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Mineralisation adjacent to Herberton occurs within three main subcentres. The Her- berton Hill subcentre is characterised by the association of Sn,W the Herberton Dividing Range South subcentre by Sn, and the Herberton Dividing Range North by Cu, As. The relation- ships between the subcentres are discussed in terms of metal distribution, production, deposit types, wall rock alteration and re- lationships with granitoid intrusives. The temporal and three dimensional spatial re- lationships between the centres are uncertain.

Jan 1, 1978

Diamonds have been known in Australia for many years, especially in association with alluvial gold and tin occurrences. Exploration for primary sources in the Kimberely area of Western Australia has been carried out since 1968, culminating in the discovery, in 1979, of the Argyle Kimberlite No 1 (AK1) kimberlite pipe. Various techniques have been used in the search for diamonds such as geologic interpretation, aerial photography and Landsat, soil geochenical techniques, geophysics, and stream sediment sampling. Stream sediment sampling, a method developed in South Africa, using the detection of indicator minerals derived from kimberlites in gravel samples, has had wide application and success in Australia. Nevertheless, although Australian diamond bearing kimberlite and lamproite rocks contain some of the classic indicator minerals, their concentrations are generally much lower than in South Africa and Russia. Despite this paucity of indicators, stream sediment sampling is still the best known and most commonly used method of diamond prospecting in Australia. Small samples are treated by hand but larger samples require the use of diamond pans, jigs or heavy media separation plants. Each of these methods has advantages and disadvantages. The final concentrate is passed over a grease table or subjected to x-ray sorting.

Jan 1, 1984

The purpose of this paper is to review recent approaches by regulators, employers and employees and their associations to the introduction of flexible employment practices and the management of fatigue related risk. More importantly, it will focus on developments in our law either through legislative change and cases which have dictated trends. The paper particularly considers the limitations imposed by occupational health and safety legislation to resist or limit the move to flexible workplace practices on the basis that such practices are unsafe.

Jan 1, 2003

In Australian collieries, solutions to the outburst problem must be implemented in a highly competitive environment which has a low tolerance on negative productivity effects. Solutions are only applicable if the overall viability of the operation remains sound. Minimum time must be spent on alleviation and control measures. This is favoured by simple geology, advanced warning and efficient alleviation and control procedures. Research requirements in support of this include 1. an improved means of predicting the nature and location of outburst zones ahead of the face and, 2. an improved means of measuring the effectiveness of gas drainage. For additional safety at the face, a means of continuously monitoring outburst proneness is required. In general, greater emphasis is required on improved instrumentation.

Jan 1, 1987

By Szymanski J

In the first part of this paper, the principal sources of dilution during underground evaluation and mining are discussed, then definitions of ore dilution currently in use are analysed. These definitions vary depending on the authors. Ten different analytical expressions of dilution percentage currently exist. It is demonstrated, with the help of a numerical example for a given mining condition, that dilution percentage results vary considerably and that they depend on the definition used. This situation makes it difficult to compare different results regarding the dilution problem, often because some of the terms used are contradictory. A new ore dilution evaluation methodology is proposed, replacing the ten different analytical expressions by only two: the planned dilution factor related to the stoping selectivity, done at the mine planning level, and the additional dilution factor related to the efficiency of the dilution control measures during stoping operations. The conclusion shows that the use of this methodology would be a definitive asset in planning, in stoping operations follow-up, and in future costs comparison studies between mining operations.

