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The problem of ventilating an advancing drive which finally reached 5,550 ft from the fresh air base in rock with virgin temperature of 83°F was solved economically by the use of two 15 h.p. electric fans forcing ventilating air through 281/2 in. dia. fiexible polythene tubing of wall thickness 0·010 in. The saving in cost over conventional metal duct was estimated to be £3· 24 per ft of drive.INTRODUCTIONAs described by Dutton (1965) and Newton (1965) the existing 1,480' ft level drive at the South Mine, Broken Hill, was extended in two stages. The first extension was 3,790 ft, the face then being 4,790 ft from the fresh air inlet. Later, after a vertical ventilation connection was made 1,000 ft back from the face, the drive was extended a further 4,550 ft. The rate of face advance in both stages was about 15 ft per day (3 shifts of 5 ft), 5 days per week. Drive size was 8 ft by 9 ft 6 in. high.The Mines Inspection Act of New South Wales requires 6 hr shifts (instead of the normal 7 in Broken Hill) to be worked if the wet bulb temperature exceeds 80°F. Virgin rock temperature on the 1,480 ft level was 83°F. Inlet air temperature varied with seasons from 58 to 72,oF wet bulb.To adequately ventilate the face, a flow of air of about 11,000 c.f.m. was thought to be necessary.Re-entry time was about 75 min, being governed by the 7 hr length of shift (3 shifts per day) and travelling time.Blasting was permitted only at the end of the shift, in accordance with local industrial restrictions.

Jan 1, 1965

By Matters C. W

THE following paper embodies the present practice and the results of past experience in the survey departments of two of the leading Broken Hill mines, the Central (Sulphide Corporation Ltd.) and the Broken Hill South S. M. Co. N. L.The authors intend to limit the scope of this paper to a consideration of office methods, as much has recently appeared in technical literature concerning field work, both surface and underground. Special reference may here be made to a valuable paper on 'Mine Surveying' by H W Gartrell, in Vol XIII of Transactions, in which the author gives considerable attention to field work. Moreover, much of the office work described in current literature is American, and sometimes not suited to local conditions, being ·often exceedingly elaborate and demanding a large staff of assistants. It is believed that the methods of recording information described in this paper are sufficiently simple and flexible to be adapted to most Australian mines. Brief acknowledgement must be made to the work done by Americans, who have raised mine surveying to the position of a separate profession, instead of being merely an unimportant branch of land surveying.

Jan 1, 1912

Observed mineral assemblages in the Mt. Lyell copper deposit can be correlated with phase equilibrium investigations in the systems Cu-Fe-S and Fe-Zn-S. The trend of crystallization (or paragenetic sequence) of the ores is reflected in a progressive increase in the Cu: Fe and metal: sulphur ratios of the assemblages. This trend agrees with the regional zoning of the district. Tentative relationships between the paragenetic sequence, sulphur vapour pressure, and temperature are presented graphically. The absence of a suitable geological thermometer prevents precise elucidation of the range of temperatures and pressures which existed during crystallization.INTRODUCTIONRecent phase equilibrium investigations of metal-sulphur systems at the Geophysical Laboratory, Washington, D.C. provide valuable information on the stability relations of a number of important sulphide minerals. This data, when applied to natural ore deposits, may be expected to clarify two special problems which confront the ore petrologist seeking to interpret observed data in terms of a particular physical and chemical environment of ore deposition. These two problems are the sequence of formation of sulphide minerals (commonly designated the paragenetic sequence) and an elucidation of the range of temperatures and pressures which existed during crystallization. The object of this paper is to make such an interpretation of the copper mineralization of the Mt. Lyell district, Queenstown, Tasmania.The following abbreviations are used in this paper:py = pyrite, cp = chalcopyrite, en = cubanite, bn = bornite,cc = chalcocite, cv = covellite, dg = digenite, id = idaite,po = pyrrhotite, v = sulphur vapour.GEOLOGICAL SETTING AND MINERALIZATIONThe general geology of the Mt. Lyell district is well known through the recent work of Wade and Solomon (1958). The host rocks are a series of quartz-chlorite-seri-...

