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By J T. Carswell

Best practice mine sampling should provide a detailed quantification of all potential sources of error at each stage of sampling, sample preparation and assaying.Quality assurance (QA) should include testing for and quantifying potential sampling errors, and should be the basis for establishing ongoing sampling protocols, should set error limits and define quality control (QC) procedures. QA should be within the framework of Theory of Sampling (TOS) but may not involve the estimation of the sampling constant and the application of Gy’s formula.Best practice QC should be carried out efficiently and in a timely and cost-effective manner with regular reporting against the guidelines established by QA.This paper provides an assessment of, and checklist for, current best practice sampling QA/QC with examples from operating gold mines including the QA/QC of underground (UG) reverse circulation (RC) grade control.CITATION:Carswell, J T, 2017. Best practice sampling QA/QC for gold and base metal mining – including how to assess the applicability of underground reverse circulation grade control sampling, in Proceedings Tenth International Mining Geology Conference 2017, pp 297–304 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By B J. Hutchison, S Gannon, J Chambers, D Oko-oboh

The Kanmantoo copper mine is located in the Adelaide Hills area of South Australia and is owned and operated by Hillgrove Resources (HGO). The mine is a drill and blast, truck and shovel operation mining sulfide (chalcopyrite) ore located in chloritised andalusite biotite schist. The initial Kanmantoo open pit operation occurred in the 1970s, before falling copper prices closed the mine. In 2010 the mine was reopened by HGO and the Kavanagh cutback of the Kanmantoo pit was undertaken. The Spitfire, Nugent and Emily Star satellite pits were also mined through to 2015 before the latest steep wall Giant pit design was developed to take mining out to 2019.There are no major fault structures and only two significant shear zone structures exposed in the open pit walls. The main Garnet Andalusite Biotite Schist (GABS) unit is quite competent so the pit designs have therefore mainly been controlled by four distinct joint sets. This paper is a case study on the influence of the joint regime on the wall stability of the main GABS unit and how a better understanding of the joint regime and the use of rock reinforcement has allowed the steep wall design to be adopted.The paper also describes the remote geotechnical mapping and slope monitoring techniques used to manage the rockfall risks associated with the steep walled slope design.CITATION:Hutchison, B J, Chambers, J, Gannon, S and Oko-oboh, D, 2017. Case study of joint structure and the design and performance of open pit walls at the Kanmantoo copper mine, in Proceedings Tenth International Mining Geology Conference 2017, pp 355–364 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

Study of Bauxite Separation by Using Flotation Column

Sep 13, 2010

The new generation Hlsmelt« Direct Iron Ore Smelting Process is a CRA Limited technology initiative. The process development is now focussed on commercialisation. The goal is to have the first commercial vessel operating around the year 2000. The HIsmelt« Process, based on the abundantly available iron ore fines and the more readily available non-coking coals, has the potential to fundamentally change iron ore processing through the application of high intensity techniques to replace the current sinter/coke ovens/blast furnace .technologies. The process will have great potential in the rapidly growing economies of Asia where steelmaking aspirations are based around local market focussed plants. This potential can be. realised as a supplier of premium grade iron units to electric arc furnace (EAF) steelmaking plants or as the front end to an ore based steel mill.

Jan 1, 1996

By H Durrant, P I. Corke, J Cunningham

This paper reviews the state-of-the-art in the automation of underground mining vehicles and reports on the development of an autonomous navigation system under development through the CMTE with sponsorship arranged by AMIRA. Past attempts at automating LHDs and haul trucks are described and their particular strengths and weaknesses are discussed. The auto-guidance system being developed overcomes some of the limitations of state-of-the-art prototype æcommercialÆ systems. It can be retrofitted to existing remote controlled vehicles, uses minimum installed infrastructure and is flexible enough for rapid relocation to alternate routes. The navigation techniques use data fusion of two separate sets of sensors combining natural feature recognition, nodal maps and inertial navigation techniques. Collision detection is incorporated and people and other traffic are excluded from the tramming area. This paper describes the work being done by the group with regard to auto-tramming and also outlines the future goals.

Jan 1, 1998

The principal source of funding the working capital requirements of gold miners has traditionally been equity. However in the 1980s, with a substantial increase in activity in the exploration for, and the production of, gold the traditional sources of equity finance became no longer sufficient to meet demand. With the often high cost of raising equity, the need for developing alternative financing structures became critical, especially since the stockmarket crash of 1987 which at least until recently, adversely affected the amount of equity capital available for investment in mining.

Jan 1, 1994

This paper presents a summary of tools and methods used for geotechnical assessments and monitoring systems at block caving mines. A critical review of these tools is given based on the authorÆs experience in block caving operations. The reviewed tools include cavability prediction, fragmentation evaluation, geotechnical monitoring systems, numerical stress analysis and others. Some of these tools have been developed under certain circumstances in particular mines and experience shows that their applications under different geological and mining conditions have often been difficult. Examples from block cave mines are also utilised in this paper to illustrate the importance of the further development of these tools, whilst possible improvements on these tools are also suggested.

