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The Mount Isa mine in North West Queens- land produces a total of nearly 10 million t/yr from separate copper and silver lead zinc orebodies. Sampling information is mainly obtained from diamond drilling on 30 to 40 metre centers in both types of orebodies. For the copper orebodies the majority of the core is analysed for copper content using a non-destructive bulk analyser developed by the Australian Atomic Energy Commission. The diamond drill core in the silver lead zinc orebodies is usually sam- pled as sawn half core and assayed in the com- pany laboratory using a variety of methods dependent upon the level of metal content and/or the elements required. Underground development is sampled where additional information is required to improve the ore reserve estimate. The copper areas are sampled using a standard 2.0 m by 2.0 m chip sample of the wall. The chips are taken on a 250 mm spacing. Lead areas are sampled using a 100 mm wide by 4 mm deep channel over intervals determined by the area geologists. The massive, irregularly shaped copper ore bodies are mined as large sublevel open stopes and pillars. Ore reserve estimation on both a production unit and global scale is routinely carried out using a geostatistical system developed in-house and running on a Sperry 1100 mainframe computer. Copper grade, tonnes and the Kriging var- iance are estimated at points on a user defined grid. The Kriging program uses 10 m assay composites from diamond drill core and underground chip samples. One average (rela- tive) variogram is used throughout the main copper orebodies. The validity of using an average variogram was verified by the original geostatistical study undertaken in the late 1970's.

Jan 1, 1987

During the course of the major research in the Metallurgy Department of the University of Melbourne into the creep characteristics of lead and .its dilute alloys, it has been the practice to prepare the majority of test specimens from rolled strip. From time to time during the progress of the work, certain variables involved in. the rolling of the experimental ingots have been investigated. It is proposed to collect together in this paper the results of these experiments. Some general features relating to the type of deformation produced have been discussed in a previous paper.While it is admitted that the conditions prevailing through this work differ' in some respects from those of industrial rolling practice, it is felt that many of the factors investigated have an important practical significance. Some of the work described forms a continuation of the researches of R. S. Russell (2) , (3) , (4), into the recrystallization of various pure leads after deformation by rolling.MATERIALS USEDIn this work, a variety of "pure" leads and certain dilute alloys made from the purest of the basis leads have been studied. The compositions of the basis leads and the corres...

Jan 1, 1940

Development of aggregate resources for use in structural concrete has been encouraged in Japan to support infrastructure improvement and national land conservation. Natural aggregate is a valuable resource necessary for sound economic development, and its importance is growing. After completion of aggregate mining projects, planting and afforestation are implemented. But sandy soil in excavation sites is not optimum for the growth of vegetation, and many years are needed before forests are restored. Planting techniques should be improved to support efficient reforestation in a shorter period of time. For this purpose, problems hampering growth of vegetation must to be solved through application of physical and physicochemical techniques to ensure that the environment and the ecosystem will be conserved in project sites.

Dec 6, 2010

The Wamum and Idzan Creeks Prospect, located 79km W of Lae, Morobe Province, Papua New Guinea (PNG) was discovered by the exploration arm of Conzinc Riotinto of Australia Pty Ltd (CRAE). The detailed surface exploration and 11 vertical holes drilled by CRAE, combined with the recent work by Highlands Gold Limited, indicate the occurrence of porphyry copper-gold mineral- isation and associated alteration. The prospect occurs within andesitic volcanics of the Middle Miocene Langimar Beds. It is bounded by NE trending faults to the NW and SE. The alteration and mineral- isation is hosted in the andesitic tuffs adjacent to high level quartz diorite and hornblende diorite stocks. A NW trend to alteration and mineralisation is obvious in Wamum and Idzan Creeks. The main alteration type is propylitic with minor zones of potassic alteration. A late sericite-quartz-kaolinite-pyrite alteration overprinted the earlier alteration and mineralisation. Copper and gold mineralisation is related to a quartz-carbonate-chalcopyr-ite-pyrite (¦ bornite) vein stockwork and biotite ¦ K-feldspar alteration. The mineralisation system at Wamum and Idzan creeks is low in total sulphides. It is considered as a high- level fracture-controlled system with limited low grade Cu-Au mineralisation.

