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By Schoning W. L

Ore deposit models form the basis for numerous other economic decisions in the mining process. The success of these economic decisions therefore depend directly on the accuracy of the ore evaluation process. The Geology Department at the Sishen Iron Ore Mine is responsible for the generation of a reliable geological computer model of the rock material with predicted grades. This information is then utilised for further ore reserve calculations, mine planning, production scheduling and grade control. Owing to a very complex geological orebody, grades and beneficiation characteristics differ significantly from sample to sample. This means that ore evaluation is a difficult process and great reliance is placed on computer techniques. In 1993, preparation for the ISO 9002 quality certification of the mine motivated the Geology Department to hold formal `problem solving' sessions in order to identify and revise problem areas in operating

Jan 1, 1995

By Forster I, Thilo A, Dean AK

A prototype production tool capable of operation in the hole sizes (

Jan 1, 1988

By Napier-Munn T. J, Morrison R. D, Moloney M. J, Corrans I. J

A dynamic simulator for CIP / CIL gold recovery plants has been developed at the Julius Kruttschnitt Mineral Research Centre within a collaborative, industrially - funded AMIRA project and with the participation of the Western Australian School of Mines. The simulator incorporates kinetic models for the leaching of gold from ore and its adsorption onto activated carbon, and the residence time distributions of the leach liquor, pulp solids and carbon in the circuit. Features of the simulator include the effects of gold loading distributions on both the ore and carbon on reaction rates, and the difference in residence time distribution between the leach liquor and pulp solids. The simulator allows for the estimation of kinetic model parameters from full scale applications, as well as some scale - up of parameters from laboratory batch tests. The laboratory tests were conducted at the WASM as part of the collaborative research project. The simulator can operate in both steady - state and dynamic modes, and has potential applications in design, optimisation and control of CIP / CIL plants.

Jan 1, 1991

By Fourney W. L, Dick R. D

Tests were conducted in plexiglass and Rockite models to determine if crater blasting could be improved by changes in charge geometry or by alterations to the borehole. Circumferential grooves were placed at various locations in the borehole in an attempt to control the initiation site of the crater. Grooves located at or above the top of the cylindrical charge had no effect on the resulting crater. Grooves placed too low in the borehole were successful in controlling the initiation site but the growth of the fracture system was not sufficient to reach the upper surface. Grooves located at a height of two thirds of the charge length were quite successful in that resulting craters were bigger by at least a factor of six than the normal crater. Testing was conducted in Rockite models to investigate charge geometry. Spherical charges in ungrooved boreholes resulted in crater sizes that were three times larger than those caused by cylindrical charges.

Jan 1, 1990

By Evans R, McCallum P

Modem blast initiation systems allow users many options for connection and application in the field, and have resulted in more innovative and complex uses of sequencing to influence blast outcomes. However, no tool existed which allowed the blaster to easily and quickly assess the effect of different options. The original requirement was for a computer program which allowed the easy input of blast patterns and the associated initiation sequence, and then permitted the evaluation of different options with respect to established criteria such as the number of holes per delay and angle of initiation. The implementation of this goal saw the development of the SHOTPIan blast sequence design software, with particular emphasis on an easy-to-use menu driven interface and visualisation of the blast sequence. Extensive trialling during development saw the incorporation of additional features requested by industry such as the ability to import from established mine design software packages, and further features such as the calculation of burden relief times. Case studies of the use of the program are provided, where the rapid evaluation of a number of options has enabled blast results to be optimised. Examples are also given of cases involving two-path initiation

