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By P Collier

From 1972 until 1989 when operations were suspended Bougainville Copper Limited (BCL, owned 53.58 per cent by Rio Tinto Limited) operated a large open pit mine and processing facility at Panguna on Bougainville Island, Papua New Guinea producing copper concentrate containing significant quantities of gold and silver.BCL has a stated vision of recommencing operations at Panguna. In 2008, Rio Tinto, on behalf of BCL, conducted a multi-disciplinary study to assess the technical and financial viability of redeveloping the Panguna operation. One of the key outputs of the study was a Joint Ore Reserves Committee (JORC) Code compliant mineral resource statement based on the existing block model and fundamental data, archived since mine closure. Historical data (including the resource block model and drill hole data) was recovered from computer archives by a former Panguna mine employee familiar with the various obsolete data formats, thus maintaining an unbroken chain of custody of the data by Rio Tinto since operations were suspended. No additional data were collected as part of this study.The extensive data and documentation archive facilitated a sufficiently detailed evaluation of the fundamental data and model to support an updated resource statement. Table 1 of the JORC Code was used to guide the model validation process.Reconciliation of blasthole and metallurgical plant data with the reserve model, indicated that the copper and gold drill hole composite database was significantly biased towards underestimation in several key domains due to a combination of the following: mineralisation loss during core loss, core loss (minor), vertical drill holes failing to intersect sufficient subvertical mineralised fractures and veins, drill hole spacing too wide, and variable diamond drill hole core size. The resource model evaluation was based on three material types (all previously mined at Panguna), that were defined based on cut-off grade and rock type parameters: direct feed ore – material for delivery directly to the plant, preconcentration and screening ore – subeconomic material beneficiated to produce fines of economic grade, and waste. Three pit shells and designs were generated based on three separate sets of economic parameters. These economic parameters were also used to assign material types to the block model. The three resulting models were then evaluated against the corresponding pit shells.Classification of the resource was approached conservatively due to the inherent bias in the drill hole data. Consequently only Indicated and Inferred resources were tabulated.The study highlighted the importance of maintaining detailed documentation pertaining to resource estimates and operational history, particularly reconciliation, and the value that can be added by a simple, low-cost data compilation exercise.

Aug 22, 2011

Uranium ore at Sleisbeck, N.T., occurs as lenticular bodies associated with zones of bleached carbonized schists lying between walls of closely folded quartzite. The ore consists mainly of uranium micas with Borne pitchblende.INTRODUCTIONThe Sleisbeck uranium prospect is about 70 miles E. of Pine Creek, and 160 miles S.E. of Darwin (Fig. 1). The prospect consists of a well-defined, E.-W. trending line of hills, about I! miles long. The line is composed of 3 major hills called the Eastern, Central and Western hills, with minor interconnecting hills and outcrops (Fig. 2).

Jan 1, 1955

Six years ago it was my responsibility to give the presidential address, and now that privilege has come my way again. On that occasion we were gathered atWhyalla and I took the opportunity of putting before members some observations on the problems we then faced in Australia, and some gains we had been able to chalk up during those early postwar years. You may recall that we were then just beginning to emerge from the difficulties of postwar reconstructions - of fuel and power shortages, and a grossly inadequate manpower for the tasks facing us. The expansion of manufacturing industry in Australia greatly stimulated by wartime activities, and by the postwar developments of many institutions - ran ahead of the supporting services and of the supply of labour to do thejobs. For many industries this unfortunate state of affairs had meant operating at rates well below their installed capacities and therefore levels of output insufficient for Australia's rapidly growing needs. When I last spoke to you these problems were still with us, though their intensity was beginning to lessen as a result of vigorous efforts by industry and governments to reduce them. But I must confess that my thoughts on that occasion were full of those problems and of the effect they were having on the iron and steel industry of this country-of the coal shortage, the labour shortage, and the many other difficulties we were then faced with - and all at a time when the stepping up of our postwar expansion programme was of vital concern to all of us.What a different picture it is six years later! How greatly has the scene changed for the better. In 1951 Australia's postwar immigration programme was only in...

Jan 1, 1957

By Fogarty J. G H

Ausmelt Technology has a unique capability of removing the impurities, phosphorus and sulphur, from the feed materials to the process. Sulphur is removed to the gas phase almost completely because of the interactions of ore and coal in the reaction region at the top surface of the slag bath. Phosphorus is removed to the slag phase, with both basic and higher, controlled iron oxide levels in slag being achieved in the process. The significance of these features of the process relate to the production of pig iron with very low levels of these impurities for the further processing to steel, and to the treatment of high phosphorus and high sulphur raw materials. The marketability of pig iron and the raw materials are discussed in relation to this feature of Auslron.

