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By L. R. MURPHY

This paper gives a general description of mining operations at the Rosebery Mine and a brief account of the older Hercules Mine. The more unusual aspects of the operations, such as the sinking of the inclined shaft, blast-hole experiments, diamond drilling practice, and proposed future developments are described in detail.The following main heads are used:Roseberry- General production Data.General Description of Ore-body, and Characteristics of Ore and Country Rock.Layout of MineMining Methods, Filling, etc.Blast Hole Stoping.Sinking Main Inclined Shaft.Mining Timber. Contract System.Diamond Drilling and Sampling.Surveying.Labour Force.New Developments, Sand Filling and Pumping.Hercules-Situation of Mine.Transport-Haulage and Aerial.Ore Bodies.Stoping Methods.Ore Handling.

Jan 1, 1949

By M Olsen

"Segregation of conveyor roadways is a ventilation practice that is being increasingly applied in Australia. It is largely driven by the legislated requirements in Queensland pertaining to separation of escapeways from the mine. This legal requirement was based on a recommendation from the Moura No. 2 WardenÆs Inquiry (Windridge, 1996) into the mine disaster that claimed 11 lives. The report recommended: ... the introduction of a requirement for all underground mines to have one intake airway that is completely segregated from other parallel intake airways so as to provide two separate means of egress from the mine via an intake airway.This recommendation seeks to assist mine workers in escape from a mine after a fire by providing them with an airway that is free from smoke or contaminants.The concept of an airway being æcompletely segregatedÆ is an ideal that is challenging to implement in practice when considering the effect of leakage. The practice of belt segregation is concerned with the potential for fires in the belt roadway although there are numerous other potential fire sources in underground coal mines. A review of segregation practices has been conducted applying ventilation engineering principles. Four different scenarios have been analysed with regard to the effectiveness of the segregation stoppings in preventing potential fire contaminants migrating to other parts of the mine. The results show that in some cases the benefits of segregation to a person evacuating a mine in the event of a fire range from beneficial to detrimental. This is influenced by many factors including the location of that individual in that particular mine. There is room for improvement in the design and implementation of escapeways in underground coal mines. Escapeways need to be planned and designated with regard to the potential sources of fire, pressure differentials between escapeways and the operational practicalities of maintaining the pressure differential between them.CITATION:Olsen, M, 2013. Belt road segregation and escapeways - Compliance or risk management?, in Proceedings The Australian Mine Ventilation Conference, pp 311-318 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 1, 2013

A broker relies heavily on mineral valuations and independent experts' reports to provide the fundamental information, both technical and commercial, which provides the basis of estimating the sharemarket value of securities and underlying assets. It is important to appreciate the significant variance that can occur between the market value and other types of valuation at a particular point in time. In general, most experts' reports and valuations seek to provide estimates of technical/fundamental or ""fair"" value which correspond to the Corporations Law and accounting standards requirements. They do not usually attempt to estimate (stock) market values and it is usually and quite correctly the broker's task to estimate market values on the basis of a technical appraisal and consideration of all other commercial, market and financial influences. Therefore ideally, an independent experts' report or information memorandum will include material relating to commercial and management aspects of a company as well as detailed technical reviews and fundamental valuations. Wherever sensible cash flow projections can be made, cash flow-derived valuations, usually based on discounted cash flow (DCF) calculations, remain the preferred valuation methodology. Brokers in general would not argue with this preference. However, there is a paucity of examples of valuations where alternative methods are applied as a check on the reasonableness of a DCF-based estimate.

Jan 1, 1994

By BLAKE DAWSON WALDRON

I must acknowledge my strategic adviser, Mr Lance Grimstone, who contributed to the development of this paper, and collated the text and figures.

