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Recent and on-going studies on the leaching of gold, the properties and activity of carbon, developments in the elution of gold from carbon, and methods of recovering gold from solution are reviewed. Emphasis is placed on Australian contributions, and their impact on gold metallurgy. Consideration is given to the future development of selective solvent extractants, ion exchange resins or alternative reagents for cyanide.

Jan 1, 1987

By B S. Utting, W J. Cowie

The alluvial gold industry of New Zealand is based on the placer deposits in Otago and on the West Coast. Production from these since discovery in the 1850s has been an estimated 480 t (15 Moz) of gold. Annual output has expanded continuously since 1980 and is expected to be over 2 t of gold for 1989. Following a historical review, the characteristics of typical operations, which use hydraulic excavators and mobile trommel units are discussed. Descriptions are then given of alluvial activities in Otago and on the West Coast.

Jan 1, 1990

Australia's iron ore industry is entering a challenging period with the development of new orebodies, the introduction of new products and the push for further downstream processing. In addition, the recent price reductions for iron ore exports have intensified the focus on reducing capital and operating costs. To assist in these areas, CSIRO is expanding its research capabilities, including the incorporation into CSIRO of the Mineral Processing Laboratories in Perth, which were previously managed by the WA Department of Minerals and Energy. In addition, a large part of the $24.4 million expansion of CSIRO's Pinjarra Hills laboratories in Brisbane will be devoted to enhancing iron ore processing research, providing purpose built laboratories and large process bays.

Jan 1, 1999

The process of electrostatic separation was developed in the late 19th century, but did not make much headway for about 25 years. High dc voltages, of the order of 20 kilovolts, are involved, and the only means of obtaining such voltages at that time were by the use of frictional machines, such as the Wimshurst. These were not reliable, for two reasons:-a. If a spark discharge occurred it took an appreciable time before a steady voltage was again attained.b. In damp weather the machines were almost useless.In the first 20 years of the 20th century the advent of mechanical and vacuum-tube rectifiers led to promising developments of 'the process. In the early 1920's flotation became widely used commercially, and proved to be more reliable, and capable of wider application, than electrostatic separation. During the last 15 years or so, with a better knowledge of the fundamentals forming the basis of the process, electrostatic separation is beginning to compete with flotation, especially in the treatment of smallsizedgranular material, such as beach sands. Electrostatic separation can be, and is, widely used in many cases where flotation is impossible, such as in the cleaning of food products which must be kept dry.

Jan 1, 1950

Operational effectiveness is fundamental to any operation, becoming highly topical in those experiencing less than optimal output from their fleets. It is all encompassing aiming to identify those factors that could be improved within production and suggesting solutions in order to optimise the existing fleet and obtain the greatest capital return on expenditure.Argyle Diamond Mine (ADM) is a large open cut diamond mine located in the East Kimberley region of Western Australia, approximately 180 km south of Kununurra. It is owned and operated by Rio Tinto on a two week on/two week off roster fly-in/fly-out from Perth or drive in/drive out from Kununurra. Through benchmarking the operation between January and June 2002, a study was undertaken allowing identification of areas falling below target. Following this, analysis of annualised hours and production downtimes were undertaken to quantify the potential gains of improvements in these areas. Strategies were then identified as stated in the 2002 mine plan, in operational effectiveness meetings, and by staff members. This project aimed to maximise direct working hours through determination of the main issues hindering performance. External and internal factors were considered and a continuous improvement program (CIP) was developed. The CIP aimed at internal site-based improvement teams to identify and implement solutions for improvement on a day-to-day basis.

Jan 1, 2003

By Rao P. K, Sahoo P. K

The main constituents of ferromanganese slags are silicates of Mn, Ca and AI. Factors affecting the recovery of manganese from a low manganese content ferromanganese slag (about 16 per cent MnO) during acid leaching were studied. These included time, temperature, agitation, sulphuric acid addition, solid:liquid ratio and particle size. Agitation rates greater than 300 rev/min. leaching periods greater than 30 min and temperatures above ambient were found to have no effect on Mn recovery. Dissolution of Mn was found to be highly dependent on the amount of acid added.About 90 per cent of the Mn was recovered when 5·5 times the stoichiometric amount of acid was used. About 28 per cent of the Mn was recovered when the stoichiometric quantity of acid (with respect to Mn alone) was used. However, the recovery increased to about 75 per cent when the total stoichiometric requirement of acid with respect to Ca, Al, Mg and Fe as well as Mn was used for leaching. The extent of Mn dissolution also depended on the particle size of the slag. The percentage of Mn recovery (using 5·5 times the stoichiometric amount of acid) increased from about 60 per cent to about 92 per cent when particle size decreased from -36 +52 to -150 +200 mesh (B.S.S.). When the results of this study were compared with those in a previous study involv,ing the leaching of a high manganese content slag (containing about 40 per cent MnO) results were similar except that there was a gr-eater consumption of acid in the present case (i.e. low manganese content slag).

