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Laboratory testwork was carried out on an overall orebody composite, of 2.9 per cent Cu and 4.2 per cent Zn, prepared from drill core taken from the Currawong fine-grained, copper-zinc massive sulphide deposit near Benambra in Victoria. While 90 per cent of the copper was readily recovered in a concentrate of 20 per cent Cu, after grinding to 95 per cent passing 38 microns, zinc responded poorly to conventional flowsheet/reagent regimes. Experience elsewhere with the use of reverse cleaning, to separate pyrite from sphalerite, led to a series of tests in which better (but still modest)metallurgical results were obtained. The best result was a zinc recovery of 55 per cent in a concentrate of 50.5 per cent Zn. The major loss of zinc occurred in the reverse cleaning stage where the unit recovery of zinc was similar to pilot plant results achieved at Mount Isa Mines on similar feedstock. Diagnostic mineralogy suggested that an overall zinc recovery of 70 per cent was probably the practical upper limit, at a 50 per cent Zn grade.

Jan 1, 1999

Evaluation of the Iron Blast Furnace Process using Heat and Material Balances of the Flame-Zone

Sep 13, 2010

By A Hughes, J Agius, T Ferguson, A Parbhakar-Fox, D Lester, L M. Jackson

Management of historic tailings is a major challenge facing the mining industry and its regulators. However, through improved mineralogical and chemical characterisation of such materials the opportunity to develop better rehabilitation strategies arises. Microanalytical techniques including microscopy, mineral liberation analysis and laser ablation inductively coupled plasma mass spectrometry (ICPMS) allow for improved tailings characterisation – but the challenge posed by these techniques is how to use them effectively. Additionally, data sets collected by such techniques must be properly integrated, only then can they assist in the identification of the most appropriate rehabilitation strategies. A study conducted at the Old Tailings Dam (OTD) located at the Savage River Mine, Tasmania allowed for the integrated use of several microanalytical techniques to help evaluate the benefits of a shallow water cover as a potential rehabilitation strategy. Samples (n = 144) from 14 trenches and 11 boring cores (2 m maximum depth) were collected across the OTD. These were subjected to routine acid-base accounting, with a subset subjected to detailed mineralogy using a modified sulfide alteration index (SAI), X-ray diffractometry and mineral liberation analysis (MLA). In addition, representative samples (n = 6) from across the OTD were subjected to laser-ablation ICPMS to characterise the pyrite chemistry. Our results showed that tailings in the northern area submerged under a natural water cover were relatively unoxidised from approximately 1 m depth, with SAI values of 1 to 2. Tailings from the subaerial southern portion were extensively oxidised to approximately 35 cm depth (SAI = maximum 5.8), with fresher materials observed underneath (SAI = 5 to 5.8). Pyrite from across the OTD is enriched in Co, Cu and Ni. Through the integrated application of microanalytical tools, we determined that establishing a water cover of at least 1.5 m depth across the OTD is a suitable rehabilitation option for this historic site. However, consideration for the reprocessing of these tailings to extract Co should be further investigated.CITATION:Jackson, L M, Parbhakar-Fox, A, Hughes, A, Agius, J, Ferguson, T and Lester, D, 2015. Microanalytical evaluations of the savage river old tailings dam, north-?west Tasmania, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 111–124 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

Strategic planning in mining is an important value accretive process. One of the most important aspects during the planning phase is determining the correct mine and plant design. The traditional mine site design (mine, plant, stockpiles, dumps) develops a fixed system for one set of conditions or expected values. A robust design is a fixed system that is designed to deal with a large range of conditions without changing the system design. A flexible design changes the system dynamically in response to changes in uncertainties. It is hypothesised that a robust design generates less value than a flexible design as it fails to realise the value of actively managing the operation. One of the most critical aspects in creating strategic value from a project is embedded in the design of the system. A flexible design has components that allow the design of the system to change over time. An operational plan is proposed as a hybrid of a robust and flexible design. This paper seeks to compare these different design methodologies. An analysis of the same case study is undertaken to compare these approaches, showing an a traditional net present value (NPV) of $1678 M, robust design NPV of $1787 M and an operational plan NPV of $1867 M - an increase of $170 M.

