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The introduction of a new mining method to Australia is not without its risks and challenges. This paper discusses the processes of planning a new operation, with particular emphasis on block caving and its Northparkes adaptation. As well as applying advanced technologies, here also is the opportunity to develop the art and science of block caving for its application to a wider range of geotechnical conditions than previously Envisaged.

Jan 1, 1995

By Jephcott S

The McArthur lead-zinc-silver deposit is of the stratiform type. It consists of a mineralized bituminous shale sequence containing some tuffites, numerous graded beds and isolated slump breccia horizons. The principal sulphides; pyrite, sphalerite and galena, are essentially restricted to the shales and the genetically unrelated turbidites contain only minor mineralization. The geochemistry of the deposit has been investigated with respect to the stratigraphio column and mineralogy of the sediments.

Jan 1, 1980

By G Malherbe, J Gonzalez, D C. Franklin, J Bassan, C T. Farrelly

To respond to ever-increasing challenges, mining companies have been experimenting with new business models and technologies in order to speed mine development, production, processing and transport. The various experiments involve mobile access to data, intelligent sensors, advanced analytics, virtual collaboration, virtual reality, automated equipment, remote operations centres and strategic partnerships. A synthesis of all these components creates a ænetwork effectÆ that can dramatically improve the overall effectiveness the entire operation. The concept of the Network Centric Mine borrows from a variety of industries, including defence, aerospace, aviation, petroleum, utilities and manufacturing. Central to the concept are improvements to the way we connect people, process, information and technology, resulting in a more highly collaborative business model, with roles and processes designed to take advantage of new technology. The components of the mining operation act as a connected network aimed at a common goal, regardless of the boundaries of organisation and location.The design of this new organisational ecosystem needs to take into account the recent advances that enable the æplug and playÆ integrated collaborative environment, including cloud computing, mobile devices and social networking, as well as advances in augmented reality, robotics, geo-location, digital labelling, simulation and analytics. However, the most consistent lesson from other industries is the need to properly enable the behaviour and process changes necessary for success.Benefits from adopting a network centric approach include the more effective use of scarce expertise, improved data and information analysis, reduced process variance, and more informed and faster decision-making. The future of mining will see more technology savvy workers who will drive the adoption of new processes. The operations will shift from a relatively static and disparate set of functions, to a digitally aware, dynamic, automated, integrated and interactive environment, with increased agility, lower operating costs, higher productivity and improved safety.CITATION:Farrelly, C T, Malherbe, G, Gonzalez, J, Bassan, J and Franklin, D C, 2012. The network centric mine, in Proceedings International Mine Management 2012, pp 143-160 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By B Rohrlach, J Gonzalez, A Buenavista

Located on the island of Mindanao in the Southern Philippines, the Tampakan copper-gold deposit represents a major high-sulfidation epithermal deposit superimposed on an underlying porphyry copper system. With a recent JORC compliant indicated and inferred resource estimate of 1104 million tonnes at 0.65 per cent copper and 0.26 g/t gold at a 0.3 per cent copper cut-off grade, Tampakan represents the largest undeveloped copper-gold deposit in Southeast Asia. Since its acquisition by Indophil ResourcesÆ affiliate Sagittarius Mines Inc in August 2002, the deposit is the subject of an ongoing preliminary feasibility study into project viability that is initially focused on a higher-grade copper zone in the north-central part of the deposit. The deposit is hosted by a sequence of subaerial andesitic flows (Tampakan Andesite Sequence) related to a highly eroded andesitic stratavolcanic complex of Pliocene age. Detailed mapping and geochronological dating has identified four volcanic cycles or centres that have been sequentially developed and eroded. This stratovolcanic complex is interpreted to lie on the northern extension of the Sangihe volcanic arc that extends from Northern Sulawesi in Indonesia. The Tampakan district is located within a complex tectonic setting dominated by WNW trending wrench faults that form part of the trans-Mindanao Cotabato Fault Zone. The Tampakan deposit is located near the intersection of one of several WNW trending splay structures with a prominent NNE trending dilational structure, one of many that transect the host volcanic complex. High-sulfidation style copper-gold mineralisation at Tampakan is broadly associated with and central to a flat-lying tabular body of pervasive silica and silica-clay alteration developed within a district- scale lithocap of advanced-argillic and argillic hydrothermal alteration that extends over an area of 90 km2 within the volcanic complex.

