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By I T. Ross

Sampling drawpoints in block cave mines has been a contentious issue for many years. Doubts have been expressed as to the validity of the process used at most mines. This paper outlines the sampling practice commonly in use, discusses the resulting issues associated with reconciliation and drawpoint closure decisions. The paper also looks to the future and highlights issues for some block cave mining operations currently planned to have in the order of one thousand active drawpoints. It is likely that these operations will require a new approach to drawpoint sampling. There are several potential technologies currently available although some appear to be better suited than others to replace the current approaches. CITATION:Ross, I T, 2012. Sampling in block cave mines, in Proceedings Sampling 2012 , pp 81-86 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By P Ramsaywok

The use of saline water for mineral beneficiation in arid regions is general practice and also the case with Exxaro Namakwa Sands, situated on the west coast of South Africa. Although it is ‘cost effective’ to use sea water for mineral beneficiation, downstream process separation efficiencies may be negatively affected. This is more specific to surface dependent separation techniques such as electrostatic and high tension (HT) separation. If minimal fresh water is available then, proper washing is often neglected. Salt crystals can form on particle surfaces during the drying process before electrostatic separation.This paper describes a study that has been conducted to determine the effect of upfront salt water processing on downstream electrostatic/HT separation. The study indicated that minor quantities of salt can cause the separation efficiency to decrease substantially.

Oct 5, 2011

By L Y. Yang, Z Wang

This work presents the fundamental properties of CITIC magnetite concentrate and its performance in pelletising and sintering. CITIC concentrate has been widely used in pelletising to produce pellets for blast furnaces. It is also used in sintering to benefit from its sintering performance. CITIC concentrate has excellent balling properties owing to its size distribution, particle surface properties, large specific surface area and balling index, leading to strong green pellets and product pellets. When used in sintering at appropriate levels, sinter bed permeability improves, productivity is increased while coke consumption reduces, and sinter strength improves.

Nov 8, 2021

By K J. McDonald

All commercially available zircon sands contain radioactivity sourcing from the decay of trace amounts of contained uranium (U) and thorium (Th). The fine particle size zircons of the Horsham area in the Murray Basin region of Victoria, Australia, contain significantly more (about twice) Th+U than those commercial zircon sands. The marketability of these fine-grained zircon sands is likely to rely on the removal of these radioactive impurities. CSIRO Minerals have been working for some time to develop processes for the removal of the radioactive impurities from zircon. It is generally agreed that it is quite impossible to leach U and Th from zircon, however, the Heat and Leach (HL) process, described in detail in Aral and McDonald (1999), reduces the radionuclide levels significantly. The identified (HL) process aims to leach uranium and thorium selectively from a decomposed zircon. The novelty of the process is that a large part of the leached product can be reconstituted to a low radiation zircon by a subsequent heat treatment. The HL process uses a flux mixture of sodium carbonate and calcium borate to decompose the zircon at relatively low temperatures (900 to 1150¦C) and a weak acid (0.5M HNO3; 80¦C/0.5 h; pulp density ten per cent) to leach the radionuclides selectively. The process leaves the major components (ZrO2 and SiO2) behind with little loss. The HL process for example lowers the U+Th content of a Murray Basin zircon from 1000 ppm to 400 ppm U+Th. Among the radionuclides more U progeny is removed than the Th series radionuclides. This is very significant as the radioactivity of U series is 2.5 times more that from the Th series. Therefore the reduction in the radioactivity level of zircon is more than the reduction in Th+U indicated by XRF analysis. A schematic flow sheet of the HL process is shown in Figure 1. Although the HL process successfully lowers the radionuclide levels in zircon sands, the final product contains significant amounts of sodium (up to 14 per cent Na2O) and small amounts of CaO. By comparison, the sodium content of the commercial zircon sands is in general 2O. Zircon is used mainly as an opacifier in tile glazing where the addition of ten to 15 per cent zircon to a translucent base glaze gives the sanitary white colour to the tile surface. Opacification is the result of the refractoriness of zircon particles at the glaze firing temperatures that is generally around 1050¦C.

