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By Hutton W

The Argyle Diamond Mine is the first significant diamond producer in Australia. The project has been developed with new concepts in circuit design, process control technology, organisational development and training. After its first year of operation, the Argyle Heavy Medium Separation Plant has proven extremely efficient in recovering diamonds. Apart from cyclone wear, no major problems have been encountered. Ferrosilicon consumption is well below the design level which is a reflection of the sound design of the medium circuit. An Audit Plant continuously monitors the Heavy Medium Separation Plant tailings for diamond loss.

Jan 1, 1987

By D Craw, C E. Martin, C Smith, C Rufaut

Wangaloa Coal Mine opened in 1945, and by the time of its closure in 1989, had produced 750 000 tonnes of coal and disturbed an area of 75 ha. The original mining licence required land rehabilitation to exotic forestry, however the current owner, Solid Energy, has worked with Crown Minerals and local councils to write a new rehabilitation objective. The site is now being stabilised and replanted with native species, and may be available for public use before the coal mining licence expires in 2007. Site discharge permits expire in 2017, and by that time, it is anticipated that discharge water chemistry will be similar to background levels. MWH are currently contracted for management of the mine rehabilitation project. The Kaitangata coal unit mined at Wangaloa is sulfurous lignite with associated pyrite. Kaitangata coal contains 3.2 wt per cent sulfur, which is higher than most New Zealand coals. Initial analyses at Wangaloa indicate low pH (2.56.2) values in soil, groundwater and surface waters as a result of acid rock drainage (ARD) processes, leading to increased metal mobility and challenging conditions for vegetation. Pilot studies indicate pinus radiata needles contain up to 67 mg/kg boron, and elevated As, Cu and Zn concentrations in surface waters. The main lake at the site has a pH of approximately 4.9, despite lime dosage in 2002. There is a real need for a complete geochemical model of the Wangaloa coal mine. Such a model could be applied to similar restoration projects, and would assist by pinpointing geochemical processes and toxic metal relationships most harmful to the receiving environments. Using this model, rehabilitation in the future will be targeted and more efficient. This project is part of a larger scheme to characterise and model the Wangaloa mine site restoration, including waters, soil, vegetation, geology and invertebrates.

Jan 1, 2003

The economics of gold differs from that for base metals mainly because a large component of gold demand is investment or stock demand whereby the metal is purchased and stored for monetary or anxiety motives rather than fabricated into industrial products.The second major component of gold demand is fabrication, principally into jewellery but also, to some extent, into industrial products.Supply to the Western private- gold market comprises non-Communist mine production, Communist sales (chiefly from the USSR), and, finally, net sales by the Western Central Banks, which have total stocks of about 35,000 tonnes and which are sometimes net buyers as well as sellers.The different components of demand and supply fluctuate from year to year.

Jan 1, 1984

By J Player, G Sweby

The material properties and hence performance of saturated alluvial sediments slope can be incorrectly forecast if the water content is not preserved, and materials properties not correctly determined. The occurrence of saturated sediments in the Western Australia (WA) Goldfields, while not common, should be a significant investigation focus. Geotechnical engineers new to the area may be unaware of this and hence the importance of correct testing and determination of the material strength. Application of appropriate analysis to determine stable pit slopes to an acceptable level of risk, is not possible unless the appropriate strength and hydrogeological parameters have been established at the outset. A back analysis is presented of a pit that had extensive slope failures in alluvial clay-rich sediments with discussion on the approach adopted by the original design engineers to assess pit wall stability and consequent poor slope performance. Learnings from a full pit 3D back analysis are presented, with an approach to geotechnical and hydrogeological investigations and analysis for slopes in similar materials.

Jun 22, 2022

Following extensive trials on a 100 000 tpa Research and Development facility at Kwinana, Western Australia, Hismelt Corporation (wholly owned by Rio Tinto) are confident of the future commercial success of this technology. The Hlsmelt process uses iron ore fines and non-coking coals to produce molten pig iron suitable for feeding to BOF and EAF steelmaking vessels. The unique process configuration combines direct injection of raw materials into the molten iron bath, high rates of metal and slag mixing, and effective post-combustion of the bath gases to achieve efficient coal utilisation. This is the key to the strong economic performance of the process.

