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THE object that the writer has mainly in view in presenting this paper is to draw the attention of those connected with the technical side of the industry to the unsatisfactory and by no means up-to-date methods employed in estimating the tin contents of an ore. At the same time, what is regarded, from the writer's personal experience, as a satisfactory and reliable method is explained in detail. It is a curious fact that for the last 25 years tin·assay methods have made little or no advance, while those now in general use ill connection with copper and lead ores can scarcely be compared with those then obtaining, so greatly have they been improved upon. Though it. is not altogether expected that the method herein advocated will at once meet with general approval, the writer hopes the resultant discussion may bring out points that have hitherto escaped detection.FIRE METHODSThe old Cornish method of smelting with anthracite is now obsolete. The cyanide assay, although unreliable, is still much used because of its simplicity. In the Malaya many buyers of tin ores use the cyanide assay, the smelting being carried out generally in a benzine furnace. It is essential that the smelting with cyanide be performed at a low temperature. Even then, impurities, such as Sb2S3 and...

Jan 1, 1912

By A Parbhakar-Fox, S C. Dominy

The prediction of acid and metalliferous drainage (AMD) from mine waste materials is critically important during all stages of the mine value chain. However, to determine such geoenvironmental characteristics static and kinetic testing of individual waste units must be performed on representative samples. The importance of sample selection cannot be underestimated; it is the single most critical aspect of any geoenvironmental investigation. Poor sampling techniques and inadequate sample selection will contribute to excessive variance, difficulties in interpretation and incorrect assessment. By undertaking mesotextural characterisation based on hyperspectral mineralogical data (with sulfur assay data if available), opportunities to improve sampling strategies are presented. Such data will inform the selection of samples for low-cost total sulfur, paste pH and geoenvironmental logging, which collectively will allow for accurate AMD forecasting and improved sampling practices to be achieved. Once sampled, robust quality assurance/quality control (QA/QC) protocols must be developed where the use of international certified reference standards become obligatory. This is currently not practised, resulting in inter-laboratory discrepancies when undertaking waste classification. Further improvements in geoenvironmental characterisation testing lies in the adoption of blended static testing protocols, whereby blends of waste materials can be efficiently tested so as to give an early forecast as to whether they will produce acidic or metal-laden drainage. Such information is integral in developing a waste schedule that will allow for a non-acid forming waste landform to be constructed right from the start of the operational phase. Ultimately, improvements in this discipline lie in technological innovations with regards to mineralogical characterisation, and by offering geoscience and minerals engineering students a competent education in the discipline. Collectively, this will empower a step-change in AMD prediction and waste handling, and will make the realisation of the United Nations Sustainable Development Goals a reality, rather than a dream.CITATION:Parbhakar-Fox, A and Dominy, S C, 2017. Sampling and blending in geoenvironmental campaigns – current practice and future opportunities, in Proceedings Eighth World Conference on Sampling and Blending , pp 45–54 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

The offshore Maui gas/condensate field was discovered by Shell BP and Todd on Services Limited in 1969. Subsequent appraisal drilling and negotiations with the Government led to a development agreement, æThe Maui White Paper' being concluded in 1973. Part of this agreement provided for the Government to take a 50 per cent shareholding in the field. The field is comprised of a double domed anticlinal structure containing two gas reservoirs at depths ranging from 2700 - 3000 m. Water depth is 110 m. The development plan called for two standalone steel platforms to be installed sequentially over a period of some years depending on gas demand. The first platform (MPA) was put in place in 1976 but difficulties were experienced with piling and drilling of the 12 (later increased to 14) wells did not start until 1978. First gas was piped ashore late in 1979.

