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By J R. Kyle

The Deep Mill Level Zone (DMLZ) skarn Cu-Au deposit is the deepest explored part of the Ertsberg East Skarn System extending from the surface at 4200 m elevation to the DMLZ at 2900 to 2600 m. The DMLZ is hosted in an upper Cretaceous to lower Tertiary siliciclastic and carbonate succession adjacent to the 3 Ma Ertsberg pluton. Much of the DMLZ ore is hosted by mixed assemblages of siliciclastic and dolomitised carbonate strata that have been altered to Mg-rich skarn assemblages. Unaltered equivalent strata from a 300 m cored interval in the Yellow Valley Syncline were characterised petrographically and representative samples were analysed for major element compositions. These stratigraphic and chemical units are interpreted to be responsible for the varying skarn lithologies within the DMLZ. The dominant prograde skarn assemblages are controlled by protolith composition, notably the relative abundance of quartz, dolomite, and calcite within the protolith. Models based on isochemical metamorphism of mixed assemblages of quartz and dolomite suggest that the formation of the forsterite-diopside dominant skarn assemblages resulted in the greatest amount of pore space increase. DMLZ Cu-Au concentrations were locally controlled by host lithology, with structural features providing fluid pathways that focused the mineralising fluids. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

The extraction of world-class mineral deposits using massive underground mining techniques is not an entirely new theme to world mining companies and experts. Previous MassMin conferences have helped to gather and disseminate the valuable experience and knowledge so important for the proliferation of safe and efficient mining of large underground deposits. With the passing years since the first MassMin conference in Denver in 1981, a number of factors have contributed to an increase in massive underground mining around the world, including environmental pressures, gradual exhaustion of shallower deposits and the enabling effects of improving technology in disciplines related to underground mining. Massive underground mining is heading deeper, embracing challenges which include working with elevated temperatures, increasing in situ and mining induced stress levels and longer ore transport routes. Improvements in mineral processing technology will tend to lead operators to contemplate the extraction of lower grade orebodies in the event that the ore can be efficiently transported to the surface and hence the plant. No doubt this tendency, and its associated challenges is encouraging a rich growth in innovative engineering in such fields as mine planning and materials handling as well as geomechanical issues such as support design and the simulation of extraction sequence effects on stress re-distribution. MassMin 2000, we are sure, will showcase a wide variety of new contributions in thought and actions in these fields. There is a definite place for academic institutions and mining related suppliers in the process of developing new technologies and practices in support of present and future endeavour in this field. Dyno Nobel has its own part to play, certainly as an enthusiastic and proud major sponsor of MassMin 2000, but also by means of identifying common cause between our Vision and Values and the needs, present and future, of the underground massive mining industry. The critical success factors, which Dyno Nobel pursues are:health, safety and environment, customer relationships and market development, cost optimisation (while maintaining quality), technology and innovation, organisational development, and leveraging capabilities globally. Through the present paper we would like to share some of these values and offer some practical insights as to how their realisation will contribute to the achievement of MassMin goals and needs.

Jan 1, 2000

By T Leach, I Pringle

The Bowdens Silver Deposit is a low sulfidation epithermal silver-base metal deposit that has formed on the northern margin of a hydrothermal system within air-fall breccias, ignimbrites and crystal tuffs of rhyolitic composition. The deposit lies near the north-eastern margin of the Lachlan Fold Belt and the rhyolitic host rocks are of Early Permian age. The silver mineralisation occurs as flat-lying zones of disseminations and silicic fracture-filling within the Rylstone Volcanics and is closely associated with sulfides of iron, arsenic, lead and zinc. High-grade silver mineralisation is also found in steeply-dipping fracture zones which host banded sulfide veins. Studies of the alteration products indicate that high temperature fluids, flowing from south of the current project area, resulted in quartz (¦adularia) û illite/sericite alteration. Cool, low pH steam-heated waters on the northern and eastern margins of the prospect area resulted in siderite û smectite-illite clay û Fe-carbonate û marcasite û kaolinite alteration. Mixing of the two fluid types resulted in the deposition of iron and base metal sulfides, a decrease in both sulfur activity and pH of the mineralising fluid, and subsequent silver mineralisation.

