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By G D. Carman

White Rock is a reduced tungsten-tin skarn deposit near Rye Park, New South Wales. This abstract summarises the depositÆs mining and exploration history, and current exploration by Paradigm Metals Ltd targeting an economic resource at the deposit. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Thimons E. D, Derick R. L

In early June, 1986, a fire of unknown origin erupted in one of several main entries of a coal mine located in southwestern Colorado. The fire was aggressively fought with high-expansion foam. As a result of several strategic decisions, the fire appeared to be held in-check. Unfortunately, sufficient quantities of foam were unavailable and as soon as the foam was depleted, control of the fire was lost. To prevent further damage and the possibility of an explosion, all entries to the mine were sealed.

Jan 1, 1988

By M J. Schultz, R L. Rude, D M. Tomko

The US Mine Safety and Health Administration (MSHA) conducted compliance assistance diesel particulate matter (DPM) sampling throughout the underground metal and non-metal mining industry. Based on that sampling, MSHA identified mines that were having difficulty meeting the DPM limit. To provide further assistance, MSHA then visited approximately 60 of the mines that were experiencing difficulty complying with the DPM standard. As part of these visits, DPM exposures were measured and control technologies for DPM were observed and assessed. Controls consisted of ventilation, clean engines, environmental cabs, alternative fuels, diesel particulate filters (DPF) and work practices. The focus of the follow-up compliance assistance visits was to assess control effectiveness and to make recommendations to mines experiencing difficulty in meeting the DPM standard. At each mine visited, the ventilation controls were evaluated, engine emissions were determined for equipment in use, environmental cabs were examined, and operational practices were noted. Additionally, control technologies, including alternative fuels and DPF were evaluated in several mines. A comparison was made of mine and section airflow to equipment particulate indices. Based on engine emissions, horsepower and operating time, the contribution of individual engine emissions to total emissions was made. Environmental cab integrity, positive pressure and air filtration systems were checked and operational practices relating to DPM exposure were assessed. This paper summarises the preference and magnitudes of controls that were typically used or needed for successful control of DPM. Additionally, results of the assessments of alternative fuels (including bio-diesel and water emulsion fuels) and DPF are presented.

Jan 1, 2005

By Sorokin M, Komkov A, Fyodorov A

The Vanyukov Process is a high-intensity smelting system that has been proven over the last 20 years for various metallurgical operations including the smelting of copper, nickel, copper-zinc, antimony concentrates, municipal waste treatment and pig-iron production. Extensive pilot plant tests on copper and copper-nickel concentrates have provided information for the design of the commercial furnaces. The thermodynamic analysis, design idea and the data obtained from commercial furnaces have shown that Vanyukov Process would be the best choice to smelt copper-nickel and nickel sulphide concentrates as well as oxide nickel ores.

Jan 1, 1996

By Galecki G

The investigations conducted in the High Pressure Lab at the University of Missouri-Rolla demonstrated the ability of high pressure waterjets to excavate coal and minerals, disintegrate materials and as well as to comminute coal and minerals. Additional progress in comminution can be achieved if the compressive crushing principle commonly used at present is changed to one where particles are fragmented by the tensile growth of preexisting internal flaws or cracks, under internal waterjet pressure. This idea was studied in a number of tests. It covers tests with different jets imposed on coal and rock samples during compressive load as well as without any loading.

Jan 1, 1993

By B Tadesse, L G. Dyer, B Albijanic, M Jung

The presence of high concentrations of dissolved ions in groundwater, sea water or recycled water may alter the water structure, particle surface wettability and colloidal interactions between bubbles and particles and can have a significant effect on mineral flotation. While the impact of water quality on the flotation of precious and base metal minerals is well established, no relevant published study exists currently regarding the effect of water salinity on the flotation of rare earth bearing minerals. This paper attempts to quantify the effect of water quality variation on flotation recovery and grade of rare earth minerals and gain an understanding on which ions existing in saline water affect flotation behaviour. Specifically, it is aimed at investigating the effects of water quality on the flotation of monazite in the presence of cations such as Ca2+, Mg2+, K+, and Na+. Flotation tests, zeta potential measurements, and adsorption tests were performed to explain the flotation behaviour. It was found that monovalent ions such as Na+ and K+ have negative impact on rare earth minerals recovery and grade. The result of single mineral flotation tests showed that the floatability of monazite was significantly depressed in the presence of Ca2+ and Mg2+. The result of single mineral flotation test showed varying depression levels in the presence ions in the order of Ca2+ > Mg2+ > Na ~ K.

