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Gekko Systems Pty Ltd have developed the Python Underground Processing Plant for the concentration of gold and sulfide ores. The Python plant has an established flow sheet including fine crushing, screening, gravity separation and flotation which aims to concentrate the valuable minerals (gold/sulfides). The aim of the plant is to achieve high valuable recovery into a mass yield of 10 - 30 per cent to reduce the amount of material that is needed to be taken to downstream processing. This paper examines the test work protocol for testing an ore to assess its suitability for the Python flow sheet. This paper will discuss the test methods employed to determine crushing requirements, continuous gravity recovery and flotation performance and how the results relate to Python design for the comminution, gravity and flotation circuits. Results from past test work will be discussed.

Aug 1, 2010

By C Taylor, E Retz

Sequential Gaussian conditional simulation of wide-spaced exploration data has been completed in order to optimise a drilling grid at Fortescue’s Eliwana deposit. The aim of this drill grid is to improve the confidence in the Inferred Mineral Resource. A mineralised domain within the Joffre Member of the Brockman Iron Formation was selected to be tested as it makes up a large proportion of the Inferred Mineral Resource and is drilled at a reasonable spacing.One hundred realisations of Fe, SiO2 and Al2O3 grades were completed in the domain. Three realisations were selected for each analyte to represent the range of equiprobable values and a further realisation was selected to represent the truth data set. These realisations were used to flag theoretical drill holes on varying spacings and patterns. The theoretical drill holes were used to estimate into block models using ordinary kriging.These estimates were analysed and the accuracy and precision of each drill spacing was assessed. It was concluded that the greatest improvement in estimation results was noted at either a 100 m × 50 m or 50 m × 50 m spacing.CITATION:Taylor, C and Retz, E, 2015. How much do we need to drill?, in Proceedings Iron Ore 2015, pp 491–500 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

Future hard rock mining will gradually move towards complete mechanisation which lends itself to remote control and ultimately to robotic mining. This will require different technical inputs into mining engineering and one of these is in the area of rock'mechanics. Traditional hard rock mining has had little rock mechanics input. Problems arising from high stresses and poor ground conditions have in most cases be remedied after they occurred, in the worst case by abandoning a particular stope or area and starting elsewhere. In a fully mechanised remote or robotic mining situation the financial penalty for such an approach could be severe, as a major part of the production costs will be in the development and the equipment. It is therefore imperative that a complete rock mechanics feasibility study is undertaken before an area is set up for robot mining and that a continuous stability monitoring system is installed that will predict rock behaviour well in advance of mining, such that the necessary ground control measures can be implemented without impeding the continuity of mining. This system will utilise already existing instrumentation such as extensometers and stress cells, and possibly additional improved instrumentation which has to be developed for this particular Application.

Jan 1, 1986

Draglines have been a significant part of world open cut mining since the early part of the 20th century particularly for the removal of overburden in the strip mining of coal. Since the mid-1960s draglines have played a major part in the large strip mining coal developments of Queensland and New South Wales.There are now over 60 large draglines operating in Australia ranging in size from 23 to 103 cubic metres bucket capacity, with digging depths to 60 metres, dumping heights to 50 metres and dumping radii to 100 metres. The application of these draglines has progressed through the uncovering of coal in shallow, single seam operations to deep multi-seam operations requiring a greater dependence on pre-stripping activities ahead of the dragline to remove overburden not able to be efficiently handled by the dragline.

