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By F F. Pitard

The comparison between J Visman and C O Ingamells’ works with P M Gy’s works has been the object of intense debates in the past. Such negative debates inevitably resulted in a loss of many good opportunities. The author’s long experience in applying works of these three authors led to the pragmatic conclusion that it is relatively easy to integrate everything Visman and Ingamells created into the Theory of Sampling; therefore, it is suggested that the compatibility has been vastly overlooked, and a correction for such anomaly is recommended. It is important to emphasise that Visman and Ingamells works may be beneficial and provide relevant, harmonious additions in some areas, and ultimately offer attractive possibilities to sampling practitioners. Such additions may enhance our capabilities to predict sampling difficulties by using a stronger strategy and to design better sampling experiments that would allow us to further understand the heterogeneity of minor constituents, and especially trace constituents. Basically, the suggested integration is essential for sampling trace constituents in the environment, in food, in chemicals and in the pharmaceutical industries.CITATION:Pitard, F F, 2017. Integration of Visman and Ingamells’ works into the Theory of Sampling – a necessity to expand possibilities in sampling practices, in Proceedings Eighth World Conference on Sampling and Blending , pp 55–62 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

Flow Sheet Development of Three Geographically Distinct Chromium-Bearing Ores

Sep 13, 2010

By J W. Hedenquist

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Epithermal deposits (Au or Ag dominant, ± base metals) form within ~1 km of the surface in volcanic belts, both arcs and rifts, with the different tectonic settings reflected in distinctly different characteristics. Within arcs, deposits are typically intrusion centred and commonly associated with hypogene advanced argillic alteration, both in lithocaps and as halos to shallow or proximal portions of some veins; such alteration is coupled with processes that form porphyry Cu-Au deposits at depths of ~1–3 km. Introduction of metals is related to the subsequent phyllic-stage overprint; if this fluid rises to the level of the lithocap or into epithermal veins, Au mineralisation with Cu or Ag may occur, associated with sulfate minerals or muscovite. By contrast, Au-rich (both low Ag:Au ratio and bonanza grade) colloform quartz veins form at shallow depths in volcanic rifts, typically within a few hundred metres of the surface, with clay halos and topped by silica sinter if the palaeosurface is preserved. The geologic variability in volcanic belts, including host rocks, structures and hydraulic gradients, means that many epithermal deposits vary from the end-member features of the principal styles. Effective exploration requires familiarity with end-member styles as well as potential variations, plus the mineralogical indicators of palaeotemperature (eg evidence for erosion depth, fluid flow channels). This knowledge helps the geologist in the field to imagine what might be buried and where, and how to best test the target with drilling.CITATION:Hedenquist, J W, 2015. Recent developments in understanding of and exploration for epithermal deposits in volcanic arcs , in Proceedings PACRIM 2015 Congress, pp 11–16 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

The Macraes Mining Company Limited was listed on the New Zealand and Australian stock exchanges in January 1990, and the proceeds of the float were used to purchase a 70 per cent interest in the Macraes Gold Project, previously owned by BHP Gold Mines (NZ) Limited. Macraes Mining has had a 30 per cent interest in the project since May 1984, when it was incorporated. Project financing in the way of a gold loan was secured in February 1990 and construction commenced shortly afterwards. The mine construction activities were completed within nine months and the mine commenced operations in October 1990.

Jan 1, 1991

By L Spencer, H Zwingmann, I Graham, D Cendon, B Kelly, D Burkett, F Lau, P Lennox

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Kulumadau deposit represents an intermediate-sulfidation epithermal gold deposit (3.8 Mt at 2.3 g/t, Ag:Au = 1). Mineralisation is primarily confined to hydrothermal breccias within pre-existing fault zones, where it is disseminated throughout a hydrothermal matrix comprising chlorite-quartz-adularia-illite-I/S clays-calcite-pyrite. The host sequence represents numerous mid-Miocene pyroclastic flow eruptions within a tectonically active emergent shallow marine to subaerial depositional setting. Subsequent growth faulting was responsible for debris avalanches, which were subsequently cut by reverse faults. Faults were exploited by hydrothermal fluids, with the heightened porosity at the juncture between faults and debris material facilitating boiling of the ore constituents. Fluid inclusion studies suggest that fluid mixing between meteoric fluids and magmatic fluids, accompanied by boiling, were the primary mechanisms for gold deposition. The occurrence of anhydrite/gypsum as late-stage veins and their sulfur and oxygen isotopic values indicate post-mineralisation mixing of sea water with hydrothermal fluids.CITATION:Burkett, D, Graham, I, Spencer, L, Lennox, P, Cohen, D, Zwingmann, H, Lau, F, Kelly, B and Cendon, D, 2015. The Kulumadau epithermal breccia-hosted gold deposit, Woodlark Island, Papua New Guinea, in Proceedings PACRIM 2015 Congress, pp 205–212 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By V P. Elpatyevskaya, V S. Arzhanova

