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By K Marler

The Water Act 2000 includes provisions to manage the take of overland flow water. Overland flow water is water that runs across the land after rainfall either before it enters a watercourse, after it leaves a watercourse as floodwater, or after it rises to the surface naturally from underground. To ensure adequate environmental flows and long-term security for water users, it is necessary to balance the amount of water taken as overland flow water and the amount left to flow into watercourses. A water resource plan made under the Water Act 2000 establishes the basis for the sustainable management of this type of water. Of the water resource plans that have been prepared for Queensland catchments, six include provisions to manage the take of overland flow water. This paper discusses some of the common features of these plans and the management approaches adopted. The paper identifies and explains key aspects of the Water Act 2000 framework for managing the take of overland flow water by the mining industry. In particular it explains key concepts of this framework, such as the ability to take overland flow water using existing works, uses of overland flow water that a water resource plan permits, situations where a specific entitlement under the Water Act 2000 is required, and the means for controlling works that take overland flow water. Future initiatives for the regulation and management of overland flow water are then identified and particular challenges for the mining industry associated with using overland flow water highlighted.

Jan 1, 2006

The mining industry continues to faces significant challenges due to increasing resource constraints (quality of ore bodies, water, energy, human resources) and increasing license to operate requirements (safety, health, environment, location) from society, employees and shareholders. Technology advancements and hence research are necessary to ensure that the industry remains viable in this changing environment. Collaborative research is an important part of a company's research portfolio and offers the opportunity for the industry to work on generic issues that it is facing. Obvious benefits include the reduced cost to individual companies by sharing the costs, the opportunity to leverage government funding and the opportunity to conduct longer term projects resulting in skills development (PhD and MSc). Limitations of collaborative research include the reduced focus on company specific issues and the loss of competitive advantage from owning the outcomes of the research. The challenge for researchers and research managers is for them to demonstrate the value derived from longer term, pre-competitive collaborative research. The competitive advantage is not necessarily derived only from the outcomes of the research but rather from the company's ability to direct the research, translate the generic research outcomes to address company specific issues and to implement improvements at its operations. Implementation remains the greatest challenge. In this paper, case studies of selected collaborative research projects are presented to demonstrate key success factors required for implementation of research outcomes. This is an ABSTRACT ONLY. A full-length paper was not prepared for this presentation.

Sep 13, 2010

By Hart G. H

In tectonically disturbed zones within coal seams, decreases in the amount of kaolinite in the cellular structure of inertiniterich coal are accompanied by increasing kaolinite contents in fractures within the coal and/or rocks of immediately overlying horizons. This is due to fracturing of the inertinite microstructure by tectonic disturbance and remobilization and redistribution of free, fine-grained material (kaolinite and/or inertodetrinite.) Ascending waters are believed to transport the kaolinite in suspension, and redeposit it in the fractures and pores in the overlying horizons. This removal of material from the inertinite-rich coal leads to an increase in porosity (higher free gas storage), a presumed reduction in coal strength and an apparent increased proneness to instantaneous outbursts of coal and gas.

Jan 1, 1983

By J C. Koppe, L Vieira

One common problem for blasting in iron ore mines with significant weathering is the occurrence of large blocks of hard rock mixed with softer material. This situation causes a problem for blasting design and sometimes produces large boulders of rock that require a secondary blasting, as well as excavation difficulties. To minimise this situation, geophysical techniques were used to identify the hardest material amid the weathered material. To study the problem, seismic, ground penetrating radar (GPR), electrical resistivity and induced polarisation (IP) methods were used in an intensely weathered Brazilian iron ore deposit. The methods of GPR combined with IP, resistivity and seismic showed to be effective in modelling the contrast among hard, friable materials and soil. The results were used to improve the geological model and create more favourable conditions for the subsequent blast design. The blast design based on geophysical/geological models resulted in significant improvement in the fragmentation of the iron ore. This was achieved by the adoption of a specific drilling pattern for a given geological situation. With the new specialised blasting design the formation of boulders was eliminated.CITATION:Vieira, L and Koppe, J C, 2015. Geophysical techniques applied to blasting design, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 289–294 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

A study of the swelling behaviour of a single batch of high-grade iron ore pellets during hydrogen reduction in a fixed bed showed that the extent of swelling is governed by the nucleation and growth of crystalline iron protuberances from the wüstite grains. Over the reduction temperature range 650 to 1000°C, it was found that substantial degrees of swelling can occur at temperatures in excess of 850°C, and significant variations in the swelling behaviour of individual pellets from different bed levels are observed under these conditions.The results are discussed in terms of a recent swelling theory and shown to be in general agreement.

