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The progress of longhole open stoping (LHOS) at The Zinc Corporation, Limited and New Broken Hill Consolidated Limited (ZC/NBHC) is described. The design of a novel sloped wall longhole stoping method at NBHC which should allow the cuplete extraction of the orebody without the formation of pillars and with minimal dilution of the ore with sandfill is reviewed.

Jan 1, 1983

By Davis A, Song J

A review of the literature indicated that several studies have been reported on the dissolution of gold using iodide/iodine, bromide/bromine leaching systems. Although the reagent costs are much cheaper for chloride/chlorine (or hypochlorite) this system has not been fully evaluated. This study was conducted to evaluate the fundamental chemistry of the chloride/hypochlorite leaching system. The CHEMIX program was used to model the stability of various gold species existing in the solution. The gold dissolution rate at different conditions was determined using gold strips immersed in various mixtures of chloride/hypochlorite. Leaching experiments were conducted to test the extraction of gold from various ores (oxidised and copper-gold ores), showing a promising prospect for this technique in various applications.

Jan 1, 1992

DR. WARK, said: I have not come to Broken Hill to tell you how to conduct flotation operations; indeed, during my short stay here I have already learned much concerning the process, of the many difficulties which have been overcome, and of those still awaiting solution. My purpose to-night is rather different. All who have been concerned with the operation...

Jan 1, 1933

By Mauk JL, Arehart GB, Mathews SJ

The banded nature of the quartz veins which form the Empire lode at the Golden Cross mine, is perhaps their most striking feature. Petrographic studies show that significant differences occur between the bands in terms of textures, quartz grain size, calcite, adularia and kaolinite content, and the form, concentration and mineralogy of sulfide phases. The 818Oqu i values of individual bands within the vein material range from 7.3-10.9%x. Calculations show that the 818Oqäa,u values can be adequately explained by temporal variations in the system temperature, boiling and/or variations in the systems fluid/rock ratios.

Jan 1, 1995

The process of resource estimation of large precious metal deposits is illustrated by reference to major deposits now being mined or developed by Placer.The estimation procedure commences with building an appropriate model of the mineralization and proceeds through steps of data validation and geostatistical studies. It is important that the geologists most familiar with a deposit be involved with all stages of the estimate, and also prepare a manual estimate used to validate the kriged resource.Resource estimates are major exercises taking many man-months of work. The most time consuming part of this is usually construction of an appropriate three dimensional geological model. The data base for the resource calculations must be complete and checked for accuracy. The most appropriate estimation method must be selected.

Jan 1, 1990

By Amelunxen R, Finch JA

Flotation columns represent an important addition to flotation practice. Columns have largely replaced. conventional machines in molybdenum cleaning in Canada. Columns have been successfully tested on bulk copper/molybdenum cleaning at Gibraltar Mines Ltd. A rougher cleaner/scavenger cleanercombination was shown to be capable of giving higher grades and recoveries compared with three stages of conventional cleaning. A control strategy for the columns has been developed. An interaction between gas hgldup and wash water rate has been exploited to control performance.

Jan 1, 1985

Projections of metal requirements for Japan and the United States indicate growing competit- ion for Australia's mineral output and a critical need for continuing discovery of new reserves. These projections may be modified by economic, social and political controls - the most import- ant factor probably being a shortage and the high cost of risk and development capital. Changing ownership patterns toward joint ventures and increased state participation are anticipated. New developments in global tectonics and metallogeny delineate favourable zones for ex- ploration and permit establishment of priority search areas even in regions of poorly known geology. Declining ore grades and special character- istics to meet technological requirements may modify identification and evaluation criteria. A broad approach considering all environments of concentration within the geochemical cycle is re- quired within any metallogenic province. The exploration geologist must be able to integrate geological theory, mining technology and financial analysis to establish well defined exploration objectives, in terms of economic and geologic models, in concept-oriented programmes.

Jan 1, 1973

By Brown K, Francis D

The Yallourn Open Cut Mine has recently commenced mining operations in the new East Field which will supply the 1450MW Yallourn W Power Station for the rest of its 30 year design life. The authors describe the design and implementation process followed during the rehabilitation of the areas disturbed by works associated with mining in the East Field. One area of the East Field, the old external overburden dump, has been of particular interest and is discussed in detail. A discussion on the fire protection considerations is included as these are critical and often misunderstood as being contrary to good rehabilitation design practice. Finally, the development of a master plan for the rehabilitation of the Yallourn Open Cut in general, incorporating the East Field work, is discussed.