Jan 1, 1995

By Mendeckl A. J

Anglo American Corporation has always viewed technological development as vital and as such has placed research and the implementation of new technological practices high on its priority list. Support is given to a number of research institutes but a significant degree of reliance is placed on in-house research carried out at individual companies and at the Group's main laboratory complexes. The Corporation's interests are diverse with advanced practices and innovative technology ranging from new battery technology with wide application to deep level shaft technology with very specific application. In this paper, we aim to concentrate on a particular system developed primarily for use in seismically active deep mines. The system has proved to have far wider application and has the potential to be further enhanced to meet the needs of users across a broad range within the industry and even beyond. As the nature of this conference is to inform delegates of advanced mining practices, we should simply mention that we could have talked on subjects relating to the advances made in deep level winding technology including winder drive and brake control to alleviate dynamic rope loads, shaft steel design for high pay load high speed winding and shaft safety systems such as slack rope devices and moving lip loading facilities to cater for rope stretch. Other areas of interest relating to refrigeration using ice technology or non-explosive rock cutting using diamond wire or saw technology could also have been of interest. As the South African gold mines become deeper and the problems associated with depth become more acute, answers had to be found and systems developed to cope with very high rock stress and the related seismicity. The fundamental understanding of the behaviour of the rock mass has always been important but became critical on our mines to ensure the safe extraction of the orebody. Basic research into and the application of physics, applied mathematics, seismology, rock mechanics, electronics and computer technology have helped us to develop the Integrated Seismic System - Integrated because of the system's abilty to monitor seismic and non-seismic sensors simultaneously and because it encompasses data acquisition, processing and interpretation into one system. The system which is in use at all our gold mines has found application not only in South Africa but also in such locations as Australia, Chile, Canada, Europe and Japan. A highly motivated team of scientists under the leadership of Aleksander Mendecki developed the majority of the hardware and software needed for the system. In essence, the system allows us real time monitoring of energy release and stress transfer data that with the aid of modern computers is turned into useful information. The information so obtained has allowed us to improve our mine and extraction designs to minimise the inherent hazards. The system has proved to be an extremely useful management tool as substantiated by the demand for the product. The paper is intended to convey to the reader the technical concepts and the presentation is intended to demonstrate the usefulness of the system.

Jan 1, 1995

I feel a little like the Parson delivering his Sunday Sermon, chastizing his parishioners for not coming to Church. Those who need to hear me are absent.Nevertheless, I hope that if you agree with what I am about to say you will go forth and spread the word.We often hear of the impact mining has on the community. I prefer tonight to deal with the impact some community attitudes have on mining, and I want to point out that the results of these attitudes rebound to the detriment of our society. I want to deal particularly with regulation, taxation, and proflts.In a civilization whose standard of living is essentially dependent on an adequate and reliable supply of cheap metals and fuels, it should be evident to Blind Freddie that mining must be encouraged.I must express concern at the constraints inflicted on the mining industry by our community. We tend to blame Government for our difficulties, but we must recognize that Government acts merely as agent for the community. It is fair to say that in a free society, if Government actions do not reflect the demands of the electorate, then it doesn't stay the Government. It is important though for Government, in framing its policies, to ensure that it is not unduly influenced by the loud voices of minority groups.The people of our nation have every right to demand that our industry meet certain criteria to be allowed to operate. We all wish to live in a healthy and congenial environment, and to have our individual comforts protected. It is essential, however, that the community realizes that its demands on the mining industry are affecting Australia's prosperity.Each new regulation and each new tax or impost has its effect on investment, employment, and national revenue. Restraints result in an increase in costs which in turn raises the minimum value of a mineral deposit which is economically mineable. It results in minerals, which could be mined under more favourable circumstances, remaining in the ground, perhaps lost for ever.

Jan 1, 1978

By Moy A. D

The Esperanza deposit is located 120 kin N of Mount Isa, Queensland at approximately lat 19¦20'S, long 139¦22'E on the Camooweal (SE 54-13) 1:250 000 scale map sheet. It is one of several structurally controlled copper ¦ cobalt deposits developed along the Mount Gordon Fault zone and related faults, within the Western Fold Belt of the Mount Isa Inlier (Figure 1). Together with the nearby Mammoth orebodies it forms the basis of the Gunpowder operation of Aberfoyle Limited. Until recently ore was mined from the Mammoth orebodies by open stoping with decline haulage to surface leach pads. Leaching of in situ broken ore (in place) and surface heaps, followed by solvent extraction and electro-winning (SX-EW), produced copper metal on-site. In March 1997, mining was suspended at Mammoth and the focus of the Gunpowder operation switched to development of the Esperanza orebody, which is expected to begin open cut production in mid 1998. SX-EW methods will produce 44 000 tpa of copper from an expanded plant. The pre-mining mineral resource at Esperanza (measured, indicated and inferred) is estimated at 4.6 Mt averaging 7.7 per cent copper.