Jan 1, 1978

By S C. Dominy

Various styles of gold mineralisation pose problems during sampling because of their complex gold grade distribution and presence of coarse gold. Effective sampling and sample preparation forms the basis of resource estimates. The design of a sampling and assaying protocol must be based on a thorough understanding of the mineralisation in question, which should include consideration of gold particle size and mass distribution. The proportion of coarse gold within samples has a profound effect on the requirements for sample preparation and assaying. Choice of preparation procedure and assay type is of critical importance if sampling errors are to be minimised. Traditional fire assays, using small charge sizes, often understate assays gained from large charge sizes and techniques such as screen fire assay and LeachWELL. Proper application of the Theory of Sampling reduces errors during collection, preparation and assaying. A quality control/quality assurance program must be implemented and critically assessed. A case study from the Ballarat mine is presented, which is characterised by substantial quantities of coarse-gold hosted in quartz veins. Diamond core drilling is the key input into resource delineation. A number of different sampling and assay options have been trialled over the recent project history. The current sampling protocol utilises whole drill core, using LeachWELL assays after logging and photography.CITATION:Dominy, S C, 2017. Sampling coarse gold-bearing mineralisation – developing effective protocols and a case study from the Ballarat mine, Australia, in Proceedings Eighth World Conference on Sampling and Blending , pp 71–84 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

Bauxitic laterite of variable thickness and grade is best developed in the Darling Range but covers a large part of the southwest corner of Western Australia. Its limits are defined by the rainfall isohyets to which jarrah forest is confined. Within this broad belt there is an increase in arable land southwards concomitant with a thinning of the laterite layer.Bauxite quality and perhaps thickness as well are dependent on the type of source rock, and are influenced by topography. Economic deposits occur over a vertical range in altitude of about 1200 ft. Some bauxite orebodies appear shoot-like in character, and analogy is suggested with the ore shoots of syngenetic metalliferous deposits.The alumina is in the form of gibbsite enabling low temperature digestion in treatment.INTRODUCTIONAlthough the existence of bauxite in Australia has been known for many years it is only recently that exploitation has commenced of the two most important deposits, strangely at almost diagonally opposite tips of the continent (Fig. 1).Recognition of the importance of the bauxite in the southwest corner came about initially through the efforts of Western Aluminium N.L. which, with some outside financial help, tackled the early exploration with commendable foresight and courage. Subsequent investigations around the periphery of the original reserves (now held by Alcoa of Australia) were undertaken by several companies, including Bauxite Exploration Pty. Ltd.ORIGIN OF BAUXITEThe genesis of bauxite is stilI somewhat controversial.Owing to its common association with kaolin some investigators have been led to believe that it has been derived from the latter; others believe the process has been vice versa.From a recent study of the Arkansas bauxite region in the...

Jan 1, 1964

By Edwards A. B

A suite of specimens from the newly developed Black Star copper ore body at Mount Isa was made available for mineragraphic study by the Mount Isa Mines, Ltd. The specimens were selected as representative of the different phases of mineralisation found in the ore body, rather than with a view to furnishing a complete cross-section of it; and the examination has been carried out with a view to ascertaining (1) the nature, extent and association of the arsenic, antimony and possibly bismuth, minerals in the ore, (2) the mode of occurrence of silver in the ore, and (3) whether galena and sphalerite occur in minute forms well below the sIzes readily observed in hand specimens.Analyses of the January to June, 1944, mill head composites show that the proportions of the elements Ag, As, Sb and Bi in the ore are as follows:Ag 0.000013 = 0.35 oz./tonAs 0.024Sb 0:002Bi 0.0005The copper content of the mill heads ranges from 3.5% to 4.75%, the lead content from 0.03% to 0.08,% and the zinc content from 0.09% to 0.23%.MINERAL COMPOSITIONThe specimens range from massive sulphide ore, consisting of areas of chalcopyrite, pyrrhotite, and rarely sphalerite, from 1 to 3 cm. across, to fragments of extremely finely banded pyritic shale in which no minerals other than pyrite are visible. The gangue associated with the massive sulphides is chiefly dolomite, and sometimes white quartz. The pyritic shale fragments show evidence of shearing and faulting on a micro-scale, the fractures sometimes being filled with sulphides and vein minerals.The ore minerals found in the polished sections are pyrite, arsenopyrite, marcasite, sphalerite, chalcopyrite, valleriite, chalcostibite, galena, dyscrasite, jamesonite, magnetite, gold, graphite and rutile.Pyrite (FeS2)Pyrite occurs chiefly in two forms according to whether deposition took place along the bedding planes or along the intersecting faults and fractures. Deposition of pyrite along the bedding planes of dense, thinly banded shales ha,s produced a metasomatically altered shale in which the pyritic bands are from 0.02 to 0.03 mm. wide, and alternate with bands...