Jan 1, 1992

The development of Mount Isa Mines Limited power supply is traced through the history of the mine operations. As would be expected, growth of the power supply system follows closely the increase in mine output, although it will be seen that total kWh. produced per ton milled shows a considerable reduction in later years when the mine output showed a more rapid rate of increase. That this reduction is not more marked is possibly due to the increased community and Shire Council power usage per head of population.INTRODUCTIONThe geographical position of Mount lsa, far from any large regional power supply Authority, dictated the policy that the Company be responsible for the production and suppiy of all power required for the plant operation. The Company also, in November 1937, accepted responsibility for the supply of a part of the power requirements of the township of Mount Isa. The history of power supply to the Mine may be divided into several phases.1. The supply Of lighting and power during the first plant construction period 1929-1931.2. The construction of the first section of the Mines Power Station, comprising Nos. 1 and 2 turbo alternators and boilers.3. The addition of No. 3 turbo alternator and boiler.4. The addition of No. 4 turbo alternator and boiler.5. The addition of No. 5 boiler.6. The addition of a. 2 turbo blowers for air supply to the Copper Smelter converters; b. 1 turbo blower for air supply to the L.ead Smelter; c. 2 turbo compressors for compressed air supply to the Mine and surface plant.

Jan 1, 1961

The epithermal silver-gold Red Rock Deposit is hosted in the Late Permian inter- mediate to silicic composition Drake Volcanics of New England, N.S.W. This deposit represents one of the few low sulfur epithermal precious metal systems in eastern Australia, and differ! from epithermal models in that the hydrotherma: system which produced mineralization was active in a shallow water marine environment. The Red Rock Deposit has a resource of 180,000 tonnes of 66g/t Ag and 0.9 g/t Au, and a Ag:Au ratio of 70:1. Mineralization is largely associated with hydrothermal brecciation, and occurs as disseminations, vein stockworks, and struc- turally controlled lodes. Ore minerals comprise acanthite (argentite), electrum, native Ag, Ag- sulfosalts and base metal sulfides, Alteration minerals associated with ore are quartz, cal- cite, adularia, pyrite, illite, illite-mont- morillonite, chlorite and sphene (leucoxene). Illitic and propylitic alteration zones sur- round the hydrothermal breccia. Bulk rock analyses indicate that alteration is character- ized by the addition of Si, K, Fe, Mg and the loss of Na and Ca. Ore was deposited from a boiling fluid in a temperature range of 222- 295¦C, and of 0.5-7 wt. Z NaCl equivalent sal- inity. An upper hydrostatic depth limit of about 800 m is implied for the boiling fluid ii an open vein. Sulfur isotopes indicate a mag- matic sulfur source, and oxygen isotopes imply a predominantly marine ore fluid. Modern analogs of the submarine hydrothermal system that formed the Red Rock Deposit occur in the Taupo Zone, New Zealand, and southern Kyushu, Japan.

Jan 1, 1987

By Jowett A

To compare open circuit lead primary rougher results at Mount Isa Mines Ltd., eleven surveys were made over five weeks of plant operation with varying ore sources, including a specially hauled sample of 100% Black Star ore. Three of the surveys which represented extremes in performance were selected for sizing, cyclosizing and assaying for lead, zinc and iron. A comparison of the flotation kinetics has revealed the similarities (including common problems) and differences for the surveyed ores. The concepts of entrainment and collectorless flotability are used to aid interpretation of the kinetic data.

Jan 1, 1978

By Sakurai F

Akita Zinc Refinery of Mitsubishi Metal Corporation (MMC) started operation in 1953 with a capacity of 560 tons of electrolytic zinc per month. Its capacity has been expanded gradually and reached 8,100 tons per month in 1973. However, present production level is about 6,500 tons per month due to the depressed zinc market. In 1963, newly developed sulphate roasting was incorporated for residue treatment. Since 1973, electric power from Ohnuma geothermal power station of MMC has been supplied in addition to hydroelectric power from Komata power station of MMC. At present, about 40% of power is supplied from our company's power station and the rest is from the power company. Recent customers' demands for zinc prod- ucts include various kinds of shape, weight and chemical composition of galvanizing zinc alloy. It is necessary for zinc producer not only to meet the requirements of customers but also to enhance the value of zinc product in order to expand the market of zinc.

