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By R R. Anand

Recent research by CRC LEME from an Australian mineral exploration perspective, has focussed on regolith architecture and mechanisms of geochemical anomaly formation, within transported regolith. Methods have been developed for the rapid production of regolith-landform maps which is the starting point for understanding regolith architecture in the third dimension. Methods for development of 3D regolith models are less well advanced, and require integration of all available geological and geophysical datasets, but still with a heavy reliance on drill-hole information. The base of the transported regolith û the unconformity û remains the most important regolith boundary for geochemical sampling in transported regolith terrains. A new generation portable spectral logger, employing a broader spectrum can interpret important features from drill chips within the regolith. This allows internal architecture, redox fronts and the all-important interface to be objectively identified. Transported lateritic components can provide vectors to mineralisation in depositional regimes. Palaeomagnetic and new radiometric methods which date individual phases of the regolith provide evidence of different episodes, each characterised by different geochemical dispersion patterns in transported regolith. Along with lateritic residuum, calcrete is prime sampling medium. Calcrete is probably enriched in gold through physical and biological processes, rather than straight chemical processes. In South Australia, the lowermost calcrete layer buried within the depositional regime, especially where it lies directly over the silcrete layer at the buried interface, is the desired sampling medium. Certain gum trees, with deep roots in transported regolith have been shown to record anomalous values of gold and basemetals in leaves, twigs and bark. Anomalous metals in acid-sulfate soil seeps can also provide a window through sedimentary cover in respect of mineralisation in the basement. A number of Yilgarn occurrences of gold anomalies in transported cover, strongly infer hydromorphic and biological mobilisation of gold. This inference is supported by micro-analyses of regolith mineral hosts in hardpans and mottled sediments, which show gold and pathfinder elements prefer to reside in goethite and specific types of clay minerals. This creates anomalies in specific mineral phases. However the inference that that these are sites of mobile or labile metal ions remains enigmatic. Similarly there is inconclusive evidence that selective extractions will provide an anomaly not otherwise detected by conventional total dissolution methods. Hydrogeochemistry is a promising exploration tool for basemetal exploration. The importance of microbes in both the dissolution and precipitation of gold in the Australian regolith is demonstrated. We are on the verge of identifying the functional gene sequence of individual active microbes. A consideration of possible mechanisms for creating anomalies in soils above transported regolith, presents difficulties in facilitating upward movement of ions from the watertable to the surface. Perhaps the best avenues of research lies with surrogate soil gases, and biotic transfers.

Jan 1, 2004

By Hughes J. C

THE smelting plant consists of five large furnaces operating in the treatment of current flintered material, and one small furnace operating periodically in the treatment of copper dross and antimonial slag produced in the lead-refining process.he following table supplies the leading dimensions and details of the large furnaces:-(a) Crucible - Dimensions 17 ft. 2 in. long x 4 ft. wide x 2 ft. 3 in deep. Capacity - 30 tons lead. Class of lining - firebrick. No. firebricks required - 3000.(b) Crucible Tank - Dimensions 20 ft. 6in. long x 10 it. 6 in. Wide x 4 ft. 3 in. deep. Material - 1/2 in. mild steel.(0) Jackets - Dimensions 6 ft. long x 19 in. wide x 6in. thick. Material - Cast-iron. Average life - 2 years. Number per side - 11, with 13-in. bosh. Number per end - 3, with 9-in. bosh.

