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Beaches contain the residue of eroded rocks which have resisted weathering, and it is common to find in all beaches some of the harder, heavy minerals. The natural sorting action of waves and winds tends to concentrate the heavy minerals into banded deposits.The value of such deposits is extremely variable. Even amongst the more concentrated deposits, the principal minerals, in the vast majority of cases, are magnetic, titaniferous magnetite and other forms of iron oxide, which, in the present state of mineral economics and technology, are of little or no value.Valuable minerals of fairly common occurrence in beach sand deposits are rutile, zircon, ilmenite, monazite and chromite, and each of these minerals, as well as others of less common occurrence, is obtained from beach deposits in various parts of the world.Along a stretch of 300 miles of coast from Coff's Harbour in New South Wales to North Stradbroke Island in Queensland, occur unique concentrations of heavy minerals. The principal minerals which occur are rutile, zircon and ilmenite, and for some years these deposits have contributed half to three-quarters of the world's consumption of rutile and zircon 1, ,2. The only other notable beach sand concentrations in Australia are at a number of places in the southwest of Western Australia, where deposits containing highgrade ilmenite are being developed.

Jan 1, 1950

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

The ready solubility of gold in dilute aqueous solutions of the cyanides of the alkalies or alkaline earths provides a convenient method for the separation of the precious metal -from the large surplus of associated materia1. The finely ground ore is pulped with a weak solution of cyanide, agitated to dissolve the gold, filtered and washed. The lowgrade filtrate is then clarified and the gold precipitated by some electronegative agent, the most usual being finely divided zinc or zinc dust. The slight precipitate is collectedon some form of filter coated with a filter aid, the filter cake being then known as "gold slime".A typical analysis of this slime is given in Table 1.

Jan 1, 1956

By T Hughes

The Gekko InLine Pressure Jig (IPJ) was unleashed on the World gravity separation market in 1996 and has since sold over 150 units in applications including tin, diamonds, silver, coal, garnet and gold. During the past twelve years the knowledgebase of the best applications and capabilities of the IPJ has greatly increased. Improvements to the original IPJ design have included engineered ceramic ragging in specific gravities from 1.6 to 5.0, full automation and improved designs of feed presentation and tailings and concentrate handling systems. The IPJ has been found to be able to handle a wide feed size range and recover mineral at liberation size without significant addition of water to the mass balance. Test work carried out during full-scale operation of the IPJ has shown the IPJ can recover diamonds down to 0.5 mm, sulfides down to 0.3 mm and gold down to 0.1 mm which greatly expands its application in the mineral processing industry. A significant volume of data now supports the symbiotic benefits of an IPJ and flotation circuit combination to pre-concentrate an ore and minimise downstream processing requirements.

Jan 1, 2008

By Probert D. H, Wright E. A, Taylor B. L

A general description of the geology of the Southern Coalfield is given. The relationship between the Illawarra Coal Measures, the overlying Triassic and the underlying Upper Marine Series, of Permian age as are the Coal Measures, is briefly explained and thestratigraphy of each is described. The eight coal seams are then treated in slightly more detail as to their thickness, quality, areas of distribution and best occurrences.In the last few years each of the authors has been concerned with one phase or other of the stTucture of the field in detail or in mining operations with the result that it is now possible to name a number of monoclines, anticlines, domes and synclines defined in detail. A minor quantitative study has been made of faults and dykes with regard to form, direction intensity and inter-relationship. It seems probable that with the further collection of data a more detailed study in these matters will be of considerable value to the economy of mining in the Southern Coalfield.

