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Metana Minerals commenced life in 1970 and graduated to a mining company in 1981 with the opening of a small alluvial tin-tantalite mine at Wodgina (W.A.) The present board of directors assumed control of the company in 1978 and established the exploration and development philosophies that have guided the company's expansion to its present status as an emerging diversified miner. An ability and willingness to raise equity capital when required has been a feature of the company. Company activities include exploration for gold, diamonds, heavy mineral sands, polymetallic (base and precious metals) deposits, strategic minerals, rare earths, oil and gas in a geographical distribution covering the entire Australian mainland Metana owns and/or operates four gold mines (Reedy, Mt Magnet, Youanmi and Howley) and at the time of writing is developing a fifth gold mine - its first underground mine - at Rothsay. In contrast to many similar or larger sized companies, Metana undertakes most activities itself rather than through the use of consultants or contractors. In-house services include: analytical and metallurgical laboratories, plant engineering design and construction, drilling and mining (earthmoving) Metana Minerals has established an enviable reputation for technical excellence and this expertise has placed the company in a sound position to continue its growth pattern into the future. This growth will be achieved through a combination of low cost and successful exploration and acquisition of suitable mines either directly or through corporate activity.

Jan 1, 1989

By M Furche, U Noell, C Grissemann, J A. Meima, T Graupner, A Romero-Baena

The mining residues at the abandoned copper mine site Pe±a de Hierro, located at the headwaters of the Rio Tinto, contribute substantially to the pollution of the river with high loads of Fe, As, Pb, Zn and Cu. The pH of the outflow ranges from 0.5 to 2.4 in the dry and wet season, respectively. One heap composed of alternating layers, which were deposited parallel to the slope, was investigated in detail. Unsorted blocky to fine materials including gossan material, pyritic volcanics, ashes from pyrite combustion and slate were observed here. The top of the heap has a gentle slope and a hill contouring channel-rip morphology. The initially rugged surface was smoothed by heavy rainfalls filling up the pores of the blocky material with fines. These fines are capable of storing the water for a prolonged time, providing an extended reaction time close to surface in a dry climate at extremely low pH conditions (one to four). All minerals, pyrite, mica, barite and even quartz (probably due to F released from dissolved mica) have been digested and silica gel precipitates have formed a stable and quasi impermeable 100 ¦m layer with very low porosity (<5 area per cent, estimated using scanning electron microscopy (SEM) imaging). The silica layer itself is covered by Fe-oxy-hydroxide (ie FeOOH) coating (10 ¦m) and seals a 1 - 5 mm thick stable hardpan. This hardpan covers the channels and part of the rips almost entirely, guiding the rainwater subhorizontally towards slopes and sinkholes. By geoelectrical measurements, a 3D-resistivity model of the internal structures and the bedrock relief underlying the heap was generated. Internal structures relate to lithological changes in a number of layers. Zones of low resistivity may be attributed to washed-in fines within the mega pore system, whilst zones of high resistivity close to the surface probably reflect the advanced stage of drying beneath aging hardpans. The water movement at the surface was investigated by an artificial precipitation experiment with monitoring of the subsequent changes in resistivities.

Jan 1, 2008

Experimental results are presented for the anode overvoltage as a function of current density for different alumina concentrations in an alumina reduction cell. Voltage changes due to the electrolyte resistance and also the decomposition voltage, have been evaluated as a function of alumina concentration and anode current density. From these values of voltage, changes in the total cell voltage have been derived for changes in alumina concentration for different anode current densities. The results show that for each operating current density there exists a discrete alumina concentration that defines a minimum reduction cell voltage. Discussion is made about potential savings in power consumption when the alumina concentration is controlled.INTRODUCTIONThe standard procedure in the aluminium industry when analysing the cell-voltage required for the Hall-Heroult process for reduction of alumina, is to subdivide the total voltage into the following components (e.g. Pearson, 1955; Maritell, 1960).1. ohmic drop through busbars and joints2. ohmic drop through cathode lining3. ohmic drop through anode4. ohmic drop through electrolyte5. overvoltage at anode6. electrolytic decomposition voltage.(Overvoltages ,at the cathode are of negligible magnitude at all practical current densities.)It is understandable that the voltages assigned for each factor invariably differ for different workers...

