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By Niemann G

The paper addresses certain mining provisions of the Aboriginal Land Rights (Northern Territory) Act 1976 and the development of Mining agreements negotiated pursuant to Section 43 of the Act. Difficulties for miners and Land Councils alike arising out of the operation of the Land Rights Act will be discussed. Possible scenarios for the resolution of these difficulties will be proposed.

Jan 1, 1984

The optimization of management structure systems for coal mines is undertaken with the use of economic and mathematical models of the monitoring, manufacturing, and functional subdivisions of the systems. The main para- meter to be minimized is economic loss result ing from organization faults and this is achieved, in part, by optimum distribution of both technological objects and engineering and technical personnel. Models used are of the "gated" type, parameters for which are derived from analysis of manufacturing processes and from automatic information systems. The use of these models ofmanagement structures is only part of the process of optimization of those structures for coal mining operations.

Jan 1, 1977

The success of any industry depends on the planned integration of the policies and resources of the key components of the Australian economic and political structure - government, industry management, education, research, and the human resources of the industry. The Australian Mineral Industry, like Australia itself, has grown and developed at a rate not foreseen by many of our founding fathers and early industry leaders. Hence, now, as we approach the 21st Century, we need to re-think our approach to the significant new problems that are beginning to face both government and the Mineral Industry. Government initiatives, government information and support services, industry re-structuring, and research and development support, need to be carefully re-evaluated, re-diredted,. and strengthened, so that government, the community, and the Mineral Industry produce and receive the optimum education and research strategies and services. The support of academics and researchers, the development of facilities, and the design of new Courses for the future successful and beneficial exploitation of minerals need particular consideration.

Jan 1, 1986

By W A. van der Westhuizen

Selective mining played a major role in saving a mine and a communityÆs existence as well as creating a working culture that is the model for all KumbaÆs mines. The successes that resulted from selective mining led to receiving KumbaÆs highest award (it was the Gold Medal Breakthrough project of 2003) as well as the productivity award at the National Productivity Institute award ceremony in 2004. Kumba was established in November 2001 (previously Iscor Mining). The new company identified Mineral Resource Management (MRM) as one of its key drivers and an initiative was launched to define MRM in the Kumba way. Best MRM practices at the Kumba mines were included in the definition. Selective mining was born out of this initiative. One of the key principles of good MRM practice was identified as: æThere must be a balance in the operational processÆ. This principle was applied with great success at Thabazimbi Iron Ore mine in the Limpopo province, South Africa. The emphasis of this paper will be to show how value can be unlocked throughout the whole mining value chain. In the past (up to 2001) the mine went through a number of crisis situations: planned production performances were not reached, the stripping ratio was extremely high with two new pits, the product beds were not of constant quality, slope failures were big risks, flooding could and did cut off half of the ore supply, and restructuring demoralised staff.This paper focuses on: selective mining throughput drivers, and selective mining and its role in achieving this balance.The results were dramatic, with huge improvements in production results, stockpiles, plant yields and product bed specifications. The mine was brought into balance and a self feeding loop was created with positive spin-offs up to this day.

Jan 1, 2005

Portfolio management tends to separate the functions of Asset Allocation and Stock Selection, so the person responsible for reviewing an expert's report on a company would typically be choosing between companies rather than between a company and cash or bonds. How these choices are made depends on the investment time horizon, philosophy and style. Two styles, momentum investing and value investing are contrasted and the role of valuation methods within the framework of each style is evaluated. Finally, pricing is distinguished from valuation.

Jan 1, 1994

By Foudoulis C, Smith CB, Drew RM, Sun S-S, Sheraton JW, Hall AE

Primay (syngenetic and protogenetic) inclusions - i.e. minerals formed during or before diamond growth and encapsulated in the diamond - provide important information on the origin of diamond. Recent Rb-Sr and Sm-Nd dating of such inclusions has yielded crystallization ages older than their volcanic host, implying that diamonds are mantle xenocrysts. In this paper we report results of studies on the nature of syngenetic inclusions and the carbon isotopic compositons of the host diamond from the West Australian diamond deposits at Argyle and Elllendale. The Argyle diamonds are dominantly, of eclogitic paragensis and are characterized by strongly C depleted compositions. We have recognized an association of stone morphology, inclusion type and carbon isotopic composition amongst the Argyle stones, and on the

