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To grow a mining company today is seen to be challenged by the reduced interest in resources companies by the financial markets, the complexity of native title and a somewhat depressed commodity cycle. However, the opportunity to grow production and sales in a mining company are as numerous as they have ever been. It is the challenge of growing significant shareholder value that is difficult. The distinction between growth in æcompany sizeÆ and growth in æshareholder valueÆ is an important distinction upon which some resource companies are now firmly focussed. The equity market/commodity market cycle can provide windows of opportunity to consolidate and expand a company for the benefit of shareholders. These benefits may not be reflected until more buoyant equity markets return but, as the cycle turns, as it surely will, those with the foresight to position themselves may be richly rewarded.

Jan 1, 2000

This paper sets out a number of means by which professionals can reduce or eliminate the risk of professional liability whether as directors, employees, partners, independent consultants or contractors. A relationship between client and professional is commonly cited as an example of a fiduciary relationship: the professional "undertakes or agrees to act for or on behalf of or in the interests of' the client "in the exercise of a power or discretion which will affect the interests of that other person in a legal or practical sense."2 As a fiduciary, a professional must ensure that his or her exercise of power does not result in a position of ascendancy or undue influence over the client. Also, a professional must avoid situations where there is scope for even the perception of potential conflict between his or her professional duty to the client and his or her own Interest.

Jan 1, 1995

EARLY HISTORYIt is 91 years since the epic discovery of gold at the eastern end of Kalgoorlie's main street appropriately named Hannan's Street after the prospector who found the first gold here on17 June, 1893.The Spirit that motivated the early prospectors in their search for gold in this thirsty sun-burned land, unmapped, uncompromising and difficult is characteristic of gold prospectors the world over. Conditions have changed since then substituting comparative comfort for previous austerity and privation, but the quest-ing spirit, the everlasting optimism, the perseverance in the face of frustration .and disappointment still exists.It exists with the prospector who more often than not is a company geologist; it exists with the shareholder enjoying through his investment a vicarious participation in this wonderful, exciting industry and not the least with those people who have chosen the goldmining industry as their career.

Jan 1, 1984

By Tonkin D. A

Poor performance in the several stages of the magnetite recovery circuit, coupled with poor desliming through inefficient and over- loaded desliming screens, led to excessive magnetite consumption. An accurate and reliable sampling programme was established covering all outlets of the plant. Emphasis was placed on frequency of increments in an endeavour to detect extreme conditions of short duration. Systematic checking of the entry points to these outlets than identified those sections of the recovery circuit at fault, namely magnetite recovery separators and the heavy media cyclone product rinsing screens. More product rinsing water was provided, and modifications to the rinsing screens improved the efficiency of these units. Consistency of operation through automatic control of level eliminated the sudden massive losses in the magnetic separators. Load on the recovery circuit was then reduced by improvements to the raw coal desliming screens. A 50 per cent reduction in magnetite consumption was achieved.

Jan 1, 1974

Knelson concentrators are commonly used to recover fine liberated gold in gold processing plants. The decision to employ a gravity gold circuit consisting of centrifugal devices such as Knelsons is primarily taken on the results of GRG tests, among other considerations. While the GRG test is considered a material characterisation test, which is useful in the design stages, its use in evaluating the performance of an existing unit is questionable. The problem is exacerbated by the fact that it is time consuming and costly. This paper examines the validity of the GRG test for performance evaluation and discusses alternative test work that can be performed to evaluate the performance characteristics of an operating machine. Principles that are useful in selecting optimal operating parameters, such as optimal fluidising water flow rate for a given ore/machine combination, are also discussed and illustrated with laboratory and plant data.

Jan 1, 2007

By Ruffles B. R

A computer simulation has been developed to model the flow of copper ore in Isa Mine. It simulates extraction of copper ore from the 1100 orebody by load-haul-dump (LHD) units to ore passes, haulage from chutes on 19 level by Rockflo trains to crusher bins, crushing and hoisting. It can assess in terms of the tonnage and head grade of ore hoisted, the effect of varying operating strategies, as well as measur- ing shortfalls in required capacities of any of the operations (extraction, hauling, crushing and hoisting). The simulation was designed as a modular, deterministic, steady-state model with parameter input allowing complete flexibility in its use. Queuing theory is used extensively to evaluate the effect of interference at potential bottlenecks. The model has been used to determine the effect on production of varying train sizes, maintenance policies on the haulage circuit, orepass capacities, and extraction operations.