Jan 1, 1979

By Elford H. S

Mr. H. W. GEPP said he desired to bring particular attention to this paper. The underlying intention of the Development and Migration Commission when the paper was prepared was to place at the disposal of Australian miners and metallurgists the story of the development of tin metallurgy as it had been advanced in other countries, particularly Great Britain. They had very considerable resources of low-grade tin-bearing metals in the eastern coast of Australia particularly, and they need not anticipate that tin was going to remain at the extremely low price at which they saw it to-day. The Commission felt that it was most desirable to place 'on record, and make easily available, the story of the treatment of comparatively low-grade tin ores in other parts of the world.Arrangements were made that the technical staff at Australia House, in conjunction with Mr. H. S. Elford; should collect this information so that in due course, when Australia awoke to an interest in low-grade deposits, of which there were many throughout Australia, this story would then not,have to be gathered from other areas and other places of the world. The -paper was a contribution which would turn out to be of very great value. He suggested to the younger members that this thorough contribution could be made the subject of study so that they would be ready to assist in the developments which must come. Mr. WM. APLIN said there was one point in connection with the paper upon which he would like to speak. While at Mount Morgan he had occasion to test some highly pyritic tin ore by flotation, with a view to separating the cassiterite from the pyritic mineral.Instead of accomplishing that, it was discovered that it would be possible to eliminate as much as 50% of the total weight of ore in the form of a pyritic flotation concentrate, which would contain...

Jan 1, 1930

ALTHOUGH it has been a matter of about one hundred years since the idea of the internal-combustion engine entered the mind of the inventor, the practical application of its use was not attained till 1860, when Lenoir produced an engine similar to the ordinary highpressure steam engine, with the valves arranged to admit the explosive mixture and the discharge of the exhaust gases. In this case no attempt was made to compress the gas before ignition, as it was then considered that the explosion under these conditions had a detrimental effect, inasmuch as it would act as a sudden blow to the working parts. Indeed, he went so far as to inject steam and water sprays to reduce the explosion.Under these conditions the consumption of gas was exceedingly high-about 106 cub. ft. of coal gas per b.h.p. per hour but the mechanical effect showed that the engine ran in every respect as smoothly and quietly as in best steam-engine practice.The extravagant consumption of this engine was clearly pointed out at the time by Gustav Schmidt in a paper before the German Society of Engineers, wherein he states :-" The results would be far more favourable if compression pumps, worked from the engine, compressed the cold air and cold gas to three atmospheres before entrance into the cylinder. By this means a greater expansion and transformation of heat is possible."

