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Within ten months of the first significant intersection on the Vera deposit, approval was given to proceed with a $28.3 M underground development of the Vera-Nancy gold mine. Contrary to what the timeframe suggests, the development of the underground mine was planned in a logical and methodical manner which enabled confirmation of the resource, evaluation of the orebody for mining and sufficient production to recommence milling operations at the Pajingo treatment plant. This paper describes the underlying factors on which the project was planned and developed. The approach has successfully enabled the mine to be in production 18 months after discovery without compromising any future production or potential expansion

Jan 1, 1998

Iron Concentrate Synthesised from Waste Ferrous Sulfate Produced in Titanium White Preparation

Sep 13, 2010

Project-finance risk assessment is mature and approached systematically. Mining industry due diligence remains fragmented with specialists addressing different aspects of the project such as reserves/JORC, environmental impact, commodity market, even financial analysis/ modelling. Each professional has a natural tendency to believe that the risk factors they have examined are the key ones necessary to be reviewed, as if their review will stand in isolation from others in the way a project materialises. By first laying out the project risk categories and risk matrices, this paper examines the due diligence process with a keen eye to the risk assessment and overlap/interaction. Some cross fertilisation of due diligence techniques from other industry sectors is placed into the mining context. Six case studies are then presented with regards to due diligence features in each projectÆs feasibility review or financial information/ offering memorandum. A power case first shows the differences between the due diligence expectations of banks versus bond financings. Then some Australian and Indonesian mining development cases are analysed to see the due diligence learning points. Some of these were project/due diligence failures. The conclusion focuses on the value of a systematic risk assessment for project evaluation, all from the project-finance perspective.

Jan 1, 2007

Correlation of Air Recovery with Thin Film and Froth Stability in Flotation

Sep 13, 2010

Prediction of fragmentation by blasting is most commonly based on theassumption that a single distribution of pre-existing discontinuities is present within a blasted rock volume and that the underlying mechanism of failure is tensile failure. It is assumed that the tensile stress field created by a blast initiates and extends radial cracks around the blastholes. Interaction between radial cracks from different blastholes and the free surface creates rock fragments. In reality, fragmentation of the rock occurs due to two mechanisms.One is related to the compressive-shear failure of the rock (mainly rock matrix) close to the blastholes, while the second mechanism is the previously mentioned tensile failure of the rock mass. The secondmechanism of failure occurs in the form of extension of the larger cracks in the region beyond the crushed rock, and this type of fragmentation occurs after the crushing phase. In the case of hard rock or blasting where the extent of crushing is minimal, the currently used prediction methods give a reasonably good result. However, there are many blasting conditions where the amount of rock crushing is significant. In the case where fragmentation of the given rock volume occurs dueto two different mechanisms, modeling of the rock fragmentation with a single distribution function is not appropriate. To model the fragment size distribution generated by two different mechanisms, it is necessary to use a two-component fragment size distribution function and a scaling parameter that will determine the proportion of the fragmented volume created by each mechanism. The purpose of this paper is to present results of blast fragmentation modeling based on two mechanisms of failure. The two-component model (TCM) utilises experimentally determined parameters from small scale blasting and parameters of the Kuz-Ram model, for more accurate prediction of the complete rock fragment size distribution curve. The methodology is such that it is possible to predict complete fragment size distribution, including fines, of ROM product for a future mine, at the feasibility phase of mine design.

Jan 1, 1999

By J R. Leeming

Mining law has developed in Great Britain (GB) over centuries, mainly in response to lessons learned after disasters and other major incidents. This has led to a culture of preventing repeat accidents, rather than predicting and controlling unsafe acts or conditions.This paper explains how, initially in response to a government drive to reduce the burden on industry, the opportunity was taken to review and reform all 48 sets of GB mining-specific law into a single document. The philosophy adopted, the procedure followed and the significant changes that resulted are explained.CITATION:Leeming, J R, 2017. The complete renewal of Great Britain’s mining laws for the 21st century, in Proceedings Australian Mine Vent Conference 2017, pp 3–8 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

India is on fast economic growth. Even in the turbulent years of global crisis, it could achieve a growth of over eight per cent. In recent past, Indian Government has been contemplating a faster growth in all the sectors of economy so as to make the nation an economic power in the world.Steel is a versatile material. It has its role in most of the major industrial activities, such as infrastructure, automobiles, urbanisation, consumer durables and other. In other words, steel is a part and parcel of industrial expansion, urban and rural development. It is rightly admitted that steel acts as pillar of any development model. Volume of steel consumption is the barometer which measures economic progress and/or industrial status of any country.India and China are the two countries in Asia which have the significant impact on the global steel industry. Of course, China is much ahead of India in consumption level of steel.

