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By S Worden, P A. Kirsch, A Kirsch

Despite the current downturn, coal remains an important commodity in the Australian economy. Increasing coal resource development has resulted in increasing competition for land use in coal mining regions across the country with communities and other stakeholders becoming more adept at articulating their concerns regarding this competition in a range of traditional and social forms of media. In this environment, obtaining and maintaining a social licence to operate (SLO) is problematic and has been identified as the fourth greatest risk facing the international mining industry.This research presents the findings from a longitudinal study on how Australian newspapers frame the views of coal mining stakeholders across each stage of the coal mining life cycle. News stories from national, state and regional newspapers in 2000, 2006 and 2013 were analysed.Over the study period, there have been significant changes in the coal mining themes being covered by Australian newspapers, the number of stories being published, the number of newspapers covering coal mining stories, and the diversity of stakeholders being quoted. How do the dominant themes in media communication change over time? How do these changes impact mining across the life-of-mine?The research confirmed that Australian journalists use framing, priming, labels and bias to conceptualise and understand the events that they report, and that this behaviour has a profound effect on public opinion.CITATION:Worden, S, Kirsch, A and Kirsch, P A, ?2014. Moving beyond economic framing of the Australian coal industry, in Proceedings Life-of-Mine 2014 , pp 365–376 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By K Ringwood, J Cummings, C J. Moran

The development of a water accounting framework that enables consistent and contextual reporting of minerals operationsÆ water use, represents a key sustainable development objective that many Australian minerals companies have committed to. A future water accounting framework will require: key terms and definitions for water metrics for use in the Australian minerals industry that are consistent with the wider water sector, a suite of metrics representing key components of an operationÆs water balance, a calculation method for some of the metrics, and a reporting protocol. This paper presents the methodology that was used to derive these four components. Existing accounting frameworks were reviewed and key terms and definitions that were consistent with current regulatory requirements and voluntary approaches were proposed. A calculation methodology was developed to obtain some of the key indicators and variables that cannot be easily measured directly (eg water loss through evaporation). The adopted terms and definitions typically require a combination of empirical and estimated data. To test the proposed definitions and calculation methodology, values for water metrics were derived for eight sites, selected to test a variety of commodity and biophysical situations. The proposed framework and definitions could deal with the specific situations selected as case studies. The associated calculation methodology produced complete accounts at various levels. Some elements of the accounts could be directly checked against available data and simulations. The framework captured well variations in the reuse efficiencies; reuse efficiency could even vary for similar processes. It is concluded that this preliminary accounting framework provides a consistent language and metrics for quantifying and communicating water management, both at the intersection of the site with the surrounding landscape (through detailed reporting of site inputs and outputs) and within operational activities. Using this consistent framework for quantifying and documenting water use within an operation will provide a platform for compiling and comparing minerals industry water use with other sectors. This may support benchmarking activities within regions or companies and help demonstrate leadership amongst water users in water resource stewardship. The approach presented here is applicable to a wide variety of mining and processing activities, and biophysical environments, and following a period of stakeholder engagement and third party review, is being refined as a first step towards developing nationally consistent water use reporting for the Australian minerals industry.

Jan 1, 2009

Australian coals tend to be young in geological age and high in ash by world standards; preparation of the coal before marketing is almost universal. On the basis of float and sink data from 39 locations in the Eastern Australian coalfields, the coals are placed in four categories representing increasing difliculty in their washability characteristics. These seem to be related neither to the geological age nor the geographical position of the deposit and Hunter Valley coals, for example, span all categories. The influence of crushing on the washability of Australian coals is briefly considered and from limited data it is concluded to be appreciably smaller than for British or North American coals. A strategy for the float and sink analysis of Australian coals is proposed and the influence of washability characteristics on current trends in the selection of separating processes for coking and steaming products is discussed.

