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By P Storey, B Deans, T Lancaster

Straits completed its Feasibility study on the Whim Creek Copper Project in 1996. At this stage WCCP provided Straits with an open pit mine - heap leach - SX-EW copper project to follow on from its successful Girilambone Copper Operation (GCC). Since this time Straits has continued to review WCCP investigating a number of development and production scenarios. The development of Whim Creek, early 2004 and is on schedule to commence copper production in the final quarter of 2004. On current reserves Whim Creek will produce approximately 17 000 tonnes of copper cathode per annum for three to four years, at cash costs of The paper will cover a general description of the project, the project development and key design issues. Additional construction related issues associated with the complete relocation of the GCC plant to Whim Creek will be covered in the conference presentation.

Jan 1, 2004

The prospect of utilisation of phosphate ores which contain high P2O5 values associated with Al and Fe has produced a great deal of interest over many years. Processing options have generally been based on the utilisation of by-products which were required to offset the processing costs.   This paper presents a range of processing options which have been investigated at laboratory or technical scale on phosphate ores which predominantly consist of crandallite, CaAl3(PO4)2(OH)5.3H2O and millisite, Ca(NaK)Al6(PO4)4(OH)9.3H2O. Christmas Island (Indian Ocean) and Mt Weld (Western Australia) phosphate ores are good examples of such feedstocks. It is expected that these processes may also be applicable to such phosphate ores from other locations.

Jan 1, 1990

The value of water is defined by its marginal utility. Challenges arise where the marginal utility is difficult to estimate. Therefore, when two or more interested parties wish to access water and they cannot use commensurate units for marginal utility; other means of value comparison must be sought. It is asserted here that sustainability principles can be used to guide this valuation if this is supported by a transparent decision framework. This paper proposes that the ICMM sustainable development principles provide appropriate guidance. In addition, a generic framework for decision making is suggested as a complement. Indicators of water management are recognised widely as an integral part of the accountability of minerals companies towards meeting sustainability goals. Less widely recognised are the ways in which sustainability principles can be used to guide decisions on water management which demonstrate growing awareness of its value. This paper illustrates the use of this logic in water issues associated with global sustainability challenges. It then goes on to demonstrate, using examples, that these links exist at all levels of the minerals industry and that indicators of this type are potentially as powerful as those currently being used. The reason for this is that the path from cause to effect is transparent and direct.

Jan 1, 2006

By J P. Ashby

Compared with elsewhere in the world, New Zealand quarries have tended to be mostly small. The reasons for this are a combination of the relatively high transport costs, low population density and a pioneering, self-employed attitude. The small size of the operations is reflected in low productivity, a tendency to repair and rebuild equipment rather than replace it, designed flexibility in the processing plant, minimal reserves investigation or development planning and a versatile and innovative work force who are generally not professionally trained. The Resource Management Act and the Health, Safety and Employment Act as well as a customer driven demand for higher quality and consistent products will have even greater influence upon future direction of the Industry. The trend will be towards fewer quarries operated by companies and professional managers that can adapt to the new demands.

Jan 1, 1993

By Whiten WJ

A method that allows data to be mass balanced and screen models to be fitted in a single step is described. The inclusion of several variables to describe the feed data in the fitting procedure allows a mass balance to be conducted at the same time as the fitting of the screen model. Analysis of Groote Eylandt Mining Company screening data has demonstrated that this method is ideally suited to applications where complete stream data are not available. Also, certain random fluctuations in screen model parameters arising from the fitting of consecutive mass balances and screening models are significantly reduced. A cubic spline function with fixed knot positions corresponding to particle sizes and variable (fitted) cumulative percent passing values is used to describe the feed size distribution. When the spline function is interpolated at the experimental feed particle sizes a fitted feed size distribution is obtained. This feed size distribution is then used as input to the screen model calculations from which product size distributions are generated. Since both feed and product size distribution data are used to minimise the residual errors between the observed and fitted stream size distributions, a mass balance is Conducted simultaneously with the screen model parameter fitting.