Jan 1, 1922

In the pursuit of commercial solutions for environmental issues, individual problems are often identified, considered and resolved in isolation from other environmental matters and always at the end of the cycle û after the problem has been created. Inter-relationships are neglected if they are not seen to obviously impact on a specific problem and the issue at hand is plucked from the environmental landscape and dealt with in total isolation to all else. In a Zero Waste approach to environmental matters, all outputs are pursued as potential inputs. Industrial processes are viewed as a variation on natureÆs theme and opportunity pursued above all else. When viewed from this perspective, industry appears to have forgotten its origins. It has forgotten that it is principally about people. The juggernaut of global trade has forgotten that it is a small part of a big landscape and that its principal participants, people, cannot exist without healthy soil. Commercial activity in all parts of the world relies heavily on the ability of agriculture to produce the necessary inputs for industrial production. The care and nurturing of our soils is fundamental, not only to the survival of humanity, but also to the economic systems that support that humanity and to the industry which profits by it. Actual levels of domestic recycling in many countries around the world seldom reflect the 90 plus per cent desire to recycle recorded in surveys conducted by local authorities in almost every country. If the desire to recycle is far removed from the end result, why is it that the systems provided are so ineffective? It is obvious that what we do need is a recycling system that both engages and rewards the participant and stimulates the innate desire to support the environment. A recent trial in New South Wales, Australia, demonstrated that by giving individual households credits for recycling organic wastes, not only will contamination levels fall dramatically, but increased yields, improved soil structure, improved land values, reduced fertiliser costs and increased water use efficiency give the farmer good economic reasons for purchasing and applying quality composted product. By underpinning and securing the agricultural community, we secure the future of industry. The æCity to SoilÆ project linked the economic on-farm benefits of compost use with reduced contamination through the provision of rewards paid for by the purchase of product by the farmer.

Jan 1, 2006

By J Vann

Mineral Resource and Ore Reserve estimation is a challenging and demanding field, requiring application of professional knowledge, skill and experience of the highest order. If the many potential pitfalls are to be avoided, however, there are two other requirements which are of equal, if not greater, importance:good communication, and common sense. Estimation of Mineral Resources and particularly of Ore Reserves is almost always a team effort, involving a number of disciplines. Good teamwork requires good communication, both between team members and between the team and other parties having an interest in the process. Breakdown in these lines of communication can have far reaching effects on the project under consideration. The need to use common sense during a Resource or Reserve estimation exercise would seem to be self-evident. It is surprising, however, how often rigid adherence to procedures and methods prevails at the expense of clear thinking, usually with adverse and sometimes fatal effects on the project under consideration. This has become increasingly true as computerised methods have assumed a central role in Resource/Reserve estimation. The critical question that estimators should ask themselves at all stages of the process is: æIs what is being done sensible given the data available, what is known of this deposit and the purpose of the exercise?Æ

Jan 1, 1999

Reverse sensitivity is a critical issue for all extractive activities. Extractive industries can only establish in the location of the particular resource sought to be extracted. Avoiding a location near sensitive activities (such as residential activities) may, therefore, be more difficult for extractive industries, than for other industry (such as dairy factories).   This paper focuses on the following matters: +        principles to be derived from case law, +       district and regional council approaches managing reverse sensitivity effects, and +        avoiding, remedying or mitigating reverse sensitivity effects in the future.

Jan 1, 2006

Mr. President, Ladies and Gentlemen, it gives me great pleasure to welcome you, on behalf of the Council and Administration, to this University and extend to you our very best wishes for a most successful and stimulating symposium. We as a College of the University of N.S.W. were always proud of the excellent support we received from your Institute members and the close association that existed between our organisations. Now we have matured into the University of Wollongong and have to stand on our own feet, we will need all the support we can get from such bodies as yours to ensure that we are not only producing graduates but are also playing a vital role in the community. Although there is no planning for a school of Mining Engineering in the near future, we do look forward to this being a viable proposition eventually and we will then be able to offer to your Institute wider facilities for your activities and ones which will embrace both the Mining and Metallurgy phases. Thank you Mr. President.

Jan 1, 1975

The Kwademen Au deposit was discovered in 1977- 1978 following a regional geochemical survey carried out as part of a UNDP (United Nations Development Programme) and BUMIGEB (Bureau des Mines et de la Geologie du Burkina) mineral exploration programme. The climate in Burkina Faso is rather dry, with markedly seasonal rainfall averaging 800 mm pa in the Kwademen project area. The relief is low and the drainage poorly developed, so that soil sampling was preferred to stream sediment sampling. Rocks have been subjected to deep lateritic weathering, so that they are transformed into a mixture of Fe-oxides and kaolinite over depths varying between 30 and 40 m. At the regional stage, soil samples (30-40 cm depth) were collected a a 300 x 500 m grid. The Kwademen deposit was indicated by Cu, Zn, Mo and Au anomalies. Subsequently, an area of 9.2 km2 was covered by a detailed geochemical survey by soil (100 x 50 m) and auger sampling. The regional anomaly was fully confirmed, and subsequent drilling intersected mineralized ore shoots, justifying the establishment of an evaluation project led by the U.N.R.F. (United Nations Revolving Fund) in 1983- 1985.