Main geochemical problems concerning the environment and mining industry interrelation are connected with the transformation of natural water chemistry by mining wastes. The investigation of many mines in Primorye, the southern part of the Russian Far East, showed that their mining waters have high concentrations of heavy metals and aluminium. Water acidity is primarily connected with the amount of acid-forming sulphide minerals in ores and also depends on the neutralising capacity of rocks. Considerable quantity of metals occur in the waters in dissolved form. Metal concentrations in mining waters exceeds the natural levels by two to five orders of magnitude and can't be reduced to the background levels even after multiple dilution. It is necessary to develop and put into practice new technologies so that to reduce the geochemical impact upon the environment.

Jan 1, 1995

Study on Treatment of Wastewater Containing Heavy Metal Ions Using Modified Oceanic Cobalt-Rich Crusts

Sep 13, 2010

By D S. Clarke, K B. Sporli

The Thames Goldfi.eld has been a major gold resource in the west of the Coromandel Peninsula, New Zealand, with the Waiotahi quartz vein system forming a large part of the field. Mineralisation is hosted by hydrothermally altered Miocene andesitic volcanic rocks. Both massive columnar-jointed and fragmental volcanic rocks are present. The vein system is dominated by the steeply dipping NE striking Waiotahi-Cambria vein, and associated splays. Hydrothermal alteration increases in intensity from isolated blocks of propylitic altered andesitic material, into the intensely clay altered equivalent. Low rank propylitic alteration is typified by chlorite, calcite and pyrite, with local illite or epidote. Clay alteration is characterised by illite, quartz, kaolinite and pyrite. While broadly forming halos around veining, intense clay alteration also occurs in strongly jointed portions of the hostrock.   Vein textures and the intense illitic clay alteration at Thames are similar to those in some of the other epithermal gold deposits of the Coromandel Volcanic zone, and in deposits of the Philippines, all related to andesitic terranes. Possible causes for textures and alteration being different in these deposits from the more classic Quartz-Adularia-Illite type epithermal systems may be that cooling/mixing rather than boiling dominates fluid evolution. Kaolinite may be also be a product of either of these different fluid types, or has resulted from overprinting of an illitic assemblage by downward percolation of acidic fluid.

Jan 1, 1991

Today computers are accepted as a standard item in industry and they perform a variety of tasks over a wide spectrum of activities from mine planning and CAD to data processing and spreadsheet work. However many problems particularly in the. area of decision making where there are no clear mathematical models available and usually the output or answer is dependent to some extent on a heuristic approach, don't lend themselves to conventional solutions using standard procedural algorithms. Recently a number of techniques have evolved primarily from the enhanced capabilities of modem equipment, which are capable of solving these problems. This paper is a brief overview of these rather unconventional developments of computer technology in the area of artificial intelligence with reference to their application in mining.

Jan 1, 1993

By Andrew A. A, Hamilton P. J

Constraints on pore water evolution in the aquifers of a sedimentary basin may be realised through stable isotope analyses of present day waters, and their comparison with water compositions calculated to have been in isotope equilibrium with the products of diagenesis during burial. Integrated with detailed petrographic observations, and thermal, structural and stratigraphic analyses, fluid migration patterns at various stages in a basin's history can be identified. This has important implications for modelling basin hydrology, hydrocarbon distribution, and reservoir quality in the Latrobe Group, Gippsland Basin, and oil-prone successions Elsewhere.

Jan 1, 1992

The interaction of flotation collectors with sulfide minerals takes place at the solid - solution interface. The electrochemistry of the processes which affect this interface are discussed. The interaction of xanthates with sulfides is an electrochemical process, xanthates being electro-oxidised to chemisorbed xanthate and dixanthogen. The role of oxygen is to provide a cathodic process to allow the anodic oxidation to occur. The hydrophobic condition of the mineral surface is brought about by the presence of the oxidised xanthate species. The action of reagents which can activate or depress the flotation of sulfides is discussed briefly.

