 per cent and 67·6 per cent.Observed relationships between coke yield and productivity, and volatile matter and charge moisture are given.The use of a test oven to classify test coals into prime-, medium-, poor-, and non-coking coals is discussed.This may be achieved by observing the effects of the test coal in blends with other coals. The results of a series of blending tests are presented.The dangers of attempting to predict coke quality from a single coal property are pointed out, since this can be done only for very restricted ranges of coals.A diagram is given showing the established trends in the effects of blending various types of Australian coals on coke strength.

Jan 1, 1970

The Pilbara Block is a nucleus of Archaean rocks which lies in the North West Land Division of Western Australia, and it constitutes a mineral province that has been divided into two areas-the West Pilbara Goldfield and the Pilbara Goldfield.In the West Pilbara Goldfield two contemporaneous environments are represented by laterally equivalent volcanic and sedimentary successions which together comprise the Roebourne Group. The two successions are lithologically similar to the classical Warrawoona (volcanic) and Mosquito Creek (sedimentary) successions of the Pilbara Goldfield; but in the West Pilbara Goldfield there is no sign of the erosional break which separates the Warrawoona Succession from the Mosquito Creek succession. The Roebourne Group and the igneous rocks which have intruded it belong to the Archaean Pilbara System.Evidence of preconsolidation movement and igneous intrusion into unconsolidated sediment suggests that tectonism and igneous activity, localized along lines of fracture in an unidentified basement, beganbefore lithification was complete. Movement was primarily vertical, and persisted into the Lower Proterozoic.Vulcanicity and chemical sedimentation, accompanied by a diminution of detr:tal sedimentation, is thought to have caused a relative enrichment in the metal content of the middle part of the Roebourne Group; and the metal may have been remobilized during diagenesis and metamorphism, and localized in zones of dislocation formed both before and after consolidation of the sediments.INTRODUCTIONThe name "Pilbara" has been widely applied in the area under discussion, and to avoid confusion the various uses are summarized below.1. The town of Pilbara, now abandoned, was a centre of mining between 1888 and about 1914. It lies some 90 miles FJSK of Roebourne (Fig. 1).2. The original Pilbara Goldfield was modified several...

Jan 1, 1965

By D M. Menne

This paper is intended to give a general review of current gold extraction technology for free-milling or non-refractory auriferous ores. Fundamental process concepts and some of the differences between the current technologies is referred to. Typical flowsheets and layouts are provided and it is demonstrated that technology for extracting free-milling gold is relatively simple. For environmentally sensitive areas such as encountered in New Zealand relevant cyanide decay and destruction technology is also discussed. Brief mention is made of some likely future innovations. Finally reference is made of New Zealand's previous significant contribution to gold extraction technology. These contributions were pioneering ranging from the cyanide leaching of gold to adsorption by carbon and precipitation by zinc. New Zealand has not allowed its potential gold projects to develop at a rate commensurate with the rest of the world thereby stifling its renowned innovative approach in this technology. It is time for New Zealand mining to recognise its unique opportunities in developing gold extraction technology and again take a rightful place in leading the way.

Jan 1, 1986

The corrosion of aluminosilicate refractories by soda from three different sources has been studied by microscopic methods. Sodium sulphate from oil ash, sodium chloride used in glazing structural clay products, and sodium borate from borax-impregnated wood ash have fundamentally the same effect on the refractories. The soda is the chief medium of reaction and fluxing, the sulphur, chlorine, and boron being volatized as sulphuric, hydrochloric, and boric acids.INTRODUCTIONBecause of their strong fluxing action, alkalis are one of the main causes of corrosion and slagging of refractories.The action of potash and soda on refractories follows somewhat similar lines, although it is common for one alkali to be greatly in excess of the other. The course of the reaction in a number of cases of alkali attack has been studied by microscopic and chemical methods. For example, the action of potash on blast furnace refractories was studied by Kraner (1942) and Rigby and Richardson (1947), who described the occurrence of various potassium aluminium silicates. Its action on cement kiln refractories was described by Brisbane, Segnit, and Weymouth (1957). The action of soda on glass tank refractories has been studied by many people, for example Bisby (1956) and Resch (1954). Clews, Hugill, and Green (1940) made a microscopic examination of the attack by soda on silica bricks from a gas retort.Some recent cases of corrosion of aluminosilicate refractories which were brought to the attention of the Division of Building Research, C.S.I.R.O., illustrate phenomena which occur under conditions different from those...

