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THIS paper is the outcome of experiments carried on and experience gained. at the Waihi-Paeroa Gold Extraction Company's tailings plant at Waihi, New Zealand. The plant was erected to treat accumulated tailings which had been discharged into the Chinemuri River by the Waihi batteries.The Chinemuri River is a common sludge channel for all mining debris, tailings, and ashes from the power plants, the last being the cause of occasional high residues, which gave so much trouble to the management. The tailings were dredged from the bed of the river into barges by means of a Pohle air lift, the power being supplied: by a 13 b.h.p. Tangye oil engine driving an air compressor and a centrifugal pump. The sands were elevated from the barges by bucket-belt elevators over screens, to eliminate large particles and rubbish, into storage hoppers, and from there fed direct into four C. Judd Ltd. tube mills.The method of treatment was fine grinding in a weak cyanide solution, agitation in B. and M. tanks, filtration with turn-over vacuum filters, and precipitation with zinc shavings. The comparatively high values of the residues in gold gave a great deal of trouble, 'and it was not until repeated experiments were carried out that the cause of the trouble was located. While the value of silver residues remained stationary, the gold values...

Jan 1, 1912

The mining of high-grade narrow vein deposits is a predominant field of activity in the precious metal sector. These types of deposits are located throughout the globe and have a significant presence in mining operations. The principle factor that has undermined the profitability and effectiveness of mining such ore zones is the substantial dilution that occurs when blasting with explosives during extraction. In order to minimise ore dilution, the thermal fragmentation mining method enables the operator to extract a narrow mineralised corridor, 30 cm to 1 m wide (according to the true width of the ore vein). By inserting a strong burner powered by diesel fuel and air into a pilot hole previously drilled directly into the vein, a thermal reaction occurs spalling the rock and enlarging the hole to 30 - 100 cm in diameter. This patented method produces highly concentrated ore, resulting in 400 - 500 per cent less dilution when compared to conventional mining methods. The mining method was conceived with the aim of mining ounces, not tonnes. This method of extraction, reduces the environmental impact of mining operations since much smaller quantities of rock are displaced, stockpiled, and treated using chemical agents. The fully mechanised equipment operated by a two-person team, maximises the effectiveness of skilled personnel, increases productivity, and reduces risks of injuries. Important economic benefits are generated for large- and small-scale mining operations alike. For large-scale operations, the mining method increases mining reserves, lowers the cost per ounce, and increases the total profitability of existing mine operations. The method also significantly lowers costs and risks of developing and mining small-scale deposits, requiring less investment capital, shortening the payback period, thus reducing the lending risk.  Combined with a small modular processing unit able to process between 100 - 300 tons per day, the method substantially lowers the financial break-even point for small-scale mining operations in a narrow vein environment. The company has been working with the technology at its Rocmec 1 mining site; results achieved and future developments are discussed.

Jan 1, 2008

Mining companies in order to compete and succeed in being viable business propositions must look to the future and select mining methods which guarantee improved efficiency and productivity as well as lower costs. A mining company in adopting a method of mining must now select the equipment most compatible. To some mines compatible equipment may mean the use of drilling jumbos to replace hand held rock drills or the use of load haul dump units to replace scrapers. To other more mechanised mines compatible equipment may mean the use of raise borers and road heading machines. The right decision will be where equipment compliments method in such a way that the working environment is improved, productivity is maximised, cost if reduced and all profit opportunities are optimised. An example of such is where the use of improved mining techniques in underground operations may see cut off grades reduced. By selectively mining these lower grade orebodies, smaller operation's ore reserves improve and the capacity for continued growth is enhanced.

Jan 1, 1990

The Sons of Gwalia Mine in Western Australia is situated about 140 miles north from Kalgoorlie in arid country, where supplies of fresh water are difficult to obtain.Mine salt water is used throughout the treatment plant, whilst fresh water for domestic, boiler, and power purposes is pumped from a number of shallow outlying wells. The waters from all wells are constant in character, although they vary in the quantities of salts contained.An average sample of mixed waters gave the following analysis (Gr. per gal.):Sodium chloride 70.82Magnesium chloride 33.03Calcium chloride 26.98Calcium carbonate .. 11.57Calcium sulphate 22.71Iron oxide and alumina 2.10Silica and insoluble 4.58When this water is used in the boilers in its natural state it is scale-forming and intensely corrosive.

