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The mineralogy, textures, and genetic significance of a silver-rich siderite vein and an apparently co-genetic galena vein from the South mine, Broken Hill are discussed.Both veins cut sharply across the Main Lode Horizon and appear to be coeval with thc A.B.H. Consols lode.The minerals of thc siderite vein apparently result from the preferential leaching of silver from Main Lode Horizon ore with a demonstrable "breakdown series" commencing with tetrahedrite, passing through silver sulpho-salts, and ending with simple binary compounds or with elemental silver.The siderite vein has been deposited by metahydrothermal fluids along the lines of Schneiderhohn's "secondary hydrothermal" mineralization.

Jan 1, 1968

CONTENTS: Broken Hill The mixing stations.Operating and mixing apparatus.Pulp distribution.Stope preparation.Filling procedure.Consolidation of old fill.Drainage:Pulp density tests. Life of sand pipe lines.Results.Advantages and disadvantages.Conclusion and acknowledgments.General remarks on South Limited.Mining methods.History of stope filling in Broken Hill.Need for a new and better filling method and transport system.Initial experiments with hydraulic stowing.Source of the sand.Water Supply.Signalling system.GENERAL REMARKS ON BROKEN HILL SOUTH LIMITEDThe South Mine, property of Broken Hill South Limited, is situated at Broken Hill, N.S.W., Australia, towards the southern end of the main lode.The leases (M.L's 7 and 8)' cover a length of 2,400 feet along the lode outcrop and the workings extend, at this date, to a depth of 1,940 feet below the collar of the original main shaft and to 825 feet below sea level.Mining operations have been continuous for about 58 years and during this period nearly 12.5 million tons of ore have been mined. The monthly tonnage extracted approximates 30,000 tons in normal times.The ore is a mixed sulphide containing galena and marmatite; the gangue minerals are principally calcite, rhodonite, quartz and garnet.A typical assay for a monthly period is 14·40/0 Pb., 5·6 ozs. Ag., and 11· 60/0 Zn. The whole of the ore is concentrated on the property by combined gravity and flotation methods. The lead and 'zinc concentrates produced are railed to other centres for the extraction of the contained metals.MINING METHODSMining practice throughout the field varies only in minor details. The ore-bodies forming the Broken Hill Lode lie within complex folds arranged along a shear and vary in size and mineralogical associations, but all the mines have similar types. Some of the ore-bodies have weak walls, but the chief difficulty in mining is caused by "heads" and "flaws" in the ore.Besides these local weak areas there are ground movements-referred to later-of varying magnitude extending throughout the central portion of the lode where the large ore-bodies, several hundred feet wide, approached the surface.

Jan 1, 1944

Jan 1, 2004

By A M. Purba and A Sjadat, A D. Wilson

Ongoing mining of the East Ertsberg Skarn System orebody below the Gunung Bijih Timur and Intermediate Ore Zone caves has been relatively successful and a ramp up to 80 000 t/d was achieved in the Deep Ore Zone Mine. However, the distribution of production, the overall drawpoint availability as well as the rate of change of the cave back profile has not followed the anticipated path. Several key factors influencing cave growth and progress, grade variation, fragmentation, wet muck and surface subsidence have been recognised over the life-of-mine that now have to be taken into account for planning the later stages of mining.The paper will discuss the influence of geological controls of lithology and structure – how this as well as other contributing aspects have impacted ore flow, contributing to some of the widespread panel damage, and been a key factor in compacted draw columns and caused an accelerated appearance of water ingress. This in turn has rapidly changed the distribution of wet drawpoints requiring remote mucking and special controls that also affect the call from the remaining dry drawpoints. Comment is also made on the potential final cave profile if it continues along the current trend and some discussion is offered about possible mitigation measures if this were to come about.CITATION:Wilson, A D, Purba, A M and Sjadat, A, 2016. Progressing cave performance into the later stages of the Deep Ore Zone mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 285–292 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Turker L

The leaching of Tellness (Norway) ilmenite concentrate in hydrochloric acid and mixed aqueous HCl-alcohol solutions at boiling temperatures was investigated. It was found that the alcohols methanol, ethanol and ethylene glycol all substantially increased the leach rate and in the case of methanol and ethanol this was achieved at lower boiling temperatures compared with aqueous HC.

