Dissertations / Theses: 'Diamond mines and mining – Namibia'

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Rau, Grant. "A geological evaluation of marine diamond placer deposits on the central Namibian inner shelf : a case study of the Hottentot Bay area." Thesis, Rhodes University, 2004. http://hdl.handle.net/10962/d1007554.

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This study focusses on the marine diamond placers within Exclusive Prospecting Licence 1950 and Mining Licence 103a, located northwest of the north-facing Hottentot Bay which is 60 km north of Lüderitz, along the central Namibian coastline. The thesis follows the natural geological evolution of the marine placer deposit from primary source, through alluvial and/or glacial transportation, concentration along the coastline by wave, aeolian and alluvial/sheet-wash processes and finally marine diamond placer preservation. All of these processes are reviewed as they are important in understanding of the evolution marine placer deposits. The poly-cyclic role of coastal aeolian, alluvial, and marine processes, in marine placer enrichment is shown to be particularly important in considered target identification and prioritisation. A detailed bathymetric, sonographic and seismic interpretation, is an integral part of diamond placer exploration, and was used to examine and describe surficial and sub-bottom characteristics within the study area. Marine placers are formed along palaeo-strandlines during periods of marine transgression and regression and are therefore fundamental in marine placer exploration. A detailed bathymetry map, compiled for this study, of the area between Lüderitz Bay and Clara Hill, provides the foundation for a detailed terrace level investigation. Regionally, twelve well-developed stillstand levels are identified, nine of which fall into the study area. These interpretations are compared with global eustatic as well as terrace and resource/reserve levels in the Lüderitz area and are found to correlate well. Sediment dynamic studies involve the use of accredited application software for wave refraction modelling, to determine the wave angle and orbital wave velocity at the seabed. Bedload velocities, required to move diamonds of specific sizes, can be empirically determined and therefore areas of diamond entrainment and deposition can be modelled and target features delineated and prioritised. These detailed interpretations provide a sound platform for evaluating diamond placer process models in the study area. By integrating both previously published and newly formulated ideas, a revised, holistic model for the formation of marine diamond placer deposits in central Namibian is postulated. The proposed model is tested by comparing it to the lateral distribution of presently defined resource/reserve areas in the Lüderitz area and shows a close correlation with most of these enriched deposits. Based on this model, a matrix for the delineation and prioritisation of marine placer deposits is developed and the best target features within the study area are identified.
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De, Almeida Louise. "The effect of sewage effluent from De Beers marine diamond mining operations on the expression of cytochrome P450 (CYP1A) and vitellogenin (vtg)." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1009440.

