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In undertaking to write a few notes on practical mining in Bendigo, the great quartz mining centre of Victoria, which just now is celebrating its fiftieth anniversary of gold mining, satisfaction must be expressed which is, no doubt, shared by all mining men and inyestors, that Bendigo has not lagged behind other Australian mining districts in the evolution of mining from its crude state, subsequent to the discovery of gold in 185 to its present more perfect state; and though it may be said that it has not yet reached the high pinnacle of perfection towards which advanced science and change of conditions may yet lead it in the course of future progress, yet, what has already been done in this respect, the adoption of the most approved methods appliances and modern machinery, tending towards greater and still greater efficiency, facility, and economy in our mining industry, must be accepted as a guarantee that in tne future as well as in the past, progress in our means of developing our mining resources will ever remain our watchword, by means of which future difficulties will be overcome as well as they have been removed in the past.The adoption of this principal, combined with a study of rigid economy, has raised gold mining here, as well as in other places, from a state of speculation, and sometimes wild speculation, to the status of a solid, stable industry, the strong supportand backbone of the country in which it flourishes. Two of the principal factors which have been to a great extent instrumental in bringing about this satisfactory state, must be specially mentioned.

Jan 1, 1902

Lean Iron Ore Beneficiation in India

Sep 13, 2010

The concept of "profit" is implicit in the definition of an ore reserve. It is suggested that the flexible concept "economic" is more appropriate. This allows different economic considerations to be taken to account when determining what is ore at the feasibility study stage; during actual mining production; before mine closure; and from the viewpoint of the national economy. Economic factors which are highly variable, and largely beyond a mining enterprise's control, affect the economic exploitation of a mineral resource. Major economic factors include: metal prices; operating costs; the cost of original and replacement capital equipment; the cost of capital; taxation and royalties; inflation; exchange rates and the state of the world economy. The paper suggests why a careful quantification of the average value, trend, and variation from the trend of major economic factors should be made and how this will lead to a better definition of ore reserves. The paper also discusses the necessity of reappraising economic factors during the life of a mine in order to maximise the economic surplus and to minimise the wastage of natural, economic and human resources employed in mining.

Jan 1, 1979

By Selby DW, Hamill J, Cauley ID, Thomas I, Thornton AJ

The main objective of sulphide flotation in a cassiterite concentrator is to remove sulphide minerals (pyrite, pyrrhotite and sometimes chalcopyrite) from the ore prior to gravity concentration. Tin losses in the sulphide flotation stage account for a significant proportion of the total tin loss. separate studies of the sulphide flotation circuits of Renison Ltd and Cleveland Tin Ltd were conducted to investigate reasons for the tin losses. Sampling surveys were conducted in the rougher-scavenger and also the regrind-cleaner sections of both plants. In both plants, the rougher circuits recover excessive quantities of liberated cassiterite, while recovery of the desired composite cassiterite-sulphide fraction is low. The regrind mills are successful in liberating the composite cassiterite in the rougher concentrate, but at the expense of increasing the proportion of very fine tin mineral. The cleaner circuits recover between 40 and 60% of the cassiterite received, and this is all lost.

Jan 1, 1978

By S Choy

Aquatic macroinvertebrates have been used as a monitoring tool for many years. They are ubiquitous and occupy a central role in the ecology of rivers. They are a key link in the aquatic food chain, forming a pathway between primary producers (such as algae and macrophytes) and predators (such as fish, platypus and birds), and some are sensitive to flow conditions, water quality and habitat condition. They are not very mobile and are good indicators of local impacts. As most aquatic macroinvertebrates are benthic, they are better able to integrate effects of changes in water quality, and habitat condition and structure. Their diversity is crucial to the maintenance of a balanced, functioning and healthy river ecosystem. Thus, data on benthic macroinvertebrate community structures can be used for predicting potential impact, assessing the extent of damage and for gauging recovery from damage. Over the past eight years, State agencies throughout Australia, through the National River Health Program have developed models (AusRivAS) to assess river health using macroinvertebrate communities. The Queensland Department of Natural Resources and Mines has sampled both macroinvertebrates and water quality throughout Queensland, including areas affected by mine discharges. This paper will assess results obtained from sampling in the Mt Morgan area to illustrate the usefulness of this method of river health assessment.

