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THE Australian States and New Zealand have for many years provided instruction in mining, metallurgy, geology, and their allied subjects through their Universities and Schools of Mines. Though such education has been provided at considerable expenditure, there is no legal recognition whatever given to the holders of degrees, diplomas, or certificates granted by the authorities controlling these educational institutions. Certain of the, Australian States and New Zealand require, however, that mine managers and other officials employed by the mining industry shall 'hold' certificates granted by their respective Mines Departments.The position at present is that each educational institution is practically a law unto itself, and therefore in many ways there is a want of uniformity amongst institutions all aiming at the same result the training of mining men. The object of this paper is, in the first place, to point out certain aspects of this want of uniformity, and thereby how disabilities accrue. Some points in connection with the granting of State certificates will also be...

Jan 1, 1915

The usefulness of laboratory studies - petrology and mineragraphy in the search for, and investigation of, mineral deposits should not be exaggerated, but it should not be overlooked, because such studies will always contribute to an understanding of the geology of the deposits, and can on occasions provide invaluable information not otherwise available. A few examples furnished by the investigations of the Mineragraphic Section of the Commonwealth Scientific and Industrial Research Organisation will show this.Petrology.In the early stages of the investigation of the King Island scheelite deposit, during the war, when the nature of, the deposit was not understood, a series of samples embodying the exposed rock types was submitted to the Mineragrap;hic Section for petrologicalexamination by the Mineral Resources Survey. It was at once apparent to the petrologist that the King Island scheelite ore was a contact metamorphic deposit, in which a series of argillaceous shales, calcareous shales, impure limestones and limestones had beenintensely metamorphosed. The shales had been converted to finegrained biotite and actinolite hornfels, according to their lime content, and the impure limestones to fine-grained diopside hornfels, garnetdiopside hornfels and garnet hornfels (calc-flint), the garnet being the lime variety grossularite. The limestones, however, after being first converted to marbles, had suffered intense pyrometasomatism, involving substitution of immense quantities ,of silica and' iron for lime and carbonate, and had been converted largely to a coarsegrained garnet rock, in which the garnet was the lime-iron variety, andradite. The silica and iron were derived from the mineralising solutions of the adja,cent ,granite. intrusion, responsible for the contact metamorphism, and were accompanied by tungsten and some molybdenum. The tungsten in the presence of so much mobile lime, was precipitated as schecelite, much of it finegrained and enclosed in or intergrown, with the andradite garnet or the quartz interstitial to the garnet.It was apparent that the King Island scheelite deposit, was a perfect example of selective pyrometallomatic replacement in a bedded contact metamorphic deposit. The bedded nature of the original rocks was preserved, and the scheelite was practically limited to the original limestone beds, 'Which had been so much more susceptible to replacement after recrystallization, than the other sediments. The further geological study of the deposit then resolved itself into the task of mapping the folding and faulting of the deposit, with bore cores to provide the stratigraphic sequence, and establish the number of scheelite-bearing beds.A second example is provided by a petrological investigation of the mineral composition and genesis of the talc deposits of the Gumeracha district of South Austral.ia, which was undertaken at the request of the South Australian ,Mines Department, in conjunctionwith mapping of these deposits. The field geologist mapping the deposits was experiencing some difficulty in interpreting the structure...

Jan 1, 1950

Radioisotope x-ray and neutron techniques of analysis can be used for the determination of a wide range of elements in minerals. The most important applications of these techniques to the mineral industry are for onstream analysis of slurries and solids, and for geological assay.The radioisotope x-ray techniques are the more developed ones and two installations for on-stream analysis are in routine use in mineral processing plants in Australia. Neutron techniques are being developed, and should prove valuable for geological assay of large numbers of mineral samples, for borehole logging, and for specific on-stream analysis when the cost of the equipment is warranted.

