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Since its inception in 1962, the Julius Kruttschnitt Mineral Research Centre has adopted the view that an effective method of training highly qualified engineers for the mineral industry is the pursuit of postgraduate research programmes conducted in operations, that is, in the mines and processing plants of the industry which the research serves. The paper describes how this is achieved in practice, at little or no cost to the taxpayer, and explores the strengths and weaknesses of this approach in the context of a dual mission for the Centre: 1. The postgraduate training of engineers for the mineral industry. 2. The production of useful R &I) for the mineral industry. Topics discussed include financing, relationships with industry and Government, the maintenance of academic excellence, research style, the marketing of research, and limits to growth.

Jan 1, 1989

Nowadays, technology has improved to extract dimensional stone blocks at quarry sites and also to process these at processing plants for making slabs and tiles. In the process of quarrying and processing, performance evaluation of machinery is very important to achieve optimum output at minimum cost with improved technology. Cost analysis of improved technology includes parameters such as manpower, energy consumption, tool consumption, depreciation, maintenance and also others. The chainsaw machine with long boom and rail in marble quarries and multi-diamond wire saw machine for slab making from granite blocks at processing plants have recently been introduced in India. Thus, a study was carried out under a research project on these machines to assess their suitability. In this paper, performance evaluation and cost analysis of chainsaw and multi-diamond wire saw have been carried out with existing machines on the basis of research findings.

Dec 6, 2010

Knowledge of true block grades is obtained from a mathematical model of an orebody, simulated with sample grades normally distributed and spatially correlated according io a spherical semi-variogram model.The superiority of kriging to the polygonal method of estimation is demonstrated on this modelled deposit by comparing the true values with the kriged and polygonal estimates obtained from sampling the deposit. Finally, selection of blocks of the deposit on the basis of the estimated values, shows that if kriging is used, what is predicted is largely mined, whilst if the polygonal method is used large biases can occur depending on the position of the cut-off grade.

Jan 1, 1978

A slag-metal equilibrium study of the system SnO-FeO-(Si02+Al2O3)/Sn-Fe was carried out at 1250°C. The distribution coefficient, k =(Sn/Fe)metal X (Fe/Sn)slag was found to range from 246 for an iron contentof 0·53 per cenrt in the metal to 82 for an iron content of 6·4 per cent. The value of the ratio ?SnO/?FeO was calculated and found to be approximately a function of per cent SnO in slag alone in the region (Si02+Al2O3)/ FeO = 0·4 to 1·2. Comparison with other published work suggests that the addition of CaO to slags having (SiO2+Al203)/FeO ratios of about 1·1 raises the value of ?SnO/?FeO...

Jan 1, 1974

By P M. Hancock

The West Coast contains one of the world's giant placer gold deposits with production since the 1860s totalling some six million ounces (present day value NZ$ 3.6 billion). The deposits have been worked variously by hand, ground sluicing, hydraulicking and/or elevating, blocking out, deep leading and bucketline dredging. Since the sharp gold price rise of 1979 - 1980 gold production has increased steadily (in spite of the closure of the Kaniere dredge) to some 30 000 ounces (933 kg) in 1984. Production is primarily from some 100 medium scale mining, operations treating 50 - 200 000 m3 of auriferous late Pleistocene fluvial gravels year. In spite of their economic value the deposits remain only poorly investigated and many fundamental questions relating to the origin and formation of the deposits remain unanswered. This paper attempts to describe the geology of the deposits and outline a genetic model for their formation, and then discusses some of the economic aspects and current limitations and opportunities of the growing alluvial gold mining industry of the region.

Jan 1, 1985

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

THE present article makes no claim to be exhaustive, since it cannot contain all the knowledge which scientists and manufacturers of the compounds of the rare earths have gained. The following notes are, therefore, simply an attempt to ascertain andclearly record the occurrence, properties, and uses of the more important of the rare earths, with a special reference to their commercial values and the industries based upon them.HISTORYIt was the mine manager, Gcyer, of Stockholm, who, in 1788, first drew attention to a black mineral which had been found in a quarry near Roslagen, in Sweden. In 1805 Klapproth received some specimens of this mineral, which he declared to be a newmineral. Subsequently Gadolin, professor of chemistry at Abo, analyzed the same mineral, and determined the presence of an unknown earth resembling alumina and lime. He named the mineral ytterbite, and afterwards gadolinite. Klapproth has alsothe merit of having detected (1804) another rare earth, which he named ochroit-earth, found in the Bastnas mine, near Riddarhyttan, in Wcstmannland, Sweden. Curiously enough, Hisinger and Berzelius simultaneously ascertained the existence of the same...