Jan 1, 2004

By R Moreby, J Kok, L van den Berg

The high production rates achieved from mass mining methods such as block caving, sublevel caving and longwall mining require large conveyor belts, trucking loops (diesel/electrical) and rail systems for ore handling. However, the ore handling systems used in mass mines introduce a significant amount of heat into the overall ventilation system, which may be problematic at depth or in mines located in hot climates.In particular, the heat load from a conveyor system is not always well understood and consists of various components, including frictional heat from idlers, heat from electrical motors, heat from the drive train and heat from broken rock transported on the conveyor system. This paper presents results from a study that investigated the heat introduced to the ventilation air from a large conveyor system. The conveyor system transports ore with a maximum virgin rock temperature of 41°C from a depth of over 1 km. Air, belt and rock temperatures were measured in the conveyor system to evaluate the distribution of heat loads.CITATION:van den Berg, L, Moreby, R and Kok, J, 2015. Heat load estimation from conveyor systems in mass mines, in Proceedings The Australian Mine Ventilation Conference, pp 63–70 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By F M. Weir, M Fowler

The design of excavations in rock must, implicitly or explicitly take into consideration the influence of small- and large-scale geological structures. For most sites the complexity of a fractured rock mass is best captured using a 3D fracture system model based on field data. A discrete fracture network (DFN) approach involves stochastic modelling of the ‘smaller scale’, nondeterministic structures. For slope stability or tunnelling projects DFN modelling provides a valuable geotechnical tool for characterisation of a rock mass and identification of likely failure mechanisms.This paper presents a suite of the DFN modelling undertaken for the design of a large open pit in Australia. The proposed pit is to encounter a 160?m thick, high strength, sheared shale unit, which overlies a crystalline basement. DFN modelling was undertaken separately for both the shale and basement units. While the model inputs and development for each unit are briefly presented, the focus of this paper is on the various applications of the DFN modelling.A key advantage of the DFN approach for design studies is its probabilistic application to structural analyses and results. Multiple realisations of the same model were generated for both the shale and basement units, with the stability analysis carried out on each iteration. The generation of a large number of DFN models and analyses allow assessment of wedge volume, factor of safety and proportion of unstable slope for a range of conditions. The DFN modelling at the case study site was also utilised for a number of other purposes. For example, investigation of likely fault lengths in the shale unit and combined rock mass and defect failure. The development of this tool has been influential in improving our understanding of fracture networks for excavation design.CITATION:Weir, F M and Fowler, M, 2014. Rock mass characterisation and analysis for excavation design – a discrete fracture network approach, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 445–456 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

Outline of situations when valuations required - from capital raisings and takeovers, stamp duty, rates and capital gains tax, to probate and litigation between joint venture parties. Definition of types of exploration and mining properties as background to discussion on what methodologies to use (from grass roots to operating mine). Discussion on nature of alluvial deposits in New Zealand and how their characteristics and tonnage/grade uncertainties affect choice of methodology. Assessment of risk factors in New Zealand û technical, financial and socio-political (legislation, access, Maori land rights, environmental). Discussion of appropriate methodologies.

Jan 1, 1992

Safety remains a critical priority for the Australian mineral resource industry and will receive increased focus in the future. This is particularly evident in underground coal mines where reserves are becoming deeper and more hazardous to extract. The CSIRO, through its Exploration and Mining Division, have recently delivered on two projects aimed at providing step-change capabilities in real-time risk management and hazard control. This paper describes the key outcomes of these projects.

