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It is a great privilege to be invited to give this address at this centenary conference. A centenary is a time for recollection, for celebration and for looking ahead. The AusIMM has much to celebrate and many things to recall. I hope in this address to make some useful comments about Australia's future (and mindful of but not forgetting New Zealand), looking ahead for 25 years or so, and the mining industry's role in that future.

Jan 1, 1993

By N J. Potter, N W. Brand, J M. F Clout

The increasing demand for iron ore with low concentrations of trace elements, puts increasing pressure on iron ore producers for high-quality material. Understanding the mineralogy, petrography, chemistry, and mineral association of iron ore deposits is becoming increasingly important to provide iron ore products that meet the ever-increasing standards of steel mills. Limited attention has been paid to documenting new orebodies beyond bulk RC drill chip assays and product specification data. Therefore, limited information is known about the spatial distribution of minor and trace elements at the hand specimen scale, and elemental deportment within different ore and gangue minerals. In this study, samples from high-grade microplaty hematite, supergene-enriched martite-goethite and hematite iron ores are examined for their elemental and mineral associations. These samples contain distinctive minor and trace element distributions, with the mapping of deleterious elements (eg Zn, As, Cu) enabling the deportment and abundance within the ore and gangue minerals to be assessed. Results from this study show a diverse range of minor and trace mineralogy that are present in typical iron ore samples, in abundances below the detection limit of routine XRD scans, that host the deleterious elements, including but not limited to, sphalerite (Zn and S), chalcopyrite (Cu and S), xenotime (P and Y), apatite (P and Ca), cryptomelane (K and Mn), barite (Ba and S), alkaline feldspar (K, Al and Si) zircon (Zr and Si) and chromite (Cr and Al). The presence of these minerals and associated deleterious elements, even at low concentrations, has implications for producers, with the ongoing restrictions and tightening of environmental constraints in shipped iron ore products. By understanding the distribution and location of these elements within the iron ore, steps can be considered to maintain increasingly higher quality iron ore supply around the world.

Nov 8, 2021

By G Nicholas, S Coward, J Vann, R Wolff, S Jackson, S Moayer, A Bye

"A new approach to mineral project evaluation is described called Scenario-Based Project Evaluation (SBPE). SBPE incorporates well established æscenario planningÆ and æscenario thinkingÆ approaches, which are used extensively in other industries,?most notably the?petroleum industry. While most scenario planning is qualitative and non-probabilistic, the approach described here includes both quantitative and qualitative aspects. SBPE is complementary to optimisation approaches and allows mining firms to build and operate projects that are more robust in the face of adverse changes as well as proactively respond and exploit the upside offered by a realistic assessment of variability. The approach has potential to improve project performance and decrease operational risk. It also has important applications for currently operating mines.Conventional evaluation of metalliferous mineral deposits uses estimates of metal grades and deleterious attributes in singular æorebody modelsÆ, usually 3D block models, which fail to capture two critical aspects that underpin the realised value of mining projects: the inherent uncertainty of the estimated attributes the spatial variability of attributes, at the scale of mining selection, which impact on downstream processing steps and fundamentally drive realised value. While singular models are appropriate for estimating block averages, conditional simulation (CS) models of the relevant attributes are needed to represent uncertainty and capture spatial variability. Any attributes that can be either built into CS models and/or modelled in the envisaged mining/processing steps, can be evaluated fully through to highly ægranularÆ (ie detailed and un-smoothed) cash flows. A complete view of SBPE relies on selected strategies being tested against plausible æscenariosÆ of factors external to the project and thus outside management control. æExternalitiesÆ captured in such scenarios include market prices, costs and taxes. Via SBPE, project managers may demonstrate that there is material value in preserving or purchasing options that provide future flexibility to respond to the changing externalities or changes in orebody performance. Such flexibility generally comes at a cost but is very difficult to value. It is argued that full value chain evaluation using SBPE can help to value these options for a mining company. A case study for a gold mine is presented.CITATION:Vann, J, Jackson, S, Bye, A, Coward, S, Moayer, S, Nicholas, G and Wolff, R, 2012. Scenario thinking - A powerful tool for strategic planning and evaluation of mining projects and operations, in Proceedings Project Evaluation 2012, pp 5-14 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