Jan 1, 1971

CSA mine, which is a deep level copper operation, located 12 km north of Cobar, NSW, currently uses a top down stoping method, utilising cemented hydraulic backfill (CHF) to fill and stabilise the stoping void thus assisting the extraction sequence. The stope sequence then requires development back through the CHF stope so that the necessary infrastructure for the subsequent stoping, such as raise bore pads can be sited. The primary and secondary support installed in the CHF consisted of 100 mm thick fibrecrete from floor to floor with 7 + 2.4 m long resin support tendons installed at 1.5 m ring spacing. This support system relied on the resin achieving a quality bond with the CHF, and also the fibrecrete developing early structural strength due to the use of an accelerator. In addition to the delays in the excavation turn around time, it was felt that a superior support system could be designed. Such a system was designed; risk assessed, tested underground, and trialled in selective CHF digouts, and eventually signed off as the chosen support method in CHF digouts. This paper discusses the change from a passive support system used in CHF digouts to an active support system using Swellex bolts and weld mesh, which has provided an active support system, that is superior, faster to install, reduced the excavation turn around time and is overall a cheaper support system.

Nov 25, 2010

By Blott S. F

The smelting plant and equipment at Mount Isa, as originally designed and built, was described by J. M. Callow (1) *.F. A. Forward (2) described alterations and additions to the plant and discussed the metallurgy of mixed carbonate-sulphide concentrates at Mount Isa, prior to 1933, in the Proceedings of this Institute.In 1933, A. F. McAskill (3) gave full mechanical details of the plant in a paper presented to the Institution of Engineers, Aust.FLOW SHEETSFig. No. 1 represents the present general flow sheet. Forward's (2) flow sheet is reproduced here as Fig. lA, and will serve for comparison in depicting subsequent deletions from, and alterations and additions to, the plant.Fig. No. 2 presents the daily tonnage flow sheet of 1939 practice.ALTERATIONS SINCE 1933General. Many changes in metallurgy and operation have taken place, particularly subsequent to March, 1935, when the treatment of a mixture of carbonate and sulphide ores was discontinued and the mill commenced operating on all-sulphide ore. This alteration brought about the elimination of gravity concentration-Jigs and Tables and resulted in the production of all-floatation concentrates of a very fine sizing. Refer Table No. 2, page?) Radical changes in the analyses and physical nature of concentrates also followed (see Table Nos. 1 & 2, page ?) and, similarly, radical changes in the smelting plant have been slowly brought about.

Jan 1, 1939

By A F. Wilson

The use of stable isotopic measurements as a technique for elucidating the origin and history of the water in hydrothermal fluids is relatively new. Recent studies have emphasised the importance of meteoric water in the formation of many hydrothermal ore deposits including many epithermal gold-base metal deposits which occur in faulted volcanic terrane. Other vein-type gold ores are believed to have formed from fluids of magmatic or metamorphic origin and exhibit characteristic d180 values. These values also give information regarding temperatures and the degree of equilibrium. Preliminary oxygen data for some important gold deposits of eastern Australia are evaluated in the context of styles of mineralisation.

Jan 1, 1980

By A Harris, N Fitzpatrick, F MacCorquodale

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Gosowong epithermal Au-Ag deposits, located on the island of Halmahera, North Maluku Province, Indonesia, are owned and operated by PT Nusa Halmahera Minerals, a joint venture between Newcrest Mining Limited (75 per cent) and PT Aneka Tambang Tbk (25 per cent).The Gosowong deposit was a greenfields discovery in 1994. Subsequent brownfields discoveries, most recently in 2009, have resulted in a total endowment of more than 6 Moz Au. The three main deposits include Gosowong, Toguraci and Kencana, and as of December 2013, production comprised 5.7 Mt Au at 24 g/t for 4.3 Moz with remaining resources of 4.2 Mt Au at 13 g/t for 1.7 Moz.Mineralisation primarily occurs in multistage veins, breccias and stockwork veins, with at least four texturally- and mineralogically-distinct vein events, including: banded crystalline quartz, quartz-adularia, quartz-chlorite and quartz-sulfide stages. Vein mode, texture and mineralogy are zoned around areas of maximum dilation, vein width and vein grade. Within banded quartz-chlorite, grades of >1000 g/t Au are common. Anomalous Au-Ag-Pb-As-Sb-K-Li geochemistry in rocks is commonly associated with the epithermal mineralisation. Four major types of hypogene alteration are recognised at Gosowong: silicification (quartz-illite-adularia-pyrite) within the immediate vein zone, argillic (illite-quartz-pyrite) alteration enveloping the vein zone, advanced argillic (dickite-kaolinite-quartz) alteration above and adjacent to the vein zone and within the overlying Kayasa Formation, and propylitic (chlorite-epidote-albite-calcite-pyrite) alteration within the footwall and distal to the vein zone.CITATION:Fitzpatrick, N, Harris, A, MacCorquodale, F and Wardiman, D, 2015. The Gosowong goldfield – a world-class epithermal gold-silver district in Indonesia , in Proceedings PACRIM 2015 Congress, pp 235–242 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By P J. Cullen, B P. Banerjee, S Raval

