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By A I M Ritchie

The pyrite oxidation rate is a process central to both the performance of bio-oxidation heaps, used in the pre-treatment of some refractory gold ores, and to the levels of pollution in acid rock drainage (ARD) from pyritic waste rock dumps. A goal in bio-oxidation heaps is to achieve high oxidation rates in the heap as a whole. In comparison, one way to mitigate the environment impact of ARD, is to reduce the overall oxidation rate in the waste rock dump since pyrite oxidation is the primary pollutant generation process. In both bio-oxidation heaps and waste rock dumps the overall oxidation rate of the pyritic material (the intrinsic oxidation rate) at these sites. Much research has been conducted over the last 40 years or so on the oxidation rate of pyritic material with particular emphasis on the catalytic role played by bacteria. More recently mathematical models and field measurements have clarified the extent to which oxygen transport rates are rate limiting, what the dominant oxygen transport mechanisms are and the physical properties of the heaps which have most impact on these transport rates and on the overall oxidation rate. How the performance of bio-oxidation heaps can be optimised and how the pollution load in drainage from waste rock dumps depends on gas transport mechanisms is briefly reviewed. The sensitive of the overall oxidation rate in bio-oxidation heaps and waste rock dumps to details of the intrinsic oxidation rate is quantified.

Jan 1, 1994

The major technological advances of the last 30 years have profoundly reshaped mining practices. Machines keep getting bigger while productivity continues to increase and manning levels drop. These trends will continue and the introduction of breakthrough technologies will continue to accelerate, driven by a continued focus on lowering the cost of production, improving the productivity of workers and machines, and ensuring safer working environments. At the same time, global consolidation of mining companies has impacted on technology development in a range of ways. There are many potential technologies being proposed, some already operating in Australian mines. The automation of underground load-haul-dump (LHD) trucks for example, continues the process of removing workers from the most dangerous operating environments. Global positioning systems fitted to draglines, fibre optic communication channels, and 400 tonne trucks are only some examples of what lies ahead. However, where we need to return focus is to the technology of management û which is also one of the two key interrelated themes of this keynote address. Have we, as an industry, adequately been able to keep up with technological advances? Are our management systems as competent as the machinery we employ? The other key theme is the processes of globalisation and consolidation. What are the impacts on our industry? What are the implications of these processes, particularly for the ways in which we manage our people? My paper is divided into several components:some comments on the coal industry and the dramatic restructuring we have seen in recent years; in the context of this restructuring, an overview of my company and its evolution; my views on the role of contractors; some comments on the consolidation also occurring in the mining machinery and equipment, technology and services sectors; some observations on two major areas of technology û drill and blast; and trucks, shovels and excavators; the implications of consolidation and new technology for our employees and management; and finally some comments on research programs.

Jan 1, 2001

By A Giyose, V Malysiak, K Davey

Batch flotation tests were conducted on a haematite-bearing Sishen iron ore slimes sample from South Africa using reverse cationic flotation. The effect of grinding on flotation performance, the flotation response of various key impurities in the sample, and the feasibility of increasing metal recovery by refloating tailings in a scavenger flotation step were investigated. The test results indicate that reverse cationic flotation is effective in rejecting impurities from the iron ore sample tested. From a head grade assaying 6.4 per cent SiO2, 2.14 per cent Al2O3, 0.402 per cent K2O, 0.082 per cent P and 0.194 per cent TiO2, the levels of impurities were reduced to 1.83 per cent SiO2, 0.88 per cent Al2O3, 0.095 per cent K2O, 0.066 per cent P and 0.174 per cent TiO2 in the final concentrate at a Fe recovery of 74 per cent. The flotation response of SiO2, Al2O3 and K2O were found to be better than that of P and TiO2. The testwork demonstrated that grinding to 80 per cent passing about 49 microns is essential for upgrading the Sishen iron ore to produce >67 per cent Fe concentrate grade. This grind size corresponds to about 80 per cent liberation of haematite from the gangue minerals. Fe recoveries up to 76 per cent were obtained by refloating the rougher tailings in a scavenger stage, with little effect on the final concentrate grade. Size-by-size Fe recovery data obtained indicated that particles below ten microns were mostly lost in the desliming stage conducted prior to flotation whilst some reported to the froth by entrainment. Some of the coarser haematite-gangue composite particles reported to the froth product by genuine flotation.

