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An approach to analyzing gold supply from the South African gold minesMather, Diarmid John January 1995 (has links)
The gold mining fIrm in South Africa is viewed as a normal fIrm producing gold bearing ore but faced with a quality constraint (grade). Grade, however, is never uniformly distributed in a metalliferous deposit and because high grades are mined fIrst, the quality constraint becomes increasingly severe with cumulated production. The fIrm will continue to mine gold bearing ore until it reaches its mining limit where the marginal cost of recovering the gold is equal to the marginal revenue received from that gold and at that point the economic deposit becomes exhausted. Because the mining limit is determined by cost/technology and price, it is not fIxed and thus the point of economic exhaustion may change. When high grades are mined fIrst the relationship between the tonnage of gold ore and the grade describes the rate at which the grade is expected to fall with cumulated production. In this thesis, the grade for South African Witwatersrand gold producers is modelled to fall exponentially. The mining limit, determined by costs/technology and price, can be expressed in terms of grade. By predicting the decay in grade relative to the tonnage of gold ore and applying a mining limit, a life-time size of the economic deposit can be estimated. The remaining life of a producing gold mine can then be determined and the flow of gold predicted. An empirical treatment using the disk model of a gold deposit is undertaken for a gold mine, a goldfIeld and the total Witwatersrand gold deposit. A dynamic econometric analysis of expected mining costs and gold prices is not attempted; however certain examples are used to illustrate the applicability of the model and the influence of the South African gold mining tax formula on the life of the mine.
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Flotation as a separation technique in the coal gold agglomeration processMoses, Lucian Benedict January 2000 (has links)
Thesis (MTech (Chemical Engineering))--Cape Technikon, 2000. / Internationally, there is an increase in the need for safer environmental
processes that can be applied to mining operations, especially on a small
scale, where mercury amalgamation is the main process used for the
recovery of free gold. An alternative, more environmentally acceptable,
process called the Coal Gold Agglomeration (CGA) process has been
investigated at the Cape Technikon. This paper explains the application of
flotation as a means of separation for the CGA process.
The CGA process is based on the recovery of hydrophobic gold particles
from ore slurries into agglomerates formed from coal and oil. The
agglomerates are separated from the slurry through scraping, screening,
flotation or a combination of the aforementioned. They are then ashed to
release the gold particles, after which it is smelted to form gold bullion. All components were contacted for fifty minutes after which a frother was
added and after three minutes of conditioning, air, at a rate of one I/min
per cell volume was introduced into the system. The addition of a collector
(Potassium Amyl Xanthate) at the start of each run significantly improved
gold recoveries. Preliminary experiments indicated that the use of baffles
decreased the gold recoveries, which was concluded to be due to
agglomerate breakage. The system was also found to be frother-selective
and hence only DOW-200 was used in subsequent experiments. A
significant increase or decrease in the air addition rate both had a negative
effect on the recoveries; therefore, the air addition rate was not altered
during further tests. The use of tap water as opposed to distilled water
decreased the attainable recoveries by less than five per cent. This was a
very encouraging result, in terms of the practical implementation of the
CGA process.
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An implementation programme for the South African gold mining industry to achieve environmental complianceBailie, Melisa 09 February 2009 (has links)
M.Sc. / The gold mining industry in South Africa is exposed to various legal issues due to the nature of its operations. Furthermore, there has been a renewed focus on environmental management in South Africa over the past decade, as well as an international focus on sustainable development. Environmental management in the gold mining industry must incorporate sustainable development, as well as the ‘cradle to grave’ concept. The gold mining industry has to ensure that its activities are compliant with environmental legislation and best practice requirements, as the increase in environmental awareness and legislated principles has escalated gold mines’ exposure to demands for the remediation and reparations of pollution and environmental degradation. No single document exists that provides the gold mining industry with detail on the environmental legislation and best practice requirements that gold mines are able to refer to in order ensure effective environmental management. Furthermore, there is no implementation plan for gold mines to implement in order to achieve compliance with environmental legislation and best practice requirements. This study has presented such a document, as it has provided the reader with detail concerning the responsibilities of the regulatory authorities, the current and new legislation, best practices, codes of practices, and offences and liabilities that gold mines will become exposed to should they not adhere to environmental legislative requirements. This detail has been used to compile an implementation programme (Chapter 4), which when implemented will ensure environmental compliance for the gold mining industry in South Africa. This mini-dissertation has thus provided the gold mining industry with an overview from which to work in order to become legally compliant with issues pertaining to environmental management in South Africa.
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The impact of employment equity legislation on employee engagement within generation YMula, Amina Bibi January 2014 (has links)
This research focuses on three elements i.e. employment equity, employee engagement
and generation theory and specifically where these elements intersect. The literature found
that there were different perceptions of employment equity legislation. In addition, the
literature found generational differences with respect to some elements of employee
engagement. Limited empirical evidence was found on whether employment equity
legislation had an impact on employee engagement. Consequently, three research
questions were drawn from the literature reviewed.
