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By Gupta R. C

Syria has about 500 million ton deposit of minerals having 34 per cent iron content with alumina and silica as major impurities. Efforts were made to see the feasibility of concentration by four different methods involving washing, high intensity magnetic separation, reduction roasting and magnetic separation and acid leaching technique. It was observed that the reduction roasting with magnetic separation yields a concentrate with high iron (62.3 per cent) content without requiring water which is a scarce raw material in the region. The paper concludes that the detailed study may be made following this route to optimise the process Parameters.

Jan 1, 1999

Laboratory electrical resistivity measurements of rocks are reviewed. Inductive and galvanic methods are discussed together with the ten important experimental factors which should be considered in an investigation.These experimental factors are electrodes, sample preparation, measurement errors, temporal current variations, current density, frequency, electrolyte composition, electrolyte saturation, pressure, and temperature.

Jan 1, 1969

By Sharpin P. C

The countercurrent gas-solid heat transfer during the drying of brown coal briquettes in the pilot carbonization plant at Morwell has been analysed and theoretical gas and solid temperature distributions through the drier have been calculated. Although the calculations rest on several simplifying assumptions, the theoretical temperature distributions compare well with those observed in practical operation. Valuable conclusions are reached as to the effects of changes in drier operating conditions on the rate of drying of the briquettes which controls the strength of the char produced. The analysis shows why a limitation was reached in the improvement of char strength in the pilot plant in 1961 due to the performance of the drier and a prediction is made of a way in which the limitation could be overcome.

Jan 1, 1966

By Lyon R. J P

The quartz-cassiterite-wolfram veins at the Aberfoyle Tin Mine, north-eastern Tasmania, form a sheeted zone about 200 ft. wide and 1,600 ft. long in slightly contact metamorphosed shales, slates and greywackes, and are associated with a cupola of aplitic granite whose top is about 1,050 ft. below the present surface. Economic mineralization persists from the surface down to a vertical depth of 1,050 ft. to 1,100 ft., dying away in the vicinity of the cupola. Down to the 9-level there is a progressive increase in wolfram content of the veins, and a decline in cassiterite content, with increasing depth.The veins are banded or zoned, with a seivedge of muscovite on the wall. Cassiterite, wolfram and sphalerite occur inside the selvedges, projecting into a core of quartz of varying width. Other sulphides form the central part of some narrow veins, or occur as clots in the quartz. The general sequence of deposition of the ore minerals was: (1) cassiterite, wolfram; (2) arsenopyrite, pyrite, molybdenite; (3) pyrrhotite (in part); (4) blende-group minerals-chalcopyrite, sphalerite, stannite, pyrrhotite (in part)-as solid solutions; (5) galena, tetrahedrite, matildite, native bismuth, scheelite; (6) marcasite and secondary pyrite, magnetite and hematite. The sequence of deposition of the gangue minerals was: (1) fluorine-bearing minerals-muscovite topaz, apatite, triplite, fluorite-more or less contemporaneous with the cassiterite and wolfram;' (2) quartz-contemporaneous with the earlier sulphides; (3) carbonates--contemporaneous with the later sulphides. The stages overlapped somewhat.The composition of the sphalerite and heat treatment experiments with the solid solutions indicate that the blende-group sulphides were deposited at about 6000 C., and cooled rapidly, so that unmixing of the solid solutions was arrested. This accords with the likelihood that the country rock temperature was not above 2000 C. Annealing experiments at between 3500 C. and 6000 C. led to further precipitation from solid solution at the lower temperatures, and to significant segregation by solid diffusion within, a week, indicating that both deposition and cooling of the ore were rapid processes-completed in a matter of days. Since the mineralizing solutions must have lost some heat during...

