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Broken Hill South Limited's discovery of phosphate deposits in the northwest of Queensland in 1966 prompted intensive exploration which has proved phosphate rock in excess of 2,000 million tons at ten separate deposits. Systematic exploration for phosphate in Australia was initiated by the Company in 1964. Early in 1966, an investigation of oil wells in the Georgina Basin in the Northern Territory and Queensland revealed widespread anomalous phosphate in early Middle Cambrian Beetle Creek Formation and Thorntonia Lime- stone. Phosphorites recognised in oil wells in the southeastern part of the Basin, Queensland, led to the discovery of the Duchess deposits, Exploration of the Beetle Creek Formation since 1966 has disclosed nine other sizeable deposits north of Duchess around the eastern margin of the Basin. The Lady Annie and the adjoining Lady Jane deposits, by reason of their location, 160 miles south of the Gulf of Carpentaria, are expected to be the first to be brought into production. Beneficiation testing and engineering investigations commenced in 1967. Transport between the deposits and various port sites in the Gulf of Carpentaria has been extensively studied and a slurry pipeline as a means of transport to a deep water island port, is now being investigated.

Jan 1, 1971

By G Corder

The aim of the circular economy is to accelerate the transition from a conventional linear take-make-dispose economic model to a circular model. It is restorative and regenerative by design and aims to keep products, components and materials at their highest utility and value at all times. This extended abstract presents a brief overview of the circular economy, provides application of the circular economy in other industrial sectors including the downstream metals value chain and proposes how circular economy thinking could progress the development of complex orebodies.CITATION: Corder, G, 2018. Can the concept of the circular economy help unlock complex orebodies?, in Proceedings Complex Orebodies Conference 2018, pp 8–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By Xizhen J

Point load testing for irregular rock specimens was studied to determine the relationship between tensile and compressive strengths, drill penetration rate and other rotary drilling parameters. The DH-l type point load tester was developed and more than 2 000 irregular specimens of over 60 kinds of rock from 16 mines and quarries were tested. The effects of size, shape and number of samples on the point load strength index were investigated, using regression analysis. Experiments were carried out to investigate the relationship between point load strength index and uniaxial compressive strength on 29 kinds of rock. The relationship between these values and the drill penetration rate for rotary and percussion drills is discussed.

Jan 1, 1986

By White A, Price G

The main assets of a mining company are its orebodies; the second are the people who find and use them.The graphs in Figure 1 were derived from a paper by Rob Macdonald of Rothschild Australia presented to The AusIMM Centenary Conference in Adelaide earlier this year. They show that the value of the industry on the Australian Stock Exchange halved over the past decade, despite the re-investment of capital equivalent to its full market capitalisation. Why is this so? The average dividend yields for the ASX Mining Index was never above five per cent during that period and barely averaged 2.5 per cent. Why then is $Ai million capital re-investment per employee since 1960 not enough to generate a rate of return to investors better than lousy bank interest? Do the investing public no longer regard our industry's assets to be world class?

Jan 1, 1993

By Fabjanczyk M. W

The design of underground mine roadways (tunnels) requires a detailed understanding of the in situ stressfield, the rock failure modes, the performance characteristics of reinforcement or support members and assessment of the stress state about the roadway. Definition of these factors, together with monitoring of roadway behaviour during both development and extraction operations, allows rational design procedures to be undertaken.The design approach utilised computational techniques to simulate the behaviour of the strata about the opening for a range of anticipated stressfields and various reinforcement options. Field validation studies are conducted to confirm the design expectations.

Jan 1, 1993

By Langberg D, Gray N. B

The flocculation of hydrophobic magnetite with gold was examined as a possible means of recovering fine (95 per cent were possible for 1.5 - 3.0 ¦m and 5.5 - 7.5 pm gold sizes. The effect of process variables on the flocculation process was explained by variations in the adhesive force between the gold and magnetite.