Continuous monitoring of mining impacts on the surrounding environment is a necessary sustainability criterion. Traditional monitoring approaches such as in situ sampling and airborne and satellite-based remote sensing have several limitations. Over the past few decades, unmanned aerial vehicles (UAVs) have evolved into popular platforms for remote sensing. UAV-based remote sensing has been successfully applied in different sectors, including agriculture, forestry, urban environments and disaster management. However, the potential of UAVs for mine environmental monitoring has not yet been fully established. This paper envisages the use of UAVs and sensor systems to monitor the environment of future mines.CITATION:Banerjee, B P, Raval, S and Cullen, P J, 2015. Unmanned aerial vehicles for mine environment monitoring, in Proceedings Third International Future Mining Conference, pp 137–144 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By M K. de Brodtkorb

Late Cenozoic ore deposits æPrecious and base metal-richÆ and æSn-Ag-polymetallicÆ ofNorthern Puna are associated either with Middle Miocene dacitic volcanic-dome complexes or with Upper Miocene dacitic-andesitic volcanic centres.   Ore mineralogies and their related volcanism are discussed. A strong link is observed between the Cenozoic Metallogenetic Province of Northern Puna and the Southern Bolivia Tin and polymetallic provinces.  

Jan 1, 1995

The work to be described is part of a comprehensive research on the influence of impurities on the properties of lead. The author had previously compared an electrolytic lead containing less than 0.002% total impurities with a commercial lead containing 0.008% impurities (excluding oxygen) and had shown that the former recrystallised more readily than the latter under the same conditions of cold work and annealing. This difference in properties was attributed to the difference in purity. Electrolytic lead containing only 0.0005% total impurities has been prepared and cast in vacuo. Some interesting effects have been obtained by working and annealing this lead, and by adding silver to it. The preparation of this lead, and the effects obtained thereon, are described in this paper. Thepaper is divided into the following sections:(I) Preparation of electrolytic lead.(II) Vacuum Casting.(III) Effect of Cold, Work and Annealing on two Electrolytic Leads, having 0.002% and 0.0005% Total Impurities respectively.1 Research Fellow, Dept. of Metallurgy, University of Melbourne.2 Proc. Aust. lnst. Min. Met., 1932, 87, 145.

Jan 1, 1934

By H M. Ahmed, W S. Dunbar

Construction of cave mining systems requires significant capital expenditure and long-term commitment of human, equipment and material resources before production commences. Risks and uncertainties of these large-scale mining projects are significantly higher than for small-scale projects. This is due to the complexity and interactions of the construction schedule components and the large scale and uniqueness of such projects. One way to successfully manage construction uncertainties that would lead to schedule delays is to include a reasonable cost contingency in the budget estimation. A real options approach based on the least-squares Monte Carlo (LSM) method is used to estimate cost contingency associated with schedule uncertainty in mass mining projects. Cost contingency is estimated as the cost of potential project crashing (acceleration) decisions, which pays for not extending the schedule. While such a significant undertaking is expected to be subject to some delays, these can have an enormous impact on the economic value of such projects. The value of the crashing option was explicitly formalised into the process of valuation, as it is assumed to be a single option being considered in the valuation at every decision point prior to the construction completion date. As a part of the proposed method, a stochastic function for the percentage of remaining scope of work for the remaining duration of the entire project was integrated into a framework of numerical simulations. This ensured that this function can implicitly account for sources of schedule uncertainties for projects represented by multiple and overlapping work packages. The LSM method was applied to a real case scenario in an operating block cave mine, with modified scale and features. The results yielded by the LSM method indicated that significant changes in capital budget allocation stem from variation in a contractor’s risk perception and confidence level of estimated delays.CITATION:Ahmed, H M and Dunbar, W S, 2016. Budget estimation and contingency allocation of block cave construction using least-squares Monte Carlo real options, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 801–808 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By R Cowen

Past successes of low impact mineral exploration and rehabilitation of mined areas in developed land of subdued contour provide little guidance for similar activity in more sensitive high country or mountain environments. Land management agencies and environmental pressure groups have expressed considerable concern about mineral development in these areas by land especially where the land involved has high environmental or productive values. Mineral explorers are responding with detailed proposals for integration of environmental assessment and mineral exploration at an early stage. A model programme for Fiordland National Park presented in this paper illustrates this approach.

Jan 1, 1981