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By Cordner G. D

Titanium is not yet being produced on a commercial scale despite the facts that it has some impressive properties, and that it occurs very abundantly in easily-mined, highgrade oxide ores. One important reason for this is that the excellent mechanical properties of the metal were not widely recognised and appreciated until about twenty years ago.Another factor which has tended to retard progress in titanium metallurgy has been the realization that the oxide minerals of titanium are very stable; in other words, considerable energy has to be expended to reduce the oxide to metal. Table 1 presents the minimum energies which would have to be expended to produce one ton of each of the metals, aluminium, magnesium, titanium and iron from their respective oxides under theoretically ideal conditions at normal temperature and pressure. At higher temperatures, the minimum energy requirements are different, but the values for the various metals still fall in the same order as indicated in Table 1.In actual fact, the energy consumption in the case of any particular metal is higher than the ideal value by an amount which can be determined only by' the results of plant practice. The only general conclusion that can be drawn from the data in Table 1 is that it might eventually prove...

Jan 1, 1950

It is easy to demonstrate the importance of aggregates in any conversation about infrastructure and other engineering artefacts. Peoples around the world have made use of stone to enrich and enhance their lives since the earliest days of civilisation. In New Zealand, Maori used hard durable rocks for weapons, tools, and basic structures. European settlement accelerated the use of quarried materials and formed the basis for development of our society as we see it today. Logic might suggest that the quarrying sector would be recognised positively for, and encouraged to continue to contribute to, this underpinning of the way we are. The reality is æNot In Most Back YardsÆ. Why? The rock is where it's always been (often overlooked) and our æsocialÆ environment is today's hard place. For a resource-based business in New Zealand, that environment is principally the Resource Management Act, with the widespread power it has distributed to anyone prepared to invest their time. This coupled with a lack of leadership and direction in the implementation of the Act has created a climate that stifles development and diverts energy and resources to æplaying the gameÆ rather than ælifting the gameÆ. Perhaps the real costs of this are not yet widely recognised. The paper will draw mainly on the experience of endeavouring to consent a ægreenfieldÆ quarry in the Waikato region. This is supported by commentary based on nearly 10 years of ælivingÆ with the RMA at sites across much of New Zealand. RMA Scorecard Summary: Effects based? Rarely. Level playing field? No. Maori Consultation? Could do better. Efficient use of resources? No. Timely? No. Is it working for other sectors? Certainly not the quarrying industry's customers and end users.

Jan 1, 2000

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

Mt Waruwari, host to the Porgera underground gold mine in the Highlands of Papua New Guinea (PNG), is a prominent ridge of sediments and dioritic intrusives rising approximately 600m above the surrounding valley floor. Consequently, mining occurs in a low stress environment where structural and material considerations are foremost in the design of ground support and reinforcement. Three major rock types are encountered in the underground mine. These are locally referred to as "black sediments" (slightly indurated mudstones and clayey siltstones), "altered sediments" (derived from black sediments by thermal metamorphism), and "intrusives" of dioritic composition. The rocks are moderately to highly fractured, the black sediments being generally weak and occasionally sheared while the altered sediments and intrusives are quite strong but often brittle. Mining takes place from a series of stopes extracted by either slot and mass blast or a modified vertical crater retreat method (VCR), which are backfilled with a cemented rock fill. Ground support and reinforcement has been relatively conserv- ative to date and generally relies on pattern reinforcement of all development with cement grouted "rebar" bolts and mesh, extending to pattern cable bolting with occasional mesh in stope backs. In addition there has been considerable reinforcement of stope hangingwalls in some cases. A programme of broad scale structural mapping, monitoring with extensometers, material property testing, and stress analysis has been devised to allow optimum design of ground support and reinforcement in the future. Considerable work remains to ,omplete this task.

Jan 1, 1991

The structure of the Bulli coal seam at Appin Colliery was detailed by the seismic reflection method. This unusual application of the seismic method was possible because there is a reflector near the seam as was revealed during exploration for petroleum in an area north-west of Appin. The reflector, which was at a depth of 1,500 ft, was shallow by normal reflection survey standards. Measurement of the seismic velocity at two ventilation shafts showed that the reflector was probably the Bulli coal seam. Accurate depth control was established from previous drilling results.INTRODUCTIONAppin Colliery, situated on the Southern Coalfield of N.S.W. (Fig. 1), is being developed to supply coking coal to the Port Kembla steelworks of Australian Iron and Steel Pty. Ltd. The colliery is mechanized and a detailed knowledge of structure, particularly faulting, is important in planning the workings.The Bulli seam, which is approximately 9 ft thick, and between 1,500 ft and 1,800 ft below the surface, is worked in the colliery. It is the uppermost member of the Permian Coal Measures and is overlain by Triassic rocks, which consist of thick sandstone beds containing beds of coloured shales, and which are subdivided into the Narrabeen Group, the Hawkesbury Sandstone, and the Wianamatta Group.In the early stages of development of the colliery, surface geological mapping and diamond drilling provided information on structure. Generalized results of the mapping are shown on Fig. 2. Drilling indicated that the physical and chemical properties of the Bulli seam are relatively constant, and that the seam is nearly horizontal, the average dipbeing about 1 in 25 to the west.