Jan 1, 1970

Mount Isa Mines Limited first installed electronic data processing equipment in 1959. The decision to replace this equipment with a computer was motivated by the need for greater processing power and the availability of new and less expensive computers. Consideration of hardware software and delivery features of available equipment, resulted in the selectIon of an ICT 1900 series computer which was installed in March 1966. Special air-conditioning and power stabilization equipment was also required.Systems design and programming was carried out by personnel recruited from within the Company and trained by the computer manufacturer. Early work was hindered by the problems of remote location.Initial applications were basically accounting functions whIch were taken over from the EDP installation. Subsequently computer applIcatIOns of a more complex technical nature have been undertaken. Future work will include both "scientific" and data processing applications.

Jan 1, 1968

The commonly used Stopes-Heerlen coal petrographic classification and nomenclature has over the years been subject to variable interpretations. This paper discusses the problem with specific reference to the inertinite maceral group. The effect of various interpretations of the Stopes-Heerlen system on maceral analysis is discussed and illustrated by means of comparative analyses conducted by a number of laboratories in Australia.An attempt is made to define the reflectance thresholds used by the authors to subdivide the inertinite group; the genetic and technological significance of these thresholds are compared.The difficulties of distinguishing structured and nonstructured macerals of the inertinite group are discussed in terms of possible improvements to the present StopesHeerlen system by extending the classification to include transitional maceral types.

Jan 1, 1970

Process Options for Difficult Arid-Region Nickel Laterites In the absence of the discovery of significant nickel sulfide deposits, the future of Australia's nickel industry will increasingly depend on cost effect processes for low-grade nickel laterites. The problems encountered with the West Australian HPAL plants, resulting in three of the four plants being shut down, have caused the industry to revisit atmospheric leaching options, particularly heap leaching. West Australian laterites are characteristically very varied in grade, chemical composition and mineralogy with the result that, thus far, one process does not fit all laterites. In this paper the leaching of an especially refractory ore is compared using column leaching of whole ore and atmospheric leaching and HPAL processing of ground ore. The key characteristic is the resistance of the goethite phase to acid attack with low-to-moderate temperature leaching conditions. The refractory characteristic is attributed to the stabilising influence of chromium and aluminium and possibly manganese substitution in the goethite crystal structure and goethite morphology. A significant three-fold increase in both nickel and cobalt extractions under atmospheric leaching conditions was achieved by the relatively simple modification of bubbling sulfur dioxide into the reaction vessel to create a reducing environment. Recoveries increased from <30 per cent to 90 per cent nickel and 86 per cent cobalt after 10 hours of leaching at 95¦C. An even greater improvement was achieved under ambient conditions by heating the ore to temperatures above 250¦C for 30 minutes. Subsequent leaching at ambient temperature gave an eight-fold increase in both nickel and cobalt recoveries after 14 days bottle rolling. Both methods could be optimised and implemented in such a way as to increase laterite reserves in conjunction with a heap leach operation but may be better suited to vat or closed tank processing.

Sep 13, 2010

By P G. Self, M D. Raven, R A. Eggleton

Investigation of an abandoned quarry near Rowland Flat in South Australia identified asbestiform antigorite as the fibrous serpentine mineral mined during the 1940s to 1978 for filler applications, not amphibole asbestos or chrysotile as reported in earlier investigations. Scanning and transmission electron microscopy (SEM and TEM) and selected area electron diffraction (SAED) of individual fibres were used to confirm the identification. Chrysotile is widely regarded as the only asbestos mineral in the serpentine group. Further work was done therefore, on the geology and mineralogy of the occurrence, and the health implications were reviewed. A zone of antigorite alteration, with associated talc, is traceable for 750 m along strike of recrystallised dolomitic siltstone within Woolshed Flat Shale of Neoproterozoic age. The antigorite formed, in part, by replacement of prismatic crystals of probable tremolitic amphibole. The deposit is proximal to the Williamstown Fault and the serpentine-talc alteration is possibly due to fluids expelled along the fault during late-stage deformation in the Early Palaeozoic Delamerian Orogeny. The antigorite comprises white to pale green bundles of lath-shaped fibres that occur either as randomly- arranged equant patches after amphibole or as cross-fibre veins, both intimately mixed with calcite. Highly fibrous product was mined from the weathered zone where calcite was leached during weathering. Gentle grinding releases fibres with a high aspect ratio (>10:1) that show a wide range of fibre thickness, including a significant proportion of fibres <0.25 ¦m width. Toxicological studies on fibrous antigorite from Poland and Italy indicate that the carcinogenic potential of this form of serpentine is similar to amphibole asbestos. X-ray diffraction (XRD) and fourier-transform infrared (FTIR) techniques readily distinguish antigorite from chrysotile. Determination of asbestiform habit and confirmation of antigorite mineralogy is most reliably done using electron microscopy, preferably with SAED capability.

