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Monazite sand is processed at the rate of 25-30 tons per week at Rare Earth Corporation of Australia's plant at Port Pirie. Main products are rare earth concentrates of cerium, lanthanum and yttrium. By-products are commercially pure water soluble thorium sulphate and tri sodium phosphate. The more recent developments in volume rare earth applications are Discussed.

Jan 1, 1972

Concepts of facies are of proven worth in sedimentology, but have hitherto received little attention from volcanologists. The time is now ripe to develop facies schemes for volcanic products. This paper discusses possible facies applicable specifically to lava flows and ignimbrites, the intention being to explore possible approaches to the problem of recogniz- ing volcanic facies rather than attempting to develop a comprehensive facies scheme

Jan 1, 1987

By King D

Recent field experiments in the United Kingdom (Buchanan, 1979) have shown that the in-seam technique is capable of detecting a 1m fault in a 3m seam, at a range of 280m and with a resolution of ¦40m. Comparable tests in Australian collieries are proceeding. Although the practicality of an implementation of the technique on a routine basis remains to be demonstrated, the potential of the technique for the prediction of outbursts clearly warrants detailed examination. This potential will,depend, inter alia, on the level and scale of variations in elastic (and anelastic) properties of bodies of coal undergoing stresses associated with mining. Available data, mainly from studies of the seismic properties of gas saturated reservoir rocks, confirm the intuitive view that stress increases give rise to increases in seismic wave velocity and decreases in wave attenuation, markedly at low stresses (as pore spaces close with little resistance) but less so as stress increases. Such increases are of the same order as aniso- tropic effects, but should provide impedance contrast sufficient for detection by in-seam seismic methods. At higher stresses, cracks form within the rock mass. Results from research on earthquake prediction provide some clues to the behaviour of sedimentary rocks sub- jected to large stresses. In particular, the

Jan 1, 1980

Average annual growth in consumption of primary energy in Australia over the past 10 years has been 5·5 per cent compared to a world average of 4·1 per cent.Over the next 10 years growth rate is expected to increase to 6 per cent per annum due largely to the rapid development in the mineral processing industry.By the end of the 19705 natural gas is expected to supply more than 9 per cent of Australia's primary energy market. Coal will supply 40 per cent and petroleum products 47 per cent. Nuclear energy will make its appearance but will make only a small contribution in the period.Australia has adequate reserves of natural gas and coal to supply its needs in the 1970s and beyond. However the newly developed reserves of crude oil, while supplying 60-70 per cent of requirements in the initialyears, will need regular and sizable additions if they are to keep pace with the expanding consumption. For Australia to become self sufficient in the period 1970-1990 it is estimated that new discoveries will need to approximate ten times the volume of recoverable reserves found in Australia to date.

Jan 1, 1971

By D S. Clarke, W M. Prebble

Potential waste rock products from the mining of epithermal deposits in the Hauraki Goldfield are characterised to facilitate their management. Hydrothermally altered andesites and their weathered near surface equivalents have been examined from the Golden Cross, Karangahake and Monawai gold deposits. These materials vary in both their clay content (smectite, illite, kaolinite and chlorite) and the degree of silicification resulting from alteration and weathering. The simulated degradation (slaking tests) of waste materials cannot be explained purely by consideration of clay content, siliciflcation, or the resultant variations in porosity.   Microstructure is considered to be essential in predicting the physical degradation of waste rock. The scanning electron microscope is an effective tool in such an investigation. Increasing alteration results in clay particles becoming more randomly orientated (matrix microstructure); this causes a reduction in the surface area of contacts between components resulting in increased potential for degradation. The extent of skeletal microstructure (commonly characteristic of weathering) is an important control on effective porosity and the long term potential for degradation. Management requirements for these materials include the minimisation of moisture content variations (with the prevention of initial drying being of primary importance) and the containment of sediments produced.

