Search Documents

Every estimate of ore reserves necessarily contains an assumption in regard to the specific gravity of the ore. This assumed figure may be based on experimental data, on textbook data, or on a reconciliation of past tonnage estimates and production figures. Not infrequently it is simply a guess - shrewd or otherwise.Errors in the density factor are not likely to be serious in gold-quartz mines-or, at least, not so serious as in base metal mines. It is to the closer determination of ore density in the latter that this paper is devoted. Moreover, the remarks apply to ores which show no appreciable pore space.Not many ore bodies are sufficiently homogeneous to allow of a truly representative factor being obtained by the simple testing of a few specimens of ore, or by the weighing, after breaking, of a carefully measured block. The empirical figure derived from a comparison of past ore reserves and actual production can never truly describe conditions other than those now past; no real link with ore as yet unmined is provided. The dilution of heavy ore by waste is not exposed by this method, but is effectively cloaked. Anyerrors in past estimations of ore reserves are transmitted, by way of the density factor, as a source of error in all future estimates.ObjectIons may be raised to the practice of weighing measured blocks of ore in the case of any but a very homogeneous ore body. Even then, the exact composition of the block weighed, and an indication of whether its moisture content is representative of the whole, are difficult to determine.

Jan 1, 1940

Builders have been very familiar with iron since ancient times, but because of its weathering characteristics it was relegated to use as a fastening material in unexposed places and bronze became the popular metal for exposed applications. It is of interest that iron nails buried deeply about A.D. 87 at a Roman fortress and carefully covered with clean beaten earth under conditions practically excluding oxygen were found to be almost unrusted 1870 years later. (1) Today, weathering steels, which contain less than 2% of alloying additions, can be used in exposed situations without protection and without experiencing continuous wastage. As we all know the steady access of atmospheric oxygen to the surface of plain steel causes continuous corrosion. Weathering steels, on the other hand, due to their alloying additions develop their own impervious surface layer which limits the access of atmospheric oxygen and effectively limits corrosion. Table 1 shows the chemical composition of a plain carbon steel and a typical weathering steel. Fig. 1 shows what we refer to as direct corrosion - time curves in which corrosion loss is plotted against time of exposure in an strial environment. The weathering steel has a high rate initially which then decreases steadily for about three years, as the stable rust film builds up. This is followed by a practically linear relation where the very low corrosion rate, according to one school (2), is due to a blocking of the rust pores by insoluble complex salts formed from interaction of the oxidation products of the separate alloying elements. The start of the linear region represents a total corrosion loss of only about 2 thousandths of an inch.

Jan 1, 1970

By S Hapugoda, H Han, L Lu

Sinter quality depends heavily on the mineral phases, textures and physical structure of the sinter, which are formed upon solidification of the sinter melt. The interaction of sinter initial melt with its surrounding materials will impact the properties of the sinter melt and consequently the solidified structure and quality of resultant sinter. Spreading and penetration are two important phenomena dictating the interaction of the initial melt with its surrounding materials, such as nuclei and adhering fines. In the present study, the penetration behaviour of an initial melt into various natural iron ore substrates of different ore types during sintering was studied using a laboratory scale penetration testing procedure. The penetration depth and width were found to increase with temperature and vary with the type of iron ore due to their unique pore structure and mineralogical texture.