Jan 1, 1995

When, in 1985, Marty McFly is accidentally sent back to 1955 in a DeLorean ‘time machine’ in Back to the Future, he encounters young versions of his parents, and must make sure they fall in love or he will cease to exist. This Conference celebrates 40 years since the inaugural Mill Operators’ Conference in Mt Isa in 1978; over this period, great technological advances have been made in almost all aspects of mill operation, resulting in considerable improvements in grades and recoveries from ever-more complex ores. However, in 2018, the mining industry is facing challenges that might have been difficult to predict in 1978 (or were they?). The computer revolution, the information revolution, and the bio-technology revolution have all contributed to the increase in operating efficiencies, but, combined with the social revolution, they also call into question the existence of the mining industry as we know it. This presentation looks back at the ‘way things were’ in the 1970s, and at what was then considered to be the ‘basics,’ and attempts to sketch what the mining industry might be like in 2058. As Back to the Future Part II demonstrates so vividly, it is much easier to review the past than predict the future. It is difficult to know what form the mining industry will have in 40 years’ time. Nevertheless, as this presentation will argue, it is important to take action now, to ensure that it (like Marty McFly) does not cease to exist. Some courses of action are proposed, including going back to the basics of a very different past.*This is an abstract only. No full paper was prepared for this abstract.*CITATION:Franzidis, J P, 2018. Back to basics or back to the future?, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 3–4 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By K Zhao, H Gong, B Li

Health and safety are the first priority for Australian minerals sector. Australia has a global reputation in the mining industry. However, accidents occur every year. Legislation and regulation are important to prevent the accident from occurring, so do the new technologies. It is sad to witness the collision incident persisting and the long called collision avoidance system (CAS) is still not widely used in underground mines. The main reason is that the existing systems are still not advanced enough. The current CASs utilise GPS, infrared, ultrasonic, RFID, Radar, electromagnetic etc have their limitations and disadvantages. For instance, GPS is widely used in a surface mine, but it cannot be applied in underground mine; Infrared and electromagnetic have the false positive problem.

Sep 1, 2024

By Baafi EY

Open cut mining in Australia is facing the greatest challenge in its history in attempting to compete not only with other operations internationally, but also with underground operations domestically. Most flat dip and shallow depth surface-mineable coal reserves have been depleted during the last two decades and new open cut operations must extract deeper coal deposits. As open cut coal mines move into deeper areas and the stripping ratios increase, the relative cost of overburden removal also increases. It therefore becomes even more important to design the mine around the optimum overburden removal scheme. The deeper mines are usually multi-seam operations with a more complex geology and with more geotechnical and hydrological problems. Deeper mines are subjected to greater problems requiring more detailed mine planning and design, such as selection of the optimum mining method and pit layout. In planning and design of such operations, the number of alternative methods which need to be considered is consequently greater.Dragline productivity and its stripping capabilities are directly affected by the selection of digging method, strip layout and pit geometry. Every mine has a unique combination of geological conditions. The operating methods that work well at one mine may not necessarily work at another site. Selection of an optimal stripping method, strip layout and pit geometry for a given dragline must be considered with respect to the geological conditions of the mine. With increasing geological complexity of Australian strip mines, it is becoming more important to use sophisticated techniques such as computerised mine planning methods to assist in optimising dragline operations.

Jan 1, 1998

In November 1992, the Internal Revenue Commission (IRC) was formed from the rperggr of the Papua New Guinea Taxation Of- fice (PNGTO) and the Bureau of Customs, and now has the re- sponsibility for the administration of direct and indirect taxes on a national basis in Papua New Guinea (PNG). Since that date we have undertaken many initiatives to make the new organisation more efficient and responsive to clients' needs. Income Tax The mining industry is catered for, in respect of income tax, un- der a separate taxation regime within the Income Tax Act (ITA), Division 10, as well as some general provisions within that Act as may be applicable. Division 10 is itself broken up into subdi- visions to cover the different types of mining leases, namely Spe- cial Mining Leases (SMLs) and Mining Leases (MLs), and peri- ods of time during which those sub-divisions apply. Ring Fencing Income tax assessed on the mining industry, with the exception of Mining Leases (these will be explained later), has a project basis of assessment, that is, each project is assessed separately as if the taxable income of the taxpayer from operations attributable to the project was the only assessable income derived by that taxpayer. This is often referred to as "ring fencing". This is an important point to consider because losses from unsuccessful projects cannot be set off against income from those that are suc- cessful, except in very limited specific circumstances, such as where an unsuccessful exploration licence is cancelled or surren- dered. The project basis of assessment applies to both resident and non-resident companies. A relaxation in the 'ring fence' provisions was applied from 1st January 1995, where ten percent of exploration expenditure, in- curred in areas outside of Special Mining Leases and Petroleum Development Licences in a particular year of income, can be claimed as an outright deduction which is limited to ten percent of the tax otherwise payable in that year. This was introduced to encourage exploration in PNG.