Jan 1, 1987

By D Connelly

Quartz deposits are common in nature but the presence of quartz suitable for yielding high purity quartz is exceedingly rare. This paper describes a test work study on producing high purity quartz (HPQ) product to meet the tight product specifications of greater than 99.97per cent, including four and even five nines, for uses including, lighting and fibre optics and modern-day high efficiency solar panels. Due to demand in renewable energy applications the market for high purity silica solar panels known for their increasing efficiency and durability is rapidly growing. Demand continues to rise for the use of high purity quartz in semiconductors, electronics, imaging and sensor markets. Microelectronic components are created by chemically fabricating wafers of semiconductors such as silicon to obtain the desired transport of electrical charge and control of the current. The production of silicon metal from high purity quartz has been designated a Strategic Mineral by the European Commission and by the US Department of Justice due to the growing significance of this metal in various industries. The subsequent processing of quartz is the key step to adding value and aiding technological advances. Overall, the high purity quartz market is a highly secretive, specialised market with increasing opportunities for stakeholders. The attempt to produce HPQ in this work was carried out using an Australian quartz ore following a typical HPQ process flow sheet. The unit processes included primary crushing, scrubbing, magnetic separation, flotation, acid leaching followed by hot chlorination. The results indicate that grinding of quartz requires specialist equipment due to the hardness and extreme abrasiveness of the ore leading to additional iron contamination in the ground ore. The critical impurities were aluminium, iron, sodium, potassium, lithium, titanium, zircon, calcium and magnesium. The chemical refining was found effective. The hot chlorination process needed to be done at 1200°C in a chlorine – hydrogen chloride gas atmosphere. The risk of any gas being released during this stage is very serious and only specialist companies should and can carry out this step. More recent studies reported many new options that appear to facilitate the production of HPQ with the requisite purities more easily, but costly equipment along with highly trained operators are required and hence unlikely to become available in standard metallurgical laboratories any time soon.

Sep 1, 2024

The Northland Peninsula of northern North Island, New Zealand contains a complex and diverse record of volcanism which reflects rapid tectonic changes during the late Cenozoic. The main volcanic associations observed on the peninsula are late Cretaceous- early oceanic crust obducted onto Northland at the end of the Oligocene, Miocene arc-type rocks and Pliocene-Quaternary intraplate basalts. This sucession of volcanic successions can be related to tectonic convergence developing into subduction and followed by a an environment of tectonic tension. While the volcanic activity is ultimately linked to specific tectonic regimes, because of rapid change magmatism was decoupled from the specific tectonic event. This decoupling of magmatism and tectonism appears to be a feature of the zones of plate interaction in the southwest Pacific region.

Jan 1, 1990

Recent mineral exploration successes in the Proterozoic rocks of the Mount Isa Inlier are unprecedented in the regionÆs history. This new era of discovery, particularly for æblindÆ deposits, owes its origin to perseverance and advances in geoscience and exploration techniques, notably geophysics. Prospective host rocks outcrop over more than 50 000 km2 of the Mount Isa Inlier and extend a further 100 000 km2 below cover. They contain major deposits of copper, lead, zinc, silver and phosphate (Georgina Basin) and significant deposits of gold, uranium and cobalt. The discovery in 1923 of silver, lead and zinc at Mount Isa established the regionÆs world-class mineral potential. Since 1990, major orebodies have been discovered at Cannington (silver-lead-zinc), Century (zinclead-silver), Ernest Henry and Osborne (copper-gold) and extensions to known deposits at Dugald River and George Fisher (zinc-lead-silver), and Esperanza (copper). This success is of global significance and reflects a prospectivity upgrade since widespread copper mineralisation was discovered and mined in the Cloncurry district a century ago.

