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By Carroll D. A

The mining and minerals industry has had and will undoubtedly continue to have a considerable impact on the development of this State. For the first 60 years of its history the colony of Western Australia made slow progress; its population in 1889 being only 43,000. However, as a-result of discovering gold at Coolgardie and Kalgoorlie the Eastern Goldfields alone had a population of 25,000 by 1897. The income generated by the gold mining industry allowed the Premier of the day, Sir John Forrest, and his Government to support the proposal put forward by the State's Engineer in Chief, C.Y. O'Connor, to construct a pipeline to carry water from the Darling Ranges to Kalgoorlie ; a distance of 600 kilometres. The demand for people knowledgeable in the science and art of mineral exploitation also prompted the State Government to establish a School of Mines in the Goldfields in 1902, where it has remained ever since. The gold mines of this region have been a major source of employment for over 70 years and there is no doubt of the fact that their continued prosperity minimised the effect of the world recession on Western Australia in the 1930's.

Jan 1, 1979

An Investigation on the Effect of Chrysotile Particle Shape and Anisotropic Properites on the Rheology of Chrysotile Suspensions Chrysotile, a polymorph of serpentine, is a phyllosilicate mineral that occurs as a major gangue mineral in many ores (eg Mt Keith nickel sulfide ore, Western Australia). The rheological behaviour of chrysotile stems from two main factors: its distinctive morphology and its electrical surface charge. It is believed that these factors are central to the problematic rheological behaviour and low solids throughput typically experienced in the processing of such ores. In this work, a study of the effects of chrysotile surface charge properties and particle shape on the rheology of chrysotile suspensions was conducted. It was found that the rheology of suspensions of pure chrysotile is characterised by extremely high yield stress values over a broad pH range (pH 4 to 11).The disparity in the point of zero charge and range of maximum yield stress for chrysotile is consistent with the anisotropic nature of chrysotile particles. A comparison of the rheological behaviour of quartz suspensions (non-fibrous) to that of chrysotile suspensions (fibrous) provides a practical indication of the effects of the fibrous nature of chrysotile relative to non-fibrous minerals. The long, thin fibres are easily entangled to form suspensions with much higher plastic viscosities and Bingham yield stresses than non-fibrous particles. Chrysotile particle shape and surface charge are central to the rheology of chrysotile suspensions, although shape appears to play a more significant role in this regard. This fundamental study would be beneficial to the ongoing research for improved recovery in the Mt Keith nickel sulfide ore as well as other chrysotile bearing ores.

Sep 13, 2010

An attempt has been made in tftis paper to review the general situation regarding the needs of the Mining and Minerals Industry for skilled and qualified personnel. Having defined the behavioural objectives of the courses of study, reference is thereafter made to the factors influencing the effective design of courses for apprentices, technicians and Technologists.

Jan 1, 1981

By Davidson JR, Napier-Munn TJ, Kojovic T

A research program was conducted to determine the relationship between operating conditions and medium losses in Mt Newman Mining's Beneficiation Plant. It was found that major medium losses were adherence losses and losses fran the overflow from the water recovery cyclones. Operating density and medium blend were found to have a significant effect on the medium consumption. Viscosity was thought to be the underlying factor. This viscosity problem was overcame by adding dilution water to the cyclone spigot discharge to reduce viscosity. The result was a reduction in medium consumption of 25 percent under normal operating conditions. Keywords:- Heavy Medium, Viscosity, Medium Carposition

Jan 1, 1987

The various risk components to be addressed by explorers and project developers (and their investors) to minimise and/or manage the risk of Pacrim mineral investment are summarised to provide an overview of the issues involved and to set the scene. It then highlights the role of individual Mineral Industry Professionals (especially independent consultants) who are at the heart of any risk reduction or risk management strategy. The involvement of accredited qualified/experienced (competent) and reputable professionals is essential to produce realistic and reliable results that gain and maintain investor confidence. Today, high ethical standards as well as technical competence are sought by government legislation/licensing regimes and initiatives of professional bodies like AusIMM, MICA, Professions Australia, Council of Professions, etc. All attempt to regulate and guarantee reputable individual professional behaviour (particularly in the context of currently perceived high corruption levels in many Pacrim countries). Brief comment will discuss the usefulness of accreditation and ethics codes plus other specific codes (eg JORC/VALMIN and their international analogues in Canada, South Africa, etc) in reducing risks.