Jan 1, 1997

By P Radulovic, W Y. Lui

The Mount Isa Mines (MIM) copper concentrator at Mount Isa processes both chalcopyrite ore from the MIM underground mine and rotary holding furnace (RHF) slag from the MIM copper smelter. There have been numerous changes to the processing practices since commissioning this concentrator in 1973. Current management of the concentrator extends from grinding and flotation to concentrate handling (thickening and filtration) and tailings disposal (fill plants, tailings thickeners and process water systems).Predominant mill feed through the concentrator is chalcopyrite ore. RHF slag is processed when concentrator production exceeds mined ore production. The chalcopyrite circuit has two stages of grinding in parallel lines (Line 1 and Line 2). Each line has parallel preflotation and rougher banks, combining into a common scavenger/retreat circuit (including regrinding) and common cleaner circuit. RHF slag may be milled in parallel with chalcopyrite, utilising Line 2 flotation roughers and a Jameson cell cleaner. All final concentrate produced is combined and pumped to the concentrate handling plant. The concentrate is thickened, pre-fluxed and filtered in hyperbaric disc filters. Fluxing specification is set by the copper smelter, and filtered product transferred via conveyor belt to the smelter concentrate storage facility.Wet fill and paste fill plants utilise flotation final tailings as hydraulic or cemented hydraulic fill for stopes underground. Cement ratios and fill plant utilisation are varied depending on underground stope fill requirements. Tailings from the adjacent lead-zinc concentrator are also processed at wet fill. All tailings that are not utilised for backfill are pumped via wet fill to three parallel tailings thickeners. Thickener underflows are gravity fed to the tailings dams with thickener overflows recycled for site process water use. In addition to summarising historical operations, this paper will provide a detailed outline of more recent changes in the concentrator flotation circuit, equipment upgrades, reagent optimisation as well as product and process optimisation at the final concentrate handling and fill plants.CITATION:Lui, W Y and Radulovic, P, 2013. Mount Isa Mines copper concentrator - An insight into current and historical practice, in Proceedings MetPlant 2013 , pp 553-574 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By Cripps-Clark CJ, Deague TK

In order to study conditions under which SiO(g) may be formed in a blast furnace, equilibrium phase diagrams were constructed for the combustion of high and low ash cokes with oxygen-enriched blast and oil injection under conditions of high and low raceway pressures. Free energy minimisation techniques were used to calculate the composition of gaseous and condensed phases. Where coke ash is assumed, for simplicity, to comprise Si02 only, the coke can be comple- tely gasified, mainly to SiO and CO, under restricted conditions of coke to blast ratio and at temperatures greater than 1600 - 1650¦C, depending on system pressure. The formation of SiO(g) is partially suppressed by the introduction of alumina into the ash, because of the formation of solid and liquid alumino- silicate compounds. The minimum temperature for complete silicon gasification is raised to about 1700¦C. The results of the equilibrium calcula- tions are related-to actual raceway conditions. It is proposed that virtually all silicon in the coke ash is gasified such that, on condensation, it affects hot metal chemistry and slag properties and secondly, that the effects will be greater with higher ash cokes.

