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In this year marking the centennial of the Geological survey of Western Australia, it is appropriate that we should review the value of the contribution of the Survey, and Australian Geological Surveys in general, to the exploration industry. Most geological surveys in Europe and North America had their origins in the first half of the 19th Century when the burgeoning Industrial Revolution was demanding the identification of new sources of coal and iron ore. Australia, as a young nation, essentially dependent on an agricultural and pastoral industry, and with already discovered vast coal resources in Eastern Australia, had, no great need to explore for new mineral resources. However, with the discovery of gold in 1851, the mineral potential of the country became apparent to the whole world and the first Geological Survey in Australia was set up in 1852 in Victoria under A.R.C. Selwyn. After a number of false starts all Australian States had an established Geological Survey by 1900. It is hard to assess the contemporary value of the early work of the Geological Surveys with respect to exploration, almost all major mineral discoveries were made by prospectors and most mining companies had little time for geologists - although the Chamber of Mines in Western Australia in 1910, did recommend that the Geological survey be granted an additional ten thousand pounds over two years to map all existing goldfields and the country between them, and produce a reconnaissance map of the area east of a line between Wiluna and Edjudina as far as the South Australian border!

Jan 1, 1988

By West RF, Pooley RH

An underground mine, a treatment plant and supporting facilities have been constructed at Lebong Tandai in Sumatra, Indonesia by PT Lusang Mining. Throughput is initially 50,000 tonnes per annum of ore with an inbuilt capability to expand to 100,000 tonnes per annum. Construction proceeded in parallel with design work on a tightly controlled critical path schedule. The very remote location of the mine, the difficult access and the fact that equipment was imported from many parts of the world presented a challenging project management problem. The transport system, which involves road, river and rail and support facilities on site had to be brought into full operation prior to the arrival of major equipment. Mine development involved the reopening of the old access drives and workings, refurbishing two shafts and the haulage system together with redevelopment of old stoping areas and the opening of new stoping areas. Ore production is now from three main areas using shrink and underhand stoping methods. Ore breaking and drive development is with conventional airleg mounted rockdrills and ANFO explosives. Exploration to locate and develop new reserves to replace ore mined is an ongoing activity.

Jan 1, 1986

By Moy A. D

The Esperanza deposit is located 120 kin N of Mount Isa, Queensland at approximately lat 19¦20'S, long 139¦22'E on the Camooweal (SE 54-13) 1:250 000 scale map sheet. It is one of several structurally controlled copper ¦ cobalt deposits developed along the Mount Gordon Fault zone and related faults, within the Western Fold Belt of the Mount Isa Inlier (Figure 1). Together with the nearby Mammoth orebodies it forms the basis of the Gunpowder operation of Aberfoyle Limited. Until recently ore was mined from the Mammoth orebodies by open stoping with decline haulage to surface leach pads. Leaching of in situ broken ore (in place) and surface heaps, followed by solvent extraction and electro-winning (SX-EW), produced copper metal on-site. In March 1997, mining was suspended at Mammoth and the focus of the Gunpowder operation switched to development of the Esperanza orebody, which is expected to begin open cut production in mid 1998. SX-EW methods will produce 44 000 tpa of copper from an expanded plant. The pre-mining mineral resource at Esperanza (measured, indicated and inferred) is estimated at 4.6 Mt averaging 7.7 per cent copper.

Jan 1, 1997

The efficient design of carbon-in-pulp (C.I.P.) plants involves the integration of both process engineering and design engineering.Many recently constructed plants have not recognised the above interrelationship, and as such have incurred higher capital and operating costs than were in reality necessary. This has been compounded in some cases by slavishly following the design of plants where process conditions are different for the ore characteristics in question, thus perpetuating design errors that finally become industry "accepted practice".In the paper that is to be presented the unit operations of crushing, grinding, classification, leaching, adsorption, desorption and electrowinning in C.I.P. plants will be discussed with reference to the integration of process and design engineering.

