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The emerging discipline of ægeometallurgyÆ is not new but is becoming increasingly recognised as a discrete and high-value activity that reflects an ongoing commercial and cultural trend towards more effective mine site integration and optimisation. The AMIRA International P843 æGeMIIIÆ project (Geometallurgical Mapping and Mine Modelling) is a major new cross discipline research collaboration designed to provide support for this emerging industry trend. The project is currently supported by 18 global mineral companies and involves collaboration between the CODES Centre of Excellence (University of Tasmania), JKMRC and BRC (University of Queensland) and CSIRO Exploration and Mining. These groups represent recognised research excellence in the fields of economic geology, automated core logging, advanced microscopy and process mineralogy, mineral processing, mine planning and resource optimisation. The needs and challenges of geometallurgy as an integrated activity will be outlined together with the ongoing contribution and aims of the AMIRA P843 æGeMIIIÆ project. The main emphasis is on development of predictive geometallurgical indices for key processing performance parameters that reflect inherent geological variability. The ultimate aim is to provide predictive indices of geometallurgical performance that can be confidently embedded into resource models and used for risk-defined mine planning and optimisation.

Jan 1, 2008

Cyanide is a significant contributor to the cost of producing gold. Any reduction in cyanide consumption that is achieved through more reliable measurement, and/or more efficient management of cyanide dosing rates, can produce a significant financial saving to the mine operation.

Jan 1, 1997

By Hutton W, Jack G. St

The Argyle Diamond Mines process plant incorporates a high level of computerised process control, and facilitates detailed performance monitoring. The control system was designed to provide a high degree of plant automation and a good quality interface to operators and management which includes control, data logging, graphics displays and detailed reporting. Performance monitoring techniques, both on-line and off-line have been developed to ensure circuit performance is optimised with particular emphasis on minimising diamond losses.

Jan 1, 1987

By Van Groenou B

Traditionally mining and conservation have been regarded as opposing and mutually exclusive concepts of land use. Often problems are anticipated which cannot be substantiated by facts. In addition, an ill defined time-scale adds to potentially emotive issues. Examples from Australia and elsewhere are presented which illustrate the dynamic nature of the environment and accentuate sequence patterns in plant community development following natural and man-made disturbances. The mining industry generally appears to be aware of the environmental impact of mining and whilst endeavouring to minimise the disturbance, is still orientated towards maximum production.

Jan 1, 1984

CABS - Costs and Budget System - is being developed to provide more appropriate tools to assist cost control. The most important of these tools is responsibility accounting, that is to ensure the respons- ibility for costs and budgets is placed at the lowest possible managerial level in the Company. The system design and computer techniques utilized include the use of on-line facilities for enquiry purposes plus entry and validation of data. Data base management is used to permit the complex relationships that exist between data in CABS to be defined and maintained. The system must be flexible in order to cater for organisational and other maintenance changes with minimum time delays. The major outputs of the system are reports produced in several cost dissections, by responsibility, by products by cost collection group and type of expense. A significant role in CABS has been played by users. This includes development, control and review of the system proposals in order to ensure that the objectives and requirements from all sections in the Company are met. This role has included Project Leader for the system plus a committee formed to provide formal acceptance of the system Design.

Jan 1, 1977

Information obtained from a reconciliation system provides fundamental indicators to an operations performance and is often neglected as a key performance indicator when developing a business plan or mining schedule. The cycle of exploration, ore definition, mining and processing within a company is constantly scrutinised both internally and externally as to the safety, environmental and financial performance of these activities with the operators judged on their performance on a periodic basis. However, it is not unusual for the reconciliation process to be given scant attention until a serious issue (usually a shortfall) occurs, at which point short-term solutions may be implemented which only serve to compound the original problem. A robust reconciliation system takes time to develop and implement initially and must continue to evolve with time. The best systems are those where all the stakeholders in the ultimate outcome are involved in the design and accept responsibility for the validity of their component inputs. Output from the reconciliation process can be utilised to fine-tune all aspects of an operation once the underlying issues leading to a particular result are understood.