Dec 6, 2010

By N Hungerford, A Coote, S Doyle, D Henderson, F Della-Pasqua

A systematic, detailed airborne geophysical programme carried out in the Taupo Volcanic Region (TVR) in 2005 by Glass Earth NZ Ltd culminated in the identification of 21 epithermal gold targets. In this paper we present the follow up ground-truthing results from the first target drilled, Tahunaatara (TAH).   The Tahunaatara target was identified by means of a multi-disciplinary integrated approach (ôdata interventionö) that defined and ranked the target as being highly prospective for epithermal gold mineralisation. A follow-up ground resistivity survey over the target area revealed the presence of a ôresistorö buried beneath an extensive cover of recent volcaniclastic material. Geochemical soil sampling carried out in conjunction with the resistivity survey yielded anomalous gold values.   The host unit at TAH consists primarily of flow banded rhyolitic lavas, volcaniclastic deposits and tuffs of the Ohakuri Ignimbrite with small outcrops of silicified bedded breccias forming local topographic highs. Results from the first orientation drill hole show wide zones of intense silicification, clay alteration and mineralisation. Sulphide mineralisation is disseminated throughout the core in association with hydrothermal replacement and also occurs in association with quartz veins and infill in fractures (sulphide-only veinlets as opposed to quartz + sulphide veinlets). Textural evidence from drill core indicates that hydrothermal fluid flow was multi-staged with potential for multi-stage gold, and other elements. The presence of polymictic hydrothermal eruptive breccias indicates a hydrothermal vent system.   Alteration varies from argillic to silicic, with pervasive adularia and vuggy silicification also present. Chlorite is minor and associated with quartz, illitic clay and adularia. Assay results currently available confirm the presence of anomalous gold values in association with zones of vuggy silica deposition and intense silicification.

Jan 1, 2006

By V Novoselov, R Sabirov

Flotation processing technology of water-soluble minerals has made it possible to realise, since the 1960s, the wide scale industrial processing of potash and potassium-magnesium ores (about 200 million tonnes per year) as well as to create the multi-tonnage worldwide production of sylvite (KCl) for industrial and agricultural application. In this paper the particularities of the effect of reagents (blinders, collectors and frothers) during cation flotation in saturated saline solutions are outlined. New reagent modes for activating the effects of alkylamines during the flotation of KCl and the perfecting of technological flow sheets for processing potassium ore have been developed. The results of research on the reverse flotation of carnallite ore, with the help of alkylmorpholine û a new developing technology for benefication carnallite as raw material for the production of metal magnesium and fertilisers are listed. Examples are given of the industrial applications of processed reagent modes at potash flotation factories in Russia.

Jan 1, 2005

By C Bailey, T Kojovic, M M. Hilden, M S. Powell

The Julius Kruttschnitt semi-autogenous grinding (SAG) mill model was developed by Leung in the 1980s and extensively updated to the variable rates model by Morrell and Morrison in 1996. Since then only minor upgrades have been incorporated in the version distributed in the JKSimMet simulator. A number of improvements, developed over the course of the AMIRA P9 project and in recent independent work, have now been incorporated. These improvements are based on a power-based model that directly relates the degree of breakage with energy consumption. The new size-dependent breakage function has been incorporated. The upgrades include more accurate predictions for a wide range of mill fillings (ten - 40 per cent), slurry hold-up in the mill, pebble discharge rate and the influence of changes in feed size and ball load.The paper presents the status of progress in the model development. The upgraded model will greatly enhance its application to challenging design and optimisation studies required to optimise the performance of SAG milling circuits.CITATION:Kojovic, T, Hilden, M M, Powell, M S and Bailey, C, 2012. Updated Julius Kruttschnitt semi-autogenous grinding mill model, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 71-80 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

Newmont Waihi Operations is participating in the initiation of a community liaison forum in association with the local district council. The objective is to provide a forum for the free and regular exchange of ideas, concerns and information, and through improved communication seek to achieve a more comprehensive set of solutions to community, operating and closure issues associated with Martha Mine. A similar liaison forum has been operated on two previous occasions during earlier phases of the present mine's operation. This paper deals with the practical aspects of setting up a liaison forum to act as an effective conduit between regulators, mine operators, local businesses and the community. The mechanisms and procedures for identifying community issues and concerns are dealt with. The actions and structures required to ensure effective ongoing community 'buy in' at all levels are discussed. Corporate philosophies are addressed. Specific examples from Martha Mine, Waihi New Zealand will be used to illustrate the paper. This will include a brief explanation of previous and current community issues, Newmont Waihi's operations both at Martha Mine and the proposed Favona underground mine, and the practical issues involved in setting up a liaison forum.

Jan 1, 2003

By G Baird, M Seto

Reliable evaluation of in situ stress is an important phase in the analysis and design of underground excavations, particularly for evaluating the stability of underground structures to prevent failure or collapse. A technique for the estimation of the full stress tensor based on acoustic emission (the Kaiser effect) is being developed and trialed at the WA School of Mines. The result obtained compare well with the standard over-coring method. The advantages of the technique are that it is relatively cheap, non-time consuming and is applicable to in situ stress measurements at depth in remote regions.