Jan 1, 1957

In a previous paper the writer dealt -with the jasper bar formations and their relationship to the structural geology of older pre-Cambrian rocks in the goldfields districts of Western Australia (24). He has pointed out in this ahd other papers that jasper bars, or banded iron formations, banded hematite or ,magnetite quartzites, jaspilites and related banded ferruginous or non-ferruginous cherts, occur in abundan'ce in the Older Greenstone Series of Western Australia (22), (24), (26). They are considered to represent special forms of banded ferruginous sediments, and are usually fpund in the field interbedded with more or less metamorphosed pasaltic 01' andesitic lavas and tuffs, now amphibolites, together with occasional thin bands of normal pelitic sediments, which go to make up a large proportion of the Older Greenstones in thfs State (26).Great thicknesses of fiat-bedded ]:landed ferruginous cherts are also found associated with cherty' carbonate rocks; quartzites, shales and thin-bedded dolomite whicIi constit'ute the Nullagine (Pl'oterozoic) system in the northwest of Western Australia. In the Hamersley Range district these banded ferruginous chert beds are the hosts of important deposits of blue amphibole asbestos.In the paper mentioned above brief reference was> made to the importance, of geological structure in relation to economic geology, particularly in the goldfields regions of Western Australia, and it was shown that jasper bars may have an important role in the study of 'the structural geology of many of these regions. Of possibly more immediate economic importance is the part that these rocks play, both directly and indirectly, as host rocks for mineral deposits-the chief of Which are gold, iron ores, blue asbestos, and manganese ores. The blue asbestos bearing banded iron formations mentioned above are confined to the younger pre-Cambrian Nullagine formations. They have been described in detail elsewhere (23). In this paper it is proposed to discuss the economic geology of the jasper bars found in the older pre-Cambrian series.The jasper 'bars have in themselves little or no intrinsic value except perhaps some of the more highly coloured and banded varieties which may be utilised for ornamental and decorative purposes. Probably the best known of such varieties is the so-called "marble bar;" a belt of, strikingly coloured banded chert occurring just south and west of the famous town of that name (see Fig. 1t). This consists of a hard, very fine, even-grained rock with alternate individual stripes varying from the thickness of a sheet of paper up to an inch or more in width, and ranging in colour from clear white to yellow, from various shades of pink to brilliant...

Jan 1, 1943

Some of the problems associated with drill core evaluation of alluvial tin deposits and correlation with plant-scale recovery are discussed. Panning churn-drill cores on site tends to undervalue such deposits because of failure to recover completely all the available liberated cassiterite, and secondary gravity processing may also fail to give an accurate determination of potentially recoverable tin. However, by using a combination of heavy liquid separations, x-ray fluorescence analysis for Sn, and normal methods of reflected and transmitted polarized light microscopy, a quantitative assessment of alluvial material can be carried- out. The information obtained may include the liberation characteristics and distribution with size of the cassiterite, the nature and quantities of the various gangue minerals, and the amount of potentially recoverable cassiterite in the material as compared with the amount locked with light gangue minerals and hence difficult or impossible to recover. In addition, an analysis of the efficiencies of the various gravity processes, such as panning, jigging, and tabling, used to determine "recoverable tin" in the alluvial material, can be carried out. A detailed example is given of this type of investigation, in which an assessment was made of a churn-drill core from Uncia, Bolivia.

Jan 1, 1970

By Zwaan J, Kepa J

Ok Tedi mine has become one of the major copper producers in the world. In the process of becoming of age, it overcame the challenges of operating in a locality which is young in geological terms, experiences very high rainfall and has a topography which gives rise to frequent landslides. This paper discusses some of the geological, mine and geotechnical engin- eering aspects of the Mt Fubilan ore deposit.

Jan 1, 1991

By Weber P, Sneyd S

The total world steel production in 1998 amounted to approximately 780 000 000 t. The share of electric steelmaking was in the range of 35 per cent and is expected to increase further to over 40 per cent of the world's production within the next ten years. As electric steelmaking is primarily based on the use of scrap and as it is progressing more and more into higher steel grades the need for low-residual metallics will become increasingly important. Consequently, the demand for scrap substitute material will increase, reflected in the world wide spate of interest for DRI (Direct Reduced Iron) and HBI (Hot Briquetted Iron). The increased significance of DRI/HBI as a substitute for steel scrap has obviously emanated also from its comparatively lower and more predictable costs per ton and definable chemistry. In 1998 already 37 million tons of DRI/HBI were globally produced.

Jan 1, 1999

By W J. Rankin

A study was carried out to compare the environmental impacts of a number of process routes for lead and zinc metal production from sulphide ores using Life Cycle Assessment methodology and based on average industry data derived from the literature. The processes investigated were:blast furnace production of lead; Imperial Smelting Process for lead and zinc production; and electrowinning of zinc with the mining and mineral processing stages common to all three routes. The effect of a number of process variables, namely ore grade, fuel source for electricity generation and efficiency of generation, on the environmental impacts was also examined. The environmental impact categories considered in the study were:total (or full cycle) energy consumption; Global Warming Potential (GWP); and Acidification Potential (AP). The results of the study show that when produced separately, zinc production is more than twice as energy intensive as lead production (viz 48 and 20 MJ/kg respectively), however when produced jointly by the Imperial Smelting process, the energy intensity of the two metals is not all that dissimilar (viz 36 and 32 MJ/kg respectively). The metal production and refining stage was found to make the greatest contribution to the overall environmental impacts for all three processes. The study also highlighted the importance of taking a life cycle approach when comparing the environmental impacts of different processes.

