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The information requirements of the Australian Stock Exchange Ltd for listing and reporting seek to ensure that the market is fully and correctly informed in a timely manner. This discussion confines itself to the technical reports from mining companies required for prospectuses, information memorandum, quarterly, annual reports and any other announcements to the Exchange. The Exchange requires that technical reports are produced by suitably qualified and experienced personnel and, in the case of a company listing, that these personnel have no interest in the company to be listed. Further, the Exchange has draft prospectuses reviewed by other independent suitably qualified and experienced personnel.

Jan 1, 1987

By J Walasiak

In the climate planning of mines and tunnelling with anticipated poor climatic conditions, and especially in case of longer working shifts, the main question is whether it can be reliably prevented that certain climatic limits laid down be exceeded. Working at high temperature and/or humidity can lead to reduced human working energy û a very important economic aspect û and to a risky lack of concentration on the part of the miners or to heat collapse and extremely dangerous heat stroke. With the Deutsche Montan Technologie GmbH (DMT) climate prediction programs, both the dry and the extremely significant humid heat transfer can be calculated. This is due to the high planning reliability involved. With the help of these climate prediction programs it is already possible to determine the anticipated climatic values for the operation phase as early as the planning stage of new ore or coal fields or of tunnel construction projects and to design the optimum air cooling system for every underground project with due regard to technical and economic aspects.

Jan 1, 2005

Maintaining and improving the economics of open pit mining in the future requires understanding of the characteristics of open pit mining that are different to other mining or business activities, designing mines in the first place to be less susceptible to changes in these important characteristics, and adopting strategies which yield reliable returns despite unforeseen change. Planning and production personnel require guidelines and performance standards that are based on sound economics not solely on production criteria. The guidelines adopted for long-term implementation must assume a declining price for mineral products along with declining real costs, with research efforts directed at development of both evolutionary and revolutionary ideas aimed at implementation. Decision-making must focus on risk and probability criteria rather than just simple return-on-investment criteria, and the approach for management of personnel must support the higher level of communication essential for fast decision-making in the new environment of continual change.

Jan 1, 1992

The paper examines the current status of risk and accepted practice in mining geomechanics. It explores some deficiencies in human capital, risk analysis and our future technical needs, and suggests ways of improving our estimates of slope reliability through knowledge sharing and research.

Jan 1, 2003

In the late-1990s, and into the 2000s, many industries, including the mining industry, have seen significant transaction activity by way of acquisitions, floats, joint ventures and major capital projects. The fundamental financial trends are two-fold. First and foremost, a high level of transaction activity within the industry and secondly, the recently introduced requirement for corporate governance standards, have placed increasing pressure on the directors of mining companies. This paper will deal with specifically corporate governance implications of any large capital investment transaction and the associated impact on the mining industry. To provide the framework for this paper, I have looked at a number of recent transactions as well as corporate governance recommendations from the ASX and the HIH Royal Commission.

Jan 1, 2003

The truly scientific method in the study of such questions at the present day is the reverse of that which was followed in the early days of geology, when after the observation of a few isolated facts, some great geological mind was led to a general theory, and humbler followers were only too apt to do mild violence to nature in order to make her facts conform to it tt accumulates year after year a multitude of facts of patient observation, supported by studies with the microscope, and in the laboratory, avoiding general theories, and only making such deductions in regard to locftl conditions as are supported by the overwhelming evidence of facts. S. F. Emmons, on the geological distribution of minerals in the United States, at the "world's congress" of mining engineers, Chicago. Fig. l.-This exhibits the general stratigraphical characters of the southern lodes. The" Indicator" veins, the great barren lode masses, a later fissure than all of these (" B "), and the auriferous lodes of last series cleaving the wrinkled terraces and the older lodes also are" Indicator" veins. B is a later formed vein that leaves no " depositions" behind. ooe are fragments of the" most ancient'' lode wreckage. Db are the auriferous lodes and correspond with those lodes, also whose auriferous characters are not result of secondary impregnations.

Pressures are foreseen for departments of metallurgy to make. radical changes in their undergraduate curricula. The curricula need to be made more attractive to high'school students in -order to increase the number of enrolled students. The distinctive character of extractive metallurgy needs to be emphasised to resist encroachment by chemical engineering. There should be content relevant to each of the professional functions and, particularly, to' society's broad expectations of metallurgists. Content, teaching methods, etc. need to be acceptable to women, mature-age -students, Aboriginals, and other groups, as well as young white males. Learning experiences should be negotiable by the students in response to the advent of learning packages delivered via personal computers. All of these needs could be satisfied by a radical change. in attitudes and objectives during the design; implementation and evaluation stages of . a new type of curriculum, using a wide range of problem-based learning experiences..