Aug 24, 2022

The gossan developed from the Whim Creek Cu-Zn-Pb-Ag sulphide deposit, in the Pilbara region of Western Australia, occurs near the top of a ridge in a dissected plateau 01 moderate relief. The gossan is characterized by the abundance of secondary ore minerals which indicates that it is relatively immature, due to climatic conditions and erosional stripping.The abundant presence of secondary carbonates indicates that the low pH generally resulting from sulphide oxidation has been neutralized, probably by the buffering effect of carbonatcs and silicates. Fe, Cu, Pb, 'Ag and Sn have been enriched in the gossan relative to the primary ore, and Mn, Ti, Co and Ni have been strongly depleted; other elements have remained substantially unchanged. The gossan has a strong gcochemical signature characterized by high Cu, Zn, Pb, As, Sb, Sn, Ag and Mo coutents. Boxwork textures are poorly developed, bu't the gossan has other diagnostic mineralogical features including sulphide inclusions in quartz and the presence of residual cassiterite.

Jan 1, 1982

By Baafi E. Y

Dragline monitoring systems are normally the best tool used to collect data on the machine performance and operational parameters of a dragline operation. This paper discusses results of a time study using data from a dragline monitoring syste

Jan 1, 1998

By Olofsson O, Durance M-V, Villeneuve J

Modelling of the Sala Agitated Mill (SAM) using a simplified solution to the population balance approach has been carried out. The rate of breakage is modified by the mill power, providing predictions of the resulting product size distribution for different grinding conditions and mill sizes. The power of the mill is estimated by a physically derived function, using an assumption that the mill power consumption mainly arises from the ball to ball friction within the mill. The grinding efficiency, depending on the media ball size and pulp density is approximated in the model. Experimental work on grinding a complex sulphide ore using a pilot scale SAM 7.5 has been carried out. Good agreement has been found between the data from the test campaign and the simulated values. The model has also been validated with experimental data from a pilot grinding of calcium carbonate and from an industrial mill. The model is included in the USIM PAC simulation software.

Jan 1, 1995

The role of metals in the economy is discussed with regard to the flow of metals through to final demand and is illustrated by data for seven metals. Factors influencing the changing pattern of metal consumption are described, including relative prices. A des- cription and discussion of current metal demand forecasting methodologies precedes a discussion firstly of broad economic trends and secondly of the evolving pattern of metal consumption relative to GDP (metal consumption intensity), as technology and other factors change and as economies mature. The tendency for metal consumption intensity to plateau and decline when economies reach a certain region of per capita GDP, following a rapid rise early in the industrial- ization process, is shown in comparative data for seven metals and six countries.

Jan 1, 1979

By Fulton E, Ring RJ, Waters DJ

Laboratory leach tests of Nabarlek uranium ore carried out by the Australian Atomic Energy Commission to compare the effectiveness of Caro's Acid1 (permonosulphuric acid) as an alternative oxident to pyrolusite indicated reduced acid consumption in leaching and lime savings in neutralisation of tailings liquors when using Caro's Acid. Interox Chemicals Pty. Ltd. arranged a plant trial for Caro's Acid at Queensland Mines Nabarlek Plant. The trial confirmed that significant savings in acid and lime can be achieved under plant conditions. Plant operations also demonstrated improved redox potential control was possible using Caro's Acid.

Jan 1, 1978

By Caivin JS, Freeman CJ

The Fairbanks Mining District in central Alaska was discovered in 1902 and since then approximately 7.5 million troy oz of placer gold, 250,000 troy oz of lode gold, and several thousand short tons of antimony and tungsten hap been produced from an area of about 1000 km . Historic lode production was from high grade gold-quartz veins that averaged 1.3 OPT free milling gold. Five main types of mineral deposits' are recognized in the district. I. Conformable, stratabound volcanogenic zinc, antimony, lead, and copper sulfides in places containing gold, silver and tungsten in bimodal metavoleanics (Cleary Sequence). II. Complex precious metal-bearing lead sulfosalt-quartz veins in Cretaceous granitic intrusives. III. Tungsten skarns adjacent to granitic intrusives. IV. Gold-bearing polymetallic sulfide-quartz veins crosscutting metavolcanics and metasedimentary units of the Cleary Sequence. V. Antimony-bearing gash veins along axial plane shears in various lithologies of the Cleary Sequence. Type I and Type IV mineral occurrences are currently being evaluated as low. grade bulk tonnage (target model 16-20 'million tons of 0.05 to 0.15 OPT)'and high grade moderate tonnage (target model 0.5 to 2.5 million tons of 0.5 OPT) gold deposits. The host rocks for Type I mineralization occur over a 30 km strike length and are at least 300 meters thick. Stratigraphic, structural, fluid inclusion, and isotopic data suggest that the Type IV mineralization is related to remobilization of Type I