Jan 1, 1945

By P Mulvey

"Currently mine process studies and geochemical waste characterisation are considered as two interdependent studies, necessary for the development of the mine and inclusion in the environmental impact statement (EIS). Geochemical waste characterisation will utilise the simulated tailings produced by the mine process studies team to understand the behaviour of the tailings, but the two teams rarely integrate these to develop a coherent and agreed final design.Thorough mine waste geochemical assessments can develop processes to minimise environmental harm, resulting in substantial savings in the decommissioning, closure and rehabilitation phases, and may also be able to address changes in mineral processing methods that can result in substantial savings in process inputs, or even recovery of metal concentrates.Based on geochemical waste characterisation, the full cost of waste management can be calculated and incorporated into the costing of milling.  This allows for a more effective evaluation of the metallurgy.  A number of examples are presented in which substantial improvements have been made from the collaboration of both the metallurgical and geochemical teams during planning and the metallurgical team and environmental team during operations.*This paper is only available for individual download. It is not included in the conference proceedings*CITATION:Mulvey, P, 2013. Optimising metallurgy at the planning stage to minimise environmental impact - a feedback loop from geochemical waste characterisation, presented to MetPlant 2013 Conference (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

By B Mobilio, G B. Sharrock, J L. Lett, I Brunton, T Thornhill

Full-scale marker experiments at Cadia Valley underground operations have been ongoing for over 14 years. Initial marker experiments were undertaken in the Ridgeway sublevel cave (RW) (2002), and subsequently at Ridgeway Deeps (RWD) (2008) and Cadia East PC1 (CEPC1) (2012) block caves. Over 25 000 markers have been installed at the three caving operations to date (approximately 20 000, 3000 and 2500 for RW, RWD and CEPC1 respectively). These experiments aimed to quantify and assess the geometry of the extraction zone, development of the extraction zone over time, variability of flow behaviour and factors affecting flow behaviour in both the near and far field cave column. This paper discusses marker recovery results from the RWD and CEPC1 caves.With respect to the two cave operations, marker recovery in both the near field (markers recovered vertically within 70 m of the extraction level) and far field (markers recovered vertically above 70 m of the extraction level) indicates disturbed flow behaviour where marker recovery is not spatially uniform during material extraction. Two distinct patterns or transient behaviours in the extraction zone are indicated. For RWD (advanced undercut), early material recovery was close to the major apex, and expanded towards the centre of the drawbell as more material was extracted. The inverse was observed for CEPC1 (post undercut), where recovery occurred in the centre of the drawbell initially, and expanded outwards towards the major apex. This trend of recovery for the two operations continued in the far field. In the region above the major apex, recovery was observed for all heights, with no clear height of interaction zone (HIZ) indicated. All of these behaviours significantly deviate from both conventional ellipsoidal flow theory and Laubscher’s (2000) design guidelines. For this reason these new mechanisms are termed the Disturbed Extraction Zone (DEZ).For the CEPC1 marker experiment, electronic markers were utilised to investigate the vector movement of material in the near field. Marker recovery movement vectors in the near field indicate extraction zone widths in the order 30 m, with localised marker recovery outside this region (significant horizontal movement of material potentially due to cave muck pile rilling and blast burden movement). Analysis is ongoing for far field marker vector movement, and will be reported once additional marker recovery has been obtained.CITATION:Brunton, I, Lett, J L, Sharrock, G B, Thornhill, T and Mobilio, B, 2016. Full-scale flow marker experiments at the Ridgeway Deeps and Cadia East cave operations, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 141–150 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By M I. Pownceby, N A. S Webster, J Manuel, N Ware