Jan 1, 2004

By D Bradshaw

The recovery of molybdenum at Kennecott Utah Copper (KUC) has become increasingly important as its demand and price have risen dramatically in the last few years. Consequently, the flotation behaviour of the molybdenum bearing mineral, molybdenite, has received a significant amount of attention. The flotation performance of molybdenite generally lags that of the copper sulfide minerals and is much more variable. There are many factors including particle size, liberation, surface slimes and oxidation that contribute to this and also much speculation as to the relative contribution of each of these factors. This paper discusses the morphology of the molybdenite found at KUC, the mineral associations in the different lithogical ores types and the effect that each of these has on flotation performance. Quantitative mineralogical analysis and an assessment of particle shapes are used to explain that flotation behaviour does not necessarily follow expected trends and that some behaviour is counter-intuitive. This unique behaviour can be explained by the morphology and anisotropic nature of molybdenite.

Jan 1, 2008

By Pirvics AI, Whitworth NR, Tuppurainen JMI

Process control applications to the unit operations in both the Lead and Copper Smelters are reviewed. The basic aim of this control is to smooth plant inputs to produce an output of consistent quality in terms of chemical composition, temperature and physical properties. Most effort has been put into the process bottlenecks, namely in the process baghouse of the Lead Smelter and in the Copper Smelter reverberatory furnaces. The method of approach is discussed, firstly extensive plant measurement and data logging plus identification of factors which most affect the unit operation and secondly control of these factors to smooth out variations. This has been possible due to the development in-house of on-line instruments to measure the critical variables and the external use of computers for plant control. Some of these instrument developments are also briefly discussed.

Jan 1, 1984

A geologic, petrographic and geochemical study has been performed on the pyroclastic flow deposits in the coastal area of East Zhejiang Province, Southeast China. This study leads to classification of the pyroclastic flow deposits into three associations: the extrusive type, the surge type and the ash flow type welded tuff associations. Through detailed investigation and comparison of the characteristics of these lithologic associations, with emphasis on the welded tuffs, a comprehensive model has been proposed to demonstrate the petrogenesis of the pyroclastic flow deposits.

Jan 1, 1995

In this paper presented are the criteria used when assessing the harmfulness of shocks affecting the buildings. Those criteria are based on the value of speed or accelerations of building vibrations. Presented is the scale of harmfulness of vibrations of Langefors and Kihlstrom, Bureau of Mines, and SWD contained in the Polish Norm PN-85/B-02170. The parameters of the mining shocks measured by the Lubin coal mine station were compared with the parameters calculated as per the correlations (regression curves). The average acceleration calculated from the correlations for eight measurements is only two per cent higher than the actual one. But the average frequency of vibrations calculated from the correlations for eight measurements is as much as 2.22 times lower than the actual one. In order to analyse whether that takes place in the whole range of the energy of shocks compared were the results of calculations from the correlations for various magnitudes of shocks and various distances from their epicentre with the results of the measurements. From that it follows that only for the shocks of the highest energies the lowering of the frequency of vibrations by two times causes movement from the higher zone of harmfulness to the lower one (for example from the IV to III). In the one-family houses in Lubin there were the damages that are characteristic for not only for the III but also for the IV sphere of harmfulness as per the SWD scale. That should be explained via further research and maybe it would be feasible to draw out a new correlation to determine the frequencies only for high values of energy of shocks and determine the preciseness of the acceleration and frequency correlations used presently.

Jan 1, 2003

A magnetometer survey 'was the Darkes Forest area between 1968. The instrument used was model MZ4 with sensitivity 9.4 conducted over part of 30th April and 3rd May, an ABEM torsion magnetometer gammas per scale division. The survey consisted of a closed magnetometer loop along lines cut for a previous magnetometer and seismic reflection survey by Wongela Geophysical in March, 1968. The magnetic results of the previous survey were not satisfactory in some areas and are presented as a comparison in instrumentation. Station separation in the present survey was 100 feet with tie-in readings at shot points of the previous survey (usually 1320 feet apart)

