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The potential of the developed multi-dimensional analysis system to assist interpretation from large data sets through derived digital mapping models is presented accompanied by preliminary results. The concept learning model is original and its application general. Applications exist in general science, engineering, earth resource management and economics. The developed system incorporates advances in machine learning, neural networks, object-oriented software engineering, knowledge representation and fuzzy logic. ' The specific application presented involves automatic earth resource modelling and assessment involving geological theories of mineral potential. The developed system functions as a new and powerful mineral exploration tool, To date the model has been trialled on an earth resource database and several published data sets. A more general potential application is knowledge discovery within databases. The specific theory that is tested in the experimental results is the nature of the cause-effect relationship between the hypothesised geological causes and the measured effects within a previously published test survey. Also integrated here are a neurophysiological cerebellar model of human learning, a new concept similarity measure for pattern recognition, modelled components to explain human concept formation through knowledge discovery and a means of permanent representation.The implementation is as a new artificial neural network architecture functioning as a hybrid expert system. Understanding of programmed concept learning is extended through the model. Also established is a basis for a new approach to multivariate data analysis. Spatial analysis for decision support is integrated over many dimensions, relationships, data types and data modes. Application of the developed methodology and system adds value to data bases. Discovered knowledge is represented as new generalisations, interpolations, classification hierarchies, aggregations and associations within a dynamic, maintainable and reusable integrated knowledge framework. New digital knowledge products and intelligent access follow. Permanently stored, maintainable, easily accessible and discovered knowledge improves decisions through extended hypothesis testing, spatial data analysis and inferencing, prediction, logical deductions and explanations.

Jan 1, 1995

A nuclear technique utilising the gamma-ray resonance scattering process is used at Isa Mine for the determination of copper in drill core and bulk mineral samples. The Copper Bulk Analyser (CBA) provides quick and accurate non-destructive copper analysis of drill core at costs two to three times cheaper than conventional chemical techniques.The almost immediate availability of sample results enhances the efficiency of the mine geologist in the duties of grade control, design of diamond drilling programmes, and input to planning. The unit has proven to be a reliable and accurate production tool requiring a minimum of technical support.

Jan 1, 1990

By Harraway DH, Tanner AC

The various circuits tried!at Mount.Isa Mines during the period 1959-1963 to improve the differential%f lotation of galena and sphalerite are reported. The benefits and disadvantages of 'the various circuits are discussed. An analysis of ore charao-beris;ics.and their effect on flotation is followed by the d~soription,of a proposed".cirouit in the process of install-ation.

Jan 1, 1963

By Skinner J, Brackenbury K

The AuPlus" Systems have been applied in the gold mining industry to achieve improved gold recoveries, faster leach kinetics and reduced cyanide consumptions. Calcium or hydrogen peroxide, collectively known as peroxygens, can be used. The choice depending on plant design and the nature of the ore. Laboratory test work and plant trials are included in this paper to illustrate the benefits of peroxygen usage in extractive gold metal- lurgy.

Jan 1, 1991

Host minerals for gold have been of great interest to exploration geologists and metallurgists for a variety of reasons. The depletion of high grade ores in many parts of the world requires that greater attention be given to the study of host min-erals for gold. Some host minerals have been employed in exploration as traces for gold. They are also essential in the design of extraction processes for treating gold ores.This paper reviews the mineralogy of important gold deposits of Papua New Guinea (PNG), Indonesia and New Zealand and focuses attention on the ore minerals and rock-forming minerals that host gold.

Jan 1, 1994

The 250 metric tonnes of gold and 360 000 metric tonnes of copper recovered from the Mt Morgan Mine in Central Queensland justify its fame. The mine ceased operation before the advent of three-dimensional computer graphical modelling of orebodies became common practice in mine planning. The Mount Morgan Mine records however remain and are the database for this study. The Mount Morgan project takes ore deposit modelling one step further by examining the relationship between grade distribution within the orebody and key geological features, as a tool for exploration and development.The Mount Morgan gold and copper mineralisation is shown to be strongly lognormally distributed. The deposit has been split into three areas, using geological boundaries, each with different geostatistical characteristics. Important features include: the spatial relationship of near-vertical, high grade shoots with a ring dyke thought to be related to the North Dyke; separation of the high grade eastern stopes from the others along the Andesite Dyke; and lack of concentrated mineralisation along the Slide Fault.Recognition of these features is useful to those currently exploring the Mount Morgan district for similar style deposits, by stressing the importance, or lack thereof, of the geological features.

