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IF lead be heated with concentrated sulphuric acid two distinct actions will usually be observed. In the first, bubbles begin to be evolved more or less rapidly from the lead, and in the second, which occurs at a higher temperature than the first, hydrogen and sulphur dioxide are evolved, free sulphur is liberated, and leadsulphate is formed. The second action may be violent and usually continues till the lead is all consumed.Attempts have been made to apply these reactions, by means of a standard procedure, as a "Flash test" for the acid resisting qualities of chemical sheet lead. The purpose of this article is to comment on the best method of performing the test, on the various phenomena which may be observed during the course of it and on the interpretation of the results when obtained.PREVIOUS WORKIn 1919, Barr...

Jan 1, 1930

By Meyer T

Sunburst PCF (Penetrating Cone Fracture) technology has recently undergone extensive underground field trials at Leinster Nickel Operations, Western Australia. Trials with the Sunburst machine started in September 1994 and continued through to December 1994 during which approximately 130 metres of tunnel were developed. The Sunburst technology was used to excavate sub-levels through ultramafic nickel ore for future sub-level caving operations at the Perseverance nickel mine. The Sunburst machine demonstrated reasonable instantaneous advance rates, however, there are still a number of future developments/design changes which need to be addressed prior to the PCF technology being trialed again in a production environment. This paper benchmarks conventional drill and blast at Leinster against the Sunburst Excavator machine performance within similar tunnel dimensions and rock conditions. In addition to productivity and cost information; environmental considerations, support and labour requirements are also discussed. Problems with the current machine design are highlighted and possible future design changes are suggested. The Sunburst machine could be a suitable technology for advancing development through weak to moderate rock conditions and may also reduce overall support costs. With the potential for automation and the ability to reduce rock damage into the development tunnel walls, it is proposed that the Sunburst machine warrants further consideration.

Jan 1, 1995

By Carras S, Kelsey P, Caccetta L

An important problem in open pit mine planning is that of detennining the optimum ultimate pit limits of the mine. These limits are that contour which is the result of extracting the volume of material which provides the total maximum profit while satisfying certain practical operational requirements such as safe wall slopes. The determination of the optimum pit contour provides information that is essential in the evaluation of the economic potential of the mineral deposit. A number of optimisation techniques are available for determining this contour with the Lerchs-Grossman and the Network Flow methods being the most favoured. Unfortunately, direct application of these techniques to large ore-bodies may cause considerable difficulties because of the computational time and storage requirements. In this paper, we present a strategy for resolving these problems, and the associated pit design software PITOPTIM (incorporating a fast network flow technique) and a data reducer, BOUND. The results presented highlight the speed and power of the software package rivalling the popular Lerchs-Grossman technique. An application of the software for a sensitivity analysis is also presented and discussed.

Jan 1, 1991

By Anderson JDC

Opencast Lignite Mining requires topwall strata of seams to be fully depleted and footwall aquifers sufficiently depressurized. To prevent a spread of the cone of depression into protected wetlands some distance away, alternatives had been investigated such as closing water works, underground slurry wall barriers and recharge by infiltration. As a result of these investigations, the infiltration method has been chosen and in a first phase during the next decade it will utilize as much as 55 x 106 m3/year. Using this approach, the survival of the wet lands is assured.

Jan 1, 1988

This paper examines the methods and people required for the evaluation of project or corporate acquisitions. Experience over the past five years has shown that some growth can be achieved by carefully evaluated acquisition of gold projects within regions where the acquiring company has gold processing facilities. Many Western Australian companies have participated in this process and the trend seems likely to continue with a diminishing number of larger producing companies controlling through joint venture or direct purchase of widely spaced ore deposits. In some cases the acquisition may include ore processing facilities, however an increasing number of smaller project acquisitions, involving small open pit gold deposits, which are within trucking distance of the acquiring company's mill. Whilst gold prices remain at the current depressed level we can expect to see this trend continue.