Jan 1, 2005

Societal influences, needs, and uses for recyclable materials are becoming increasingly important business and economic factors in the traditional natural resource companies. Several metals (such as steel, aluminium, zinc, lead and cadmium) are amenable ro recycle which eliminates solid waste generation and decreases the depletion of natural resources. In recent years, the non-ferrous industries have begun to recycle more materials and the next decade will see even larger recycle efforts. In addition to the traditonal recyclable materials, existing metallurgical plants are, or should be, able to handle and recycle materials viewed as 'hazardous'. Unfortunately, some national and regional regulations hinder, and in some cases prevent, the recycling of certain materials. Zinc Corporation of America (ZCA) is currently the largest producer of zinc metal in the USA and one of the world's largest producers of value-added zinc products. Over the last few years, ZCA has become one of the world's largest recyclers of zinc from various diverse materials. ZCA considers these recyclable materials as valuable 'land mines' that provide economic alternatives to the depletion of natural resources while serving society in the minimisation of solid waste disposal. Using the current production facilities of ZCA as a model, this paper overviews the recycling of zinc-bearing materials with special emphasis on: 1. the amenability for recycle within ZCA's pyrometallurgical and hydrometallurgical operations, 2. the quantities and economics of recycle, 3. the problems of recycling hindered by current national and regional regulations, 4. the concepts of total recycle rather than just recovering zinc while generating a modified solid waste, and 5. the motivators for recycling.

Jan 1, 1993

By D J. Brake

There are many sources of gas in underground mines including development and production blasting, strata gases, spontaneous combustion, diesel equipment, chemicals used for a wide range of functions, welding activities and fires.It is only in relatively recent times that electronic gas monitors (or detectors) have become both safe and affordable for routine use.In modern mines, gas monitors should be in daily use by the ventilation department as well as blasting re-entry (or clearance) crews, and are often used by drilling crews, shift supervisors, hygienists and mine rescue or fire fighting crews.When first released, electronic gas monitors needed to be sent off-site periodically for calibration at a suitable accredited laboratory. Between calibrations, their accuracy was unknown. More recently, ‘bump testing’ and field calibration has become possible on the mine site, improving both reliability and safety as well as reducing the total number of gas monitors that need to be in use.There has been almost an overwhelming increase in the number and sophistication of gas monitor features in recent years. This paper reports on a case study into the key criteria that ventilation practitioners should be aware of with respect to the specification and selection of the most recent gas monitoring systems, and recommends good practice for site-based operation and calibration.CITATION:Brake, D J, 2015. Specification and selection of hand-held gas monitors (detectors) for underground mines, in Proceedings The Australian Mine Ventilation Conference, pp 143–154 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

Wollongong* is Australia's largest single centre of mining and metallurgy. Wollongong's total employment in manufacturing of basic metal products (over 26,500 in 1972/1973) was almost 50 per cent higher than that of Newcastle and double that of any other Australian city. Although the great bulk of this employment was in steelmaking, Wollongong's copper industry was also a significant employer. Wollongong's total employment in mining (4,900 in 1971) was second only to that of Newcastle among Australian mining centres. Although the bulk of Wollongong's mining is of coal, there is also considerable mining of blue metal, sand and clay. In all, over 40 per cent of Wollongong's work force is employed in mining and metallurgy. The great bulk of the other

Jan 1, 1976

By D Clarke, I Minniakhmetov

The Olympic Dam deposit is truly a world-class IOCG-Ag deposit, the world’s fourth largest deposit of copper and the world’s largest known single uranium deposit. Traditional and non-traditional methods have been used to accurately model the geology and mineralisation of the Olympic Dam deposit. Conditional simulation models have long been used as the most robust method for estimating risk and uncertainty in mine planning decisions at other mines around Australia and the world. There are many challenges associated with simulating the Olympic Dam deposit at a selective mining unit size sufficient for underground mine planning purposes. These include the size of the deposit, resulting in hundreds of millions of grid blocks; the disseminated nature of the zoned sulfide mineralisation. And lastly the direct relationship of the relative abundances of the sulfide mineral species that are crucial to the Olympic Dam smelter performance. Several geostatistical techniques have been utilised in the workflow for the Olympic Dam Conditional Simulation model to address these challenges. The key techniques are: • Projection Pursuit Multivariate Transform to de-correlate the main elements before simulation. • Pluri-Gaussian implicit boundary simulation method to simulate the mineralisation domains. • Spectral simulation method of de-trended and de-correlated attributes with account of local varying variance. The resulting conditional simulation models have been validated against histograms, grade-tonnage curves, cross-plots and assessed for variogram reproduction. This paper presents how the final conditional simulation models compare to benchmarking models created using alternate estimation techniques of ordinary kriging and local uniform conditioning. It also presents a validation process using historical samples to test final estimate accuracy of the simulation models.

