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The method of investigation was to study the distribution of ore in great detail, to make a thorough structural study of the lode and the mine area, and then to compare the results of the two studies. Such a comparison usually reveals a very close relationship between geological structure and ore distribution, and can often lead to important conclusions which would not be reached in the ordinary working of a mine.The Triton mine lies 30 miles E.N.E. of Cue, or 380 miles N.W. of Kalgoorlie, in typical pre-Cambrian rocks, consisting of gTeenstone lavas and tuft's, interbedded with slates and some sediments, and intruded by granite and porphyry. Fig. 1 (at end of paper) is a longitudinal section of the mine and shows that the workings consist of the main North Emu and the smaller South Emu, separated by a distance of about 1 of a mile. Both orebodies occur on the same lode, which strikes north and south and dips practically vertically. On the same line, and of 1/2 a mile and a mile respectively to the north of the North Emu, are the small Rand and North Rand workings, where a big width of lode material has proved to be very low grade. In the North Emu the lode width averages 12 to 15 feet; it is seldom less than 5 feet and in places reaches 30 feet. In the South Emu the lode is wide, but only portion of it is payable.The lode is a mineralised bed occurring between massive lava flows on the east and a mixed series of tuft's and thin lava flows on the west. The lode material is hard, fine grained, and dark coloured, and generally has a faint banding which is believed to indicate a tuft'aceous origin of the original lode rock. Microscopic examination shows that the original lode rock has undergone considerable albitisation;' there has also been considerable formation of biotite which gives the lode material a characteristic sheen. The mineralisation consists of abundant fine pyrite, which is auriferous, and a lesser development of pyrrhotite which is, however, barren of gold.THE OREBODIES AND THEIR CHARACTERISTICSThe distribution of ore is best studied from gold contours, as these reveal features that cannot be detected in an ordinary assay section. Gold contours (see Fig. 3) are developed' by plotting the width and grade of all development and stoping assays throughout the mine on a longitudinal projection, representing each sample by a coloured dot according to a suitably chosen range of assay values, and then outlining areas of similarly coloured dots (see H. J. C. Conolly, Econ. Geol., April, 1936). Both width and grade must be taken into account and the simplest method of gold contouring is to use dwt.lft. values, but difficulties arise here with big widths of low grade and small widths of high grade ore. To choose an extreme case, 30 ft. of 2 dwts. and 2 ft. of 30 dwts. both equal 60 dwts.lft., and would therefore be given the same value in dwt.lft. contouring...

Jan 1, 1943

By Dunlop GA

Pilot Plant confirmatory testing of the treatment route developed in the Metallurgical Laboratory is an essential factor in the development of complex ore bodies. Objectives should be well defined to permit the efficient planning and cost effective operation of the pilot plant project. The primary objective for the pilot plant should be to confirm the viability of the developed flowsheet on a continuous basis, examining only major variables such as ore types, quantum changes in grind, comparison between bulk and sequential flotation circuits, use of flotation columns, evaluation of autogenous grinding and production of samples of concentrates for market evaluation. Secondary objectives may include the collection of engineering design data and the production of a comprehensive report to Bankable Document standards to provide technical support for capital financing. The complexity of the ore body and the scale of the final operating project together with the pilot plant objectives will determine the extent of the pilot plant operations. The level of expenditure associated with a pilot plant can vary, in total cost and as a percentage of the total development capital investment required to take the prospect from exploration to a producing mine. Factors contributing to expenditure are discussed. Associated with cost considerations is the level of confidence mining company investors can have that their capital investment will return dividends.

Jan 1, 1990

Particles of a complex nickel sulphide concentrate (containing pyrite, pyrrhotite, pentIandite, and violarite as the major mineralogical constituents) were entrained in a stream of hot gas the temperature of which was varied from 500 to -1000°C. Chemical analysis of the particulates collected from the furnace was used to detect the rapid change in sulphur content which accompanied the ignition temperature jump. X-ray diffraction analysis was used to characterize the oxidized material.These techniques showed that ignition was dependent on the mineralogical composition and occurred over the temperature range 500-900°C. Pyrite ignited first in the range 500-600°C; pyrrhotite was the least reactivemineral and required temperatures in excess of 800°C for ignition. The nickel minerals <pentIandite and violarite decomposed before ignition and ignited at temperatures intermediate to those required for the pyrite and pyrrhotite. The ignition temperature for the pyrite was found to be independent of particle size and concentration of oxygen in the atmosphere.Ignition temperatures determined by the simulated flash smelting method were compared with the results of differential thermal analysis (DTA) measurements performed on the same concentrate. Temperaturesdetermined in the DTA test as corresponding to the start of exothermic activity were shown to be at least 100°C below those determined by the simulation test.

