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By Taylor GP

Mining Lease SML 57 was registered to Mount Kasi on 5 January, 1995. The Mount Kasi gold mine is located in Vanua Levu, Fiji's second largest island and operated from 1932 to 1946 producing 261,000t of ore at an average grade of 7.5g/t Au. The deposit represents a structurally controlled style of high sulphidation copper gold mineralisation with peripheral low sulphidation mesothermal vein type gold mineralisation. The resource consists of 1,048,000 tonnes of residual soils (eluvium) containing 1.9 g/t Au at 0.5 g/t Au cut off and 1,240,000 tonnes of hard rock at 3.0 g/t Au and 1.0 g/t Au cut. 94 drill holes, 298 auger holes and 85 pits were modelled to outline the resource. 29% of the pits bottomed in mineralisation and it is likely the full thickness of eluvium has been understated. The pit is scheduled to produce 500,000 tonnes of ore per annum to yield 35,000 ounces of gold with an initial 2 years of eluvial ore followed by a further 2 years of hard rock ore. Total capital costs are estimated to be less than 10.0 million dollars with construction planned to commence in 1995. The likelihood of locating further ore is high.

Jan 1, 1995

By J Stojanovic, V Kasic

Gold-bearing polymetallic sulfide deposits are common in Serbia, and mostly occur in the Karpato-Balkan and, to a lesser extent, the Serbo-Macedonian metallogenic province. These deposits û Coka Marin (Majdanpek), Grabova Reka (Blagojev Kamen), Lece (Medvedja) and Veliki Cip (Boranja) û are dominated by Cu and/or Pb-Zn mineralisation that contains a variety of Pb, Zn, Cu and Fe (¦ Sb, As, Bi) sulfides and sulfosalts, as well as native elements. Gangue minerals are composed of quartz, carbonates and rare silicates and barite. Based on their gold content these deposits can be divided in three groups:1. Polymetallic deposits with a high gold content (>1 g/t).2. Polymetallic deposits with an intermediate gold content (0.1 to 1 g/t), and3. Polymetallic deposits with a low gold content (<0.1 g/t). Gold occurs as native gold or as an alloy with silver. Native gold ranges in size from 5 to 20 ¦m, with a few rare grains over 100 ¦m, as isolated grains or as microveins (in the first group of deposits). Its distribution within the deposit in uneven. Native gold in the second group is smaller in size (1 - 5 ¦m, rarely 20 ¦m), where it is uniformly distributed in a quartz-silicate matrix. The third group is of no economical importance. The subject of research has been the first group of polymetallic deposits.

Jan 1, 2008

By O Kirtel, A A. Faizan

With the rapid increase and development of high-speed trains (HSTs), the problems such as train-induced ground vibration and its dynamic effects on nearby structures have become a major environmental concern in urban areas. Ground-born vibrations produced by high-speed trains pose a great challenge for engineers to build structures in such areas that is applicable for residents. In order to study the effect of train-induced ground vibration on nearby buildings, an advanced three-dimensional finite element model for train-induced ground vibrations has been developed using PLAXIS 3D Ultimate. The results of the in situ measurements which was previously carried out by the authors were used to validate the numerical model. The field test for ground vibration due to the passage of a high-speed train was carried out on the Istanbul-Ankara high-speed railway in Turkey with a train speed of 250 km/h. An in-depth analysis was achieved to investigate the effect of different soil properties on the train-induced ground vibrations by using the verified model. According to the result of the vibration analysis, the relative vibration response curves in all directions (x, y, z) for different soil conditions were obtained comparatively. The obtained results of the vibration analysis are discussed in order to figure out some useful conclusions.

Nov 29, 2022

Current problems in predicting sub-surface strata movement and fracture development due to longwall mining have highlighted the need for more accurate, dependable methods of physical modelling of rock mechanics problems which are beyond the capabilities of current mathematical techniques. Physical model studies of the caved zone above the working faces up to the base of a water source are of importance in attempting to understand changes in mass permeability due to induced fracture zones and the resulting ground water conditions. Turkey's most important supplies of coking coals are to be found within the hard coal resources of the Black Sea coast. Coal seams up to 9 metres thick, dipping at angles as steep as 90 degrees are being successfully mined at the Kozlu Mine. Since 1956, mining operations have been carried out under the sea in dry conditions. The undersea mining conditions of the Kozlu Mine have been investigated using scaled physical models constructed from artificial materials which satisfied necessary scaling requirements. Models representing the in-situ conditions were tested and the following extraction sequence was employed: 1. The Sulu Seam extraction 2. The Acilik Seam extraction (as two slices) 3. The Piric Seam extraction. The displacement of the fixed reference points were subsequently measured using a high precision photogrammetric technique and induced horizontal and vertical strains were calculated.

