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Christmas Island "C"-grade phosphate consists essentially of the minerals crandallite and millisite. Although containing over 25% P205, this material is not suitable for the manufacture of water-soluble phosphate fertilizers by conventional processes, because of its high iron and aluminium content Cover 25% total R203). In order to produce a water-soluble fertilizer from such material it is necessary to separate the iron and aluminium from the phosphate, which must report in a product acceptable as a fertilizer. Several processes were studied in detail. The first used ion exchange for dissolution and separation and yielded diammonium phosphate; processing costs were high compared with conven- tional processes based on apatite. The latter processes have basically simple flowsheets and cost of processing is low when compared with the costs of the raw materials. The need to separate iron and aluminium from the phosphate introduces additional complexity into the treatment of the C-grade material. The higher processing costs might be justified, however, if alumina could be produced as a byproduct. Two proposed processes have been developed in which: 1. hydrochloric acid is used for dissolution, and solvent extrac- tion for the separation of ferric chloride from phosphoric acid. Aluminium chloride is precipitated and hydrolysed to recover alumina and hydrochloric acid. 2. sulphuric acid is used for dissolution and aluminium is crystallized as ammonium alum. The phosphate is produced as an ammonium phosphate-sulphate fertilizer. High purity alumina can be obtained by treatment of the recrystallized alum. The technology of these processes is described, and their broad economics discussed briefly.\

Jan 1, 1971

WHEN reading reports on reefs and lodes, one often comes across the statements "short shoot," "narrow shoot," "wide shoot," & c.From a number of reports in the writer's possession, some by members of the Geological survey, it is plain that the words "short," "narrow," "wide," "long;" &c., are used somewhat carelessly.In one official report on a certain field, for instance, the reefs are described as having "short, rich shoots"; another report on the same field states that "the reefs were characterized by narrow shoots, rich at the surface." Again, Charters Towers is described as having "wide shoots"; another writer says they are "long shoots. "The writer has read again of "short shoots which went down like pipes," and of "narrow shoots of limited extent." No doubt one can make out what is really meant, but the language is mixed. It is apparent that "narrow" is meaning the same as "short," and that the shoot has not much length in a horizontal direction. Nothing is said about the thickness or width of 'said shoot, or its depth. The "wide" shoot is evidently a "long" one; its thickness 01' width and depth is not specified. When we consider these terms, it is seen that only a few words are needed, and that these few should (as they do) have a definite meaning. In the course of his mining experience, the writer has seen shoots of almost all sizes, and some have been very long (in horizontal measurement), and have been followed down for great depths, these shoots being the best type-Charters Towers, Walhalla, &c., are examples.

Jan 1, 1909

By Sennitt C. M, Hartley J. S

The Twin Hills Gold Deposit is an example of a preserved, high level, epithermal system, with mineralisation introduced contemporaneous with deposition. The deposit is hosted within sediments of the Late Devonian to Early Carboniferous Saint Anns Formation, of Cycle 1 Drummond Basin stratigraphy, situated in central Queensland. Prior to epithermal activity in the Twin Hills region, a lacustrine fan delta depositional environment existed, together with minor tuffaceous activity. An and palaeo climate, with occasional periods of torrential rainfall, together with a basin with faulted margins, allowed alluvial fan prograda- tion. Cyclical repetitions of the fan indicate repeated faulting and seismic activity took place during deposition. Significant gold mineralisation was first intersected at Twin Hills by Metana Minerals NL in 1988, after drill testing a "blind" target outlined by geological mapping and bedrock geochemistry.

Jan 1, 1991

Some important mineral fields are referred to in discussing the formation of placer deposits in Australia. Testing methods include boring hand, with percussion rigs; with auger and pit digging drills; and l by vibro drilling. Sampling errors are minimized by the use of correct techniques and equipment for boring, sampling, and sample dressing, A hypothetical set of data is used to demonstrate the final process of evaluation, and some relevant taxation provisions are discussed.