Jan 1, 2002

By L Lorenzen

In this paper, we developed and implemented a fuzzy logic expert system capable of evaluating the degree of sustainability within the context of gold mining operations. The newly introduced approach of evaluating sustainability in the gold mining industry has the merit of sufficiently handling diverse, sustainable, development-related qualitative and quantitative data owing to fuzzy logic technology capabilities in dealing with linguistic syntax. The economic, environmental and social indicator inputs were independently evaluated and then combined with the aid of fuzzy logic to provide an overall sustainability index on a scale of zero to one. A total of 66 independent indicators were identified and applied in our model. The novelty of this work lies in providing a coherent numerical and automated approach in evaluating sustainability in the context of gold mining operations. In addition, the model can aid policy- and decision-makers in arriving at consistent decisions regarding the degree of sustainability on various aspects of gold mining operations. The functionality of this model will be illustrated through several examples.

Jan 1, 2007

Iron Concentrate Synthesised from Waste Ferrous Sulfate Produced in Titanium White Preparation

Sep 13, 2010

Geotechnical conditions in the Lochiel Deposit are somewhat unusual, and thus geotechnical and hydrological investigations have assumed a high priority. The cost of mining the deposit has been shown to be very sensitive to geotechnical design parameters, and it is now seen to be of paramount importance to establish a high level of confidence in the design parameters used for mining cost estimation. Geotechnical investigations in the Lochiel Deposit reached a crossroads in 1985, when there appeared to be several quite different and equally attractive routes to follow to establish a satisfactory level of confidence in geotechnical mine design parameters. Three main options were identified, referred to as the No Further Work Route, the Drill and Trench Route, and the Trial Pit Route. The No Further Work Route was ruled out as being technically unsound and as satisfying none of the Electricity Trust of South Australia's (ETSA's) or the State Government's requirements. The planning process for further geotechnical investigation involved: clearly identifying the current status of work and significant geotechnical and geological factors planning and costing the alternative schemes for improving knowledge assessing the increase in knowledge to be gained from the alternative schemes . choosing the preferred scheme This process resulted in ETSA's

Jan 1, 1986

By P Wigley

New methods of analysing and modelling flotation circuits have been developed as part of the AMIRA P9 mineral processing research project. A study using these techniques was conducted on the Olympic Dam copper flotation circuit to provide the following outcomes: an estimate of the flotation cell hydrodynamic properties and froth performance characteristics, and identification of potential areas for improvement; an estimate of the feed floatability parameters for basic model development; and identification of potential flotation circuit improvement opportunities. A flotation circuit model of the Olympic Dam copper concentrator was developed using the data collected from mass balanced site surveys, along with hydrodynamic data, froth performance data and numerous laboratory batch flotation tests. The simulator that has been developed from the model has the ability to estimate the influence of selected changes (such as circuit changes) on flotation circuit performance. Several stream destination simulations were conducted to provide guidance for further testwork and possible circuit improvements. The results from these simulations are presented.

Jan 1, 2003

Cretaceous to Cenozoic sedimentary basins in Western Southland include a wide range of non-marine and marine sediments, in a structurally complex setting dominated by major fault systems. A reassessment of their mineral potential confirms large quantities of nonmetallic minerals (limestone, aggregate, marl), and smaller reserves of bituminous coal, lignite, clays, and oil shale. Hydrocarbon potential is largely untested. Metallic minerals are present in trace amounts, apart from platinum group minerals and some detrital gold. In the offshore area, seismic data suggest the hydrocarbon potential is significant. The Orepuki area has the most interest onshore.

Jan 1, 1992

By A F. Cooper

Otago Schist in the Mount Patriarch, High Burn and Cameron Creek areas of northwest Otago grades from textural grade IIA in the east to textural grade III in the west. The entire region is of the actinolite-pumpellyite metamorphic facies. Lithologies in the area are interbedded turbidite sequences comprising pelite and psammite together with pebble conglomerate, greenschist and metachert horizons. The mineral assemblage of the schist is typically quartz-albite-epidote-actinolite-pumpellyite-chlorite-stilpnomelane-calcite. A good foliation is well defined in the area and is predominantly parallel to bedding, except in hinges of mesoscopic isoclinal folds. The structure of the area appears to be defined by a large southwest plunging isoclinal fold defined by bedding with a steeply dipping axial planar foliation. Kink folding and dextral strike-slip faulting in the area postdates the ductile phase of deformation. Pods of rhodonite, rhodochrosite, spessartine garnet, coombsite, caryopilite, Mnstilpnomelane and Ni-Cu-Zn sulphides were found in concordant metachert layers in the Mount Patriarch area. Metachert was also found in float in the Cameron Creek area. Malachite occurrences relating to copper mineralisation were also noted in a green metachert horizon on the eastern flank of Mount Patriarch. The coombsite, in only the third observation worldwide, is the most Fe-rich variety reported.

