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By G D. Price

The Golden Blocks Goldfield is located in the Slaty Creek area,North West Nelson, about 20 km west of Collingwood. Alluvial gold was discovered in Slaty Creek in 1861. Gold was mined from quartz veins up to 1.5 m thick at nine mines from the 1890s until the closure of the Aorangi Mine in 1911. Total production from the Golden Blocks Goldfield is estimated at 46 000 ounces of gold. The Aorangi Mine was the largest mine, with a recorded production of 27 978 ounces of gold at an average grade of 36 g/t. Quartz veins containing gold and sparse sulphide mineralisation occur in a slightly metamorphosed, complexly deformed over-turned sequence of Lower Ordovician sandstones and shales. Primary gold mineralisation is associated with intensely deformed zones that occur near or at carbonaceous shale and sandstone contacts. Some eighty-five percent of all gold production (39 000 ounces) came from four mines confined to the stratigraphically lowest, most widespread shale unit. The quartz veins exhibit textures consistent with a hydraulic fracturing mode of vein formation with fissure infill vein types predominating over replacement textures. Stylolites of carbonaceous material and recrystallization features within the veins suggest multiple phases of deformation. The lack of wall rock alteration, and low primary fluid inclusion temperatures of 200¦ - 265¦ indicate that the ore fluids were associated with a low temperature epithermal system. A model consistent with similar mineralisation styles observed in Ordovician sediments from Pacific Rim occurrences is presented. The high grades (up to 100 g/t) mined from the upper levels of several mines suggests supergene enrichment processes associated with the Upper Cretaceous weathering surface. The Golden Blocks Goldfield has had no modern exploration. The most recent exploration was undertaken in the early 1980s. There are known acid intrusives in the area, with potential for the application of new models of intrusive-related gold mineralisation.

Jan 1, 2004

By T Huynh, V Matanitobua, J Zheng, B N. Noller, J C. Ng, H H. Harris

A risk assessment was undertaken of the aquatic ecosystem and bioaccumulation of metals and metalloids in fish at the Leichhardt River, Mount Isa, Queensland. Residual contamination of metals and metalloids in Leichhardt River sediment was assessed and arose from mine practices using river discharge in the 1940s. The ecological risk assessment of sediments involved comparison of the concentrations of heavy metals and arsenic with those of the ANZECC/ARMCANZ (2000) Interim Sediment Quality Guidelines (ISQG). Results indicated that all sites including the background site exceeded one or both the ISQG-high and ISQG-low trigger values based on total concentrations. A lesser number of sites exceeded the ISQG-low trigger values following the 1 M hydrochloric acid extract step, which was used as an indication of bioavailability. An additional risk from particulate matter in river sediment is that acute human toxicity from the consumption of fish contaminated with metals and metalloids is unlikely. The potential risk was assessed by comparing with the maximum levels set by FSANZ (2010) for fish consumption by children and adults. In general, the liver of the fish have higher heavy metal and metalloid concentrations compared to the muscle. Frequent or regular consumption of fish from the Leichhardt River that exceed maximum levels (ML) of heavy metals and metalloids is not recommended. Risk analysis showed that an adult can consume up to 5 kg of fish fillets every day from fish caught at the man-made Lake Moondarra downstream on Leichhardt River and still be within safe consumption levels whilst a child can eat up to 1 kg daily.CITATION:Noller, B N, Ng, J C, Matanitobua, V, Harris, H H, Zheng, J and Huynh, T, ?2014. Assessment of ecotoxicology and health risk from bioaccumulation in fish of heavy metals and metalloids from historical mine practices in the Leichhardt River, Queensland, Australia, in Proceedings Life-of-Mine 2014 , pp 337–348 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By Scott IA, Jefferson C, Dipasquale S

This paper describes the use of modelling and simulation techniques in the analysis of the heavy medium plant at the Lead/Zinc Concentrator of Mount Isa Mines Limited. The objective of the study is to determine how to increase heavy medium plant recovery at a higher than current rejection rate in order to achieve the desired throughput through the grinding and flotation sections of the concentrator. Three options were considered: 1. Install smaller aperture preparation on screen to enable the cyclones to be fed finer materials. Install smaller diameter cyclones. 3. Maintain low viscosity medium.

