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The Indonesian province of Papua is a remote jungle-clad region covering the western half of the mountainous island of New Guinea. Despite being relatively under-explored to this day,Papua is home to the greatest mineral success story of the 20th century. The Grasberg/Ertsberg minerals district atop the central dividing range contains the worldÆs largest reserve of both copper and gold (Freeport-McMoRan Copper and Gold, 2002). With large mines at Ok Tedi,Por gera and Lihir,and many well-delineated resources such as Frieda River,Wafi and Hidden Valley, neighbouring Papua New Guinea,the eastern half of New Guinea has enjoyed sustained exploration campaigns for gold and copper since the mid 1960s. The combined Grasberg and PNG exploration successes can be measured in terms of ounces of gold produced over the last decade versus available landmass,conf irming the island of New Guinea and surrounding islands as a world-class destination for gold explorers. Yet despite this obvious regional prospectivity and the profitability of the Grasberg operation, a sustained exploration effort in the Papua province in Indonesia has not been achieved. Periodic political constraints, poor infrastructure, high costs, operational challenges, social and environmental concerns and lack of immediate exploration success often impact exploration investment decisions. Accordingly a lesser number of mineral occurrences have been documented in Papua compared to those seen along tectonic strike in geologically similar Papua New Guinea.

Jan 1, 2004

By Onal G, Celik MS, Dogan MZ

Chromite tailings assaying 21.2 per cent Cr2O3 was upgraded to 48.7 per cent Cr2O3 at a recovery of 72.0 per cent using column flotation with a mixture of anionic collectors at pH 11. Electrokinetic methods were used to elucidate the mechanism of collector adsorption and correlate the findings with the optimum flotation conditions. Multivalent constituent ions such as Cr3+, A13+, Fe2+ and Mg2+ were found to adsorb on chromite surface and shift the zpc of chromite in the direction of oxide form of the mineral. The anionic collectors also imparted a negative charge to chromite in the entire pH region. The higher zeta potentials obtained upon adding the anionic collectors is ascribed to the adsorption of anionic surfactant onto the positively charged chromite surface. The positive sites are generated through formation of significant amount of hydroxy complexes of magnesium at pH 11. Complementary infrared data reveal the absence of a shift in the spectra indicating the possibility of physical adsorption in the system.

Jan 1, 1993

The word governing derives from gubernare meaningto pilot a ship. Being inclined to metaphors, one could be forgiven to think that politicians act this verb and captain the Nation's ship into some definite course. In the case of at least the mineral resources industry, it seems that there are not many James Cook followers in our parliaments: Australia's approach to mineral and energy policy is often chaotic - witness the 1935 to 1961 ban on iron ore export-ing which prevented the development of a significant steel industry at time when the World was hungry for this metal, just to mention one amongst many other examples.The follies of Australia's mineral policies are well il-lustrated in the case of uranium mining. Although Australia had the Western World's largest economic reserves of uranium, it is onlythefifth producing nation and its uranium potential is largely unrealised. At the root of this situation are the interventionist attitudes and policies of successive Federal Governments which for more than four decades distorted the Investment decision and, in more recent times. discouraaed investment.

Jan 1, 1990

By Wilson AF

Gold-silver mineralization at Cracow and Ukalunda in Queensland comprise quartz-filled veins, fissures and breccia zones hosted by propylitically altered volcanics and epizonal intrusions which are strongly fractured. The terrestrial volcanic facies, structural setting, type of alteration and complex mineralogy suggest these deposits are of the epithermal type.The 180 depleted character of the wall-rocks is consistent with the involvement of meteoric waters in convective hydrothermal cells associated with the vulcanism. The Cracow quartzes have remarkably low 6180 values from -2.0 to -3.4 per mil typical. of meteoric hydrothermal systems at high latitude, consistent with the inferred position of Australia during the Permian. 6180 values for the Ukalunda quartzes exhibit a wide range from 5.1 to 14.9 per mil which reflect the mixing of magmatic and meteoric waters, and a steep geothermal gradient.Further stable isotope and geochemical studies are in progress to establish the scale and morphology of the zones of anomalous 6180 and mineralogy in the wallrocks which constitute significant exploration targets.

Jan 1, 1984

New Zealand has often been quoted by metallurgists and others as one of the countries in which Tellurium is found, and locally it has been recorded that appreciable quantities of tellurium have been met with in the Thames and surroundingdistricts. However, specimens containing tellurium which have been obtained on this field have not been preserved and their scarcity today points to the fact that tellurium is not here abundant.To ascertain its distribution, analyses and assays have been made by the author on a large number of ores, the results of several of which are given below.The presence of any considerable percentage of tellurium has an important bearing on the metallurgical treatment of ores in which it is found.