Jan 1, 2009

By Pati±o A

The Argentine pyroclastic loess arevulcanogenic deposits, which have their sources in the circumnpacific rim. The object of this work is to realize a de-tailed mineralogical characterization of this sediments, to use it like a geo logic outline which regiters discordance or similarity in them, The sampling zone extend from 714N-4125 to 622W-339S. The descriptions of these sediments was considered like basic, mesobasic or acid rocks. The basic sediments, looking like andesite-basaltic composition, are fill-ing the andean valley. The mesobasic one have a similar composition with a pyro-clastic dacite rock, and have been found in marshy pleistocene sediments in the intermountain valley and in the pampeana prairies. The acid ashed conform rhyoda-cite-rhyolite sediments which form the pampeana loess covers in the prairie.

Jan 1, 1990

By G Chen

Magnesite and dolomite are two salt-type minerals. The surface characteristics of these two minerals are almost the same. It is very difficult to remove dolomite from magnesite ores by flotation process. The present study was performed to develop a new collector and a better flotation scheme for magnesite from dolomite. The flotation tests show that there exists a significant difference in flotability between magnesite and dolomite when dodecyl phosphate synthesised with dodecanol, phosphorus oxychloride and other chemicals is used as collector. Sodium silicate was used as the modifier to improve flotation selectivity. It was found that sodium silicate selectively depressed magnesite at pH 4.5 - 7.5. The separation of magnesite from dolomite was achieved in a reverse flotation which resulted in a 76.1 per cent yield of magnesite with a grade of 47.3 per cent at 100 ppm dodecyl phosphate and 75 ppm sodium silicate. The flotation mechanism was investigated by characterising surface electrical properties and measuring the adsorption density of the reagents on magnesite and dolomite.

Jan 1, 2005

By K Ehrig, C Lower, V Liebezeit, M Smith, E Macmillan

"Minerals, minerals, minerals. Elements occur in the earth as minerals. If local physical, chemical and structural conditions are conducive to concentrating these minerals to sufficiently high abundances in the earth’s crust, a mineral deposit will form. If technology is available to extract metals from the minerals economically, then you have a mineral resource that will be mined and processed. Determining which minerals are present and quantifying their abundances, textural characteristics (grain size and shape) and how they are intergrown with each other is the realm of the mineralogist. Geologists use this mineralogical data to understand how the mineral deposit formed, how to find high-grade zones within the deposit and where to find other mineral deposits. Metallurgists use this data to design, operate and optimise processing facilities to extract metals from the minerals. The types, quantity and precision/resolution of the mineralogical data required by geologists and metallurgists are different, but are not mutually exclusive of each other. Fortunately, measurement technology is available that is relatively rapid, high volume and low cost, thus enabling ore and gangue mineral characterisation at a historically unprecedented scale of a mineral resource.CITATION:Ehrig, K, Liebezeit, V, Smith, M, Macmillan, E and Lower, C, 2014. Geologists and the value chain – how material characterisation by modern mineralogy can optimise design and operation of processing facilities, in Proceedings Ninth International Mining Geology Conference 2014, pp 5–14 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 18, 2014

