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THE question of dealing with the small quantities of copper found in a great many of the purchased ores became a factor of importance when the Sulphide Corporation decided to refine its own lead bullion, as the presence of this impurity has a marked effect on the efficiency of the de-silverizing operations of the Parkes process. Removal of the copper from the base bullion.The copper is removed from the base bullion by drossing, which collects the copper, and at the same time has considerable gold, silver, and lead values. The drassing of the bullion is done in two stages-firstly, at the smelters; and secondly, in thecopper kettles at the refinery. In both cases a "wet" dross is produced, which is subsequently "sweated" in a suitable type of furnace. When "dry" the dross is raked out and stored until enough accumulates to warrant a nUl on dross in the small blastfurnace kept for that purpose. A typical assay of the "dry" dross is as follows...WORKING THE DROSS UP TO LOW-GRADE CU-PB MATTEThe accumulated dross is treated in a small blast furnace with the necessary fiuxes, producing a low-grade Cu-Pb matte and base lead bullion.

Jan 1, 1920

By J Poniewierski, Varcos D

Efficient blasting requires constant vigilance with respect to the actual layout being used in the field. Objective measurement techniques are required in laying out a pattern as the 'by eye' or 'thumb suck' methods cannot guarantee consistent results in layout. Erratic blast results are the consequence of such an approach. In a case study at Sons of Gwalia mine, it was demonstrated that incorrect front burdens had a snowballing effect on otherwise carefully laid out blasts, resulting in both excessive amounts of boulders caused by preconditioning of bench fronts and tops, and tight digging. Both problems caused lower excavator productivity and excessive excavator damage, as well as making it difficult to set out subsequent blasts correctly. Several field measurement methods are available to aid in determining correct blast layouts and one is described in this paper.

Jan 1, 1994

By N Takamatsu

The environments surrounding the iron and steel industry have changed greatly in recent years. Reported in this paper are the technologies adopted by the Japanese iron and steel industry to fititself to change in global steel demands, degradation of iron ore and coal, prolonging service life of the facilities and requirements of energy saving. In addition, innovative technologies for CO2 emission control in iron making processes are also discussed.

Jul 11, 2011

By Haskard R. W

A method of raising has been developed at Cobar Mines Pty Ltd's CSA Mine which has achieved advance of up to 6 m in a single blast and raises are now developed which have averaged 4.2 m per blast. The method is a form of Long Hole Raising and is applicable to short raises of less than 50 m length. Blast holes are column charged and initiated sequentially with short delay detonators (millisecond). The equipment used to drill the raising blast holes consists of normal production drilling rigs and accessories and no other special equipment is required. The method has significant advantages in rates of performance and fits neatly into production drilling and blasting schedules. The method is also far safer than any non-mechanical or conventional means of Raising.

Jan 1, 1983

Joint ventures exist as a means of sharing risks and obeying regulations. An unincorporated joint venture allows a company to take a share only of a project yet allows that company to treat such share as though it were an integral part of the company. The nature of the risks inherent in many ventures is described and comparisons made with alternative corporate vehicles. Different procedures for managing joint ventures are also reviewed and the types of problem encountered in establishing and operating joint ventures are discussed. The basic characteristics of successful joint ventures, in Australia, are listed and a conclusion reached that, despite its difficulties, the joint venture will continue to proliferate as a corporate vehicle for project development.

Jan 1, 1983

By Doyle R

Underground operations commenced at Tower Colliery in late 1978 and the early prevailing mining conditions in the worked seam were considered poor as a result of high stress and geological disturbances. This suggested that outbursting activity may be a possibility. The colliery has since recorded a total of 13 individual outburst incidents, all of which have been associated with the same dyke and strike-slip fault zone. This paper depicts the geological conditions and presents the results of investigations undertaken at the time of these outbursts.

Jan 1, 1986

The initiation of cast Pentolite primers by detonating cord has been examined by the combination of two different experimental techniques with computer simulation by the finite element hydrodynamic code DYNA2D. In the first type of experiment, the cord/primer system was placed in a water aquarium, and photographed using a high-speed image converter camera. This highlighted the emergence of the detonation front through the primer surface and the generation of shock waves in the surround- ings. Numerical simulation was used to interpret the experimental record, establishing where the cord had induced buildup to detonation inside the primer. The second experiment used the plate dent test, where the primer was placed in contact with a block of metal (here aluminium), with the resul- tant dent in the metal surface being a measure of primer output. Detailed numerical simulation of this test confirmed that the observed dent was caused by the development of a complex series of shock waves inside the Primer.