Jan 1, 2003

The optimisation of capital in the total planning context has broadly two components: ò maximising the efficient utilisation of capital against competing capital demands; and ò maximising the efficiency with which the industry's capital requirements are sourced. This paper focuses on the latter of these two concepts, as I wish to highlight that within the coal industry the inefficient sourcing of capital has resulted in the inefficient utilisation of capital. In discussing the optimisation of capital within the coal industry I would like to outline three fundamental issues which currently impact the industry and its application of capital: Initially, from the perspective of an independent investor, the perceived risk associated with investing in a volatile industry cycle has not permitted appropriate funding structures to be created thus leading to an inefficient utilisation of capital. Secondly, investors seeking out a windfall gain have established a practice of trading in the assets rather than encouraging recapitalisation. And lastly the mismatch of supply and demand leading to the establishment of new projects which include a percentage of offshore investment has fostered an environment of lower returns and subsequently a dilution of capital.

Jan 1, 1991

University education in Australia is changing, driven by greater market orientation, reduced funding available per student, especially in the higher-cost minerals industry disciplines, and the call for more flexible delivery of subjects and courses to meet changing lifestyles and expectations. The opportunity exists for a true partnership to develop between industry, government and academia that will reshape minerals education in Australia and secure the future supply of the specialists industry needs to maintain international competitiveness. If this partnership does not emerge, it is anticipated that AustraliaÆs somewhat fragmented and unstable higher education system, especially in the disciplines of particular relevance to the minerals industry, will be put under further pressure so decreasing its effectiveness to produce quality graduates. The Minerals Council of Australia in 1998 published æBack from the BrinkÆ, a discussion paper which proposed strategies to build a world class minerals tertiary education system in Australia. Those strategies are now being implemented collaboratively with principal emphasis on the disciplines of mining engineering, metallurgy and earth science and as far as process is concerned, on the necessity to æcooperate to competeÆ. For metallurgy, the challenge is to integrate more closely undergraduate teaching with the existing world-class research centres and to link the tertiary institutions in such a manner that the strengths of all components are harnessed and then made available nationally in major population centres and at remote sites where appropriate. For industry the challenge is to build effective partnerships with the academic community that will enable and assist the agreed course of action to take place.

Jan 1, 2000

The mine manager is one of the oldest jobs in the world. Over many centuries the fundamentals of how this job was approached did not change much. However since the later part of the 1980s there has been a dramatic shift in the expectations and role of the mine manager as the pressures of globalisation and consolidation have increased the size of companies and the production levels of mining operations. The changes have been dramatic, with demanding requirements on mine managers to continually improve the skill levels of people, to apply and develop rapidly changing technologies and to consider far broader business issues that need to be managed in a truly globally connected world. This paper will attempt to outline some of the issues, the complexity surrounding them and some of the approaches that have been made to manage them. There is not a single correct answer or approach, but there are many key success factors that have led to some amazing levels of performance being achieved as we go deeper, broader and literally move mountains to meet the customerÆs needs for today and tomorrow. This contrasts with many mining operations in developing countries that still have a traditional approach to how they mine. Society is the river of life that continually flows and changes the environment that surrounds it. The pressures from the customers and world growth, shape and force alterations to be made in an industry that has to live with the far greater primal and uncompromising forces of the earth we mine. This has led to some paradigm shifts in how we accept what we manage. TodayÆs mine manager must manage a far broader range of issues, than just how do we get tonnage out of the mine and product out of the ore. These include but are not limited to technical, commercial, product quality and end use understanding, employee and community issues, environmental and the ever increasing complexities of sustainable development. Organisations will have to look at how they structure their management of the business to manage functions to meet the complexity of different stakeholders needs û the business, the employees, the customer and the broader community within an environment that is becoming more attuned to the harm impacts to the world in which we operate. The attraction and retention of skilled people that contribute to the value and worth of the corporation, will become critical to sustain a companyÆs growth. One of the fundamental elements of successfully doing this will always be the skills of the mine manager and his/her extended team with the continued development and support that they will need to meet these demands.