Jan 1, 1989

By Murdaugh W

The application of photogeological techniques and analysis of more advanced remote sensor images can be a cost and time effective tool in the search for desert placer gold deposits. Examples are given of regional analysis using standard false color composit Landsat images and conventional black and white aerial photography. The examples include identification of sites to sample to evaluate the pathways of .alluvial gold migration and identification of potential sites of concentration. The results of these studies developed an increased number of target areas and exploration in proceeding with promising results. In addition to the development of additional target concepts and identification of specific target areas data useful to evaluation of mineability can also be obtained from photogeological investigation. Some indication at least can be obtained of the existence of duricrusts and salines that may hamper mining. Identification of possible sources of water is another important task in the desert environment. In addition indications of the clay content of the material to be worked is very important because of its economic impact on operational costs and overall recovery. The application of photogeology to these questions is discussed.

Jan 1, 1988

By J C. de Vries

When times are tough in the mineral industry û as they have been for some time û typical responses by mining companies are to cut costs and/ or increase production. The latter is seen to spread fixed costs, thereby also reducing unit costs per tonne mined. However, most mineral deposits respond to increased production rates by lowering ore grades, so the reduction in cost per tonne of ore does not necessarily result in a reduced cost per unit of metal produced. The authorsÆ experience is that this process often leads to a mine plan that is a long way from optimal. Producing to the point where marginal cost equals marginal revenue may work well in a manufacturing operation, but it is not necessarily the best strategy for a mining company with a depleting resource. Variations in tonnage and grade with depth, ore reserve optimism and a variety of other factors conspire to produce variations in production rates and grade that often result in suboptimal outcomes and potential mine failure. Added to this is the focus of industry analysts and senior corporate management on such measures as unit costs and ounces in reserves. This is perceived to have the perverse effect of driving the share price down when strategies are adopted that actually improve the value of the mining operation, and vice versa! Many mine failures can be prevented by a close examination of the tonnage grade curve and an understanding of how margins, net cash flows and resulting business risk change with cut-off grades and rates of production. A few relatively simple analyses early in the evaluation of a project can demonstrate the tradeoffs between the main decision parameters, leading to right-sizing of the operation. Once major commitments to major capital items have been made, and reserves have been publicly reported, optimisation of the operation becomes much more difficult than if it had been done earlier. Such investigations can also identify the upside potential and downside risks associated with factors outside the companyÆs control. Many strategies that may enhance value in the good times significantly increase the downside risk in the bad times. What is often called risk analysis typically looks at superficial issues, and does not evaluate the major factors leading to the potential for financial disaster. This paper illustrates some of these major risks, and demonstrates how they may be fully evaluated so that corporate decision makers can make fully informed decisions that take account of the real risks.

Jan 1, 2003

Tasker (1985) has detailed the accepted practices for constructing polygonal blocks of influerrce in the estimation of ore reserves. Further he suggests that users might fall into traps such as omission or overlap when determining the area of influence for each sample point.As an example of these types of errors Tasker (1985) describes under "Coverage ofthe Area" how 25 per cent of the exploration area will not be included in an equiangular triangular grid where hexagonal blocks of influence are used.The introductory suggestion of Tasker (1985) of "incorrect procedure" by Rudenno (1983) (and Armstrong (1983)) reiterated around the Figure 2a of Tasker (1985), is based on the brief description of the polygonal area of influence by Rudenno (1983). That description is not too different from that given by King, McMahon and Bujtor (1982).

Jan 1, 1985

I WISH to express to the members of the Institute my sincere appreciation of the distinction which they have conferred upon me by again making me their president. It also gives me great pleasure to once more welcome the Institute to Mount Lyell.Since your last visit certain improvements in plant have been made, which I trust you will have found interesting, and which show that, though located in a remote corner of the world, we are abreast of the times.The opportunities which a recent lengthy trip to America has given me to observe the degree of interest which our local smelting practice continues to arouse in metallurgical circles make it seem appropriate that I should take advantage of your visit to lay before you some detailed information on the more practical features of pyrite smelting, particularly as carried out at Mount Lyell. There are only a few places in the world where the method is now being practised in approximate purity-only about half...