Jan 1, 1901

The Bowen Basin coal field is an important energy resource. A relatively small proportion is avail- able by open cut operations. Responsible men throughout the world have warned of the need to increase coal research immediately. Because energy is still available in abundance these warnings have not been heeded in Australia. The characteristics of the Bowen Basin coal make it a fairly difficult underground mining proposition and a significant research effort is required to solve the problems likely to be encountered. Both industry and government have responsibilities in the economic recovery of the maximum proportion of the resource and jointly funded research administered by existing organisations should be inaugurated forthwith.

Jan 1, 1976

By Burgess JM

Research on gas distribution in the iron- making blast furnace has been conducted in three separate areas. Firstly, experimental work has been conducted to determine the important parameters which dictate the pressure losses in homogeneous and heterogen- eous packed beds. Secondly, a theoretical analysis of gas flow through the furnace softening-melting zone has been undertaken to determine the effect of the shape of the zone on the distribution of gas flow towards the furnace walls. Thirdly, a theoretical programme has been undertaken to develop methods for the prediction of furnace soften- ing-melting zone shape from furnace tempera- ture and gas composition measurements.

Jan 1, 1980

Human creativity springs from the natural desire of mankind to know and its capability to learn. Explorers and discoverers possess these features in a high degree. They are driven by an unrelenting curiosity to go beyond the boundaries of the known, to explore into the nature of things, to reveal connections between ideas, facts, conceptions, to view things from new angles, to change perceptions. A well-known fact about the construction industry - and underground construction in particular - is that all projects are unique. The degree of complexity due to the intertwining of the variety of project-related parameters is higher than in many other industries, thus forcing contractors as well as suppliers to be truly adaptable and flexible. The enormous advantages of shotcrete as a construction and rock support process and the improvement of materials, equipment and application know-how have made it a very important and necessary tool for modern underground construction works. The development of modem wet shotcreting in particular has enlarged the field of underground construction work. Projects that were impossible to be realised, have now become practicable. Subsurface structures can be placed where they are needed, without regards as to rock and soil conditions.

Jan 1, 1995

By Svenson D

Most exploratory drilling in the N.S.W. coal fields has been conducted using convent- ional diamond drill rigs of modern design, us- ually truck or trailer mounted. Conventional diamond drill rigs have also been used exten- sively by the Queensland Department of Mines for coal exploration. However almost all of the exploratory drilling of surface mine coal prospects throughout Queensland has been conducted using rotary rigs typified by the Mayhew 1000 truck mounted unit. The rotary rig has proved capable of both rapid non-core drilling and core drilling with high core recoveries when modern core barrels have been used by experienced drillers. For deep or continuous core drilling, wire-line equipment is now in general use. Both wire-line and conventional coring is effected using stationary split inner tube barrels, for minimum core disturbance, maximum core recovery, ease and accuracy of logging and sub-sectional sampling. Diamond core bits are generally required in N.S.W., with water circu- lation. In Queensland, the generally softer coal measures strata can be successfully cored using tungsten carbide bits and air circulation is the preferred method where possible.

Jan 1, 1977

By West R

Since its introduction in 1989, the Australasian Joint Ore Reserves Code (the JORC Code or the Code) has been one of the success stories of the informational interface between the mining industry and investors. This is due variously to the user-friendly nature of the Code itself, to its practical approach to this complex subject, and to the way in which its requirements have been implemented in practice. Recognition of its utility and effectiveness has influenced a significant number of mining countries to re-assess their reporting standards with the positive outcome being that for the first time, a set of standard international definitions for reporting of mineral resources and reserves is a realistic possibility.

Jan 1, 1996

By Dunlop GA

Pilot Plant confirmatory testing of the treatment route developed in the Metallurgical Laboratory is an essential factor in the development of complex ore bodies. Objectives should be well defined to permit the efficient planning and cost effective operation of the pilot plant project. The primary objective for the pilot plant should be to confirm the viability of the developed flowsheet on a continuous basis, examining only major variables such as ore types, quantum changes in grind, comparison between bulk and sequential flotation circuits, use of flotation columns, evaluation of autogenous grinding and production of samples of concentrates for market evaluation. Secondary objectives may include the collection of engineering design data and the production of a comprehensive report to Bankable Document standards to provide technical support for capital financing. The complexity of the ore body and the scale of the final operating project together with the pilot plant objectives will determine the extent of the pilot plant operations. The level of expenditure associated with a pilot plant can vary, in total cost and as a percentage of the total development capital investment required to take the prospect from exploration to a producing mine. Factors contributing to expenditure are discussed. Associated with cost considerations is the level of confidence mining company investors can have that their capital investment will return dividends.