Jan 1, 1991

By S Morgan, D J. Bradshaw, S Schwarz

The characterisation of the flotation kinetic response in future mining deposits is important because the flotation response is affected by changes in ore mineralogy. Current methods for characterising the flotation response of different ore types, such as the JK floatability index test (JKFIT) methodology, require at least 10 kg of feed material. In geometallurgical applications, this material is taken from core samples. Core samples are generally obtained using specialised drills and are limited in nature. Thus, it would be beneficial to develop a laboratory technique that required less sample material but still characterised the flotation response of different ore types. The JK mineral separation index (JKMSi) is a small-scale flotation test that requires significantly less feed material (10 g of sample/data point). This study aims to investigate the JKMSi system kinetics and to validate this technique using the JKFIT proven methodology. The JKMSi flotation kinetics were manipulated by varying selected system parameters. The relationship between these parameters and mineral recovery was used to obtain floatability characteristics of the ore. For an ore sample containing chalcopyrite and pyrite, it was found that the chalcopyrite floatability parameters determined from both the JKMSi and JKFIT tests were of the same order of magnitude and the mass fractions of the fast, slow and non-floating components were similar. For pyrite, the floatability parameters were not of the same order of magnitude, but modifications to the test procedure have been identified, which may correct this.CITATION:Morgan, S, Bradshaw, D J and Schwarz, S, 2012. Julius Kruttschnitt Mineral Separation Index - Small-scale test to characterise the flotation response of an ore type, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 159-162 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

The Cowarra gold mine is at latitude 36°O'S. and longitude 149°19'E. which is roughly 20 miles north-north-east of Cooma.The deposit was· originally worked towards the end of the last century, but the presence of sulphides associated with the gold in the primary zone caused cessation of work when that zone was reached.GEOLOGY AND MINERALIZATIONThe principal country rocks are sandstones and shales of Silurian and Ordovician age, both very strongly folded with structural pitches ranging from a few degrees to almost vertical. The mine proper is within Silurian rocks and the main orebody (there are several minor parallel bodies) is developed within a shear striking approximately north, dipping approximately 70° east, and ranging in width from 2 ft to 15 ft but averaging about 4 ft.This shear is impregnated with quartz and sulphides with which the gold is associated. The predominant sulphide is pyrite though pyrrhotite is commonly present in quantity.Arsenopyrite and bornite are present in smaller amounts.Stillwell (1936, 1937a, 1937b, 1938, 1941) has published five mineragraphic reports on the ore.The various levels have been mapped in detail (Figs. 1-3) and the No. 2 level plan (Fig. 1) shows the general relationship of shearing, as now indicated by mineralization, and faulting. There is no apparent connection between the fold structures and mineralization.Fig. 3 is a longitudinal projection showing the distribution of gold expressed as inch-ounces. The estimation of...

Jan 1, 1965

By U JSger

The Westerschelde tunnel will be the first permanent road link between the Dutch regions of South Beveland and South Flanders. Two tunnel tubes, each 6.6 km long, will be driven using the shield tunnelling method. The difficult ground conditions and a water pressure of up to 6.5 bar make great demands on the design. This paper describes the problems and their solutions.

Jan 1, 1999

By C Spandler, S W. Richards G Rosenbaum, R J. Holm

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.The recent and active magmatic arcs of eastern Papua New Guinea (PNG) and the Solomon Islands are well endowed with sulfide mineralisation and include deposits such as Ladolam, Panguna and Solwara 1. The majority of the mineral systems in this belt are younger than four million years old, with some deposits remaining active to the present day as exemplified by active hydrothermal systems on the island of Lihir. The geodynamic setting that led to the formation of these deposits is still unresolved, with, for example, both the Pacific and Solomon Sea plates considered responsible for the formation of the Ladolam deposit on the island of Lihir under different models. In order to understand and characterise the formation of south-west Pacific mineral deposits, we must first reconstruct the complex geodynamic evolution of the region. New kinematic reconstructions show that while mineral systems in eastern PNG and the Solomon Islands are hosted within a single arc related to subduction at the New Britain and San Cristobal trenches, variable and discrete geodynamic settings exist within both the upper and lower plates throughout this region, which give rise to distinct mineralised corridors. Most notably, this region is host to: the Solwara 1 deposit, which occurs within a major transtensional corridor in the eastern Bismarck Sea the Ladolam deposit (Lihir), which is interpreted to have formed above but in relation to tearing of the subducting slab the Panguna deposit, which is related to structure in the subducting slab marginal to the actively spreading Woodlark Basin.An evaluation of the nature and variability of these diverse geodynamic settings through time can provide us with a better understanding of the relationship between the active south-west Pacific magmatic arcs and mineral deposit formation. It may also provide insights into the diverse array of deposit settings at ancient convergent margins, with applications in mineral prospectivity studies.CITATION:Holm, R J, Richards, S W, Rosenbaum, G and Spandler, C, 2015. Disparate tectonic settings for mineralisation in an active arc, eastern Papua New Guinea and the Solomon Islands, in Proceedings PACRIM 2015 Congress, pp 165–170 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By J E. Everett, K Jupp, T J. Howard