Jan 1, 1992

According to the temporal and spatial distribution of regional metallogenesis, the Pacific Rim can be divided into four global metallogenetic systems. The Asia-Australia W-Sn metallogenetic belt is the typical representative of intracontinen- tal metallogenetic systems. This belt resulted from Mesozoic and partly pre-Mesozoic tectonic magmatism, mainly re- lated 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 min- eralised ore types showing a definite spatial and temporal distribution from endogenetic to exogenetic. These metalloge- netic 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 Schommarz KH, Dunne RC, Goodall CM

Column cells are widely used today for the recovery of base metals by flotation. Their use for the flotation of iron sulphides has not been as rapid. Australia has pioneered the use of large rougher flotation columns. During the last six years, seven rougher columns have been installed on gold mines treating iron sulphides and the technical viability of this technology has been demonstrated. Laboratory column testwork on a gold bearing iron sulphide ore demonstrated the effects of both physical and chemical parameters. In general the large commercial columns operate over a broad range of conditions depending on the downstream treatment of the flotation concentrate. The addition of wash water to commercial columns is not universally applied and there appears to be a need for a better wash water System.

Jan 1, 1993

Silver-lead mineralization at Indooroopilly, Queensland, extends upwards from Upper Triassic rhyolite which intrudes phyllite-containing Palaeozoic mineralization.Sulphides and magma were emplaced in a special structural site which underwent dilational fracturing while surrounding rocks were block-faulted and compressed. This site lies at tbe intersection of dykes, faults, and a lineament adjacent to a Middle Triassic granitic stock.Structural controls at Indooroopilly are attributed to the effects of piston faulting. Exploration for similarly controlled deposits should be directed towards structural intersections near stocks or batholiths which have intruded mineralized belts. Priority should be given to structural intersections which were sites of block-faulting and igneous activity under compressional tectonic conditions.Favourable sites lacking surface mineralization may contain ore at depth as piston faulting produces 'blind' ore deposits.

Jan 1, 1976

By Mutton B. K

A systematic approach to the collection, presentation and application of structural geology data is employed in the extraction of narrow en echelon Ag-Pb-Zn orebodies by rut and fill stoping at Mount Isa. The aim is to locate, document and predict areas of adverse ground thereby enabling adequate ground support to be installed in advance of production mining. The important structural features are identified and their relevance illustrated by case histories of previous failures. The methods of collection, documentation and application of data are discussed.

Jan 1, 1977

A modular computer-based monitoring system for mines is dis-cussed. The system consists of the following modules : production moni-toring system HADES, methane monitoring system CMC, seismoacoustic and seismometric systems SAK and SYLOK, communication systems. The system enables one to compose flexible,` economic structures according to the specification of a mine. Application of microcomputer-based monitoring and control systems in coal preparation plants also is discussed.

Jan 1, 1985

A continuous casting machine, of the Concast curved mould design casting billets in four strands, was commissioned at the Newcastle Works of The Broken Hill Proprietary Co. Ltd., in November, 1967. Quality assessment of early casts from this plant indicated that steel cleanliness was sometimes inferior to that of equival- ent ingot cast steel. Extensive trials to develop a modified deoxidation technique were not successful in improving clean- liness to the desired level. A "contra-flow" gas shroud, to cover the steel stream between the tundish and the mould, was developed, and proved successful in achieving the required levels of product cleanliness. The inclusion content of six grades of steel ranging in carbon content from 0.10 to 0.70 per cent is examined, and an attempt is made to explain theoretically some of the results obtained.

Jan 1, 1972

By Shibata Y, Shimizu R, Fukushima A

Kobe is divided by the Rokko Mountains, runn- ing from east to west. The southern section of Kobe is highly developed in contrast with the northern section, but big, new residential pro- jects like the Hokusetsu New Town and Hokushin New Town are steadily being developed. To handle future traffic between the two sections of the city, the double-tracked Hokushin Line, now under construction, will connect the Shin Kobe Station of the Kobe Municipal Transit (Kobe's subway system) to the Tanigami Station of the Kobe Electric Railway. The locations of Kobe city and Hokushin Line are shown in Fig.-1 and Fig.-2 respectively.