May 24, 2023

By T Day, I G. Robertson, G J. Lyman

"Various approaches are used in the industry for establishing procedures (sample mass estimation and method of subsampling) for sampling and analysis of gold ores. The key factors that determine the accuracy of the results that can be expected for a given set of procedures are widely misunderstood.Recent developments in sampling theory show that the estimation of the accuracy that can be expected for a given gold ore as a function of sample mass is actually a simple matter. For a given sample mass, the accuracy that will be achieved depends only on the grade of the ore and the range of masses of the grains of the gold in the ore. This, of course, demands that a reasonable estimate of the distribution or spread of gold grain masses in the ore be known. But this is something that should be known if the gold is to be efficiently recovered in the processing plant.This paper provides a simple explanation of the real facts about sampling of gold, either in the field or in the plant, and provides results for a number of cases of combinations of fine and coarse gold in an ore. The prerequisites for accurate gold sampling are:correct sampling with no loss of sample or contaminationsample preparation procedures that recognise the impact of the gold grain mass spreadpractical analysis of the sample masses required to provide acceptable accuracy.Issues of corporate governance are also discussed.Citation:Lyman, G J, Robertson, I G and Day, T, 2016. The Simple Facts about Sampling Gold Ores, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 159–172 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By D David

Amongst those whose task it is to design tumbling mills and other comminution machines there is an almost religious divide between devotees of the Bond method and devotees of other methods developed in more recent times. For a decade or so the issue was between the Bond power-based methods and the JKMRC (JK) simulation based approach. The newest method to challenge the status quo is power-based and was developed by Steve Morrell. As the title suggests, this paper will take some liberty at concluding that Fred Bond and Steve Morrell may be separated by history, but not by their approaches to their individual contributions to the science of comminution. Another driver for the paper is that although it is good to have diversity of thought, the existing divisions are problematic for those of us signing public disclosure documents. If alternative design methods produce materially different outcomes for the mill duty, then at least one of them is wrong or being used incorrectly. At some point the unsustainable argument may need to be put in a court of law that we metallurgists have two or more materially different design methods, each of which is correct! Therefore, perhaps a resolution is needed before this occurs?The works of both Fred Bond and Steve Morrell are each directly related to their contemporary grinding mill design and operational environments. Both their approaches are empirical, borne of observing and measuring real world situations. Both worked with theories that preceded them, gathered their own data and then each saw shortfalls in the status quo.Fred Bond was an escapee from revolution, a victim of The Great Depression, and had several near death experiences during his early site-based career. Perhaps he was fortuitously rescued from himself when asked by Allis Chalmers (A-C) to set up its rock testing laboratory in Milwaukie in 1930. Fred’s testing led him to conclude that neither the Kick nor the Von Rittinger theories explained his measurements. His writings on the failings of these old theories caused a divide between devotees of the old and new methods at that time. After many years, and much thought and plotting of data (the old way!), he came up with his now-famous equations (and his Third Theory) which have stood the test of time, certainly in the world of Bond-era machines.Coming from England via several African diamond mines, Steve Morrell immersed himself into the comminution world of the JK in Brisbane about a decade after Fred passed on. The JK had developed its semi-autogenous grinding (SAG) simulation framework using its own pendulum breakage tester, itself a derivative of the twin pendulum impact device invented by Bond decades earlier. At the JK Steve developed his authoritative Tumbling Mill Power equations and was involved in real world analysis of comminution problems on the global stage. Steve’s JK experience coincided with the demise of the rod mill, the rise of autogenous grinding (AG) and SAG milling and a rapid expansion in concentrator capacity.Morrell left the JK to pursue his own interests, which included ongoing consulting work, now demanded by the comminution world. He then turned to investigating a growing list of discrepancies between the opinions of designers and theoreticians, and the factual outcomes. The Morrell Method of design arose from this re-examination of ore testing, real world operating data and these glaring and expensive discrepancies between design and outcome. The elements necessary for a relook at the world of rock breakage were in place!CITATION:David, D, 2017. Steve and Fred would have been mates – a comminution design evolution story, in Proceedings MetPlant 2017, pp 2–11 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By L Jackson, A Parbhakar-Fox, N Fox