Jan 1, 1998

Manganese ore has been mined from the Peak Hill Gold- field since 1948 and from the Pi'lbaraòGoldfield since 1954, and it is probable that some deposits- In and, near the Phillips River Goldfield will be mined at a future date', There are also several million tons of mariganiferous ;naterial which is too low in manganese. .co.ntent_ for . present requirements. The manganese deposits¦of Western Australia are mostly superficial. They hav' been formed during the Cainozoic Era by supergene enrichment ò6f Precambbrian: manganiferoius sediments, and by deposition from -solution on, or'in caves in, the Cain- ozoic land surface. The manganese in solution was derived from the weathering of Precambrian manganifer.ous s.edimexsts, None of the deposits are of hydrothermal origin, nor are they related to igneous rocks in any war, other than as ultimate source rocks. There is ho evidence-'t.o.:sugge,st that meta- morphism has been responsible for.the emplacement of any deposit. The tenor of the ore varies'aec'ording'to the quantity of gangue in the orebody and- also to the nature of the part- icular ore minerals. The main ore.mine.rals are the oxides pyrolusite and cryptomelane and the 'o'xide-silicate braunite. The main gangue minerals are hematite, limonite and quartz. The deposits of high grade oreò(-above.45 per cent Mn) range in size from 50 tons to many thousands of tons but most of them are in the 500-5,000-tons r .nge .

Jan 1, 1964

General Gold was discovered in quartz veins at Wiluna in 1896, and the first lode was discovered in 1904. Since 1896, some 2.5 million ounces of gold have been produced from the Wiluna area. The mining operations at Wiluna are 100 per cent owned by Wiluna Gold Pty Ltd, a wholly owned subsidiary of Wiluna Mines Ltd. Oxide and sulphide gold ore is extracted by conventional open pit mining techniques, and ran-of-mine ore is processed through two separate circuits. The oxide circuit has a capacity to treat 600 0(X) tonnes per annum and the sulphide circuit has a capacity to treat 400 (XX) tonnes per annum. Additional gold is won by dump leaching sub-grade oxidised ore and by retreating of primary ore flotation tailings from previous operations. Testwork carried out in 1990 indicated the viability of leaching dumps of run-of-mine oxide ore, and in June 1991 Signet Engineering of Perth, WA, was awarded an EPCM contract to construct a nominal 2.5 million tonne dump leach facility, for a total construction estimate of 51.75 million.

Jan 1, 1994

By J Ding, H J Peng, S B. Zhu, L Hou, J R. Zhang, S Y. Wu

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Numerous Fe-Cu-Au-rare earth element (REE) deposits have been identified within the Palaeoproterozoic Dongchuan Group of the Kangdian region of SW China. Geochronologic and geochemical data of the dolerite dykes and other volcanic rocks reveal extensional activity occurred about 1.7 Ga called ‘Kunyang Rifting’. The Kangdian region underwent variable degrees of extension, meaning that breakup in the central part of this region occurred earlier than in the north. Research on microphysiography, isotopic geochemistry and inclusions of the Yinachang typical Fe-Cu-Au-REE deposits suggest that the dominant mineralisation fluid is high-temperature, high-salinity magma fluid, containing alkalic components, volatile phase and Cu-Au. Metasomatism and mixing between this magmatic fluid and carbonaceous wall rock and meteoric water caused the precipitation of Fe, REEs and Cu-Au. A chalcopyrite Re-Os age from the Yinachang deposit obtained during this study is some 50–100 million years younger than the timing of emplacement of the deeply sourced Haizi and Dongchuan dolerites. The Yinachang deposit is a typical iron oxide-copper-gold (IOCG)-type deposit, and the presence of this and other deposits in the Kangdian region indicates that the region hosts an intraplate extension-related IOCG system within the western edge of the Yangtze Block, China.CITATION:Hou, L, Ding, J, Zhang, J R, Zhu, S B, Wu, S Y and Peng, H J, 2015. Proterozoic iron oxide-copper-gold mineralisation in the Kangdian Region, south-west Yangtze block, China – a case study on the Yinachang Fe-Cu-Au-rare earth element deposit , in Proceedings PACRIM 2015 Congress, pp 255–264 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By M Saghaeian, A H. Baladastian, A Dehghani Ahmadabadi, V Sheikhzadeh, R Hejazi