Jan 1, 1964

By Larkin F, Farrer E, McGhie R. R

The Electrolytic Zinc Company of Australasia Limited commenced productive operations during February, 1936, at the- Rosebery and Hercules mines, which are situated near Rosebery, Tasmania. At this time it was decided that before re-organizing the steel sharpening shop a test should be made of the relative merits of conventional drill-steel and detachable bits. For this purpose Ingersoll-Rand type"I" thread centre hole.jackbits were selected and seventy-two of these were tested against conventional steel. Results indicated that, under the conditions pertaining at these mines, j ackbits should prove more economical than conventional drill-steel bits, and that a large-scale test, under working conditions, should be made. This was done by gradually replacing conventional drill-steel with jackbits at the Rosebery mine. Results were satisfactory and by the end of 1936 both mines were using only the jackbits.

Jan 1, 1939

By Tumilty JA, Schmidt CG

Sulphide ion is a powerful poison in gold cyanidation, however, the detrimental effect is less severe in plant practice. This is thought to be due to the presence of depassivating elements in the ore, mainly lead. Trace amounts of lead can counteract the poisonous effect of considerable amounts of sulphide. The reaction is instantaneous and is likely to be a direct involvement in the electrochemical surface reaction. Lead addition cannot be regarded as an all-round cure when experiencing poor leach efficiencies. A possible beneficial effect depends on the mineralogy of the ore and has to be determined individually for every material.

Jan 1, 1989

The cost of power is an important matter to mining companies generally and this thought that the members of the Australasian Institute of Engineers, as well as the engineering and mining professions generally would be interested in any proposal for the reduction of that cost has led to the presentation of this paper.The writer trusts that the description will be found clear and increase the interest in this interesting subject. In the up of the electrical arrangements touched on in this paper, the author has had the able assistance of his friend Mr. Mars, to whom he offers his hearty thanks. The selection of the best class of power plant for a mine is a very difficult and large problem and it is quite out of place to dogmatise that anyone of the many systems that offer is better than another, eg that the all electrical is better than the partly direct steam-driven and partly electrical, or that a gas plant is better than a steam plant. Such a selection is one that calls for very careful and close consideration, in each particular case, of a large number of before it is possible to arrive at a proper decision.

Jan 1, 1912

By Edwards A. B

A suite of specimens from the newly developed Black Star copper ore body at Mount Isa was made available for mineragraphic study by the Mount Isa Mines, Ltd. The specimens were selected as representative of the different phases of mineralisation found in the ore body, rather than with a view to furnishing a complete cross-section of it; and the examination has been carried out with a view to ascertaining (1) the nature, extent and association of the arsenic, antimony and possibly bismuth, minerals in the ore, (2) the mode of occurrence of silver in the ore, and (3) whether galena and sphalerite occur in minute forms well below the sIzes readily observed in hand specimens.Analyses of the January to June, 1944, mill head composites show that the proportions of the elements Ag, As, Sb and Bi in the ore are as follows:Ag 0.000013 = 0.35 oz./tonAs 0.024Sb 0:002Bi 0.0005The copper content of the mill heads ranges from 3.5% to 4.75%, the lead content from 0.03% to 0.08,% and the zinc content from 0.09% to 0.23%.MINERAL COMPOSITIONThe specimens range from massive sulphide ore, consisting of areas of chalcopyrite, pyrrhotite, and rarely sphalerite, from 1 to 3 cm. across, to fragments of extremely finely banded pyritic shale in which no minerals other than pyrite are visible. The gangue associated with the massive sulphides is chiefly dolomite, and sometimes white quartz. The pyritic shale fragments show evidence of shearing and faulting on a micro-scale, the fractures sometimes being filled with sulphides and vein minerals.The ore minerals found in the polished sections are pyrite, arsenopyrite, marcasite, sphalerite, chalcopyrite, valleriite, chalcostibite, galena, dyscrasite, jamesonite, magnetite, gold, graphite and rutile.Pyrite (FeS2)Pyrite occurs chiefly in two forms according to whether deposition took place along the bedding planes or along the intersecting faults and fractures. Deposition of pyrite along the bedding planes of dense, thinly banded shales ha,s produced a metasomatically altered shale in which the pyritic bands are from 0.02 to 0.03 mm. wide, and alternate with bands...

