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A review is made of the limited published experience of the effects of cemented fill in flotation.A general approach is adopted in listing and discussing possible sources of, and reasons for, ore contamination by cemented fill, together with basic, fundamental approaches to minimizing this contamination. These approaches involve basic mining design, effect of fill placement density, optimization of curing time and of cement content, variation of fill particle grading, use of flocculants and of pozzolans, fill placement and dewatering, and or blasting and handling practice.

Jan 1, 1974

Flotation testing has been done at laboratory scale on hematite mineral and ore samples using stage additions of various hydroxamates. Chemisorption of hydroxamate species onto the hematite surface was inferred from the results, possibly involving both the undissociated hydroxamic acid and hydroxamate ion as maximum recovery occurred close to the pKa of the hydroxamic acid. Flotation testing on a specular hematite ore containing 40 per cent Fe and 42.5 per cent silica gave highest iron grades in concentrate at pH 6, in contrast to published data which suggested pH 9 as the optimum value for ore processing. Using octyl hydroxamate, a rougher concentrate assaying 67 per cent Fe at 51 per cent recovery was obtained using four stage additions of 50 g/t at pH 6. For lower grade concentrates still meeting the chemical analysis for pigment grade micaceous hematite (minimum Fe assay 60 per cent) iron recoveries of 80 per cent were possible for stage additions of 50 g/t octyl hydroxamate in the pH range 6-8.

Jan 1, 1999

By Hancock RG, Dewar GJA

The mining and exploration industry is governed both directly and indirectly by a complex and constantly changing regulatory and legal system, yet few technical professionals realise the extent to.which they are affected and that they are personally liable for any breaches. These breaches may result in criminal or civil prosecution that could involve significant financial penalties (to the extent that all personal assets are at risk) and even imprisonment. Generally, a professional at risk should be able to mount a due diligence defence in order to avoid or mitigate these consequences. Mineral property and company owners, directors, managers and employees are at risk, as are consultants, contractors and suppliers of equipment or consumables. Whilst all are liable for their personal decisions to act (or failure to act) in managing operations or carrying out directions, as well as for the actions of others under their control, the focus here will be on the exposure of the consultant. Consultants are usually driven by an internal desire to perform to a high standard because of personal pride in their work and concern for their professional reputation. However, there are an increasing number of external requirements for them to be able to demonstrate, if necessary, that their actions were based upon reasonable grounds and that their work conformed to current best practice standards. If they cannot do so, they may face potential personal Liability.

Jan 1, 1995

Low tonnage quartz vein-hosted stibnite lodes are widely distributed in rocks of the Tasman Fold Belt System in eastern Queensland, with particular concentrations in the Hodgkinson - Broken River Fold Belt and to a lesser extent in the Gympie Province of the New England Fold Belt: Higher grade deposits have been worked intermittently on a small scale since 1873, resulting in the production of about 5500 tonnes of antimony ore/concentrate with an estimated grade of about 55% Sb. Future production of antimony may be as a by-product from deposits, currently being explored/mined for gold in the Hodgkinson/Mitchell River area and the Amanda Bel goldfield. Establishment of an antimony processing plant in Queensland using the Quelar Process would provide a more reliable market for small producers and could stimulate future exploration and production.

Jan 1, 1990

By Bastias J

The Ranger uranium mine has operated in the Kakadu region of the Northern Territory since 1979. The mine's water management system was designed to cater for the wet-dry monsoonal climate and to satisfy the recommendations of the Ranger Uranium Environmental Inquiry - Second Report, 1977 (The Fox Report) with respect to environment protection. The Fox Report advised that the aquatic ecosystem of the region must be protected and that the mine should collect all runoff from disturbed areas. Furthermore, the mine was to operate as a no-release system until release standards, based on the experience of several years of operation and on the results obtained from monitoring and scientific investigations, could be established. Monitoring and research data have now been collected for a decade. it is evident that lower-than-expected concentrations of chemical constituents are present in the runoff waters which are retained on site. Standards have been established for the release of these waters to the streams when in flood during the wet season. Mine water quality data and release standards are presented. It can be confidently concluded that controlled release will not cause detriment to the aquatic ecosystems of the Kakadu region. The Ranger operation has demonstrated that environmentally responsible management of mine waters is feasible for future mining ventures in the Kakadu region.