This research was done to reduce silica from mixed hematite concentrate of Barfkar Iron Ore Sample and increase Fe grade using reverse flotation method (Depressing Hematite and floating Silica). The used sample in the reverse flotation tests was a mixture containing two types of hematite concentrates (Spiral cleaner concentrate and Slon-VPHGMS cleaner concentrate) with the percentage of 16 per cent and 84 per cent, respectively. Fe grade of two samples was 59.31 per cent and 57.52 per cent and SiO2 grade was 5.83 per cent and 6.71 per cent, respectively. After mixing, the Fe and SiO2 grade of the mixed sample was measured at 58.10 per cent and 6.20 per cent. For flotation tests, effect of variable operational parameters including feed size distribution (d80 = 130 microns and d80 = 53 microns), pulp solidity (25 per cent and 30 per cent w/w), pH (9.70, 10.20 and 11), Sodium silicate as a dispersant (500, 1000 and 2000 g/ton), Starch as a depressant (500, 1000, 2000 and 3000 g/ton) and EDA as a collector (180, 300, 400 and 500 g/ton) were investigated. For evaluating the influence of Sodium silicate and Starch dosage, initial flotation tests were performed on the main sample (d80 = 130 microns). These two parameters had no significant effects on the yield, Fe, and SiO2 grade of flotation concentrate based on test results. In the next step, screen analysis was carried out on the main sample for mineralogical studies. Accordingly, the suitable size distribution for releasing Fe and SiO2 particles was smaller than 53 microns. Therefore, the sample was crushed until d80 = 53 microns. Then, supplementary tests were performed on the crushed sample for studying the pH range, pulp solidity, and EDA collector dosage. After doing silica removal flotation tests based on the designed pattern and comparison of the results, the conditions consisting of size distribution d80 = 53 microns, pulp solidity 25 per cent, pH 10.20, Sodium silicate 1000 g/ton, Starch 1000 g/ton, and EDA 500 g/ton was selected as optimum values. In the last test, Fe and SiO2 grade was measured at 60.00 per cent and 3.93 per cent, respectively, and Fe recovery was obtained at 74.93 per cent.

Aug 24, 2022

Mining projects draw together stakeholders with various degrees of experience in managing and assessing financial risk. When this risk is not fully appreciated or quantified, the potential for making decisions not suited to investor requirements is significantly increased. A feasibility study provides key information on project development potential, requiring detailed technical investigations with thorough financial analysis. Centaur Mining and Exploration (CME) owned and operated Cawse Nickel Operations (CNO), one of three Australian projects to develop and process vast amounts of near surface nickel resources. A technical ædue-diligenceÆ and æbankable feasibility studyÆ confirmed the large resource base, newly applied yet tested technology and relatively low unit costs would produce nickel in the lower half of industry operating costs. A number of production variables including capital requirements, delayed start-up, nickel grade, processing, maintenance and product output were outside the feasibility estimate. This was combined with exchange rate fluctuations and lower Ni prices. The inability to generate adequate cash flow and service debt repayments ultimately led to receivership and liquidation of all assets. Following the sale of CentaurÆs gold and nickel divisions, $A 784 million remained outstanding to creditors. This paper aims to define key issues leading to CNOÆs collapse by reviewing feasibility parameters, valuation methodology and project development. Some methods of assessing project viability are discussed with the aim of increasing stakeholder risk awareness.