Jan 1, 1999

By Corbett GJ

Epithermal gold-silver deposits occur in young volcanic terrains where post-mineral cover commonly impedes the search for mineralisation. At the Togi Project in Honshu, Japan, a complex mineralised system is largely covered by post mineral volcaniclastics. A combination of high resolution electrical resistivity surveying and detailed airphoto interpretation has, with close geological control, enabled synthesis of structural and alteration characteristics of the Togi geothermal system, in turn permitting ranking of the prospects for drill testing.

Jan 1, 1990

Both safety and productivity in underground gassy coal mines can be improved substantially if an appropriate gas management system is introduced. A strong direct relationship exists between the gas emission rate, roof and floor strata relaxation zones characteristic, mining activities and gas drainage practices. Detailed knowledge of geological factors, gas and coal-rock properties, as well as mining systems are necessary for the methodology used in predicting overall underground gassiness, and planning gas capture and ventilation systems. Early gas emission calculations for various mining activities, particularly for the longwall mining system are essential. A reasonably accurate prediction of gas make as well as the design of ventilation, gas recovery (drainage holes) techniques can be made using 'Floorgas' and 'Roofgas' computer simulations, provided sufficient geological, mining, and gas data are made available.

Jan 1, 1998

By Piotto P

Pit optimisation algorithms are designed to produce a pit with maximum value, but for certain minerals like iron ore, limestone, coal, etc, it is also necessary that the designed pit contains ore which meets the customer's chemical specifications. This paper describes a technique of using linear programming for blending optimisation and the Lerchs-Grossmann algorithm (as in Whittle's 3D software) for pit optimisation in tandem, to achieve pit designs of targeted grade specifications.

Jan 1, 1996

Subsurface information from the "Upper Coal Measures" of the Sydney Basin is interpreted by means of structure contour maps, isopach maps and geological cross- sections. Particular reference is made to recent coal drilling operations by the New South Wales Department of Mines. The study is restricted to the onshore portion of the Sydney Basin.

Jan 1, 1972

By J F. C L Costa, J C. Koppe

The goal of this study is to characterise co-processed clinkers by identifying the most common minor elements, their distribution in the clinkers and possible effects on the mineralogical properties of the same. The results show the presence of an elevated content of transition metals, especially manganese concentrated in the matrix (up to three per cent) of the clinkers. Anomalous concentrations of arsenic have also been detected, especially at silicate crystal edges. The results indicate that the tracer elements can perfectly be associated to the mineralogical characteristics of the clinkers.

Jan 1, 2008

The Ravensworth-Liddell area is part of the Muswellbrook- Singleton Coal District of the Northern Coalfield. It lies in the Parishes of Liddell, Ravensworth, Vane and Howick, in the County of Durham, midway between Singleton and Muswellbrook, and is traversed by the Great Northern Railway, and the New England Highway.Ravensworth and Liddell railway stations are 57 miles arid 61 miles, respectively, north from Newcastle (Fig. 1).The area has been the centre of an intensive search for open cut coal during the past few years. More than 1,200 bores, of which about 10% were cored diamond drill holes, were drilled to depths of about 200ft. Portions with thicker cover have been explored by 10 diamond drill holes to depths of over 400ft. but core recovery from these deeper holes was poor, and the lack of detail in the recorded logs limits geological interpretation. The drilling has proved about 34,000,000 tons of open cut coal, and about 246,000,000 tons under deeper cover.GEOLOGYThe Ravensworth-Liddell area lies on the eastern flank and southern extremity of the Muswellbrook Dome, extending from Hebden in the north, to Jerry's Plains in the south, and the rocks under consideration belong to the Tomago Stage of the Upper Coal Measures. On the north they are truncated by the Hebden Thrust fault, which has a throw of about 4,500ft. (Raggatt, 1929). On the west they are bounded by outcrops of the Upper Marine Series, which conformably underlies the Upper Coal Measures, and...