Jan 1, 2001

By E Jak, J Chen, B Hogg, S Nikolic, S Nicol

The quantity of post-consumer ‘waste’ materials generated each year is rapidly increasing. These materials can contain significant quantities of critical metals and present an environmental challenge if landfilled. The ISACYCLE™ technology is a proven solution for the processing of these materials. In the ISACYCLE™ furnace, the post-consumer materials are processed to recover energy along with any contained critical metals, in the form of a base metal alloy or matte. In addition, a clean aggregate (slag) is generated, which has the potential to be used for a range of applications in the construction industry. This slag is commonly based on a fayalite slag but is modified to manage the complex feed. This paper will review the fayalite slag system and the theoretical modifications required for treating urban wastes. Slags from an ISACYCLE™ furnace processing urban wastes have been sampled and characterised. The chemistry of these samples will be reviewed and compared to the expected theoretical modifications required.

Jun 19, 2024

By D Connelly

High purity alumina (HPA) is a processed, premium non-metallurgical alumina product characterised by its purity level ie 99.99 per cent (4N) or 99.999 per cent (5N). The market price, application, and performance of HPA varies widely according to its degree of purity. High purity alumina is a form of aluminium oxide (Al2O3) with growing use in LED lighting and coating on the ceramic cathode separator sheets in lithium ion batteries. This paper describes a study on producing high purity alumina from feldspar to produce HPA and potash for use as a fertiliser. The project was positive for a number of reasons. High potassium extraction (>99 per cent) was achieved in the alkali leach using sodium hydroxide as the leaching agent and full dissolution of the alkali leach residue was achieved using hydrochloric and sulfuric acid. The potential to produce a high purity alumina product via a complex but promising emerging process was assessed. The potential to extract potassium as potassium sulfate to add value to the project was also demonstrated with the test work.

Sep 1, 2024

The first continuous pressure disk filter took up industrial-scale operation in Germany in 1976. This paper comments on major components of pressure filter facilities from the point of view of industrial-plant suppliers. For lack of time aspects of economy have not been commented upon. The paper elucidates a number of process-engineering inter-relations. It outlines important development trends from the angle of a machine-building company.

Jan 1, 1989

By H Wang, D Wang

Mine dust is the most serious occupation hazard in coalmines. And many coal workers suffer from pneumoconiosis because of long-term inhalation of respirable dust. Reducing the dust concentration of workplaces by effective technical means is an important way to prevent coal worker’s pneumoconiosis (CWP). In order to overcome deficiencies in existing dust control technology for underground mining, especially the disadvantage of water spray technology mounted on roadheaders or continuous miners, the authors developed an integrated dust suppression technology utilising foam for fully mechanised heading faces. This paper presents an overview of the principles, materials, equipment and application of this technology. Among these, a jet type foaming device and a green foaming agent were developed, which can realise the goal of efficient preparation of foam. In addition, an arc fan nozzle used for foam spraying was invented, which can effectively cover and enwrap the dust produced by the roadheader at the cutting point and achieve the goal of efficient utilisation of foam. This dust suppression application of the proposed foam technology was investigated on fully mechanised heading faces. The results show that the dust concentration was cut down significantly with a dust suppression efficiency of greater than 85 per cent, an increase of over 30 percentage points compared to the water spray system. This study demonstrates that this foam technology can play an important role in dust suppression on fully mechanised heading faces, which provides an important method to improve the working environment and protect coal workers’ health.CITATION:Wang, D and Wang, H, 2015. Technology of dust suppression by foam for fully mechanised heading face, in Proceedings The Australian Mine Ventilation Conference, pp 177–182 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By S Serp, M Duchateau, P Chevreux

