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The Wongawilli system of mining has been in use for over 30 years and has enabled high production rates and acceptable extraction ratios to be achieved in seams less than 4 m in thickness. A modification of the Wongawilli system has been developed to permit the use of a continuous miner and mobile equipment to extract a coal seam 6 m thick. Following physical and mathematical model studies the new mining method is now undergoing field trials at Collinsville, Queensland. Progress of the field trials to date has achieved 99 per cent extraction of the upper slice by remote control operation of the continuous miner and established the feasibility of installing resin grouted wooden dowels in the coal floor to reinforce the coal septum. The method is explained in the text. Monitoring of the goaf gases as an early indication of spontaneous combustion has been incorporated in the mining cycle by placement of tubes in the goaf as the face retreats and continuous analysis of the goaf gases made at the surface by the National Coal Board tube bundle monitoring system.

Jan 1, 1980

The objectives of this paper are two-fold. First, it will show what problems can arise when single estimated values are substituted for a distribution of values when evaluating an open pit mine project in the face of uncertainty. Secondly, it will show how the ability to deal with uncertainty and risk in mine project evaluation can have a significant impact on the ownersÆ and stakeholdersÆ investment decision-making. Here a new mine evaluation framework, the integrated valuation/ optimisation framework (named IVOF), is introduced as an alternative tool for mine project evaluation where uncertainty and risk are incorporated in the evaluation process.

Jan 1, 2009

The large increase in secondary industries in this country, during the war and post war periods, has caused a shortage of capacity for the production of merchant bar.To overcome this shortage, an expansion of rolling mill facilities has been undertaken by the Broken Hill Pty. Co. Ltd. A small, but modern, merchant mill has been erected at Kwinana in Western Australia and a strip and skelp mill is under construction at Newcastle. The latter mill will roll strip and skelp at present being rolled by the Newcastle 10 in. Merchant Mill, enahling this mill to concentrate on merchant bar production.The Kwinana mill was installed to supply the Western Australian market. This state has a small population (approximately 658,000) and is not at present highly industrialised. It was necessary, therefore, to design a mill which would be capable of producing a wide diversity of sections and could be expanded as the demand increased. To begin with capital expenditure had to be kept within reasonable bounds. The design work for this mill, with the exception of a few specialised items of equipment, was carried out at Newcastle.All design work for the Newcastle mill was carried out by the lVIorgan Construction Co. of America. Although initially intended for rolling flat. products, the designers were asked to make the mill as flexible as possible, so that should the market for flat products decrease, this mill with additional equipment could undertake the rolling of medium sized sections.

Jan 1, 1957

Owing to the number of chemical processes now in use for the separation of metals from their ores, and the consequent employment of chemicals at the mine, it is sometimes necessary to be able to produce them on the spot. This particularlyapplies to sulphuric acid which may be required for the manufacture of chlorine and of sulphate of copper, or for the treatment of'sulphides and other purposes. It can be made from brimstone for rather less than £3 per ton, but when delivered to any distance from the works, the cost of packages and other charges would amount to more than the value of the acid.I hope therefore, that to any of the members of the Institute who may find it necessary to make sulphuric acid for their own requirements an outline of the process, and some details of the plant etc may be useful, and perhaps lead to their devising improvements, mechanical or otherwise. Though acid can be made from pyrites in Europe for about 15/- per ton, it is probable that for most metaIIurgical purposes the quantity required. and the uncertainty as to how long it would be needed, would make it advisable to spend as little as possible on plant, and so use brimstone, though more expensive, I have therefore given no details of pyrites burning, which is very fully treated by Prof, Lunge in his work on " Sulphuric Acid and Alkali."