By S Jahanshahi

In an earlier LCA study, the authors showed that the electricity consumption of the electric furnaces used in the production of the ferronickel and ferrochrome feedstocks made significant contributions towards the Gross Energy Requirement (GER) of stainless steel production, on a æcradle-to-gateÆ basis. Given the relatively low efficiencies associated with electrical power generation, substantial reductions in the GER for stainless steel production could be anticipated if more direct use of thermal energy was made in the ferronickel and ferrochromium smelting stages.In view of these findings, a follow-up study was undertaken to investigate the likely environmental benefits of using bath smelting processes for the production of ferronickel and ferrochromium compared to the traditional rotary kiln-electric furnace processes, but still utilising the electric furnace process for stainless steel production. The METSIM process simulation software package was used to set up models of the two bath smelting processes and provide process energy requirements that were incorporated into the LCA. The environmental impacts considered in the LCA were greenhouse (Global Warming Potential, GWP) and acid rain gas (Acidification Potential, AP) emissions and solid waste emissions.The results of the study showed that the bath smelting route reduced the GER for ferronickel production by about 37 per cent over the traditional route, which translated to about a 21 per cent reduction in the GER for stainless steel. The corresponding reduction for ferrochromium was about half that for ferronickel, and when combined with the ferronickel result gave a 25 per cent reduction in the GER for stainless steel production. Similar reductions were also observed for the GWP and to a lesser extent the AP for both feedstocks, as all primary energy inputs were essentially fossil fuel based. Substantial reductions in solid waste emissions were also indicated for the direct use of ores in smelting. By utilising bath smelting processes for the production of the ferronickel and ferrochromium feedstocks, stainless steelÆs suitability for meeting many of the goals necessary for sustainable development, already recognised because of its particular properties, would be even further enhanced.

Jan 1, 2004

By V Mutton, L Potts, D Joyce

This paper describes the method of extracting sill pillars within the underground operation from under unconsolidated mullock fill at the Cracow Gold Mine. This pillar recovery method was initially successfully used to recover sill pillars at Crusader Mine, Western Australia in 2001. Globally significant resources have been sterilised due to the placement of loose rock fill above crown pillars and within adjacent stopes. The method described here offers significant opportunities to increase recovery of sill pillar recoveries.The royal orebody sill pillars at Cracow Gold Mine form a significant resource. Extraction of these pillars needed to be undertaken with minimal ore dilution and maximum ore recovery. The application that was selected to consolidate the loose mullock fill above each pillar used an injection grouting process (Minova FB200).Cracow Gold Mine mining method is bottom up bench mining. The pillars were left within the orebody to allow for stoping to commence whilst the decline was being developed. Due to the remainder of the orebody being extracted the only access to consolidate the backfill was from the sill pillar extraction level. Numerous problems were encountered and overcome from product selection and trial, system of injection to extraction.This pillar recovery process achieved a 95 per cent recovery of the sill pillar compared with an estimated 60 per cent typical for other mining options.CITATION:Potts, L, Mutton, V and Joyce, D, 2012. Pillar recovery at Cracow gold mine using grouted consolidated mullock, in Proceedings Narrow Vein Mining 2012 , pp 179-184 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

By M Lynch, B White

The historic city of Charters Towers in North Queensland is underlain by an extensive labyrinth of old mine workings in a large number of flat lying, subparallel, main and cross-cutting cross reefs extending of the order of 5 km along strike and down to a depth of 700 m in parts. These old workings produced over 6.6 million ounces of gold at a grade of over one ounce to the tonne prior to closure in 1920.Citigold is progressing the development of a modern, high productivity, low cost new mine to extract extensions of these reefs as well as other as yet un-mined reefs. To do this it is changing the paradigm for operating in such circumstances. This paper first briefly reviews the setting for the development and then discusses the philosophies and concepts that Citigold is proposing to use, harnessing technology to create a mine that exemplifies more productive and safer mining based on operating in the digital age.The paper addresses how a modern approach is being applied to the planning of a mechanised, deep, narrow vein, hard rock gold mine under a city. It also describes briefly the successful æexperimentationÆ with longhole open stoping methods developed at the companyÆs small underground operation (the Imperial Mine) to the south of the city, which will also be expanded substantially as part of the Charters Towers Gold Project.The paper also addresses the development of new and/or modified technologies in the venture, with the objective of pursuing continuous and autonomous mining methods. The company is adopting a holistic systems approach, addressing people, process and technology in order to efficiently identify and locate the high-grade ore zones and then extract them effectively at a high grade by minimising waste development and haulage, dilution and energy consumption, and with minimal environmental impact.CITATION:Lynch, M and White, B, 2013. Brave new world autonomous mining systems, in Proceedings World Gold 2013 , pp 157-166 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By S Girard, L Rowland, V Lawson, Y Shields