Jan 1, 1994

By A G. Cuison, B V. Andam

Three well-known copper and gold deposits in northern Luzon, Philippines are located in the Mankayan Mineral District. These are the Lepanto Copper-Gold Deposit, the Far Southeast Porphyry Copper Deposit and the newly discovered Victoria Gold Deposit. The latter discovery led LCMC to shift from a predominantly copper mine to a gold mine. The pre-Eocene Lepanto basement andesite and the middle Miocene Balili volcaniclastic sequence underlie the Mankayan Mineral District. They are intruded by tonalitic to gabbroic Bagon Intrusive followed by diorite-quartz diorite intrusions. Diatreme emplacement of late Miocene-early Pliocene Imbanguila dacite pyroclastics and porphyries took place much later. Faults in the district mostly form a conjugate fracture pattern dominated by north and northwest trending shears, east-west trending extensional fractures and few north-south trending fissures. Victoria is an epithermal gold-base metal rich quartz vein deposit. The veins occur along tensional structures and it is common to observe crustiform and banded features among the sulphides and gangue minerals. It is an open space infilling type of mineralisation. The Victoria vein systems are divided into zones based on continuity. In each zone are major veins and associated spits. Dacite pyroclastics and porphyries predominantly host the major veins with a few narrow veins hosted by the Balili volcaniclastics and the Lepanto metavolcanics. The veins generally trend east-northeast with 75 - 80 dips towards the south. The longest vein can be traced fairly continuously for a horizontal distance of about 600 metres. The vertical persistence of major veins exposed on three level drives has a range of 150 metres and can reach as much as 400 metres based on drill hole intercepts. The vein widths vary from two to eight metres. Right lateral movements of either the NW or NE shear faults could have produced the east trending tensional fractures. The development of ore shoot patterns was recognised and has been helpful to the mining operations. Cymoid loops with defined pinch and swell features are noted both laterally and vertically. Complementing the structural pattern is the distribution of gold values along veins where lateral and vertical continuity is also observed. Gold is associated with quartz, sphalerite, galena and chalcopyrite. In relatively high gold zones, the abundant sulphides are sphalerite and galena. In relatively high copper zones, there is an abundance of chalcopyrite and tetrahedrite. Galena is always associated with sphalerite but less in abundance. Chalcopyrite occurs either as separate bands from or associated with sphalerite-galena. Chalcopyrite and tetrahedrite appears contemporaneous with sphalerite and galena but in some portions the former cuts the latter sulphides. The predominant gangue minerals are quartz, carbonates and gypsum. Rhodochrosite is the predominant carbonate gangue. Few sulphides are found in the carbonates. Gypsum (anhydrite) is found cross-cutting early mineralisation. It carries very few sulphides. The alteration halos around veins are relatively narrow. In an outward sequence, the silicic alteration occurs very near the veins, followed by sericitic-argillic alteration then to propylitic zones. It is also common to observe veins bounded by propylitic alteration. Preliminary paragenetic studies show apparent three stages of mineralisation, the early-quartz (-gold) stage followed by a carbonate stage and a late-gypsum stage. The abundance of base metals relatively decreases towards the gypsum stage. The Victoria gold deposit could have some genetic associations with the Lepanto Cu-Au deposit and probably indirectly with the FSE porphyry system. It is relatively apparent that the Victoria quartz-gold-base metal veins could have occurred similarly as the quartz-gold roots overprinting the Lepanto enargite mineralisation. This overprinting signifies the waning stages of the entire hydrothermal system.

Jan 1, 1999

By S Schwarz, D Alexander

The mining industry, and in fact the world, has undergone significant changes in the past five to ten years, ranging from the metals boom, the global financial crisis and the rise and fall of national economies, to name just a few. There has been a focus on sustainable development for projects and operations in the mining industry, mainly pushed onto the industry by communities, governments and other agencies. While sustainable development and operation is a worthy priority for mining operations, discussions with mining industry personnel (with a strong slant on the mineral processing perspective) have shown other issues have surpassed the typical issues of water resources, energy availability and the environment. These include staff turnover and skills shortages, extracting metal from more complex orebodies and the uptake of new step-change technology.A number of key operating mineral processing personnel were interviewed to determine their perspective on the current issues facing the mining industry. This paper details the findings of this survey and highlights some of the topics that have been identified as the top issues from a mineral processing perspective.CITATION:Schwarz, S and Alexander, D, 2012. Current issues in the mining industry - From the operational mineral processorÆs perspective, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 369-372 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