By F N. Baez

This paper supplements a keynote address prepared for the MassMin 2016 conference on mass underground mining methods, including block, panel, inclined and sublevel caving. It advocates for a new cave mining paradigm that takes advantage of a number of new and disruptive technologies or innovations that have evolved over the last 15 years, some of which were initiated by major mining companies such as Codelco. The paper will address the challenges that the industry will be facing in the future as well as possible solutions. As background, the paper summarises the challenges that the industry has faced in the past and how such challenges were addressed. The author acknowledges that given his more than 30 years of experience with Codelco Chile (operations and corporate), aspects of his intelligent mining concept have no doubt been influenced and have matured during his invaluable time with Codelco also as the Head of Technology and Innovation. In the paper, he uses some of the innovations developed within Codelco and by the Chilean Government to illustrate the concept of ‘intelligent mining’.CITATION:Baez, F N, 2016. ‘Intelligent mining’ – the way of the future, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 3–8 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

The Peelwood district of New South Wales is located some 65 miles south of Bathutst on the Tuena-Crookwell road. A number of occurrences of lead-zinc-copper ore are known from this district but only three mines, Peelwood, Cordillera and Mt. Costigan, have achieved any significant production. The purpose of the paper is to describe the mineral composition of sulphide ores from these three localities.HISTORYNo published information on the geology of the Peelwood area is available. Came (1899) reports that, at the time of cessation of mining operations in 1888, the Peelwood mine had produced some 600 tons of copper metal and regulus, the Cordillera mine had yielded 9000 tons of ore at the recoverable grade of 2·5 per cent Pb, 2·5 per cent Cu, 90z/ton Ag and 1 dwtjto:p. Au, but that no production figures were available from Mt. Costigan. No further work was carried out on these properties until 1951 when the Electrolytic Zinc Company of Australasia instigated a programme of geological mapping and exploratory diamond drilling (Whitten, unpublished data, 1953). The Peelwood district was recently mapped by Mutton (unpublished thesis, 1960) from whom the following geological summary account was taken.GENERAL GEOLOGYAll rocks in the Peelwood area belong to a series of interbedded fine grained sediments and volcanics that are thought...

Jan 1, 1961

By J R. Lang, J K. Mortensen

The Canadian Cordillera contains numerous classic porphyry deposits and several unusual subtypes, including the alkaline suite of porphyry Cu-Au deposits and the Tombstone magmatic suite and associated Au¦W deposits. The alkaline suite formed in collisional settings in island arcs whereas the Tombstone suite was emplaced in an active fold and thrust belt in a continental arc. In addition to different regional settings, these suites differ in the type of underlying basement, metallogeny, and the styles of mineralization. Both magmatic suites were emplaced over short intervals, probably in response to specific tectonic events. In the case of the alkaline suite, the tectonic event promoted magmatic processes suitable for the formation of porphyry Cu-Au deposits. The tectonic environment is less well constrained for the Tombstone suite, but the result was the formation of distinctive porphyry and intrusion-related Au¦W deposits.

Jan 1, 1995

Conservation and environmental issues are raising their profile with respect to both demand restraint and electricity supply options. In New Zealand, conservation pressures and energy efficiency need to be seen in relation to the supply system currently in place which has capacity for economic supply of electricity in quantities substantially in excess of the current market. Consequently, energy efficiency and conservation need to be interpreted in relation to the supply system as well as in relation to end use. The relationship between the environment and conservation is strongest when new generation is required. New Zealand's electricity supply system consists of a large proportion of hydro production and this has significant environmental benefits when considered in relation to concerns of global wanning and the greenhouse effect. However, environmental trade-offs in supply options need to take account of both the efficiency of electricity end use, the trade-off between hydro and thermal generation and the inter-regional effects of shifting development options from one region to another. The Electricity Corporation has a high level of consciousness with respect to environmental and conservation issues and this paper demonstrates its own moves to maximise energy efficiency and illustrate the environmental trade-offs for supply.

Jan 1, 1990

By Clarke P. E

At the end of the recent war, reports became available from Europe of the use of tungsten-carbide inserts in percussion rockdrill bits. These bits were used with small size rockdrills, so that the only advantage gained from the use of the harder, abrasion resistant, tungsten-carbide appears to have been the greater life of the bit. Larger machines, such as used in Australia in conventional practice, had to be discarded to protect the relatively brittle tungstencarbide inserts and the vulnerable bonding with the bit body.As it had been found in machine shop practice that some grades of tungsten-carbide had been produced with considerably improved toughness, it was decided by Gold Mines of Australia Ltd. that drilling practice with tungstencarbide bits warranted detailed examination under Australian conditions, and that drilling tests should be undertaken at Morning Star (G.M.A.) Mines N.L., for which it acts as General Manager and Consultant.These investigations progressed through three stages:1. Preliminary Investigations and Tests.When the investigations were initiated no commercial bits were available in Australia, and manufacture was commenced with improvised equipment from virtual scratch. These early tests indicated that the use of 3 in. bore rockdrills in conjunction with tungsten-carbide insert bits was a 'possibility, and that it was unlikely that a small bore...

