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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 Vynne J. F

Drill monitors for rotary blasthole drills have been available to the mining industry since the 1970s. The early monitors were pen strip chart recorders that were developed for the oil drilling industry and adapted to mining. They recorded drilling parameters such as depth, pull-down pressure, torque, RPM, and hailing air pressure. While these recorders could generate a large volume of paper, the amount of useful data was minimal. The data was not summarised and required an engineer to interpret the chart traces. Being a mechanical recorder, the devices were also susceptible to frequent failures. Modem electronics, and the development of the personal computer and its associated software have radically changed the type of instrumentation that is now available for blasthole drills. Perhaps more important is what can be done with the data. The PC allows the logged data to be analysed, summarised, and a variety of reports to be generated. The reports can be customised to meet the specific requirements of the mine and reduce the amount of time that is required to interpret the data. There is also an increased awareness in the mining industry of the importance of production drills. Blasthole drills have typically been the piece of production equipment that received the least amount of attention in a surface mine. Management focussed on the trucks and shovels or draglines. This situation is changing, and therefore the benefits that can be derived from monitoring drill performance are being recognised. Potential economic benefits of installing drill monitors have been documented in previous papers (Peck and Vynne, 1992). Mines are finding that pay-back periods of less than twelve months and rates of return in excess of 30 per cent are not uncommon. These benefits include the following: 1. Reduced overdrilling; 2. Increased rate of penetration; 3. Helping to locate coal seams; 4. Identification of weak and strong zones; 5. Reduce geophysical logging; 6. Optimising blasts; 7. Improved fragmentation and diggability; 8. Decreased coal dilution; 9. Increased bit life; 10. Reduced maintenance costs; 1 I . Improved accuracy of data and reports.

Jan 1, 1995

By Bayly MG, Harris JA

The current operational practice at the Territory Enterprises Pty, Limited uranium oxide plant,, and some aspects of researc$ and development work at Rum Jungle are outlined with pertinent comments on some overseas practices.

Jan 1, 1968

By S Shipard

Filters are used in water treatment and hydrometallurgical process plants for objectives such as generating a dry spadable solid, pumpable high density slurry or high purity filtrate. The priority objective of every polishing filter, sometimes also termed clarifying filters is high purity filtrate and these are found in many diverse industries and even different applications within the same industry.To generate a high purity filtrate, process designers have the choice of many different polishing filter products, but in reality very few polishing filters are based on fundamentally different filtering concepts.This paper reviews the technology merits of well-known and the more recently developed polishing filter products and aims to assist metallurgists and engineers with the selection of an appropriate polishing filtration technology for pregnant liquor filtration and other process applications, plus a guide to best practice.CITATION:Shipard, S, 2013. Polishing filters for mineral processing plants, in Proceedings MetPlant 2013 , pp 118-125 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By Ward S. C, Gardner J. H

In 1990, Alcoa of Australia Limited was elected to the Global 500 Roll of Honour of the United Nations Environment Program for the environmental management and rehabilitation of the bauxite mines in Western Australia. This award placed Alcoa in the international best practice category. The story of constant improvement spans more than 20 years from a 'trial and error' start to a strategically focussed and research driven program today. The main driving force has come from within the company, against a set of strong corporate values and a well publicised Vision based on 'excellence through quality'. Along the way public opinion, action group protests, increased legislative controls together with the professional competence of internal and external environmental resources have all played a part in arriving at the level of current environmental management and mine rehabilitation performance. There were numerous lessons learned here during the evolution and maintenance of best practice. These included: I . To work diligently in obtaining a vision or strategic intent on mine site rehabilitation and environmental management - don't be easily dissuaded.

