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By Ken Campbell

Exploration and mining in Third World countries will essentially be an exercise in the transfer of technology. We must not underestimate the effort it will take to develop the necessary industry peer group in these nations which can accept the latest western technology and use it to good effect.

Jan 1, 1994

World class ore deposits can be defined commercially as deposits which contain metal concentrations in the upper quartile of resources size and/or grade, world wide, from which economic extraction can be undertaken, over a production period exceeding ten years, at a cost below the weighted average cost of cumulative production of the contained principal commodity of mines world wide.

Jan 1, 1993

By D H. Bell

The potential for extracting gravel materials from active floodplain and channel areas has been investigated for three West Coast rivers û the Grey, Inangahua and Whataroa. Studies have focused primarily on resource availability and replenishment, but there are clearly also environmental management issues associated with such a proposal. The potential uses for of extracted materials include roading and concrete aggregates, as well as railway ballast, whilst a major benefit would be in assisting with flood control and channel maintenance in a naturally aggrading system. Sediment movement in the rivers has been examined at three scales; long-term (>100 years), medium-term (10 - 100 years) and short-term (<10 years). Long-term sediment movement is based on geological and geomorphological information, such as cyclic fan development and down-cutting in the Whataroa River where sediment input appears to be largely controlled by Alpine Fault rupture events. Medium-term assessment relied on air-photo interpretations over a period of about 50 years, with the mapping of channel changes and bank migration. Short term changes were evaluated from gauging records and other hydrological data, and took account of the development of an armour layer in these gravel-bed river systems. It was concluded that sediment in the lower reaches of each river was suitable for most aggregate uses, although input of more weathered Greenland Group materials in the upper reaches (eg of the Mawhera-iti or Little Grey) resulted in product that was not satisfactory for sealing chip or railway ballast. Of greater importance was the fact that short-term studies showed that a minimum threshold of flow was required for gravel entrainment, and that significant sediment movement only occurred above the one-year return period flood. Ongoing monitoring of river profiles, with accompanying flow gauging, would clearly be necessary were a substantial increase in river bed extraction to be permitted by The West Coast Regional Council.

Jan 1, 2003

By P Cameron

Many products and technologies have been developed from outcomes of research projects carried out by the Julius Kruttschnitt Mineral Research Centre (JKMRC). When these products and technologies are applied to the design and optimisation of blasting, comminution and separation, improvements in profitability can be realised. In 1970 Alban Lynch promoted two practical ideas to improve plant operations: Ore and equipment properties can be separated allowing experience with one type of ore or equipment to be transferred to other types of ore and equipment. If this experience was encapsulated in a mathematical model, then these properties could be combined and used to simulate (ie to design and to optimise) complete mineral processing circuits. Many problems associated with scale-up from laboratory to industrial equipment could be eliminated by experimental work on full-scale equipment in the plant. Many JKMRC research projects have focussed on the development of models of unit operations in mineral processing and their application to process simulation. Models of comminution and classification developed at the JKMRC have been used since the early-1980s. Ore characterisation techniques developed to support these models are licensed world wide through JKTech. The application of comminution modelling techniques to blasting, which optimises the process feed size distribution is used in Mine-to-Mill? projects. The advances in the understanding and modelling of froth flotation over recent years have provided the opportunity for integrated ore characterisation and process optimisation from resource to product. JKMRC project outcomes often provide proven opportunities for the mineral industry to improve performance and productivity. JKTech was established in 1986 to commercialise and market the most promising outcomes and thus ensure their continuing availability to the mineral industry. These include: commercial software (JKSimMet, JKSimBlast and JKMetAccount); monographs (Comminution and Blasting); technologies (Mine-to-Mill? and flotation optimisation); and hardware products (JKFrothCam, JKJetLift? and the Mineral Liberation Analyser). This paper summarises these technologies and their benefits.