Jan 1, 1958

To the industrial geologist, as wen as to the general or historic geologist, the possession of a reliable key to the true order or sequence of the stratigraphy or position of the various upper rocky envelopes of the earth's crust, is, equally, a desideratum of the utmost importance. Of similar value to the two groups of students is the possession of facts which throw light upon the relationships which subsist between the puccessive rock formation of different countries, especially between countries lying close to each other, or within the same great geographical division.But there is necessarily a fundamental distinction which marks the respective limits of the field of observations of the industrial geologist, and the purely historic interest of the general geologist. The former has a more definite though less extensive scope. The scope of the latter is wide and indeterminate. In short, the observations of the industrial geologist are, 'from a commercial or economic point of view, of a more practical character, and are, therefore, intentionally restricted to the study of all geological questions which throw light upon the rocks which yield products of economic value and only include the study of the character and history of other rocks, in so far, as they afford aid to the more perfect comprehension of the best manner in which materials of economic value are likely to be sought, and the best means whereby these products may be secured for the material advantage of the community. The motive of the general geologist-in most cases-is a love of the study of some particular branch or province of the geological field, and the fascination of opening a new volume in nature's library, and the hope of extending the realm of knowledge, however slight, are often sufficient, as a motive, to enlist the energy and life's devotion of the true brethren of the hammer, irrespective of considerations regarding the commercial utility of the pursuit.

By Orr C. W

Continuing the systematic investigation of the influence of elements on the properties of lead(1). If the effects of additions of copper (up to 0.3%) on Port Pirie lead have now been determined in so far as creep rate is concerned.The results in the present paper contain also a survey of the influence of copper on the micro-structure of lead, a feature which has not appeared in the previous papers of this series. Further, it has now become known that creep is but little related to the more usually determined properties such as hardness and tensile strength. Since, however, these properties are of considerable importance in connection with the fabrication and use of this metal. Brinell hardness determinations have also been made and are here included.It is becoming more and more realised also that to be useful, creep data should refer to stresses of the order of those used in practice. This is due to the fact that as soon as deformation takes place, the properties of the metal are automatically changed. Lead does, of course, creep during industrial use, and probably (in lead chamber construction for example) extensions of the order of 5%...

Jan 1, 1938

Bioleaching Metals from Waste Printed Circuit Boards and the Shapes of Microorganisms

Sep 13, 2010

The Greymouth Coal Project is a proposal to mine by the application of proven hydraulic, and room and pillar underground mining methods; and to process the equivalent of an average of 1.7 million tonnes per year over a forty-year period. The proposed mine site is located ten kilometres north of Greymouth, on the west coast of the South Island of New Zealand. Of the three separate mineable seam groups, the thick Main Seam Group, which makes up 77% of the total resource, will be mined by hydraulic mining technology.   It is proposed to market and produce a high volatile bituminous type coal with low ash (6%) and sulphur (0.4%). Because the inherent ash content is low, the requirement for coal treatment will only be the use of a single cell jig circuit to control the effects of rock dilution and partings. The resulting coal product is tentatively planned to be transported by rail to the port at Lyttelton for loading on to Panamax or Post Panamax size vessels.

Jan 1, 1997

By A Audétat, W T. Li

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Middle and Lower Yangtze River metallogenic belt is one of the most important polymetallic resource areas in China. Iron oxide-apatite deposits, mainly distributed in Ningwu and Luzong volcanic basins, are a distinct type of iron deposits in this region. These deposits have a close temporal and spatial relationship with Mesozoic dioritic porphyries and are characterised by magnetite-apatite-pyroxene/actinolite ± anhydrite assemblage and large-scale sodic-calcic alteration.Widespread multiphase inclusions in pre- to main-mineralisation stage pyroxene and garnet in Meishan (in the Ningwu basin), Luohe and Nihe (both in the Luzong basin) iron deposits were trapped at ~780°C in extremely saline brines (~90 wt per cent NaCl equivalent), consisting of Na (13–24 wt per cent), K (7–11 wt per cent), Ca (~7 wt per cent), Fe (~2 wt per cent), Cl (19–47 wt per cent) and SO4 (3–39 wt per cent), based on petrologic, microthermometric, Raman spectroscopic studies and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of natural fluid inclusions and synthetic analogues. The high Cl/Br, Na/B and S/B ratios in brine inclusions and the heavy sulfur isotopic values of anhydrite and pyrite (d34SAnh = +15.2 to +16.9‰, d34SPy = +4.6 to +12.1‰) suggest a significant contribution from both halite- and anhydrite-bearing sedimentary rocks. The involvement of evaporites caused the production of large amounts of high-salinity brines with apparently enhanced capacity to extract iron from the dioritic intrusions.According to their geologic features and the above characteristics, these iron oxide-apatite deposits are considered to be a special type of iron oxide copper gold (IOCG) deposits characterised by high contents of Na, Ca, Cl and SO4 in the ore-forming fluids. Moreover, we believe that evaporite-bearing sedimentary basins are more prospective than evaporite-free ones for these kinds of deposits.CITATION:Li, W T, Audétat, A and Zhang, J, 2015. The connection between evaporites and iron oxide-apatite deposits, Yangtze River, China – laser ablation inductively coupled plasma mass spectrometry analysis of Na, S, Cl and Br in fluid inclusions, in Proceedings PACRIM 2015 Congress, pp 623–630 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