Molten salt reactor (MSR) is a promising advanced reactor system aiming to the transmutation of minor actinides such as americium in order to reduce the inventory of ultimate nuclear waste. The fuel is a molten salt in which actinides are homogeneously dissolved in the liquid phase. A chloride salt may be retained for this concept, as it provides low melting point, high solubility of actinides, harder neutron spectrum. To avoid corrosion and precipitation issues, molten salt composition has to be carefully controlled with impurity content as low as possible. Obtaining pure actinide chlorides without contaminants such as oxide, oxychloride, hydroxide and water is still a challenge. To prepare actinide-bearing salt, the chlorination of actinides oxides was investigated in an unstirred reactor under flowing gas as solid-gas reaction. The carbochlorination of PuO2 were performed in the temperature range of 600 to 800°C with chlorine gas as a chlorinating agent and the presence of solid carbon. PuCl3 was successfully synthesised by this method and characterised by X-ray diffraction measurements but some impurities such as oxide phase remain inside the formed product. Refinements of anhydrous and hydrated PuCl3 phases by Le Bail method were also performed for crystalline materials definition. Conversion mainly depends on the chlorinating temperature and the contact between the oxide and the chlorinating agent. A conversion value of 70–80 per cent was achieved at 700°C from PuO2 with quite high specific surface area. The conversion rate was not improved with increasing the chlorination time. The volatilisation of Pu was observed during the carbochlorination experiments. To avoid a loss of Pu caused by sublimation, the chlorination temperature should be limited to 650°C despite that the conversion of PuO2 to PuCl3 was enhanced by increasing temperature. Both carbochlorination and hydrochlorination of AmO2 were also carried out leading to the formation of AmCl3. These first results suggest that americium oxide was chlorinated more readily than plutonium oxide. The purity of produced PuCl3 and AmCl3 still deserves further investigations.

Jun 19, 2024

By K Eglinton

The extractive industries response to community engagement due to social and political pressures in the 1980s and 1990s was the starting point of development leading to the modern function of corporate social responsibility.Challenged by communities who have greater access to information, demand greater transparency and responsibility of corporate organisations and who possess greater awareness of the communities they participate in, the mining sector faces another step change in how it approaches and integrates corporate social responsibility, transparency and engagement.Mining is seeking reserves of lower grades, in more sensitive environments and in countries with minimal transparency and governance. Not only are the locations changing but so to the stakeholders to engage with and issues to contend with. An increasingly savvy opposition, including not just the ‘green hippies’ but the Gen-Ys interested in the wider sustainability debate and Baby Boomers moving to life style environments, are now questioning mining’s behaviour and encroachment into ‘their space’. Issues including effect on lifestyle amenity, property value, energy efficiency, social provision; concepts such as ‘doing more with less’, participatory engagement, increasing transparency and balancing economic, environment, cultural and social aspects are becoming the norm.The traditional model of supporting local communities, communicating plans and providing employment, community investment and indigenous support programs is not enough. Our industry faces challenges on multiple fronts. It must now be able to address these from a personal/community perspective if it is to remain relevant within communities and play a role in addressing the global sustainability issues.This paper draws on corporate social responsibility trends, integrated functions and implementation approaches through the application of activities within Newmont operations across Asia Pacific.The approach presented works on the philosophy that communities do not necessarily have to like what we do, but should be able to identify and recognise the way in which we involve them in decision making, communicate our intentions and respond to issues.

Nov 22, 2011

By Canterford J. H, Sparrow G. J, Dyson N. F

Pressure leaching of a bulk flotation concentrate prepared from a complex Cu-Pb-Zn sulphide ore was carried out at 150 and 190¦C under 1050 kPa oxygen overpressure in 1 L and 4 L titanium autoclaves to extract zinc, and to obtain residues for smelting tests and leach liquors for purification and recovery of the zinc by electrowinning. Dissolution of 95% of the zinc was achieved at both temperatures. Copper and iron dissolution and the degree of oxidation of the sulphide sulphur to elemental sulphur or sulphate depended on the temperature of the leach. At 190¦C, a jarosite (a basic iron sulphate) was the major iron-containing material in a residue that contained 17% total sulphur. Its formation was associated with dissolution of 18% of the iron. At 150¦C, oxidation of the sulphide sulphur and dissolution of the iron were significantly less. Only 7% of the iron was dissolved and a residue containing 25% total sulphur, present as a lead jarosite, lead sulphate, and elemental sulphur, was obtained. The formation of small pellets of unreacted sulphides coated with elemental sulphur caused problems during the leaching at 150¦C, and also during scale-up from the 1 L to the 4 L autoclave at 190¦C. At 150¦C the concentrate required two stages of leaching to achieve dissolution of over 90% of the zinc. These problems are discussed.

