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Deposits of manganese oxides and silicates in the Tamworth area were re-examined. The major deposit at Danglemah consists chiefly of rhodonite and the rare silicate tephroite. It is considered that the manganese was deposited with the original sediments, the silicates being formed later during the intense folding and low-grade metamorphism of the enclosing rocks.INTRODUCTIONMany small deposits of manganese oxides and silicates occur along a belt of eastern New South Wales and Queensland.Some fifty occurrences, most of which have been subject to mining activity, were described by Lloyd (1943) and some of this information was summarized by Knight (1947). The ores have been mined on a small scale since 1884. Small supplies of battery grade ore were won from a number of deposits, while larger quantities of metallurgical grade were sold to the steel industry. Maximum production was in 1918, when 6,500 tons were mined.The siliceous nature of many of the ores and their occurrence in the neighbourhood of granite batholiths led earlier investigators to consider the deposits to be of hydrothermal origin, associated with the granite intrusions. The present work questions this viewpoint.In this investigation, three of the chief deposits in the Tamworth area were seen. These were at Danglemah, which is being mined at present, and Mount Jasper and Manganese Mountain, which were mined in the past. The Danglemah mine is the most accessible and yields the best material...

Jan 1, 1962

When Australian voters elected a Labor Government in March 1983 the value of the Jabiluka uranium deposit as an asset of Pancontinental Mining Limited effectively evaporated overnight. The day before the election, Jabiluka was Pancon's principal asset, with the Company's 65% stake in the deposit having a market value of the order of $US1 billion. This value had been set by an agreement reached with a potential customer, who was prepared to pay $US150 million for 10% of Jabiluka. The months before the election had been the culmination of ten years of unremitting effort to bring what was then the world's largest reserve of high'grade uranium ore into production. These efforts had included two and a half years of negotiations with the local aborigines, as well as exhaustive environmental studies and conceptual mine planning. All domestic approvals required to develop the Jabiluka deposit had been given to Pancontinental and marketing efforts had successfully placed about 50% of the expected uranium production with overseas utilities. It appeared that Jabiluka was about to emerge as one of the world's great mining enterprises. The election of a government with an anti-uranium policy stopped Jabiluka dead in its tracks. Pancontinental's largest asset had effectively become worthless and the Company appeared to be facing a bleak future.

Jan 1, 1987

Cadmium occurs in the Broken Hill Lode essentially as a camouflaged element, substituting diadochically for zinc in the sphalerite.Analyses of a series of zinc concentrate flotation products, prepared from samples of ore taken at intervals throughout the developed lengths of the several orebodies forming the lode, have revealed a pattern in the distribution of cadmium relative to zinc. This pattern appears to reflect the temperature and order of deposition of the several orebodies, and the direction of movement of the mineralizing solutions.INTRODUCTIONThis investigation into the distribution of cadmium in the several orebodies of the Broken Hill lode was undertaken by the Mineragraphic Section. of C.S.I.R.O. in conjunction with the Broken Hill Geological Research Committee, as part of a study of Broken Hill mineralization.It arose from the examination of cadmium and zinc assays supplied by Mr. T. A. Read, Chief Metallurgist of the Broken Hill South Ltd.; of experimental zinc concentrates prepared from localized samples of the No, 2 and No. 3 orebodies in the Broken Hill South Mine. These assays suggested that the two orebodies were characterized by distinctive ZnjCd ratios.In view of the possible sigmficanc'e of such a difference, comparable data were sought from each of the other mines. The necessary samples of ore were collected by the geological staffs of the several mines. The preparation of separate zinc concentrates and lead concentrates from these samples, and their assaying, was conducted by Mr. Evan Hardy, for the North Broken Hill Mine, and its assodated leases, and by Mr. D., Swan, under the direction of Dr. J. C. Nixon, for the Zinc Corporation and New Broken Hill Consolidated Mines. Additional tests on the Broken Hill South Mine were made by Mr. C. W. Reilly, under the direction of Mr. T. A. Read. The samples were...

Jan 1, 1955

New Zealand China Clays produces a unique halloysite clay product at Matauri Bay, Northland.   The company has licences over four deposits that were derived from the weathering of rhyodacite domes. Clay is mined and processed from two of the four deposits and is refined using a complex process based on gravity separation.   The product is almost entirely exported to niche markets in 24 countries. The main market is the fine ceramic industry where the product is used as a component in the manufacture of high quality porcelain and bone china bodies. The use of halloysite in these bodies gives the manufacturer the ability to achieve high whiteness and translucency. The other major market is for use in technical ceramics, where the product is sought after due to its high purity, fine particle size and stability at high temperatures.