Jan 1, 1988

Any future developer of underground mining on the Bendigo goldfield will need to understand the unique geology and gold occurrence of this field. The development and sloping system employed will be primarily designed around these unique features. Modern techniques and equipment used in narrow vein mining will be applicable in this situation.The purpose of this paper is to examine the important geological features of the field as well as the known historical occurrences of the type of gold deposition in the ore bodies. This information will point to a system of development and extraction which will accommodate these features.

Jan 1, 1993

The Mount Morgan eopper-gold orebody is contained within a series of Mid-Devonian volcanics which occurs as a roof pendant within Permian granite. The ore minerals comprise pyrite, chalcopyrite, and local aggregations of magnetite and pyrrhotite. Silver-rich gold (electrum) is disseminated through the ore usually in ultrafine to sub-microscopic dimensions. Accessory minerals include marcasite, digenite, chalcocite, covellite, sphalerite, bismuthinite, molybdenite, calaverite, petzite, and cassiterite.Very minor accessories include cubanite, tetrahedrite, galena, arsenopyrite, hematiIe, goethite, and rutile. The gangue minerals are quartz, predominantly, with minor amounts of chlorite and sericite.Study of microtextures of a representative suite of specimens from Mount Morgan does not reveal any criteria indicative of metasomatic replacement but does show, in the case of pyrite, evidence strongly suggestive of annealing recrystallization. Other textures in pyrite indicate porphyroblastic growth of the iron sulphide.It is inferred that the Mount Morgan orebody is genetically related to the volcanic rocks and was later contact metamorphosed by the intrusive granite or by the series of intermediate to basic dykes that transect inmine area. On this basis the Mount Morgan orebody would be a contact metamorphosed volcanic hydrothermal deposit emplaced, according to recent studies, along a pipe-like zone of brecciation.

Jan 1, 1967

This paper summarises the influence of slurry rheology on the grinding throughput of batch laboratory and continuous plant-scale mills operating in open and closed circuit configurations. The results of controlled changes in percent solids, particle size, slurry temperature, and viscosity control chemicals are demonstrated. An underlying rheological explanation of the above factors is offered which involves tying the specific rates of breakage that are occurring in the mill with the specific rheological character that the slurry is exhibiting at any given set of operating conditions. Some industrial scale operating guidelines are presented which have proven useful in increasing the net pro- duction capability of grinding circuits.

Jan 1, 1978

Gas dynamic phenomena, particularly instantaneous outbursts of coal and gas are problems experienced in gassy, highly stressed coal, both usually the result of depth. Diff- erent mining geometries present different opportunities for seam gas to escape, starting from the virgin condition unaffected by mining and ending with the mining of the coal. The mining of the coal varies from entering a virgin seam cross-measure, heading out into virgin seam, advancing longwall faces into virgin seam and extracting developed blocks from large longwall retreating blocks to small pillars. Each method has its particular gass- iness patterns and particular stress patterns, both changing to some extent with time, and changing as mining progresses. Geological structural anomalies are the cause of gas and stress anomalies, causing in turn greater gas and stress manifestations. Pre-drainage of gas from the working seam not only degasifies the coal but causes it to shrink and so may affect stress as well as gas patterns. Unfortunately prior degasification is not all benefit, and there are some d13- advantages to its use. Also although it is possible to degasify places ahead, gassiness will return if drainage holes are shut down or sealed up and other deleterious aspects may be induced. Research should continue into the problem of instantaneous outbursts of coal and Gas.