Jan 1, 2002

When a major mineral find has been announced the general perception is that a battle between Aborigines and the mining company involved will inevitably occur.It is a fact that many miners in the past have not had a good relationship with Aborigines because of their indifferent attitudes towards them. They saw no common future and went their particular way. However, attitudes have changed significantly since Noonkanbah and both miners and Aborigines are seeking common ground in order to achieve mutual benefits from the establishment of a mine on or near Aboriginal land. There are many obstacles that both miners and Aborigines need to overcome inordertofindthiscommongroundtoachieveawin/win situation. The obstacles can be found in entrenched ideas and practices which need overhauling, not the least of which emanate from government policy and requirements.Without going into specifics, the Noonkanbah incident during the 1970's where Aborigines and their supporters confronted miners who were ordered by the Western Australian governmentto drill on Aboriginal land, polarized Aborigines and miners. Since this incident, many Aborigines, particularly those in the cities, have had the attitude that mining and Aboriginal culture are in direct conflict. Aboriginal opinion is generally shaped in the larger cities through mass media coverage of the opinions of urban Aborigines and their supporters. Through no fault of their own, these Aborigines were removedfromthe land of their ancestors and have notlived atraditional Aboriginal life-style for a number of generations and most have little knowledge of, nor have had involvement in, traditional Aboriginal lore and culture. For the most part these people live in awestern life-style and few still know their language. They generally have high profiles, often giving viewpoints that are wrongly considered "Aboriginal" and supposedly representing all Aborigines. This group is very different with their thought processes and values from those Aborigines who live on their own traditional lands with a traditional life-style, and practise their age old ceremonies. Their tribal values are based in their relationship with the land, expressed through complex religious ceremonial rites of song, dance and legend. Today this group is very much diminished in numbers but nevertheless in the region of the Gulf of Carpentaria there is a high proportion ofpeople who practise their lore, speak their own languages and pass on traditions to their children. It is well documented in the history of Australia that Aborigines have been decimated in numbers and whole tribes have been wiped out. Certainly in this region the experience has been no different.

Jan 1, 1993

University education in Australia is changing, driven by greater market orientation, reduced funding available per student, especially in the higher-cost minerals industry disciplines, and the call for more flexible delivery of subjects and courses to meet changing lifestyles and expectations. The opportunity exists for a true partnership to develop between industry, government and academia that will reshape minerals education in Australia and secure the future supply of the specialists industry needs to maintain international competitiveness. If this partnership does not emerge, it is anticipated that AustraliaÆs somewhat fragmented and unstable higher education system, especially in the disciplines of particular relevance to the minerals industry, will be put under further pressure so decreasing its effectiveness to produce quality graduates. The Minerals Council of Australia in 1998 published æBack from the BrinkÆ, a discussion paper which proposed strategies to build a world class minerals tertiary education system in Australia. Those strategies are now being implemented collaboratively with principal emphasis on the disciplines of mining engineering, metallurgy and earth science and as far as process is concerned, on the necessity to æcooperate to competeÆ. For metallurgy, the challenge is to integrate more closely undergraduate teaching with the existing world-class research centres and to link the tertiary institutions in such a manner that the strengths of all components are harnessed and then made available nationally in major population centres and at remote sites where appropriate. For industry the challenge is to build effective partnerships with the academic community that will enable and assist the agreed course of action to take place.

Jan 1, 2000

There is an established need for an inflow of foreign capital if New Zealand is to meet projected growth rates. The Government recognises this and encourages capital inflows especially where there are allied economic benefits such as the access to specialised know-how or export markets. The Government has promulgated certain Regulations which are administered by the Reserve Bank. Under the Capital Issues (Overseas) Regulations 1965, consent is required before any company incorporated overseas can commence business in New Zealand or before an overseas person can borrow or raise any money in New Zealand. A New Zealand company is deemed to be an overseas person if more than 25% of the voting power is held by non-residents. In terms of current policy, overseas companies are permitted to borrow in New Zealand only a limited amount of working capital and some longer term capital calculated on the ratio that their New Zealand owned equity capital bears to their overseas owned equity capital. Wholly owned overseas companies are expected to bring all of their Fixed term capital from overseas.

