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A study of literature on the epidiorite dykes which transgress the Broken Hill lode and its wall rocks reveals a considerable diversity of thought regarding the time of emplacement of such dykes. In this paper it is deduced that the epidiorite dykes were formed at a late stage and were probably post-ore. Detailed mapping, sampling, and correlation of data from over 100 exposures substantiates this deduction. Physical disruption of the epidiorite dykes is indicated and some interaction of the epidiorite and ore at the time of intrusion is inferred.Further petrological study may confirm this.

Jan 1, 1968

Study on the Mineral Processing Technology of Low-Grade Refractory Lead-Zinc Oxide Ores Containing Argillaceous and Carbonated Gangue in Yunnan

Sep 13, 2010

By Swayn G. P, Floyd J. M

BHAS, together with the G.K. Williams Laboratory, and Ausmelt Pty. Ltd., has examined a number of possible alternatives to conventional silver cupellation in gas fired reverberatory furnaces. Of these alternatives, a Sirosmelt furnace was preferred for both technical and economic reasons. Small scale work on Sirosmelt processes was carried out at the G.K. Williams Laboratory at Melbourne University in 1985/86. Pilot scale work was carried out at the Ausmelt plant in Melbourne in July 1987. Board approval for construction of a full size plant was received in October, 1988, and construction of the plant is currently underway. The plant is expected to provide significant savings in operating costs and silver inventory. Hygiene around the furnace should also be greatly improved. An increase in cupellation rate of at least ten times is expected, compared with the conventional reverberatory furnace.

Jan 1, 1989

By C OÆKeefe, A Thomas

Boom time in the mining industry has presented mill operators with several unique challenges including the need for increased throughput while being constrained by a shortage of skilled labour and aging capital equipment. New instrumentation technology that provides reduced installation costs; no process down time for installation; and reduced maintenance costs and labour requirements; has been introduced to address the labour situation while maintaining production. This new tech- nology also enabled more accurate and reliable process measurements thus providing the capability for operators to maximise throughput with their existing capital equipment. This passive SONAR based technology can accurately measure the volumetric flow rate of single phase and multiphase fluids as well as the amount of air entrained within slurries. This is accomplished in a non-invasive manner. This paper will describe the principle of operation as well as the application of the technology to critical minerals processing applications. Included will be operational examples comparing the SONAR measurement performance to traditional measurement techniques. These examples will include hydrocylone feed flow, flotation concentrate flow, and slurry streams containing magnetic ores. Actual plant data will be presented as well as a discussion on the operational advantages such a measurement capability.Also described will be the power of the technology platform to provide novel process monitoring and control capabilities such as pipeline sand-out prevention and pipeline acoustic monitoring.

Jan 1, 2009

THE object of the present paper is to give a brief description of the metallurgical process followed by the Grand Junction Co, and the results obtained therefrom. All figures quoted are from the actual working of the plant over a period of six months from January to June, 1910. The short ton of 2000 lb. is used by the company. Its gold is valued at 84s. per oz. fine, silver at 2s. per oz. fine. The ore consists essentially of a gangue of quartz and calcite, with 8 to 10%sulphide-pyrite, sphalerite, galena, chalcopyrite, and traces of arsenic and antimony. The colmtry-rock is a highlyaltered dacite. Small stringers of highly-mineralized ore penetrate the footwall of some of the lodes, forming a valuable stockwerk up to 3 ft. in thickness. In stoping, this is mined with the well defined lode, thus bringing into the mill at times a considerable quantity of hard country-rock. The gold exists in an exceedingly fine state of division, consequently rendering it necessary to grind very fine to obtain a satisfactory extraction.

