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The Upper Waimangaroa mining permit is part of the Buller Coalfield and lies on the eastern side of the Stockton-Denniston Plateau. The mining permit area is estimated to contain a total in-ground coal resource of 58 million tonnes, contained within 13 separate coal resource .blocks. The coal is Bituminous High Volatile B rank with export potential as semi soft coking or thermal coal. The Northern Opencast mine is the first mine proposed for Upper Waimangaroa and consists of the three resource blocks at the northern end of the permit area. The highwall of the mine will cut into the Mt William Range resulting in overburden cover of up to 150 metres in some areas. The ability to rehabilitate the area after mining was a major consideration in the design of the mine. The Northern Opencast area has been geologically mapped, extensively drilled and effectively modelled using Vulcan software. Three distinct coal seams are present and the mineable in situ resource is estimated at 8.7 million tonnes of which approximately 7.1 million tonnes is likely to be recoverable. It is proposed that this resource will be mined using opencast methods and the void will be backfilled with overburden. The life of the mine is at this stage estimated at 19 years based on an annual production of 500,000 tonnes at 1.8% sulphur and the Upper Waimangaroacoal will be blended with low sulphur coal from the Greymouth Coalfield to meet export specifications. The Northern Opencast area contains a range of native flora and fauna and physical features which make it an environmentally significant area. Mining will totally modify the area, thus an effective rehabilitation scheme is an integral part of the mine plan. Various rehabilitation methods will be used, and wherever possible, the backfilled areas will be rehabilitated so as to resemble the original area as closely as possible.

Jan 1, 1998

By Edwards A. B

Occasional, sporadic and small occurrences of lollingite in the Broken Hill lode have been described,(l) mostly in the garnet sandstone in the foot-wall and under-wall of the Broken Hill lode. The lollingite contains appreciable percentages of cobalt and nickel and is regarded as an early mineral in the development of the lode; and, with the incoming of the sulphides, it has suffered considerable replacement by arsenopyrite. During the conversion of iron arsenide into the iron sulpho-arsenide, ilie nickel and most of the cobalt are removed in solution and are inferred to reappear in niccolite and other minerals that have been recorded among the later minerals of the Broken Hill lode. As a result of observations of the officers of ilie Broken Hill South Ltd., an occurrence of cobaltite can now be recorded which has developed by an analogous type of replacement.Cobaltite has previously been recorded from the Australian Broken Hill Consols lode in the vicinity of the rich deposits of silver, though not in contact with them. Cobaltite has been found in the northern extremity of the No. 2 lens of the Broken Hill lode at the 1,480 feet level of the Broken Hill South...

Jan 1, 1944

By R L. Brathwaite, S E. Belliss

Linear and semi-circular features were mapped in the volcanic terrain of the southernCoromandel Peninsula, North Island, using JERS-1 synthetic aperture radar (SAR), Landsat-4 Thematic Mapper, and SPOT-2 multispectral satellite data, digital elevation models, and aeromagnetic data. The mapped features typically correspond to recognised physiographic features and are thus a useful aid to mapping the structural trends in the region. Major linear features exhibit a strong N-S to NNE-SSW alignment, and lesser NW-SE and NE-SW trends. All these are superimposed on pervasive, closely spaced, NNE-SSW and NNW-SSE lineaments present over most of the hilly parts of the map area. There are few major E-W aligned features. Some alignment trends correspond to strike directions of veins in the epithermal gold-silver deposits of the region, but none of the known mineralised structures were visible on the remote sensing data.   The volcanic rocks are Late Cenozoic in age and include a variety of rock types: andesite and dacite flows, domes and tuff breccias, rhyolite domes, tuffs and tephra, lacustrine siltstones, and ignimbrites. Mapping of different textures in the SAR image failed to provide additional information on rock types to that derived from the Landsat and SPOT images. A simple discrimination of rock units based on radar texture is apparently prevented by the complex volcanic geology, superimposed hydrothermal alteration, and long period of erosion.