Jan 1, 1984

By M J. Nugus

A substantial cost is invested into the data collection phase of any exploration or development program; notwithstanding, it is impractical to expect a database of information can be collated to ensure a perfect geological interpretation. The question then becomes, is there a possible alternative interpretation and what is the likely impact of the variations? Modelling in 2005, of the Cosmo lode at Sunrise Dam Gold Mine, Western Australia led to consideration of the philosophical implications associated with resource management. It was concluded that several plausible geological models could be constructed from the known geological database. To varying degrees, this predicament is common to all geological reconstructions, as several alternative geological models can be generated at almost any stage that will impact on the resultant resource estimation and mine plan. The significance of that variation and the associated risk of multiple geological models (MGMs) requires due consideration. What is being suggested is that using plausible multiple geological models advances the holistic understanding of a mineral deposit within the bounds of the data collected, providing fluidity for updating geological knowledge and building inherent variability into the design and planning departments where variations of the geological models may materially impact on the resource performance.

Jan 1, 2006

It has been fairly firmly established (Fisher, N. H., 1945) that the fineness of the gold in any ore deposit varies with the depth from the surface at which the deposit was formed, and, as a corollary to this, that it is dependent upon the temperature and pressure at the time of deposition. This relationship is such that, under certain conditions, the gold fineness, taken into consideration with other recognised criteria, furnishes a very sensitive and reliable guide to the relative temperature of ore formation, at least within the epithermal and the upper part of the mesothermal range.Definition of Fineness.The fineness of gold is calculated in parts per thousand and refers to the proportion of gold present in the naturally occurring metal in the lode, which is actually a gold-silver alloy, containing usually about 10 parts per thousand of base metal and up to 500 parts perthousand of silver. A clear distinction should be made between fineness and gold-silver ratio. The latter refers to the total gold and silver in the lode as determined by assay and is usually expressed as the ratio Au:Ag. Only in deposits where other silver-bearingminerals are entirely absent, which occurs comparatively rarely, can the gold-silver ratio be used as a measure of gold fineness and, in many cases, the two have no relationship. For instance, in the Edie Creek area in New Guinea, the lodes formed under shallow epithermal conditions all carry gold 500 to 550 fine, although the gold-silver ratio ranges from 1:100 to 1:1, in places in adjacent lodes.Determination of Gold Fineness.The fineness of lode gold can be determined only after it has been separated from all other minerals. Amalgamation recovers gold fairly cleanly - unless native silver is present - and the fineness of amalgam bullion is generally a reliable indication of the correct fineness of the gold. If the use of plates is involved, the bullion may be adulterated, but the effect of any copper, or other metal, that may have been introduced can be cancelled by assuming that the gold and silver shouJrl add up to about 990 fine, or by ignoring the base metal content altogether, which varies little in naturally-occurring gold, and in calculating for comparison purposes all fineness figures to the basis Au + Ag = 1,000.The composition of bullion obtained from cyanidation is generally intermediate between the true gold fineness and the total gold-silver proportion as determined by assay of mine or mill-head samples of Cyanide solution dissolves other silver-bearing minerals and the fineness of the resulting bullion is thereby lowered. Consequently, the fineness of cyanide bullion rarely corresponds to the true gold fineness and is useless for diagnostic purposes, although it is a common fallacy to refer to the fineness of cyanide bullion as the fineness of the gold.