Jan 1, 1994

By T N. Little

This review paper presents an integrated and practical insight to blasting geology and its importance. This approach involves developing blasting objective up front and implementing geology specific blast designs. The author refers to this approach as ‘starting at both ends’. There are many human-imposed controls on blasting operations, such as: safety, security, legislative, company standards, heritage, and environmental constraints. Thus it is possible for some operators to lose sight of the controls imposed by nature. This paper demonstrates how site geology controls or influences many aspects of the rock breaking processes and how a focus on this aspect has potential to add considerable value to mining operations. It is obvious that mining companies concentrate their efforts on economic/ore geology (good rock geology). However it is the author’s experience that they also concentrate on engineering geology (bad rock geology) only when forced to do so by the ground conditions, but seem to run out of puff before they apply blasting geology (big rock geology). This paper contains five main sections. In the first section, the impact of geological controls on blasthole drilling is briefly discussed in terms of drill selection, penetration rates, bit wear, blasthole stability, blasthole deviation, and health precautions. In the second section the geological controls on aspects of geometric design are reviewed. These include: hazardous minerals, valuable minerals, selection of the blasting techniques, geological structures, blasting direction, and blasting geometry. Section three overlaps with the geometric design section and deals with aspects related to explosives. Topics addressed include selecting the explosive type based on geology, distribution of explosive charge in space and time, explosive performance, and the rock response to explosive loading. In the fourth section, examples are given of the operational complexity needed to implement a blast to cater for difficult bench geologies, environment constraints, past mining (voids) and need for a high degree of quality control. Section five demonstrates geological controls on blast results. Blasting results include the muck pile characteristics, downstream handling and processing, damage to the remaining rock, and blasting emissions.

Nov 8, 2011

By D J. Brake

Faced with the need to improve workplace conditions in both its development and production headings in its existing K1 orebody, as well as its new K Link and K2 orebodies, the Kencana mine in Indonesia took the novel approach of reversing the ventilation on most of its access ramp by outcasting up the ramp to the portal. Working levels were then fed with fresh air via auxiliary fans sealed into the current surface ‘egress’ intake raises (ladderways) or another small surface intake raisebore rather than from fans hung in the ramp as in the past. Outcasting the portal provided a substantial increase in the total mine exhaust capacity allowing fewer levels to be ventilated in series and significantly improving conditions, especially in the most difficult workplaces to ventilate. It also reduced the consequences if there was to be a fire on a vehicle in the ramp. The same system using the ramp as an exhaust is also intended to be used as part of the final ventilation solution for the new K2 orebody which also uses a novel single surface ventilation shaft that is vertically split into separate intake and exhaust compartments using a concrete brattice. Using the main ramp as an exhaust has potential application in many other operations in Australia using surface ramps which otherwise frequently suffer from overuse of series ventilation circuits and poor working conditions at the mine bottom.

Mar 21, 2011

By V Pfannenstiel

The United States (US) coal mining industry has been working under comprehensive planning, operating and rehabilitation regulatory requirements for nearly 35 years. The public desire for environmental protection during mining and rehabilitation following mining to achieve post-mining land use and sustainability goals has been a major factor and continues to influence the process. Mining companies have evolved operations to achieve outcomes that address the desired goals and regulatory requirements cost-effectively and successfully. Over the 35 year regulatory period, requirements for more diverse topography, specialised revegetation communities, landform stability and assured sustainability have increased and become more complex. These challenges are effectively met by maximising integration of mine planning and operating with the rehabilitation process. Rehabilitation is then implemented in a more timely and efficient manner and with effective results that achieve desired outcomes, commonly with added value. Peabody Energy (Peabody) has taken this approach in its US operations and this paper discusses an integrated approach and illustrates learnings and results with examples from several of its western US operations.CITATION:Pfannenstiel, V, 2012. Integrated planning, mining and rehabilitation for effective results and sustainable land use - A western United States perspective, in Proceedings Life-of-Mine 2012 , pp 219-232 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By C Tapia Cortez, C Sammut, S Saydam, J Coulton