May 24, 2012

By Rolley P

In the course of reviewing grade control practices at the Marvel Loch gold mine in Western Australia in 1992, FSSI Consultants developed and implemented a novel approach to ore selection using a method to maximise financial return (the MP method*). The approach was based on improved grade control sampling and an ore selection method which directly incorporates both a measure of the uncertainty in knowing the true grade of selection units in the definition of ore, as well as the operating cost and revenue parameters of the mining operation. During the past four years, FSSI Consultants have evaluated and refined the use of this approach and have implemented customised variations of the MP method at seven gold mines and a gold-copper mine in Australia. The previous methods of ore selection at most of these operations were based mainly on polygonal - sectional methods of grade estimation. At all of the sites where grade control optimisation has been given a fair trial over several months of production, the use of the MP method has been consistently rewarding to the mining operations. The benefits include increased run of mine ore stockpiles and low-grade stockpiles and decreased fluctuation in the production grade. Most operations have also benefited from a consistent ability to improve production grade through high-grading of the increased ore production. The increase in ore production has the logical benefit of reducing stripping ratios, increasing mine profitability and mine life.

Jan 1, 1997

By W J. Botha

The Palaeoproterozoic Transvaal Supergroup in the northern Cape Province of South Africa hosts high grade (>60 per cent Fe) hematitic and specularitic iron and manganese mineralisation. The mineralisation is primarily exposed along the western margin or in the central part of a major interference fold structure known as the Maremane dome. The bulk of South AfricaÆs iron ore production is currently provided by two active mines, Kumba Resources megaton Sishen iron ore mine on the northern end of the dome, and the smaller Assmang Beeshoek mine on the southern closure. The undeveloped Sishen South deposit, which contains ~400 Mt of high-grade hematite ore, is located approximately 9 km towards the southwest of Postmasburg. It forms a linear extension of the Beeshoek mine and as such contains comparable laminated, breccia and conglomeratic iron mineralisation. The Transvaal Supergroup sediments were deposited in two distinct fault-controlled basins on the Archean Kaapvaal craton. Basement rocks in the western Griqualand West basin are formed by a carbonate platform sequence (Campbellrand Subgroup), which is overlain by a thick sequence of banded iron formation of the Asbesheuwels Subgroup. A major unconformity separates these rocks from the red-bed Gamagara Formation, which is correlated with the base of the Olifantshoek Supergroup. Diamictites and lavas of the Postmasburg Group have been thrust over these units from the west. The mineralisation process is related to regional scale supergene iron enrichment of Kuruman banded iron formations along the unconformity. During regional tectonism associated with the Kheis orogeny (2400 - 1700 Ma) the Maremane dome was uplifted, and the basal dolomite units thus exposed to erosion and karstification. The overlying banded iron formations collapsed into karst sinkhole structures where leaching of silica and enrichment of hematite occurred. Although the exact mechanism of the mineralising process remains unclear, karstification preserved components of the original concordant laminated and massive ores. These ores were subsequently eroded and deposited as conglomeratic and gritty ores down-dip of the Maremane dome in alluvial fan systems. A thin veneer of recent calcrete or Tertiary Kalahari clay beds masks the subsurface geology and most of the orebodies, thus ground geophysical gravity surveys proved excellent exploration tools to penetrate the surficial cover. These surveys were used extensively for delineation drilling and to deduce the subsurface geology and structural development of the area. Finally Sishen South orebodies were modelled with ModelVision software in an attempt to obtain an exploration template for the surrounding area.

Jan 1, 2005

The late Carboniferous to early Permian Featherbed Volcanics cover an area of about 3000km near the western margin of the Hodgkinson Basin, in northeastern Queensland. The dominantly ignimbritic volcanic rocks are mostly confined to a single, composite, volcano-tectonic depression, but, along with the associated intrusive rocks, may be divided into two main groups: late Carboniferous I- type rocks and early Permian A-type rocks. Late Carboniferous I-type andesitic to rhyolitic ignimbrites and minor andesite lava crop out in the southeastern, southern, and southwestern parts of the complex, mostly confined to a basin-like depression, or "sag" structure, and are associated with coeval dioritic (and rare gabbroic) to granitic intrusive rocks. Extensive Sn, W and base- metal, and some Au, mineralisation are associated with these rocks, particularly in the southeast. The main part of the complex is of early Permian age, and consists almost entirely of A-type rhyolitic ignimbrite and relatively minor volumes of lava intruded by a peripheral ring dyke of porphyritic microgranite and by resurgent-type plutons of porphyritic microgranite and microgranodiorite. These rocks are associated with sparse base-metal, Au, U, W, and Sn mineralisation.