Jan 1, 1994

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

Before the arrival of the first Europeans, Aborigines living in the northern Flinders Ranges mined ochre - an earthy form of haematite used for pigment.The discovery of copper ore at Kapunda and Burra in the 1840s stimulated the early settlers to prospect further north along the ranges. Many of the new discoveries were not properly evaluated and companies were floated on the most tenuous evidence.

Jan 1, 1993

By G R. Ballantyne, M S. Powell, M Tiang

This paper reviews the proportion of energy attributable to comminution within the Australian gold and copper mining sector. The need for this is motivated by inconsistencies in the quoted energy usage data and the lack of a common basis for reporting the fraction of energy in mining that is attributable to comminution. This study should form a reliable basis from which to assess both demand and opportunities to reduce energy consumption.The proportion of milling energy was calculated for the major producers in the Australian gold and copper sector. A sampling methodology created by Powell et al (2003 - 2010) was initially used to provide an accurate and meaningful measure of the energy used in the comminution process. However, no useful method for grouping similar mines was found. Fortunately, a surprisingly large amount of high quality data was found from a number of different sources, allowing the development of robust relationships to be used to estimate a high proportion of the unknown values. The fraction of energy attributable to comminution was found to be dependent on how the total energy consumption was defined. For instance, comminution accounted for 52 per cent of the electrical energy, but only 21 per cent of the total energy publicly reported by the mines because a substantial proportion of energy used on a mine is in the form of transportation fuel (mostly diesel). Critically, the measured electrical energy consumption does not account for transmission and generation losses, while diesel energy usage is typically quoted according to its calorific value. This review proposes that diesel should instead be converted via the mechanical efficiency factor for diesel engines. Using this conversion, comminution was found to account for 36 per cent of the available energy on average. This approach allows a useful basis of comparison for mines regardless of whether milling energy is obtained from electrical or diesel generation. A summary of the results are shown in Figure 7 with other values obtained from literature. The total comminution energy assessed in this study accounts for 1.3 per cent of AustraliaÆs electricity consumption, this figure will increase as the other mineral commodities are added to the study.CITATION:Ballantyne, G R, Powell, M S and Tiang, M, 2012. Proportion of energy attributable to comminution, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 25-30 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By I Haine, J Penm, T Waring

During 1999 there was a considerable turnaround in world prices for most minerals and energy commodities, except for the bulk commodities (coal and iron ore). The main reasons for this turnaround were: improved prospects in demand for most minerals and energy commodities in the Asian region following a return to both economic and industrial production growth in key economies in that region; continued moderate growth in demand in Europe and North America; substantial production cutbacks in a range of minerals and energy industries; effective reductions in the supply of oil by OPEC nations; and an announcement by European central banks that they would cap the amount of gold they sell and loan in the next five years. Most of these influences are expected to be sustained into the first years of the new millennium. In 2000, with exception of coal, average world prices of minerals and metals are forecast to rise significantly. Gross domestic product and industrial production is expected to grow in some European countries and most Asian countries in 2000 and, with moderate growth expected to be sustained in the United States, demand for minerals and energy is expected to increase. AustraliaÆs main bulk commodities, iron ore and coal, saw prices set for 1999 - 2000 at substantially lower levels in negotiations in early-1999. Double digit price cuts were locked in. However, similar falls appear to have been avoided for coal in Japanese Fiscal Year 2001, while increases of between four and six per cent were achieved for iron ore. Forecast modest recovery in economic growth in Japan and increasing demand elsewhere in Asia are expected to lead to tighter market conditions in 2000. Beyond 2000, world minerals and energy markets will be influenced by the expected robust global supply responses of minerals and energy companies, against a background of sustained economic growth and industrial production growth in major consuming countries. Over the medium-term, a return to declining real prices which have been evident for most commodities in the recent past, is expected as exploration, mining and processing technological change and associated productivity growth continues to reduce industry costs. While lower rates of exploration and mining investment in Australia between 1998 and 2000 will modestly constrain the rate of future industry expansion, Australia remains an important contributor to expected growth in global minerals supply over the medium-term. Australian mine production is forecast to grow between 1999 - 2000 and 2004 - 05, boosted by production from recently commissioned mines and minerals processing facilities and comissioning of other projects at advanced stages of planning.