‘Like every other commodity, the value of the metals is subject to variation’ (Ricardo, 1817). Mineral commodity price uncertainties have always been a significant issue in mining business due to the close relation between global economic conditions and commodity prices, which commonly generates significant and unexpected price fluctuations. Price forecasts have been driven by economic theory, which states that in the long-run market will be balanced and that prices tend to the marginal cost of production. However, this theory has been misunderstood in the mining industry and future prices through time, in real terms, are assumed to be unchanged. This is unrealistic due to regardless of the cycling nature of economy and the omission of uncertainties. Furthermore, using historical data in traditional price forecast approaches does not guarantee realistic predictions as past events will not necessarily be repeated at the same intervals and with the same intensity. Mining, finance and economic sectors have made significant research efforts to predict prices and control uncertainties through classic linear, Gaussian and probabilistic simulation approaches. However, by definition, uncertainties cannot be measured or accurately modelled. Uncertainties can be identified to measure and manage the associated risks; therefore, uncertainties in mining projects have been historically misinterpreted, erroneously measured and poorly controlled. It is widely known that supply and demand functions drive market prices. While technological development noticeably influences supply, demand is strongly driven by psychological factors, mainly related to customer preferences and lifestyle expectations. Thus, human behaviour is one, or if not, the most important variable to determine commodity prices in a competitive market. During the last decades, alternative methodologies have been used to study uncertainties in human, environmental and market behaviours. Chaos theory, fractals, artificial intelligence and econophysics have been widely and successfully used to investigate complex dynamic systems to address uncertainties over time in the fields of neurosciences, meteorology, aviation and market trading. The application of these techniques in the market suggests a more realistic approach to the business environment. Through the combination of the methodologies above a novel long-run price uncertainties simulation approach that emphasise the differences between risks and uncertainties is proposed in this paper. CITATION:Tapia Cortez, C, Saydam, S, Coulton, J and Sammut, C, 2015. Copper price uncertainties – chaos theory to manage risks in mining projects, in Proceedings Third International Future Mining Conference, pp 261–272 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

Bacterial leaching of sulfide minerals are fairly well established in heap, dump and in situ leaching and the primary bacterial treatment of refractory gold concentrate using CSTR have gained industrial prominence in recent years. Three cultures, a mesophile T ferrooxidans (DSM583), a moderate thermophile Sulfobacillus acidophilus (strain YTF1) and a extreme thermophile (Sulfolobus strain BC65) were used for the biooxidation (pre-treatment) of the Porgera gold-bearing pyrite concentrate under optimum O2 and CO2 enriched air (30 per cent O2 and ten per cent CO2) based on volume ratios. The positive effect of using oxygen and carbon dioxide enriched air for the biooxidation of gold-bearing pyrite mineral was clearly demonstrated where an increase in Fe release rate by a factor of 2.8, 1.8 and 1.5 for DSM583, YTF1 and Sulfolobus respectively were observed compared with the shake flask tests. The lag phase observed with the other test conditions such as in shake flask or with air decreased by about 80 per cent for all three cultures. The average observed dissolved oxygen concentrations in the pulp for these tests were 8.7, 5.8 and 5.0 mg/L for DSM583, YTF1 and Sulfolobus respectively, indicating that O2 was not limiting in these tests. The pulp redox potential was observed to increase with time for all tests coincident with the leaching rate and reaching a maximum of 663 mV, however the maximum value differs for each strain, with DSM583 exhibiting the highest followed by YTF1 and Sulfolobus. Biooxidation of pyrite under optimum gas enrichment at different pulp densities showed near total Iron extraction occurred for pulp densities of three, ten and 20 per cent (w/v). At high pulp densities, more so at 40 per cent than 30 per cent (w/v), the leaching rate decreased rapidly for tests with YTF1 and Sulfolobus. Monitoring of dissolved O2 shows that O2 demand increased with increasing pulp density and the average dissolved O2 concentration observed for YTF1 and Sulfolobus at 40 per cent solids concentration was 1.0 mg/L and below, suggesting limiting oxygen and carbon dioxide conditions for these two cultures. The decrease in leaching rate observed at high pulp densities (30 and 40 per cent) under optimum gas enrichment was accompanied by low metal dissolution and low redox potential values which was attributed to shear stress due to attrition of cells by high solids concentration, toxicity of metal ions especially Ag and Fe and the formation of precipitates and jarosites as confirmed from XRD analysis of leach residues hence impeding the leaching process. Limiting conditions due to high pulp density and viscosity were only observed for YTF1 and Sulfolobus. The subsequent cyanide leaching for precious metals from the pre-treated pyrite concentrate in all cases shows the extent of gold and silver recovery increased with the degree of pyrite oxidation and Au and Ag recoveries in excess of 80 per cent were achieved compared with only 18.1 per cent and 35.9 per cent for gold and silver respectively when treated by direct cyanide leaching on the original, untreated concentrate.