Jan 1, 1974

By Gordon DM

SUMMARY Tyres account for 25-30% of the operating costs of large capacity haul units as used in open-cut mines. Tyre operating costs can be substanti- ally reduced and often contained in real terms by applying knowledge that is now available. This paper describes certain specific advances in tyre management, namely batching, bias adjustment, cumulative plotting and the so-called "pressure-temperature" system of tyre pressure control, originated on the Mt. Newman Mining Company's Newman minesite, and discusses the contribution that each has made to improving tyre management and reducing costs. INTRODUCTION Tyres are a significant cost in mining. Tyre costs make up between 25% and 30% of the operating costs of large (i.e. 100 tonne and larger capacity) open-cut mine haultrucks. On a large mine this tyre cost may amount to several millions of dollars each year. It is a fact that through careful

Jan 1, 1982

By B Shen

The Wambo Rail Spur located near Singleton, New South Wales, Australia, runs for approximately 14 km linking the Mt Thorley rail loop and the Wambo Coal Mine. The project involves a 260 m long tunnel in weathered sedimentary and intrusive materials. The tunnel has a low cover and runs under a main highway. This second paper on the project looks into one aspect of the tunnel in detail: the use of shotcrete arch as the primary support for part of the tunnel excavation. The use of shotcrete instead of steel arch, formulation of the material specification, construction sequencing, installation at the excavated face and material testing for verification related to this facet of the project will be discussed in this paper. The tunnel opened in April 2006, and two years on, we briefly reflect on the impact of this design decision on the overall project.

Jan 1, 2008

Coal mining safety and health legislation is more than typical of safety legislation which has been born of adversity. Indeed, in the main it has been the child of disaster. Requirements which now appear obvious were indeed only occasioned by either social injustice or more commonly by great disasters. Even then changes were often made only after months or years of deliberation by committees. Early mining legislation in New South Wales benefited from the experience in Great Britain. The pioneers of our industry were miners from there and brought with them the basic British legislation, so we started with knowledge gained the hard way. A review of accidents statistics provides a measure of the effectiveness of mine safety legislation, but unfortunately rules cannot control human nature. Miners, managers and inspectors must work as a team to make mines safe and new legislation in New South Wales is planned to this end.

Jan 1, 1975

In late 1984, Council of the Australasian Institute of Mining and Metallurgy accepted a proposal to establish a Mineral Heritage Committee. This was to be involved in matters relating to mineral heritage-its recording, its preservation, and the acknowledgement that it can be of use to the mineral industry in the future. The Committee was established to ensure that all of the disciplines of our profession were included and that, so far as possible, all of our country as well as those countries of the Southwest Pacific Basin were represented. Some work has been commenced to bring real- isation of the importance of the heritage of our mineral industry to the forefront of the commu- nity's interest. There is not a state in this country and the Southwest Pacific where the mineral industry has not at various times proved to be the basis of community development.

Jan 1, 1987

Exploration by Cyprus Minerals Australia Company (formerly Amoco Minerals) has successfully outlined significant Au-(Cu) mineralisation at Starra, 150 kilometres south-east of Mt. Isa. Mineralisation is stratabound and localized in deformed and metamorphosed ironstones (B.I.F?) and iron-oxide bearing schists of the mid-Proterozoic Staveley Formation. Over 90% of the presently outlined potential ore occurs in 4 discrete zones within a strike length of 3.5 kilometres. The inferred geological resource in these zones is approximately 6 million tonnes grading 5 grams per tonne gold and 2% copper. Roughly half of this is open-pittable, but more rigidly applied mining criteria will probably reduce the exploitable tonnage. Detailed infill drilling is in progress and a pre-feasibility study has commenced. The joint venture partners, Cyprus Minerals (75%) and Elders Resources (25%) expect to make a development decision by the end of this year.

Jan 1, 1986

The Coke Ovens Laboratory at Australian Iron & Steel, Port Kembla has been involved in the analysis of seam gases and mine airs for approximately twenty (20) years. This period has seen many developments and changes in the techniques used to the point when the current techniques are equal to other labora- tories involved in similar analyses. The laboratory has NATA registration for the analysis of mine airs and gases. Apart from routine testing of seam gases, ventilation airs and gases emmitted from coal bore cores a number of projects have been undertaken. These have served a twofold purpose, one to provide information to the customer, generally Collieries Research and Technology and secondly in developing the skills and capabilities of the Coke Ovens Laboratory. This paper discusses the development and services available at the Coke Ovens Laboratory for the analysis of gases and airs from collieries.

Jan 1, 1983

By Onton W

During the latter part of 1936, conditions encountered in sinking the Main Ore shaft made it impractical and uneconomical to continue deepening it to serve haulage levels below the present No. 5 level. Plans were therefore made for an interior shaft, to serve new lower levels, that terminated above No. 5 level so that ore hoisted could be drawn off on this level and transported to the Main Ore shaft for final conveyance to the mill crude ore bin. The No. 2 interior ore shaft was only developed below No. 4 level and borehole ropeways with a winder located on the surface were installed in preference to an underground winder installation. No. 2 ore shaft with borehole ropeways commenced lead ore hoisting operations in September 1938. Apart from the copper ore hoisted in the war years of 1943-46, lead ore was hoisted to No. 5 level until September, 1951.