Jan 1, 1997

In the past ten years or so there has been a renewed interest worldwide in the processing of refractory gold ores. The Archean province of Western Australia contains both numerous and major gold deposits, and has a long history in the development and practise of treating refractory ores (eg Blaskett and Woodcock, 1953). Depletion of shallow oxidised ores in recent years has re-focused attention on deeper sulphidic ores, and as a consequence has renewed interest in treatment methods for those ores which are refractory. Mineralogical factors he at the heart of reasons as to why these ores are refractory, and are the key to designing and improving treatment options in the longer term. This paper presents an overview of mineralogical factors that are relevant to the processing of refractory gold ores in the Archean of Western Australia. It is based on a number of research projects and other work on a variety of gold deposits, mainly in the Eastern Goldfields region, carried out over the past five years or so.

Jan 1, 1991

By C Torrisi, J Andreatidis, M Duffy

BHPÆs Cannington process plant was commissioned in October 1997. The Cannington ore contains high grades of silver, lead and zinc but also contains high levels of fluorine which must be removed to produce a marketable concentrate. As a consequence the plant is more complex than the typical base metal concentrator. Some of the features of the Cannington operation include a single stage autogenous mill, multiple stages of flotation cleaning, two leach circuits, pressure filtration and a paste fill plant. The start-up and achievement of design performance for new lead/zinc operations has traditionally taken much longer than for gold or copper operation and is littered with many tales of woe with feasibility targets often not achieved (Agarwal, Brown and Katrak, 1984; Bulatovic and Wyslouzil, 1999; Leung, Andreatidis, Woodall and Alford, 1996; Sherman, 1999; Ward, 1998).

Jan 1, 2000

By Gonzalez JM

The Pao gold prospect in N. Luzon, is an example of a high sulphidation epithermal gold system hosted in Mid-Tertiary alkaline volcanics, in the Philippine Arc. Styles of mineralization include: quartz-enargite veins, vuggy silica alteration bodies, and pervasive low grade (0.5ppm) gold mineralization, associated with kaolinite-pyrite-quartz alteration, and geochemically characterized by high As and Hg. Early magnetite-epidote-chlorite alteration linked to an unexposed granitoid is overprinted by an extensive zone of advanced argillic alteration (kaolinite-pyrite-quartz). No alunite is recorded. Important controls of mineralization include; a broad anticline intersected by axial faults, permeable pyroclastic units, and upward confinement of the alteration system by a highly impermeable, clay-rich volcanic unit. At this stratigraphic position the most important mineralization waz developed. The Pao high sulphidation system is not closely related to a stratovolcanic centre, and has formed subsequent to deformation of the volcanic field. It may, however, be related to an unexposed comagmatic intrusion.

Jan 1, 1990

Comparison of the Zadra, Anglo-American and organic solvent procedures for desorption of gold from activated carbon loaded in carbon-in-pulp gold circuits indicates that the Anglo American and the organic solvent procedures are considerably more effective than the commonly used Zadra procedure. Organic solvent elution procedures, particularly those using acetonitrile and acetone, can provide effective gold elution and very high concentrations of gold in eluate solutions. The operational simplicity and effectiveness of the Anglo American procedure would appear to make it the most satisfactory procedure available at the present time but this may change as the solvent elution procedures become better developed. INTRODUCTION The carbon-in-pulp technique has been introduced into the gold processing industry to by-pass the often lengthy CCD and filtration steps required in the conventional Merrill Crowe cyanidation procedure for gold recovery. Adsorption of gold on to carbon is also a valuable technique for recovering trace amounts of gold from low level waste streams from conventional processing procedures.

Jan 1, 1982

Coal mining in the Bulli seam in the Southern Coalfield in New South Wales has experienced the dangers of outbursts of coal and gas. These incidents present a major risk to the safety of mine workers and consequently a threat to the overall viability of the mining operations. Since the occurrence of a major outburst incident in the South Bulli Colliery in 1991 involving three fatalities, the primary contributory factors associated with coal/gas outbursts in the Bulli coal seam have been identified and a strategy for the management of the outburst risk has been formulated by the cooperation of mine operators, mine workers and the Department of Mineral Resources. Utilisation of risk management techniques in combination with modern gas drainage technologies and geological control methods have led to the formation of this effective outburst management plan. Clause 15 of the Coal Mines (Underground) Regulation 1999 in NSW has made it mandatory in an area of outburst to carry out mining in accordance with a code or guidelines developed for mining in outburst prone areas (DMR, 1999). In this paper an outburst management system is discussed which was developed for collieries in the Southern Coalfield that brings together all the available information including past experiences and risk management techniques in a documented form in order to maximise safety of mine workers. It is concluded that since the introduction of the outburst risk management systems in the Southern Coalfield in 1994 considerable reduction in outburst incidences have been experienced.