Jan 1, 2004

By R J. Romañach

The theory of sampling (TOS) is now followed in the development of near infrared (NIR) spectroscopic methods for the pharmaceutical industry. TOS has been the guiding light for a two-step approach for spectroscopic composite sampling available for the development of real-time analytical methods for particulate-based industrial processes. The two-step spectroscopic sample composite has been used in the development of process analytical technology (PAT), an important regulatory initiative to improve the quality of pharmaceutical products. The two-step sample composite approach overcomes the low sample volume analysed by PAT methods; one of the key limitations to PAT implementation in the industrial production of particulate-based materials.PAT methods need to be validated demonstrating their accuracy, precision, specificity and robustness. TOS provides a deeper understanding of these validation studies which involve discrete particulate material. The validation of PAT methods is now being performed considering both sampling and analytical errors, while practically all previous method validations only addressed the total analytical error (TAE) of these methods. This has been a crucial impediment for the field of chemometrics as well.PAT is a key element of continuous manufacturing (CM) processes, which are considered an emerging technology capable of increasing the flexibility, agility and robustness of pharmaceutical processes while reducing their costs. The outflow of the continuous process is a 1D lot, and variographic analysis has been shown to discern process variation from sampling and analytical errors in pharmaceutical CM processes. Thus, variographic analysis is a process improvement tool with significant potential for improving CM processes. The possibilities for improving pharmaceutical manufacturing are enormous.CITATION:Romañach, R J, 2017. Theory of Sampling – from missing link to key enabler for process analytical technology, in Proceedings Eighth World Conference on Sampling and Blending , pp 63–68 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

Just as geophysics, in the form of 3D seismic and wireline logging, plays a key role in petroleum reservoir management, so too will geophysics play an important role in mining of coal, metals, and minerals in the 21 st century. The commercial and social imperatives driving greater use of geophysics are reduced costs, increased revenues, and enhanced safety. In short, superior utilisation of capital and management of risks. In relatively undeformed sedimentary environments it is possible to adapt petroleum-style 3D reflection seismic to image mines. This has been demonstrated most impressively in the Witwatersrand. Anglo-American, for example, completed a $1 million 3D seismic survey at Western Deeps in order to site a new $300 million shaft with confidence. Likewise, 3D seismic has gained rapid acceptance at Australian coal mines in recent years. Encouraged by these successes, metalliferous mining companies are supporting research in Canada and Australia, as well as South Africa, to adapt 3D seismic for more highly structured, metamorphic terranes. Because the mining industry is far more diverse than the petroleum industry in terms of commodities and geological environments, 3D seismic is not always cost-effective. A plethora of other geophysical techniques can be applied, many of which are employed in mineral exploration. Mine applications of geophysics differ from traditional exploration applications in two main ways: time scales and length scales are shorter, and boreholes are more plentiful. Borehole geophysical techniques therefore play a more significant role, both for logging and imaging. Logging systems detail the variations of in situ physical properties down the borehole at scales measured in centimetres, while geophysical imaging techniques can map features located tens or even hundreds of metres from the sensors. While geologists tend to think of boreholes in terms of chips and core, geophysicists perceive them first and foremost as access paths for instruments. Borehole logging has been employed at iron and coal mines for decades, mainly to accurately define ore boundaries in delineation holes. In base metal mines, Outokumpu implemented logging widely for orebody delineation in percussion holes in the 1980s. The benefit was a direct cost-saving, arising from substitution of core drilling with percussion drilling plus borehole logging. The practice has since spread to other companies. INCO, for example, defines nickel boundaries in blast holes at Sudbury using conductivity logs. The benefits are in the form of reduced dilution and enhanced ore recovery, flowing from a more accurate mine model. Density, natural gamma radiation, magnetic susceptibility, and conductivity are the principal metalliferous mine logging parameters because they can be recorded in both dry and water-filled holes. Sonic velocity is the premier geotechnical logging parameter, given its sensitivity to rock strength, stress, porosity, and degree of fracturing. Sonic is recorded routinely in exploration and geotechnical holes at coal mines. With the advent of slimline dipmeter, full waveform sonic, and optical and acoustic scanner tools, the role of borehole logging in geotechnical evaluations is expanding. Monitoring of strain and micro-seismic activity enhances safety during mine production. While qualitative interpretation of logs is adequate for stratigraphic identification or definition of boundaries, a wealth of quantitative information, eg density, can be derived from properly calibrated, repeatable geophysical logs. Moreover, geophysical logs can sometimes serve as surrogates for geochemical assays, and not only for magnetite and uranium. At OutokumpuÆs Kemi chromite mine, for example, gamma-gamma logging provides the basis for grade control. By reducing reliance on assaying, three benefits can be realised: reduced reliance on core drilling; lower core handling and assaying costs; and shorter turn-around times. Conventional downhole EM and borehole magnetics are used for near-mine exploration, and for ground sterilisation. Inco has enjoyed considerable success with borehole UTEM in the Sudbury Basin, for example, and Geopeko has applied three-component borehole magnetics successfully in the Tennant Creek area. Electrical techniques such as applied potential and magnetometric resistivity (MMR) are also finding application at mines. For higher resolution, borehole seismic, radio imaging, and radar have been invoked, with varying degrees of success, to delineate orebodies and map structures, or to geotechnically characterise the rock mass and identify hazards. Success mapping nickel sulphide shoots with borehole radar has been reported by WMC at Kambalda. There are no universal geophysical panaceas, and each mine imposes different geological, logistical, and economic constraints. Geophysics will not always be cost-effective. However, the greatest single impediment to expanded use of geophysics at mines has been the low level of awareness of geophysics on the part of most mine geologists, engineers, and managers and, equally, the limited understanding of mine geology and engineering exhibited by the majority of geophysicists. This myopia will be remembered as a 20th century affliction! Blue Sky areas for mine geophysics in the next ten years include integration of geophysical data acquisition with drilling, enhanced grade estimation and rock mass characterisation, and the incorporation of geophysical information into mine models using geostatistical techniques. All these advances will be predicated on an expansion of petrophysical knowledge.

