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The first geological maps of parts of Australia were produced in the 1830s and 1840s, many being for purely practical purposes, such as indicating the occurrence of coal, iron and other essential materials. Mineral location maps were also first made about the same time.More systematic geological mapping commenced in the 1850s when large parts of New South Wales and Victoria were studied in government-sponsored surveys by geologists such as Samuel Stutchbury, Alfred Selwyn and Reverend William B. Clarke. Their work coincided with the opening up of most of the major goldfields of eastern Australia, which led to the establishment of Departments of Mines in the separate Colonies (later States within the Commonwealth of Australia).A few companies employed consultant geologists at this time, and the mapping by Frederick Odernheimer is particularly notable. Geological study of Australian ore-deposits and mineralisedareas was influenced by the continental European geological ideas of men such as Odernheimer as well as by those from England. Both geological and mineral maps were a feature of Colonialdisplays presented at major international exhibitions during the second half of the nineteenth century. The maps accompanied rock and mineral collections which showed the known and potential mineral wealth of the Colonies. Such displays raised interest in the potential for development amongst government officials, entrepreneurs and investors in Australia and abroad.By the 1880s most of the Colonies had produced basic geological maps, and several maps of the whole continent had been published. Although systematic mapping of the continent become a reality only in the 1950s, the nineteenth century geological and mineral mapping formed the basis for the development of the major coal, artesian water, and metalliferous mining regions of Australia.

Jan 1, 1990

Variety among deserts is nearly as great as among other climatic environments. Common to most deserts, and to areas downwind from them, is the dominance of aeolian transport of surface material, at least during some seasons of the year. The result is dilution of local surface materials with varying proportions of chemically uniform fine sand and silt, often imported by the wind from remote areas. Fortunately, desert pavement,.even though separated from bedrock by a meter or more of nearly pure loess, is simply a diluted reflection of nearby bedrock. Infiltration of loess through the surface debris and the rudimentary soil-forming processes in the desert usually preserve the integrity of the pavement. This pavement, or its "downstream" derivatives, provides a suitable sample for exploration geochemistry if proper care is taken to circumvent the aeolian dilution. The simplest and most commonly used method of circumventing the dilution is to use a coarse fraction of soils or stream sediments, discarding or retaining the finer fraction depending upon the magnitude of the dilution. Where the coarse surface debris is composed of rock chips representative of the bedrock sources, the method is successful. Under most circumstances the coarse fraction of the surface material will give a fair representation of gross lithology and will occasionally give an indication of mineral- ization. The major drawback to this approach is that selective weathering and erosion in the vicinity of mineral deposits often lead to the loss of ore minerals into the finer fraction, leaving a coarse residue enriched in feldspar and particularly in quartz; thus, the geochemical signature from a mineral deposit is effectively reduced or completely masked. The second most commonly used method to overcome aeolian dilution, and probably the most effective at present, is to use a heavy- mineral concentrate. This approach presupposes that the chemical signature sought resides in a heavy mineral. Fortunately, the arid weathering cycle is conducive to the formation of a wide variety of secondary ore