"Characterisation of sulfide minerals (eg pyrite, sphalerite) in historic tailings can assist in determining whether there are economic benefits of reprocessing such materials using modern metallurgical practices. In addition, there are associated environmental advantages if the historic tailings are actively generating acid and metalliferous drainage (AMD). At the Old Tailings Dam (OTD), Savage River, Western Tasmania, 38 Mt of pyritic tailings were deposited from 1967 to 1982; consequently it has been recognised as an AMD source. Long-term management options considered for this site have included the establishment of either a water, hard-engineered or vegetation cover. However, due to geotechnical challenges posed and the lack of success demonstrated by previous pilot studies, these strategies have not been implemented. Instead, resolving the pyrite chemistry can allow for a first-pass assessment of whether reprocessing these tailings is a feasible option as part of a long-term management strategy for this legacy site.Tailings samples (n = 144) were collected across the OTD from up to 2 m depth from five facies (A–E), and four zones (1 to 4; defined by hydrological regime and grain size). These materials were subjected to acid-base accounting (ABA) and mineralogical evaluations to determine their geoenvironmental characteristics. Following this, 26 samples were selected for in-depth laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) investigations to evaluate pyrite chemistry across different tailings facies. The results revealed enrichment of Co and Ni in these materials. Specifically, Co content was up to 3.0 wt per cent, particularly within facies C to E, and Zones 3 and 4. Cobalt is recognised as a critical metal, therefore, reprocessing should be considered as a future rehabilitation option for the OTD, pending resource definition using established codes and practices.CITATION:Parbhakar-Fox, A, Fox, N and Jackson, L, 2016. Geometallurgical Evaluations of Mine Waste – an Example from the Old Tailings Dam, Savage River, Tasmania, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 193–204 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By K J. McDonald

All commercially available zircon sands contain radioactivity sourcing from the decay of trace amounts of contained uranium (U) and thorium (Th). The fine particle size zircons of the Horsham area in the Murray Basin region of Victoria, Australia, contain significantly more (about twice) Th+U than those commercial zircon sands. The marketability of these fine-grained zircon sands is likely to rely on the removal of these radioactive impurities. CSIRO Minerals have been working for some time to develop processes for the removal of the radioactive impurities from zircon. It is generally agreed that it is quite impossible to leach U and Th from zircon, however, the Heat and Leach (HL) process, described in detail in Aral and McDonald (1999), reduces the radionuclide levels significantly. The identified (HL) process aims to leach uranium and thorium selectively from a decomposed zircon. The novelty of the process is that a large part of the leached product can be reconstituted to a low radiation zircon by a subsequent heat treatment. The HL process uses a flux mixture of sodium carbonate and calcium borate to decompose the zircon at relatively low temperatures (900 to 1150¦C) and a weak acid (0.5M HNO3; 80¦C/0.5 h; pulp density ten per cent) to leach the radionuclides selectively. The process leaves the major components (ZrO2 and SiO2) behind with little loss. The HL process for example lowers the U+Th content of a Murray Basin zircon from 1000 ppm to 400 ppm U+Th. Among the radionuclides more U progeny is removed than the Th series radionuclides. This is very significant as the radioactivity of U series is 2.5 times more that from the Th series. Therefore the reduction in the radioactivity level of zircon is more than the reduction in Th+U indicated by XRF analysis. A schematic flow sheet of the HL process is shown in Figure 1. Although the HL process successfully lowers the radionuclide levels in zircon sands, the final product contains significant amounts of sodium (up to 14 per cent Na2O) and small amounts of CaO. By comparison, the sodium content of the commercial zircon sands is in general 2O. Zircon is used mainly as an opacifier in tile glazing where the addition of ten to 15 per cent zircon to a translucent base glaze gives the sanitary white colour to the tile surface. Opacification is the result of the refractoriness of zircon particles at the glaze firing temperatures that is generally around 1050¦C.

