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By Rashkovski GB

Until recently amalgamation has been the main process forextracting large gold particles from gravity concentrates obtainedduring the dressing of ores and placer gold deposits.Development of new technology for treating the gravityconcentrates was necessary because of the harmful effect ofmercury on subsequent production processes and theenvironment. The harmful effect of mercury is particularlyevident in the resin-in-pulp process that is widely applied inRussia.

Jan 1, 1993

In both surface and underground coal mines, the detection of geological structures ahead of workings is recognised as being fundamental to the efficient operation of the mine. Mining into zones of unexpected structures has a drastic effect on a mine's productivity. For the prediction of structures, geophysical methods can be applied from the air, from the ground surface, from boreholes and from underground workings. There are several improvements to report in the geophysical methods being developed for these purposes. These include developments in three-dimensional seismic reflection surveying, cross-hole seismic reflection methods and radar systems. The recent development of the radio imaging method for use in underground mine workings will complement existing in-seam seismic methods. Geophysical techniques for use in horizontal boreholes are also under development.

Jan 1, 1988

The optimization of management structure systems for coal mines is undertaken with the use of economic and mathematical models of the monitoring, manufacturing, and functional subdivisions of the systems. The main para- meter to be minimized is economic loss result ing from organization faults and this is achieved, in part, by optimum distribution of both technological objects and engineering and technical personnel. Models used are of the "gated" type, parameters for which are derived from analysis of manufacturing processes and from automatic information systems. The use of these models ofmanagement structures is only part of the process of optimization of those structures for coal mining operations.

Jan 1, 1977

The three main types of iron ore deposits in Australia are bedded, massive and residual. Some character- istics of iron ore, important in its process behaviour, are related to its mineralogy which is a result of its geological history. World iron ore resources are extremely large but there are problems in quantifying re- serves, defined as that part of re- sources from which a useable commodity can be extracted economically. The relationship between the discovery and exploitation of iron ore resources and the process of industrialization is examined in historical and present day contexts.

Jan 1, 1976

The role and policies of the Aboriginal Sacred Sites Protection Authority are described in conjunction with the provisions of the N.T Aboriginal Sacred Sites Act 1978. Comment is made on the application of the legislation and these policies to development proposals in the Northern Territory. A brief review of criticisms by both developers and Land Councils is provided together with responses to these Criticisms.

Jan 1, 1984

Cordeaux Colliery is more logically sited than the historic escarpment Corrimal Colliery, on the same reserve. At Cordeaux the modernisation of mine plans and equipment and the introduction of high production longwalls have created a record achieving producer of both steelmaking and export coals.Further changes achieved have been in employee related attitudes and performance, enhanced by business strategies and total quality control and particularly benefiting from innovative employee input With this present example of co-operative effort Cordeaux Colliery will continue to improve through management of total quality. resources, development rates and customer satisfaction.

Jan 1, 1991

Peraluminous metamorphic rocks may form from a variety of protoliths by a range of processes. Stratiform bodies of such rocks are relatively common in the Precambrian, but less commonly, also occur in the Phanerozoic. The protoliths of such stratiform bodies may have been regionally deposited chamosite-rich sediments, with varying amounts of clastic component, or may have resulted from the in-situ depositional or diagenetic alteration of volcaniclastic sediments, ranging in composition from rhyolite to basaltic andesite.Stratiform peraluminous metasediments, especially those of low to medium metamorphic grade, and relatively iron rich, may be genetically associated with, or be the host rocks for, a variety of styles of mineralization, especially for the ores of An, Ag, Cu, Zn and Pb.

Jan 1, 1990

The long term viability of a mining company is dependent on the success of its capital investments. Due to the specialised nature of the design, engineering and construction of large projects the management is often contracted to an outside organisation. This paper is a review of the phases of the relationship between Client and Contractor. A rationale is developed upon which the selection of a Contractor can be made. Subsequently, the key aspects of the Client/Contractor relationship are reviewed with reference to completing the project on time within budget. The aspects discussed include Contractor management systems, qualifications of key personnel, definition of scope of work, industrial relations, project control and Contractor remuneration.

Jan 1, 1983

This paper considers the opportunities and problems which in-situ leach mining technology presents to the mining industry. These are exemplified by concerns addressed in the development of a proposal to mine uranium by in-situ leach techniques at Beverley in South Australia.

Jan 1, 1988

The difficulty of successfully imple menting a landscape policy is almost incom- prehensible. Landscape design is recognised as an essential component in the integration of engineering and architectural projects into the landscape, but the factors which prevent the achievement of a successful result are rarely recognised or assessed. In many cases these prohibiting factors are due to a lack of understanding of the effect of major planning decisions on the existing landscape, the importance of the landscape plan and the significance of appro- priate specified techniques to prevent un- necessary damage and to ensure retention of existing vegetation in a healthy condition. The role of the landscape architect in incorporating new land uses into the landscape provides the background against which factors which inhibit policy achievement can be con- sidered.

Jan 1, 1976

By Seshold P

The cost of capital is the rate at which a project's cash flow should be discounted to obtain the Net Present Value. The cost of capital is a weighted average of both debt and equity funds of a company, on an after tax basis. Two methods are described for calculating a company's cost of equity, the Dividend Valu- ation Model and, more importantly, the Capital Asset Pricing Model. A worked example is presented where the cost of capital was obtain- ed for two resource companies. The application of the cost of capital was illustrated by way of a mining equipment replacement problem. The paper outlines refinements and problems that may be encountered with the use of the cost of capital, and concludes that it is an integral part of any project evaluation.

