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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

The effects of a changing gold price on the South African gold mining industry

Rahn, Friedrich James 01 1900 (has links)
References appear at the end of each chapter / The importance of gold in the development of South Africa as an industrialised economy cannot be over - emphasised. Towards the end of the 19th century the economy depended almost entirely on the production of gold and diamonds which laid the foundation for a highly - developed national economy. With gold still continuing to play an important role coupled with the recent price increases, a need was felt to investigate the potential effect of higher prices on gold production in South Africa. For reasons set out in the study, it was decided to compare potential out put for five different gold prices. A gold price received by the mines of 050 per ounce was used as abase. Further calculations were made at 060, 070, 0100 and 0150 per ounce. The calculations for all the cases were done duri ng the period when the Rand was floating with the Pound Sterling and a Rand : Dollar parity of 1:1, 2 4 was used. Since then two parity changes occured : the Rand was pegged to the Dollar on the 25th October, 1972 to give a Rand : Dollar parity of 1:1,27732, and the Dollar was devalued on the 13th February, 1973 by 1 1,1 % to give the present Rand : Dollar parity of 1:1, 4192. The e ffect of the above two parity changes is that revenue in Dollar terms is overstated by 14,45 5%. It is suggested that for purposes of this study the Rand figures be accepted and wherever Dollars are used in future estimates these be increased by the afore-mentioned 14, 455%. In Dollar terms the five Cases analised will change as follows: Case A : 5350 becomes 057, 23 per ounce Case B : 260 becomes 068, 67 per ounce Case C : 270 becomes 080,12 per ounce Case D : 0100 becomes 0114 ,46 per ounce Case E : 0150 becomes 0171, 68 per ounce To do an in-depth investigation into the effects of higher gold prices on each individual mine, it was necessary to analyse the various parameters required in the determination of gold p r oduction, revenue, lease and tax payments , and dividends. For each mine the pay limits at the various gold prices and at estimated working cost levels, were determined . Graphs of the estimated tonnages at various pay limits as well as the average grade of ore mineable at these limits were determined. From these graphs it is possible to obtain the total tonnage mi neable at various pay limits. Once the foregoing parameters were obtained for each mine, it was possible to determine annual gold production, revenue, lease and tax payments and amounts available to share holders which are then summarised in tables and illustrated in graphs. For ease of reference the mines were divided up into geographica l areas. Gold production revenue, lease and tax payments to the State and the amounts available to shareholders are summarised and compared for the various gold prices. The summaries show bold production remaining fairly constant at or just below the present level of about 900 000 kilograms per year until 1978 for Case A, 1979 for Cases B and C, 1983 for Case D, and 1984 for Case E. before declining progressively thereafter. Revenue following the same pattern as gold production for Case A , as is to be expected, but increasing to a peak of R1 466 million in 1977 for Case B before progressively declining, increasing to a peak of R2 434 million in 1982 for Case D before progressively declining, increasing to a peak of R3 478 million in 1983 for Case E but remaining above the 1973 level of R1 254 million until the year 2005. Lease and tax payments and amounts available to share-holders following the same pattern as that indicated by revenue reaching peaks of respectively R390 million and R268 million for Case B R485 million and R339 million for Case C R756 million and R536 million for Case D R1 000 million and R779 million for Case E. Following the recent monetary unrest, gold prices assumed for 1973 are too conservative. Should the present gold price of about $80 and the 1972 level of production of 909 000 kilograms continue for the remainder of 1973, then gold production, revenue, lease and tax payments and dividends as shown for Case C for the year 1975 will be applicable for 1973. This shams gold production of 919 520 kilograms, gold revenue of R 1690 million, lease and tax payments of R465 million, and dividends of R339 million. The effect of the higher gold price can be clearly seen when the fore-going figures are compared with the 1971 totals of gold production of 97 6,600 kilogr ams , revenue of R396 million from gold, lease and tax payments of approximately R139 million, and dividends of R142 million . Despite a decline in gold production, revenue is expected to be up by 8 9 % whilst lease and tax payments increase by 2 35% compared with a dividend increase of 139%. Finally certain tax concessions to increase productivity and the rebuy alleviate the labour shortage, prolong the li ves of the mines by mining lower grade ore, and encourage exploration was investigated and suggestions made. / Business Management / D. Com.
22