Jan 1, 2000

By R Crookes

Mine to Mill optimisation is not a recently developed concept. It is one which is finally gaining greater acceptance in the Australian Mining Industry, possibly as a consequence of the downturn in markets and certainly made possible by the development of tools and techniques to measure and predict performance of mining equipment and milling plants. Fragment size after blasting has a major bearing on the performance of all aspects of mining and a major influence on the economics of the mine and mill. The process to optimise fragmentation consists of identifying the key factors, measuring their sensitivity through a modelling and trialing program and conducting economic evaluations on the changes on both the mine and mill. Management of the Ernest Henry copper-gold mine in NorthernQueensland, Australia, has espoused the Mine-to-Mill concept and isactively pursuing excellence in blasting to drive down the total cost of mining. Ernest Henry has extremely hard, wet and heavily jointed geological conditions, and had high powder factors and a large percentage of oversize material reporting to the crusher or ROMstockpile. A blasting improvement program was undertaken betweenErnest Henry Mining, Thiess Contractors and Orica Explosives tooptimise the ore size distribution, particularly the oversize component, as a step to reducing production costs. Measures of success included bringing the rock breaker back from double shifts to part-time operation and increasing direct dumping into the crusher from 70 per cent to 92 per cent. Tools and technologies to predict and measure the performance ofindividual blasts are needed before it is possible to optimisefragmentation or the downstream processes. These include suchspecialised Orica Explosives tools as SABREX, POWERSIEVE, andPOWERLINE and commercially available drill monitors. As importantare the more common still and video camera, borehole loggers,measuring tapes, surveying equipment such as face profilers, and ahigh-speed camera if possible. There are many tools which can be applied however it is rarely necessary or possible to use all of them due to time constraints and a point of diminishing returns. The critical point is knowing what the true parameters of the blast were compared to design - only then can the predictive tools be effectively utilised. Stage one of the program has seen gradual improvement as theunderstanding grew and practices have been implemented resulting inreduced bridging in the crusher, geological mapping with respective blast designs and the oversize component under control. This paper is about a process approach which links tools and technology to understand the fragmentation drivers and then to optimising the size distribution.The continuous improvement program continues...

Jan 1, 2000

The Waimumu area, 12 km southwest of Gore, is underlain by the Gore Lignite Measures, an early Tertiary fluvial sequence approximately 500 m thick resting on Triassic-Jurassic argillitic basement. The Waimumu Quartz Gravels (Pliocene) have been deposited locally and are in part due to the localised reworking of the Gore Lignite Measures. Structurally the area is dominated by the Dunsdale Fault System, a steeply dipping series of NE trending reverse faults (Isaac and Lindqvist, 1990). The Belle-Brook, Hedgehope and Parker Road sites sampled are adjacent to the downthrown (east) side of the Hedgehope Fault.The authigenic gold-sulphide association at Belle-Brook was discovered in 1987 (Falconer, 1987: Clough and Craw, 1989). Despite a very limited amount of alluvial mining a significant quantity of authigenic marcasite has developed. Authigenic sulphide trace element analysis has shown anomalous amounts of As, Ni, Cr and to a lesser extent Zn, Pb and eu (Table 1). It has been established that the nickel occurs as a colloform banded Ni sulphide, possibly bravoite, within the marcasite (Figures 1 & 2). Arsenic and nickel (re)mobilisation are well documented in the literature. Generally As and heavy metals are mobilised in the groundwater as a result of the oxidation of sulphides (ie as a result of mining). At Belle-Brook it is reasonable to assume the authigenic sulphide trace element composition reflects either localised groundwater contamination or hydrothermal mineralisation. This poster presents some preliminary findings.