Jan 1, 1979

Study on Dynamic Characteristics of Inertia Cone Crusher and Its Application

Sep 13, 2010

By J F. Carswell, G Cheshire

The Pajingo gold operation in Queensland is approximately 55 km south of Charters Towers and 134 km south-west of Townsville. The gold deposit was discovered on the northern end of the Drummond Basin in 1983 and first open pit production began in 1986. Mining progressed underground in the 1990’s and gold production peaked in the early 2000’s as the main Vera/Nancy lodes were extracted, producing 330k oz in 2003 (a record at the time). More recently, as Ore Reserves and grade have diminished, the mine has had to develop innovative mining practices to maximise recovery of the remaining Mineral Resource. This has included a modified sublevel caving method against previously mined/backfilled zones. The method has been coined modified sublevel shrinkage (MSLS). Full scale trials of the new mining method have been successfully completed. This has allowed the site to revaluate the Mineral Resource and include areas into the Ore Reserve that were once deemed sterilised, adding significant value to the operation and extending its life-of-mine. This paper describes the first of two large scale MSLS trials and key operational learnings from it.

Mar 15, 2021

By A Scott, A C. Torrance

Explosive properties are typically summarised on manufacturers’ technical data sheets. The values most commonly referred to are the density of the explosive, the energy it is expected to release and its velocity of detonation (VOD). This information is provided so that blasting engineers can make a considered selection of the most appropriate product for a particular blasting application. As an example, a lower VOD and energy product is better suited to blasting in soft, weathered material. In contrast, blasting hard, competent material generally requires a higher energy product which is usually characterised by higher VOD and energy.A review of the technical information supplied by manufacturers shows a wide range of methods of reporting both VOD and energy. A meaningful comparison between products from different suppliers is almost impossible to achieve based on these data. For a similar product, one supplier may have a VOD range of 2800–5800 m/s and a relative bulk strength of 1.34 while a corresponding product from another supplier is quoted with a VOD range of 3100–6300 m/s and a relative bulk strength of 192. In the end, the user has to rely on the level of confidence available from their experience using a certain type of explosive in the type of rock to be blasted at that mine.This paper reviews some of the technical and supporting information that is freely available in the literature and attempts to provide some clarity as to what the numbers that are reported actually mean for the end user. An alternative approach to the evaluation of the suitability of a given explosive to blast a given rock mass is proposed.CITATION:Torrance, A C and Scott, A, 2015. What is relative about energy?, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 447–454 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By P Mesquita, A Nolan

Using a scientific-principled definition of global socio-ecological sustainability can be a useful basis for planning precious and base metal mining projects. The mining industry faces key challenges of; viability of the minerals industry; the control, use and management of land; national and local socio-economic development; environmental management; materials stewardship; and access to information. Using a framework for strategic sustainable development to assess the current reality of mine project development has resulted in identifying areas of strength and opportunities for improvement between current best practices and a desired vision of sustainability constrained by science based principles. These gaps indicate opportunities to strengthen current strategies, tools, and actions with a deeper understanding of socio-ecologic systems and a first-order, principled definition of sustainability, enabling success in moving towards achieving a sustainable society, ie sustainability. Evaluation of mine project development and their impacts on ecological and social systems using a systems perspective which recognises the underlying principles of operation, delays, feedback loops and response to change highlight specific opportunities to create value for social, economic and ecologic systems. Envisioning this future for mining projects within a sustainable society can be done by evaluating their development and operations guided by the sustainability principles. Performance indicators play a key role in measuring progress towards achieving sustainability goals yet it is necessary to consider whether indicators capture the whole systems perspective. Connected to this broader view, indicators can contribute much value to the mining industryÆs sustainability journey. This paper examines how current processes for mining projects can be developed using a whole systems perspective and measured using holistically designed performance indicators.

Jan 1, 2009

The distribution of tin and iron between slag and metal phases at about 1150°C was studied in pot scale experiments. The distribution coefficient k = (Sn/Fe) In metal X (Fe/Sn) in slag was found to vary from about 300 for metal corresponding to nearly pure tin, to about 100 for metal of about miscibility gap composition (17' 4 per cent Fe). Results conformed reasonably well to a straight line relationship between log k and (l-2NFe), as expected on theoretical grounds, and are consistent with thermodynamic data for the Fe-Sn phase diagram and the reaction Fe + SnO = FeO + Sn.Calculations are presented indicating the feasibility of smelting low-grade tin concentrates in a two-stage counter-current reduction process.