Commercialisation of Ni Heap Leaching at Murrin Murrin Operations

Sep 13, 2010

By P Storey, B Deans, T Lancaster

Straits completed its Feasibility study on the Whim Creek Copper Project in 1996. At this stage WCCP provided Straits with an open pit mine - heap leach - SX-EW copper project to follow on from its successful Girilambone Copper Operation (GCC). Since this time Straits has continued to review WCCP investigating a number of development and production scenarios. The development of Whim Creek, early 2004 and is on schedule to commence copper production in the final quarter of 2004. On current reserves Whim Creek will produce approximately 17 000 tonnes of copper cathode per annum for three to four years, at cash costs of The paper will cover a general description of the project, the project development and key design issues. Additional construction related issues associated with the complete relocation of the GCC plant to Whim Creek will be covered in the conference presentation.

Jan 1, 2004

Samples weighing 0·5 g are decomposed with hydrofluoric and other acids. Most elements are extracted ftom the acid, aqueous solution by Alamine 336 (tricaprylyl tertiary amine) and thorium is determined in an aliquot taken from the aqueous phase by means of its reaction with arsenazo III. Concentrations down to 4 p.p,m. may be determined at a rate of 100 samples per man-day of 8 hr.

Jan 1, 1971

The drill steel' sharpening shop, which stands adjacent to the Chaffers shaft, is built to the dimensions of 110 ft. 9 in. by 58 ft. wide, and is air conditioned in order to maintain reasonable working conditions during the summer months.Figure 1 is a plan of the shop, showing the disposition of the machines and equipment.LIST OF STEEL SHOP EQUIPMENTAir Conditioning Plant comprising:-1 Spray and Eliminator Type Air Cooler, 6' ft. x 7 ft. x 6 ft. with 80 fine sprays.1 No. 36 Keith type ER. Ball Bearing upcast multivane centrifugal fan.20,000 cfm. a in. WG. at 450 r.p.m.Fan motor, A.G.E. S.C. 10 h.p. 1,160 r.p.m.1 Water Pump. 2?!-3-in. Thompson Class G. Single Stage Centrifugal Pump.1 Pump Motor, A.G.E. S.C. 70 h.p. 1,160 r.p.m.Drill Steel Sharpening Equipment:-2 Holman Sharpening Machines, No. 11.1 Ingersoll Rand Sharpening Machine, No. 54.5 Ingersoll Rand Sharpening Machines, No. 50.2 Holman Hot Millers, Type DM. Double Spindle Machines.2 Morgan Hot Millers, Type 1.6 Reamers consisting of motors with Ingersoll Rand Chuck fitted to the shaft and carrying a reamer of i-in. square Ultra Capital Steel Motors, A.G.E. S.C. 1 h.p. 1,160 r.p.m.4 Double-sided Drill Sharpening Furnaces, oil fired with L.P. "Major" 2-in. non-rotary whirl type burners.Combustion Chamber, 2 ft. 4 in. x 6 in. x 12 in. Oil consumption, 3·3 to 3·8 gallons per hour.Furnace Lining, Standard Kyanite.Firebricks, 9 in. x 3 in. x 4 in.2 Moving Frame type double-sided tip hardening furnaces, oil fired using High Pressure Air reduced to 3 lb. per square inch.Combustion Chamber, 3 ft. 5 in. x 5 in. x 16 in.Burners, "Major" L.P. 2-in. non-rotary whirl type.Oil consumption, 3·3 to 3'8 gallons per hour.Furnace lining-bottom and sides, 60 only 9 in. x 3 in. x 4 in. Kyanite bricks.