Jan 1, 1965

Large scale fluid extraction from the Latrobe Group in the Gippsland Basin is occurring as a result of offshore petroleum production and coal mine dewatering in the Latrobe Valley. Groundwater extraction in the Latrobe Valley exceeds recharge and is causing an expanding area of declining hydraulic head in the Latrobe Group, and regional land subsidence which is well documented. Recently the government water sector completed the installation of a network of Latrobe Group monitoring bores in the remainder of the onshore part of the Gippsland Basin. The bores situated along the coastal area show a steady decline in hydraulic head of about 1 m/year which can be attributed mainly to petroleum production.

Jan 1, 1992

By Clarke P. E

At the end of the recent war, reports became available from Europe of the use of tungsten-carbide inserts in percussion rockdrill bits. These bits were used with small size rockdrills, so that the only advantage gained from the use of the harder, abrasion resistant, tungsten-carbide appears to have been the greater life of the bit. Larger machines, such as used in Australia in conventional practice, had to be discarded to protect the relatively brittle tungstencarbide inserts and the vulnerable bonding with the bit body.As it had been found in machine shop practice that some grades of tungsten-carbide had been produced with considerably improved toughness, it was decided by Gold Mines of Australia Ltd. that drilling practice with tungstencarbide bits warranted detailed examination under Australian conditions, and that drilling tests should be undertaken at Morning Star (G.M.A.) Mines N.L., for which it acts as General Manager and Consultant.These investigations progressed through three stages:1. Preliminary Investigations and Tests.When the investigations were initiated no commercial bits were available in Australia, and manufacture was commenced with improvised equipment from virtual scratch. These early tests indicated that the use of 3 in. bore rockdrills in conjunction with tungsten-carbide insert bits was a 'possibility, and that it was unlikely that a small bore...

Jan 1, 1950

The Tasman Orogenic Zone is regarded as a single metallogenic province (the Tasman Province) with four SUb-provinces corresponding with its major tectonic components: the Lachlan, New England, Hodgkinson.and North Queensland orogenic provinces. Within the Tasman Province there are four main ore-rock associations.These are1. manganese and iron with sedimentary and basic volcanic rocks,2. zinc-lead-copper and copper with intermediate-acid volcanic sequences,3. minor chromium, platinum, and osmiridium with ultramafic complexes, and4. tin, wolfram, gold, and copper with syn- and posttectonic granitic intrusions.Whereas the ores of ultramafic and volcanic associations form geographically-restricted metallogenic districts, the ubiquitous granitic ores may be subdivided into twenty-one districts that cover almost the entireOrogenic Zone. The Tasman Province is notably lacking in uranium ores and Mississippi Valley-type deposits.There is a distinct tendency for ores of each association to be progressively younger to the east and north, thus paralleling the progressive growth and stabilization of the Zone. Similar ore-rock associations are present in repeated phases of mineralization from the Cambrian to the Permian-Triassic, reflecting the essential homogeneity of the Tasman Province, and the similarity of the successive tectonic cycles.

Jan 1, 1972

The Porgera Joint Venture commenced production during September 1990. A small tonnage underground mine extracts high grade gold ore using small scale stopes. Conventional drill and blast methods are used for development and production mining. Ground support is effected with Splitset anchors, grouted rebar bolts and grouted cable bolts. Splitsets and grouted rebar can be installed by mechanised means. Vertical crater retreat, slot and massfire, and modified VCR stoping tech- niques are used at Porgera. Stopes are backfilled with a relatively strong cemented rockf ill. Future stope sequences require recovery of pillars beside and under filled stopes.

