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Owing to the increased consumption of sulphuric acid; Australian manufacturers have, from time to time, been seeking for a satisfactory source of sulphur that would make them independent of foreign supplies.Some years ago a considerable amount of acid was obtained from the roasting of Spanish pyrites. This ore, in 1913 or thereabouts, cost 16s. per ton f.o.b. Huelva, and freight to the eastern seaboard of Australia was about 20s. per ton. As the ore contained 48% to 50% of available sulphur, it was costing roughly 9d. or 10d. per unit, and, in addition, the cinder, after roasting, was a product of considerable value to smelters, containing as it did a high percentage of iron suitable for fluxing, and appreciable values in silver and gold.

Jan 1, 1925

By J L. Mauk

Gladstone Hill, a volcanic-hosted low-sulfidation epithermal prospect in the Coromandel Peninsula, is less than 1 km from the world-class Martha Hill Au-Ag deposit. Gold-silver-bearing quartz veins occur in Late Miocene andesitic volcanic rocks of the Waipupu Formation that are extensively altered. The occurrence, spatial distribution and temporal relationships of hydrothermal minerals have been determined along two cross sections that transect the Amaranth, Gladstone, Cowshed and Moonlight veins. Quartz and pyrite are ubiquitous along these sections. Adularia and chlorite are widespread, but both are scarce in wall rocks adjacent to the Moonlight and Cowshed veins. By contrast, rare hydrothermal albite and epidote are restricted to wall rocks surrounding the Amaranth vein. Illite, which replaces adularia, is widespread and grades laterally eastwards into a zone of interstratified illite-smectite that envelops the Moonlight and Cowshed veins. During late-stage hydrothermal activity, rare calcite formed at depth and uncommon kaolinite and alunite formed at shallow levels. The overall clay mineral zonation with illite grading eastward into interstratified illite-smectite reflects paleothermal gradients of >220¦C to -170¦C towards the margin. The alteration assemblage of quartz, adularia, chlorite, albite, epidote, illite, interstratified illite-smectite and pyrite reflects formation from a near-neutral to weakly alkaline pH chloride water that contained low concentrations of CO2, Late calcite formed from very local descending steam-heated CO2rich water, whereas the rare assemblage of kaolinite and alunite formed from shallow steam-heated acid-sulfate water. Analysis of the available data indicates that the Martha Hill deposit and the Gladstone Hill area formed within a single large geothermal system. We infer that the Martha Hill deposit formed in the main upflow zone, whereas the Gladstone Hill area may have formed adjacent to this upflow zone.

Jan 1, 2001

By G B. Arehart, S J. Mathews, J L. Mauk

The banded nature of the quartz veins which form the Empire lode at the Golden Cross mine, is perhaps their most striking feature. Petrographic studies show that significant differences occur between the bands in terms of textures, quartz grain size, calcite, adularia and kaolinite content, and the form, concentration and mineralogy of sulfide phases.   The d18Oquartz values of individual bands within the vein material range from 7.3-10.9ë. Calculations show that the d18Oquartz values can be adequately explained by temporal variations in the system temperature, boiling and/or variations in the systems fluid/rock ratios.

Jan 1, 1995

Experimentally determined and theoretically explained phenomenon of zonal disintegration of rock around the development working brings about the radical changes in existing ideas about the mechanism of interaction rock massive with engineering constructions.The essence of the phenomenon consists in the fact, that forming of non-elastic deformations zone goes on by way of more intensive deformation and destruction of rock simultaneously in several zones, covering partially or fully output circuit and divided by zones of destructed rock. Under the influence of change of massive strained-deformational condition of depositional rock an accidental deviation of zones of supplementary expansion and compression of rock from the previous positions take place. One can observe multiplicational change of the outline, size and form of all disintegration zones in the time within the area of the working influence at massive. This phenomenon was named "fluctuation of zonal disintegration of sedimentary rock around development working".