Jan 1, 1966

This paper is an outline of the developmental practices now in use at North Broken Hill Limited, N.S.W. The description will be given under the following headings.I. General.......opening up of a new level.II. Driving.III. Winzing.IV. Rising.V. Auxiliary Ventilation.VI. Notes on the Introduction of Mechanical Appliances.VII. Office Records and Routine.I. GENERALThe lode, for purposes of description, may be said to be divided into two portions which are usually referred to as the Southern and Northern Orebodies.The southern ore-body is the larger and in places attains a width of 200 feet. The northern ore-body is, generally speaking, comparatively narrow. These ore-bodies have a northerly pitch of approximately 45' and a westerly dip of 60. In the southern ore-body a grid of ore chutes is provided at 31 ft. 8 in. (5 square set) intervals and this necessitates an elaborate arrangement of cross-cuts, portion of which have to be driven through the foot-wall. Crushed country rock adjacent to the foot-wall makes it necessary for drives to be placed at least 60 feet from the lode.In the northern ore-body the ore chutes are arranged along a longitudinal drive, thus making a much simpler layout. These layouts were described in detail by A. R. West (Proceedings A.I.M.M. No. 117). In opening up a new level from the shaft plat, a heading is extended in a westerly direction until a point approximately 60 feet from the footwall of the lode is reached.At this point the direction of the cross-cut is altered to a bearing approximately 90 to the general strike of the ore-body, and the cross-cut continued until the hanging-wall is intersected. From the information obtained together with that from diamond drilling, the outline of the ore-body is plotted as closely as possible, and this serves as a basis for the layout of the level. Drives south and north from the main cross-cut are made in order to determine the southern and northern extremity of the southern ore-body. The former is usually driven in the centre of the ore-body and serves as a permanent gangway and ventilation drive for the new level.From the northern extremity of the southern ore-body, the drive north is...

Jan 1, 1944

By S Paciornik

Computer-controlled microscopes with digital image acquisition and analysis led to the creation of the new field of digital microscopy. These techniques not only allow a certain degree of automation but have also brought new possibilities to microstructural characterisation. One of these new and promising possibilities is co-site microscopy, which links different kinds of information obtained from different microscopy techniques. The present work presents the development and implementation of a co-site microscopy methodology that combines images obtained by reflected light microscopy (RLM) and scanning electron microscopy (SEM). This methodology can improve the SEM analytical capacity by adding colour information from RLM. It involves the whole sequence, from image acquisition at the microscopes to the analysis of the phases using pattern recognition techniques. An automatic registration procedure for the two kinds of images was developed, allowing the adjustment of magnification, translation, rotation and pixel size, and the correction of local distortions. Thus, the images from RLM and SEM can be combined to build a multidimensional data set of each field, which can then be used in a pattern recognition approach to discriminate different phases. The methodology was tested with a copper ore sample, aiming at the discrimination of minerals that are not distinguishable with either RLM or SEM.

Jan 1, 2008

The National Economic Viewpoint? Any substantial project undertaken by private enterprise would normally be subjected to a Discounted Cash Flow analysis of its commercial viability, and would proceed only if the rate of return was judged satisfactory. A 'national viewpoint' analysis attempts to do the same but from the viewpoint of the community as a whole. The objective is to ensure that those projects are undertaken which yield the best return, economic and social, to the nation as a whole.

