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By Spark R. F

The copper deposits at Pernatty Lagoon are predominately djurleite-digenite bodies beneath the permanent water table, and chrysocolla-atacamite-malachite above the permanent water table. The minerals havebeen deposited as sheets, lobes, and pods in zones suggestive of permeability channels or permeability basius with respect to groundwater circulation.Pyrite is deposited in the form of framboids, which reflects its biogenic origin. Copper-iron sulphides deposit by replacement of pre-existent pyrite, and rarely by direct deposition. The latter mode of formation results in complex crustification bandings of chalcopyrite, bornite, sulphur rich bornites, digenite, and blue remaining covellites. The copper-iron sulphides appear to reequilibrate under constrained oxidation, resulting in an iron depletion and associated copper enrichment, the final product of which is a djurleite-digenite assemblage and associated with goethite. Where copper mineralization/ host rock relationships have rendered the rocks entirely impermeable to post ore groundwater movement, then the copper-iron sulphides are preserved as the ore assemblages.Minor and trace minerals observed include sphalerite, carrollite, galena, wittichenite, and possibly tetrahedrite in the primary ores. In the oxidized ores cllprite, tenorite, and trace brochantite have been found.

Jan 1, 1976

This paper deals with the Australian taxation laws, and in particular the income tax laws, as they apply to mineral exploration and development both in Australia and off-shore. The Australian tax laws are imposed principally at a Commonwealth level. The most important Commonwealth taxes are Income Tax, including Capital Gains Tax, Fringe Benefits Tax, Sales Tax, Customs Duty, Excise Duty and Bank Accounts Debits Tax. The States of Australia impose Stamp Duties and Financial Duties, Payroll Tax and Land Tax. The Australian Income Tax Law including Capital Gains Tax, is the most significant tax in the country. The principal features of the income tax law are as follows: tax is imposed on a taxable income being the assessable income less allowable deductions; a full imputation system of company tax applies; a foreign tax credit system applies to both companies and individuals; capital gains are taxed as income and subject to income tax rates but the gain is inflation adjusted. Australia has negotiated tax treaties with most of its trading partners based on the OECD model; and special tax concessions apply to the mining industry.

Jan 1, 1987

By S M. C Verryn

The amount of raw material used in the production of cement can be reduced by partially supplementing it by pozzolanic waste material without changing its properties negatively. This paper discusses results of an investigation using slag from the Pt industry, from the production of steel using Midrex processes as well as fly ashes from different coal power plants in South Africa. These are blended in a 20 per cent slag or fly ash to 80 per cent cement ratio. The properties of the mixtures depend on the phase composition, chemistry, grain size and the sources of the materials. The results are promising, but show variable behaviour depending on slag and cement composition. Compressive strength tests as well have heat flow curves showing the hydration behaviour, indicating that 20 per cent addition of slag or fly ash to ordinary Portland cement is viable. There is a large potential to use slag in cement mixtures and this study can be used to develop cements that will positively influence CO2 emissions and help to reduce large slag and fly ash stockpiles.

Jan 1, 2008

By Morley I. W

Offshore minerals legislation has been introduced to provide jurisdiction over the exploration and recovery of mineral resources, particularly petroleum, from the territorial waters and parts of the continental shelves adjacent to coastal states. Ratificat- ion of the 1958 Geneva Conventions on the Law of the Sea has provided some measure of international agreement amongst signatory powers. Because the relationship of the Australian States to the Commonwealth in their federal system, the Australian offshore petroleum legislation is of particular interest. The customary role of the States in mineral resources management, which has extended to the offshore, is under challenge from recent unilateral Commonwealth Government legislative actions in the fields of mineral resources jurisdiction. Environmental considerations provide an additional issue, as yet unresolved, with the delay in submission of the Report of the Great Barrier Reef Petroleum Drilling Royal Commissions

Jan 1, 1974

By J de Vries

Arthur Page, a past President of AT&T said:All businesses in a democratic society begin with public permission, and exist by public approval. Product stewardship in its most basic form is simply risk management applied to the products we produce. Conceptually it may be considered as a more expansive approach to many existing safety, heath and environmental programs. Key differences include the extension of responsibility beyond the direct control of management, and consideration of the implications your products and processes have on the broader community, as opposed to the confines of an individual mine site or operation. This paper reviews the processes used by Orica Ltd to manage its product stewardship program. OricaÆs product stewardship program is expansive and supports activities and business that range from manufacture and delivery of commercial explosives and sodium cyanide to mines throughout the world, supply and operation of municipal water facilities, and manufacture and distribution of consumer products such as household paints and adhesives. We highlight the development of the program through experience both good and bad, and by use of case studies to illustrate how an active product stewardship program is an effective business risk mitigation strategy.