Jan 1, 1990

By Braithwaite J. C

A brief summary is given of the applications of geochemistry on two areas in North West Nelson. It has been found to be an effective method for reconnaissance prospecting. Its particular advantage lies in areas which due to thick bush cover or ru

Jan 1, 1980

THE following notes simply sum up the writer's experience, which extended over a very busy period of some three years, dealing with wolfram ores and concentrates. The three methods for the estimation of tungsten that are discussed below are well known, but these results of their trials and comparison under technical conditions may be interesting. Method I. The routine procedure for the assay of rich wolfram ores or concentrates was as follows: Take 1 gram of finely-ground sample; digest with HCl and HNOs for about 2 hours, evaporating down to near dryness. To the remaining 5 cc., say, of liquid, add water, warm or boil for 1 to 1.5 hour, filter through a small filter paper, and wash the beaker and the insoluble matter with hot dilute HCl. It is best to keep the bulk of the insoluble matter (WOs, Si02, etc.) in the beaker at this stage. Then plaee a weighed porcelain dish under the filter funnel and wash the beaker and the filter paper with successive small quantities of strong NHOH, finally bringing all the insoluble matter on to the filter paper, and collecting the ammoniacal filtrates in the porcelain dish (S). Then place the filter paper with the insoluble matter in a porcelain crucible, dry and burn off the paper, cool, and brush the contents of the crucible on to an agate mortar, grind it to flour, and brush this back to the original beaker without loss. In the absence of draughts this can be done safely. Re-treat this residue with' acid and ammonia as above, running the second ammoniacal filtrate into the previous porcelain dish, which in the meantime has been heating on a water-bath.Finally evaporate to dryness on the water-bath the combined ammoniaeal filtrate, and then heat gradually to a red heat over a Bunsen burner, cool, and weigh. Then the contents of the porcelain dish give the WOs (tungstie aeid) direcvly (5).The final filter paper and insoluble matter may be ignited in a porcelain crucible, thus giving the "insoluble matter." If the ore...

Jan 1, 1922

It is well known that in most areas of Central Europe it is not difficult to find water - usually at shallow depths - and to recover and use this water. What is much more difficult, however, is to find water sources that offer both sufficient in quantity and qual- ity. Far too often, there are sources that offer abundant quantities but of poor quality or vice versa, i.e. high quality water but insufficient volumes. In the former case where water quality is not adequate - which is more often than not due to anthropogenic factors and only very rarely a result of geogenic effects - the application of treatment techniques can help to turn such water into potable water that is suitable for human con sumption.

Jan 1, 1988

(Quality can be defined as that which is acceptable to the market and can be supplied with a predictable degree of uniformity and dependability at a low cost. The market for any mining product is downstream processing, whether it be an alumina refinery, a gold processing plant or a flotation plant. The cost of that downstream process is partly dependent on uniformity of its feed material both in physical and chemical terms. With more operations adopting procedures which require quality assurances in line with International Standards, from their raw material suppliers, miners must look to their grade control processes to provide uniformity and predicability.This is not a new concept. The mining industry has constantly been working with ahighly variable raw material supplied by Mother Nature, from whom we cannot demand quality assurances. Through the processes of exploration, resource and reserve definition, long and short term mine planning and day to day grade control an end product has been supplied which consistently meets our customers requirements, in an economic fashion. When any of these processes fail, then penalties are incurred which can range from increased mineral processing costs to loss of markets and in the ultimate case, failure of a mining operation.

Jan 1, 1992

By M F. Lee

In order to make good decisions, as to whether large diameter raise bored shafts can be constructed in blocky rock at a particular location, mine planners, management, geotechnical engineers and contractors must understand and consider a range of geotechnical issues. Firstly, mine management must ensure that adequate time and resources are available to find appropriate shaft sites. Deep weathering, adverse structures, groundwater, etc might mean that the most desirable location, with respect to other mine development, might not be suitable. Special site investigation drilling, etc may be necessary. Even then, alternative construction options might be necessary, other than just reaming through to the surface. A site investigation borehole should then be drilled to investigate specific and general ground conditions along the raise alignment. Often, only small sections of weak blocky rock dictate raise stability. While the empirical McCracken and Stacey method is typically used in Australia to assess raise stability and assess geotechnical risk, until recently it had no published performance data.An Australian database of raise performance now exists and is presented below, courtesy of an industry survey by the Eastern Australian Ground Control Group. Raise diameter and ground conditions (in terms of a lower bound Qr value) is presented for 50 cases versus raise performance.