Jan 1, 1988

By D Genge, E Martin, T Goswami, M Rothery

Rio Tinto’s Hunter Valley Operations is a large open pit coalmine situated in the heart of the Hunter Valley in Australia. The Riverview West Pit has faced increasing production challenges in recent times due to decreasing dragline strike lengths and increasing environmental constraints on vibration, overpressure and fume generation. Conventional mining techniques would involve five to six production blasts per strip to recover multiple coal seams. Each blast event carries the risk of exceeding the strict environmental requirements. By working collaboratively with Orica, it was realised that the blasting method known as Stratablast™, in conjunction with advanced computer modelling techniques, could provide productivity gains whilst simultaneously providing more control over the environmental effects and the impact on nearby infrastructure.As a result of this change, the number of blasts per strip was reduced to one, with the implication that a great deal of care and forethought was needed to manage the increased challenge posed by multiple constraints in the proposed mining area. This innovative approach of combining throw and stand-up blasts allowed the extraction of all major coal seams in a single pass blast event. The blasts were initially designed with a large factor of safety to stay within environmental limits as they were over 1.1 km in strike length, with more than 800 holes and with a total charge weight of about 1000 t of bulk explosives. Furthermore, there were conflicting priorities around the desired blast outcomes. So far, 11 such blasts have been designed and successfully fired. After each blast, innovative design changes have been iteratively implemented to provide further control over environmental impacts, whilst continuing to improve productivity. As a result of these changes, blasts have progressively increased in complexity with the inclusion of features such as damage zones, mid-splitting, time gaps and different directions of firing. The consequence of this complexity is that the blast duration can be as long as 28 seconds to accommodate all components of the blast.This project has increased the productivity of the Riverview West Pit through blast design improvements and allowed the environmental impacts to be managed with far more control and predictability than would have been possible under a conventional blasting regime. There still remains room for further optimisation of mine productivity and this is being addressed through a process of continuous improvement.CITATION:Goswami, T, Martin, E, Rothery, M and Genge, D, 2015. A holistic approach to managing blast outcomes, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 645–654 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By D L. Head

Critical risk management (CRM) has become one of the latest safety buzz terms in mining. Everyone seems to be doing it, everyone seems to know about it, yet we are still having fatalities in our industry from well understood hazards such as mobile equipment amongst others.

May 5, 2022

By D C. Ford

The Argyle AK1 orebody was discovered in 1979 and subsequently found to be a large, economically viable reserve with high grade diamondiferous ore. Production began via an open pit operation at the end of 1985 and has continued for some 25 years to present day. This, however, will come to an end in the next few years with production moving to an underground operation via block-cave mining methods.A series of studies from 2001 - 2005 was carried out; diamond drilling commenced after approval in 2006, from an exploration drive to determine the likelihood of the current proposed block cave operation.In 2006, development of the block cave project began, in order to realise the part of the orebody below the extent of the open pit mining operation.Development of the block cave technique, comprising an undercut level beneath the target zone of the orebody with subsequent extraction level 15 - 20 m beneath, relies largely on a number of block-caving parameters (hydraulic radius, rock type, structure and orientation of stress and grade of the orebody). These all have an influence on cave ability and eventual profit of the operation. Evaluation of further potential for taking this orebody beyond the block cave phase with options such as sublevel-caving are being considered for the UG-2 portion of the resource/reserve. Diamond drilling for this work is currently under revise.The challenges faced in transitioning form the surface operations to the underground, comprising a changing workforce, converging development drives, underground aquifers, major excavations and transportation of ore via automation are intriguing.

Aug 22, 2011

By M Jara, R Nuñez

As the global interest in sustainable energy sources has increased, lithium has emerged as a vital resource, playing a crucial role in the transition towards a cleaner and more efficient economy, but with this comes important challenges, especially associated to health, safety, and environmental matters. So, it is imperative for the lithium industry to prioritise HSE measures to protect workers, environment and surrounding communities. Implementing robust safety protocols and technology helps ensure the sustainability of mining operations and contributes to the overall responsible development of the industry. In this work we present how the Chilean lithium mining industry becomes a safer and more compliant industry using digital transformation (Cochilco, 2018; Bradley et al, 2013; Cabello, 2022).

Apr 16, 2024

By I Gray

Other than being reasonably certain of the average vertical stress being lithostatic, there can be little certainty about stress in the ground. The stresses and strains in rock are a function of gravitational effects, external load, thermal changes, diagenesis and their mechanical properties including elastic, creep and post failure behaviours. It is highly desirable to measure stress where mining is going to take place, even if the virgin stress condition has already been changed by mining. The concept of some far field stress value that is more or less constant is usually invalid and can be dangerous to use in mine design. Measuring stress is not simple. The basic processes are broken into two categories, one where the rock will not fail around the borehole in which the stress is being measured and one where the rock has failed or will fail. Because of the complexity and cost in obtaining a single, precise stress measurement it is highly desirable to have some system to be able to obtain an idea of the uniformity, or otherwise of the stress situation between precise measurements. Table 1 shows the methods for measuring stress. The first five methods work on the basis of some fairly direct measurement of mechanical rock behaviour while the last three are attempts to get some idea of stress out of core long after it is removed from the host rock. While these latter methods appear to tick all the boxes for applicability there is a great deal of uncertainty in the results that they deliver. This paper reviews the methods for measuring stress and presents two new methods. These are a three dimensional overcore system to provide precise stress measurements in rocks that will not fail around the borehole and a core ovality system. The latter can be used to provide information on the stress difference orthogonal to the core. It is particularly useful because it can be used every metre of core length.