Jan 1, 1991

The recent installation of top gas temperature probes in blast furnaces at Australian Iron & Steel Pty. Ltd. - Port Kembla, has provided the means for studying radial gas flow distribution in blast furnace shafts. This paper describes the top gas temperature probes and outlines their development and results of initial studies aimed at obtaining a suitable relationships between temperature profiles and furnace parameters. The effects of various combinations of burden materials have been outlined by the results reported. The use of probes has also helped to clarify the effect of casting cycles on furnace operation leading to increased emphasis on the reduction of the interval between gun-up and drill-out. Areas for future studies are also broadly Outlined.

Jan 1, 1975

By G Corder

Even though most major operating companies in the minerals industry have Board-level endorsed sustainability principles and objectives, design engineers typically have no mechanism that allows them to implement those objectives in their work. In addition, the existing project management systems do not readily deliver the innovative solutions needed to address key sustainability issues, such as those related to significantly reduced carbon emissions, minimal environmental impacts, and maintaining the societal ‘licence to operate’. SUSOP® (SUStainable OPerations) is an approach for the integration of sustainable development principles into the design of mineral processes, which has been developed through the Co-operative Research Centre for Sustainable Resource Processing (CSRP). Somewhat analogous to the well entrenched HAZOP (Hazard and Operability) studies, SUSOP® is a holistic, systematic and rigorous mechanism for identifying and assessing sustainability opportunities and risks at each stage of project development - from corporate planning, through design and operation, to decommissioning and rehabilitation – without compromising financial rigour. SUSOP® was developed, tested and enhanced through its application to real case studies in the minerals industry. This development path provided significant insights into the process of identifying and evaluating opportunities for improving an operation’s contribution to sustainability and its long-term business case.This paper will discuss the need for a methodical approach for integrating sustainability principles into mineral processing plant design, present the key elements of SUSOP®, and outline its development path through real case studies. In addition, the reasons why such an approach will have growing importance into the future will be raised.

Aug 8, 2011

By Horowitz F. G, Lamb P

As mining operations become larger and more complex, larger volumes of geological, geophysical, and production data must be manipulated and interpreted on a day-to-day basis. Because of the large volume of data, more sophisticated data storage strategies, interpretation tools, and visualisation tools must be used by exploration and mining operations in order to remain competitive. Critical to better practice is an understanding of the basic syntax and character of geological and mining data, expressed in the form of a data model. In the short-term, a data model can be used to implement or evaluate schemes for data storage or exchange. It can be used to evaluate software. In the longer term, a data model is essential to the design of the next generation of software for 3D geological modelling. In this and the related paper (Lin et al, 1995) the data model in use by CSIRO is presented, together with: 1. examples of the use of data transfer in the linkage of existing mining software; and 2. examples of the use of the data model in software design.

Jan 1, 1995

By P Albert, S Crispin, J Hertrijana

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Martabe gold mine is Indonesia’s largest precious metals-only producer and is also one of few significant hard rock mine developments in the past 15 years. Martabe is located on the west coast of the island of Sumatra in the North Sumatra province. The mine commenced operation in mid-2012, producing over 280 koz of gold and 1.5 Moz of silver in its first full year of production.Martabe consists of a cluster of six currently identified high-sulfidation epithermal deposits. The deposits lie in a north–south corridor with an approximately 8 km strike length and 1.5 km width. The total Measured, Indicated and Inferred Mineral Resource Estimate of the deposits is currently 8.2 Moz of gold and over 75 Moz of silver.The exploration program at Martabe has added more than 2 Moz of gold and 15 Moz of silver to the Mineral Resource estimates (Measured, Indicated and Inferred categories) since G-Resources acquired the project in 2009. This has been achieved at an average cost of US$17 in exploration expenditure per ounce of resource added, which includes helicopter-supported drilling programs in rugged forest terrain.The factors that led to this exploration success at Martabe include: in the first instance and most importantly, recognition of the geological potential of the mineralised system continually updating and improving ‘orebody knowledge’ and applying new ideas to the exploration program ongoing engagement and consultation by world professionals with geological expertise in similar systems ongoing executive management support for the program the high quality of work completed by previous owners a strong focus on quality control, staff development and operational safety, with the JORC Code (in particular Table 1 of the Code) as the underlying basis for quality control continual and positive engagement with government, community and other external stakeholders.This paper will discuss in detail the first of these two factors. It is important for the modern exploration team to recognise that mineral potential on its own is not sufficient for exploration success, so this paper will touch on the other factors as secondary but crucial considerations.CITATION:Crispin, S, Hertrijana, J and Albert, P, 2015. Exploration success at the Martabe gold mine, Indonesia, in Proceedings PACRIM 2015 Congress, pp 567–572 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Rowe P, Rogers D, Warren M