Jan 1, 1986

By T Weldon

In the last 15 years, it has become increasingly popular to win gold and silver from carbon strip solutions with electrolytic æsludgeÆ cells. The precious metal sludges produced in the cells are washed to the cell bottom and pumped into filters. Most new operations are specifying sludging cells, and many older operations are being retrofitted with up-to-date electrolytic sludge cells and filters. The new sludging cells are generally more energy efficient than older cells, but more importantly, the cell operations to remove product are much less labour intensive, cleaner, and the operator need not have physical contact with the electrolytically produced metal. A case study of a major North American gold producer (50 000 kg/yr) that removed old style stainless steel wool cathode cells and installed new sludging cells and sludge filters is presented. The effect of various impurities is discussed.

Jan 1, 2005

By G Barla

In Europe, a major interest in the infrastructure and tunnelling fields is in the new crossings of Alps in the form of base tunnels, which are important components of the high-speed (for passengers)/high-capacity (for freight) Trans European railway corridors. These tunnels cross the mountain belt at the elevation of the main cities and basins located all around the Alps and are longer (up to 57 km) and deeper (up to 2500 m) than all tunnels constructed in the centuries before. The excavation of the first Alpine railway and road traffi c tunnels could in general be carried out successfully by conventional excavation methods. With the great lengths of the new base tunnels, mechanised excavation by using tunnel boring machines (TBMs) is imperative as it contributes significantly to savings in construction time and costs. Questions are however posed on the adoption of such a systematic tunnel construction method given the severe ground conditions which are some time anticipated along the tunnel alignment, with possible major geological hazards such as water inflow in heterogeneous fractured or karstifi ed rock masses, stress-induced tensile failure of hard rocks, and plastic shear failure and squeezing of weak rocks, etc. This lecture is to briefly review the current state-of-the-art in the understanding and modelling of two such critical hazards as spalling/bursting and squeezing ground behaviour. With the present interest in the design of mechanised tunnelling with TBMs in such conditions, the complex interaction between the rock mass, the tunnel machine and its system components, and the tunnel support is studied in detail by numerical modelling. The research and development efforts presently underway with the intention to provide the designer with a novel three-dimensional (3D) simulator of mechanised tunnel excavation are presented. Case examples are discussed with reference to the Lyon-Turin Base Tunnel design.

Mar 8, 2011

The Mineragraphic Section of the Council for Scientific and Industrial Research has had occasion from time to time to examine rocks, ores and concentrates from the Yatukoula goldfield, Fiji. The results of the examinations have been supplied as Mineragraphic Reports and have been supplementary to various investigations carried out by the mining companies on ore treatment, or by visiting geologists on the nature of the rocks and lodes. The presence of tellurides was determined in 1935, though incorrectly as nagyagite. The general absence of lead, except in traces, was soon afterwards discovered, and it came to be recognised as the mines were opened up that the chief telluride minerals on the field were sylvanite and native tellurium. Specimens of the tellurides have been provided from time to time by E. G. Theodore, Managing Director of the Emperor Mines Ltd., and of the Loloma (Fiji) Gold Mines N.L., and further material was recently obtained, as the result of a visit to the field at the invitation of Mr. Theodore.The aim of this paper is to describe the occurrence of the tellurides in these specimens. The work has been carried out as part of the programme of research of the Mineragraphic Section.THE VATUKOULA GOLDFIELDThe Emperor, Loloma and Dolphin mines are situated at Vatukoula, six miles, south of Tavua, on the north coast...