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Sewage effluents disposed into the marine environment from De Beers Marine Namibia diamond mining vessels have the potential to cause endocrine disruptive effects in marine organisms. Endocrine disruption refers to the alteration of the normal functioning of the endocrine system and various chemicals have the ability to mimic hormones, effecting endogenous hormone synthesis, transport, receptor interaction and intracellular signaling. The potential endocrine disruptive effects, caused by the release of different types of sewage effluents into the ocean, on fish species is a concern due to the commercial importance of fish species found in the mining area e.g. hake, sole, horse mackerel. Increased awareness of marine environmental degradation due to the presence of chemical contaminants has resulted in research being done on early warning systems, in the form of biomarkers. Cytochrome P450 monooxygenase 1A (CYP1A) and vitellogenin (vtg) are important proteins found in fish liver and blood, that have been used as biomarkers for the detection of pollutants in fish. CYP1A is a subfamily of the P450 superfamily of enzymes and catalyzes the oxidation, hydrolysis and reduction of exogenous and endogenous compounds (phase I reactions) and thus has the capacity to regulate the metabolism of several organic contaminants. CYP1A expression is altered by exposure to planar xenobiotic compounds e.g. polyaromatic hydrocarbons. Vtg is an important precursor for egg yolk proteins and plays a role in the growth and development of an oocyte. Expression of this protein is altered upon exposure to estrogenic compounds. The aim of this project was to isolate CYP1A from fish liver by differential centrifugation and optimize conditions for the CYP1A-mediated ethoxyresorufin-Odeethylase (EROD) assay and western blot analysis (to assess CYP1A expression). Another aim of this study was to evaluate the potential effects of biologically disruptive chemicals from sewage effluents, discharged into the marine environment, on the expression of CYP1A in two species of hake, Merluccius capensis and M. paradoxus (Cape hake). CYP1A in Cape hake is approximately a 60 kDa protein and the highest EROD activity was detected in the microsomal fraction after differential centrifugation. Optimal EROD assay conditions were observed at pH 7.5, a temperature of 25 °C, 10 μl of sample and a reaction time of 30 seconds. Enzyme stability assays indicated a drastic decrease in enzyme activity after 30 seconds. The EROD assay was not NADPH dependent but was limited by NADPH supply, with an increase of 300% in EROD activity being observed with the addition of 0.1 M exogenous NADPH. The addition of dicumarol (40 μM), a phase II enzyme inhibitor, showed a 232% increase in EROD activity. This is because dicumarol inhibited enzymes with the capacity to metabolize the product (resorufin) of the EROD reaction. With regard to western blot analysis, the optimal primary (rabbit antifish CYP1A peptide) and secondary (anti-mouse/rabbit antibody-horseradish peroxidase conjugate (POD)) antibody dilutions were determined to be 1:1000 and 1:5000, respectively. The comparison of CYP1A expression in Cape hake samples from De Beers Marine mining area and reference sites showed higher EROD activity (16.29 ± 0.91 pmol/min) in fish samples from the mining area in comparison to the reference site (10.42 ± 2.65 pmol/min). Western blot analysis was in agreement with the EROD assay results and a higher CYP1A expression was observed in fish from the mining sites. The increased CYP1A expression observed in fish from the mining area is not definitively an indication of a pollutant effect in the environment, as several environmental and biological factors (e.g. photoperiod and age) must also be considered before reaching this conclusion. Another aim of this study was to purify vtg from Cape hake blood samples. Cape hake vtg was purified from fish plasma by selective precipitation with MgCl2 and EDTA. Precipitated sample was subjected to anion exchange chromatography using fast protein liquid chromatography (FPLC). Vtg eluted as two broad peaks and had a molecular weight above 200 kDa. SDS-PAGE analysis also resolved smaller molecular weight proteins below 70 kDa, which were thought to be vitellogenin cleavage proteins, lipovitellin and phosphovitins. Western blot analysis was performed; however, it did not produce any conclusive results. The purification of vtg enables further studies in characterizing this protein and developing assay aimed at detecting estrogenic pollutants in the marine environment

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Spaggiari, Renato Igino. "Sedimentology of plio-pleistocene gravel barrier deposits in the palaeo-Orange River mouth, Namibia : depositional history and diamond mineralisation." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1004636.

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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.
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Maritz, Liezl. "Ecological role of mining ponds in Southern Coastal Mines, Namibia." Master's thesis, Faculty of Science, 2021. http://hdl.handle.net/11427/32833.