Jan 1, 2002

This Institute, by nature of its charter, draws on various persons in the mining and metallurgical world of Australasia for its President from year to year, and consequently when the presidential address is given by one of these people the topic. which they generally select is a topic to which they are accustomed and on which they are able to speak with authority.As most of you know, my prime object in life has been concerned with steelmaking, so tonight you can steel yourself to the thought that you are going to be spoken to about steelmaking.Even if that were not the case, and were I not particularly interested in steelmaking, I think it would be appropriate to look at steelmaking in a broad sense on a basis of pure metallurgical interest, because the steel industry is going through as big a revolution today as it went through something over one hundred years ago when Bessemer made a theory become a fact.Bessemer, and as the Americans prefer to think Kelly, separately conceived the idea of blowing cold air through molten pig iron, and, contrary to the then general belief, this did not result in cooling of the metal but succeeded rather in heating it, and in burning out of the rather crude pig iron the impurities which prevented it from becoming a ductile metal.For many years before this, steel had been made in a very small painstaking way by what was known as the crucible process. Benjamin Huntsman is credited with having developed the crucible steel making process to a stage where it could make a reliable and trustworthy product, but he...

Jan 1, 1961

By W Herrmann, R R. Large

Volcanic-hosted massive sulfide (VHMS) deposits in ancient, submarine volcanic belts of Australia include mound, lens and sheet-style Zn-rich polymetallic deposits, massive and disseminated pyritic Cu-Au deposits and disseminated, stratabound Au-only deposits. Variation in morphologies, metal ratios, volcanic environments and alteration features indicates there exists a spectrum of deposits from the classic VHMS model, to hybrids between VHMS-porphyry Cu and VHMS-epithermal end members. Zn-rich, polymetallic deposits form eitheron, or just below, the seafloor, whereas the Cu-Au and Au-only deposits form sub-seafloor by replacement of specific volcanic lithologies. Alteration zoned outwards from quartz -> chlorite -> sericite ¦ carbonate is typical of VHMS deposits across the spectrum. Quartz and carbonate alteration is dominant in the Au-only systems,chlorite alteration is commonly developed close to Cu-rich ores, and sericite and carbonate alteration zones are well developed in the stratiform Zn-rich ores. The most useful geochemical vectors for Zn-rich ores are the alteration index [AI=100(MgO + K2O)/(MgO + K2O + CaO + Na2O)], the chlorite-carbonate-pyrite index [CCPI=100(MgO + FeO)/(MgO + FeO + K2O + Na2O)], Mn content of carbonate, Mg/(Mg+Fe) ratio of chlorite,whole-rock Tl, Sb and Ba/Sr ratio, S34S of pyrite, and whole-rock S18O. The most useful vectors for pyritic Cu-Au ores are AI, CCPI, S/Na2O ratio, Na content of white mica, and Fe content of carbonate.

Jan 1, 2002

The metallogenic map of New Zealand shows the distribution of metallic mineral deposits, according to type and size, in relation to their geological setting. The major purpose of the map and accompanying 200-page monograph is to summarise the distribution, modes of occurrence and origins of the metallic mineral deposits of New Zealand. The map demonstrates the prospectivity of New Zealand for metallic minerals, particularly gold, silver, iron, and titanium. Information on each deposit is summarised in index tables based on major geotectonic units or deposit/commodity type. The mineral deposits are arranged and discussed in relation to tectonostratigraphic and tectonomagmatic units or terranes, under broad geotectonic divisions of the Paleozoic to Mesozoic Western Province, the late Paleozoic to Mesozoic Eastern Province, the mid Cretaceous to early Tertiary rifting phase, and the late Cenozoic Kaikoura Orogen. Regions or areas of marked concentration of mineralisation are recognised as metallogenic subprovinces or districts, namely: eastern Northland (Hg), the Hauraki Goldfield (epithermal Au-Ag-Pb-Zn-Cu), the west coast of the North Island (shoreline placer Fe), east Nelson (podiform Cr), west Nelson (porphyry Mo), the West Coast of the South Island (shoreline placer Ti), west Nelson-Westland (placer Au), Reefton (mesothermal Au-quartz veins), and Otago (placer Au and mesothermal Au-W quartz veins).