The properties of iron ore sinter – commonly defined by measures of tumble strength, reduction degradation and reducibility – have a major impact on blast furnace performance. These properties are largely influenced by raw material properties, in particular the bulk ore composition. Despite this importance, there is a lack of quantitative data on the impact of ore chemical composition on iron ore sintering. This is surprising since the levels of Fe, SiO2, Al2O3, P, MgO and other elements, together with the nature of the minerals in the fine ore, play a major role in determining the abundance and type of high-temperature bonding phases that form during sintering. It is the abundance and nature of the high-temperature bonding phase(s) that directly influences sinter quality. This study combines in situ diffraction experiments in model sinter systems with laboratory-based compact sinter tests using natural ores to examine the links between iron ore composition and sintering temperature and their effects on standard metallurgical sinter quality test methods. Results help to establish the critical compositional and thermal parameters that control the bonding phase chemistry, which in turn influences the physical characteristics of the sinter matrix. This information should enable operators to predict optimum sinter operating conditions based on the initial chemistry and mineralogy of the iron ore fines and recognise the chemical modifications to the original iron ore fines required to produce high-quality iron ore sinter.CITATION:Pownceby, M I, Webster, N A S, Manuel, J and Ware, N, 2015. Iron ore geometallurgy – examining the influence of ore composition on sinter phase mineralogy and sinter strength, in Proceedings Iron Ore 2015, pp 579–586 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By H Indirawati, R Ayres, A Nur Kasnanto, S Konopa

As a project moves through the mine life cycle, the quantity of data available increases and the understanding of the orebody matures. Incorporating new information quickly and efficiently in current 3D models, is essential for adding value across the life-of-mine value chain. At the Martabe Gold Mine, the resource development group manages 14 drill rigs on six resource projects, including three operating mines. The Martabe deposits are geologically complex and the volume of new information that becomes available each day is substantial. It is imperative that new geological and assay information is integrated into the 3D models as soon as possible, so that drill planning and targeting can be modified accordingly. Martabe uses Leapfrog<sup>®</sup> 3D software to update and interrogate the 3D models on a dynamic basis as data becomes available. This results in faster and more effective changes to drill planning and schedules. The impact of this is better drill productivity and cost savings due to optimal drill targeting, and availability of up-to-date models incorporating the most current data. CITATION: Konopa, S, Ayres, R, Nur Kasnanto, A and Indirawati, H, 2018. Optimised drill targeting using dynamic 3D modelling, Martabe Gold Mine, Indonesia, in Proceedings Complex Orebodies Conference 2018, pp 99–101 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By W B. Edgar, I M. Platten, C A. J Towsey, B W. Cuffley

The evaluation of historical goldfields has been common over the past 15 years, reflecting changing economic conditions, improvements in knowledge and technology and lack of greenfield sites. Many goldfields comprise narrow gold-quartz veins, which are structurally complex with an irregular distribution of gold, have variable geometry and architecture and display late deformational effects. The study of historical mine records can be an important tool during early and advanced project evaluation, since it contributes to understanding the orebody, exploration target size and setting expectations. Mine records include documents such as plans, sections, reports, news cuttings, production tabulations, etc. A major advantage for the modern explorer is the capability of computer modelling to display this data in 3D. Historical records can give the explorer substantial information on various deposit characteristics, not least grade and geological continuity, geometry and architecture, mineralogy, metallurgical properties, bulk density and ground conditions. From an evaluation perspective, historical records can be used to support a Mineral Resource estimate, though its application will depend upon the quality and quantity of the data and judgement of the Competent Person. Effectively used, historical records can reduce geological uncertainty and focus evaluation efforts û thus reducing project risk.

