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LAKE MARGARET is situate high up on the West Coast Range of Tasmania, and lies in a roughly triangular valley formed by the ridge of Mount Sedgwick on the south, the ridge formed by Mounts Geikie and Tyndal on the west, amid a ridge connecting Mounts Geikie and Sedgwick on the east. Any description of this hydroelectric installation, however brief, naturally divides itself into the following sections:1. STORAGE BASIN, &c. 2. DAM. 3. PIPE LINES. 4. POWER STATION. 5. TRANSMISSION LINES. 6. SUBSTATION 7. VARIOUS WORKS utilizing the power.The Storage Basin used is the natural lake itself, which has a maximum length of 110 chains, a maximum width of 40 chains, and a mean arelj. of 300 acres. The water-level of the lake, which has been maintained by a natural dam, is 2143 ft. above sea-level. The approximate catchment area at present appropriated is 7 sq. miles, and the rainfall, on the average, about 144 in. per annum. It is possible to increase this catchment area by suitable races, &c. Dam.-The dam constructed is of very small dimensions, and is not a storage dam in the usual sense of the term. The natural storage ot-the lake itself was used by means of a channel cut through the natural dam and thence to the mouth of the lake, the lake level being thus temporarily lowered while the outlet pipes, screens, &c., were placed in position, and the channel was then closed again with a concrete wall in which the pipes and screens are set. This channel was cut partly through rock and partly through sand and conglomerate boulders for a total...

Jan 1, 1915

Mineral deposits in New Zealand whose origin can be ascribed to primary magmatic segregations are associated with mafic-ultramafic complexes related to two orogenic episodes which took place during Palaeozoic and Mesozoic times. These mafic-ultramafic complexes are essentially of two types. One is ophiolitic and has podiform chromite mineralisation presumably formed below a spreading ridge. The other type occurs as intraplate layered intrusions in which Fe-Cu-Ni sulphides and Fe-Ti-V oxides have formed as a result of liquid immiscibility with the host magma, and have subsequently accumulated by gravity means. Generalised descriptions are given for some deposits in NW Nelson, Fiordland and Marlborough districts.

Jan 1, 1980

Total mechanisation in the Western district of New South Wales is quite a recent addition to productive methods in that State, for it was only in 1940 that the first colliery was equipped for this method of winning coal. Now almost all mines either are totally mechanised or are planning to get their coal by these means.This marked change in recent years is explained by the salient features of the industry's history. Collieries in New South Wales had generally been subjected to low selling prices forced on them by over-production and severe competition. Little money was available out of profits to purchase machinery, and returns on capital were so poor that inducement to invest money in the industry was nonexistent.The second world war brought price fixing at the already low prices. It was not until the post-war period that there has been any inducement to mechanise.Much credit for mechanisation can be given to the Joint Coal Board, a government body formed in 1948. Pursuing a broad plan for the rejuvenation of the industry, this Board, purchased large quantities of machinery for use in, mines under hire-purchase agreement. These agreements encouraged machine mining, and this fact, together with the ensuing production economies, has improved the financial position of the industry.The Board has also been instrumental in the granting of increases in the fixed price of coal, so that the industry has been given an even greater boost in the direction of mechanisation.

Jan 1, 1954

These may be of interest to members examining the collection of ores, etc., from Mount Lyell, which is a feature of the Victorian Gold Jubilee Exhibition, and may have some value as geological records. No. 7 and No 8 are analyses of samples of footwall rock from the Lyell Tharsis mine. No. 7 is hard, crystalline, fine-grained, and of homogenous structure. It has a dark-red colour, due to ferric oxide (Fig 1); and was taken from a place eight feet east of the ore body and about half way between the 50 feet and 100 feet levels. No. 8 is from the same excavation and from four feet east of the ore body it is softer than No. 7, being easily scratched with a knife-blade, of a deeper dark-red colour, and has a slaty cleavage.