Dec 6, 2010

Study on the Reasonable Mineral Processing Technology of a Cu-Mo Ore

Sep 13, 2010

The Clyde Power Project, and its Clutha Valley Development forerunner, has taken widespread investigations for various hydroelectric purposes both along the valley floors upstream from Alexandra and on the higher schist terrain. As part of this work the nature and extent of many of the alluvial deposits have been resolved and the ages established with varying precision. Gold values have been approximately appraised in some areas as an element of environmental assessment.

Jan 1, 1992

I have spent most of the past 35 years working as an economic geologist in the area of exploration and development of base and precious metals. Most of this period has been as an employee of Trans-National-Corporations (TNC's). I presently act as a consulting geologist to a joint venture company, bringing together two such TNC's: Anglo American Corporation and affiliated companies De Beers (Diamonds) and Minorco (Metals mining outside of Southern Africa), and Normandy Mining Limited ofAustralia. Normandy is presently through its gold arm PosGold, Australia's largest gold miner and Anglo American can claim to be the world's largest gold company producing over 280 tonnes of gold a year, more than twice its nearest rival Gold Fields of South Africa. In addressing this topic, the role that Government can, and should play in mineral development, I will be drawing heavily on some examples from these and other TNC's experience in recent offshore mining investment.

Jan 1, 1995

By A B. Christie

The Institute of Geological and Nuclear Sciences' Mineral Resources Programme is currently carrying out research under two major projects:   HAREM (Hauraki Andesite Rhyolite Epithennal Mineralisation) The Hauraki Goldfield lies within a belt of andesite-dacite-rhyolite volcanics of Miocene Pliocene age which is underlain by a basement of Mesozoic greywacke. It contains some 50 separate epithermal gold deposits and is a world-class gold and silver producer. The HAREM project is aimed at improving models of the epithermal gold mineralisation, and to better understand the processes and controls of origin, transport and deposition of the gold.   MARGO - (Marlborough Gold) The MARGO project is aimed at determining the geological factors that controlled the formation of the Mesozoic mesothermal gold-antimony-tungsten deposits in the Marlborough Schist belt. Following reconnaissance work on 12 deposits, our current work is concentrated on deposits in the Wakamarina valley.

Jan 1, 1994

By W J. Cowie

Several years of operating experience of over 100 gold recovery operations on the West Coast has provided a database from which the basic operating costs of these types of operations can be characterised. Using figures generated from the averaging of plant operating costs throughout the region and financial modelling using Lotus spreadsheets has been developed to analyse both existing and proposed developments. This type of modelling has several uses: 1. Identification of the impact on profitability of changes in management practices, finance costs, operating costs and revenue streams. 2. Project evaluation and planning. 3. Profitability projections for development financing. 4. Troubleshooting with existing operations. 5. Valuation of existing operations and properties.

Jan 1, 1987

Hydraulic mining shovels can be successively used at open-pit mining operation in severe climatic zone with air temperature interval from -700C to +450C typical for some northern region of the world particularly of Russia, Canada and Sweden, if they would be equipped by special preheating facilities for their diesel engine, water, hydraulic oil and lubrication systems. All shovels manufactured by the Komatsu Mining Germany GmbH for operation at ambient air temperatures down to -50¦C have cast and forged structural design elements, bolted connections made of special steel grades, electric cables with special insulation, flexible high-pressure hoses manufactured by ICE-Champion with connectors made of special steel grades.Generally at the temperatures below -25¦C the ordinary machine has to be stopped, the attachment should be placed in the parking position, the generator should be switched on, or the external electrical power supply connected, for the preheating equipment. For rapid start-up in winter after a long shutdown of a hydraulic shovel, there is a procedure for preheating of the main systems. It is applied for the following systems: engine cooling system, engine oil, hydraulic oil, pumps and drive motors of the propel gears, electric cabinets, machinery house, especially near the ventilation inlets and outlets.Start-up of the main drive engine is permitted at a hydraulic oil temperature of -20¦C, when it has a viscosity of 1000 cSt. In this case the rotation speed of the diesel engine crankshaft is lower by two times than the nominal value and this is the most favourable condition of start-up of the engine and hydraulic pumps and motors, which work with half of their rated rotation speed until the hydraulic oil reaches a viscosity from 100 to 10 cSt. After that the hydraulic system and the entire shovel begin to operate under normal conditions.