Jan 1, 1964

The Kidston breccia pipe is situated approximately 280 km west northwest of Townsville, north Queensland. It is currently Australia's largest gold producer with production varying between 8,000 and 16,000 tonnes of ore per day. Current reserves are estimated at 36.2 million tonnes averaging 1.74 C/t Au and 2.21 g/t Ag. Alluvial gold in the gullies surrounding the deposit was first discovered in the 1880's and between 1907 and 1948 small scale open cut and underground mining was undertaken. Advances in extractive metallurgy and an increase in the gold price were major factors influencing the recent exploration and development of large scale mining of the deposit by Placer Pacific and Kidston Gold Mines. The breccia pipe is trapezoid in shape with surface dimensions of 1100 m by 900 m. Clasts show only limited evidence of mixing during brecciation, with the pre-breccia stratigraphy still discernible on the basis of clast types. This lack of mixing together with the intimate association with intrusive activity, suggests that the brecia formed by collapse, probably associated with the escape of a large volume of irothermal fluid from a crystallising hatholith. Mineralisation and alteration are also sratially and temporally associated with rhyolite emplacement and brecciation. Pre-breccia mineralisation consists of laminated stockwork quartz veins associated with muscovite, quartz and orthoclase-epidote alteration. Stockwork veins contain either anomalous molybdenite or gold. Uneconomic early stage post-breccia mineralisation and alteration consists of cavity infill quartz-epidote and calcite associated with potassic and propylitic alteration respectively. Economic late stage post-breccia cavity infill and sheeted veining consists of quartz-carbonate-sulphide infill associated with phyllic alteration. The grade of gold mineralisation generally decreases downwards in the system with an increase in the amount of pyrrhotite relative to pyrite. Pre-breccia stockwork quartz veins mineralisation is genetically related to the

Jan 1, 1987

By Georgi H, Farquhar J. W, Lorrigan A. N

The potential for major new lenses of Volcanic Hosted Massive Sulphide (VHMS) beneath the existing Rosebery Deposit is extremely high. Recent deep drill hole intersections of massive sulphides, including 22 in true thickness at 24 per cent Zn, may significantly extend the life of the Rosebery Mine. The Rosebery Ore Deposit is located within Australia's most prospective VHMS mining district, the Mount Read Volcanic (MRV) arc of western Tasmania (Figure 1). The MRVs are a 10 - 15 krn wide arcuate belt of lavas, related intrusives and volcaniclastics. Rosebery is a major Cambrian volcanic hosted Zn-Pb-Cu-Ag-Au rich deposit which has been over-printed by Devonian deformation and granitoid alteration resulting in local rcmobilisation of the ore. The Rosebery Mine Sequence is composed of an east dipping and east facing, predominately felsic sequence of rhyo-dacitic volcaniclastics, epiclastics, sediments and shale lenses more than 500 in thick. This sequence is bounded by two, low angle (35 - 40¦), east dipping thrust faults, the Rosebery Fault to the west and the Mount Black Fault to the cast. The Rosebery Mine lithologies are summarised in the following table: Hangingwall (HW) Polymictic, quartz, feldspar-phyric epiclastics. Black Slates Graphitic, pyritic mudstones. Host Rocks Turbiditic mudstones and sandstones. Footwall (FW) Feldspar-phyric, pumiceous, mass-flow breccias. Cambrian, quartz-feldspar, porphyritic sills intrude this sequence at all levels. Thin, Jurassic, dolerite dykes also occur throughout the mine. Widespread quartz, sericite and chlorite alteration occurs in the FW. This alteration is manifested as quartz-augen schists beneath the orebody. The Host Rocks are pervasively altered with silica, sericite, chlorite and pyrite. Intense carbonate alteration occurs within the orebody, whereas chlorite and pyrite alteration is commonly concentrated directly beneath it. Cambrian volcanogenic alteration is over-printed by three major Devonian, granite-derived, assemblages. These are massive to quartz veined tourmaline, pyrrhotite-pyrite and magnetite-chalcopyrite. Though the Devonian granite has not been intersected in deep drill holes or in mine workings, there is good evidence that it exists within a kilometre of the deposit. The Rosebery orebody is structurally complex when compared to many other VHMS deposits. Evidence for Cambrian growth faulting has been found at the North End of the mine (B lens) where displacement of ore lenses occurs without corresponding displacement of the overlying Black Slates. A well defined cleavage exists throughout the mine, dipping at 28 to 50¦E. East dipping shear zones are also obvious in all parts of the mine workings and reverse movement is evident on many of these.