Jan 1, 2002

The 1980's has seen a revolution in gold mine developments in Australasia. We are witnessing a near ten fold increase in all phases of gold mine development ranging from exploration through to production. Ounces produced have yet to mirror this activity but have increased from a low point of 600,000 in 1980 to 1,800,000 ounces in 1985 in Australia alone. In 1980 the region had less than 10 gold mines, yet 14 new mines started production in 1985 and as many as 28 might start up in the next 18 months. Developing gold mines in the 1980's in Australasia has not been the easiest of jobs, yet the great number of new developments suggest that we have entered a new era that will rank in history along with the 1850's, 1890's and 1930's as high points.Within- our Australasian region two very distinctive styles of gold deposits are being discovered and developed. On the Australian mainland the new mines are in geologically old rocks and are mostly the low grade haloes surrounding worked out high grade deposits. Most are limited life open pit operations depending on recent innovative carbon-in-pulp or heap leach technology. In the Pacific Islands region the style of discoveries are geologically recent, large bulk-low-grade deposits often geologically analogous to porphyry copper deposits. These deposits are typically 10 to 20 times larger than those being proved up on the Australian mainland.

Jan 1, 1986

The JORC Code, which has been in existence as a Code incorporated in the listing rules of the Australian Stock Exchange and New Zealand Stock Exchange since 1989 and 1992 respectively, has been revised and will be re-released in 2003. This revision followed a call for submissions in December 2001, the publication of an exposure draft in late-2002 and an exposure period during which a large number of constructive comments were received. These comments were reviewed and a further exposure draft released as part of the current exposure draft of the ASX listing rules. It is anticipated that the final Code will be incorporated into the stock exchanges listing rules in late-2003. The 1999 JORC Code has been the standard on which other reporting Codes have been based, each of which has contained refinements. Three in particular, the Reporting Code from the United Kingdom/Ireland/Western Europe, the new Canadian Reporting standards and the SAMREC Code from South Africa, influenced JORC in the preparation of the 2003 JORC Code. Whilst there are differences between the 1999 Code and the 2003 Code, these changes are mainly in the guidelines. The Code definitions, which are largely in accord with agreed international definitions, remain substantially unchanged. The two main changes in the 2003 Code are the requirement for a Competent Person to be responsible for the documentation relating to the reporting of Exploration Results, and the introduction of æRecognised Overseas Professional OrganisationsÆ as overseas organisations to which Competent Persons may belong. Other changes include: clarification of the reporting of exploration targets or potential; the rearrangement of the diamond reporting clauses; the introduction of guidelines for the reporting of Industrial Minerals; modification of the coal clauses and recognition of the new Coal Guidelines; and the introduction of a guideline encouraging the discussion of relative accuracy and confidence in resource/reserve estimates. Other lesser changes to the Code are listed and discussed briefly. The release of the 2003 JORC Code maintains the standard set by JORC as a world leader in the development of mineral reporting Codes and their adoption by industry.

Jan 1, 2003

By I D. Hair

A numerical groundwater model was used to predict the nature of interactions between heavy mineral sands mining operations and the groundwater regime at North Stradbroke Island, Southeast Queensland. North Stradbroke Island is formed mainly of massive vegetated Cainozoic aged dune sands. Since the 1950s, a number of operations have mined rutile, zircon and ilmenite on North Stradbroke Island. In such mining operations, a dredge and an associated processing plant are floated in a pond either above or below the prime groundwater table The numerical model was based on the North Stradbroke Island Groundwater Management Model, developed in 2001 by the Department of Natural Resources and Mines (NR&M). This model was constructed using the modular, cell-centred, finite-difference groundwater flow model, MODFLOW, developed by the United States Geological Survey (USGS). The NR&M model was refined to improve model resolution and detail for simulating dredge mine paths. Of particular interest were: water table fluctuations induced by mining for the identification of slope stability risk; the optimisation of sand spear arrays supplying mine make-up water requirements; inflow and outflow rates to the dredge pond for overall mine water balance; and interactions with Eighteen Mile Swamp and water supply bores controlled by the Redland Shire Council (RSC). Depending on the water level in the dredge pond compared with the surrounding groundwater table, water either flows out of the dredge pond into the groundwater regime or from the groundwater system into the dredge pond. The MODFLOW river package (RIV) was utilised for the modelling study. Dredge pond movement was simulated using specialised software developed by Watermark Numerical Computing (WNC) to interpolate pond positions and map the dredge path to the model grid both spatially and temporally. As tailings placement affects the groundwater system through increased recharge, the MODFLOW recharge package (RCH) was utilised to simulate different recharge efficiencies. Long-term model predictions were made for the period from July 2002 to May 2021. Results of the modelling showed that exchanges of flow between mining operations and the groundwater regime could be effectively managed. The study provided valuable information which was used to develop an appropriate mine water management plan.