Jan 1, 1986

Incidental to the progress of a geological survey of the Kalgoorlie goldfield during 1927 - 1928 a number of specimens of telluride minerals were obtained, chiefly with the help of Mr F G Brinsden, general manager of the South Kalgoorlie mine, and Mr Ernest Williams, general manager of the Boulder Perseverance mine. This collection was supplemented by a number of small specimens, including the rare copper telluride, which were collected and preserved from the Kalgoorlie mine by Mr A E Paton, and also by a few miscellaneous specimens from the collection of MrS F C Cook, of the Palace Hotel, Kalgoorlie.An extensive knowledge of the rare tellurium-bearing minerals was compiled during the last century from occurrences in Transylvania and Colorado. The recognition of different species has been based on chemical analyses and crystallographic measurements. In a few species there has been an absence of crystalline form, and these, together with the discoveries in this century of rickardite and 'weissite', muthmannite and empressite, have depended chiefly on the chemical analysis for identification. On the other hand, the crystalline form of nagyagite and stiitzite has been described in detail, while their precise chemical formulae were doubtfully defined.The announcement of the occurrence of tellurides at Kalgoorlie by A G Holroyd in the Kalgoorlie Mine on 29 May 1896, followed by their discovery in comparative abundance, stimulated the further study of these minerals. In this locality there is a general absence of well-formed crystals, and the knowledge gained has been confined to the record and description of previously known, but exceedingly rare, species.No new species has been recorded, but the intimate association of various species resulted in early description of two supposedly new species, kalgoorlite and coolgardite. These have been discredited since the investigation by L J Spencer in 1903, based on a collection of specimens donated to the British Museum.Spencer's list of species at Kalgoorlie comprises calaverite, sylvanite (or krennnerite), petzite, coloradoite, 'and altaite, and does not include hessite, previously mentioned by Krusch. In 1912 melonite and a copper telluride were added by J A Thomson and the presence of hessite confirmed. In 1912 there also appeared a full and detailed account by E S Simpson on behalf of the WA Geological Survey, which embraced his earlier notes on the tellurides, and which represents the state of our knowledge of the Kalgoorlie minerals, practically as far as can be attained without the use of the reflecting microscope.The position has been stationary for about 18 years, and it was thought. that the best use to which the present collection of tellurides could be devoted was an attempt by mineragraphic methods to study the mineral relationships, not only of the tellurides among themselves, but also to gold and other associated minerals. The precise mineral content and relationships become a factor of added importance with the development of flotation methods of treatment at Kalgoorlie.Moreover, the study would supplement the description of the ore deposits of the Boulder Belt that has recently been published.

Jan 1, 1994

By A Kleinitz, J Halilovic, K Trappitt

Mine operators use grade control to determine the destination of each block of material in the mine. In polymetallic mines, grades are best expressed in dollars: the Net Smelter Return, NSR, per tonne. To estimate NSRs, geologists working on grade control develop models for each geometallurgical domain in the mine. These models may incorporate observations on the mineralogy and grain sizes of the material being examined. The site’s mill operators contribute to the models by providing geologists with statistical analyses that relate assay results and mineralogical compositions to metallurgical parameters, such as the rates of recovery of each economic metal to each of the concentrates produced, and the compositions of those concentrates. The team responsible for sales and marketing of the site’s products contributes to the NSR models by providing details of the costs of shipping concentrates to smelters and refineries; and by providing figures that are specified in the smelter contracts, such as the payability of the metals in each concentrate and the fees charged by the smelter. The mill operators also provide, for the NSR models, equations to estimate the rates of recovery of deleterious materials to each concentrate. Deleterious materials comprise mostly halogens and amphoteric elements, both of which reduce the efficiency of smelters. Furthermore, deleterious materials such as antimony and arsenic may be poisonous to people and to the environment. The sales and marketing team provide specifics of the penalties that smelters impose upon deleterious materials. These penalties may reduce NSRs by tens of percent, possibly to levels below the cut-off grade. Thus, in the blocks that are subject to grade control, mine geologists monitor not only the concentrations of economic metals, but also the presence and abundance of deleterious materials. The preparation and maintenance of models, to estimate NSRs and to assess changes in the levels of potentially toxic materials to be mined, requires close and continuing consultation between corporate departments. There must be strong communication of mine geologists with the mill operators; with the people who market the mine’s concentrates; and, should there be a risk of encountering toxic levels of deleterious materials, with the mine’s health, safety and environmental officers. This co-operation could require radical changes in the structure of many organisations. However, experience suggests that such changes can significantly improve the profitability of a mine.