Jan 1, 1995

Investigations of the Mineragraphic Section; Commonwealth Scientific and Industrial Research Organisation, have included most of the known stannite-bearing ores in Australia, and have revealed several new occurrences of this relatively uncommon mineral. They provide information about its paragenesis, and its possible effect on tin recovery, that may be of general interest.Several of the investigations used in the preparation of this paper, were made in the first instance by pr. F. L. Stillwell or in collaboration with him.CASSITERITE-SULPHIDE ORES IN NORTH-WEST- TASMANIA Stannite is a minor component of most of the cassiterite sulphide ores of north-western Tasmania. These include the orebodies of Mount Bischoff, the Cleveland mine, Moina, the Stanley River district, Renison Bell, and the Heemskirk-Zeehan district, and form a well defined metallogenetic provence which is related to the Devonian granites of this part of Tasmania.In these ores mineralisation began. with deposition of cassiterite, a little wolfram, and quartz, topaz and tourmaline. With falling temperature, deposition of cassiterite ceased and arsenopy-rite, pyrite, and especially pyrrhotite, formed in abundance, tending to give massive sulphide ore. A little chalcopyrite; stannite, sphalerite and native bismuth accompanied the pyrrhotite. Deposition of quartz ceased after the pyrrhotite, was formed, and the later-formed nonsulphide gangue consists chiefly of carbonates and fluorite. With, the advent of the carbonates the pyrrhotite was altered to fine-gained intergrowths of marcasite and pyrite. Excess iron from the pyrrhotite entered the intergrown carbonate, or was precipitated as magnetite. Some solution of the cassiterite occurred at this stage, the tin being redeposited chiefly as stimnite replacement rims around the residual cassitellrite grains. Varying, but small, amounts of sphalerite, galena, tetrahedrite and silver minerals were depoSited at this stage, bringing the mineralisation to a...

Jan 1, 1951

By J Austin, R Bitencourt

Differences between the long-term model (LTM) and mine geology system (MGS) grade control block-outs on a blast block scale can impose difficulties to planning crusher feed grade and tonnes on a monthly to weekly blend basis. Detailed geological input to short-term planning has been integral to improve the performance and reduce risk in six-week to three-month production schedules and local variability in tonnage and grades is often not accurately represented in the LTM. The challenge of producing to combined target specifications from different mine sites in an integrated mine to ship business has been reduced with the creation of blast blockout-based short-term model. These short-term blast block models (STBBM or STM) are robust predictive tools created for upcoming benches of current mining areas by firstly collecting data from the pit in the form of bench and face mapping and projecting the structure and stratigraphy down to the next bench. A wire-frame of the projected contacts based on material destination from production blockouts is created and then checked against the LTM. Blast block data from the bench above including assay results and material logging is extracted and validated according to the projected wire-frames (geozones). Individual blast blocks and a full block model are created for each bench production defined by the STP (bench plans). Data output from the STM is in a compatible format for import into scheduling specific software packages. Additional information is incorporated into the STM to allow querying of drill penetration rates, predicted powder factors, material hardness and feed type to further aid in the production planning process and cost forecasting. To date, reconciliation of the STM has been pleasing and certainly an improvement on the LTM, especially in areas where variability is higher due to geological complexity. Short-term predictions derived from in-pit geological observations allow mine planners to more confidently decide on mining block sizes and schedule tonnages and grades, reducing the risk component attached to developing production schedules based directly upon long-term orebody models and mine plans.

Jan 1, 2005

By N Fullelove

The Renison Bell Tin Mine on the West Coast of Tasmania has recently installed a new underground ore handling system incorporating underground crushing, conveying and hoisting facilities. Contracts for the sinking of the shaft and the development of the mine were let and managed by the operator, Renison Limited. Hardcastle & Richards was responsible for the design, procurement and construction management of the fixed plant and equipment including civil, structural, mechanical, electrical and instrumentation services. The system demonstrates worldÆs best practice in design and incorporates a state-of-the-art integrated control system allowing the entire system to be controlled by a single operator located in the underground crusher chamber. A rapid construction period was achieved, despite the difficult and constrained underground environment, without affecting the ongoing operations of the mine. The mine, which was established in the mid-1960s, had previously operated by trucking ore to the surface via a decline. Truck haulage distances and costs had increased as the mine became deeper over the years. By the 1990s it had become apparent that, in order to remain economically viable, it was necessary to reduce truck haulage distances and allow the mine to go still deeper to access orebodies such as Rendeep beneath the current workings. The Internal Shaft System achieved this by eliminating approximately 5 km of truck haulage. It allows the production rate to be increased to up to 1 Mtpa compared with a limit of 628 kt per annum by direct truck haulage to surface. The access it provides to the Rendeep ore and other deep orebodies greatly increases the amount of ore which can be economically mined.