Jan 1, 1950

Effect of Lattice Impurities on Electronic Properties and Surface Adsorption of Sphalerite - A Density-Functional Theory Study

Sep 13, 2010

By J Fraser, M Scoble

Within the past decade, incidents of mining–community conflicts have grown dramatically and represent one aspect of a phenomenon known as social risk. Research published in 2014 indicates that a lack of social acceptance is now a leading and costly cause of delays for mining projects.The rise of social risk, complemented by the need to earn the trust of an increasing number of stakeholders so that mining projects can be developed effectively, is problematic for the industry. Conflicts are occurring in situations where companies are fully compliant with regulatory and legal requirements, despite initiatives by mining companies to earn social acceptance and despite the proliferation of tools to support corporate social responsibility. Intensifying the impact of social risk is the fact that it has increased during a time in the global mining sector when companies have had to grapple with declining commodity prices, increasing capital costs and debt levels and the challenges of mining lower-grade deposits.This paper will explore a hypothesis that in today’s interconnected society, social risk in the mining sector constitutes a legitimate business risk that must be managed strategically. The reality facing mining companies is that information, once considered confidential, now travels quickly on social networks and via a growing number of groups and individuals that have earned a legitimate right to be classified as stakeholders in projects that affect their communities. To be successful, it is suggested that companies will benefit from increasing internal collaboration and providing training to equip teams to mitigate social risk to mining projects and protect reputation capital. The paper is based upon PhD research being undertaken to assess the points of intersection between social risk and social responsibility during the construction stage of greenfield mining projects.CITATION:Fraser, J and Scoble, M, 2015. Mining–community conflicts – can the future mining sector transform social responsibility?, in Proceedings Third International Future Mining Conference, pp 159–168 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By Mills R, Shannon W. T, Finch J

As an extension to investigations into methods of upgrading the Iitania content of ilmenite concentrate from beach sands using 100 g/day, a small pilot plant treating 23 kg/ day of ilmenite was used.In the pilot plant the iron oxide in the ilmenite was reduced to iron at 1200°C using carbon (coal/char) without melting the material, using a tunnel kiln heating cycle, the charges contained in saggars, The iron was then separated from the titania fraction by ball milling, wet magnetic separation, and screening. The resulting magnetic product was high in iron (about 80 per cent Fe) and the non-magnetic product high intitania (about 70 per cent TiO2).From this trial sufficient data were obtained to enable the preparation of a flow sheet for a plant producing 62,300 tonnes/year total products, and an estimate of costs to be made. This has shown that for an estimatedcapital expenditure of nearly $6,000,000 and annual production costs of about $4,000,000, the cost per tonne of high titania product (76 per cent TiO2) would be nearly $70.