Jan 1, 1950

The relationships between Aboriginal Traditional Owners and mining companies have often been mired in dispute, particularly since the High Court Mabo decision and the Native Title Act of 1993. In the Pilbara region, Rio Tinto Iron Ore (RTIO) impacts the traditional country of 12 Aboriginal Traditional Owner/language groups. Over the past 12 years the company and the Traditional Owners have negotiated and settled several significant land use agreements including the Yandi Land Use Agreement over the Yandicoogina mine in 1997, between Hamersley Iron (now Rio Tinto Iron Ore) and three language groups û the Bunjima, Nyapaili and Innawonga people and the Eastern Guruma Indigenous Land Use Agreement (ILUA) of 2006. These substantive agreements are now being followed by a new generation of region wide ILUAs which are close to conclusion. Arising from these regional agreements is a new framework for engagement which has been informed by the implementation of the previous agreements in the Pilbara and across the Rio Tinto group of companies. They are driven by both a company desire to have a consistent approach to engaging with Traditional Owners and the Traditional Owners wanting to have a similarly transparent and consistent standard of performance by the company in implementing the agreements which can deliver improved employment, cultural heritage engagement and direct and indirect benefits for the life of mining by the company. During the past three years the growth in the Pilbara, Western Australia brought new opportunities with people flocking to the region for employment flowing from the mining boom. Housing was at a premium and FIFO (fly-in, fly-out employment arrangements) was developed as a method to manage the general growth and demand for skills. Despite the recent down turn in the world economy since September 2008, which has reduced demand for minerals, the Pilbara continues to enjoy high levels of employment and as a result there is still significant pressure on housing and services provision. Although there has been vast economic growth in the Pilbara not only by mining companies but also oil and gas companies, the 2006 census data indicated that the direct benefits of improved employment, business development and engagement in the mainstream economy continued to exclude Aboriginal people. Indigenous people constitute a significant proportion of the population in the Pilbara region, some 6000 people û currently 14 per cent of the population rising to 18 per cent by 2015 û yet they remain at the bottom of the socioeconomic scale. More than 40 years of mining has returned relatively little to this group of people who are the permanent residents of the region and are connected through their traditional culture to this country (Taylor and Scambary, 2005). Ensuring local Aboriginal participation in the mainstream economy has been a challenge for resource companies, Traditional Owners and local residents in the Pilbara. The case study explores the relationship between a mining company û Rio Tinto Iron Ore and the Traditional Owners of the Pilbara. It examines two projects that have been developed to engage Indigenous people in the development of their region and through regional representation and business development to build a sustainable future for themselves and their future generations and at the same time ensure social cohesion to support social licence to operate. The case study also examines the process that was followed by Rio Tinto Iron Ore and its operations in undertaking a regional agreement for land access, participation and the integration of local Indigenous people into their business and the local economy.

Jan 1, 2009

By R Valenta, J Owen, D Kemp, E Lebre, G Corder

Copper plays an essential role in our society. It is one of the key materials supporting economic growth and human development in emerging economies, for its common use in construction, power generation and transmission. It is also a critical metal for the transition to a low carbon future, particularly for its uses in renewable energy and electric vehicles. As a result, global demand for copper has been increasing steadily and is predicted to continue in the future. The demand-supply gap is currently growing, and new mines will be needed to fill it. This project observes the current pipeline of copper mining projects, which are characterised by technical complexity (lower grades, deeper deposits, complex mineralogy etc.) but also environmental, social and governance (ESG) complexities. A common assumption in the mining industry is that a rise in copper prices will unlock these deposits. However, while most technical complexities are price sensitive and are likely to be overcome in favourable economic conditions, the influence of ESG complexities is more difficult to evaluate. CITATION: Lebre, E, Valenta, R, Kemp, D, Owen, J and Corder, G, 2018. Accounting for social and environmental complexities in mining project developments: the case of copper, in Proceedings Complex Orebodies Conference 2018, pp 39–40 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By Wittenberg J. C, Reid A. F

A method is described for the rapid and effective production of polished section mounts of ore and mineral particulates to the standards required for automated image analysis. This requires mounting without segregation of particles by mass or density, and it is also preferable to avoid having particles in contact so that they can be recognised as individuals. To achieve this, the particle samples are first split to an appropriate degree in a rotary riffle, and the sub-sample mechanically diluted and thoroughly mixed with an inert filler of the same size range as the particles. Just sufficient epoxy resin is added to make the mixture fluid. During setting, the ore particles are mechanically supported by the inert filler particles, thus maintaining the particles in a random three-dimensional distribution. A rapid two-stage grinding process, based on the successive use of 600 mesh silicon carbide and 1200 mesh (10 um) corundum on cast iron plates, is followed by three stages of mechanical diamond polishing on cloth laps. Hand polishing is entirely avoided, as is the use of papers.

Jan 1, 1984

Bougainville copper concentrate was leached with a strain of Thiobacillus ferrooxidans (SPKI) in a 5 per cent CO2 nitrogen atmosphere.Copper solubilization was 100 per cent in presence of bacteria and only 30 per cent in a sterile acid control medium.Anaerobic copper solubilization rates were one quarter of those measured under aerobic conditions and did not generate acidity.