Jan 1, 1927

By P Allen, E Gleeson, D Boakye, R Chesher, S Konopa

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Not only do epithermal gold deposits provide many challenges in estimating mineral resources, the complexities of these deposits also provide technical challenges in assessing appropriate mining and processing strategies, as well as social and environmental planning and management. The characteristics of epithermal gold deposits include being highly variable with respect to geometry and gold grade distribution, the presence of other economic contributors, mineralogy, texture, rock strength, weathering and alteration overprint. These characteristics influence the economic value of mining projects in an interlinked manner. Consequently, successful exploitation of epithermal deposits requires a holistic approach, coupled with the effective integration of geological data to meet all aspects of mine development decision-making. This paper presents examples of the key technical challenges encountered in estimating and mining epithermal deposits. It also highlights why these issues need to be addressed from the viewpoint of geology, sampling, resource estimation, mine planning, mineral processing and social and environmental planning for the true value of the mining project to be realised.CITATION:Konopa, S, Chesher, R, Gleeson, E, Allen, P and Boakye, D, 2015. Challenges in maximising the value from epithermal gold deposits, in Proceedings PACRIM 2015 Congress, pp 127–132 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

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 J A. Sanchidrián

The general ranges of validity of some distribution functions are assessed from their behaviour with 119 sets of fragmentation data from bench blasting obtained by sieving. The emphasis is on determining the lower size/passing limit that the size-scaled Rosin-Rammler, Grady and Swebrec functions, and their bi-component versions, can represent with reasonable precision. By fitting these functions to the data using different weights, the accuracy of the fit varies in the different size/passing zones, so that an overall knowledge of the capacity of the function is obtained across the whole size range, from the coarse zone to the fines. Reasonable ranges of use of bimodal Rosin-Rammler and extended Swebrec (all of them five-parameter, bi-component distributions) are, in terms of percentage passing p, 99 > p > 2 per cent (up to 100 per cent for the extended Swebrec), or 90 > p > 0.5 per cent, in which the expected error of the calculated size is below 15 per cent in the extremes of the range, and less than five per cent in most of the central range; maximum errors (ie errors that will only rarely be exceeded) are typically less than 50 per cent in the central range, and up to about 100 per cent in the extremes. Ranges of use for the Swebrec and the size-scaled Rosin-Rammler (three-parameter distributions), with only slightly larger errors than the bi-components, are 100 > p > 5 per cent or 80 > p > 2 per cent. The classical two-parameter Rosin-Rammler can be used in the range 95 > p > 20 per cent or 90 > p > 10 per cent, with expected and maximum errors less than about 15 per cent and 100 per cent respectively.CITATION:Sanchidrián, J A, 2015. Ranges of validity of some distribution functions for blast-fragmented rock, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 741–748 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

The Myra Falls minesite, of Westmin Resources Limited, is located at the geographic centre of Vancouver Island, within the confines of Strathcona Provincial Park. The operation includes two active underground mines, II-W and Lynx, together with a modem 3650 1/d milling facility. Recent exploration successes will lead to the commissioning of a third mining area in late-1993 - The Battle/Gap Mine. These ore deposits are complexly metal-zoned volcanogenic massive sulphides of Devonian age, hosted in the Myra Formation of the Sicker Group volcanic assemblage. Three distinct felsic volcanic units are defined within the 450 metre thick Myra Formation. They are, from oldest to youngest, the H-W Horizon, the LMP Horizon and the Upper Rhyolite Unit. Massive sulphide mineralisation occurs throughout the property in the H-W and LMP Horizons. There are a number of orebody types, including polymetallic massive sulphides, polymetallic disseminated sulphides, zoned pyritic massive sulphides, elastic sulphide zones and stringer sulphide zones. Individual orebodies range in size from 10 000 tonne zinc-rich polymetallic lenses to the ten million tonne, zoned massive sulphide H-W main lens. The property has been in continuous operation for 26 years, producing over 13 Mt of ore averaging 2.2 g/t Au, 64.0 g/t Ag, 1.9 per cent Cu, 0.6 per cent Pb, and 5.6 per cent Zn. Current geological reserves stand at 12.5 Mt at a comparable grade, including 4 Mt of recently discovered high grade ore in the Battle and Gap Zones. Mining and milling methods have evolved over time to enable successful extraction and milling of these complex ores. Change is on-going with the recent conversion of the H-W Mine to large-scale bulk mining methods, and the development of effective computerised ore reserve calculation and mine planning tools. These changes, in concert with successful exploration techniques that led to recent high grade ore discoveries, have breathed new life into the operation and should assure its present and future viability.

