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The determinants of human behaviour are numerous and complex. Many scientific disci- plines focus on various processes which play some part in shaping the actions of individ- uals and groups. Behavioural science attempts to synthesise data produced by these investigations in an attempt to formulate principles by which people's thoughts, feelings and actions may be described, diagnosed, predicted and changed. While no comprehensive account of people and their reactions can be attempted in a brief paper a review of six principles does provide a framework within which managers can establish reliable knowledge applicable to all their subordinates and to themselves. This information may be used to arrange organizational environments and management practices which enable people to discover, release and increase their best intellectual, emotional and motivational capacities.

Jan 1, 1982

By Osborn G

The bulk flotation behaviour of an industrial rougher bank has been determined with a view to characterising the size iepend ent behaviour of the identifiable nineral groups present. A relatively simple flotation model, based on first order kinetics and the assumption of perfect mixers in series ias been used to provide a fit to the operation of the cells. The adequacy of the model is discussed in relation to the characteristics of the ore and the size iependancy of the parameters. It is shown that improved fits are possible if the model accounts explicitly for this size dependancy and demonstrated how the model may be of use in prediction of the grade recovery relationships for different operating conditions as an aid to plant optimisation.

Jan 1, 1986

By D C. McPhail, S L. Rogers, J Brugger

Using iron- and sulfur-oxidising bacteria to catalyse the breakdown of sulfides that host the gold is an important biological method for the pretreatment of refractory gold ores. Following this biological treatment a combination of chemical and physical methods are used for leaching (such as the cyanide process) and concentration (such as carbon-in-pulp or electrowinning) of gold. Although these methods are well accepted by industry, they harbour limitations in the processing of low-grade refractory ores, and regulatory agency/public acceptance of cyanide use. Thus, it is beneficial to industry to develop environmentally friendly, cost-efficient leaching and concentration techniques that are based on micro-organisms. This may soon be possible by adapting the results of recent regolith geoscience research, which has shown that micro- organisms are capable of driving a biogeochemical cycle of gold dispersion, transport and reconcentration in the supergene environment. The indigenous microbiota in biologically active soil microcosms from a number of Australian sites are capable of solubilising up to 80 wt per cent of the gold contained in these materials during 50 days of incubation. Studies using molecular microbial techniques have shown that a metallophilic bacterium, Ralstonia metallidurans, is present in biofilms on gold grains from a number of Australian sites. R metallidurans is capable of actively accumulating gold from solution, suggesting that the bacterium may contribute to the formation of secondary gold grains and nuggets. Identifying the biochemical and physiological pathways that lead to the dispersion and accumulation of gold in regolith, and quantifying the reaction kinetics of these processes may thus lead to the development of industrial bio-processing capacities for gold-containing ores.

Jan 1, 2007

By McMahon D

The approach to valuations at the Normandy Poseidon Group is a measured and methodical process that utilises skills sourced from a number of different disciplines. Whilst being subject to a strict set of guidelines, it is also sufficiently flexible to be able to cope with the considerable variety across the resources industry. The group uses Discounted Cash-Flow (DCF) techniques extensively in order to develop a base valuation. Other external factors (eg the market) are, however, also taken into account when forming a view on value. Other methods of valuation are used in tandem or as alternatives depending on the task. DCF techniques are an important tool but would never be used in isolation. Considerable care must be given to developing the DCF analysis as its components (eg discount rate) are prone to misuse. Whilst the valuation process is quite detailed and scientific, it is really only as good as the inputs or assumptions (technical, financial, etc) that are used. The methodology used remains consistent whether the group is undertaking the corporate planning process or making an acquisition.