Jan 1, 1985

Discovered in 1954 and mined since 1966, the X41 copper orebodies have produced over 143 Mt @ 3.3 per cent copper. By June 2002 the production from these orebodies had depleted the Mineral Resource to 36.6 Mt @ 2.8 per cent Cu (including 31.5 Mt @ 2.5 per cent Cu combined 2002 Ore Reserve). Mine production will ramp down to cessation beyond ten years. The 2002 Copper Business Study was commissioned to review the status of the Mount Isa copper business and to optimise the long-term strategy of the operations. The study resulted in a vastly improved geological and geostatistical model, and financial studies led to the optimisation of mine cut-off grades. Utilising these new models, a near-mine target generation workshop was conducted by the copper stream geology team. The workshop focussed on exploration for new ore sources and the extension of existing orebodies to supplement the Mineral Resource inventory for future conversion to Ore Reserves. Several prospective targets were identified and the Conceptual Northern 1100 Drilling program was subsequently designed. This paper shall discuss the practicalities of near-mine target generation in Mount Isa, the issues faced when locating and preparing drill sites in a mature mine environment, and the preliminary results of the drilling program so far.

Jan 1, 2003

By J Stiefenhofer

"*This is an abstract only*Construction of geological models for kimberlites has historically largely been based on visual volcanic textures and features, with chemical data only collected on an ad-hoc basis depending on the level of perceived complexity observed in the geological data. The focus of this paper is a high-level view of the impact an initial absence (or lack) of relevant chemical data had on two kimberlite resource models as well as how the magnitude of the problem increased once the resource estimation process commenced (Stiefenhofer, 2013). The impact of ignoring chemical data on a project assessment where micro-diamond estimation techniques are employed, is also discussed. Resource estimates based on micro-diamond data are critically dependent on the use of the correct geological model since stationarity of the size frequency distribution is key to the generation of correct grade estimates. A multilevel approach is advocated where the volcanological/visual model is verified using chemical data and both are in turn verified by the diamond data.CITATION:Stiefenhofer, J, 2013. The use of chemical and metallurgical parameters to enhance the economic value of kimberlite resource models, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013, pp 101-104 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 29, 2013

Cleaner Production stands for a proactive and preventive approach to industrial environmental management and aims for process- and/or product-integrated solutions that are both ecologically and economically efficient (æeco-efficiencyÆ). Pioneers in the field were large manufacturing and processing industries in the USA (since the late-1970s), but it took until the early-1990s before Cleaner Production was generally recognised as a valuable approach for large and medium sized enterprises. The application of Cleaner Production in mining and minerals, metals and energy production appears to lag behind other sectors, such as manufacturing and processing. This paper starts with a discussion of the Cleaner Production concept and provides examples of its application from a few selected Australian mining and minerals processing industries. This evidences that Cleaner Production can achieve significant reductions in environmental impact, in terms of reduced waste and emission generation and in terms of conservation of materials, energy and water, while simultaneously reducing operating costs. The paper then investigates a number of key issues pertaining to the implementation of Cleaner Production; ie organisation and management of Cleaner Production activities, effective tools for mastering the Cleaner Production concept as a way of life, and performance measurement.

Jan 1, 2002

In southeastern China, offshore Tertiarybasins are buried underneath the broad continental shelf areas from Taiwan to Hainan Island. These basins bear relatively similar characteristics of structure, stratigraphy and tectonics. Based on age and tectonic framework, these Tertiary basins are divided into two groups of Paleogene basin and Neogene basin (Fig.1 and 2). However, observations of extensional structures indicate that the Paleogene basins are rift basins; and the predominant structural features are NE-SW trending half grabens and fault blocks. In a regional scale, these half grabens and adjacent uplifts represent a horst-and-graben structural style. Neogene basins are downwarp basins lying on the tilting continental shelf. Late Tertiary sequences are relatively undeformed but locally with minor folding and thrusting during the Pliocene-Pleistocene.Seismic stratigraphy and well data indicate that the Early Tertiary strata are commonly tilted and disturbed as nonmarine to marginal marine facies deposited in the wedge-shaped half grabens; the Late Tertiary strata are generally parallel undisturbed marine facies accumulated in the enlarged downwarp basins overlying the infilled half grabens. In general, three major regional unconformities formed during the Late Cretaceous, the Late Eocene and the Middle Miocene. Widespread extrusive basaltic flows are commonly associated with these unconformities.