Jan 1, 1988

By Cunneen R. D, Murray A. M

Exploration in the vicinity of the abandoned Mt Coolon mine has shown that the shape and attitude of the quartz lode is controlled by the interaction between the lode and a converging syncline. Gold grades within the lode are enhanced along intersections with a welded ignimbrite, and decline rapidly where the lode intersects unwelded ignimbrite. Mineralogy and textures indicate the vein has an epithermal origin modified by a later intrusive event.

Jan 1, 1989

This problem is seen as being central to a number of peripheral problems. Of these, the following are considered to be of major importance: 1. Reserves. Changes in Quality. Depths at which they occur. The effects of catchment and water storage areas. The effects of urban development. 2. Environment and the compat- ibility of mining and preparation of coal. 3. Transportation of Coal. J. tabour.

Jan 1, 1976

By Crawford G. R, Wold M. B

The application of the hydraulic fracturing technique to the measurement of in situ rock stress from underground excavation is discussed; including relevant theoretical considerations, equipmenl details, experimental technique and analysis procedures. Examples of the application of the technique at three Australian coal and metalliferous mining operations are given. The results obtained from these applications are compared with corresponding results obtained from overcoring tests conducted in close proximity at each site. Generally good correspondence in a wide variety of rock types is indicated. Experience gained with hydraulic fracturing at several underground mining sites has indicated it to be a quick, cost effective means of gaining an understanding of the in situ stress field in sufficient detail for many mine planning functions.

Jan 1, 1990

By Barber S

The Golden Cross Mine is located within the Waitekauri Valley near the southern end of the Coromandel Ranges, eight kilometres north-west of Waihi, North Island, New Zealand. The mine is owned and operated in a joint venture by Coeur Gold NZ Ltd (80 per cent) and Viking Mining Ltd (20 per cent). The underground mine produces gold and silver from low sulphidation epithermal quartz veins which developed in the shallow parts of a meteoric water dominated system during the Upper Miocene (7.36 - 6.67 Ma). The Empire Vein System is hosted within a dilational structural environment which developed at the lithological contact between acid intrusives, rhyolitic-dacitic tuffs and reworked pyroclastics, and undifferentiated andesites. The formation of the Empire Vein System was controlled by the rheological properties of the host rocks and variable displacement along a series of normal, right lateral, easterly-dipping faults. These faults represent sub-parallel zones of master shearing within a Riedel shear model. Underground mining extracts ore from the steeply dipping hangingwall and the complex footwall veins of the Empire Vein System. Initially sills are driven along the hangingwall vein on ten to fifteen metre sublevel intervals. In the footwall zones where significant mineralisation adjacent to the hangingwall sill drives has been identified, a series of cross-cuts and footwall drives (sub-parallel to the hangingwall sill) are also developed. Where continuity of mineralisation and ground conditions permit a combination of post pillar flatbacking and AVOCA longhole benching methods are used. Detailed underground mapping of lithology, quartz veining and major structures provides the information for designing ground support and footwall pillars, planning mine development and ore extraction sequencing. Sectional interpretation displays the vertical extent of faults, fractures and the vein system. The mining methods used underground at the mine have evolved through a thorough understanding of the structural complexity and the systematic geological mapping of the Empire Vein System.

Jan 1, 1997

By Russell F. M

Following the accident in the Peterson section of Mufulira mine in September, 1970, a method had to be found of extracting up to 300 000 tonnes of ore per month from this area without inducing caving. Sandfill mining methods were chosen, necessitating a plant capable of producing both cemented and uncemented fill on a large scale. The paper covers the design and construction of this sandplant which is thought to be unique for its size, as it incorporates three 3 000 tonne capacity settled storage silos, a 500 tonne capacity cement silo, mixing tanks and a control room situated underground. The plant is designed to handle an aver- age of 440 tonnes per hour with a maximum of 660 tonnes per hour for limited periods, delivering either uncemented fill or cemented fill in proportions varying from 1:6 to 1:30. The instrumentation and equipment necessary to give one man operation of the plant is described and the fill mining methods now in use at Mufulira are briefly outlined.