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Targeting marine diamondiferous deposits along the south-western Namibian coastline has involved the construction of seawall berms to advance the coastline and permit mining in previously subtidal areas. Large areas are mined out to bedrock level by the removal of overburden (sand and gravel), and after mining is complete, areas behind the seawalls fill with seawater, creating a series of coastal marine ponds that have the potential to function as saline wetlands corresponding to closed estuaries. The study site lies north of the Orange River mouth, within the Tsau//Khaeb (Sperrgebiet) National Park, to which the public has restricted access due to diamond mining in the area. Consequently, there is a focus on biodiversity conservation and the overall objective of this thesis was to determine the ecological value of the mining ponds by investigating whether they harbour sufficient biodiversity to qualify as a viable alternative ecological habitat, rather than restoring them to their original state as backfilled, revegetated dune areas. The study area, approximately 75 kilometres in length, was divided into north, middle and south sections, according to the age and status of mining activities, and I first assessed whether ponds in these three areas differed in their physical properties (Chapter 1). To determine whether the ponds serve as a useful ecological role worth preserving, I then investigated the diversity and amount of saltmarsh vegetation (Chapter 2), bird species (Chapter 3) and fish (Chapter 4) currently benefiting from these mining ponds. Ponds in the north are older and hypersaline whereas the south and middle ponds are younger and closely approach physical conditions in the sea. Diurnal fluctuations in oxygen concentration took place, but oxygen levels never dropped below 80% and were thus not limiting. After about 15 years, ponds developed salinities in excess of 80‰, which is likely to set limits on their ecological viability. Most ponds supported saltmarshes, but only a single species, Salicornia natalensis, grew around them. Its abundance was greatest around old ponds, but its health decreased with salinity. Wind emerged as a likely means of dispersal among ponds. The ponds supported a rich avifauna, averaging 11028 birds per count for all ponds combined; 36 species were recorded, ten being endemics, and five being listed in Namibia's Red Data Book. Numbers were highest for ponds that were being ‘dewatered' to remove water prior to mining, as this exposed a rich benthic epifaunal source of food. Blacknecked Grebe, Cape Cormorant, Greater and Lesser Flamingos, Kelp Gull and Common Tern were the most abundant birds. Salinity did not limit bird numbers or diversity, so the northern high-salinity ponds may continue to serve as bird habitat for periods of time much greater than the 15 years after which they become hypersaline. In comparison with nine other wetlands in the region, the ponds had great numbers, diversity, densities, and numbers of threatened species than about half of these wetlands, many of which are considered Important Bird Areas (IBAs). In many cases, they also supported more species that had numbers in excess of 1% of the southern African population than these IBAs. Only two species of fish commonly occurred in the ponds, the west coast steenbras Lithognathus auratus and the southern mullet Chelon richardsonii, although small numbers of two other marine species were recorded. The diversity of marine fish was thus low, even by the impoverished standards of west-coast estuaries. Unexpectedly, there were no significant differences between the ichthyofauna of ponds in the north, middle and south, nor was there any relationship between total fish numbers and salinity. Body condition of steenbras was lowest in the hypersaline north ponds, and their stomach contents contained a low diversity of food items there. The presence of recruits and the range of gonadal states suggested that both species bred in the ponds. Steenbras proved to be protandrous, with females dominating larger size classes. Growth rates of both species were faster in the ponds than in the adjacent sea, and mullet achieved substantially greater sizes in ponds. Thus, the ponds do serve as viable ecosystems, albeit with a limited range of saltmarsh and fish species, and support an impressively diverse avifauna. Their long-term viability will, however, become limited by rising salinity as their age increases.

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Sihlahla, Kyllikki Taina Niita Ndangi. "Perceptions on the impact of strikes on productivity at selected mines in the mining sector of Namibia." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2081.

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Thesis (MTech (Human Resource Management))--Cape Peninsula University of Technology, 2016.
The mining sector has been the backbone of the Namibian economy since Namibia attained its independence. However, the disruptive nature of the numerous strikes that are experienced in the mining sector has prompted this study that explores the perceptions held by different stakeholders on the impact of strikes on the productivity of three selected mines in Namibia. The selected mines are Langer Heinrich mine, Navachab Gold mine and Skorpion Zinc mine. Labour disputes in Namibia’s mining sector have a long history dating back to the colonial era. A myriad of factors that include, amongst others, poor remuneration, unfair labour practices, poor social and housing amenities, perceived discrimination and harsh working conditions are major triggers for mining sector strikes. Strikes are mostly conducted by employees when they fail to amicably resolve a labour dispute with their employers. Employees are normally perceived as the backbone of any organisation. Conflicts, however, are part of human nature and can only be avoided, in most cases, if people are conscious of the consequences of their actions and reactions, hence, the need to explore the perceptions of stakeholders on the impact of strikes on the productivity of the selected mines. Human perceptions are dynamic in nature. Irrespective of this fact, in this research questionnaires were administered to obtain the perceptions of mine management, miners and trade union members on the effects of strikes on the productivity of the three selected mines. A different questionnaire was designed to gather the views of the Ministry of Labour and Social Welfare (MLSW) officials since in most cases they are involved in conciliating the disputing parties. Generally, strikes have negative impacts not only on the organisation concerned, but also on the Namibian economy at large. The mines selected for this research are situated in the Khomas, Erongo and Karas regions of Namibia. Most mining companies in Namibia are located in Erongo and Karas, whereas Windhoek, which is in the Khomas region, mainly houses some of these mines headquarters. A five-point Likert scale was used to gather data in the survey. Specialised software called Statistical Program for Social Scientists (SPSS) was then used to analyse the data. Although the results indicate that in most cases the striking parties are aware of the adverse effects of strikes on productivity of the mines, they still opt to use strikes as a bargaining weapon. Since conflicts are always bound to arise where two or more parties interact, this study recommends that there should always be a conciliator who tries to amicably resolve disputes by sensitising each party on the consequences of strikes. The study also recommends a model which emphasises the need to thoroughly inform the mineworkers and the mine management on the ripple effects of strikes and on the need to achieve a win-win situation for all the parties that are involved in a conflict. The model emphasises that although the employees and the employers can individually and separately approach the official, which is the MLSW, such official should always provide open feedback to the feuding parties through a tripartite negotiation forum, otherwise any other type of covert feedback may be misinterpreted as bias by one of the feuding parties. The model further explains that at all times direct negotiations between employees and their employers must be kept open, as it is possible that agreements that can reduce strike action may be reached without necessarily engaging a third party.