Jan 1, 2001

This paper provides an expanded definition of industrial minerals that challenges the way we look at exploration, development and the understanding of mineral industry structure and profitability. Included in industrial minerals are bulk commodities such as iron ore and coal alongside the more traditional industrial minerals such as salt, soda ash, silica sand and clay. The profitability of industrial minerals is reviewed from a producerÆs perspective and shown in many instances to be significantly higher than for precious and base metal industries. The key drivers of profitability are examined along with some highly profitable industrial mineral industries such as borate, potash, chromite and natural soda ash. Demand for industrial minerals in Australia and Asia is reviewed, with a focus on supply bottlenecks and the opportunity this represents for investment by Australian companies. The establishment of new price benchmarks is considered and the possibility of new export grades for industrial mineral products. Investment opportunities in industrial mineral projects are outlined, including some exploration concepts in Australia and Asia. Industrial mineral project evaluation methods are discussed and the challenge issued to companies (exploration, production and finance) to become a part of the profitable action in the world of industrial minerals.

Jan 1, 2004

By Griffin PT, Espinosa-Gomez R, Jameson GJ

Two major issues are to be addressed in the Copper Concentrator of Mount Isa Mines Limited. The first of these is the need to increase concentrator flotation capacity to increase copper recovery, while the second is the need to reduce the iron sulphide dilution to meet future smelting requirements. Extra capacity in the cleaner and retreatment sections of the concentrator have been identified as key target areas, with additional copper recovery of at least one per cent identified from plant trials. Extensive pilot plant tests have been undertaken to evaluate the performance of the Jameson cell compared to conventional mechanical cell and column circuits. This work has shown that Jameson cells present an opportunity to achieve the desired grade and capacity specifications at lower capital cost than available alternatives. This paper outlines metallurgical results of work undertaken in the Copper Concentrator, together with a summary of pertinent Jameson cell operating parameters investigated during the period.

Jan 1, 1993

The great philosopher, Marshall McLuhan, is said to have stated that the use of forecasting as a means of guiding future actions is akin to driving an automobile through observations made in the rear-view mirror! In effect, in forecasting it is assumed that there will be an orderly progression from the past into the future, and that the model will be sufficiently unvarying for use to gauge both the directions and the rates of change. The concepts of forecasting have served man well in disciplines in which the relationship between causes and effects can be clearly demonstrated; such as between rainfall and crop yield, for example. These are of no value, however, when conditions change rapidly and unpredictably, or when there is no model at all. Even worse, under such circumstances our preconceived notions may cause us to make some horrendous errors in judgement. Such are the risks at present in attempting to make an assessment of the educational needs of the minerals industry for the coming century! The model, and the conceptions that we have had of the linkages between cause and effect are in disarray. Minerals markets are chaotic, and there is almost no ability to forecast trends in metal values. Linkages between supply and demand seem tenuous. Internationally, producers are struggling for survival. Mine closures, temporary shutdowns, and reopenings are frequent occurrences. Decision-making under uncertainty is probably one of the most certain things about the world mining industry Today!

Jan 1, 1986

The construction of the pipeline was completed in June 1956 and the line placed into operation in December 1956, ie. it has now been in continuous operation for approximately three years under an operating pressure of up to 350 lb. p.s.i.In reviewing the operating experiences of the line we must consider three major factors, which are:(a) The effectiveness to date of the protective methods for prevention of corrosion of the pipeline, ie. the preservation of the asset.(b) The maintenance of the line in regard to interference as to its stability which could be occasioned by erosion of the line, land-slides, accidental interference by the public, or construction authorities, etc.(c) The operating techniques employed.PROTECTIVE METHODS OF THE PIPELINESo to permit a clearer appreciation of the effectiveness of the protection of the! steel pipe against corrosion, I will briefly describe the methods used in the construction of the line.The line, which is 18 in. O.D. by %6 in. thickness steel pipe, is located approximately It miles south of the main Melbourne/Gippsland electrified railway.The steel from which the pipe was manufactured conforms to ASA.A33-1937 with the following modifications.Minimum elongation on a 2 in. test specimen...