Jan 1, 2001

By E N. Sparg, O D. A Deuchar, F Needham

Decline shafts are an attractive option to both new and existing mining operations where there is a need to access an inclined orebody deposit via on-reef development so as to generate a return in the shortest possible time. There are many different technologies that are available to transport men, material and rock in incline shafts. This paper focuses on the applicability of two hoisting technologies for decline shafts, namely endless and direct rope systems. The pros and cons of each system are reviewed. A common concern with direct rope haulage systems is the possibility of generating slack rope during deceleration. This paper illustrates the issues involved in designing a system so as to avoid the possibility of slack rope. In conclusion, the key factors relevant to the selection of endless or direct rope haulages for a particular decline application are reviewed. The paper is a joint submission by FFE Minerals-Vecor and Qualter Hall UK.

Jan 1, 2005

The arbitration process, and its drawbacks: Any time you have taken part in a major arbitration, and the decision, when it comes out, is not what you thought it would be (which is bound to happen occasionally), the normal reaction is something like æthe arbitrator got it wrongÆ. Again normally, when you have cooled down a bit, and you look in more detail at the decision, you can see, probably, æwhere he got it wrongÆ (it is only male arbitrators who get it wrong). Ultimately, when reason prevails, and you reflect on it, you can see that what really happened was that you failed to get the arbitrator to see what you were getting at in the point or points concerned. This is doubly frustrating, when you consider what has been involved in getting to this point, having been through it all at least twice. An alternative to this process may be the dispute review board.

Jan 1, 1999

By A G. L Pratt

Change and its relationship with the introduction of new technology is a constant of human history. The mining industry has many examples of this relationship. This record contrasts with its present day struggles to move beyond a public perception of being just ‘dirty, dumb and dangerous’. The drivers for the introduction of new technology are frequently listed as the occupational health and safety of people working in the mines, reductions in direct operating costs, and increases in productivity.This paper discusses the issues that a mining business needs to deal with to implement new technology with the best possible conditions for success. It comments on how the strategic and tactical components of technology planning relate to and interact with change management. The central discussion is directed at the role that people play in the successful implementation of new technology. The introduction of autonomous underground haulage equipment provides a background for the discussion of this topic.The paper uses case study references, equipment supplier information and research findings. The aim is to offer a high-level view of the issues a mine operator needs to consider when approaching the introduction of new technologies for underground mining.CITATION:Pratt, A G L, 2017. Technology change in underground mining – things to consider, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 103–114 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By A Marton

Concerns with crest losses have seen changes to a number of design and operating parameters to retain the integrity of the wall and the berms of the Kidston Gold MinesÆ Eldridge Pit. Until trials began in 1999 most final wall designs utilised large diameter blastholes up to the presplit row to achieve the wall angle. The berm crests were being lost, wall support requirements were increasing and affecting mining schedules and several fault areas were putting pit access at risk. Standard designs had been determined during the early mining years and while periodic modifications had been made there was a need for major blast pattern revision. This paper traces the development of wall control blasting programs over the years, relating designs to the geology and the evidence in the walls with the theories of the day and includes the recent trials that were conducted in what is a most unforgiving geology. Trials and improvements to ensure the walls were safe were conducted even as the mine neared its economic life. Instrumented monitoring of trials blasts has greatly increased the understanding of the damage criteria and enabled rapid revision of designs. Recent changes included reduction in presplit energy, charge redistribution and use of smaller blast holes for the trim patterns. Determination of a minimum proximity-to-final wall limit for production blastholes, establishment of the correct standoff to berm crests and walls and selective use of presplitting techniques for protecting crests have resulted in cost effectiveness, improved bench crest retention and an overall reduction in visible wall damage.

Jan 1, 2001