Jan 1, 1949

By P Hollings, J Holliday

Porphyry copper, gold and molybdenum deposits form in subduction-related settings in association with calc-alkalic or alkalic magmatism. Hydrothermal alteration assemblages are zoned, with potassic cores and propylitic haloes overlain by extensive domains of clay alteration and silicification (lithocaps). Copper sulfides, gold and molybdenite typically occur in veins or hydrothermal breccias, and less significantly as wall rock replacements. Epithermal deposits may form above or to the side of porphyry systems, and may be juxtaposed into the core of a porphyry deposit if rapid uplift and exhumation occur through the life of the magmatic-hydrothermal system. Volcanichydrothermal breccia pipes (ædiatremesÆ) commonly form late in the life of a porphyry system. They may contain clasts of porphyry-style mineralisation, and can host significant epithermal gold resources. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Percival T. J

Precious metal deposits containing fine-grained disseminated or dispersed gold-silver form by reactions between metal-bearing hydrothermal fluids and sedimentary host rocks. Host rock permeability and chemical composition exert a primary influence on the fluid movement necessary for any primary dispersion halos to form around ore bodies, and determine whether a disseminated style orebody itself will even form. Where the mineralized rocks are relatively unfractured the margins of the orebodies exhibit abrupt decreases in gold content, and strong corresponding decreases in the contents of other metals. Primary dispersion patterns of this type are difficult to recognize and commonly are only a few meters (or less) in width. If the host rocks were well shattered and broken before mineralization, remnant amounts of the hydrothermal fluids may be dissipated in fractures lateral to or above the ore zones. This causes geochemical anomalies to form with clays and silt- size silica within the fractures over distances of up to at least 30-50 meters away from the main orebodies. The tendency for large primary dispersion halos not to form around these deposits explains the disappointing results from so many drilling programs where no multi-gram gold-grade material was even found: if large areas and apparent large volumes of rock contain one gram or less gold that likely is the "orebody" and not a halo effect around high grade mineralization.

Jan 1, 1988

By M I. Pownceby, S P. Suthers, V Nunna, G J. Sparrow

Global demand for iron and steel has increased substantially over the past 20 years and there has been a greater focus on developing suitable processing options to treat low-grade hematite-goethite ores containing higher levels of silica and alumina impurities. The processing applicable to reduce the impurity levels in these lower-grade iron ores depends on their mineralogy and a thorough understanding of the process dynamics associated with the separation technology. Different separation technologies used to remove silica and alumina from low-grade iron ores were reviewed. The major concentration methods that may be applied to upgrade lower-grade lump iron ores include magnetic separation, wet and dry heavy media separation, and air-pulsed jigging. The technologies applicable to beneficiating iron ore fines include wet and dry gravity and magnetic separation, flotation, and roasting followed by magnetic separation. It is necessary to investigate the application of separation technologies on a case-by-case basis to select economically viable beneficiation strategies suitable for the particular low-grade iron ore. A commercial flow sheet is expected to involve the implementation of several separation technologies.

Nov 8, 2021

The Yabulu refinery of Queensland Nickel Pty Ltd located near Townsville now imports more than three million wet tonnes per year of nickel laterite ore from New Caledonia and Indonesia, making it the largest importer of any commodity in Australia. The project has illustrated that importing untreated bulk ore and re-exporting high value products makes good economic sense for the company and the nation. The economics of this exercise have been considerably enhanced in the past year by changing the project's principal product from nickel oxide sinter to refined high purity nickel metal. It is one of the few operations in the world where nickel ore is transformed to nickel metal at a single site. Several novel technological processes were developed at Yabulu and incorporated into the refinery to allow this product transition to occur. By utilising internally developed technology the new processes were installed at a capital cost of less than $10 million. It is unique for a large nickel producer to completely change the quality of its entire product range many years after the plant was constructed and considerable attention to marketing the new products has been required.

Jan 1, 1995

By Wygralk A, Hallenstein CP

On a world scale, many Mid-Proterozoic fluvial sediments are prospective for low grade, large-tonnage gold deposits. A significant area of the Northern Territory is covered by such Mid-Proterozoic sediments, the gold potential of which has been barely tested. The geological knowledge of these sediments is summarised. The Westmoreland Conglomerate, the basal Mid-Proterozoic formation of the McArthur Basin, has been subjected to detailed sedimentological studies in order to determine the paleoenvironments and to assess the possibility of paleoplacer occurrences. The results indicate that the sandstones and conglomerates of the formation were deposited by braided rivers and debris flows as an alluvial fan which originated in source areas to the north east. The formation contains several upward-fining cycles of sedimentation, which are related to repeated periods of uplift in the source areas. The formation of placer-type gold occurrences is possible in such depositional environments. Very limited heavy mineral sampling has indicated a cassiterite- wolframite-gold suite in the sediments of the Westmoreland Conglomerate. Disconformities at the base of sedimentation cycles are deemed to be the most likely sites for large-tonnage paleoplacer concentrations.