Jan 1, 1912

The distribution or the userul minerals or Tasmania is so closely connected with the geological structure of the island that it will be convenient to briefly recapitulate the principal ract or its geological history, before describing the ore and other deposits. In many cases these present features which are very puzzling in the absence of knowledge of the structure of the districts in which they are found and in all cases it is of benefit to mining engineers to be acquainted with the main facts of the geological·history of the regions in which they have to carry on operations. Moreover, in speculating as to the origin of lodes and other deposits, we have constantly to rerer to the crumplings or the earth's crust by mountain-making movements, and to the igneous rocks which have been thrust throngh the other strata, to explain the origin or the lode fissures, and this discussion cannot be carried on without knowledge of local geology.The oldest rock yet met with in Tasmania are of Archooan age, and consist of highly crystalline quartzites and micaceous schist. They are most extensively developed towards the western side ot the island, forming a belt parallel to the West Coast from South-West Cape to Cradle fountain; but they also crop out here and there to the west and northward of this belt, where the covering strata or later age have been denuded away. Though not seen in situ in the eastern part of the colony, the abundance or pebbles derived from this formation in the conglomerates of the coal measures shows that it must in those day have formed land surfaces there also, and makes it likely that the archooan strata exist at no great depth: below many of the beds of later age now occupying the surface. Lying unconfortably upon these highly metamorphic strata we find next an extensive series of subcrystalline metamorphic conglomerates, grits, sandstones, slates, and limestones,of Cambro-Silurian age. These are well seen in the Gordou River Basin, along the West Coast Range, aloug the North Coast, and in the goldfields of the north-eastern portion of the colony. They are much broken by later intrusive rocks, and covered by younger rormations, but the series is spread more or less over the whole island.

By Y S. Zhang

Natural phenomena and human engineering construction activities had great influence on the geosciences space. Natural disasters, particularly mine disaster and other geological disasters happened frequently, which brought great losses both in people’s lives and economics, therefore, to explore the essential causes and mechanisms of disaster by some useful approaches is the most important step in mine disaster prevention. In a variety of methods, building an aground-underground seamlessly integrated model, and then analysing the formation and development mechanism of mining disaster based on this model is a useful way. In this paper, we studied an aground-underground seamlessly Integrated modelling method, and correspondingly given an aground-underground seamlessly integrated 3D spatial model, CSG+CD-TIN+GTP-TTS, by which we can carry out analysis of surface subsidence and underground laneway distortion efficiently, finally preliminary applications verified the effectiveness of this method.

Nov 22, 2011

Eco-Efficient Gravity Separation Solutions in India Sustainable development and social responsibility issues are a principal aspect of mineral processing operations around the world. With the need for more environmentally effective technologies, some gravity separation systems have provided eco-efficient mineral processing solutions in places where it is not otherwise viable because of lack of fresh water or for other environmental reasons. Advanced spiral separation technologies developed in Australia offer a cost effective and environmentally viable way to process minerals. In particular, we review recent case studies of spiral plants commissioned in India where environmentally sustainable solutions to design problems included the use of spirals operated with sea water and the use of high capacity (HC) spirals to provide low consumption of energy and materials and a reduced plant footprint. This paper evaluates the performance of various spiral plants in India and how critical environmental issues which affect the overall viability of wet concentrating processes where resolved.

Sep 13, 2010

Mineral exploration and development can have a significant impact on the environment and local communities, in some circumstances extending well beyond the mine site. Poor environmental performance and consequent social impacts by some companies have affected the reputation of the whole industry to the extent that the principal public concern about mining is its impact on the environment. This is consistent with public attitudes about other major natural resource sectors such as forestry and commercial fishing. Traditionally the community has relied on governments to set the benchmark for acceptable environmental and social performance through establishing and revising regulations governing the mining industry. This however assumes that regulations keep pace with community expectations. It also does not take into account those circumstances where governments can have conflicting roles as both watchdog and project partner. Government regulations and industry self-regulation are not in of themselves sufficient for the minerals sector to demonstrate that it has adequately addressed environmental and social issues associated with the sector. For the minerals sector to improve its reputation it must first improve its environmental and social performance. To do this requires the sector to operate to acceptable standards of environmental and social performance and for the sector to be able to credibly communicate this to its stakeholders such as investors, non-government organisations (NGOs), customers, staff, regulators and local communities. Independent third party certification of environmental and social performance (æcertificationÆ), already operational in forest and fisheries management, is proposed as a mechanism to enable the minerals sector to achieve this. World Wide Fund for Nature (WWF) and industry partners will be collaborating in a project to ascertain the applicability of æcertificationÆ to the minerals sector. A number of economic, social and environmental benefits are identified that could accrue should mining companies be able to differentiate themselves on the basis of environmental and social performance, an attribute evident in æcertificationÆ schemes. External audiences are seeking increasing levels of information and data on environmental and social performance of mining companies, be it local communities, investors, financial institutions or NGOs. Environmental and social reporting should be a key communications device that stakeholders can rely on as a reliable, credible source of information on environmental and social performance. WWFÆs contribution to the debate about environmental and social reporting has been to develop a process to assess the quality of environmental and social reports against reporting ingredients which WWF believe are important if a report is to be an accurate reflection of the reporting entitiesÆ environmental and social performance.