Jan 1, 1960

By Read T. A

THE Broken Hill South Ltd. is one of ten companies operating on the Broken Hill lode (See Fig. 1). It has two leases-Blocks 7 and 8-of a total length of 2250 ft. on strike of lode.From the surface to 425-ft. level the ore was found principally in the form of carbonates and high-grade friable sulphides. Below the 425-ft. level the ore is found in the form of compact sulphides. The ore-bodies found in the South mine may be broadly divided into two classes...

Jan 1, 1921

This paper describes the MillMapper technology developed for condition monitoring of liners and other operational parameters in grinding mills used for mineral comminution, by presenting a case study of its application. MillMapper provides maintenance engineers, operations managers and process and plant metallurgists with quantitative, accurate and reliable condition monitoring data for informed decision making regarding the maintenance and metallurgical aspects of such mills. MillMapper uses calibrated laser scanners for the capture of three-dimensional surface representations inside a mill during a shutdown so as to determine shell, feed and discharge liner thickness at a resolution of several million data points, a procedure that nominally takes five minutes to complete. Once several data sets over time have been collected inside a mill, MillMapper can be used for liner wear, liner wear zone, liner weight, ball charge volume, ball charge weight and intelligent profile tracking over time. Liner tracking in combination with site defined reline and failure criteria and with throughput tonnage data is utilised for change out prediction of each separate liner segment type.

Jan 1, 2008

In making any attempts to determine the depositional environments in which coal seams accumulated it would be useful to establish whether there is a pattern, or patterns, of development which the majority of the seams have followed. To this end, the distribution of types of coal seam sequences found in the standard petrographic profiles of about a hundred Australian coal seams of Permian and Triassic age has been examined statistically, using the "chi square test" with the limiting probability set at O·Gl.Results indicate that non-random conditions have probably prevailed during the deposition of most of the seams. More samples are needed for conclusive results.The plants, or some other internal feature of the swamp environment, have been the important controlling factor in the development of the seam sequences.Comparison has been made with some British Carboniferous coals.

Jan 1, 1972

By M P. Schwarz

This paper describes modelling studies of the flotation cells used by BHP Billiton Nickel West Ltd in the slimes circuit at Mt Keith. The aim is to achieve a better understanding of the hydrodynamic limitations in the existing cells to improve nickel recovery. Computational fluid dynamics (CFD) simulations have been performed on the 100 m3 mechanically-stirred cells. The data produced by the simulations include velocity vectors, gas holdup distribution, solids distribution, bubble size, superficial gas velocity and turbulent parameters. These results have been checked and found to match hydrodynamic measurements at the plant. An analysis of the data found that one of the limitations in fine particle recovery was related to the air bubbles discharged with the tailing. The air in the discharge was caused by the high viscosity of the pulp. In the presence of fine particles, the pulp exhibits high viscosity with a yield stress. The increased drag due to high viscosity caused the bubbles to rise more slowly up the cell. This results in a significant hold-up of bubbles, some of which report to the tailing with associated loss of valuable minerals. A parametric CFD study of the operating variables shows that less air would be discharged in the tailing by decreasing the following: air flow rate,pulp density,stirring speed, andfrother addition. Simulation results indicate that these changes would cause a lowering of the air hold up in the cell especially near the discharge area. Predictions of the bubble-particle attachment rates under various operating conditions have also been calculated. Although it is possible to increase attachment rates by increasing stirring speed or by increasing pulp density, the amount of air discharged and the amount of nickel loss through the tailing will also increase. The project showed that CFD modelling is a powerful tool for studying hydrodynamic effects of bubble-particle interactions in flotation cells.