Jan 1, 1988

IN the present paper it is the writer's intention to largely confine the subject-matter to details relating to the metallurgical practice in connection W,ith the blast roasting of lead ores at the Port PiJ;ie works of the Broken Hill Associated Smelters Pty. Ltd. rather than to elaborate on mechanical plant details which are more or less standard equipment of the average Dwight and Lloyd or Huntington-Heberlein blast roasting installations (hereinafter referred to in the text as D. & L. and I.I. & H. respectively). The present blast roasting plant is a combination ot D. & L. straight line machines and IQ-ton H. & H. pots. The latter installation was an operating unit prior to the introduction of the D. & L. machines, the pre-roasting then being accomplished in Ropp roasting furnaces.On the introduction of the D. & L. machines the use of the Ropp roasting furnaces as a pre-roasting unit was discontinued, and this step of the process was then carried out on one section of the D. & L. installation.Consequently, then, the present plant consists of (1) A section of D. & L. machines, which operate solely as a pre-roastiIig unit. (2) A section of D. & L. machines which operate to their full capacity as 3, final roasting unit and treat the main portion of the pre-roasted material.

Jan 1, 1922

By J R. Kyle

The Deep Mill Level Zone (DMLZ) skarn Cu-Au deposit is the deepest explored part of the Ertsberg East Skarn System extending from the surface at 4200 m elevation to the DMLZ at 2900 to 2600 m. The DMLZ is hosted in an upper Cretaceous to lower Tertiary siliciclastic and carbonate succession adjacent to the 3 Ma Ertsberg pluton. Much of the DMLZ ore is hosted by mixed assemblages of siliciclastic and dolomitised carbonate strata that have been altered to Mg-rich skarn assemblages. Unaltered equivalent strata from a 300 m cored interval in the Yellow Valley Syncline were characterised petrographically and representative samples were analysed for major element compositions. These stratigraphic and chemical units are interpreted to be responsible for the varying skarn lithologies within the DMLZ. The dominant prograde skarn assemblages are controlled by protolith composition, notably the relative abundance of quartz, dolomite, and calcite within the protolith. Models based on isochemical metamorphism of mixed assemblages of quartz and dolomite suggest that the formation of the forsterite-diopside dominant skarn assemblages resulted in the greatest amount of pore space increase. DMLZ Cu-Au concentrations were locally controlled by host lithology, with structural features providing fluid pathways that focused the mineralising fluids. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

THE power requirements of the Mount Lyell Mining and Railway Company at Queenstown, Tasmania, have, since the inception of smelting operations in June, 1,,896, been derived continuously from the extensive forests in the watershed of the Queen River, adjacent to -the works, the firewood being of good quality, mainly composed of myrtle or beech (Fagus Ounninghami), eucalypts, and manuka (Leptospermum ericoides).The country is very rugged and mountainous, indented by numerous ravines and gullies, and intersected by many creeks, which are subject to periodical floods, under the influence of a heavy and persistent rainfall. The areas so far exploited aggregate a total of about 42 sq. 'miles, and this denuded country gives promise of ultimately becoming very valuable pastoral ground for cattle-raising. The tonnage of wood yielded per acre varies from 40 to 100 tons on stack measurement of 80 cub. ft. per ton, 60 tons per acre being considered a good average yield. The gross amount of firewood handled during the past 13 years approximates 1,200,000 tons, the greater portion of which has been obtained by ordinary tramming methods. The company's main line of railway, 3-ft. 6-in. gauge, has served as a trunk line for all supplies derived from the Queen River valley, south of the reduction works, while the northern and western areas have been exploited by means of...