Jan 1, 1997

In a previous paper the writer dealt -with the jasper bar formations and their relationship to the structural geology of older pre-Cambrian rocks in the goldfields districts of Western Australia (24). He has pointed out in this ahd other papers that jasper bars, or banded iron formations, banded hematite or ,magnetite quartzites, jaspilites and related banded ferruginous or non-ferruginous cherts, occur in abundan'ce in the Older Greenstone Series of Western Australia (22), (24), (26). They are considered to represent special forms of banded ferruginous sediments, and are usually fpund in the field interbedded with more or less metamorphosed pasaltic 01' andesitic lavas and tuffs, now amphibolites, together with occasional thin bands of normal pelitic sediments, which go to make up a large proportion of the Older Greenstones in thfs State (26).Great thicknesses of fiat-bedded ]:landed ferruginous cherts are also found associated with cherty' carbonate rocks; quartzites, shales and thin-bedded dolomite whicIi constit'ute the Nullagine (Pl'oterozoic) system in the northwest of Western Australia. In the Hamersley Range district these banded ferruginous chert beds are the hosts of important deposits of blue amphibole asbestos.In the paper mentioned above brief reference was> made to the importance, of geological structure in relation to economic geology, particularly in the goldfields regions of Western Australia, and it was shown that jasper bars may have an important role in the study of 'the structural geology of many of these regions. Of possibly more immediate economic importance is the part that these rocks play, both directly and indirectly, as host rocks for mineral deposits-the chief of Which are gold, iron ores, blue asbestos, and manganese ores. The blue asbestos bearing banded iron formations mentioned above are confined to the younger pre-Cambrian Nullagine formations. They have been described in detail elsewhere (23). In this paper it is proposed to discuss the economic geology of the jasper bars found in the older pre-Cambrian series.The jasper 'bars have in themselves little or no intrinsic value except perhaps some of the more highly coloured and banded varieties which may be utilised for ornamental and decorative purposes. Probably the best known of such varieties is the so-called "marble bar;" a belt of, strikingly coloured banded chert occurring just south and west of the famous town of that name (see Fig. 1t). This consists of a hard, very fine, even-grained rock with alternate individual stripes varying from the thickness of a sheet of paper up to an inch or more in width, and ranging in colour from clear white to yellow, from various shades of pink to brilliant...

Jan 1, 1943

Beaches contain the residue of eroded rocks which have resisted weathering, and it is common to find in all beaches some of the harder, heavy minerals. The natural sorting action of waves and winds tends to concentrate the heavy minerals into banded deposits.The value of such deposits is extremely variable. Even amongst the more concentrated deposits, the principal minerals, in the vast majority of cases, are magnetic, titaniferous magnetite and other forms of iron oxide, which, in the present state of mineral economics and technology, are of little or no value.Valuable minerals of fairly common occurrence in beach sand deposits are rutile, zircon, ilmenite, monazite and chromite, and each of these minerals, as well as others of less common occurrence, is obtained from beach deposits in various parts of the world.Along a stretch of 300 miles of coast from Coff's Harbour in New South Wales to North Stradbroke Island in Queensland, occur unique concentrations of heavy minerals. The principal minerals which occur are rutile, zircon and ilmenite, and for some years these deposits have contributed half to three-quarters of the world's consumption of rutile and zircon 1, ,2. The only other notable beach sand concentrations in Australia are at a number of places in the southwest of Western Australia, where deposits containing highgrade ilmenite are being developed.

Jan 1, 1950

The mineral resource that a mining company has access to, represents the majority of the embedded value that exists within the company, as well as the competitive advantage that the company has over its peers. However, the real value is only realised once effective mining plans have been put in place, which optimise the extraction of the resource, and add measurable value to the company. The concept of mineral resource management (MRM) has been developed in South Africa, to ensure this optimisation happens in an integrated and quantifiable manner, such that value is added and risk is reduced, resulting in bottom line improvement for the stakeholders of the business. This paper describes the process of mineral resource management, and draws on successes and failures of various companies, to illustrate how it should be implemented, and what measures should be put in place to ensure its success. This requires a fundamental re-appraisal of the way in which mining companies plan and execute their businesses, and focuses attention on real value adding activities and behaviour through the use of economic value added as an appropriate metric by which to measure real value and risk. Specifically, the paper focuses on these aspects as applied to planning models and processes, exploration activity and risk management, to ensure operational and project success.