Jan 1, 1973

By Mauk JL, Arehart GB

Quartz veins from the Martha Hill epithermal gold-silver deposit, Waihi, commonly exhibit crustiform banded textures. Visual differences observed between bands are primarily the result of a 1 to 1500 ¦m variation in quartz grain size. Quartz band textures are dominated by anhedral interlocking quartz mosaics, commonly associated with minor adularia and sulfide phases; these textures are interpreted to be products of amorphous silica crystallisation. The occurrence of rhombic adularia suggests that prolonged boiling influenced parent fluids. In contrast, the presence of coarsely crystalline bands, made up of subhedral to euhedral quartz grains, infers primary crystal growth from solution; evidenced by the occurrence of growth-zoned quartz within these bands. There is a narrow range of 3.3%o in 618Oq,,,,,= between maximum and minimum isotopic values for the deposit. Significant overlap in 618Oqu,, values are observed between the Martha and Welcome lodes. However, statistically significant and commonly systematic differences do occur between individual bands analysed in most samples. Temperature fluctuations may be the dominant factor responsible for observed inter-band variation.

Jan 1, 1995

By Shoobridge PH

Operating difficulties during 1977 with the Imperial Smelting Furnace operated by Sulphide Corporation Pty. Limited at their Cockle Creek zinc-lead smelter were found to be caused by premature softening of sinter in the upper shaft of the furnace. This soft- ening was shown to be a consequence of raw materials and operating policies which led to unusually high levels of both lead and silica in a sinter of low basicity. A programme of softening tests and micro-examination of a range of sinters established that premature softening occurred when lead and silica increased to the point where a lead-calcium silicate with a low lime content became the major continuous phase in the sinter. This information was used to define a range of compositions which kept the softening temperature acceptably high for furnace operations.

Jan 1, 1978

By Bonsall EM, Schwabe MR, Hamlyn DA

Historically, most of the gold produced from Kalgoorlie has been derived from the gold and gold telluride Golden Mile lode systems dominantly hosted within the Golden Mile Doler-ite and to a lesser extent, Paringa Basalt. In more recent times the gold-quartz stockwork ore bodies within Unit 8 of the Golden Mile Dolerite at Mt Charlotte have become increasingly imp-ortant.Extensive low grade gold mineralisation has now been defined to the north and east of Kalgoorlie within rock units of the Golden Mile sequence not generally considered to be highly prospective.Two main types of mineralisation have been defined. The first comprises variably mineralised and altered quartz-albite porphyr-ies emplaced within talc-carbonated Hannans Lake Serpentinite (Mystery deposit). There is intense fuchsitic, pyritic and carbonate alter-ation of the serpentinite adjacent to the porphyry bodies. Gold mineralisation is assoc-iated with fine-grained disseminations and veinlets of pyrite and narrow quartz and quartz-tourmaline veining within the porphyry and adjacent fuchsite-carbonate rock. Several sets of vein directions are present, some of which typically exhibit sulphide alteration haloesnnA H] rhina_

Jan 1, 1984

A 1991 survey of 48 mining companies, employing more than 24 000 employees, showed that disabling injury and disease rates continue to be the most common measurements of safety management effectivness in the Australian mining industry.Of the companies surveyed, 22 claimed to be making regular safety audits. Of these only two listed the improvement of audit scores among their goals for 1991.Influenced by loss control management thinking, some managers have expanded the scope of their safety programs to include all accidental operational losses adversely affecting mine profitability.Learning from their new experience with total quality management some managers are now recognising that successful safety management outcomes depend on the effective management of program inputs. They are thus turning away from measurements of accident consequences - the failures of the management system - to measurements of management control.The new focus of safety management attention is now on corrective actions before accidents happen.