Jan 1, 1994

The treatment of slimes has of late years been the chief difficulty in connection with cyanide work, in which much time and money has been spent in endeavouring to find a practical solution of this problem.The processes at present in use are:-1. Filter pressing, as practised in Western Australia.2. Decantation, as practised in South Africa.Filter pressing after apitation affords a ready and efficient means of separating the gold bearing solution from the slimes and admits a perfect washing thus ensuring a high extraction but the very high working costs forbids its application except on high grade material, the chief items being the necessary large amount of labour, compressed air, and general upkeep, none of which can be materially reduced. The decantation method has the ad vantage of low working cost but on the other hand the low extraction obtained, due to imperfect washing, the length of time occupied in' the treatment, and the enormous bulk of solutions to be handled, are serious disadvantages.In either process it is absolutely necessary to obtain a perfectly clean solution before starting the gold precipitation by zinc, which is a source of much trouble. Also the high first cost of installing either plant is such that they can only be adopted on mines with very large working capital.

Jan 1, 1903

By A Horne, Z Graszkiewicz, D Dettrick, R Evan, B Neal

"Most of VictoriaÆs rivers and aquifers are already fully allocated or reaching full allocation. In regions without a well-established water market, access to water entitlements to facilitate new development is limited. In areas with established water markets, mine developers face an undue cost burden in circumstances where they are only planning to consume a fraction of the water entitlements that they purchase. The challenge for water managers is to ensure protection of water resources and other water users without creating an unnecessary disincentive for those types of developments that return most of the water that they take from water sources. The opportunity for development of a mine is explicitly linked to a particular location and must be developed where a resource is located or it cannot be exploited at all. Regulatory arrangements that facilitate development may have a positive impact on economic development, particularly where water availability is a potentially limiting factor. Net volume licensing has the potential to allow increased economic outcomes through improved licensing of access to water. Net volume licensing differs from traditional water licensing in that it authorises access to water on the basis of ænet useÆ rather than æthe gross volume takenÆ. This paper asks under what conditions net volume licensing is likely to be feasible and effective. In particular, the paper examines the information and accuracy requirements to allow net volume licensing decisions to be made. This work is based around five case studies in Victoria that were used to examine the potential for net volume licensing for mines and quarries. Assessing a potential net volume licensing arrangement requires the regulating authority to have an understanding of the inputs and outputs of water to a site. In contrast, assessment of take and use licences consider only a single input. It was concluded that the conditions that lend themselves to net volume licensing include: well understood water inputs and outputs, including appropriate accuracy of information where the location of site water inputs and outputs are the same where the timing of extraction and discharge can be managed to minimise impact on the water resource.A key remaining challenge is establishing an accounting framework that allows net volume licensing under current water resource limits. CITATION:Graszkiewicz, Z, Horne, A, Neal, B, Evan, R and Dettrick, D, 2013. The practicalities of implementing net volume licensing of water use in mines and quarries - a discussion based on Victorian case studies, in Proceedings Water in Mining 2013, pp 241-250 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 26, 2013

The injection of grouting compounds into the consolidated rock surrounding underground mine workings has long been practiced for the purpose of sealing against water flows. In more recent times however, grout injection has also found application for the purpose of rock mass reinforcement. Mines in Europe,America, Australia and elsewhere now make use of significant quantities of chemical grouts in both preventative and remedial strata control work.   Despite the increasing usage of grouting for these purposes, there is limited knowledge about the effects of grout injection on the rock mass, and acceptance of the method is by no means universal. In some cases grouting has been applied with little understanding of the factors that control its effectiveness, and disappointing results have been obtained.   This paper reviews the basic concepts of how grout injection may contribute to the control of rock surrounding underground mine excavations, and highlights the factors which may serve to limit the efficacy of the method and the uncertainties that complicate the appraisal of grouting as a method of strata control.