Jan 1, 1953

By Paine G. G

The Red Dome Gold/Copper Mine is located approximately 15 km west of the township of Chillagoe which itself is approximately 220 km by road west of Cairns, Far North Queensland. The deposit, with other mines in the Mungana region, was worked from about 1901 to 1927. Exploration by Amoco Minerals Australia in the 1970s and early 1980s outlined a geological resource of 15 million tonnes. A mining reserve of 9.3 million tonnes was identified and originally developed by Elders Resources Limited. The mine commenced operations in March 1986 and was the first large-scale gold project in Australia to be developed solely on the heap leach process. The mine operated successfully as a gold heap leach operation until 1989 when new grinding, flotation and carbon-in-leach plant facilities were installed to process the non heap-leachable component of the orebody including the copper rich -ore. In March 1991, Red Dome Pty Ltd became a wholly owned subsidiary of Niugini Mining Limited. After six years of successful operation and having excavated a 200 in deep pit, it became evident in 1992 that unless more open cut reserves could be identified the operation was limited to six to nine months of high grade ore and a further 15 months of low grade stockpile material. A preliminary feasibility study was carried out to assess the viability of deepening the open cut. This indicated that from a technical and financial point of view it was possible to expand and deepen the open cut. This presented the daunting challenge of developing a 300 in deep, single access, open cut between a high chert ridge, a government railway line and a National Park. The meeting of this challenge is the subject of this paper.

Jan 1, 1994

By L H. Chapman, I J. Kelso, N H. S Oliver

Utilisation of modern 3D visualisation tools, can improve our ability to correlate between different datasets, and thus to produce more accurate geological models. Here, we present an application of such techniques to the Century Zinc Deposit, northwestern Queensland, Australia. This stratiform orebody is the second largest Zn resource in the world (167.5 Mt at 8.2 per cent Zn, 1.2 per cent Pb, and 33 g/t Ag). It is hosted in the Page Creek Syncline affecting Mesoproterozoic shales and siltstones of the Wide Supersequence of the Isa Superbasin. As in other deposits, (eg McArthur River, Lady Loretta, George Fisher and Dugald River), the mineralised sequence is bound by an important regional structure, the Termite Range Fault, which partly intersects the deposit along its Eastern side. This fault is thought have been active during sedimentation and probably also during mineralisation of the lowest part of the Wide Supersequence. The anastomosing geometry of this fault system and crosscutting relationships with other NE trending structures indicate that it was reactivated several times from Mesoproterozoic to at least late Devonian times (>1000 million years in total); as a result, the ore sequence is subdivided into several fault blocks.Using two different computer modeling packages (GOCAD and 3ds max), we have reconstructed and restored the stratigraphic horizon with the highest Zn content, realised a series of isopach maps for each mine scale stratigraphic unit, plotted the three-dimensional distribution of Zn, Pb, Ag, Fe and SiO2, and have begun to evaluate the degree of correlation between thickness changes and sulphide zoning. With this approach it is possible to better understand the timing of mineralisation from a genetic perspective, because the origins of the orebody are controversial. Three-dimensional reconstruction is a vital tool for identification of syn-sedimentary and post-sedimentary fault activity. In conjunction with sulphide precipitation, these are factors that greatly influence the stratigraphic thickness distribution. Post-sedimentary deformation can be recognised directly by core logging and pit mapping, but the effect of tectonic movements during sedimentation (growth faults in particular), that represents a substantial variable when we attempt to reconstruct basin evolution, is difficult to evaluate without this methodology. The 3D models improve our understanding of the local basin architecture, identifying similar grade characteristics at different structural levels and thus suggesting that much faulting and folding are post-mineralisation events. In addition, we identified several growth faults adjacent to thickened layers, representing two possible sedimentary depocentres. These thicker domains apparently relate to the highest Pb content. If further analysis of rocks, thickness and grade distributions support this preliminary correlation, then a syn-sedimentary model for mineralisation might be applied, and would contrast with the sub-surface model for mineralisation of Broadbent et al (1998).

