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By McNabb K. E

Significant coal reserves in New South Wales lie under areas with steep topography such as valley slopes and cliffs. Subsidence predictions are difficult to make for these locations as existing empirical databases cannot cover all permutations of topography and mining geometry. Two dimensional numerical model alternatives are of limited applicability. Consequently a novel three-dimensional numerical model is developed including the detailed panel layout, realistic rock mass properties including the full stratigraphy, goaf behaviour and actual surface topography. Model results show the same trends as subsidence measurements from Baal Bone Colliery in the Western Coalfield of New South Wales.

Jan 1, 1992

By K Niyomjinda, B Etschmann

Chatree Gold Mine is currently the only modern day gold mine operating in Thailand, and is situated approximately equidistant from Chiang Mai in the north and Bangkok in the south. Environmental guidelines set by the Thai authorities require Chatree Gold Mine to achieve a Total Cyanide level of 20 ppm or less in the process plant discharge slurry stream prior to release into the tailings storage facility. This paper describes both the initial difficulties faced in achieving compliance on this limit utilising the conventional INCO SO2/Air cyanide destruction system and the subsequent process improvements initiated to both the leaching process and the standard INCO process to achieve the current compliance levels of approximately 99/100 shifts. Improvements were focussed on the dual aspects of reducing the formation of WAD cyanide and ferrocyanide species in the leaching circuit coupled with process changes to improve removal of the ferrocyanide species from solution during the cyanide reduction stage.

Jan 1, 2004

The discussion in this paper centres on examples of mining that are drawn mainly from the coal mining industry. The intention is to review the opportunities that exist for incorporating environmental planning into mining industry practice in New Zealand. The coal mining examples serve to make some general points which have some application for many types of mining.

Jan 1, 1981

The Century zinc deposit is located in Queensland approximately 250 kilometres north north-west of the provincial city of Mount Isa, on Lawn Hill Station and within 150 kilometres of the Gulf of Carpentaria.ThefirstMining Lease in this area was pegged in 1887. The Silver King vein is the largestvein deposit in the area and has produced lead and zinc, in addition to 74,000 ounces of silver during its history.A total of forty three veins containing silver, lead and zinc are now known, all of which were discovered by prospectors within 10 years of the first vein being recognized.

Jan 1, 1993

Kalgoorlie is the main mining centre of the Western Australian Goldfields. Its famous Golden Mile' has been noted for the exceptional width and richness of its goldtelluride lodes. Since the mid-1890s production on the major mines has been maintained practically continuously.Rich ore, though not as plentiful or as rich as formerly, is still (1948) being mined in places. Unexplored areas still remain within the main auriferous belt which offer reasonable chances of success with intensive exploration.Much detailed information has accumulated in recent years through the geological mapping of underground workings by some of the larger mining companies. The purpose of this paper is to correlate observations made in most of the accessible old and recent workings in the mines of the Lake View and Star group and elsewhere.GENERAL GEOLOGYRock TypesThe rock formations are:-1. Fine-grained (older) greenstones, locally referred to as calc schists. There were originally pillow lavas and other flow rocks of basic composition, now extensively chloritised and/or carbonated. Pillows and fragmental flow- tops are recognisable. Intercalated with flows near the top of the series are several beds of sediments.2. Graphitic slates and other more arenaceous sediments.Although referred to as slates, they are rarely more than well-bedded shales with poorly developed fracture cleavage:Thick bands of felsitic rock are found in places.

Jan 1, 1952

WHEN making comparisons of the efficiencies of different grinding and crushing machines it is desirable to be able to estimate the work actually done in crushing the ore from a given size of feed to a given size of product, the screen analysis of both feed and product being determined. Messrs. Klug and Taylor, in a paper on this subject, published in the monthly journal of the Chamber of Mines of WA, 31st January, 1906, have described a method adopted by them in calculations made in connection with a series of trials of grinding pans. Their methOd is based upon the assumption that if a quantity Q of material consisting of particles of average diameter x be crushed down until the average diameter of the particles is y, then the work done in grinding is proportional to Q x. There is no theoretical basis for this assumption that the writer is aware of, and it does not appear to satisfy the fundamental conditions necessary. If the material be further crushed until the diameter 2 becomes Z, the additional work done is measured. The work done in crushing from diameter x to diameter Z in one operation is proportional to Q x:, and therefore we ought to have zx2 y2 x2 Q-+Q-=Q-. y2 Z2 Z2But these expressions are not in general equal to one another. In other words, according to the theory underlying this method, if we crush from diameter x to diameter y, and then from diameter...