Jan 1, 1989

Rehabilitation has been very effective in the short to medium term in providing a cost effective and reliable means of containing the side effects of land disturbance. However, there is still insufficient data to critically evaluate the sucess of rehabilitation in the long term. There is an urgent need to develop objective criteria to monitor the sucess of rehabilitation. The aim of rehabilitation in Australia has traditionally been to return disturbed land to natural vegetation compatible with the surrounding area. This objective has often been accepted instinctively without adequately addressing alternatives.

Jan 1, 1992

Automatic sampling and weighing of copper sulphide concentrate produced on Bougainville Island (PNG) is described. Contained metal weights gave satisfactory agreement with buyer's results after the introduction of polyethylene lined sealed aluminium foil bags for transport and storage of assay samples. Paper bags used previously for this purpose permitted oxidation of the sulphide concentrate and thus caused lower assay values.

Jan 1, 1976

There are two main areas of application of geology in quarrying: (i) In regional planning for industrial mineral requirements.(ii) In direct quarry management. The regional planning requirement has recently become more evident because of greatly increased land demand conflicts around cities. The direct quarry involvement is a reflection of both the economy and the greatly increased sophistication of the quarry industry. Here, professional planning and development expertise by a geologist is required, to ensure continued supply of raw materials at the best price to the consumer with sufficient profit to the producer. Today, geological insurance safeguards capital investment in plant and assures economical development plans.

Jan 1, 1978

In July 1994 the Premier, John Fahey MP, announced that the New South Wales Government would make available a total of $40 million over six years in new funding for the Department of Mineral Resources. These funds are to be applied directly to the generation of regional geological and geophysical information. The Government's initiative known as `Discovery 2000', is aimed at providing a major boost to the exploration industry. The Government expects new discoveries to be made and new mines to be developed because of the initiative and, perhaps, the first ever commercial oil or gas production in New South Wales. The Government's return will come from increased economic activity, and from the increased royalty return from higher levels of production. Quality information is the key to successful exploration. In the highly competitive business of mineral and petroleum exploration high quality regional geological and geophysical information improve both the efficiency and effectiveness of the area selection or project generation process. Using the `needle in the hay stack' analogy, Discovery 2000 will vastly improve industry's chances of finding the haystacks. It is up to the mineral and petroleum industries to find their respective `needles'. Careful target area selection is probably the most critical factor in mineral exploration. The ability to select the most prospective areas, or to identify prospectivity that others have failed to recognise, can make all the difference between success and failure. Government geological surveys clearly have a crucial role to play in providing the geoscientific information infrastructure that companies must have if they are to make the discoveries this country needs to pay its way in the world. It is the regional information generated by Governments that sets the scene for efficient exploration. This regional information includes regional aeromagnetics and radiometrics and gravity, regional geological mapping and tectonic analysis, and geoscientific databases. The New South Wales Department of Mineral Resources (by various names) has been providing such information for over 100 years and has led the way in many aspects of the generation and dissemination of geological, geophysical and metallogenic Information.

Jan 1, 1995

By McKee DJ

Future mineral processing developments will be of two types. There will be a continuation of the advances of the last 20 years including major increases in equipment capacities, the development of reliable on-line instrumenta- tion, the use of digital computers for automatic control, and the greatly expanded use of in-situ leaching techniques. However, there will also be a need for innovations as the industry faces a different set of problems to those involved in cost and extraction efficiency considerations. These new problems include those relating to energy usage, environmental pressures, and the further development of large low grade deposits and small, high grade metallurgic- ally complex deposits. Present technology does not appear adequate to solve many of these new demands. New treat- ment concepts will be required, and the immediate outlook in this regard is not encouraging. A major research and development task in mineral processing over the next 20 years will be to seek out new ideas and develop them, and this must be pursued with imagination and determination. Both the continuation of the present research pro- grammes and the development of new methods will require a steady supply of highly qualified technical personnel. These people are not being produced in the numbers required, and this situation must be urgently rectified.

