M.Com. (Business Management) / All valuations of mineral assets in South Africa are guided by the South African Mineral Resources Committee (SAMREC) and South African Mineral Valuation (SAMVAL) codes. They have also been adopted by the Johannesburg Securities Exchange (JSE) in order to protect shareholders. Different capital budgeting methods are used for mineral assets valuation in South Africa. These are the net present value (NPV), internal rate of return (IRR), payback period, cost, market and real options methods. It is not known which capital budgeting method is most often used for mining property valuations, as South African mining companies and associations are not required to share their capital budgeting processes with the public. In addition, the SAMVAL code does not recommend the use of the real options method and no reasons are provided. The study was aimed at establishing the capital budgeting method most often used for mining property valuations in South Africa, as well as the reasons why the real options method is not recommended by the SAMVAL code. A judgement sample of expert valuators was utilised in the study and interviews were carried out using open ended questions. The research revealed that NPV is the capital budgeting method most often used for mining property valuations followed by the IRR method. Outside South Africa, Bhappu & Guzman (1995) found that these preferences were reversed. Since the IRR method represents a notional rather than an actual return on investment, South African valuators were found to be more rational than their overseas counterparts in the application of these discounted cash flow (DCF) methods. The findings also revealed that the cost, market and payback methods were less preferred to the NPV and IRR methods. The reasons given were all consistent with the theory. The cost method was avoided because it uses historical cost data which is not usually applicable, the market method was limited due to the lack of available information on truly comparable projects and the payback method was shunned for undervaluing mining properties by ignoring cash flows that arrive after the payback period. The respondents also indicated that the real options method is the least used. The method (which includes the value of embedded optionality) was regarded as complex and not widely understood and this was also thought to explain why it is not recommended by the SAMVAL code. This finding indicated that in South Africa the embedded optionality in mining projects may not be taken into account and as a result, opportunities for the exploitation of its mineral assets could be missed.

M.Sc. (Geography) / Coal mined in South Africa for the competitive international market, has to be selected to meet the many quality specifications of customers. This upgrading is done by washing the coal in a heavy medium separation plant. Marketable coal, discard and slurry are produced from this washing. Discard consists mainly of poor quality coal, carbonaceous shale and waste rock. Iron pyrite (FeS2) occurs in all of the above in higher concentrations than in the marketable coal. Both the carbonaceous materials and pyrites generate heat when oxidizing. If this oxidation is not arrested at an early stage on a discard dump and the temperature of the dump increases above BOoC, spontaneous combustion is quite likely. The South African Council for Scientific and Industrial Research (CSIR) has estimated that smouldering discard dumps in the Eastern Transvaal highveld region contribute approximately 400 000 tons of S02 per annum to the atmospheric pollution in that area. As a result, significant localized acid rain occurs, Louw (1990). The oxidation of iron pyrites to sulphuric acid, and the oxidation of other trace elements, is accelerated under the high temperature conditions generated by spontaneous combustion. Leaching of these oxidation products results in local groundwater and surface water contamination. This study describes different disposal technique and pilot study aimed at minimising the oxidation within the dumps. Slurry, which consists of discard and/or coal of less than 1 mm in diameter is co-deposited with discard in sequential layers of approximately 200 mm thick. This has resulted in reducing the permeability, porosity and air and water exchange within the dump. This in turn has led to a reduction in spontaneous combustion, pollution and costs. A visual increase in stability of the discard dumps, moisture content and operational ease of placement were experienced. The saleable value of the dump as a low value heat source is also preserved.

