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By A Kamkar-Rouhani

The paper describes a mineral potential mapping of gold and other base metals in Mahneshan area, Iran, using geographical information system (GIS), in which, the method of weights of evidence is used to combine spatial data obtained from different sources to make prediction for mineral potential. This is a quantitative tool for mineral resource mapping that can be used to delineate and predict favorable areas for further exploration by using the characteristics of known and similar mineral deposits. In accord with the descriptive model for gold and other base metal deposits, the spatial distribution of 20 known mineral occurrences was used. In addition, digital evidential maps were used in this study. The maps include maps of lithological units, faults and first derivative of total aeromagnetic data, remotely-sensing data of alteration and also geochemical evidential maps produced on the basis of the results of chemical analyses of samples taken from the stream sediments in the area, and analysed for Cu, Pb, Zn, Sb, As, Ag, Au, Ba and Hg elements. The binary maps were produced and then combined with the model of weights of evidence using 20 known mineral occurrences to obtain a final map of the favourable areas for further exploration of gold and other base metals in the study area. The final map is a predictive GIS model of the mineral deposits in the area. An interesting matter about the final predictive GIS model is that the faults are mainly located in favorable areas which possesses the most probability of mineralisation. Therefore, the faults in these areas have priority for further exploration of gold and others base metals.

Jan 1, 2005

Residual aeolian placers (RAPs) are formed by the wind, by preferential entrainment and removal of small and low-density detritusfrom a pre-existing, typically sedimentary sequence containing heavy minerals. Heavy minerals that are resistant to chemical alteration and either soft and malleable (gold), or extremely hard (diamond, sapphire, ruby, etc), are concentrated as a residual on the wind deflation surface, typically in the interstices between larger resistant clasts. RAPs form preferentially in arid or semi arid areas, where the vegetation is sparse or absent, and where topography and surface gradients are low, but may also form on beaches and in periglacial environments. RAPs consist of a continuous or discontinuous, planar or gently undulating horizon of heavy minerals in a single-clast-thick pavement of resistant pebbles, cobbles, or boulders, which mantles the present topography or palaeo-topography. Extreme wind erosion and surface deflation may condense the full pre-existing sequence into a layer of heavy minerals only. The grade of RAPs is substantially higher than in the precursor deposit, and commonly much higher than those typically found in most other placer types. Aside from their general occurrence as a thin pavement of resistant clasts, the best indicators of residual aeolian gold placers are the presence of wind-eroded stones (ventifacts) on the pavement, and the distinctive and unique shapes of aeolian gold grains themselves. The shape of the gold grains is progressively transformed by sand blasting during placer development, from grains with thickened rims, to toroidal grains on which the rims are æsplitÆ and peened inward toward the grain centre on one or both of the grain sides, to hemispherical or sub-spherical grains that are fully encapsulated by the in-turned rims. Gold that has undergone aeolian shape transformation is difficult to entrain and transport away from the site of aeolian concentration by anything other than mass movement or glacial processes. It is also easily retained by commercial recovery plants of any configuration.