Nov 29, 2022

The weathering profile, in arid terrains, is commonly capped by different kinds of hardened crust, whose formation is related to recent or former climates. One may distinguish silcretes, calcretes and the ferruginous (or ferro-aluminous) laterites. the present keynote address mostly deals with the lateritic regolith and, moreover, the influence it has on mineral exploration. The lateritic regolith, also called "cuirasse", is a result of a massive accumulation of Fe (and/or Al) oxides on top of weathering profiles developed during former, probably seasonal humid, climatic episodes, and whose preservation depends on the characteristics of later climates. The total thickness of such weathering profiles commonly exceeds 50 m, with an almost complete substitution of the rock forming minerals by secondary minerals as kaolinite and Fe-Al oxi- hydroxides (hematite, goethite, boehmite, gibbsite). Such an alteration of the primary minerals assemblage is of course accompanied by significant changes of the chemical composition, as concerns major and trace elements. The latter are distributed amongst the main secondary mineral phases or trapped in some primary resistant minerals, but may also be leached, totally or partially. Gold is also affected by lateritic weathering, as shown for instance by morphoscopic and geochemical studies of gold grains collected in the different horizons of the profile, which indicates some dissolution followed by reprecipitation.

Jan 1, 1988

By D Cliff

"Recent underground coal mine incidents have again raised the issue of: under what circumstanceis it safe for personnel to re-enter the mine? Mine rescue guidelines make recommendations aboutthe limits in terms of the circumstances, lives at risk, no lives at risk and training exercises. Theseare based upon percentages of the upper and lower explosive limits. Many factors infl uencesett ing limits for safe re-entry. These include: the representativeness of the sampling location(s),the rapidity of gett ing an underground sample analysed and the rate of change of the atmospherebeing monitored. Value judgements based upon these parameters will then infl uence the sett ing ofa trigger point based upon per cent explosibility. This raises the question of how the percentage ofthe lower or upper explosive limit is established. It is easy to defi ne this when the sampling pointdata sit on the fresh air limit line. However - what value is used when the sample sits somewherein the body of an explosibility diagram? This paper explores the various options and illustratesvarious pitfalls and problems that are faced in making such a determination. These include howthe data are represented and the assumed knowledge of those doing the interpretation."

Jun 1, 2012

By Smith C. B

Major diamond pipes discovered in Western Australia in the late-1970s exhibited a number of unique features that not only resulted in Australia becoming the largest diamond producer in the world in volume terms by 1986 but also changed geological thinking on the primary occurrence of diamond. They were: - lamproite is an alternative primary diamond host to kimberlite. - the extremely high mean grade of the Argyle lamproite pipe at 5 ct per tonne. - the tectonic setting of the lamproite pipes in mobile zones mar- ginal to the Kimberley Craton in contrast to the traditional African setting within stable cratons. Diamond was one of the earliest economic minerals discovered in Australia but 128 years elapsed between its first recognition and the first Australian economic pipe discovery (Argyle). During that period some 200,000 ct of alluvial diamonds were mined in Australia (mostly in New South Wales), but such alluvial output is insignificant on the world scene where annual production today runs at 95 million ct of natural stones some 76010 of which comes from primary pipe sources such as Argyle which alone produces 30 million ct per annum. Of particular significance therefore is the geological nature of the primary diamond source rocks in Australia. The Argyle and Ellendale Pipes are lamproites, differing from kimberlite in their mineralogy and geochemistry, and characterised by the presence of typical lamproite minerals such as leucite, priderite, potassic richterite, and the abnormally high content of chemical elements incompatible with ultramafic rocks. But not yet widely appreciated is that many other Australian olivine-rich lampro- phyres also contain diamond. Such picritic alkaline rocks can