The research is a quantitative study based on a sample drawn from South African
individuals who have completed grade 12 and are currently employed or have an
employment history. The sample included employees of a financial services company
based in Gauteng and GIBS MBA students.
The results showed that there were differing perceptions of employment equity legislation
and that the majority of respondents perceived the legislation to be affirmative action.
There were no differences in the perception of employment equity legislation between
generations. Additional findings were that the perception of employment equity legislation
did not enhance employee engagement neither did the perception of the organisations
implementation of employment equity legislation enhance employee engagement. Limited
generational differences were found in terms of these findings. / Dissertation (MBA)--University of Pretoria, 2014. / zkgibs2015 / Gordon Institute of Business Science (GIBS) / MBA / Unrestricted
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The effects of strikes in the South African gold mining industry on shareholder valueSeedat, Aayesha 19 July 2013 (has links)
Thesis (M.Com. (Accounting))--University of the Witwatersrand, Faculty of Commerce, Law and Management, School of Accountancy, 2012. / The recent spate of strikes in the mining sector in South Africa has created a perceived nervousness amongst shareholders. Within the mining sector in South Africa, gold mining is of significance historically and economically. This study aims to assess the impact of strikes on shareholder value in the gold mining industry during the period beginning January 2007 and December 2012, and uses the popular event study methodology developed by Ball and Brown (1968). The effect of the announcement and duration of the strike on the share price was tested. Significant negative cumulative abnormal returns were observed during the announcement of the strike. The impact of the announcement of protected strikes compared to unprotected strikes on the share price was compared. Although both types of strikes had a negative impact on shareholder value, an unprotected strike had less of an impact on shareholder value compared to a protected strike. This observation is of particular significance given the recent increase in unprotected strikes. Strikes with a duration of 15 days or longer resulted in smaller negative cumulative abnormal returns as opposed to strikes which lasted for less than 15 days.
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The controversy over Chinese labour in the Transvaal /Weeks, John Austin January 1968 (has links)
No description available.
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An economic analysis of gold supply in the Province of Quebec /Buck, Malcolm K. January 1985 (has links)
No description available.
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The optimal depletion of a non renewable resource : ban empirical study16 April 2014 (has links)
M.Phil. (Mineral Economics) / This work is an attempt to discover whether or not South Africa's gold reserves have been properly exploited - has the wealth that has been removed been used to the best advantage. It became apparent to the author whilst conducting feasibility studies on both projected and operating mines that scant attention is paid to the determination of an optimal time path of depletion for a mineral deposit by the planners. The main, if not sole, criterion is the maximising of returns on the capital invested. The thesis proposes a methodology to describe the actual depletion paths achieved by a selection of South African gold mines. The work of mineral economists, especially Harold Hotelling, is used to provide a theoretical base for the. proposals. The mines were selected to cover as wide a range of the exploitation cycle as possible from the planning stage to final abandonment.
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The main factors which affect productivity and costs on South African gold mines.Clatworthy, Geoffrey, Charles January 1994 (has links)
A project report to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, In fulfillment of the requirements for the degree of Master of Science / A detailed analysis was performed on statistics obtained from twenty two gold mines in different mining districts, to determine the parameters which affect labour productivity and working costs, (Abbreviation abstract) / AC2017
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Mine call factor issues at Iduapriem mine: working towards a mineral and metal accounting protocolTetteh, Monica Naa Morkor 14 May 2015 (has links)
A research report submitted to the faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering. / The theory of Mine Call Factor (MCF) compares the sum of metal produced in recovery plus residue to the metal called for by the mines evaluation method expressed as a percentage. This MCF concept is well known in underground scenarios and therefore this report highlights the MCF issues and the variable components affecting it from a surface mine perspective. The MCF investigation established the relationship between actual measurements and reporting against measurement protocols. Such measurements include “tonnage, volume, relative density, reconciliation strategy, and truck tonnage determination, sampling and assay standards. This study investigated how these measurements are conducted on Iduapriem Mine according to the mine’s standard operating procedures (SOP). An improvement of documents towards a metal accounting protocol based on the AMIRA protocol is recommended. The mine’s current quality control protocol was further expanded to reflect current practices. The mine to mill reconciliation compared production estimates from various sources (resource model, grade control model, pit design, plant and stockpile, truck tally, stockpile and plant feed, plant feed and plant received) in the period 2009 and 2010. Reconciliation factors expressed as a percentage were statistically analysed for discrepancies for tonnages and grades. It was realised that there is more confidence in mass (tonnage) measurement compared to grade. A generic mine to mill reconciliation path was suggested to be used by the mine.
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