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The Devonian Mount Morgan gold-copper deposit was situated on the western margin of the Calliope Volcanic Are assemblage, in the northern New England Orogen. Recorded production from commencement of mining in 1882 to mine closure in 1989 stand

Jan 1, 1994

Over the past 12 years screening of materials has undergone a dramatic change in both the types and materials used in screen mats and the quality requirements of the finished product. With the main thrust now on quality and a cleaner product a different approach was needed in the operation of sizing screens. New screen mats with many different aperture configurations have been developed using rubber and plastics.to replace the traditional screen mat of woven wire or punched plate.

Jan 1, 1984

By R L. Koenig

The rediscovery and recognition of the magnetite potential of the iron mineralisation at the Hawsons Project area 60 km south of Broken Hill has the potential for the development of a new series of magnetite iron-ore operations across the Braemar Iron Formation in New South Wales and South Australia. Despite the low-grade of 16 per cent magnetite, the Hawsons project feasibility studies are indicating a positive business case for a large-scale 20 Mt/a of magnetite project for the following reasons:• The mineralisation is on a huge scale, with a major potential for increases beyond the already very large established resource of 1.4 Bt.• The mineralisation is particularly soft for crushing and grinding, with a Bond work index of 6.3 and an overall comminution power requirement of 6.7 kWh/t of ore. This equates to 39 kWh/t of concentrate which is significantly less than for similar projects.• The mineralisation fractures easily, preferentially along grain boundaries.• Location is close to mining infrastructure and a skilled workforce at Broken Hill, 60 km to the northeast.• It is close to road and rail infrastructure for access to the resource.• A high-grade, clean magnetic concentrate can be produced, with the only contaminant being silica.The deposit is a sedimentary siltstone which is considerably different to other known magnetite deposits. This caused significant differences in Davis Tube Recovery (DTR) results between laboratories so that the softness of the ore has required a close focus on, and changes to the laboratory procedures. A DTR procedure has been developed to provide consistent results across the deposit.Crushing and grinding test work has established a clear advantage in the use of the high-pressure grinding rolls (HPGR) crushing and grinding circuit for this particular ore. The power required for comminution using the HPGR crushing circuit is about half the power required for the Autogenous milling circuit.Therefore, despite the low magnetite grades, the Braemar Iron Formation in New South Wales and South Australia has the potential be a new magnetite iron ore province.

Jul 11, 2011

By Streichfuss M, KeBler H-W, Burgwinkel P

This paper describes the design of an expert system used as a part of a diagnostic system for diesel hydraulic drives. A PC-based diagnostic system ruDi (KeBler and Burgwinkel, 1993) was developed to minimise the time for diagnosis and repair work of vehicles with diesel hydraulic drives used in the mining industry. One part of ruDi is an expert system that helps to locate errors in any of a vehicle's subsystems, and supports technicians in removing the cause of a malfunction. Apart from the standard knowledge of diesel engines and hydraulic transmissions, the expert system supports the interpretation of the data obtained during sophisticated engine analysis tests such as high-resolution speed analysis or high-pressure analysis of the diesel injection system. The expert system is designed to diagnose various vehicles of the same type. Data for each vehicle is stored separately allowing checks to be carried out individually for each machine. An additional feature of this system is a database interface to a Maintenance Planning and Control System (MPCS) that allows an automatic generation of work orders for the defects found during the expert system sessions.