Jan 1, 1991

By Garnsey R. G T, Wenk G. J, Toop A, Sowerby B. D

A bulk mineral analyser (BMA) suitable for the determination of Cu or Ni in bulk ore samples has been developed at the Lucas Heights Research Laboratories. This analyser, which uses the nuclear resonance scattering technique, is highly specific to the wanted element. The technique has previously been extensively field tested for copper at Mount Isa, Queensland.The present paper discusses the field trial in 1982 of a commercial prototype BMA for nickel. The trial was undertaken at the lateritic nickel mine at Greenvale, Queensland. The BMA and its shielding, together with a laboratory spectrum analyser, were sited in the sample shed adjacent to the workings. Two hundred and thirty-eight ore samples taken directly from the mine blastholes were assayed by the BMA. The average mass of sample was 12 kg, metal contents varied from 0.2 to 3.5 wt/per cent Ni and 4 to 43 wt/per cent Fe and free moisture varied from 11 to 55 wt/per cent. A measurement took 10 min to complete, although this time could have been reduced at the higher nickel grades. The r.m.s. deviation between BMA and chemical assays was 0.09 wt/per cent nickel. Iron and bulk density were also determined by the BMA, r.m.s. deviations being 1.7 wt/per cent and 0.03 g/cmJ respectively. Similar results could be expected from a BMA in routine industrial use at other nickel mines.

Jan 1, 1983

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

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

By G de Jong, W Sunyoto, K Sari, P Silalahi

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Big Gossan mine is operated by PT Freeport Indonesia and is one of the largest stope-and-fill mining systems in the world. The Big Gossan deposit is a ~200 m wide, 1200 m long and 500 m high steeply north-east-dipping to subvertical skarn body at the Cretaceous-Tertiary Ekmai-Waripi contact. The copper-gold mineralisation, with a 1.3 per cent copper equivalent cut-off grade, occurs mainly proximal to the Ekmai-Waripi contact in the garnet-clinopyroxene prograde skarn at the base of the Tertiary Waripi formation and partly distal to the contact in the tremolite-actinolite retrograde skarn of the Tertiary Waripi formation.The Big Gossan stope mine is designed from 2540 m to 3020 m above sea level. Present active stoping operations occur at level 2540 mL to level 2640 mL and are done in a primary and secondary stoping sequence. The width and length of the stopes is 15 m and 20 m respectively, while the height of the stope varies between 20 m and 40 m, depending on the ground conditions. The stability of the stopes is visualised in the Mathew’s Stope Stability graphs. These graphs and actual Cavity Measurement Scanner measurements on the stope will predict and show the overbreak and underbreak, which affect the reconciliation of the mined stope and also the pillar stability between the primary stopes. Geological factors like major structures, joints, veins and alteration intensity are important factors that correlated with the stability of the Big Gossan stopes.CITATION:Sari, K, de Jong, G, Silalahi, P and Sunyoto, W, 2015. Stope stability at the Big Gossan skarn deposit, Papua, Indonesia, in Proceedings PACRIM 2015 Congress, pp 139–146 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

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

By Matthew I. G

A new process for leaching zinc sulphide concentrates with gaseous mixtures of SO2 and O2 in aqueous solution is described.The reaction of SO2/O2 with Rosebery, Mt. Isa, Broken Hill and Elura zinc concentrates yields zinc and iron sulphates, elemental sulphur and some sulphuric acid. Rates of zinc extraction are controlled by a surface chemical reaction without apparent interference from the elemental sulphur layer for SO2 concentrations up to 9 per cent in the gas phase. Pyrite in concentrate exerts an activating effect, possibly through galvanic interaction with the sphalerite. Metal extractions are dependent on SO2 and O2 tenors of the gas, particle size, and the acidity and zinc content of the solution, but are independent of the ferric ion level. Extractions also reach maxima at about 85°C.Generation of acid may be prevented by conducting the reaction in the presence of ferrous iron and at acidities of 40 g/l or greater. Zinc and iron levels in Elura lead concentrate may be reduced by leaching with SO2/O2.

Jan 1, 1981

By McLennan R. G

The principle of personal safety is as old as the human race. The application of this principle to industry is of much more recent origin, and may be said to be almost exclusively the product of the twentieth century. The enormous strides in technique and production mode prior to the turn of the century had been achieved without any real regard for the crippled human by-products of that expansive era. It was accepted that. accidents were inevitable and formed part of the price that must be paid for production. It was not until 1885 that the first Workmen's Compensation Act was passed in Germany making the employer financially liable for injuries suffered on his plant.With awakening social conscience came the first organised efforts to reduce accidents in industry. Early 19th century literature dealing with the development of powerdriven machinery and the growth of industry in Europe contains many references to the unsafe and unhealthy working conditions that accompanied the change-over from the home workshop to the industrial plant. By the year 1900, there were in Germany - and a little later in England governmental regulations dealing with the guarding of hazardous machinery. American industry, now the acknowledged leader in industrial safety, admits freely that when an organised safety movement commenced in that country, there was already a considerable amount of information available to them from European experience. The steel industry was well to the fore in this work, and in...

