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This case study reviews the Charters Towers vein systems for potential open-pittable bulk tonnage resources in' stockworks, horsetails or multiple vein systems. The review summarises district evaluation undertaken over the last 18. months before specific drill evaluations.Historical mining from Charters Towers includes in excess of six million ounces at head grades of one ounce per ton. A review and structural studies show most veins as simple, tight systems without significant horsetails or multiple sheeted systems. In addition the normal gold content of the pyritic selvages ('formation') is low and disseminated gold is virtually absent. Shoots are structurally controlled on vein/vein and vein/contact intersections. Historically high production vein systems are hosted by .,.t o of the younger granodiorite phases.Geometrically most veins dip shallowly (from 45¦ to as low as 200) in a north or easterly quadrant. Flat dips permit open cut exposure of considerable vein area at a favourable stripping ratio.

Jan 1, 1986

Erosion of unprotected batters, spoil banks, slopes, and stockpiled material creates a multitude of environmental problems. Winds blowing across these denuded surfaces can generate dust clouds capable of depositing un- desirable particulate material a considerable distance from the source. Water eroding these areas continually exposes new surfaces which may be oxidized. Iron pyrites can be dissolved in the flowing water, resulting in the addition of pollutants to streams and water sources. Silting of water sources can also occur as a result of this erosion. Valuable topsoil can be blown or washed away. In addition, the after-effects of erosion leave a visual pollution which is more difficult and expensive to correct than to prevent.

Jan 1, 1976

Mount Isa Mines operates Hewlett Packard 1000 computer systems for process control in its major mineral processing plants. To simplify control systems implementation, a process control software package has been developed. This package is now used at the Lead/Zinc Concentrator where the HP computer is interfaced to Foxboro Interspec/Spec 200 system and Honeywell TDC 2000 front-ends. The HP computer controls crushing, grinding, flotation and tailings disposal. This paper outlines the development of process control systems at Mount Isa Mines. The creation of the process control package is described and the reasons for its development highlighted. The application of the software package and the implementation of process control systems at the Lead/Zinc Concentrator is detailed.

Jan 1, 1978

By T C. Hunter

There are unique risk factors involved in the development of an Australian uranium project especially by a æjuniorÆ. These encompass a range of political, technical, environmental, regulatory, timing, native title, investor relations and financial issues. The Honeymoon Uranium Project in South Australia is being developed by Southern Cross Resources. The history and experience from a risk viewpoint is detailed and discussed. Particular emphasis is placed upon the practical experience and obstacles overcome to meet project milestones.

Jan 1, 2003

Competition in the mining industry is the main driving force for both equipment manufacturers and end users to develop and apply the most cost efficient solution to a mining problem. Therefore the challenge to find new solutions is usually met by several suppliers under various factors of influence affecting specifications. Time and timing are particularly important, but all new developments ultimately have to successfully perform on site.Consideration of all aspects of planning, manufacturing, user liaison and ultimate satisfactory commissioning hinges on the necessities of assessing of all the expectations in the mining application and the requirements of the concept and layout team. To apply the maximum available technical competence with solid thorough workmanship is the best possible foundation for success of underground machinery development.

Jan 1, 1991

By J Szymanski, S Planeta

In pursuit of optimising the cemented rockfill system fragmentation of the aggregate, while travelling through the surface-to-underground aggregate transport raise, was investigated and a æfines estimationÆ equation was determined. When used with the rockfill strength estimation equation, the fines estimation equation enables an accurate estimation of the compressive strength to be derived theoretically. Optimum fill raise orientation was examined and recommendations are given depending on the varying stope dimensions. If the maximum dimension of the stope is less than 30.5 m (100 ft), a single, centrally located fill raise will suffice. However, as the stope dimensions increase, the number and orientation of the fill raises becomes more complicated and each stope must be examined on an individual basis.