Jan 1, 2004

By R L. Brathwaite

The mesothermal quartz-scheelite lodes of the Wakamarina valley are one of twelve known mined or prospected gold-bearing areas in the Marlborough Schist. Recorded production was 556 kg gold, a little silver, and c. 390 t scheelite. 134 m of the 1800 m long Golden Bar reef are accessible in the No 2 level of the Golden Bar mine. The reef is a typical multi-banded mesothermal vein, mostly c. 1.75 m wide, enclosing narrow horses of schist country rock. Scheelite is sparsely distributed, and is more common in small veinlets in the hanging wall schist. The country rocks are textural zone I-1m schists of prehnite-pumpellyite to pumpellyite-actinolite metamorphic facies. Their geochemistry suggests they are part of the Caples Terrane, and of calc-alkaline volcanogenic arc origin. The associated Wakamarina Quartzite is strongly recumbent folded, and of the same metamorphic grade, with abundant pumpellyite, stilpnomelane, and garnet, presumably spessartine. Although it has geochemical signatures of a deep sea sediment, it is depleted in Cr and Cu, and greatly enhanced in K and Ti, when compared with a standard chert. It also has trace element characteristics of a calc-alkaline arc-related sediment. However, associated greenschist has MORB-like incompatible element chemistry. The Golden Bar reef lies within a steeply dipping, normal to transtensional dip-slip fault adjacent to a shallow-dipping mylonite shear zone, which, at least on the footwall side, is 040 m wide. The shear foliation has been severely dragged down to nearly parallel the Golden Bar reef within 1 m of the quartz lode. Preliminary structural analysis suggests that the shear zone is extensional. X-ray diffraction analyses of the wall rocks show a progressive depletion of amphibole, stilpnomelane, and pumpellyite towards the reef, and enhanced illite/muscovite and Kfeldspar adjacent to the lode, along with possible graphitic carbon within 10m. Two zones of intense quartz veining occur, one adjacent to the hanging wall for 12 m and one from 40 m outwards. Quartz vein systems in the country rock are complex and span from pre-schistosity to post-mylonite. They include multiple generations of quartz, actinolite, stilpnomelane, pumpellyite, albite, adularia, chlorites, illite/muscovite, calcite, and scheelite. Metal analyses across the Golden Bar reef showed gold values of 0.13.1 ppm, and low tungsten values, consistent with the observed sporadic scheelite occurrences. As and Sb are at background levels, but enhanced Cr (150 - 430 ppm) relative to the schists (30 - 41 ppm) suggests that the source hydrothermal fluids passed through and leached mafic to ultramafic rocks.

Jan 1, 1994

The Burra Burra Mine is situated in complexly folded Torrensian dolomites and limestones forming the faulted axial region of a major anticline. The orebody mined was largely of secondary origin and confined between two faults, Kingston's on the west and Tinline's on the east. The orebody occurred at the junction between cherty dolomites and a clastic limestone with a large mass of marble breccia along its western margin. Secondary ore consisted of carbonates and oxides in the breccia and the ore bed and detrital copper minerals deposited as part of a clastic breccia in sinkholes and solution cavities in the dolomites and ore beds.Primary sulphides occur disseminated in the marble breccia and in stratiform habit in the ore bed. Kingston's so-called "lode" may be mineralized marble breccia.The marble breccia appears to be of diapiric or sedimentary origin and there is evidence to support a sedimentary origin for some of the copper sulphides. No igneous rocks have been discovered within 20 miles of the mine and any hydrothermal activities were probably at comparatively low temperature. The possibility of extensive stratiform and disseminated copper sulphide mineralization in the marble breccia and ore bed requires testing by further drilling and geophysical surveys.INTRODUCTIONThe re-interpretation of Burra Burra geology and ore formation discussed in this paper resulted from a comprehensive investigation of the mine and its surrounding district begun in December 1961 and in progress at the time of writing. (February 1963). The decision to investigate Burra Burra was taken after a thorough examination of records and reports of all non-ferrous metal deposits throughout South Australia and was given impetus by a report by Thomson (1963) suggesting a sedimentary origin for the copper mineralization. Although the author does not concur fully with Thomson's interpretation there is no doubt that sedimentary processes have played an important part in the formation of the Burra Burra copper deposit, nor is there any doubt that igneous activity played no part.

Jan 1, 1963

By J M. Totterdell

The Permian-Triassic Bowen Basin and the Jurassic-Cretaceous Surat Basin evolved in a backarc tectonic setting behind an active convergent plate margin in eastern Gondwana. Several extensional (Early Permian; Eocene) and contractional (mid-Permian; Early Triassic; Middle-Late Triassic; early Late Cretaceous) intraplate deformational events are recognised in the basins. These can be correlated with similar events in the New England Orogen that was being deformed in the Late Permian-Late Triassic as a foreland thrust belt. The intraplate deformations were probably the consequence of plate interactions, including the accretion of terranes, at the ancient active plate margin, remnants of which now occur in New Zealand.