Jan 1, 1999

A numerical method for discriminating between replacement and sedimentary processes is applied to a folded stratiform sulphide occurrence. It is shown that numerical treatment of chemical analyses from a single diamond drill hole allowed a rapid assignment of the ore to the syngenetic sedimentary class and thereby enabled a revision of the evaluation program concerned with consequent reduction in costs.

Jan 1, 1973

Heap leaching of copper sulphide and oxide ores' has been conducted at Rum Jungle since the end of 1965.A review of operations was made and this led to an examination of some theoretical aspects of copper sulphide heap leaching. Ox,ygen diffusion was indicated to be the factor controlling copper leaching rate at Rum Jungle and in other similar operations. Suggestions are made for measuring the heap leaching rate. Prediction of full scale operational results from pilot scale testwork are discussed.

Jan 1, 1969

By M G. Shaw, M A. Rhamdhani, S P. Singh, A R. Duffy, B Eisenbart, A K. Shukla, G A. Brooks

The field of astrometallurgy is a growing area of study. Metal production on the Moon is likely to begin in less than a decade as major space agencies such as NASA (National Aeronautics and Space Administration) and CNSA (China National Space Administration) are preparing to construct permanent lunar bases. The utilisation of regolith to generate oxygen and metals is expected to be important in the development of a sustainable lunar habitat. This paper provides an overview of potential metallurgical processing methods for lunar conditions, emphasising the impact of lunar factors on slag chemistry. The interaction between regolith and the extracted metals, as well as their impact on slag composition and refractory performance, are critical considerations in metal production on the lunar surface. The initial research on lunar metallurgical technologies is focused on oxygen extraction and Fe-Si alloys are reported as the by-products of these processes. This paper delves into the fundamental thermodynamics associated with the carbothermic reduction of lunar regolith. Thermodynamic analysis using the FactSage™ ver 8.2 software package indicates that the Fe-Si alloy can be produced as a metallic product from the lunar regolith at temperatures ranging from 1400°C to 1600°C under terrestrial conditions. However, under ultra-high vacuum conditions (3 × 10-15 bar) on the Moon, the required operating temperature for producing ferrosilicon would be significantly reduced. Thermodynamic modelling results indicate that under lunar vacuum conditions, Fe-Si alloys only exist as solid phases at lower temperatures below 650°C. At higher temperatures, both Fe and Si are expected to be present in the gas phase. In this work, the carbothermic reduction of the Lunar Mare Simulant (LMS-1) is conducted under terrestrial conditions. The findings indicate that the process can readily yield Fe-Si alloys with 7–10 wt per cent Si at 1600°C. Additionally, energy dispersive spectroscopy (EDS) analysis of the resulting Fe-Si alloy indicates the presence of phosphorus up to 1 wt per cent.

Aug 21, 2024

By Narasimhan K. S, Sastri S. R

A typical high silica low grade magnesite from the Salem area of Southern India, was used in studies to develop a suitable flotation system involving commercially inexpensive sodium oleate as the collector together with other reagents which can give a product of the required grade with an acceptable recovery. It was found that the presence of metallic ions such as Cu+, Fe+++ or Ca++ introduced by the addition of their salts, or by their formation with the addition of hydrochloric acid to react with magnesium and calcium carbonate in the me, can act as effective depressants for silica. The addition of 'hydrochloric acid' was found to give best results.

Jan 1, 1980

The Manto Verde mine is found in the coastal ranges of the Atacama desert, 1000 km north of Santiago, Chile . The deposit is a fault-breccia specularite-oxide copper mineralisation hosted by the Jurassic andesites of La Negra Formation. It is located in a tensional fault that joins twoparallel arms of the Atacama Fault. The mine is in feasibility study: reserves are of the order of 60 Mt at 0.9 wt per cent soluble copper; mining will be undertaken at a rate of 11 000 tpd utilising an open pit and the ore will be heap-leached with acidified sea water, with copper recovery and by SX/EW.

Jan 1, 1992

n the early days of the Hauraki goldfield (1866 to 1889) almost the only system of ore treatment was wet crushing followed by copper plate amalgamation. A further saving of bullion was in most cases obtained from the tailings by means of pans or berdans. Though this system was not always as efficient as might have been desired it answered fairly well for the bulk of the gold-bearing quartz of the Thames and Coromandel districts, where the gold occurs chiefly in the form of visible particles, and there is not a great deal of silver. It failed, however, with most of the ore found in the Upper Thames or Ohinemuri district, especially in the Karangahake and Waihi portions of the field. In those days the cyanide process was not, and the usual prescription of the mining " expert" was smelting. At Karangahake, many attempts were made to discover a payable method of treatment for the so-called" refractory" ore, but on thewhole with very 'little success, and the district struggled along for a number of years without adding very materially to the production of gold in New Zealand. At Waihi, the Martha Co.'s stamp battery treated by wet crushing and copper plate amalgamation some 18,000 tons from the Martha Reef, worth probablyat least £4 per ton, but the average return was considerably less than £1 per ton, a sum which barely paid working, expenses, and consequently the shareholders were glad...