Jan 1, 1980

By L Whitbourn, K Yang, P C, E Ramanaidou

The potential of hyperspectral mineral mapping within a mine environment is demonstrated. Central to this capability has been the development of portable or vehicle-mounted, hyperspectral mine face-mapping systems. Data from these systems were used to detect subtle mineralogical variations and map their distribution across rock faces in a fashion that previously was not possible. In one study, the data usability was enhanced by ædrapingÆ the mineralogical determinations over a three-dimensional æmodelÆ of the rock-face. The eventual melding of the spectral mine face-mapping and three-dimensional spatial technologies will result in a new generation of mineralogical and structural information becoming available to mine geologists, engineers and metallurgists. Specific uses for spectrally-derived, mineral mapping data sets could include:ore grade mapping systems based on either direct detection of ore minerals themselves (eg iron and nickel oxides), or mineralogies that may be used as surrogates for ore-grade information (via various alteration minerals) after a suitable orientation survey; detecting mineralogies that have a deleterious effect on milling, metallurgical processing or have occupational health implications (talc, swelling clays, carbonates, asbestos, etc); selective mining and blending by collecting, processing and displaying such mineralogical images in near real-time to monitor ore grade and quality, and allow the separation of ore from waste during loading operations at the mine face; a mineral detection and mapping capability to assist in structural and geotechnical mine planning applications; and an enhanced geological detection and mapping capability for ore mineral species or alteration mineralogies that may be used to vector further mineralisation, update the existing mine ore model, or provide input to assist in the control of autonomous mining equipment. Within the Woodlawn open pit, Fe- and Mg-chlorites and phengitic- micas associated with sulfide mineralisation were detected and mapped. Subsequent studies using a second generation face-mapping system demonstrated the direct detection of ore-grade materials for iron-ore and nickel laterite mining activities. Satisfactory and meaningful results were extracted from data that were collected under a variety of challenging conditions. However, these non-ideal climatic and operational conditions would be expected under most operational situations in a mine environment. Development of a system using artificial illumination, permitting night-time (and eventually underground) operation and elimination of atmospheric absorption effects is underway.

Jan 1, 2006

Can mining promote sustainable development? What is sustainable development? Is sustainable development good for corporate sustainability? Does it work in practice? If so, is it good for business? This paper does not seek to provide definitive answers to these issues. Rather, it is presented in the interests of sharing information and contributing to the pool of collective experience. The discussion will draw on the experience of Placer Dome in Papua New Guinea (PNG). Sustainable development means development that is maintained at a steady level without exhausting natural resources or causing ecological disturbance. The term æsustainable developmentÆ is often linked to the concept of ecological equilibrium, development that is self-replenishing. While its essential meaning remains the same, in practice, and for todayÆs complex and industrial world, different people will interpret sustainable development in different ways. Given the dynamics of development and the competing social, political and economic interests, sustainable development must be seen from a much broader perspective. This is the point that this paper will attempt to make. Mining, an activity that uses non-renewable resources, can promote sustainable development. The 1987 Brundtland Report (also known as the Report of the World Commission on Environment and Development), defines sustainable development in a broader manner - as development that meets the needs of the present world without compromising the ability of future generations to meet their own needs (Elkington, 1997). This definition calls for inter-generational equity in the development and use of resources by many organisations, including multinational corporations. Corporate sustainability, on the other hand, is about developing strategies that guide a corporation to stay alive and, more importantly, to stay ahead of its competitors. It is basically about survival in a competitive social and commercial environment. In a corporate world, profitability is survival. In this context, corporate profitability, the main ingredient of corporate sustainability, is important for sustainable development. Without profits, corporations will find it difficult to practice sustainable development or indeed any development. Sustainable development can integrate mining activities with the rest of the community, add value and, in the long-term, profits to the bottom-line. Ultimately, sustainability will force corporations to adopt strategies based on a longer time scale to survive. In the mining sector, corporate sustainability depends on a close relationship with all stakeholders, particularly landowners for whom sustainable development is critically important. Increasingly, there is an acceptance of the view that success is not achieved simply through competition in price, cost and technology but, more importantly, through creating social infrastructure which support community ethics, norms and values essential for trust and partnership. Needless to say, mining companies that engage in appropriate community-based development in support of inter-generational justice recognise the true value of sustainability. This is sometimes called the æhuman sustainability approachÆ which underlines the critical significance of trust in relationships with stakeholders and continuous improvement of corporate capabilities directed towards the future (Dunphy and Griffiths, 1998). In the long-term, such development will enhance corporate public image and acceptability. In practice, both concepts can be built on the principles of economic viability, environmental quality and social justice -what, in todayÆs parlance, is increasingly becoming known as the ætriple-bottom-lineÆ approach to business (Elkington, 1997). Underpinning this approach is a process of continuing dialogue and co-operation between governments, non-government organisations (NGOs) and business.