Jan 1, 2003

By Caress ME, Knight MD

The eruption 75,000 y ago of the Younger Toba Tuff ignimbrite and associated ash-fall ranks as the greatest known volcanic event of the past million years. The ignimbrite is known to cover 21,000 km2 (it may extend farther under alluvium of the coastal plain) and forms a low-angle depositional shield centered on the Lake Toba caldera. The ignimbrite is largely nonwelded and shows systematic outward decreases in lithic and crystal contents and clast sizes. Coarse lithic lag breccias that occur at places 85 km apart point to two or more vents on a fissure having this length. The extensive associated ash-fall traceable as far as Malaysia and India is evidently a co-ignimbrite ash but could have a phreatomag-matic component. The Lake Toba caldera measures95 x 35 km and is >1 kn deep. It is not a single caldera but comprises several contiguous depressions and grabens diversified by two re-surgent domes. Earlier parts of the caldera are related to at least two earlier ignimbrites including the Older Toba Tuff dated by Chesner at 0.5 Ma. The caldera is elongated parallel to, and is only 25 km from, the great Sumatra strike-slip fault, and it can be considered almost certain that the caldera is in part a kind of pull-apart structure. The ignimbrites are very crystal-rich. There is no reason to think basaltic magma was involved in their emplacement. Together with ash-falls they have a total volume of several thousand cubic kilometers. They can be categorized as originating from partially crystallized granitic magmas that erupted because tectonic pull-apart occurred several times across the pluton. Small rhyolitic lava domes on fault-lines comprise the youngest volcanic products.

Jan 1, 1990

By Giannini L. M

A method using dynamic programming for solving the optimum pit limit problem was presented in an earlier paper. A recent issue of this journal contained some contributed discussion on the implementation of this technique. In this paper we provide some additional ideas and possible options one can incorporate into the method. In particular, an efficient procedure for obtaining further optimum pit outlines on extensions of the original block model is described.

Jan 1, 1987

In the new refinery, at the works of the Broken Hill Associated Smelters Proprietary Limited, situated at Port Pirie, South Australia, the refining routine is similar to that carried on in the old one in that bullion is progressively refined first for arsenic and antimony, then for copper and gold, then for silver, and finally for zinc. However, actual procedure differs in that each refining operation is now conducted continuously, whereas in the old refinery intermittent batch treatment was practised.The early experimental work was concerned solely with the development of the continuous desilverising process, which, in addition to continuous treatment, embraces the novel feature of conjugate solution formation with consequent production of a silver product relatively high in silver and low in lead.

Jan 1, 1932

By B Kretschmer, G Bartel, B de Villiers, W Watt

"The Nyrstar Port Pirie Smelter, located on the eastern shore of the Upper Spencer Gulf in South Australia 230km north of Adelaide, began operation in 1889 to process lead concentrate from the Broken Hill lead and silver mines. The site still operates an updraft sinter machine, commissioned in 1955, with the product fed into a blast furnace. While sinter plant technology has changed and improved since 1955, development has reached the stage where further enhancements are not possible or economic. High purity lead concentrates command lower margins and for the smelter to remain economically viable a wider range of higher value materials must be treated. The current flowsheet cannot meet this demand. Additionally, community blood lead levels particularly in children below four years of age, are a critical indicator used to measure the site’s environmental performance. The smelter’s environmental licence to operate is dependent on meeting future community and regulatory expectations. To achieve this a major step change in the emission performance of the smelter is required. Since 2008 pre-feasibility work has been undertaken to develop a new flowsheet and business model to allow Port Pirie to operate sustainably into the future. The main requirements were for the smelter to reduce lead and sulfur dioxide emissions that impact on the local environment and community to meet current and future environmental expectations, as well as dramatically reducing current feed constraints and change the business case from a marginal business to a sustainable profitable business. After reviewing all practical options a decision was made to replace the sinter plant with an Outotec Top Submerged Lance (TSL) furnace. This paper describes how the new furnace technology was selected and how it will be integrated into the present flowsheet; the unique funding arrangements that are in place to deliver the redeveloped site; and future opportunities that are associated with the implementation of the new flowsheet. CITATION: De Villiers, B, Bartel, G, Watt, W and Kretschmer, B, 2015. Nyrstar Port Pirie redevelopment, in Proceedings MetPlant 2015, pp 325–337 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 7, 2015