Jan 1, 1993

By Cuff C, Taylor RG, Georgees C

Mineralisation adjacent to Herberton occurs within three main subcentres. The Her- berton Hill subcentre is characterised by the association of Sn,W the Herberton Dividing Range South subcentre by Sn, and the Herberton Dividing Range North by Cu, As. The relation- ships between the subcentres are discussed in terms of metal distribution, production, deposit types, wall rock alteration and re- lationships with granitoid intrusives. The temporal and three dimensional spatial re- lationships between the centres are uncertain.

Jan 1, 1978

By Fourney W. L, Dick R. D

Tests were conducted in plexiglass and Rockite models to determine if crater blasting could be improved by changes in charge geometry or by alterations to the borehole. Circumferential grooves were placed at various locations in the borehole in an attempt to control the initiation site of the crater. Grooves located at or above the top of the cylindrical charge had no effect on the resulting crater. Grooves placed too low in the borehole were successful in controlling the initiation site but the growth of the fracture system was not sufficient to reach the upper surface. Grooves located at a height of two thirds of the charge length were quite successful in that resulting craters were bigger by at least a factor of six than the normal crater. Testing was conducted in Rockite models to investigate charge geometry. Spherical charges in ungrooved boreholes resulted in crater sizes that were three times larger than those caused by cylindrical charges.

Jan 1, 1990

By M-E Boucher

While the haematite concentrates produced in Eastern Canada and the magnetite concentrates that Australia will soon be producing are different feed materials, the pellets they produce have similar physical and metallurgical properties. This paper will examine the similarities and differences in the evolution of pellet microstructure for pellets produced from magnetite and haematite. The molten slag phase generated at high temperatures has a lower melting point when in contact with magnetite compared with haematite due to the higher divalent iron content. The presence of some slag is beneficial for bonding but too much can inhibit oxidation of magnetite, although slag generation at lower temperatures reduces energy usage. In pellets produced from haematite, magnetite is generated artificially from the combustion of the carbon particles added to the pellet feed as a source of energy. Maintaining the optimum production level and mineralogy of such æsecondaryÆ magnetite, allowing for its subsequent reoxidation, is important for the quality of haematite pellets. In both magnetite and haematite pellets, balancing the slag formation and oxidation (re-oxidation for haematite pellets) of the magnetite (secondary magnetite for haematite pellets) is necessary.

Jan 1, 2007

By Bangerter PJ

The use of gravity concentration is, and has always been, the conventional primary method for gold recovery from alluvial deposits. The development of high capacity cone concentrators and metallurgically efficient wash-waterless spiral separators has had some impact in the technology for alluvial gold processing, but perhaps more significantly has led to the relatively recent use of this gravity concentration technology in grinding circuits of hard rock ore for "coarse" gold removal and for scavenging gold locked in sulphides from cyanidation tailings streams.Gravity concentration systems are relatively low-cost, non-polluting and energy efficient; and their judicial use in gold treatment plants can significantly reduce overall capital and operating costs.The application of modern gravity concentration technology to hard-rock and alluvial gold ore treatment is discussed. Flowsheets and test and operating data from a number of gold processing operations incorporating gravity concentration treatment are presented.