Jan 1, 1989

By K P. Crameri

The Beta Hunt orebody is situated on the south western limb of the Kambalda dome. It is one of the nickel occurrences in the area which fall into the category of æKambalda Style OrebodiesÆ. These orebodies are renowned as being continuous uniformly mineralised ribbons of nickel sulfide mineralisation. Interestingly, Beta Hunt does not conform to this notion of continuity and uniformity and is in fact highly irregular in its ore distribution due largely to the influence of post depositional structure. In an attempt to understand the ore distribution at delineation stage rather than development stage a detailed footwall topography model is created using all available drilling data. To augment this drilling data, the routine use of downhole EM and borehole radar has been introduced to provide data beyond the confines of the drill core to enhance the geological interpretation of the footwall topography and the distribution of the mineralisation. The implementation of a detailed footwall model and the use of downhole geophysics has proved to be very effective in resolving the orebody complexity issues. Ongoing development of the methods used will continue to refine the interpretation of the geology to enable more efficient extraction of the orebody.

Jan 1, 2006

Sheaves are a critical safety component in a winding system and are expected to survive such extreme loading events as rope break. Sheave designs have often been developed and evolved empirically, consequently many existing sheaves are not necessarily subjected to the detailed analyses that are possible using todayÆs design tools. The design philosophy for sheaves is that the rope should be the weakest link in the system so that associated equipment can function safely for any load up to rope break. A number of failure mechanisms must be considered, but buckling is often prominent. During the course of investigating the feasibility of upgrading the hoisting capacity of a winding system, the capacity of all critical components was reviewed. The sheaves in the system were found to have insufficient spoke buckling capacity for the specified rope. A proposal to increase the spoke buckling capacity by connecting spokes together using a simple tie arrangement was evaluated and found ineffective. An alternative tie arrangement concept was developed and evaluated and shown to be adequate. This paper describes the finite element model, analysis approach and results for the original sheave and the two modifications. The contribution of the sheave rim to the total buckling capacity is evaluated. Some practical issues for spoke tie modifications are discussed.

Jan 1, 2005

By J Lea, D C. Kettlewell

The Carina iron ore deposit lies 105 km northeast of Southern Cross, WA. The area designated the Yilgarn Iron Ore Project (YIOP) is comprised of five prospects along an east-southeast trending greenstone belt that extends from the Helena-Aurora Ranges in the northwest to the Yendilberrin Hills in the southeast, over a strike length of approximately 40 km. The YIOP project encompasses the previously identified iron deposits of Bungalbin, Bungalbin East and Mt Walton. The Carina deposit was discovered by Polaris Metals NL in May 2007. The Carina deposit is located within and parallel to the structurally complex northwest trending Mount Dimer shear zone. The volcanosedimentary Archaean-aged greenstone sequence consists of ultramafic and mafic lavas and flows with interbedded sediments dominated by chert and banded iron formation (BIF). Supergene enrichment processes formed a goethite orebody replacement of BIF sequences within a doubly plunging synclinal fold structure. Mineralised outcrops dominated by goethite form a low ridge 1500 m long, up to 90 m wide and drilled to over 200 m in depth. In the vicinity of the Carina deposit, iron occurrences have been identified over at least a 12 km strike length and the exploration potential of the area is identified as 30 - 40 Mt. Polaris Metals began exploration in the area in 2006. Target generation in the area used existing state geological survey maps and regional magnetic survey data to focus on BIF occurrences associated with major structures. Early field investigations resulted in the identification of a large outcrop of predominantly goethite mineralisation at Carina. Detailed geological and structural mapping was completed, followed by close-spaced reverse circulation and diamond drilling. The mineralisation is predominantly goethite with specular and coarse platy haematite localised along structures that cut the goethite mineralisation. Mineralised zones are moderately vuggy and larger cavities occur in proximity to fault zones that transect the orebody. A capping by a thin veneer up to 9 m thick of canga or ferricrete occurs in places. By December 2008, 178 reverse circulation and 11 diamond drill holes (seven surface holes, four tails) were completed. The current JORC-compliant resource estimate is based on assays from 72 RC drill holes and using a 55 per cent Fe cut-off stands as an Inferred Resource of 27.9 Mt at 58.6 per cent Fe, 1.3 per cent Al2O3, 3.7 per cent SiO2, 0.09 per cent P, and 10.1 per cent LOI. Assaying has recently been completed and will be incorporated into a new updated resource later in 2009.