Jan 1, 1965

Urban development to the south of Sydney is approaching areas of current and proposed coal mining. Already some structures and residential areas are affected by mining subsidence.Subsidence resulting from either conventional pillar extraction methods or longwall mining has been monitored for 15 years to enable the characteristics of the surface deformation to be determined.The vertical and horizontal displacements of survey stations on the surface are monitored and the results arc used to calculate subsidence, changes in slope of the surface, curvatures along the subsidence profile, and the ensile and compressive strains. These features are in turn related to the underground extraction to give a description of surface subsidence and the development of subsidence with time.Subsidence investigations have been carried out over all or part of the workings of six collieries in the Southern Coalfield.Two case histories illustrate the procedure in the investigation of subsidence phenomena. The first example is the study of the subsidence over a series of longwall panels in one seam and the second is a study of subsidence over pillar extraction in two seams one above the other. From the results of the investigations the effects of panel widths on subsidence are determined.This and other information assists mine planning in areas where surface movement and deformation are important considerations.

Jan 1, 1980

By K Pery, J Leahy

Established metallurgical plants operate in a complex environment of interdependent drivers including technology change, operating and maintenance practice, evolving markets, HSEC requirements, statutory and plant requirements, personnel turnover, ore supply, and financial conditions, to name a few. A successful optimisation program should comprehend these factors and drive towards not only lower operating costs, but also higher rates of return for a given level of investment. Optimisation programs have the potential for very high rates of return on capital that Greenfield projects rarely have. This paper presents a robust strategy and methodology for plant optimisation initiatives as well as a case study of how it was implemented at the QNI Yabulu refinery in Queensland, Australia by an integrated team of researchers, engineers and operators. The methodology is premised on the fact that nobody knows the production asset as well as the current operating team. It covers the optimisation process from ideas generation, various stages of selection against the agreed criteria, development, including testwork, funding approval and implementation. It highlights the benefits in the use of integrated teams, the establishment of a sound project basis, and a diligent, phased approach.

Jan 1, 2004

By L Bartsch, M Kelahan, E Wingate, J-S David

The use of column flotation cells for recovery of phosphate is becoming more common practice in certain parts of the world (Brazil, Russia) where igneous phosphate ores are processed. Igneous phosphates are generally finer grained (< 200µm) than some of the traditional sedimentary phosphates (<400µm). Australian phosphate from the Georgina basin is sedimentary, but has a much finer grain size (typically < 106µm) than similar deposits in North Africa and the USA.In 2013, Arianne Phosphate completed a bankable feasibility study for the development of their igneous phosphate deposit at the Lac a Paul site in Quebec. Initially, lab test work and bench scale piloting indicated that using traditional mechanical flotation would be able to produce adequate concentrate grade and an economic level of recovery, but would necessitate the installation of a complex and operationally challenging flotation circuit. Later pilot plant testing using column cells resulted in a significant reduction in process complexity and facilitated the processing of the -20µm ore fraction which resulted in a 10% increase in P2O5 recovery and a 5% increase in concentrate grade %P2O5.Flotation column testing achieved a concentrate grade of 38.6% P2O5 at a P2O5 recovery of 90%. Using a mechanical flotation cell circuit, the concentrate grade was 36.4% P2O5 with a P2O5 recovery of only 78.8%. A noticeable feature of the testing was the simplicity of the column flotation circuit configuration (Rougher + 2 stages of cleaning + Cleaner Scavenger) compared to the mechanical flotation cell circuit (Rougher + Scavenger + 3 stages of cleaning).The financial benefit for this case study was estimated using a sales price of US$ 195/t FOB for a 38.6% P2O5 product, and an assumed cost of production of US$ 95/t, the netback price is calculated at US$100/t. For a daily milling rate of 55,000t/d, the improved flotation performance provides additional concentrate production of 1,203t/d. Using the netback price calculated above, this calculates to additional gross profit of US$ 120,260/d.Annualised, this equals US$ 40.7 million in additional revenue for a similar or reduced CAPEX.The use of column flotation on fine grained phosphate ore types often requires fine grinding and desliming to liberate the phosphate value, such as the Australian sedimentary phosphate ores. This may enable the development of deposits previously regarded as uneconomic.This paper discusses the potential benefits available to operators, and developers of new projects, for the use of column flotation cells in their metallurgical circuits as assessed by an engineering company.CITATION:Wingate, E, Kelahan, M, David, J-S and Bartsch, L, 2015. Does it make cent$ to use flotation columns for phosphate beneficiation?, in Proceedings MetPlant 2015, pp 353–365 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By Johnston W. H