Strategic scenario planning at Lonmin Western Platinum Mine

Naude, M. L. 28 August 2012 (has links)
M.B.A. / To develop four Strategic Scenario's for Lonmin Western Platinum Mine ( WPM ) based on investigation into outsourcing, financial, productivity and technological aspects to enable Lonmin Western Platinum Mine management to refocus their operating strategies. 1.7 Objective of research 1.7.1 To analyse the current external and internal environment 1.7.2 To evaluate Lonmin Western Platinum Mines current situation 1.7.3 To utilize an appropriate research methodology 1.7.4 To provide strategic scenarios to top management 1.7.5 To evaluate the strategic scenario's and provide a recommendation to management
23

Mineralogie en petrografie van die Merenskyrif in die Western platinum-myn, naby Marikana

Brynard, Hermanus Johannes 26 May 2014 (has links)
M.Sc. (Geology) / Please refer to full text to view abstract
24

Strategic implication of a segmentation and positioning model for the South African gold narrow reef mining market.

Landman, G. V. R. 17 August 2012 (has links)
M.Comm. / Many variables exist that influence buyer behaviour in the narrow reef gold mining market. Since some variables are real but subjective in nature, such as the opinion and charisma of mine managers or influential individuals, it is difficult to quantify and analyse them. The question is ? Which variables, 8 quantifiable or not, are more dominant in shaping buyer behaviour and how should they be prioritised? What is needed is a logical segmentation model which reflects true buyer behaviour in order to shape future strategies in AEL so that the overall company objectives can be met. Each segment should then be analysed and considered regarding attractiveness in satisfying needs and the ability to add value both to the customer and to AEL. It is also required to target market segments and develop a marketing mix for them so that AEL is correctly positioned to retain the markets it choose to compete in. The problem is the failure to identify market areas of similar response which are relatively stable and can be used to select areas where maximum value can be added to the customer and to the company and can be used to shape and define future direction. The following objectives have been set for this study:The establishment of a market segmentation model which will identify and explain the basis of similarities and differences in buyer behaviour groups which is sufficiently large and stable in order to focus future strategies. - The interpretation of the segmentation model in the light of the strengths, weaknesses, opportunities and threats of the company in order to target markets best suited to the potential of the company. - Development of strategies and positioning in the target markets to strengthen the chance of success.
25

Characterisation and beneficiation of coal from the New Vaal Colliery, Sasolburg-Vereeniging Coalfield, South Africa, through the application of automated mineralogy

Pretorius, Donavan Johannes 11 November 2015 (has links)
M.Sc. (Geology) / The purpose of this study was to assess the MLA’s ability to characterise (e.g. modal mineralogy, elemental assay, particle size distribution, particle density distribution and mineral associations) a coal product from New Vaal Colliery, with the aim to determine any liberation and beneficiation characteristics. In general the MLA assessment on coal is comparatively new and novel, especially at Spectrum (University of Johannesburg), hence research in this regard is required. For the first time New Vaal coal product was characterised with the MLA 600 FEG SEM. The coal product supplied to Lethabo Power Station for the study’s samples, consisted of Top Seam and Middle Seam coal from New Vaal Colliery which is located in the Cornelia subbasin of the Vereeniging-Sasolburg coalfield, South Africa. The proximate analysis characterised the coal as a high-ash (42.25% air-dried) and low calorific value (13.92 MJ/kg air-dried) product. Chemically SiO2 was the most abundant oxide followed by Al2O3 for the XRF analysis, which was mostly derived from the abundant kaolinite clay mineral (determined by petrography, XRD and MLA analysis). Mineralogically inertinite was the most abundant coal maceral encountered during the petrographic analysis. With geochemical characterisation, chalcophile, siderophile, lithophile and radioactive trace elements were found to be mostly comparable to the global average.
26