There are two industrial sources of zirconia: zircon and baddeleyite [1-5]. The baddeleyite reserves in Phalaborwa (the world’s major baddeleyite source) are expected to be depleted by the year 2005 [1-3]. This leaves the Russian Baddleyite (Kola Peninsula) and zircon as the only industrial sources of zirconia. The major drawback to zircon use is the large amounts of impurities it is found concentrated with, especially radioactive impurities (Uranium and Thorium) [2-3]. Acid leaching of zircon does not remove these impurities [4-5]. The impurities are usually included in the zircon lattice. The tetragonal structure of zircon with the high coordinated bisdisphenoids ZrO8 and low coordinated tetrahedra SiO4 create a safe (inaccessible and stable) habitat for these impurities [7]. Processes for the recovery of zirconia and zirconium chemicals rely heavily on precipitation or cyrstallisation techniques for purification [8-16]. Precipitation techniques need to be repeated to obtain the required purity. The purity of products from such methods is still suspect, as there still remains a high radioactivity content after purification [2]. The long process time is another disadvantage of these precipitation processes. These factors together are the reason for the high cost of zirconia and zirconium chemicals. Zirconium and its compounds are regarded to be of low toxicity [1-6]. This implies that they have a great potential of replacing numerous high toxic chemicals. Prominent examples are seen in leather tanning and paints. In leather tanning chromium chemicals can be replaced. In paints lead driers and chromium chemicals for corrosion resistance can be replaced. The objective of this study was to characterise and optimise the De Wet’s zirconium extraction processes for the beneficiation of zircon sand into high purity zirconia and zirconium chemicals. However, at each process step some factors were varied e.g. fusion temperature, reactant mole ratios and composition of leach solutions. Attention was also paid to reducing the total number of process steps. The products produced at each step were analysed. Particular attention was given to the fate of the radioactive impurities. Characterisation of the decomposition step, showed that within the zircon tetragonal structure, the SiO4 bisdisphenoids linkages. This was shown by the preference of sodium for the SiO4 tetrahedra. Fusion for 336 hours with periodic intermediate milling proved the preference of sodium for attacking the SiO4 tetrahedra linkages. This selectivity was clearly demonstrated when decomposing zircon in sodium poor(<4 moles NaOH per mol of zircon) and low temperature (e.g. 650°C) reaction conditions. The advantage of fusing at 650°C with a mole (or even two moles) of sodium hydroxide is that it leads to minimal (<5% m/m Na2O) sodium in the insoluble solids after the removal of soluble silicates. This is a solution to alkali fusion processes, as high amounts of water are usually required to wash out the neutralised sodium salt e.g. 50g of NAC1 usually requires a litre of distilled water to reach levels below 600 ppm NA2O. This reaction condition can be employed when synthesising products where low amounts of sodium are required in the final products e.g. when synthesising zirconia for the ceramic industry. When fusing for two hours without the intermediate milling step the following results were observed. The reaction at 850°C when fusing a mole of zircon with two moles of sodium hydroxide, was the most efficient in consuming sodium hydroxide. Near complete zircon decomposition was at 850°C when fusing a mole of zircon with six moles of sodium hydroxide. Characterisation with XRD, Raman and IR spectroscopy was misleading as complex spectra were measured, indicating many different phases present. The inconsistency was partly attributed to non-homogeneity in the samples due to NaOH migration. When fusing for 336 hours with the intermediate milling step the following results were observed. The reaction at 850°C when fusing a mole of zircon with a mole of sodium hydroxide was the most efficient in consuming sodium hydroxide. This reaction condition was able to liberate 0.58 moles of zirconia per mole of sodium hydroxide. The highly improved efficiency was attributed to the formation of phases Na2ZrSiO5, Na4Zr2Si3O12 and SrO2. The process is pseudo-catalytic as it liberates zirconium while showing minimal sodium consumption. Decomposition at 650°C also showed improved efficiency but not as efficient as the 850°C sub-stoichiometric fusion. The improved decomposition was attributed to the polymerisation of the orthosilicate monomers Na4SiO4 to the metasilicate chains Na2SiO3. / Dissertation (MSc (Chemical Technology))--University of Pretoria, 2007. / Chemical Engineering / unrestricted