Jan 1, 1993

Although these subterranean cavities are common to the Broken Hill big lode, yet the Broken Hill Proprietary is the most prolific in their occurrence, loud they have been found of various dimensions almost from the surface down to the lowest levels yet attained in that mine. Many of these vugbs have contined valuable silver, copper and lead deposits, and some have been remarkable for the beautiful forms of crystallization pendant from the roofs and walls, and collected on the floors. The question arises, How are these caverns and fissures in the ore body formed? There are numerous theories more or less feasible, but that the causes are variant is demonstrated beyond doubt. That water in its passage leaving channels, is one ofthe chief factors for their production is assured, and their presence is likewise due to the shrinkage and dropping of the earth from varions causes, to the deposition of material forming ledges overhanging, and thus leaving spaces below, and also to chemical erosion and electrical action both of which latter are constantly at work in reconstructing, segregating and dissolving tlie mineral and metallic constituents of all ore bodies.One of the most remarkable vughs yet discovered in the big mine was that opened up about three months bitek in the' heart of the ironstone body on Block 11, and located about 40 feet below the 100 feet level of Weatherley's stopes, but now destroyed in the progress of work. Probably it was caused by chemical action, the eating out, so to speak, of a soft and soluble portion of the manganic iron, leaving a,hollow about 15 feet long, with a width and height, of say, 6 feet, carpeted with beautiful zinc with a modicum of limeincrustations, apparently produced by the percolation from around the carbonate waters holding these minerals in solution. This cavern was divided into, what might be termed, a double chamber, by big boulders of manganic iron, also coated with an aggregation of small crystals of zinc and lime although the actual proportion of the latter was not determined.

Winzes are usually sunk 9 ft. 6 in. long by 6 ft. 0 in. wide and are divided into two compartments, 4 ft. 0 in. by 5 ft. 0 in. inside the timbers. The general practice is to sink the winze to a depth of from 9 to 12 ft., put in bearers and three or four rings of timber, and then erect a sinking headframe before continuing sinking operations.GENERALThe main feature governing the design of the headframe was that all parts could be transported on timber trolleys in No. 2 Shaft. Except for some minor details the structural members consist of steam pipe. Joints are sections of steam pipe welded to one member and into which the other member fits and is held in place by a 1-in. bolt. The headframe consists essentially of two bedpieces to carry the winch and to form a seat for the four legs. The legs support the sheave bearers, the tipping door and the brace.Except during tipping operations the door is in a nearly vertical position. For tipping it is lowered to an inclined position and a hook suspended from one of the bracing members of the headframe is attached to a "D" welded to the bottom of the kibble. This causes the kibble to tip when it is lowered on to the tipping door. The capacity of the kibble is 4 cubic feet.THE HEADFRAMEThe dimensions of the headframe are:Height to top of sheave .. .. 14 ft. 10 in.Distance centre to centre of legs 4 ft. 4 in.Length of bedpieces .. .. .. .. 8 ft. 9 in.The weight is approximately 2,000 lb., the tipping door and bedpieces being the heaviest members. They weigh 240 lb. and 170 lb. respectively.One compartment of the winze is decked over, and the bedpieces, which are 8 ft. 9 in. lengths of 6 in. pipe with three short lengths of plate welded to the underside, are placed over the sinking compartment, either transversely or parallel to the winze. Three 3 inch pipes act as spreaders between them.Welded to the top of each bedpiece is a 6-in. by iHn. plate 3 ft. 0 in. long with four 4-in. by 1.5-in. slots cut longitudinally at 10 in. centres. Two 10 in. by 4-in. timbers are bolted to these plates, the distance between them being adjusted to suit the holes in the winch bedplate, which is bolted to the 10-in. by 4-in. timbers.Two short lengths of 3 in. pipe are welded to each bedpiece at 4 ft. 4 in. centres. These form the seats for the legs of the headframe, which are...