Jan 1, 1909

Single particle breakage tests have been used by a number of researchers to investigate some salient features of the complex comminution process. The characteristics of the common single particle breakage tests such as single impact, double impact and slow compression tests are examined and the results from these tests are compared. A comparison of the results from single particle breakage tests with grindability and ball mill tests is given. Application of the results from single particle breakage tests to modelling industrial comminution processes is described. The necessity for further research into single particle breakage tests to develop a simple but comprehensive technique for estimating the breakage characteristics of ores is discussed.

Jan 1, 1986

Coal has become an enormously important export industry. Owing to a range of mainly natural advantages, Australia has been able to almost treble its exports in a little over the last decade. Australia is now the world's second largest exporter and coal is now the nation's largest single export earner.Despite this very significant growth, Australia's competitive position is in jeopardy.

Jan 1, 1984

By Fennell B

A process for the recovery of cobalt from a speiss produced at Sulphide Corporation is presented. The speiss is leached in oxygenated sulphuric acid to dissolve the metallic iron at a pH of around 4. The resultant iron (11) is subsequently oxidized in the leaching vessel and precipitates as goethite. Acid is regenerated in the precipitation allowing dissolution of further speiss. Subsequent to the conversion of most of the iron in the speiss to goethite, conditions become sufficiently oxidizing to dissolve cobalt. Cobalt is not co-precipitated under the leaching conditions, yielding a pregnant solution containing the cobalt and some iron (11). The principal advantage of such a process is the significantly lower acid consumption over that obtained by complete dissolution followed by selective precipitation. An impure product of cobalt hydroxide can be obtained from the pregnant solution by neutralization.

Jan 1, 1983

By J L. Mauk

 Broken Hills is an adularia-sericite epithermal Au-Ag deposit, hosted in flow-banded rhyolites and overlying rhyolitic pyroclastic rocks in the eastern Hauraki Goldfield. The 7.1 Ma deposit was the largest producer of gold in the eastern Hauraki Goldfield, and was one of very few economic deposits hosted in Pliocene rhyolites. This paper presents the results of a recent study in the upper levels of the deposit. Maps and cross-sections constrain structural and lithological relationships, and the lateral and vertical extent of a breccia pipe û the major feature of the upper levels.   Previous studies in the upper levels of Broken Hills have shown that gold and silver values are concentrated around and within a large breccia pipe, mined by a series of æcaveÆ stopes and in veins. Contour diagrams of Au-Ag data from channel samples indicate that the breccia pipe was a major fluid channel-way for mineralising solutions.   The breccia pipe deposits are part of the dynamic geothermal system that formed the Broken Hills ore bodies; they developed as a result of hydrothermal brecciation in areas of structural weakness within a rhyolite pyroclastic unit that overlies a massive rhyolite lava-flow unit. The main breccia pipe begins near the rhyolite/pyroclastic contact, having the shape of an inverted, inclined cone, and consists of silicified breccia, stringers of quartz, and irregular patches of clay-altered country rock. Smaller zones or pockets of hydrothermal eruption breccia are silicified and contain low grade gold in the matrix and in the adjacent silicified wall rocks.   Quartz has been classified according to its physical characteristics as seen in situ and hand specimens indicate that vein definition decreases upwards, perhaps as a result of changing lithological conditions and/or increasing proximity to the paleosurface. Hydrothermal quartz is widespread as veins and as a replacement mineral, or lining fractures and cavities and overgrowing rock fragments. Breccias contain vein quartz, but some quartz veins cross-cut breccias, indicating that vein and breccia formation was relatively synchronous and overlapped in time.   Disseminated gold-silver mineralisation is associated with vein quartz and silicic alteration of the wall rock within the breccia pipe. The auriferous zones are highly irregular and erratic, and sampling results show a wide range of gold-silver ratios, suggesting that highly volatile physiochemical conditions prevailed during mineralisation.