Dec 6, 2010

Predicting Flotation Response from Liberation Information

Sep 13, 2010

A search for the keyword nano reveals that it has not made a significant entry into the mineral processing research literature. In contrast, the terms micelle, colloid, interface, and monolayer are well established there. By considering nanoscience as colloid and interface science at the nanoscale, it is claimed that several previous and current investigations in the broad field of mineral processing fall under the umbrella of nanoscience. Several examples from hydrometallurgical processing systems (invisible gold and activated carbon in gold extraction; monolayers, reverse micelles, and microemulsions in solvent extraction; nanobiofilms and nanoparticles in biohydrometallurgy) are highlighted in support of this view.

Sep 13, 2010

By R Sridhar, M Fe, W G. Bacon

The problems of magnetite build-up have plagued the non-ferrous pyrometallurgical industry for many years. To better understand these problems, a study was undertaken to determine the thermodynamic variables that affect the behaviour of magnetite under different smelting conditions. Equilibration studies were performed in the nickel smelting systems of matte-gas and matte-slag(silica saturation)-gas. The relationship of thermodynamic variables such as temperature, sulphur and oxygen partial pressure and matte grade on iron and magnetite activities were calculated and the significance on smelting parameters such as metal losses and partition coefficients were defined. The experimental data from this study were employed to develop practical methods which could be used to control the build up of magnetite, as well as to obtain additional metallurgical benefits. In general, a lower sulphur partial pressure and higher temperature operation was shown to enhance the metallurgical benefits of nickel smelting by decreasing the magnetite activity. Operating in this manner can also have added benefits such as higher metal recoveries, more efficient vessel utilisation and efficiency and lower smelter emissions at equivalent or higher primary furnace matte grades.

Jan 1, 2000

Estimating Breakage of Fine Ore Particles by Media in a Small Ball Mill Using DEM

Sep 13, 2010

The ERMS Process was developed during four years of testwork by Austpac Gold NL to overcome the severe metallurgical problems of the ilmenite atWestport, in the South Island. These deposits have been known for about one hundred years. They were originally mined for gold, and only later attracted attention as a possible source of titanium minerals.   The resource is of world scale and may exceed 20 million tonnes of contained ilmenite. Similar deposits occur at Barrytown further south and together these areas would constitute an important opportunity for export-oriented mineral development, if a viable beneficiation technology were available. Further processing is essential, as the composition of the ilmenite is well below market specifications.

Jan 1, 1993

Maghemite - A Source of Heavy Medium for Coal Washeries Use of magnetite as heavy medium in coal preparation plants has been increasing steadily in recent years. It might be in short supply in some areas or excessively costly in certain times. In Turkey, the cost of heavy medium magnetite has almost tripled since 2003. As a result, alternative sources of heavy medium material have been evaluated. A maghemite ore from Elbistan-Kahramanmaras was found to be an interesting source. Tests showed that the maghemite ore can be enriched via magnetic separation at 1556 gauss to obtain a heavy medium material with 4.93 g/cm3 density and 97.22 per cent magnetic recovery. Further tests were conducted to determine the optimum field strength for magnetic separation, friability and regeneration recovery.

Sep 13, 2010

By P McCarthy

"This paper is based on 30 years of involvement in feasibility studies as a participant, study manager and the leader of a firm that provides study components and overall study management. The following topics are discussed:the purpose of feasibility studiesaligning the goals of the study team with those of the ownerthe difference between optimisation and designhow the types and levels of studies affect the organisation of the studythe relative merits of various management structures and contractual arrangementssetting scopes of work and tendering the work outthe selection of a study manager and the study management teamcommunications within the study team and externallythe project management trianglemanaging scope changes and maintaining flexibility to respond to study findingsprogress paymentsmanaging a study crisisinnovation, risk aversion and bankabilityreporting the resultsthe dangers and benefits of value engineering.CITATION:McCarthy, P, 2016. Making studies work – organisation, communication and management, in Proceedings Project Evaluation 2016, pp 20–30 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016