Jan 1, 1912

A review of historic mining information and geological literature pertaining to the Alpine Mine, Lyell Goldfield has been completed. As a result of this work the Alpine reef is inferred to be associated with an upright anticline with a sub-horizontal axis. Structural profiles prepared from limited underground data indicate that the reef is subparallel to the eastern limb of the anticline and cuts across the western limb. Reassessment of structural mapping completed by the New Zealand Geological Survey indicates that Greenland Group metasediments within the Lyell Goldfield are folded into a series of opposed assymetic folds with sub-horizontal axes. It is suggested that the anticline which harbours the Alpine Reef is located on the axis of a synclinorium. Along the western limb of the synclinorium the subsidiary folds have steep west dipping limbs and shallow east dipping limbs (western sense of assymmetry) whereas shallow west dips and steep east dips are typical of the eastern limb. The notion of quartz mineralisation occupying the axis of a synclinorium is contrary to the situation in the Reefton Goldfield where quartz mineralisation is affiliated with folds associated with an anticlinorium. Historic mine data reveals that below No.4 Level the quartz-gold mineralisation, in the Alpine Mine, occupied a steeply dipping ore channel. The strike of the channel was to the northwest and within this structure the are shoots plunged to the north at approximately 40¦. Archival mine plans show that two quartz bodies, the North and South Blocks, were present at No. 4 Level. Although the North Block was followed down to No 14 Level (530 m vertically below the surface outcrop) the South Block was only mined as far as No 7 Level. Sampling on No 7 Level together with the results of trial mining suggest that the grade of quartz underfoot in South Block is low. Information from the Mines Statements and mapping undertaken by the Gold Prospecting Scheme reveals that faulting had a profound influence on the intregity and extent of the Alpine Reef. The reef occupies a Inajor shear zone but little is known about it. It is also apparent that below No 7 Level the reef was progressively shattered by faulting and this may be the chief reason for the decrease in grade in the lower levels of the mine. No substantive facts are available about wall rock alteration effects adjacent to the Alpine Reef Still this is not surprising considering that comments on the mineralised pug envelope and breccias adjacent to the mined quartz shoots at the Globe - Progress Prospect were omitted from contemporary publications. In spite of this the existance of sulphide bearing reef casing lithologies cannot be completely dismissed since 9.15 m of 'reef track' has been reported in Reids No 2 Level.

Jan 1, 1996

In preparing a paper such as this it was thought that the Newstan Colliery Company Ltd., being comparatively new, would need some introduction to mining people in general.The Newstan Company was formed by the Joint Coal Board in December, 1948 during a period of acute coal shortages. The Company took over the holdings of what were known as the Olstan and Northumberland Collieries, situated at Fassifern, alongside Lake Macquarie and adjacent to the Great Northern Railway, within easy rail access of Sydney and Newcastle, as shown on the locality plan (Fig. 1).The Company was developed in order to produce steaming coal for the power house trade and has continued its activities in the steaming coal trade since its inception. The Olstan and Northumberland collieries were together producing some 300 tons per day when the Company was formed, and it was from this foundation that the colliery was built. The planned development of the Company has been along the lines of producing coal by modern, highly mechanised methods, together with the preparation of theproduct for the consumer, to the highest degree possible consistent with up to date methods.In the comparatively short time of 5t years the mine has developed from a small hand-won coal unit to a high capacity modern mine, one of Australia's largest producers, with an output capacity as high as 3,000 tons per shift.

Jan 1, 1954

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

Two structurally and mineralogically distinct sulphiderich veins cross-cutting the disseminated sulphides of the Nairne Pyrite Member appear to be products of local remobilization of sulphides under fracture-induced free energy gradients during regional metamorphism and tectonic deformation.The contrasting mineralogy of the two vein types may have arisen as a result of differences in the structural orientation of the veins and!or the relative ages of the veins.

Jan 1, 1969

Concentration of Phosphate Ore by Flotation With/Without Desliming

Sep 13, 2010

To George Orwell the year of 1984 was the inspiration for a book. To most New Zealanders it was the year that the fourth Labour Government was elected to power. It was also the year that the review of mining legislation commenced. While Orwell's book and the election of Labour are clearly events of some historic note, one could be excused for classifying the review of minerals legislation somewhat differently in terms of its present achievements! Since the review began it has led a tortuous path through a rapidly evolving policy environment to a point three years hence where no major policies have been determined.

Jan 1, 1987

By D Chappell

Coromandel Peninsula gold mineralisation has an epithermal style which involves extensive alteration of host rocks and addition of pyrite over large volumes of rock. These altered rocks therefore have high potential for generating acid rock drainage. Natural acid groundwater discharges occur in altered rocks, but not in propylitically altered rock. There is little calcite available in mineralised rocks to neutralise this acid. In contrast, the mesothermal veins of the Otago Schist cause little alteration of the host rock, and that alteration has similar mineralogy to the host rock. Calcite is a common mineral in host and mineralised zones, and sulphides are generally subordinate. Hence acidification of Otago rocks is unlikely. This lack of acidification in Otago facilitates arsenic mobility in solution, up to hundreds of ppm. Arsenic is insoluble under acidic conditions in the Coromandel. Base metals are soluble under acidic conditions of the Coromandel, but they are immobilised by adsorption on to the widespread clay minerals where the solutions are neutralised. Base metals are generally immobile in Otago, but when they are mobilised, adsorption is less effectiveas an attenuation mechanism because clay minerals are rare.