Jan 1, 1995

The Mount Sisa orebody on Misima Island, P.N.G., consists of goldsilver mineralisation associated with massive carbonate and amorphous iron-manganese oxides in fractures and breccia matrix. The orebody forms the northern extension of the Umuna deposit, which lies within a three kilometre strike length of a northwest trending, 300 metres wide, high angle fault zone. The structure is deeply oxidised, with the magniferous oxide material resulting from oxidation of carbonate. The wallrocks are metamorphosed basement psammopelites and basic volcanic rocks, extensively intruded by microgranodiorite. These are dominantly epidotised and sericitised. The precious metals are associated with anomalous Cu, Zn, Pb, Mn, As, Ba, Ga, Sb, and Mo. Many of the features of the Mount Sisa mineralisation are characteristic of volcanic-hosted epithermal deposits of western North America.Lithologic and textural gradation is observed between the carbonate hydrothermal breccia-fill at Mount Sisa, and the quartz dominated brecciafill and dilational fracture-fill mineralisation which forms most of the Umuna deposit to the south. This gradational relationship is analogous to that in the Amethyst-OH vein system at Creede, Colorado, where it is shown to be indicative of deposition from laterally migrating fluids.

Jan 1, 1988

By A K. Ghosh, J Chung, E Topal, M Asad

"Many open pit (OP) mines with considerable vertical extent are approaching the end of their life-of-mine; some of them are seeking the opportunity to make the transition from OP to underground (UG) mining. The decision on the best location for transition from OP to UG mining should be addressed at the strategic mine planning stage. Conservatively, the transition to UG mining is considered near or after the exhaustion of the reserve within the ultimate pit.However, if UG is evident and exclusively viable from the inception, defining the best location for the transition through a conservative approach may not be an optimal option to explore. This clearly establishes the need for a mathematical model that aims to maximise the project value and considers OP and UG mining with crown pillar (CP) requirement simultaneously. Underground mine layout varies from one UG mining method to the other, and consequently the variation in the location of transition is eminent. Thus, focus on the selection of UG mining method must be a part of this analysisThis paper presents an implementation of an integer programming (IP) based mathematical model that evaluates the changes in mining layout and the project value under possible variation in the transition point from OP to UG mining for stoping and block caving methods. An IP problem is a mathematical optimisation or feasibility method in which some or all of the variables are restricted to be integers. The outcome of the implementation reflects that mining strategies with OP transition to stoping and block caving methods generated higher values than OP-only mining strategy. The case study not only demonstrates the difference in mining layout for both stoping method and block caving method, but also reflects that a joint consideration of OP mining, UG mining and CP placement helps to achieve maximum project value and resource utilisation.Citation:Darbritz, J, 2016. Remediation of Wall Failure at Kalgoorlie Consolidated Gold Mines' Golden Pike Cut-back 2016, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 96–103 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By Grieveson P, Terry B. S

Carbothermic reduction of sulphide minerals for achieving a selective separation of metallic species from complex minerals has been discussed by considering the prevailing oxygen potential during the course of reaction. Construction of univariant plots for the reduction of sulphides with carbon monoxide gas or carbon and in the presence of either lime or anhydrous calcium sulphate is the key feature of this work. The theoretical calculations for univariants in the Cu-Fe-S-O system indicated a preferential separation of metallic copper and iron by imposing a chemical potential. This is evident from a logarithmic plot of sulphur dioxide partial pressure against reciprocal temperature. The results are compared with empirical data for the reduction equilibrium. The reduction behaviour of the constituent sulphides are also discussed together with the experimental results and theoretically predicted phase stability diagrams.

Jan 1, 1992

By Nava-Vasquez E, Torres-Torres J, Mendez-Nonell J

The ZA-27 zinc base alloy was poured into cylindrical moulds and solidified under different conditions ie normal freezing and unidirectional freezing. In addition a cylindrical ingot with rheocast material was obtained by stopping the stirring action and, at a specific solid fraction, gravity casting it into a graphite mould. It was observed that the material obtained under normal freezing conditions is likely to present both segregation and inverted pipe. In contrast, the unidirectional solidified and the rheocast cylinders showed the absence of inverted pipe. The segregation pattern was quite irregular in the rheocast ingot while such segregation was more uniform in the unidirectional solidified cylinder. By virtue of these observations, the inverted pipe formation may be ascribed to the interdendritic flow, while the irregular segregation pattern in the rheocast ingot may be attributed to an irregular distribution of the liquid and solid fraction along such a cylinder.