Jan 1, 1902

As it is my opinion that deep alluvial mining in Victoria and in the Murray Flats in New South Wales is practically in its infancy, and considering that we, the old school of alluvial miners, who have thirty or forty years' experience to guide us, must in the natural order of things hand over the management of our mine, to the younger and less experienced' generation of miners, I thought that as our Association has been formed for the purpose of disseminating information and the exchange of ideas, a few notes on the practical working of alluvial mines might be of some service to aspirants for the position of mining manager.The greatest difficulty the alluvial miner has to contend against is the immense quantity of water contained in the drifts overlying the wash in the gutters or ancient river beds, and to cope with this water successfully and economically is the point to be aimed at by our mining managers; and if they thoroughly understand this part of their business in all its details, they will not only win kudos for themselves, but will be the means of saving large sums of money to the companies they represent, and, in many instances, will make a success of a venture which otherwise might be stopped for want of funds before it is properly proved. At the present time, although we have had over forty years' experience indraining the deep leads of the colony, I regret to say that a large amount of ignorance still prevails amongst both directors and managers.

Jan 1, 1901

By Woodcock J. T

A sulphide ion selective electrode (ISE) is suitable for control of sodium sulphide additions in flotation because it has a rapid response to changeS in S2- concentrations, can indicate -low concentrations at differentpH values, suffers from few interferences, and is robust enou'gh to use in a pulp. Three sulphidization techniques were studied using the lSE electrode for measurement and/or control of S2- levels. Metallurgy was assessedfrom concentrate grades and copper recovery.With slug additions of sodium sulphide, sulphidizing conditions were poorly defined and reproducibility tended to be poor. Although acceptable metallurgy could be achieved by multiple additions, sodium sulphide consumption was high.Controlled potential sulphidization readily gave good metallurgy. The optimum potential of the lSE for sulphidizing was about -500 mV versus SCE, but depended on sulphidization and flotation times; suitable times were3 and 5 min respectively for three to five stages. Application of this technique to previously untested ores gave good metallurgy in a first test in spite of variation by a factor of three in the sodium sulphide requirements ofthe ores.Simultaneous sulphidization and flotation was satisfactory when conducted at an lSE potential of -450 mV versus SCE. Mixed cha!copyrite-oxide copper ores responded satisfactorily.Besides optimizing sulphidization conditions it is also necessary to optimize xanthate additions (e.g. by measuring xanthate residuals).

Jan 1, 1978

W. Johnson (Consultant, Adelaide) : Is there any mineralogical evidence of temperature of formation of the amphiboles and other minerals present in the crocidolite veins and country rocks7.N. A. Trueman: I am not aware of any definite evidence of the temperature of formation of these minerals, but am of the opinion that high temperatures would not be present during crystallization.No evidence from the qUl'trtz, magnetite and hematite of formation temperatures is indicated and, as the carbonate is later than the other minerals it does not supply any data either.According to Miyashiro and other workers who have studied the composition and stability of the glaucophaneriebeckite series, minerals of riebeckite composition are stable over a wide range of P, T conditions. Recent work by W. G. Ernst, of the University of California, indicate that, in the presence of an Fe203/Fe304 buffer, riebeckite and crocidolite are more likely to form at low temperatures. The occurrence of riebeckite-crocidolite as authigenic minerals has been reported from several localities.Dr. MacLeod (Geol. Surv. of W. A.): Recent regional mapping by the Geological Survey of Western Australia has revealed a total thickness of at least 30,000 ft for the Proterozoic sediments in the Hamersley Basin. In this succession the asbestos-bearing beds of the Brockman Iron Formation at Wittenoom are overlain by some 20,000 ft of younger sediments and volcanics. With such a thickness of superincumbent material, it seems perfectly valid to involve