Pressure cyanidation of the minus 10 micron slimes fraction of the Fimiston flotation concentrates for the recovery of gold values has been evaluated as an alternative processing route to the roasting and atmospheric cyanide leaching of the calcine. Laboratory and pilot trials have demonstrated that gold extractions of greater than 94 per cent can be achieved at cyanide consumptions of 12-24 kg/t and oxygen consumptions of 0.1-0.3 Nm3/t with total pressures of 1000-2000 kPa. Economic and operational assessment of several reactor configurations suggests autoclaves may be preferred over pipe reactors at treatment rates of 10 t concentrate/h.

Jan 1, 1996

By J Bang, I-H Jung

Ti is an important constituent for steels and superalloys. During the continuous casting process and ElectroSlag Remelting process (ESR), Ti in molten steel and superalloy can have chemical reactions with casting flux and ESR slag containing CaO and CaF2. In order to investigate such exchange reactions, the understanding of the (Ca,Ti//O,F) reciprocal slag system is prerequisite. In the present study, a coupled phase diagram experiment and thermodynamic modelling of the (Ca,Ti//O,F) reciprocal system was performed. In particular, the phase diagram of the CaF2-TiO2 system was experimentally investigated by Differential Thermal Analysis (DTA) experiment and quenching experiments followed by Electron Probe MicroAnalysis (EPMA) phase analysis. The Gibbs energy functions of all solid and liquid phases in the (Ca,Ti//O,F) reciprocal system were optimised to reproduce the present data and all available reliable experimental data in literature.

Jun 19, 2024

By Frith RT, M D. Goodz

Drilling has been accepted as a major exploration tool. However its use in mine planning and development has been overlooked.This need for drillhole data was highlighted during the redevelopment boom of the central Victorian gold mines. During the 1980's numerous old mines were evaluated and successfully drilled to yield mineable parcels of quartz reefs close to existing workings.Invariably the initial decision was always to attempt reopening and rehabilitating existing access. The four case studies described have proceededsufficiently to show that major cost savings would have been made if underground drilling had been used as the main tool in mine planning.Savings not only in expenditure, but in the time required to make key decisions. In two cases the mines would have experienced far earlier expansions in production. In one case the mine would be currently producing rather than awaiting further finance. In the fourth example, the decision to case development would have been much earlier providing capital to other projects.

Jan 1, 1990

By E Gabriel, J C. Koppe, A Gomes and P Crispim, R Schaarsdmit, I Pablos

Drill and blast (D&B) is one of the most important production operations in open pit mining. The resulting fragmentation of the D&B reflects in the downstream unit operation. Good fragmentation of the ore will minimise the cost of loading, hauling and crushing. The understanding of the geological model integrated with a software system for bench face surveying and planning of blast layouts based on three-dimensional images can help to achieve the fragmentation goals of the mine operation. A case study integrating these tools was carried out in a large iron mine in Brazil. The iron ore in the study area consists of hard and friable itabirites. More than three different ore types may occur on the same bench. Under these conditions, data integration becomes necessary to improve the results of blasting. A blasting plan was based on the generated geological model. The methodology helps understanding the factors that can interfere in the fragmentation process, allowing defining actions that can improve the blast design in those places that fragmentation wasn’t achieved. This condition is important for a continuous improvement of the drilling and blasting operation. In comparison with the previous blasting carried out at Itabira mine, which did not take into account the geological model, substantial improvements in fragmentation were observed, eliminating the need for secondary blasting.CITATION:Schaarsdmit, R, Pablos, I, Koppe, J C, Gabriel, E, Gomes, A and Crispim, P, 2015. Geological modelling and bench face survey to improve blasting fragmentation, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 401–406 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By M M. Pande, M Ishfaq