Jan 1, 1991

The assistance that can be gained by the use of aerial photographs in the geological examination of a mineral field is clearly illustrated by the results of a rapid reconnaissance survey of the newly-discovered Mount Fitton talc, deposits, situated in the north-eastern extension of the Flinders Ranges in South Australia.The talc deposits were found to occur about the margins of a large lenticular mass of dolomitic marble, interbedded with hornfelsic tillites and fluvio-glacial sediments of Upper Pre-Cambrian age. Aerial photographs show clearly the extent of the dolomitic marble on which the growth of a species of eucalypt-Eucalyptus Gillei-is prominently developed, and which assists in defining the limits of this relatively light-coloured formation. (See Fig. 1).Upon field investigation it was found that the talc, deposits are related closely to the margin of the dolomitic marble where the latter has been subject to minor folding and faulting. The deposits themselves have been formed by metasomatic replacement of schistose dolomite. The contact of the dolomite with the underlying and overlying glacial beds is also noteworthy for the presence of minor occurrences of copper, silver, lead and zinc minerals.An examination of photographs covering a wide area reveals an outcrop of a massive granite to the north-east of the dolomitic marble, Fig. 2, which was almost certainly responsible for the regional metamorphism of the dolomitic and glacigene sediments, and the source of the mineralising solutions.All these features, as well as the broader structural features of the area, which are extremely important in the understanding of, individual commercial depQsits, were quickly determined with the assistance of the photographs.It is useful, briefly to relate the procedure adopted in examining this recently developed field as an example which may be well worth following on other fields, even if exposures are not so clearly defined. The method to be outlined, of course, will be of maximum advantage. Where rock exposures are good, where the ore bodies are likely to be widely spread, and where such bodies are related to some major geologi-cal control. Typical of such deposits are pegmatitic, hydrothermal and related ore bodies associated with the periphery of an igneous intrusion, or ore bodies related to particular sedimentary horizons in a regionally metamorphosed province.Procedure.The first requirement is the preparation of a detailed reconnaissance geological plan of as large segment as possible of the potentially mineralised province. The use of aerial photographs is par...

Jan 1, 1950

By L Olivier, R J. Lowther, J L. Lett, I Brunton

Hydraulic fracturing to precondition the orebody to enhance rock mass cavability is gaining acceptance in underground cave mining applications. Assisting cavability is becoming important as an increasing number of cave mines are being implemented in hard, deep and competent rock masses where clamping stresses are higher and cave column heights may be in excess of 1000 m. Propagating large caves to surface in such conditions can be challenging as risks such as slowed propagation and air gaps can develop during the process.Underground-based hydraulic fracturing is routinely used at Cadia East as a means of preconditioning the orebody to assist in cave propagation, fragmentation and seismicity reduction. This paper presents a summary of a surface-based hydraulic fracture program that was successfully implemented to assist in the propagation of the Cadia East Panel Cave 1 (CE-PC1) cave to surface through competent overlying rock masses. In this case study, the propagation of the CE-PC1 cave slowed as the cave grew past 750 m in height, initiating a Trigger Action Response Plan regarding the cave propagation rate. Surface-based hydraulic fracturing was subsequently used to stimulate the cave to propagate through the final 450 m to surface. The paper details the equipment, strategy, implementation and risk management involved in the program as well as the key learnings.CITATION:Lowther, R J, Olivier, L, Lett, J L and Brunton, I, 2016. Implementation of a surface-based hydraulic fracturing program to successfully propagate a large cave through hard, competent near-surface rock masses to achieve breakthrough, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 83–96 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By W. J. LANGRON

This paper describes the results of VLF-EM test surveys, using the Ronka EM-16 equipment, over a selection of environments in Australia and Papua.Using comparisons with known geology, drilling information and other geophysical work it is shown that the maximum depth of penetration of the method is about 100 ft but is considerably less than this in most areas.The author believes the method could aid in geological mapping and provide a useful adjunct to aeromagnetic surveying in some areas.

Jan 1, 1972

The sphere of operations of dry crushing has been so much enlarged of late years that the following notes with reference to its advantages and limitations, and also some practical results in connection with the crushing of gold ores will probably be of service to the members of the Institute. Until recently, with one notable exception that of the Mt. Morgan Gold Mine, dry crushing has only been practiced to a very limited extent in Australasia, and elsewhere it might be said to belong to industries other than mining Its sphere of usefulness depends on the fact that the' product is delivered in a dry state without the separation of the finer particles from the coarser to any appreciable extent, thus enabling the following advantages to be achieved with different ores.

By E Widzyk-Capehart

The mines of the future can be envisioned as complex, large-scale technological systems being operated remotely from few centrally located (major cities) operating centres and skeletal crew stationed at the site. These systems will require remotely located human operators to constantly adapt to new and unforeseen system and environmental demands. In addition, the remote operators will need to match system properties to the changing demands and operational conditions, ie must be able to handle the ‘non-design’ emergencies, because the system designers would not have been able to foresee all possible scenarios of failures and provide automatic safety devices for every contingency. Therefore, it is highly important that the operators’ job, which involves problem solving and decision making at the workstation level, is facilitated by the proper interface designs. This paper argues that decision support systems and thus human-system interfaces for the mines of the future should be developed based on the principles of human-system integration that take into account human information processing and cognitive abilities. The information presented to the operator must support the operator in taking appropriate action through a human-system interface designed according to scientific principles of User Centred Design. A case study is presented where an iterative design process was used by CSIRO researchers as an evaluation method involving users (control room operators) at several stages of the user interface design in order to correct any design inadequacies as they emerged. This process allowed the designers to identify any usability issues before the user interface was fully implemented, which subsequently enabled the control room operators to easily adapt to the new interface and carry out all designated tasks in a timely and effective manner.