Jan 1, 2004

Although the diesel engine is normally considered a tried and proven power source, many new and exciting diesel design concepts are being evaluated in engine development laboratories around the world. Three such programs currently underway at Cummins Engine Company are discussed. The turbocompound engine converts into power exhaust heat energy which is normally wasted. It does this by incorporating after the turbocharger a low pressure gas turbine which is gear driven to the crankshaft. The adiabatic engine has no conventional cooling system. It converts into useful power most of the heat energy normally rejected to the coolant. The series boost turbocharged engine uses seperate low and high pressure turbochargers to increase engine output and improve transient performance. These design concepts make possible increases in diesel engine thermal efficiency from the current 33 to 38 per cent range to the 50 percent range.

Jan 1, 1982

By G Diprose

Diamond exploration in Queensland is influenced by the South African approach modified by the discovery of diamonds in Lamproite in Western Australia. The current approach is to explore for Kimberlite and Lamproite bodies using indicator minerals dispersed by fluvial and colluvial processes. In the north-west, diamonds are derived from kimberlitic and lamproitic sources, whereas those in the coastal and subcoastal areas of eastern Queensland are associated with xenoliths included in rocks formed during Cainozoic volcanism. In these areas, sapphire is commonly associated with diamonds. In New South Wales diamonds in economic quantities occur in alkali basaltic intrusions and a subduction model has been proposed for these occurrences (Barrows et al, 1996). Exploration for diamonds in Australia increased following the discovery and exploitation of the Argyle mine. State geological surveys have produced digital information on the local occurrences of diamonds. As part of the Smart Mining Initiative (2006 - 2010), the Geological Survey of Queensland compiled a database and report on microdiamonds and diamond indicator minerals from open file company exploration data from 1968 to 2008 from the Department of Mines and EnergyÆs QDEX system. Most exploration in Queensland was conducted with exploration for other commodities. There is no commercial exploitation of diamonds in Queensland and, to date, only rare occurrences of microdiamonds. There is a regional difference in diamond occurrences with the kimberlitic and lamproitic models favoured for the north-western regions of the State and the subduction (S-type model) favoured for the eastern coastal zone linked to Cainozoic alkalic basaltic volcanism. Further diamond exploration is warranted in Cainozoic basalt provinces along the eastern coastal and near coastal regions and in the north-west of the state in conjunction with airborne geophysics flown as part of current Departmental Smart initiatives. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

For many years the mining industry at Broken Hill, New South Wales, Australia, was carried on with just sufficient attention to underground ventilation and hygiene conditions as to keep pace with necessity. However, the campaign against industrial diseases in other mining centres (notably South Africa) some years ago, brought the subject more prominently before local mining engineers.Throughout a period of several years, gradual improvement has been effected, and at the present time industrial hygiene is considered an essential part of the production operations of the various companies.In June, 1918, a move was first made by the Board of Trade advising an inquiry respecting the health of employees engaged in the metalliferous mining industry in the State of New South Wales. At the end of that year, a recommendation was made to the State Government by the Board of Trade that a Techni.cal Commission of Inquiry be appointed to examine and report upon the dust conditions of the metalliferous mines at Broken Hill. Following this a second report presented in 1919 made specific recommendations in respect to the scope of such a Commission. A Technical Commission of Inquiry was accordingly appointed and arrived in Broken Hill to inquire into the prevalence of miner's phthisis and pneumonoconiosis in the mines. Early in March, 1920, the examination of all mine employees commenced, and the work was completed in June, 1920. The full report of the activities of the Commission and the conclusions arrived at was officially published at a later date. Based on the recommendations...

Jan 1, 1940

Mining projects have long since presented challenges for the protection of the water environment. Lessons learnt from historical pollution incidents and increasingly stringent environmental controls have significantly improved the environmental performance of mines in developed countries. In contrast, water protection legislation and guidance in the Former Soviet Union (FSU) countries, based on the æpolluter paysÆ principle, has not promoted the prevention of water pollution, and examples of poor environmental performance in mining still exist. However, there is now evidence of emerging legislation encouraging the protection of the water environment. This paper provides an overview of water protection legislation in the Russian Federation and Armenia and highlights some of the challenges facing international mining companies developing projects. A mining case study is described, which highlights how communities in Armenia increasingly value their water environment. Here, greater public participation in development projects is playing a vital role in influencing water protection legislation. It is considered that public opinion and emerging legislation will increasingly present challenges for the development of mining projects.