Jan 1, 2005

By P Duplancic and C R Lilley, R Hudson, D Beck

For deep block and panel caving mines, undercut or extraction level instability can have as much impact on overall recovery as underbreak or the premature ingress of waste. If the area of the mine affected by excessive convergence is small, recovery is usually possible. However, there are several examples of entire blocks that were abandoned prematurely due to footprint collapse. Clearly, such global instability has a major impact on recovery and must be avoided – this is one of the essential tasks for the design team.The design problem is complex. The planning engineer must ensure that the footprint has sufficient capacity to withstand the maturing loads in the cave, accounting for the effects of stress path, geological structures and the rock mass conditions. These are often uncertain and only sometimes quantified.The demand on the footprint will also be influenced by decisions and actions taken during production, especially related to draw, which can worsen a developing problem. Perhaps most importantly, the design decisions that favour stability and lead to lower deformation also negatively impact on idealised cave flow. Many engineers aim to minimise the size of extraction level pillars, to improve theoretical future resource recovery but in fact this can reduce recovery if widespread deformation ensues due to the undersized pillars.In 2014, PT Freeport Indonesia undertook detailed numerical analysis to quantify the effects of variability in rock mass conditions and geological structure on overall footprint performance. The analysis accounted for a range of stress paths and maturing cave loading scenarios sourced from a calibrated whole-of-cave deformation-flow model. The intent was to replicate some of the diversity and distribution of pillar deformation outcomes that may be seen in practice at Freeport.The discontinuum finite element analysis was able to replicate damage localisation around persistent structures, a realistic distribution of drive deformation and show how small areas of instability can evolve into major problems if poorly managed. The limits of pillar size and ground support as solutions to a number of different instability problems was also investigated, showing that pillar size alone was not a sufficient remedy for all adverse circumstances.In this paper, we describe the workflow for numerical analysis of footprint deformation. We discuss the compromises and considerations for balancing the sometimes competing needs for efficient extraction levels pillars, ground support and prudent draw strategy.CITATION:Beck, D, Hudson, R, Wilson, A D, Duplancic, P and Lilley, C R, 2016. An investigation of factors affecting the long-term reliability of extraction level pillars in deep block and panel caves, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 295–304 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By P R. Denize, V S. Wein

A brief review of the Waipipi Iron Sands Limited company history and operations over the past ten years is made along with a summary of the benefits of this mining company to New Zealand. Land rehabilitation procedures in coastal dune lands are described in detail and brief mention is made of a study of animal health and copper uptake. The paper concludes with a summary of the increased emphasis on agronomy and restoration as the mining operation commences dredging in a better class of grazing land.

Jan 1, 1981

A simple process for making filter aids from coal by controlled carbonization at 800-1200·C is described.Several possible variations in reactor design have been used experimentally, involving fluidized beds of carbon or inert material, reaction of the particles while entrained in air, and a combination of entrainment and fluidization.Product yields depend upon the composition of the parent coal but are always less than the sum of the ash and fixed carbon values determined by the proximate analysis. The product yield also depends on the air-to-coal ratio, which affects the amount of coal substance burned and the temperature attained. Particle residence time and reactor temperature affect the degree of devolatilization of the product and hence its wettability. The filtration behaviour of carbonaceous filter aids is greatly influenced by the size distribution, shape and physical properties of the particles-parameters which are largely determined by fue type and particle sizing of the coal used.Carbonaceous filter aids are distinctly different from other types commonly used and extensive industrial applications are anticipated in a wide range of industries ranging from food to mineral processing.

Jan 1, 1970

Valuable Components Recovery from Lead-Zinc Metallurgical Slag

Sep 13, 2010

By Browner R, Lincoln F. J

The activity of silver in solid gold-silver alloys (electrum) has been measured with an electrochemical concentration cell based on the super ionic conductor silver-i3-alumina in the temperature range 200 to 80oaC.The measurements of the silver activity in the range 0.5 to 90.0 atom per eent silver were found to be highly reproducible although there is some disagreement with an earlier study which used a similar technique. At temperatures above 400° the silver activity exhibits both positive and negative deviations from ideality in the silver rich region.This method suggests a simple technique for the nondestructive determination of silver in electrum alloys.