Jan 1, 1986

Traditional in situ fan flow test methods under accepted standards require determinations to be made of both static pressures and total pressures during testing. This is to determine the resultant velocity pressures, which are vital in the accurate determination of the final fan airflow. These crucial velocity pressure (Vp) determinations are normally determined using simple manometric instrumentation such as an electronic manometer or an inclined liquid filled manometer. There is relatively little noise or fluctuation in the static pressure determinations and they can be quite easily and accurately recorded. There is almost always considerable fluctuation in the velocity pressure determinations though due to the highly turbulent and irregular velocity profile normally found in such in situ installations. This velocity turbulence means that the recording of such data is subject to random human error as the observer tries to average such fluctuations mentally during the observation period. Worse than this, and in the extreme, the recording of such velocity pressure data could actually easily be misreported if, for some reason, persons chose to do so.The author has devised a field method using highly accurate quartz crystal logging barometers to objectively record these velocity pressures. The method eliminates the ability to either mistakenly or intentionally misreport these crucial velocity pressures and is carried out in parallel with the recognised methodology, so result comparisons can be drawn. As such, a far greater level of confidence can be achieved in the final flow performance results than using the traditional more subjective method. Further to this it is difficult and almost impossible to refute the results using this ancillary substantiation method.The accurate determination of fan flows due to the impost of the carbon tax has taken on much more significance given the financial impacts in Australia at this time. The methodology detailed herein can be applied equally for both fan flow compliance testing and the verification of mine airflow data for greenhouse gas emission evaluations.The paper utilises the results of one 24-point pitot traverse to demonstrate the various findings. These include the very wide range of velocity pressures, which were logged at most of the measuring stations. It also illustrates how the method is utilised and compares the results derived from both this method and the more subjective traditional method along with the benefits of logging the velocity pressure results during the testing process.CITATION:Rowland, J A, 2013. Removing some subjectivity from traditional BS 848 and ISO 5802 in situ fan flow tests, in Proceedings The Australian Mine Ventilation Conference , pp 155-162 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

A commonplace, sometimes overlooked or taken for granted, article of everyday existence is the tin can. Produced from thin gauge low carbon steel, and commonly coated with a mere 60 millionths of an inch of pure tin, the product is however strong and corrosion resistant. Tin-plate serves a myriad of purposes-the most important being to meet the requirements of the canning industry. Australia's newest steel product, tin-plate, was first produced on a commercial scale during the early part of August, 1957. The commissioning of the Hot Dip Tinning Plant (Fig. 1) of The Broken Hill Proprietary Co. Ltd. at Port Kembla, marked the culmination of a proposal dating back to 1939, the advent of World War II having caused its deferment to the present time.Cornish tin is known to have been exported as early as 300 B.C. to Syria and tinned vessels existed even in the year A.D. 23. The tin coating of plate could be described as an ancient art, believed to have had its origin in Bohemia in the thirteenth century. During the next 450 years, the process spread through Saxony to Pontypool in Monmouthshire, but it was a further half century before any measure of success was obtained.Perhaps the two greatest milestones in tin-plate manufacture were the rolling of iron plates first carried out in 1728, thereby outmoding the hammer formed sheet, and more recently, the development of the electro-deposition process. By the nineteenth century, several important changes had arisen; namely, the substitution of steam for water power, coke for charcoal in the production of the base metal, and...