Jan 1, 1988

A laminar-flow furnace was used to study the combustion of four flotation concentrates (chalcopyrite, pyrite, galena, and sphalerite) in air at temperatures up to 1400¦C. A special- Iv developed two-colour pyrometer was used to measure the temperature of individual chalco- pvrite and pyrite particles as they underwent combustion. Chalcopyrite and pyrite ignited with very high rates of reaction at air tempera- tures above 480 and 600¦C respectively, forming molten products. Galena and sphalerite required temperatures in excess of 700 and 1200¦ respect- ively to attain equivalent rates of reaction. The high rates of reaction for galena and spha- lerite were caused by vaporization. Temperature measurements for chalcopyrite and pyrite are reported here, together with vaporization measurements for chalcopyrite, galena, and Sphalerito

Jan 1, 1980

Flotation of Composite Synthetic Particles

Sep 13, 2010

By Drain P, Dibdin T. R

THE completion of the Linda incline man and supply haft at the Mount Morgan Gold Mining Oompany's mine led to an investigation of the various safety gears in general use in mining shafts. One of these gears completely fulfilled the necessaryconditions. This paper endeavours to give a description of the man car and safety gears now operating in the before mentioned shaft, together with the main considerations leading to their design and sub equent adoption. Fig 1 diagramatically shows a longitudinal section of this shaft.

Jan 1, 1911

By Blair JR

The tunnel alignments investigated for the Gosford Regional Sewerage Scheme are located in the Terrigal Formation and are covered for most of their length by a thick blanket of soil and weathered rock. The following techniques were found to be most effective in geotechnical investigations for tunnelling in this area: air-photo interpretation, seismic surveys to pinpoint drilling targets, in-situ measurements of strength,deformation modulus and permeability in cored holes, and the construction of rock- mass models. Cross-hole seismic modulus measurements, surface resistivity soundings and electric well-logging techniques were found to have limited applicability due to adverse local conditions.

Jan 1, 1976

By R A. Pax, B Cornish

Increasing the throughput of the MMG Century operation by over 25% from past practice to preserve cash flow close to the end of life of mine has revealed new throughput and load dynamic instabilities in the SAG mill causing significant time averaged loss of production. A twelve microphone array around the SAG mill (Pax, 2014) using the non-contact acoustic measurement methodology (Pax, 2011, 2012) has been used to diagnose the new dynamics. Dynamic acoustic noise signal information allows discrimination of the behaviour of the steel balls and the rock. Determination of mill load, toe and shoulder angles, water holdup, and proxies for mill load are possible.The instability was diagnosed with the help of an abnormality in the liners/lifters of the SAG mill with one row of lifters having a slightly increased in-mill life compared to the rest. The steel shoulder angle is observed to be disturbed cyclically at a rate of precisely one revolution at low throughputs of 750 t/h. However, at throughputs closer to 1100 t/h, the cyclic signal disappears indicating additional dynamics to randomise the repetitive behaviour of the mill charge. The cyclic signal has been used to operate the SAG mill with improved stability at 1100 t/h by adjusting the feed water addition rate.This paper presents and discusses these results and proposes the suggested origin of the extra dynamics. A small consistent aberration of the lifters circumferentially provides a useful detector of stable mill operation and a novel sensor for the dynamics of the internal operation of a SAG mill.CITATION:Pax, R A and Cornish, B, 2015. A novel measurement for the internal operation of a semi-autogenous mill using acoustic sensors – a case study, in Proceedings MetPlant 2015, pp 120–128 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

Deposits of the Reefton Goldfield, West Coast, New Zealand, are hosted on N-NE striking, upright folds of the Greenland Group. High-grade quartz lodes are hosted on axial planar shears, typically have short strike lengths, and form shoots that pitch steeply on the hosting shears. Deposits within the field area of a detailed structural study share these characteristics. Field mapping and microstructural analysis have demonstrated that the Greenland Group was affected by a multideformational sequence. Gold mineralisation is hosted on shears axial planar to the F2 folds, but occurred during a subsequent deformation event (D4). Deformation during D4 resulted from N-NE directed shortening, near parallel to the trend of the F2 folds. This event produced F4 kink folds that were accommodated by layer parallel slip on S2 parallel shears, gold mineralisation during D4 being confined to the dilational hinges of F4 kink folds. The semi-brittle nature of D4 allowed the formation of stockwork veining and disseminated mineralisation within the F4 hinge zones. Most deposits within the goldfield are similar to those within the field area, and are interpreted to have been mineralised during D4. The two largest known deposits within the goldfield, however, are distinct. The Blackwater Deposit, striking parallel to the hosting folds, has a combined strike length of 1 km. The Globe-Progress Deposit is hosted on an E-W striking discordant shear in which a brittle zone of disseminated mineralisation encompasses high-grade quartz lodes. The characteristics that distiguish the Globe and Blackwater deposits may be due to formation before and after D4 respectively. Detailed field mapping in the vicinity of known deposits throughout the goldfield will further refine the relationships between the F2 folds, later deformations and the localisation of ore deposits. Additional mapping may also help constrain the position, orientation and extent of additional orebodies.