Jan 1, 2003

By Shugen T

Due to the increase of passenger traffic, a new station is proposed which is about 6.8km from south station. An underground connection line is under feasibility study for connecting these two stations in order to avoid the in- terference with surface traffic. In this paper the traffic condi- tion and the geological formation along the planned route will be described and analysed. Different methods of con struction have been proposed and dis- cussed such as shield method, slurry wall method etc. In this paper compari- sons are made among these methods and advantages and disadvantages given. The authors proposal to construct this connection line by NATM raise wide

Jan 1, 1987

In 1874 a stockman, JE Wright of Foxlow Station, recognised copper mineralisation when he was about 12 kilometres south of the station. The find was on the banks of the Molonglo River. Several small mines were soon operating along the ridge above the river, and the village of Captain's Flat was established.One mining company established in the 1880s was Lake George Mines. It's name was to remain synonomous with the name of the town until mining and treatment ceased on 11 March 1962.

Jan 1, 1993

By Katom M

Each of the two 32 feet diameter Semi Autogeneous Grinding (SAG) mills at Ok Tedi's copper and gold concentrator was treating at best 1500 tph at about 65 per cent mill availability in 1988. The process was effectively unmeasured and used manu

Jan 1, 1997

By Borshoff J, Von Pechmann E

The uranium mineralization in the White's East area of The Embayment is hosted by Lower Proterozoic schists of the Masson Formation which have undergone polyphase de- formation and upper greenschist metamorphism. Significant mineralization is also present in apatite rocks. The ore zones occur near an unconformity with overlying Middle Proterozoic sandstone and breccia conglomerate. Kink breccias and fracture systems related to post Middle Proterozoic reverse faults are the con- trols for mineralizing fluid migration. Pitchblende is the main uranium mineral and it occurs as fine disseminated grains, fibrous webs, clusters composed of botryoidal aggregates and locally as veins. Two genera- tions of uranium mineralization are present. The first generation (pitchblende I) occurs as fine grained inclusions within chlorite II, and the second (pitchblende II) as hydraulic fracture networks and massive veins intimately associated with sericite-hematite-chlorite III. Two hydrothermal alteration phases have affected both Lower Proterozoic and Middle Proterozoic sequences. The most extensive alteration mineral is chlorite, of which a number of varieties has been identified. Mg-rich chlorites are generally associated with the first phase alteration assemblages and are commonly replaced by hematite, seri- cite and Mg-Fe chlorites in massive pitch- blende zones. Other alteration minerals in- clude tourmaline, apatite, talc, quartz, magnesite, graphite, pyrite and rutile.

Jan 1, 1984

By N J. Arunakumaren

A coal mine is proposed for an area where a major river traverses the project area. There were initial concerns that inflow of groundwater from exposures of high permeability alluvium associated with the river system could pose mine dewatering problems together with adverse impacts on surface water resources in the river. The project included collation and analysis of geological and hydrogeological data collected historically over a long period of project investigation and evaluation. The project also included establishment of additional groundwater monitoring points to provide a reliable groundwater contours. The groundwater level contours were produced to allow numerical models to be calibrated to support estimation of groundwater inflow. River bed cross sections were also prepared to assist study of the effect of river flow on the inflow. Two separate MODFLOW groundwater models were produced to simulate long-term groundwater inflow to the mine with an upper model consisting of the Quaternary and Tertiary alluvium lumped together and a lower, separate model consisting of Mesozoic coal measures. Analytical solutions were used to predict initial inflow from the alluvium and from the coal measures.

Jan 1, 2003

By B Huls, B E. Smith, I Brake, M Yu

A brief outline of some of the pioneering events in the development of flotation technology, which originated in Broken Hill at the start of the 1900s, is presented. The development of the original Potter-Delprat process, the introduction of oils to generate froth flotation and the achievement of selective flotation processing are described, all focussed on solving challenges with the Broken Hill Pb-Ag-Zn ores. Some recent initiatives in flotation at BHP Billiton operations are also outlined, covering coal, copper, lead-silver-zinc and diamonds. Some views are offered on the characteristics of innovation in flotation and on possible trends into the future.

Jan 1, 2005

This paper outlines some of the recent developments in Spiral Concentrator design, with particular reference to the range of Reichert spirals supplied by Mineral Deposits Limited, typical applications, and test or operating data, are also provided for the different series of spirals now available.

Jan 1, 1978