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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.
11

The governance of natural resources in Zimbabwe: the case study of the Marange diamonds

Taruvinga, Gwinyai Regis January 2016 (has links)
A dissertation presented in partial fulfilment of the requirement of the Master of Arts in Political Studies, Faculty of Humanities at the University of the Witwatersrand, Johannesburg, 2016 / The governance of natural resources plays an important role in the distribution of resources in any state. The failure of a government to effectively administer natural resources will result in a country failing to benefit from the resources economically. This research paper explores how from 2006 to 2013 the Zimbabwean government handled the discovery of diamonds in the Marange area which is situated just outside Zimbabwe’s third largest city, Mutare. Zimbabwe has had a tumultuous millennium which has seen farm invasions, controversial elections and a crippled economy. The discovery of the diamonds was expected to aid the country’s faltering economy, but instead the diamonds only benefitted a close knit group of individuals who were aligned to the ruling party, ZANU PF. The ruling party in Zimbabwe has enjoyed a stranglehold on the Zimbabwean political landscape and the discovery of the Marange diamonds solidified this stranglehold. The diamonds helped ZANU PF revive its waning political fortunes after the party had joined a coalition government with MDC T after the controversial elections in 2008. The diamonds in Marange are an example of how ZANU PF has been able to use the country’s resources to prop up its waning influence on the Zimbabwean political landscape. The discovery of the diamonds in Zimbabwe mirrors other African countries where rather than being a blessing to local communities natural resources become a curse. / MT2017
12

Understanding operation Chikorokoza Chapera : the political ecology of 'formalising' Zimbabwe's gold and diamond mining sectors, 2006-2012

Spiegel, Samuel Jason January 2014 (has links)
No description available.
13

Conflict and change in the socioeconomic organization of diamond production in Guyana.

Smith, Douglas Wilson. January 1968 (has links)
No description available.
14

A comparative analysis of leadership and management at Jwaneng Diamond Mine /

Mabhudu, Mark. January 2008 (has links)
Thesis (MPhil)--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet.
15

Conflict and change in the socioeconomic organization of diamond production in Guyana.

Smith, Douglas Wilson. January 1968 (has links)
No description available.
16

Liaisons entre l'agriculture paysanne et l'exploitation artisanale du diamant dans la province du Kasai-Oriental en République démocratique du Congo /

Kalenga, Fernand Kasongo. January 2007 (has links)
Thesis (doctoral)--Humboldt-Universität, Berlin, 2007. / Includes bibliographical references (p. 174-184).
17

The recruitment and ogranisation [i.e. organisation] of African labour for the Kimberley diamond mines: 1871-1888

Siebörger, Robert Frederick January 1975 (has links)
Behind the fortunes in diamonds, the great open mines and the teeming town that was early Kimberley, were African labourers. Diggers seemed scarcely to care about them unless they were "in short supply", and many historians have been interested only in the guns they carried home with them. This study is concerned with these men: where they came from, why and how they came, and their treatment while they worked in Kimberley. The initial inspiration for the study came from the chapter on diamond production in Sheila van der Horst's Native Labour in South Africa, a remarkable contribution to the history of the Diamond Fields. The later studies by G.V. Doxey and more recently by John Smalberger which have expanded on aspects of Van der Horst's work, have led me to delve more deeply into other areas upon which they have not touched. One potentially fruitful line of study which was beyond the scope of this work was an investigation into the degree to which the Griqualand West labour question affected the attempts at South African federation in the 1870's. The main sources for the work have been the Griqualand West archives in the Cape Archives, for the period 1872-1880, and the various Kimberley newspapers. Labour returns were printed monthly in the Griqualand West Government Gazette for most years, till 1880. Cape Blue Books were useful sources for the period after 1880. De Beers Consolidated Mines Ltd. hold very little material relating to the pre-amalgamation period, though the extant minute books of the De Beers and Kimberley Central Diamond Mining Companies provided valuable information. A considerable number of contemporary published works were also consulted but, though most made some reference to African labour, few contained anything worthy of mention.
18