Jan 1, 1909

In the extraction of level bridge pillars in the South Mine by square-setting methods the general practice is to work transversely from the hanging wall in narrow sections three or four sets wide to the depth of the bridge-usually three sets. When the working block attains an area of twelve square sets, sand filling is run in, either by pneumatic (Proceedings No. 123, 1941) or hydraulic methods, in order to control the settlement of the general area and prevent the development of undue weight in the stope. Upon completion of the filling operations, or coincident with them, ore breaking is resumed and the transverse section of the bridge pillar gradually reduced. A number of these parallel sections may be working at the same time.In preparing a block of sets for filling a great deal of paddocking is required, both to contain the filling and to preserve access to ladderways and ore chutes which may be situated at some horizontal distance. Stope paddocking until recently was constructed of 10 in. x 2 in. boards nailed...

Jan 1, 1942

By X Qiu

According to the temporal and spatial distribution of regional metallogenesis, thePacific Rim can be divided into four global metallogenetic systems. The Asia-Australia W-Sn metallogenetic belt is the typical representative of intracontinental metallogenetic systems. This belt resulted from Mesozoic and partly pre-Mesozoic tectonic magmatism, mainly related to S-type granite of crustal source that was generated by collisional orogeny combined with oceanic subduction in intracontinental and continental margin settings. Based on the concept of metallogenetic series, there is a group of mineralised ore types showing a definite spatial and temporal distribution from endogenetic to exogenetic. These metallogenetic series are widely distributed in the Asia-Australia W-Sn metallogenetic belt, and are well developed in Southeast China. Five metallogenetic series and two petro-minerogenesis evolution models have been established according to their tectonic settings, various types of granitoids and metallogenetic evolution.

Jan 1, 1995

By Walton DR

It is self-evident that the availability of well qualified and experienced people to manage mining operations is vital to the success of an individual mine and to the ability to develop new mines either in Australia or overseas. For larger operations the term "mine manager" is here used to denote a range of positions within an individual company. Thus "mine managers" may be people managing individual mines at one geographic location with overall management provided by other "mine managers" in the roles such as mine super- intendents, production managers, general managers, etc. Smaller operations may have only a single level of management nominated as "mine manager".

Jan 1, 1980

Spectrum Resources commenced operations as a public listed mining company in August, 1983, with a variety of precious metal projects in New Zealand. At that time the outlook for most mineral commodities, with the notable exception of precious metals, was decidedly gloomy. Metal prices were depressed and demand forecasts were universally gloomy. Against this background the company reviewed the non-traditional metals sector to try and identify a 'new' metal with an above average demand growth and market value. Lithium, a commodity with exciting new applications in storage batteries and alloys, met both criteria. Annual world consumption of lithium is around 7000 tonnes; current prices are around $NZ40/lb for lithium metal and demand growth is projected at five to seven per cent per annum. Geothermal fluids at Wairakei and elsewhere contain anomalous amounts of lithium and in May, 1984, the Chemistry Division of DSIR was commissioned to carry out a literature survey on the possible recovery of lithium and other minerals from geothermal waters. The survey results were encouraging and the company subsequently negotiated exclusive access rights, for research purposes, to geothermal discharge fluids from the Wairakei and Kawerau geothermal fluids. Most of the subsequent investigations reported here were carried out by Chemistry Division, DSIR, under contract to the company with some assistance from the Industrial Processing Division, DSIR.

Jan 1, 1986

For establishing sustainable material cycle process in human system, a brand new concept should be created, which could recycle the waste materials, which are land-filled and discarded under present economical situation. The concept of 'RtoS' (Reserve (of waste) to Stock) to create 'artificial deposit' of the materials concentrate is one of the best ideas to be applied. From this viewpoint, separation technology, in especial, solid phase separation such as mineral processing technology contributes much to the concentration, making 'artificial deposit' with less energy consumption compared with melting and/or dissolving technologies. Results of rare metals concentration in the e-waste are also introduced as an example with combining novel comminution and parts/powder separation.