MINING operations in the Waihi mine began, under the present proprietorship in the year 1889. Previous to this, and as far back as the year 1880, the presence of reefs in the Martha Hill had been known, and surface working on a small scale had beencarried out, without any great measure of success. The only method of treatment in use at this time was the old system of light stamps, amalgamating tables and berdans, and recovery by this method being low, little margin for profit was left, so thatthe property in these days was not considered of great importance and work on the area was only carried on spasmodically by different owners.On the transfer of the leases to the present company, calcining, dry crushing, and hot pan amalgamation was adopted as the method of treatment, and this system was continued till the more modern cyanide process was introduced and applied. As themethods of treatment and gold-saving became more efficient with the application of more modern and scientific processes, the importance and future prospects of the mine became more and more pronounced, and mining on a larger and more comprehensive scale was gradually established.As in the case of ore treatment, mining methods in the early stages were not as far adv.anced as the adopted practice of today, and numerous shafts, levels close together in vertical height.

Jan 1, 1912

Mineral deposits in New Zealand whose origin can be ascribed to primary magmatic segregations are associated with mafic-ultramafic complexes related to two orogenic episodes which took place during Palaeozoic and Mesozoic times. These mafic-ultramafic complexes are essentially of two types. One is ophiolitic and has podiform chromite mineralisation presumably formed below a spreading ridge. The other type occurs as intraplate layered intrusions in which Fe-Cu-Ni sulphides and Fe-Ti-V oxides have formed as a result of liquid immiscibility with the host magma, and have subsequently accumulated by gravity means. Generalised descriptions are given for some deposits in NW Nelson, Fiordland and Marlborough districts.

Jan 1, 1980

By Lyman G. J

Magnetic separator operation in the recovery of magnetite in heavy medium circuits was studied by conducting a series of tests on a full size wet drum magnetic separator.The significant operational variables were found to be feed pan clearance, squeeze pan clearance, dry magnetite feed rate and separator drum speed. With feed and squeeze pan clearances optimized for typical primary separator operation, magnetite loss and concentrate specific gravity were found to be related in a regular manner to dry magnetite feed rate at any drum speed.A two component model of magnetite loss is proposed, relating total magnetite loss to losses in the feed pan and squeeze pan zones. The experimental curves relating magnetite loss to dry magnetite feed rate at the various drum speeds are interpreted in terms of the two component model.The magnetite particle size distribution in the separator was also examined. The tailings magnetite was found to be finer than the feed magnetite only when the dry magnetite feed rate was low, or immediately following the introduction of a new charge of magnetite when the separator was fed at an intermediate dry magnetite feed rate.

Jan 1, 1983

By C N. Whata

While there is no specific obligation on the part of any applicant to consult directly with tangata whenua (people of the land), recent cases highlight the need to engage in active consultation in order to avoid serious objections and delay, particularly where a proposal may affect the matters referred to in section 6(e) (Waahi tapu/sacred places) and 7(a) (KaitiakitangaiGuardianship) of the RMA.   The Environment Court has shown some sympathy for tangata whenua where waahi tapu and other significant matters of cultural concern are at risk because of a proposed development. There are several practical steps that can be taken to minimise the potential for serious objection including: ò knowing who to contact and how to contact them; ò demonstrating empathy for the concerns of tangata whenua; ò engaging in proactive consultation, for example meeting at a time and a place that is suitable to tangata whenua, and a preparedness to meet the costs of tangata whenua etc; ò demonstrate an awareness of tangata whenua issues; being aware of the types of mechanisms that are available to remedy, avoid etc adverse effects on matters of concern to tangata whenua.