Jan 1, 2008

This paper addresses, in particular, the influence of winding depth on the selection of head ropes for Koepe winders. Because this is just one aspect of winder design that affects the operational safety of the winding system, the paper starts by considering all the issues governing the life and safety of the winding ropes. Regulations from a variety of countries are reviewed and comparisons of the legislated rope factors of safety and their variation with winding depth are made. This is followed by a discussion of the typical observed mode of in-service deterioration of Koepe head ropes. This mode of deterioration is due to fatigue and is influenced by the load range occurring in the ropes. Parameters contributing to load range are discussed and the influence of winding depth is highlighted. Lessons learned from early experience with very deep Koepe winders in South Africa are recalled. Predictions of load range as a function of depth are made, from which general rope life predictions are made for ropes selected by conventional national factor of safety requirements. This is illustrated in graphs comparing rope life as a function of depth. Typically a reducing life with depth is predicted. A rope selection strategy is advocated, which is based on achieving a constant rope life irrespective of the depth of wind. A new factor of safety (or rope design factor) equation is prepared that has the trend of increasing with depth. This proposed equation is compared with other published proposals that promote an increasing rope factor of safety with depth. It is shown that smoother winder drive controls enhance winding rope life and this improvement is quantified. The paper concludes by pointing out the consistency in predicted and observed life of winding ropes selected in accordance with legislated factor of safety approaches. It recommends the adoption of a new rope design factor equation for rope selection, to be used in conjunction with appropriate codes of practice for winding rope condition assessment and for the design, installation, operation, maintenance and testing of Koepe winders. The new rope design factor equation approaches a limiting economic depth of wind at shallower depths than the existing Koepe factor of safety approaches. However these older approaches æbuild-inÆ a reducing rope life with depth. The new rope design factor is therefore a more consistent way to select Koepe ropes and to evaluate economic trade-offs between Koepe and conventional double-drum or Blair winding systems.

Jan 1, 2005

The Beginnings of Mineral Processing Research in Canada - A Short Account

Sep 13, 2010

Over half of the molten aluminium produced at the 52,000 tons/ year eapacity plant operated by Comalco Aluminium (Bell Bay) Limited in Tasmania is cast into saleable produets by the direct chill process. Considering the importance of direct chill casting to the aluminium industry it is surprising that so little published literature on the subject is available, although Easton (1947), Smart (1954), and Uppert (1940, 1944, 1945) have contributed much toward lifting the veil of secrecy surrounding the process.The direct chill, or D.C. process as it is commonly called when related to aluminium, consists basically of feeding molten aluminium or its alloys into; water-cooled mould from the bottom of which solid aluminium is continuously extracted. Although the casting procedure is continuous in principle, the equipment is normally operated in an intermittent manner. Castings up to 20 ft long are formed during a cycle. At the end of the cycle casting is stopped and the pit into which thc castings are dropped is cleared before a new cycle commences. Depending on the size of the casting in relation to the cross sectional area of the pit and the support mechanism (commonly a hydraulic ram), 'drops' of up to 15 tons are not uncommon. This method of D.C. casting IS termed vertical D.C. casting and is the one most commonly employed in the aluminium industry.Horizontal casting has come more to the fore in recent years with the casting being extracted from the mould in the horizontal plane and is a truly continuous casting method since flying saws can be simply used to cut the continuously cast shape into required lengths as it emerges from the mould...