Jan 1, 2003

By Smith DM Jr

Silver deposits, in which silver forms at least fifty percent of the value of the ore, are abundant and large on the east side of the Pacific and are absent in the western Pacific. To determine if this uneven distribution is related to features of consuming plate tectonic boundaries which dominate the metallogeny of the Pacific Rim, the variation of Ag/Au in porphyry copper deposits was used to estimate the relative silver content of magma generated in subduction zones. Porphyry copper provinces with high Ag/Au occur in regions of the eastern Pacific where silver deposits are abundant, suggesting that the distribution of silver deposits is controlled by the relative abun- dance of silver in subducted ocean crust. Ocean crust being subducted in the eastern Pacific is mostly less than 50 million years old in contrast to most ocean crust in the western Pacific which is much older. Enrich- ment of silver in young ocean crust at spread- ing centers may reflect metallogenetic evolution over geologic time. Silver may be transported to the surface in volcanic rocks, and deposits are common where felsic varieties are abundant. The high ,solubility of silver in natural waters provides a natural storage mechanism for silver weath- ered from these rocks and ultimately circulated in near-surface hydrothermal systems where many silver deposits form. The regional distribution of silver deposits is not influenced by discoverability, vertical metal zoning, or regional tectonic style. The effect of igneous differentiation is unclear.

Jan 1, 1987

By M Castle, D Mendelawitz

The Marra Mamba iron ore in FortescueÆs Chichester Range project area occurs as a very flat dipping series of waste shale and iron ore beddings. These beddings vary from millimetre thickness to several metres. The ore material generally exhibits a moderate degree of competence when subjected to ultimate compressive strength (UCS) tests, normally failing at up to 60 Mpa. However, the strength of the beddings is markedly less when subjected to the tensile forces imposed by the cutting action of the surface miner. Two surface miners of differing age and sizes were tested over a period of almost three months. These machines produced a product that had not been subjected to dilution by blasting and of such a size that primary crushing is not required. The machines were able to cut all ferrous material presented to them with varying degrees of success. Material containing higher quantities of manganese were broken but caused catastrophic wearing of the picks. During the trial the volume of material produced by the two machines in various strength materials very closely matched the manufacturerÆs estimates. The major impact on costs per tonne related to the wear on bits, which in turn varied with the bit design and composition. Bit design and composition testing is continuing.

Jan 1, 2007

The Oregon-Idaho graben evolved after widespread Uwleiitic flood basalt volcanism associated with the arrival of the plume head of the Yellowstone hotspot beneath southeastern Oregon approximately 17-16 Ma. The north- to north- northeast-trending, 50 km-wide graben evolved between 15.5 and 10.5 Ma during east-west extension. The graben is part of a middle Miocene back-arc rift (1,100 km long) that includes the northern Nevada rift, the Baker and LaGrande grabens, and the Chief Joseph dike swarm of the Columbia River Basalt Group. The graben ceased to be a volcano- tectonic depression as the cross-cutting western Snake River plain began to evolve at approximately 10.5 Ma.

Jan 1, 1995

By P F. Knights

Mining companies are striving to achieve new levels of operational maturity and drive process improvement across the organisation in the face of unprecedented demand and limited supply of experienced human resources. Advanced analytics techniques can help overcome these fundamental challenges by applying data techniques not previously applied in mining. Today, decisions are usually locally optimised but do not achieve optimum capability for the value chain. Although more information is collected then ever before, it is difficult to link many sources of data together in the same place in real-time, for example plant history, maintenance, mine planning, logistics and engineering data. Consequently complex analysis of data is time consuming and requires specialist skills and knowledge, and is often neglected in the decision-making process. In the future, analytics will close the loop between analysing data and taking action. Analytics will become embedded in the business and routinely applied to improve decision making across the organisation, from senior management to operations and maintenance workers, but will not require specialist skills or be time consuming to analyse data. As analytics becomes embedded in the business process, decisions are supported by data (not on gut feel), and critically, data from many sources are integrated in real-time to improve the quality of decisions. Ultimately, predictive tools will help suggest, or even in some cases automate, courses of action. The main opportunities for analytics exist where the enterprise requires supporting technology to enable it to continue to evolve to higher level of maturity. This will be in the areas of asset management, rapid reconciliation and adaptive planning, and the inbound and outbound supply chains. Advanced analytics are also a key enabler for increasing the effectiveness and realising the true value of Remote Operations Centres to safely and efficiently support operations in remote locations with smaller workforces.

Jan 1, 2008