Jan 1, 1978

The seams of black coal occurring in Victoria are so disturbed by faulting, wash-outs, thinning, etc., that it is necessary, for the prevention of costly errors in development, that close boring be undertaken so that the correct positions of the shafts, tunnels, main and auxiliary roadways can be set out in order that the area can be economically worked. The State Coal Mine has two boring plants continuously at work, which have given good service for the last twenty-five years.The information supplied herein is merely our experience in boring at the State Coal Mine over an extended period. The type of plant in use is that known as the Victoria Drilling Plant, equipped with an 11 h.p. portable oil engine, using power kerosene as fuel. It was purchased in 1914, complete with mechanism for cable drilling, capable of boring to a depth of 1500 ft. with a guarantee of 1000 ft., with Calyx cutters, boring rods and all necessary equipment for the sum of £1473. The chief mechanical features of the plant are as follows:-The derrick is in the shape of a tripod (see Fig. 1), two of the legs being of steel channel built together to form a frame which, when lowered on to two sets of road wheels, forms a carriage for the transport of a portion of the boring equipment. The third leg is made of oregon in the form of a double bow, with bolts and distance pieces between the wooden sides. The top of this is hinged on to the steel frame, and the bottom is fitted into a cast iron block, having two small wheels to facilitate erection. A rope attached to the cast iron block and to the winch easily...

Jan 1, 1936

By Johnson N. W

After an unsuccessful transfer from the laboratory to the pilot plant of galena flotation technology which used sodium metabisulphite and ethyl xanthate, laboratory flotation tests were conducted to identify any unusual variables which had a deleterious effect on the position of the lead rougher grade recovery curve for Hilton and Mount Isa silver-lead-zinc ores. Two variables (pulp temperature and contact time for ethyl xanthate and sodium metabisulphite) had important deleterious effects.The findings allowed a successful transfer of the laboratory process to a pilot plant scale process. The effect of temperature was important because the higher temperature (40°C) in the pilot plant pulp increased significantly the rate of reaction between ethyl xanthate and sodium metabisulphite. In the laboratory process at 20 to 25°C, the reaction rate was lower and did not interfere significantly with the process. The contact time for the two reagents was also important in the pilot plant scale process because of the higher reaction rate at 40°C.To employ ethyl xanthate in the pilot plant process, special precautions were required. Further, a collector (Aerofloat 241) from the dithiophosphate family was used successfully in the pilot plant process.

Jan 1, 1988

Flotation Research on Cassiterite of Tailings

Sep 13, 2010

Lead isotope measurements indicate that lead from the A.B.H. Consols mine and two transgressive veins in Browne's shaft is "Thackaringa" type and not "Broken Hill" type.

Jan 1, 1970

By Rose W. J

Geophysical prospecting was first recognized in Australia as an important aid to mining enterprises in 1927, when, on the suggestion of Sir Herbert Gepp, the "Imperial Geophysical Experimental Survey" was organized. The function of this survey was to carry out investigations on the applicability and efficacy of the most important geophysical methods under Australian conditions. The survey was formed under the joint auspices of the British Empire Marketing Board and Australian Commonwealth Government, and the investigations were carried out in Australia under the leadership of Mr. A. Broughton Edge, B.Sc., A.R.S.M., F.G.S., M.Inst.M.M., during the years 1928 and 1929. A description of the work performed, the apparatus used, the principles of the methods, and the results and conclusions of the survey are included in a report published by the Cambridge University Press in 1931.In 1932 Sir Herbert Gepp became interested in some gold mines in Eastern Victoria, in the Cassilis and Bethanga districts, and realizing that the lodes in these areas would be favorabIe for a geophysical examination, he arranged for a series of tests to be carried out. This work was performed by Mr. E. L. Blazey, B.E.E., a former member of the staff of the Imperial Geophysical Experimental, Survey, under the general direction of, and in consultation with, Mr. W. J. Rose, B.M.E.The work was commenced in October, 1932, at Cassilis, Vie., continued at Talgarno, Vie., .and concluded at...