Since 1948, ValeÆs Matte Separation Plant has been successfully using magnetic separation and froth flotation to separate the copper sulfide, nickel sulfide and Ni-Cu metallic alloy contained in Bessemer matte for downstream processing. Though some equipment upgrades have been performed over the years, the flow sheet has generally remained unchanged since the early 1970s. The need to improve metallurgical performance led to the trial of a scalping flotation column to produce a final copper concentrate ahead of the cleaner circuit feed to take advantage of a high degree of copper mineral liberation, reduce cleaner-recleaner circulating loads and decrease the associated loss of selectivity. Plant results indicated that 50 per cent of copper contained in the rougher concentrate could be recovered at final grade target. Results indicate that up to a 1.5 per cent increase in copper recovery to copper concentrate was achieved during the scalper trial due to a reduction in the generation of fine chalcocite which has historically been observed to report to flotation tailings due to surface contamination. Deficiencies are currently being addressed and a long-term trial is scheduled to confirm the benefits of copper scalping.CITATION:Girard, S, Rowland, L, Shields, Y and Lawson, V, 2012. Copper scalping at ValeÆs matte separation plant, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 299-308 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By K J. Davey, J T. Woodcock

Australian steelmakers produce up to 30 000 t/yr of electric arc furnace (EAF) dust. Current disposal techniques include sending EAF dust to landfill, stockpiling, and paying zinc smelters or registered waste removalists/processors to take the dust. Many of the complex overseas pyrometallurgical and hydrometallurgical treatment routes cited in the literature are not considered economic. Governmental, environmental and social pressures on producers to consider more sustainable disposal options are mounting, and there is now a strong push to consider recovering potentially valuable or recyclable components, such as zinc and iron units, from EAF dust. As well, there remain strong economic drivers for producers to find lower cost disposal solutions. Characterisation studies undertaken at CSIRO Minerals have revealed important physical differences in the nature of the zinc- and iron-bearing phases contained in domestic EAF dusts. These differences have been exploited using simple and cheap mineral processing techniques such as water washing, wet cycloning and wet magnetic separation. This has allowed a significant upgrade in the zinc content of EAF dust to be achieved, together with a reduction in the levels of key smelter penalty elements, such as chlorides and fluorides. The zinc-rich portion of the dust is now a more attractive smelter feed while the iron-rich part of the dust could potentially be briquetted or pelletised with a reductant and recycled to recover iron, and thus close the loop on dust processing. The basis of the separations tested together with laboratory results from several Australian dust samples are presented and discussed in this paper.