The nature and origin of gold mineralization in the Tugela valley, Natal Structural and Metamorphic Province

De Klerk, Ian Duncan January 1991 (has links)
The project area is situated within the Tugela Valley, located in the Northern Marginal Zone of the Natal Structural and Metamorphic Province, and this work outlines the different styles of gold mineralization found in the Tugela Valley. Two different styles have been recognized and both have economic significance:- 1) Epigenetic shear zone-hosted gold occurs in late-stage relatively undeformed thin quartz veins confined to shear zones, and is present in both the greenschist facies Natal Thrust Belt and the amphibolite facies Natal Nappe Complex. However the vast majority of these occurrences are concentrated within the thrust front (i.e. the Natal Thrust Belt). The gold grades (up to 7 g/t) and the hydrothermal alteration assemblages associated with the epigenetic deposits have been documented. 2) An as yet unrecognized occurrence of syngenetic gold mineralization is found associated with the sediment-hosted exhalative massive, to semi-massive, sulphides of the iThuma prospect, located within the amphibolite facies Natal Nappe Complex. Here gold (up to 3 g/t) is concentrated together with the main sulphide are, as well as some gold enrichment (230ppb) in the hydrothermally altered footwall feeder pipe. It is proposed that the epigenetic mineralization was formed as a consequence of the northward directed abduction of the major thrust slices of the Natal Nappe Complex. This increased the permeability of the rocks and provided channelways for the focussing of fluids. Deposition took place at the thrust front where metamorphic hydrothermal fluids interacted with meteoric water.
27

A hydrogeological investigation of the Grootegeluk mine

Johnstone, Andrew Clifford January 1989 (has links)
The study concerns an assessment of the hydrogeological impact of an open cast coal mine in the North Western Transvaal Province of South Africa. The hydrogeological impact of the mine is assessed in terms of groundwater quality and levels. A monitoring system was installed to enable the present and future impact of mining operations on the hydrogeological regime to be assessed. Grootegeluk Mine is situated in the Waterberg Coal Field of South Africa and began production in 1980. The mine extracts fifteen million tons of mine material annually from a single open pit. Forty percent of the mined material is saleable product and the remaining sixty percent is stacked on discard dumps. The Daarby fault forms the northern boundary of the open pit and serves to bring the younger Letaba and Clarens Formations into contact with the older Beaufort and Ecca Groups. The mine discards are deposited north of the fault on a different hydrogeological environment from which they are mined. Dewatering of the mine open pit has resulted in a steady decline in water levels in the Ecca Group, south of the Daarby fault. In contrast, water levels north of the Daarby fault in the Letaba and Clarens Formations have risen. The short term hydrochemical impact of the mine discard dumps and slimes dams have resulted in a rise in the calcium, sulphate, chloride, fluoride and nitrate concentrations of the ambient groundwater . The longer term hydrochemical impact from the waste dumps, acid mine drainage, is not evident at present in the groundwater below the waste dumps. However, it is expected to manifest itself during the next ten years. A monitoring system was installed at the mine to allow groundwater levels and quality to be monitored. By measuring groundwater quality and levels the impact of the mine on the regional hydrogeology can be monitored and assessed presently, and during the next forty years of production. Monitoring will also enable the timeous implementation of remedial measures at an early stage and eliminate the need for large late stage "clean up" operations. Future monitoring of both water levels and quality will be crucial in evaluating the mine's impact on the regional groundwater regimes over the next forty years of production. The remedial measures recommended for leachate presently emanating from the waste dumps and slimes dams north of the Daarby fault, are a number of collector wells drilled into the basalts and sandstone north of the Daarby fault. The proposed positions of the wells (boreholes) are as close as possible to the dumps and slimes dams with expansion taken into consideration. The boreholes should be designed to lower the water level in the vicinity of the dumps in order to create a nett groundwater gradient towards the dumps and as a result, halt the spread of leachate away from the dumps. Grootegeluk plans to backfill the open pit with plant discards on completion of the mining of zone 2. The backfilled material will consist of the currently produced plant waste and will be covered with overburden and topsoil. It is expected that the backfilling will have a major impact on groundwater quantity if no remedial measures are implemented. The two remedial measures discussed are chemical treatment of the discard material before backfilling or the continual abstraction of water from the pit resulting in a nett groundwater inflow into the pit. No material from the present waste dumps and slimes dams will be transported into the open pit as backfill material
28

Pyogenic infections of the hand : an industrial and clinical investigation in the African miner.