Jan 1, 1991

In underground ore mining of copper ore, lead-zinc ore, tin ore and fluorspare in German Democratic Republic geological situation is characterized by ore deposits of small thickness and great variability of ore grades and mining conditions. For long range mining strategy and short-term planning of production a model was developed fitting to make optimal economic mining decisions. Starting point of the model is a cost function representing all direct costs per unit recoverable metal in concentrate for each stoping unit (ore reserve block). In the costs function the results of regression analysis of ore grade and metal recovery in concentration plant were considered. All stoping units (ore reserve blocks) of a mine were arranged to growing direct costs. The relationships of recoverable metal, ore tonnages and corresponding costs were plotted in a diagram. The data processed by- computer and the graphic representation of the results make possible 1. economic evaluation of stopes and ore reserve blocks, 2. estimation of cut off grade, 3. optimization of works planning.

Jan 1, 1977

The quality of the external water source for a mineral processing plant may influence the extent to which the environmentally desirable practice of recycling of water from plant products is possible. This is particularly likely for froth flotation plants where the chemical quality of the water may affect the plantÆs performance. The quality of the external water source or the recycled water can be improved by a water treatment step, and in turn the extent of recycling which can be tolerated is able to be influenced. The quality of the external water can range from very high quality, soft water derived from melting snow, to poor quality, hard water (high levels of dissolved calcium and magnesium) from underground aquifers, and to even lower quality sea water (very high levels of dissolved species including sodium chloride). It can be noted that some underground water is more saline than ocean water as well as containing high levels of dissolved calcium and magnesium. Occasionally, a different source of water is utilised in the wet and the dry seasons. Increasingly, sewage water from cities is becoming a potential external water source with sustainability implications. If the initial quality of the external water is high, the scope for recycling of water from all the products is maximised. Such reuse or recycling of water from the products allows chemical species from oxidation of the ore and from other inputs to the process such as reagents to increase in concentration in the water returned to the plant. Such accumulation of species can have negative effects on the performance of a process such as froth flotation but instances of positive effects exist. Some reagents which are used in flotation plants such as lime or sodium carbonate also happen to be commonly used for independent water treatment plants. Hence, the flotation process may inadvertently provide some aspects of water processing. Where the quality of the water in the feed to a mineral processing plant (external water plus recycled water) is not an issue, more powerful solid-liquid separation processes can be considered to maximise the removal of water from the products and its reuse. Such processes may also have complementary benefits in a sustainable mineral industry by, for example, producing a tailing stream with a higher per cent solid value which is more suitable for safe storage on the surface or underground. This paper documents findings on the effect of water quality on the flotation process. It also considers current directions of change in the need for increased removal of water from plant products. It then considers the implications of these trends for maximisation of water recycling by such operations.

Jan 1, 2003

By Gang C, Changyi S, Liangde G

Geophysical and geochemical methods and techniques for gold exploration and their applications in China are summarised in the paper. Some case histories are also presented. The effect of prospecting for gold deposits using these methods is well illustrated through these examples.

Jan 1, 1997

I must tell you at the outset that I come to this conference deeply disturbed at the `role of Government in international dealings in mineral and energy resources'. I am disturbed by the confusion that now passes for policy. I am disturbed by the short- range view of critical problems taken by a majority of Governments. I am equally disturbed by the even shorter range of view taken by a growing army of industries. Many of them clamour for Governments to solve their problems in a specific way, with little regard for any other sector but their own-and with even less regard for the fact that every time a Government takes over some of their responsibilities they surrender some of their freedom. I would not say that longer range views don't exist. But I would say that they don't prevail at the present time. Instead, we are seeing the con- stant development of many policies for individual problems which don't tackle the fundamental causes. We must get back to basics without delay.

Jan 1, 1978

Designing and constructing OxianaÆs Sepon gold and copper operations in one of the most remote areas in Laos has been a great achievement; one which was recognised by the engineering industryÆs highest accolade û the Australian Engineering Excellence Award in 2005. The developing nation of Laos has no previous mining or heavy industrial experience, but the support of the Lao Government and a remarkable Lao workforce has enabled the project to be developed and operate as well as it would anywhere else in the world.When making a decision to invest offshore, several geophysical and jurisdictional criteria need to be considered. Laos offers unparalleled prospectivity, a central location with growing infrastructure, a ready workforce and a developing but supportive regulatory regime. In addition, the Sepon copper project has exceptional characteristics, including its high grades, location near the surface, leachable qualities, access to hydropower and the ability to produce cathodes on site. These attributes and its location in the centre of a region hungry for resources contributes to the projectÆs excellent economics.