Jan 1, 2003

By G B. Ebsworth, J Krokowski de Vickerod

Several drilling programs at Maldon have produced 7790 core samples, which were assayed for gold, with 2825 of the samples assayed for nine other metallic elements. There is a lack of correlation between gold and all other elements. The situation, however, changes dramatically when sorted according to the abundance of arsenic. In the populations where As >200 ppm, there are strong, positive correlations between gold and several elements. There is also a strong positive correlation of Au with the weighted sums and products of all elements with the elemental averages as a weighting factor, and Bi*Sb and Bi*As elemental products. In these populations, there is also a strong positive correlation between the logarithms of Au and logarithms of each element, as well as the elemental sums and products described above. The correlation coefficients increase with higher As cut-off values.All elemental distributions but especially gold show a high-nugget effect and display high skewness and dispersion, low kurtosis, and common outliers. The distributions of their logarithms are several magnitudes less scattered and without outliers. Thus, the logarithmical distribution correlations are best for practical use.Correlation coefficients were T-tested and are statistically significant. The elemental correlations, particularly those of logarithmic values of weighted sums and Bi, could be used as a gold path finding tool at Maldon. After a preliminary assay for gold and arsenic, only samples with As > 200 ppm should be assayed for other elements. Higher values of gold-correlated elements or elemental ratios, in samples with low gold grades, may increase confidence that gold is under reporting due to its highly nuggetty nature.CITATION:Krokowski de Vickerod, J and Ebsworth, G B, 2012. Correlation as a gold path finding tool at Maldon, Victoria, in Proceedings Narrow Vein Mining 2012 , pp 131-144 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

Determination of Porosity and its Influence on Specific Surface

Sep 13, 2010

By R Miller, D Hawcroft

The business environment is never still and there has been enormous change in demand, technology and opportunity during the last decade. In order to succeed it is necessary for organisations to change the way work is planned, scheduled and carried out. This is necessary just to survive over time. The success or failure of the business is strongly influenced by people; the way they work, the way they are guided and their feelings about being part of both a team, as well as an organisation. Our Sustainable Integrated Management System (SIMS) philosophy is built on the belief that people want to be constructive and creative and it is their environment and working relationships that influence how their energies are directed.

Jan 1, 2000

I have spent most of the past 35 years working as an economic geologist in the area of exploration and development of base and precious metals. Most of this period has been as an employee of Trans-National-Corporations (TNC's). I presently act as a consulting geologist to a joint venture company, bringing together two such TNC's: Anglo American Corporation and affiliated companies De Beers (Diamonds) and Minorco (Metals mining outside of Southern Africa), and Normandy Mining Limited ofAustralia. Normandy is presently through its gold arm PosGold, Australia's largest gold miner and Anglo American can claim to be the world's largest gold company producing over 280 tonnes of gold a year, more than twice its nearest rival Gold Fields of South Africa. In addressing this topic, the role that Government can, and should play in mineral development, I will be drawing heavily on some examples from these and other TNC's experience in recent offshore mining investment.

Jan 1, 1995

New ZealandÆs share of global greenhouse gas emissions, at about one fifth of one per cent, is very small. But the profile of those emissions is unique among OECD countries; more than half come from methane and nitrous oxide associated with livestock agriculture. Consequently, fulfilling its obligations under the Kyoto Protocol is potentially quite onerous for New Zealand.In this paper we use a single region, static general equilibrium model to assess the implications for New Zealand of various climate change policy options. The energy and agriculture sectors are modeled in a detailed manner to enable realistic simulations to be carried out.Choosing an optimal set of policies is made more difficult by the fact that New Zealand relies heavily on emission intensive sectors for much of its export earnings. For example, one emission intensive sector alone, dairy, accounts for over 20 per cent of all merchandise exports. Avoiding carbon leakage is therefore an important consideration in selecting appropriate greenhouse policies.Our analysis shows the degree of sectoral adjustment required is substantial. In addition, the total costs depend on the uncertain level of variables such as the global carbon price and the level of afforestation activities in New Zealand, ie the rate of new forest planting.

Jan 1, 2002