Precrusher stockpiles are designed principally as buffers to decouple the mining and processing operations. They are usually paddock dumped or dumped over a face to form fingers by dumping haul truckloads and reclaimed by front-end loader in an ad hoc manner. In addition, they are often not built and reclaimed to completion but continually added to and extracted from. While this design suits the mining process and is operationally simple, there can be little confidence in the grade of the ore that is fed to the crusher. This makes short-term grade control difficult and reconciliation back to the mine face imprecise. Well-designed and operated precrusher stockpiles can overcome these deficiencies.The different types of grade variability in mining are reviewed in this paper. The role of precrusher stockpiles in reducing short-term variability is discussed and their ineffectiveness in addressing long-term variability is highlighted. Their role in removing the serial correlation of the extracted ore is explained.Precrusher stockpiles carry out the four, at times competing, objectives of storing, buffering, blending and grade separation. Their actual design and operation result from a compromise between these four competing roles. These roles are explained in detail along with the advantages and disadvantages of the different types of precrusher stockpiles. The recommended blended-in blended-out stockpile (BIBO) design is discussed in detail. Matched pairs of BIBO stockpiles of limited tonnage built and reclaimed to completion retain the best knowledge of grade and facilitate the reconciliation process.Simulation studies have been carried out on BIBO stockpiles to understand the blending opportunities of the different options for building and reclaiming, and to identify the methods that achieve maximum blending. It was found that laying down rows in one direction and reclaiming across these rows gives the best blending. Matching the width of the reclaim face with the daily crushing requirements is also important. The length of the rows, and building in either one or two layers has little effect on the extent of blending.Appropriate design can provide a reasonable compromise between the four objectives.CITATION:Jupp, K, Howard, T J and Everett, J E, 2013. The role of precrusher stockpiling for grade control in mining, in Proceedings Iron Ore 2013 , pp 203-214 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By Player WP

The legislative operating environment, or the mineral regime, that a country has to offer is one of the key determinants that a company wanting to invest in an area takes into account in formulating its investment decision. The New Zealand Government recognises this and the importance of getting the regime right in order to provide for continuing investment in mineral exploration and mining in New Zealand. In recent years, the Government has given considerable attention to developing legislation which provides for investment to take place; for those making the investments to have a stable, fair and open investment environment with government intervention only when considered absolutely necessary because other approaches are not working; and for the people of New Zealand to know that investment must meet acceptable health and safety standards and have acceptable impact on the environment. Also of key importance is having a clearly defined mining regime which includes rules on how to obtain a permit and rules in respect of ongoing permit compliance, rights to develop a mineral resource and permit conditions (in particular, the royalty regime). In New Zealand, these matters will all be addressed in what are referred to as "minerals programmes".

Jan 1, 1995

Forecasting, particularly when applied to meaningful issues, is known irreverently as 'futurology'. There is quite a range of opinion ext.ant in the world when mineral resources are looked at. The opinions range from the doomsday view that there will be acute shortages of all essential commodities, to the optimistic outlook that new 'discoveries will prevent any possibility of shortages. The environment is, as yet, only studied locally and quite parochially; surprisingly there is little integration when considering the spatial atmosphere, the seas in depth and the earth's crust.

Jan 1, 1981

By T Sylow, A Correa De Araujo, M Gotelip Barbosa

ArcelorMittal is among the largest world’s producers of iron ore. With a geographically diversified portfolio of iron ore and coal assets, it is strategically positioned to serve the network of steel plants, as well as supply the external global market. ArcelorMittal Mining has a global portfolio of 14 iron ore operating units across Brazil, Bosnia, Canada, Kazakhstan, Liberia, Mexico, Ukraine and the United States. Iron ore products include concentrate for sintering and pelletising, pellets, directly shipped fines and lump ore. This paper presents an overview of ArcelorMittal iron ore mines including iron ore typologies and the annual production of each unit. It will also briefly discuss the processing required in order to obtain marketable products.CITATION:Gotelip Barbosa, M, Correa De Araujo, A and Sylow, T, 2017. Overview of ArcelorMittal mining operations and research and development, in Proceedings Iron Ore 2017, pp 161–116 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By G L. Boyd

Backfill applied to highwall mining is foreseen as a means to increase recovery of mineable coal to levels comparable with underground longwall mining. This paper describes the progress of research to demonstrate the role required of backfill to achieve real increases in coal recovered by highwall mining methods.