Jan 1, 1999

By D Alexander

For nearly 100 years, the flotation plant metallurgist has often wondered what is happening æbeneath the frothÆ. To assist in unravelling this mystery, new technology has been developed as part of the Australian Mineral Industries Research Association (AMIRA) P9 project, to measure gas dispersion characteristics (such as gas hold-up, superficial gas velocity and bubble size) in industrial flotation cells. These measurements have been conducted in a large number of cells of different types and sizes by researchers from the Julius Kruttschnitt Mineral Research Centre (JKMRC) and JKTech. A large database has been developed and the contents of this database are described in this paper. Typical cell characterisation measurements show a wide spread in values, even in the same cell types and sizes performing similar duties. In conventional flotation cells, the typical gas hold-up values range from 3 - 20 per cent, bubble sizes range between 1 and 2 mm, and superficial gas velocity ranges from 1 to 2.5 cm/s. The ranges of cell characterisation measurements given in this paper will enable plant personnel to compare their operation to other similar types of operations from around Australia and the rest of the world, giving opportunities for further improvement to flotation plant operations.

Jan 1, 2005

By Borshoff J, Coles R

The Rum Jungle Uranium Province is lo cated on the western margin of the Pine Creek Geosyncline approximately 60km south of Darwin. Uranium was discovered in the Embayment area (Whites Deposit) in 1949, spurring active ex- ploration and leading to the discovery of the Rum Jungle Creek South Deposit in 1959. With the discovery of the Alligator Rivers Uranium Field, new criteria in the understanding of the controls for mineralization sparked a re- surgence of exploration activities in the Rum Jungle area. Uranerz Australia Pty. Ltd. (UAL) commenced exploration in the area in the late 1970's in joint venture and in its own right. Two domal Archaean granitic complexes, the Rum Jungle and Waterhouse Complexes, domi- nate the area. They are unconformably mantled by Lower Proterozoic sediments metamorphosed to middle to upper greenschist grade. The Lower Proterozoic sediments are unconformably over- lain by remnant blocks of Carpentarian sand- stone, generally preserved in downfaulted blocks. Over a six year period extensive geolo- gical, geochemical and geophysical programs were conducted to reinvestigate previous target areas and locate new prospective zones. Exten- sive shallow bedrock drilling showed that lo- cally the stratigraphic succession is quite variable and cannot always be divided into an ordered succession for correlation with groups and formations established by the Bureau of Mineral Resources (BMR). Deformational events resulting in intraformational recumbent folding and overthrusting also account for repetition of certain lithotypes.

Jan 1, 1984

Chlorination of organic matter by direct injection of chlorine gas or hypochlorite has been investigated metallurgically worldwide with little understanding of the basic chemistry of the passivation mechanisms in- volved. In this paper, chlorination of carbon is attributed to oxidation-reduc- tions, resulting in surface halogenation of graphitic or amorphous carbon. It is proposed that chlorine and carbon interact to form thin coatings of chioro-carbon complexes that block the adsorption of gold cyanide com- plexes, thus passivating the gold adsorption sites of carbonaceous matter. Analytical, spectrographic, microscopic and electron-optical methods have been applied to demonstrate the proposed mechanism of chlorine-carbon bonding, as well as to evaluate the advantages and limitations of chlorination in the pretreatment of refractory carbonaceous gold ores.