Mar 22, 2022

By McKay AD

The bulk of Australia's uranium resour- ces was delineated in the last 18 years when a total of $563 million (1984 dollar values) was spent on uranium exploration. Australia's share of the low-cost Reasonably Assured Re- sources in the World Outside the Centrally Planned Economies Area (WOCA) increased from 1.5% in 1967 to 29% by the end of 1984 and its share of the low-cost Estimated Additional Resources (Category I) then stood at 25%. As of December 1984, Australia's uranium resour- ces were estimated by the BMR to be: Cost range US$80/kg U (US$30/lb U301) Reasonably Assured Resources 463 000 t U Estimated Additional Resources(I) 251 000 t U Cost range US$80-130/kg U (US$30-50/lb U308) Reasonably Assured Resources 63 000 t U Estimated Additional Resources(I) 126 000 t U The increases in Australia's resources was sustained by a group of large and rela- tively high-grade deposits which were disco- vered during the period 1969 to 1975. Austra- lia's share of the low-cost resources was also enhanced by a contraction of WOCA's low-cost resource base due to escalation of production costs for smaller low-grade deposits. Most of Australia's uranium resources are contained in the Proterozoic unconformity- type deposits of the Alligator Rivers uranium field and the stratabound deposit at Olympic Dam on the Stuart Shelf. Most of the remain- der of Australia's uranium resources is con- tained in calcrete-type deposits. Less than 10% of Australia's uranium resources are in sandstone-type deposits. Total Australian production to the end of 1984 amounted to 26 241 t U, representing 3.4% of WOCA's cumulative production. Aus- tralia's share of WOCA's annual production has steadily increased from 1.3% in 1977 to 11.2% in 1984 (4390 t U). The increases in Austra- lian production took place in the face of reductions of production in WOCA countries, principally the US, from a record level of 43 988 t U in 1980 to about 39 000 t U in 1984. New low-cost production centres, mainly in Australia and Canada, have partly compen- sated the decline in US production. The Department of Resources and Energy (1985) reported that Australian exports of yellowcake are expected to reach 10 000 t U308 (8480 t U) by 1993/94, representing an in- crease of about 13% oer annum.

Jan 1, 1986

Mineral Processing Education in China

Sep 13, 2010

LIST OF CONTENTSAbstractIntroductionSelected Sections of the Broken Hill LodeLocality PlansPetrology1. Zinc Corporation Mine: DDH. 5.98, section 30, No. 26 level2. Zinc Corporation Mine: DDH. 838, section 30, No. 13 level3. Broken Hill Sonth Mine: 60 ft. cont01(r above 1170 ft. level4. Broken Hill South Mine : No. 7 shaft section, 1370 ft. levelOrigin of garnet sandstone5. Barrier Central Pty. Ltd.: DDH. tJ.93, Block 136. North Broken Hill Ltd.: Junction mine, DDH. 602, No. 10 level7. North Broken Hill Ltd.: Jnnction mine, DDH. 588, No. 11 level8. North Broken Hill Ltd.: North mine, DDH. through Southern ore body, 3370 ft. level9. North Broken Hill Ltd.: North mine, Northern ore body above 2300 ft. level(a) Southern end, section 27, 77 ft. above rails(b) Northern end, section 30, 6.9 ft. above rails(c) Miscellaneons samples, sections 27 and 28Relative time of ore depositionSericitizntionStructural significance of sericitizationGCLhnite OrthoclaseApatite GarnetManganese SilicatesAlteration of manganese silicatesRelation of zinc and lead to the silicatesZinc in manganese-bearing silicatesLead in potassium and lime silicates and apatite

Jan 1, 1959

By Kareise G. J, Leung K

The McArthur River (HYC) deposit, located in the Northern Territory of Australia, was discovered by Mt Isa Mines Limited geologists in 1955. It is one of the largest sedimentary stratiform zinc-lead-silver deposits known. Previous attempts to exploit the deposit have been thwarted by its geographical location, the capital expenditure required to establish an operation and the fine-grained nature of the mineralisation. The steeply dipping western margin of the deposit is covered by up to 25 m of overburden, and lies beneath the McArthur River and its flood plain. Dips are eastward, with the eastern edge of the deposit at a depth of about 400 m below the surface. The average thickness of the deposit is 55 m, and it covers an area of about 1.8 by 1.3 km. Seven stratiform orebodies are interbedded with sedimentary breccia, tuff and poorly mineralised siltstone. Mineralisation consists of finely intergrown sphalerite and galena, hosted by pyritic siltstone of the middle Proterozoic McArthur Group. Selective underground mining of the lower orebodies will extract more than one million tonnes of ore per annum. The dip of the mineralisation demands that mining will be by way of apparent dip room and pillar. Declines will provide access and haulage, and wherever possible development will be in ore. Initially, haulage will be by trackless diesel powered trucks, but these will be replaced by a conveyer system. A single zinc-lead-silver concentrate will be produced from a simple flowsheet. This flowsheet has been developed in the laboratory and demonstrated during an extensive pilot plant campaign. A single stage SAG mill will be utilised to grind the ore down to a P80 = 45 ltm (80 per cent of particles passing 45 ¦rn. Conventional flotation cells will produce a single rougher concentrate that will be reground to No

