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By Allchurch P. D

At Perseverance a reserve of 45 million tonnes at 2% Ni was indicated by drilling. Holes were drilled in trellis pattern on section lines 61m apart to assess shallow mineralization. To explore at depth holes were spaced 122m apart, collared vertically, then allowed to deflect under controlled drilling conditions. The mineralization may be divided into the three homogeneous classes of soarsely disseminated, heavily dissem- inated and massive sulphides. In the standardised sampling and assaying procedures used to assess the deposit, attention was always paid to these fundamental ore types. All sampling and assaying processes were continuously monitored by checks. Sampling and sample preparation errors were small, to judge from the differences between results of original and check samples. Assaying errors, determined from analyses made by independent laboratories using different methods, slightly exceeded sampling errors. Comparison of underground core, c'iannel, and grab sampling, suggests that core sampling tends to undervalue.

Jan 1, 1976

By E R. Ramanaidou

The presence of clays in channel iron deposits (CID) within the Pilbara region of Western Australia causes problems in the classification and subsequent processing of the iron ore. In particular, the presence of clay adversely affects the processing and ore metallurgical properties by increasing the amount of Si and Al. Iron ore companies are seeking new methods to quickly and objectively detect the type and amount of clay in these deposits. Traditional methods of clay quantification such as X-ray diffraction (XRD) and thermal analysis are time consuming and expensive. Reliance on bulk chemical techniques (eg X-ray fluorescence, (XRF)) to derive normative mineral abundances can give misleading results. For example, the replacement of Fe by Al in the structure of the iron oxide minerals, goethite and haematite, which dominate in CIDs, can be significant. Silicon can also occur in association with these Fe minerals. If not accounted for, chemical techniques may overestimate the normative abundance of clays. In comparison, reflectance spectroscopy in the visible-to-near infrared (VNIR) and short wave infrared (SWIR) wavelength range (eg 400 - 2500 nm) and Fourier transform infrared (FTIR) (6000 - 900 cm-1) analysis are non-destructive techniques that can provide rapid and objective mineralogical information. Both techniques are particularly suited to Al-, Fe- and Mg-OH bearing minerals such as clays. Kaolinite and, to a lesser extent, montmorillonite are the most common clay contaminants that occur in the Pilbara CIDs. Previous applications of VNIR-SWIR spectroscopy have demonstrated the potential of these methods in quantifying the clay mineralogy of CID ore. In this study, variations in the depth of diagnostic spectral adsorption features in the SWIR wavelength range of kaolinite and montmorillonite in standardised mixtures, with known proportions of clay, were well correlated to the abundance of kaolinite and montmorillonite, and to the clay alumina content (ie per cent Al2O3 û clay).

Jan 1, 2007

Dr David Dekker discussed the importance of a multidisciplinary approach to automation, the infrastructure required to support automation, and selecting the equipment for automation. Dekker stressed that automation involves a number of technologies. The mining industry is currently about part-way through the evolutionary process of achieving a fully integrated automation system. He pointed out that the final stages require parallel development of infrastructure such as mine communications. Technologies required for automation Automation systems consist of three parts: the gathering of information, the processing of that information, and taking action.

Jan 1, 1997

The evaluation programme and procedures develop- ed for Saindak porphyry copper-gold-silver- molybdenum deposits located in an isolated area in an extremely and region of Baluchistan are described in detail. Due to its isol .ted location, far removed from supply centres, harsh climate, paucity of water and non-availability of even unskilled labour, Saindak presented problems for which no ready made solution exist- ed. It is hoped that this Paper may be of some value to those in the LDCs who may wish to undertake similar ventures.

Jan 1, 1988

The large El Cerrejon coal open pit in north east Columbia has been developed over the last decade in a remote, entirely new mining area with hitherto unskilled inhabitants. Now over 200 pieces of heavy equipment operate with high reliability and availability due to successful theoretical training and skill improvement programs tuned to the specific reliability needs of the worksite and environment. The process of continuous improvement adopted promises further competitive advantages of the project.

Jan 1, 1991

By Goode A, Belby P, Wardell-Johnson M

Within a short time frame of just over two years Wirralie Gold Mine has been developed from a virgin geological discovery to an operating gold mine with a mine life of six years and a production rate of 50,000 oz per annum. Construction work on the 600,000 tpa single stage crushing, two stage milling CIP plant commenced in November 1987 and was completed some seven months later at an overall cost of $A25 million. Since commissioning in May 1988 the treatment plant has exceeded design tonnage, availability and recovery. A second expansion programme in January 1989 will increase plant capacity to one million tonnes per annum with associated bullion production of 80,000 ozs per annum.

Jan 1, 1989

By Watson D. F

P S B Stewart has rightly pointed to a possible obscurity in our paper on drilling patterns, viz. in comparing the improvement of a triangular drilling pattern over a square one, we used percentage improvements without always making clear their base. We hope, however, that other readers, like Stewart, have been able to understand the particular meaning from the context.Although different methods of estimation of an ore deposit will have different local bias (Philip and Watson, 1985), the critical relationship affecting the reliability of estimation of an unsampled location is the scale of local variation of the variable being estimated in comparison with the density and isotropy of sampling. This relationship overrides all other considerations.

Jan 1, 1985

Twelve years ago, Jeffrey Mining Machinery Division of Dresser Industries Inc. developed the 120H HELIMINER. This machine was the world's first fixed-drum continuous miner and soon became the standard among manufacturers of continuous miners throughout the mining machinery industry. This paper will first outline a brief history of continuous miner development, then discuss significant parameters which are essential to a successful continuous miner design, and finally describe a number of specific applications of Jeffrey continuous miners in a variety of materials, such as coal, potash, iron ore, and trona, around the world.