Jan 1, 1977

The distribution or the userul minerals or Tasmania is so closely connected with the geological structure of the island that it will be convenient to briefly recapitulate the principal ract or its geological history, before describing the ore and other deposits. In many cases these present features which are very puzzling in the absence of knowledge of the structure of the districts in which they are found and in all cases it is of benefit to mining engineers to be acquainted with the main facts of the geological·history of the regions in which they have to carry on operations. Moreover, in speculating as to the origin of lodes and other deposits, we have constantly to rerer to the crumplings or the earth's crust by mountain-making movements, and to the igneous rocks which have been thrust throngh the other strata, to explain the origin or the lode fissures, and this discussion cannot be carried on without knowledge of local geology.The oldest rock yet met with in Tasmania are of Archooan age, and consist of highly crystalline quartzites and micaceous schist. They are most extensively developed towards the western side ot the island, forming a belt parallel to the West Coast from South-West Cape to Cradle fountain; but they also crop out here and there to the west and northward of this belt, where the covering strata or later age have been denuded away. Though not seen in situ in the eastern part of the colony, the abundance or pebbles derived from this formation in the conglomerates of the coal measures shows that it must in those day have formed land surfaces there also, and makes it likely that the archooan strata exist at no great depth: below many of the beds of later age now occupying the surface. Lying unconfortably upon these highly metamorphic strata we find next an extensive series of subcrystalline metamorphic conglomerates, grits, sandstones, slates, and limestones,of Cambro-Silurian age. These are well seen in the Gordou River Basin, along the West Coast Range, aloug the North Coast, and in the goldfields of the north-eastern portion of the colony. They are much broken by later intrusive rocks, and covered by younger rormations, but the series is spread more or less over the whole island.

By R J. Holmes

The procedures and equipment used for sampling iron ore process streams have generally improved in recent years. However, there are a number of areas where significant issues still commonly occur, including sampling high capacity streams, sample cutter design and operation, division of primary increments at the secondary sampling stage, the performance of crushers installed to reduce the particle size prior to sample division, and the sample mass that is retained at each sampling stage. These issues of non-conformance with correct sampling principles are caused by factors such as increasing the speed and loading of conveyor belts to increase throughput, which changes the trajectory of the ore stream and may result in an inability of the sample cutter to handle the increased flow rate without sample loss. Failure to sample the entire primary increment stream at the secondary sampling stage is also a common issue as well as failure of crushers to provide crushed products of the required particle size due to ongoing maintenance and/or adjustment issues. These common pitfalls can all be addressed through careful attention to detail.CITATION:Holmes, R J, 2017. Common pitfalls in sampling iron ore, in Proceedings Eighth World Conference on Sampling and Blending , pp 261–264 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By C Johnstone

Project management is not a task to be undertaken lightly. Mining projects generally present even more challenges due to ChinaÆs remoteness and complexity. Having experiences in project management in the West is certainly an asset, but China can present the uninitiated with any number of headaches. To undertake a project there can have many problems that are unique to China. For the last 15 years, China has seen an increasing number of foreign capital investment projects in the mining industry. Practices involved in mining project development have experienced/are experiencing an evolution. Since 1996, Sino Gold Mining Ltd has delivered three mines in China, ie Jianchaling Gold Mine, Jinfeng Gold Mine and White Mountain Gold Mine. Through the work, Sino Gold has established a solid knowledge base and a capable and skilful workforce in effectively undertaking mining projects in China. This paper is concerned with the experiences accumulated so far by Sino Gold in project management in China. An overall review is conducted regarding the reform of the mining project development in China. Opportunities and challenges are highlighted within the political, economic and culture context. Brief summaries of the development of the three gold mines are presented.

Jan 1, 2009

By Haukka M. T

A new low-dilution fusion method which has been successfully used for accurate determination of the major oxide components of silicate rocks, is applicable to rapid, accurate determination of trace or minor eiements in mineral exploration samples. Limit of detection is in many cases less than 5 ppm. Either rapid, approximate measurement and calculation methods (suitable for geochemical exploration), or more accurate methods (applicable to orebody evaluation studies) may be used.Rapid methods are described for nickel in rocks and sulphides containing 10 ppm to >2 per cent Ni, and for gallium. The rarely-determined element gallium is an example of a constituent which may be easily investigatedby XRF using the LiB02 fusion disc, which is a permanent, easily-stored analytical sample available for later rapid or accurate analyses. The method is applicable to over 30 elements at levels encountered in mineral exploration.