The district specially referred to in this paper comprises the very gently sloping country extending from the western shores of Port Phillip from the mouth of the Yarra to Footscray along the Bacchus Marsh railway to near that town thence in a southerly direction to the Little River, and along that river to the coast, 1 as may be seen on the accompanying map. Almost the whole of this area is covered by volcanic rocks, consisting of pumerous sheets of basalt, which have been poured out of various volcanic hills in the districts, such as Mts. Atkinson and Cotteril, near Melton; Mt. Maryand Bald Hill, 12 and 16 miles respectively N.W. of Werribee; and vents in different parts of the parishes of Tarneit, Mouyong, Mooradoranook, Pyweitjorrk, and Derrimut. These volcanoes were in an active state of eruption during a late period of the earth's historyprobably the late Pliocenll, or still younger Pleistocene.Occupying a narrow strip of country, for most of the distance along the coast from Williamstown to past the mouth of the Little River, there occur deposits of still younger age, belonging to the Recent period. These lie on the basalt, and extend for distances varying from a few chains to more than a mile back from the beach. They comprise superficial deposits of blown sand, and raised beaches, composed of marine sands...

Jan 1, 1902

At Copper Refineries Pty. Ltd., Townsville, two reverberatory furnaces of 420 tonnes capacity are used to melt 210000 tonnes/year of copper for subsequent anode casting. When the refinery commenced production in1959, these furnaces were of 300 tonnes capacity. The original furnaces featured a silica brick hearth, magnesite and chrome magnesite side 'walls, and a sprung silica brick roof, but were unsatisfactory because of thelow refractory life and high costs. With continuous expansion in production and the incentive to increase furnace life and capacity the design of these furnaces has changed greatly since that time.The present furnaces feature all basic brick, a flat suspended basic brick roof, very extensive use of watercooled copper sections, and are of substantially increased (420 tonnes) capacity. Particular attention has been concentrated on high wear areas such as the taphole, side walls, and charging door jambs. Each furnace in its 24 h cycle, is charged, the copper melted, impurities skimmed off, metal "poled" prior to casting, and cast.The service condition during each of these operations is important in considering furnace refractory life.The improvements in operating practices and furnace 'construction which enabled the capacity of the furnaces to be increased are discussed. The life between major repairs to side walls has increased from 90 charges to300 charges.The scope for future improvement is considered and areas for development are suggested.

Jan 1, 1977

As far as is known at the present time, important ore occurrences at Mount Isa are restricted to the Urquhart Shale. These occur at Mount Isa itself, and some 13 miles north along strike at the Northern Leases.The primary silver-lead-zinc and copper orebodies occur as adjacent but discretc entities in lithologieally distinct host rocks. The copper orebodies occur in an envelope of "Silica Dolomite", whereas the silver-lead zinc orebodies occur in shale typical of the Urquhart Shale in general.At both Mount Isa and the Northern Leases, secondary lead orebodies occur at thc surface representing primary stratiform silver-lead-zinc sulphide accumulations in the fresh rocks at depth.Secondary copper orebodies are known only at Mount Isa, where they have formed in favourable environments, but unlike the secondary lead orebodies, not in the positions of the former primary mineralization that gave rise to them. The secondary copper is localized in shale remote from the point where the copper was released into solution by weathering. It was derived from very low grade fracture fillings and disseminations of chalcopyrite in the outcropping or suboutcropping crest of the "Silica Dolomite".Primary silver-lead-zinc orebodies arc oxidized without significant transport or secondary enrichment, but secondary copper orebodies arc characterized by considerable transport and extreme secondary enrichment.The original water table stood at approximately 1,150 ft (mine datum) and for the majority of the mine area controlled the base of complete oxidation fairly closely.An oxidized zone approximately 175 ft deep is general in the Urquhart Shale.Structures affecting ground conditions have influenced oxidation and leaching of the silver-lcad-zinc orebodies, and have had effects vital to the formation of secondary copper orebodies.