Jan 1, 1987

In the last several years we have seen the demise of the Department of Mining and Metallurgy at the University of Melbourne, the removal of extraction metallurgy from the Department of Metallurgy and incorporation of it within a School of Mines at the University of New South Wales, and the joining of a small Department of Metallurgy with a Department of Chemical Engineering to form a Department of Chemical and Materials Engineering at the University of Newcastle. Most of these changes have been forced by the logical application of the principles of accounting, the currency for such accounting being the Whole Student Unit (WSU). It is not my intent to address the problem of attracting young people into courses in metallurgy (including extraction metallurgy) which, at present, is the only way to introduce black ink into the WSU accounting ledger. Rather, I wish to express my disquiet over the trends, illustrated by some of the above occurrences, of separating out extractive metallurgy from METALLURGY by suggesting in broad terms how a course in metallurgy should be structured. I firmly believe that the mechanical metallurgist and materials engineer need an exposure to chemical and extractive metallurgy; similarly, the extractive and process metallurgist should, in my view, have a good grounding in the interrelationships between composition, structure, and properties, this topic being the core of the basic subject physical metallurgy.

Jan 1, 1987

By Ritchie AS

The principles of chromatographic and electrophoretic separations are described in simple non-mathematical language. Brief details of the analytical procedures and of equipment are given. Partial analyses of rare earth elements in monazites from four localit- ies in New South Wales are compared with analyses from other localities. The presence of uranium in two of the monazites is recorded. The occurrence of rare earths in nature is outlined and its geological significance is indicated, A low capital cost method of analysis of rare earths in monazites is Introduced.

Jan 1, 1972

By D Clarke, I Minniakhmetov

This paper describes the application of the SBRE framework to model the Olympic Dam deposit, one of the largest copper and uranium deposits in the world. Geostatistical simulations are the best practice for quantifying uncertainty in the mineral value chain and estimating resources. However, these simulations are currently undertaken on an ad hoc basis in the mining industry due to the high requirements in computing resources and capabilities in advanced geostatistics. The SBRE project provides a standard framework to test, build, and run conditional simulation workflows, which has been applied to the Olympic Dam deposit. Conventional geostatistical methods face challenges when modelling the Olympic Dam deposit, such as non-stationarity, non-linear correlations, and a large number of grid blocks to simulate. To address these challenges, a combination of methods was used, including projection pursuit multivariate transform, trend-residual decorrelation, pluri-Gaussian simulations, and turning-bands simulations. Various tools and applications were used to build the model, including in-house developed applications, Autovariogram software (Varify), and the RMSP python library. All computations were accomplished on the AWS cloud using the EC2-Batch service. The final set of simulations was validated using various methods, such as grade-tonnage curves, histograms, swath plots, and variogram reproductions, as well as validation using historical samples back-testing. The study highlights the importance of an automated, modular, and scalable framework in the development of conditional simulation workflows and describes the learning gained from trials of different combinations of methods and software

May 24, 2023

The valuation of resources companies is open to a huge amount of subjectivity. Not only are valuations subject to fast changing assumptions, such as commodity prices, exchange rates, ore grades, etc., but there is also no common agreement on the methodology to be used. To borrow from Malcolm Fraser, life wasn't meant to be easy for the resource company valuer. I will demonstrate three recent examples of valuations carried out but where the market or actual transactions done show very different results.

Jan 1, 1989

By Champigny N, Grimley P. H

To a bank that granted his request for a loan, the late American humorist Robert Benchley responded, `I don't trust a bank that would lend money to such a poor risk'. This quotation is unlikely to be the norm among mining companies that secure project financing. However, a poor appreciation of one of the key risks of a mining project, the reserves, often results in disastrous financial consequences. This conclusion is the subject of the discussion and analyses presented in this paper.