Jan 1, 1941

By P Lindsay, J B. Hughes

Underground and opencast coal mining has been ongoing since 1896 on the Stockton Plateau, West Coast, New Zealand. Acid Rock Drainage (ARD) from historic and current mine workings has had an adverse environmental impact on the surrounding aquatic environment. The two main catchments affected by ARD are those of the Mangatini and St Patrick streams. These catchments flow into the Lower Ngakawau River, which holds high amenity value for the local community. Water quality targets set by Solid Energy for 2010 in the Ngakawau River include increased pH and clarity and a decrease in certain dissolved metals.   At-source ARD minimisation options are the first stage in mitigating the effects of mining acid forming rocks and reducing acid loads in the Mangatini and St Patrick stream catchments. ARD minimisation techniques reduce the quantity of acidity generated and thus reduces the treatment required. Treatment will be required for many years at Stockton due to current and historical acid formation. This paper looks at the treatment options that Solid Energy has been investigating including limestone leach beds, engineered wetlands, oxic limestone drains, and limestone dosing of catchment drainage. Particular focus is given to fine limestone dosing of the Mangatini stream and subsequent water quality improvements.

Jan 1, 2007

By W Ward, J Clegg, R Barnes, T Zhong

This paper provides an overview of methods for measuring tunnel deflection and construction’s effects on the surrounding environment during and post construction. It will also review illustrative case studies from within Australia and overseas that are most relevant to local construction conditions. Systems illustrated include; vibrating wire and fibre optic strain gauges, extensometers, load cells and piezometers. A novel system using radar interferometry which requires no contact to the structure will also be investigated.In Australia, the majority of tunnelling activity occurs in urban areas (or in the case of mining in rural area) with limited seismic risk. However, the unexpected movement of tunnels is an important factor for structural engineers to monitor. During construction, monitoring is focused on the performance of the tunnelling lining, the supports under real conditions and the effects on surrounding infrastructure. After construction, monitoring will determine the effect of live traffic loads and can also evaluate the durability and any degradation of the tunnel. The aging of some tunnels or the forces subjected by nearby major construction can directly lead to a decrease in structural stability and deformation.The conventional way of inspecting and monitoring those tunnel movements is to have engineers physically enter the tunnel and carry out the measurement work. Manual techniques include tunnel wall convergence checks or total station measurement. However the associated costs are high and measurement process is difficult as some tunnel areas are inaccessible and the data collection interval is limited by the speed of the operator.Automated sensor networks utilising extensometers, fibre optics sensors or strain gauges can be used on tunnel segments or surrounding buildings. Ground settlement measurement via boreholes or hydraulic monitoring points and remote measurement of dynamic deflection can be taken using microwave interferometry.CITATION:Ward, W, Barnes, R, Zhong, T and Clegg, J, 2014. Sensors and systems for the measurement of tunnel movements during and after construction, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 209–218 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

A New Technology of Applying SLon-2500 Magnetic Separator to Recover Iron Concentrate from Abandoned Tails

Sep 13, 2010

By J M. F Clout

In the iron ore industry significant emphasis is placed throughout the mining process on meeting chemical composition specifications for the export of fine ores, however, little has been published on the implications of ore chemical composition for iron ore sinter and pellet product quality. The ore bulk composition, together with the nature of the minerals in the fine ore both play a critical role in determining the type of high temperature bonding phases that form during sintering and pelletising. This paper uses the experimental determination of phase relations in model sinter and pellet systems such as Fe2O3-CaO-SiO2 (FCS) and Fe2O3-Al2O3-CaO-SiO2 (FACS) to examine the links between iron ore chemical composition and the temperatures used during sintering and pellet firing. The phase relations help to establish the critical thermal and compositional parameters that control the bonding phase chemistry which in turn influences the physical characteristics of the sinter or pellet matrix. Results show that lower Fe-grade (

Jan 1, 2002

By V A. Tsukerman

Prospects a new energy saving method for an efficient destruction of the sturdy and hard materials (rocks, ores, frozen soils, concrete blocks, etc) û the Electric Pulse Discharge (EPD) method of materials destruction for green processing in mining and processing of mineral raw materials are considered.The EPD-technologies give additional possibilities for solving ecological problems at the expense of increase of integrated approach of utilisation of minerals and industrial wastes. The scientific and technical level of executed development of EPD method is sufficient for organisation of design work to develop substantially new equipment. A number of plants have been developed and tested, including plants for processing raw material with minerals of jewels, plants for selection of mica from rocks, and plants for processing the merging of artificial mica.