Jan 1, 2009

By M Lentz

This paper will discuss the issues associated with blasting in an urban mining environment that have been addressed by Winstone Aggregates at the Mt Wellington Quarry. These issues include - control of vibration and air overpressure, repeatability of shot performance, fragmentation on an extremely low maximum instantaneous charge, compliance with Territorial Authority regulations and perception. Over the last two years, in order to address these issues, Winstone Aggregates have undertaken a programme of continuous improvement, which has included; ò implementation of new technology; ò revising site procedures; ò conducting an investigation into the structural response of local buildings; ò investigating safe extrapolation; ò extensive public consultation; ò establishing credibility during the consent process; ò identification of perception issues; and ò building relationships and trust with neighbours. The issues addressed at the Mt Wellington Quarry have increasing significance for traditionally rural mining operations, as the input of the local community being urban or rural, increases. New and existing operations have the potential to adopt best practice now, building trust with the community and raising the profile of the industry.  

Jan 1, 1999

By Beardsmore G. R

Geothermal gradients in the Gippsland Basin commonly exceed 35¦ C/km. Consequently models of thermal maturation may indicate exploration targets with an anomalous age/depth distribution. However regional geothermal models are constrained primarily by observations of surface heat flow. High geothermal gradients may simply reflect the presence of low conductivity coal beds within the basin. Heat flow data are not readily available for the Gippsland Basin. Normally special purpose drill holes are required to provide direct determinations of surface heat flow. These provide core samples for thermal conductivity and allow measurements of a stable geothermal gradient at least one year after drilling. Different indirect procedures are now required to provide estimates for the Gippsland Basin. Bottom hole temperatures can be used with suitable corrections to provide an indication of the regional geothermal gradient. However the corresponding thermal conductivities are more difficult to determine. Geophysical logs can be used to detect the major lithologies but detailed statistical analysis is required for numerical estimates. Complex mixing models are now suggested for geothermal surveys linking physical properties to variations in the mineralogy of each well. Allowing for low conductivity coal measures the data in the Gippsland Basin suggest values for heat flow consistent with regional trends in Australia. Interpretation is complicated by overprinting of transient thermal events with different time scales. Apart from the tectonics of basin evolution geothermal signatures may be complicated by regional ground water migration, the 'hot spot' trace associated with southward younging of Cainozoic volcanism, diagenesis, and basin refraction.

Jan 1, 1992

By Benkendorff P. N

Cement production in Australia approximates 6.5 million tonnes per year. Cement clinker is sourced from 15 plants which operate 28 kilns. Cement grinding is conducted at 14 of the clinker plants plus 7 grinding plants. Average annual capacity per kiln or plant is lower than in many overseas countries, but kilns introduced since 1970's have been of larger size more in keeping with size trends overseas, although still smaller than the large units overseas. Substantial economies in capital and labour costs can be achieved in large production units, particularly with dry process kilns using precalcination techniques in which part of the fuel is introduced in the static preheater section ahead of the kiln while the balance is added to the kiln in a conventional manner. Precalcination techniques have been introduced to the Australian cement industry but as cement transport costs form a major part of supplying diverse market areas, the size of kilns is likely to remain less than maximum owing to balance with distribution costs. The cement industry uses significant amounts of thermal and electrical energy which can be minimised by proper selection of equipment and technology. Labour costs are also significant and can be contained by automation and computer control of the process.

Jan 1, 1989

Copper waste dump leaching is growing in importance because of the.large tonnages (up to 250,000 ton/day) of low grade waste rock available from open cut mining of copper deposits and proof that controlled leaching of copper from such dumps can be profitable.Overburden or waste rock, ranging in size from large boulders to fines, is dumped as cheaply as possible on sloping sites. Copper is leached from the dumps by applying up to 12,000 gal/min of leach solution (a combination of spent solution from cementation and make-up water) to the top of the dumps by various techniques.Efliuent from the dumps is sent to a cementation plant for copper recovery.Factors which may be controlled, either directly or indirectly, to give a controlled copper content in the dump efliuent (usually 1-2 g/l.) are the cycle of operations (i.e. the alternate wetting and drying periods), thevolume of solution applied to the dump, pH, Fe2+ and Fe3+ content or redox potential, oxygen content, bacteria and their necessary nutrients, and temperature.Dissolution of oxide copper minerals appears to be mainly a function of acid concentration. Copper sulphide minerals need oxidation for dissolution to occur and this is accomplished by a combination of oxygen,ferric ion, and bacteria. Oxidation of pyrite, oxidation of Fe2+ to Fe3 +, and hydrolysis of Fe3+ are of some importance in leaching practice. The presence of gangue carbonate minerals is detrimental.Physical factors connected with penetration of solution into large rocks are important and the treatment of an individual dump usually extends over a period of many years. Recovery of copper from solution is usually achieved by cementation with iron (usually in the form of crumpled cans) but the use of sponge iron is becoming more important. Iron consumption varies from 1 to 4 lbiron per pound of copper. Preconcentration of the copper in the efliuent solution by solvent extraction followed by electrolysis may become a useful method.Application of dump leaching techniques to metals other than copper depends on finding an economic method of recovering the metal from solution...