Jan 1, 1933

Coal cleat and faulting influence failure, gas release, and choice of preferred mining directions, locations, and sequences. Unfortunately soil and younger rock cover restrict direct mapping of these structures ahead of mining operations. Aerial photographs of cover contain indirect indications of concealed structures in arrays of linear photostructures. These arrays are commonly too complex for interpretation by simple visual inspection.Analytical techniques applicable to complex arrays are illustrated for a covered part of the Galilee Coal Basin, Queensland. These techniques are: optical determination of sets in arrays of photostructures; correlation of these sets with sub-surface structures; filtering of m-rays for particular sets; detection of anomalies associated with concealed structures in the density distributions of particular sets; fitting filtered arrays to trajectories; correlation of trajectories with the regional directional variations of concealed structures; contouring of ratios of sets to discriminate anomalies associated with concealed fractures and variations in the total and bed thicknesses of cover; kinematic and dynamic inference on the basis of fracture-trace angular and spatial relationships.

Jan 1, 1979

By M Fallon

The full history of exploration successes, failures and related costs from initial greenfield exploration in 1987 to the current brownfield stages was analysed for the Plutonic Marymia Gold Belt of Western Australia. This belt, which had escaped the attention of turn-of-the-century prospectors and had not produced any gold until 1990, is an ideal area for a collectively exhaustive, progressive value and risk case study of expected return on gold exploration. The study analyses the progressive screening of over 200 greenfield and near mine prospects, through various stages of exploration to the establishment of 38 mining sites, ranging from a few large mines to small satellite operations. It provides empirical estimates of the historical Bayesian probability of projects advancing to successive stages of exploration, eg from reconnaissance, to systematic drill testing, resource delineation, feasibility and mine development, given a successful outcome in any exploration phase. The ratio between the estimated value of the gold discovered and the corresponding historical exploration expenditure in each year and cumulatively, ie the average cost of discovery per ounce of gold, are then computed as measures of historical return on the exploration investment in this belt. These, together with an estimate of the æresidualÆ gold endowment, ie of the number and size of possible as yet undiscovered deposits, generated through the use of rank statistics (ie ZipfÆs law), provide a basis for future strategic consideration in exploration targeting in this and similar geological terranes.

Jan 1, 2009

THE power requirements of the Mount Lyell Mining and Railway Company at Queenstown, Tasmania, have, since the inception of smelting operations in June) 1896, been derived continuously from the extensive forests in the watershed of the Queen River, adjacent to the works, the fuewoodbeing of good quality, mainly composed of myrtle or beech (Fagus Ounninghami), eucalypts, and manuka (Leptospermum ericoides). The country is very rugged and mountainous, indented by numerous ravines and gullies, and intersected by, many creeks, which are subject to periodical floods, under the influence of a heavy and persistent rainfall, which averages about 110 in per annum. The areas so far exploited aggregate a total of about42 square miles, and this denuded country gives promise of ultimately becoming very valuable pastoral ground for cattle-raising. The tonnage of wood yielded per acre varies from 40 to 100 tons on stack measurement of 80 cubic feet per ton, 60 tons per acre being considered a good average yield. The gross amount...

Jan 1, 1910

Development of Technology for Complex Uranium Ores Processing on the Flotation Process Basis

Sep 13, 2010

By C D. Strickland

Western Australia (WA) has been a significant world producer of titanium minerals (rutile, ilmenite and leucoxene) and zircon for over 55 years. In 2010, despite global difficulties, WA accounted for 12 per cent of world production for zircon, ten per cent for ilmenite, and eight per cent for rutile. With downstream processing, titanium minerals (ilmenite, rutile, leucoxene) and zircon exports for 2010 were valued at $511 M (Department of Mines and Petroleum, 2010).Production is dominated by two areas of the Perth Basin, namely the Eneabba and the Bunbury-Capel regions, which are located 240 km north and 200 km south of Perth respectively. Mineralisation is within Cenozoic beach or near shore dune deposits at three broad altitudes related to the present coastline, and two older higher sea-level still-stands. The titanium-zircon minerals presumably were derived from the underlying Mesozoic sediments of the Perth Basin. Contrary to expectations, age dating suggests that the ultimate source of most of this mineralisation was not the adjacent Yilgarn Craton. With the cooperation of industry, the Geological Survey of Western Australia has mapped all known significant titanium-zircon mineralisation within the Perth Basin. This mapping has identified ‘strategic mineral resource protection areas’ that should be set aside for future mining, ‘sterilised’ and ‘mined’ areas that generally do not restrict land use options, and ‘possible strategic resource areas’ which have exploration potential for hosting titanium-zircon mineral deposits.The Perth Basin is currently undergoing rapid residential and industrial development. By informing all stakeholders of the locations of potential mining areas, the titanium-zircon mapping has the ability to reduce future land use conflicts, and facilitate sequential land use planning. Appropriate planning measures are being implemented to ensure that the Western Australia’s titanium-zircon minerals industry remains strong and viable in the future.