Jan 1, 1993

The Ocean Drilling Program is the largest international geoscience project in the world, and the state-of-the-art drill ship, the JOIDES Resolution, is permanently at sea. Each year there are six scientific cruises (Legs) which each last approximately two months. These legs are designed by geoscientists from the 19 countries that subscribe to ODP. Australia and Canada share ODP membership under the banner of the AUSCAN Consortium. The Australian Secretariat of the ODP is housed at the Department of Earth Sciences at James Cook University, along with the AUSCAN Consortium office. The Canadian Secretariat is presently based at the University of Toronto. Both secretariats have major research interests in the ore deposits, both ancient and modem, and so there is currently a major drive by the AUSCAN ODP Consortium to make available data and technological information to the minerals industry. This type of information includes data from drilling hydrothermal sites such as the hydrothermally active TAG black smoker complex on the Mid-Atlantic Ridge, drilled during Leg 158, and the Middle Valley sulphide deposit, on the northern Juan de Fuca Ridge, which was drilled during Leg 139.

Jan 1, 1996

By McOnie A. W, Rutherford PG

A volcanic sequence is described from the Golden Cross Mine, Waihi, New Zealand. The sequence includes seven lithostratigraphic units comprising flow and pyroclastic units of Coromandel Group andesite and dacite and overlying Whitianga Group dacite and rhyolite which is intruded by the Golden Cross dacite porphyry and rhyolite dykes. The sequence is mineralized and is unconformably overlain bv_ two post-mineral units, the lacustnne Waitekauri beds and Omahine Subgroup andesite. Detailed structural analysis of mine data has identified four deformational events (D 1-D4) and related these to the gold-silver mineralizing events. Faulting was coeval with the mineralization and directly controlled the development, localization, style and geometry of the ore shoots. Mineralization developed in competent lithologies where dilation occurred during faulting. The Empire Fault is the master shear which controlled fluid flow. Mineralized veining developed in response to tectonic pulses occurring at slightly different stages as represented by the underground Empire vein complex and the open pit vein array. The mineralizing events culminated with the deposition of barren calcite veins. Post-mineral movement along the Western Boundary fault appears to have offset the ore body.

Jan 1, 1995

The use of black and white and colour infrared film in remote sensing of natural resources, is reviewed. In heavily-forested areas such as New Zealand, the main value of the method is in surveying the vegetation cover to detect the existence of plant communities characteristic of specific geological formations, By contrast, in and areas of Australia where the vegetation cover is sparse and where rocks and soils are well exposed, the method can be used in detecting different rock types or other geological differences.

Jan 1, 1971

By Liu Q, Siefken T. C, Misra V. N

Investigation of the differential flotation characteristics between arsenopyrite and pyrite in a ore concentrate have been carried out on a laboratory Leeds flotation cell. Experimental results indicate that some limited separation between arsenopyrite and pyrite is possible by differential flotation under the conditions of high pH and low pulp redox potential. The best performance in this testwork was achieved by using an oxidizing agent at pH 10.7. Of the oxidizing agents tested, NaOCI gave better oxidizing effect than KMnO4. It has also been observed that the pulp redox potential depends on the pulp pH value. At high pH values a hydroxide layer is formed on the arsenopyrite surface, which has the effect of a depressant on the arsenopyrite.

Jan 1, 1992

Economic and environmental pressures are shifting the world balance of titanium dioxide production away from sulphate based. manufacture towards the more cost effective and cleaner chloride route. In the chloride process for titanium dioxide pigment manufacture, TiOz and other metal oxides in the feed ore are reacted at high temperature with chlorine in the presence of carbon. These gases are cooled after they leave the reaction zone, upon which solid contaminants precipitate and are substantially removed. The liquid titanium tetrachloride is purified by distillation before again being vaporised and interacting with hot oxygen to form pigmentary titanium dioxide and regenerate chlorine for recycle. The base pigment is wet milled, surface treated (by coating with hydrous oxides of silica, alumina and others) and redispersed before packaging. Optical properties of TiO2 pigments are reviewed and the role of refractive index and particle size explained in brief. Pigment related factors affecting the opacity, colour, undertone, gloss and durability of coatings are examined with respect to manufacturing requirements. The superior performance of chloride based pigments is briefly reviewed.