Jan 1, 2002

ABSTRACTOperations Research and associated techniques have wide application in the Mining Industry and have been used in Mount Isa since 1961.Typical of the projects undertaken by the OperatIons Research staff are1. the development of a complex computer programme for use in economic evaluation of mineral deposits,2. development of a production scheduling and control system for a complex mining operation,3. SImulatIon of a metallurgical plant operation to test the adequacy of design specifications and4. analysis of vehicular accident data to valuate alternative courses of insurance action.

Jan 1, 1968

By T Walsh, S R. Mudnuru

The development of lithium-ion batteries, coupled with the global trend towards electrification of transportation, has led to a dramatic increase in the demand for lithium. The production of lithium from hard rock ores is increasing, and flotation has proved to be an effective means for the beneficiation of many pegmatitic lithium ores. Clariant Mining Solutions has developed a range of novel collectors for the flotation of spodumene and other lithium ores, and this paper presents examples of some of the most recent developments. Fatty acids are the typical collectors for lithium flotation, however the grade and recovery achieved with these collectors is often below the desired level. There are also some significant drawbacks associated with the use of fatty acid collectors, such as the formation of calcium soaps which give rise to filtration problems and the need for acid washing. Several FLOTINOR products have been developed as alternatives to fatty acids. These products offer equivalent or better metallurgical performance at significantly lower dosages than fatty acids. This offers benefits to the flotation circuit as well as potentially reducing the issues associated with downstream processing of the concentrate.

Aug 24, 2022

By G C. Sen

All mining and quarrying operations that employ blasting to fragment and move broken ground have a price to pay for æby-productsÆ such as vibration and noise. These æby-productsÆ cannot be eliminated but they can be controlled and modern blasting techniques have improved to the point that excessive environmental restrictions can be adhered to whilst maintaining acceptable production rates and quality. Accurate measurement is the key to control, and as the environmental limits are becoming tighter, the proper way to measure vibrations from blasting operations becomes an integral part of the mining or quarrying operations. The basic vibration monitoring system consists of a primary sensor connected to a data logger and computer software for the analysis of the signal received and recorded. Currently, as with all fields of measurement, much improvement has occurred over the past decade, and electronic devices are much more accurate and reliable. Data analysis has also improved considerably with the computing power that is available to field operatives today. Mounting the primary sensor has been often overlooked in supposed æstandardsÆ with procedures such as double sided tape, resting on a flat surface provided the vibration level is less than a given amount. But if it is worth going to the expense of the monitoring equipment and manpower, surely it is worth a little extra effort to ensure the primary sensor is coupled to the ground effectively. The primary sensor must move with the ground and measure this movement; so if the primary sensor is allowed to move without respect to the ground (ie poor coupling to the ground) then a false record of the physical event will be measured. This scenario can easily be a practical reality if the primary sensor coupling method to the ground is not effective. In this study a number of mounting methods were fabricated and connected to similar data monitors and a series of ænormalÆ production blasts were used as the vibration source. These mounting devices were measured against an in-house procedure (the æstandardÆ) and the relative merits compared. A laboratory investigation was also carried out to look at the physical parameters of the æsoil and their effect on vibration attenuation of the in-house standard method.