Jan 1, 1969

By J Kleynhans, D Vermeulen, V Cogho

A number of rehabilitated open cast coalmines in SA are already decanting. The paper focuses on the situation at one of these mines where the following information exist: monthly decant rates and rainfall; sulfate concentrations of the decanting water; water level measurements inside the mine prior to decanting; ABA analyses; information about the rehabilitation (drainage slope, vegetation, soil used). A 2D-model was constructed for the mine and calibrated against six years of flow data. About 85 per cent of the decant outflow rate comes from direct recharge on top of the rehabilitated mine while the other 15 per cent is derived from lateral groundwater inflows. The estimated recharge value was 17 per cent of the rainfall. Measured sulfate values showed that the sulfate generation rate for the mine was in the order of 7 kg/ha/d. Conclusions from the study are:most of the water decanting from rehabilitated open cast coal mines is derived from recharge via rainfall; given a specific sulfate generation rate, then: the lower the recharge the less the decant rate but the higher the sulfate concentration of the decanting water and vice versa; future prediction of the decant rate must be stochastic according to expected percentile monthly rainfall values; and as a first assessment of the predicted sulfate concentration of decant water from rehabilitated open case mines, the 7 kg/ha/d sulfate generation rate can be used.

Jan 1, 2003

By Michot LJ, Kongolo M, De Donato PH

Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS), Hallimond tube flotation tests and microelectrophoresis measurements have been used to investigate the reactions involved in the adsorption-ion of K-amyl xanthate on finely ground pyrite. Pure pyrite was finely wet ground, at different pH values, in specially built laboratory stainless steel or iron rod mills. Amyl dixanthogen was the only product identified on the surface of pyrite when stainless steel rods were used. When iron rods were utilised, ferric xanthate and physically adsorbed xanthate ions were observed in the superficial phase. The use of iron media was found to depress slightly the floatability of the mineral.

Jan 1, 1993

By M Hitzman, E P. Nelson, J Skarmeta

The Coastal Cordillera of northern Chile hosts the youngest and possibly best preserved iron oxide copper gold (IOCG) belt yet discovered and includes important deposits such as Candelaria and Mantoverde. The spatial and temporal relationships of hydrothermal alteration and mineralisation (Fe and Cu-Au) related to structural and lithologic features were investigated through geologic mapping and petrographic and geochronological studies along two W-E-transects crossing the Coastal Cordillera to the north of Vallenar. The project aimed to determine vectors for district-scale and regional exploration. Along with magnetite-apatite deposits (Central Iron Belt) and manto-type copper deposits, the IOCG deposits are hosted in a N-trending volcano-sedimentary sequence formed in a Jurassic to Early Cretaceous arc/back-arc setting (Sillitoe, 2003; Ramos and Alemßn, 2000). Calc-alkaline plutonic rocks intrude and metamorphose the volcano-sedimentary sequence, and become progressively younger from west to east reflecting a shift of arc magmatism (to Paleocene in the far east). From west to east along the Agua Grande-Chehueque profile, four domains of different economic potential are recognised. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By I Warren, M P. Simpson

Adularia-sericite epithermal ore deposits have well-documented alteration mineral zonation patterns with distinctive geochemical signatures. Proper use of whole-rock geochemistry can provide useful vectors for exploration and can enhance efforts to characterise and quantify the mineralogy and intensity of hydrothermal alteration.   Analyses of Au and Ag provide the most direct vectors to orebodies, and pathfinder elements such as As, Sb, Hg, Zn, Pb and Se are similarly zoned around at least some orebodies. However, the minerals that contain these elements occur almost exclusively in veins, and therefore identifying geochemical vectors related to wallrock alteration that is zoned outward from orebodies is crucial for effective exploration.   Distal alteration zones contain quartz-illite-chlorite-carbonate-pyrite, whereas samples proximal to veins contain quartz-adularia-pyrite, with lesser though variable illite-chlorite-carbonate. Therefore, adularia-sericite epithermal ore deposits show K alteration in their cores. The resulting K-metasomatism can be evaluated in several ways. Areas that have been most intensely altered are commonly characterised by highest K contents, but these results can be complicated by variations in rock type across the prospective area. Potassium mass balance results provide a robust and rigorous assessment of K-metasomatism, however, knowledge about the composition of fresh rocks and correct identification of fresh precursor compositions of altered rocks are required. Three alteration indices provide effective evaluation of K-metasomatism: 1.   the K number, which is the ratio K/(2Ca+K+Na) (molar); 2.   Barrie values [(K2O * 100) / Sr]; and 3.   the Rb/Sr ratio. In most places these provide similar vectors, although K numbers can be complicated by the appearance of hydrothermal calcite and/or albite.   Plots of K/Al vs (2 Ca + K + Na)/Al (molar) allow estimation of the intensity of K-metasomatism and its mineralogical products, thereby complementing traditional XRD and petrographic studies of alteration minerals.