Jan 1, 1978

By Maconochie A. P

The copper-gold orebodies of the Ok Tedi project and located in an area of climatic and topographic extremes, where both the landforms and the rocks from which they have developed are so young that it may be said that geological and engineering processes are coincident.

Jan 1, 1990

By Williams RC

Overlying the coal deposits of the Sydney Basin are several lakes and other bodies of water. These include the Pacific Ocean, Lake Macquarie, the Tuggerah Lakes and the stored waters of the dams of the New South Wales Metropolitan Water Sewerage and Drainage Board. The coal beneath these bodies of water amounts to hundreds of millions of tons. Colliery workings have approached these areas of water and in some instances first 1"orkings of bord and pillar have taken place oi_eshh the water. he problem which now faces mine manage- and other interested authorities involves the determination of the maximum ;mount of coal which can be safely extracted from beneath the water. There are many factors to be considered including the depth of cover, seam thickness, geological details and strata movements.

Jan 1, 1972

In the 100 years since the formation of The Australasian Institute of Mining and Metallurgy there have been significant changes in all aspects of the mining industry.A number of the changes have been driven by technical evolution or necessity, others have been driven by developments in the application of the products produced from the mining of minerals. Other changes have been driven by shifts in community values.

Jan 1, 1993

By E Drueppel, F M. Meyer, P N. Martens, J P

The present study shows a calculation of the amount of copper contained in the initial reserves that remains un-extracted. The study is based on data of 271 producing copper mines and includes geological parameters, mining methods used and the processing recovery. Estimations disclose that approximately 25 per cent of the metal contained in the original reserves is not extracted. One third of this value can be attributed to mining, whereas two thirds are related to processing. However, values differ for different ore deposit types and mining districts.

Jan 1, 2003

Material hardness and environmental factors can limit or restrict conventional blasting techniques and this has led to advancements in the performance and efficiency of ripping. Not all materials can be ripped, however today's technology and experience can help make a reasonable prediction. A ripping versus blasting decision will depend on the total volume of material to be moved, the production capabilities and costs of the ripping tractor(s) and on the size and relative efficiency of drilling and Blasting.

Jan 1, 1995

By J H. Baker, P G. Beadle, J P. O&apos, Brien

In 1974 a preliminary study of the refractories industry in theRepublic of Indonesia was completed by Crown Lynn Consultants, a subsidiary of Cerarnco Ltd., on behalf of the Indonesian and New Zealand Governments. As a result of recommendations arising from that study the two Governments commissioned, in 1976, as a Bilateral Assistance project, an investigation into the potential of the refractories industry in Indonesia. Ceramco Ltd., was retained to carry out the study on behalf of the New Zealand Government. The Directorate-General of Chemical Industries, Directorate of Silicate Industries administered the project on behalf of the Indonesian Government. Indonesian counterparts to the New Zealand study team were provided by the Directorate of Silicate Industries.

Jan 1, 1978

By Brett D

Tailings disposal and water management are one of the most important environmental issues in mining projects. The nature and the method of disposal of the tailings will determine the long term environmental impacts and must be carefully considered at the planning stage so that final abandonment can be economically achieved. If not, long term and on-going treatment and amelioration may be required to achieve environmental standards. Final abandonment requires dam safety surveillance inspection to satisfy engineering stability and hazard requirements as well as environmental issues. Environmental issues include stability, as well as rehabilitation and long term contamination potential.

Jan 1, 1991

Over the 20 years to 1990 the Australian mining industry, presently worth some $A60 billion, generated a negative real rate of return (McDonald, 1992); not surprisingly under-performing the returns from bonds and industrial equities. Over this same period more than $A70 billion was invested in expanding the Australian mineral industry.

Jan 1, 1993

By Jepsen L, Gifford M, Thomas G. S

Mine planning requires careful prediction of both the head grade and tonnage of mineralisation. As part of the planning process, operators of the Murrin Murrin nickel/cobalt orebodies (located in the Eastern Goldfields province of the Yilgarn

Jan 1, 1998

Pan Australian Mining lid installed a milling and gold leaching plant designed to process 2 million tonnes per annum of breccia sulphide ore. This plant was commissioned in January 1989. Since commissioning, increased ore reserves have been established and the plant has been expanded by the addition of one ball mill and several tanks to increase the design capacity to 3 million tonnes per annum. This additional plant was commissioned in May 1990, bringing the total number of mills up to three, each 4.5 m diameter x 7 m long. The paper details how milling rates have been increased at the expense of grind size to increase the capacity of the original plant from 2 million to 3.1 million tonne per year rate before the additional ball mill was Commissioned.

Jan 1, 1991

Precipitation of inorganic compounds or metals from aqueous solutions can either be physical (crystallisation) or chemical in nature. Chemical processes are varied; they may be due to hydrolytic action, due to ionic interaction, or due to reduction (ie transfer of electrons). Transfer of electrons in reduction processes may take place homogeneously or heterogeneously. In the first case it may be ionic or nonionic in nature. Heterogeneous processes may be electrochemical or electrolytic. Examples of interest to hydrometallurgy are given.

Jan 1, 1993

Recent data contributions to New Zealand Mesozoic terrane geology confirm the consensus interpretation that New Zealand grew by the progressive addition of material by plutonic and accretionary processes along the Gondwana margin. The data also (1) emphasise the discontinuous but inter-related nature of these processes of continental growth, (2) better establish a direct Gondwana correlation of the Western Province and probable Gondwana provenance of at least some of the Eastern Province, (3) suggest specific times and places when passive or strike-slip rather than subduction regimes are recorded along the south Gondwana margin, and (4) potentially lead to interpretations emphasising parautochthonous rather than far- travelled relationships between many New Zealand terranes.

Jan 1, 1995