Jan 1, 1997

By G T. Kukla

A Seam deposit User oriented Mine Planning System (SUMPS) was developed by The Broken Hill Proprietary Company Limited (BHP) at its head office in Melbourne. It is one of the computer mine planning systems developed by the Corporate Data Processing (CDP) section of BHP. To date it has been employed in the feasibility study of four coal prospects for the BHP Group, including Gregory in central Queensland û Ham and Van Hoorn (1978). It was also used in detailed short term mine planning for Gregory. A recent application was in the feasibility study of Saxonvale, a multi seam coal deposit in New South Wales with seams up to 20 m thick. The other two applications of SUMPS were also on thick multi seam coal deposits. Development of programs for the underground subsection of SUMPS is continuing. SUMPS was developed and implemented on mini computers with graphics and plotting peripherals. The company's philosophy towards computing is one of centralized development and project planning, with transfer of hardware and software to site once the mine becomes operational. Support of the site's system continues from head office which is continually involved in development of SUMPS and issuing revision updates to sites. The users, as well as programmers, were mostly geologists and mining engineers. This helped to ensure rapid, successful implementation. The broad approach of this system was to use interactively the specialist skills and interpretative abilities of the user mining engineers and geologists with the data manipulation abilities of the computer. It is an integrated system which covers geological exploration, deposit modelling, mine planning and production scheduling. An important feature of the system is that the user has full interactive control over each function through a graphics terminal where applicable.

Jan 1, 1980

By Armstrong M

The Coal Mining Engineering Branch of the New South Wales (NSW) Department of Mineral Resources, in its continuing effort to improve coal recovery from underground coal mining operations, has undertaken a study of the mechanics of sub-surface deformation caused by caving of the extracted area behind retreating longwall faces. The strata movement was monitored by a multi-wire borehole instrumentation system consisting of mechanical anchors installed at different horizons in a borehole extending from the surface to the coal seam. The mechanical anchors were connected to the suspended weights on the surface by stainless steel multi-strand wires. The movement of these weights was monitored as the longwall face approached and retreated past the borehole. The anchors started subsiding as soon as the face retreated past the borehole and continued to subside until the subsidence levelled off when the face retreated 900 m past the borehole. The zone of major caving and bed separation extended to roughly 10 to 13 times the extracted seam thickness and high tensile strains developed inthis zone. The bulking factor of broken strata was less than 1.14 which indicated that the roof layers collapsed in big blocks. The goaf compaction was almost complete when the face retreat was 200 m. Low tensile strains prevailed in the strata overlying the zone of caving and bed separation.

Jan 1, 1986

Interest in the tantalum-niobium minerals has been greatly stimulated in Western Australia by the fact that these rare minerals occur at numerous localities in that State, and in the adjoining parts of the Northern Territory, sometimes in mineable concentrations, as at Wodgina and Greenbushes. A large proportion of the world's tantalum comes from these deposits. The late Dr. E. S. Simpson, in particular, made an extensive study of the chemistry and mineralogy of these minerals, and the following observations are based upon the examination of specimens which he and Mr. H. Bawley, Government Mineralogist of Western Australia, have submitted to me for examination from time to time. The fact that so many of the specimens have been analysed provides a unique opportunity for the interpretation of the phenomena observed in the polished sections.TANTALITE-COLUMBITE SERIESIt has long been considered, on the basis of crystallographic form, chemical analyses, and specific gravity measurements, that ferrotantalite (FeO. Taz05), manganotantalite (MnO. Taz05)' ferrocolumbite (FeO. Nbz0 5), and manganocolumbite (MnO. Nbz0 5 ) form a complete isomorphous solid solution series (Simpson, 1937) and this is confirmed by study of polished sections of these minerals, Pehrman (1929) examined a series of five analysed specimens with Nbz0 5 contents as follows:-