Oct 5, 2011

A new test coke oven of 7 cu. ft. capacity is described. The oven was designed to simulate conditions in a central section of a battery oven and a special feature is the achievement of unidirectional heating from theflues on either side of the charge.The method of charging permits close control of charge conditions such as bulk density and moisture content.These conditions, as well as coking conditions (e.g. flue temperatures and coking time) must be varied to simulate conditions in different batteries. The effects of several variables on coke quality are discussed.Using test oven conditions corresponding to those of Newcastle steelworks batteries, good agreement was obtained between strength indices of test oven and battery cokes. For 17 tests, the average ASTM stability and hardness indices for the test oven coke were 38· 5 per cent and 69·7 per cent, while those for the battery coke were 37· 4 per cent and 67·6 per cent.Observed relationships between coke yield and productivity, and volatile matter and charge moisture are given.The use of a test oven to classify test coals into prime-, medium-, poor-, and non-coking coals is discussed.This may be achieved by observing the effects of the test coal in blends with other coals. The results of a series of blending tests are presented.The dangers of attempting to predict coke quality from a single coal property are pointed out, since this can be done only for very restricted ranges of coals.A diagram is given showing the established trends in the effects of blending various types of Australian coals on coke strength.

Jan 1, 1970

The history of mining is rightly proud of its achievements in improving productivity and cost improvements over the years. No matter what measure is used, tonnes per manhour, cost per tonne, etc vast improvements have been made over the last hundred years. In fact over the last ten years in Australian coal mines raw coal output per employee has increased by 60 per cent. When one examines why these improvements have taken place the principal reasons have been technological advancement in mining equipment, excavator and dump truck capacity increases, longwall and continuous miners continually improving in reliability and size. Of course all these improvements are correlated to an increase in capital cost. Even with the above-mentioned advances the pressure for increased performance is as strong as ever. The international mining and mineral-processing sector is currently operating in a recessive market with some traditional commodities, eg gold trading at 20 year lows. During recessive times senior management will demand greater returns on capital employed: the obvious choices being reducing costs or increasing throughput. In addition, head office environments will often place a capital freeze on operational management so the opportunity to take advantage of technological change is not available. The challenge is, therefore, to increase throughput and cut costs without the need for capital. The answer is to optimise the existing labour and plant. If done systematically a result in productivity improvement, in our experience, as high as 45 per cent can be achieved with the average across South East Asia and Australasia being 21 - 23 per cent. The intention of this paper is to present a systematic approach to labour and machine utilisation thereby gaining the greatest possible return on the existing capital base.

Jan 1, 1999

By S Hu, P Ni, H Xu, P Chen

Indosinian (T) orogeny amalgamated the Mongolia-Xingan fold zone, the North China continent, the Yangtzi platform and the SE China fold zone into a unified continent. The early to middle Yanshanian (J-K1) orogeny created a Cordilleran type active continental margin in East Asia, reactivated the consolidated East China continent, and generated a large amount of granitoids, calc-alkaline volcanics and W, Sn, Mo, Cu, Au, and U ore deposits. The late Yanshanian (K2) orogeny began a transition to the western Pacific type continental margin. A tensional environment led to the development of peralkaline magmatism and tne formation of continental basins with red beds. The Himalayan (Tr-Q) orogeny was characterised by a backarc spreading and rifting regime. The dominant magmatism was continental basaltic.