Jan 1, 1986

Simulation and animation models have developed rapidly over the past decade. Even so, the current state-of-the-art can be viewed only as being in a state of continual development with improvements in both hardware and software constantly being

Jan 1, 1998

By C Riley, N Davies, J Carpenter, I Lipton

Nautilus Minerals Incorporated (Nautilus) recently announced the worldÆs first Seafloor Massive Sulfide Mineral Resource at Solwara 1 in the Bismarck Sea, Papua New Guinea . The discovery, exploration and resource modelling of this æblack smokerÆ system located 1500 m under the sea involved unique technological development. Whilst the resource estimation methodology had similarities with approaches adopted for analogous volcanic-hosted massive sulfide (VHMS) deposits, specific parts of the resource estimate called for new ways of assessing data. This paper discusses several innovative methods for collecting and assessing Solwara 1 exploration data. This ia an ABSTRACT only. A full-length paper was not prepared for this presentation.

Jan 1, 2008

Differences in the assay results of replicate samples engender doubts on the reliability of ore sampling and of assaying procedures. An analysis of variance is a technique to estimate the variability at each level of the procedures. In an example, the variability of one-metre core samples was far greater than that of the assaying technique.

Jan 1, 1976

By Parsons AE, Lewis IE

Selenium is a minor constituent of the raw materials processed by the Cockle Creek smelter of Sulphide Corporation Pty. Limited. Certain proposed raw materials contain higher levels of selenium, and these will create a problem with regard to the composition of liquid effluent discharged from the smelter. A method has been developed for removing selenium from the smelter circuit by the sulphation of the fume collected in the Acid Plant electrostatic-precipitators. It is planned that by treating 10-20% of the total dust arisings there will be a substantial reduction in the levels of selenium reporting in effluents when treating selenium-bearing raw materials. The selenium is recovered in elemental form.

Jan 1, 1978

Jan 1, 2004

Seven papers included in Session 8 of the Third International Mine Water Congress under the heading "Achievements in Mine Water Management & Research" have been reviewed. Only one paper, a case study by Masters on biological treatment of inorganically polluted effluent, has any connection with research in the sense of seeking new, generally applicable knowledge which would advance the frontiers of mine water management. The remainder deal with various aspects of the management of mine water ranging from investigation of the geology of a specific aquifer system through operating dewatering systems to the management of specific effluent disposal problems.

Jan 1, 1988

New Zealand China Clays operata a plant at Matauri Bay, Northland for the benefaction of hallosite clay. Production is several thousand tonnes per year of which about ten per cent per year is supplied to an expanding export market.

Jan 1, 1978

The Fraser Range is composed dominantly of basic pyroxene granulites derived from basalts, many of which appear to have been vesicular and*pillowed. Acidic and basic garnet-bearing granulites are important in the west, and acidic granulites and narrow anortho- site layers are dominant in some regions east of the Fraser Range. An extensive flat-lying olivine gabbro sheet cuts the granulites, and in places has been converted to spinel-bearing meta-gabbros and pyroxene granulites. The granulites of the Fraser Range (Proterozoic) are separated from the gneisses and schists of the Goldfields regions (Archaean) by the Fraser Fault, over which there is a large gravity anomaly (gradient 20 milligals per mile). Some of the problems associated with the concentration of Cu, Ni, etc. liberated from mineral lattices during metamorphism, and other principles of metal concentration in granulite terranes, are discussed. The recognition of vesicular and pillowed zones, even though highly metamorphosed, is of fundamental importance.

Jan 1, 1969

Close spatial relationships between the deposits of the Etheridge Goldfield (23,000 kg of bullion) and various regional geological and geophysical features suggest that genesis of the ore deposits was a multi-stage process that started with magmatic and metamorphic stages in the mid-Proterozoic, climaxed with structural and hydrothermal stages in the late Palaeozoic and terminated with an oxidation enrichment stage in the Cainozoic. Acceptance of this hypothesis permits classification of the Georgetown region into areas likely to contain deposits of the Etheridge type and those unlikely to do so. Consequently there is little scop- for the discovery of extensions of this field. However, the stratigraphic interval between the source rocks of the Etheridge field and stratigraphically higher host rocks of the Croydon field may contain disseminated replacement gold deposits of the Carlin type. The potential host (pyritic carbonaceous, and locally dolomitic siltstone of the Candlow Formation) is locally faulted and cut by granitoids and the extension of a mineralised, long-standing zone of structural weakness.