The Mammoth Copper Deposit consists of three distinct orebodies adjacent to the Mammoth Fault. This fault is arcuate, changing from a normal tension fault to a shear strike fault just to the north of the mine. Movement on the fault was probably contemporaneous with deposit- ion of the adjacent sediments. In the upper levels the No. 1 orebody occurs within a brecciated zone in the footwall of the fault, but at depth the No. 2 and 3 orebodies are stratabound by two brecciated lithologic horiz- ons. The host rocks are impure sandstones, arkoces and quartzites, which in the mine area are near the top of the Lower Proterozoic Myally Beds. Overlying these beds is a conglom- erate siltstone sequence which has been assumed to be the base of the Gunpowder Creek Formation. North and south of the mine the conglomerate rests on an erosional unconformity representing a major time break, but in the mine the uncon- formity and conditions of deposition of the conglomerate are obscure. Some mineralization is contained within the conglomerates. The sulphides present are chalcocite, bornite, chalcopyrite and pyrite. Chalcocite is dominant in the upper levels but could be en- riched by supergene processes. At depth, bornite becomes the dominant copper sulphide with lesser amounts of chalcopyrite, pyrite and primary chalcocite. Throughout the orebody minor digenite and covellite occur and arsenic is a minor constituent bound up with the pyrite. The bulk of the sulphides occur in stringers, fractures and breccia interstices but finer grained primary bedded sulphides can be observed. The genesis is probably a complex process in- volving active tectonic movements extending from deposition to post lithification giving numerous phases of brecciation and redistribut- Ion.

Jan 1, 1974

With the proclamation of the Environmental Protection Act, 1971-80, the Environmental Protection Authority and Department of Conser- vation and Environment were established to enhance the quality of the environment. Proposed gold developments of all scales can be referred to the Authority in the form of a Notice of Intent. Environmentally significant projects might then require preparation of an Environmental Review and Management Programme. Current environmental issues include the'effects of clearing by prospectors,, mine dewatering and tailings disposal. INTRODUCTION In the past, the environmental aspects of gold industry related activities have received little attention. However, with the proclamation of the Environmental Protection Act, 1971-80, mechanisms were instituted which allowed both for referral of projects to the Environmental Protection Authority (EPA) and establishment of the Department of Conservation and Environment. As well as providing assistance to the EPA on referred projects, the Department is concerned about a number of environmental issues associated with the gold mining industry.

Jan 1, 1982

By K Watters

API Management Pty Ltd (API) is currently developing the West Pilbara Iron Project (the ‘Project’). The Project is a substantial greenfi elds mining and infrastructure development proposed for the west Pilbara region of Western Australia. The Project will establish API as a new and independent supplier of direct shipped iron ore. API manages the Australian Premium Iron Joint Venture (APIJV) on behalf of joint venture participants Aquila Resources Ltd and American Metals and Coal International Inc. The APIJV was formed in February 2005 with the objective of developing a long-term iron ore export operation in the west Pilbara region.Development of Stage 1 comprises a 30 million tonne per annum (Mt/a) channel iron deposit (CID) operation scheduled to commence in the second half of 2014 subject to approvals. JORC compliant CID resources total nearly 700 million tonnes and the Stage 1 mining area comprises eight iron ore deposits located between 30 km and 85 km south of Pannawonica. Run-of-mine ore from the eight deposits is transported to a central processing facility for crushing, screening and blending into a sinter fines product, which API has named West Pilbara Fines or WPF. Construction of a 282 km main line heavy haulage railway from the Stage 1 mining area to the proposed greenfields multi-user port at Anketell Point near Wickham, is capable of accommodating large Capesize bulk carriers and providing export facilities for other third parties. Capital investment in the order of $A6 billion includes essential support infrastructure including power, water, accommodation, roads and an airport at the mine.A feasibility study for the development of the Stage 1 mine, rail and port infrastructure has been completed along with environmental surveys of the mine, rail and port areas with Public Environmental Reviews (PERs) for each submitted for public review by end 2010. Consultation and cooperation with various stakeholders of the Project areas, and early engagement with traditional owners of the respective areas has commenced. Various sampling and metallurgical characterisation programs combined with independent institute and steel mill based testing have confirmed the positive sintering characteristics of WPF ore, which is higher in alumina (3.37 per cent) than typical Pilbara ores. *This is an abstract only. No paper was provided for this abstract.*

Jul 11, 2011