Jan 1, 1998

The concept of Extreme Gravity is the latest in a series of innovations that has seen a re-introduction of gravity recovery systems into the milling operations of most gold mines. Traditionally, most gold milling circuits are designed around flotation and cyanidation requirements, with the gravity circuit being fit in where possible. Extreme Gravity takes the novel approach of optimising the circuit, in order to maximise recovery by gravity. In some cases gravity systems can achieve high enough recoveries to eliminate the need for chemical systems such as cyanidation or flotation. There are many advantages of such a system including low capital cost, reduced permitting, improved cash flows and much reduced environmental issues. There are a number of plants currently in operation which utilise this new methodology. The Muzhievo project has been an example of a recent turn key success achieving recoveries from 85 - 90 per cent. The details of this project are examined as a case study.

Jan 1, 2000

Water is required as a key strategic resource in most mining and metallurgical processes and, in some countries, it has become a limiting supply for the development of mining activity. During the last years, mining industry efforts have been successfully focused on water use efficiency in the different processes. However, these efforts will not be sufficient to compensate for the growing demand of mining products and the decrease of ore grades. New efforts should be oriented to the search for alternative water supplies such as sea water, with or without desalinisation, or water harvesting. But to survive this growing pressure and to get a social licence to operate, the mining industry can also assume a proactive attitude and pursue a prominent role in water management at regional and local scale. This paper reviews some of these emerging issues, particularly in the context of the Chilean copper industry.

Jan 1, 2009

The word "mine" means different things to different people. To a professional in the mining industry, it may mean trucks and shovels, overburden dumps, headframes, mill buildings, and the other conventional nuts and bolts that constitute an operating mine. To an environmental- ist it may mean bulldozed trees and tailings dams. To a mining engineer who has spent a significant proportion of his career in mine and prospect evaluation, it can mean a hole in the ground with a liar at the top. The liar in this case is frequently not so through design but through ignorance. The purpose of this paper is to contribute in a small way to en- lightening that ignorance. In doing so, it will foster more effective deployment of the pool of risk capital available to the industry.

Jan 1, 1982

Clearly visible in geophysics is a trend away from simply finding and drilling anomalies obtained with off-the-shelf equipment, condes- cendingly sold by travelling salesmen. Instead, technical tools are becoming available which allow us to choose or design equipment and sur- vey procedures for the specific problem at hand. The advent of micro- and smaller computers enable us to collect more and better measure- ments and to rapidly process them so as to emphasize the features which are being sought. These new capabilities have important consequ- ences both to the extent to which geophysical tools will be applied in the industry, and to the skills which will be demanded of those using them. Because of its uniquely difficult exploration problems, Australia must expect to amplify its new prominence in the development of mining geophysical technology.

Jan 1, 1981

By Hall ST, Miles NJ

Recently an inorganic salt, sodium polytungstate (SPT), has become available that allows the preparation of non-toxic solutions of relative densities up to 3.1. It is relatively expensive and at the higher relative densities achievable, highly viscous. Alternative inorganic compounds may in the future be identified that overcome these limitations. The Australian Mineral Industries Research Association Ltd (AMIRA) has initiated a project to examine possible alternatives. However, it has been found that by the addition of finely divided ferrosilicon to solutions of SPT, relative densities of up to 4.0 can be achieved. A laboratory technique for density fractionation of sized mineral samples utilising this finding has been developed. This is currently being extended to study the potential applications of such liquids and suspensions in dynamic systems for mineral, coal and recycled waste separations.

Jan 1, 1993

Many aspects of best practice resource evaluation do not create value, but poor practice can certainly destroy value. Generally companies prefer to present how their good practice adds value and for this reason few publications exist on examples of how poor practice can destroy value. However in big and small companies there are many previous and current examples of poor practice destroying value. The incremental expenditure required to move from poor practice towards best practice can be looked upon as insurance against destroying shareholder value. Examples of how poor practice in geology has destroyed value are presented as well as the improvement model used by BHP Billiton to add value and insure against destroying value.