Jan 1, 2000

By D N. B Skinner, R L. Brathwaite, M S. Rattenbury

The Institute of Geological and Nuclear Sciences is undertaking a mineral resource assessment study of the Coromandel region, due for completion in July 2000. A key part of the study is the assembly of a geographic information system (GIS), a computerised tool for layering, analysing and presenting spatial information. The GIS is being assembled with ArcInfo/ArcView software and to date includes layers for a digital terrain model, an aeromagnetic map (open file mining company data), a geological map (from the QMAP project), areas of hydrothermal alteration, locations of mineral deposits (GERM database), stream sediment geochemical analyses (REGCHEM database), and a lineament map derived from satellite remote sensing data.

Jan 1, 1999

Wheal Gawler was Australia's first metal mine. This leader was followed by an army of other metalliferous underground mines and surface operations in Australia. As a mine it was not highly significant economically because its small total production of nearly pure galena had low multiplier effects on the economy of South Aus- tralia. Its importance lay in its symbolism: here was a silver-lead mine close to the new town of Adelaide posing the question of what other min- erals lay in the Mount Lofty ranges and in the fields beyond.

Jan 1, 1987

Technology is playing an increasingly large role in the operations of our mines. There is a temptation to regard the implementation of technological systems as the objective itself when, in reality, systems are used to support a business process. Only when the process succeeds will the systems be seen to succeed. Understanding the distinction between system and process is critical. This understanding, together with the resultant holistic approach, is considered to be critical to successful implementation and operation of Mine Control process. This paper examines the critical factors essential to success in establishing and sustaining a Mine Control process that maximises benefits to an operation. These factors have been developed during the author's experience of nearly 30 years in Mine Control projects across over 50 sites. Each factor is discussed in relation to real world examples at well-known mines.

May 1, 2010

Timely disclosure of information germane to the taking of investment decisions makes an essential contribution to ensuring the growth, efficiency and integrity of our capital markets. It is a core contributor to the maintenance of fair, orderly and transparent markets. Australia has a strategic need to protect and enhance market integrity. Australia is ranked tenth in the Morgan Stanley Capital International (MSCI) World Index, yet represents only 1.59 per cent of that Index. In order to survive and grow in this globally competitive environment, Australian capital markets û the drivers for economic activity in Australia û need to attract foreign investment and engage retail capital. The communication of relevant and comprehensible information to the investor plays a vital part in fostering investor confidence, thereby building depth and liquidity in our market. We have had a rewarding partnership with the mining industry to develop and recognise reporting standards which could allow ready comparability and investor understanding of the mining investment vehicle. Our mining market has been successful because of the high standards of professionalism and the intellectual capital that has been built up among the participants û the mining professionals, brokers, analysts, mining investors, professional advisers and the market operator. The balance of knowledge and understanding among these participants combined with the competition for capital, contributes to the standards for our mining market in a way that the market operator simply cannot replicate by market rules alone.

Jan 1, 2002

By M Simpson, K Brodie, J L. Mauk

Subaqueous water-rock reactions that occur at the pit wall/lake water interface can affect the pH of pit lakes. Many pit lake water chemistry models neglect subaqueous reactions, which may create inaccurate predictions over time. A mineral quantification method is presented that defines the wall rock mineralogy of active open pit mines, using samples collected from the Martha Mine, a low-sulfidation epithermal Au-Ag deposit in Waihi, New Zealand. The mineral quantification method has five components: field observations and sampling, X-ray diffraction analyses, selection of representative samples, geochemical analyses, and mineral accounting. Predicted mineral concentrations closely match observed mineral concentrations visually estimated using petrographic techniques. Results of the method can be incorporated into a geochemical model of long-range pit lake water quality resulting from subaqueous water-rock reactions.

Jan 1, 2003

Anglo American Metallurgical Coal (AAMC) manages five open cut coal mines in Queensland and New South Wales, producing approximately 30 million tonnes per annum. The size and complexity of these mines require efforts by a large and diverse number of personnel to minimise adverse geotechnical events from occurring. To achieve this, the AAMC coal mines in Australia are developing a concept of managing the geotechnical risks associated with open cut coal mines. The overall system utilises a combination of internal training, a management system (operational management systems) and standards, numerical modelling, monitoring, inspections and audits. The development of the standards as well as training and mentoring of exploration personnel, geotechnical engineers, engineering geologists and mining engineers with an interest in the geotechnical aspects of mining, training of the production workforce, mentoring and training of the technical staff create the basis for achieving a pro-active rather than a reactive system. Audits are used to assure that personnel are maintaining the standards and to facilitate cross-mine leanings so that best practices are developed across all sites.