Jan 1, 1993

Maori economic development still remains an enigma to many people some 157 years after the signing of the Treaty of Waitangi. It has only been in the last decade as a result of increasing pressures from Maori to recognize and settle grievances arising from the Treaty and the resulting compensation issues that "mainstream" has begun to sit up and take notice. While Treaty settlements such as the Tainui, Ngai Tahu and Fisheries settlements have gained prominence as a source of economic potential for Maori, there are significant existing assets owned by Maori worth an estimated $4.6 billion that add an exciting new dimension to Maori contribution to New Zealand's enterprise economy.   Despite the fact that many claims have yet to be resolved, Maori are clearly shifting from grievance to development mode as evidenced by their focus on capacity building through education, strategic alliances nationally and internationally and the significant growth of nett asset worth of Maori interests in a number of industry sectors.   In essence, Maori provide a large un-tapped economic potential in New Zealand. The years of relative economic obscurity appear to have wetted their appetite for positive growth and economic independence. Given current trends, it would not be unrealistic to expect the asset base of Maori to double in value over the next decade and to see the emergence of Maori owned Corporates not only within the New Zealand economy but also trading actively in the global market place.

Jan 1, 1997

One of the chief drawbacks to Bendigo mining always has been the difficulty of draining the mines in an equitable manner, so that each company or mine owner bears the properly share. The trouble seems to have been apparent on this field since the diggings were discovered. One mine would push on more expeditiously than its neighbour in looking for the precious metal and sink its shaft, whilst those in the vicinity would simply potter about, and discontinue sinking until gold was struck in the deeper ground, and: then they would go ahead, start sinking, while the pioneer would have to pump all or most of their water. This sort of thing continued here for years until the leases were worked down to the very deep ground and the water became such a b.urden on those companies that had deep shafts, that first one stopped hauiing and then others; with the result that over 1000 feet of water was allowed to accumulate on the New Chum line. lt appeared that if something were not done the whole of the main line of reef in the Bendigo district would be at a standstill, when a scheme was formulated and handed to Mr. Lansell, who, with other gentlemen, took the matter up, and at the present time all the mines on that particular portion of reef are in full work and the water all bailed out.lt is this scheme that I am requested to place before you and also to give you the details of the work done since its adoption.

Jan 1, 1902

By Lee T. J

The area, A, under a gamma-ray log that passes through a horizontal bed given by: A = gl/k. Here is the equivalent concentration of U3O8 in the body, l the thickness of the body, and k the calibration factor or sensitivityof the logger. The area is independent of the logging speed or logger time constant.This relationship, together with the first moment about the maximum of the log and its value there suflicient to determine the thickness, position of the centre of the bed from the log maximum and the concentration of U3O8.Numerical results obtained from artificial and field data show that the computed results arc as good as those obtained by methods such as the inverse filter technique and the iterative method. The present method yields results that arc easier to feed into an ore reserve data base.

Jan 1, 1981

By G F. Brent, R D. Hart, C Carr, F Felipe

In underground operations, where copper, gold and other metals are mined, the open stopes can be backfilled to stabilise surrounding workings. This fill may consist of tailings from the processing plant, usually mixed in slurry with a binder such as ordinary Portland cement (OPC). Extensive use is made of tailings in OPC-based paste fill, cemented hydraulic fill or cemented aggregate fill applications. A large underground operation such as the Mount Isa Copper Operations utilises over three million tonnes of backfill per annum. Geopolymers offer an alternative binder system with significant environmental advantages over OPC. Geopolymers are formed by polymerisation of aluminosilicate precursors in an alkali medium. They generally form products with superior strength characteristics as well as increased resistance to degradation, particularly under acidic conditions. Geopolymers have lower carbon dioxide emissions associated with their manufacture than OPC and offer further potential advantages, such as the use of less water and more waste materials. The application of geopolymers to weak material systems such as mine backfill has not been widely studied. The aims of this investigation were to assess a range of Australian mine process wastes for suitability as feedstocks in fill applications and to construct a range of these cemented minefills using a geopolymer binder. The physicochemical characteristics of each of the wastes are discussed as well as how they ultimately contribute to the geopolymer cement through direct replacement of OPC. Results from various tests on the candidate geopolymer fill formulations are presented and the potential of such fill formulations to replace OPC in mine backfilling operations is highlighted. The significant potential contribution to reducing greenhouse gas emissions from the use of geopolymer-based mine backfill across the industry is noted. Conversion of a single mine, such as the Mount Isa Copper Operations, is shown to match the reductions in greenhouse gas emissions due to the current total installed photovoltaic electricity generation capacity of Australia. A similar examination of wastes available to a gold mine could potentially yield new binders for use in established or new fill systems.