Jan 1, 1999

The development of Western Mining Corporation's first commercial gold heap leaching operation is described. The laboratory testwork requirements for determining the amenability of ore to heap leaching techniques is discussed. Heap construction and operating practices are described; and production statistics and operating parameters are presented. It is shown that for a specific low grade gold ore a treatment cost optimization can be performed. Taking cognizance of the ore grade, percentage gold recovery, operating costs, and the gold sale price, it can be determined whether Carbon-In-Pulp (C-I-P) or Heap Leaching should be employed as the extraction process. The examples presented in this paper refer specifically to Kambalda and should not be used in themselves as generalities.

Jan 1, 1987

An Investigation into the Flotation Behaviour of Pyrrhotite Present in the Merensky Orebody

Sep 13, 2010

By C Johnstone

Project management is not a task to be undertaken lightly. Mining projects generally present even more challenges due to ChinaÆs remoteness and complexity. Having experiences in project management in the West is certainly an asset, but China can present the uninitiated with any number of headaches. To undertake a project there can have many problems that are unique to China. For the last 15 years, China has seen an increasing number of foreign capital investment projects in the mining industry. Practices involved in mining project development have experienced/are experiencing an evolution. Since 1996, Sino Gold Mining Ltd has delivered three mines in China, ie Jianchaling Gold Mine, Jinfeng Gold Mine and White Mountain Gold Mine. Through the work, Sino Gold has established a solid knowledge base and a capable and skilful workforce in effectively undertaking mining projects in China. This paper is concerned with the experiences accumulated so far by Sino Gold in project management in China. An overall review is conducted regarding the reform of the mining project development in China. Opportunities and challenges are highlighted within the political, economic and culture context. Brief summaries of the development of the three gold mines are presented.

Jan 1, 2009

By W B. Edgar, I M. Platten, C A. J Towsey, B W. Cuffley

The evaluation of historical goldfields has been common over the past 15 years, reflecting changing economic conditions, improvements in knowledge and technology and lack of greenfield sites. Many goldfields comprise narrow gold-quartz veins, which are structurally complex with an irregular distribution of gold, have variable geometry and architecture and display late deformational effects. The study of historical mine records can be an important tool during early and advanced project evaluation, since it contributes to understanding the orebody, exploration target size and setting expectations. Mine records include documents such as plans, sections, reports, news cuttings, production tabulations, etc. A major advantage for the modern explorer is the capability of computer modelling to display this data in 3D. Historical records can give the explorer substantial information on various deposit characteristics, not least grade and geological continuity, geometry and architecture, mineralogy, metallurgical properties, bulk density and ground conditions. From an evaluation perspective, historical records can be used to support a Mineral Resource estimate, though its application will depend upon the quality and quantity of the data and judgement of the Competent Person. Effectively used, historical records can reduce geological uncertainty and focus evaluation efforts û thus reducing project risk.

Jan 1, 2009

By N Elith

Coal is a valuable energy source in New Zealand and has been mined from the West Coast for over 100 years. Stockton Mine is New Zealand's largest opencast coal producer supplying around 1.5 Mt of hard coking and thermal coal to international markets annually. The Stockton Plateau forms an extensive, gently inclined dip slope on erosion resistant Lower Eocene Brunner Coal Measures unconformably overlying basement rocks. The dip slope rises 600 - 1000 masl, locally dissected by fault scarps and present-day fluvial systems, some of which are deeply incised. Within the Mt Augustus Mining Block overburden comprises of a 30 - 40 m thick sequence of fluviatile, coarse to granular coal measure sandstones. High quality coking coal is preserved as a gently dipping, 10 - 12 m thick seam. High and sometimes very steep cliffs of jointed overburden shape the skyline escarpment, above steep forested slopes and gullies. As mining has progressed at Mt Augustus individual coal blocks are progressively becoming more technically challenging. This paper outlines the scientific approach taken by Solid Energy International and mining contractors to carefully unlock many thousands of tons of coal whilst protecting nearby flora and fauna from the impacts of dislodged rock and other blasting side-effects. The strategy involved: an expert-driven onsite risk assessment,formulation of a management plan to manage impacts,conducting an in situ vibration research program, andanalysis of results and operational designs to eliminate potential environmental problems.

