Search Documents

By Miskelly N

In Australia and New Zealand, the 'Australasian Code for Reporting of Identified Mineral Resources and Ore Reserves', which was released by industry in 1989, is operating successfully in a co-operative approach between industry and regulatory authorities. Similar codes or guidelines exist or are under development in the United States of America, Canada, the United Kingdom and South Africa, although the regulatory backing given to the Australasian Code is unique. International standard definitions for Mineral Resources and Reserves, and for categories of Resources and Reserves, have been under development by the Council of Mining and Metallurgical Institutions since 1994 and have already stimulated considerable convergence of definitions and reporting standards in participating countries. It is hoped that agreement on this international standard for public reporting by mining companies will be reached within the next two years, and it is expected that adoption of the standard will result in a higher and more uniform quality of reporting worldwide, with a consequently greater interest on the part of the general public and financiers in investing in the mining industry.

Jan 1, 1997

The mineral resource that a mining company has access to, represents the majority of the embedded value that exists within the company, as well as the competitive advantage that the company has over its peers. However, the real value is only realised once effective mining plans have been put in place, which optimise the extraction of the resource, and add measurable value to the company. The concept of mineral resource management (MRM) has been developed in South Africa, to ensure this optimisation happens in an integrated and quantifiable manner, such that value is added and risk is reduced, resulting in bottom line improvement for the stakeholders of the business. This paper describes the process of mineral resource management, and draws on successes and failures of various companies, to illustrate how it should be implemented, and what measures should be put in place to ensure its success. This requires a fundamental re-appraisal of the way in which mining companies plan and execute their businesses, and focuses attention on real value adding activities and behaviour through the use of economic value added as an appropriate metric by which to measure real value and risk. Specifically, the paper focuses on these aspects as applied to planning models and processes, exploration activity and risk management, to ensure operational and project success.

Jan 1, 2006

The results from three quick methods for the determination of W03 in scheelite ore samples, mill products and concentrates were compared with gravimetric results and tested with standard samples to establish which was the most reliable. Summaries of the methods, two X-Ray fluorescence and one colorimetric, are given. The best method was X-Ray fluorescence, with samples cast as glass discs.

Jan 1, 1988

By Dai Q

The mechanism of flotation of potash ores with long chain primary amines has been assessed. Since at high electrolyte concentration in saturated brine the electrical double layers of the interacting particles and bubbles are entirely compressed, the induction time measurements confirmed the elimination of kinetic factors associated with the energy barriers opposing particle-to-bubble attachment under such conditions as could be expected. The lack of the kinetic hindrance resulted in the correlation found between the contact angles on the KCl surfaces and the sylvite flotation measured under the same physico-chemical conditions. The iep values and acid numbers obtained for various Esso oils tested as extenders in the flotation of coarse potash ore fractions confirmed the base oils with high content of nitrogen-bearing compounds to be good extender oils. The performance of such oils could further be improved by dissolving in them a small amount of long-chain aliphatic amine.

Jan 1, 1993

By L Lagoeiro

The samples studied in this paper were derived from the iron oxide facies of iron formations (IFs) of the Quadrilßtero Ferrffero, south-eastern Brazil. The rich-iron oxide varieties of the IFs can be regarded as Fe-O systems because they consist predominantly of aggregates of haematite and magnetite crystals. The study was based on carefully selected samples in which magnetite crystals occur as isolated large crystals set in a matrix of haematite grains. Optical microscopy and an electron microscope equipped with an electron backscattered diffraction (EBSD) system were used to investigate the microstructural and crystallographic relationships involved in the phase transformation between magnetite and haematite. The magnetite crystals in the IF samples are partially transformed to haematite and this process is also known as martitisation. This transformation occurs along the crystallographic planes {111} of the magnetite producing a characteristic triangular pattern of interlocking lamellae of transformed haematite crystals that are oriented parallel to octahedral plane {111}. This new generation of haematite is referred to martite because of the martitisation process. EBSD analyses show that the magnetite and the new haematite crystals, martite, share crystallographic planes of highest atomic density, eg {111} and (0001), respectively, possibly due to the ccp and hcp atomic arrangement of the two crystals. Stereographic projections of these two planes therefore coincide when the maxima of their poles are plotted. However, the crystallographic orientation of the haematite crystals in the matrix shows maxima of (0001) poles that do not coincide with those of {111} planes of magnetite. Consequently, it is concluded that the direct transformation to haematite crystals retains the crystallographic orientation memory of the former magnetite crystals, possibly due to the similar manner whereby their atoms are packed together in the crystal structures. On the other hand, no such relationships are observed between magnetite and haematite crystal in matrix. This suggests that haematite grains in the matrix may have been formed by other processes rather than those involved in the iron oxide transformation observed within the magnetite grains.