Van Niekerk, Johannes Philippus de Villiers 20 April 2017 (has links)
No description available.
29

Corporate reputation in the South African diamond industry : a multi-stakeholder perspective

Ngcobo, Sakhile Glen January 2016 (has links)
A thesis submitted to the Faculty of Commerce, Law and Management, University of the Witwatersrand in fulfilment of the requirements for the degree of Doctor of Philosophy / Lack of common understanding of corporate reputation in the diamond industry in South Africa has attracted a lot of interest in this aspect of the mining industry. The recent Marikana Massacre in the platinum belt in the Rustenburg area at Lonmin Mine in 2012, together with on-going debates on resource nationalisation and negative relations between mine communities and diamond mining companies have prompted the call for more research in reputation management in the mining industry in South Africa. The purpose of this research is to define the meaning of corporate reputation in the diamond industry, to understand key perceptions of the diamond industry, to identify key effects of corporate reputation in the diamond industry and to evaluate key management approaches to corporate reputation in the diamond industry from multi-stakeholder perspectives. Mixed methods research methodology was used in this study, comprising quantitative and qualitative data collection and data analysis. Key findings include that there is no one single definition of corporate reputation. Each stakeholder has his/her unique definition which is based on his/her own assessments of the organisation, the past and future actions of the corporation, and their experience and perception of the organisation. Poor relations between mine communities and diamond companies; prospects for the collapse of the Kimberley Process (KP); violent strikes; environmental issues, including rehabilitation of old mines; poverty and high unemployment in the mining communities; failure of BEE transactions in delivering real value to the mine employees and local communities; illegal mining; the rise of synthetic un-natural diamonds and negative perceptions of the diamond industry in South Africa are the current major challenges and risks affecting the diamond industry in South Africa. This study concludes that positive corporate reputation would result in improved investor confidence, higher levels of attracting and retaining top level talent in the organisation, improved attraction of customers, better relations with communities and improved stakeholder relations. The study did not find evidence proving that a positive reputation will result in higher prices for diamond products. It found that corporate reputation management initiatives in the diamond industry are not well understood and, as a result, they are not delivering the full results as expected. ii | P a g e Effective stakeholder relations management with a special focus on community engagement including youth groups’ involvement in the mining towns; targeted social investment programmes with special focus on enterprise development and effective management of industry perceptions are identified as the most critical steps to be adopted in the diamond industry in order to improve its reputation. / GR2018
30

A study of the correlation between dragline diggability and blasting technology at Syberfontein colliery.

Frimpong, Mensah. January 1994 (has links)
A project report submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master ofil science in Engineering. / Given the high capital intensity of the dragline operation, the mine can not afford to" tolerate fragmentation problems with its concomitant low dragline productivities. At Syferfontein colliery very large boulders and completely unfraqmented sections resulting in Low digging efficiency of the dragline were encountered in the interburden blast, This project, investigates the causes of the blasting related problems with an intent of improving dragline productivity at the minimum possible cost. This is achieved through blast monitoring, evaluation of the existing practice (blast design) using empirical relations, fragmentation assessment using a model, analysis of operators performance and dragline availabilities. Dragline productivity is evaluated in the light of the various productivity indices , viz, fill factor, fill time and BCM/H. The results indicated explosive incompatibility with the blasting environment and. questionable practices regarding blast design and Delay performance. Engineering field controls such as reduction in drill pattern, reduction of VODof explosive and improvement in draqline utilisation are found necessary. Contributing 61% to the total cost I concentrating on reducing draqline cost must receive preference over drilling and blasting cost as it would produce the most tangible advantage in any cost reduction effort. Regression equations relating cbst and productivity are established. / Andrew Chakane 2018

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