The effect of aluminium on nitrogen solubility was investigated by equilibrating melt comprising master alloy of Fe-Al with pure electrolytic iron in a controlled atmosphere (pure argon) at 1873 K. Nitrogen in the samples was measured by sampling technique using inert gas fusion absorptiometry. It was found that nitrogen content decreases steadily with aluminium concentration and gradually, becomes close to 1 ppm for very high aluminium steels. Wagner’s second order interaction parameter formalism has been used to estimate the equilibrium constant and interaction parameters. Scanning electron microscopy (SEM) investigation showed, dual-phase inclusions comprising AlN phase surrounding alumina core. The 3D morphology of inclusions was studied by extracting the sample from the top and the central bottom portion of the solidified ingot. A sparse distribution of nitrogen was found for most of the inclusions which manifested the presence of almost pure alumina inclusions with different morphologies and sizes.

Jun 19, 2024

By Waters JC

Pseudoclastic hydrothermal alteration textures occur within quenched coherent dykes forming part of a subaqueous dome complex (-4 Ma) on Ponza Island, Italy. These textures are similar to those observed in considerably older (-500 Ma) subaqueous volcanic rocks at a number of localities throughout the Mount Read Volcanics in Tasmania and elsewhere in ancient volcanic sequences of this type in Australia. This is significant because the processes of formation, hydrothermal alteration and secondary mineralisation of ancient volcanic sequences may be better understood if we can make comparisons with modern analogues. Observations at Ponza imply that these pseudoclastic alteration features form synvolcanically or immediately after dyke emplacement and lava extrusion. This is compatible with scenarios presented for their formation in ancient sequences in the Mount Read Volcanics, Tasmania.

Jan 1, 1995

By S Meffre, S Golding, K Zaw, J McPhie, R James, S Suphananthi

The Chatree deposit is located in the central portion of Loei Fold Belt, which extends from Lao PDR in the north through centralThailand to Cambodia in the south. Epithermal gold-silver mineralisation at Chatree occurs as veins/veinlets and stockworks with minor breccia in volcaniclastic and volcano-sedimentary rocks of andesitic to basaltic andesite composition and Permo-Triassic age. This preliminary oxygen isotope study mainly focuses on vein quartz of Au-Ag bearing mineralization (Stage 2) and a few samples of late Stage 4 quartz ¦ calcite veins. Quartz from Au-Ag bearing mineralisation has oxygen isotope values ranging from 8.1 to 12.3ë with the lowest values generally occurring at the deeper level (140 m below the surface). The late barren quartz ¦ calcite veins (Stage 4) tend to have higher oxygen isotope values ranging from 11.9 to 12.0ë. The oxygen isotope composition of the Chatree ore fluids were calculated at 250¦C, 300¦C and 350¦C based on homogenisation temperatures of fluid inclusions. The calculated oxygen isotopic composition of the Chatree ore fluid ranges between -1 and 6ë that overlaps with both meteoric and magmatic compositions. This shift in oxygen isotope compositions may relate to processes such as water rock-interaction and/or mixing of meteoric and magmatic fluids. It is interesting to note that the lowest quartz oxygen isotope values are spatially more or less confined to the prominent structures in the centre of the major ore zones. These structures may have been acted as conduits for higher temperature magmatic fluids. The quartz oxygen isotope values increase outwards from the centre of the main ore zones to the margin of the pits possibly due to mixing of magmatic fluids with lower temperature meteoric water. Whole rock oxygen and hydrogen isotope studies are in progress to investigate isotopic trends in the wall rock away from the ore zone. The systematic variation of oxygen isotopes in quartz from the mineralised veins and adjacent wall rocks could potentially be used as a vector to ore. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Hall C. E, Chrisholm J. M