Jan 1, 2002

By A M. Suchowerska, J P. Carter, J P. Hambleton

"In order to effectively predict the roof collapse of underground openings using continuum models, it is imperative that a realistic failure criterion is used to represent the rock mass. However, for coal mining operations, there is still uncertainty as to the appropriate failure criterion that should be used for the coal measure strata. This study compares stability numbers and collapse mechanisms for a rectangular underground opening predicted based on three commonly used failure criteria: the standard Mohr-Coulomb, Mohr-Coulomb with a tension cut-off and Hoek-Brown. Three methods of analysis are considered: an analytical upper bound method an upper and lower bound finite element formulation the displacement finite element method.The theoretical results are also compared with field measurements of subsidence above longwall coal mining. For the standard Mohr-Coulomb failure criterion, the friction angle governs the shape of the collapse mechanism, and the so-called critical width (the cavity width above which failures extend to the ground surface) ascertained from field observations in the New South Wales coalfields corresponds to a friction angle of approximately 30°. On the other hand, predictions obtained based on the Hoek-Brown failure criterion consistently overestimate the critical width. The results also show that tensile failure governs the stability of the cavity and shape of the collapse mechanism when a tension cut-off is introduced for the Mohr-Coulomb yield criterion.CITATION:Suchowerska, A M, Hambleton, J P and Carter, J P, 2014. Prediction of roof collapse for rectangular underground openings, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference, pp 367–374 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 5, 2014

By J Pan, Q H. Li, D Q. Zhu, C C. Yang, X Wang, Z Q. Guo

Al2O3 in natural iron ores generally occurs in goethite, kaolinite, gibbsite, hematite and iron carbonate. When the content of alumina in sinter increases from 1.11 per cent to 3.50 per cent, the reducibility of sinter decreases with the addition of four different types of alumina. When gibbsite and kaolinite are added, the low temperature reduction disintegration (RDI+3.15 mm) of sinter increases with the increase of Al2O3 content in the range of 1.5 per cent to 3.5 per cent. Furthermore, when adding pure reagent alumina, the increase of Al2O3 content in the range of 1.5 per cent to 3.0 per cent will increase the RDI+3.15 mm of sinter. The addition of ferric oxide–alumina spinel with the Al2O3 content in the range of 1.5 per cent to 2.5 per cent, also increases the RDI+ 3.15 mm of sinter. The influence difference is results from the change of the mineral composition and microstructure of sinter because of the occurrence state of Al2O3. Under the condition that Al2O3 content of sinter is 2 per cent, the porosity of sinter with kaolinite is 37.26 per cent, and the shape is irregular. When gibbsite and ferric oxide–alumina spinel are added, the porosity of sinter is about 16 per cent, and the pores are round. When pure reagent alumina is added, the porosity of sinter is 17.49 per cent, and the pores are regular and small. When kaolinite, gibbsite and ferric oxide–alumina spinel are added, platy calcium ferrite is mainly formed in the sinter, and some of it is columnar calcium ferrite. On the other hand, when pure reagent alumina is added, in addition to platy columnar calcium ferrite, acicular calcium ferrite is also formed in the sinter.