Jan 1, 2006

By Liu H, Chen S

Natroalunite is one of colouring minerals in kaolin. In this investigation, natroalunite, on which Ca(II) was adsorbed, was flocculated by HPAM and kaolin was depressed in suspension. The adsorption of Ca(II) on the natroalunite surface was studied by zeta-potential measurement and Auger Electron Spectroscopy analysis. Ca(II) was adsorbed more on the natroalunite surface than on the kaolin surface. The mechanism of Ca(II) adsorption was considered to be chemical adsorption on natroalunite and to be physical adsorption on kaolin. It has been found that Na6P6O18 and Na2Si04 can strongly affect Ca(II) adsorption on the surface of kaolin, but weakly on the surface of natroalunite. The effects of degree of hydrolysis and the molecular weight of HPAM, the effect of pH and the effect of Ca(II) have been studied. The kaolin ore, containing SO3 1.05 per cent has been processed with this method. The products only containing S03 0.36 per cent and the weight ratio of concentrate 52.27 per cent were Obtained.

Jan 1, 1993

By P Hucker, E Hall

Harmony Gold operates the Mount Marion underground gold mine near Kalgoorlie, Western Australia. The mine consists of two ore zones, East and West, and mining of these zones is currently conducted using the sublevel caving method. When mining commenced in the Western zone, the span was insufficient to induce caving of the country rock above. Dyno Nobel, together with Harmony and 360 Drilling, developed an innovative drill and blast solution in order to promote cave propagation and improve the safety of personnel at the operation. The solution involved a series of shallow angle drill holes up to 90 m into the hanging wall of the West zone. These were charged with Titan« 7000 underground bulk emulsion and the HotShotÖ electronic initiation system. The blast used over seven tonnes of emulsion and 46 detonators and achieved the desired result without damaging nearby mine infrastructure.

Jan 1, 2007

A sequence of ultramafic units, very well exposed in Munro township in the Abitibi areal, of the Cahadian Shield, exhibit features which indicate that they are sub-aqueous extrusions. They occur within a sequence of tholeiitic pillow lavas, thin graphitic sediments. and large differentiated sills. The units range from a few metres to more than 250 m in length and less than 1 m to over 30 m in thickness. Over 60 individual units, occurring as flat pancakes on top of one another, make up a total exposed thickness of 150 m. The units have formed from a magma composed of a very olivine-rich picritic liquid carrying up,to 40 per cent olivine phenocrysts in suspension. Different units display a variety,of cross-sectional profiles. As an example of the most extreme type of profile, a typical unit 2 m thick consists of a cap of highly jointed fine-grained quenched rock, 10-30 cm thick, which becomes coarser downwards, grading into a zone composed of radiating and criss- crossing skeletal olivine crystals forming the well-known spinifex texture. This becomes even coarser-grained downwards, with "books" of parallel platey olivine crystals developing sub-perpendicular to the plane of the units. Beneath this zone, which may be up to 1 m thick, there is an abrupt transition to a cumulus-textured rock composed of rounded

Jan 1, 1973

This subject of paramount importance in many modern plants employed in the extraction of gold from ores by cyanidation, involves several considerations.With the old-type "slimes decantation" process, using several tanks of large dimension, installed at high capital cost, it was frequently possible to obtain good settlement over a protracted period, but the disability of indifferent response to subsequent filtration and washing of the residual pulp, after decantation of the supernatant pregnant solution, was often present.In modern cyanidation practice, the tendency is to reduce capital expenditure by continuous processing of the ore pulp in a plant of less volume, but capable of handling more tonnage through-put and yielding, coincidently, less residual dissolved gold in the final pulp residues.INHIBITORY FACTORS.These involve a study of the effect of the circuit water or solution employed in milling and treatment, the amount of "primary" slime occurring in the ore broken underground, the constitution of the "walls" underground, the inherent occurrence of colloidal slime in partially decomposed ore, and the presence of kaolinised and ferruginous clayey structures carrying payable infiltrations of gold values, to mention some of the troubles encountered in practice. Practically all the difficulties occurring are due to the presence of colloids (using the metallurgical as apart from the chemical definition of the term), either...