Jan 1, 1995

Development of Cost-Efficient Environmentally Sound Technology for Enhanced Gold Recovery from Rebellious Gold-Containing Raw Materials Study of biochemical leaching performances in gold-bearing sulfide minerals processing enabled to develop environmentally sound technology of enhanced gold recovery from rebellious gold-containing raw materials. It was found that the ?-10 IMO bacteria activity contributes to increasing system oxygen concentrations and incrementing in rates of oxygen delivery onto surface of gold-bearing minerals. Bacteria activity products, ie, amino acids (?), support the formation of such heterocomplexes as [A-Au-CN]- , providing additional gold recovery into solutions. Technological properties of proposed bacteria solutions were studied. It was found that the proposed bacteria inoculants are capable to growing directly in process of raw materials leaching within a large pH range of media containing cyanides and thiosulfates. They oxidise the sulfur to the sulfate, as well as the antimony (III) and arsenic (III) sulfides to the pentads. For the first time, the hydrophobic cell properties, metabolites emulsifying efficiency, adsorption properties, wetting ability, surface tension and electro-kinetic potential of new bacteria strain solutions were studied as compared with chemical solutions. It was found that the proposed bacteria inoculants reduce surface tension at the solvent-mineral and solvent-concentrate phase boundaries. All aforementioned effects enhance mass transfer processes efficiency. IR-spectroscopy of new bacteria strain culture liquid allowed identifying available amino acids which substantially contribute to heterocomplex anion [A-Au-CN]- formation. Active involvement of heterotrophic bacteria in gold dissolving processes was identified. It was shown that the structure of metals complexes is substantially modified at intensive pulp agitation and during long-term storage. Fractional order reaction in biochemical and chemical gold leaching was identified. It evidences that the gold and impurity metals dissolving processes advance in synchronism. The both processes are running in diffusion zone. Biochemical leaching has advantages over chemical leaching, ie it provides enhanced rates of precious metals dissolving, improved gold recovery by 20 - 30 per cent, decreased cyanide consumption by 50 per cent. At the same time it allows to decontaminate dangerous substances contained in productive solutions produced in rebellious gold-containing raw materials processing. Basic parameters of flotation concentrates leaching by heterotrophic bacteria-assisted processing technology were tried and tested. Technology of gold sorption from leaching solutions was successfully tested.

Sep 13, 2010

By Manca PP, Rossi G, Lipari D, Knissel W, Massacci G, Licheri P, Fioravanti E, Helms W, Lai S

Mining of the massive complex sulphides orebodies of Campo Pisano and San Benedetto (Southern Sardinia, Italy), dates back to before Christ, though their exploitation with modern technology was only resumed in the middle of the last century. The increasingly adverse economic conditions and the weakness of both country rock and mineralization were concurrent in forcing the Company's management to develop suitable high-productivity stoping methods. In the framework of a project fi- nanced in part by the Commission of the European Coranunities, and carried out in cooperation with the Universities of Cagliari (Italy) and Clausthal (Germany), a cemented backfill stoping method was developed. The concrete mix preparation and placement facil- ities, study of the cement mixes and endeavaa-s to optimize the methods are described. The monitoring system for measuring stress evolution within the emplaced backfill is illustrated together with the successful replacement of part of the Portland cement