Jan 1, 2006

By A M. Ebbels

"Underground mine scheduling decision-making has been based on production requirements, equipment productivities and the mine planner’s instincts on the best scheduling strategy for the mine to optimise the net present value (NPV) of a project.In the last few years, innovative software has been developed to optimise underground schedules based on NPV. The schedule optimisation tool (SOT) allows the user to set up scenarios based on grade, metal content, capital and operating costs.This paper discusses the results of two case studies undertaken using the SOT software to optimise the NPV of the projects.In each case study, the SOT software has been applied in two ways:using the original mine planner’s scenario and determining whether the NPV could be improved by changing resource capacitieschanging the scheduling goals to determine whether a different mining strategy would have a better NPV outcome.The outcomes of the case studies demonstrate that the mine layout and design were contributing factors to the overall improvement of the NPV and that SOT has a more noticeable impact on the NPV of projects where less sequence constraints are required, such as geotechnical sequencing and access development.CITATION:Ebbels, A M, 2016. Optimising underground mining strategies, in Proceedings Project Evaluation 2016, pp 60–65 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016

In this year marking the centennial of the Geological survey of Western Australia, it is appropriate that we should review the value of the contribution of the Survey, and Australian Geological Surveys in general, to the exploration industry. Most geological surveys in Europe and North America had their origins in the first half of the 19th Century when the burgeoning Industrial Revolution was demanding the identification of new sources of coal and iron ore. Australia, as a young nation, essentially dependent on an agricultural and pastoral industry, and with already discovered vast coal resources in Eastern Australia, had, no great need to explore for new mineral resources. However, with the discovery of gold in 1851, the mineral potential of the country became apparent to the whole world and the first Geological Survey in Australia was set up in 1852 in Victoria under A.R.C. Selwyn. After a number of false starts all Australian States had an established Geological Survey by 1900. It is hard to assess the contemporary value of the early work of the Geological Surveys with respect to exploration, almost all major mineral discoveries were made by prospectors and most mining companies had little time for geologists - although the Chamber of Mines in Western Australia in 1910, did recommend that the Geological survey be granted an additional ten thousand pounds over two years to map all existing goldfields and the country between them, and produce a reconnaissance map of the area east of a line between Wiluna and Edjudina as far as the South Australian border!

Jan 1, 1988

By C I. Edwards

Phosphorous is typically present in iron ore either in the mineral apatite, Ca5(PO4)3OH, or associated with the goethitic fraction of the ore. In this paper, we present results that show that phosphorous associated with the goethitic fraction can be removed with a heating pretreatment around 300 176;C for 1 h, followed by a caustic leach with 1 - 5 M NaOH, or a leach with sulfuric acid at pH 0.5. The heating pretreatment is considered to dehydroxylate the goethite to form a haematite intermediate phase, ‘protohaematite’, that reacts during the leach making the phosphorous accessible to the leachant. In the acid leach, ten to 15 per cent of the sample was dissolved to obtain a leach product with 0.08 per cent P. In the caustic leach, as no weight loss occurs, it is proposed that iron species associated with the protohaematite have either not dissolved or have reprecipitated at the high pH values of the leach.For an ore containing apatite as the source of phosphorous, a leach with sulfuric acid dissolved the apatite, lowering the phosphorous levels in the sample. The sample treated contained carbonate minerals (including siderite) that also reacted with the acid, and in practice a balance between the dissolution of the apatite and the carbonate minerals may be needed to minimise acid consumption.

Jul 11, 2011

By M Podreka, P Merry, L van den Berg

Anglo Gold AshantiÆs Sunrise Dam operation is located in Western Australia approximately 55 km south of the town of Laverton. Currently, the mine is producing from both its open pit and underground operations and is planning a significant step change in underground production as the pit phases out. The mine ventilation system is arranged in three independent ventilation districts: Astro, GQ and Cosmo. The future ventilation infrastructure requires significant upgrades to keep up with the increased tonnage. In the short term, increased production is planned for the GQ district as well as for Vogue, which is an extension in the Cosmo ventilation district. In the long term, however, Vogue is likely to become the centre of attention for mining activity.This paper explores several ventilation scenarios which include upgrading the existing fan stations, rentals, establishing a common ventilation backbone, and establishing new upcast infrastructure for GQ to support the short-term production increase. These developments were modelled using ventilation network simulation software to determine airflow distribution and fan operating points for each option. For the GQ area, with its short-term increase in production, each option is evaluated for total owning cost by considering capital and operating costs over a three-year period. For Vogue, which is to become the main focus of mining in the future, a different strategy is followed in analysing the ventilation requirements. Instead of considering different short-term options, a number of staged upgrades are considered to achieve the desired production rates.This paper summarises the planning criteria, airflow requirements, ventilation infrastructure requirements, and economic analysis associated with the conceptual ventilation system design. It highlights how the best short-term ventilation infrastructure upgrades can be selected when considered in isolation but highlights that long-term production planning can have an effect on the decisions made in the short-term.CITATION:van den Berg, L, Podreka, M and Merry, P, 2013. Sunrise Dam short- to long-term ventilation planning, in Proceedings The Australian Mine Ventilation Conference , pp 107-114 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