Jan 1, 2007

By P González, E Córdova, E Faundez

An integrated mine system must be capable of displaying and reporting valuable information that can be used to easily understand, manage and take action on the key parameters being reported.One of the key aspects of integration is the standardisation of the mine information up to a level capable of adapting the main characteristics of past projects at the mine and enforcing the same or higher standards for newer projects being developed.At the El Teniente mine, photogrammetry is used to map the advance of horizontal developments, and the constructed 3D representation of each face is then used by the geologists to obtain structural information about the areas being photographed.The mine realised that valuable mining information could also be extracted from the photogrammetry being applied, with three possible areas of development envisioned.The first area was creating a link between the developments being planned on a yearly and monthly basis and matching them with plan sections of the 3D developments of the system to account for any deviations.The second area was to use vertical sections of the 3D developments to estimate the overbreak of the excavations in different areas of the mine.The third area was the provision of a more detailed analysis of the sections so that they could provide information on the thickness of the shotcrete being applied.This paper presents the different alternatives being used and examines how the project is currently being developed and managed at the mine. It also looks at the challenges associated with implementing the reporting platform and the results being obtained.CITATION:Córdova, E, Benado, D, González, P and Faundez, E, 2016. Mine planning information from photogrammetry sources at the El Teniente Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 653–658 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

Suddenly, mining has been thrust into the limelight. It has a large image that casts its shadow over New Zealand. Is it any wonder that resistance has heightened and that an almost unprepared populous is currently struggling to protect the very land they hold dear. Next to the atomic bomb, mining has the demonstrated power to massively change the land and its side effects can pollute many miles beyond the operation. During the past year, New Zealand concern over the possible effects of the mining proposals has become acute. This was specially so in the areas of special environmental quality, such as the Coromandel, and here a very unhappy situation has arisen.

Jan 1, 1981

The purpose of this paper is to outline some aspects of the experimental worlr that has been carried out in the mineral dressing laboratory at M'ount. Morgan during recent years.The subject matter has been dealt with under the following headings:1. Comminution of various mill products.2. The application of sulphur dioxide as a flotation reagent.3. Heavy-media separation.4. Bulk flotation of sulphide ores.COMMINUTION OF VARIOUS MILL PRODUCTSThe following data were cbtained by processing fractions of reserve grade ore.Granular TailingIn Table 1 are shown the results of tests on material representative of average grade tailing. In the first test (H1 ) the granular tailing was floated as received and in the second test (Ha) the tailing was ground prior to flotation.

Jan 1, 1952

The outlook for suppliers of energy to the expanding economies of the Pacific Basin region is essentially positive, but particularly for exporters of high quality steam coal. This paper argues that economic growth in the Pacific Basin region has exceeded world economic growth for some years and that this will continue to be the case for the next decade at least. It looks briefly at the link between economic growth and energy demand and at the relationship between energy demand and the demand for electricity. Changing preferences in fuel mix for electrical generation in the region are noted and tentative forecasts made about variations in this mix. The pros and cons of various forms of fuel used to generate electricity are considered from the point of view of the consumer. Having concluded that steaming coal in particular is likely to become even more important as a generator of base load electricity, the paper looks at the opportunities this presents for exporters such as Australia, and touches on some factors that could prevent development of those opportunities. This paper will concentrate on electrical energy. For the purposes of this paper, the Pacific Basin refers essentially to Australia, New Zealand and the Asian countries bordering the Western Pacific. As a supplier, Siberia is not included because, although it has great potential, it is thought that problems of climate, infrastructure and political restructuring will delay the realisation of that potential until the next century. Although it deals with the Pacific Basin region, where many countries are industrialising rapidly from a predominantly agricultural base, it looks at the experience of mature industrial DECD economies where their experiences seem relevant.

Jan 1, 1990