Nov 8, 2021

The geotechnical factors controlling the design of the open pit slopes of the Pasminco Century Mine near Lawn Hill, Queensland are presented below. Pasminco Century is a stratiform shale hosted zinc deposit in the Lawn Hill Formation that is overlain in part by the Thorntonia Limestone Formation. Both the mineralisation and overburden is located within a competent rock mass such that intact rock strength and discontinuity spacing is generally sufficient to prevent large-scale slope failure by breakage through the rock mass. Rather, overall slope stability issues are dominated by the major discontinuities within the rock mass. The deposit is located in a structurally complex regime, it consists of a synclinal basin which is truncated by easterly striking normal faults through its centre and northern and southern limits and by an unconformity on its eastern and western margins. Deposit geometry and slope stability is further complicated by small-scale folding, a pattern of northeast and southeast striking subvertical faults and north easterly dipping thrust faults with their associated fault emplaced blocks of Lawn Hill Formation in the overburden. The large size of the deposit requires a staged mining approach with the excavation of both final pit walls around the external sides of each stage and interim pit walls along the internal boundaries between adjacent stages. The deposit geometry and major discontinuities control not only the final pit wall design but also interim wall location and orientation, excavation sequence and in some stages the excavation schedule. Two and three-dimensional limit equilibrium stability analyses were conducted using both deterministic and probabilistic approaches to determine appropriate pit wall design criteria and to select a suitable excavation sequence and schedule.

Jan 1, 2000

Chile, which hosts around 30 per cent of the worldÆs copper resources, is now the largest producer and exporter of copper. Chilean copper output accounts for more than one-quarter of total worldwide production. An increase to around 40 per cent is forecast by the end of the century. In addition, Chile ranks eighth in silver production and 11th in gold output. In Chile, mining generates more than eight per cent of the countryÆs GDP and the total value of mineral exports is more than US $7.85 billion corresponding to more than 25 per cent of South AmericaÆs mineral production. The rate of growth of Chilean mineral production is indeed impressive. Table 1 shows that in the period 1969 - 1998, copper annual production increased 564 per cent from 667 000 t to 3 764 000 t. Gold production went up 27 times from 1827 to 49 770 kg. Silver output grew 1219 per cent from 95 650 kg produced in 1969 to 1 166 380 kg in 1998. Several facts explain this dramatic increase of production, but the most important was the success of exploration sustained over the same period. This resulted in the discovery of several world-class deposits which when developed into mines, account for much of the production increases. Therefore, this summary review shows the success of basic exploration carried out during the last 30 years in the Chilean territory. The review is based on data already published in different specialised mining books or magazines. It only includes those world-class discoveries not the lesser discoveries important at local scale. All figures were calculated using 1998 $US dollar and average estimated metal prices valid for 1999: copper $US 1653 per t ($US 0.75 per pound), gold $US 9452 per kg ($US 294 per ounce) and silver $US 177 per kg ($US 5.5 per ounce).

Jan 1, 1999

By R L. Koenig

Previous papers at Metplant conferences have covered the options for crushing and grinding circuit selection. High Pressure Grinding Rolls (HPGR) may have considerable advantages over autogenous milling circuits but test work and evaluating different grinding circuits must be done to establish which circuit provides the best option. The Hawsons low grade magnetite project provides a specific example in using thorough test work, careful simulations and detail in design to allow the evaluation of grinding circuit performance. Fortunately tools are available for this evaluation and the test work for the Hawsons iron ore is detailed in this paper. The results of the test work and simulation indicates that although the Hawsons iron ore is competent in terms of autogenous milling given the medium hardness of the ore in the Drop Tests, the HPGR testing indicates that the use of HPGR is likely to use half the energy requirement. This is a characteristic of the Hawsons iron ore and is likely to be valid for other iron ores in the Braemer Iron Formation which stretches from the Hawsons lease in New South Wales to Razor Back and South Dam in South Australia. The Hawsons magnetite iron ore resource has been known from the early 1960s when CRA explored the area. However, the Pilbara region was discovered in this era and this led to development of high grade direct shipping grade hematite ores. Carpentaria Exploration (Capex) rediscovered the magnetite whilst undertaking multi-commodity exploration in the Broken Hill district during 2009. The magnetite grade was found to be low at around 16% Davis Tube mass recovery (DTR) but despite this, the project provides a positive business case as a result of the following key factors:• The mineralisation is particularly soft for crushing and grinding with a Bond Work Index of 6.3.• The mineralised rock fractures easily preferentially along grain boundaries.• The location is close to mining infrastructure and a skilled workforce in Broken Hill, 60km to the North East.• It is close to road and rail infrastructure for access to the resource.• The only contaminant in concentrate is silica.• The resource contains many billions of tonnes of magnetite mineralisation.The low Bond Work index is a key characteristic of the Hawsons iron ore and the use of autogenous milling and HPGR circuits is compared to other iron ores indicating why the plant energy requirement may be just as important as iron ore grades.