Jan 1, 1993

By Wightman D, Hoyle M. W H, Peters W. S

The Radio Hill nickel-copper deposit is located 30 km south of Karratha. It is a new discovery in an area where similar mineralization had been previously discovered at Mt. Scholl and Ruth Well. Radio Hill is the first massive Ni-Cu sulphide deposit of economic significance to have been located in the Western Pilbara.Preliminary studies indicate that the sulphide mineralization occurs within gabbros, pyroxenites and peridotites of a basic igneous cumulate layered sequence. Primary sulphides have been subsequently remobilized and concentrated as stringer and massive mineralization. This is tentatively attributed to the intrusion of a further gabbroic body.The deposit appears to be of the gabbroic association type with a Ni:Cu ratio varying from 1:4 in the outer parts of the mineralized envelope to 1:0.9 towards the central zones. In drill core observations, chalcopyrite surrounding pyrrhotite was noted in many instances. Drilling has so far delineated a body developed over a strike length of 600 m and a horizontal width of up to 25 m. The mineralization plunges 20° to the southwest with a southerly dip varying from 75° in the west to about 20° - 30° in the east.The deposit is a leaf-shaped ore zone, plunging southwest from a vertical depth of 17 m in the north to 300 m in the south. The massive sulphides occur as lensoid masses within this zone. A geological resource of up to 2.5 million tonnes at 1.5 per cent Ni and l.4 per cent Cu is indicated.The predominant sulphides are pyrrhotite, chalcopyrite and pentlandite, with significant cobalt, platinum group metals and gold. Tellurides of Pd, Bi and Pb were detected by scanning electron microprobe within the pyrrhotite and other trace metals include Zn and native tin. Massive magnetite is sometimes associated with the massive pyrrhotite intersections.A test on one composite massive sulphide sample showed that pyrrhotite is present mainly as the non-magnetic hexagonal variety and only 10 per cent is present as magnetic monoclinic pyrrhotite.The deposit has no surface expression and its identification was based mainly Oil drilling targets generated by geophysical methods. No secondary minerals have been observed in association with the primary sulphides, even though the deposit is only 17 m below surface in the northern part.

Jan 1, 1987

By Edwards R

Greater efficiency of capture of minus 6 mm to fine micron size particles of free gold is achieved with the Knelson Concentrator. The development, principles of operation and recent innovations relating to this enhanced gravity concentrating device are described by the inventor, followed by a description of application and consequent economic benefits in low grade alluvial gold deposits by a large scale user of Knelson Concentrators in the Northern Territory of Australia.

Jan 1, 1990

By T McConachy

New opportunities for miners are beginning to appear through new discoveries, improved knowledge and access to vast unexplored areas of the deep sea and continental shelf. Recent discoveries of undersea hydrothermal deposits show evidence of high-grade mineralisation, although in many instances the extent of the resource is still unknown. The promise and the difficulties of undersea mining have been evident since attempts were first made to mine manganese nodules in the 1960s. The physical nature of the undersea resource is a key influence on its mining potential; and environmental issues will also become increasingly important. This paper explores these issues and concludes with a description of the immediate to medium term applied research required to develop this industry and the spin off that such research can provide.

Jan 1, 2000

By J Manuel, L Lu

Increasing bed depth is one of the main options sinter plants consider to increase production, since it is an incremental improvement and less expensive compared with a new plant. To maximise the benefits of increased bed depth, correct blend design and plant operation is critical. This paper discusses test work conducted to show the effects of ore type and bed depth on sintering performance and the adjustments required in both fuel rate and lime addition depending on ore type. The differences in sinter plug macro and microstructure were also examined to show the effect of bed depth on ore assimilation and matrix formation. Finally, the benefits of blending ores to achieve the best sintering performance as bed depth increases is discussed.