Jan 1, 1987

By Riches N, Harbort G

The Jameson flotation cell was developed jointly by Mount Isa Mines Limited and Professor GJ Jameson of the University of Newcastle. The cell has been used in a number of cleaning applications within Mount Isa Mines Limited. In 1989 Peko Mines tested the Jameson flotation cell at the Warrego concentrator to upgrade recleaner concentrate. 2 x 1.4 m diameter Jameson flotation cells were installed in 1990. This paper describes the testing, commissioning and operation of these Cells.

Jan 1, 1991

By Crapp C. E

The Collinsville Coal Measures consist mainly of arenaceous sediments but indude eleven named coal seams. The Formation outcrops around the northern end of tbe Bowen Basin where it attains a thickness of 700 ft. in the Collinsville-Scottville area and overlies Lower Bowen Volcanies with angular unconformity. Most of the members in the Formation thicken basinwards. The regional dip is about 8 degrees. The Formation thins southwards and does not occur south of the Bowen River on the eastern flank. On the western flank it is represented by 60 ft. of barren sandstone at the limit of our mapping, 12 miles south of the Bowen River. Two seams are mined, the Bowen and the Blake; coal from the former produces high grade metallurgical coke, and the latter seam is mined for steaming coal. Where mined, the seams are about 20 ft. thick. The coals are of medium volatile bituminous rank and the lower coals are of higher rank than those above them.Reverse faults striking across the Coal Measures have been delineated and the existence of areas of intrusive rocks has been established. Intrusions rose up fault planes and, as felspar porphyry sills, selectively intruded coal seams, decimating reserves of coalavailable for mining. One sill, in the Blake Seam, attains a known thickness of 115 ft. Because the distribution and thickness of the sills is rarely predictable, density of drilling has been greater than in most coalfields.INTRODUCTIONThe assemblage of sediments occupying the northern portion of the Bowen Basin (Fig. 1) may be divided into four formations of Permian age:The Upper Coal Measures (U. Bowen)The Middle Bowen Marine Beds (M. Bowen)The Collinsville Coal Measures (M. Bowen)The Lower Bowen Volcanics (L. Bowen).Of these, the Upper Coal Measures and the Collinsville Coal Measures are known to contain coal seams of workable thickness.

Jan 1, 1960

Pisolitic iron ores (also known as channel iron deposits) are an important resource of medium-grade iron ore in the Hamersley Province of Western Australia. They are a special case of transported pisolitic ferricrust, differing from normal transported ferricrust only in the exceptionally high iron and low alumina content. The pisoids typically range up to 5 mm in diameter with abundant particles of ferruginised fossil wood up to 15 mm in maximum diameter preserved in the sediment. Field observations indicate that pisoliths are commonly initiated by the action of raindrops on iron-rich soil. Pisolites form by the impact of raindrops forming coated beads of ferruginous soil, which after dehydration obtain additional coatings during successive showers. Thick deposits of pisolite that are transported and deposited primarily by sheetwash form in the distal regions of the pediment. A size range limited to particles that may be transported by extremely shallow water characterises the abundant fossil wood fragments. The absence of fine sedimentary layering in pisolitic iron ores is explained by the action of soil-forming processes after deposition, while the major coarse bedding features derive from successive erosional and depositional events in the evolution of the pediment. They are not deposited in channels by rivers which, in arid to semi-arid conditions, typically deposit quartz sands and gravels with characteristic point bars and current bedding, abundant ferruginous granules, but rarely pisoids. However, they may fill abandoned river channels.

Jan 1, 2007

A simulation model of the load and haul process where the loader cycle has been subdivided into its individual components is used to consider the benefits derived from improved drill and blast methods. Field data from a Hunter Valley mine is u

Jan 1, 1998

INDEX OF CONTENTSIntroductionThe slag samplesGranulated SlagGlass-spinel-magnetite-metallic leadRapidly Chilled SlagSlowly Cooled SlagSpinel - magnetite - zinc melitite (hardystonite) willemite - olivine -lead silicate - metallic lead - lead sulphide - copper sulphide - copper arsenide - nickel arsenide.ConclusionsIllustrationsINTRODUCTIONThis paper presents the results of a mineragraphic examination of representative samples of granulated lead blast furnace slags from the Port Pirie Smelter, and of slowly cooled samples of t:b.e same slags, undertaken at the request of the Broken Hill Associated Smelters Pty. Ltd., as part of the research programme of the Mineragraphic Section of the Commonwealth Scientific and Industrial Research Organization.THE SLAG SAMPLESThe chemical composition of the slags examined is given by the following three analyses of the granulated slags, supplied by the Broken Hill Associated Smelters (Table 1).

