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Three main divisions of the. Proterozoic are recognised in the North- West of Western Australia. These are referred to, in order of decreasing age as the Mt. Bruce Supergroup, the Bresnahan Group and the Bangemall Group. The stratigraphy and distribution of each is described, their relative ages discussed and a brief geological history of the whole area is Presented.

Jan 1, 1964

Some of the major factors affecting ore reserve estimation in gold mines are discussed together with their impact on computational methods.The major priority in ore reserve estimation is to get sampling and geological problems resolved. Poor basic information cannot be remedied by mathematical methods.Generally the more complex a deposit becomes the greater the need for subjective assessment and the less applicable are more complex ore reserve methodologies.

Jan 1, 1984

By D I. Cliff, K Johnstone, N LaBranche

The resurgence of silicosis and coal worker’s pneumoconiosis (CWP) in mining and the recent ban of engineered stone products underscore the need to comprehensively address mineral dust exposures and the associated health hazards. Worker exposure to particulate matter, remains a pressing concern demanding nuanced exploration as all dusts are not created equal. The established link between silica and respiratory diseases necessitates a more detailed understanding of the characterisation of particulates and their health impacts. While current monitoring relies on total mass, it is increasingly evident that the size, shape, mineralogy and agglomeration of particles play a crucial role in determining health impacts. This has been evident in the engineered stone industry with workers not only facing a greater risk of silicosis, but also seeing a faster progression of the disease and a higher likelihood of dying from it. Simultaneously, the surging demand for critical minerals, integral to low-carbon economies, has seen government and industry fast tracking the exploration, mining and processing of these commodities. Critical minerals, crucial in technologies like lithium-ion batteries and high-performance alloys, are central to achieving global environmental goals. Significant funding is currently being allocated to advance the development and processing of these materials, however there remains a considerable gap in understanding potential health risks, urging comprehensive health risk assessments. To tackle these challenges, the University of Queensland has developed innovative dust characterisation methodologies, including the use of the Mineral Liberation Analyser (MLA), a scanning electron microscope, to characterise respirable and inhalable dust samples. This advanced technique, initially applied in coal and metals mining, is expanding to critical minerals mining, unravelling diverse mineralogical components and particle size distributions. This conference presentation will showcase the latest research, emphasising the use of advanced analytical techniques to deepen our understanding of the size, shape and mineralogical composition of particulate matter. By synergising insights from coalmines, metals mines, smelters, engineered stone and critical minerals assessments, we aim to proactively manage health risks, contributing to safer workplaces and responsible production practices in the mining sector.

Apr 16, 2024

The process and control technologies incorporated into the coal preparation plant at Newlands were to be used for the first time in Australia. The commissioning organisation and procedures were set up on the basis that commissioning personnel, while being competent, would be unfamiliar with the equipment. In addition the commissioning process would have to be completed quickly. The organisation coped with all of these problems and more.

Jan 1, 1986

By Tomlinson R. C

The paper will briefly describe planning in the National Coal Board (NCB) and the contribution that operational research makes to it. It will then give details of some of the models in use and will finally consider critically the problems of looking ahead to the next century.

Jan 1, 1977

By Di Pasquale S, Osler GD

Mount Isa Mines Limited recently commiss ioned an 800 tph Heavy Medium Preconcentration Plant for lead/zinc/silver ores. The decision to build this plant was made in late 1979 based largely on investigations conducted in the Company's pilot plant on a variety of ore types including Hilton ores, between 1972 and 1978. The paper reviews the historical develop- ment of the pilot plant heavy medium circuit through this period and illustrates the extent to which this work impacted on the final design criteria. This review also includes a description of plant operation, manning levels, process equipment and metallurgical performance Achieved.

Jan 1, 1978

By Sandy W

This paper examines the effects of a significant number of plant alterations and modifications to the lead flotation circuit during the past five years. Metallurgical effort is directed largely at the flotation performance of middling streams and current strategies are discussed. The automatic control of cell destination and collector additions are outlined in the latter section of the paper, along with a description of control hardware in current use.