Jan 1, 1984

By S Worden, A Lee Zhi Yi, E Sellers, G Corder, A Littleboy

The global shift towards decarbonisation is driving competition for the extraction of critical minerals such as nickel, lithium, and copper. To meet this demand, new mines are being developed while mines approaching closure are being reimagined as sites of potential resources. This reimagining challenges how mine closure is being conceptualised. In the conventional case, when a mine reaches the end of its economic life, it is closed or put into care and maintenance until it transitions to the next land use, such as agriculture, native ecosystem corridors, solar farms or integrated eco – precincts (Murphy et al, 2019; Holcombe, 2020) (the authors acknowledge that unplanned mine closures have left a devastating legacy of contamination, safety and cultural heritage impacts). Extracting minerals from closed or closing mines will extend mine life and, therefore, delay relinquishment and transition. In this context, innovative technologies are needed to make mining economically viable. In the first year of her doctoral research on improving stakeholder engagement in mine transitions, Lee Zhi Yi has coined the term ‘mine life extension technologies’ (MLETs) to describe a class of technological solutions that optimise extraction of resources after a mine reaches the end of its economic life. Examples of MLETs include agromining (van der Ent et al, 2015), in situ recovery (Robinson and Kuhar, 2018), and reprocessing or reuse of tailings (Gou, Zhou and Then, 2019). MLET extraction offers several benefits compared with conventional mining processes, such as waste remediation, value recovery of minerals, a smaller footprint and less environmental impacts (Sellers, Picorelli and Salmi, 2022). What requires further investigation is the consequences of MLET implementation to host communities or community perspectives towards the proposed technology and subsequent delays in transition.

Aug 2, 2023

By D M. Aranha, M A. Fonseca, M Echtern

The regional syndeformational metamorphism affecting the Itabira Iron Formation (IIF) at Quadrilßtero Ferrffero (QF) was formerly discussed by Dorr (1965), who proposed that quartz grain size could monitor the metamorphism, according to James (1955), and that the formation of haematite could be the result of the synchronous metasomatic process. Herz (1979) suggested the existence of three metamorphic zones, not mentioning the haematite formation. It could be observed that the primary oxide phase in the IIF is magnetite and most of the hard haematite was derived from the metamorphic replacement of magnetite, forming micaceous or schistose haematite. Differently from most iron formations in the world, the formation of haematite deposits at QF occurred under high oxygen fugacity during metamorphism. The haematite microlaths display a strong preferred orientation, which determines the alongated shapes of the fragments. The terms foliated and unfoliated haematite have been applied by Dorr to the micaceous or schistose haematite, and to the isotropic, hydrothermally derived haematite. Under the microcope, the haematite exhibits a strong crystallographic or lattice orientation encircling the magnetite and martite porphyroclasts. The strain rate determined and defined the textural variation, size and economic importance of the deposits and the ore grade. Metamorphism at QF increases eastward and resulted in the formation of a gruneritic Fe-Mg amphibole, at the western portion, followed by a cummingtonitic amphibole at the central-western part, succeeded by the actinolite zone at the central-eastern part, and finally to the tremolite-anthophyllite zone to the east. These zones, arranged in a north-south pattern, can be followed in the pelitic units, whereas appear sericite-chlorite, kyanite-chloritoid and garnet-staurolite respectively. Carbonate geothermometry in IIF also may support the metamorphic variations. At the western zone the haematite forms small lenses within the itabirite, P-contents are slightly higher than in the remaining IIF, haematite grain size is minute, resulting in a submicaceous texture and the amount and dimension of relict magnetite within haematite is greater than in the other parts of QF. Jangada and Serra Azul deposits are examples of this zone. The central-western zone is characterised by significant haematite deposits, in considerable quantity and size, haematite grain size increased, in order to produce a micaceous texture, the P-contents and the amount of magnetite decreased. Pico do Itabirito, Cappo Xavier, Capitpo do Mato and Tamanduß correspond to the deposit type of this zone. At the eastern-central portion the amount of the hard haematite deposits decreases, increasing the soft haematite ore due to higher strain rates. However, it can be perceived that the relict magnetite almost disappeared and the haematite grain size became coarser than the haematite from the western zones. At the eastern zone, the haematite deposits exhibit typical schistose texture, the magnetite porphyroclasts are absent and the lowest P-grades in the haematitic iron formation. The haematite bodies characteristic from this zone are Andrade, Morro Agudo and the deposits at the Itabira District. The hydrothermally derived compact and isotropic haematite deposits, formed subsequently to the micaceous haematite bodies, were generated after deformation ceased, but under very high fluid pressure. The metamorphic reactions magnetite + quartz + H2O = grunerite + haematite and magnetite + quartz + H2O = grunerite + O2 were decisive in the formation of the metamorphic haematite deposits.