Jan 1, 1911

By Regan R

Appin Colliery mines the Bulli Seam with a gas composition of 98.5% methane and 1.5% carbon dioxide. Relaxation of the strata generally occurs to below the base of the Wongawilli Seam, some 40 m below the Bulli Seam, and approxim- ately 125 m above the Bulli Seam, for longwall face widths of 135 m or more. Previous exper- ience showed that when longwall faces were mined for a distance approximately equal to the face width, the mine ventilation could not provide sufficient dilution due to methane emissions from the underlying measures. Postdraining downholes were drilled to intersect the Wongawilli Seam below the operat- ng longwall. These holes were connected to an underground to surface gas range and various suction levels were applied to improve gas drainage. The resulting gas flow rates and purity from all the downholes were regularly monitored and peak flows in some holes exceeded 160 1/sec. The surface plant drained almost 20 million m3 of gas for the period July 1981 to January 1982 at an average methane purity of approximately 70%. Distinct patterns emerged for different downholes from curves illustrat- ing their variations in flow rate with distance subsequent to passage of the longwall face. The difference between free flow characteristics and those obtained with the application of

Jan 1, 1982

The Olympic Dam deposit is located some 600 km north of Adelaide in South Australia. It was discovered in 1975 by Western Mining Corporation and in 1979 a joint venture was formed with British Petroleum for the evaluation and development of the project. Studies were completed and construction started in 1986 with the plant being commissioned progressively between April and August of 1988. In 1993 Western Mining acquired BP's interest and are now owners of the whole deposit. The scale of the initial development was 1.5 Mtpa of ore for the production of 45 000 tpa of copper cathode, 900 tpa of uranium oxide and some gold and silver. Two expansion programs have occurred in 1992 and 1995 and current performance is at the rate of 3 Mtpa of ore for the production of 84 000 tpa of copper cathode, 1500 tpa of uranium oxide, 24 000 oz per year of confined gold and 380 000 oz per year of confined silver (Table 1). An aerial view of the plant is shown in Figure 1. The benefit of diversifying into the production of more than one product is undoubted and the flexibility of being able to produce variable quantities of copper and uranium also allows advantage to be taken of a change in market conditions.

Jan 1, 1996

By W A. Take, M McKellar, A Walsh, S McDougall, S G. Evans

Recent tailings dam failures have heightened public awareness of the hazard posed by storage facilities for mining waste, illustrating the need for a more critical examination of tailings dam breach mechanisms and the potential mobility of liquefied tailings. Knowledge from tailings dam breach studies will help improve safety and risk management through more accurate inundation maps, dam consequence classifications and emergency preparedness plans. Tailings dams differ from conventional water retaining dams, although dam breach relationships used in practice rely heavily on relationships derived for breach processes from the latter. Physical modelling offers a controlled environment to advance the understanding of tailings dam breach processes, thereby allowing for modelling of simple geometry and boundary conditions to test hypotheses. The performed experiments investigate prototypical tailings dam configurations and material behaviour, with the objective of validating numerical models that will enable practitioners to better assess and mitigate tailings flows resulting from tailings dam failures. Research conducted in the Queen’s University Landslide Flume at the Coastal Engineering Laboratory has investigated the breaching of 1 m high dams with tailings geometry by overtopping initiated by a v-notch incised in the dam crest. This paper presents the initial results of the next stage of this research comparing the outflow hydrograph following loss of containment caused by shear failure to overtopping initiated by notch flow. The two dam experiments presented are constructed with similar dam and reservoir geometries allowing for a direct comparison of the effect on the outflow hydrograph of each failure event. Preliminary outcomes suggest that although both dam failure events are triggered from separate mechanisms their geometries allow for similar values of Q_peak to be reached. Future work is currently planned to expand the shear test series to explore the influence of failure mechanism on the outflow hydrograph.