Jan 1, 2007

By Lama R. D

The Australian underground coal mining industry is undergoing major changes. This paper analyses the technologies presently being researched in mines, and discusses their utilisation as major contributors in the underground mining of coal in Australia over the next 20 years. It describes the problems that underground mining of the year 2000 will face and the possible solutions to those problems based upon results of present day research. Methods, equipment and organisational requirements are outlined. Developments in micro-electronics, computerisation and monitoring will require a new look into human resource development, education and training, and organisation to meet the challenges of the 21st century. The mining system's philosophies of the future are Outlined.

Jan 1, 1986

Mount Isa Mines' Hilton Mine was brought into large-scale production in 1990/91 at a time of sharply falling metal prices. To ensure the operation's survival and eventual prosperity there was an urgent need to reduce operating costs and increase revenue. A target of a 40 per cent increase in productivity over five years was set. Strategies to obtain the required improvements were developed on the basis of greater involvement and increased contribution from the workforce, major changes to the mining methods and the development and application of new technology. This paper describes the organisational, operational and technological changes that have been implemented at Hilton and presents the results achieved to-date.

Jan 1, 1993

By Z Fu, E Topal, O Erten

"Mine waste rock management involving waste rock movement and placement, is a critical aspect in the planning of open pit mining operations, as the waste rock haulage cost can be the largest portion of the mine operating cost. The concept of sustainable development in the mining industry also encourages environmentally friendly waste dumps that have zero hazards to people and the surrounding environment. Therefore, a detailed waste management schedule must satisfy economic and environmental considerations. However, the available tools in the market cannot provide optimal waste dumping schedules to meet all these constraints. This paper introduces a user-friendly and automatic tool to optimise the waste dumping schedule, which minimises the haulage cost, and covers the encapsulation of reactive materials to minimise acid mine drainage problems. This tool has been developed by using a new mixed integer programming (MIP) mathematical model that considers both single-lift and multilift dumping scenarios. The application of the proposed tool on a data set collected from a gold mine shows that the multilift dumping scenario has provided a more flexible and economical waste dumping schedule than the single-lift scenario, and both scenarios satisfy environmental requirements.Citation:Fu, Z, Topal, E and Erten, O, 2016. A Modified Software Tool for Mine Waste Rock Dump Planning, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 229–242 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By M Behrens, A McPhee, B D. Hegan

This paper describes the design and construction of twin 400 m long road tunnels as part of the Northern Motorway Extension Project in Auckland, New Zealand. Construction of the tunnel civil works is now completed and installation of mechanical and electrical systems is well underway. The tunnels are expected to be open for traffic at the end of 2008. The paper will address the design aspects of the project including: tunnel alignment and cross-section, geotechnical conditions and rock support, waterproofing and concrete lining and fire and life safety. The paper will cover the bored tunnel section, the cut-and-cover tunnel section, cross passages and portal structures. The design brief included a requirement for the tunnels to be a gateway to Auckland and this required particular attention to be given to the visual appearance of the finished tunnel structure. The final arrangement of the portal structures and a requirement for recesses in the concrete lining for emergency cabinets, deluge pipework and cable runs, reflects these requirements. The tunnels were excavated by a roadheader and road planer using a heading and bench. Initial support was provided by a combination of lattice girders, cement grouted rock bolts and steel fibre reinforced shotcrete. The permanent lining consisted of installation of a drainage geotextile and waterproof membrane, followed by cast in situ unreinforced concrete. Each portal consists of a cut-and-cover section. This paper describes the tunnel construction methods, including the particular requirements for safety, the environment and community relations. The tunnel is fitted with a compartmentalised deluge system for fire fighting purposes. The tunnel control centre is incorporated into the control centre for Auckland Harbour Bridge, some 30 km from the tunnel location.