Resource calculations for shear hosted deposits of any type are difficult regardless of which calculation technique is used. One of the main problems is the determination of the geometry of the mineralisation. Once this has been elucidated then the appropriate resource calculation methodology can be employed with a search distance and orientation that is relevant.

Jan 1, 1993

By D A. Sketchley

The Merlin Zone, a 2008 high-grade Mo-Re discovery, is a part of the Mount Dore Deposit in the Eastern Succession of the Mount Isa Inlier in Queensland, Australia. Hosted by carbonaceous metapelites and phyllites, the Merlin mineralisation comprises molybdenite veins, breccia infillings, stylolitic fracture fillings, and disseminations. Because rhenium is geochemically similar to molybdenum and commonly associated with it, global production of rhenium has been mostly a by-product of molybdenum refining. The high-grade rhenium in the Merlin Zone is an exciting discovery that is expected to become a direct source of rhenium. At the time of discovery, quality assurance (QA) procedures for rhenium were not in place at the Merlin Zone; therefore, they needed to be developed.The Merlin Zone was discovered using reverse circulation drilling, which led to concerns about molybdenite loss due to poor sample recovery. The twinning of the discovery hole with diamond core demonstrated a two-fold increase in molybdenum grade over several tens of metres. Consequently, the resources of the Merlin Zone were defined using assays from diamond drill core.Early analytical work, which was initially done only for molybdenum, comprised geochemical analysis with an aqua regia digestion, which have poor precision and can be biased low. Although initial testing for rhenium used similar procedures to those for molybdenum, a scarcity of commercial rhenium reference materials led to a validation process using neutron activation analyses and different digestions. This resulted in introduction of four-acid digestion assays, development of matrix-matched reference materials, and improvements to the quality of molybdenum and rhenium assays for reporting resources. Coarse and pulp duplicates were used to check for sampling bias and to ensure that levels of precision were adequate for the style of mineralisation and analytical methods. In addition, the direct and consistent geochemical correlation between molybdenum and rhenium provided another method for checking analyses.

Aug 22, 2011

By E R. Ramanaidou

Two unknown iron ore samples were found by a geologist from Ok Tedi Mining Limited copper, gold and silver mine at an old wharf site dedicated to a 1970s drilling program in Lake Murray in Papua New Guinea (PNG). These iron ore samples could not come from a PNG mine and it was decided that a study should be undertaken to understand their origin. Lake Murray is the largest lake in PNG with a total surface area of 647 km2. It has a high-water 2038 km long convoluted shoreline with seasonal water level changes (Osborne, Kyle and Abramski, 1987) and it is located around 200 km south of the Ok Tedi mine (5°13’25”S, 141°09’37”E). The petrology, mineralogy and chemistry of two Fe samples (Ok Tedi 1 and Ok Tedi 2) included optical microscopy, X-ray fluorescence (XRF) analysis and a comparison with worldwide iron ore deposits. The two rock samples were cut to produce two subsamples: (1) a polished thin section; and (2) a pulp that was used for XRF analysis including major, minor and trace elements. Ok Tedi 1 and Ok Tedi 2 were petrologically and chemically compared to a range of known iron ore samples from Australia, Brazil and South Africa. The petrological study of Ok Tedi 1 indicates that it is composed of granoblastic recrystallised hematite and the overall texture is uniform without any obvious original ‘sedimentary’ texture. Ok Tedi 2 is a ‘specular’ or platy hematite with recrystallised and fused grains. Using both petrological and chemical clues, the two Ok Tedi samples likely originated from the Iron Quadrangle in Brazil.

Sep 18, 2023