Jan 1, 1988

By M E. Watson

Minimising dilution and ore loss is an important part of ensuring profitability of a gold mining operation. White Foil open pit gold deposit is a low-grade deposit and therefore managing ore quality is a high priority. Ground movement through blasting can displace ore and waste boundaries up to 10 m from their in situ location and therefore requires stringent ore movement monitoring and adjustment. There are currently only two options for monitoring blast movement – utilising visual targets (commonly lengths of polypipe) but this has widely been replaced by electronic blast movement monitors (or BMM). Regardless of the technology used, the basic principle is to compare the pre- and post-blast locations of the targets to determine the movement of the rock mass during blasting, which is then used to determine the final location of ore and waste boundaries.The Blast Movement Technologies (BMT) BMM system has been used at White Foil since June 2014. The system has been effective and reliable during that time; however, the annual cost of using the BMM system is greater than other monitoring alternatives. As such, the open pit geology team conducted a study comparing the BMM system against the conventional polypipe technique. The objective was to quantify the profit and loss that would occur based on the ore block transformations from both methods. Eight blasts were selected where polypipes were installed in additional holes adjacent to the BMM monitoring holes. The resulting movement vectors from the respective methods were used to create post-blast ore blocks by transforming the in situ ore blocks. While polypipe is a cheaper alternative, the BMM system tracks ore and waste boundaries more effectively resulting in better quality control, enhanced ability to minimise dilution and ore loss thus maximising profit. For these eight blasts, it is calculated that the BMM system resulted in A$664 978 extra profit through a reduction of ore loss. The total cost of a yearly BMM package was recovered in the first two blasts of this study. The primary reason for the difference is that polypipe had a poor recovery rate of 32 per cent compared with 92 per cent for BMM at White Foil. Therefore, the data used to transform the ore blocks was less representative, resulting in inaccurate post-blast ore block boundaries when using polypipe.CITATION:Watson, M E, 2017. Blast movement monitors or polypipe? A study into cost-effective blast movement monitoring at White Foil gold mine, Western Australia, in Proceedings Tenth International Mining Geology Conference 2017, pp 433–440 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By S Mitchell

Jetcrete Australia Pty Ltd, shotcrete contractor took the initiative in 2008 to discontinue the use of ‘road registerable’ concrete trucks for all underground works in Australia and internationally.The rationale for this decision was basic, safety. Historically these vehicles have been and still are involved in far too many accidents; this obvious trend needs to be addressed by engineering out the root cause of the problem which in this case is suitability for purpose.Road registerable concrete trucks have been widely used for the delivery of concrete in Australian mines for many years prior to and after the inception of wet shotcrete as ‘in cycle’ ground support in underground excavations around 1992. With this inception came a wide interest in the shotcrete process and an influx of new shotcrete contractors, all using road registerable concrete trucks to deliver the large volumes of Shotcrete required for these services and in turn largely increasing the use of these vehicles underground. The road registerable concrete trucks were difficult to control and each trip underground required the operators to maintain good management of the inherent risks. We virtually had no reasonable alternative for the industry and could only encourage the operators to drive with soft controls such as, reducing overall speed to a maximum of 15 km per hour when declining, regardless of the road conditions, coming to a complete halt prior to turning into any sharp corners, remaining in the same gear both inclining and declining.