Jan 1, 1981

The process of resource estimation of large precious metal deposits is illustrated by reference to major deposits now being mined or developed by Placer.The estimation procedure commences with building an appropriate model of the mineralization and proceeds through steps of data validation and geostatistical studies. It is important that the geologists most familiar with a deposit be involved with all stages of the estimate, and also prepare a manual estimate used to validate the kriged resource.Resource estimates are major exercises taking many man-months of work. The most time consuming part of this is usually construction of an appropriate three dimensional geological model. The data base for the resource calculations must be complete and checked for accuracy. The most appropriate estimation method must be selected.

Jan 1, 1990

Prefeasibility planning and cost estimation of conveyor systems has historically been undertaken by comparing fi xed plant transport requirements to that of similar systems in service. This paper describes the development of a prefeasibility conveyor technical design and cost estimation application using Microsoft Excel Visual Basic for Applications (VBA) platform. The application tool known as D-Convey (Dachshund Convey) was developed with the goal enabling the end user: to develop a technical model for conceptualised conveyor systems, to perform economic analysis on the developed technical model, and to conduct a comparative and risk analysis. An Excel VBA based platform was utilised to draw upon both the analytical and graphical capabilities of a spreadsheet. Some of the features of D-Convey system include a revolutionary dynamic graphical help system, known as the 'information pane' in lieu of traditional help fi les as well as the use of familiar graphical user interface elements such as the MS Offi ce 2007 task ribbon. The D-Convey system incorporates material database allowing for mass handling prefeasibility estimation in other industries; it has been validated at a local quarry.

Dec 6, 2010

As a basis for my address to you tonight I thought it might be opportune if we considered the great history of the mineral industry in Australia, and the contribution it has made to the development of the country. While it is perhaps interesting to review the achievements of the past there is also the opportunity to examine the developments of the future.The names generally given to the three periods of man's life on the earth-the Stone, the Bronze, and the Iron Ageand to which should perhaps now be added the Atomic Age, imply the vast importance of the progressive steps in 'man's discovery of minerals and the means of working them. They tell the story of his advance from the flint knife to the bronze celt, and then to the keen-edged iron weapon, and now to the possibilities of the peaceful application of atomic energy. Not only have the stories of gold, iron, copper and tin told a great deal of the history of the progress of mankind, but they have also traced the commercial and industrial growth of Australia over the last century.Gold in the 1850's was responsible for the most significant period of immigration Australia has ever had-when the population almost tripled in the ten years to 1860. Minerals were also responsible for opening up Australia and determining the pattern of settlement. As mineral finds were made, railways were constructed to these fields, then agricultural development followed.Then, as the industrial era started, minerals provided the raw material for Australia's rapid industrial expansion, and they have all contributed to the extent that they have made...

Jan 1, 1960

By Harraway D. H, Draper N

The association of graphite with a fine grained pyrite in the Mount Isa lead-zinc ore was investigated from mineralogical and metallurgical standpoints. The pyrite has been partially or completely replaced by galena and to a less extent by sphalerite, pyrrhotiteand chalcopyrite with the retention of graphite films or inclusions. During lead flotation the graphite imparts a spontaneous flotability to all associated minerals, resulting in a low grade fraction, which we call the carbonaceous fraction, floating with and diluting the lead concentrate. In times of low metal prices this fraction seriously reduces the economic value of the lead concentrate. A flotation procedure was developed to upgrade the carbonaceous fraction separately, producing an economic concentrate and a tailing.INTRODUCTIONThe lead concentrate produced from Mount Isa ores can vary from 20 to 50 per cent lead, depending on the locality in the mine from which the ore is obtained. Variations of this order are independent of ore grade and lead recovery. The large variation is related to the presence in the ore of a variable fast floating low grade fraction known locally as the carbonaceous fraction because of its association with graphite. During conventional lead flotation with sodium ethyl xanthate the carbonaceous fraction floats rapidly and unselectively with normal Mount Isa galena.The paper discusses mainly the examination and treatment of an average carbonaceous fraction, defined here as the fast floating material in the mill feed of late 1956. The ore was drawn from the Mount Isa Black Star orebodies. The fraction represented about 5 per cent of the total ore...