Aug 8, 2011

By G R. Hancock

A common and cost-effective method for post-mining landscapes is to construct linear hillslopes with a break in the hillslope at appropriate distances to reduce hillslope length and resultant erosion risk (Figure 1). The break in slope occurs at a point that has been found by local experience to be appropriate for the materials and climate. Further enhancement of the linear hillslope may be assisted by surface treatment such as ripping (Saynor, Lowry and Boyden, 2019) (Figure 1). Firstly, ripping introduces surface roughness which breaks up flow paths reducing flow velocity thereby reducing erosion potential. The depression produced by the ripping acts as a trap which captures water, sediment and organic matter

Aug 2, 2023

By H Bleuler

A new portal and access drift was constructed by Concrete Constructions for BHPÆs Elouera Colliery, south of Wollongong.The portal area at the base of the Illawarra Escarpment is in soft colluvium material, underlain by highly to moderately weathered sandstone. The area has a well documented history of slope movement or slope creep and one of the main criteria for the design was to minimise disturbance to the unstable slope by limiting the excavation for the portal establishment. This was achieved by incorporating a sloped headwall and gabion wingwalls to accommodate the anticipated creep and groundwater seepage.Main features of the design process also included the provision of both primary and secondary support in a single shell application and the use of canopy tubes to provide support ahead of the tunnel face.The active involvement of the designer during the construction phase and the flexibility of the design concept allowed changes to the support methodology to be carried out as excavation proceeded.This paper describes the design process undertaken for portal establishment and access drift to cater for the variability of the exposed ground conditions along the drift alignment.

Jan 1, 1999

Hydraulic backfill is generally retained in stopes using permeable barricades. Mitchell et al (1975), Mitchell (1992) and Grice (1989) have shown that under normal drainage conditions, barricades experience low levels of loading. Cowling et al (1988) have also shown that barricades are susceptible to piping failures if excess water has ponded on the upper backfill surface and if leakage of backfill from the barricades has occurred. During 1997, six hydraulic backfill barricades failed in four different Australian mines. Fortunately, in each case, the quantity of backfill slurry released was small, and no injuries to personnel nor damage occurred. Detailed investigation of two of the incidents showed that the primary cause of failure could be attributed to the delivery of excess quantities of transport water from the low-density slurry. For each of the incidents investigated there was evidence of the development of piping failures, which resulted in hydrostatic loading conditions on the barricades from the ponded water on the upper backfill surface. The circular failure surfaces in the barricades were characteristic of the application of point loading conditions. This paper discusses the circumstances that led to these incidents and analyses the modes of failure. The standards for the safe operating of hydraulic backfill systems are reviewed along with requirements for ongoing management and control. The design requirements of barricade construction are analysed and some appropriate guidelines introduced.