Jan 1, 1945

The maximum current density at which conventional copper electrowinning plants will result in satisfactory, adherent, and dendrite·free cathodes is determined by the thickness of the diffusion boundary layer. A decrease in the value of that thickness will permit an increase in the current density. This fact is utilized to develop a high current density cell in which the reduction of the boundary layer thickness is accomplished by means of a specially designed electrolyte circulation system. The high current density cell is used to determine the effect of current density on such process parameters as current efficiency, cell voltage, power consumption, and cathode purity. A number of empirical equations are developed for the purpose of estimating the magnitude of these effects.

Jan 1, 1972

By King R. L

Low-enthalpy geothermal groundwater resources occur at relatively shallow depths in the Upper Cretaceous/1'ertiary sedimentary sequence in the on-shore Gippsland Basin. The main stratigraphic unit containing hot groundwater is the Latrobe Group. Groundwater temperatures in the range 30 to 70¦C have been recorded from depths between 500 and 1000 m. The hottest groundwater is in the Latrobe Valley and Lake Wellington depressions. Geothermal gradients in these areas range from less than 2¦C/100 m to over 10¦C/100 m (compared to a world average of about 3¦C/100 m). A number of theories have been advanced to explain the geothermal anomalies including exothermic reaction such as oxidation of coal, mixing with deeper, hotter groundwater and high geothermal fluxes along fault zones. Variations in geothermal gradients can also result from type and thickness (and hence thermal conductivities) of the sedimentary pile, depth to consolidated basement rocks, and influence of groundwater flow patterns including proximity to recharge zones. The hot groundwater in the Gippsland Basin has substantial potential as a source of energy for direct heat applications such as process heating, space and water heating for buildings, and agricultural and aquaculture. Geothermal energy has a number of environmental advantages over traditional sources of energy. It is clean, safe, causes minimal land disturbances and in most cases is naturally renewable.

Jan 1, 1992

By Misra V. N, Cheng C. Y

Two types of Mt Tom Price hematite iron ore from Hamersley Iron P/L were tested using a Humboldt Wedag Jones P40 wet high intensity magnetic separator (WHIMS). The parameters tested were magnetic intensity (7000, 9000 and 11 000 Gauss), groove plate type (8R and 12R) and gap width (2.5 and 1.8 mm). It was found that at 9000 gauss magnetic intensity, reasonably high-grade and recovery in the concentrate were obtained. At 2.5 mm plate gap width, the 12R groove plate performed slightly better than the 8R groove plate. Further testwork is recommended to optimise the magnetic intensity, feed flowrate and pulp density, wash water pressure and flowrate with 12R and 8R groove plates at 2.5 mm gap width.

Jan 1, 1999

THIS tunnel, which is an adit 7000 ft. long, was undertaken by the Mount Lyell Mining and Railway Company Limited to connect its treatment works with the North Lyell mine at depth, with a view to effecting economies in transport and drainage. The work was carried out at high pressure throughout from both ends, and although the ground in the mine end was intensely hard, good progress was made, and driving was completed in less than fifteen months.The Mount Lyell mining field is situated in the west of Tasmania, about 20 miles inland, the only means of access being the Mount Lyell Mining and Railway Company's 3 ft. 6 in. gauge railway which connects with the Government railway system of the State at Strahan, on Macquarie Harbour. The region is mountainous, and presents many difficulties to the road and railway engineer. The West Coast range running north and south in a succession of bold prominences, which rise up to 4000 ft. above sea-level, forms the backbone of the district, and on its foothills the Mount Lyell mines are situated. The railway terminus at Queenstown...