We are all no doubt aware that with today's high costs it is more important than ever to get the maximum possible return on capital invested in the mining industry. Screening is an important and often costly process in the size classification of industrial minerals and for this reason alone it is essential for both managers and operators to fully understand what type of screening equipment is best suited for a particular application and why. The advent of elastic materials such as rubber and polyurethane have added a new dimension to the process of screening. It is important to understand why the physical properties of these materials can be of benefit in the screening process, and recognise which type of screening applications best take advantage of these orooerties.

Jan 1, 1984

By W Mez

The German mining industry uses different residues for backfilling and stowing. A hydraulic pipe conveying technology for these materials has shown advantages for the transportation into the mine. Pipeline conveying systems are able to bridge long distances, they save room within the underground workings and they save staff and costs. Absolutely necessary for successful use of the hydraulic conveying technology is the knowledge about the unusual non-Newtonian flow properties of solid/liquid mixtures like pastes and slurries. The flow resistance of these materials cannot be described easily by one viscosity. Owing to a yield point and a pseudo-plastic behaviour the viscosity changes with the shear rate and with the streaming velocity inside the pipe. Also these flow behaviours depend very sensitively on the liquid/solid-ratio, often so dramatically that gravimetric or volumetric dosing equipment is not in a position to control the production of backfill pastes. Quality changes of the solid raw materials (particle size distribution, density, mineralogical composition) lead to additional difficulties. The first experiences with hydraulic backfilling plants were troubled by plugged pipes, a bad backfill quality caused by unnecessarily high water content and high costs for chemical binders to solidify the backfill. The installation of viscosity controlled paste production leads to success with the hydraulic backfill technology. A development of the DMT, a bypass pipe-viscometer, has been the key technology. The system is able to analyse on-line, difficult, sticky and abrasive substances and determine their non-Newtonian flow properties. Because the system measures real physical values it is in a position to pre-calculate process relevant parameters like the pressure drop of the backfilling paste in the conveying pipeline. Newer types of the viscometer system also measure the slurry density and calculate its composition. These systems have proven a success controlling backfill paste production plants. They offer a secure prevention of pipeline plugging and a production of high quality backfill pastes with a water content as low as possible.

Jan 1, 1998

Education for the Mineral Industry in Australia developed in an uncoordinated but effective fashion till the mid 1960's, with recognised quality in graduates, with output matching demand, and with industry needs being fulfilled. Then in the space of a further 20 years, as company structures expanded, as the number, complexity, and costs of mineral projects escalated, as educational facilities, costs and politics increased, as community perceptions and aspirations changed, as government control of minerals and education increased, and as mineral sales cycles and markets fluctuated widely, the very fabric of Australian Mineral Education fell in tatters. Extractive Metallurgy Education suffered most in this collapse, and no compre- hensive remedies have been initiated. We are all the losers. In the 1990's, the extraction of Australian minerals and metals will increase in international significance, and the education of Extractive Metallurgists must meet this need. After examining the current situation, a series of management strategies are proposed to enable Extractive Metallurgical Education to survive and prosper in the next two decades and beyond. These strategic proposals involve industry, the government, the educational bodies, and individuals, in a range of short and long term objectives, policies, and actions.