Jan 1, 1995

By D Craw

Formation of gold-bearing veins in Otago Schist was intimately linked to the structural evolution of the schist belt. The currently-exploited Macraes gold deposit formed in a regional scale shear zone during latemetamorphic uplift of the schist belt. Further exploration for this type of deposit will be facilitated by an increased understanding of the late-metamorphic structural evolution of the schist belt. To this end, a three-dimensional cross section through the Otago Schist has been drawn using structural data gathered at outcrops in a 20 - 40 km wide transect across central Otago. This is the first continuous detailed structural section to be drawn through the belt. The section spans an area from Textural Zone 1 metagreywacke of the Torlesse terrane in the northeast through TZ 4 schist in the central region and across the Caples-Torlesse boundary to Textural Zone 3 schist of the Caples terrane in the southwest. Two different late-metamorphic structural generations are identified in this section: the long-recognised Manorburn Generation, and a new æPoolburn GenerationÆ. The location of the Caples-Torlesse boundary has been refined on this transect by field mapping combined with whole rock geochemistry.

Jan 1, 2001

This article focuses on TurkeyÆs gold potential with respect to exploration, development and operation after 1985. Apart from TurkeyÆs geology, which offers a substantial number of volcanic-associated gold (Ag) and gold-copper (Au-Cu) projects, there are numerous other factors which make the country a favourable place for mining. Turkey has a mining history which goes back to pre-Roman times and an excellent mining code which ensures security for long-term production. In the country, the Government and local villagers are very positive and the country works extremely well logistically with excellent road and telecommunication links. The opportunities for new discoveries in Turkey are very high. Moreover, Turkey has its eyes turned west as it moves towards joining the European Community and it is no surprise that international companies believe it has got its timing as well as its partner relationship right. Newmont, Teck Cominco, BHP Billiton, Rio Tinto, Eldorado Gold, etc all have direct or indirect interests in Turkey, as do an increasing number of midtier and junior exploration companies. Turkish Koza Gold Mining is the first Au producing company of Turkey. The Eldorado Gold owned 245 t Kisladag Au deposit in Western Turkey is currently also producing Au. In the meantime Anatolia Minerals Development is advancing the 131 t resource at the C÷pler Au deposit in North Eastern Turkey. These are significant world-class deposits. Further encouragement for investment in the Au mining sector has been provided by the introduction of a new mining law in 1985. Foreign investments in the country were encouraged and have seen a rapid increase in the last two decades. Gross domestic product (GDP) growth is in excess of five per cent per annum, inflation is down from 70 per cent to single figures, the budget deficit has been cut by 40 per cent to 11 per cent and industrial output and productivity are increasing rapidly. Turkey is politically and economically stable, is a member of the European Customs Union, has a supportive mining legislation, is highly prospective and under-explored and hosts significant recent gold discoveries.

Jan 1, 2007

By Higgins RJ

Environmental investigations have been undertaken by Ok Tedi Mining Limited (OTML) since 1981 when the Ok Tedi Environmental Study was commenced. Environmental monit- oring and management programmes were implemented in 1983. The programmes included water quality monitoring, river flow and sediment monitoring, surveillance of aquatic biological communities and a health and nutrition survey of the local people. These original programmes have continued, and additional programmes of work have been developed and revised to reflect changing operations and the need to focus investigations on specific areas and issues of concern. In April 1990, following the establishment by the Government of Papua New Guinea (PNG) of environmental management criteria for the Fly River system, compliance monitoring programs were introduced. Details of the compliance and additional monitoring programmes undertaken by OTML throughout the Ok Tedi and Fly catchments, including programmes of investigation in the Fly River estuary, Gulf of Papua and Torres Strait, are presented.

Jan 1, 1991

Experimental results are presented for the anode overvoltage as a function of current density for different alumina concentrations in an alumina reduction cell. Voltage changes due to the electrolyte resistance and also the decomposition voltage, have been evaluated as a function of alumina concentration and anode current density. From these values of voltage, changes in the total cell voltage have been derived for changes in alumina concentration for different anode current densities. The results show that for each operating current density there exists a discrete alumina concentration that defines a minimum reduction cell voltage. Discussion is made about potential savings in power consumption when the alumina concentration is controlled.INTRODUCTIONThe standard procedure in the aluminium industry when analysing the cell-voltage required for the Hall-Heroult process for reduction of alumina, is to subdivide the total voltage into the following components (e.g. Pearson, 1955; Maritell, 1960).1. ohmic drop through busbars and joints2. ohmic drop through cathode lining3. ohmic drop through anode4. ohmic drop through electrolyte5. overvoltage at anode6. electrolytic decomposition voltage.(Overvoltages ,at the cathode are of negligible magnitude at all practical current densities.)It is understandable that the voltages assigned for each factor invariably differ for different workers...

Jan 1, 1965