Jan 1, 1992

By A Romanel, M S. Kato, M P. Piermatei, P Artioli

"Brazil is the sixth worldwide producer of aluminum and Votorantim (Metals) has been operating three bauxite open pit mines in a particular way of working. In those the deposits occur on the top of hills, under forest, coffee, eucalyptus plantation or pasture area.The deposits are not large and normally mining takes an average of two months to be completed before starting the rehabilitation process, which demands a good strategy in mining planning to achieve the production goals.The benefit function developed to select feasible areas uses, beyond production costs, fees from the owner by using their area and rehabilitation cost. Both are based on land use and occupation field survey data. In this process each area with different land use receives a specific rehabilitation cost as input into a block model.Once the selection is made the mining schedule begins, taking into consideration the following premise: the orebody needs to be mined in a short period of time because during this time, the surface owners receive from Votorantim a compensation based on the expected profits from their plantation or pasture, plus royalties related to the ore amount existing in their area.Not all operations have waste dumps. Waste is pushed down by bulldozers to the lower part of the ore border. After loading and transporting ore, the waste is handled back to the mined area to fit the topography. With this step concluded, the mined area is directed to the environmental team who, alongside university partners, develop land reclamation to return them to their owners, eg in 2011, 110 ha were rehabilitated of which 29 per cent is native forest.Votorantim closes many mined areas a year and currently the entire mine planning considers this particular way of operation, making profit with minimum interference with the community and the environment.CITATION:Artioli, P, Kato, M S, Romanel, A and Piermatei, M P, 2012. Environmental variables at bauxite mine, in Proceedings Life-of-Mine 2012 , pp 171-178 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 10, 2012

By Hillis R

As part of BHP Iron Ore's policy and goal of achieving a high standard of environmental management within its operations, a protocol for mine closure has evolved. The need to demonstrate sound environmental management with respect to site decommissioning meant that a comprehensive, environmentally sensitive closure protocol was required. Within this framework, a four-phase protocol was developed, the first phase was the determination of objectives in relation to site rehabilitation and end land use. The second phase was the determination of the process required to achieve these objectives. The third phase was the application of this process in a site specific manner. The fourth and final phase was monitoring of the site with regard to the achievement of determined objectives. The protocol was originally developed to direct the closure and decommissioning of the Goldsworthy site in 1992. This being the first total site decommissioning for BHP Iron Ore. Since that time the protocol has been successfully utilised for the closure of the Yampi (Koolan Island) operations (in 1993/94) and the Shay Gap/Nimingarra Operations (in 1994/95).

Jan 1, 1996

The Australian mining industry can expect to be working internationally competitive high quality coal mines during the twenty-first century. Cost efficient mining methods such as high productivity longwall units with heavy reliance on remote control will be standard and worked by well paid and intensively trained operators. Major changes in mine ventilation engineering can be expected in the use of computers and mine telemetry, the understanding of the mine environment and the frequency of mine disasters, the utilization of mine air contaminants for profitable purposes and the provision of a pleasant and comfortable work environment. New approaches to mine ventilation such as air recirculation will have been considered. There will be an increased need for highly trained ventilation engineers. With the present pace of technological change, quite revolutionary new approaches to mining and ventilation can be expected by the end of the twenty-first century.

Jan 1, 1988

Open cut mining of the Black Rock chalcocite ore started in 1963. A ground movement monitoring programme was commencing in the early stages of mining when signs of instabilityof the western wall became apparent. Eventually 100.000 cu vd, of overburden Were removed beyond the rim of the western wall in an attempt to stabilize the slope. Subsequent decpenlug and mining till the final batter angle of 45 resulted in deterioration and mining was stopped 38 ft short in the ulltimte design deplh of 520 ft.Investigations showed that the geology of the western wall , was a major factor in the instability of this wall. A block jointed model was made 10 illustrate some of the pehomena observed. Quallatative agreement was found between the model deformation and the field measurements obtained.The results of the monitoring programme clearly show the value of this work In respect to the conlrol of the mining operatIon...