Jan 1, 2008

By P F. Lauricella, D Hendri

In the Mesel sediment-hosted disseminated gold deposit, the spatial distribution of hydrothermal alteration is controlled by steeply dipping faults and shallowly dipping lithologies. Hydrothermal alteration of carbonate rock is characterised by decalcification, dolomitisation and silicification. Intense argillic alteration occurs in a laccolithic andesite intrusion adjacent to decalcified and silicified carbonate units. Sulphide minerals (pyrite, realgar, orpiment, stibnite and cinnabar) accompany hydrothermal alteration and precious metal mineralisation. The trace elements Ag, As, Sb and Hg are zoned spatially throughout the deposit. Mesel contains a mineable gold reserve of 7.8 million tonnes at 7.3 g/t Au. Gold mineralisation is preferentially localised in carbonate rocks adjacent to and beneath the andesite intrusion. The ore body consists of a central, near-vertical, high grade 'feeder' system flanked by tabular, inward dipping, moderate grade 'ouflow' zones. Mineralisation is controlled predominantly by two steeply dipping faults with high grade (=10 g/t) gold zones centred about structural intersections and fault splays. Gold is submicron size and locked in very fine grained (<10 microns), disseminated and fracture-controlled arsenical pyrite. The Mesel deposit developed where high angle faults guided ascending, sulphidising fluids into reactive carbonate stratigraphy adjacent to and beneath the andesite intrusion and during subsequent migration of the auriferous fluids along 'outflow' channels. Early decalcification and dolomitisation enhanced porosity and permeability prior to silicification and sulphidation. Gold deposition occurred late in the genesis of the deposit.

Jan 1, 1995

The Ramu chromite deposit occurs in the Marum Ophiolite complex and is the most economically attractive chrom-ite deposit in Papua New Guinea. Its lateritic nickel, chromite and cobalt potential has attracted several compan-ies to prospect the deposit.In the present work, the compositions of chromite in the Ramu lateritic deposit and coexisting olivine-chromite pairs in Marum Ophiolite dunite were analysed with the electron microprobe for Fe, Mg, Cr and Al. The results were used to determine the relationship between the cations in the tetrahedral and octahedral structures of the chromite. In addition, the Fe, Mg, Cr and Al cations of the coexisting olivine-chromite pairs were used to calculate the equilibrated temperatures of crystallisation of the chromite. The variation of Fe", Mg and Cr cation values of the chromite in relation to the calculated temperatures was studied by regression analysis.

Jan 1, 1994

By McKenzie A. M

The Corridor ore body is so named because it occurs in an east-west zone or corridor of schist bounded on the north by the siliceous conglomerates of Mount Lyell, and on the south by similar conglomerates of the Tharsis ridge (Fig. 1). It was discovered after the geophysical prospecting methods described below had defined a target zone for diamond drilling.Since the proving of copper mineralisation by drilling, the corridor orebody has served the vital function of a convenient known target body for the orientation of more recently developed geophysical methods. Traversing of the orebody by these new methods has provided experience for the evaluation of anomalies elsewhere.Some of the methods applied had not been used in Australia before, and were introduced to the west coast of Tasmania through the undertaking there of modern regional exploration programmes. The authors feel that the information gained could be of assistance to others engaged in geophysical prospecting.HISTORY OF DISCOVERYProspecting in the Mount Lyell district has been more or less continuous since 1881. The first geological report was published by Thureau (1886).In 1934, Blazey and Douglas (1934-38) commenced geophysical surveys at Mt. Lyell using the equipotential method.They obtained anomalous indications in several discrete zones and actually detected the south-east half of the corridor orebody but their work never became the basis for...

Jan 1, 1961