Jan 1, 1991

A major tool in the search for petroleum is reflection seismic mapping. The period which has seen most of the exploration in Victoria is also one which has seen major advances in this technology, from 1963 try present day. Seismic mapping can be divided into three interlinked areas - acquisition, processing, and interpretation. In acquisition the major changes have been from an explosive energy source in 1963 to gas exploders in 1968 and airguns in 1970. The number of recording channels has increased from 24 to 192, with digital recording introduced in 1966, and floating point recording in 1976.

Jan 1, 1982

Proposals designed to use stockpiles and buffer stocks to achieve price stabilization and better resource use have a long history. They are super- ficially simple to understand. The benefits seem clear. And yet I am well aware that this is not a simple subject: the more one studies it, the more complex it becomes. Worldwide interest in re- source management, while receiving fresh impetus from the OPEC actions, also has a long and chequered history. Those venturing into such ter- ritories must be forewarned of the traps and pit- falls which abound. Interest in these schemes has waxed and waned over the years with the fluctuating fortunes of the producers or consumers. As I write this paper towards the end of 1977, I am acutely aware of the low ruling prices for zinc, copper, and nickel. These sacrifice prices remind me that it is difficult, for example, for a surveyor, to be calm and rational if he is up to his neck in a swamp full of crocodiles. He might be forgiven for forgetting that the aim was to drain the swamp! I am also aware that when swamps are drained, painful and dangerous stumps sometimes stick out. Hence, in looking at the subject of stockpiles and resource management we must not set our sights too high, perhaps not initially hope for perfec- tion, if we want to secure worthwhile changes. My approach is to acknowledge a bias for the market system. We have, however, had experience (remember the 1930s) of some weaknesses in the untrammelled operation of free markets. Thus our international economic relationships over the past 20 or 30 years have been based on a desire to retain as much as possible of a liberal world trading system backed by such organizations as the GATT, IMF, and the U.N. to ensure the necessary cooperation. Some nations have seen this system work only partially in their best in- terests. GATT, for example, has been reasonably effective in liberalizing trade in many manufac- tured goods but far less so in regard to agricultural or semi-processed goods.

Jan 1, 1978

A narrow (200-300m) zone of amphibolite facies metamorphic rocks underlies the Papuan ophiolite near the Musa-Kumusi divide, SW of Popondetta, Oro Province. The amphibolite rocks are bounded up-section, to the NE, by peridotite and gabbro of the ophiolite; and down-section, to the SW, by mafic greenschist, which in turn overlies blueschist facies mafic schists of the Emo Metamorphics.Amphibole compositions within the narrow contact zone show a strong chemical zonation which reflects a steep thermal gradient, with maximum temperatures >800¦C at the peridotite contact. The zonation is recorded in Ti content and A-site occupancy, relative to Al'¦

Jan 1, 1994

Companies involved in the mining industry are exposed to risks, referred to as corporate risks, as part of the business process. Directors and management should be aware of these risks and make appropriate business decisions to address each risk. If business risks are not addressed on a timely basis the consequences are likely to be serious and will adversely impact the ultimate success of the business.The key corporate risks are:Poor cash flow and treasury management. ò Incompetent or unmotivated staff.ò Poor product quality.ò Accounting systems that do not provide meaningful and timely information.ò Computer system deficiencies. ò Ineffective credit screening.ò Assets not adequately protected.ò New ventures undertaken that are either inappropriate or not adequately researched.Exposures to corporate risk should be dealt with by Directors and management by systematically identifying major risk areas and implementing appropriate internal and management controls to deal with such risk areas. Proper management controls and procedures include the setting of overall corporate objectives and policy, monitoring adherence to such policy, establishing early warning systems to highlight problem areas and maintaining security over assets.

Jan 1, 1990