Jan 1, 1984

By T Burns, P Savory

In 2013, Rio Tinto Iron Ore (RTIO) produced 251 Mt from 15 mines in Western Australia. Throughout the mines, Ore Reserve models are used for long-term and medium-term mine planning. Grade control data aids the accuracy of short-term planning. Reconciliation of models with grade control data is important for maintaining confidence in predictions from the models, understanding the limitations of the models, and identifying issues that may require further work.There are a large number of sites and models, with more than 200 professionals involved in different parts of the reconciliation process. Regular meetings of all involved and enabling effective communication are important in the reconciliation process.Reconciliation data is gathered and processed through a web-based system; Grade Block Reconciliation System. This system cuts each grade block against the required model, stores the results, and allows users to view and analyse the data. Development of this system has occurred over a number of years and all Rio Tinto Iron Ore mine geologists and resource geologists now use it as standard to report reconciliation results. The results can be viewed in many ways including by different time periods or benches. Graphing the results assists identification of trends. Centralising and standardising reconciliation has allowed easier comparison between sites. Flexibility in the system allows users to customise reports to manage issues unique to their particular site.In parallel with system development, substantial effort has been put into ensuring mining professionals get together to discuss and understand reconciliation issues. To facilitate this there are now regular sessions, including site visits. Issues are assessed on a case-by-case basis and decisions on how best to address the issues are made by the relevant stakeholders. Reconciliation reports and action plans are revised each quarter.CITATION:Burns, T and Savory, P, 2014. Reconciliation of orebody model predictions – system and people, in Proceedings Ninth International Mining Geology Conference 2014 , pp 367–376 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

This paper explains why the valuation of mining assets is often a very different exercise from the valuation of the shares in the mining company which owns those assets. The fundamental reason for this is that mining assets, and the shares of the company which owns those assets have different risks. In order to properly value mining securities it is essential to: ò ensure all the different risks and other factors which impact on the value of the mining assets and the value of the shares are taken into account; and determine the extent to which the different risks and other factors are addressed in the value of the mining assets and the value of the shares so as to avoid double counting or not counting at all. If the alternative, but far from consensus, view is accepted that the correct valuation methodology to apply to shares in mining companies should be based on option pricing theory then conventional valuation practice of both mining assets and shares in mining companies will need to be fundamentally reassessed.

Jan 1, 1994

Roles of Mineral Impurities and Sulfur in the Leaching Behaviour of Pre-Reduced Ilmenite Ores

Sep 13, 2010

British Coal has always been a big mining company and its management has been beset with many of the problems one would associate with such an undertaking. These include its accountability to Government, its market vulnerability to competing fuels and to imported coal and its relationship with its workforce but also with its own history and size. As a fragmented private industry up to and including the Second World War, it was starved of capital and its management developed an historic relationship with its workforce which was often counter productive to success. Once nationalised, it contributed greatly to post-war industrial regeneration, investment was forthcoming to reconstruct existing mines, sink new ones and to mechanise production operations. British manufacturing companies contributed to this mechanisation drive, the very success of which drove up production and productivity and against a declining market, contributed to the reduction in size of the industry. Production machinery design evolved in the 1960s with close collaboration between manufacturers and users such that an inevitable proliferation of machinery types and specifications developed to meet local needs. Longwall mining internationally outside Western Europe only became significant in the 1970s. It became apparent that international operators demanded higher levels of plant performance from British manufacturers than British Coal did. This was the birth of the "heavy duty" plant concept. As international performances outstripped our own then British Coal moved in to invest in itself, in this heavy duty. This re-investment commenced in the mid 1970s but only gained real momentum in the 1980s when it became a virtual re-equipping exercise for the whole industry.

Jan 1, 1988

By Lumley G. I, Duffy W. J

The risk involved with incorporating new/unfamiliar technology into mines has, in the past, largely been evaluated by the supplier of the technology. The implications on safety and productivity has been accepted as part of the process of `getting up and running'.This has changed. As companies see the lost productivity and accidents actually costing significant dollars, risk assessment is becoming an important part of the implementation of new equipment. Regulatory authorities are also seeing the preventable incidents and in some cases are now requiring a risk assessment to be undertaken on new equipment at a Mine.

Jan 1, 1992

Information obtained from a reconciliation system provides fundamental indicators to an operations performance and is often neglected as a key performance indicator when developing a business plan or mining schedule. The cycle of exploration, ore definition, mining and processing within a company is constantly scrutinised both internally and externally as to the safety, environmental and financial performance of these activities with the operators judged on their performance on a periodic basis. However, it is not unusual for the reconciliation process to be given scant attention until a serious issue (usually a shortfall) occurs, at which point short-term solutions may be implemented which only serve to compound the original problem. A robust reconciliation system takes time to develop and implement initially and must continue to evolve with time. The best systems are those where all the stakeholders in the ultimate outcome are involved in the design and accept responsibility for the validity of their component inputs. Output from the reconciliation process can be utilised to fine-tune all aspects of an operation once the underlying issues leading to a particular result are understood.

Jan 1, 2002