Jan 1, 2007

The hematite deposits of Quadrilßtero Ferrffero (QF) are hosted by the Proterozoic itabirites of the Itabira iron formation (Harder and Chamberlin, 1915). These deposits are widely distributed at QF and include the hard hematite ore bodies. However, considerable variations in ore structure and texture can be observed. A preserved banding and lamination in the thin bedded, compact hematite ore, apparently reflects the original layering and/or the prominent foliation of the partly or completely replaced itabirite. The structure of the hematite ore deposits varies from almond shaped, rootless, to bedded bodies, both concordant with the main foliation, and to mesoscopic veins and irregular bodies. Hematite ore textures, which depends on the structural characteristics of the deposit, may be grouped into four main types:thin bedded, laminated and banded; micaceous, foliated and schistose; brecciated; and compact/massive. Thin bedded ores occur in the western, central and subordinately eastern portions of QF, while submicaceous, micaceous and schistose ores are predominant at the eastern part. Brecciated ores exist mainly at the western part and subordinately in central QF. Structureless, compact hematite ores may be either related to the brecciated hematite or occur as isolated bodies at central QF. It is suggested that a synkinematic, acid and oxidant, metasomatism during metamorphism, under a ductile regime, was responsible for the hard hematite ores of the types 1 and 2, and a static, subsequent, hydrothermal, regional metasomatism, under brittle regime resulted in the formation of the types 3 and 4. The common texture present in the all ores is the ubiquitous magnetite porphyroclasts replacement by hematite. Quartz and other silicate minerals are also substituted by hematite. Muscovite, tourmaline, talc, chlorite, apatite and kaolinite have been recognised in the hard hematitic ores. Apparently that mineral association denotes different equilibrium conditions of formation.

Jan 1, 2002

By J P. Sykes, A Trench

"World-class mine projects are increasingly failing to become world-class mines. Non-technical, socio-political and environmental problems seem, in part, to be the cause. However, the intangible and qualitative nature of these problems means overcoming them will require a greater systemic understanding of how the various technical and non-technical factors interact. This is particularly important as the concept of sustainable development has changed the industry paradigm sufficiently that it is no longer clear what world-class means. Finally, this better systemic understanding of mine projects needs communicating back to the exploration sector to improve exploration targeting.However, a disconnect between the exploration and mining sectors and between geologists and mining’s other professional disciplines means this is currently not possible. The use of economic evaluation techniques to assess the risk and value presented by the various technical and non-technical factors can assist with this by giving the varied professions a common language and including inputs from all disciplines. This paper therefore suggests a theoretical framework for analysing the various technical and non-technical factors, particularly the most challenging intangible and qualitative ones, and incorporating them into the typical economic evaluation techniques used in the mining industry.Understanding the risk and value relating to both technical and non-technical risks, however, places a greater emphasis on mining geologists to be conversant with a wide range of disciplines. Mining geologists will have to develop three types of knowledge:focusedinter-disciplinarybroad. In addition, they will have to become systemic thinkers to connect these types of knowledge. This multidisciplinary approach will require the use of fundamental critical thinking skills, common sense, intuition, experience and quantitative modelling techniques, dependent on the situation. As a result, both companies and professional societies, such as the Australasian Institute of Mining and Metallurgy, will have to develop ways of improving mining geologists’ inter-disciplinary and broad knowledge.CITATION:Sykes, J P and Trench, A, 2014. Resources versus reserves – towards a systems-based understanding of exploration and mine project development and the role of the mining geologist, in Proceedings Ninth International Mining Geology Conference 2014 , pp 243–270 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 18, 2014