Jan 1, 2001

By G F. Brent, S Hawke, M Rothery, P Dare-Bryan

Mine-to-mill studies have previously demonstrated downstream productivity benefits from relatively modest increases in blast energy, or powder factor. These increases have up to now been limited by safety and environmental constraints, since excessive blast energy can result in flyrock, unacceptable vibration, airblast and wall damage.Here, a new blasting method that overcomes these constraints is presented. For the first time it is possible to employ powder factors that are several fold higher than conventional blasting. Independent modelling has shown that such powder factors can potentially increase mill throughput by 20 to 40 per cent. The economic implications are substantial, both in terms of increasing production in existing operations and in consideration of capital and plant requirements for greenfield sites. In addition, mill electricity and grinding media consumption and their associated costs and energy and emissions penalties can be reduced.This method represents a step-change in blasting practices. It involves a novel design utilising dual blast layers within a single blast event, all initiated with state-of-the art electronic blasting systems. The energies in the lower layer can be as high as five times the standard energies, providing for intense fragmentation of the ore. Results from blast models have been confirmed in field trials of the method.Open cut gold mining, in particular, stands to benefit from this method. As gold grades decline, milling costs and throughput increasingly become constraints on production that can be alleviated with this new method. Additionally, it opens possibilities for improved recovery. Blast modelling studies show that dilution of gold ore within the blast can be managed with the new method. Furthermore, it has been shown that vibration from the new method is actually lower than from conventional blasting, allowing the use of the technique in proximity to mine highwalls and other key infrastructure such as underground orepasses.It is concluded that this new method could substantially increase gold mine production and profitability while reducing overall energy consumption and associated emissions.CITATION:Brent, G F, Dare-Bryan, P, Hawke, S and Rothery, M, 2013. Ultra-high-intensity blasting - a new paradigm in mining, in Proceedings World Gold 2013 , pp 395-400 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

The paper looks at those factors which led the Latrobe Valley Community Forum to .focus on shortcomings of the consultative process. that existed around the 1980 period, and the limitations on the ability of the community of the Latrobe Valley to have input to the factors affecting their quality of life. Through a review of the Yallourn East Field Extension project it seeks to demonstrate the changes that have occurred and some of the shortcomings still existant in the consultation process.

Jan 1, 1992

Broken Hill South Limited's discovery of phosphate deposits in the northwest of Queensland in 1966 prompted intensive exploration which has proved phosphate rock in excess of 2,000 million tons at ten separate deposits. Systematic exploration for phosphate in Australia was initiated by the Company in 1964. Early in 1966, an investigation of oil wells in the Georgina Basin in the Northern Territory and Queensland revealed widespread anomalous phosphate in early Middle Cambrian Beetle Creek Formation and Thorntonia Lime- stone. Phosphorites recognised in oil wells in the southeastern part of the Basin, Queensland, led to the discovery of the Duchess deposits, Exploration of the Beetle Creek Formation since 1966 has disclosed nine other sizeable deposits north of Duchess around the eastern margin of the Basin. The Lady Annie and the adjoining Lady Jane deposits, by reason of their location, 160 miles south of the Gulf of Carpentaria, are expected to be the first to be brought into production. Beneficiation testing and engineering investigations commenced in 1967. Transport between the deposits and various port sites in the Gulf of Carpentaria has been extensively studied and a slurry pipeline as a means of transport to a deep water island port, is now being investigated.

Jan 1, 1971

The limitations of the conventional practices, and their effects, in prospecting for and in the evaluation of alluvial gold deposits are briefly reviewed. Geophysical prospecting methods have demonstrated their complementary role in the delineation of deposits by reducing the number of boreholes which are primarily of a 'probing' type. Larger diameter boreholes, although more expensive on a linear basis, are much cheaper on a volume recovered basis. The need to have sufficient volume as well as number of samples is stressed. Classical statistical methods are not appropriate for such deposits as there is sufficient structure, or spatial correlation, to require the application of geostatistics. Quite reliable semi-variograms, but not in all cases, of the spherical scheme have been obtained. Subsequent kriging has, to date, been confined to unworked deposits: retrospective estimates to compare to production have not therefore been produced. However, the technique shows promise but indicates a considerably greater borehole density (of the conventional diameter) may be necessary to produce confident estimates. Used in conjunction with larger diameter boreholes, a lesser borehole density may be sufficient, through radical reductions of the sampling error.

Jan 1, 1977

Several years and millions of dollars later, the mining and extractive industries have now started to receive and implement industry based standards aimed at achieving better performance and output from the employee. IFAP in conjunction with the mining and quarrying industry has developed a range of training courses aimed at achieving the benefits that can be gleaned from application of these standards. The establishment of a career path and appropriate training packages for personnel involved in the handling and use of explosives provides industry with a training system that previously did not exist. The opportunity to receive quality training based on industry standards and aimed at achieving industry goals will now enable the industry to optimise itÆs explosives applications.