Jan 1, 1963

Previous published papers by Fraser (1), Hey (2), and Stillwell (3), have given respectively, details of:-1. The practice in the pilot plant operated at Zeehan for the treatment of ores from the Rosebery field.2. The design, based largely on the experience gained at Zeehan, of the concentrator built at Rosebery.3. The nature of the orebodies of the zinc-lead lode at Rosebery.Changes and developments, at the Rosebery concentrator, since operations commenced, are now described with particular reference to recent practice.Three concentrates are produced, viz.: a copper, a lead, and a zinc concentrate. The current flow-sheet is shown in Fig. 1. Typical concentrate assays are...THE OREThe ore treated is derived from the Rosebery and Hercules Mines and is, milled in the ratio of, approximately, two parts of the former to one of the latter. The ores from the two mines may be considered as being similar in general character, although the Rosebery ore contains more pyrite. It is from this mine that any increased tonnage is expected. The ore is a mass of fine-grained, intimately associated sulphides, with practically no coarse...

Jan 1, 1949

THIS paper proposes to give a general description of the pumping and other machinery in use at the Thames Hauraki Pumping Station, situated on the Thames goldfields of the North Island, New Zealand. An idea of the general arrangement of the pumping engines and pumps can be obtained, together with a certain amount of detail, by reference to the illustrations. The history of the pump is rather interesting, and is as follows: -In 1894 the Government decided that a subsidy of £1 for £1up to an amoUllt not exceeding £25,000 be granted towards the erection of suitable machinery to exploit the Thames low levels.With a guarantee of such assistance a company was floated in London, with a capital of £300,000, to develop several properties at Thames. As the old Queen of Beauty Company had produced bullion worth £400,000 prior to closing down on account ofa breakdown to its pumping gear, their shaft was chosen as the site of the principal work. As soon as the company was floated, operations were commenced at the Queen of Beauty shaft, situated at the entrance of the Waio-Karaka Creek, and not more than about half a mile distant from the principal mines on the field.

Jan 1, 1912

By Lees M. G, Vitnell B. W

The post-war need to increase coal production promoted an intensive drilling campaign. Ineffectiveness in core recovery inclined the coal industry towards percussion drilling rather than diamond drilling. The Joint Coal Board, recognising the greater potential of core drilling, has actively encouraged improvement in techniques and equipment. One outstanding need was a barrel which, over and above other improvements being achieved, would permit recovered core to be examined before it had been subjected to the increased fragmentation and displacement which to date has been inevitable except in core which has been drilled in solid sticks û as New South Wales coal rarely can be drilled. In conjunction with Triefus Pty Ltd a barrel with a split inner tube has now been evolved, as a result of which, core can be more accurately logged, division in to lengths for analysis more aptly made, any core loss more reasonably allocated to appropriate plies, and a greater percentage of core recovered û of the order 95 per cent and more. The one half of the split inner tube is lifted from the other and the logging completed before the core is disturbed.

Jan 1, 1957

When xanthates or dithiophosphates are used as collectors in sulphide ore flotation, adsorbed species may be identified by gas chromatography of the volatile products formed during low temperature pyrolysis. For collector additions ,as low as 20 g/tonne of ore, pyrolysis of the flotation products usually gives' an olefin directly related to the particular xanthate or Aerofloat reagent used. The method is able to provide valuable qualitative and quantitative data relating to the extent of collector adsorption and the resulting changes in the hydrophilic or hydrophobic nature of the mineral surface.