Jan 1, 1903

The passage of chloroform vapour in a carrier of oxygen through two nickel sulphide ores heated to 380°C converted the nickel to the water soluble chloride form. In one ore the nickel (2·75 per cent) was presentas violarite ((Ni, Fe)3S4) whereas in the second it was present as pentlandite, ((Fe, Ni)9S8) (4·9 per cent Ni).A similar technique was utilized to convert nickel in nickeliferous laterites (1·6 per cent Ni) into a soluble chloride using town gas instead of oxygen as a carrier.With both techniques greater than 90 per cent extraction was achieved.

Jan 1, 1972

By L Matthews, D O’Dea, P C Hayes, J Manuel, B Monaghan, T Honeyands, D Pinson, J Leedham

Many different approaches have been used in the past to characterise iron ore sinter mineralogy to predict sinter quality and elucidate the impacts of iron ore characteristics and process variables on the mechanisms of sintering. Characterisation techniques include optical image analysis and point counting, X-ray diffraction and scanning electron microscopy. Each technique has its advantages and disadvantages depending on the objectives of the measurement. It is generally acknowledged that silicoferrite of calcium and aluminium (SFCA) is very important to the quality of the sinter produced; however, strict definitions of the phases and textures of SFCA are not generally agreed. This paper summarises the state-of-the-art in sinter characterisation applied in Australia by both academics and industrial researchers. The results from various techniques are compared and the relationships between the measurement results are discussed.CITATION:Honeyands, T, Manuel, J, Matthews, L, O’Dea, D, Pinson, D, Leedham, J, Monaghan, B, Li, H, Chen, J, Hayes, P C, Donskoi, E and Pownceby, M I, 2017. Characterising the mineralogy of iron ore sinters – state-of-the-art in Australia, in Proceedings Iron Ore 2017, pp 49–60 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

Ensuring the success of a major resource development project, whether in the Gippsland Basin or elsewhere, is typically both a complex and costly process. It is therefore imperative from the point of view of the proponents of such a project - and in particular the financiers - that everything possible be done to minimise administrative confusion and delay in the establishment phase of the project, and to put systems in place which enable the project to run smoothly and efficiently in the later stages of its development and operation. An essential element in this process is ensuring that the project management is able to come to terms with and deal effectively with the relevant planning and environmental laws.

Jan 1, 1992

In late 1989, first-pass reconnaissance exploration delineated a 4km x 6km geochem- ically anomalous area centred 10km WNW of Kainantu in the Eastern Highlands Province at 6¦13'S and 145047'E. The area, named the Basangka prospect, lies between 2 200 and 2 400m asl. Interest in the area was prompted by a 14ppm Au assay of a silica-pyrite breccia float sample taken near Henkai village. The prospect was defined after several acid-leached silica- pyrite breccia and comb textured quartz float samples returned assays above lppm Au and relatively high Ag. Very encouraging and anomalous Au values were obtained from panned concentrates, despite the absence of visible Au colours. Several pan concentrates returned greater than 1mg Au and it is believed that the Au occurs as inclusions within iron oxides which were originally pyrite. In this early stage of prospect exploration, any Au value above 0.lppm in- 150# fraction stream sediments is treated as anomalous. Rock chips, panned concentrates and -150# fraction geochemistry all vividly define the areas of interest at Basangka.

Jan 1, 1991

Ore samples generally require preparation before analysis. Serious problems can occur with contamination degradation and particle size effects. Both grinding element contammation and sample cross contamination havebeen bound to be related to sample hardness and operator technique. For best results with minerals relevant to the steel industry, the use of Siebtechnik-type mills required a combination of careful planning, short grinding periods and intermediate sieving of the sample. The results may be extended to most mineral, rock, and refractory sample preparabons.