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M.B.A. / The South African economy places great reliance on the gold mining sector, both for employment opportunities and revenue. Due to the increased price volatility of this precious metal in international markets, the economy has been placed under enormous pressure due to the loss of jobs and lower revenues generated, particularly from the country's marginal mines. Through discussions with representatives from the various facets of the mining industry, it has been noted that a large portion of the prospective and existing gold reserves are not being mined. This may be due to the high capital investment required to start-up such an operation and the resultant dividends are not appealing enough to attract the investment. Unrest amongst unionised labour has reduced productivity in the work force and this has further increased the cost of production, placing many South African gold mines in the "red". Historically, gold mines owned all of their own equipment and bore all of the risk. For all this investment, they took all of the profit, or loss from the operation, but this increased cost of capital and risk does not bring along an increased return on investment due to the volatility in both the gold price and the currency exchange rate. The aim of the research report is to establish a framework for conducting a technoeconomic due diligence in identifying a viable alternative to the traditional methods of mining gold in South Africa. The objectives of this dissertation are: To determine the viability of conducting an alternative approach to mining gold in South Africa; To determine if the proposed alternative approach would tolerate a lower gold selling price than the present methods and still remain profitable; To determine the barriers to entry and the pitfalls of mining gold in South Africa.

M.Phil. (Mineral Economics) / Please refer to full text to view abstract

Thesis is submitted in partial fulfilment of the requirements for the degree of Master of Science in Engineering to the Faculty of Engineering and the Built Environment, School of Mining Engineering, University of the Witwatersrand, Johannesburg, 2018 / Iron ore prices rallied from USD15/DMT during 2004 and experienced a significant drop from USD 140/DMT during the latter part of 2013. The purpose of the work is to identify the key drivers impacting on iron ore demand globally. Understanding the supply and demand balance and impact on price, is key to informed decision making relating to the iron ore business. The research methodology applied largely followed a quantitative methodology. Key drivers of iron ore demand, supply and demand balance and the impact on price were evaluated. The method applied consisted of gathering data from secondary sources and a detailed quantitative analysis on GDP, stage of economic development, steel consumption, supply and demand of iron ore and intensity of use. Approximately 98% of all iron ore is used for steel making and on that basis steel consumption is the primary driver for iron ore demand. Steel is mostly used for construction and manufacturing and is driven by emerging economies of which China is currently the largest contributor. Global GDP growth correlates well with steel consumption and is primarily driven by emerging economies. Urbanisation was and still is a key driver for construction in China, to provide housing and related infrastructure for transportation and services. Scrap steel recycling, currently at 15%, affect the demand for new steel and indirectly iron ore. Iron ore is abundant and can easily meet the demand. The significant growth from 2004/5 to 2013/14 and the unprecedented demand for steel resulted in elevated iron ore prices, introducing high cost iron ore, predominantly from Chinese State owned companies. From late 2013, the iron ore prices reduced significantly. This was mainly due to the steel consumption in China slowing down; delivering of large scale, low cost iron ore projects in Australia and Brazil and a significant reduction in oil prices. The key drivers impacting iron ore demand is: global GDP growth, industrialisation and urbanisation of emerging economies, recycling of steel, supply and demand balance of iron ore, the cost of production and the price of global iron ore. For the medium term outlook, the iron ore market will be structurally over-supplied and, as a result, the demand could be met at significantly lower cost of production levels than that seen during the period leading up to the price collapse in 2013. This is primarily because of the increase in low-cost supply from the major suppliers displacing higher cost producers. China will continue to grow and drive the global demand for steel and iron ore during the medium term albeit at much lower rates when compared to the last decade. The demand for steel will increase until 2020 according to various analyst views. The iron ore prices are expected to trade between USD50/DMT to USD70/DMT from 2016 to 2020 mainly because of the over-supply situation and demand being mostly met by large scale, low-cost producers. The decision around the continuation of high cost, state owned Chinese iron ore producers, new large-scale low cost production and the oil price will impact on the price outlook. / MT2018

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