Jan 1, 1974

By J E. Nethery

At the Red Dome and Mungana deposits in north Queensland, Australia, it is proposed that mineralisation and alteration developed as a 'telescoped' overprinting continuum, ranging in style from hypothermal to epithermal, reflecting the major changes that developed in the regional setting over the period circa 325 - 290 Ma. Regional assessment suggests that this also applies to many other precious and base metal deposits within a 40 km length of the host Siluro-Devonian Chillagoe Formation.   A ten stage paragenetic sequence of structural preparation, multi phase intrusion and associated mineralisation, alteration and brecciation is postulated for the Chillagoe district.

Jan 1, 1995

The case study has identified and characterised additional subsidence arising from longwall mining above or under existing longwall goaf. It suggests that the magnitude, mechanisms and prediction methods for such additional subsidence are different between the two mining configurations. This paper presents a proposed method to predict maximum vertical subsidence due to longwall mining under existing longwall goaf. It suggests that, unless different results from further new cases become available, the findings presented in this article, including the aforementioned prediction method, be applicable to the majority of sites in New South Wales, where multi-seam longwall mining is to take place. This article also presents an important concept of 'overburden modification' due to multi-seam mining. A causal relationship between the above-mentioned additional subsidence and 'overburden modification' has been identified as a result of the case studies. Further investigations into the physical processes that cause such overburden modification will be fundamental to the understanding and management of multi-seam subsidence.

Nov 25, 2010

By A Giblett, T J. Napier-Munn

This paper presents the results of a test program evaluating the impact of sample mass on the precision of Stage 1 gravity recoverable gold (GRG) test results. Four ore types ranging from low to high GRG contents were the focus of testing. A method to predict the influence of sample mass on the confidence limits of the Stage 1 GRG test result is demonstrated. The results suggest that although small samples tend to overestimate Stage 1 GRG in samples with low gravity gold values due to higher mass pull to concentrate, such samples can give acceptable estimates of the Stage 1 GRG content with focussed sample treatment protocols.CITATION:Giblett, A and Napier-Munn, T J, 2015. Measuring the influence of sample size on the precision and accuracy of gravity gold estimation, in Proceedings MetPlant 2015, pp 367–372 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

The application of biogeochemical methods in mineral exploration in semi-arid to arid environments in Western Australia has been investigated in an area near Norseman.The study involved a comparison of trace element characteristics of rock, soil and plants in the vicinity of the Pioneer BB prospect, where nickel-iron sulphide mineralization occurs in a "greenstone" sequence of ultrabasic, basic and sedimentary rocks.Analyses of unweathered and partly weathered rock from diamond drill cores show the ultrabasic rock to be highly variable with respect to Ni, Cu, Co, Zn and Mn.Samples of weathered bedrock and overlying soil were analysed for total trace element contents and for the trace elements associated with secondary iron and manganese oxides. Approximately 30 per cent of the total nickel content of the weathered basic rock is associated with secondary iron and manganese oxides, compared with approximately 15 per cent in the weathered ultrabasic rock.The soil has a sufficient residual content to provide a reliable indication of the chemistry of the underlying rock. Total trace element analyses of the -89 mesh fraction show strong anomalies for nickel and copper over the mineralized zone. Important amounts of nickel, cobalt and, to a lesser extent, copper are apparently associated with secondary iron and manganese oxides in the soil.Melaleuca sheathiana (tea tree) has been used to study the relationship between soil and plant chemistry. No strong relationship between plant and rock type was observed. Analyses were made of leaves, twigs, wood, bark and roots, and all plant organs were found to have anomalous nickel and copper contents near the mineralized zone. Leaves were found to give the best contrast in the anomalous area and to show fewer erratic values than other organs. It is concluded that the uptake of trace elements by tea tree is low in the semi-arid to arid environment of Western Australia, but that analyses of the plants do reflect the presence of mineralization.