Jan 1, 1968

Industrial minerals and rocks are those which are economically important because of desirable physical and/or chemical properties rather than metal or energy content. The evaluation of these resources for investment purposes in general follows established procedures after due consideration of well documented input data. However, in view of the sensitivity of many industrial mineral projects to specific inputs they require very careful analysis. The characteristics of the industrial minerals and the industrial minerals industry are reviewed and the significance of logistics, customer requirements, technology and marketing are discussed. Implications in relation to resources/reserves terminology are considered with phosphate rock used as an example. It is concluded that industrial mineral projects as a consequence of technology and market dependence in particular can give a high level of investment risk. The industry, however, offers most interesting and challenging employment opportunities for geologists, mineral engineers and economists.

Jan 1, 1988

By Hayes K. M, Ostwald J

Compacted tablets of hematite ore (containing clay and quartz gangue) and limestone were heated in air in an ULVAC-RIKO rapid heating furnace to maximum temperatures in the range 1200-1350°C.The resulting sintered products were examined in terms of mineralogy, texture, strength and reducibility. The sintered tablets are a good analogue of normal plant sinters. These investigations have shown that sinters of optimum reducibility are produced in the narrow temperature range 1250-l275°C. Conditions for the production of such highly reducible sinters under plant conditions are discussed.

Jan 1, 1984

By Ellson I. G

Advantage has been taken of the need to build the new mining town of Shay Gap to incorporate a new standard of living in an isolated area, which suffers from climatic extremes. The various problems associated with living in the Pilbara area of Western Australia are outlined, together with their effect on the design of Shay Gap.

Jan 1, 1973

By J Miedecke

A metalliferous mine has operated at Storys Creek from the 1890s to 1979. Storys Creek drains from a pristine catchment and National Park and remains as the most degraded stream from historic mining in north-eastern Tasmania. It has been the subject of public concern since the closure, particularly at times of high rainfall such as existed in 1985 and 1986. The mine is located on the banks of the creek, which flows into a major river, the South Esk River, which is one of TasmaniaÆs largest rivers and important for recreational fishing and water supplies. For much of the life of the of the operations tailings were directly discharged into the creek, and in latter years stockpiled or very close to it. Little rehabilitation was carried out at mine closure. The result was erosion and subsequent deposition on the banks of the creek downstream. Direct emissions of adit water and the consequential emission of contaminated ground water to the creek continue to affect water quality. Contaminant loads discharging from the mine and tailings comprise 70% of the metal load in the catchment and are by far the largest single source. Acidity data suggested that the introduction of systems to introduce alkalinity could be effective in ameliorating the residual acid drainage impacts in the Storys Creek catchment. After a period of investigations and trials which proved their effectiveness, treatments adopted have included the following: relocation of tailings to a constructed and clay capped disposal area and rehabilitation of tailings area; crushed limestone addition to stream flows; crushed limestone addition to creek banks and exposed tailings; sealing of a drainage Adit; and construction of an anoxic drain to generate alkalinity to surface waters draining to old mine workings. These innovative treatments have resulted in a marked improvement in water quality draining from the area. The anoxic drain is believed to be one of the few, if any, which has been constructed to have generated high levels of alkalinity from clean waters and offers a solution to the clogging problems experienced in such drains in the past. Similarly, the use of crushed limestone in an active stream has proved effective in buffering acid drainage and removing metals from solution.