Jan 1, 2008

After four or so long years at university, where life revolves around lectures, assignments, and drinking coffee strong enough to keep you awake for five nights in a row to finish your thesis, preparing yourself for employment is not an ea

Jan 1, 1994

Following a summary of aerodynamic principles and the changes imposed by the process, areas important to the operator are then enumerated. These include furnace lines, cooling and casting technology, coke properties, gas distribution and others. Questions are raised on the implication of lowering the hearth substantially below the tuyeres and about the status of stack injection. Finally, the future developments are identified as being those associated with gas volumes required to pass through the furnace stack per unit time or per tonne of product.

Jan 1, 1975

Mine production planning and scheduling as a production planning problem can be handled using Linear (Goal) Programming. This approach is particularly useful when the product quality is important. This has been shown for many mine planning cas

Jan 1, 1998

Deformation of the lithosphere by tectonic forces is investigated from both observational and theoretical standpoints. Global and regional geophysical data bases, coupled with the means for their rapid display and analysis, facilitate recognition of areas of the con- tinents and oceans where the response of the lithosphere to these deforming processes might fruitfully be studied. Gravity anomalies, from Seasat altimeter data and from land and shipboard measurements, provide critical infor- mation on the isostatic state of deformed lithosphere and therefore on its thermal and mechanical properties.

Jan 1, 1987

In planning its production and investment activities the mining industry has generally paid too little attention to perceptive analysis of its market environment. The nature of world economic difficulties over the past decade is not a mystery. Essent- ially prolonged affluence has engendered a false sense of security and fostered entrenched vest- ed interests hostile to economic change. The overall outlook remains poor. For mining projects mineral demand affects both product prices and the availability of specific sales outlets. Long-term projection of demand is complex and a key to success is concentrating on analysis of fundamental deter- minants and avoiding mindless extrapolation.

Jan 1, 1983

By Moxon NT

The detonation pressure of ANFO can be significantly reduced by the addition of low density materials such as polystyrene, bagasse, sawdust or perlite. Laboratory and field test results have shown that homogene- ous mixtures of these low density explosives can be produced in a bowl truck and loaded into a blast hole without segregation. The detonation pressure of the mixture can be tailored to suit the material to be blasted by varying the quantity of low density additive incorporated into the mix- ture. Results obtained in the field indicate that these low density explo- sives can lead to significant cost savings without compromising fragmentation or production.

Jan 1, 1988

Effect of Hardwater on Selective Flocculation of Diasporic-Bauxite

Sep 13, 2010

The Broken Hill orebodies have 'traditionally been mined by cut and fill trethods. In the mid-1950's New Broken Hill Consolidated Limited experimented with sublevel longhole open stoping but did not pursue the method due to inefficient loading and poor fragmentation. The introduction of longhole open stoping in 1968 was a radical change and was necessary to enable the profitable extraction of lower grade orebodies and this method is now used for 55% of the production from The Zinc Corporation, Limited and New Broken Hill Consolidated Limited mines.

Jan 1, 1982

Perseverance Mine is a part of Leinster Nickel Operation (LNO), a fully owned division of Western Mining Corporation (WMC). The town of Leinster is located 370 kilometres north west of Kalgoorlie. LNO operates an underground gold mine and mill at Agnew, 30 kilometres west of the town in addition to two nickel mines and a mill 15 kilometres east of Leinster. Both the Perseverance and Rocky's Reward nickel orebodies are mined by open pit and underground methods.The Perseverance orebody was discovered in the early-1970s. Decline development commenced in 1977 and the first ore was milled in 1978. The shaft sink started in 1979. The shaft was comissioned in 1983, four years after sinking commenced. The mine was placed on care and maintenance in 1986 and purchased in January 1989 by WMC.