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Spiegel, Samuel Jason. "Understanding operation Chikorokoza Chapera : the political ecology of 'formalising' Zimbabwe's gold and diamond mining sectors, 2006-2012." Thesis, University of Cambridge, 2014. https://www.repository.cam.ac.uk/handle/1810/283949.

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Walraven, Felix Caspar. "The geology and alteration-mineralisation of the Gamigab Tin Prospect, Damaraland, Namibia." Thesis, Rhodes University, 1990. http://hdl.handle.net/10962/d1005568.

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The stratigraphy at the Gamigab Sn prospect consists of two mainly schistose units separated by a thick marble unit which have been assigned to the Orusewa, the Karibib and the Kuiseb Formations respectively. Four phases of folding affected the lithologies with the south-south-west trending F2 folds defining the main structures in the region. The area underwent low grades of metamorphism. Temperatures were in the range 420° to 500°C and pressures less than 2 kbars. The effects of contact metamorphism are seen in the south-east and south-west. Regional metamorphism outlasted the deformation and contact metamorphism started late during deformation. Two Karoo-age intrusions penetrated the metasediments north of the mineralisation. One is an altered porphyry plug and the other is a weathered dolerite plug, the latter containing xenoliths of undeformed Karoo sediments. Cassiterite is hosted within east-west trending quartz veins that cross-cut previously altered schistose country rocks. The alteration types include sericitisation, tourmalinisation, carbonatisation and ferruginisation. Preliminary Rb/Sr dating on muscovite from the alteration zone suggests an age of 509 ± 11 Ma. Breccias of probable hydrothermal origin are spatially associated with the mineralisation. These hydraulic breccias occur in antiformal structures within the marble and developed in response to a sudden pressure release due to a build up of fluids at the contact between the schistose Orusewa and carbonate Karibib Formations.

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Louw, Alet. "The environmental regulation of uranium mines in Namibia : a project life cycle analysis / Louw A." Thesis, North-West University, 2012. http://hdl.handle.net/10394/7600.

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Uranium exploration and mining activities in Namibia have increased rapidly since 2003, which increase not only poses a significant impact on the country’s economy, but also on its unique and pristine natural environment. The nature and extent of the environmental impacts associated with uranium mining requires a sound environmental law and policy framework that regulates uranium activities, impacts and aspects during each phase of the project life cycle of a uranium mine. It also requires of authorities to establish and enhance environmental protection and sustainability during uranium mining operations and to ensure that all environmental impacts that inevitably occur as a result of uranium mining activities are addressed in a holistic and integrated manner during each phase of the project life cycle of a uranium mine. In order to do this the country must develop and maintain an efficient and effective environmental governance regime. Namibia’s environmental law and policy framework that regulates uranium mining does not cover the entire PLC of uranium mining. It is vital that the current loops in the country’s existing environmental regulatory framework be closed and that an efficient and effective environmental governance regime, as envisaged in this study, be established. This will enable the administering agents to actively promote and maintain the welfare of the people, ecosystems, essential ecological processes and the biodiversity of Namibia, as well as the utilisation of living natural resources on a sustainable basis to the benefit of all Namibians, both present and future, as pledged in the Namibian Constitution.
Thesis (LL.M. (Environmental law))--North-West University, Potchefstroom Campus, 2012.