Sep 13, 2010

Intensive exploration for iron ore in the banded iron-formations (BIF) of the Pilbara region of Western Australia began in the early sixties and almost immediately established the Hamersley area as a major iron province. The early genetic models for the BIF-hosted ores were based mainly on macroscopic examinations of ores from the "hardcap" zone, and generally accepted a direct relationship with weathering effects on a Mesozoic to Tertiary land surface. Brandt (1964) was the first to suggest a difference in age between the high-grade hematite ores and the more common hematite-goethite types. He initially accepted a supergene origin for both, but later opted for a hydrothermal origin for the hematite ores. Apart from MacLeod (1966), the published views of the next decade reflect a largely parochial interpretation of individual ore bodies, centred mainly on supergene models but with some support for hydrothermal concepts. Except for Ayres (1971), none of the models were backed by detailed mineragraphic data. In 1976, an AMIRA-sponsored CSIRO group began a Province-wide investigation of the wide variety of ore types and BIF, with emphasis on geochemical and textural studies. The resulting conceptual model for a world-wide unified supergene and supergene-metamorphic hypothesis is generally accepted in the Hamersleys.

Jan 1, 1986

Cut and fillstoping using hydraulically placed mill tailings has become an essential feature of stoping operations in Kalgoorlie. ' Approximately 30 per cent of the total production is currently mined by this method. Fill is prepared by thickening or cycloning and is gravitated or pumped underground. The average pulp density is 70 per cent solids by weight, Recent cost reducing innovations are the use of steel passes, corrugated iron manways, polythene film sealing, and the replacing of vertical cement lined pipes with boreholes. TTTTTI rvr T Trim r l1TT

Jan 1, 1964

The New Zealand Minerals Industry Association was incorporated as the NZ Mineral Exploration Association in 1982, with a membership that consisted of the gold exploration companies then active in New Zealand . As its membership broadened, it changed its name to the Mining and Exploration Association in 1994, and more recently the Minerals Industry Association. It is a non-profit-making incorporated society relying on voluntary membership, and is not funded by industry levies.   It has employed a full time executive director since 1988 when Robyn Ross was appointed, followed by John Pfahlert (1991 - 1996) and now with Doug Gordon managing the Association.   The Association is one of a number of organisations that represent the mining industry in New Zealand. Others include the Coal Association of NZ (CANZ), the Aggregate and Quarry Association (AQA), The West Coast Commercial Gold Miners Association and Minerals West Coast.   NZMIA membership comprises the main exploration and mining companies that account for over 80 per cent of New Zealand Æs mine output, and nearly all of its exploration investment. Its membership has expanded from gold exploration to encompass exploration and mining companies active in coal, gold, aggregates and industrial minerals.   The Association has developed a National Minerals Strategy that determines its priorities, implemented via a Minerals Industry Advisory Committee. This group was established six years ago to advise the Associate Minister of Energy on issues relating to the long term development of the minerals sector in New Zealand.

Jan 1, 2006

Mine planning studies of iron ore deposits are often based on resource models generated by ordinary kriging. Ordinary kriging aims for local accuracy to minimise the variance of expected estimation error but this is at the expense of reproducing variability of the original sampling data. Hence mine planning studies using kriged models are likely to underestimate product variability, and the required blending and stockpiling capacity to reduce variability to an acceptable level. Instead, conditional simulation models of the main chemical variables in iron ore are able to reproduce likely variability to be encountered during mining and processing. This approach is demonstrated in a case study of the Weld Range bedded iron ore deposit in Western Australia, with a comparison of ordinary kriging and conditional simulation models. Conditional simulation models suggest that, compared with the single ordinary kriging estimation, there is likely to be far greater block variability for iron and impurities, a greater requirement for stockpiling and blending capacity, highest variability in initial years of mining and less variability in later years of mining for deeper ore. The conditional simulations provide a more realistic range of mining outcomes for production of high-grade ore, which may be seven per cent less than in the kriged model, as well as for lower expected project net present value (NPV). In year one, the kriged model is conservative for NPV; however, in later years two to five the kriged model has higher NPV than most conditional simulations, suggesting expected NPV based on the kriged model may not be achieved. For improved decision-making in mine planning, a complete range of possible outcomes from conditional simulations of the deposit should be considered rather than relying on a single kriging estimation that may be an end member case in the range of possible mining outcomes.

Jan 1, 2009

By Hale Y. M

Multielement reconnaissance geochemistry coupled with ground scintillation gamma ray measurements has been used to investigate the dispersion patterns of uranium and other major and trace elements in the arid Palmyrides region of central Syria. This region occupies an interplatform depression in the northern part of the Arabia Plate, upon which sediments up to 10 km thick have accumulated. Outcrops of strongly fractured Mesozoic and Cenozoic rocks form two major mountain belts, the northern and southern Palmyrides, between which is located the closed Ad-Daww basin, with a thick Neogene and Quaternary clastic cover. Among the various lithologies, phosphorites are well represented. Uranium and associated elements have been incorporated into the Upper Cretaceous and Lower Palaeogene sediments, especially the phosphorites, which are well represented in the region. These elements are derived from three possible sources, namely, sea water, Lower Cretaceous volcanism and metalliferous fluids leaking along taphrogenic lineaments. In and around the phosphorites, numerous traces of secondary uranium mineralization occur. Over 500 geochemical samples of outcropping rock, wadi and playa sediments, overburden and groundwaters were taken over an area of approximately 9000 sq km. Most samples were analyzed for 25 major and trace elements by nebulization ICPAES; for As, Sb, Bi and Se by hydride generation and ICPAES; and for U, Th and La and other REE by neutron activation analysis.