Jan 1, 1983

Large GDP increases in the Pacific Rim countries have been accompanied by similarly large increases in demand for oil products. In the case of residual fuels, this demand has been tempered by the substitution of other energy products such as coal or gas. In the region's developing and newly industrialised nations, it has not been possible to make the very large investments in infrastructure which allow other energy sources to be used for transportation. As a result, GDP growth has been mirrored in the demand growth for automotive fuels. Other non-substitutable products such as lubricants have also benefitted by the region's GDP growth.   The combination of a number of years of sustained growth, coupled with increasing quality requirements is now stretching the upgrading capacity of the region's refineries. IT, as seems likely, the region continues to enjoy a high GDP growth rate, then this will be accompanied by increasing reliance on finished products coming out of the Middle East.   The owners of the most simple form of refinery in which crude is simply distilled and the naphtha reformed into petrol will face major capital investments. If they decide not to bear this cost, they will face increasing problems in selling their surplus residual fuel oil at an economic price. Quality will become an increasingly important issue. Not only in the well publicised areas such as unleaded petrol, but also for products such as lubricants which play a major role in the efficiency of modem equipment. Quality of service such as hours of opening, ease of access, and service station facilities will also become increasingly important as the oil companies use these to attract customers and gain brand differentiation.

Jan 1, 1990

At Appin colliery, geological structural analyses and investigations of roof conditions suggest roof failure may be attributed to vectorial stresses acting on underground openings, and inducing movement along inherent discontinuities in the surrounding rocks. Certain complex joint and fracture patterns tend to exhibit the effect of this movement resulting often in local deterioration in natural support.The following conclusions are drawn.1. Roof failure is related to the inherent nature of the roof rocks, the presence of mechanical discontinuities, and the vectorial stresses imposed upon it.2. Roof failure is not necessarily related to the statistically most prominent jointing.3. Colliery development approximately parallel to the direction of the statistically most prominent jointing sometimes results in favourable roof conditions.4. The maximum principal stress is the resultant of those vectorial stresses acting upon a mine opening and may be inferred from roof adjustments to those stresses after mining.5. Statistical analyses of jointing in the mine workings can provide clues to the tectonic force or forces which have been regionally or locally influential.6. There is a probable relationship between mining induced fracturing, jointing, and micro-fractures in quartz grains, within the sediments of the mine roof.

Jan 1, 1970

Mining One (M1) is often challenged with the task of evaluating deposits considering open cut and/or underground (UG) mining methods. In many near surface deposits a combination of both methods results in the optimum economic means of exploitation. As common as it is to have open pit mines eventually develop into underground mines, theory associated with determining the optimum underground/open pit interface location continues to be subject to refinement. With recent developments in underground software packages, the generation of rudimentary underground mining stopes from basic economic inputs is not only fast, it provides a practical underground mining solution. The determination of the open pit/underground interface is not new to Gemcom's Whittle 4X (Whittle). However, its solution has only ever claimed to be indicative, mainly due the rudimentary nature of how Whittle represents any potential underground mining. The efficient generation of the aforementioned underground mining solution has provided mining engineers with a unique opportunity. Underground mining can now be represented within the Whittle environment to allow the open pit/underground mining scenario to be modelled with increased accuracy. Providing Whittle with the ability to now consider mineable underground stopes combined with the consideration of time value of money (discounting), has delivered a solution with higher credibility than ever before.This paper will elaborate on the potential value gains associated with improved accuracies in the modelling of any potential underground mining in the Whittle environment. Furthermore, it will explain the importance of incorporating time value of money in the optimisation process to provide a consistent solution through to pit selection and final analysis.

Dec 6, 2010

The mineralogy, textures, and genetic significance of a silver-rich siderite vein and an apparently co-genetic galena vein from the South mine, Broken Hill are discussed.Both veins cut sharply across the Main Lode Horizon and appear to be coeval with thc A.B.H. Consols lode.The minerals of thc siderite vein apparently result from the preferential leaching of silver from Main Lode Horizon ore with a demonstrable "breakdown series" commencing with tetrahedrite, passing through silver sulpho-salts, and ending with simple binary compounds or with elemental silver.The siderite vein has been deposited by metahydrothermal fluids along the lines of Schneiderhohn's "secondary hydrothermal" mineralization.

Jan 1, 1968