Jan 1, 1941

Early strategic mine planning includes decisions over the organisation of work and workforce accommodation. These decisions involve significant commitments that affect not only employee quality of life but also the impacts and relationships with existing local communities. Strategies for workforce accommodation are characteristically community-based (either as purpose-built company towns or integrated within existing local communities) or commuter (fly-in, fly-out) mine camps. The quality of accommodation underpins the fulfilment, morale and motivation of employees. This is not only relevant to productivity and safety, but also to recruitment and retention, particularly with the current onset of a significant human resources crisis. In the event that communities exist in proximity to a proposed mine then the accommodation strategy selected can influence the value-adding potential for the sustainable development of such communities. This early planning is particularly challenging where mine locations are isolated and/or face significant economic, social and political adversity. This paper draws upon a case study review of five large mining projects implemented in three South American countries, selected to cover a range of scenarios and accommodation strategies. The review aims to advance our understanding of the complexity of the underlying planning issues. Each scenario considered the prevailing environmental, social, economic and political situation, together with the adopted accommodation strategy. The case study review aimed to identify lessons learned and to make recommendations for advancing mineworkersÆ accommodation planning practice.

Jan 1, 2006

By P Cameron

MetPlant conferences have focused on ensuring mining projects are well designed then optimised to operate safely and effectively at the top end of world’s best practice to ensure shareholders are not just happy but delighted. This assumes the MetPlant was built right the first time. However, reality is, too often Plant Metallurgists (PlantMets) find after commissioning they are faced with the expensive task of correcting errors or modifying shortcomings to achieve product quality at name-plate capacity, i.e. get it right the second time. Why do companies spend good money to engineer an excellent feasibility study then allow “wise men” remote from the project team to impose cuts in budget and schedule, often under the guise of value engineering? Since mining is full of uncertainties, such actions can increase the risks of failure with the result that some MetPlants do not work well. Can PlantMets influence the remote wise men who often are also imposing the rules for lending and the required returns to appreciate the uncertainties of mining and their associated risks then let the project team get it right the first time? PlantMets can negotiate with the wise men from the outset of the project and bring them into an outer layer of the team where they can understand the risks then share responsibility and accountability to achieve the common goal of building a MetPlant which works well the first time and deliver the forecast profits. Since shareholders are not in the business to make losses they appoint a Board of Directors to deliver the best outcomes for the shareholders. Thus the Board should seek effective advice on the risk reward implications from the PlantMet before making their decisions.CITATION:Cameron, P, 2015. Do all metplants work well? PlantMets can ensure they do, in Proceedings MetPlant 2015, pp 2–9 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

In the latter half of 1973 a contract was given to Roberts-Holland Joint Venture for the stripping of the southern exhaust airway.The contract was carried out efficiently and relatively cheaply. It was completed 2 months ahead of schedule.The sinking stage and in particular the drilling jumbo proved to be a success and helped produce an above schedule stripping rate.No major problems were encountered with ground conditions or ventilation. A survey of the shaft showed the diameter to be within the set limits of 5·49 m ± 0·15 m.

Jan 1, 1974

By B Manda, K L. Sandvik, K Musiwa

Mining and processing of pyrite ore at Iron Duke Mine, north east of Zimbabwe, generates large quantities of acidic mine water as a result of the oxidation of iron sulfides on exposure to air and water used in the drilling and blasting operations. The acid mine drainage (AMD) contains elevated levels of dissolved Fe, Al, Mn and sulfate and has characteristic pH values ranging from about 0.50 to 3.00. Handling and disposal of such a drainage places significant impacts on the economics of the mining operation due to the corrosive nature of the drainage on infrastructure, the limitations placed on water reuse and discharge to the environment under a new law governing effluent discharge. Treated sludge at Iron Duke is chemically unstable, changing pH from ~7 to ~3 within four days after deposition in the evaporation ponds. The effluent does not meet the permitted level of neutral pH, 500 mg/l sulfate and less than 2000 mg/l total dissolved solids. Excessive acid seepage from the evaporation ponds has resulted in contamination of the ground water below the ponds area, which shows high mean annual levels of iron (368.67 mg/l), sulfate (1702.89 mg/l) and low pH (2.86) in addition to other pollutants. This poor quality seepage infiltrates into the nearby Yellow Jacket River, contaminating the public water source. Furthermore, a deterioration of the land area and vegetation adjacent to the tailings dump is also observed. Understanding the controls on the neutralisation of acidic drainage and long-term sludge stability after placement in evaporation ponds is essential to minimise costs of closure requirements and for the protection of environment and human health. This study examined the effects of the master variables pH, redox potential, acidity and alkalinity on acid neutralisation. The results indicate that ferrous hydroxides are not as stable as ferric hydroxides and that proper oxidation of iron also leads to better sludge stability, higher treatment efficiency and a manageable sludge viscosity. Metal hydrolysis and secondary mineral formation at the evaporation ponds under a wide range of pH and redox conditions is responsible for equilibrium shifts in metal reactions, resulting in high potential for metal leaching and mobility. Mechanisms of metal attenuation are also discussed.