Jan 1, 1987

It is my role at this juncture to report to you on behalf of the Council of Mining and Metallurgical Institutions itself. In essence, the Council is an orbital body - a little like Halley's Comet - it returns to earth, in spectacular style, once in every four years. We must acknowledge, however, that the spectacle is provided by the constituent member body organising the particular event and, on this occasion, it is The Australasian Institute of Mining and Metallurgy. On behalf of the Council and its other constituent bodies may I thank the Australasian Institute most sincerely. Our thanks go to Sir James Foots, the President of the 13th Congress, and to all the members of the organising committee and to the five sub- committees. Over 40 people are involved as full members and I am certain there will have been many more involved in very meaningful ways. None of this great- team would ask me to mention them individually, I'm sure, but to fail to acknowledge the role of John Funnell, the Honorary Secretary, would be an unforgivable omission. We must also thank the kindred institutions in Japan, Korea, Thailand, Malaysia, and Indonesia who all helped with the tours themselves or with the initial preparations. Qantas, Jetabout Australia, and Jetabout Singapore have all also made very important contributions and, in our different ways, we each owe our thanks to them. At the two most recent meetings of the Congress - in Hong Kong and Johannesburg - Professor Marston Fleming made this report on behalf of the Council and was supported on both occasions by Robert MacWilliam as vice- chairman. Marston died in 1983 and Robert died in 1984; both men contributed a great deal to CMMI and we will miss their counsel for a long time. As you know, Sir Alistair Frame succeeded Marston Fleming as chairman in 1984 and I succeeded Robert MacWilliam as Vice-chairman.

Jan 1, 1986

By Todd W, Stone C

A 3D graphics modelling system has been applied to longhole stope ring design at Z.C. Mines, Broken Hill, NSW. This has been in operation for a four month period (January, 1988). The purpose of this application was to provide computer assistance to mine planning engineers and blasthole design draftsmen for the longhole design process, particularly by: 1. reducing the- volume of tracing, drafting and geometric manipulation which is a significant feature of the manual design process, 2. providing additional design drawings to enhance the conception and implementation of stoping design.

Jan 1, 1988

By Woodlands W. K

A 3D graphics modelling system has been applied to longhole stope ring design at Z.C. Mines, Broken Hill, NSW. This has been in operation for a four month period (January, 1988). The purpose of this application was to provide computer assistance to mine planning engineers and blasthole design draftsmen for the longhole design process, particularly by: 1. reducing the- volume of tracing, drafting and geometric manipulation which is a significant feature of the manual design process, 2. providing additional design drawings to enhance the conception and implementation of stoping design.

Jan 1, 1988

By Groudeva VI

The biohydrometallurgy of gold is based on different processes which could be grouped into four main groups (Attia, Litchfield and Vaaler, 1985; Karavaiko et al, 1988; Groudev, 1990): 1. bacterial oxidation of gold-bearing sulphide minerals by chemolithotrophic bacteria to facilitate the subsequent chemical extraction of gold; 2. solubilisation of gold from oxide ores by means of heterotrophic bacteria; 3. recovery of gold from solutions by biosorption; and 4. microbial modifications of the surface of gold-bearing sulphide minerals to improve the subsequent gold concentration by physical dressing methods (eg flotation, oil agglomeration).

Jan 1, 1993

Distal air-fall ashes are widespread deposits that may record volcanism many hundreds of kilometres from their source. They are characteristically thin, fine-grained and have a low preservation potential usually being either eroded, or reworked and incorporated in overlying sediments following deposition. The most likely sites of accumulation are deep sea, lake and swamp environments where low energy conditions favour preservation. Post-depositional alteration of predominantly glassy volcanic ash is commonly extensive hampering identification of such layers in the geological record. As a result air-fall tuffs are poorly represented in the rock record and furthermore are commonly misinterpreted. Southeast Queensland during the late Triassic hosted active silicic volcanism and a number of fault-controlled basins in which coal-bearing sediments were accumulating. Silicic volcanics of late Triassic age are represented by the Brisbane Tuff in the Brisbane city area, the Chillingham Volcanics to the south of Brisbane and extending into New South Wales, the North Arm and Mount Byron Volcanics to the north of Brisbane, the Aranbanga Beds exposed around Gayndah and the Agnes Waters and Muncon Volcanics which occur northwest of Bundaberg. Stephens (1986) interprets these Volcanics as the remnants of a major silicic igneous 'province which he likens to modern continental orogenic margins. The Ipswich, Tarong and Callide Basins of southeast Queensland all contain coal measure sequences of late Triassic age that accumulated in alluvial plain environments. A Dicroidium flora is common to all and palynol.ogical evidence indicates a late Triassic (Carnian) age (de Jersey, 1975; Stevens, 1981). The coal seams of the three basins are characterised by their thickness (up to 25 m) and the presence of abundant thin, laterally persistent, kaolinite claystones (tonsteins) that show a marked similarity of morphology, texture and mineralogy. Detailed studies of the Ipswich Coal Measures (Falkner, 1986) suggest a volcanic air-fall origin for the tonsteins of the Ipswich Basin. Similar.tonsteins from the Tarong and Callide Basins provide evidence for widespread silicic volcanism during the late Triassic in southeast Queensland.