Jan 1, 1998

By Q Yang

This paper describes the design and construction of three 7.2 m span access ramp-tunnels to the three level underground car park of the newly redeveloped Top Ryde City Shopping Centre in northern Sydney. The tunnels were to be excavated without significant impact on the overlying Devlin Street, one of the busiest arterial roads in the Sydney metropolitan area and a major link in the Sydney road network. The interpretation of the geological conditions indicated that the tunnels would be driven in a formation of heavily jointed, extremely weathered to fresh Triassic Ashfield shale with some structural features such as dyke, fault and shear zones identified in the available boreholes logs. Both empirical and numerical methods were used to design the tunnels and to predict the ground surface settlements. The design solution, which was influenced by the relatively small scale nature of the work and the current demands on the tunnel construction market, included presupport, initial support and permanent steel fibre reinforced shotcrete (SFRS) lining. The interactions of the driven portals with cut and cover sections and the proposed deep excavation of the new shopping centre were considered at the design development stage and in the construction phase to ensure the safety of the live road. The tunnels have been successfully constructed and are now operational.

Mar 8, 2011

During the course of the major research in the Metallurgy Department of the University of Melbourne into the creep characteristics of lead and .its dilute alloys, it has been the practice to prepare the majority of test specimens from rolled strip. From time to time during the progress of the work, certain variables involved in. the rolling of the experimental ingots have been investigated. It is proposed to collect together in this paper the results of these experiments. Some general features relating to the type of deformation produced have been discussed in a previous paper.While it is admitted that the conditions prevailing through this work differ' in some respects from those of industrial rolling practice, it is felt that many of the factors investigated have an important practical significance. Some of the work described forms a continuation of the researches of R. S. Russell (2) , (3) , (4), into the recrystallization of various pure leads after deformation by rolling.MATERIALS USEDIn this work, a variety of "pure" leads and certain dilute alloys made from the purest of the basis leads have been studied. The compositions of the basis leads and the corres...

Jan 1, 1940

By G Siboni, A Correa De Araujo, M Gotelip Barbosa, M J. Venturini

In support of the development of its Liberian iron ore project, ArcelorMittal Mining Research and Development (AM Mining R&D) has performed characterisation and beneficiation test work on drill core samples received from the proposed mine area. In addition to this, a sinter feed product was composed by blending and processing the drill cores in order to predict sintering performance of the ore. This article presents the methodology used to prepare the drill core blend for characterisation, as well as describe the sinter pot trial. The results are presented, demonstrating how important this type of study is for the development of an iron ore deposit.CITATION:Gotelip Barbosa, M, Siboni, G, Venturini, M J and Correa de Araujo, A, 2017. The use of drill core blends to predict sintering performance, in Proceedings Iron Ore 2017, pp 297–302 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By M A. Mongillo

Most geophysical and geochemical data collected during regional exploration programmes are in vector form (location, value), and have traditionally been presented and interpreted in a profile or contour map format. However, the human vision system can interpret data presented in image format much more easily and new information is often revealed by the judicious application of powerful interactive computer image enhancement techniques. This paper describes a practical demonstration of the application of such tools to gravity and resistivity datasets from the Central Volcanic Region of theNorth Island.   Filtering, contrast enhancement, relief shading, pseudo-colouring and then overlaying of the gridded datasets in image format has helped identify inter-relationships such as the association between many low resistivity anomalies (epithermal deposits or geothermal resources) and the edges of large gravity anomalies (calderas or grabens). Similar revelations should result from the application of these tools to the integration of other mapped datasets from geophysical, geochemical and geological disciplines.

Jan 1, 1992

Nowadays, technology has improved to extract dimensional stone blocks at quarry sites and also to process these at processing plants for making slabs and tiles. In the process of quarrying and processing, performance evaluation of machinery is very important to achieve optimum output at minimum cost with improved technology. Cost analysis of improved technology includes parameters such as manpower, energy consumption, tool consumption, depreciation, maintenance and also others. The chainsaw machine with long boom and rail in marble quarries and multi-diamond wire saw machine for slab making from granite blocks at processing plants have recently been introduced in India. Thus, a study was carried out under a research project on these machines to assess their suitability. In this paper, performance evaluation and cost analysis of chainsaw and multi-diamond wire saw have been carried out with existing machines on the basis of research findings.

Dec 6, 2010