Mar 21, 2011

Since the early 1990s it has been evident that electricity demand has outstripped investment in generation and transmission. At the same time, concerns were being expressed about the risks associated with the run down of the Maui gas field. It is axiomatic that the necessary investments firstly require a stable and supportive regulatory and fiscal environment, and secondly that such investments have long lead times. A unwillingness by successive Governments to fund the necessary infrastructure, however, lead to the profound restructuring of the electricity with the ultimate objective of transferring the investment risk from Government to the private sector. Successive power crises since 1992 result from a failure to put in place a regulatory framework necessary to provide the environment to allow the private sector to make the needed investments within the necessary timeframe. The electricity sector has now stabilised to the extent that the regulatory risks associated with generation investment have been reduced. This does not mean that risk has been eliminated, however, and both economic and environmental issues will continue to constrain investment in some power proposals particularly those in the South Island and especially any South Island coal or gas thermal proposal. This is firstly because of several very simple economic issues:  1. while the South Island may have significant coal resources it lacks a significant electricity market; 2. except for a six to ten week period in a dry year, low cost hydro will price any large-scale South Island thermal out of the market which will restrict any large scale thermal station to a dry year and/or peaking load; 3. except for a six to ten week period in a dry year, export capacity on the HVDC link to the North Island is constrained to around 964 MWe (and 482 MWe from North to South in dry years); and 4. construction of any new thermal plant in the northern half of the North Island will price any South Island thermal station out of the market. There are also significant environmental issues associated with the establishment of a large scale thermally based power station in the South Island. Because the South Island lacks any large scale economically proven gas reserves, the environmental constraints considered are those associated with coal production. A coal mine dedicated to power generation will have significant on-site impacts associated, in particular those associated with disposal of opencast overburden and visual impacts. These will, however, be partially offset by the relative remoteness of such sites to population centres. What cannot be offset, however, is the off-site impacts, in particular, CO2, SOx and NOx emissions, water disposal and acid mine drainage.

Jan 1, 2003

By C Jones

Ridgeway Deeps is a block cave (BC) located down dip of the operating Ridgeway sublevel cave (SLC) mine. The BC is located approximately 210 m vertically below the lowest SLC level and approximately 1100 m below surface. Due to the mine layout containing a number of common pieces of key infrastructure the activities of both were interlinked.When investigating project construction options for the BC, a number of potential risks were identified including a conflict of priorities between operational and project deliverables and the varying safety and work methods between an owner mining approach in the SLC and a potential contractor workforce in the BC. This led to a review of the construction philosophy and the opportunity to utilise the existing SLC workforce as the basis of all activities in the mine. It was identified that a number of synergies existed with the current SLC operators and mine supervision including common work practices and the opportunity to build on the unique SLC skills of the operators and supervisors which could then be used at other Newcrest caving mines.With the commitment to this philosophy of building on the existing SLC crews and supervision the number of employees reporting through the superintendent underground operations grew from 95 to 245. This increase led to a restructuring of the reporting and work requirements of the superintendent, foremen and shift bosses. In order for the foreman and shift bosses to focus on running the larger crew numbers for the full 12 hour shift the mine superintendent became a pseudo human resources manager taking over all non-mine focused activities including overtime allocation and work and behavioural performance management. In simple terms, ensuring there were competent bums on seats when and where required. As the additional workers were recruited to top up the existing employee numbers, their employment history was used to place them in the most suitable roles. For example, those with building industry experience were placed on the civil construction crews and those with a farming background were used as truck drivers, nippers or on the service crews. To cope with the increased number of new starters a number of key personnel were seconded from the crews into the training group to act as on shift trainers. This initially caused a reduction in mine performance as the main operators were reassigned but it proved a valid move as the time for new operators to reach acceptable levels was significantly reduced with safe operating standards being maintained. This paper discusses how the Ridgeway Deeps Project was delivered on time and under budget whilst at the same time retaining its position globally as an operation to be benchmarked against.