A decision support system to optimise the available resources at Kimberley Mines

Du Toit, Jeremias Cornelius 03 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2007. / ENGLISH ABSTRACT: Diamond mining started in Kimberley in the early 1870s following the discovery of the various diamond bearing kimberlite pipes. Initial open pit mining was replaced by underground mining as the pits went deeper and the last underground mining eventually ceased in 2005 as a result of economic reasons. The mining of these primary resources created a number of tailing resources (previously called dumps) that are scattered all over Kimberley. These resources still contain diamonds as a result of historical inefficient processing technologies. However, each of these resources have unique geological and metallurgical properties because of the differences in the original kimberlites and the different treatment technologies that were used when the tailing resources were deposited. The tailing resources are mined by a fleet of earthmoving equipment and delivered to one of Kimberley Mines‟ five treatment plants for diamond recovery. Each plant is different in terms of treatment capacity, technologies utilised and overall efficiencies. These differences, combined with the geo-metallurgical properties of each individual resource and the hauling distance from the resource to the plant, determine if the specific resource can be treated profitably through that plant. With this array of resources available, Kimberley Mines is in the fortunate position of having flexibility to maximise the Net Present Value (NPV) of the operation. Unfortunately this flexibility also increases the complexity of finding the optimal solution. Mine Planning is currently conducted with a spreadsheet based input – output model but this model is not able to match the resource properties with the plant parameters and this method results in a plan that may be neither practical nor optimal. The model is also very time-consuming and scenario analyses are therefore very limited. This report presents the development of a mixed integer linear programming model to assist with the development of a practical, optimal mine plan. The model is roughly based on a generic model that addresses facility location and processing plant problems as developed by Barbaro & Ramani (1986); however, the model presented in this report includes a more detailed mass balance within the plant and models how the metallurgical properties of the resources affect the mass balances and overall throughputs. The results of the project indicate that the current spreadsheet based Mine Plan is not practical since it violates two mass balance constraints within the Combined Treatment Plant. The newly developed system is used to generate a mining schedule that does not violate any constraints while still delivering the same net present value and overall throughput. The system also illustrates that the plant can improve the annual throughput by 18.2% by changing one screen size. The system also illustrates that only two of the five plants add value and supports management‟s recent decision that the production through the other plants should cease. In summary: The newly developed system generates an optimal, practical mine plan in less than a tenth of the time required for the old spreadsheet based model. The new system can also do various what-if scenarios which the previous model could not answer. / AFRIKAANSE OPSOMMING: Die ontginning van diamante in Kimberley het in die vroeë 1870s begin na die ontdekking van verskeie diamanthoudende kimberlietpype. Aanvanklike oopgroefmynbou is later vervang deur ondergrondse metodes soos die myne dieper geword het. Die laaste ondergrondse myne het in 2005 produksie gestaak as gevolg van ekonomiese redes. Die ontginning van hierdie primêre reserwes het gelei tot die ontstaan van verskeie uitskotreserwes (voorheen genoem afvalhope) verspreid oor Kimberley. Hierdie reserwes bevat steeds diamante as gevolg van die historiese oneffektiewe aanlegte. Die reserwes het elkeen egter verskillende geologiese en metallurgiese eienskappe as gevolg van die verskille in die oorspronklike kimberliete en die verskillende herwinningstegnologieë wat in gebruik was toe die uitskotreserwes gegenereer is. Die uitskotreserwes word gemyn deur ‟n vloot grondverskuiwingstoerusting en word afgelewer by een van Kimberley Myne se vyf aanlegte vir diamantherwinning. Elke aanleg is uniek in terme van kapasiteit, tegnologieë in gebruik en algehele effektiwiteit. Hierdie verskille, tesame met die geo-metallurgiese eienskappe van elke reserwe en die vervoerafstand van die reserwe na die aanleg bepaal of die spesifieke reserwe winsgewend deur daardie aanleg geprosesseer kan word. Bogenoemde verskeidenheid van hulpbronne gee aan Kimberley Myne die voordeel van buigsaamheid om die Netto Huidige Waarde (NHW) van die myn te maksimeer. Hierdie buigsaamheid vergroot egter die kompleksiteit om die optimale antwoord te vind. Beplanning word tans met ‟n sigblad gebasseerde invoer – uitvoer model gedoen, maar hierdie model is nie in staat om die reserwes se eienskappe by die aanlegte se parameters aan te pas nie. Hierdie metode genereer dus ‟n plan wat moontlik nie prakties of optimaal is nie. Die model is ook tydrowend en scenario analises is dus baie beperk. Hierdie verslag beskryf die ontwikkeling van ‟n gemengde heeltallige lineêre programmeringsmodel vir die ontwikkeling van ‟n praktiese, optimale produksieplan. Die model is losweg gegrond op ‟n generiese model van Barbaro & Ramani (1986) wat fasiliteit posisionering en aanlegprobleme aanspreek. Die model in hierdie verslag bevat egter ‟n meer gedetailleerde massabalans binne die aanleg en modelleer hoe die metallurgiese eienskappe van die reserwes die massabalanse en die algehele kapasiteite beïnvloed. Die resultate van die projek dui daarop dat die huidige sigblad produksieplan nie prakties is nie aangesien dit twee massabalansbeperkings in die Combined Treatment Plant oorskry. Die nuwe stelsel is gebruik om ‟n produksieskedule te genereer wat nie enige beperkings verbreek nie en wat terselfdertyd die aanvanklike netto huidige waarde en totale produksie ewenaar. Die stelsel wys ook dat die jaarlikse kapasiteit met 18.2% verhoog kan word deur een van die sif-groottes te verander. Die stelsel demonstreer ook dat slegs twee van die vyf aanlegte waarde toevoeg en ondersteun bestuur se onlangse besluit dat die produksie deur die ander aanlegte gestaak behoort te word. Ter samevatting: Die nuwe stelsel genereer ‟n optimale, praktiese produksieplan in minder as ‟n tiende van die tyd benodig vir die ou sigblad model. Die nuwe stelsel kan ook verskeie “Wat sal gebeur indien…” scenario‟s hanteer wat die vorige model nie kon beantwoord nie.
19