Nov 8, 2021

A Mechanistic Model of Batch Grinding in Ball Mills

Sep 13, 2010

By K S. Fisher, J D. Pease

The installation of the George Fisher flowsheet in the lead/zinc concentrator at Mount Isa Mines Limited has recently been completed. The George Fisher flowsheet involved moving flotation capacity from the lead circuit to the zinc circuit and changes in zinc circuitry, changes in the reagent regime and increased regrinding capacity, using IsaMills, to regrind some streams to 80 per cent passing seven microns. The project was highly successful, delivering a five per cent increase in zinc recovery within a fortnight of commissioning. The George Fisher flowsheet was developed over six years. Laboratory work built upon the knowledge gained from investigating and processing the Mount Isa and Hilton orebodies. The engineering design and construction for the brownfield expansion of the existing lead/zinc concentrator had significant involvement from the operational, maintenance and technical personnel. Experienced personnel were seconded from the concentrator to the design and construction groups to ensure smooth integration of the new flowsheet into the existing concentrator with minimum downtime, and maximising the reuse of existing equipment. The combination of thorough design, good project integration with operations, and a good commissioning plan allowed almost immediate delivery of project gains. The project was highly successful, the full design improvements were achieved within two weeks, allowing the focus to move to developing future improvements.

Jan 1, 2000

By M Hernan

Bendigo Mining Limited has established a modern underground gold mine and processing plant at Bendigo in central Victoria. The Bendigo goldfield produced around 22 000 000 oz of gold between 1851 and 1954. Approximately 4 000 000 oz were sourced from surface alluvial workings with the remaining 18 000 000 oz won from underground quartz reefs. The modern mine is accessed via the Swan Decline, which commences at the Kangaroo Flat site on the southern outskirts of Bendigo and progresses in a north easterly direction between the Deborah and Sheepshead anticlines, reaching a depth of almost 1000 m below the City of Bendigo. Development of this decline commenced in 1998. Since that time 20 km of underground development has been completed. Exploration drilling, on-reef development and bulk sampling carried out between 1999 and 2005 resulted in the estimation of a Probable Ore Reserve of 700 000 tonnes at 9.0 g/t gold for 207 000 oz of gold. These Ore Reserves were contained within four reefs located on the Deborah and Sheepshead anticlines. Reef mining commenced in late 2005 from the Shywolup and Greater Garrard reefs. Material mined was stockpiled on the surface in preparation for commissioning of the process plant which commenced in mid 2006. Mining and processing were carried out between August 2006 and May 2007 during which time 176 000 tonnes were processed at an average grade of 5.4 g/t gold to produce 26 735 oz of gold. Plant feed was sourced from four reefs. This paper discusses some of the issues which were encountered with the definition and mining of these geologically variable and nuggetty reefs. This paper covers exploration techniques, grade estimation, mine geological control, mining methods, geotechnical issues and reconciliations. It will also discuss some of the lessons learnt and how these will be applied to future Mineral Resource and Ore Reserve estimation, as well as underground operations.

Jan 1, 2008

Laboratory and pilot plant investigations aimed at recovering gold as an electroformed sheet from gold eluate and gold leach solutions and slurries are discussed. The electrolytic test work undertaken makes use of high surface area electrodes, in particular nickel-chrome foam metal and activated carbon, as well as ultrasonic activation. The process involves initial gold electrowinning (or adsorption onto activated carbon), followed by gold electroforming, both operations being carried out in a specially designed reactor. The pilot plant work mainly involved the treatment of gold eluate solutions from a South African gold mine containing 600 mg/L Au: some tests were also carried out on gold leach solutions containing 6 mg/L Au. In the former case, very efficient gold extraction onto the foam metal cathode was achieved using electrolysis combined with ultrasonics. The polarity of the gold-loaded cathode was then reversed and, using a replacement electroforming electrolyte, gold was electroformed in situ onto a polished stainless steel mandrel, from which gold sheet was subsequently removed. In the case of leach solutions, pilot plant tests confirmed laboratory findings that in the presence of calcium (resulting from the lime used during the leaching process) no electrowinning is possible. Laboratory tests showed, however, that when sodium (in the form of NaOH or Na2CO3) is added to the leach solution, electrowinning can indeed take place. Alternatively, if a special activated carbon electrode is used (without current), the non-ionic calcium aurocyanide complex is adsorbed on to the activated carbon. When a gold-loaded activated carbon electrode is made anodic in a gold electroforming electrolyte, gold electroforming is feasible, although the efficiency is very low. The possible implications of these developments for gold recovery are further examined.

Jan 1, 2007