During the extensive research which has been conducted in the Metallurgy Department of the University of Melbourne, into the properties of lead and its dilute alloys, the Brinell test has been used for the determination of hardness.The work described herein represents part of an investigation into the influence of various factors on such determinations, particularly when carried out on different qualities of "pure" lead. It is intended to publish the more theoretical and controversial aspects of this research elsewhere.MATERIALS USED AND THEIR PREPARATION FOR TESTINGThe tests to be reported have been conducted on a specially pure electrolytic lead, and several brands of commercially "pure" lead. The analyses of the samples upon which most of the work has been carried out are given in Table 1.Note: Oxygen was not determined, but from the work of H. W. Worner, in the Rosenhain Memorial Laboratory, it appears probable that it was approximately 0-0003% in all samples.

Jan 1, 1940

Salaries for mining professionals have gone up substantially in the last two years across most vocations and there has never been a better time to enter the industry, in terms of career opportunities and salary packages. With so many offers on the table and companies outbidding each other to attract the best talent, many new professionals are being lured in by the big money, sometimes at the expense of a satisfying career and a sustainable lifestyle. What should we consider when accepting a new position? What are our values, and how do these drive our decision making? This paper examines our core values as people and makes some observations about what it takes to really succeed in the mining industry.

Jan 1, 2006

By M Korte, J McMaster, C Brent

The Barrick Osborne concentrator has gone through a number of upgrades since commissioning and has increased production from the original 119 t/h design capacity to a milling throughput of 265 t/h in 2008. This was achieved incrementally over several years, by maximising operating efficiencies, in order to minimise capital expenditure, and take advantages of economies of scale; but more importantly it was reached with no measurable loss of recovery. Osborne currently processes a blend of underground and open pit material from the nearby Trekelano deposit. Following primary/secondary crushing, the material is processed through a rod/ball mill grinding circuit ahead of rougher/scavenger flotation that produces a copper concentrate. Osborne was seeking a further increase in plant throughput of the order of 15 per cent, but at more sustainable levels of secondary crusher plant utilisation. In early 2008, Osborne contracted Metso Process Technology and Innovation (PTI) to review the entire process from run-of-mine feed to final copper concentrate. This review would be done concurrently with surveys of both the crushing/grinding and flotation circuits being performed at the same time. The outcome would be a steady-state model of the complete flow sheet allowing the crushing/grinding model to interact with the flotation circuit model, such that overall process optimisation was possible. This was to apply both by exploring the operating limits of the currently installed plant, as well as looking at the logical next stage of capital plant expansions. Surveys of the crushing and grinding circuits were conducted at the Osborne concentrator in May 2008. The main objective of the surveys was to review the potential of increasing grinding throughput whilst maintaining the flotation feed 80 per cent passing size. This would also require improving the efficiency of the crushing circuit which was already operating in excess of 80 per cent of the time. Steady-state simulations were performed using the developed circuit models to identify opportunities to increase throughput and alleviate high circulating loads in both the secondary crushing and grinding circuits. Due to operational changes, the recommendations resulting from this project were considered by Osborne but have as yet only been partially implemented.  This paper covers part A or the crushing and grinding component of the project. A separate paper discussing part B or flotation is also being presented at this conference. The results of interactive simulations between the flotation and grinding circuit models are included in part B of this paper.

Jan 1, 2009

By Hellsten KJ, Butt CRM

Major Francis Hamilton Buchanan coined the term `laterite' (Latin; brick-rock) in 1807 for the red earths used for building blocks in southern India. Although these earths were actually weathered basalts, the term is now applied to weathering profiles developed upon a wide range of bedrocks. The Ni-laterites are a special class within the broad laterite family.

Jan 1, 1996

Major Francis Hamilton Buchanan coined the term `laterite' (Latin; brick-rock) in 1807 for the red earths used for building blocks in southern India. Although these earths were actually weathered basalts, the term is now applied to weathering profiles developed upon a wide range of bedrocks. The Ni-laterites are a special class within the broad laterite family.

Jan 1, 1996