Sedimentology of plio-pleistocene gravel barrier deposits in the palaeo-Orange River mouth, Namibia : depositional history and diamond mineralisation

Spaggiari, Renato Igino 19 August 2013 (has links)
The largest known marine diamond placer, the Namibian mega-placer, lies along the Atlantic coast of south-western Africa from the Orange River mouth 1,000 km northwards to the Namibian-Angolan border. The most economically viable portion of the Namibian mega-placer (>75 million carats recovered at >95% gem quality) comprises onshore and offshore marine deposits that are developed within ∼100km of the Orange River outfall. For much of the Cainozoic, this long-lived fluvial system has been the main conduit transporting diamonds from kimberlitic and secondary sources in the cratonic hinterland of southern Africa to the Atlantic shelf that has been neutrally buoyant over this period. Highly energetic marine processes, driven in part, by southerly winds with an attendant northward-directed longshore drift, have generated terminal placers that are preserved both onshore and offshore. This study, through detailed field sedimentological and diamond analyses, investigates the development and mineralisation of gravel barrier deposits within the ancestral Orange River mouth area during a major ∼30 m regional transgression ('30 m Package') in the Late Pliocene. At that time, diamond supply from this fluvial conduit was minimal, yet the corresponding onshore marine deposits to the north of the Orange River mouth were significantly diamond enriched, enabling large-scale alluvial diamond mining to take place for over 75 years. Of the entire coastline of south-western Africa, the most complete accumulation of the '30 m Package' is preserved within the palaeo-Orange River mouth as barrier spit and barrier beach deposits. Arranged vertically and laterally in a 16m thick succession, these are deposits of: (1) intertidal beach, (2) lagoon and washover, (3) tidal inlet and spit recurve and (4) storm-dominated subtidal settings. These were parts of larger barrier features, the bulk of which are preserved as highstand deposits that are diamond-bearing with varying, but generally low grades (<13 stones (diamonds) per hundred tons, spht). Intertidal beach and spit recurve deposits have higher economic grades (12-13 spht) due to the energetic sieving and mobile trapping mechanisms associated with their emplacement. In contrast, the less reworked and more sandy subtidal, tidal inlet and washover deposits have un-economic grades (<2 spht). Despite these low grades, the barrier deposits have the largest average stone (diamond) size (1-2 carats/stone, cts/stn) of the entire Namibian mega-placer, given their proximity to the ancestral Orange River outfall. This study demonstrates that barrier shoreline evolution at the fluvial/marine interface was controlled by: (1) a strong and coarse fluvial sediment supply that sustained shoreline growth on a highly energetic coast, (2) accommodation space facilitating sediment preservation and (3) short-duration, high-frequency sea-level cycles superimposed on the∼30 m regional transgression, promoting hierarchal stacking of progradational deposits. During these sea-level fluctuations, diamonds were 'farmed' from older, shelf sequences in the offshore and driven landward to accumulate in '30 m Package' highstand barrier deposits. In spite of the large supply of diamonds, their retention in these deposits was poor due to an incompetent footwall of ancestral Orange River mouth sediment and the inherent cobble-boulder size of the barrier gravels. Thus the principal process controlling diamond entrapment in these barrier deposits was kinetic sieving in a coarse-grained framework. Consequently, at the marine/fluvial interface and down-drift for ∼5 km, larger diamonds (1-2 cts/stn) were retained in low-grade (<2 spht), coarse-gravel barrier shorelines. Smaller diamonds (mostly < I cts/stn) were rejected into the northward-driven littoral sediments and further size-sorted along ∼95 km of Namibian coast to accumulate in finer, high-grade beach placers (> 100 spht) where bedrock footwall promoted such high concentrations. The gravel-dominated palaeo-Orange River mouth is considered to be the ' heart' of the Namibian mega-placer, controlling sediment and diamond supply to the littoral zone further north. Although coarse gravel is retained at the river mouth, the incompetence of this highly energetic setting to trap diamonds renders it sub-economic. This ineffectiveness at the fluvial/marine interface is thus fundamental in enriching the coastal tract farther down-drift and developing highly economic coastal placers along the Atlantic coast of south-western Africa. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in
20

Worker's perception regarding the introduction of technology at Chiadzwa diamonds mines in Zimbabwe

Chimeri, Munyaradzi Leo 15 February 2016 (has links)
Department of Sociology / MA (Industrial Sociology)

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