Jan 1, 2005

At depths greater than several kilometres in the crust, elevated temperature, confining pressure, and the presence of reactive pore fluids typically drives rapid destruction of permeability in fractured and porous rock. Ongoing deformation is required to regenerate permeability and facilitate the high fluid flux necessary to produce hydrothermal ore systems. A dominant influence on the evolution of fluid pathways in hydrothermal systems is provided by stress states, fluid pressures and reactions that drive permeability enhancement and compete with permeability destruction processes (Cox, Braun and Knackstedt, 2001). An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By J K. de Wet, G Balassone, J D. Singleton, V Arseneau

The Accha-Yanque zinc belt in southernPeru is a major zinc-lead rich metallogenic province. In the belt are comprised several non-sulfide-type occurrences, extending on the periphery of the Yauri-Apurfmac batholith (Oligocene-Miocene). Zinc mineralisation at Accha (almost fully oxidised) occurs in breccias of sedimentary and tectonic origin in the limestone of the Ferrobamba Fm (Middle to Upper Cretaceous). Non-sulfide association consists mainly of smithsonite and hemimorphite replacing both primary ore minerals and carbonate host rocks. Mn(hydr)oxides and Zn-clays (sauconite), can be locally very abundant. Differences in mineralogy of the ore and gangue minerals, as well as the composition of the host rock can have a profound impact on zinc recovery and reagent consumption, and therefore on the economic value of the deposit. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

According to the Australian Bureau of Statistics, fatalities from road transport accidents represented an average of over 97 per cent of all transport related accidents between 1997 and 2002. With increasing traffic density, tunnels are becoming a more viable means of providing alternative travel routes to ease areas of congestion in the road transport network. However, unlike open road conditions, a fire incident in the confined space of a tunnel environment may impact upon many users that are remote from the incident location. In this context, designing for an appropriate level of safety in tunnels is therefore an important consideration for achieving consistency in the life safety measures for users of the road transport network. Unfortunately, like fire safety engineering design for buildings, there are presently no clear measures in the design processes to assess the adequacy of the design in terms of attaining the level of safety implicated in the design objectives. This is partly due to the indeterminate nature in which the design objective or the level of performance measure is stated û the intent of the objective is relatively clear but the measure of it is not. Another reason is the lack of a standardised procedure for determining the critical design variables affecting life safety. This is important to ascertain consistency in the use or adoption of the important parameters for design. This paper looks at the processes involved in the fire engineering design of road tunnels that are currently practised. A review of the design processes for fire safety in road tunnels is provided, which includes the range of fire scenarios in a tunnel environment, the traffic flow and composition, the relevant fire protection systems, the ventilation and smoke control system, the egress provisions and the benefits of incorporating fire brigade intervention. A simplified risk assessment approach is developed for a typical road tunnel to assess and evaluate the impact of a range of design parameters on life safety. Using a sensitivity technique, the important variables are then identified and means of reducing design variations associated with them are recommended. The technique may be further refined for use in the development of codes or guidelines in order to develop a suitable means of deriving more consistent design values, and hence achieve better consistency in the overall level of safety in the design.

Jan 1, 2008

By Matthew I. G, Hall P. G

The Selective Precipitation (Basics) Process is a means of controlling impurities such as the ions of Mn, Mg, and Cl as well as sulphate and water, in an electrolytic zinc plant circuit. This is achieved by precipita- ting zinc selectively as a basic zinc sulphate from a portion of impure circuit solution. The impurities remain in the solution, which can be discarded, while the zinc, substantially free of impurities, is returned to the main circuit by using the precipitate as a neutral- ising reagent. A description of the process and its development to a full scale operating plant at the Risdon Works of the Electrolytic Zinc Company of Australasia Limited is Presented.

Jan 1, 1977

Study on the Recovery of Zinc Minerals from the Tailing of a Lead and Zinc Mineral Processing Plant

Sep 13, 2010

The Rehabilitation of Acid Mine Effluents and Toxic Heavy Metal Pollution, Emanating from Gold Mines in South Africa

Sep 13, 2010