Jan 1, 1980

By J Abols, T Hughes

The selective recovery of gold and silver from solutions containing other metals, such as copper, is possible using AuRIX«100 resin in conjunction with the Gekko Resin Column. Selectivity is driven by controlling the solution pH, which enables activities such as loading copper, gold and silver and then selectively stripping copper before gold and silver. Alternatively gold and silver can be loaded and the copper left in solution. The selective loading of gold while reducing the silver loading has also been demonstrated, opening the possibility of producing high grade gold dorT from high grade silver pregnant leach solutions. This paper reviews the AuRIX«100 resin and Gekko Resin Column Technologies, discusses the uses of AuRIX«100 in the recovery of gold and silver and the chemistry relating to several projects for which AuRIX«100 is being tested.

Jan 1, 2005

BHP BillitonÆs Yandi channel iron deposit has a large resource of approximately 1.3 billion tonnes. This is a bulk mining operation with a high degree of selectivity not being practical. In contrast the deposit geology is a complex interrelationship of primary channel facies, secondary enrichment of iron and a secondary redistribution of the major contaminants. These variations in geology and alteration can occur over ranges of hundreds of metres down to knife edge contacts. In addition, differences in primary facies and mobility during alteration often result in the iron and contaminants having different patterns of enrichment and depletion. Despite the scale of these operations, if the geological domaining is not optimal, significant errors in the resource estimate of grades and tonnage will occur. Getting the geology right has become a common clichT among mining professionals. However, in many situations, obtaining optimal geological domains for resource modelling is best achieved when there is input from geology, statistics and geostatistics. In this paper, moving window statistics are utilised to see through locally high variability to identify trends that assist in locating difficult to identify geological boundaries. After the creation of geological domains, univariate and multivariate statistics and principal component analysis assist in validating and characterising geological domains. Finally, variography and domain contact analysis are used to analyse the nature of the boundaries between geological domains. At the Yandi channel iron deposit, the inter-relationship between geological and geostatistical analysis has resulted in significant improvements to geological domaining and the treatment of domain boundaries during estimation of iron and contaminates.

Jan 1, 2005

By T P. Hynes

Submarine tailings disposal is conceptually an attractive option for managing reactive mine wastes in coastal regions by virtue of reduced sulfide oxidation under a water cover and no infrastructure to maintain after mine closure. However, the lack of detailed knowledge of metal leaching, dispersal of fine tailings and biological impacts in the marine environment has led to no operating permits currently in effect in Canada. Detailed chemical and ecotoxicological assessments at two historic copper mine sites (Little Bay and Tilt Cove) in the north coast of Newfoundland with tailings disposed in an estuarine to shallow (=100 m) marine environment have demonstrated reduced reactivity of sulfidic tailings when submerged under water. Only non-acute toxicity is detected in biota inhabiting the immediate vicinity (A review of another historic shallow marine tailings operation in the southern tip of Vancouver Island (Jordon River) with a high-energy setting also reveals problems with unconfined tailings dispersal and temporal biological impacts. Documented studies at two deeper (140 - 360 m) marine tailings disposal operations at the northern tip of Vancouver Island (Island Copper) and northwestern coast of British Columbia (Kitsault) again illustrate imperfect predictions of tailings re-suspension and dispersal. At these sites, bioaccumulation of tailings-derived metals appears to be minimal. There is evidence of rapid re-colonisation of the tailings surface by benthos but of different species than the original population. Integrating these observations with reported metal fluxes and biological diversity associated with submarine hydrothermal vents, the risks and benefits of deep-sea (>1 km) tailings disposal are discussed. To determine if submarine tailings disposal in deep, confined basins on the seafloor is environmentally friendly, detailed multi-disciplinary research incorporating physical, chemical, biological and toxicological components will be indispensable.

Jan 1, 2003

An empirical kinetic model is discussed that enables the number of stages in a carbon-in-pulp plant and the amount of carbon in each stage to be calculated for any desired metallurgical performance. It is shown that a knowledge of the kinetics of gold extraction by activated carbon in each stage assists plant operators in the important' areas of process control and optimization. Factors such as mixing efficiency, concentration and distribution of carbon through the plant, bypassing of pulp through a stage, and carbon poisoning are examined. The resin-in-pulp process for the extraction of gold cyanide is also discussed, and the chemistry of absorption and elution on strong- and weak-base resins is examined. In addition, operating results from a small-scale resin-in-pulp pilot plant are presented, and various applications in which resin-in-pulp may be preferable to carbon-in-pulp are discussed.

Jan 1, 1982