Jan 1, 2006

By Parker C. J, Mikula P. A

The excavation for the Sydney Opera House Parking Station comprises a large donut shaped underground cavern with a central sandstone pillar. The maximum effective roof span is about 19 m and the rock cover is between 7 m and 8 m. Permanent support for the roof and the various services tunnels consists of a combination of tensioned anchors, and untensioned dowels, and mesh with shortcrete and fibrecrete as the final lining. Steel sets were installed at main intersections.Fundamental to the design philosophy for excavation of these spans at such shallow rock cover was the use of monitoring to check on the adequacy of the installed support. Prior to excavation, extensometers, inclinometers, piezometers and surface settlement survey stations were installed. Underground survey stations, anchor load cells and shotcrete pressure cells were installed as excavation proceeded. Excavation commenced at the crown using an initial heading and three widening stages. Geological mapping during excavation confirmed borehole expectations, namely sandstone beds 1 to 4 m thick interbedded with thin shale units. Bedding plane contacts varied over short distances from tight partings to thick brecciated seams. Jointing was subvertical and joints tended to be bed-limited.

Jan 1, 1993

With the next mining boom looming, the industry will once again struggle to meet skills needed as the current generation boomers are set to retire. In order to meet these needs it is going to need to focus on what underutilised human resources - in particular women - want!   Women comprise around 14 per cent of the mining workforce, compared with a 45 per cent participation rate in the work force overall. Within the industry, women still make up only one per cent of trades people, eight per cent of operators/production employees, 12 per cent of engineers and 11 per cent of executive management.   It may be worth pointing out that mining has an age profile skewed towards the older end of the spectrum. When it comes to employee retention, what women want may be a good starting point to examine, more broadly, what all employees might want (but are too afraid to ask!).   Women in mining want the following: To be scrutinised for their work and performance, not their personal lives, appearance or relationships. True pay equity. This is addressed at lower levels between companies but at professional levels the salary differentials begin to appear and little is done to identify why this continues to be the case. Recognition and acceptance that women can have different work-styles, and that diversity of work-styles is an asset to be nurtured not a threat to be neutralised! Recognition that a more diverse workforce demographic that better reflects society at large will assist the company in its dealings with many diverse stakeholders from society at large. For employers to recognise that a career break to accommodate caring responsibilities does not mean that an employee's commitment to progressing their career is any less than that of someone who has not taken a career break. Similarly, for employers to recognise that working part-time for to accommodate caring responsibilities does not mean that an employee's commitment to progressing their career is any less than someone who works a more traditional roster. Access to affordable and quality child care compatible with mining rosters in mining towns. Zero tolerance for bullying and harassment, and workplace cultures that promote respect and safety. This is an ABSTRACT ONLY no paper was prepared for this presentation.

Jun 1, 2010

By S Gray

Based on the 2021 Volume 5 State of PlayTM mining survey of key executives and board members in the mining sector, the key responses to ‘Which of the following technologies will have the biggest impact on mining in the next 15 years?’, were ‘Sensing and Data’ followed by ‘AI and Analytics’. From the early 1970s it would have been unlikely to predict the level of sensing and automation introduced to the broad industrial sector. No better example is the automobile industry where the combination of technological advances and external drivers (such as emissions control) have driven an incredible rate of change. The introduction of sensing, data, AI, and automation in the mining industry is just ramping up. Until now our energy efficiency, environmental footprint, labour shortage, skills, and safety have not been challenged by stakeholders in the way we are seeing market forces develop today. In order to address these challenges, we need to look back to the automobile industry and learn their lessons to accelerate our application of digital capability, analysis, AI and automation This is critical, particularly as access to skilled human resources becomes more difficult. An example of how this can be achieved in a gold processing plant utilising the latest real-time sensing technologies is the ‘Carbon Scout’ developed by Curtin University, and OLGA developed by CSIRO, which are both online technologies, coupled together with Gekko’s ‘Neon’ digital platform to achieve a fully automated real-time gold processing system.