Jan 1, 1987

By Brimblecombe P

Morwell Open Cut is a continuous mining operation employing 5 buck- etwheel excavators, I bucket chain excavator and 54 conveyors. The combined bunkering capacity at both client Power Stations represents less than 12 hours maximum coal demand. This creates an extremely dynamic operating environment, which is further complicated with significant variations in both excavating and transportation plant capabilities. To achieve set objectives, including- I adequate reserves, 2 coal supply reliability, 3 cyclic plant maintenance, 4 minimal cost of coal, scheduling of the operation requires constant monitoring and reappraisal.

Jan 1, 1989

By M Heidari, M Ataei

Today, the selection of a mining method is a multi-criteria decisionmaking process, with many factors in this process connected to each other. These trends do not have a high degree of confidence. In this study the analytical hierarchy process was used to select the suitable mining method for anomaly No 3 of Gol-Gohar iron mine of Iran. The results of this study show that gathering all existing information from the exploration stages and using AHP technique, the open pit mining method is the mining method for this anomaly.

Jan 1, 2003

By Smitham J. B, Keast-Jones R

Six Australian coals were selected to determine their potential to produce, ultra low ash (less than 2 per cent) coal by progressive size reduction followed by density separation and/or froth flotation. Density separation in organic liquids is effective in the absence of contaminating liberated mineral matter which can be removed by froth flotation with several cleaning stages. The limit of cleaning of these coals was an ash value of 1 per cent while commercially attractive yields were obtained at 2 - 3 per cent ash depending on the coal.

Jan 1, 1987

By T Alexieva

Since the early 1900s the geotechnical community has investigated every significant failure of a tailings dam, improved our knowledge of the behaviour of the tailings storage facilities, developed analysis methods, compiled lessons learned, and committed to zero failures. The rate of occurrence of tailings dam failures has reduced since the 1980s, however, failures continue to occur and continue to surprise us. At BHP, we have decided to take an approach to the tailings management that is similar to the approach to safety. We are looking at ways to eliminate, substitute, separate or engineer around the hazard (tailings dam failure). As such, our ultimate long term goal would be to eliminate the need for new tailings facilities. Unfortunately, we have not developed yet technologies for extracting many of the common metals and minerals without producing tailings. Our shorter term goal is to substitute the current conventional slurry tailings facilities with less risky dryer facilities. We are working with vendors and research organizations to develop technologies that can be efficiently applied on a large scale. At the same time, we are committed to using the best available engineering to reduce the risks associated with our existing and new conventional tailings facilities. The best engineering can be achieved by people with the appropriate education, experience, attention to detail, discipline and authority. We have implemented a system of governance to make sure, we have the best engineering applied to all our facilities, considering the specific conditions at each site.This paper presents the current tailings governance process at BHP, and the initiatives that were undertook towards achieving a zero failure goal. CITATION:Alexieva, T, 2018. Tailings governance, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 2–7 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

A minimum target of economic growth in Australia has been set at 5% per annum growth in G.N.P. at constant prices (Vernon Committee). 2. The core of the problem of sustaining steady growth at this or a similar rate is to ensure regular flows of investment. This sustains productivity, helps to control balance of payments pressures, and to check inflation. 3. The regular intake of human and physical resources, in conjunction with intensive capital development involving finance, technology and management, is basic to sustaining the growth rate and ensuring rising standards of living.

Jan 1, 1971

By S H. Begg

"*This is an abstract only*Most technical and economic analyses are performed to reduce uncertainty to help make decisions. Decision-making is about ranking alternatives - rarely are precise predictions required, if even possible. This simple observation has profound implications for modelling approaches, how they deal with uncertainty and the reliability of information provided by subject matter experts.CITATION:Begg, S H, 2013. Some reflections on uncertainty, decisions, models and people, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013, pp 3-6 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 29, 2013

The development of Mount Isa Mines Limited power supply is traced through the history of the mine operations. As would be expected, growth of the power supply system follows closely the increase in mine output, although it will be seen that total kWh. produced per ton milled shows a considerable reduction in later years when the mine output showed a more rapid rate of increase. That this reduction is not more marked is possibly due to the increased community and Shire Council power usage per head of population.INTRODUCTIONThe geographical position of Mount lsa, far from any large regional power supply Authority, dictated the policy that the Company be responsible for the production and suppiy of all power required for the plant operation. The Company also, in November 1937, accepted responsibility for the supply of a part of the power requirements of the township of Mount Isa. The history of power supply to the Mine may be divided into several phases.1. The supply Of lighting and power during the first plant construction period 1929-1931.2. The construction of the first section of the Mines Power Station, comprising Nos. 1 and 2 turbo alternators and boilers.3. The addition of No. 3 turbo alternator and boiler.4. The addition of No. 4 turbo alternator and boiler.5. The addition of No. 5 boiler.6. The addition of a. 2 turbo blowers for air supply to the Copper Smelter converters; b. 1 turbo blower for air supply to the L.ead Smelter; c. 2 turbo compressors for compressed air supply to the Mine and surface plant.