Jan 1, 2006

By Schneider CL

The calculation of the liberation spectrum in the product from continuous milling operations is a problem of considerable importance, and it is difficult to solve because the population balance equation must be integrated in two-dimensional space. Complete solutions require a very detailed knowledge of the complex interactions between the fracture patterns and the mineralogical ore texture when brittle particles are subject to impact fracture. Most of the liberation models that have been developed to date apply only to batch comminution processes and under these conditions the liberation problem can be studied in isolation. When the comminution is continuous and forms a unit operation in a flowsheet that includes classification and separation operations, the situation is very different, and then the liberation of the minerals must be described when single particles of known mineralogical composition are fractured. Important industrial examples are conventional milling circuits closed by hydrocyclone and regrind mills in flotation plants. This paper presents an efficient computational algorithm for the calculation of the liberation spectrum produced by continuous milling operations. The algorithm relies heavily on the detailed internal structure of the Andrews-Mika diagram. The modifications that are required to make this diagram apply to practical ore minerals, and the internal structure of this diagram can be established using single-particle fracture on mono-size, mono-grade material but suitable liberation models are essential to interpret the data in terms of the cross transfer coefficients required for the population balance procedure. Models proposed by Leroux (1992) and King (1990) are compared to experimental data.

Jan 1, 1993

The purpose of any feasibility study is to determine whether a particular investment or management program will enhance shareholder wealth by, for example, producing an economic return in excess of the cost of equity capital.The threshold rate of return conventionally used in gold feasibility studies is higher than the cost of equity capital, meaning that some viable projects are wrongly described as being sub-economic with their development deferred.Is the industry failing to fully realise its potential? Aside from important technical considerations that determine the cost of exploiting inground inventories, feasibility studies need to incorporate expectations about future gold prices, exchange rates, interest rates and tax rates.Rather than revert to speculation, insights from capital markets give a rigorous framework in which these parameters can be determined for feasibility purposes. Separate questions sometimes, and then inadequately, addressed by feasibility studies include: ò Is it optimum? Many projects are expanded soon after project commissioning - what does this say about the quality of the initial feasibility study? Moreover, does the rate of extraction really matter? ò What is it worth? Although feasibility studies are designed to address viability rather than valuation, such studies are never- theless used by the industry as further evidence that the equity markets have got it wrong again! More likely the problem is with the financial slide rule being used. ò Can it be debt financed? The bankable feasibility study has entered the vocabulary of the gold mining industry but what does it mean? Does it matter anyway how the project is to be Financed?

Jan 1, 1991

By Porter I

Rock mass classification systems have emerged as a powerful tool which can be used for assessing ground conditions and determining support requirements in underground mines. They should not be used as a substitute for complete engineering design, but rather as a supplement to observational methods and analytical study. In general, the use of rock mass classification is attractive, but each classification system has various deficiencies. Use of any particular system should be made only with knowledge of that systems limitations. It is desirable to employ a number of systems and design methods which will allow for comparison and lead to a better understanding of the rock mass condition.The Rock Mass Quality system (Q-System), developed by the Norwegian Geotechnical Institute, and the Rock Mass Rating (RMR) System, Bieniawski, were designed primarily for civil engineering structures. Laubscher et al (1978) further developed the RMR-system specifically for rock mechanics engineering in the mining industry. A method of stope design, which introduces a stability factor for the rock mass and compares this with hydraulic radius, was developed by Mathews et al (1981). This paper reviews the above systems by applying them to stability assessment of crown pillars in two Australian metal mines and provides a critical analysis of the various approaches. In particular each system will be analysed to determine its suitability for use in crown pillar design. The most suitable system(s) will form the basis for future development in crown pillar stability analysis.