Jan 1, 1984

By Glastonbury J. R

Commercial operation of the Sherritt Gordon process in Australia for the leaching of nickel sulphides has promoted an investi- gation of the factors which influence extraction kinetics. This portion of the investigation has been directed towards the physical and chemical nature of the concentrate and the physical evi- dence of the mode of extraction. Details of the particle size distribution, mineral composition and chemical composition are given. The dis- tribution of various minerals in different size fractions and magnetic fractions is discussed. An electron microprobe was used to determine the composition of individual grains in the concentrate. The solid residue from an ammonia oxi- dation leach was subjected to microphotograph- ic examination, X-ray diffraction analysis and scanning by an electron microprobe. Clear evidence was obtained for a shrinking core mode of kinetic extraction with an amorphous iron oxide product layer contrary to previous reports that the latter is pseudomorphic with the original mineral.

Jan 1, 1973

Small mines exist because of a restricted deposit or a small market. With the right management at the present time the small mine can have lower total costs than larger mines. Charbon is an example of a small mine with a restricted deposit and a specialised product. The development which incorporates a unique rail loading facility and flexible coal preparation plant was achieved with a modest capital outlay and in record time. To remain competitive in future with large scale mines who seek increased production the small mine must achieve increased productivity through automation, higher speed equipment and a multiskilled workforce. Deregulation of the industry, scrapping the Coal Industry Tribunal and the Joint Coal Board would benefit small mines greatly. Management of a small operation also requires multiskills which need to be supported by outside help in the form of consultants and temporary staff. In the 21st century small mines will continue to provide a service to the market.

Jan 1, 1988

By J J. Cilliers, K Hadler, A W. Stra

This paper examines the use of the FrothSim flotation simulator to improve the performance of an industrial column flotation cell. The performance of an industrial retreat column cell is simulated, and, from the discrepancies between the simulated and experimental results, a problem with the wash water distribution is postulated. The scientific reason for the reduced performance with uneven wash water addition is described in detail. Further simulations indicated the potential for improvement with an even wash water distribution, resulting in both improved performance and reduced wash water usage. The simulated uneven wash water distribution was confirmed industrially, and the headers were redesigned and installed. A sampling campaign to compare the performance before and after the modifications showed that the flotation performance was improved dramatically, with a statistically significant decrease in gangue recovery, without a commensurate reduction in valuable mineral recovery.

Jan 1, 2005

Any project carries a number of challenges and risks. Inappropriate design, poor project management, time, industrial disputation and capital over runs are all areas which can impact on a project cash flows and return on investment. In the resource Industry you have the added complexity and risk of geology which is difficult to predict and sometimes unforgiving. The Dartbrook Mine was designed and constructed as a high output longwall mine and has overcome a number of hurdles to produce over 2.3 million tonnes for the first year of operation. A number of problems were encountered during construction which resulted in the inseam development being delayed for six months. Dartbrook people have demonstrated they can manage adversity and produce world class results. The mine has been through a very steep learning curve during 1997 and with this experience behind the mine is now producing at an annualised rate of 3.4 MTPA.

Jan 1, 1998

By Andrews JRG

Chrysotile asbestos is a valuable resource. Used as a reinforcement in asbestos cement, products are obtained which are cheap, are not attacked by vermin, do not rot or support growth of fungi and are unaffected by water or humid conditions. Such products are of great value in the developing countries where inexpensive and durable building materials and pressure pipe are very important to development, housing and water supplies. Concern over the adverse effects of inhaling asbestos has led to the introduction of increasingly stringent controls world wide on the quantities of airborne asbestos per- missible in the occupational situation. Wet processing has the potential for virtually eliminating the environmental concerns with asbestos dust both in fibre production and in the materials handling section of the manufac- ture of asbestos cement products. In addition, high efficiencies associated with wet process- ing mean that better yields are obtained and that the tailings which are dumped have a lower residual asbestos content. Since early 1977, ICI Australia and Woodsreef Mines have been engaged in a programme of research to develop and evaluate a wet mill- ingprocess to produce, from ore and existing tailings, high grade fibre suitable for use in asbestos cement products. The process has been developed through microscopic studies, labora- tory bench scale experiments, work in a small scale semi-continuous plant and product evalua- tion on experimental size Hatschek asbestos cement machines. A prototype mill with a normal feed rate of 1z tonnes per hour and capable of producing pipe grade asbestos from Woodsreef ore has been constructed and was operational from January, 1982 to July, 1983. A range of asbestos cement products have been made successfully on full scale Hatschek machines using fibre from ore and tailings milled in the prototype mill. Economic evaluations indicate that a wet process mill would be cheaper to build, operate and maintain than an equivalent dry process plant. A commercial plant has been designed 1. Manager New Process Development, Woodsreef Mines Limited, Barraba, Australia. 2. Senior Lecturer, Department of Chemical Engineering, Monash University, Vic, Australia. formerly Senior Research Officer, Research Department, ICI Australia Limited