Jan 1, 2008

Since the announcement of early experimental work on rotating magnetic field (RMF) separation at the Sixth Mill OperatorsÆ Conference in 1997, the concept of RMF separation has been developed and tested further, and a range of separator designs is now being developed for the mineral processing industry. Shortened, but full diameter, prototypes of these designs are now available for test separations. The main advantage of RMF low and medium intensity attraction separation is the significant reduction in particle entrapment. This reduction is so significant that RMF separators are capable of operating very close to their theoretical limit for separator precision. This makes small laboratory RMF attraction separators ideal for low to medium intensity magnetic sample analysis, and larger separators ideal for applications requiring sharp magnetic susceptibility splits. Feedrates and separation rates are comparable to those of conventional attraction separators. Although RMF attraction separators are now well advanced in development, RMF rotation separation is still in the early experimental stage. The exception to this is the dry particle rotation eddy current separator that offers eddy current separation of small non-ferrous metallic particles from about 2 mm down to about 100 microns. Wet small particle eddy current separation is also possible, but has not yet been developed to a practical stage.

Jan 1, 2000

By Hatherly P, Dunn P

There are- several in-seam coal research projects currently under investigation by the Cooperative Research Centre for Mining Technology and Equipment (CMTE). The overall aim of the projects is to produce new technologies to enhance safety and the efficiency of in-seam gas drainage drilling. Results from high pressure waterjet rotary drilling trials indicate that by applying high pressure water to a rotary drill bit, the hole can be drilled to follow the planned trajectory very closely. Steerable drill bits for drilling long holes (>1 km) have been produced and trialed. A flexible high speed drilling system provides a capacity for rapid in-seam drilling, particularly suited to cross panel drainage. Geophysical tools are being developed to provide a geological steering capability and a better understanding of potential gas outbursts zones.

Jan 1, 1998

By K Luthbom, A Lagerkvist

According to the Swedish Environmental Protection Agency, the number of potentially contaminated sites in Sweden is approximately 40 000. The funding for remediation from the Swedish Government alone amounts to $A 60 - 80 M (300 - 400 MSEK) annually for the period 2003 - 2006. Uncertainties will arise when obtaining samples in field, preparing them in laboratories and analysing them. Different procedures give rise to varying errors. Using data for decision-making that does not truly represent the site could be fatal. Misclassification of soil could lead to unnecessary costs or to risks to human health and the environment. The total uncertainty of an environmental sample can be split into analytical uncertainty and sampling uncertainty. The analytical uncertainty is usually known and reported from routine analysis. The size of the sampling uncertainty is less well known. Hence, the question is how big are the sampling uncertainties for contaminated soil and how big is the analytical error compared to the total sampling error? A scrap yard and two landfills within a workshop area were investigated. An excavator dug trial pits and samples were taken with a trowel from the walls of the trial pits. Samples were put into plastic bags and taken off site for preparation and analysis using XRF. Sample preparation included drying and sieving. The samples were homogenised by kneading the sample bags prior to analysis. The sampling and sample handling were performed in an intuitively way without knowledge of sampling theory. However, Pierre GyÆs sampling theory was used for subsequent evaluation of the data from the site investigation. The theory defines seven sampling errors, which can be applied to sampling of soil. Some errors have a variance that can be calculated or at least estimated, while other errors can give some idea whether the bias is positive or negative. The total sampling error varied over three orders of magnitudes from sample to sample. The single largest contributor to the large variation in error was the contaminant level. When comparing the analytical error and the total sampling error the ratio varies more than three orders of magnitude.

Jan 1, 2005

High precision GPS systems for mining are accurate to within a few centimetres. Typical systems consist of one or more GPS antenna, GPS boards, sensors to detect the position of the blade or bucket of the machine radios to pick up correction signals, a computer to control the system and a display screen to give instructions and information to the operator. GPS systems offer two benefits û they give information to the operator to get his job done faster and more accurately and they can send information to management about how the job was done. On dozers, GPS systems allow the operator to accurately complete earthmoving jobs with no survey pegs. On hydraulic excavators the systems can be used to accurately locate the position of the bucket teeth for selective mining. On blasthole drills the systems can guide the operator to each hole and record accurate as-drilled plans. By reporting the position of the blade or bucket in three dimensions it is possible to continuously upgrade a mapfile of the excavation. From this file it is then possible to report productivity numbers in real time. High precision GPS works best with a minimum of five satellites visible. This may be difficult in a pit. Systems which also access the Russian GLONASSS satellites offer significantly better uptime. GPS systems will become indispensable for efficient mining operations in the future.

Jan 1, 2003