Jan 1, 1915

Universities have had a long history in the education of geology graduates, Analysis of this history reveals a record of success, as judged on a world basis. However there have been significant changes in the last 20 years that have impacted on the ability of universities to continue to provide their traditional style of geology education. These changes have increased in the last 10 years. In the teaching side, there has been a change in expectations. Additionally the increasing workload decreases the value of each academic to perform the tasks needed by the new education. In the area of research, the funds provided have continued to decline, in both real and absolute terms, and it is now necessary for universities to seek out funds to pay for their postgraduate research. Additionally, the universities have slipped into the error of what cahn only be termed "academic incest", and research student mobility has decreased to an undesirable level, stifling initiative and new ideas in a number of cases, The only solution is for Government monies to be "directed" - ie that the postgraduate student must leave his or her original university in order to receifve the research stipend/scholarship. On the government front, the government and its agencies have not adequately analysed and recognised the need for the redirection of education and research funds into the needy areas of science and technology, especially those that related to the minerals area.

Jan 1, 1986

By Mahoney BK

The development of simulation models to reflect accurately the operations of a port and its associated transportation systems can be an expensive and time consuming process. However the complexity of such operations leaves little choice for other than simulation techniques since analytical methods are rarely appropriate. The development of suitable software has now reached the stage that these techniques can be used with confidence. Types of simulation models and their requirements are discussed together with the results from some recent applications to the planning and management of bulk terminals.

Jan 1, 1983

Brand se Baai, on the North-Western Cape Coastline of Southern Africa, is the site of the Namakwa Sands Limited Heavy Mineral Sands Mining Operation. The mine is a 14 000 000 tonnes per annum open-cast strip-style mining operation using truck and excavators to mine the sand. The orebody consists of relatively unconsolidated sands reworked by fluvial, marine and aeolian mechanisms. The total orebody includes three primary ore types, namely the Red Aeolian Sands, the Dorbank (a hardcap layer) and the Orange Feldspathic Sands, which forms the bulk of the resource. Mine planning and scheduling is done using a 50 m + 50 m variable bench height system with three primary bench heights. The Aeolian and Dorbank each have a bench that varies with their thickness of up to a maximum eight metres and the Orange feldspathic sand, a standard bench height of eight metres. For a number of years Namakwa Sands used a complex 2D, Datamine Based, macro system to perform the resource evaluation and mine design. As the mining operations expanded it became clear that a complete system redesign was required to cope with the increasing operational pressures coming to bear on the old system. The biggest challenges facing any replacement system are the sheer scale of the mining operation (16 km long and 7 km wide resulting in a minimum of 30 000 individual 50 m + 50 m mining blocks), the size of the geological data files (up to one gigabyte) and representing the benching system accurately (as the benches follow the topography and are not horizontal). In addition to these large-scale issues, the ability to run multiple mine design scenarios was required, an aspect which the old system was unable to perform adequately. Based upon these primary difficulties, a new business process was developed which required a complete rethink of the mine design methodology as well as the creation of a new system to deplete the resource model, produce monthly reconciliation evaluations and create a ultimate pit limit based on the operations mining cost model. Using a system based on the Earthworks Mine2-4D Mine Design and Scheduling System (with its mine design and scheduling specific tools), as well as a small, customised program, massive time-savings have been made. It is now possible to run several life of mine scenarios in the same timeframe that a single life of mine run took under the old system. This paper will present the methodology and business decisions behind the new Namakwa Sands system, and detail the restructuring and development used to deal with the large data set sizes and long processing times inherent in the old system. Future enhancements to the system that will make it more generically applicable to open-cast mining scenarios will also be dealt with.

Jan 1, 2003

By Blackham M

West Wallsend No. 2 Colliery is a new mine that is presently being developed in the New- castle Coalfield by J. & A. Brown & Abermain Seaham Collieries Ltd., a subsidiary of Coal & Allied Industries Ltd. It is situated near Barnsley and is some 15 miles by rail from the port of Newcastle. The mine will produce coal from both Bore- hole and Young Wallsend seams. The Borehole seam has a working seam thickness varying from 7 ft to 5 ft while the Young Wallsend seam presents a choice of two distinct working thick- nesses, i.e. 5 ft. or 8 ft, the upper 3 ft containing much high ash material. The inter- seam interval varies from 10 ft on the western edge of the area to more than 70 ft in the central portion. The Borehole seam lies at a depth varying from 550 ft to 750 ft and the overlying surface terrain is gently undulating bushland with limited surface development.

Jan 1, 1972

The AusIMM came into being to foster the spread of professional knowledge within its client industry. It has evolved along with the Australian mining industry for more than a century. If the AusIMM is to become the world's premier mining professional body (whether by design, or by default), then draw up a strategic plan to get there. Define your strengths and market them Define the priority areas for professional competence which we most need, Target the groups within Australia who can produce the people, Create an industry peer group to speed technology transfer.