Jan 1, 1940

By M P. Simpson, J L. Mauk

The Golden Cross, low-sulfidation, epithermal deposit shows a number of features that are directly or indirectly related to boiling hydrothermal fluids. Occurrences of lattice calcite and their quartz pseudomorph equivalents in veins, and occurrences of adularia in veins and in the surrounding altered rocks in the vicinity of ore, are both direct evidence of deposition in the presence of boiling hydrothermal fluids. Loss of carbon dioxide causes calcite deposition (platy variety) near the level of first boiling, while adularia deposits due to the attendant pH increase along the cooling flow path. Indirect evidence of boiling include crustiform-colloform quartz banding, late massive calcite veins, clay-carbonate alteration in the shallow and peripheral parts of the ore zone, and the restricted vertical interval of precious metal mineralisation. The colloform quartz banding strongly resembles the banding in amorphous silica deposits found in geothermal surface pipes. This implies that fluids ascending the Empire Vein structure were saturated in amorphous silica. If so, then they must have undergone phase separation, which initiated at considerable depth (e.g. =1000 m) and very hot temperatures (e.g. =300¦C). On the basis of stable isotope data, late massive calcite veins appear to have deposited from CO2-rich steam-heated waters. Calcite deposited along heating paths as these waters descended into the upflow zone during late stage collapse of the hydrothermal plume. In active systems, such steam heated waters form by deep boiling. The high CO2 contents of these waters promote hydrolytic alteration and the formation of clay-carbonate alteration. Reaction path modelling using CHILLER and a deep, Broadlands-Ohaaki water as an analogue, shows that minerals deposit along boiling flow paths over discrete spatial intervals. Calcite and adularia deposit near the site of first boiling, followed by gold and then by amorphous silica. For deep boiling starting at 300¦C, these minerals deposit over a path length that exceeds 1000 m. The distribution of banded quartz and gold at Golden Cross are consistent with such a boiling model. However, the elevation of first boiling must have fluctuated over 500 m to account for the coincidence of lattice quartz (pseudomorphs of platy calcite) and adularia, crustiform-colloform silica and gold over distances of a few centimeters in veins. We deduce that a downward propagating boiling front and expansion of two-phase flashing in a flowing water column occurred during episodes of high vertical permeability and fluid flux in the Empire vein structure.

Jan 1, 2000

Australia is not capitalizing on the raw gems and precious minerals that it produces in abundance. In particular, there is an unrealised value for diamonds due to lack of processing after mining. Australia could enhance the value of its raw jewellery products by developing and integrated jewellery industry. For instance, initiation of a diamond industry would require training programmes to educate people in the requisite skills, such as diamond sorting, cleaving, sawing, bruting and polishing. Equally important would be the training of people in design jewellery, manufacturing, and appropriate diamond grading and sales techniques. Future technological advances in diamond processing will decide where the major diamond processing centres of the world will be. Australia, for a relatively small investment, could develop a highly productive diamond processing capacity using the new technology available. Australia's geographical position, and advanced banking and communication facilities provide the potential for this country to become a major trading centre for diamonds. KEYWORDS: Argyle Diamond Mine, Diamonds, Diamond Production, Diamond Sorting, Jewellery Industry

Jan 1, 1989

By G Veillette, B Parker, S Hart

This paper provides a history of the challenges that were experienced while treating both the clayey oxide gold ores and the supergene copper-gold ores at the Boddington Gold Mine during the period 1989 to 2001. However the bigger challenge was to find a process flow sheet that would allow the economic treatment of the large low-grade competent gold-copper resource that underlies the oxide and supergene gold resource. Metallurgical test work and engineering studies on this resource started in the mid 1990s and culminated in the approval in 2006 of the 35 Mtpa Boddington Expansion Project to treat this material. The process flow sheet provides the basis of an energy efficient comminution circuit that includes high pressure grinding rolls and a treatment circuit with gravity separation, flash and conventional flotation to produce a precious metal low-grade copper concentrate followed by cyanide leaching of the rougher-scavenger and cleaner tailings streams. The treatment circuit allows maximum removal of copper minerals prior to cyanide leaching and so provides an environmentally responsible tailings disposal circuit.