Jan 1, 1961

The common notion that the Box Hole Bore mineralization represents a variant of the Mississippi Valley type, has not been supported by the present investigation. Most of the common characteristics of Mississippi Valley type, namely 1. saturated saline brines; 2. low temperature domain; 3. mineralization in intraformational breccias and collapsed anticlinal structures; 4. hydrocarbon-rich or foetid carbonates, and 5. very simple geochemistry seem not to be applicable. The Box Hole Bore mineralization features: 1. moderately saline brines (18% NaCl); 2. very high temperature (495¦-520¦C) and low density brines, of critical vapour:water ratio and low pressure of formation (700 bars); 3. mineralization confined by faults and ex- tending laterally into carbonates of high pore volume such as stromatolitic dolo- mites; 4. ore environment characterized by oxidizing conditions, such as ferruginous carbonate and silica sands of high energy environment (heavy mineral banding) and 5. more complex geochemistry than is normal for Mississippi Valley type deposits (copper sulphosalts, and appreciable silver content). Additionally, the ore has un- usual textures formed by the replacement of carbonates and barite by large idiomorphic galena crystals. The pressure and temperature domains of the Box Hole Bore mineralization indicate post- Devonian emplacement and local high heat flow, possibly related to the Alice Springs Orogeny. Because of high lead and zinc trace element con- tents (100-600 ppm) of the carbonates, even out- side mineralized areas, it is possible that the mineralizing fluids have derived their metal con- tent from a local source, possibly aided by evap- oritic concentrations of the tidal to supratidal sequences. The new model for Box Hole Bore gives treater importance to the confining faults.

Jan 1, 1984

By T J. Howard

At BHP Billiton Iron Ore operations, run of mine ore from the several Newman Joint Venture (NJV) mines is railed in 12 kt rakes to Port Hedland. Rakes are processed sequentially, with the lump and fines components from each rake sampled after crushing and screening. The grade of ore from the individual mines varies around consistently different means. Although a discrete sample is attributed to each rake, the sample contains some material from the following and/or the preceding rakes due to dilution by ore from the neighbouring rakes during the dumping, screening and crushing processes. Individual rake grades at the port are therefore biased according to the mine sources of adjacently processed rakes. Dilution does not affect the grade of the overall NJV product or the accuracy of port stockpile grades; however, it does limit the ability to use port rake grades to review the quality performance of individual mines and provide meaningful lump-fines algorithms and port to mine biases for individual mines, information that is useful when scheduling ore for mining. A non-linear regression model has been used to estimate the average dilution from the preceding and following rakes. It has been shown that the lump and fines samples for 12 kt rakes are each diluted within the Port process with about 8.3 per cent of the sample coming from the preceding rake and about 3.6 per cent from the following rake. This can bias the reported rake grade by up to one per cent iron. The results of this analysis have been incorporated into the daily grade scheduling system to provide more accurate individual mine grade data and consequently better decision making.

Jan 1, 2007

By Field R. V, Graieg O, George T. J

The design, construction and operation ofa laboratory scale rotary pot kiln are outlined. Charges ofup to 3 kg can be heated to temperatures up to 1200°C in a controlled atmosphere. Some examples of pyrometallurgical investigations carried out using the kiln are briefly described, including thermal reactivation ofcarbon using steam at 550-850°C, high temperature testing ofkiln liners for corrosion resistance to fluoride, and calcination oflimestone. Results obtained from these trials allow either direct scale-up to the Engineering Chemistry Laboratory's pilot-scale (50-100 kg/hr) rotary kiln or modifications to be made to commercial scale processes and/or equipment.

Jan 1, 1986

Under South Africanncoalmining conditions, in the majority of instances coal is won using the bord and pillar system without pillar extraction. Examples demonstrate that strata control policy has an effect on practically all aspects of mining: (1) the choice of mining method; ((2) degree of coal recovery; (3) effect on productivity; (L}.) integration of'-support techniques with other operations. This is confirmed by use of modern research results and computer simulation. Although the examples are drawn from South African experience, the conclusion is generally valid. Strata control problems cannot be solved in isolation but as an. integral part of overall mining policy.

Jan 1, 1971

In any open pit mine some slope instability may be expected. This can range from small scale sliding on individual benches to large scale overall slope failure. This paper presents two case histories which illustrate how mining has successfully continued despite major pit instability. The common threads in each of these are listed below. 1. The recognition of the type and nature of movement (either regressive or progressive). 2. The successful application of simple monitoring techniques to minimise the potential impact on the mining operation, and 3. The management of the waste and ore excavation to avoid potentially damaging and costly situations.

Jan 1, 1986