Jan 1, 1988

By LaBrooy S. R

Crushing for the gold industry involves fine crushing and a degree of primary milling, and this presents new problems and challenges, partiuclarly on many of the new ore-bodies now being opened up. All of this calls for a better understanding of some of the basics of fine crushing and milling. Accordingly, in this paper the "typical" contemporary Australian gold mining operation is firstly delineated, in terms of representative ore types and typical crushing and milling tasks. Then some of the technical and economic basics related to fine crushing are re-examined, including: energy relationships in crushing and milling; concepts of reduction ratio; recirculating load controversies; and questions of realistic economics in crushing gold ores. The economics of the typical gold mining operation are shown to be rather marginal; not the lavish "bonanza" many may imagine. Likewise, crushing cost expectations are frequently quite Unrealistic.

Jan 1, 1987

George Fisher Mine, near Mount Isa in northwest Queensland, has been producing Pb-Zn-Ag ore since the late 1980s. It consists of two separate underground deposits, George Fisher South and George Fisher North. These two deposits are drilled and modelled separately but are crushed and hoisted as a single stream. The Pb-Zn concentrator in Mount Isa processes ore from George Fisher Mine and Black Star Open Cut, with production also from the Isa Lead Mine until January 2006. This paper outlines the steps involved in setting up a robust reconciliation system for George Fisher Mine, in conjunction with requirements of the Pb-Zn concentrator, Black Star Open Cut Mine and the Mount Isa Lead Mine. Good quality input data and commitment to training have contributed to establishing a robust and effective reconciliation system. Reconciliation data has highlighted several other continuous improvement opportunities.

Jan 1, 2006

By Hengst B

The first production stage in any mining operation is the breaking of whole rock into fragments small enough for loading and subseq- uent handling. This primary fragmentation is most frequently accomplished with blasting. The maximum fragment size and the fragment size distribution have an influence on the subsequent loading, handling and crushing costs. It is assumed that total rock fragmen- tation in practice is a result of an interact- ing array of radial cracks from various blastholes. The representation for the basic pattern of radial cracks emitted from a particular blasthole is first described. A model is then developed simulating the interaction between blastholes at various burdens and spacings, and in simultaneous and delayed modes. The resultant picture is analysed and a fragment size distribution calculated. Methods of incorporating the existing faults in the rock are also discussed. Finally application of this model to various facets of mining are considered.

Jan 1, 1977

By Coxhead B. A, Brandt B. A

The geological exploration and evaluation of coal reserves involves the appraisal of very large amounts of data. Computers afford an ideal means of handling and manipulating the data, thereby avoiding the laborious and expensive method of manually compiling the logs in full descriptive language. The Minad system of computer storage and retrieval of geological and analytical data is particularly suited to the description of cores and cuttings from exploration drill-holes. The encoded data is arranged in a 120-column computer output sheet format; descriptive geological information in a 54-column geolog and analytical information in a 64-column assaylog. The acquired data is quantitative, uniform and relatively complete and can be selectively retrieved for processing by a wide range of specialized computer programs developed for the coal mining industry. Visual retrieval of data for manual processing is facilitated by the use of simple codes and logical word abbreviations.

Jan 1, 1977

During the 1950's there was a flurry of activity on the design of main ventilation shafts for mines. More recently, a new ana- lysis was commissioned in relation to the multi-shaft, nuclear waste isolation facili- ties currently under design in the United States. This paper presents the major find- ings of that study and should prove of value as a reference in the design of proposed new shafts. An overview of mine shaft resistance introduces the effects of the shaft walls, fittings, conveyances and shaft stations. Each of these is analyzed in turn. A com- pletely new technique is described, which facilitates the estimation of wall resis- tance. The effect of size of a conveyance is quantified and shown to be dominant when the cage occupies more than 30 per cent of the shaft cross-section. The dynamic effects of a moving conveyance are also analyzed.

Jan 1, 1988

In the first half of 1987 two four metre diameter raise bore holes were drilled at the Olympic Dam Project for ventilation purposes. The first hole, 476 m x 4.0 m diameter was completed in 96 days, 35 days longer than scheduled. The second hole, 407 m x 4.0 m diameter was completed in 39 days, 2 days ahead of schedule. Both holes were drilled with a Robbins 121R rig using a Wirth head that consisted of 23 face cutters and 5 side cutters, supplied by a contractor. After the sites were located a grouting program was carried out to help seal off an aquifer between 160 and 180 m below the surface. Cavities discovered in the Andamooka Limestone were filled with concrete. Because of the overlying dune sands and clay both sites were pre-sunk to the competent Andamooka Limestone.

Jan 1, 1988

The purpose of this paper is to discuss briefly the problems encountered in designing and sinking No 7 shaft, and to present the methods employed in the operation.The illustrations accompanying the paper show the details of the construction of the equipment used in completing No 7 shaft, consequently the descriptions appearing in the text are brief outlines only. Mineral leases Nos 7 and 8, held by the Broken Hill South Limited, comprise an area of 69.5 acres. The length of the holding is approximately 2500 ft.The western orebodies, which are the main producing masses, enter the property at the northern bonndary. Generally, the dip of the orebody is to the west, and the pitch to the south, but local variations occur and even a reversal of pitch has been noticed. The angle of dip is approximately 70 degrees and the angle of pitch 45 degrees.

Jan 1, 1932