Jan 1, 1998

Just as Australia is part of the Pacific Rim, so the Pacific Rim should be viewed as part of the whole world. That applies in particular to that scarce commodity û money. There are five main factors of production in any mining development û mineralisation, materials, manpower, management and money. LetÆs focus on the upstream input û mineralisation, and the downstream input û money, especially in the area of communications. Unknown to many, the Competent Person reporting on Mineral Resources and Mineral Reserves has a direct and unavoidable impact on the companyÆs financial statements û the profit and loss account and balance sheet. With respect to reporting of the major asset of most mining companies û the resources/reserves û investors are getting a better deal now than at any time in memory as regards flow and adequacy of information. Australia has been a world leader in this regard. The outlook is for even more informative and useful reporting. The more rigorous reporting requirements for Exploration Results and Mineral Resources/Reserves, which have become a worldwide phenomenon over the last five years, will continue. This will be positive for the mining industry as a whole and for Australia in particular. However competition for the scarce investment dollar will also increase. Put simply, mining has many competitors, unconnected with mining, for the capture of the investment dollar. It behoves all participants to recognise that there are three investment factors which influence strongly the willingness of investors to put money into mining. These are Confidence, Credibility and Consistency. AustraliaÆs investment image stands high in these three respects, but the competition will continue to grow. AustraliaÆs lead must be maintained. However, some investment decisions should not necessarily be based on fundamental, quantifiable facors. Some of these are outlined.

Jan 1, 2004

The following thesis is an outcome of an investigation undertaken by the writer, at the suggestion of Professor Skeats, of the dykes and associated auriferous reefs of the Walhalla-Wood's Point belt, with the view of determining what relation, if any, existed between the petrological nature and the extent of llietasomatic alteration undergone by the dykes, and the genesis and localization of the gold.Although the greater part of the writer's time in the field and laboratory was occupied in studying the dykes and auriferous occurrences, a study was also made of the general geology as a basis for the special investigation. In addition, it soon became evident in the field that secondary enrichment had played a marked part in re-concentrating the gold and some interesting data in this connection have been collected. For example, indubitable evidence has been found of nuggets of gold having been formed by secondary processes.

Jan 1, 1920

It is recognised by the current JORC (1999) code that resource classification involves the interaction of numerous qualitative and quantitative criteria such as data quality, geological continuity and grade continuity. No prescribed criteria and rules will work for all situations or even between different ore types within the same deposit. Also these criteria and rules are sometimes applied without a clear understanding of their appropriateness, accuracy or correct implementation. For these reasons case studies are useful to evaluate and compare criteria commonly used to assist in resource classification. In this paper blasthole data from a selected area of Joffre Member hosted ore of the Brockman Iron Formation at the Mt Whaleback orebody are used as the basis of a case study for the above-mentioned purposes. Iron grade, in per cent, is interpolated from a blasthole dataset into a block model using ordinary kriging. Samples are then removed from this blasthole dataset to produce a random sample grid, a semi-random sample grid and a regular sample grid. Using nearest neighbour, inverse distance squared, ordinary kriging and sequential gaussian simulation, block iron grades are estimated using these three blasthole data subsets as inputs. This provides four groups of estimates with the ordinary kriging estimate based on the complete blasthole dataset being considered to represent the true estimate of iron grades. Also generated during this process are estimates of the error for each block. These error estimates range from the simple, such as drill spacing, through to more advanced methodologies such as kriging efficiency and simulation. These estimates of grade and grade estimation error are then compared to the true estimate using graphs and statistics. In order of increasing accuracy the block grade estimation and simulation methods were nearest neighbour, inverse distance weighting, ordinary kriging and finally conditional simulation. The simulation in some instances doubled the accuracy of individual block grade estimates when compared to nearest neighbour and inverse distance weighting estimates. It was found that many methodologies for estimating the error of individual blocks performed equally well with only methods such as average drill hole spacing and classification by search ellipse pass number performing poorly. An approach on how to convert the abovementioned error estimates of individual blocks into a meaningful JORC classification is also discussed. Although advanced non-linear resource estimates are applicable, most iron ore mines are still using relatively straightforward methods. The use of blasthole data and some simple linear interpolation methods and simple linear based error estimates makes this study repeatable for most iron ore sites and their resource geologists. This style of investigation is recommended as a useful approach for the Competent Person to apply to their deposit and thus better select, implement and understand the criteria used for resource classification and provide more consistency and confidence in the resource classification process.