Nov 22, 2011

The need to hoist increasing loads from great depths is leading to the more general adoption of winders of the Koepe and Blair types. The trend has introduced a number of new problems in winding ropes, more particularly in the Koepe system where regular destructive tests during the life of a rope are not possible. Consequently, the importance of introducing non-destructive tests is much greater, especially so in the case of Koepe ropes used for deep winding where there are three major destructive fatiguing influences. These are rotational effects when a vertical rope is changed end-for- end each trip, the much greater range of stress to which the rope is subjected each trip as compared with drum winding, and the destructive effect of a high coefficient of friction between wheel and rope. A plea for a lower coefficient in the interest of better rope and tread life, substantiated by analysis, is made for Koepe winders operating at depth.Co-ordination of rope testing with general hoisting problems is stressed and the active participation of the Wire Rope Committee of the Australian Mineral Industries Research Association Ltd. in the promotion ofthe project is noted.The general introduction of a rope testing programme in Australia, personnel requirements and some local basic research in the subject to cope with future demands are considered.

Jan 1, 1967

By Warren L. J

The effectiveness of shear-flocculation as a method for upgrading simple mixtures of ultrafine (1-11 \lm) scheelite and garnet was evaluated. Statistical methods were used in the design and analysis of the main test program.The stirrer speed, stirring time, and initial weight ratio were all found to have significant effects on both the recovery and grade of the floes produced. The particle sizes also had an effect on the final grade. There were several important interactions between factors which also affected the results. Optimum conditions for shear-flocculation were established, and under these conditions about 80 per cent of the scheelite could be recovered at a grade which depended on the composition of the starting mixture. Starting with mixtures containing 10 and 50 per cent scheelite, the best final grades were between 20 and 50 per cent and between 70 and 90 per cent respectively, the actual value depending on the particular combination of particle sizes.

Jan 1, 1977

The theme of this paper is the development of-the project feasibility study which includes discussion of the work which is carried out in preparing the project feasibility study, the necessary evaluations and structures that are employed to ensure that not only does the feasibility study itself stand up to scrutiny and is sound, but also that the investment the company is proposing to develop, "the project", is an investment decision which will represent good returns to the company. This theme is particularly relevant when there are competing divisions within the company and only limited cash resources are available to make the correct investment decision. Thus various potential investments may be evaluated against each other to determine which project will be given the go ahead for development. This paper will particularly focus on the various investment analysis techniques that are used and discuss the work that is required in preparing the project feasibility study and specifically the interaction of the project team members and the thought process that must be undertaken to complete the project feasibility study. Finally comments will be made on tax planning issues particularly with respect to taxation of gold production to be introduced in January 1991. Some ideas are presented which may help and possibly improve the financial position of the projects being reviewed. Further, it is suggested that the thought process which goes with the financial engineering aspects of a resource project can be widened to take account of taxation issues and tax planning to ensure the rise of the project feasibility and hence the decision to proceed to development by the project sponsors.

Jan 1, 1990

Thirty mixed cultures of microorganisms from soil, water and mineral samples from the Groote Eylandt Mining Company mine site were approximately three times more effective in biodegrading manganese dioxide (34± 18 mg Mn++/1/day) than sixteen purified strains (11 ± 10 mg Mn++/1/day) isolated from the primary enrichment cultures. Two pure bacterial genera identified as a Pseudomonad and a Bacillus, with an excess MnOz and nutrient, were able to dissolve 106 mg Mn++/litre/day in mixed culture compared with 29 mg Mn++/litre/day when grown separately.