Jul 1, 2021

A laminar-flow furnace technique was used to study the combustion of 37-53 µm size fraction of Woodlawn copper concentrate containing 7.4 per cent zinc, 5.0 per cent lead and 22.5 per cent copper. Factors studied included the effect of time, temperature and the distribution of volatile elements between the panicles and the fume. Air was used for most of the work but a few tests were carried out using 1 per cent oxygen in nitrogen. Chemical analysis, X-ray diffraction, and scanning electron and optical microscopy of polished sections were used to characterize the reaction products.When the concentrate was combusted at low temperatures (800-900°C), the fume was rich in lead. At higher temperatures, this was diluled by increasing amounts of zinc and copper. 70 per cent of the zinc, 60 per cent of the lead and 40 per cent of the copper were found in the fume after oxidation at 1400°C. Lead, zinc and copper were present in the fume as anglesite (PbSO4), zincite (ZnO) and cuprite (Cu2O) respectively. The major phases present in the panicles were magnetite (Fe3O4) and/or cuprospinel (CuFe2O4), with some zincite and cuprite.Elemental copper was found in the particles oxidized in 1 per cent oxygen. Possible vapour species responsible for the vaporization are discussed.

Jan 1, 1985

By M McDonald

KiwiRail has a goal of significantly improving passenger rail services to west Auckland, as part of its DART (Developing Auckland’s Rail Transport) suite of projects. The New Lynn Rail Trench (NLRT) project was a significant component of this work. The NLRT project facilitates essential doubletracking of the Western Auckland line, and provides a new commuter transportation hub within a busy town centre.The 1.5 km stretch of track through the New Lynn town centre has bisected the township for over 80 years. Double-tracking the line provided the opportunity to grade-separate road and rail, which would help to re-connect both sides of the township and enhance public amenity and safety.KiwiRail employed an Early Contractor Involvement (ECI) procurement model engaging a consortium comprising Fletcher Construction, Beca Infrastructure and Synergine to develop a Design and Construct solution.With weak soil conditions and high groundwater levels, a diaphragm wall construction method to form the trench walls was selected as the best solution. Further challenges to construction included working within a narrow rail corridor constrained by buildings along much of the boundary, and a requirement to keep the existing line open for rail services. Detailed construction planning was required to ensure rail and construction safety in a constrained space whilst building the trench walls, propping these walls during excavation, and constructing the base slab in the most efficient way possible.This paper will detail the geotechnical conditions and the additional constraints that made this rail trench a challenging structure to design. It will also describe the fi nal design and construction methodologies that were employed, that allowed very successful completion of the project.Additionally, this paper will review the design and construction lessons applicable to the current Victoria Park Tunnel project, and indeed for all future cut and cover tunnel projects in the Auckland isthmus.

Mar 8, 2011

By P N. Martens

In the course of the development of the Report of the World Commission on Environment and Development (WCED) in the 1980s an expression was introduced in the public discussion on environment and development that influenced the international and national policies of the last 20 years in all areas: sustainable development. The UN decided in 1992 to implement a program with the Agenda 21 which contains the demand for developing indicators for sustainable development. In this context an indicator is understood as a quantitative or qualitative measure that can be measured or described throughout time and which moreover is able to depict the current status and changes. In order to enable for a simple holistic assessment of sustainable development, highly aggregated indicators are required, which integrate the criteria identified as relevant within a framework to be defined. In the presented paper, sustainability indicators for the mining industry are developed that account for the allowances of the sustainable development concept and the Agenda 21. The indicators are quantifiable and traceable through time so that developments can be traced and assessed. Furthermore, the indicators account for the multidimensional aspect of sustainable development. They are designed to allow for the integration of several dimensions in one indicator. The premises that are underlying the development of the indicators are the minimisation of negative impacts on the environment and society while simultaneously considering the maximisation of social and economic factors. Moreover, the participative momentum that is part of the sustainability idea is safeguarded in explicitly integrating the social acceptance of certain measures into the assessment. The indicators presented are based on the logical combination of statements through the use of Boolean algebra. Starting with basic statements for which the logical value is oriented on the sustainability paradigm, complex multidimensional statements can be constructed and assessed.  

Jan 1, 2009

The first thing to be aware of is that the warming effect of carbon dioxide is strongly logarithmic. Of the 3¦ that carbon dioxide contributes to the greenhouse effect, the first 20 ppm has a greater effect than the following 400 ppm. By the time we get to the current level of 384 ppm, each 100 ppm increment will produce only about 0.1¦ of warming. With atmospheric carbon dioxide rising at about 2 ppm per annum, temperature will rise at 0.1¦ every 50 years for the next couple of hundred years before the effect becomes minuscule. The warming of the 20th century, as the Earth came out of the Little Ice Age, was a consequence of short, high-amplitude solar cycles. A number of solar physicists have predicted that the next solar cycle, Solar Cycle 24, will be quite weak. Based on the correlation between solar activity and the EarthÆs climate, a temperature decline of 2¦C is predicted for the mid-latitude regions over the coming decade, equating to the experience of the Dalton Minimum. Anthropogenic warming due to carbon dioxide will not ameliorate this temperature decline. Increased atmospheric carbon dioxide is wholly beneficial due to itÆs fertilisation effect. Efforts to inhibit Australian carbon dioxide emissions are exactly wrong in science.