Jan 1, 1971

An extensive study was carried out to evaluate the performance of Outokumpu OK50, OK38 and Maxwell MX14 cells at ComincoÆs Red Dog flotation concentrator in Alaska. Tests were conducted by varying operating conditions of the cells installed in different circuits in the plant. The hydrodynamic and gas dispersion properties were measured and the metallurgical performance of the cells was evaluated for each condition used in the tests. This paper highlights the importance of superficial gas velocity, bubble surface area flux, gas hold-up, power consumption, residence time distribution and froth flow behaviour in optimising cell performance. The findings of these tests provide valuable insights into selection of the best cell operating conditions to optimise circuit performance.

Jan 1, 2000

The Ok Tedi copper and gold mining project is located in the headwaters of the Fly River system in western Papua New Guinea. The project's Feasibility Study was completed in 1979, and in- cluded a preliminary environmental assessment and an environ- mental management program. Construction commenced in 1981, an environmental impact study was completed in 1982, mining and treatment of gold ore commenced in 1984, staged construction of copper ore processing facilities took place during 1986-1988, and a further major environmental study was carried out for the operat- ing mine during 1986-1989. A very considerable data base of environmental information has been assembled by means of a comprehensive monitoring program. Environmental management criteria applied to the Project have reflected the stages and nature of development and operation. Criteria have been designed to regulate potential environmental impacts in the Fly River. An Acceptable Particulate Level of suspended sediment is the principal criterion. Compliance is con- ditional upon -a limited reduction in fish biomass, and upon dis- solved and particulate copper concentrations not exceeding predicted values at various locations throughout the river system. The criteria were established by the Government of Papua New Guinea following evaluation of environmental studies undertaken by the mining company. Compliance is checked by a detailed monitoring program, frequent reporting and statistical evaluation of monitoring results.

Jan 1, 1991

Before exploration programmes or minerals developments are formulated, a mining company ought to assess how capital can be returned if the project is successful. A fact not well appreciated by the minerals community is that it is often difficult to get money out of many Pacific Rim countries due to special foreign exchange controls or restrictions on dividend or capital repatriation. On top of this risk are factors such as creeping expropriation through administrative, fiscal, or corruption pressures; environmental regulations; terrorists; and organised labour and political activists. Political risk is much more than just expropriation or nationalisation.Political risk factors can make or break a project in many PacRim countries and just the cost of delays and negotiations can insidiously affect project economics. This unpalatable thought, however, can be readily addressed by either legal structuring e.g. offshore proceeds accounts, offset/back-to-back currency hedges, or political risk insurance for the equity as well as any subsequent project development debt.

Jan 1, 1990

Discovery 2000 is basically about data, its collection, management, assessment and dissemination. A major focus of Discovery 2000 is the collection of new geoscientific data. However, the Department is already a major source of data on the geology and mineral resources of New South Wales. These existing data when combined with the new data, will greatly enhance the knowledge of and information on the geology and the mineral development potential of New South Wales. This paper discusses some of the existing datasets and outlines how they can be accessed. It also gives an insight into the Department's strategy for data and information technology management.