Jan 1, 1958

At Appin colliery, geological structural analyses and investigations of roof conditions suggest roof failure may be attributed to vectorial stresses acting on underground openings, and inducing movement along inherent discontinuities in the surrounding rocks. Certain complex joint and fracture patterns tend to exhibit the effect of this movement resulting often in local deterioration in natural support.The following conclusions are drawn.1. Roof failure is related to the inherent nature of the roof rocks, the presence of mechanical discontinuities, and the vectorial stresses imposed upon it.2. Roof failure is not necessarily related to the statistically most prominent jointing.3. Colliery development approximately parallel to the direction of the statistically most prominent jointing sometimes results in favourable roof conditions.4. The maximum principal stress is the resultant of those vectorial stresses acting upon a mine opening and may be inferred from roof adjustments to those stresses after mining.5. Statistical analyses of jointing in the mine workings can provide clues to the tectonic force or forces which have been regionally or locally influential.6. There is a probable relationship between mining induced fracturing, jointing, and micro-fractures in quartz grains, within the sediments of the mine roof.

Jan 1, 1970

By A Giblett, S Hart

"In 2015 operations under the ownership and/or management of all Newmont Mining Corporation subsidiaries (Newmont) produced 5.7 Moz of gold and 619 Mlb of copper from mining operations in five countries, with well over 100 Mt of ore processed by various grinding technologies. Processing methods used in the extraction of metals include flotation, oxidation, conventional cyanidation and heap leaching. The grinding technologies applied in milling operations feeding metal recovery processes include conventional wet grinding semi-autogenous grinding (SAG), rod and ball, dry grinding, concentrate regrinding and ultra-fine grinding, and ball milling of high pressure grinding roll product. SAG/ball (SAB) configurations represent the dominant comminution flow sheet within the company and the circuit configurations employed include SAB, SABC-A, SABC-B and single-stage (SS) SAG milling, with SAG mill feed ranging from run-of-mine (ROM) ore through to secondary crusher product. The collective experiences earned from designing, operating and debottlenecking these various comminution circuits provide many lessons that can be applied to the design and optimisation of future operations. This paper provides an overview of Newmont’s diverse comminution circuits, discusses recent performance and offers some insight into optimisation and design considerations based on recent experience in both endeavours.Citation:Giblett, A and Hart, S, 2016. Grinding Circuit Practices at Newmont, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 293–302 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

The Marvel Loch Operations (MLO) plant was treating ores from up to six MLO sources and in addition needed to blend externally sourced ores with its own ores. This presented a metallurgical accounting dilemma, which was subsequently addressed by the design, implementation and testing of an automatic sampling system. The MLO automatic sampler was well designed and has been the subject of previous internal and external reviews. The sampling action is fully automated and the unit is essentially self cleaning particularly when sampling primary ores. The purpose of this paper is to document the rationale behind the design, the specific details of the sampling station, its use for ore purchase purposes and an assessment of the sampling system to meet the needs of the operator.

Mar 1, 2010

THE irregularity of the Mount Morgan ore body presents problems other than those for mining only. For irregularity of outline is coupled with irregularity of grade, and the ore varies so rapidly from profitable to non-profitable, and from highly siliceous to highly pyritic, that the task of estimating quantities and values of ore reserves is manifestly rendered a difficult one, while the actual disposal Of the broken ore demands constant supervision.Four classes of ore are handled. The oxidized ore, cheaply mined and cheaply treated, is obtained by quarrying from the top of the mountain. Below the 315-ft. mine level (measured from the original summit) sulphide ore comes in, and this is divided into siliceous sulphide ore (too siliceous for economic smelting), sulphide ore suitable for smelting, and ore too poor either to be smelted or to be treated by wet process with the siliceous ore. It is with these three latter descriptions of ore that this paper principally deals.Although the output from most stopes in the mine may usually be presumed beforehand to be either smelting or wet-treatment ore...

Jan 1, 1910

By Segnit E. R

Results are reported of a study of the reactions occurringin the combustion of chaIcopyrite particles underconditions simulating those in the shaft of a flashsmelter.The reactions were studied using kinetic and mineralogicaltechniques. Reactions. rates above 500°C wererapid, most of the reaction taking place in less than 50ms. Final products were copper-iron ferrites with spineltype structures. Probable reaction mechanisms are discussed.