Jan 1, 1963

Some design and feasibility studies have been made into possible methods of economic recovery of sulphur from smelter gases emitted at Western Mining Corporation's Nickel smelter at KalgoorIie in Western Australia. The smelter discharges some 330 000 tonne/yr of sulphur dioxide in a stream of approximately 6 per cent by volume of S02.Three possible recovery methods have been considered:1. The manufacture of sulphuric acid using the contact process.2. The concentration of sulphur dioxide to a pure form using dimethyl aniline as an absorbing medium.3. The reduction to elemental sulphur using natural gas as the reducing agent.Design studies were carried out by final year chemical engineering undergraduate students at Royal Melbourne Institute of Technology (RMIT) in 1981 under the supervision of the author and other teaching staff of the chemical engineering department. These studies indicate that sulphuric acid manufacture is the economically preferred recovery route.Markets for sulphuric acid include several potential mineral processing applications and the established fertiliser industry.Sulphuric acid is currently manufactured in a number of plants located at coastal regions of Western Australia using imported sulphur. The sulphuric acid is then used for superphosphate or titanium dioxide pigment manufacture at adjacent plants.The possibility is considered of manufacturing superphosphate at Kalgoorlie from locally produced acid obtained from the smelter gases and from phosphate rock railed to the site from the coast. The advantages of such a scheme include improved scale and technology of operation compared with some existing coastal operations, use of a waste material to replace imported sulphur, and avoidance of costs and hazards associated with railing large quantities of sulphuric acid.

Jan 1, 1983

By Moskovits E. E

Spodumene was recovered from pegmatite by flotation in laboratory and pilot-plant tests using an anionic collector emulsion. A similar process applied to beryl pegmatite gave encouraging results.INTRODUCTIONOver the past two decades lithium and beryllium have aroused increasing interest in the metallurgical world. Both these light metals have potential uses in nuclear shielding and cooling and in lightweight alloys, and there is a growing demand for lithium chemicals for ceramics, air conditioning and lubricants. The use, technology and history of lithium has been surveyed by Schreck (1961).For many years, the only commercial production of lithium and beryllium was from pegmatite deposits amenable to hand cobbing. The most important minerals of these ores are spodumene and beryl, which are respectively lithium aluminium silicate and beryllium aluminium silicate. Norman and Gieseke (1940) investigated the treatment of lithium ores by froth flotation. The process of flotation of the pegmatite constituents away from the spodumene was applied commercially in 1951, and the operation has been described by Goter, Rainey and Hudspeth (1953). Subsequently, the flotation of the spodumene from the pegmatite was studied by Munson and Clark (1955) and Browning and McVay (1961), and this method has superceded the reverse flotation process commercially. Muskett, Tasker and Hobson (1962), in applying the method of Browning and McVay in pilot-scale tests, reported difficulty because of activation of quartz and felspar by iron salts introduced during milling of the ore.The flotation of beryl, reported by Ashton and Weir...

Jan 1, 1963

The projection of operating costs for mining, processing, and other site operating costs is an exercise which can be fraught with considerable peril. Not only are the physical characteristics of each mineral property unique, but a range of other factors will influence the consultant's approach to compiling cash flow estimates. This paper details some of the techniques used in estimating operating costs for use in order-of-magnitude cost studies and feasibility studies, and describes how to avoid common areas of difficulty. A series of examples relating to open pit gold mining and processing cost estimates illustrate these problems, and various corrective methods are described. The mining and treatment processes, and their associated cost elements, are followed in sequence of operation from on-going ore delineation through to disposal of the product. In addition the problem of assigning management, administration and overhead costs along with taxation allowances is addressed. Of critical importance is the application or possible misapplication of accrual procedures to the cost elements. In many cases such misapplication can introduce more pronounced errors with projects of short duration, such as the typical open pit/C.I.P. gold operation commenced in the last decade. The importance of providing verification of estimates depending upon the standard of the cost study is also investigated, and opinion is provided upon the minimum levels of verification necessary at various stages. Finally, the amalgamation of the various individual cost elements into a coherent whole is reviewed.