Jan 1, 1998

By Elford H. S

Australia has many potentially important tin deposits, particularly on the eastern shore of the continent and in Tasmania. A number of these have been worked on a meagre scale, while some of them, because of metallurgical, transport, and other difficulties, have not as yet been developed.Believing that the full development of the tin fields of the Commonwealth of Australia is in part dependent upon the adoption of the most efficient methods of milling and smelting, the Development and Migration Oommission arranged for the first-mentioned author to visit the mining fields of Cornwall, one of the oldest tin-producing districts of the world, and prepare a report for the information of the Commission.This paper, now presented to the Australasian Institute of Mining and Metallurgy with the hope that it will assist the full development of tin mining in Australia, is the joint work of both authors.For over two thousand years tin has been produced from the Cornish mines. Even the ancient Greek historians made mention of tin mining in Cornwall, and it is probable that during the earliest periods the mining was alluvial. As early as 1602 a stamp battery working in Cornwall was described, and in 1671 calcination and buddling was a recognised scheme of treating pyritic ore. In the first half of the 16th century the output of tin from Cornwall was 700 tons per annum, and, from then on, production increased to the maximum in 1914 of 6500 tons. At present (Oct., 1929) the Cambourne-Redruth area produces over 95% of the Cornish tin output. This area includes such mines as the South Crofty, East Pool, Dolcoath, Parkanchy, Polhigey, and Wheal Kitty. The remaining 5% is largely supplied by the Levant and Geevor mines at Pendeen, St. Just area, near Land's End.

Jan 1, 1930

By T Hayward, G Lane, M Phillips

In December 2004 Phu Bia Mining Ltd commissioned Ausenco International Limited to conduct a feasibility study for its Phu Kham copper-gold project located in Laos. The feasibility study for a mining and processing operation treating 12 Mtpa of ore averaging 0.56 per cent copper and 0.25 g/t gold to produce an anticipated annual average 200 000 t of concentrate containing 25 per cent copper was completed in early 2006. The plant design incorporates a single processing line and includes a gyratory crusher, overland conveyor, coarse ore stockpile, SAG and ball mill grinding circuit, flotation circuit including regrind and three stages of cleaning, concentrate dewatering and concentrate load-out facilities. The Phu Kham copper-gold mineralisation comprises two principal styles: stockwork-disseminated and banded-massive sulfide within skarn limits. Primary copper in both mineralisation styles occurs as chalcopyrite and secondary copper sulfide minerals. Skarn includes the copper and gold mineralisation contained in pyrite, silicate, magnetite and haematite skarns, and in quartz-pyrite altered sediments. Both the stockwork-disseminated and banded-massive sulfide ores contain relatively high proportions of pyrite relative to the copper and gold mineralisation. Thus, the flotation metallurgy of the Phu Kham orebody is characterised by the need to reject a high proportion of the pyrite during differential flotation to yield a concentrate grade of approximately 25 per cent copper. The rejection of pyrite is accompanied by the rejection of some copper and gold and can result in modest metallurgical recovery. Consequently, the greater the pyrite content, the lower the expected copper and gold recoveries. The relative pyrite content is expressed on the basis of sulfur:copper ratio. For Phu Kham ores, the sulfur:copper ratios are in the range eight to 14 on a blended annual basis, but can be greater than 20 in the skarn components. Higher grades of copper and gold are also present in the skarn mineralisation. The design concepts for the concentrator were influenced by the need to provide a low capital cost approach for the project due to the relatively low grade of the ore and the modest metallurgical recovery. The concepts used to minimise capital cost whilst retaining operating and maintenance flexibility are discussed, together with the metallurgical challenges imposed by the high pyrite mineralisation.

Jan 1, 2007

Aspiring to be excellent makes you a good leader as it shows a capability for strategic thought, defining and implementing a vision, making a job easier, more efficient and effective. Every great business leader can generate additional revenue or cost savings for their company. Becoming excellent requires the desire and action to follow it through. There are many established methods of excellence: benchmarking, target setting, supply chain and market analysis, employee suggestions and knowledge sharing forums. In BHP Billiton, practices benchmarking is a key tool in generating improvements for functional areas such as processing, mine operations and mine planning. Practices Benchmarking involves organisational and technical questions that allow the site to self-assess their maturity and generate a prioritised improvement path. Not only does it benchmark and identify gaps, but the approach also facilitates networking, education and team building. For new leaders it is important to remember that you are not alone. Chances are your problem has been solved before. Networks û internal, external, formal and informal can get you started and often save you time and effort. Any leader can achieve success in excellence through a proper process of problem formulation, data and analysis. Again, using key players can make the process more effective. It is important to remember that the people side of the solution is the key to success and that monitoring will ensure the solution will work. In the words of BHP BillitionÆs CEO, Chip Goodyear: Excellence is a mind set. ItÆs something that comes when people get rewarded forthinking outside the box and applying their skill and knowledge. It happens, not in$50 million chunks, but in hundred thousand and million and $2 million chunks.When you get 35 000 people thinking that way, then youÆve really got somethinggoing.