Jan 1, 2003

Jan 1, 2004

By Koivunen P

Both development and production drilling are amenable to productivity improvement through partial or full automation of drill jumbos and rigs. Various developments in this regard are described.

Jan 1, 1986

There are many types of environmental audit: compliance, impact, risk and management audits; internal and external audits; single and multiple-project audits. All are becoming increasingly important in corporate management as new legislation confers increasing personal liability on directors, executives and staff of corporations and agencies in both private and public sectors.

Jan 1, 1990

The paper examines the current status of risk and accepted practice in mining geomechanics. It explores some deficiencies in human capital, risk analysis and our future technical needs, and suggests ways of improving our estimates of slope reliability through knowledge sharing and research.

Jan 1, 2003

An Investigation of Cobalt Recovery on a Complex Oxidation Mine with High Per Cent of Mud

Sep 13, 2010

By Leaning R. W, Goodman P. J, Lidgate P. N

The impact of computer based design tools on the engineering industry has been enormous. With the advent of computer aided design and its continual evolution into tools such as 3D design and photogrammetry the face of the engineering office ha

Jan 1, 1998

The direction taken by mineral processing in the next 20 years will be determined by sharing of Australia's resources to fill world needs; by the low energy costs in Australia; by environmental considerations; and by Re- search and Development contributions. Examples of the interplay of these factors are given by consideration of eight minerals.

Jan 1, 1981

The paper will review the fundamental policy issues and options that have been considered in the determination of the proposed allocation and pricing (ie royalty) regime for minerals under the Crown Minerals Act 1991. It will consider such influences on the new disposal, allocation, pricing and management arrangements for the Crown's mineral estate as the existence of prior ownership claims, exclusivity in access, the requirement for cost recovery and the treatment of contingent liabilities.

Jan 1, 1993

By Denholm WT

The Dittmer process for the debismuthising of lead by electrolysis beneath molten caustic soda has been scaled up to 100 kg lots for batchwise operation and to 20 kg per hour for a continuous flow of lead. Bismuth was decreas- ed from 0.03 to less than 0.005 wt. per cent for an electricity consumption of 220 kWh per ton of lead. Lower bismuth levels may be readily achieved if required.

Jan 1, 1975

The paper looks at those factors which led the Latrobe Valley Community Forum to .focus on shortcomings of the consultative process. that existed around the 1980 period, and the limitations on the ability of the community of the Latrobe Valley to have input to the factors affecting their quality of life. Through a review of the Yallourn East Field Extension project it seeks to demonstrate the changes that have occurred and some of the shortcomings still existant in the consultation process.

Jan 1, 1992

As defined by both the Australian and New South Wales Governments the Illawarra consists of the Tablelands, the Local Government areas of WingecarribPe Shire, Bowral Municipality and Mittagong Shire, the Wollongong sub-region consisting of Wollongong City Council, Shellharbour Municipality and Kiama Municipality and finally the Shoalhaven Shire. I intend here to concentrate on community development in the Wollongong sub-region.

Jan 1, 1976

By Mills J. C

Concentration ranges are presented for 15 trace elements not previously reported in Australian bituminous coals. The results were obtained by instrumental neutron activation analysis, which has sufficiently high sensitivity to enable determination of many elements directly in coal at concentrations less than a few µg/g. The ranges found in Australian coal are similar to the ranges reported in North American bituminous coals.

Jan 1, 1983

By G Wood, B Lumsden

A statistical ærandomised block designÆ full plant trial of magnetic conditioning of flotation feed was undertaken at Rio TintoÆs Northparkes Mine in New South Wales. Magnetic conditioning of flotation feed has been shown to improve the flotation of 20 38 ¦m fraction for either metal. Approximately half the copper and gold losses at Northparkes are in the

Jan 1, 2007