Jan 1, 1961

The Ardlethan tin concentrator had dete riorated considerably in metallurgical per- formance, maintenance and plant availability. This problem was compounded by low tin prices and International Tin Council quotas. Mid- 1976 figures were: throughput - 1300 tonnes per day, availability 83% and metal recovery 537. Major problems existed throughout the circuit from crushing to tailings disposal and with morale, staffing, and housekeeping. With the lifting of the quotas in June 1976, management provided funds to implement a major rehabilitation programme and some fifteen major projects, at a cost of about $1.3 million have been completed to date. The change in performance has been dram- atic, and end of 1977 performance figures are: throughput - 1700 tonnes per day, availability 90% and metal recovery 65%.

Jan 1, 1978

Computers are playing an increasing role in the management of technical data in mines. Companies are re-assessing the role of their data processing departments as users demand computer resources in non-accounting areas. Data of all kinds is now being seen as a, company resource, and the role of computing professionals is to help to manage the data flow, not merely to manage computers. The concept of distributed data bases puts the responsibility for data entry, editing and updating with the user. This challenges conservative views of centralized control of computing, suggesting, instead, centralized co-ordination. A survey of the possible applications of computers in technical areas points up the special requirements of handling raw, processed and consolidated technical data. Technical data bases have become flexible as mini- computer hardware and software have rapidly developed. Management has the ultimate responsibility for efficiently administering corporate data bases, and it must ensure suitable policies are developed for this purpose, with enough flexibility to cope with the impact of fast changing technology.

Jan 1, 1980

Gunpowder Copper Limited processes 1,000 tonne/day of Mammoth ore in a conventional flot- ation concentrator. Run of mine ore is prepared for flotation by three stages of crushing and two stages of ball milling. The concentrate, in which the primary copper mineral is chalcocite, is solar dried and exported to Japan. The history of operation is summarised, and plant practice and metallurgical problems are discussed.

Jan 1, 1974

Mining and metallurgy are more capital intensive than all other industry in Australia. Capital demands are met by domestic and foreign sources of finance for whom the major constraints are the supply of funds and factors of risk and uncertainty. in both mineral development and institutional financing policies, specific options are available to administrators which would allow mining to benefit from a more reliable supply of capital. The strength of major partners involved and overseas participation are important aspects of financing mineral developments. Future changes in financing for the mineral industry are considered most likely in variable interest rate funding, in the leasing of major plant items, and in the development of flexible techniques to ease the burden of infrastructure costs. In a consultancy sense, financiers are available to mining to assist with and to advise on optimal develop- ment of mineral industry projects.

Jan 1, 1975

The calibrated thermal IR data of part of Cambay Basin is used to determine surface temperatures and to detect the heat flow. Applying the conductive heat flow continuation technique, the three dimensional configuration of the hydrocarbon bearing reservoir was defined. The zone delineated by the present study coincides with the oil-bearing structures inferred by seismic survey. The results indicate the possibility of the technique as an effective tool in hydrocarbon exploration.

Jan 1, 1986

Difficult ground conditions in the area planned for placement of vent rises to the surface at the Porgera Goldmine led engineers directing the project to chose blind shaft boring methods of shaft construction from the available alternatives. Zeni Drilling Pty Ltd was first contracted in 1988 to install a group of three closely-spaced, steel lined shafts. The success of these led to an order for a fourth hole in the same group followed by two more, less than a kilometre. away, under a separate contract in 1992. All of the shafts were completed on.schedule to within one day. The only significant difficulty arose during commencement of the last shaft when the strata collapsed trapping the drilling tools and jeopardising the stability of the surface collar pad. The situation was corrected by innovative lining techniques and the project went on to finish on schedule. This paper discusses the application of various technologies associated with the project including aspects of geotechnical input, drilling fluid chemistry, mining engineering and logistics.

Jan 1, 1993