Jan 1, 1984

By Ngai WCT

Over 90 per cent of the explosives in Hong Kong are used in civil engineering works. The Hong Kong Government controls all explosives and delivers on a daily basis to each site which it has licensed. Such deliveries need to be arranged the day before actual delivery. With the vagaries of the traffic in Hong Kong, contractors do not necessarily know the time of arrival of explosives. Contractors in general would like to reduce their exposure to these potential delays and the high cost of explosives deliveries. The high population density and urbanisation means that rock blasting has to be carried out in close proximity to other property. In order to protect life, property and utilities, it is not only necessary to employ proper blasting techniques but also to adopt effective safety measures. The Route 3 Advance Earthworks project is located on the north-west corner of Tsing Yi Island, Hong Kong. It is one of the Airport Core Programme projects for the new Chek Lap Kok Airport. Secured by Leighton Contractors (Asia) Ltd in early-1992, the work commenced in May of the same year, with completion and handover to the Hong Kong Government in May 1995.

Jan 1, 1995

By J de Vries

Arthur Page, a past President of AT&T said:All businesses in a democratic society begin with public permission, and exist by public approval. Product stewardship in its most basic form is simply risk management applied to the products we produce. Conceptually it may be considered as a more expansive approach to many existing safety, heath and environmental programs. Key differences include the extension of responsibility beyond the direct control of management, and consideration of the implications your products and processes have on the broader community, as opposed to the confines of an individual mine site or operation. This paper reviews the processes used by Orica Ltd to manage its product stewardship program. OricaÆs product stewardship program is expansive and supports activities and business that range from manufacture and delivery of commercial explosives and sodium cyanide to mines throughout the world, supply and operation of municipal water facilities, and manufacture and distribution of consumer products such as household paints and adhesives. We highlight the development of the program through experience both good and bad, and by use of case studies to illustrate how an active product stewardship program is an effective business risk mitigation strategy.

Jan 1, 2006

Benchmarking of mining operations has been in vogue for a number of years: it seems teams are forever flying around the world to try to understand what other operations are doing. However, unless a benchmarking exercise involves data gathering at a fundamental level and a rigorous analysis process is applied, the trip will be nothing more than industrial tourism. When benchmarking is performed thoroughly, the range of comparisons that can be made is extensive and informative, and need not be restricted to sites with similar conditions and equipment fleets. This paper describes the detailed and rigorous process for benchmarking used throughout AMC benchmarking studies. The paper demonstrates how, through drilling down to the underlying drivers, the often heard cry of æyou canÆt compare us, weÆre differentÆ can be overcome. Included in the discussion are a number of significant issues that have been identified during AMC benchmarking studies. The paper then considers the types of opportunities that have been identified and the potential for improvement. The paper concludes with a discussion of the implications for planning, measuring and management of operational performance.