Jan 1, 2009

By P Revell, A Jenkin

This paper presents an analysis of significant Australian-based R&D programs focussed on the minerals industry, which was commissioned by CRC ORE. The landscape analysis may assist organisations with R&D management issues including program creation, program/partner selection, portfolio management, and public policy settings. The dataset was collated early in 2020, and contains programs being conducted by or with Australian-based ‘Research Service Providers’ (RSPs), most notably Universities and CSIRO. It does not include R&D being conducted in-house by mining and METS companies, or by them with other organisations that are not RSP’s. The dataset contains 65 R&D programs, with total annual cash funding of $229m (70% from industry and 30% from government). The total funding compares unfavourably with the combined R&D expenditure of Australian universities and CSIRO of over $12b, and minerals industry export revenues of over $200b. The R&D landscape is analysed by program numbers and funding, technical domain, geography, and funding source. Areas of relative strength are noted in ‘mineral processing’, CSIRO Minerals, and the CRC program. Areas of relative weakness are noted in ‘bulk materials handling and logistics’, ‘tailings and waste management’, and ‘social and community’. The field of preconcentration is noted as a current area of R&D strength, but it is under significant threat with the impending completion of CRC ORE. The overall R&D landscape is characterised by a majority of small-scale programs, low levels of industry coordination, a low focus on step-change innovation, and total funding lower than should be expected for such a large critical industry. It is hoped that key stakeholders in the Australian minerals industry, particularly governments, and mining and METS companies, reflect on the analysis and act to address holistic weaknesses.

Nov 10, 2020

By S Brochot

In cases where coarse gold is present in a deposit, it is usual to use the screen fire assay (SFA) method to analyse the samples. There is no doubt that this method is more accurate than the standard fire assay (FA) and reduces the risk to have a systematic bias. Nevertheless, the difference between the analytical errors of both methods can be glossed over when the overall sampling error is added to obtain the measurement error. In that case, the advantage of the SFA cannot justify its higher cost.The current paper attempts to address this question in the case of a gold ore deposit with visible coarse gold in various sampling situations (drill core sampling in exploration, blasthole or chip sampling in mining exploitation). The overall measurement error is estimated taking into account the analytical error and all the sampling error components following the Pierre GyÆs theory of sampling.Firstly, only the last sampling stage is considered when the pulverised sample is processed either to obtain one analysis sample for a FA or to be screened and subsampled for a SFA. The calculated measurement error clearly shows the advantage of the SFA specifically in presence of coarse gold. Secondly, the half core sampling is studied to explain the observed discrepancies when controlling the second half core. Finally, the blasthole sampling is treated using in situ heterogeneity models to show that the relative advantage of the SFA is hidden by the large overall sampling error.In conclusion, the choice of the assaying method is discussed at the light of the overall measurement error and in accordance to the analysis objective.CITATION:Brochot, S, 2012. Standard fire assay or screen fire assay? Application of the overall measurement error approach to choose the most appropriate method, in Proceedings Sampling 2012 , pp 135-142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

Early efforts to control the dust necessarily produced during dry crushing operations, took the form of venturis at loading chutes and other places where dust was most evident. These venturis discharged to the atmosphere and for obvious reasons were not very satisfactory.Attempts to collect the dust drawn off by the venturis, using dry cyclones, were not successful, the cyclones catching only the coarser particles. Further, no satisfactory method of continuously discharging the dust catchment was evolved. Water sprays were also used, and will be referred to later.In 1940, a single discharge fan of 3,000-4,000 cu. ft. per minute capacity, was installed to draw the dust-laden air from the Symons crushers and ·screening sections with their attendant conveyors. Suction was through two 15 in. ducts which branched off into 10 off-takes situated over the conveyers at points of discharge from crushers and screens.A dry cyclone was installed in front of the fan, which exhausted into a bag-house.The cyclone suffered from the defects of the smaller units mentioned earlier. When the collected dust reached a certain level in the cone, no more collection would take place until the cone was emptied. This objectionable feature was overcome by introducing a jet of water ahead of the cyclone. The water and dust collected overflowed a weir and were pumped to the mill.