Jan 1, 2003

By McNicol M. D

Petroleum exploration in onshore Gippsland was directed in the 1950s and 1960s towards plays in the basal Latrobe and Strzelecki Groups, but these became forgotten in the 1970s with the Latrobe play discoveries offshore. The principal explorationists of the time were Woodside Oil and Arco Ltd, who then departed the scene after drilling some 18 wells without major success. In the late-1980s successful hydrocarbon finds in equivalent age Otway Group sediments in the Otway Basin were made and in early 1990 Tyers Petroleum began investigations into Strzelecki Group prospects as applied to the onshore Gippsland Basin. Some 18 anticlines have been mapped, based on shallower coal exploration drilling in the Latrobe Group, which from seismic and gravity evidence are believed to unconformably overlie similar anticlinal structures in the underlying Strzelecki Group. Strzelecki targets of interest within drilling depth are the basal Tyers Conglomerate/Rintouls Creek Sandstone Formations which outcrop in the north of the Latrobe Valley and are analogous to the Pretty Hill Sandstone in the Otway Basin. In addition, intra-Strzelecki Group targets similar to Heathfield and Windermere Sandstone Members are also considered to be present. Good source rocks are abundant including coal seams and carbonaceous sediments of Neocomian and Jurassic age, which lie within the oil window. Seal is provided by the overlying Aptian-Albian aged volcanogenic sediments. The Tyers/Rintouls sandstones - a target in the Woodside/Arco wells, with two exceptions, were not reached. Encouraging intra-Strzelecki shows were reported in many of the wells. Basal and intra-Strzelecki porous quartzose sandstones remain one of the few untested plays left in the Gippsland Basin and, in the onshore, merit extra attention as they he within the oil window at economically drillable depths.

Jan 1, 1992

By J Williamson, M Griessmann

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Watershed tungsten deposit is located in the Hodgkinson Province of north Queensland, Australia. The deposit is hosted by Siluro-Devonian flysch-type meta-sediments of the Hodgkinson Formation, which were subjected to four major deformation events. Mineralisation has occurred syn- to post-D4 and is related to the intrusion of S-type granitoids of the Permian Whypalla Supersuite.Watershed is located within a regional NW–SE-striking melange zone composed of brecciated and intermixed arenites and shales. The major NW–SE-striking Tullah fault zone is situated in close proximity to the east of the deposit.The Watershed deposit occurs within a tightly folded upright anticline with NW-plunging fold axis. The anticline contains a major package of coarse-grained to conglomeratic arenite, which harbours the Watershed mineralisation. Several alteration styles occur within the arenites, of which Fe-poor calc-silicate alteration dominated by clinozoisite/epidote is the most significant. Less widespread but locally important alteration styles comprise garnet-dominated calc-silicate alteration, albitisation and sericitisation. The arenites are enveloped by unmineralised carbonaceous shales and shale breccias.Tungsten mineralisation occurs solely as molybdenum-poor scheelite and can be found as three styles: disseminated mineralisation in calc-silicate altered arenites, vein-style mineralisation with quartz-albite-scheelite veins and minor but high-grade mineralisation in albitised felsic dykes.Contact metamorphic rocks and geophysical data indicate the proximity of an underlying granitic body. It is believed that this granitic body was the main driver of the hydrothermal system generating the Watershed deposit. An early mineralisation stage caused the selective calc-silicate alteration of the arenites, while a second stage caused the vein-style high-grade mineralisation. The folded shales enveloping the arenites worked as an effective barrier that kept the mineralising fluids in a confined rock volume.The scheelite mineralisation at Watershed is open to depth, with a granite-hosted porphyry or greisen-style mineralisation anticipated below the current resource.CITATION:Griessmann, M and Williamson, J, 2015. The calc-silicate-hosted Watershed tungsten deposit, far north Queensland, Australia , in Proceedings PACRIM 2015 Congress, pp 545–550 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By S McEachern, J Lowe