Jan 1, 1977

By J Parr, P Ashworth, S Johns, C Yeats, A Littleboy

The ocean floor is increasingly being discussed in terms of its resource potential. New discoveries, improved knowledge and access to unexplored areas of the deep sea and continental shelf are some factors contributing to a renewed interest in the seafloor exploration and mining industry. The industry has been referred to as the ænext minerals frontierÆ. To date, much of the research has focused on proving economic and technical viability of the industry, with environmental issues addressed locally. However, there is limited research internationally, and none known in Australia that considers the social viability of the industry, addressing issues such as regulatory contexts, international precedence and public acceptability. Does the nascent seafloor exploration and mining industry have a social license to operate? Does it have support amongst the wider community? If not, why not? The Wealth from Oceans National Research Flagship explored these questions by scoping the social issues that would surround an expansion. Two desktop studies provide insight into the current level of activity in seafloor exploration and mining, recent developments and the regulatory regimes on which the industry is based. One study focused on the situation in Australia, while the other was internationally focused. A series of workshops were held with key stakeholders from government agencies, industry and other interested parties, such as environmental groups and the fisheries industry. These workshops identified and explored the different stakeholdersÆ perceptions of the benefits, concerns, opportunities and key questions associated with an expansion of the seafloor mining industry. The desktop studies revealed that Australia is one of only a few countries with legislation specific to seafloor exploration and mining. Nevertheless, barriers to licence approval exist because of lack of precedent in applying this legislation. Consequently, the decision process can be vulnerable to political issues and subjective judgements. The outcomes from the stakeholder workshops suggest this inconsistency may be influenced by the high levels of concern and uncertainty over environmental impacts. Uncertainty over environmental impacts can influence the acceptability of an environmental impact assessment (EIA) and also mean the perception of risk is variable. Overall, this research suggests that the future of the seafloor exploration and mining industry will be highly dependent on AustraliaÆs ability to:improve the knowledge-base underpinning the regulatory regime,generate open and transparent communications between stakeholders, andimprove the understanding of policy and regulatory processes.

Jan 1, 2008

By Tumilty JA, Schmidt CG

Sulphide ion is a powerful poison in gold cyanidation, however, the detrimental effect is less severe in plant practice. This is thought to be due to the presence of depassivating elements in the ore, mainly lead. Trace amounts of lead can counteract the poisonous effect of considerable amounts of sulphide. The reaction is instantaneous and is likely to be a direct involvement in the electrochemical surface reaction. Lead addition cannot be regarded as an all-round cure when experiencing poor leach efficiencies. A possible beneficial effect depends on the mineralogy of the ore and has to be determined individually for every material.

Jan 1, 1989

The area around Big Bell was actively explored and sporadically mined for gold from 1904 onwards. The lease was named Big Bell in 1913. The property became established as a major mining centre with the development of the Big Bell underground mine in 1936. Mining operations commenced in late 1937 and ceased in January 1955, after milling 5.56 million tonnes of ore and producing nearly 21 tonnes of gold. In 1969 Australian Consolidated Minerals Ltd (A.C.M.) acquired the deposit then explored it alone and in joint venture until the current joint venture agreement with a subsidiary of Placer Pacific Limited (PPL) was negotiated in 1984. Following exploration and evaluation of near surface mineralisation, and a reassessment of the remnant pillars underground, the concept of a large open pit in conjunction with an underground mine evolved. The feasibility study was completed in October 1987, and the decision to go ahead was formally announced on 2nd December 1987. Placer Dome Technical Services Ltd were contracted to be the Project Managers, commencing construction on site early in January 1988 and handing the plant over to the operators 13 months later. The capital cost of the project at handover was estimated to be $133 million. The operating team commenced pre-production stripping of the open pit on 1st May 1988. By 31st January 1989 almost 16.0 million tonnes had been stripped and 350,000 tonnes of ore stockpiled.