Jan 1, 1991

The New South Wales coal industry is a highly mechanised well organised industry which has developed from an annual production of slightly less than 13 million tons in 1950 to over 33 million tons in 1969. Although continuous miners were not introduced into the mines until 1950, by June 1969 the percentage of coal won by these units was 87.3. The paper describes mining conditions in the various coalfields of the State, their complexities and problems and how these have been dealt with. The introduction of fully mechanised longwall faces has presented a challenge which has been accepted and descriptions of systems in use are discussed. Major expansion of the industry is anticipated to meet the requirements of the growing Australian steel industry, for local power generation and to meet the increasing demands of overseas markets.

Jan 1, 1980

By Clark G

The latest addition to the grinding circuit at Bougainville Copper Limited is another 5.5m by 7.3m primary mill (No.13). The mill can operate in a primary or secondary mode. Its distinguishing feature is its capability for speed variation, by means of a cycloconverter-fed synchronous ring motor. The engineering and metallurgical reasons for selecting such a drive system are described together with aspects of the installation and commissioning. Results of investigations into the relationship between mill speed and grinding efficiency are presented. It is concluded that mill speed variation within the range 70 to 80% of critical speed has very little effect on grinding performance. Beyond this range, grinding performance deteriorates. The same conclusions were reached when mill speed was varied at reduced ball charge levels.

Jan 1, 1986

The South Comet mine is an underground silver-lead-zinc mine located on the West Coast of Tasmania with an annual production in the order of 35 000 tonne per year. All ore mined is shipped to the Rosebery mill by road, a distance of 17 km.

Jan 1, 1993

Australia is a highly significant hub in the global minerals business. This paper will present the results of global and national studies looking at the potential 20 to 30 year future evolution of the mining and metals industry.   Globally, the World Economic Forum launched a Mining and Metals Scenarios project in January 2009 to explore the question: 'How will the environment for the global mining and metals industry look in 2030?'. As part of a structured strategic foresight process, eight workshops were held across the world over the course of a year which brought together over 200 leaders from the private sector, government, academia and non-governmental organisations. The workshops were supplemented by personal interviews and guided by an international advisory board.   Critical uncertainties for the future of the industry were identified and compare extremely well with the outcomes of a national survey of AusIMM members identifying the key issues and drivers shaping the future of their operations. Global context was one of the most significant issues identified by The AusIMM membership, which is expanded in the World Economic Forum study in terms of: geopolitics; global governance; action on climate change; and economic outlook. More specifically, this global study developed three divergent yet plausible scenarios describing potential environments for the global metals and mining industry in 2030. These scenarios are compared with ground-breaking global foresight work coordinated by the Stockholm Environment Institute in the 1990s. The scenarios will help decision makers rehearse alternative futures, anticipate potential hazards and identify business opportunities - new solutions, new markets and new connections. The presentation will present these scenarios as a way of challenging thinking, testing established wisdom, and stimulating imagination about the business case for the mine of the future. As Marcel Proust put it, 'The real voyage of discovery consists not in seeking new landscapes but in having new eyes'. This is an ABSTRACT ONLY no paper was prepared for this presentation.

Jun 1, 2010

The education system today is turning out potential Mine Managers and Superintendents for the coal industry who are lacking in adequate management knowledge. They are required by the Mining Act to be highly skilled operators who are operations and production oriented. This puts them in much the same category as airline pilots and ships' captains. The real need is for them to be management and profit orientated. Changes over the years in Managers' and Superintendents' roles are highlighted by identifying those professions and vocations with whom they must now work. Comparing classifications in the 1916 award and the current award, and making a comparison between management and mining degree courses, leads to the conclusion that separate degree courses are necessary for future Mine Managers and Mining Engineers. Mine management must become a profession in its own right if optimum profits are to be made from mining in the future.