Jan 1, 1983

The structure of the Bulli coal seam at Appin Colliery was detailed by the seismic reflection method. This unusual application of the seismic method was possible because there is a reflector near the seam as was revealed during exploration for petroleum in an area north-west of Appin. The reflector, which was at a depth of 1,500 ft, was shallow by normal reflection survey standards. Measurement of the seismic velocity at two ventilation shafts showed that the reflector was probably the Bulli coal seam. Accurate depth control was established from previous drilling results.INTRODUCTIONAppin Colliery, situated on the Southern Coalfield of N.S.W. (Fig. 1), is being developed to supply coking coal to the Port Kembla steelworks of Australian Iron and Steel Pty. Ltd. The colliery is mechanized and a detailed knowledge of structure, particularly faulting, is important in planning the workings.The Bulli seam, which is approximately 9 ft thick, and between 1,500 ft and 1,800 ft below the surface, is worked in the colliery. It is the uppermost member of the Permian Coal Measures and is overlain by Triassic rocks, which consist of thick sandstone beds containing beds of coloured shales, and which are subdivided into the Narrabeen Group, the Hawkesbury Sandstone, and the Wianamatta Group.In the early stages of development of the colliery, surface geological mapping and diamond drilling provided information on structure. Generalized results of the mapping are shown on Fig. 2. Drilling indicated that the physical and chemical properties of the Bulli seam are relatively constant, and that the seam is nearly horizontal, the average dipbeing about 1 in 25 to the west.

Jan 1, 1965

By D Flint, K Vague

The Work Health and Safety Act 2020 (WA) (WHS Act; DMIRS, 2020) and associated Work Health and Safety (Mines) Regulations 2022 (WA) (WHS Regulations; DMIRS, 2022), supporting guidance materials and other laws, such as the Sex Discrimination Act 1984 (Cth) (SD Act), have imposed new duties on every person or business conducting an undertaking (PCBU) in Western Australia, including those operating in the mining industry. These laws and associated guidance materials combine to require owners, operators and contractors to discharge positive duties and better report and manage psychosocial hazards in the workplace. For mine operators, there is a positive duty to not only identify and eliminate hazards relating to psychological harm, sexual harassment and gendered violence at work, but to also report incidents to the safety regulator that could result in serious harm, even while internal and police investigations are ongoing. Traditional mines safety teams are navigating the evolving frontier of psychological and gendered safety as the duties relating to psychosocial safety and sexual harassment at work continue to expand. This paper will review the legal obligations on PCBUs to conduct internal investigations into critical psychosocial incidents and gendered violence on mines, whilst balancing the demands and sensitivities of investigations by the safety regulator and police. There are emerging approaches to safety investigations that can aid PCBUs in managing their investigations of psychosocial incidents and gendered violence, including trauma-informed investigation techniques, collaboration with psychological experts and the use of limited legal privilege. Well managed and sensitive investigations can foster trust amongst workers, result in improved incident reporting by workers and lead to enhanced safety outcomes for the resources industry whilst preserving the legal positions of involved PCBUs. Specifically traversing the new duty to consult, cooperate and coordinate, this practical session will arm mine managers, safety professionals and human resources professionals, from mine operators and mining contractors alike, with tools and processes to bring to safety investigations, particularly on residential mine sites.

Apr 16, 2024

By S Reid, W Chen, T J. Donohue, A Katterfeld

The use of discrete element modelling (DEM) is widespread in the materials handling field, and is used for many applications. One of the important limitations in using DEM is the number of particles that can be modelled, with this limitation often resulting in increasing the minimum particle size in the simulation. This restriction on minimum particle size is usually accommodated in the calibration process where the parameters in the simulation are chosen in such a way as to reflect the presence of smaller sized particles, and in typical applications such as transfer chutes this is standard practice. However, in the application of vibrating screens the inclusion of the ‘fines’ is critically important due to their influence on the screening efficiency. In reality, the presence of fines reduces the screening efficiency for a number of reasons; however, the main mechanism that will be addressed in this study is the effect of adhering fines. This is where the fines adhere to the larger particles and are carried over into the lump stream. The approach for this study will be to firstly consider the relatively simple mechanical sieving process used in the determination of particle size distribution, and then this will be expanded to consider the application of vibrating screens.CITATION:Donohue, T J, Chen, W, Katterfeld, A and Reid, S, 2017. Addressing the challenges associated with the modelling of iron ore in vibrating screens, in Proceedings Iron Ore 2017, pp 155–160 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

The ore, as sent to the sulphide mill, is a mixture, in varying proportions, of oxidized ore from above the 450-ft. level and sulphide ore from above and below (to date mainly from above) that level. The oxidized ore consists essentially of quartz, with varying amounts of kaolin and clayey material which passes into the slime and, in excess, creates a serious problem in settling. Pyrite may be present in small amounts. The gold is free and extremely fine.The ore, classed as sulphide, consists of pyritic material in a quartz gangue. The sulphides have been exposed to weathering, leaching by descending solutions and attack by ascending gases and actual burning. The alteration products occur in widely varying proportions and this variation adds to the difficulties in settling and control of grinding and flotation.Copper Minerals.-Chalcopyrite is the principal copperbearing mineral with smaller and varying amounts of covellite, which is sometimes associated with chalcocite, both these minerals being apparently of secondary origin.Examination of tailing by Dr. Stillwell has revealed all stages between clean chalcopyrite, chalcopyrite tinged with covellite, covellite with residual cores of chalcopyrite and clean covellite.The chalcopyrite is free floating, very few particles of clean chalcopyrite being observed in the tailing from granular flotation. The chief tailing loss is probably as chalcopyrite occurring as small inclusions in pyrite...