Jan 1, 1992

By J L. Mauk

The Favona adularia-sericite epithermal Au-Ag deposit is located at the southern end of the Hauraki Goldfield, about one kilometre southeast of the world-class Martha deposit. The deposit occurs in Late Miocene andesitic lava flows and local dacitic tuffs of the Waipupu Formation. In some places, post-mineralisation ash fall and ignimbrite, up to 50 m thick, cover mineralised rocks and andesite. We collected soils samples from 110 sites along eight traverses over Favona, and from three regional lines: two south of Favona, and one north of Favona.   Analyses of soils identify prominent enhanced concentrations of Au, Ag, and Hg, and lower enrichments of Sb and As. At Favona, Au and Ag appear to be highly anomalous in areas over mineralisation with Au concentrations greater than 100 ppb and Ag concentrations greater than 1000 ppb, whereas background concentrations are approximately 5 ppb and 50 ppb respectively. The background concentrations of Hg in soils are approximately 100 - 200 ppb, but in mineralised areas, Hg generally exceeds 200 ppb, and some soils contain greater than 600 ppb. Antimony shows enrichments, although weak, above known veins and As locally shows some enrichment above areas of known mineralisation. Therefore, soil sampling at Favona defines geochemical anomalies that correlate with the position of known mineralisation at depth. Thus, there is strong empirical support for the use of Au, Ag and Hg, and possibly Sb and As geochemistry to identify mineralised trends associated with buried deposits at other epithermal prospects.

Jan 1, 2007

In 1985 BMR assessed Australia's economic demonstrated resources of mineral sands as follows: rutile 8.0 Mt, ilmenite 41.4 Mt, zircon 11.5 Mt, and monazite 229 000 tonnes. These resources are located along the east coast of Australia, in the southwest corner of Western Australia, and in the Eneabba region, north of Perth, WA. However, over 40% of Australia's rutile and zircon resources, particularly those on the east coast, are presently not available for mining because of environmental considerations. As well, east coast ilmenite has been considered unsuitable for use by sulphate route pigment producers because of its relatively high chrome content. World demonstrated resources of rutile and zircon are estimated by BMR as 29 Mt and 38 Mt respectively. Demonstrated resources of ilmenite amount to about 1 billion tonnes. These occur predominantly in hard rock deposits in Norway, Canada, USSR and China, as well as alluvial deposits in Australia, South Africa and India. Quantitative data for world monazite resources is sparse. However, world production of rare earth oxides is now mainly from bastnaesite, a hard rock resource. Australia is presently the world's principal producer of rutile and zircon, and also provides a major share of the world's ilmenite. With the expected increase in Australia's rate of output of these commodities, combined with restrictions on mining along parts of the east coast, its position could diminish substantially over the next 25 years.

Jan 1, 1986

By Shunli Z, Jin X, Guanzhou Q

Flotation behaviour can be controlled, due to diminishment of granula quality and extension of specific surface area, by adding coarse particles (high- grade concentrates) to condition pulp. It has been substantiated that coarse particles can intensify fine particle flotation and its mechanisms are effects of carrier, intermedium and assistant aggregation of coarse particles. Calculation and analysis of Reynolds numbers and their variation for different size particles, under specific turbulent dynamic conditions, reveal that agglomeration among granulae is subject to specific turbulent dynamic conditions. Furthermore, sizes and adhesion strength of flocculated particles are the function of specific physical and chemical factors. Based on this research an innovative ramification carrier flotation process has been developed, which has been applied to Fankou Lead- Zinc Mine, Guang Dong province, China, etc, with satisfactory results. These results shed light on distinction between conventional flotation and fine particle flotation, meanwhile, provide a basic approach for further solution of fine particle flotation problem.

Jan 1, 1993

By Tapp B. A

The minerals industry in Australia is currently regarded as the country's economic saviour; the bastion of economic security. As Fitzgerald (1974) stated, 'Australia's natural endowments in minerals are the envy of most countries of the world'. As a result the proposed new mineral developments are on a scale that hitherto in the sixties would have been completely unenvisaged. It is reported that Australia is poised on the verge'of a sixteen billion dollar mining-based investment boom: a boom that will see Australia dominate the energy export field, the mineral processing field, and create the 'coal dollar'. This growth scenario has many inherent dangers, and it is the authors' contention that these should be carefully considered before further development proceeds. Two of the major problems related to the mineral industry growth scenario are the predictability of the future metal market, and the energy cost of mining. The latter problem is the one discussed here. The mining-mineral processing industries in Australia currently use about 36% of Australia's primary energy

Jan 1, 1980