Jan 1, 1988

As this district is so far distant from the other mining centres and its mode of approach so circuitous, I am afraid that many residents of other portions of the Commonwealth never think of paying this" Australia's Silver City" a visit, to learn personally the many and various lessons everywhere available, and to become familiar with the really wonderful and interesting features and deposits (which pature has so lavishly bestowed in the mineralogical world) yet seemed to almost ignore or overlook when disposing of topogr,aphical beauties of landscape and vegetation) unless professional or business duties require their presence here. So it is to those whose life is necessarily spent in other parts of the States where they answer their call of duty, and yet feel an interest, either for business or other reasons, that my paper is specially addressed and prepared, and for that reason I witl endeavour to make my remarks more of an explanatory than a dictatorial nature. I feel sure that there. are many members of our Institute who are much more familiar, and have had many more years' experience in the various methods of timbering, filling, and ore extraction, etc., than myself, but I hope that over I6 years' experience in connection with mines and engineering works, the last six of which have been spent in Broken Hill, where, I have been very closely connected.

Jan 1, 1903

In choosing such a threadbare subject for a paper I fear that I may in some measure be taxing your patience, yet as upon the accuracy with which the work is done depends the result of conclusions drawn as to whether a property will be profitable to work or otherwise. The subject cannot be too well threshed out, and I trust that upon certain points that have come within my own experience I may be able to give 'hints that will prevent others from making mistakes. First as to alluvial. Gold is often found from the grass roots down, often ill particular horizontal bands in the wash, but more generally concentrated either on a true or false bottom. When sampling dry ground for proposed hydraulicing I have obtained accurate results only by taking the whole of the dirt from measured shafts, stacking it as it was lifted on a tarpaulin, and putting the whole quantity through a carefully constructed box. In wet ground careful borings will in most cases give fairly correct results, but where it is possible to sink shafts, that should be done, as a guide is then also obtained as to the nature of the wash, whether it is bouldery, cemented, or free. Sampling in a face is a more difficult work in many respects than in new ground, as so many elements enter into action to spoil accurate sampling. Of course the great thing to avoid is sampling in any place where either natural or artificial concentration has taken place, and very much has to be left to circumstance and the sampler's own judgment. In passing I may mention that I have on several occasions seen diggers deceive themselves in wet ground where they were sinking and coping as best they might with water. They would take a dish of dirt from the bottom of their hole, pan it off, and take the result as a fair yield, and on the strength of it perhaps spend a lot of time and money in tail races and whereas in their sample there had been a process of concentration carried on, the movement and working in the water had caused the gold to work down, and anything like accurate estimations by the method pursued were out of the question.

By E Jak, J Chen, B Hogg, S Nikolic, S Nicol

The quantity of post-consumer ‘waste’ materials generated each year is rapidly increasing. These materials can contain significant quantities of critical metals and present an environmental challenge if landfilled. The ISACYCLE™ technology is a proven solution for the processing of these materials. In the ISACYCLE™ furnace, the post-consumer materials are processed to recover energy along with any contained critical metals, in the form of a base metal alloy or matte. In addition, a clean aggregate (slag) is generated, which has the potential to be used for a range of applications in the construction industry. This slag is commonly based on a fayalite slag but is modified to manage the complex feed. This paper will review the fayalite slag system and the theoretical modifications required for treating urban wastes. Slags from an ISACYCLE™ furnace processing urban wastes have been sampled and characterised. The chemistry of these samples will be reviewed and compared to the expected theoretical modifications required.

Jun 19, 2024

Mineral exploration and mining in New Zealand has had almost five years of new legislation. The requirement for different consents is a challenging, time consuming, expensive exercise but in most cases the new procedure is working, although the matter of obtaining access to land is still a major issue. Priority is critical. After lodgment of an application for a minerals permit there are many other matters to address such as identifying land owners, occupiers and administrators, preparation of access applications, consultation and preparation of various resource consent applications.

Jan 1, 1996