Jan 1, 2002

By A J. Clough

There has been an unprecedented rise in the fatality rate in the Australian mining industry over the last few years. The factors behind this rise are not clear; however, it is noted that the increase in fatalities has occurred during a fall in commodity prices.This paper examines prevention methods and systems to deal with hazards that have the potential to result in either single or multiple fatalities. Managing the risks associated with mine ventilation is used to illustrate the principals behind the approach.The paper also touches on the broad science of human error and proposes a multifaceted approach to controlling and preventing fatal risks.A summary of the steps involved in developing an effective principal hazard management plan is provided.CITATION:Clough, A J, 2015. Ensuring an effective principal hazard management plan, in Proceedings The Australian Mine Ventilation Conference, pp 3–8 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By J Player

Big Bell Mine started experiencing relatively large mining related seismic events, and accompanying rockbursts, from February 1999. Twelve rockbursts damaged access development from February 1999 to June 2000, with severe damage extending for up to 100 m along footwall drives. Five seismic events associated with the rockbursts were recorded by the AGSO, measuring 1.9, 2.2, 1.7, 2.4 and 2.2 on the Richter scale. These events affected 485 and 460 footwall drives in August and November 1999 and 535 footwall drive in June 2000 (drive level nomenclature is equivalent to the depth below surface and RL). After the third event (July 1999) it was apparent that the seismicity was not a once-off phenomenon. This (sudden) onset of seismicity required management to implement a series of precautionary measures:to ensure the safety of the workforce, to maintain continuity of production, and to reduce rockburst damage rehabilitation. The measures included extended re-entry periods and exclusion zones in high-risk areas, improved rockburst resistant support systems in areas prone to damaging seismic activity and improved support systems in areas prone to shakedown damage. A full-scale minewide ISS seismic system was ordered in October 1999 and commissioned in February 2000. A portable eight-channel CSIR-Miningtek system was installed at short notice as an interim measure in August 1999. This CSIR system covered the northern producing stopes, where the majority of the rockbursts had occurred. The objective of the seismic monitoring was to monitor relative activity and to determine trends with regards to time and location. MAP3D numerical modelling was used to investigate the relationship between seismicity and various combinations of stress components to assess the relative seismic risk in both current and proposed working areas. This information is used to determine where and at what stage in the mining cycle the rockburst resistant support is required. Analysis of the seismicity has determined two distinct modes of seismicity û small-scale localised, high frequency events in high stress areas and larger events related to shear along previously intact foliation surfaces. This paper includes a summary of the seismic history, seismic data analysis, support system design, mine design adjustments and management action to minimise the effects of seismic activity at Big Bell Mine.

Jan 1, 2000

The paper gives details of the reasons why attention was directed towards the modification of flotation cells. The cell volume and impeller speeds were reduced, and it is estimated that the power consumption for lead and zinc flotation will be reduced by about 2·8 kWh per ton of ore treated, and that substantial savings will be made in maintenance costs. The metallurgical efficien.cy of the operation has been maintained and attention is now being directed towards the improvement of grades of concentrates and recoveries of metals.INTRODUCTIONIt was on 1st August, 1934, that the first Denver No. 21 flotation cells were operated in the treatment plant of The Zinc Corporation Limited, in a pilot Nant which had been installed to determine the economics of all-flotation as against the then existing gravity and flotation practice.The ore being mined at that time came from the lead lode which consists of a granular mixture of galena, marmatite, chalcopyrite, tetrahedrite, pyrrhotite, pyrite and lollingite with a gangue association of calcite, quartz, bustamite, rhodonite, manganhedenbergite, garnet, fluorite, manganocalcite and apatite. The silver content of the ore occurs in three minerals-tetrahedrite, dyscrasite and pyrargyrite, the last two mentioned occurring in microscopic association only.A parallel lode, known as the zinc lode, was well developed at that time. The common lead lode gangue minerals-calcite, rhodonite, bustamite-were rare in the underground exposures of the zinc lode. No metallurgical work was done on this ore during the pilot plant operations although since then both lead and zinc lode ore have been treated.Early in 1936 plans were made for the complete re-organization of the mine operations, and in view of the metal-