Jan 1, 2006

Cretaceous volcanic activity (Hauterivian Albian) in the Peruvian Andes can be found along the coast of Peru and the western edge of the Andes mountains between 15o30'S and 5o30'S, extending discontinuously in south to Chile and north to Ecuador and Colombia. This volcanic activity formed in three aborted marginal basins; the NNW-trending volcanic Ca±ete and Huarmey, and NNE-trending Lancones basins. These volcanic rocks are predominantly andesitic and basaltic in composition, of calc-alkaline and tholeiite affinity with subordinate dacitic and rhyolitic rocks. One notable feature is the appearance of æocoitasÆ from Ica (14oS) south to Santiago de Chile. These rocks have a calc-alkaline to alkaline affinity. From south to north, the continental crust gradually becomes thinner, allowing mantle material to rise towards the surface. Ophiolitic sequences of this type form a marginal basin in Colombia. Very low-grade regional metamorphism which affects the volcanic rocks also varies gradually from south to north. Between Santiago de Chile and Ica this takes the form of burial metamorphism, with moderate geothermal gradients (20o-30oC/km). Metamorphism in the Huarmey basin is transitional between burial and ocean-floor metamorphism, with very high geothermal gradients (>3000C/km). High geothermal gradients are also apparent in metamorphism of the Lancones basin, though less than the other basins. Ocean-floor metamorphism is present in the ophiolitic sequence in Colombia. Associated mineral deposits in the Huarmey and Lancones basins, and in the north, are of the volcanic massive sulphide-type (VMS). The principal deposits in Peru are Leonila Graciela (20 Mt Zn and Pb) and Tambogrande (40 Mt Cu and Zn). There are also smaller mines and prospects. To the south of Lima, manto-type Cu deposits (CuMT) are found with a mineralogy of chalcopyrites, pyrites, magnetite, actinolite and apatite. The main example is Raul Condestable (10 Mt Cu). Other prospects are present to the south and Chile has some very large mines of this type (El Soldado, Lo Aguirre). The notable differences between the CuMT and the VSM deposits are thought to be the result of the prevailing conditions in the earthÆs crust during the Hauterivian Albian. To the south, calc-alkaline and alkaline volcanic activity in aborted marginal basins, with thicker crust, was thick, produced moderate geothermal gradients associated with burial-type regional metamorphism and deposits of CuMT. In the north aborted marginal basins associated with calc-alkaline to tholeiitic volcanic activity and a gradually thinning crust, produced transitional regional metamorphism between burial-type and ocean-floor type, associated with high to very high geothermal gradients and VMS deposits. In Colombia these conditions led to ophiolite extrusive rocks, ocean-floor metamorphism and also VMS deposits.

Jan 1, 1999

The western Cordillera of North America, including more than 99% of Alaska, is made up of an agglomeration of litho-tectonic terranes, some of which have undergone large rotations and (or) translations. The larger terranes can be broadly grouped into a small number of composite terranes based on affinities in their lithology, structure, and tectonic evolution. The terranes reflect repeated episodes of marginal rifting as well as formation of marginal arcs, island arc chains, back-arc basins, and oceanic plateaus since late Proterozoic time. Accretion to the continental margin occurred mainly from Middle Triassic through Early Cretaceous time. Major northward dispersal of terranes was largely during the existence of the Kula plate from about 85-55 Ma. Major rotations are the mid-Cretaceous opening of the Arctic Ocean basin with counterclockwise rotation of Arctic Alaska and Laramide oroclinal bending of western Alaska. The present complex Cordilleran geology along the northeast Pacific rim is a sum of these earlier accretionary processes together with continued Cenozoic faulting and deformation that has been superimposed upon the agglomerated displaced terranes over a broad segment of the continental margin.

Jan 1, 1990

By P C. Hagan, J Chen, S Saydam

Fully grouted cable bolts have been used in underground mining industry for more than 40 years and are becoming more and more popular especially when severe geological conditions are encountered, such as high stresses and large cross-section excavations. The axial performance of cable bolts are mainly relied on the load transfer process between the cables themselves and surrounding rock masses via grout annulus. Therefore, the selected grouts play a significant role in determining the reinforcement quality for underground openings. In order to better understand the mechanical properties of Stratabinder HP grout, which is one type of cementitious grouts commonly used in Australian underground coalmines, plenty of unconfined compressive tests are conducted on it. Following diverse standards, two different kinds of samples are prepared and tested with the w/c ratio ranging from 0.35 to 0.45. During the test important mechanical properties including uniaxial compressive strength (UCS) values, Young’s modulus, Poisson’s ratios and so forth are recorded. Based on experimental results, the effect of w/c ratio on the mechanical properties of Stratabinder HP grout is studied. Beyond that, influences of sample size on the failure mode, peak strength as well as residual strength of this kind of grout are summarised and analysed.CITATION:Chen, J, Hagan, P C and Saydam, S, 2014. Mechanical properties of cementitious grout serving in fully grouted cable bolting systems, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 269–276 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