Nov 25, 2010

By Case JE

Complete Bouguer and isostatic anomaly maps compiled for Costa Rica provide new insights into the crustal structure and mineralization. Terrain corrections were approximated from the station to a radial distance of 167 km by computer using a 3- minute digital elevation model of Costa Rica and surrounding areas. Isostatic corrections, based on Airy-Heiskanen compensation, were also calculated from 0 to 167 km using the 3- minute elevation model and from 167 km to 180 degrees using combined topographic and isostatic reduction maps. Costa Rica can be divided into four main terranes based on gravity data: a Pacific coastal region, a Pacific inland area, a central region, and a Caribbean coastal region. Negative gravity anomalies along the Pacific coastal margin correlate with an offshore sedimentary basin, and large positive anomalies correlate with mafic and ultramafic igneous rocks on the Santa Elena, Nicoya, and Osa Peninsulas, and at Puerto Quepos. Pacific inland anomalies are separated from the Pacific coastal region by a steep gravity gradient, and over the Coast Ranges a major gravity low overlies a thick section of low- density sedimentary rocks. In the central region, a major gravity low occurs over a thick low-density Quaternary volcanic complex in the Cordillera Central, north of San Jose. A prominent feature of the Caribbean coastal region is an interrupted gravity low over the Limon Basin that reflects a thickening of low-density sedimentary rocks. A conspicuous gravity lineament, trending northeast separates northern and southern Costa Rica. The lineament is defined by the termination of several major gravity anomalies including those over the Coast Ranges, Cordillera Central, Puerto Quepos, and Limon Basin. In addition, the lineament correlates with other geological and geophysical data including: northeast-trending faults, the southern limit of large Quaternary volcanoes, the segmentation of the middle America volcanic belt, and a seismicity gap. This lineament may be the expression of a previously unrecognized major northeast- trending fracture zone in central Costa Rica. An important economic implication of the gravity lineament is a correlation with the termination of gold and porphyry copper deposits in Costa Rica.

Jan 1, 1987

This paper addresses the role of mine geology in mining geotechnics. The role is assessed and discussed in terms of five main elements; geotechnical complexity, geological complexity, mine scale, percentage sampling and geological uncertainty. Lastly, the overall objectives and mine geology requirements are listed in terms of the various mine development stages; exploration, feasibility-design and operating.

Jan 1, 1993

By Kitzinger F

The economic climate of the Canadian mining industry forced an increased interest in rapid, continuous excavation techniques for hard rock formations. The potential applications and advantages of continuous mining over the present drill- blast-muck labour intensive cyclical methods are considerable. Noranda investigated an electrical technique, Plasma Blasting showing considerable promise for mining hard rock. The background of the technology and the theory of blasting rock with electricity is described. The Plasma Blasting process is based on the fast discharge of stored electrical energy into a small amount of electrolyte, suitably located in the rock. The electrical energy converts the electrolyte into high pressure plasma, which expands very quickly, thereby, generating a shock wave. This shock wave produces a stress field inside the rock, resulting in a blast similar to that made by chemical explosives, but without the deleterious fumes. Noranda is currently blasting boulders of 4-5 tonnes and is at present constructing a mobile, autonomous secondary rock breaker for underground and open pit applications. Tests on in situ hard rock formations will lead to the development of a continuous mining machine. Production rates of 500 tonnes per man-shift could be obtained with such a machine.

Jan 1, 1990

By R Simonato

It is now recognised that rotary sample division is by far the best laboratory tool for extracting subsamples from a lot of material. In terms of sampling theory, rotary division, by virtue of the fact that it can extract many increments from the lot during the division process, radically reduces the variance due to distributional heterogeneity in the sample being divided. There are a number of occasions in sample preparation when it is necessary to extract a subsample of a target mass. To do this with rotary dividers taking a fixed fraction of the starting mass is a tedious task. In response to this problem, a variable split sample divider has been designed and built for the mineral industry. This paper discusses the utility of the device and presents test data showing that the machine is capable of making accurate mass split while overcoming segregation in the material being divided.

Jan 1, 2008

By Medhurst TP, Trueman R

The aim of the paper was to model numerically some aspects of the extraction of coal pillars by split and fendering. A two-dimensional elasto-plastic plane strain model with strain softening and interface mod- elling was used. The model was able to simulate the improvement of conditions experienced in lifting from the fender, when the roof adjacent to the fender has caved. In contrast, when a stook was left, providing support to a span of uncaved roof, the model pre- dicted the fender would suffer considerably more de- formation and strain.

Jan 1, 1992

Although the last decade has seen the growth of many new licencing and approval requirements for the exploration and mining industries, there remains in each State of Australia and the Northern Territory a predominant "Mining Act" containing provisions for the grant of exploration and mining tenements. What then are the rights and duties of tenement holders either by virtue of a Mining Act or through other approval and licencing mechanisms? What rights and duties does a person acquire when he is granted an exploration licence or a mining lease? In this paper I will attempt to cover these types of questions using in particular examples from New South Wales. I will also refer to a range of other subordinate approvals and licences which today's society requires and the need for ethics and recognition of liabilities.

Jan 1, 1995

By V L. Los, G J. Abramson

The paper examines three types of polar zoning of ore-forming and associated elements that can be detected from geochemical data. Polar zoning is mapped in the form of geochemical ore systems of various ranks. Various types of polar zoning can be found in some systems, which present a general geochemical model of the ore object. The genetic basis of zoning is examined from the perspective of the conception of geoelectrochemical redistribution of matter, including ore-forming elements. The volume of the geochemical ore system may be used in the prognosis of resources for every rank.

Jan 1, 1999