Jan 1, 1995

There is growing acknowledgement that successful organisations, including mining companies, achieve their competitive advantage by better managing their employees, customers and other stakeholders. The fact that I have been asked to address this conference is perhaps evidence of the recognition of the importance of ensuring the improved management capabilities of the personnel within Australian mining companies. As many of you will be aware, prior to my appointment to the role of President of Minera Alumbrera Limited (MAA), the operator of the Bajo de la Alumbrera project, my career had been more generally focussed on industrial relations and human resources management. My appointment was met by surprise in some quarters, as it is unusual for a person without the technical background of a mining discipline to manage a world-class mining operation. However, it was recognised early in the life of the Alumbrera project that the operation did not lack technical expertise or a committed workforce; rather what was required was innovative management of the project and its operational resources, particularly given that we were operating with totally ægreenÆ workforce in a country without a large-scale mining culture. It is my experience that a particular shortcoming of mining companies is that they have tended to ægrowÆ managers based on their technical expertise rather than people management skills. Historically, many companies have assumed, or at least hoped, that their better technical people would develop the requisite skills to take on the challenges of management. Such philosophy has not always met with success. Whilst the topic for my presentation was originally published as People in the Mining Industry, within the context of the overall theme for this plenary session, People: Education for the Future, it is a subject with an extraordinary breadth of possibilities for discussion. Therefore, I have chosen to redefine my presentation to People Management Issues in Offshore Mining Projects,an issue which I consider to be an important area within the overall topic and one which has particular currency given the increased tendency by Australian miners towards offshore exploration. It is also relevant from the perspective of continued rationalisation of our industry, the recognition that there will be more large-scale, global corporate mining entities and that significantly more mining professionals will become æcitizens of the worldÆ. We therefore need to prepare our future leaders for these challenges. The topic also allows me to highlight the importance of an holistic management approach as the establishment of a new project in a foreign environment puts into stark relief the need for the application of the full range of competencies, rather than the narrow ætechnicalÆ approach to doing business. I hasten to add, however, that the mining industry is not alone in this regard and I was interested to read an article in the Weekend Australian of 22/23 January 2000, which reported on the first key speech of former Westpac CEO, Bob Joss, as Dean of the Stanford University Graduate School of Business. He said: à We know that when our students go out into the world, if they have to struggle, it will not be because theyÆre not smart enough, or they donÆt have enough good ideas. It will be because they struggle over managing themselves and their relationships to other people. The article then went on to say that Bob Joss foreshadowed an initiative to build alliances between the Business School and other Humanities departments within Stanford University to draw on their learning. Other business schools have also recognised this need, albeit somewhat late in the day, as have the most enlightened of modern corporations; in summary, successful businesses have recognised that in an age where competitive advantage through, for example, technological breakthroughs is very short-lived, it is the quality of management that will provide the leading edge. By using the Alumbrera project as a case study, I will identify certain of the challenges with which companies and individuals may be confronted in the establishment of a greenfields project outside Australia. However, many of the issues raised will have direct application in the context of the development of an Australian operation. My objective is to provide an indication of areas which should be considered at the formative stages of a projectÆs development, with particular focus on the issues of people management. I would expect that such a study would be of benefit to companies, education institutions and individuals in preparing themselves for similar experiences.

Jan 1, 2000

Since 1975 two electric hydraulic drills, a Robbins 11ND and an Atlas Copco C0P1038, have been part of the production drilling fleet at Mount Isa Mines Limited's Isa Mine. As might be expected with innovative and technically more complex machines, breakdowns and mainten- ance problems have been greater than those experienced with pneumatic drifters. This has been especially so with the COP1038 but in co-operation with Atlas Copco, many modific- ations have been made to alleviate operating problems. The training and quality of the maintenance workforce is of great importance. The use of coloured pictorial diagrams for hydraulic trouble-shooting will aid in minimising maintenance downtime. Both machines have achieved good operator acceptance. This is the result of many factors, the major ones being the more acceptable environmental conditions, the relatively low amount of physical effort and the high degree of mechanisation. The drilling area is one in which there is great potential for cost savings and product- ivity gains. Because both machines are capable of a high drilling output, Isa Mine is confident of achieving these aims.

Jan 1, 1978

It is suggested that if adequate knowledge is available about classifiers in closed grinding circuits, these units may be used as on-stream size analysers when equipped with suitable sensing devices. Research work which is at present in progress to enable a hydrocyclone to be used for this purpose is discussed.