Jan 1, 2003

By R Ulusay

Rock mechanics involves characterizing the mechanical properties and behaviour of rock material and the natural discontinuities of the rock mass, while rock engineering is concerned with specific engineering circumstances, for example, how much load will the rock support and whether reinforcement is necessary. Rock engineering models developed depend considerably on the input data such as boundary conditions, the properties of rock material and rock mass. Correct evaluation of these properties frequently requires laboratory and in-situ tests, supplemented with a high degree of experience and judgment. Accordingly, since 1974, the ISRM Commission on Testing Methods has spent considerable effort in developing a succession of the ISRM Suggested Methods (SMs) for different aspects of rock mechanics and rock engineering with the contribution of a number of working groups and cooperation of some other ISRM Commissions. This paper emphasizes the need and importance of standardization of rock testing methods within the context of the ISRM SMs, gives a guideline for developing ISRM SMs and finally discusses on some implementation and contractual issues associated with rock testing and experienced in practice, and briefly introduces main future trends in rock characterization, testing and monitoring. This is an extended abstract only. CITATION:Ulusay, R, 2018. Standardisation on rock characterisation, testing and monitoring with emphasis on ISRM suggested methods, practical issues and difficulties, and future trends, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 17–18 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By Belton G. R

The kinetics of the interfacial reaction of H2O on liquid silica-saturated iron silicates has been studied by means of measurement of the HDO-H2 isotope exchange reaction. The apparent first order rate constant, ka, was found to be inversely proportional to the H20/H2 ratio, consistent with two electron (melt to adsorbed/dissociating molecule) transfer mechanism and can be given by the expression In ka = -1.97 x 104/T + 1.57 - ln(pH2O/pH2), where the units for ka are mol cm -2 s-1 atm 1. The results of the current study are shown to be consistent with the indirect measurements of earlier work.

Jan 1, 1987

The emerging discipline of ægeometallurgyÆ is not new but is becoming increasingly recognised as a discrete and high-value activity that reflects an ongoing commercial and cultural trend towards more effective mine site integration and optimisation. The AMIRA International P843 æGeMIIIÆ project (Geometallurgical Mapping and Mine Modelling) is a major new cross discipline research collaboration designed to provide support for this emerging industry trend. The project is currently supported by 18 global mineral companies and involves collaboration between the CODES Centre of Excellence (University of Tasmania), JKMRC and BRC (University of Queensland) and CSIRO Exploration and Mining. These groups represent recognised research excellence in the fields of economic geology, automated core logging, advanced microscopy and process mineralogy, mineral processing, mine planning and resource optimisation. The needs and challenges of geometallurgy as an integrated activity will be outlined together with the ongoing contribution and aims of the AMIRA P843 æGeMIIIÆ project. The main emphasis is on development of predictive geometallurgical indices for key processing performance parameters that reflect inherent geological variability. The ultimate aim is to provide predictive indices of geometallurgical performance that can be confidently embedded into resource models and used for risk-defined mine planning and optimisation.

Jan 1, 2008

By J Canterford

Although we have access to a wide range of sophisticated process design and improvement tools in combination with a significant range of case studies, the mineral resource industry still manages to be plagued by the negative publicity surrounding operating plant failures because they were neither smart nor safe, together with proposed projects that fail at the first or second hurdle. The general public and the finance industry are generally totally uniformed about projects that ramp-up to name plate capacity on time and on budget and even more so when ahead of schedule and under budget. As the saying goes, good news does not cut the mustard.The following is a summary of the author’s sometimes jaundiced view about why metallurgical plants do not live up to their technical and commercial expectations. In no way should the summary be construed as a negative reflection on the skills of the metallurgical profession. Rather, it is to be taken as a positive acknowledgement of those skills and is intended to highlight some of the major considerations that need to be assessed as a potential project transforms into a sustainable technical and commercial reality.While a considerable portion of the summary is directed at developing hydrometallurgical flowsheets, the general principles are equally important to all aspects of extractive metallurgy.For convenience, the summary covers the following five basic discussion points – project, people, process, patents and politicians.

Aug 8, 2011

By Harper F

This paper outlines the authors' views of the methodologies which can be employed to value mineral properties at different stages of development for the purposes of project financing, mergers and public floats. This paper discusses the key issues in Discounted Cash Flow (DCF) analysis including the importance of data verification and the shortcomings in DCF analysis. Stockmarket valuation measures and valuation methodology for exploration and pre development projects are examined through examples and pitfalls are identified. The use of valuations in corporate transactions and their strategic value is also discussed.

Jan 1, 1994