Jan 1, 1956

By M Donatelli, E Grazio, A Heissenberger

The distribution of a contaminant in a bulk mass greatly influences the effectiveness of sampling procedures. Most currently used sampling guidelines for genetically modified organisms (GMO) testing have stringent distribution requirements. Specifically, all these protocols are based upon the assumption that GM material, if present, is randomly distributed. Yet, assuming randomness is risky because the applied sampling plan may not provide an accurate estimate of the content of the contaminant. Despite the general consensus that an evaluation of the possibility of non-random distribution of GM materials within lots is a pre-requisite for the definition of effective sampling protocols, no experimental data on the distribution of GMOs in kernel lots are available anywhere in the world. Additionally, to date there is no distribution-free statistical model to estimate sampling errors, thus making the theoretical definition of optimal sampling technique impossible when randomness cannot be assumed. Here we present preliminary results of the KeLDA project, which is the first study investigating the distribution of GM materials in large soybean lots imported within the European Union. The extensive variability of GM content, observable both within and among soybean lots, indicates that heterogeneity issues cannot be overlooked when defining sampling strategies for large lots of particulate material and that randomness cannot be assumed a priori. A new statistical model free from any distribution assumptions, developed in order to estimate the sampling error associated with different sampling protocols together with the risk of false-negative results, is also presented. The new model, which is applicable to any consignment of particulate material with respect to any kind of contamination, presents two novelties: first, freedom from any distribution assumption; second, the possibility of estimating the magnitude of the sampling error associated with different sampling protocols as a function of specific distributional properties.

Jan 1, 2005

By Howard G. L

The gold treatment plant of Great Western Consolidated N.L. is at Bullfinch, Western Australia, 22 miles north of Southern Cross, which is 100 miles west of Kalgoorlie. A railway to Southern Cross connects the mine with the main Perth-Kalgoorlie line.The plant, which commenced operations on the 31st October, 1952, was, designed by Messrs. Alex: Stewart & Co. in consultation with the technical staff of Western Mining Corporation Ltd. to treat 1,000 long tons a day, made up of approximately equal parts of quarry oxidized ore and underground sulphide ore, by moderately coarse grinding (2-3 per cent plus 65 mesh Tyler) and straight cyanidation without straking. The design had to allow for future treatment of all sulphide ore at the rate of 40,000 tons per 28-day periodand to make provision for the possible later inclusion of preaeration treatment.The test work on .which design was based was done on representative development samples, the mine being divided into zones for this purpose, to check possible local variations from average treatment behaviour. Proposed mill feed mixtures were made up from time to time for complete ore dressing tests, which were conducted in the Western Mining Corporation laboratory at Kalgoorlie.The chief feature of the design was that the plant had to handle the extremes of very soft, poor settling and filtering oxidized ore and very hard, good settling and filtering sulphide ore. On one hand, crushers and mills had to be large enough to handle the sulphide ore and on the other, thickeners and filters had to be large enough to handle the oxidized ores.The design is marked by simplicity, the use of large units of equipment, and flexibility to cope with a variety of ores.