Jan 1, 1949

By R E. Conder

A major initial and ongoing cost component in many mining operations is that of transporting mined materials and processed ore from the point of extraction or processing to the next operation. For various reasons the transport distance can be significant or in some cases the route may be particularly challenging. The trend to higher production rates to gain economy of scale benefits and capitalise on sales opportunities means that optimisation of transport can play a significant part in profitability. Apart from the cost criteria, increasingly there are other criteria such as environmental restraints, land ownership and security of supply that can have a significant impact on determination of the optimum route and transport vehicle. The paper aims to briefly highlight the important selection criteria and the benefits and disadvantages of the most commonly utilised transport vehicles. It then moves on to looking in more depth at belt conveying, highlighting the unique capabilities of the Metso MRC Cable Belt Conveyor system.

Jan 1, 2004

By Brien R. J, O&apos

Faster and more efficient methods of producing and refining iron and steel are imposing severe conditions on the refractory materials used to contain these metals in the molten state. In order to provide refractory linings which will give the desired service life and maintain unit availability at an economical level, it is necessary to appreciate the aggressive environment in which the refractories operate and determine the reaction mechanisms by which the refractories are destroyed. Only by such studies can the most suitable refractory or refractory combination for a particular unit be selected. Examples of refractories selection and reaction mechanisms are discussed for blast furnaces, BOS vessels, AOD vessels, steel ladles, vacuum degassing units and continuous casting.

Jan 1, 1976

By Boland J

Prediction of rock cuttability by various excavation machines such as tunnel boring machines, road headers, rippers, picks, roller disc cutters, excavators, etc is of major concern to both civil and mining engineers and rock mechanics. In principle, the design of a rock cutting tool is based on achieving maximum excavation with minimum input energy, minimum applied force, minimum equipment weight and volume and, more importantly, minimum tool wear. When a rock material is indented by the force of a cutting tool and then unloaded several material zones form underneath and around the tool. As the tool moves into the rock the volume of its associated rock cavity (ie volume of displaced rock) expands and depending on the indenter's shape various phenomena may occur. Immediately beneath the tool a small zone in which the stress state is more or less hydrostatic, is formed which is underlain by an inelastic, or damaged, material zone. Both size and shape of this damaged zone control the magnitude of the indentation force and the chip formation mechanism during unloading. The rock is unable to store the whole strain energy induced by the tool and consequently the extra energy is expended either in forming new fracture surfaces and/or in plastic deformation in the damaged zone. Therefore, it is not surprising to see that both perfect-elastic and rigid-plastic constitutive models are not generally suitable for modelling indentation of rocks. In contrast elastoplastic constitutive models are more appropriate as they can include both elastic and plastic deformations (Kral et al, 1993). Elastic solutions for several half-space indentation problems can be found in most text books on elasticity and in particular in Timoshenko and Goodier (1951), Sneddon, (1951), Poulos and Davis (1974) and Johnson (1985a). If a failure criterion, eg the Mohr-Coulomb failure criterion, is applied to delimit elastic solutions for indentation problems, a lower bound limit of the applied indentation force (for a given indentation depth) can be estimated. It may be noted that elastic analyses, without any delimiting failure criteria, normally overestimate the indentation force. Plastic solutions for a few indentation problems may be found in Hill (1950), Johnson, (1985a) and Alehossein et al (1992). When analysing the behaviour of indented rocks the choice of an appropriate constitutive model describing effectively the behaviour of the rock at various stages and phases during indentation is a challenging issue. Several questions need to be answered before starting an effective analysis. The first question is of course: Which one of these is more appropriate for modelling zones underneath and around a cutter, elasticity or plasticity theory, continuum damage mechanics or fracture mechanics, and what is the bridging link between these various theories? Which mode is more dominant in fracturing rock, tensile or shear mode? What governs the mechanism of chip formation? What is the function, shape and the behaviour of the pulverised zone that forms just underneath a cutter? Is the hydrostatic stress state assumption reasonable for this zone? How does the rock change during the absorption and dissipation of the input energy and how does the indentation energy vary with rock type and depth of penetration? How can we model the damaged zone under the indenter? Furthermore does a plastic material form beneath the pulverised zone? When and how do radial and ring cracks form around and under an indenter?

Jan 1, 1995