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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.
311

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.
312

Die plaaslike verwerking van goud as instrument vir die verlenging van die lewensduur van die goudmynbedryf

09 February 2015 (has links)
D.Com. (Economics) / The objective of this dissertation was to examine the desirability or not of the local processing of South Africa's gold into jewellery as an instrument for the extension of the life of the gold mining industry. The South African gold mining industry derives its significance not only from its importance as the source of 52 per cent of the country's foreign exchange receipts and a major consumer of labour, agricultural and industrial products, water and electricity, but also from the fact that it is the only long- term future source of gold for the world's jewellery manufacturing industry. The rapidly rising working costs since the early seventies was only neutralised for a few 'years by the increase in the gold price. The decline in profitability since the early eighties as a result of the continuation of the cost escalation and the falling gold price, forced the industry into a prolonged consolidation phase. Measures taken to address its rapidly declining economic position include severe cutbacks in its labour force, the closing down of marginal sections and curtailing expenditure on exploration activities.
313

Labour time in South African gold mines : 1886-2006.

Stewart, Paul Finlay 03 September 2012 (has links)
The core question of this thesis is why working time in South African gold mining has been so stable and addresses the significance of this fact. The working or labour time of miners and mineworkers is shown to have been remarkably stable for a century since 1911. By construing the length of the migrant labour contract as a measure of labour time, which systematically lengthens over the same period until it aligns with the annual rhythm of industrial working time, the evidence is provided for the argument that labour time constitutes the hitherto unrecognised foundation for the exploitation of mine labour in the South African gold mines. The phenomena - and importance for value-creation - of both relatively long, stable industrial working hours and the ever-longer migrant labour contracts over a century, are explained in terms of the value labour power creates in the mining labour process, as well as how the sheer expenditure of extended periods of labour time create the necessary skills mining requires. The fortunes of the platinum mining sector largely follow suit. Whereas the revisionist literature focused on the acquisition of a mine labour supply, this thesis argues that the retention of mine labour, by way of extending, intensifying and sustaining labour time in mining production, completes our understanding of its exploitation. It does so by employing a value-theoretic analysis which reveals the genesis of value creation in productive social class-based relationships. It shows how a series of qualitative, socially constructive effects, intra-working class occupational differentiation for example, emanate from the very expenditure of labour time underground when measured as a quantitative amount of labour time. It is argued that the substantive study of labour time has been surprisingly ignored in Marxist theory within which it plays a central role in the labour theory of value. A range of research methodologies have been employed to make this case. An ethnographic participant observation research method was aimed at articulating an agent-sensitive approach. The candidate lived in the hostel compounds and worked underground with mining personnel and has been both subject to the working time regimes on the mines as well as having actively participated, via various forms of research, in dealing with restructuring and changing working time schedules. The thesis goes on to show in close empirical detail, informed by actual experience and adopting a triangulated research methodology, how working time arrangements within which labour time is expended, remains immured in complexity. Why capital and labour, for instance, adopt competing stances regarding the restructuring of working time arrangements is explained. I conclude that workers’ production demands need to be taken seriously when working time is restructured in mining.
314

Arbitrage operations and opportunities in the Hong Kong gold market.

January 1988 (has links)
by Wong Yue Yan, Henry, Wan Sau Chun. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1988. / Bibliography: leaves 87-89.
315

The geology of the Cam and Motor Mine

Hartman, Louis W. 04 May 2015 (has links)
No description available.
316

Golden Years: Gold Mining Equity Returns After Introduction of the All-In Sustaining Cost Metrics

Barclay, Jared Scott 01 January 2019 (has links)
Previous empirical studies show that returns on gold mining equities are positive and statistically significantly related to changes in the price of gold. However, these studies fail to examine operational factors that may provide further explanatory power to gold mining equity returns. Examining quarterly gold mining equity returns, All-In Sustaining Cost and gold production results between 2013 and 2018, I find that there exists a positive and statistically significant relationship between changes in gold mining equity returns and the price of gold and a negative and statistically significant relationship between lagged changes in All-In Sustaining Cost and gold mining equity returns. My findings suggest that investors must be cognizant of cost metrics when seeking gold exposure through gold mining equities.
317

An integrated geological, geochemical, isotopic and geochronological study on the auriferous systems in the Botwood basin and environs, central Newfoundland /

O'Driscoll, Jacqueline Mary, January 2006 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2006. / Bibliography: leaves 296-319. Also available online.
318

Monte Carlo calculations of microscopic dose enhancement for gold nanoparticle-aided radiation therapy