Jan 1, 1980

The Osborne copper-gold deposit (within the Trough Tank project area) is located in the Cloncurry Shire about 195 kilometres south-east of Mount Isa. It is hosted by Proterozoic metasediments of the Eastern succession of the Mount Isa Inlier. The deposit is overlain by 25-40 metres of Mesozoic cover, so it represents a true "blind target". Placer Exploration has 100% outright ownership of the property, having purchased the remaining 10% interest in the property from Shell in early 1993.Intensive exploration, both surface and via drilling at Osborne, has taken place since 1985, when CSR Limited Mineral Exploration and Development Group (acquired by Placer in 1988) entered into a joint venture with Billiton Minerals. Exploration effort from 1985 to June 1988 outlined a 20 kilometre strike length of magnetic horizons, in what was termed the North-East, Central and Southern anomalies, which were drilled with weak indications of copper-gold mineralization in the North-East anomaly. During the later half of 1989, four core holes were drilled into the shallower northern partofthe North-East anomalywhere previous drilling had outlined economic intersections of mineralization. These holes encountered high-grade copper-gold mineralization confirming the potential for an economic deposit to be hosted within the ironstone sequence. Further drilling involving over 400 holes (100 kilometres of drilling) has brought the deposit up to its present resource status.The current resource inventory is 36 million tonnes grading 2.0% copper and 1.0 grams pertonne gold and includes a high-grade zone of 13 million tonnes grading 3.6% copper and 1.5 grams per tonne gold. The discovery of this potential economic mineralization resulted from a persistent exploration effort based on indications that a large mineralizing system existed within a sequence of ironstones.

Jan 1, 1993

A significant resource of uranium has been discovered within a buried palaeochannel located in the south western corner of the Officer Basin of Western Australia by PNC Exploration (Australia) Pty. Ltd. The mineral- isation is redox controlled and is hosted by Eocene organic rich paludal sediments. Prob- able insitu reserves are 13,000 t of contained uranium with an average ore grade of 0.12% at a cutoff grade of 0.03% U. The Mulga Rock palaeochannel has been traced for at least 100 km beneath the Quaternary surficial cover. The main channel is horseshoe shaped with the channel arms vary- ing from 5 to 15 km in width. The western arm connects to the Lake Raeside-Ponton Creek drainage system, whilst the eastern arm'is open to the south. The headwaters of the palaeo- channel are thought to have been the Lake Minigwal drainage system, prior to its capture by the Lake Rason system. Differential.erosion of the basement rocks during the Late Cretac- eous to Early Tertiary strongly influenced channel shape and resulted in the main channel being confined to a Permian,mudstone filled valley. Upwards of 100 m of fluviatile sediments accumulated within the palaeovalley during a period of subsidence in the Early Tertiary. Three broad stratigraphic units have been re- cognised within the channel: 1. An upper unit of fluviatile sands with interbedded lacustrine sediments, which have subsequently been wholly oxidised and variably silicified and ferruginised. 2. A middle unit of lacustrine to paludal sediments, which host the main mineral- isation. 3. A basal unit of fluviatile gravels and sand. The presence of excellently preserved Nothofagidites in organic rich paludal sediments from the middle unit, suggest that unit was laid down in a non-marine, fluviatile, humid environ- ment during the Middle Eocene.

Jan 1, 1988

The Escondida Porphyry Copper Deposit, located in Chile's II Region 160 Km to the southeast of the city of Antofagasta, is currently owned by Minera Escondida Limitada, a company comprising The Broken Hill Proprietary (57.5%), Rio Tinto Zinc (30%) a group of Japanese companies represented by Mitsubishi Corporation (10%), and the International Financing Corporation of the World Bank (2.5%) (Fig.l)By 1983, most of the reconnaissance drilling was completed and prefeasibility studies were regularly updated as new drilling results were reported and project concepts re-evaluated (Fig.2). In October 1982 the project was transferred from Exploration Management to Operations. By the end of 1984 project pre-development activities, including inpit development drilling, geological exploration, water resource definition, an underground bulk sampling program and the initial project feasibility report, were completed.

Jan 1, 1990

By Mowat B. A

I lamata is within the Morobe Goldfield (7¦ 25' S, 146¦ 39' E) on the Wau (SB 55-14),1:250,000 scale map sheet (Fig 1). The deposit is 13 km SW of Wau, within the headwaters of the Upper Watut River, at an average elevation of 2000 m. The steep mountainous terrain is covered by dense tropical rainforest and access is by helicopter or by foot track. The deposit has been described previously by Wells and Young (1991) and 1)enwer. Leach and Mowat (1995). Data collected to late 1996 have been used to estimate an Inferred Resource of 9.2 Mt at 3.1 g/t gold using a cutoff of 0.5 g/t. This contains a high grade portion for which an Inferred Resource of 1.2 Mt at 9.7 grt gold has been estimated using a 5.0 g/t cutoff.

Jan 1, 1997