Jan 1, 2006

By S Reid, W Chen, T J. Donohue, A Katterfeld

The use of discrete element modelling (DEM) is widespread in the materials handling field, and is used for many applications. One of the important limitations in using DEM is the number of particles that can be modelled, with this limitation often resulting in increasing the minimum particle size in the simulation. This restriction on minimum particle size is usually accommodated in the calibration process where the parameters in the simulation are chosen in such a way as to reflect the presence of smaller sized particles, and in typical applications such as transfer chutes this is standard practice. However, in the application of vibrating screens the inclusion of the ‘fines’ is critically important due to their influence on the screening efficiency. In reality, the presence of fines reduces the screening efficiency for a number of reasons; however, the main mechanism that will be addressed in this study is the effect of adhering fines. This is where the fines adhere to the larger particles and are carried over into the lump stream. The approach for this study will be to firstly consider the relatively simple mechanical sieving process used in the determination of particle size distribution, and then this will be expanded to consider the application of vibrating screens.CITATION:Donohue, T J, Chen, W, Katterfeld, A and Reid, S, 2017. Addressing the challenges associated with the modelling of iron ore in vibrating screens, in Proceedings Iron Ore 2017, pp 155–160 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

Leading Article from "British Medical Journal," London, 4th, November, 1944.Assuming that silica exerts its injurious effect upon animal tissue through a slow transformation into silicic acid, Denny, Robson, and Irwin thought that if the solubility of siliceous material retained in the lungs could be suffciently reduced the usual fibrotic response could be diminished or prevented. They discovered that aluminum powder rendered siliceous material insoluble in vitro by coating the silica particle with a thin film of gelatinous hydrated alumina, which on drying formed crystalline alpha aluminum monohydrate. The presence of this adsorbed layer on the surface of the quartz was shown by staining it with aurin. That metallic aluminum dust produced no fibrosis in the lungs was demonstrated by dust-inhalation experiments on eight rabbits. Attempts were therefore made to prevent silicosis by mixing quartz with metallic aluminum dust.Animals exposed to quartz dust developed typical silicosis in about five months, but the addition of 1 per cent. aluminum powder prevented this even after exposure had been lengthened up to 22 months, provided the aluminum powder was of a particle size below 5. This year Crombie, Blaisdell and MacPherson have reported the treatment of 34 silicotic miners by the daily inhalation of fine aluminum powder freshly ground from small aluminum pellets in a specially constructed mill. Daily treatment began with five-minute inhalations, which were gradually increased to 30 minutes. Some of the men received 300 treatments, but the majority only 200. Out of the 34 cases thus treated clinical improvement was manifested by lessening or disappearance of shortness of breath, of cough, of pain in the chest, and of fatigue. In 15 cases the condition became stationary and remained so in spite of continuous employment in silica dust throughout the treatment. The progress of the disease was assessed by means of tests for respiratory function repeated at three-monthly intervals. Obviously this treatment cannot be regarded as a cure for silicosis, since it cannot restore lung tissue which has undergone fibrotic change; but Crombie and his colleagues believe that the inhalation of finely particulate aluminum powder offers every prospect of preventing the development of human silicosis.In view of these findings, it is surprising that repeated papers by Goralewski from Germany describe various types of lung disease attributed to aluminum dust, and press for them to be scheduled under the Workmen's Compensation Act in that country. Seven hundred workers were investigated. They were making, probably by a stamping process, aluminium powder containing about four milliards of particles of dust per grain, and are reported as complaining of dry cough with pain on breathing, shortness of breath, poor appetite, and gnawing abdominal pain. Spontaneous pneumothorax developed in four workers. No abnormal physical...