Jan 1, 1994

By G Zhang, I Glacken

Multiple indicator kriging (MIK) has been used in the minerals industry for some decades. As one of the non-linear estimation methodologies, MIK has advantages related to resolving multiple or mixed populations, high variability data and strongly skewed distributions. Applying the MIK methodology requires a lot more effort when compared to other non-linear methodologies, for example localised uniform conditioning. This is due not only to the variogram modelling for multiple indicators, but the validation is also very important because the panel model is fundamental for follow-up work, including the generation of recoverable resources at the local or SMU scale. Apart from this, only a few reported case studies of MIK have documented post-processing of the estimated modelled distribution, representing the probability distribution at point scale at un-sampled locations. The MIK post processing should include the change of support from the point scale to the panel scale, and then the extraction of quantile values from the panel conditional cumulative distribution function (CCDF) for localisation of grades into the SMUs within each panel, based on a ranking estimate marking the SMUs from high to low. In this paper, we present a case study on a gold deposit with the MIK method with full-post processing implemented for recoverable resources. The MIK point estimate was carried out with an indirect lognormal change of support from point to panel scale, and localisation was done with a custom script. The localised uniform conditioning (LUC) method was also applied for comparison purposes. The comparison shows that MIK has advantages compared to LUC when comes to capturing the high-grades, especially when mixed or varying anisotropy is present within the mineralisation.

May 24, 2023

By J H. Zietsman

The transition to more sustainable metal production is receiving much attention at present, and the iron and steel industry is at the centre of the conversation. New, more environmentally friendly production technologies, such as direct reduced iron (DRI) smelting furnaces, need to be developed in a short period of time. This necessitates increased use of computational modelling that incorporates more accurate material descriptions. The combination of large-scale multiphysics models of high-temperature processes with CALPHAD material descriptions leads to infeasible computation times. This can be resolved with the previously reported RapidThermo framework, which has been demonstrated to make equilibrium calculations orders of magnitude faster, within controllable limits of accuracy. In this paper, we explain how further material properties, which are important to modelling hightemperature reactors, can be added to the RapidThermo framework. This can improve the accuracy and usefulness of process and multiphysics models in the development of new technologies, which can significantly accelerate development cycles.

Aug 21, 2024

The object of this paper is to give an insight into various metallurgical operations involved in the making and shaping of steel for shipbuilding at the Newcastle plants of the Broken Hill Proprietary Co. Ltd., Commonwealth Steel Co. Ltd. and the Port Kembla plant of Australian Iron and Steel Ltd. Whilst not steelmakers, inasmuch as their processes start with semi-finished. steel supplied by the Steelmaker, the plants of Stewarts and Lloyds (Aust.) Pty. Ltd. and their associate company, British Tube Mills, Rylands Bros. (Aust.) Pty. Ltd. and the Newcastle and Kembla plants of John Lysaghts (Aust.) Pty. Ltd. make substantial contributions to the Australian shipbuilding industry, principally by way of boiler tubing and wires for welding rods and sheet steel, including special silicon lamination sheet for electrical motors.THE MAKING OF STEELThe making of iron and steel began as an accident, slowly developed as an art and has not yet become an exact science. The iron age dawned on the day when, by chance, man's primitive ancestor built up the wall of his fire with ironstone. In the ashes of the fire he found pieces of sponge iron from which he hammered out the first sample' of wrought iron. For many centuries iron ·was manufactured in bloomeries and occasionally, when the temperature was excessive, the iron combined with some carbon and steel was produced. But it was not till '1740 that steel was manufactured under controlled conditions. In that year Huntsman invented the crucible process which held undisputed sway for over a 100 years until in 1856 the invention of the Bessemer process revolutionised the whole industry.From then on, rapid progress was made. The Siemens...