Jan 1, 1998

Throughout history, many of the world's achievements, conflicts and problems can be traced to the demand for minerals. With the rapid expansion of our industrialised society in recent years the demand for minerals has grown to such an extent that uncertainties about availability and cost have arisen, especially in the case of energy minerals.Minerals have acquired a new dimension for governments as the availability of these resources is interwoven with the ability of governments to achieve their developmental goals on national and international levels. Accordingly, the supply of minerals will increasingly be affected by social and political factors.

Jan 1, 1986

By Z Fu, E Topal, O Erten

"Mine waste rock management involving waste rock movement and placement, is a critical aspect in the planning of open pit mining operations, as the waste rock haulage cost can be the largest portion of the mine operating cost. The concept of sustainable development in the mining industry also encourages environmentally friendly waste dumps that have zero hazards to people and the surrounding environment. Therefore, a detailed waste management schedule must satisfy economic and environmental considerations. However, the available tools in the market cannot provide optimal waste dumping schedules to meet all these constraints. This paper introduces a user-friendly and automatic tool to optimise the waste dumping schedule, which minimises the haulage cost, and covers the encapsulation of reactive materials to minimise acid mine drainage problems. This tool has been developed by using a new mixed integer programming (MIP) mathematical model that considers both single-lift and multilift dumping scenarios. The application of the proposed tool on a data set collected from a gold mine shows that the multilift dumping scenario has provided a more flexible and economical waste dumping schedule than the single-lift scenario, and both scenarios satisfy environmental requirements.Citation:Fu, Z, Topal, E and Erten, O, 2016. A Modified Software Tool for Mine Waste Rock Dump Planning, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 229–242 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

The addition of a thallous salt to the cyanide leach of a calcined pyritic concentrate causes a marked increase in the rate of extraction of gold. This is due probably to the activation of passive gold by the thallous ions. Lead, bismuth, and mercury salts, which should produce a similar effect, fail to do so. It is postulated that this latter result, together with the reprecipitation of silver at low cyanide levels, is due to the presence of soluble sulphide.INTRODUCTIONThe work of Fink and Putnam (1950) showed that the rate of solution of gold in cyanide can be increased by the addition of small amounts of lead, bismuth, mercury, and thallium salts. Mills (1951), during a study of the electrochemistry of gold, with particular reference to cyanidation, was able to show that gold may become passive towards cyanide solution. The addition of lead or thallium salts prevented this passivity, although the action of lead was limited to the pH range 10 to 12. In a recent paper Cathro (1963) confirmed the findings of Mills, and presented results which showed that the addition of thallium to a cyanide leach of a calcine from Lake View and Star mine, Kalgoorlie, increased the rate of extraction of gold appreciably. In, this paper the use of thallium to prevent the gold becoming passive, and hence to decrease leaching time and cyanide consumption, is examined.EXPERIMENTALA series of leaching tests was carried out on a sample of Lake View and Star calcine, comprising calcined pyrite (about 70 per cent.) and siliceous gangue (about 30 per cent.) and containing 165 p.p.m. gold, 45 p.p.m. silver, 0·1...

Jan 1, 1964

By A Seneviratne, Y Li, N Udugampola, X Ai, B Li

LoRa (Long Range) is a low-power, long-range wireless communication technology that has gained significant research interest for its potential use in multi-hop linear wireless sensor networks (LWSNs) for underground mines. These networks deploy LoRa-enabled sensor nodes in underground mines, together with LoRa repeaters placed along mine tunnels to relay sensor data to a LoRa gateway, which connects to a backend network for application-level processing. Since the packets generated by sensor nodes farthest from the gateway have to hop through many repeaters, their probability of successfully reaching the gateway is significantly lower due to the higher chance of packet collisions compared to sensor nodes closer to the gateway, resulting in a lack of network fairness for the sensor nodes. In this paper, we first present an algorithm to improve the fairness of a LoRa LWSN by grouping neighbouring nodes and adjusting the number of packet re-transmissions and transmission intervals for each group. Then, we demonstrate that the fairness of a simulated LoRa LWSN can be improved by approximately 500 per cent by applying our algorithm. We verify our algorithm with network simulations under different network traffic levels and grouping strategies, obtaining fairness improvements in each scenario. Our algorithm and results will pave the way towards developing highly fair LWSNs for underground mining applications.