Jan 1, 2003

By R McCarthy, P Darvall

FerrAus Limited's Robertson Range and Davidson Creek iron ore projects are located on the far eastern margin of the Hamersley Province, approximately 100 km to the east of Newman, Western Australia. The deposits are primarily formed of bedded haematite-goethite-limonite mineralisation within the Marra Mamba Formation, comprising a total combined resource of 164 Mt at 58.6 per cent Fe. The deposits represent relatively new discoveries for the Hamersley Province. The potential for mineralisation at Robertson Range was identified by Rio Tinto Exploration in 2000, while Davidson Creek remained untested until 2007. One of the main reasons for this is that these deposits are almost exclusively concealed beneath Tertiary sediments and recent transported cover making them difficult targets for conventional, prospecting style exploration. Since commencing exploration in the project area, FerrAus has collected nearly 20 000 stations of gravity data within the Robertson Range and Davidson Creek project areas, with most of this data collected at a 50 100 m station spacing. Gravity has proven itself to be an effective technique at predicting the position of the target host stratigraphy and has been a key driver in the exploration for concealed iron ore deposits. However, there is not always a perfect correlation between the position of gravity anomalies and concealed ore. The response of deep haematite bodies may be masked by low-density cover rocks, while other dense lithologies may be the cause of gravity anomalies which appear similar to the Marra Mamba targets. Hence, effective use of the gravity data requires interpretation in a geologic context with an understanding of the capabilities and limitations of the technique.

Jan 1, 2009

By J Samosir, L Snyman

Northparkes was the first mine in Australia to use block cave mining method which relies on gravity and natural rock stresses to fragment and recover the ore. It was also the first hard rock mine to use hydraulic fracturing, in conjunction with CSIRO, to promote caving of E26 Lift 1. The technique was later used on E26 Lift 2 wedge and E48 prior to undercutting.Northparkes production is currently sourced from the E48 Lift 1 block cave mine and E26SLC. The E48 block cave contains economic ore to the north and south of the current cave footprint. To recover this ore the footprint has been extended on the north and south with two extraction drives and one extraction drive, respectively. Modelling of cavability above the additional drives indicated that the cave would not readily propagate to a sufficient height of draw to mobilise the ore and tended to arch over into the existing cave. To address the modelling results and to reduce the risk of the project, rock mass preconditioning was adopted.This fracturing campaign was performed from surface drill holes adjacent the subsidence zone angled to intersect the higher grade and higher elevation ore zones.Optical televiewer surveys, run prior to fracturing, picked intervals and fault zones to be avoided. Holes were resurveyed post-fracturing to detect newly created fractures and as a measure of success of the program.During fracturing operations water and gel fractures were run at varying depths and pumping pressure was logged for each fracture. The mine seismic system monitored significant events and dye in the fluids utilised for tracking water inflow locations during underground inspections.Towards the end of the project, guar fibres from gel were detected within the mill circuit and required treatment to resume optimum processing.CITATION:Webster, S, Snyman, L and Samosir, J, 2016. Preconditioning E48 cave extension adjacent to an active cave, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 471–478 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By S C. Dominy

Gravity amenable gold ores are those that after comminution produce liberated particles, composites and/or carriers that can be recovered by gravity separation means. Recovery depends upon mineralisation type and the comminution and concentration method used. Any in situ ore with more than 20 per cent of gold greater than 100 µm in size is likely to have a strong gravity recoverable component. A less traditional approach is where the gold is sulfide-locked and the gold carrier plus any liberated gold is recovered via continuous gravity recovery following fine crushing. Specific tests are undertaken to determine the level of gravity amenable gold within a deposit. The principal methodology is the gravity recoverable gold (GRG) test, which consists of three sequential liberation and recovery stages. For continuous gravity recovery (CGR), the sample is fed over a laboratory Wilfley table to simulate continuous recovery of the gold. Tails from the feed can be progressively re-ground and re-tabled to develop a grade-recovery curve. Primary geology and gold particle size-distribution have a strong effect on the mass of sample required to provide representative results for both tests. Where low-grade ore contains very coarse gold, substantially larger sample masses are required. Experience has shown that GRG and CGR values can vary throughout an orebody, particularly within different geological-grade domains. A testing regime must consider sample frequency and support.

Sep 5, 2011