Jan 1, 1935

By J Sarvinis

The design and operational aspects of fluidised solids transfer-cooling devices will be discussed in this presentation. The devices include air slides and fluoseals (also called seal pots, loop seals, etc), which are widely used in metallurgical plants and other processing plants. Cooling can be achieved while solids are transported in the solids transfer devices. The units combining solids transfer and cooling provide compact and clean plant layouts and also reduce capital and operational costs. Fluidised devices provide excellent gas-to-solids and gas/solids-to-surface heat transfer rates, hence high cooling efficiency. Fluidising gas, such as air, nitrogen or other gases, can be used as direct cooling mediums. Coolants such as water, steam and other liquid or gas cooling fluids can be used as indirect cooling mediums via tube coils immersed in the fluidised solids. The fluidised transport devices share some common features with fluidised bed equipment. The air slide is similar to a linear fluidised bed while the fluoseal is similar to a circular fluidised bed. Therefore fluidised bed design techniques are applicable to the design of the air slides and fluoseals. The heat and mass balance and temperature profiles of the devices concerned will be discussed in the presentation. The design criteria and operational philosophies of the critical components such as tuyeres and air spargers will also be discussed.

Jan 1, 2006

THE auriferous sulphide ores of the eastern end of Gippsland, and notably of the Cassilis and lVIitta districts, are amongst the most complex and refractory in Victoria-perhaps in Australia. The minerals occurring in these ores are pyrite, arseno-pyrite, zincblende, galena, and (in smaller amounts) some of the copper, sulphides, as chalcopyrite and covellite; and some of the antimonial minerals, notably stibnite and jamiesonite. In the oxidized portions of the lodes, the oxidized lead and iron minerals, and small amounts of the hydrated arseriiate of iron, are found.In the Cassilis mine, near Omeo, copper is present usually in quantities of under 1 %. The magnetic sulphide of iron is of fairly common occurrence. In, the upper levels of the Cassilis mine tin was usually present, the amount going up to 3% in some samples of concentrates. These minerals occur sometimes banded, but usually as an intimate mixture-pyrite and arseno-pyrite predominating. The gangue is usually quartz (blackened by enclosed particles of sulphides). Calcite, magnesium silicate and felspar are also present in varying amounts.

Jan 1, 1911

By A A. Struthers, A D. Farmer

Power ultrasound may be applied to enhancing the processing of minerals. The enhanced performance is achieved through the very localised high-energy release at the mineral surface from the collapse of cavitation bubbles produced by power ultrasound. This gives rise to two effects: initially, the rapid cleaning of mineral surfaces û of oxidation products and coatings of fine adhering gangue minerals û and the attenuation of the boundary layer at the mineral surface during leaching, which allows fresh leachant to contact the surface more readily. Work carried out at CSIRO in conjunction with Tiwest Joint Venture has demonstrated that it is feasible to apply ultrasound to the leaching process in order to enhance the removal of contaminating minerals. When applied to the production of synthetic rutile from reduced ilmenite produced by the Becher process, the use of ultrasound proved beneficial to both the aeration and the final acid leach process. The effect of ultrasound was less marked in the case of the aeration process, once the method of introducing and dispersing the air was optimised. In the subsequent acid leaching step of the Becher process it was found that the application of power ultrasound could reduce leaching time to about one quarter of the time required when only agitation was employed. Projected capital and operating costs, based on currently available commercial equipment, are also presented, and indicate that the use of ultrasound is commercially as well as technically feasible.

Jan 1, 2001

In the last few years a number of mineral laboratories were established in Indonesia coinciding with the increase in gold exploration in the region. Prior to this, much of the analytical work was sent outside the country,however this is no longer neccessary.

Jan 1, 1990

Cut and fillstoping using hydraulically placed mill tailings has become an essential feature of stoping operations in Kalgoorlie. ' Approximately 30 per cent of the total production is currently mined by this method. Fill is prepared by thickening or cycloning and is gravitated or pumped underground. The average pulp density is 70 per cent solids by weight, Recent cost reducing innovations are the use of steel passes, corrugated iron manways, polythene film sealing, and the replacing of vertical cement lined pipes with boreholes. TTTTTI rvr T Trim r l1TT

Jan 1, 1964

Geomorphology is one of the most basic elements in geographic enviroments. Geomorphological mapping is significant in the spatial distribution of representing land form and understanding various features of geomorphology. Geomorphological mapping began very early in China, as the map, showing conekarst(karst pinnacles) of Juiyishan, Hunan province, it was drawn in 168B.C., which was excavated from Han tomb. Mawangdui, Changsha. Its original idea of map-making is rather similar to that of modern map and could undoutedly be the oldest map of tropical karst discovered in the world.Before liberation, landform mapping was done piecemeally and only a small number of maps were prepared by a few editor as insets.