Aug 24, 2022

By A Sturgess, P McKenna, P D. Erskine, D Doley, V C. Glenn

For more than four decades, rehabilitated lands in the Bowen Basin have been planted with buffel grass (Cenchrus Ciliaris), which is often used to provide rapid, stabilising and erosion reducing cover to reshaped landforms (Erskine and Fletcher, 2013; Harwood, Hacker and Mott, 1999; Grigg, Shelton and Mullen, 2000; Naidu et al, 1997). Historically introduced to Central Queensland and encouraged by pastoralists in the early 1900s (Humphreys, 1967), the species has been extensively used by mine managers in seeding mixes (Coaldrake and Russell, 1970; Edye, 1975), and the invasive nature of the grass has led to the monodominance in rehabilitated areas of semi-arid Central Queensland. With 40 open cut coalmines in Central Queensland (Department of Natural Resources and Mines, 2015), a considerable amount of land is either disturbed mine footprint (156 200 ha) or rehabilitated (29 200 ha) (Dale, 2015), and the bulk of rehabilitation consists of relatively young (<30-year-old) developing ecosystems, with demonstrated biomass fuel loads up to 20 t/ha (Grigg, Shelton and Mullen, 2000).Uncontrolled fire poses a significant risk to rehabilitated landforms that are located in close proximity to mining infrastructure, neighbouring communities, open pits with exposed flammable coal seams and flammable stockpiled coal resource. Mine lease holders in Queensland have the added responsibility of managing and protecting any endangered regional ecosystem communities, and flora and fauna listed federally under the Environment Protection Biodiversity and Conservation Act 1999 or the State Vegetation Management Act 1999; as well as, any culturally significant sites such as scar trees or middens that are found on-site. Additionally, uncontrolled fire in rehabilitated landscapes poses a significant risk to mine site closure goals, with the potential to create altered states and stalled ecological trajectories (Grant, 2006). CITATION:McKenna, P, Glenn, V, Erskine, P D, Doley, D and Sturgess, A, 2016. Fire behaviour in buffel grass dominated mine site rehabilitation in Central Queensland, Australia, in Proceedings Life-of-Mine 2016 Conference , pp 158–162 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

Process mineralogy is an inter-discipline in the fields of mineralogy and mineral processing. As a predicting and trouble-shooting tool, process mineralogy helps address all mineralogical issues and problems related to mineral processing. It provides useful information on process design and optimisation, flow sheet development and cost reduction. As more and more complex and refractory ores are being discovered and processed, it is believed that process mineralogy will gain more attention and play a more important role in process design and optimisation. This paper will first discuss the scope of process mineralogy and mineralogical factors that may affect mineral processing of various ores, and then focuses on the application of process mineralogy in process design and optimisation through case studies.

Jan 1, 2008

By S Doyle

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Macraes gold mine in Otago, New Zealand, is developed along the central portion of the Hyde-Macraes Shear Zone (HMSZ), which dips gently to the NE, and is traceable over 30 km of strike, before disappearing under tertiary cover. Mineralisation is most intensely developed along the hanging wall shear, which defines the upper limit of the shear zone, although significant packages of quartz vein arrays and mineralised shears occur sporadically beneath the hanging wall shear.The Macraes gold mine is now in its 25th year of operation, well beyond the projected mine life at the time of commissioning in 1990, and currently contains over triple the measured and indicated resource inventory that was defined at start up. The extended mine life and resource growth has been driven by exploration and resource development success, efficient low-cost mining and processing, improving gold price, as well as an ethos of continuous improvement.The emphasis of Oceanagold’s exploration and resource development has shifted over time; from hanging-wall-focused mapping, soil sampling and step-out drilling, through exploitation of previously drilled stockwork mineralisation, to the pursuit of blind, higher-grade underground targets.Mineralisation within the HMSZ remains open at depth, and the regional potential has not been fully tested. Given the relatively low-grade of gold mineralisation at Macraes, the consideration of tungsten as a supplementary co-product provides an exciting opportunity.CITATION:Moore, J and Doyle, S, 2015. Resource definition in the world-class Macraes gold mine, New Zealand, in Proceedings PACRIM 2015 Congress, pp 557–564 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