Jan 1, 1939

By D Mnller, J L. Mauk

The Oblaga Cu-Au skarn deposit and porphyry prospect is located in the south-eastern edge of the Gobi Desert in western Inner Mongolia. The deposit occurs within metamorphosed middle Paleozoic volcanic, plutonic and sedimentary rocks.   Ivanhoe geologists recognise eight main rock types in the area. Calcareous sediments include conglomerate, interlayered siltstone-sandstone, and limestone. Covering the calcareous sediments is a slab of thrusted biotite granite, and above it is rhyodacitic lithic tuff which, in places, is overlain by alluvial sediments. Various plutonic rocks and related intrusion breccias have intruded these units. Monzodiorite, quartz-monzonite and monzonite tend to form thin, high-angle intrusions and the youngest andesitic intrusions are generally wider and subhorizontal.   The Oblaga Cu-Au skarn, which occurs in the calcareous sediments, shows typical prograde and retrograde mineralogy. Petrographic studies show that prograde skarn minerals have been overprinted by retrograde skarn minerals, and original host rock minerals have been texturally obliterated and completely replaced. The mineralogy of the Oblaga skarn deposit is very similar to other Cu-Au skarn deposits worldwide.   Sericitic and minor chloritic alteration occurs throughout the study area and may relate to porphyry-style mineralisation. Generally, this alteration is not intense and most rocks have retained their original texture. Geochemical analyses suggest that K-metasomatism is not widespread at Oblaga. XRD analyses suggest an upward and outward transition from sericitic to chloritic alteration.   Comparisons between Oblaga and other porphyry Cu-Au deposits worldwide show that Oblaga has very similar characteristics to deposits that have undergone sericitic alteration. However, Oblaga is special because it also has relatively intense chloritic alteration, which is uncommon in other porphyry Cu deposits described in the literature.

Jan 1, 2005

Recovery of Precious Metals from Chloride Solution by Magnetite The development of environmental-friendly lixiviants as alternatives to cyanide and the increasing recycling activities to recover precious metals from waste materials have prompted researchers to find efficient methods and alternative sorbents to recover precious metals, such as Au and Pt, from aqueous solutions. This study explored the use of magnetite (Fe3O4) as a sorbent to recover Au and Pt from chloride solutions. Magnetite is a semiconductor and has the capability of transferring electrons both within the solid state and across the solid-liquid interface and has the ability to reduce metal species on its surface. The sorption of AuCl4- and PtCl62- from NaCl solution on commercial grade magnetite powder was investigated by batch-sorption experiments. The effects of pH, contact time, NaCl concentration and precious metal concentration on the recovery were studied. Sorption experiments revealed that magnetite exhibited selectivity towards other metals with the strongest affinity for Au. Both Au and Pt recoveries showed similar pH dependence curves, with peaks at pH 6 - 7. At this pH range, a maximum of 4.4 ¦mol Au/g Fe3O4 and 3.0 ¦mol Pt/g Fe3O4 were recovered after 24 h at an initial metal concentration of 0.05 mol/m3. Increasing the initial precious metal concentration increased the Au and Pt uptake amount by magnetite. It was also observed that the recovery decreased with high NaCl concentrations. The SEM images of the magnetite particles after the treatment showed that gold, which was confirmed by the EDX analysis, agglomerated and were deposited on Fe3O4 surface.

Sep 13, 2010

Tyre costs constitute 20-40 per cent of the operating cost of large haulage trucks, and tyre pressure maintenance is an important factor in minimizing costs.In the past, control over the hot (built-up) pressures of earthmover tyres has been inaccurate and inconsistent because it has not been possible, in a practical way, to measure the tyre's contained air temperature.A method for measuring this contained air temperature has now been devised using a bi-metallic probe thermometer inserted through the valve stem. Using these measurements in conjunction with a pressuretemperaturechart drawn up using the general gas equation, very accurate control over hot tyre pressures is now possible.

Jan 1, 1979