The treatment of mixed lead carbonate and lead sulphide concentrates at Mount Isa presents a problem which is unique ,in the lead smelting world; a problem whose solution is far from simple, and is not yet complete. Two years of study under plant conditions have definitely proved, however, that a most satisfactory sinter can be made in a single-pass roast.The object of this paper is to present a brief record of the development of the single-pass roast and a resume of current practice in the smelting plant. The sintering operation is discussed in greater detail, as it is upon this phase of the work that every item in the smelter operating programme depends.The smelter, to-day, presents a very much simplified layout, equipped for economical, straightforward operation, requiring, however, very careful and constant supervision, due to the extreme delicacy of the sintering operation and to the rapid and wide variati9n in the nature of the concentrates which are to be handled.

Jan 1, 1933

The theme of the conference this year is diversification. One way to diversify is through acquisition. The principle underlying the winner's curse is that in competitive bidding situations where the value of the asset bid for is uncertain the winning bid will overstate the true value of the asset. The successful bidder is blessed with the winner's curse. What this paper will explore is to what extent this is true; how acquirers can avoid being blessed with the winners curse; and show how joint venture deal structures are used within the mining industry to avoid the winners curse.

Jan 1, 1996

By D Wei

Large tonnages of low-grade haematite ores need to be treated every day in China. One of the mineralogical characteristics of these haematite ores is that the grain size of haematite is smaller than that of quartz and is not uniform in the ores. Therefore, a flow sheet consisting of gravity concentration, low-intensity magnetic separation, high-intensity magnetic separation and reverse flotation is mainly used to separate haematite ores in China, to obtain acceptable beneficiation performance and reduce the operating costs. Nowadays, whether based on mineral processing practice or theoretical analysis, the results show that the application of the above-mentioned flow sheet is able to take full advantage of these mineral processing methods and achieves satisfactory benefi ciation of haematite ores. For example, when the iron grade of the haematite ore is about 29 per cent Fe, a concentrate assaying 68 per cent Fe can be obtained and the recovery of iron is over 80 per cent. In the future, research work on the beneficiation of haematite ores should focus on investigating the most feasible particle size for gravity concentration circuit feed so that the operating costs can be reduced and ultimately the separation performance can be improved.

Jul 11, 2011

By A D. Pradana, D R. Pradana, Y H. Putra, Z Zulhan, T Hidayat

The high temperature processing of nickel laterite ore is currently dominated by the Rotary Kiln- Electric Furnace (RKEF) technology. The ratio of SiO2/MgO (S/M) in the ore is one of the critical parameters that determines the success of the RKEF process. Incompatible S/M ratios in the ore can cause aggressive chemical interaction between the slag and MgO refractory. The slag-refractory interaction at conditions relevant to nickel laterite ore smelting was investigated in the present study. Synthetic mixtures representing the slag compositions of nickel laterite ore smelting were prepared by mixing MgO, SiO2, Al2O3, CaO, Fe2O3, and Fe and heating the mixtures in steel containers at 1300°C under an argon atmosphere for 3 hrs. Pure MgO crucible were used as containment material in the melting process of the mixtures to represent the MgO refractory. The kinetics of the slagrefractory reaction were investigated using samples with selected initial S/M ratios of 2.0 and 3.0 (wt/wt) (with constant CaO = 3 wt per cent, Al2O3 = 5 wt per cent, FeO = 10 wt per cent) by performing melting at 1500°C in MgO crucibles for 5, 30, and 120 mins under an argon atmosphere. The effect of the S/M ratio in slag on the slag-refractory interaction was also investigated by performing melting of mixtures with different initial S/M ratios of 1.75, 2.0, 2.5, and 3.0 (wt/wt) in MgO crucibles at 1500°C for 120 mins under an argon atmosphere. After the melting process, each sample was quenched in water, mounted in resin, ground, polished, and coated. The interaction between the slags and MgO refractory was then evaluated by analysing the polished samples using a scanning electron microscope equipped with an energy dispersive spectroscopy (SEM-EDS). Thermodynamic simulations using FactSage™ 8.0 thermochemical software were performed based on the experimental slag compositions, refractory, and conditions to support the evaluation process. The results show that a higher S/M ratio in slag leads to a higher tendency for the refractory component to dissolve into the slag. A higher S/M ratio in slag also leads to an increasing extent of solid-state diffusion of iron oxide into the remaining refractory grains. The dissolution of MgO into the slag is rapid; the MgO concentration in the final slag increased by 2.4 wt per cent and 5.7 wt per cent at initial S/M ratios of 2.0 and 3.0 wt/wt, respectively, within 5 and 30 mins of the melting process.