Jan 1, 2006

Better quality at lower cost is today's formula for remaining competitive in a world market. For an integrated steel company, high quality low cost steel production must originate before the blast furnace. In 1979, when U.S. Steel initiated a Quality Management Program throughout its steelmaking operations, efforts began at the coal, ore and flux mines. The objective was to improve the quality and reduce the variability of the critical parameters for steelmaking raw materials, to get the blast furnaces, and subsequently the melt shops, under optimum control. The general details of U.S. Steel's Quality Management Program are discussed and how it was used to promote the desired improvements in steelmaking raw materials. Some of the outstanding results obtained by the cooperative efforts between the mines and the steel plants are reported. The lessons learned by U.S. Steel were through upgrading existing operations and facilities. These principles should now be applied to new projects and the benefits of good quality management should commence from the time new projects are Commissioned.

Jan 1, 1986

By W Boughton, L Gilbert

The Australian Water Balance Model (AWBM) has found widespread use in Australia in estimating the streamflow behaviour of catchments. It has been used at the Ridgeway Gold Mine, in central west New South Wales, to estimate streamflows in creeks potentially affected by loss of spring-fed baseflow due to mine dewatering. The AWBM estimates are used to assess the effect of mining on streamflows and the need to provide compensatory flow releases, which would be drawn from mine water supplies, into the creeks, in compliance with regulatory consent requirements. The monitored flows in some of the creeks exhibit non-typical behaviour, with streamflows increasing in autumn months despite a lack of significant rainfall. This behaviour is believed to be due to the combined effects of discharge from rock fractures and the effects of evapotranspiration in the riparian zone. A modified version of the AWBM has been developed which much more closely simulates the observed flow behaviour and which will be used in ongoing flow assessments for the mine. This paper outlines the difficulties involved in modelling low flows in small catchments that are subject to a number of influences (other than mining), describes the development of a refined model to improve simulation of low flows and baseflow in small headwater catchments and highlights the need for good baseline data to calibrate such models.

Jan 1, 2006

THE treatment by chlorination of the Mount Morgan Gold Mining Company's ores was first accomplished, early in 1886, by a works having a capacity of 25,000 tons per annum. Shortly afterwards another works was established, capable of dealing with 50,000 tons per annum. The extraction of gold was originally successful and satisfactory, but running expenses were high, averaging £2 19s. 6d. per ton of ore treated. These works were believed to be the largest chlorination plants in the world at that time. As might have been expected, the mechanical details and chemical process had not been perfected, and, moreover, both works were hurriedly built, and operating expenses were not then considered of such prime importance, as the ore at that time was of very high grade; the large quantities of low grade ore since dealt with not being then considered, since the bulk of it was not even known to be in existence. These two works consisted of rock-breakers, high speed rolls, screens, elevators, &c., for crushing; a large number of small handrabbled reverberatory furnaces for roasting; one-ton chlorination barrels and three-ton leaching vats for chlorination. The transport of ore from crusher to furnaces, from furnaces to chlorination barrels, and the emptying of leaching vats was effected entirely by hand labour. The system of chlorination was what was, known as Mears process, chloride of lime and sulphuric acid being used in the chlorination barrels, and as the time allowed...