Jan 1, 1990

Before any accident prevention and total safety programme can succeed, a safety concientiousness or attitude needs to be implanted in the employees' minds. Psycholog- ical and physiological conditions play a vital role in accident causation and prevention. Both need attention in a good safety programme, but working place conditions and environment are more easily corrected. However, the challenge is to change attitudes in the minds of men - psychological factors in accidents. To do this does not require a Safety Officer, but does require a Safety Adviser. At Blackwater mine a Safety Adviser is available to all sections of the organisation to guide and assist, to provide data and material to use at meetings, to help in accident investi- gations and to help organise training. To eventually achieve total commitment requires every member of the management team to be a salesman towards all around selling an attitude to safe working, a way of life. At Blackwater mine the workforce is young overall with most employees being under 40 years old. Psychologically this is a quite different problem to a balanced ages working group. A great deal of effort is needed to communicate with the younger, articulate, better educated employee who is also generally a skilled operator in the capital intensive

Jan 1, 1975

By Batterham RJ

A 'research model' can be used to investigate cause and effect relations and generally improve the understanding of extractive metallurgical processes. As such, it is a useful research technique which complements the traditional methods of laboratory and plant measurement. The procedure of model development is iterative and involves observation of the process, hypothesis of phenomena, prediction using mathematical descriptions of the phenomena and comparison of predictions with real-world measurements. Lack of agreement of predictions with real-world measurements usually indicates an inadequacy in the hypotheses and necessitates revision. Experimentation has an integral role in the process of model development but its emphasis is different from that when experimentation alone is used to study processes. Since a process as a whole is investigated by using a model, experimentation is restricted to the study of specific phenomena to aid the description of these in the model, to the characterisation of the raw materials (for initial values of the model parameters) and to the measurement of physical and chemical constants required in the model equations. Similarly, plant measurements are made for the purpose of comparison with the model predictions not to establish cause and effect relations. This makes plant experimentation much simpler and cheaper'since most measurements-can be taken during normal operation.

Jan 1, 1984

In order that the processes seen may be followed in their proper 'order, the subject will be dealt with as follows, (1) Wallaroo and Moonta Mines; (2) Wallaroo and Moonta Mines Smelting Works; (3) Broken Hill Mines; (4) Concentration at Broken Hill; (5) Smelting and refining of Lead, Silver, and Gold at Port Pirie. The first acquaintance with the copper region was made at the Yelta shaft and dressing mill of the Parramatta Copper Mines Co. at Moonta. The country rock at Moonta is a hard, tough, felsitic porphyry, the copper lodes having a general strike of N. 30° Kilipping from 500 to 70°. This necessitates shaft-sinking on the lode, and underlay shafts are the rule on the field. The ore is raised in the Yelta shaft in wheeled skips, and consists of ·chalcopyrite, bornite, pseudomorphic hematite, containing, in addition, molybdenite and tourmaline. The ore from the bins at the brace is passed over a grizzly; the over-size is hand-picked into smelting ore, concentrating ore, and waste rock (00 attle ), which is sent below for filling. The under-size is elevated to a trommel having in. holes. The over-size falls on to a picking belt made up of lengths of rope strapped with iron, working over wooden pulleys.

Jan 1, 1907

The following notes apply more especially to the purchase of silverlead ores produced in the neighbourhood of Zeehan and Dundas; for it is this class of ore that is principally mined in those parts, and which creates competition among the ore buyers.In the early days of this field, most of the ore passed through the hands of the first buyer who had sufficient enterprise to establish himself at Zeehan but in more recent times, competition has been so keen that there are generally three or four buyers tendering. lf the output was large this would not matter so much from the buyers' point of view but when we consider that the output of the field is only some 1,650 tons per month, and that of this 70 odd tons are produced by the Western and Montana mines, aud being sent home for realization, is withdrawn from local purchasers, there is really not enough for four buyers, especially at the present exorbitant prices they pay the miners.Some of the mines have a fixed sampling day, on which it is tacitly understood that the ore buyers will attend. Others, such as Grubb's Silver Mining Oompany, No-Liability, send round a printed reminder, stating the quantity of ore, and the date of sampling.

The mineralogy of nickel slags from the flash smelter of Western Mining Corporation Ltd. at Kalgoorlie was studied. Residual magnesium silicates in the sulphide concentrates raise the melting point of the slag and result in the formation of magnesium-rich olivines. Addition of lime lowered the melting point, and, in slowly cooled slags, resulted in the formation of a pyroxene.Magnetite and sulphides were also present in all slags.The converter slags contained an olivine near fayalite in composition, together with wiistite, magnetite, and a little sulphide.Accretions from the hearth of the flash furnace were largely composed of magnetite with subsidiary olivine similar in composition to those of the flash furnace slags.Wall deposits, however, were largely composed of nickel ferrite and nickel-iron olivines.

Jan 1, 1976