Sep 1, 2024

The Aberfoyle Tin Mine lies on a wide sloping bench about 2,000-2,500 ft. above sea level, at Rossarden, 14 miles north of Avoca, in north-eastern Tasmania. The quartz-cassiterite veins were discovered in 1916, but mining did not begin until 1926. Trenching revealed seven small tin-bearing veins within a width of 57 ft. of Palaeozoic slates and sandstones, and it was assumed that the mineralization extended beneath the adjacent cover of Permian strata, but the presence of the main vein system (the 26 Vein System) was not suspected until the Aberfoyle Fault was discovered late in 1928.The mine has now been developed on thirteen levels, to a depth of 1,350 ft. The lower limit of economic mineralization appears to lie at about the ll-level, which is 1,060 ft. vertically below the concealed outcrop of the main veins. Production of tin and tungsten concentrates began in 1932, and to date more than 550,000 tons of ore have been mined for a recovery of 8,856 tons of tin concentrates, and 3,056 tons of wolfram concentrates, valued at approximately £6,500,000.This paper reports part of an investigation undertaken by the Mineragraphic Investigations Section of C.S.I.R.O. to study the mineral composition of the ore in relation to the apparent failure of cassiterite and wolfram mineralization to extend below the present working limits of the mine, and was first issued as Mineragrapnic Report No. 639.GENERAL GEOLOGY:The deposit consists of a series of quartz veins in a northsouth trending sheeted zone, transecting folded slates and...

Jan 1, 1957

IN concentrating mills, where several millerals are recovered for realisation in more than one product, various systems are used to express the relative economic value of the work done, and, in the hope that it may prove of use to other operators, the writer will describe a system which, in his opinion, is more complete than any other that he has seen published.The controlling factor in all mill work must be based on the economic result represented by the greatest margin possible between the realizable value of the products and the cost of obtaining same.From a mill-man's point of view these are affected by the following factors:1. Metal contents of ore.2. Grade of products.3. Recoveries.4. Working costs.The grade of ore milled is usually outside the mill-man's control, but this may exercise a considerable influence on the grade of his products, metal recoveries, and revenue per ton of ore. Higher grades or recoveries may be obtained by using a more expensive process, or by additional grinding or reagents, and the economic comparison can only be arrived at by obtaining an analysis showing the monetary value of each variation within the possible limits.In the system to be described, the value of unit variations of metal contents of the ore, grade of products and recoveries are calculated in terms of a monetary unit per ton of ore with the returning charges ruling, and any suitable metal prices. To do this it is necessary to assume what, for convenience, is termed a "standard" set of results from the mill, preferably representing about average conditions, and having calculated the effect of unit...

Jan 1, 1931

By Robson W. D, Irwin D. A

In November, 1932, an investigation of silicosis was undertaken at the, McIntyre Porcupine Mine, Schumacher, Ont., atfer a discussion of the problem with Sir Frederick Banting and his, staff. As a result it was decided to carry on dusting experiments with animals at the mine in a manner that would duplicate as far as possible actual industrial conditions.At that time 50, guinea pigs were placed in the crusher nouse tunnel of the mill where a considerable quantity of fine dust, containing approximately 35 per cent., of free silica, was being constantly produced. These animals lived in this atmosphere for periods up to one year, and, while on autopsy large amounts of dust were found in the lungs, not a single case of silicosis had developed. These negative results suggested, among other things, that the mine gases might be a predisposing factor in the production of silicosis, and the results of this investigation led us to undertake the study of the hydrogen-ion concentration of the condensate of the atmosphere, both in the mine and in various sections of the mill.The C02 combining power of blood serum on a series of 400 miners was also studied at this time. While these results were inconclusive, the variation in the hydrogen-ion concentration of the condensate between the surface and underground atmospheres encouraged us to investigate the effect of neutral, weak acid and alkaline solutions on the solubility of silicious materials. Gye and Purdy were the first to point out that the chemical reaction and not the physical presence of silicious material was responsible for the production of the fibrosis in silicosis. This work was investigated by Gardner and Cummings who showed that the tissue reaction to quartz was definitely proportional to the size of the particle. They found that 1-3 micron particles of quartz produced an acute proliferative fibrotic response while the 10-12 micron particles produced only a foreign body reaction up to a period of three years. It is accepted that the dangerous silica particles retained by the lung are under 5 microns in diameter. We assumed that if the solubility of the silicious material retained in the lung could be reduced sufficiently by the addition of some non-toxic element or compound the usual fibrotic respohse would be modified. We found that the addition of certain compounds to silica would reduce its solubility in the beaker to a slight extent. But these compounds, when mixed with quartz...

Jan 1, 1945