Jan 1, 1983

By S Brochot

In cases where coarse gold is present in a deposit, it is usual to use the screen fire assay (SFA) method to analyse the samples. There is no doubt that this method is more accurate than the standard fire assay (FA) and reduces the risk to have a systematic bias. Nevertheless, the difference between the analytical errors of both methods can be glossed over when the overall sampling error is added to obtain the measurement error. In that case, the advantage of the SFA cannot justify its higher cost.The current paper attempts to address this question in the case of a gold ore deposit with visible coarse gold in various sampling situations (drill core sampling in exploration, blasthole or chip sampling in mining exploitation). The overall measurement error is estimated taking into account the analytical error and all the sampling error components following the Pierre GyÆs theory of sampling.Firstly, only the last sampling stage is considered when the pulverised sample is processed either to obtain one analysis sample for a FA or to be screened and subsampled for a SFA. The calculated measurement error clearly shows the advantage of the SFA specifically in presence of coarse gold. Secondly, the half core sampling is studied to explain the observed discrepancies when controlling the second half core. Finally, the blasthole sampling is treated using in situ heterogeneity models to show that the relative advantage of the SFA is hidden by the large overall sampling error.In conclusion, the choice of the assaying method is discussed at the light of the overall measurement error and in accordance to the analysis objective.CITATION:Brochot, S, 2012. Standard fire assay or screen fire assay? Application of the overall measurement error approach to choose the most appropriate method, in Proceedings Sampling 2012 , pp 135-142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By K H. Esbensen

During the next five years Denmark will implement a significant reduction in the national CO2 emissions to fulfil the Kyoto Protocol. The energy sector is central for achieving this goal and extensive use of renewable energy is the most important single factor contributing to reduce emissions of greenhouse gases. DenmarkÆs renewable energy sources comprise wind energy and biomass. Wood chips and straw are the dominant type of biomass in Denmark. More than 500 000 tons of wood chips are used annually, currently with rapidly growth prospects. This contribution focuses on sampling of wood chips.

Jan 1, 2005

The published safety policy of Mount Isa Mines Limited, together with details of the organisation and control techniques adopted by management to pursue an active safety programme within the company, is presented. The importance of communication by management through the organisational hierarchy and procedures instituted to ensure rapid and concise feedback on safety concerns are detailed. The paper also describes the role of the occupational health department and safety committees in assisting management to monitor the safety effort of supervisors and employees. Current safety performance levels are tabled together with details of some aspects of the programme on which safety effort will be concentrated in the future.

Jan 1, 1975

A proved routine mapping practice is described involving detailed observations on grade and structure. The equipment and methods employed are giving good service under the conditions encountered. Stopes are mapped on every floor whether timbered or open, "Kodatrace" workplans and sections being used, and in addition all development whether in country or lode is mapped.INTRODUCTIONThe accumulation of geological data for application to current mining problems and to the search for new ore involves the necessity for close mapping of all available underground faces and backs. The technique which has been developed to suit conditions at the North and British mines of North Broken Hill Limited forms the subject of...

Jan 1, 1940

Over a four year period from 1984 to 1987, a broad range of ground conditions were experienced in recovering old workings at the Walhalla mine in central-eastern Victoria. Access to the ore zone was gained via old workings and new development. The work included: Recovery of vertical and inclined shafts. Recovery of collapsed winzes. Recovery of level drives and crosscuts. Spiling through broken ground and old mullock. Pre-grouting of caved zones. New development using small-scale rail equipment and "bobcat" Loaders.