Jan 1, 1987

Oaky Creek Coal (OCC) has embarked on an ambitious program to fast track the introduction of Trench Mining into its current mining operations. The project has the capacity to allow the extraction of reserves at stripping ratios, uneconomical by conventional mining methods.Trench mining using Continuous Highwall Mining (CHM) technology reduces the in-situ stripping ratio to 4:3; compared with a stripping ratio of 20:1 using conventional mining techniques.

Jan 1, 1992

By Hamilton TM

The Holocene Minninup shoreline is a coastal barrier system stretching from Bunbury to Busselton, in southwestern Australia. It has developed in a microtidal swell wave environment, under the influence of the post- glacial marine transgression and Holocene sea level variation. Barrier sediments thin rapidly across a shallow shelf, and consist of quartzo-felds- pathic sands with a minor skeletal carbonate component. Holocene shelf deposits are laterally extensive sheets overlying Pleisto- cene limestone. Modern carbonate production is small. Development of the Minninup barrier system has been controlled largely by low rates of sediment input from terrigenous and carbonate sources, late Holocene sea level fluctuati,.,s, and pre-existent coastal landforms composed of Pleistocene limestone. Modern controls on sedimentation are the refracted, shoaling swell wave regime, and onshore winds, which combine to promote nett northward longshore drift. Holocene barrier systems of the southern Swan Coastal Plain are of several different types. These include prograded sequences of beach ridges overlying shoreface sediments, such as is found at Rockingham and parts of Geographe Bay, and complex polygenetic systems typified by the Leschenault Peninsula. Pre- liminary investigations of the barrier stratigraphy of the Minninup shoreline indicate that both progradational and polygenetic sequences are present. The processes involved in shoreline development and heavy mineral accumulation are being studied using aerial photograph inter- pretation, beach profile monitoring, sampling, and granulometric analysis. This will lead to an enhanced understanding of the mechanisms of heavy mineral accumulation, and assist in the development of genetic models as aids for Exploration.

Jan 1, 1986

By Lennox A

In an attempt to increase underground productivity Coal and Allied has introduced a continuous haulage unit into it's Moonee colliery. A second unit is planned for Nallarah colliery in the near future. Both systems will be roof mounted or monorail type and manufactured by Joy Manufacturing Pty Ltd. The introduction of these machines is seen as a logical step in improving the efficiency of mining with continuous miners. This could be in conjunction with longwall mining in the rapid development of gate roads or, as in the case with these machines, as conventional development and extraction units. The advantages of the continuous haulage system are; Relatively low cost. 2 Ability to obtain high productivity in irregular or disturbed coal reserves not suitable for longwall mining. 3 Increased worker safety with the elimination of shuttle cars and the majority of trailing cables. 4 Increased productivity independent of soft or difficult floor conditions. At the time of writing the Moonee installation is 6 months old. The Nallarah machine is due for delivery March 1988.

Jan 1, 1988

By Clark I, Stockton N, Warren L

Nickel flotation circuits currently experience difficulties in recovering fine particles of pentlandite less than ten microns. By agglomerating these particles using shear-flocculation it is hoped to improve the recovery of these fine particles. A sample of massive sulphide ore from the Kambalda region was separated using magnetic separation to obtain a high grade pentlandite concentrate (> 90 per cent). This was finely ground to produce a sample with particles of 50 per cent minus 10 um in size. This sample was then shear-flocculated using a variety of reagents, including xanthates, dithiophosphate and mercaptobenzothiazole (MBT). The effects of reagent type and concentration, conditioning time, impeller speed and type, and pulp density were studied. Froth flotation tests were also conducted on the shear flocculated pulps to compare the effects of xanthate and MBT on the recovery of pentlandite.

Jan 1, 1992

By Williams J. D

Magnetite has been used in coal processing for many years and it is likely that its use will continue well into the twenty first Century. While magnetite is only a minor cost component in coal processing, the use of processed magnetite in dense medium separation is essential to provide the split of quality coal products which the markets of today demand. The occurrence of magnetite in Australia is relatively abundant, but a combination of its iron content, magnetic properties, quality and proximity to the coal processing plants is essential to provide a low cost product for use in the Coal Industry. The demand for more splitting of coal in coal processing may require more grades of magnetite, particularly as a finer grade lower specific gravity medium to separate the finer quality low ash coals.

Jan 1, 1991