Jan 1, 1994

By Neill A, O&apos

The City of Kalgoorlie/Boulder is situated approximately 600 kilometres to the east of Perth (Fig. 1), and is the major regional centre of the Eastern Goldfields, supporting a population of approximately 25,000. The formation of Kalgoorlie Consolidated Gold Mines in 1989 brought the existing operat- ing entities adjacent to the city under common ownership and management. The Joint Venturers forming the management company are Homestake Gold of Australia and Gold Mines of Kalgoorlie (a Normandy/Poseidon com- pany). This traditional underground mining centre has been worked since 1893, yielding 40.8 million ounces of gold from ore with an average head grade of 10 grams per tonne. Historically the heart of the operation has been the famous Golden Mile located on the Eastern perimeter of the city, in the area known as Fimiston. The other significant operations that form KCGM are the Mt Percy Open Pit and the Mt Charlotte Underground Operation. KCGM's current production is 520,000 ounces per year, with the com- bined Fimiston operations (open cut and underground) contributing 400,000 ounces. The current expansion will increase production levels by a further 150,000 ounces. Traditionally 98 per cent of gold has been sourced from underground areas, however the recent upsurge of open cut operations is rapidly overturning this historical relationship.

Jan 1, 1991

The ongoing need for improved fuel economy, longer engine life, reduced emissions and greater power output has driven the need for lower charge air temperatures. Cuamins will introduce a split loop, single water pump approach to low temperature aftercooling (LTA) in 1987 with the introduction of its 1492 kW (2000 BP) 16 cylinder K Series engine. The LTA system selection process considered performance, durability, fuel economy, and total engine installed cost. The split loop system selected takes full advantage of the engine cooling characteristics to provide optimum charge air temperatures at all speeds, loads and ambient temperatures. Computer simulations and engine tests were used to determine performance for each charge air cooling alternative. The split loop system chosen offers many advantages compared to the other alternative systems studied which included air-to-air and dual loop (two radiator, two water pump) systems.

Jan 1, 1986

Acupan is considered to be an intrusive centre as several igneous phases have been emplaced in the vicinity of the mine over the past 8 Ma. They include the Lucbuban gabbro, Virac granodiorite, Ampucao dacite porphyry (ADP), Hartwell plug, Itogon plug and the multi-phase Balatoc diatreme. These intrusives have high-K calc-alkaline affinities and are grouped together as the Virac Complex.Porphyry-style mineralisation formed during the final crystallization of the ADP in the late Pliocene, with the deposition of two vein stages from high-temperature hypersaline magmatic-hydrothermal fluids. K-silicate alteration halos surround the first stage of veinlets (stage I); they are surrounded in turn by a propylitic assemblage. White sericite and/or intense propylitic halos envelop the second stage of veinlets (stage II) and grade into a weak nrnnvlitir accPmht o

Jan 1, 1990

By Robinson J

A stibnite flotation concentrate from Costerfield in Victoria was found to contain 63.3 g/t An while its sizing distribution indicated that 81.6 per cent of the material was less than 38 ¦m. A 24 hour cyanidation test by a standard bottle roll method recovered 15 per cent of this gold. Pressure cyanidation under conditions of ambient temperature, 40 per cent pulp density, an oxygen pressure of 1000 - 2000 kPa and an initial NaCN concentration of 15 kg/t, resulted in a recovery of 65 pe cent of the gold after only two hours of leaching. Aqueous pressure preoxidation of the concentrate followed by the standard bottle roll cyanidation realised gold recoveries as high as 96 per cent. Conditions of 220¦C, an oxygen pressure of 1000 - 2000 kPa, 16.7

Jan 1, 1991

By M Hino, Y Sasaki

Sustainable handling of municipal waste and sewage sludge has an important goal to recycle resources without supply of harmful substances to humans or the environment. The gasification mechanism of phosphorus from municipal waste and sewage sludge during the incineration process has been investigated to develop a phosphorus recovery system. Quadrupole mass spectrometer coupled to an electric furnace is applied to study the vaporisation behaviour of phosphorous gas phases from municipal solid waste (MSW) incinerator ash of sludge during solid-state reduction by carbon. Measurements are carried out in vacuum conditions of 2 x 10-6 Torrs and furnace temperature range 573 - 1773 K, at a heating rate of 7.22 K/minute. It has been found that most of the phosphorus is vaporised as PO2, P2 and P4, in agreement with thermodynamic estimation despite a shift in the temperature regimes.

Jan 1, 2006