Jan 1, 1993

CONTENTSThe significance of values givenINTRODUCTIONTHE ORE1. DATA SECURED FROM THE MILLING PLANT AS OPERATING BETWEEN 1938 AND 1942(a) Mill Recoveries(b) Mill Flow Sheet(c) Scheelite-Garnet Association(d) Detailed Examination of Mill Performance during 1942Crushing UnitsCoarse Rolls DischargeFine Rolls DischargeFeed to Huntington MillsFinal Ground ProductProduction of -200-mesh Scheelite SlimeSummary of Information on Crushing and Grinding Circuit(e) Detailed Examination of Mill Performance During 1942Concentrating UnitsLocation and Nature of Scheelite LossesSize Distribution of Scheelite LossesDistributor Spigot ProductsSummary of Information on Concentration Circuit(f) Detailed Examination of Mill Performance During 1942 Gravity Plant Feed2. EXAMINATION OF MINE SAMPLES TAKEN DURING 1942(a) Introduction(b) Nature of the Ore(c) Sampling of Mill Feed(d) Testing Technique(e) Minus 1/8-inch Ores-Naturally Broken Fractions(f) Recoveries from Plus 1/8-inch Fractions-Crushed to Minus 1/8-lnch(g) Probable Recoveries Obtainable from Weathered Ores140 Contour120 Contour90 Contour(h) Examination of an Ore Sample from the 90-foot Adit(i) Run-of-Mine Ore(j) Evidence of Maximum Sizes of Scheelfte Present in Run-of- Mine Ore(k) Summary of Information on Liberation and Recovery from the Ores as Mined in 1942 and from the Mill Samples

Jan 1, 1944

By Gregg PEH, Horne D, Bolan N, Stewart RB

The Tui mine site is situated on the NW flank of Mt. Te Aroha, at approximately 400 m altitude. During underground mining operations two lead-copper-zinc ore bodies were exploited and processed on site. The legacy of the mining operation is a barren dam containing over 100,000 m3 of sulphide-rich tailings. The Tui mine site is arguably the worst case of environmental degradation resulting from past mining activity in New Zealand. Although the impacted area (approximately 4 ha) is extremely small by international standards, acid mine drainage (AMD) emanating from the abandoned tailings dam and mine adits has severely contaminated local streams and prevented natural plant recolonisation of the site for more than 20 years.

Jan 1, 1995

By Bush P. R, Hale M, Dixon C. J, Wheatley M. R

Barium anomalies in drainage sediments can act as indicators of barite mineralization and path- finders for lead-zinc mineralization. Their detection in an arid climate has been investigated in two areas of Saudi Arabia. At Rabigh, 150 km north of Jeddah, barium anomalies found in wadi sediments reflect barite veins which occupy Tertiary faults in Precambrian metavolcanics and granodiorite. In the Wadi ad Dawasir area, 650 km east of Jeddah, the sediments of wadis draining the Jabal Tuwayq escarpment have been found to contain anomalous concentrations of barium derived from diagenetic barite in the Sudair formation siltstones and shales. Barium dispersion in these wadis is predominantly clastic. Near to the source rocks, barium occurs in relatively coarse grains of barite. Owing to the three well-developed cleavages of barite, its crystals readily break into cleavage flakes during fluvial transport in flash floods; as a result, the longest anomalous dispersion trains are found in the 250 to 600 um fraction. Wadi sediments finer than 250 um have relatively constant and low barium contents, being dominantly composed of windblown sand.

Jan 1, 1988