Jan 1, 1967

The JORC Code, which has been in existence as a Code incorporated in the listing rules of the Australian Stock Exchange and New Zealand Stock Exchange since 1989 and 1992 respectively, has been revised and will be re-released in 2003. This revision followed a call for submissions in December 2001, the publication of an exposure draft in late-2002 and an exposure period during which a large number of constructive comments were received. These comments were reviewed and a further exposure draft released as part of the current exposure draft of the ASX listing rules. It is anticipated that the final Code will be incorporated into the stock exchanges listing rules in late-2003. The 1999 JORC Code has been the standard on which other reporting Codes have been based, each of which has contained refinements. Three in particular, the Reporting Code from the United Kingdom/Ireland/Western Europe, the new Canadian Reporting standards and the SAMREC Code from South Africa, influenced JORC in the preparation of the 2003 JORC Code. Whilst there are differences between the 1999 Code and the 2003 Code, these changes are mainly in the guidelines. The Code definitions, which are largely in accord with agreed international definitions, remain substantially unchanged. The two main changes in the 2003 Code are the requirement for a Competent Person to be responsible for the documentation relating to the reporting of Exploration Results, and the introduction of æRecognised Overseas Professional OrganisationsÆ as overseas organisations to which Competent Persons may belong. Other changes include: clarification of the reporting of exploration targets or potential; the rearrangement of the diamond reporting clauses; the introduction of guidelines for the reporting of Industrial Minerals; modification of the coal clauses and recognition of the new Coal Guidelines; and the introduction of a guideline encouraging the discussion of relative accuracy and confidence in resource/reserve estimates. Other lesser changes to the Code are listed and discussed briefly. The release of the 2003 JORC Code maintains the standard set by JORC as a world leader in the development of mineral reporting Codes and their adoption by industry.

Jan 1, 2003

By T P. Fischer, S N. Williams, N C. Sturchio

Chemical and isotopic analyses of fumarole gases from Galeras Volcano, Colombia provide significant insights into the origin of volatile components in the magma. Water comprises a mixture of magmatic (rock-equilibrated at high temperature) and meteoric, with the relative proportions varying through time. Carbon isotopes are most consistent with a mantle source, although other contributions to the system cannot be ruled out. Nitrogen most likely originated from organic matter in subducted oceanic sediments. All of these 'primary' components have been modified somewhat by interaction or exchange with other reservoirs during ascent to the surface. In addition to information on the origin of the gases, these data show significant temporal variations precursory to eruptive events. Chemical ratios change and water becomes more meteoric in character prior to eruptions.

Jan 1, 1995

By V N. Rudashevsky, F Melcher, J Lodziak, D Klosa, N S. Rudashevsky, M Sitnikova, L Gast

A combination of novel and æclassicÆ methods, namely electric pulse disaggregation (EPD), hydroseparation (HS), preparation of monolayer polished sections, and mineral liberation analysis (MLA) was employed to study ores from platinum pipes (Bushveld Complex, South Africa), pristine PGE mineralisation of the Main Sulfide Zone (Great Dyke, Zimbabwe), as well as ancient and modern gold/PGM placer deposits. It is shown here that the EPD technique liberates mineral grains of interest without any visible destruction allowing the study and analysis of individual rock-forming and ore minerals, in our case especially platinum-group minerals. The HS method is an effective tool in concentrating heavy minerals by factors up to 10 000 fold. As near-total recovery of grains >10 ¦m is achieved, the nugget effect can be overcome also in case of limited availability of samples (drill core, museum specimens). The MLA technique is a fast tool to detect and characterise mineral phases in ores and ore processing products. Many mineralogical parameters of individual grains and mineral assemblages can be deducted and documented. The results show that the techniques employed, either on their own or in combination, provide a wide range of additional information especially on platinum ores which is beneficial to both the researcher and the metallurgist.

Jan 1, 2008