Jan 1, 1990

The sulphide ores of the principal lodes of the Boulder Mines are mainly composed of a schistose guess with a varying proportion of silica and lime, containing tellurides of gold, silver and mercury, associated with iron pyrites. It is a great difficultyto obtain pure and homogeneous samples of the tellurides for analysis, and from a number of tests made with excellent specimens it was found hardly possible to procure two to agree in analysis, the precious metals being found to be combinedwith tellurium in most varying proportions indeed, a close inspection of a partially crushed specimen will reveal, even to the naked eye, the various shades of colour characteristic...

Jan 1, 1901

The dynamic response of holdup in a continuous ball mill has a direct influence on the rate function of grinding kinetics and is useful for predicting the variation in the size distribution of the finished product with time.A model was proposed involving three interacting, completely mixed chambers and this was used to derive analytically the transfer function of the system, from which the unit impulse response and the unit step response of the holdup with feed rate were obtained.The theory was confirmed by comparing it with previously published experimental data for the residence time distribution of particles passing through a ball mill.

Jan 1, 1975

IN the irregularly shaped ore-bodies of the North Mount Lyell mine by overhead stoping, the method of filling the is a special feature.The situation of the mine two miles from the smelter and mill at an devation of 1000 ft. above the latter, precluded the economical use of granulated furnace or the mill tailings, even if these materials were as suitable for the purpose as the rock nowquarried at North Lyell methods at Mount Lyell have already been described in Proceedings of the Institute.*The breaking the ore in large dome-shaped stopes is still the rule, but the slope or "rill" is much flatter now than formerly. Owing the greater fluidity of the filling now in use, it is sometimes necessary to resort to square-sets, both at the ground floor and above, the roofs and walls are generally enough to permit stoping without timber, except for ground and occasional stacks on the rills.Sufficient area of ground floor has been beaten out to start overhead stoping, the dome back is partly formed, with its apex a rise which connects with the mullock-pass reticulation.(Sce 1 showing this reticulation in diagrammatic form.)

Jan 1, 1927

By Warren L. J, Horsley R. R, Meagher L

Mineral concentrators often use process water that is very saline and/or hard. In this paper the effect of increasing concentrations of sodium chloride and calcium chloride on the rheological properties of 70 wt% quartz suspensions (d5o - 10.6 ¦m) is reported. The apparent viscosity at 100 s t in 5 mol dm -3 sodium chloride solutions (approx. 300,000 ppm) was nearly 500 times the viscosity of water without salt or particles present. Part of the increase in viscosity is caused by aggregation (coagulation) of the suspension.

Jan 1, 1989

A quantitative chemical model of the rocks of the Broken Hill lode environment is presented to illustrate a stratiform orebody in a meaningful form to scientists interested in environmental control on the chemicalcomposition of sediments.Even though this study was restricted by the narrow range of rock analyses available it is obvious that significant chemical differences exist between the various rock units and also that some association of metallic sulphides with Ca, Mn, Fe, and P is indicated.Correlation of this evidence with that from other mining fields may point out more definite chemical relationships and elucidate the puzzle of the mode of formation of many stratiform orebodies.

Jan 1, 1968

By Taylor R. G

This paper reports a biogeochemical study of the Siberia lode of the Herberton tin field. Soil near the orebody contained high levels of Fe, Cu, Pb, Sn, As, Mld Mn. Polycarpaea spirostylis and Indigofera dominii were associated with these high levels but several other species apparently could not tolerate them. The potential of these species as indicator plants is discussed.

Jan 1, 1975

Were it simply a matter of extracting tin from the simple tin sulphide, the proposition would undoubtedly be simple enough. When, however, other valuable metallic sulphides are combined with the tin, and it is required to separate these intomarketable products, then the proposition becomes somewhat complex, and such is the case with the class of material of which I am about to write. The locality where it occurs is Howell, New South Wales, and chiefly at the Conrad Silver-Lead Mine. The tin sulphide occurs chemically alloyed with copper, iron and other metals associated with galena, pyrites, mispickel, blende and silver sulphide in varying proportions, and generally in a gangue of highly crystallised quartz.Several varieties of tin sulphides occur, and from the following analyses of three minerals, these being specimens specially selected free from foreign matters, it will be seen that the chemical composition is somewhat complex.