Jan 1, 1948

Characterising the weight percentage of each mineral in base metal ores is an integral part of assessing the quality of an ore in terms of its processing properties. The Rietveld method, which uses X-ray diffraction data, has been applied to routinely quantify the minerals in lead/zinc and copper ores from Mount Isa Mines Limited and supergene copper ores from Ernest Henry Mining as well as their related products from the concentrators. The Rietveld method has been tested by comparing Rietveld mineral data with a standard sample with known mineral weight percentages and comparing Rietveld mineral data with mineral data calculated from elemental assays where the element only exists in one mineral such as lead in galena. Where this latter situation does not occur, the Rietveld method has been checked with both elemental and optical microscope data. In all cases, there is a good correspondence between the Rietveld data and the data it was checked against with absolute differences generally in the range of 0.5 to 3 wt per cent. The Rietveld method generally quantifies all minerals occurring over 1 wt per cent in one analysis and is less expensive and more routine compared to traditional methods such as optical microscope point counting. The Rietveld method can be applied to many stages of the mining cycle such as exploration, feasibility studies, mining, minerals processing and for environmental studies.

Jan 1, 1998

At the beginning of this year it was my pleasure and responsibility to take over the Presidency of our Institute from Mr A. A. Parish who, as did his predecessors, filled the office with distinction. It is a great privilege to address you as President and it is an occasion for my wife and family, and I am most grateful for your inviting them to the buffet dinner. Our Secretary (Miss Jacka), who processes all Presidents, has told me that there are neither questions nor discussions on Presidential Addresses, and that being so, I felt free to select a controversial topic. The address I have prepared is not strictly true to label; because I intend to include also the effect on agricultural production in Australia if Britain joins the European Economic Community (i.e. the Common Market).Three points of view are1. the European, which is one of equanimity deriving from the initial brilliant success of their scheme,2. the British, which is one of anxiety not to miss the bus, coupled with a commendable wish not to inimically affect existing Commonwealth arrangements,and3. the Australian, which is one of alarm.In England all are drawing their own conclusions on the subject and views range from the extreme desirability, to the extreme undesirability, of the United Kingdom joining.No one in Britain wants Australia, or New Zealand, to...

Jan 1, 1962

Titanium dioxide (TiG ) is produced 2 commercially by two methods generally referred to as the "sulfate" route and the "chloride" route. The SCM Corporation, in supplying 15% of the world's demand for TiO 2, uses both of these processes. Of the two processes the sulfate route is generally regarded as the older and more established technology. Worldwide the sulfate route accounts for some 70% of total Ti02 production. However, in the U.S.A. the chloride process accounts for 80% of production. The processes vary in chemistry and raw material requirements. In the "sulfate" process finely ground ilmenite or titanium slag is digested with sulfuric acid to produce a porous "cake" vrnich is extracted with water and recovered liquor. The solution is treated with scrap iron to reduce any ferric ions to the ferrous state which is then crystallised and removed as ferrous sulfate heptahydrate. The liquor is concentrated by evaporation and hydrolysed to form the insoluble hydroxide which is filtered and washed free of impurities. This is converted to the dioxide by calcination at 800 - 1000¦C and milled to break up any aggregates. The "chloride" process uses a higher quality feedstock of natural or synthetic rutile and/or high grade titania slag. The feedstock is mixed with ground high-purity coke and chlorinated at 950¦C in a fluidised bed. The resulting crude titanium tetrachloride is purified by distillation and chemical treatment. The purified titanium tetrachloride is burned with oxygen or oxygen enriched air to give titanium dioxide and chlorine, which is recovered and recycled to chlorination. Titanium dioxide pigment from both processing routes undergoes similar finishing techniques. It is subjected to further stages of wet and dry milling, then coated with layers of inorganic oxides in order to enhance its properties for specialist applications.

Jan 1, 1986