Jan 1, 1911

By R Pie, J Crusius, P Whittle, J J. McNee

The Main Zone and Waterline pit lakes at the Equity Silver Mine near Houston, BC (Canada) are the sites of an ongoing three-year government- and industry-funded research program. In order to assess the feasibility of various bio-remediation strategies, field-scale manipulations were conducted using enclosed mesocosms (limnocorrals). Two manipulation strategies were tested: addition of algal nutrients (phosphate and nitrate) to Main Zone Pit surface waters; and addition of algal nutrients (surface waters) and dissolved organic carbon (deep waters) to the Waterline Pit. Nutrient addition was conducted in order to stimulate algal production and enhance metal scavenging by biogenic particles, while dissolved organic carbon (ethanol) was added to increase oxygen demand and foster the development of sulfate reduction in pit bottom waters. Fertilisation resulted in rapid growth of natural phytoplankton populations in the surface waters of both pits. In the Main Zone Pit, the stimulation of algal growth resulted in the pronounced removal of both dissolved and total metals (Zn and Cu) from surface waters, with higher rates of metal removal being observed at higher nutrient additions. Metal removal could be attributed to the scavenging of dissolved metals by biogenic particles and subsequent particle settling. A similar pattern of removal from surface waters was observed in Waterline Pit (Zn and Cd). The addition of ethanol to deep waters in Waterline Pit was effective in promoting sulfate reduction in the lower layer. The development of reducing conditions resulted in near-quantitative removal of dissolved Zn and Cd, presumably as secondary metal sulfides. Iron, As and Ni profiles in Waterline Pit exhibited no evidence of removal from either surface waters or bottom waters. Collectively, the results demonstrate that the passive forms of bioremediation tested in these pit lakes may be effective for whole pit-lake remediation.

Jan 1, 2003

By Rivers CJ

The Brolga deposit is a Ni-Co enriched laterite, formed over intensly serpentinised peridotites of the Marlborough Block. Basement lithologies at Brolga consist predominantly of serpentinised dunite, with lesser massive serpentinite shear, gabbro and harzburgite. Investigation of the deposit has defined 17 different varieties of saprolite, ferralite (limonite), and ferricrete. Different combinations of these varieties form three distinct lateritic associations, the Hard, Soft and Dyke Associations. Recognition of key textural and mineralogical features in each association, an understanding of basement geology, and an awareness of current climatic conditions, suggest that: 1. both the Hard and Soft Associations have formed under relatively dry climatic conditions; 2. the Soft Association reflects much poorer groundwater drainage than the Hard Association; and 3. the Dyke Association has formed from a gabbroic basement, and has also been affected by restricted groundwater drainage, caused by poorly permeable marginal serpentinite shears.

Jan 1, 1996

Evaluation of reserves on a production scale within a shear-hosted gold deposit is complicated by the nature of the mineralisation itself. The 'payable' ground seems to be confined to areas with intense shearing, while the remainder of the deposit is characterised by 'background' mineralisation at a very low level.

Jan 1, 1993

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

By Roxborough F. F

The ability of the Australian minerals industry to successfully manage the changes and challenges that face it in the 21st century depends ultimately on the quality of its human resources. Mining engineers have a vital role in this regard. The education and training that universities are currently giving to mining engineers is under challenge and needs to be reassessed in the light of industry directions for the 21st century. At one extreme is a push for a `finished product' graduate, up and running in `the flavour of the month' issues. At the other extreme are moves to reduce face-to-face university teaching hours and return to the time honoured university concept of `reading' for a degree. The lessons of Mourn make it apparent that neither approach is appropriate to the industry's future needs (Windridge, 1996). Basic knowledge gets rusty with time and new skills need to be learned. In order to conduct mining operations safely, productively and competitively, mining engineers must now accept the need to be prepared for continuing professional development as a career imperative. The concept of being professionally or statutorily qualified for life is no longer valid. This calls into question the purpose, content, structure and mode of delivery of university courses, all of which need to engender the principle and facilitate the cause of continuing professional development. This paper presents a model which aims to deliver a quality assured university education for mining engineers for the 21st century at undergraduate, postgraduate and professional level. The model extends beyond traditional university boundaries to match industry requirements to international best practice. It is based on collaborative alliances and innovative presentation modes which will provide industry access to undergraduate and postgraduate course elements presented by a broad range of national and international academic and industry authorities. It offers the prospect for preserving the best of university ideals in higher education, for developing and maintaining programs of direct relevance to industry needs and for a structured involvement in the continuing professional development of mining engineers.

Jan 1, 1997

Interest in the sampling of refined copper cathodes has heightened over the last ten years. This has followed the increasing importance of cathodes as the principle trading form for metallic copper. It has also been given impetus by recent trends for quality certification of manufacturing inputs, specifically the AS3900 and IS09000 series of standards.