Jan 1, 1999

Based on the idea to copy crystallisation and precipitation phenomena occurring in nature, a new technology was developed allowing the preparation of metastable, mineral forming solutions. If these solutions are brought into soil or rock formations, directed precipitation of slightly soluble minerals takes place. Immobilisation of dissolved heavy metals as well as overlaying of reactive mineral surfaces with insoluble minerals can be achieved. It is possible to prepare solutions leading to the formation of gypsum, BaSO4, CaCO3, Ca(OH)2, Al(OH)3 or Fe(OH)3. The successful large-scale application of BaSO4 forming solutions was demonstrated in the former uranium mine Koenigstein of Wismut GmbH, (Germany).

Jan 1, 2003

Citigold Corporation operates the Warrior gold mine at Charters Towers, northern Queensland, mining narrow quartz veins (0.1 to 2 m wide) in granodiorite by long hole open stoping on levels 15 m apart. Access is by decline and cross-cuts with on-ore development drives. The mineralisation comprises Palaeozoic mesothermal quartz veins containing gold, pyrite, sphalerite and galena, hosted by the Ordovician age Towers Hill Granite. The gold grain size is variable from 1 to 500 ¦m with 1 m face samples up to 800 ppm Au, and average run-of-mine grades of 10 to 14 ppm. Despite the spectacular gold tenor, little visible gold is present. Gold grades are highly variable presenting challenges in ore reserve estimation. Tonnages are discounted by 70 per cent to allow for the low payabilities (30 to 50 per cent) of the veins. Estimation techniques allow high confidence in overall global grade estimates but poor reliability on a local scale (25 m). Kriging ranges as low as 5 - 8 m means that obtaining a Proved Ore Reserve by diamond drilling is not economically feasible, and broad-scale mine planning decisions are made at the Inferred Mineral Resource stage and mine design work at the Probable Ore Reserve stage. Proved Ore Reserves can only be estimated after underground development has proceeded through the mineralised body with levels at 15 m vertical spacing sampled at 2 - 3 m intervals along the level. However, reconciliations between actual gold produced and earlier resource estimates produce workable results. A further three mines are scheduled to be developed underneath the city of Charters Towers.

Jan 1, 2008

This paper describes the MillMapper technology developed for condition monitoring of liners and other operational parameters in grinding mills used for mineral comminution, by presenting a case study of its application. MillMapper provides maintenance engineers, operations managers and process and plant metallurgists with quantitative, accurate and reliable condition monitoring data for informed decision making regarding the maintenance and metallurgical aspects of such mills. MillMapper uses calibrated laser scanners for the capture of three-dimensional surface representations inside a mill during a shutdown so as to determine shell, feed and discharge liner thickness at a resolution of several million data points, a procedure that nominally takes five minutes to complete. Once several data sets over time have been collected inside a mill, MillMapper can be used for liner wear, liner wear zone, liner weight, ball charge volume, ball charge weight and intelligent profile tracking over time. Liner tracking in combination with site defined reline and failure criteria and with throughput tonnage data is utilised for change out prediction of each separate liner segment type.

Jan 1, 2008

The Hill 50 Gold Mine is situated at Boogardie, 3 miles on a bearing of 295 degrees from; Mount Magnet township. Mount Magnet lies 300 miles north-north-east of Perth, Western Australia (Fig. 1).The older workings of the mine may be identified with those of Sirdar, Gold Mining Lease 696M The Sirdar had been worked before 1902 though no records remain, and irom 1903 to 1912 about a thousana tons at a grade of 6' 2 dwt. was extracted annually; by the end of 1918 6,225 oz. of gold had been obtained from the milling of 17,852 tons of ore. In view of these yields, and the length and width of the lode, this mine was early recognized as one of the most promising in the district. From 1919 to 1924 the ground,including G.M.L. 1282M, was held as Mt. Zion G.M.L. 1183M.The Hill 50 Gold Mine N.L. company took up the workings as Hill 50 G.M.L. 1282M in 1934 and have continued operations to the date of writing. To the end of 1956 the Hill 50 Gold Mine had yielded 982,106 tons of ore for a return of 448,'602 fine oz. of gold.The mine has been described by: J utson (1915), Feldtmann (1920), Johnson (1949), and Finucane (1953). Finucane (1953) details the mine structure to a depth of 414 ft. The author was able to examine the mine to a depth of 1305 ft. Detailed main level mapping to the 1060 level and a detailed surface examination have revealed aspects of the structure which were previously obscure.

Jan 1, 1960