Jan 1, 1983

By Connor J. W

Nifty Copper Operations was established to treat a copper orebody situated in the East Pilbara area of North West WA, located approximately 70 km west of Telfer in the Great Sandy Desert. The plant was designed to treat the oxidised portion of the orebody with underground development following at a later date. Nifty was designed to produce 16 500 tpa of copper cathode. This will increase with treatment of the chalcopyrite ore (underground resource). Ore processing is similar to other operations of this type but has its unique challenges. Problems discussed are: fine clay minerals which hinder percolation; oxidation of organic by manganese in the electrolyte; crud formation by clays; third phase emulsions; and organic carryover into the electrowinning tankhouse. As the orebody utilisation progresses, some sulphide material will require leaching and further investigations into liquor chemistry.

Jan 1, 1996

Clearly visible in geophysics is a trend away from simply finding and drilling anomalies obtained with off-the-shelf equipment, condes- cendingly sold by travelling salesmen. Instead, technical tools are becoming available which allow us to choose or design equipment and sur- vey procedures for the specific problem at hand. The advent of micro- and smaller computers enable us to collect more and better measure- ments and to rapidly process them so as to emphasize the features which are being sought. These new capabilities have important consequ- ences both to the extent to which geophysical tools will be applied in the industry, and to the skills which will be demanded of those using them. Because of its uniquely difficult exploration problems, Australia must expect to amplify its new prominence in the development of mining geophysical technology.

Jan 1, 1981

The present practices in electro-refining of copper are shown to be the result of piecemeal and gradual improvements and innovations as metallurgists responded to changing cost pressures and the availability of new technology.Major changes were inhibited by capital cost restraints and a reluctance to build unproven ideas into new plants.It is suggested that the level of technology available today, combined with the greatest cost pressures the industry has known, call for fundamental re-appraisal and a questioning of widely accepted conventional practices.Examples of the industry reaction to changing pressures are given, and directions for future developments are suggested.

Jan 1, 1985

In the past five years, there has been an evolution in the assessment and control of mining risks in the New South Wales coal mining industry. This change has involved the development and use of structured, systematic, team-based risk assessment exercises to identify, assess and control unacceptable risks to people, equipment and production. The outcomes have improved the management systems in the mine. This paper discusses the evolution of the risk assessment approach in equipment design and mine operations, as well as the specific risk assessment methodology. The paper also presents the reactive side of risk management, the method of investigating failures in the management system, usually referred to as incidents or accidents.

Jan 1, 1994

A continuous casting machine, of the Concast curved mould design casting billets in four strands, was commissioned at the Newcastle Works of The Broken Hill Proprietary Co. Ltd., in November, 1967. Quality assessment of early casts from this plant indicated that steel cleanliness was sometimes inferior to that of equival- ent ingot cast steel. Extensive trials to develop a modified deoxidation technique were not successful in improving clean- liness to the desired level. A "contra-flow" gas shroud, to cover the steel stream between the tundish and the mould, was developed, and proved successful in achieving the required levels of product cleanliness. The inclusion content of six grades of steel ranging in carbon content from 0.10 to 0.70 per cent is examined, and an attempt is made to explain theoretically some of the results obtained.

Jan 1, 1972

Gold mining commenced at Telfer in Western Australia in 1977. Ore mining was carried out by owner equipment and personnel with waste stripping by a contractor. Initial ore reserves were in predominantly high grade, geologically simple reef structures. A mining method was developed using dozers to selectively mine the ore bearing horizons with a minimum of dilution. As the mine has developed the simple, high grade ore reserves have been progressively replaced by more geologically complex, lower grade reserves. In turn, mining methods have evolved to extract this ore by the most appropriate methods. On-going attention to ore mining practices will ensure that project profitability and viable mine life are optimised.

Jan 1, 1986

Green policies have gained momentum since the 1972 Stockholm Environment Conference. The environmental movement has influenced political initiatives both in New Zealand and abroad. Governments and international institutions have addressed local, regional and global environmental issues with varying degrees of success. New Zealand so far has not supported the United Nations' call for sustainable development in a,consistent manner.New institutions and new rules for resource management mean there are opportunities to look after the land in different and more ecologically sensitive ways than has happened in the past.The increasing influence of regional councils in resource management planning will have important implications for mining and mineral exploration. These trends are discussed and possible future events outlined.

Jan 1, 1990

An outline of the circumstances giving rise to the current Commonwealth-States con- flict in relation to offshore mineral explor- ation and production is set out, together with an analysis of the Seas and Submerged Lands Act 1973. The bases of the claims by the Commonwealth and the States in this regard are discussed with relation to the territorial sea and the continental shelf.

Jan 1, 1974

By Meakins R. L, Talaska A, Kenny D, Haycraft J. A, Dickson B. L

A vehicle-mounted radiation detector interfaced to a microprocessor called PRAM (programmable radioactive analyser mobile) has been developed to provide grade control for selective mining of a soft rock uranium ore. The grade of ore over which the vehicle passes is determined and indicated by several coloured lights to a pegman who walks behind the vehicle. Coloured pegs are then laid out to mark the uranium grade ranges on the floor of the mine pit. Comparison between grade ranges determined by the PRAM and by prior drilling and downhole logging at the Yeelirrie deposit, Western Australia indicate good agreement. Use of the PRAM decreases the cost, manpower and time required to grade extensive areas of a mine pit floor.

Jan 1, 1982