Jan 1, 1990

Authorisation No.66 (to Prospect) was allocated to R.W. Miller & Co. Pty. Ltd. on 1st November, 1976. Exploration has brought coal reserves to measured status in the Jerry's Plains sub-group which are about 550m. thick. The immediately lower Vane Sub-group, about 200m. thick, includes about 20 seams. The total measured and indicated reserves of the two sub-groups based on the criteria adopted by the company amount to 1362 million tonnes in situ. This very large resource is subject to very many mining constraints both physical and economic which limit the saleable reserves under present conditions to about 120 million tonnes. The results of the calculation of reserves after exploration is complete in a deep multiple seam situation is dependent upon the criteria used to include or exclude seams in the reserves. These criteria are state- ments of the miner's expectations of the market, mining and coal preparation technology, local and national politics and the law as it may be applied in the future.

Jan 1, 1979

By A I. M Ritchie, G P. Timms

Monitoring of water infiltration into WhiteÆs waste rock dump at the Rum Jungle mine site in the Northern Territory, Australia, started in 1983, and has since produced a unique and long-running data set. Following closure of the uranium mining operations at the site, a soil cover was constructed on the dump in 1984 primarily to reduce water infiltration into, and the quantity of low quality effluent out of, the waste material. The performance of the cover in reducing water infiltration has been monitored using ten lysimeters installed across the dump prior to construction of the cover. Over the past eight years or so, the average infiltration rate as measured by the ten lysimeters appears to have risen compared to the early years of monitoring. The significance of this apparent increase is discussed given the variability observed in the data from individual lysimeters, and the variability in the rainfall. Estimates of the infiltration rate as measured by each of the lysimeters are examined using statistical tools. It is concluded that the infiltration rate has increased with time and with increasing rainfall. The increase with time is a stronger factor than the increase with rainfall. It is further surmised that the cover system at the locations of the lysimeters is less effective now at reducing infiltration into the dump than it was when newly installed.

Jan 1, 2003

A review of publicly available coronial inquiries into fatalities that have occurred within the resources sector since the year 2000 reveals that a loss of corporate memory has been a contributing factor in 40 per cent of these accidents (National Coroners Information Service, 2010, Appendix B). With the highest levels of employee turnover within the Australian economy, increasingly complex operations and an ageing workforce, the management of corporate memory within the Australian resources industry poses a significant and often unrecognised safety risk.    The North Parks airblast of 1999 is used as a case study to highlight how corporate memory loss poses a significant hazard to resources projects and how such incidents will continue to occur if corporate memory is not effectively managed. Best practice from other industries is discussed to demonstrate how knowledge management systems can effectively work. This paper discusses how systems can be put in place within the geographically diverse resources sector, and how at the heart of any knowledge management system a culture of knowledge management needs to exist within an organisation.   The paper then discusses the importance of retaining key personnel and utilises findings from primary survey data collated in 2009 to show the size of the retention problem within the industry. From the data possible solutions to retaining key staff are proposed.   Finally the large and increasing role of contractors and consultants within the industry is discussed and methods of managing their knowledge are proposed.

Jun 1, 2010

By Nash B. G W

In June 1976 a 600'tonne/day manganese ore sinter machine, with on-strand cooling, was commissioned at the plant of Tasmanian Electro Metallurgical Company Pty. Ltd. at Bell Bay, Tasmania. This machine was installed in order to utilize manganese lump ore screenings generated in the preparation of raw materials prior to charging to the electric smelting furnaces at Bell Bay. Since commissioning, trial sintering of a number of different grades of manganese ore fines from Groote Eylandt Mining Company Pty. Ltd, has been conducted and suitable sinter has been produced from these different grades. The sinter produced is used as part of the furnace burden in both ferro manganese production and silico manganese production. The inclusion of sinter as part of the charge in the production of ferro manganese has considerably improved furnace operating conditions and performance.

Jan 1, 1977

By Eldridge B. J

During recent years, Central Queensland has experienced a boom in its coal mining industry. This has involved many companies in projects requiring large capital expenditure. As with most projects of this size, many operating problems are now being experienced which were unforseen at the feasibility stage. One of these problems is the failure of pit slopes and spoil piles at some of the strip mining operations. There have been serious stability problems associated with Utah Development Company's strip mining operations in Central Queensland, in particular the Goonyella Mine. A field investigation programme was under- taken to determine the cause of highwall and spoilpile slope failures. Spoilpile failures were found to result from weakness near the spoil/floor contact zone. Highwall failures were found to result from a combination of unfavourable bedding plane dips and weakness, and the presence of joints in weak o~erburdep; Satisfactory solutions fa the staiity, problems are difficult to formulate, and-field stability experimentation is still at an early Stage.

Jan 1, 1974