Jan 1, 1951

By J McCluskey, N Barros

"Long-term strategic planning at BHP Billiton’s Western Australia Iron Ore business aims for sustainable value maximisation of its large, long-life, low-cost, expandable mineral inventory and supply chain infrastructure. While mine plans are key components of this value equation, this objective requires a whole-of-business approach through comprehensive consideration and optimisation of the full value chain. Only through a system view do we believe that the value proposition of a set of plans is truly optimised.The fundamental considerations include: mineral inventory information, given its intrinsic uncertainty and risk/knowledge horizon a marketing view of future quality premium/discount based on overall market quality load whole of supply chain optimisation on a throughput accounting basis alternative sequences of capital decisions closure costs with significant magnitude of total movement requiring optimisation as part of the plan. In addition, the plan provides a view of acceptable uncertainty levels at different times in the future.BHP Billiton Iron Ore uses a structured Life of Asset planning process that supports the business with the optimisation of its maximum value proposition through a non-deterministic scenario-based optimisation approach on an annual basis. This is a key input to each year’s medium-term plans and budgets, including activities identified through a value of information approach that resolve the key uncertainties and steadily improve confidence in the plan.CITATION:McCluskey, J and Barros, N, 2014. Life of asset planning, uncertainty and value optimisation of the iron ore business – from exploration, to market, to closure, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 33–40 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 24, 2014

Obtaining correct assays for gold determinations relies on the correct methods being chosen and the assayer being made aware of the mineralogy of the sample and its general origin. Usually when a geologist or metallurgist obtains "incorrect" gold assays the problem can be traced to poor communication between the geologist or metallurgist and the assayer.

Jan 1, 1986

IN the present paper it is the writer's intention to largely confine the subject-matter to details relating to the metallurgical practice in connection W,ith the blast roasting of lead ores at the Port PiJ;ie works of the Broken Hill Associated Smelters Pty. Ltd. rather than to elaborate on mechanical plant details which are more or less standard equipment of the average Dwight and Lloyd or Huntington-Heberlein blast roasting installations (hereinafter referred to in the text as D. & L. and I.I. & H. respectively). The present blast roasting plant is a combination ot D. & L. straight line machines and IQ-ton H. & H. pots. The latter installation was an operating unit prior to the introduction of the D. & L. machines, the pre-roasting then being accomplished in Ropp roasting furnaces.On the introduction of the D. & L. machines the use of the Ropp roasting furnaces as a pre-roasting unit was discontinued, and this step of the process was then carried out on one section of the D. & L. installation.Consequently, then, the present plant consists of (1) A section of D. & L. machines, which operate solely as a pre-roastiIig unit. (2) A section of D. & L. machines which operate to their full capacity as 3, final roasting unit and treat the main portion of the pre-roasted material.

Jan 1, 1922

There has been much debate in the past as to whether the Australasian Institute of Mining and Meteorology ("AusIMM") should issue valuation guidelines in addition to the ASX and NCSC requirements. My experience in preparing independent expert reports has been that "best practice" sets higher standards than any laws or requirements set out by the ASX and NCSC. This is where I see the AusIMM coming in.

Jan 1, 1989

The success of any industry depends on the planned integration of the policies and resources of the key components of the Australian economic and political structure - government, industry management, education, research, and the human resources of the industry. The Australian Mineral Industry, like Australia itself, has grown and developed at a rate not foreseen by many of our founding fathers and early industry leaders. Hence, now, as we approach the 21st Century, we need to re-think our approach to the significant new problems that are beginning to face both government and the Mineral Industry. Government initiatives, government information and support services, industry re-structuring, and research and development support, need to be carefully re-evaluated, re-diredted,. and strengthened, so that government, the community, and the Mineral Industry produce and receive the optimum education and research strategies and services. The support of academics and researchers, the development of facilities, and the design of new Courses for the future successful and beneficial exploitation of minerals need particular consideration.

Jan 1, 1986

By O Ishiyama, L Lu

Sintering is the most economic and widely used agglomeration process to prepare iron ore fines for blast furnace use. Due to the depleting reserves of traditional high-grade iron ore, there have been considerable changes in iron ore resources available throughout the world, especially in steel mills in East Asia. Corresponding to the changes in the availability of iron ore resources, the amount of impurities in iron ore has been slowly increasing. Some of these impurities have been found to have deleterious impacts on sinter quality and sintering performance. In the meantime, an increasing number of large blast furnaces with inner volumes of more than 5000 m3 have been built that require more sinter and are often more demanding in terms of the quality requirements of the ferrous materials. Finally, sinter plants are facing increasing pressure due to more stringent regulations regarding their environmental impact. This paper gives an overall review of a variety of technologies developed worldwide to tackle the changing raw material characteristics and mitigate emissions from sintering operations.CITATION:Lu, L and Ishiyama, O, 2015. Recent advances in iron ore sintering, in Proceedings Iron Ore 2015, pp 61–68 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015