Mar 21, 2011

By J Miedecke

A metalliferous mine has operated at Storys Creek from the 1890s to 1979. Storys Creek drains from a pristine catchment and National Park and remains as the most degraded stream from historic mining in north-eastern Tasmania. It has been the subject of public concern since the closure, particularly at times of high rainfall such as existed in 1985 and 1986. The mine is located on the banks of the creek, which flows into a major river, the South Esk River, which is one of TasmaniaÆs largest rivers and important for recreational fishing and water supplies. For much of the life of the of the operations tailings were directly discharged into the creek, and in latter years stockpiled or very close to it. Little rehabilitation was carried out at mine closure. The result was erosion and subsequent deposition on the banks of the creek downstream. Direct emissions of adit water and the consequential emission of contaminated ground water to the creek continue to affect water quality. Contaminant loads discharging from the mine and tailings comprise 70% of the metal load in the catchment and are by far the largest single source. Acidity data suggested that the introduction of systems to introduce alkalinity could be effective in ameliorating the residual acid drainage impacts in the Storys Creek catchment. After a period of investigations and trials which proved their effectiveness, treatments adopted have included the following: relocation of tailings to a constructed and clay capped disposal area and rehabilitation of tailings area; crushed limestone addition to stream flows; crushed limestone addition to creek banks and exposed tailings; sealing of a drainage Adit; and construction of an anoxic drain to generate alkalinity to surface waters draining to old mine workings. These innovative treatments have resulted in a marked improvement in water quality draining from the area. The anoxic drain is believed to be one of the few, if any, which has been constructed to have generated high levels of alkalinity from clean waters and offers a solution to the clogging problems experienced in such drains in the past. Similarly, the use of crushed limestone in an active stream has proved effective in buffering acid drainage and removing metals from solution.

Jan 1, 2003

By M Zoorabadi, B Hebblewhite, S Saydam, W Timms

Based on the cubic law, the hydraulic aperture of rock discontinuities has the most significant effect on the hydraulic conductivity of jointed rocks. The hydraulic aperture of rock discontinuities is a stress-dependant parameter and reduces with increasing applied stress. Furthermore, the rock stress increases with increasing depth. Therefore, hydraulic aperture is a depth-dependant parameter. In this paper, new empirical equations are introduced to calculate the hydraulic aperture of rock discontinuities at different depths. These equations were developed on the basis of back analysis of compiled packer tests from different actual cases. They provide the capability to calculate range of variation and average hydraulic aperture when the orientation of discontinuity and field stress tensor are given. Furthermore, it is possible to calculate the hydraulic aperture of rock discontinuities when its value is given for another depth. A hydraulic aperture of 7.7?µm was calculated by this method, comparing well with a reported site value of 8.3?µm for rock discontinuities at the Stripa mine project at a depth of 385?m. These new equations can be used by analytical or numerical methods to estimate the hydraulic conductivity of jointed rocks.CITATION:Zoorabadi, M, Saydam, S, Timms, W and Hebblewhite, B, 2014. New empirical equations to estimate the hydraulic aperture of rock discontinuities at different depths, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 375–380 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By Subrahmanyam T. V, Rao V. D

GOLD, the most important and highly coveted valuable metal, is being sought and exploited in almost all the geological environ- ments by the developed, developing and underdeveloped coun- tries of the world. Brazil, one of the five largest countries of the world, has similar geological and lithological environments as of Africa, Australia and Canada and also produces this noble metal. With the recent gold rush in Serra Pelada Hill in Para State of Brazil and the consequent migration of a large number of enter- prises to the Amazon region in search of geological conditions similar to that of Serra Pelada, the status of Brazil in gold produc- tion has been considerably elevated to be among the first five of the world. The principal geological environments or the lithologies where gold can be explored are the greenstone belts, banded iron for- mations, quartz lodes and placers; and the tectonic controls like shear zones in these horizons, or the tectonic relics or the annular- structures that limit the quartz vein systems in felsic as well as volcanogenic systems and epithermal models. The greenstone, BIF associations are present in all the Archean-Proterozoic ter- rains in Central and Northern Brazil. The quartz boudins in Al rich schistose rocks and the weathered and chemically enriched