Jan 1, 2008

To follow the development of the central crushing plant it is necessary briefly to outline the history of the Lake View and Star Limited. This Company, when first constituted, took over the properties of the Lake View Consols, Hannan's Star, and Chaffers Gold Mines.The Company then treated the ore won from these leases at two dry crushing, all-roasting plants, situated adjacent to each other on the site of the present Chaffers Treatment Plant that handles all the ore won by the Lake View and Star Ltd.SUbsequent to the initial union of the three companies mentioned, the Ivanhoe Gold Corporation and the Golden Horse Shoe Ltd. were absorbed. Still later, and after the original crushing plant was erected, the Associated Gold Mines of Australia were purchased.A very extensive development policy was adopted by the Company's management in the late 1920's, and as the underground programme progressed, it became eVident that a large treatment plant would be required. Wet milling of the ore, followed by flotation, was considered desirable, and the necessity of a central crushing plant capable of producing a feed that could be handled by the wet ball mills attached to it was obvious.At this time, each of the properties absorbed had its own crushing station, situated adjacent to the respective...

Jan 1, 1948

The Porgera gold deposit in the Papua New Guinea highlands contains about 387 tonnes of gold. The results of its exploration show the benefits of persistence and commitment to this difficult deposit. The mineralization consists of a complex intermix of auriferous and argentiferous sulphides, gold tellurides and free gold as disseminations, veins, stockworks and breccia matrix. Its deposition was structurally contolled within a system of mafic diorite intrusions and adjacent sediments. Two styles of alteration accompany the mineralization. Gold grades vary erratically throughout the deposit. Over a period of 22 years nine phases of exploration have been undertaken by six companies or consortia of companies. Surface rock chip sampling, geological mapping followed by scout and systematic grid diamond drilling have been the most successful exploration tools. Exhaustive metallurgical process investigations and economic evaluations of mining options have been invaluable in guiding the exploration towards defining the ore body. Impetus was given to the project during times of flagging enthusiasm by several important discoveries and a breakthrough in the metallurgical processing approach. The discovery of high grade ore deep in Zone VII in 1984 turned this marginal deposit into a potentially very large gold mine.

Jan 1, 1987

Miners and mineral explorers are concerned at the increasingly hostile environment being generated towards their industry and their profession. There is little official or public recognition that the mining industry is essential for the maintenance of the country's standard of living; a large part of this hostile feeling is caused by the assumption that mining destroys large tracts of our attractive countryside. This paper presents a historic review of the impact on the countryside of the major land using groups commencing with the Polynesian migration. European farming practices, subsequent expansion of the urban dweller and the land management practices of the two Government Departments, Lands and Survey and New Zealand Forest Service who between them control half of the total land area, are discussed. Estimates of total land area to date, directly and indirectly affected by mining have been calculated and a broad estimate of 18 000 ha or 1/1500 of total land area is indicated; current annual mineral production requires some 240 ha. These gross areas take no account of subsequent land rehabilitation, its improvement upon the original in some cases and the recreational, historic and aesthetic areas gained. Comparisons are then drawn with some current land practices in New Zealand.

Jan 1, 1977

The Research Centres Program initiated by the Federal Government and supported by the mining industry has had a major impact on geoscience research and education during the past five years. Eight major university based-Geoscience Research Centres are currently supported by the Government, including four Key Centres of Teaching and Research and a further four Cooperative Research Centres (CRCs). The Research Centres Program has led to a concentration of high quality research and teaching in areas of demand and strategic importance creating strong university - industry linkages and a source of well trained and motivated graduates. Over the last decade Australia's reputation as a leader in mineral exploration and ore deposit research has grown substantially, in part because of the development of the Research Centres Program, and to increased collaboration and interaction between research groups and exploration geoscientists across the industry. During a period when ore deposit research activity has been decreasing in other countries (eg USA, Canada, Japan and most European countries), equivalent research activities in Australia have been increasing, within a well co-ordinated national framework. The future challenge for universities and the mining industry will be to maintain the momentum of the successful research centres in order for the centres to become self-funding over a six- to nine-year period.

Jan 1, 1996