Jan 1, 1973

By N Clarke, A Barros

Preconcentration of run-of-mine subgrade and marginal ore by screening has the potential to substantially improve the economics of mining, particularly for large, low-grade orebodies, and to reduce environmental impacts. It has recently been the subject of a major research effort by a joint public-private research body, CRCORE. Yet despite this, there appears to have been only one fully commercial installation, at Bougainville Copper Limited in the late 1980s. Two reasons for the limited application are that not all ores have suitable properties and the economics of all pre-concentration processes on low-grade materials are highly sensitive to the precise balance of mass and value recovery and to the pre-concentration process cost, including materials handling. These factors make it imperative to have good test data on the process response of feedstock across the orebody. Collecting that data presents major challenges, which differ for green and brownfields operations. This paper first discusses the approach to preliminary evaluation developed by CRCORE, which relies on testing of coarse rejects or drill chips available from exploration drilling programs. This method is an efficient first step in evaluating an orebody which is deemed geologically to be potentially amenable to screen upgrading, but it does have limitations and must be followed by larger scale work. A suite of methods have been developed by the authors as a result of test work since the 1990s on several projects, supplemented by published data, which aim to provide statistically robust data at lower cost than large scale bulk sampling tests. For greenfields projects, the upgrade response measured on material crushed to -53 mm has been found to correlate closely with ROM ore, with no scale-up required for material with upgrade responses in the range of commercial interest. Large diameter whole drill core, such as PQ, is expected to be suitable for this method. As drilling such core is costly, the aim should be to establish relationships between upgrade performance and proxy measurements such as multi-element chemical or hyperspectral analyses. This approach was successful at the Gramalote gold project in Colombia. The method is not applicable for ores with thick vein material comparable with the crush size, but such material is not suitable for upgrading by screening and would be eliminated by the preliminary testing. For brownfields projects where blasted material can be sampled, the upgrade response can be accurately measured by sampling only the finer fraction of the ore, selecting a top size which represents 30–50 per cent or more of the ROM size distribution. This is likely to be between 50 and 100 mm. The much finer size compared with the full ROM ore greatly reduces the sample mass required to achieve a given intrinsic sampling error and enables sample preparation to be undertaken with large-scale laboratory equipment rather than mobile crushing plant. The accuracy of the method can be improved by measuring the approximate mass of oversize rejected during sampling. Some ores do show a systematic deviation from the assumed model fit which results in this method slightly underestimating the upgrade response, and it would therefore still be recommended to take one or two full bulk samples to confirm results before a final investment decision.

Aug 24, 2022

I have chosen this subject in view of the fact that, while there are many and ample opportuuities of getting reliable assays made, there are but few who are in a position to obtain reliable data on the sampling of minerals and metals my long experience at Port Pirie, where, for five years, I had charge of the Refining and Sampling Mill, showed me how important it was that a correct sample should be taken.Weighing; This, to the ordinary layman, seems so simple that no expert knowledge is needed, but in actual practice there are hundreds of pounds to be lost by the lack of knowledge in this department.(1.) There is the matter of weighing in large or small quantities.(2.) The class of weighing machine used.(3.) The accuracy of weights used.We all know that, say, 1000 tons of ore cannot be weighed in one parcel; but the fewer the weighings the less loss to the seller (and usually wishes it weighed in small lots carefully) for it is a well known fact that the most sensitive scales take a certain weight to show distinctly the indication of the balance, or, in other words, what is known as "the pull of the scales." As for instance, 1000 tons weighed in lots of 1 c. each, taking the pull of the scale as being equal to 1 lb., would give a result of 9 tons loss to tbe seller, and as most of the ore sent to Customs works is worth 5. -£20 per ton-this would mean £180 loss to the careful man.