Jan 1, 1988

By L Dzinza, K C. Corin, M Tadie

The recycling of process water comes with increased electrolyte concentrations that affect water quality, which may in turn affect the flotation performance of valuable minerals (Hirajima et al, 2016). Electrolytes such as Ca2+, SO4 2- , Mg2+ and S2O3 2- have been surmised to have an impact on the action of flotation reagents such as collectors (Ikumapayi et al, 2012). Xanthate collectors are known to play a significant role in imparting hydrophobicity on mineral surfaces to enhance their flotation. The interaction between minerals and xanthates is well known to be electrochemical in nature. Such redox processes may be elucidated by electrochemical techniques. Since the mechanisms involving the interactions between electrolytes in process water with sulfide minerals and the subsequent adsorption kinetics of collectors are not well understood, this study therefore aims to provide fundamental knowledge to unpack the mechanisms involved when electrolytes interact with Platinum Group Minerals (PGMs) and how these interactions may affect xanthate adsorption. The interaction of sodium iso-butyl xanthate (SIBX) in the presence of electrolytes at increasing ionic strength was investigated by rest potential measurements, to explain the impact of electrolytes on the adsorption of SIBX on PGMs in the flotation process. Rest potential measurements for PdTe2 and PdS were conducted in an air saturated 0.05 M di-sodium tetraborate decahydrate solution, in the absence and presence of SIBX and electrolytes. It was found that the existence of sulfide and telluride on palladium affects the mechanisms in which electrolytes interact with Pd mineral surfaces. An increase in the ionic strength of Na2S2O3, CaCl2 and MgCl2, increased the interaction between the salts and PdS, thus decreasing the extent to which SIBX interacted with PdS. An increase in ionic strength for Na2S2O3 increased the interaction between Na2S2O3 and PdTe2 and therefore decreased the extent to which SIBX interacted with PdTe2. Other salts investigated in this study increased the rate of oxidation of PdTe2 with an increase in ionic strength thereby enhancing the interaction of SIBX and PdTe2. This study has shown that mineral type, electrolyte type and concentration all have an impact on the mechanisms that result in the adsorption of SIBX on PGMs.

Aug 24, 2022

By Kandemir H, Stafford G

The Croydon Gold Mine is located in northwest Queensland and is a joint venture between Central Coast Exploration N.L. and Pancontinental Mining Ltd. The mining operation commenced in 1987 and consists of satellite open pit mines feeding a central Carbon-In-Pulp gold Treatment Plant. The gold mineralisation is hosted by quartz veins within the Croydon Volcanic Group and the Esmeralda Granite, a cogenetic igneous suite of Middle Proterozoic age. The mineralisation comprises gold and silver with associated basemetals. The gold and silver electrum occurs as extremely fine free grains. The gold distribution is heterogenous occuring across the full vein width, or restricted to the footwall or hangingwall. The average mineral resource grade is 3.5 g/t. The deposits are all hard rock and mining is carried out by drill and blast technique. All mining activity is carried out by a mining contractor. Mining is by a selective mining method which entails the drilling, blasting and extraction of the hangingwall waste prior to orebody extraction.

Jan 1, 1989

It is a very great privilege for me to be able to address you tonight and I am deeply sensible of the honour which has been done me. I am equally sensible of the inadequacy of my training for the position of President of your Institute.May I say at once what a very great pleasure it is to have so many members from the mainland States visiting us here in Tasmania. We do hope that you will find pleasure and profit in your stay.Since the Annual Conference is always held in the vicinity of one or other of the great mining fields, it has become the practice for the Presidential address to review the history of the particular field and t(j) indicate its place in the economic structure of the country.I propose to follow this practice and to try and present to you a short picture of thÇ mineral industry as it has existed in Tasmania. None of the information is new it is available in diverse and remote geological reports and in publications such as Witham's Western Tasmania and the more recent Peaks of Lyell. The last composite approach was written twenty years ago by P. B. Nye and published as a Geological Survey Bulletin.I have enjoyed preparing this address because on occasion I find it refreshing to look back and see what was known and what was accomplished in the days when the going was a little tougher than it is now, and to speculate upon the reasons that drove men to do what they did. I shall therefore discuss the search for minerals in this State; the discoveries over the years; the elation with which the new fields are greeted; the disappointments attending some of them; the mines that have come and gone; and the...

Jan 1, 1958