Jan 1, 2007

A Study on Main and Interaction Effects of Operating Variables of Column Flotation

Sep 13, 2010

By P G. Self, M D. Raven, R A. Eggleton

Investigation of an abandoned quarry near Rowland Flat in South Australia identified asbestiform antigorite as the fibrous serpentine mineral mined during the 1940s to 1978 for filler applications, not amphibole asbestos or chrysotile as reported in earlier investigations. Scanning and transmission electron microscopy (SEM and TEM) and selected area electron diffraction (SAED) of individual fibres were used to confirm the identification. Chrysotile is widely regarded as the only asbestos mineral in the serpentine group. Further work was done therefore, on the geology and mineralogy of the occurrence, and the health implications were reviewed. A zone of antigorite alteration, with associated talc, is traceable for 750 m along strike of recrystallised dolomitic siltstone within Woolshed Flat Shale of Neoproterozoic age. The antigorite formed, in part, by replacement of prismatic crystals of probable tremolitic amphibole. The deposit is proximal to the Williamstown Fault and the serpentine-talc alteration is possibly due to fluids expelled along the fault during late-stage deformation in the Early Palaeozoic Delamerian Orogeny. The antigorite comprises white to pale green bundles of lath-shaped fibres that occur either as randomly- arranged equant patches after amphibole or as cross-fibre veins, both intimately mixed with calcite. Highly fibrous product was mined from the weathered zone where calcite was leached during weathering. Gentle grinding releases fibres with a high aspect ratio (>10:1) that show a wide range of fibre thickness, including a significant proportion of fibres <0.25 ¦m width. Toxicological studies on fibrous antigorite from Poland and Italy indicate that the carcinogenic potential of this form of serpentine is similar to amphibole asbestos. X-ray diffraction (XRD) and fourier-transform infrared (FTIR) techniques readily distinguish antigorite from chrysotile. Determination of asbestiform habit and confirmation of antigorite mineralogy is most reliably done using electron microscopy, preferably with SAED capability.

Jan 1, 2008

The mineralogy and textures of a portion oC ore from the 25 level northern orebody, North mine, Broken Hill are described. This ore, in places, contains up to 70 per cent cubanite (CuFe2S3 ) which has crystallized directly with other sulphides and associated gangue minerals.Several breakdown reactions involving the cubanite are also considered.

Jan 1, 1969

The Calypso geothermal field, mapped by the R V Sonne (cruise SO-135) in 1998, includes four main sites, the Northern Vent Area (centred on 37¦ 36.7'S, 177¦ 06.2'E, area 1.5 km2), Central Vent Area (37¦ 39.4'S, 177¦ 05.2'E, 1 km2), Southern Vent Area (37¦ 41.7'S, 177¦ 06.0'E, 1 km2) and Mercury Vent Area (37¦ 41.3'S, 177¦ 07.3 'E, 0.5 km2). Hydrothermal activity at the vent sites is controlled by minor, sub-parallel NE-trending normal faults. Gas bubble trails (C02) and shimmering hot water vent from fractures and joints between large blocks of silicified volcaniclastics and in depressions in the sediments at the base of these outcrops. Measured maximum vent temperatures are between 180¦C and 201¦C. Venting fluids are at, or just below, boiling for water depths of 200 m. Rock samples recovered by dredge from the sites include massive anhydrite, clay-altered pumiceous ash, silicified volcaniclastic sediments and volcaniclastic breccias cemented by sulphur. Clay-altered samples, dominated by randomly interstratified illite-smectite and accessory chlorite, indicate formation environments of 70¦C to 90 ¦C. Native sulphur is abundant throughout the samples. Fine-grained (<1 mm) disseminated pyrite and vein pyrite occurs in the clay-altered pumiceous volcaniclastics and argillites. In the Southern and Mercury Vent Areas, fine-grained orpiment, realgar and cinnabar have deposited in the sandy matrix of volcaniclastic breccias. Amongst the cinnabar, small (<2 mm) beads of native Hg formed on the surface of several rocks following their recovery. These samples also contained abundant light hydrocarbons, which coat the rocks with an oily sheen.

Jan 1, 1999