Jan 1, 1994

By Lawson F

Narrowly sized samples of synthetic chalcocite (Cu2S) and covellite (CuS) were leached in oxygenated acidic sulphate-chloride solutions. Chalcocite leaches via a two-stage process, the first stage being much more rapid than the second. The apparent activation energies are 42.7 kJ/mol and 68.2 kJ/mol respectively, indicating that both stages are controlled by surface chemical reactions. The leaching of covellite is also chemically rate limited with an apparent activation energy of 77.0 kJ/mol. The shrinking core model is able to be used to describe the leaching processes of both copper sulphides. Over 97% of copper present in chalcocite dissolved in 0.5 M H2SO4i0.5 M NaCl solution under one atmosphere pressure of oxygen at 85¦C in three hours from particles 36 pm in diameter while only 85% of the contained copper in covellite particles 13 pm in diameter dissolved in the same solution under the same pressure at 90¦C in six hours. About 99% of the sulphide sulphur in chalcocite was oxidised to elemental sulphur while only 90% of sulphide sulphur was converted to elemental sulphur during covellite leaching. The mechanism proposed for the two-stage leaching of chalcocite particles is as follows: in the first stage, cuprous ions rapidly diffuse to the external reaction surface where they lose electrons and go into solution as a complex cupric chloride ion CuCl'. The second leaching stage begins when covellite is formed at the external surface. Copper again goes into solution as the CuCl* ion. The mechanism for leaching synthetic covellite is similar to the second leaching stage for chalcocite except that the leaching rate of synthetic covellite is substantially lower than that of the newly formed 'covellite'. Elemental sulphur formed on the particle surface retards the dissolution processes during both chalcocite and covellite leaching. The presence of chloride ions is necessary if essentially all of the copper from chalcocite is to go into solution. When no chloride ions were present, the leaching rate of both newly formed and synthetic covellite was almost zero. The main role of chloride ions in both chalcocite and covellite leaching appears to be to disrupt the passivation film of sulphur on the particle surface.

Jan 1, 1989

A broker relies heavily on mineral valuations and independent experts' reports to provide the fundamental information, both technical and commercial, which provides the basis of estimating the sharemarket value of securities and underlying assets. It is important to appreciate the significant variance that can occur between the market value and other types of valuation at a particular point in time. In general, most experts' reports and valuations seek to provide estimates of technical/fundamental or ""fair"" value which correspond to the Corporations Law and accounting standards requirements. They do not usually attempt to estimate (stock) market values and it is usually and quite correctly the broker's task to estimate market values on the basis of a technical appraisal and consideration of all other commercial, market and financial influences. Therefore ideally, an independent experts' report or information memorandum will include material relating to commercial and management aspects of a company as well as detailed technical reviews and fundamental valuations. Wherever sensible cash flow projections can be made, cash flow-derived valuations, usually based on discounted cash flow (DCF) calculations, remain the preferred valuation methodology. Brokers in general would not argue with this preference. However, there is a paucity of examples of valuations where alternative methods are applied as a check on the reasonableness of a DCF-based estimate.

Jan 1, 1994

By Wright D. J

Successful heap leaching depends on three major factors: 1. Chemical conditions appropriate for the dissolution of the valuable metal; 2. Contact between the leach solution and the valuable metal particles; and 3. Movement of the leach solution through, and out of, the heap. Given that appropriate chemical conditions can be provided, and the individual particles have sufficient permeability to allow solute/solvent contact, the problem of getting the solution to and from the particles remains. Non-uniform percolation of solution throughout the heap, caused by the presence of fines, is a common problem which occurs, to some extent, with all heap leachable ore. The conventional solution to this problem is agglomeration, which involves the attachment of fine particles to larger particles, effectively modifying the size distribution by preventing the fine particles from acting on their own. While agglomeration must be considered as an extremely effective technique with virtually no limit to its application from a technical point of view, its application is limited by economic considerations. A new technique has been developed which is not only a low cost alternative to agglomeration, but also has the potential for enabling the application of low cost heap and vat leach techniques to a significantly wider range of ores than current practice would suggest. The new technique, known as Electrokinetic Leaching, utilises electro-osmotic flow to enhance percolation through the heap. This paper describes and presents results of the laboratory testing, pilot heap operation and commercial application of Electrokinetic Leaching of a low grade gold ore and a tailings deposit. Comparative cost analyses between conventional and the alternative processing techniques are presented.