Jan 1, 2005

A short overview of the research program of SveBeFo, Swedish Rock Engineering Research, which was founded in 1993 is first given. Then four recent and ongoing projects in rock blasting and explosives engineering are presented in greater detail: 1. Burn Equations for Commercial Explosives. 2. Blast Damage in Contour Blasting. 3. The Role of Gas Pressure in Pit Wall Damage. 4. Fragmentation of Aggregate Rock. The goal of the bum equation project is to be able to control the energy release from explosive charges to the desired part of the expansion curve of the reaction products under various rock conditions. SveBeFo's work has reached the stage where a burn equation for a lab emulsion has been established which can model the influence of charge diameter on the VOD and detonation front curvature in a cylindrical charge quite well. This work now continues with other emulsion recipes. In the blast damage project the goal is to develop techniques and recommendations on how to minimise the blast damage in construction blasting. The project has gained extensive practical knowledge from the blasting of more than 200 holes in a granite quarry under controlled conditions. The cracks in the rock surrounding the contour holes have been cut open and measured. The influence of factors like charge concentration, decoupling ratio, hole and charge size, VOD and time delay in initiation have been investigated. A simultaneous initiation of a group of contour holes with EDD detonators is quite superior to single hole blasts, even when they are timed as closely as 1 ms.

Jan 1, 1995

Broken Hill is situated at an elevation of approximately 1000 ft. above sea-level, on the Barrier Ranges, in the State of New South Wales, Australia. It is approximately 700, 280 and 330 miles from the ports of Sydney, Pirie, and Adelaide, respectively.The summers are usually hot and dusty, with a recorded maximum shade temperature of 114° F. The rainfall averages approximately 9 in. per annum.

Jan 1, 1932

The Crown Minerals Act 1991 has introduced some significant changes to the New Zealand mining industry, not the least of which relate to the ability of miners to obtain access to land to conduct mining activities. This paper briefly reviews the relevant provisions of the Crown Minerals Act dealing with access arrangements, considers some typical features of access arrangements and examines a number of areas where problems may arise.

Jan 1, 1992

By Lawrence L. J

The Australian Broken Hill Consols Mine, situated some 600 yd east of the main Broken Hill line of lode, is noted for its rich ores of silver. In contrast to the vast conformable orebodies of the Broken Hill field, the Consols lode occupies a narrow fissure dipping to the south west at angles increasing from 240 through to vertical and transgressing the strike of the metamorphosed country rock at an oblique angle. This feature, together with the abundance of calcite and siderite and the virtual absence of silicate minerals in the gangue, has led to its classification as an orebody of the Thackeringa type (King, 1953). Recorded production during the period 1890 to 1903 is given as 845,000 oz of silver and 20 tons of lead.The unusually rich silver values of the Consols lode were concentrated at the intersection of the fissure with beds of amphibolite, whereas in the adjacent schists and gneisses the lode became markedly impoverished. From the surface to a depth of some 120 ft extensive surface oxidation had occurred, resulting in the breakdown of siderite and its replacement by limonite and associated manganese oxides.Silver halides, dyscrasite, acanthite and partly oxidised tetrahedrite were the main silver minerals in this zone. With increasing depth the lode material gradually reverted to minerals representative of the hypogene zone.The only previous work specifically on the mineralogy of the Consols lode is that by Smith (1922), one time manager of the mine. His zeal as a mineral collector resulted in much valuable information being available on the distribution of the minerals. More recently, Garretty (1943) noted the...