Jan 1, 2009

By A Keogh, P Allen, P Stoker

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Private equity (PE) firms are comparatively free of mandatory requirements for the level and scope of due diligence applied prior to making investment decisions in minerals projects when compared to listed entities, sovereign funds or financial institutions adopting the Equator Principles (Equator Principles Association, 2013). While this freedom allows for flexibility, agility and innovation in making investment decisions, it can also expose PE firms to material risks that may impact their ability to successfully list the projects or attract later financing.Financial institutions and investors with mandatory due diligence and disclosure standards may refrain from investment in or acquisition of a project if it fails to meet various performance requirements. There are many high-profile projects that have suffered significant write-downs on book value after acquisition because specific non-mining issues were not adequately assessed. Thus, a PE firm may be left with an asset that is difficult to divest and incapable of securing development finance.PE firms can manage this risk by being aware of the growth trend in the adoption of ‘international standards’ in addition to host nation standards and legislative requirements. This paper outlines key issues for PE firms to address to maximise the chances of obtaining funding or successfully taking an exploration or mining project through to listing or divestment. Two steps are required: identification of gaps in performance and priority matters of interest to financial institutions and development of action plans to ensure that the priority requirements are met or capable of being met.A PE firm can set its project for success by understanding the social and environmental performance requirements of international standard financiers and by setting the project on the right path to meeting these requirements, and thus making it an attractive investment.CITATION:Allen, P, Stoker, P and Keogh, A, 2015. Setting for success – private equity exploration and mining project buy-in to listing and divestment , in Proceedings PACRIM 2015 Congress, pp 93–100 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By D Elmo, M Scoble, Y Liu, B Klein, J Scholar, S Nadolski

A cave-to-mill study being conducted at the New Afton block caving operation demonstrated the potential for sensor-based ore sorting equipment to reject waste and improve the grade of feed to the mill. The lack of selectivity and potential for dilution entry associated with the block cave mining method results in many caving operations having to mine and process material that is below cut-off grade at certain stages of production. Online monitoring and bulk sorting systems have the potential to alleviate this problem and improve the productivity of caving operations while reducing energy and water requirements for each tonne of concentrate produced.As part of the cave-to-mill study, the suitability of a range of sensors, such as X-ray fluorescence and induction-type sensors, to sort mine production at the New Afton mine was investigated. Results showed that the discrimination of ore and waste can potentially be carried out by implementing surficial sensors into the material handling system. The study also showed that a combination of sensor outputs could be used to identify a certain ore type so that pre-emptive changes can be made in the mill to improve beneficiation performance. Overall, the outcomes of the study on implementing sensor systems at block cave mines are considered to be of significant relevance to a number of existing and future caving operations.CITATION:Nadolski, S, Klein, B, Elmo, D, Scoble, M, Liu, Y and Scholar, J, 2016. Investigation into the implementation of sensor-based ore sorting systems at a block caving operation, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 393–400 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By M L. Muller, A R. O’Donnell