Jan 1, 1994

By H Jones

Closure cost estimates may be generated at any stage of a mining operationÆs life; commencing with the initial prefeasibility studies and continuing through to the final decommissioning cost estimates. However, not all mine closure cost estimates are necessarily the same. Cost estimates will vary depending on the purpose for which they are prepared, the organisations requiring or undertaking the estimate and the stage of the mining operation. Different organisations can legitimately arrive at disparate cost estimates for closing the same mine because the organisations have different reasons for requiring the estimates. Another, equally valid, reason for potentially wide variations in cost estimates by different organisations on the same mine site is the different definitions of æclosure costsÆ used by different estimators. This paper considers the different approaches by different organisations including operating companies, government authorities and financial organisations and uses a hypothetical example based on practical experience to illustrate some of these differences in estimation methods.The paper suggest that a more consistent approach to closure cost estimating in the Australian mining industry would assist mining companies, governments, the accounting industry and the broader community to better understand this complex component of mine planning. One possible approach to closure cost estimating is briefly outlined.CITATION:Jones, H, 2012. Closure cost estimation - All things to all men?, in Proceedings International Mine Management 2012, pp 115-124 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

Being a geologist I intend describing the renaissance of the gold industry in Australia within its geologic framework; there is a geological pattern to the numerous gold projects which have been brought on stream over the past decade. We are now about midway through our third and largest gold boom which, at a peak of 7.5 million ounces is about twice the production peaks achieved in the preceding booms. From discovery in 1851 through 1870 we saw the first boom largely based on alluvial production in NSW and in Victoria at the great Ballarat and Bendigo Goldfields. The discovery of the Golden Mile in Kalgoorlie, Western Australia, underpinned the second gold boom in the period 1895 - 1915. On that basis the present boom should last through the next decade.   It has been a golden decade for Australian gold production. From less than ten mines in 1980 with production over 10 000 ounces and the largest, Telfer, with output of about 130 000 ounces we now find over 130 deposits being worked around the country today that produce over 10 000 ounces with the largest, Boddington, having an output of over 400 000 ounces. In total these mines produced an estimated 210 tonnes of gold in 1989 and we expect this year, 1990, that a new record production of between 240 and 250 tonnes will be set. This positions Australia in third place in the Western World behind South Africa #1 and the USA #2 and fourth in the world with the Russians holding second place overall behind the South Africans.

Jan 1, 1990

The production of metallic titanium and titanium-rich alloys in forms useful to the engineer involves the use of certain techniques not usually necessary in fabricating the commoner metals and alloys. However, not all stages in the handling and shaping of titanium-base materials require the application of unfamiliar methods. It is the purpose of this paper to indicate where the well-known techniques are applicable as well as to outline the unusual operations which are necessitated by certain chemical characteristics of titanium.In brief, the characteristics just mentioned are manifestations of the very great reactivity of titanium, especially at elevated temperatures. Liquid titanium burns vigorously when brought into contact with air. It also reacts with practically all refractories, causing damage to the latter as well as undesirable contamination of the metal. Even solid titanium undergoes serious superficial contamination when heated above 800°C. in air for more than a few minutes. In addition to an oxide skin being formed, oxygen enters into solid solution in the surface of the metal causing the latter to become hardened and eventually embrittled.Up to date, titanium has been made only on a pilot plant scale by methods which produce a spongy or powdered product. Refractory problems have prevented the development of chemical reduction methods for making titanium in the form of a liquid pool from which ingots of useful size could be cast. Therefore the first part of this paper will cover the consolidation of powdered or spongy titanium. The latter portion will provide a brief description of...