Jan 1, 1956

By G Chitombo, G Lewis

The knowledge of the expected run of mine (ROM) fragmentation during the feasibility study of a green field site is essential for the design of downstream crushing and milling processes. However,the prediction of blast fragmentation can be a challenging process due to the uncertainty related to the blast design and rock mass parameters. In general,a number of possible blast designs are considered in a feasibility study,with factors such as bench height and blasthole diameter influencing the design. Rock mass parameters are normally derived from a limited number of geotechnical diamond drill cores. Although diamond drill core can provide detailed information concerning intact rock strength (unconfined compressive strength and point load),it provides limited structural information to predict the in situ block size distribution of the rock mass. The in situ block size is an essential input to the prediction of the fragmentation distribution, in particular the coarse end. This paper outlines the methodology of blast fragmentation modeling undertaken for a green field feasibility study at the Riska gold deposit in Indonesia. The favoured milling process for the feasibility study was dump leaching,with no crushing of the ore material extracted from the pit. For this reason,blast fragmentation was a critical issue to be addressed by the study. A range of blast designs were considered with bench heights and blasthole diameters ranging from 4 m to 7 m and 76 mm to 102 mm respectively. Rock mass data was obtained from 19 diamond drill cores across the deposit (total drill length approximately 2200 m). Intact rock strength was estimated from qualitative strength descriptors,while the in situ block size distribution of the rock mass was estimated from the Rock Quality Designation (RQD) of the core. The methodology of fragmentation prediction involved a number of steps including the estimation of rock mass parameters from diamond drillhole data including the estimation of the in situ block size, delineation of blast domains within the deposit,and the assessment of the impact of various blast design parameters and rock mass variation on the predicted fragmentation distribution. The modelling process for the Riska green field site highlighted the need for additional rock mass data to be collected post feasibility stage and once the development of the mine commenced.

Jan 1, 2004

The æProfit Driver ModelÆ is a tool which builds costs from first principles and integrates revenue, costs and physical mining parameters and, hence, can quantify the impact and leverage on profit. In this paper an æexample mineÆ has been created to represent a typical Australian Open Cut Coal Mine. This has then been input into the Profit Driver Model to allow different variables to be tested. A series of variables were tested to determine which ones had the highest impact on profit and results are useful to management as a guide to the areas in which they can focus effort to achieve better profitability. Whilst the highest profit drivers are those external to the control of management and include selling price and exchange rate, the next most sensitive are those variables related to the geology of the mine and the mining method. These included coal quality, yield and strip ratio. Site management has some control of these. For example, the ability to vary the sequence of mining or improve the yield by a more efficient coal washing process. The efficiency of the workforce and management has similar impact to the mining variables. Finally, there are the supply variables, such as fuel, labour and explosives which are the least sensitive although, cumulatively, still significant. Each mine is different and the results of the example mine will not apply to all mines. However, the approach taken is universal and the tool illustrates a simple method to quantify the profit impact when changing variables. The benefit of the approach is the short time taken to get a set of results. This allows the more detailed and time consuming work to be more focused. The results illustrate that management has a significant influence on profitability.

Jan 1, 2000

COAL constitutes such a gigantic item in modern industry, either for direct heating, production of coke for smelting, or for the generation of power, that its quality and price play a very significant part in economic industrial progress. Australia is still a very young country industrially, and is groaning under many disabilities compared with competitors overseas, not the least of which is the quality of coal. Linked with the word "quality" should be that of "utility," for high-ash content prevents efficient utilization of the fuel.The marketing of good quality coal is a very important matter indeed, and if industry in Australia is to progress in the way that it should, this matter must receive keen attention.New South Wales, above all the other Australian States, has been blessed by nature with vast coal-fields, from which fuel is shipped to every State, and provides the base for power for most of our railroads and industries.Experts frequently refer to the fact that in some districts only partial extraction of thick seam coal is being made, without a care or thought for the future. Ranking next in importance to this is the fact that much of the coal is being carelessly marketed.Very few collieries in Australia are equipped with coal-washing plants for dealing more particularly with small coal grading which most industries require, and to which coal producers as a whole pay the least attention. In England each year nearly20,000,000 tons of coal is being water-washed before sale, and is marketed as a fuel of far greater utility once it has been freed from extraneous ash.Investigation proves that a great many pits in New South Wales are marketing coal (more particularly small coal) containing a considerable quantity of extraneous ash, due to the admixture...

Jan 1, 1926