Jan 1, 1967

By Schlanger H. P

A theoretical model for gas outbursts in underground coal mines is as follows. An outburst is the structural failure ofcoal due to excess stress resulting from body forces caused by gas pressure gradients. These body forces influence the stability of a mine face in the same manner that gravitational body forces affect the stability of the roof of a mine. The magnitude ofthese body forces can be appreciated when it is realized that for an average density coal, the gravitational body force is equal in magnitude to the force from a gas flow with a pressure gradient of 14 kPa m-I. Gas pressure gradients and the resultant stresses within a seam can be calculated with numerical methods. Thus, providing the necessary parameters can be measured or estimated, in principle the theory can be applied to compare the outburst risk of various mining arrangements.

Jan 1, 1985

By G McMillan, P Mulvey

"Geochemical characterisation is done based upon the geology and metallurgical batch testing prior to commencement of the operation of the plant.  Tailings repository design is based upon geochemical assessment of the waste material, as well as the geomechanical issues associated with storing the waste. The resultant conceptual and detailed design is incorporated into the environmental impact statement (EIS), upon which mine approval is based. The entire environmental monitoring and harm mitigation program, which is usually a condition of the Mine Lease approval, is based upon the applicability of the original characterisation.Tacit to this process is that there is no change in the geochemistry of the tailings, i.e. no change in the implications for acid & metalliferous or saline/neutral mine drainage (AMD/SNMD) generation. But any changes in milling and processing can have a substantive impact on the geochemical behaviour of the tailings metallurgy, and potentially render an operation non-compliant within the conditions of the mine license.Environmental and statutory approval implications for continuous improvements of metallurgy need to be understood because unintended consequences could cost more than the benefits of the improvement, and in some cases cost more than all the profit made from the mine.  Examples uncovered during audit and consultant practice will be presented together with a process to ensure implications for adverse environmental harm and license conditions are fully considered.*This paper is only available for individual download. It is not included in the conference proceedings*CITATION:Mulvey, P, 2013. Continuous improvement - how changes in metallurgy can have a substantive impact on environmental impact and closure - lessons learnt from environmental auditing, presented to MetPlant 2013 Conference (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

Interest in industrial minerals in recent years has increased to such an extent that it has taken them into the mainstream of the Australian mineral industry. Notwithstanding that time series data on the values of production, exports, and imports show that industrial minerals are overshadowed by metals and energy minerals, their contribution to the national economy is important and more significant than would seem to be indicated by the statistics. Whereas the ex mine value of metals generally includes some processing (at least to a concentrate stage), most industrial minerals are valued at little more than their extraction cost, in addition to which such costs are generally low because most industrial minerals are exploited in low-cost surface operations. Consequently, values of mine production of metals and industrial minerals are not strictly comparable in that values of mine production of metals tend to be overstated Short term growth of the industrial minerals sector is assured because of several new projects already commissioned but not yet reflected in the statistics. Longer term growth is also assured, based on various other major projects that are likely to come on stream in the early to mid 1990s.

Jan 1, 1989

The point of the anode effect on carbon anodes of dcfincd surface area. during electrolytic decomposition of alumina dissolved in molten fluorides. has been determined from current-voltage curves. The reproducibility and accuracy was found to be better for cell voltage than anode current density. Results have been obtained for the effect of alumina concentration temperature and carbon type. The point of the anode effect was strongly dependent on both the alumina concentration and the carbon type. For high alumina concentrations it has been found that the anode effect approaches reversibility. From these results it is concluded that co-evolution of CO, and CF. occurs prior to the onset of the anode effect. The anode effect results when the CF, content becomes sufficiently high for the melt not to wet the electrode surface and is maintained because of the slow desorption of CF, and the high electrode potential that results.