Jan 1, 1978

In the last 40 years, New Zealand has developed a number of liquid- dominated geothermal steam fields, for electricity generation and indus- trial process steam. New technologies were developed, and in this work, New Zealand led the world. The policy of full publication of the results, in a wide range of sciences, provided a reservoir of detailed data defin- ing the geology, size and shape, and the chemical and physical regime, of many geothermal fields and their constituent parts. The discovery of precious and base metal deposits /precipitates in geothermal drill cores and steamfield equipment, suggested a clear link- age with epithermal mineral fields in general, and with that of the Coromandel (Hauraki) Region in particular. Further work on geothermal/ epithermal relationships have implied that the techniques, developed to obtain an understanding of geothermal fields, could be applied also to epithermal mineral exploration. This work is developing fast, and is now proceeding in many coun- tries. Future work may show that the presumed relationship between geothermal and epithermal deposits may be applicable in the wider con- texts of all hydrothermal deposits, and possibly in many other minera- lised areas with volcanic "country rocks".

Jan 1, 1988

By Pullen G, Rose M

Continuing Professional Development (CPD) is not just a catch-cry. It is an essential component of every-day life in many professions, including accountancy, law and public administration. Without realising it, many other professions are undertaking CPD activities in an un-structured way, including mining, metallurgy and geology. Examples include Annual and technical conferences of The Institute, Branch-level technical meetings and in-company training and development programmes and technical exchanges. Whilst approaches to date have undoubtedly helped keep the Australian mining industry at the forefront of mining technology, one cannot presume that technological development will stand still. To meet this challenge, human resource development must keep pace, not only to optimize utilization of technological developments, but more importantly to develop firm bases from which new products, processes and technologies can be developed within Australia.

Jan 1, 1989

An account is given of experimental apparatus for generating a short duration high velocity water jet and the effect of its impingement on various rock samples under air or water cover. The penetration was found to be highly dependent upon the rock structure; in general material with closely interlocking grains was resistant.The damage sustained by a stationary sample held close to the jet did not vary greatly whether the sample was in air or confined under a water layer; but when the sample was translated under the jet there was a marked increase in the damage sustained.Some consideration was given to the possible practical application of a water jet for deep hole drilling and an estimate made of the power requirements and transmission losses for such a system.

Jan 1, 1969

By Woodcock J. T, Jackson N

Wattle Gully Gold Mines N.L. of Chewton, Victoria, has decided to replace its present battery plant by a new mill to treat a free milling gold ore, after fine grinding, by concentrating coarse gold in a jig concentrate for amalgamation, and fine free gold and auriferous sulphides in a flotation concentrate for cyanidation. This paper outlines the economic justification and advantages of this step. In a review of the present position at the mine, a history of the company is followed by a description of the ore and its occurrence.Present treatment practice in two separate battery plants is described. Treatment tailings assay 1 dwt/ton gold and a substantial part of this gold is finer than 200 mesh.Experimental work showing how recovery may be improved is discussed and alternative methods of concentrating coarse gold mentioned. It is decided that the most suitable method for recovering gold from the ore is by jig concentration plus flotation.The merits of various flowsheets incorporating these techniques in the existing plant and in a new plant are assessed. It is concluded that there is no advantage in extending or converting the existing two battery plants, and it would be more economical and satisfactory to build a new plant.An economic study shows that for a capital expenditure of £120,000 a new plant could be erected to treat 70,000 tons p.a., working a 5-day week, and return an additional 14.2/- per ton, or £50,000 p.a., in revenue over the existing plant. It is estimated the plant cost can therefore be recouped out of savings inside three years. Probable ore reserves are sufficient to cover this period and additional ore will certainly be developed.INTRODUCTIQNSince 1934, Wattle Gully Gold Mines N.L. has been mining a lode gold ore at Chewton, near Castleniaine, and treating it by stamp milling and plate amalgamation, plus table concentration of auriferous sulphides. In 1954, following two years of unprofitable operation, a rehabilitation programme of all sections of the mine and plant was commenced. In the treatment section, two, major prospects for improvement...

Jan 1, 1959

The labour question is one that has caused mine managers much thought and anxiety and is likely to continue to do so as long as human beings exist. The difficulty is to devise some arrangement whereby the interests of miner and mine ownerare identical. Mines cannot be worked without capital, and capital is no good without labour, yet, though both have the mine in common, their interests are not exactly the same. Some men are happy so long as they can scrape through by exerting themselves as little as possible, but capitalists do not work mines for charity, they want some return for their money.Where a large number of men are employed there are bound to be examples of all sorts, good and bad, and it is because one cannot depend on all, that different methods of employment have to be adopted. Which method is selected depends to a great extent on the labour market, local conditions, nature of the ore and the way in which it occurs.A big step towards success is obtained by securing the services of good bosses, not only those who know how work should be done, but men who have a knowledge of human nature. It is a big mistake to be too lenient with a man, also to be unnecessarily harsh. A good boss will always be sought out by good men who have worked under him before, or who have heard of him from others. By a good boss we do not mean one who employs two men where one would do, or who lets the men loaf...

Jan 1, 1901