Jan 1, 1994

The underground mining of a narrow vein hard rock orebody is a capital and labour intensive method of extraction. Due to the nature of underground mining it is difficult for higher level managers to physically see the efficiencies and inefficiencies of a particular method. Extraction methods and sequencing often need to be altered from the original planned methods as a result of mine developent, providing more in depth information as it progresses. As a result of these issues contract mining of these orebodies is common practice. There are several types of contract structures for the purpose of underground contract mining with many complex permutations of them that reflect the different needs of each individual company and orebody. The different contracts are arranged dependent on the mining companyÆs desire to transfer or, alternatively, embrace risk. This presentation gives a brief overview on these different methods and their various advantages and limitations with regard to small scale and narrow vein underground mining. With respect to these different contracting methods, the presenter reviews the mutual growth benefits of emerging partnering opportunities, specifically with regard to smaller explorers exploring and developing prospective mining tenements. The specific advantages to small explorers include the resource flexibility and speed of project development that private mining contractors can provide. Given the contracting methods that are available, there is potential for small private mining companies to gain minor stakes in major projects and major stakes in medium sized projects by employing innovative contracting solutions to provide mutual benefits to the parties. Some potential scenarios to this effect are suggested in the presentation. This paper is available as a PowerPoint presentation only.

Jan 1, 2006

Laboratory studies of batch and continuous screening of ferrous sinter mixtures (4-0.5 mm) are described. The results are analysed by an equation derived from the first-order rate law for the condition of decreasing screen residue.The results of the studies show that the two screening operations are comparable in all respects if deck length in continuous screening and time in batch screening are interchanged.It is shown that the general screening process is determined by the numerical values of the screening rate constants of each of the particle sizes in the feed mixture and that the relationship between these constants and the particle size/screen aperture ratios is related to the appropriate probability function of the same ratios.It is also shown that the screening rates decrease exponentially with the amount of near-mesh material present in the feed and that oversize particles can increase these screening rates for some screen motions and decrease them for others.

Jan 1, 1985

The long continuing controversy over the Origin of fusain, whether it is a product of primeval forest fires, or of special conditions of weathering (including bacterial decay) of the vegetal debris concerned prior to, burial, has now been extended, to include the possibility that fusain is a product of the coalifaction process subsequent to deposition, so that doubt may reach even to its time of formation.The conflicting views on this point are summarised in the following quotations from two recent publications (my italics in each quotation):1. "Recent observations made in peat and brown coal deposits in Australia, England and Germany strongly suggest that practically all fusain is formed by coalifaction after deposition and 'preliminary compression. In deposits of advanced brown coal rank, it normally takes the shape of pieces of wood compressed parallel to the bedding plane; and some fragments consisting partly of fusain and partly of vitrain exhibit the same amount of compression throughout. This would seem to indicate fusinisation after burial, as hard brittle charcoal would be crushed, or else retain its original irregular shape if strong enough to withstand pressure.In some immature deposits, however, where cover is of a hydrostatic nature rather than a vertical compressionar force, occasional pieces of fusinised wood showing very little flattening are present, but such immature deposits seldom contain the proportion of fusain found in higher rank coals. In view of this, and the possibility of introduction of charcoal into peat deposits, it is felt that a small amount of the fusain in coal may represent wood charred before burial, but most of it almost certaInly originated as a product of fusinisation after burial" (Dulhunty, 1948, p.14).

Jan 1, 1953

Investigations of the Mineragraphic Section; Commonwealth Scientific and Industrial Research Organisation, have included most of the known stannite-bearing ores in Australia, and have revealed several new occurrences of this relatively uncommon mineral. They provide information about its paragenesis, and its possible effect on tin recovery, that may be of general interest.Several of the investigations used in the preparation of this paper, were made in the first instance by pr. F. L. Stillwell or in collaboration with him.CASSITERITE-SULPHIDE ORES IN NORTH-WEST- TASMANIA Stannite is a minor component of most of the cassiterite sulphide ores of north-western Tasmania. These include the orebodies of Mount Bischoff, the Cleveland mine, Moina, the Stanley River district, Renison Bell, and the Heemskirk-Zeehan district, and form a well defined metallogenetic provence which is related to the Devonian granites of this part of Tasmania.In these ores mineralisation began. with deposition of cassiterite, a little wolfram, and quartz, topaz and tourmaline. With falling temperature, deposition of cassiterite ceased and arsenopy-rite, pyrite, and especially pyrrhotite, formed in abundance, tending to give massive sulphide ore. A little chalcopyrite; stannite, sphalerite and native bismuth accompanied the pyrrhotite. Deposition of quartz ceased after the pyrrhotite, was formed, and the later-formed nonsulphide gangue consists chiefly of carbonates and fluorite. With, the advent of the carbonates the pyrrhotite was altered to fine-gained intergrowths of marcasite and pyrite. Excess iron from the pyrrhotite entered the intergrown carbonate, or was precipitated as magnetite. Some solution of the cassiterite occurred at this stage, the tin being redeposited chiefly as stimnite replacement rims around the residual cassitellrite grains. Varying, but small, amounts of sphalerite, galena, tetrahedrite and silver minerals were depoSited at this stage, bringing the mineralisation to a...