Jan 1, 2000

Exploration for uranium in Australia has so far discovered reserves equal to 17.5% of the Western World's. The Australian uranium industry, when fully developed, will be one of the largest producers and possibly the largest exporter in the world. The world's nuclear industry is young, rapidly developing in size and technology and is subject to more social, political and regulatory controls than any other industry. This paper considers the probable development of Australia's uranium industry against a background of normal commercial parameters together with other factors which are peculiar to the nuclear industry. As the theme of this conference is "Australia's role in the World Mineral Indus- try" this paper concentrates on the commercial and practical aspects associated with the development of Australia's uranium resources in a world context.

Jan 1, 1979

In 1955 the annual production of steel at Australian Iron and Steel Pty. Ltd., Port Kembla was 1.2 million tonne and over the following two decades this had progressively increased to the present capacity of 5.4 million tonne per annum. This increase in productivity has also been accompanied by important developments in steelmaking technology and these are explained in the chronological order in which they have taken place. Reference is made to the use of oxygen in open hearth furnaces, the B.O.S. process, the Argon-Oxygen decarburisation process for stainless steel, vacuum degassing and continuous casting. When the vacuum degassing and continuous casting units are commissioned, the Port Kembla Works will have achieved a standard of steelmaking technology equal to any in the world.

Jan 1, 1976

Pan Australian Mining lid installed a milling and gold leaching plant designed to process 2 million tonnes per annum of breccia sulphide ore. This plant was commissioned in January 1989. Since commissioning, increased ore reserves have been established and the plant has been expanded by the addition of one ball mill and several tanks to increase the design capacity to 3 million tonnes per annum. This additional plant was commissioned in May 1990, bringing the total number of mills up to three, each 4.5 m diameter x 7 m long. The paper details how milling rates have been increased at the expense of grind size to increase the capacity of the original plant from 2 million to 3.1 million tonne per year rate before the additional ball mill was Commissioned.