An important issue currently facing the mining industry in Australia is the management and cost to the industry and other stakeholders of entry into and exit from towns and their communities. These costs can be environmental, social, economic, political or reputational. The ability of companies to engage the trust of stakeholders, including: communities, governments and investors, is critical, and corporate reputation plays a significant role in this. For the industry to secure a long-term and sustainable future, it must have the technical, business and reputation assets to proceed in a cost-effective, environmentally acceptable and socially supportive way. This research assesses reputation as a critical competitive issue for mining companies, as technology and information make mining more predictable; the physical and human assets of mining companies are less likely to be the critical resource in a Resource Based View model of competitive advantage. The proposition is that in mining today, reputation as it facilitates day-to-day operations, regulatory zeal and access to new mine sites will become the rare, inimitable and valuable resource for mining companies. This paper reports on an ongoing research program to evaluate the impact a mining companyÆs reputation(s), with its various stakeholder groups, has on a companyÆs ability to sustain competitive advantage. Integral to this study is to develop an understanding of the relationships between mining companies and their stakeholders, and the importance of corporate citizenship polices to reputation and hence to corporate sustainability. Through the identification of the drivers of reputation for the various stakeholder groups, a model of reputation formation will be developed and also reputation measures for the mining industry in Australia. The preliminary findings of this research, the results of an industry focus group conducted with representatives from regional mining operations, are reported. The industry focus group was designed to enable a better understanding of who are the main stakeholder groups and how they regard mining companies and to inform the second stage of the research project a Delphi Study of the drivers of reputation by stakeholder groups. The aim of this research is to further the understanding of the relationship between corporate citizenship, reputation and performance in the mining industry, thus assisting companies to strategically manage their corporate citizenship investments.

Jan 1, 2006

By A Hoyle, P Walker, D Bennett

The Phu Kham copper-gold operation located in Laos People’s Democratic Republic (PDR) is owned and operated by Phu Bia Mining Limited. PanAust Limited, based in Brisbane Australia, holds a 90 per cent interest in Phu Bia Mining Limited, with the remaining 10 per cent held by the Government of Laos PDR.The 12Mt/y copper-gold concentrator at Phu Kham commenced production in April 2008. Flotation copper and gold recovery from commissioning was consistently poor, due to the high levels of pyrite and problematic secondary and oxide copper species and non-sulfide gangue.The low recoveries of copper and gold from Phu Kham were recognised during the feasibility study design phase. A bulk sulfide flotation regime in roughing produced high recoveries, however a large capacity cleaning circuit was required and there was risk of not meeting saleable concentrate grade specifications. The installed design offered a capital efficient compromise to ensure that a concentrate grade of 24% copper could be achieved at acceptable recoveries.Incremental improvements in copper recovery were achieved by 2011 through conversion of conditioning cells to flotation cells in both roughing and first cleaning and increased cleaner capacity through the installation of a Jameson cell. In 2012 the Phu Kham Upgrade Project was commissioned to increase mill throughput, along with additional rougher and cleaner capacity to increase residence times at the nominal 16 Mt/y throughput. The marginal reduction in primary grind size due to the additional ball milling power also provided a small recovery improvement.This paper presents the development, design, implementation, and performance of the Increased Recovery Project commissioned in April 2013 which targeted the major causes of copper loss from the circuit. Based on fundamental and detailed test work and mineralogical analysis of concentrator streams, an optimised design was developed which has increased copper and gold recoveries by over 5% and 10% respectively. The Increased Recovery Project has positioned the concentrator to process high pyrite ores that were previously considered untreatable, and opened further opportunities for maximising flotation recovery by de-bottlenecking plant regrind and cleaning capacity.CITATION:Hoyle, A, Bennett, D and Walker, P, 2015. The increased recovery project at the Phu Kham copper-gold operation, Laos PDR, in Proceedings MetPlant 2015, pp 246–265 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

It is indeed a privilege and honour to deliver the keynote address at this 15th APCOM symposium. APCOM has played a significant role in my own career and I am sure in the careers of many of the thousands of other participants over the years since its inception as a short course on "Computers and Computer Applications in the Mineral Industry" at the University of Arizona in 1961. The technical papers and addresses presented at the 14 past symposia provide an imposing record of sustained pro- gress and achievement in the field of computer applications. I will not attempt to analyse this technical side of APCOM but rather endeavour to provide you with a broad popular perspective of the road travelled to date and that lying ahead of us. The name of the series of symposia has changed from time to time, with titles such as Mathematical and Statistical Techniques, Mining and Exploration, and Decision Making being used at various times until in 1972 the name APCOM was coined and the present loga designed by the South African organising committee for the 10th symposium. It can conveniently be accepted as standing for:

Jan 1, 1977