The implementation of robust, reliable and accurate sampling systems is the key to the successful management of any mineral processing plant. The representative sampling of a mineral processing plant is the only way to determine what is coming into the plant, what is going out as fi nal product and what is going to tails. In plants with high gravity gold components, where high recovery effort gravity circuits are installed, the use of a gravity recoverable gold (GRG) sampling system can assist in the online monitoring of the performance of the circuit. The typical installation location would be in CIP or fl otation feed (ie cyclone overfl ow), downstream of the gravity circuit. A GRG sampling system generally consists of the following equipment: true proportional, continuous drive, linear cross cut sampler, secondary vezin sampler operated on a timer, a batch centrifugal concentrator, and sample dewatering module. The operating philosophy of the GRG sampling system is that the primary sampler operates on a continuous basis, generating a constant stream of truly representative sample. Consep's H&S drive system is unique in its ability to be able to operate in a continuous mode, therefore enabling a continuous stream of representative sample to be generated. The primary sample stream reports to the secondary sampler. The secondary sampler operates on an intermittent basis (nominally ten minute interval), resulting in a relatively small sample volume per shift. Normally the sample volume would be ten to 15 L per shift. The secondary sample rejects stream reports back to the batch centrifugal concentrator. The sample generated from the secondary sampler can be dewatered using a Consep H&S dewatering module. This device produces a final sample that consists of separate filter cake and filtrate. These are suitable for taking directly to the laboratory. The continuous stream of truly representative secondary sampler rejects is passed through an appropriately sized Knelson Concentrator, typically a KCMD7, KCCD10 or KCCD12 sized unit. This unit recovers any available GRG from the stream. The Knelson Concentrator is also purged of its gravity concentrate at the end of the shift. This sample, which is nominally around 1 - 2.5 kg of concentrate, is also taken to the laboratory. At the end of the shift the client will have a measure of the gravity recoverable gold content of the target slurry stream, as well as a true representative sample of the complete stream. Through the addition of a Knelson Concentrator to an otherwise typical sample station, it is possible to generate a true measure of the performance of your gravity circuit. This will take the guess work out of the daily variation in gravity circuit gold recovery, as the site knows whether the changes are due to gravity circuit equipment performance, or due to the natural variation of ore GRG contents. Maintenance planning can also be designed around the system, as the site will have a composite sample to measure the performance of the circuit, therefore indicating where performance has dropped and maintenance is needed. This is an ABSTRACT ONLY. No paper was prepared for this presentation.

Aug 1, 2010

By C Sylvestre

For the last 50 years, traditional safety management has improved safety performance by: • Fixing the environment (eliminating the hazard). • Improving the system (more/less rules, procedures etc). • Making safety more conscious (more/better interactions about the importance of safety). Although these approaches certainly have merit, and may be part of an overall solution, they are not enough to prevent many modern-day incidents. Today, these three approaches are used more than before, and are used better than ever before. Yet, workplace fatalities in Australia have stagnated from 2013 to 2019, as have the number of incidents, even serious ones. In the USA, workplace fatalities have increased by 15 per cent in the same period.

May 5, 2022

By R J. Higgins, M Edraki

What is the meaning of the Life of a Mine (LOM) if that mine results in a requirement for water treatment in perpetuity? ‘In perpetuity’ is of course a duration with no relationship to a Life-of-Mine or what might rightly be regarded by external stakeholders as a fair and reasonable post-mine recovery period. It exceeds the life span of investors, mine managers and governments, indeed even of capital markets as we know them, and of corporate and individual memories.In mine and mine closure planning, decisions are usually based at least to a significant extent on traditional economic analysis underlain by discounted cash flows (DCF). For investments in income-producing facilities, such as mining development and equipment, and ore-processing plant and equipment, this analysis reflects commercial reality and allows for comparison of competing investments. However, for environmental and social infrastructure, the same analysis using the same input parameters, especially the discount rate applied to cash flows, can lead to a bias against the adoption of best practices for non-investor stakeholders. CITATION:Higgins, R J and Edraki, M, 2018. Water treatment in perpetuity – or not?, in Proceedings Life-of-Mine 2018, pp 131–132 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By A Kite

Frontline leaders play a critical role in the safe and productive operations of Australia’s mining, resources and heavy industries. These leaders set the workplace culture, especially during night shifts and weekends, by providing team direction and encouragement, providing access to resources, fulfilling statutory requirements, enacting and reinforcing risk management systems, setting the standards on shift and acting as the primary conduit of communications between senior leaders and team members.

May 5, 2022