Jan 1, 1966

About 15 per cent of total electricity (400 MkW) was generated by nuclear power plants in the world (2009) and about 36 000 tons of uranium has been mined in uranium mines annually. Radioactive waste material is produced from uranium mines and nuclear power plants. The wastes must be disposed or stored safely for long-term. If they leak and/or move from disposal or storage sites due to air/groundwater flow, then a serious environmental pollution can occur. Hence, multi-layer system has been proposed and employed in order to seal off these radioactive waste materials from biosphere. Basically, bentonite is now used for establishing absorbing and sealing layers in this system. However, the amount of high quality betonite is very limited and in some cases it is hard to be obtained.On the other hand, a great deal of refuse from coal burning plants is produced every year and the amount of it is expected to be higher each year, especially in developing countries. More than half of flyash is utilised and the remaining is disposed at the disposal sites. However, the life of the disposal site is limited and it is diff cult to find a new disposal site. It is requested that the percentage of the utilisation of the flyash be increased in every field.From the above two points of view, a flyash-based barrier layer/cover system is considered in this research and this paper discusses the applicability of flyash as a content of barrier layer/cover material based on the results of a series of laboratory tests.

Dec 6, 2010

By J Guo, K Williams, J Y. Guo, A W. Roberts, M Jones, B Chen

Numerical simulations using the discrete element method (DEM) were carried out to investigate the flow patterns and stress field redistribution at the hopper and feeder interface. The influences of different filling heights, belt speeds and clearances between the hopper bottom and feeder surface on feeder loads were studied. Meanwhile, experiments were conducted by utilising wedged plane-flow hoppers with different configurations and horizontal feeders with various clearances. The simulation results were compared with theoretical values and experimental measurements. In terms of the cases presented in this study, simulation results reveal good agreements with experimental observations regarding the flow pattern. Being similar to the theoretical values, the simulations provide close predictions on vertical feeder loads for steady flow states, but they may show significant overestimations for initial states. Additionally, suggestions are given for relevant simulation parameters based on the comparisons shown in this investigation.CITATION:Guo, J, Roberts, A W, Williams, K, Jones, M, Chen, B and Guo, Y J, 2017. Simulation investigation of flow patterns and feeder loads at hopper/feeder interface, in Proceedings Iron Ore 2017, pp 173–182 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

Influence of Frothers on Bubble Shape and Velocity Close to the Generation Point

Sep 13, 2010

By Cooper R. J

The essential features of the zinc concentrate roasting installation at the Risdon Works by the Electrolytic Zinc Company of Australasia Ltd. are given.The problem of maintenance of ignition in down-draught zinc concentrate flash roasters is discussed, and a solution offered.A successful and economical method of using by-product oxygen for raising the roasting efficiency of hearth roasters is described. Three methods of utilizing oxygen for the same purpose in flash roasting are detailed, and their relative merit, considered.INTRODUCTIONThe zinc sulphide concentrate used at the Risdon Works is roasted autogenously for removal of sulphur in two hearth roasters, and four flash roasters. The hearth roasters are of modified Skinner type with eleven hearths. They were designed, and are used, for roasting mixtures of relatively low sulphide content. Their design and operation have been described elsewhere (Forster, 1949).The flash roasters are down-draughted furnaces with cross-section and rabbling equipment based on the hearth roaster design, and the process is similar to that developed by the Consolidated Mining and Smelting Company of Canada Ltd. (Cominco) at Trail, B.C. (Stimmel, Hannay, and McBean, 1936).These furnaces are 20 ft. in diameter. They have three drying hearths through which hot gas is drawn from the combustion chamber by the burner fan. The combustion chamber is 2'1 ft. high above the collecting hearth (27 ft. in No. 4 unit), and the discharge hearth below it is 6 ft. high, so that a large gas offtake is possible. Four rabble arms for each hearth are carried on a central column. Dried, ground concentrate, and the air for roasting it, are fed to a burner...