Jan 1, 1901

By Gale D. C, Giles D. E, James Parker A

A zinc-lead-iron sulphide concentrate from McArthur River can be leached at atmospheric pressure in aqueous solutions with HCI, FeCl3, CuCI2, HCl/02 HC1/02/ CuCI2, Cl2, and CI2/CuCI2 to extract >98 per cent zinc, >90 per cent silver, and <15 per cent iron in 1-7 h at 95°. Galena is more reactive than sphalerite and is converted to lead chloride. Except for leaching with HCI, elemental sulphur is the the main by-product of the leach with little or no sulphate ion detected. The rates and products of these reactions are compared. It is recommended that aqueous slurries of the concentrate (50 per cent w/v) are leached at atmospheric pressure with Cl2 in the presence of copper(II) chloride, which accelerates the extraction of zinc. Hydrochloric acid is a by-product which is consumed bYJeaction with fresh concentrate in air at 60°. Copper is subsequently stripped from the leach solution and recycled by reaction with fresh concentrate at 100°. The separation, recovery, and electrolysis of zinc and lead chloride is outlined since this process would produce Cl2 gas which can be recycled and used directly in the leaching stage.

Jan 1, 1976

By Sneddon N

In November, 1975, Aberdare North colliery was sealed at the surface to extinguish an open fire underground.The fire had developed from a spontaneous heating in one of the open goaf areas of the mine.The mine was re-entered with normal ventilation methods following the isolation of the working district containing the fire. The isolation was accomplished by remotely sealing the open roadways with lly ash emplaced through boreholes from the surface. A subsequent re-entry operation similarly closed the roadways close to the fire and enabled the re-opening of the sealed district.Most of the mine and the underground equipment was recovered after clearing of numerous falls and production recommenced on 25th October, 1976.

Jan 1, 1978

By L Matthews, D O’Dea, P C Hayes, J Manuel, B Monaghan, T Honeyands, D Pinson, J Leedham

Many different approaches have been used in the past to characterise iron ore sinter mineralogy to predict sinter quality and elucidate the impacts of iron ore characteristics and process variables on the mechanisms of sintering. Characterisation techniques include optical image analysis and point counting, X-ray diffraction and scanning electron microscopy. Each technique has its advantages and disadvantages depending on the objectives of the measurement. It is generally acknowledged that silicoferrite of calcium and aluminium (SFCA) is very important to the quality of the sinter produced; however, strict definitions of the phases and textures of SFCA are not generally agreed. This paper summarises the state-of-the-art in sinter characterisation applied in Australia by both academics and industrial researchers. The results from various techniques are compared and the relationships between the measurement results are discussed.CITATION:Honeyands, T, Manuel, J, Matthews, L, O’Dea, D, Pinson, D, Leedham, J, Monaghan, B, Li, H, Chen, J, Hayes, P C, Donskoi, E and Pownceby, M I, 2017. Characterising the mineralogy of iron ore sinters – state-of-the-art in Australia, in Proceedings Iron Ore 2017, pp 49–60 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

The importance of the Broken Hill mining field may be gauged from the fact that since the discovery of the ore-body in 1883, till the end of 1931, approximately 43,000,000 tons of ore have been raised.The lode covers a length of 31 miles, and in places is upwards of 300 ft. in width. The ore, as at present mined, consists of an intimately blended mixture of lead and zinc sulphides with silver and gangue minerals.Structurally the lode conveys the impression of a huge longitudinal arch (when viewed from the east or west), having its apex or crown near the centre of the field, in the leases of the Broken, Hill Proprietary Co. Ltd., where the lode outcropped at the surface.The minimum depth of the lode in the Proprietary mine was some 500 ft. from the surface, but huge undulations, having an average pitch of 45°, carry the extensions of the arch gradually deeper, to those places where active stoping operations are now in progress in the workings of the North mine at one extremity, and the South and Zinc Corporation mines at the other. The depth of the lode from the surface, as exposed at present, is approximately 1700 ft. at these extremities.The structure and physical character of the ore-body, and its containing walls, are so complex and varied that almost every type of mining problem is met with.