Jan 1, 1989

By C E. J de Ronde, I C. Wright

Oceanic subduction-related volcanic frontal arcs extend over 20 000 km within the western Pacific basin and over 21 500 km worldwide, yet they remain largely unexplored with respect to active seafloor mineralization. Systematic exploration of 26 major submarine volcanoes along ~840 km of the Kermadec arc northeast of New Zealand has documented ten (39 per cent) as being hydrothermally active. This frequency of venting is comparable to that on slow-to-moderate rate spreading mid-ocean ridges, which comprise ~80 per cent of the 60 000 km-long global system of spreading centers. The chemistry of fluids discharged from the Kermadec arc volcanoes is moderated by magmatic components in both the gaseous (CO2 + SO2-H2S) and liquid (Fe) phases at very high concentration.The high frequency of venting coupled with chemically rich discharge discovered during this first systematic survey of any arc system forecasts submarine arcs as being important sources of chemicals to the oceans and as potentially lucrative exploration sites for seafloor mineralization. The exploration protocols developed during these surveys include bathymetric mapping of mostly unknown volcanic edifices, followed by detailed water column profiling and sampling to detect and characterize volcanic fluid emission signatures. These procedures are being refined as the survey progresses, both for efficiency and as direct seafloor observations become available for predictive application of water column plume information to guide seafloor mineral exploration.

Jan 1, 2002

By Beevers J

The Ok Tedi Project is now a high production open-pit porphyry copper mine located in the Star Mountains of Papua New Guinea (PNG). At present, total daily production is 190 000t of ore and waste. Large scale drilling and blasting has only been in operation since 1988, prior to which all material was removed by ripping and dozing. This paper reviews the steps taken over the last 12 months in establishing a more efficient drilling and blasting operation and highlights the significant reduction in powder factor. These improvements have been achieved largely through the introduction of air-bags, controlled pattern expansion and an overall focusing on the operation by involving consultants, ICI's technical service and internal departments.

Jan 1, 1991

New Developments in Spirals and Spiral Plant Operations Records indicate that spiral separators have been utilised in mineral separation for over 100 years. The Spiral's predecessor, the sluice, has been in use for centuries in different forms and a spiral can be thought of as a sluice wound around a column. The spiral separator is distinguished from the straight sluice, and other flowing film separators, in uniquely introducing centrifugal motion. The elegance of the spiral concept was embraced due to significantly improved separation efficiencies, ease of operation and tolerance of variation in feed conditions. Advances in spiral technology have improved the metallurgical performance, modernised the materials of construction, increased unit capacities and simplified operation. These advances have ensured that spirals continue to play a major industry role amidst other advancing and competing technologies. Recent developments in spiral and spiral plant technology include: the launch of the VHG spiral model, specifically aimed at feeds with very high levels of high-density mineral particles; the introduction of a high capacity wash water spiral model; and innovations in feed stabilisation and control. Details of these developments are presented together with the resultant operational benefits including feed stabilisation, product control and improved metallurgical performances.

Sep 13, 2010

By Clements R. J, Davey J. M

Development of the process from the pilot stage to the current operation of the Capel, WA plant is briefly described.The design criteria for a larger sized plant are discussed together with factors that relate suitable feedstocks and coal types to the capital cost, capacity and product grade of future plants at locations other than Capel. The application of the process to the direct reduction of iron ores is briefly discussed including its commercial application at Rockwood, Tennessee.

Jan 1, 1980

By Met M, Orr C. W, Met B. E

As was mentioned in the last paper of this series(l), magnesium was added to lead with the idea that it would act as a de-oxidiser. The magnesium lead alloys give rise to an inter-metallic compound of the composition Mg2Pb(2) and it has some remarkable properties. It is known to disintegrate on standing in the atmosphere and it confers this property also on lead alloys in which it occurs. Magnesium forms a solid'solution with lead, and according to Kurnakow, Pogodin' and Vidusova(S) the limits of solubility are as follow...In conformity with the practice used in preceding series, the limit of concentration used in the present investigation was 0.1 %. Accordingly, it would be expected that all the alloys used would consist of the solid solution and the detrimental Mg2Pb would be absent. Whilst this was the case, it...

Jan 1, 1939