Jan 1, 1962

INDEX OF CONTENTSIntroductionThe slag samplesGranulated SlagGlass-spinel-magnetite-metallic leadRapidly Chilled SlagSlowly Cooled SlagSpinel - magnetite - zinc melitite (hardystonite) willemite - olivine -lead silicate - metallic lead - lead sulphide - copper sulphide - copper arsenide - nickel arsenide.ConclusionsIllustrationsINTRODUCTIONThis paper presents the results of a mineragraphic examination of representative samples of granulated lead blast furnace slags from the Port Pirie Smelter, and of slowly cooled samples of t:b.e same slags, undertaken at the request of the Broken Hill Associated Smelters Pty. Ltd., as part of the research programme of the Mineragraphic Section of the Commonwealth Scientific and Industrial Research Organization.THE SLAG SAMPLESThe chemical composition of the slags examined is given by the following three analyses of the granulated slags, supplied by the Broken Hill Associated Smelters (Table 1).

Jan 1, 1949

By T QUINLAN

A resource estimate uses data obtained by sampling an orebody. An example is described in which a random drilling pattern did not provide a representative set of assays, and the estimated resource was significantly less than the mine production. It is believed that a better estimate would have been made if the exploration holes had been drilled on a regular grid.

Jan 1, 1992

By M D. Basuki Dwi Priyono

The Toguraci low sulfidation epithermal gold vein deposits are located 2 km WSW from the Gosowong mine and form part of the Gosowong Goldfield. The goldfield lies within a Neogene magmatic arc on Halmahera Island, North Maluku Province, East Indonesia. The terrain is moderate to steep, rainforested, and poorly outcropping. Exploration and mining operations are being carried out within the PT Nusa Halmahera Minerals Contract of Work (exploration tenement) jointly owned by Newcrest Mining Ltd (82.5 per cent, operator) and PT Aneka Tambang Tbk. (17.5 per cent). First pass exploration of the Gosowong area began late 1992 resulting in the discovery of weakly developed porphyry copper mineralisation (named Bora) at Toguraci in 1993. Early in the evaluation of this porphyry an overprinting epithermal Au/Ag mineralisation event was recognised, however exploration focus remained on the Bora porphyry deposit for some time. The discovery of the nearby Gosowong epithermal gold deposit and the exploration of other prospects in the area further diverted attention and funds from Toguraci. It was not until year 2000 that Toguraci was seriously reevaluated as part of a detailed appraisal of the epithermal gold potential within a 5 km radius of the Gosowong gold mine. A fly-camp based drilling campaign using man-portable rigs was undertaken between August 2000 and March 2002. All exploration at Toguraci was then stopped pending government approvals to mine. These were finally issued in May 2003 and immediately drilling restarted and pre-mine approvals (eg the environmental impact study) were sought and granted. The first Toguraci gold bar was poured in February 2004. Exploration at Toguraci and elsewhere in the Gosowong Goldfield continues today.

Jan 1, 2004

By A Tomsett, J Rutter

Ore control systems at Ridgeway have been designed to deliver gold and copper metal production through focussing on the ore characteristics that impact on mine and mill performance and ultimately metal delivery. This is achieved using data collection and management systems which allow data to be collected digitally with æat captureÆ validation routines. This data forms the basis of forecasting systems which aim to accurately assess local in situ and drawn ore characteristics. Physical attributes of ore such as draw characteristics, brow conditions and visual grade estimation are rountinely recorded. Ore tracking and accounting systems monitor gold and copper grade, copper mineralogy, host lithology and ore sizing. These have material impacts on concentrator throughput and metal recovery. Routine reconcilation and check sampling allow calibration of these systems.

Jan 1, 2002

By R C, K L. Rees, J S. J van Deventer

In contrast with previously published models for the carbon-in-pulp (CIP) process, the model proposed in this paper incorporates film transfer, intraparticle diffusion, simultaneous leaching, preg-robbing, the loading of multicomponent species, and the effects of fouling and changing cyanide levels. The rationale behind this comprehensive model is that changes in fouling and competitive adsorption along a CIP cascade affect the profiles of gold loading. As it is impossible to quantify all these non-ideal factors, a method is proposed whereby an imaginary species is postulated so as to combine all the competitive effects. A plant survey at the Telfer mine has shown that the mass loss due to a gravimetric analysis of the fouled carbon could be used directly to quantify this competitive effect. The degradation and consumption of cyanide along the Telfer CIP cascade enhance the loading of copper on to the carbon, which should be taken into account when modelling the gold profiles. It appeared that the effect of cyanide itself on the loading of gold was negligible compared with its effect on the copper. Evidently much more research is required on this topic in order to optimise CIP operations exposed to constantly changing conditions.

Jan 1, 1998