Jan 1, 1929

Factual data about the sedimentation in the Newcastle Coal Measures are presented. Data concerning the total coal measure sequence (isopachs, sand/shale ratio, and total coal thickness variation), data about three coal seams (Borehole, Dudley, and Victoria Tunnel) and data about interseam conglomerate units are discussed.From this data conclusions are drawn about the coal measure environment. The western edge of the coal basin, the Lochinvar Dome, although a high feature, was apparently stable during coal measure time. Despite its height it apparently supplied little sediment to the basin.The northern and north-eastern edge, which was unstable, supplied most of the coarse detritus (including the conglomerates) to the basin. The conglomerates show patterns of fluvial origin but after a period of "normal" variations in pattern they become restricted to two parallel zones evidently tectonically controlled. Deposition of conglomerates is episodic and separated by periods of coal formation when deformation was apparently slight. Formation of each of the three seams considered followed a rather similar pattern- each show development of thick coal around the basin edge and poor thin coal in the "axial" region of the present synclinal structure.Evidence of ill situ formation of some areas of the seams is discussed and periodic deformation of the basin during coal measure time is postulated.The unusual character of this coal basin, in particular the very coarse units, is stressed, despite the presence of many "normal "coal basin features.

Jan 1, 1970

FROM time to time articles have appeared in the technical press on the interesting subject of surface combustion. The theoretical part of the problem has, for practical purposes, received ample consideration in those articles, but the number of practical applications of surface combustion referred to has generally been very small.It is the writer's object to review some recent developments in surface combustion, and also to try to arrive at an estimate of its advantages and possibilities. It is not necessary for this purpose to dilate upon the phenomenon of surface combustion itself. Many interesting things have been said on the subject by Pro£. W. A. Bone, of Leeds, to whose researches the recent developments are largely due. A few illustrations may make clear what is meant by surface combustion.Prof. Bone, in an experiment, took a platinum crucible, which he heated in the flame of a Meker-burner. Then he turned the gas off for a second, and, opening the stop-cock again, allowed the combustible mixture to impinge upon the crucible, thetemperature of which was still well below the ignition temperature of the gas. Although no flame was visible at this stage, it was soon clear that, nevertheless, the gas and air had continued to combine, as the crucible would attain a red heat after a few seconds.Another instance of surface combustion was shown by a Mr. Fletcher, in 1882. He placed an iron ball, weighing 3 lb., on a slab of fireclay, heated it for a few seconds with a blow-pipe, and blew the flame out, leaving the gas-mixture still...

Jan 1, 1915

In general, the metallurgical industry has so far been slower than the chemical industry to adopt ion exchange materials for industrial processes. The atomic energy industry presents a marked exception to this general situation, and the literature shows a rapidly increasing use of ion exchange techniques for the recovery of atomic energy metals on scales ranging from the ultra micro up to that of the largest mining operations. In many cases, the processes used would be equally applicable to more common metals and it is hoped that this review will be of interest to metallurgists outside the specialised atomic energy field. The review is intended to describe developments of ion exchange processes made during the last three years. Earlier studies have been summarised by Kunin and Preuss (1956) and Roland (1957). In order to restrict the number of references discussed, purely analytical procedures have been omitted and only those processes which have been conducted on a reasonably large scale or which, from their nature, areclearly capable of being upscaled, have been considered. The paper is divided into five main sections concerning respectively:Water treatment and effluent disposal.Metal recovery and purification.New ion exchange materials.New ion exchange equipment.Membrane cells.WATER TREATMENT AND EFFLUENT DISPOSALA high proportion of atomic reactors, and particularly those of American design, are cooled by water which is...