Jan 1, 1945

By J Zhou

This paper discusses the implementation of a mixed integer linear programming model for a coal preparation plant. The plant considered consists of primary and secondary heavy media cyclones, hydrocyclones for intermediate fines and froth flotation for the very fine material. The model is designed to optimise the plant settings and product flows to maximise revenues for a given specification for two product outputs. The model can deal with bonus/penalty aspects of the product pricing for products that exceed or fail to meet specification. We report on a model with two separate coal feeds with parallel circuits for the oversize, intermediate and fines streams. The genesis of this model is more than 30 years old but recent improvements in mixed integer programming solvers make a full mixed integer formulation practical. The original model began as an enumeration of cut points with arbitrary rules for product allocation. The product allocation was improved in a linear programming formulation by Gunn (1982) and Sarker (1991 and 1995). Current mixed integer programming capabilities make it possible to replace the enumeration aspects and solve directly as a mixed integer programming problem. The current implementation uses a general purpose modelling language to formulate the model. Open source and commercial mixed integer programming solvers are compared

Sep 26, 2011

By Moeller T

The Bottle Creek mine, when opened next month, will consist of three open cuts, Emu, VB and Boags, feeding ore to a central mill. The open cuts cover a strike length of 4.5 kilometres which forms part of a linear structure, which can be traced geochemically for 26.0 kilometres. With the exception of a few small gossanous outcrops at Emu, the deposits are completely covered with insitu laterite and alluvial overburden. Since its discovery in 1984, the deposit has been subjected to three major reverse circulation (RC) drilling programmes which have successively closed up the drill spacing on the main mineralized zone to 25m horizontally and less than 25m vertically. All resource calculations have been based primarily on samples of RC drill cuttings from these programmes. Ore reserve calculations have been completed after each drilling phase. They began with a simple polygonal technique, progressed through two sectional half-distance calculations and are now being completed with a 3-D geostatistical technique. Because of the style of mineralization, Norgold personnel paid particular attention to assessing the variability of the mineralization by using repeat samples, repeat analysis and diamond drill vs RC comparisons. In addition, close attention has been paid to obtaining an accurate estimate of the global SG of the ore bodies. Particular care has been taken to obtain complete drill intersections of the orebody and to maximize wet sample recoveries. Extensive re-sampling and re-analysis of samples has confirmed that Bottle Creek is unusual for an oxidized gold deposit in that all the gold appears to be very fine grained, and evenly distributed within the mineralized zone.

Jan 1, 1987

By C Doblin

Any value addition to the mineral sands in the Murray Basin (Australia) will generate waste that needs to be disposed of safely. For example, conversion of ilmenite and synthetic rutile to titania (TiO2) pigment would generate large amounts of environmentally undesirable elements. Processing of U+Th containing zircon sands to zirconia or to higher purity zircon would generate a low-level radioactive waste. In this study it is proposed that one way to circumvent the waste problem could be to contain such waste in magnesium-based (Sorel) cements. Containment of waste in magnesium cements is an attractive idea especially for the mineral sand processing companies that could operate in the Murray Basin in the future, because the required magnesium oxide and magnesium chloride may be made cheaply from the saline waters encountered during mining operations. The magnesium cement production process is also far less energy intensive than the Portland cement production process. The results of this study indicate that mixing a waste stream with a slurry of magnesium cement before being discharged to the disposal area would contain the waste in a æconcrete-likeÆ structure, resistant to dispersion by wind and moderate rain. However, some loss of strength and increased leaching of impurities, Mg and Cl could take place in wet climate areas. Ongoing research is being concentrated to develop a new process for making water-resistant magnesium cement.

Jan 1, 2002

The subject of my paper is one which, I am certain, has exercised the mind of every man on whom depends the safe and economical conduct of mining operations; particularly in this district where the enormous size of the ore body has necessitated the mine workings assuming a scale that was hitherto unknown in the history of Australian mining. I, therefore, approach the subject with the feeling that I am displaying considerable t.emerity, knowing as I do that the subject has engaged the earnest attention and thought of everybody immediately concerned in the extraction of the ore of this district, and particularly of the Broken Hill lode.I think I shall not be contradicted in asserting that a very large proportion of eur accidents are distinctly traiceable to inexperience on the part of the miner, and records at the mines and verdicts of coroners' juries in many instances uphold this assertion by showing that the accident under notice was the direct result of lack of knowledge of the conditions of the work, or, at any rate, of an error of judgment hardly conceivable in the experienced miner. That this assertion is correct may also be proved by visiting any of the mines of the district.To the experienced eye it will be evident at once that a very large number are not in way skilful in the use of their tools and, therefore, lack the experience which of necessity must be coincident with the acquirement of skill. Now in making this' assertion, I do not intend to be too sweeping...

Jan 1, 1903