Jan 1, 1902

The variation of carbon monoxide and hydrogen utilization with the amount of the reductant in the blast furnace bosh gas was investigated for the No. 4 blast furnace at The Broken Hill Proprietary Co. Ltd.iron and steel works. Newcastle. The degree of CO utilization decreased with increasing CO in the bosh gas; the H., utilization increased with the H., content of the gas. Empirical relationships for CO and H., utilization are proposed.H2, is 3-6 times as effective a reductant as CO at present levels of CO (34-39 per cent) and H2 (6-10 per cent) in blast furnace bosh gas. H2, gas injection into the blast furnace is proposed as a means of lowering the coke consumption, and the economics of H2 injection are evaluated.

Jan 1, 1975

The State of New South Wales is highly favoured in having vast deposits of coal adjacent to and within easy reach of the coastal Ports. Not only is the quality of the fuel generally superior to any found in the other States, but it is greater in extent than in any other part of the Continent. For interesting and reliable details of the history of the discovery of coal, the geology of the coal bearing strata, analysis of the various coals and other valuable data, the readers are referred to the book recently issued by the New South Wales Government, entitled The Mineral Resources of New South Wales, by Edward F. Pittman, A.R.S.M., etc., by the direction of the Hon. T. L. Fegan, Minister for Mines. The mining community is indebted to the Minister for having had published the most valuable condensed record of the mineral resources of the State extant.For the purposes of this paper we will only give such a general description of the coal fields as will make it intelligible in connection with the subject of the coal mining in the State of New South Wales.

Jan 1, 1904

This paper deals chiefly with the preliminary examination, when a decision has to be made as to whether a prospect has a chance of developing into a mine or not. At this stage it is important to have a fairly clear conception of what is expected of the prospect, andjust what type of mine is sought. Much money can be wasted testing a prospect suitable for a prospector or small syndicate, but which never looked like becoming a mine of sufficient size to interest a company. When undertaking an inspection, therefore, it is necessary to have a broad outline, at least, of the policy of the principals for whom the report is intended.At this early stage it is frequently necessary to form an opinion of the prospects of a property on very meagre data. When new to this type of work one's first reaction is often th~t it is impossible to pass an opinion on the data available. It. is absolutely necessary,however, that an opinion of the possibilities and chances of favourable development be given; The report should strive to convey this information, making quite ::lear the risk involved, how complete are the data on which this opinion is based, and the possible magnitude of the prize. A Preliminary report has to state whether a property has sufficient prospects to warrant testing.The following procedure is suggested in order to make best use of the data and minimise hasty conclusions influenced by preconceived ideas-an ever-present danger.Examination.The first stage is the examination. This should aim at collecting all available significant data, but avoid clouding the issue with detail which, at this stage, will not affect the decision. The following points are considered to be the main ones for which to look:-Geological Environment.As good a working knowledge as possible'of the geology of the area should be obtained. Government Geological Survey reports and maps, if available, will be a big help. A detailed knowledge of the regional geology is not necessary a,t this stage, but a broad outline of the geological setting of the prospect under review, and also of any other important mines in the district, is often helpful in the final decision.The Nature of the Ore-Body.Any facts concerning the nature or occurrence of the lode should be noted as, coupled with experience of similar bodies, they affect the ultimate decision.Structural Control.This is probably the most important factor, in the light of present geological knowledge. Its chief importance is due to two facts:-(a) Structure plays one of the prime parts in ore deposition.(b) Geological knowledge, of structure is somewhat in advance of knowledge of other factors influencing ore deposition.

Jan 1, 1950