Aug 21, 2024

By M Haest

This study demonstrates the application of HyLogging™ technologies for mineralogical characterisation of different iron ore types throughout the Hamersley Province (Western Australia), including a channel iron deposit (Murchison Metals Ltd) and bedded iron deposits in the Brockman and Marra Mamba Iron Formations (BHP Billiton Ltd).Drill core from these deposits was analysed using CSIRO’s hyperspectral drill core logging systems (HyLogging systems), which are commercially available at the AMDEL and AMMTEC laboratories in Perth (Western Australia), through a leasing agreement. These HyLogging systems provide high resolution photographs at 0.1 mm pixel resolution as well as visible and infrared spectroscopic refl ectance data at 1 cm spatial resolution. The minerals identified include haematite, goethite and its subtypes (ie vitreous and ochreous goethite), AlOH-clays (kaolinite, Al-smectite and white mica), carbonates, gibbsite, chlorite, amphibole and hydrated silica as well as water content. The abundance and composition of these minerals was established from the spectral data and was validated against XRF analyses.The full potential of HyLogging systems in the iron ore industry is only starting to be unveiled, but some major benefits have already been demonstrated:• HyLogging systems can delineate different ore zones by mapping the vitreous and ochreous goethites. This has a potentially large impact in mine planning and operations, as hard, vitreous goethite and soft, powdery, ochreous goethite have different processing characteristics that can affect plant throughput if not carefully managed.• HyLogging mineralogy can also be used to support stratigraphic interpretations of the host, for example in subdividing the Dales Gorge 1 - 4 submembers of the Brockman Iron Formation.• HyLogging can have a potentially signifi cant impact on waste rock characterisation, as many of the waste materials can be identifi ed and quantifi ed with hyperspectral data (eg clay-type,• hydration state).• HyLogging can provide accurate three-dimensional (3D) mineralogy to iron ore companies that will empower them to improve future exploration and resource planning.• Application of high resolution photography to further improve ore deposit domaining is also to be considered.

Jul 11, 2011

This paper considers three aspects of cemented fill practice and research in Mount Isa. Firstly, an account is given of the use of Portland cemented hydraulic fill, considering mainly the role and specifications of the fill used but including brief description of fill preparation and placement. Data resulting from a Portland cemented hydraulic fill sampling, curing and cesting campaign covering about 18 months of operating practice are presented, analysed and discussed. These yield information indicating the mode of operation of a fully-automated fill preparation station, as well as a means of comparing field and laboratory strength results. A technique with potential for use as a fill quality control without actual strength testing is also described. Results of a fill research programme conducted by the author in Mount Isa since early 1968 are presented, involving both Portland cemented hydraulic fill and altei._acive, cheaper, additives for cementing hydraulic Fill.

Jan 1, 1980