Jan 1, 1978

With the employment of a system of ore pillars to support the hanging wall during the mining operations at the North Mine, it was found that, when the stopes were worked out and the pillars remained intact, the main footwall drives developed an undulating longitudinal section due to the shrinkage of the filling in the worked out stopes.These depressions collected water, which made the footwall drives very wet under foot, and everitually worked its way into the pillar workings and the levels below.Water was also finding its way into the shafts because of the silting-up of the level drainage systems and, as both the shafts are down-cast, this tended to increase the humidity of the air entering the mine.To overcome these troubles it was decided to try a system of siphons as a method of subsidiary drainage.SYSTEM AT PRESENT IN USE.All drainage water is collected as near to its source as possible, run into a sump in an adjacent low lying part of the level, and continuously removed from these sumps by a siphon system.Each level has its own system. Water is collected from the sumps by a 1-in. pipe and delivered to a pipe running the length of the level along the back of the footwall drive. At the shaft the pipe is increased to...

Jan 1, 1938

By G Dunstan

The Ridgeway gold mine has been an enigma of the international underground hard rock community for nearly 20 years. It nearly didn’t eventuate as it was more than 500 m below a farmer’s paddock in Central New South Wales when the exploration team, looking for open pit deposits, got a sniff on its last attempt and then drilled the high-grade discovery hole. It took separate studies to find an economic mining approach. Newcrest, then a mid-tier mining company, took the venture that set it on a path of growth and built what was to become the backbone of the company for the next 15 years.The initial mining method was sublevel caving (SLC) for the upper 300 m of the orebody. The nameplate production rate for the SLC was 4 Mt/a, which was reached in June 2002 shortly after the commissioning of the materials handling system. The ultimate production rate was subsequently lifted to around 6 Mt/a through a series of innovative and efficiency initiatives. In June 2007, approval was granted for the development of a block cave (BC) operation to extract the ore reserve situated immediately below the existing SLC operations, Ridgeway Deeps. The BC was designed at approximately 6 Mt/a to match the concentrator and a systematic improvement process through the entire underground system again saw delivery rates consistently around 10 Mt/a.In line with the production rate increases, Newcrest was also committed to advancing caving knowledge through a number of targeted research and development experiments and new processes. These were primarily related to improving cave ore recovery through systematic draw marker trials, cave propagation through preconditioning techniques with associated monitoring systems. New technologies were also developed to improve the safety and efficiency of the mine through data collection, cave establishment techniques, production dispatching and autonomous loading.CITATION:Dunstan, G, 2016. The truth is stranger than fiction – the story of Ridgeway gold mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 19–30 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

Interest in mining narrow, vein-type ones has increased world-wide during the last few years despite the fact that prices of metals have not risen in proportion as production costs of mining, such as labour and energy. In many mines, where narrow ones are mined, the mining technique and equipment used have been poorly mechanised. The mining methods have been cut-and-fill or shrinkage stoping. Pneumatic jack-legs have been used for drilling and slushers have been used for loading. The methods that have been used can be called the 'first-generation' methods. Work has been very hard for miners. It has been dangerous and exhausting. Production volumes of mines, and a s a result of that, also profits have been low.

Jan 1, 1990

GOLD has played a part in the development of Australia. The total yield exceeds SIX hundred million pounds sterling, while the glamour of gold-mining and the unfailing demand for the product have enhanced its influence. The production is still considerable, but the yield is less than one-quarter of that twenty years previously, while the number of men employed has dropped from 70,000 to 11,000. Not only has there been a marked decline in production, but it is anticipated that thisdecline will continue, and continue more markedly. It is therefore desirable to ascertain the causes of the decline and inquire into means for diminishing or preventing it.The problem under discussion is far from being only local. Finlay states: The grand feature of the history of the business has been the progress of an economic cycle unfavourable to gold milling. The USA yield fell from $101,000,000 to $44,000,000.South Afriea has for some time produced one-half of the world's gold; yet in the Mining and Scientific Press of 11th February, IH22, General Smuts is quoted as saying that if the premium disappeared entirely 24 out of 34 mines would shut down. The solution, however, might be either general eg, a great advance in the metallurgy of gold; or local eg, a bonus; but before discussing any of the proposed solutions it will be advantageous to review the situation.STATISTICS OF THE PAST AND PRESENT PRODUCTION OF THE WORLD AND OF AUSTRALIAThe inquirer soon finds that there is a good deal of uncertainty, and that much care is needed in collating figures. In some cases a considerable part of the output is not officially reported, and returns...

Jan 1, 1924