Jan 1, 1986

By K E. Barns, P J. Sharman, S A. Thomas and

This paper presents the development of a regrind facility design at BHP BillitonÆs Leinster Nickel Operations (LNO) in Western Australia. The recovery opportunity was identified from an analysis of plant operating data together with scanning electron microscope (SEM) measurements on relevant tailings streams from LNO. A laboratory procedure was developed to determine the potential recovery improvement of installing a regrind facility at LNO. The last step in formulating the process flow sheet and defining the process design criteria was to construct and operate a pilot plant, which incorporated four banks of flotation cells and an Xstrata M20 Isa Mill. Pilot plant on/off trials were used to define the expected metallurgical benefit. A prefeasibility engineering design and cost estimate was completed. Following a successful internal business evaluation, a feasibility study is currently underway.

Jan 1, 2007

By Joussemet R, Fabre F

The paragenesis of the Escuzar Mine (Andalusia-Spain) comprises: ò major constituents: celestite and carbonated minerals (abundant calcite and less frequent strontianite). ò minor constituents: sulphates (gypsum and anhydrite), clays and some iron oxides and hydroxides. The average content is at about 60 per cent SrSO4. Since liberation size was fine (from 30 to 50 ¦m), the flotation method was chosen. Laboratory batch tests have shown the relevance of using alkylsulphates with as long as possible hydrocarbon chains. The recovery obtained led to an expected 95 per cent SrSO4 concentrate with nearly 70 per cent recovery. Pilot plant tests (160 kg/h) have confirmed these results and attained a recovery of more than 65 per cent of a 96 per cent SrSO4 concentrate. Extrapolation to the industrial scale (14 t/h) has been successfully carried out : up to 600 t of a concentrate at more than 95 per cent SrSO4 has been obtained. Non optimised recovery has already reached 60 per cent for a 97 per cent SrSo4 concentrate.

Jan 1, 1993

In discussing the Asia-Pacific region weare talking about a region which has more than 60% of the world's population, a regional economy which will in 10 years be larger than the European Economic Community, and a group of countries with some of the highest electricity generation growth rates in the world. It is economically the most dynamic region in the world.

Jan 1, 1990

The Koongarra uranium deposit was discovered in August 1970 by Noranda Australia Limited. Denison Mines Limited acquired the rights of ownership in October 1980 and has continued the 'struggle' to bring the proposed mine, containing approximately 13 300 tonnes of U308 of Indicated ore and having a value of $1 billion (1984 dollars), into operation. During the 14 years that have passed, the owners have found it necessary to deal with numerous Federal, State and Territory government departments, aboriginal representatives, handle thousands of communications, attend and convene countless meetings and spend millions of dollars. This paper addresses the history, the requirements, the problems and the costs to date for what - no return.

Jan 1, 1984

By Kupper T

Firstly, electric analog models are discus- sed to show fluid streaming conditions. In these models the depth of blast at tuyere level, the height of the bath, the influ- ence of different angles of the furnace zones and the different possibilities of the root of the cohesive zone have been changed. Tests to define the influence at a large blast furnace are given. Secondly, the wear of carbon bricks in the hearth is examined under the influence of gas, slag and pig iron. Oxidation tests in a special scanning microscope with the pos- sibility of heating and gas treatment are shown. Wear mechanisms are discussed fora large blast furnace and proposals for im- provement are given. Finally, the possib- ilities and value of the temperature meas- urement in the hearth block are discussed.

Jan 1, 1981