The Mount Isa Mines (MIM) Copper Concentrator has an extensive history of reagent trials, with different reagents coming in and out of favour over the years. The research and use of carbon depressants is particularly prevalent, as carbonaceous pyrite is a major source of concentrate dilution. Years of research led to the use of naphthalene sulphonate due to its excellent carbon depression properties. However, due to rising reagent costs carbon depression ceased in the late 1990s. This led to the loss of knowledge about the use and value of naphthalene sulphonate. Cyanide is used at the Copper Concentrator for the sole purpose of pyrite depression and over the years multiple projects have been devoted to finding alternatives to it. In 2012 the neighbouring MIM Lead-Zinc Concentrator replaced cyanide with naphthalene sulphonate which resulted in cost savings and the elimination of a hazardous reagent. In 2013, plant trials were conducted at the Copper Concentrator in hopes to replicate the outcomes obtained at the Lead-Zinc Concentrator. The results of the trials conducted at the Copper Concentrator showed that naphthalene sulphonate could not replace cyanide and this work was set aside to pursue more promising projects. Further research conducted in 2014 found that mineralogy and a better understanding of the depressing mechanism of naphthalene sulphonate held the key to improved pyrite depression at the Copper Concentrator. The findings showed that Mount Isa copper ore contains two forms of pyrite; euhedral pyrite (cubic pyrite) and framboidal pyrite (carbon rimmed spheres of pyrite), both of which require different reagents to sufficiently depress them. Naphthalene sulphonate was found to be an excellent carbon depressant, suitable for depressing graphite and framboidal pyrite, whilst cyanide specifically targets euhedral pyrite.In 2015 laboratory test work was conducted to examine the use of naphthalene sulphonate in conjunction with cyanide to selectively target both forms of pyrite. This work led to a full plant trial, the results of which showed a significant increase in plant performance, with higher copper concentrate grades and recoveries being achieved. This paper aims to focus on the benefits and importance of understanding past work and linking a detailed knowledge of feed mineralogy to reagent selection for improved plant outcomes.CITATION:O’Donnell, A R and Muller, M L, 2018. Selectively targeting hydrophobic gangue minerals at the Mount Isa Mines Copper Concentrator, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 413–421 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By P A. Grossman, J H. Rubinstein, M Brazil, K G. Sirinanda

To date, the scheduling and access design of an underground mine have only been considered as two separate optimisation problems. First, access to the mine is designed and then the scheduling is completed. One drawback of this approach is that the costs of access construction fail to be reflected in the net present value (NPV) calculation. In this paper, designing the access and scheduling its construction are formulated as a single optimisation problem.The underground mine access construction process can be classified according to the number of faces being developed concurrently. An underground mine with a single decline branching at a junction point into two declines is considered. After construction reaches the junction, the two faces of the decline can be constructed sequentially or concurrently.This paper proposes an efficient algorithm for optimally locating a junction point to maximise the NPV where two faces are being developed concurrently. The NPV is defined by taking the locations of orebodies and their values, decline construction costs, decline development rate and discount rate into account. The variation of the NPV and the optimal locations of the junction point for one and two concurrent development faces for a range of discount rates are discussed and compared. The proposed algorithm is applied in a simulated case study based on hypothetical values for an underground mine.CITATION:Sirinanda, K G, Brazil, M, Grossman, P A, Rubinstein, J H and Thomas, D A, 2014. Strategic underground mine access design to maximise the net present value, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 235–242 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By Xianguo C, Baoqi S, Shaozhong Z, Huiling Z, Zhengbing C

Acidless and fluoless flotation is a new method for separating feldspar from quartz at the natural pH value of tap water in the absence of any acid and fluoride and other inorganic reagents. The paper introduces the production application of this method in plants and research results on the mechanism involved in the flotation method.

Jan 1, 1993

The old Trekelano mining area is situated in the Cloncurry Gold and Mineral Field 14 km east-south-east of Duchess. It connected with the main Cloncurry-Dajarra railway line by a private line from Juenburra, a distance of 10 km. The distance by rail from Townsville is 561 km. The area was first mentioned circa 1902 - 1903 when a very short report said, that a Tony Allis had taken a parcel of copper ore out of a mine which, he called æThe InheritedÆ. After that report, nothing further was printed until about 1906, when traces of copper were noticed on a wagon track going to Kiama Well. The Trekelano deposit did not outcrop, with the cap covered by about two metres of soil. The deposit was named after an early pastoral holding. The early prospectors were however disappointed by TrekelanoÆs low copper grades, approximately five per cent Cu. This is understandable when, in those days, about 25 per cent was the cut-off grade for mines in the district. Meanwhile, The Hampden Mining and Smelting Company were constructing a smelter to treat their sulphide ores at Kuradala that was replacing their high grade oxides ore. By about 1910, the Hampden Mining and Smelting Company was experiencing smelting problems, and needed suitable oxidised copper ore to blend with the Kuradala pyritic ore. Someone must have remembered the Trekelano low-grade oxides, resulting in agreement to mine and cart the ore to Duchess, from where it was railed to Hampden, as Kuradala was known at that time.

Jan 1, 1998