Jan 1, 1967

A short account is given of the theory and practice of determining the true U3O8 content of ore samples by the determination of the beta and gamma activities separately, using the method of Eichholz and his associates.It is shown that, despite the variation of sample activity without change in U3O8 content, the true U3O8 value can still be found.Thorium can be determined simultaneously if this element is also present.

Jan 1, 1957

In the course of work being carried out in the Lubricants and Bearings Section of the Council lor Scientific and Industrial Research on the production of copper4ead 'bearings for 'use in aircraft, it has been found necessary to develop special metallographic methods. For proper control of the production of steel-backed copper-lead bearings it is necessary to adhere to rigidly controlled conditions, and it is essential that a method of examination be adopted which will readily detect actual defects or any variations in quality. Some defects can be observed with the naked eye, whilst others are detected by radiographic examination. This latter method is invaluable as a rapid, reliable test in the production of aircraft bearings, but it is necessary to observe the structure of the alloys under the microscope, both to be able to interpret the radiograph correctly and to determine what has occurred to the metal during and after solidification. The use of a sound metallographic technique is'particularly important in developmental work and research connected with these bearings.Polishing TechniqueCopper and lead are practically immiscible in the solid state, but whilst they are miscible only in certain limited proportions in the liquid state; consequently "alloys" of copper and lead consist of a mixture of the constituent metals. The metallographic difficulties are obvious. Copper is a relatively tough metal, although it readily scratches, whilst lead is extremely soft and easily deformed. It wouId be expected if any normal polishing technique were applied that the lead would be readily torn out of the surface being prepared, and, in addition, that the lead would tarnish very easily.Grange(2) has described a method by which these difficulties can be overcome. The method involves an etch-polish procedure using "chrome regia" as an etchant for the copper. The chrome regia was a solution of chromium trioxide and hydrochloric acid in water. This type of etchant has been adopted, but it was found necessary to make certain changes.The method now adopted in this laboratory is as follows: The specimen (which is usually mounted in bakelite) is wet ground in a series of successively finer Hydro-Durexsil emery papers down to 60.0· grit paper.The specimen is then etched in the chrome regis, etchant (the composition of this etchant will pe discussed later) for approximately five seconds.Most efficient etching is obtained by swabbing the surface of the specimen...

Jan 1, 1944

Delhi Australian Petroleum Ltd., acting as operator for the joint interests of Delhi and Santos Ltd., has been engaged in petroleum exploration in the western Great Artesian Basin since 1958.Extensive airborne magnetometer, gravity meter, reflection and refraction seisomograph, and surface geological surveys have been carried out. Results of the surveys have considerably altered the concepts of the geology of the area.Seven exploratory wells have been drilled in the area. Results of the drilling have established the presence in the subsurface of previously unknown Paleozoic sediments which are capable of generating hydrocarbons.Production of oil or gas has not been achieved, but each phase of the exploration programme has resulted in progressively establishing the basic conditions necessary for the discovery of commercially profitable accumulations.INTRODUCTIONDelhi Australian Petroleum Ltd. commenced operations in Australia in 1958. They have subsequently been engaged in systematic exploration for oil and gas, acting as operator for their partner, Santos Limited. The methods and techniques employed are those used throughout the petroleum industry. The results of the exploration programme contribute to a better understanding of the basic geology, and concomitantly a firmer analysis of the petroleum producing potential, of the western Great Artesian Basin.Each phase has progressively enhanced the gross geological interpretation of the area with regard to favourable conditions for the generation and accumulation of hydrocarbons, but the stage has not been reached where productive potential is definitely established.Exploration status in 1958Basin configurationIn 1958 knowledge of the pre-Jurassic stratigraphy of the geographically defined western Great Artesian Basin...