Jan 1, 1988

The Broken Hill (BH) Block contains a wide variety of mineralization, with comrodities including Pb, Ag, Zn, W, Cu, Co and Sn. Much of the mineralization is stratigraphically controlled. Fe, Cu and Co-rich mineralization is dcminant in the Thackaringa Group; Pb, Ag, Zn and W is dcminant in the BH Group and Sn mineralization is present above the BH Group. Some mineralization occurs as concordant syngenetic deposits, but other types have been partly or completely remobilized by metamorphism, magmatic activity or hydrothermal fluids. Almost all of the non-syngenetic mineralization, including stratabound, vein and intrusive-related types, has formed from the "recycling" (remobilization and redeposition) of metals originally deposited with the sediments and volcanics of the Willyama Supergroup.

Jan 1, 1983

During the post war era, the requirements of the "Third" World for modern civil works, energy and industry, coupled with an insistence that these capital installations are understood and controlled by indigenous people, have crea- ted a demand and flow of technology from those countries with well developed skills. Thus has grown a real trade in technology - an activity in which consultants play an important role. An indication of the magnitude of this trade is given, together with an outline of some of the special problems. Australia is shown to be dis- advantaged and has been slow to offer the incen- tives to consultants which other countries offer.

Jan 1, 1975

By M J. Cole, J Zhou, D J. Borrow, S M. Iveson, K P. Galvin, J L. Sutherland

New technologies can easily take around ten years to commercialise. Strong research support is needed in parallel with the process of innovation and commercialisation, in building a deeper understanding of the underpinning physicochemical and hydrodynamic forces that deliver the separations, in achieving improvements, in the deployment of a new technology, and in expanding the innovation platform to create new IP. External investment beyond the research, derived from the genuine value proposition of transformational change, funds the pathway for traversing the so-called Valley of Death.

Aug 24, 2022

A very sensitive high-speed two-colour pyrometer was built to measure the temperature of single particles of sulphide mineral, typi- cally 50 pm in diameter, as they burnt while entrained in a hot gas stream. The pyrometer has been used to study the burning of pyrite and chalcopyrite particles and has thrown light on cenosphere formation. Measured maxi- mum temperatures have been compared with values predicted by diffusion-based models. The pyrometer has also been used to study the burning of small captive pellets (2-9 mmm dia- meter) of lead-zinc concentrate.

Jan 1, 1984

By Sneyd R. J, Walton M. C

In early 1987 Minproc acquired a license from the inventor to engineer and construct acid plants incorporating the Fattinger technology. The process offers a simple and reliable method of producing sulphuric acid from metallurgical off gases at significantly lower capital and operating costs than the more familiar contact process. The process also offers the simultaneous production of nitric acid, if the NOx content of the off gases is high enough. A development of this latter process has other applications within the minerals industry, particularly in conjunction with refractory gold ore preoxidation.

Jan 1, 1989

In recent years the use of directional drilling has become increasingly popular in several applications. These include shaft pilot holes, exploration drilling, mine service holes and drilling beneath surface structures and obstacles. The prime objectives are to increase accuracy and reduce time, cost and environmental disturbance.

Jan 1, 1992

By Waldram JT

The Kelsey Centrifugal Jig incorpo- rates the principles of operation of a conventional mineral jig, at the same time utilising high centrifugal forces to extend concentration to very fine heavy minerals. The main operating variables which are adjusted to control processing of different types of material are centrifugal force, ragging material and size distribution. Pilot plant trials have been under- taken to examine concentration of a mineral sand in which the heavy mineral particles occur mainly in the minus 0.075 plus 0.032 mm size range. Stage recoveries of greater than 90% were achieved at concentration factors of up to 2, although lower recoveries were obtained with higher concentration factors. A final concentrate containing 65% heavy minerals was obtained.

Jan 1, 1986

Mr. Bradford said: - On assuming this chair, which has been oc- cupied by so many gentlemen of conspicuous ability, my first words must be an expression of the gratitude I feel for the honour you have done me in electing me to be your President for this year. When considering the subject matter of this address to you to- night, quite frankly may it be stated that for a long time I was on the horns of a very great dilemma, for while I could discourse on the modern political trend in relation to our industries at great length, it appeared to me that this was not the place for such a discussion.

Jan 1, 1987