Jan 1, 1992

Seven papers have been reviewed and in this session. Broadly they can be grouped into three categories as follows: A Chemical Characterisation of Mine Waters Miller & Murray - Prediction of Time Dependent Factors in Acid Mine Drainage Jeffrey et. al. - Sulphide Oxidation in Pyritic Overburden; A Controlled Leach Column Study Sheridan et. al. - The Effect of Ore Type, Depth, and Leach Time on Cyanide Species in Column Tests using NaCN Leach Solutions B Mine Water Treatment Management Gilchrist & Hunt - The Recovery of Water from a Colloidally Stable Kimberlite Suspension Chapman, et. al. - Treatment and Utilisation of Hilton Mine Water

Jan 1, 1988

The role of marketing in the development of a new project will be affected by political, commercial and technical pressures. Marketing success will be determined by the ability to predict and react to tomorrow's environment. In the Australian coal industry there is an emerging transition from production to marketing orientation. As a result, greater technical awareness of customer needs will be required. In particular, the industrial product nature of coal markets will need to be recognised. Greater attention will also need to be paid to product options and quality in mine planning. Marketing personnel will become more involved at every phase of the development of a new mine.

Jan 1, 1983

By Brown P. L

A study has been made of the geochemistry of the Ronneburg mine district as input to the overall management strategy for the rehabilitation of the mine site. The study drew on the geological data and information store developed over the 40 years of mineral exploration and mining at Ronneburg, and on chemical data from the literature which described the chemical processes of weathering, oxidation, dissolution and precipitation of minerals. The geochemical processes were divided into three groups based on their rate of reaction. Fast processes were assumed to proceed to equilibrium and were modelled using equilibrium chemistry equations; slow processes were assumed to be proceeding at a quasi-steady state rate and were modelled using chemical rate equations; very slow processes were assumed to have no role in describing the geochemistry for rehabilitation purposes.

Jan 1, 1995

The Australian lead-zinc industry faces a future in which the world market is likely to show at best only minimal growth and in which there will be increasing competition. Its production facilities use mature technologies employing expensive labour and increasingly costly energy in a country which demands the highest standards of environmental performance. Returns on investment are already unsatisfactory.Technology for survival would appear to indicate a need not only for more efficient capital, labour and energy usage combined with improved environmental performance, but also flexibility to handle more complex materials than the traditional, virtually single metal concentrates. This offers the potential for improved overall economics from the mine onwards, but will demand efficient separation and by-product recovery processes.In the lead industry these problems are being addressed in several emerging technologies. With zinc, the situation is less clear.

Jan 1, 1985

Of the energy resources present in Australia, coal and uranium are by far the largest. These two resources ap- pear sufficient to satisfy Australia's energy needs beyond the immediately foreseeable future and long after the natural petroleum resources are exhausted or have ceased to play a significant role. By that time, coal could be converted in plants of very large size to synthetic liquid and gaseous fuels which will be used as substitutes for pet- roleum fuels, particularly for transport. The basic role of uranium will be to supply electricity from nuclear power stations for heat and power requirements, thereby freeing non-coking coal largely for conversion purposes. The establishment of these enterprises will require a massive national effort and a high degree of co-ordination at the planning stage.

Jan 1, 1975

The necessity for agreed project outcomes, which are in accordance with client needs, and the subsequent requirement for a unique approach to managing project implementation is discussed. Reasons for appointing a separate project team to manage a project are established. The selection of a project manager, based on the services they can provide and on their characteristics, skills and management style, is discussed. The consequences of selecting the wrong project manager are explored. A broad overview of the requirements for the project team is provided. Criteria for the selection of team members, and the role played by the project manager in this selection, are discussed. The levers that drive `on-time and on-budget' projects are discussed in terms of the project's vision, goals, controls, and incentives.

Jan 1, 1997