Jan 1, 1932

By K S. Fisher, J D. Pease

The installation of the George Fisher flowsheet in the lead/zinc concentrator at Mount Isa Mines Limited has recently been completed. The George Fisher flowsheet involved moving flotation capacity from the lead circuit to the zinc circuit and changes in zinc circuitry, changes in the reagent regime and increased regrinding capacity, using IsaMills, to regrind some streams to 80 per cent passing seven microns. The project was highly successful, delivering a five per cent increase in zinc recovery within a fortnight of commissioning. The George Fisher flowsheet was developed over six years. Laboratory work built upon the knowledge gained from investigating and processing the Mount Isa and Hilton orebodies. The engineering design and construction for the brownfield expansion of the existing lead/zinc concentrator had significant involvement from the operational, maintenance and technical personnel. Experienced personnel were seconded from the concentrator to the design and construction groups to ensure smooth integration of the new flowsheet into the existing concentrator with minimum downtime, and maximising the reuse of existing equipment. The combination of thorough design, good project integration with operations, and a good commissioning plan allowed almost immediate delivery of project gains. The project was highly successful, the full design improvements were achieved within two weeks, allowing the focus to move to developing future improvements.

Jan 1, 2000

Sedimentary pyrites from Tasmania have Se contents that are high for it province showing no overall Se enrichment. Sulphides from Devonian granitic rocks, and related cassiterite-sulphide deposits, Sn-Wand PbZn-Ag fissure veins have similar and relatively low Se contents, and pyrites from Devonian gold-quartz veins have very low Se contents. The high concentrations of Se at Mount Lyell are consistent with enrichment in pyritic Cu deposits in volcanic rocks elsewhere, and the dispersion of Se is consistent with a surface volcanic origin for several of the orebodies. In contrast, sulphides from Cambrian volcanic rocks and associated granitic rocks, and from the Rosebery and Hercules pyritic PbZn deposits, also believed to be of volcanic origin, are impoverished in Se.In the Mount Bischoff cassiterite-sulphide deposits there is no relationship between Se content of sulphides and temperature of formation as indicated by fluid inclusion studies, and sulphides from Devonian ores with different temperatures of formation have similar Se contents.The Se content of Tasmanian sulphides appears to be an unsatisfactory discriminant of their genesis and temperature of formation but in volcanic terrains may be a useful pathfinder for Cu concentrations.

Jan 1, 1969

In the course of work being carried out in the Lubricants and Bearings Section of the Council lor Scientific and Industrial Research on the production of copper4ead 'bearings for 'use in aircraft, it has been found necessary to develop special metallographic methods. For proper control of the production of steel-backed copper-lead bearings it is necessary to adhere to rigidly controlled conditions, and it is essential that a method of examination be adopted which will readily detect actual defects or any variations in quality. Some defects can be observed with the naked eye, whilst others are detected by radiographic examination. This latter method is invaluable as a rapid, reliable test in the production of aircraft bearings, but it is necessary to observe the structure of the alloys under the microscope, both to be able to interpret the radiograph correctly and to determine what has occurred to the metal during and after solidification. The use of a sound metallographic technique is'particularly important in developmental work and research connected with these bearings.Polishing TechniqueCopper and lead are practically immiscible in the solid state, but whilst they are miscible only in certain limited proportions in the liquid state; consequently "alloys" of copper and lead consist of a mixture of the constituent metals. The metallographic difficulties are obvious. Copper is a relatively tough metal, although it readily scratches, whilst lead is extremely soft and easily deformed. It wouId be expected if any normal polishing technique were applied that the lead would be readily torn out of the surface being prepared, and, in addition, that the lead would tarnish very easily.Grange(2) has described a method by which these difficulties can be overcome. The method involves an etch-polish procedure using "chrome regia" as an etchant for the copper. The chrome regia was a solution of chromium trioxide and hydrochloric acid in water. This type of etchant has been adopted, but it was found necessary to make certain changes.The method now adopted in this laboratory is as follows: The specimen (which is usually mounted in bakelite) is wet ground in a series of successively finer Hydro-Durexsil emery papers down to 60.0· grit paper.The specimen is then etched in the chrome regis, etchant (the composition of this etchant will pe discussed later) for approximately five seconds.Most efficient etching is obtained by swabbing the surface of the specimen...

Jan 1, 1944