Jones, Bernard 08 July 2009 (has links)
Gold Nanoparticle-Aided Radiation Therapy (GNRT) is a new paradigm in radiation therapy which seeks to make a tumor more susceptible to radiation damage by modifying its photon interaction properties with an infusion of a high-atomic-number substance. The purpose of this study was to quantify the energy deposition due to secondary electrons from gold nanoparticles on a micrometer scale and to calculate the corresponding microscopic dose enhancement factor during GNRT. The Monte Carlo code EGSnrc was modified to obtain the spectra of secondary electrons from atoms of gold and molecules of water under photon irradiation of a tumor infused with 0.7 wt. % gold. Six different photon sources were used: 125I, 103Pd, 169Yb, 192Ir, 50kVp, and 6MV x-rays. Treating the scored electron spectra as point sources within an infinite medium of water, the event-by-event Monte Carlo code NOREC was used to quantify the radial dose distribution, giving rise to gold and water electron dose point kernels. These kernels were applied to a scanning electron microscope (SEM) image of a gold nanoparticle distribution in tissue. The dose at each point was then calculated, enabling the determination of the microscopic dose enhancement at each point. For the lower energy sources 125I, 103Pd, 169Yb, and 50 kVp, the secondary electron fluence was increased by as much as two orders of magnitude, leading to a one-to-two order of magnitude increase in the electron dose point kernel over radial distances up to 50 um. The dose was enhanced by 100% within 5 um of the nanoparticles, and by 5% as far away as 30 um. This study demonstrates a remarkable microscopic dose enhancement due to gold nanoparticles and low energy photon sources. Given that the dose enhancement exceeds 100% within very short distances from the nanoparticles, the maximum radiobiological benefit may be derived from active targeting strategies that concentrate nanoparticles in close proximity to the cancer cell and/or its nucleus.
319

Gold mineralization in the Black Cloud #3 carbonate replacement orebody, Leadville Mining District, Lake County, Colorado

Gray, Matthew Dean, 1933- January 1988 (has links)
No description available.
320

Preparation and characterization of polyelectrolyte-coated nanoparticles

Dorris, Annie. January 2009 (has links)
Polyelectrolytes coated on high surface curvature nanoparticles (NPs) have been prepared and characterized by a variety of solid-state nuclear magnetic resonance (NMR) experiments in order to examine surface interactions, polymer-water association and polymer dynamic properties of layer components. Gold nanoparticles of four nanometers in diameter pre-stabilized by 4-dimethylaminopyridine (DMAP), and silica and neodymium NPs were chosen as substrates for these studies. The high surface to volume ratio provided by such nanoparticles is advantageous for NMR analysis, which requires a high material content for adequate sensitivity. Firstly, poly(styrene sulfonate) was deposited on gold NPs by electrostatic self-assembly where charged polyelectrolytes adsorb onto an oppositely charged substrate. Surface charges on gold NPs were provided by the ligand DMAP that induces a positive charge at the NP surface that is otherwise neutral. Nanoparticle encapsulation by PSS was monitored by the gold surface plasmon absorption band (SPB) which revealed a good stability under assembly conditions where the pH was maintained above the DMAPsoln pKa and for a polymer radius of gyration comparable to the particle radius. An electrostatic association between DMAPbound and PSS, rather than a ligand substitution, was detected by solid state 13C NMR. When a subsequent layer composed of a weak or a strong polycation was added, the stability of the bilayer was found to be dictated by the nature of the multiple, weak interactions of the polymer functional groups (SO3, NH2, N(CH 3)2+Cl-, NH3 +) with the gold surface relative to that of DMAPbound which in turn is influenced by the assembly pH. / A detailed study of the interactions between the polyelectrolytes, stabilizers and substrates was also extended to polyelectrolyte multilayers coated on gold NPs of different dimensions. Limitations in the application of the layer-by-layer self-assembly technique to very small NPs were investigated and strategies to optimize the method were proposed. 1H NMR analysis in the solid state and 2H NMR analysis in solution revealed that water association and film dynamics were closely related to the identity of the capping layer and independent of even/odd layer effects. These results were compared to those obtained for larger NP substrates which revealed many similarities between the two systems. / A study of the parameters that affect the fabrication of Poly(L-lysine) and DNA polyelectrolyte multilayer films was also conducted for both flat and highly curved surfaces. Such polyelectrolyte films coated on nanopartic1es can be considered as potential vectors for gene therapy. Control over DNA loading into films was performed by varying the ionic strength and pH of polyelectrolyte assembly solutions. DNA density, film degradability and transfection efficiency were examined to determine optimal conditions for vector preparation in gene therapy. Finally, the acid-base properties of lanthanide-based nanoparticles of 10 nm of diameter were explored under a wide range of pH conditions. The interactions of the neodymium oxide nanoparticles with the cationic poly(allylamine hydrochloride) and the anionic poly(styrene sulfonate) polymers were investigated by following spectroscopically optical changes in suspension absorbance and visual changes in NP dimensions. Transparancy and efficiency of stabilization were the evaluated criteria for polymers to be considered as potential stabilizing agents for neodymium oxide NPs used in neutrino detection experiments.

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