Jan 1, 1976

The methods employed in dressing 'the tin ore up to the required percentage of purity depend mainly on the type of ore crushed.These may be briefly divided into two distinct classes-viz., q, free: milling ore and a complex milling ore. In the former the ore is practically free from the common metallic sulphides, such as pyrites, mispickel, blende, galena, etc., and 1!' clean concentrate of 70 per cent metallic tin can be directly obtained in one continuous act of concentration; in the latter, however, in order to get a good extraction, it is only advisable to primarily concentrate up to 30 to 40 per cent. tin oxide, the rest being the sulphides of the metals. This concentrate is then roasted, re-ground, and re-concentrated up to 70 per cent. metallic tin on a separate set of tables.In the complex milling ore the tin is intermixed very closely with the sulphides, so that it becomes necessary to collect all the mineral present in order to obtain clean tailings. Stamp mills are the most popular machines for the primary crushing in the district, but whether they are invariably the best for the purpose is rather an open question. No doubt for some of the very tough chloritic ores they are the most efficient, but for a brittle quartzose ore, such as the free milling proposition usually is, the writer thinks Oornish rolls would well hold their own, especially when the tin occurs coarse, as is so often the case with this class of ore. Of course, the great drawback to stamps is the excessive quantity of tin slimed and slime tin is one of the problems of tin-dressing-while rolls give...

Jan 1, 1907

It is my pleasure to deliver the first Keynote Address to the first joint conference between The Australasian Institute of Mining and- Metallurgy and The American Institute of Mining, Metallur- gical and Petroleum Engineers. I am particularly pleased to be participating in this first joint meet- ing as I have been a member of one Institute for 41 years and the other for 35 years. An examination of the membership of both Institutes confirms the fact that the mineral in- dustry is an international one. This has long been the case and basically stems from the occurrence of mineral resources in most countries of the world. It is therefore fitting that these two 'Inter- national Institutes', representing the professions involved in the mineral industry, should choose `International Resource Management' as the theme of the first joint conference. The topic of this Keynote Address is `The mineral equation' or the counterbalancing supply and demand items and the factors affecting them. I propose to attempt to present the overall picture of the mineral equation as subsequent papers and sessions will deal with specific items in more detail. My thesis is broad and deceptively simple; it is that the continued existence and growth of world material civilization depends, in large measure, on the continued use and further dis- covery of world mineral resources. Material civili- zation is used as a broad term to include the pro- duction of man's shelter and tools together with the production of the `consumer' goods and ser- vices needed by society. First let us spend a few minutes looking at the development of material civilization.

Jan 1, 1978

The unique chemical and physical properties that can be displayed by polypropylene and its copolymer derivatives are enabling its development as a truly versatile material for water filtration. Well known applications include spiral wound cartridge filters commonly used for household water or the office drinking fountain, to pressure membranes that provide micro, ultra or nano size filtration barriers, whilst needle-felt or woven cloth filter belts or inline pressure bag cloths are well known to the hydro metallurgist and process engineer. A relatively new filtration concept that is generating interest and applications across all industries including the mining sector involves use of a unique fabric type filtering media made from polypropylene fibres. This technology not only has a vastly wider window for potential applications, it delivers an attractive cost saving alternative to the traditional sand media or diatomaceous earth type filters, along with potential benefits for integrated filtration units. This paper discusses the proven potential of the fabric media technology with examples of performance comparisons and confidence gained from full scale operating installations at mine sites and other locations.

Jan 1, 2004

By L Soares, W T. Hennies, F Fujimura

The engineering geological mapping of Metropolitan Area of Jopo Pessoa in the littoral zone of the Parafba State, northeast of Brazil, made possible the ambient characterisation for space using and its implications on the environmental resources. This region comes lately denoting an accented industrial growth and this work would help future projects of urban planning, distinguished by quick ground occupations for residential, industrial installations, farming, beyond mineral extractions. The mineral sector supplies material and substance demanded by industry and civil constructions, like as clay deposits, sands, calcareous rocks and mineral water. Many companies working there do not have the permission or inspection of ambient agencies for planned extractions of mineral resources. The consequences of this activity pass for the low profit of the reserves, bad uses of the sources, ground degradation, vegetation suppressions and physical impacts on landscapes, beyond noises and vibrations. These activities have causing accelerated alterations and transformations in the environment, compromising the sustainable development. It thus becomes clear that urgent solutions must be find to solve the problems with human interferences by closer inspection and management for disciplined use of its natural resources.

Jan 1, 2003