Jan 1, 1958

Detailed petrographic analyses of coal seams from the Newcastle, Illawarra, and Lithgow Coal Measures were made for a number of localities for each of twelve seams. From these analyses characteristic standardprofiles were derived for each seam. Two broad types of profile were found; one in which vitrite-poor and vitrite-rich layers alternate, and another in which there is a steady decrease in vitrite from the base to the top of the seam. From comparison of the petrographic profiles it was concluded that the Great Northern Seam in the Northern Coalfield is a possible equivalent to the BulIi in the Southern; and likewise the Fassifern to the Balgowni...

Jan 1, 1967

Possibilities and Working of the Specific Agglomeration of Fibrous Materials and Residues Plant based fibrous materials are becoming of increasing interest in a multitude of industrial applications. Main advantages are the specific lower energy demand and virtually closed CO2 cycle, excellent mechanical properties based on low density as well as a high level of recyclables. In contrast, processing and handling of such materials is associated with a number of challenges. These challenges are mainly related to specific morphological characteristics in correlation to fibre length and structure (branching and splices). Specific problems in further processing steps including transport, dosage or storage for natural fibre compounding, result from form-locking bonds leading to burling, clusters or plaits. Technologies of fibre processing are well known, but other than textile based technologies they generally result in intermediate goods which do not allow direct industrial application. The investigation to be presented is based on results of recent research activities and shows two possible technical solutions of innovative fibre agglomeration procedures. These methods allow the conversion of middle to long fibres into a form, which eases further processing and dosage significantly and therefore allows free flowing too. The procedures are based on the working principles of rolling and winding technology. Within the work, both of the patented methods and their respected lab-scaled devices will be described. Further, results will be shown for an up-scaled rolling agglomeration unit applying the developed principle and consisting of multiple process zones. Possible variations of the resulting product characteristics and the impact of different process parameters will be discussed based on the trials with natural fibre (hemp and flax) agglomeration. As a main outcome of the research, product qualities can be supplied according to the requirements of the specific application in correlation to agglomerate strength, porosity or form. In conclusion, recent developments for specific methods of characterization will be depicted.

Sep 13, 2010

By A Hanna

Quarries around Auckland have reached or are reaching the ends of their lives, which raises issues about rehabilitation. Significant volumes of 'cleanfill' are generated by the City, particularly during phases of urban renewal and development. Emplacement of the fill in quarries removes the problem of fill disposal and provides an opportunity for restoration of the quarry site.There is a compatibility between quarrying and cleanfilling because at quarries:Truck routes are already established Neighbours are accustomed to the effects and appropriate buffer distances have been established Bringing fill into a site attracts aggregate sales and is very efficient. Fill originates from construction sites and ad-hoc excavations and therefore it is not surprising that sampling has shown the quality to be variable. Both Winstone and the Auckland Regional Council have surveyed undisturbed soils in the region to attempt to determine natural background levels of common contaminant substances. Comparison of these levels with delivered fill shows that a high proportion of delivered materials can be regarded as mildly contaminated. Therefore the term 'cleanfill' is, in the Auckland region at least, a misnomer and the term 'managed fill' has been adopted.Historically and presently the only control on quality of 'cleanfill' has been some visual inspection. This leaves the fill operator open to potential liability for creating a contaminated site. Implementation of controls at WinstoneÆs operations has progressed slowly, over some ten years. This is mainly due to the perception that mobility of contaminants within and out of the landfill will be very limited because of the near-neutral pH and abundance of clay minerals in the fill. The methods of control and results of environmental risk assessments at WinstoneÆs Puketutu Island Quarry will be briefly described.

Jan 1, 2002