Jan 1, 1961

By Colwell J. B, Constantine A. E

A unique, regional grid of deep (12 - 14 second record length), seismic reflection and refraction data has been recorded by the Australian Bureau of Mineral Resources (BMR) across the offshore Gippsland Basin and parts of the adjacent Bass Basin, in southeastern Australia. These data have been combined with onshore mapping to produce a new model for the development of the Gippsland and adjacent Bass Strait basins. Overall, the Gippsland Basin contains up to 12 - 14 km of sediment in an ESE-trending depocentre bounded on its north and northwestern margins by a detachment ramp, and on its southern side by a relatively linear, listric fault system. The basin, together with the adjacent Bass and Otway Basins, appears to have formed as part of a linked, largely- strike-slip to 'transtensional' system, which started to extend through Bass Strait, probably during the latest Jurassic. Each of the basins developed by movement on a common detachment or detachment complex, which produced headwall extension at their western ends, in the areas now occupied by the Strzelecki Ranges, Otway Ranges - Torquay Sub-basin, and Robe Trough. Adjustments and reactivation from the mid Cretaceous of several postulated microplates in the region, largely in response to Tasman Basin rifting, gave rise to the wrench-related and compressional structures which form the major petroleum targets in the Gippsland Basin. However, the same process formed largely extensional stuctures in the Bass Basin. Our interpretation of the tectonic history of the Gippsland Basin leads us to the conclusion that there may have been several phases of petroleum generation and migration, and that potential petroleum traps appear to exist in the deeper section, in structures sometimes not reflected at the top or near-top Latrobe Group levels.

Jan 1, 1992

On-stream determination of xanthate concentrations can be made by photometric measurements at 313 nm.A simple double-beam instrument was developed for this purpose. A mercury lamp is used as the light source and a composite filter of UGll glass and chromate solution is used to isolate the required spectral region. The light beam is split into two components of approximately equal intensity. One component is passed through a reference cell containing water to a photo detector; the other component is passed through the xanthate solution to a second photo detector. The reference signal controls amplifier gain to eliminate effects of lamp intensity changes and the amplified sample signal can then be used to measure xanthate concentration.Plant trials showed that provided a clear solution free of air bubbles was obtained from an on-stream filter, the instrument indicated the xanthate concentration and operated satisfactorily for long periods.

Jan 1, 1973

By Lonie W. M

The rapid development of the Australian steel industry over the past twenty years has greatly increased the demand for coking coal from the collieries owned by the Broken Hill Proprietary Co. Ltd. and Australian Iron & Steel Ltd. This in turn has called for an intensive and continuous programme of colliery expansion and new colliery development, along with the reorganization and modernization of existing collieries.This paper presents a general description of the factors involved and the techniques used in planning modern colliery development for the steel industry.PRELIMINARY GEOLOGICAL INVESTIGATIONSIn any colliery development, preliminary geological investigations require a detailed and practical knowledge of the geology and characteristics of the coal-field as a whole. In the early stages of the investigations, probably the most valuable information is obtained from outside the particular area under review, rather than within it, and unless the geology of the coal-field is understood, the projection of the known information into the unknown area cannot be carried out with certainty.Because development of the coal seams from the outcrops has been an apparently simple matter and not subject to the risks involved in deep mine development, the geology of the New South Wales. coal-fields has not received the attention that major mineral resources warrant.Only the most accessible regions of the coal measures have been generally prospected, while the potential areas remain...

Jan 1, 1957

Principal component analysis of the variation of Cu, Ni, Zn, Pb, Mn, and Cr in a control group of 96 samples of surface ironstone from the Yilgarn Block, Western Australia, was used to derive a simple graphical method, based on only Cu, Ni, and Cr, for discriminating between massive nickel gossans and other ironstones.When the graph was tested by plotting 400 control samples, it failed to correctly classify only nine out of 176 gossans and 11 out of 224 other ironstones.

Jan 1, 1974