Jan 1, 1950

By R M. S Watsford, M Davis

In 2015, MMG Limited commenced further action to improve operating margins and establish a blueprint for future growth in the Australian environment. This action was taken in the context of weakening metal prices and high input costs that arose during the Australian minerals boom.MMG was formed in June 2009 following the purchase of the majority of assets of OZ Minerals Limited by China Minmetals Corporation (CMC) through its subsidiary China Minmetals Non-ferrous Metals Co Ltd (CMN).Since formation MMG has been implementing a business model to deliver a standard way of operating. The overarching purpose of the business model is to enable fast integration of acquired assets to realise improved productivity and performance. CMN established MMG as a vehicle to reach their growth targets through further development or acquisition of mineral assets in jurisdictions external to mainland China.The business model is underpinned by the MMG operating model. The operating model defines how MMG is arranged to deliver the company strategy.This paper describes the application of the operating model to the formation of the Australian operations into a single business unit from multiple stand-alone operating sites. The development and impact of the business model on MMG’s performance is also presented.The extension of the operating model to the Australian operations has led to improvement in safety performance, direct costs and productivity. These improvements have been achieved through reducing duplication, simplification of systems and rapid deployment of improvement initiatives.The successful implementation of the operating model to Australian operations strengthens the platform for further growth. Hence, delivering on the aim of the business model.CITATION:Watsford, R M S and Davis, M, 2016. MMG’s Australian operating model – the implementation, successes and learning, in Proceedings International Mine Management Conference, pp 291-302 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

By R Dunne, W McCallum

Continuous improvement might be defined as seeking incremental improvement over time through improved equipment, processes, technology and the efforts of people. Most people working in ore processing facilities embrace the general principles of continuous improvement. However, given the industry-wide issues with skilled personnel and the constantly changing environment in ore processing facilities, it is often difficult to identify improvements in a facility over a given time period. The driver for these outcomes is the use of basic principles and technology to achieve best practice targets. The process involves four stages: develop standards of practice to define best practice in specific areas; write procedures to guide the organisation towards these best practices; implement the procedures and develop a review process to provide a method of measuring performance against best practice.By reviewing performance against best practice on a regular basis, the organisation measures progress towards the best practice targets and the incremental improvement between these regular reviews is a measure of continuous improvement.This paper provides the background for developing standards of practice for metal accounting, metallurgy and metallurgical management. The paper also describes how standards of practice can be used to develop continuous improvement and the skills set of the departmentÆs leadership team.CITATION:McCallum, W and Dunne, R, 2012. Metallurgical management tools for continuous improvement, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 225-230 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By H R. Pein

"The Corridor Sands deposit is situated approximately 190 km north east of Maputo, Mozambique adjacent to the paleo-mouth of the Limpopo River. This deposit is one of the worldÆs largest known economically viable resource of titanium, accounting for approximately one third of the global resource. As part of the pre-feasibility and feasibility study for development of the Corridor Sands project, various geological and geotechnical investigations were undertaken, selected results of which are presented in this paper. These investigations have enabled a detailed understanding of the material characteristics of the orebody as well as the tailings materials, such as the fines, to be developed. These material characteristics have had a significant impact on the selection of the mining and disposal methods currently being implemented."

Jan 1, 2001

This evening I intend to explain the position of the gold mining industry in the light of post war trends and events.I propose initially to comment on gold production throughout the World and then proceed to the state of the industry in Australia, with an account of the efforts made within the industry to maintain levels of production. This will be followed hy a statement on assistance granted to the industry by Federal and State Governments.Annual World gold production is estimated at 51,000,060 fine ounces, made up as followsSouth Africa - 27,300,000 fine ouncesCanada 4,200,000 " "U.S.A. 1,500,000 " "Australia - 1,000,000 " " Others 5,000,000 " "----- 39,000,000 " "Estimated Russianproduction - 12,000,000 " "Total 51,000,000 " "The opening up of new highly payable mines during the post war years has contributed to the preponderence of production in South Africa.In 1962 some 24 new mines produced 73 per cent of South Africa's gold, and contributed almost 90 per cent to the industrial profits.At the same time, 20 old mines were struggling to main...