Jan 1, 1957

By Warren L. J

The effectiveness of shear-flocculation as a method for upgrading simple mixtures of ultrafine (1-11 \lm) scheelite and garnet was evaluated. Statistical methods were used in the design and analysis of the main test program.The stirrer speed, stirring time, and initial weight ratio were all found to have significant effects on both the recovery and grade of the floes produced. The particle sizes also had an effect on the final grade. There were several important interactions between factors which also affected the results. Optimum conditions for shear-flocculation were established, and under these conditions about 80 per cent of the scheelite could be recovered at a grade which depended on the composition of the starting mixture. Starting with mixtures containing 10 and 50 per cent scheelite, the best final grades were between 20 and 50 per cent and between 70 and 90 per cent respectively, the actual value depending on the particular combination of particle sizes.

Jan 1, 1977

NATURE OF ORETHE Edna May ore consists mainly of clean quartz of a moderately hard and tough nature. The gold content is "free" and fairly coarse, so that a large percentage is recovered by amalgamation. The ore is practically free from metallic minerals.GENERAL OUTLINE OF PLANT AND TREATMENTThe ore, received from underground in trucks, is broken by a jaw breaker, then stamp-milled, follow~d by partial filie-grinding in pans. Mercury is used both in the mill boxes and pans. The pulp, on leaving the pans, passes over amalgamating tables and is then elevated by tailings pulp to cone classifiers and separated into a sand and slime product, each product receiving a separate cyanide treatment-sand by leaching in vats and slime by agitation and decantation in a "Trent" plant. Gold solutions from both sand and slime are precipitated together by zinc shavings in the usual type of precipitation boxes. Accumulated slime is trucked from the dam to a vortex mixer and from this point receives with the cement slime the same treatment.ORE BREAKING AND TRANSPORTThe ore is trucked from the brace of the shaft along an overhead line to the breaker station. Hence it is, by means of a "kick-up" dumped upon a grizzly, set with 2-in. spaces, the oversize being broken by a 15 x '9 Fraser and Chalmer jaw...

Jan 1, 1919

By A Jewbali, J Phillips, C Boyle

Normal practice in the mining industry is the creation of a single geological model. These models provide a single interpretation of the geological and mineralisation domains. These interpretations infer the exact behaviour of ore domain contacts at shorter scales when resource definition drilling is done on wider scales and are thus locally highly uncertain. The interpreted geological model provides a single number for the volume and tonnes of mineralised material enclosed by the mineralisation envelope. It is on this single number for volume and tonnage that capital intensive mine development decisions (mine design and scheduling, stockpile strategy, waste management, closure planning, dewatering strategy, product quality, etc) are based. Some of these decisions require knowledge of grade variability for small volumes of material such as quarterly production periods. It is generally recognised that this information cannot be derived from single kriged geological models, but can potentially be modelled by conditional simulation techniques. Uncertainty in the extent and continuity of the mineralised envelope and its effect on grade variability for shorter production periods is thus recognised as a major source of uncertainty in new mine development.CITATION:Jewbali, A, Boyle, C and Phillips, J, 2013. Quantifying domain uncertainty for an iron ore deposit, in Proceedings Iron Ore 2013 , pp 157-168 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

AMONG the multifarious duties which fall to the lot of a mining engineer it is safe to say that there is none of more fundamental importance than the study of the ore-deposits on which it is thefunction of his profession to operate, inasmuch as the whole business of mining in all its complicated ramifications rests first of all on the existence of something to mine. -When the ore supplies in a mine fail, the enterprise comes to- an end, and nothing, therefore, is of more importance than a thorough understanding of the conditions under which the ore occurs, so that everything possible may be done to open up the mines well ahead of their immediate output requirements, and develop new ore reserves to take the place of that which is raised from day to day. The great aim which the mining engineer has to keep before him in his study of his ore-deposits is to obtain such a knowledge of them that he will have sound grounds for prediction as to how they will behave in parts of the mines which are well beyond the point of the pick. It is on his judgment of probabilities in this respect that mining operations are entered upon, and the more thorough his knowledge of all the factors affecting the problem, the more is the judgmentlikely to be a sound one. The test of any theory is experimental confirmation of the truth of predictions based upon it, and our aim should be to try to perfect our knowledge of the rules governing deposition of ores, so that our theories may prove themselves equal to the task of successful prediction.

Jan 1, 1909