Jan 1, 1967

By A R. Gerson

Pyrite, chalcopyrite and mixed sulfide samples, with and without quartz (5 wt per cent S), were subjected to column leaching to mimic natural weathering (cyclic wetting and drying). The pH and SO4 2- concentration of the column effluent was measured over a period of 78 weeks. The pH of the pyrite-only containing column rapidly decreased and remained under pH 4 after 12 weeks of leaching. The pH calculated assuming a 2:1 ratio of H + generation and SO4 2- release was slightly lower than that measured. However, a reduced H + to SO4 2- ratio of 1:1 is predicted if the release of aqueous Fe 2+ is assumed rather than the formation of Fe(OH)3. The pH of all columns containing only chalcopyrite or a 1:1 mole ratio of chalcopyrite and pyrite remained at or above pH 5 for the duration of the leach even though significant SO4 2- was released. One column containing the same initial surface area of pyrite and chalcopyrite but only approximately 0.10 the mole fraction of S as chalcopyrite maintained a pH of greater than five for the first 56 weeks of leaching and showed sporadic acid production thereafter. It is well established that oxidation of chalcopyrite results in a surface layer of polysulfide material. It is the formation of polysulfide that neutralises the acid produced on S oxidation through to SO4 2-. Hence where polysulfide formation occurs extensively on chalcopyrite the resulting solution pH decrease will be less than that based on SO4 2- production. The oxidation rate of sulfide minerals increases with decreasing pH and hence acid formation via sulfide oxidation to SO4 2- causes the subsequent oxidation rate to increase. The addition of calcite (CaCO3)to a pyrite column not only neutralises the acid formed but also decreases the rate of release of sulfate to solution by a factor of approximately 30. This is also the case where chalcopyrite is present mixed with pyrite. The rate of release of sulfate from the mixed sulfide mineral columns (after the initial release of the sulfate already present) was between one-fifth and one-tenth that in the absence of chalcopyrite.

Jan 1, 2003

It is always difficult to sum up an open forum adequately and instantaneously, so, with the privilege of hindsight, and also with some time to reflect, I am exercising the Chairman's prerogative to put together my view of the overall conclusions. Hopefully, these may provide a focus for each Institute to formulate its own programme with respect to mineral industry education. First, in answer to the question, "Should there be Schools of Mines?", there was a very clear 'yes'. However, I reiterate what I said in the introduction to this forum, specific professional education for the mineral industry exists only because the mineral industry sees a need and wants it. If the mineral industry should decide that it does not need professionals with specific mineral industry training, then such training will cease to exist. As alluded by Dr Hackett, if such training ceases to exist, one must then question the need for Institutes of Mining and Metallurgy. Now, there's some food for thought! Specialist schools of mines (metallurgy and geology) can only exist in an environment of genuine interaction with, and support by, industry. For their part, schools of mines, used here in a generic sense, require leadership that is strong but responsive to industry needs. It is the leader that puts his stamp on a school, and, to a large extent, determines whether that school is 'good' or only 'mediocre'.

Jan 1, 1986

By M Bezzina

In 1995 Standards Australia International Limited æSAIÆ published a risk management standard titled AS/NZS 4360 Risk Management. It was the first such standard published by a recognised formal standards body anywhere in the world and it put Australia at the leading edge of the risk management discipline. Many Australian and international organisations have utilised the risk management standard and it is one of SAIÆs most important and popular standards. Since its publication in 1995, the risk management standard has gone through a major revision in 1999 and is currently undergoing another such review, which is due for completion in 2004. This paper will chart the application of the standard within certain key organisations since its inception in 1995. A brief overview of the methodology behind AS/NZS 4360 will be presented as well as an overview of supporting and related standards. It is prudent to base risk management and other management system issues on existing and tested standards rather than creating new proprietary approaches. Examples of areas in which the risk management standard might be applied in the mining industry are given, subject to the specific operations of each company: technical, commercial, environmental, informational, and safety and regulatory.

Jan 1, 2003

By Sudharto RT

Sulphides of Cu, Pb, and Zn occur in quartz veins associated with a quartz monzodiorite stock at Gunung Limbung, West Java. The mineralization was polyphase and occurred at depths of less than lkm. Wall- rock alteration is extensive and typically consists of an outer zone of propylitization and an inner zone of potassic (K-feldspar- rich) alteration. Sporadic argillic altera- tion is probably of supergene origin. A variety of elements were mobilised during hydrothermal alteration and Ba in particular shows mared enrichments in the potassic zone. Fluid inclusions in the vein quartz indicate that temperatures of mineralization were within the range 250-3900C and that two fluids with differing chemistry were involved. One fluid had high Ca/Na ratios and a low overall salinity, the other had low Ca/Na ratios and a moderate salinity. The former is probably of meteoric derivation, whilst the latter had a magmatic origin. Precipitation of the sulphides was probably brought about by mixing of these fluids.

Jan 1, 1987