Jan 1, 1991

By Tran T

The kinetics of cementation of silver chloro-complexes from sodium chloride solutions onto copper and zinc was studied using rotating disc electrode system. The activation energies were found to be 10.8 and 30.5 k7/mole, in a 3M NaCl solution on copper and zinc discs, respectively. Higher dissolution factors were obtained on zinc disc, due to hydrogen evolution, whereas, copper dissolved close to the predicted values. Scanning electron microscope studies were conducted both on copper and zinc- cdiscs-to evaluate the deposit morphology and its effect on reaction kinetics. Two stage deposit growth was observed both on copper and zinc discs. Smooth, coherent initial deposit followed by tree-like secondary dendrites formed on copper, whereas, scattered bulbous initial deposit followed by porous dendrites was typical on zinc disc.

Jan 1, 1992

By Lu S, Zhou S

The flash smelting technology employed in Jinchuan demands a better mineral processing concentrate with an MgO content below 6.5 per cent. Two ways for MgO removal have been investigated in detail based on properties and process mineralogical characteristics of the rich ores in the number one mining area in Jinchuan. The key to the first way is the use of a new flowsheet which has two-stage grinding and separation followed by single-stage regrinding and multi-stage cleaning for the rougher concentrate. The second approach utilises two novel reagents, AT-131 and AT-202, which have been developed recently. Excellent metallurgical performance has been obtained in a commercial test and a batch test, respectively. The MgO content of flotation concentrate can be reduced to about six per cent.

Jan 1, 1996

By Thornber MR, Davidson LR

The cause of spontaneous combustion of pyritic black shale has been studied by calorimetry and other techniques. The conditions required for ignition to occur are: 1. A critical mass of pyritic black shale. 2. Acidity. 3. Fine shale particle size. 4. A high ambient temperature. 5. The exclusion of air during the preparation of a calorimeter charge. The reaction is characterised by an initial incubation period during which an unknown phase is produced. The build up and oxidation of this phase results in a chain reaction culminating in ignition. The mechanism is believed to involve the interaction of pyrite, sulphuric acid, ferrous sulphate, or meta-stable oxysulphates, with ammonium nitrate. The recommended strategy for prevention of premature detonation is to neutralise the acids in the shale with quick and slow release alkaline materials.

Jan 1, 1986

Good morning ladies and gentlemen. It gives me great pleasure to talk to you today about a pet subject of mine, on when to mill and when to leach gold ores. According to Gold Fields Mineral Services of London, gold production in the United States in 1989 amounted to about 8.5 million ounces (259t), an increase of 29 per cent over 1988 and 67 per cent over 1987. The U. S. Bureau of Mines reports that from the major producing states of Nevada, California, Montana, and Alaska, some3.2million ounces of the 1989 production were produced from milling gold ores and 2.3 million ounces from heap or dump leaching. Ap- proximately 45 million tons of ore were milled and 140 million tons of ore were heap or dump leached.

Jan 1, 1991

A wide variety of process streams are sampled for grade control in the mining industry. However, in many instances the overall precision of the resultant analyses is inadequate for the intended purpose, ie grade control and optimisation of resource utilisation. Consequently, special attention needs to be given to the sampling, sample preparation and analysis procedures in place to ensure that meaningful grade control decisions can be made based on the analyses generated. For example, it is virtually impossible to control a process to within, say, ¦0.2 per cent if the overall precision of the analyses is no better than 0.5 per cent. Hence, precision targets appropriate for the task need to be established and the overall precision achieved in practice monitored and controlled on an ongoing basis.

Jan 1, 2008

By Balks AI

Systematic roof bolting in Australian coal mines began at Elrington Colliery in 19)49. Since that time the proportion of the roof supported by roof bolts has increased until, in 1970, 1.5 million were installed in Australian coal mines. This rapid growth of roof bolting has meant that the range and variety of roof bolting machines has altered also. The-number of machines now available both to bore holes and place roof bolts has increased. to the point where both rotary and per- cussive machines are used extensively. Generally, until the last four years, roof bolting machinery in Australia followed the practices in vogue in the United States. However, in -recent time the particular problems of Australian coal mining have necessitated the development of equipment primarily suitable to Australian conditions.

Jan 1, 1971