Jan 1, 2002

Gold mining commenced at Telfer in Western Australia in 1977. Ore mining was carried out by owner equipment and personnel with waste stripping by a contractor. Initial ore reserves were in predominantly high grade, geologically simple reef structures. A mining method was developed using dozers to selectively mine the ore bearing horizons with a minimum of dilution. As the mine has developed the simple, high grade ore reserves have been progressively replaced by more geologically complex, lower grade reserves. In turn, mining methods have evolved to extract this ore by the most appropriate methods. On-going attention to ore mining practices will ensure that project profitability and viable mine life are optimised.

Jan 1, 1986

Human resources (HR) practitioners use a general suite of tools that they adopt to suit their company needs and profile. This paper will cover the main areas of a selection and recruitment process from applying for a job, resumT writing, participating in an interview finalising the job offer. A holistic recruitment process has many facets to it. These processes can be quite sophisticated and technical but at the end of the day they are designed to identify talent. A recruitment process will generally include: ability testing (usually online);telephone interview;face to face interview;behaviourally based interviews;psychometric assessments;presentations;simulations (independent or team based); and assessment centres, etc. Understanding the basis of these tools will go a long way to prepare you for the job market, enhance your performance in a recruitment process and stand you out from the pack.

Jan 1, 2008

During the century past geologists have discovered an extraordinary range of mineral resources. It is somewhat surprising, in view of their success, to look back and find that geologists have been concerned through the entire time about the adequacy of resources to meet future needs. They continue to express concern. The basis of their concerns seems to rest as much in social issue as in evaluations of geology.Demand for mineral resources is driven by population and by per capita consumption. Both have grown steadily over the past century, and both continue to rise. In 1890 the global population was about 1.7 billion, people. It has now exceeded 5 billion and the growth rate is such that by the year 2000, the global population will be between 6~ and 7 billion. Demographic projections suggest the global population will approach 12 billion before a steady state is reached dnrino the centiirv ahead

Jan 1, 1990

A career in the mining industry is both challenging and rewarding but comes with some unique complications. Few other industries have such a far reaching effect on individualsÆ lifestyles. Furthermore, few people working within the resource sector could say their job has had no effect on their lifestyle. Mineral deposits in Australia seem to exist predominantly in remote locations like Telfer, Mount Isa and Olympic Dam. With this comes a choice for young professionals; one that is not easy to make, with either alternative often having its pitfalls. This remote nature usually requires professionals (especially graduates and juniors) to choose between a fly-in, fly-out location or relocation to a remote town with less facilities (and some may argue attractions) than their coastal cousins. The challenge for young professionals is to pursue a career that will satisfy their professional goals while developing and maintaining away of life that is emotionally fulfilling.

Jan 1, 2005

The aim of this paper is to broadly review the purposes of valuations and the methods used to calculate them. Examples are provided by coal and alluvial gold properties. Important factors are consistency, how to deal with uncertainty, and the selection of discount rates. The purposes of valuation are seen as: 1.  valuations for sale; within this category are sales to third parties, sales between partners, and vendor valuations for prospectuses; 2.  to provide bankable estimates for financing; and 3. to provide values for local body rating. The methods used depend on the purpose of the valuation and the amount of information to hand.

Jan 1, 1988

We live in a world in crisis. One where the tides of change run ever faster. Where the only thing we can be sure of is change itself. The challenge we face, therefore, is not how to resist the forces that move us nor even to try to predict where they will lead us, but to harness their energy and use their momentum to find new and innovative solutions to problems that can seem intractable. Indeed, crisis is often the catalyst which energises a business to change its technology and to form a partnership with a company which specialises in pioneering new technology.

Jan 1, 1993

The topic for my address is Sharemarket Floats - Issues for Expert Valuers. I've decided to focus on three areas where current practice in the preparation of prospectus valuation reports for resource companies might be improved. My central theme is that the valuer for a float should augment the usual assessments of the value of the company or its assets, with some input on the way the share market might value the company's shares when they are listed. I will then look at the valuer's role in relation to vendor consideration, last I will look at his role in providing investors with some input on the risk dimensions of the new company.

Jan 1, 1989

Refractory gold concentrates and their roasted products have been examined by mineralogical and chemical methods, and the distribution of gold in the tailings after leaching has been Investigated.

Jan 1, 1989