Jan 1, 1964

By K M. Brodie, D I. K McLeod, J Ruddock

Environmental incidents involving mine tailings and waste rock inevitably become highly publicised and serve to damage the credibility of the entire industry. The recent serious incident involving a spill from a Romanian mine, was blamed for triggering æone of the worst environmental catastrophes in Eastern EuropeÆ. It is important to clearly demonstrate to the general public that these incidents are not representative of the industry as a whole. Where such incidents have occurred, the causes are generally related to poor design and/or construction, inadequate supervision and/or monitoring and maintenance, lack of independent expertise, inadequate risk identification and treatment and no provision to ensure that rehabilitation and long term management of the site occurs. Many people are unaware that these issues have been considered and provided for at the Martha Mine. Despite the fact that the first tailings storage facility has performed very well over fifteen years of operation, the long term safety and security of the tailings storage facilities continues to be questioned and debated by the public. The best way to address this is to provide quality information to enable a better understanding amongst the general public.

Jan 1, 2002

By Delahant A. B, Dworski M

From the Saranac Laboratory for the Study of Tuberculosis of the Edward L., Trudeau Foundation, Saranac Lake, New York:We are assembled to honor the memory of our friend and colleague, Donald Cummings, one of the founders and a past president of the American Industrial Hygiene Association. I deem it an Unusual privilege to have been asked to give this first memorial lecture and hope that what shall have to say may be worthy of the occasion. It is fitting that we should discuss here the subject of Silicosis to which he devoted such a large part of his life and it is doubly fitting, I think, that I should report to you an extended series of investigations carried on by his associates at the Saranac Laboratory.The subject of silicosis may seem hackneyed to this audience which is so familiar with the tried and accepted methods of prevention and control.But in spite of our efforts, the condition is still with us and unfortunately is still being produced in many places. In industries that now maintain good control of dust, fresh cases are appearing on annual re-examination, whose major exposure date back to the days before the hazard was recognized.A few new employees, with apparently ineffective upper respiratory protection against inhaled dust, develop silicosis precociously in environments that are comparatively harmless to their fellows. In plants that have relaxed their vigilance under the urgency of war production schedules, conditions again prevail that will produce, disease in the future.Silicosis acquired new interest with the announcement by Denny, Robson and Irwin(1) in 1937 that it could be prevented by the inhalation of powdered metallic aluminium. It so happened that without knowledge of their work, we at the Saranac Laboratory had for some months been conducting similar experiments with one of the hydroxides of aluminium.Quite independently we discovered that hydrated alumina would also protect animals against quartz. Our approach to the problem had been empirical; we were trying to neutralize quartz particles by coating their surfaces with an insoluble material following the lead of Kettle who in 1932 had shown that this could be accomplished with iron. He neglected to describe his method and the chemist who prepared his coated...

Jan 1, 1945

The modern Golden Cross mine entered the production phase in January 1992. The project is designed to produce over 100 000 oz/yr of gold and over 300 000 oz/yr of silver during a mine life of eight years. An open pit and an underground mine are operated producing around 850 000 t/yr of ore, to feed a conventional carbon-in-leach processing plant. Golden Cross is owned in joint venture by Coeur Gold New Zealand Limited (80%) and Viking Mining Company Limited (20 %).   Since the start of production several major aspects of the design have altered. The underground mine began as a mechanised cut and fill operation. The cut and fill stoping progresses in 3.3 m flatback lifts with maximum stoping width of 6 m. Where the ore zone is wider than 6 m a post pillar cut and fill method is used. In 1993 a new bench mining plan was introduced between the 270 and 260 levels. Flatbacking continued in the footwall drives in anticipation of variability of the ore width and orientation. The development of levels below the main service 200 level has indicated a possibility of bulk mining the ore block rather than flatbacks. This could lower mining costs but also introduce higher dilution rates. Development is in the advanced stages for trialing this method.

Jan 1, 1994