Jan 1, 1951

By Diehl GW, Kuntonen J

The Tamrock all-hydraulic rock drilling system 400 has been developed to cover as wide a drilling range as possible, from 35 mm holes in tunnelling, roofbolting and development work to 64mm holes in long hole production drilling. Field experience during the last five years shows that the Tamrock drill covers this range in a way that no other rock drill on the market does and recently the range has been success- fully further expanded to cover bench drilling with 76 mm holes.

Jan 1, 1978

I have been asked to speak today on the topic of Project Finance in the Mining Industry. Through this presentation, I hope to give you a broad outline of the concept of project finance. The first half of the presentation covers the principles involved in project finance and the second half moves to aspects more specific to the mining industry. I have worked for 3 years at Rothschild Australia. Rothschild provide finance for projects in the mining industry, world wide. We finance both large and small projects, with facilities varying from $2m to $100m.

Jan 1, 1990

This is the second of a series of papers dealing with Geology in Exploration. The first, published by the Australasian Institute of Mining and Metallurgy, Proceedings Nos. 143-144, 1946, was written as an introduction to the subject and employed the exploration geology of the Cobar field to illustrate the prospect thinking. This paper will be concerned with the problem of ore repetition in depth and borrow its- example from the Mount Lyell copper field. The writing will be taken up altogether by the example. Nevertheless the intention remains to develop the subject in terms of its wide interest and application.The Mount Lyell field possesses large actual and prospective resources within, and in the vicinity of, the known deposits. This paper does not bear at all on these accessible ore reserves and tangible prospects. There is also in this area evidence of deep ore. The possibility is of little practical interest at present. But the picture of ore repetition, exemplified by the Mount Lyell field, does matter now to the outlook on exploration in this country. For once this essential feature of ore occurrence is widely understood there may develop, on the scale warranted, the search for major deposits which do not outcrop but which are still at shallow depths because of the part erosion plays in this story of concealment and exposure of ore. Also there is the chance in some fields (including Mount Lyell) of a second harvest of orebodies within mineable depths. This exploration goal, introduced in the first paper, will appear more clearly as the Geology in Exploration series is written up. Here the concern is to show the character of the geological evidence which points to the occurrence and recurrence of ore in the earth's crust, the picture at the foundation of this exploration scheme. There is considerable information in the Mount Lyell area of the structures...

Jan 1, 1947

The Australian underground contract mining industry has grown from almost nothing 25 years ago to the point today where half the countryÆs underground mines are using contractors to produce their ore and do their development. This growth was driven by the need to change poor industrial relations and work practices in sectors of the industry, along with the needs of many small gold mine owners to preserve their capital by using contractors to do their mining. The industry is dominated by two major privately owned contractors with a number of other publicly and privately owned contractors making up the balance of the market. This paper discusses the important trends in the contract mining industry and the directions it may take in the next few years.

Jan 1, 2005

By J Shooter

Pezzimenti Laserbore designed, fabricated and commissioned the first microtunnelling machine in Australia in 1986. The System was initially a very basic one, developed in isolation to the overseas explosion in microtunnelling growth headed by Japan and Germany. Market needs in Australia have demanded increasing flexibility in microtunnelling capacity-longer distances, variable ground conditions and larger diameters. The one constant throughout the development process is in maintaining high accuracy û the attribute which most readily differentiates microtunnelling from other limited steering techniques.This paper will highlight the features of microtunnelling by drawing on case studies of completed projects.

Jan 1, 1999