Jan 1, 1964

By A Valero, G M. Mudd

There is active debate and research around the most suitable indicators to assess the sustainability of mining. The most common approach is to report a range of data for a given mine site (or less preferably, a company total), such as inputs, outputs, benefits and potential costs. The most popular protocol in use (and growing rapidly) is the Global Reporting Initiative (GRI). However, these measures are numerous and still do not allow a single over-arching indicator to be developed. Other measures, such as known mineral resources over time, do not account for critical challenges such as declining ore grades, increasing wastes and poorer quality ores or more difficult mineralogy. By adopting a thermodynamic approach to sustainability, through the concept of æexergyÆ, it is possible to incorporate into a single measure the effective quality of mineral resources. Exergy involves the assessment of the minimum energy costs involved in producing a mineral resource with a specific chemical composition and concentration from common materials in the environment. The exergy of a mineral resource is evaluated from mineralogic composition, concentration (or ore grade) and, of course, quantity, by multiplying the unit exergies with the tonnes of the resource produced (or consumed). Since exergy is a thermodynamic quantity (ie energy or joules), it is additive across different minerals, such as iron ore to gold to copper or even oil and gas or coal û making it an ideal indicator to assess mineral resource sustainability at the industry scale rather than the individual mine scale. This paper briefly outlines the theoretical basis for exergy, and then presents a range of commodity case studies showing the application of exergy to the Australian mining industry. Overall, the usefulness of exergy is clearly demonstrated for use as a broad indicator of the sustainability of mineral resources at the national or even global scale.

Jan 1, 2009

Risk management has become an essential tool for mining companies to ensure their projects are well-managed and profit expectations are achieved. Risk management has also become a mandatory corporate governance requirement in Australia for publicly listed companies and equally important to attract investors. This paper provides a brief overview of the essential tools needed to implement a practical risk management framework to comply with the internationally recognised ISO 31000:2009 risk management-principles and guidelines from the perspective of small or soon to be producing mining companies. To?successfully?deal with the unknown and to manage the opportunities and risks involved with a mining project requires a clear understanding of the basic risk management principles. These include how to develop a project risk register, how to develop a project risk treatment plan and how to manage and monitor project risks to take full advantage of the opportunities presented.The first step is to identify and fully appreciate the risks that face a mining project. There are many risk identification methods that can be used including checklists, brainstorming and hazard and operability (HAZOP) studies. These often lead to a telephone book full of risks which are near to impossible to manage. A risk library specifically designed?for mining?projects containing no more than 100 risks will cover the major showstoppers, is practical and can be readily implemented and successfully managed.A risk framework also needs to be established which is compatible with the companyÆs structure and objectives. Once each risk has been assessed in regard to consequence and likelihood and the risk control systems are in place they need to be assigned to the responsible manager. The extreme or high risks will require a risk treatment plan to be developed. Risks will change during the life cycle of a mining project. Hence, a reliable monitoring system is also required for compliance.CITATION:Jones, J A, 2012. Mine project risk management, in Proceedings Project Evaluation 2012 , pp 117-122 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By T McLeod, B Catto

AngloGold Ashanti Australia’s (AGAA) Tropicana gold mine (TGM) geology department seized the rare opportunity of building a new geology department for a new operation: the philosophy, the people and the processes. Not satisfied with the status quo, or simply repeating what was familiar and already known, the vision was for an innovative, agile, multidiscipline, high performance team, capable of delivering on expectations.To achieve this, the geology department has operationalised key components of human resource management (HRM).This paper describes the operational design and implementation of key HRM components: job analysis, organisational design and organisational development. The benefits of this approach are presented in terms of engagement and autonomy in roles, opportunity for role variety and flexibility of the organisational structure. The result is a geology department that provides the functions of mine geology, resource development, regional exploration, survey, data management, geographic information systems (GIS), resource modelling, scheduling, sample preparation, resource coordination and hydrogeology, and even geotechnical engineering for a year!Considerations for application in other geology departments are presented in terms of fundamental requirements and lessons learnt. Fundamental requirements for success have been the sustained support of the general manager, valuing the scrutiny that comes with continuous improvement, high quality HRM systems and tools within the organisation, and a committed leadership group within the department. One of the most important lessons learnt is that a robust process of ‘induction to role’ is critical – the process of familiarising new starters with who we are and the way we work.CITATION:Catto, B and McLeod, T, 2017. Rewriting the rule book – geology organisational design, in Proceedings Tenth International Mining Geology Conference 2017, pp 137–142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017