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Mabhudu, Mark. "A comparative analysis of leadership and management at Jwaneng Diamond Mine /." Link to the Internet, 2008. http://etd.sun.ac.za/jspui/handle/10019/1925.

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Sitoka, Stefanus. "Exploration status for oxide and sulphide zinc ores at Skorpion Zinc Mine, Namibia." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1018204.

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The thesis is inspired by recent interests in oxide zinc ores caused by new developments in the technology of hydrometallurgy. The improved techniques turned the non-sulphide zinc ores in to attractive exploration targets due to a number of advantages such as low metal recovery costs and favorable environmental aspects such as the obvious absence of sulfur (Large, 2001). Historically extraction of zinc metal from oxide ores was not possible until recently. The metallurgical complexity resulted in a lack of interest and hence some economic oxide zinc ores might have been missed by conventional exploration techniques. The study presents a review of exploration status at Skorpion mine based on different exploration techniques and their application to sulphide and oxide zinc ore exploration. The challenge facing the mineral exploration industry today is the inability to detect mineral deposits under cover. Therefore a key to successful exploration program lies in the selection of the right exploration technique. Important parameters that should be highlighted in the exploration methodology are the geological situation of an area, equipment applicability and effectiveness, survey limitation, equipment mobilization and the safety aspects involved. The aim of this thesis is to provide a general guideline for sulphide and non-sulphide zinc ore exploration on the Skorpion area and other similar geological environments. Geochemical surveys appears to be more complimentary in exploration of non-sulphide zinc exploration. Although geochemical techniques are preferred, it is equally important to choose the right soil horizon. Furthermore, sample media may mean the difference between success and failure in geochemical exploration of non-sulphide zinc mineralization, due to high mobility of zinc in the surficial environment. On cost comparison, surface geochemical surveys programs are more cost effective except for litho-geochemical sampling which are commonly carried out through subsurface drilling. Geophysical techniques have limited application in exploration of non-sulphide zinc mineralization due to a lack of major physical properties (e.g., magnetic and electrical properties) in non-sulphides unlike their sulphide counterparts. However geophysical methods are commendable in delineating massive and disseminated sulphides mainly if they are associated with major Fe minerals (pyrrhotite or magnetite). In addition, geophysical techniques may be effective in mapping of subsurface primary and secondary structures such as basin faults which might have acted as pathways for metal-rich fluids. Terms non-sulphide and oxide zinc mineralization are used interchangeably throughout the thesis. Recommendations on regional and local target generation are presented in the thesis to give some basic guide lines on target generation strategies. The most important conclusion reached in this study is that, success in exploration for non-sulphide or sulphide zinc mineralization might be enhanced through the integrated exploration methodology.

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Doohan, Kim Elizabeth. ""Making things come good" Aborigines and miners at Argyle /." Doctoral thesis, Australia : Macquarie University, 2007. http://hdl.handle.net/1959.14/145.

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Thesis (PhD) -- Macquarie University, Division of Environmental and Life Sciences, Department of Human Geography, 2007.
"November 2006".
Bibliography: p. 352-398.
Mode of access: World Wide Web.
xvi, 399 p. ill., maps

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Nakathingo, Phillemon Kashiimbi. "Assessing knowledge, attitude and practices of male condom use among male employees fifty years and older at a diamond mining company in Namibia." Thesis, University of the Western Cape, 2012. http://hdl.handle.net/11394/4639.

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Magister Public Health - MPH
Background: The HIV / AIDS pandemic have been characterized as the greatest natural challenge ever to confront humanity and one of the great moral causes of our time (World Bank, 2007). Although, the HIV and AIDS pandemic is a global problem, some regions of the world, notably sub-Saharan Africa are hardly hit by the pandemic. Namibia is one of the sub-Saharan African countries which are badly affected by the HIV and AIDS pandemic. It is estimated that about 360 000 Namibians were infected with HIV by 2010. This translates to a national HIV prevalence of (18.8%). The National HIV and AIDS Response Department has designed various interventions and strategies to curb the spread of the HIV. Promotion of male condoms promotion is one of the key strategies being advocated. If used consistently and correctly, male condoms are regarded as an effective preventive tool of HIV transmission. However, changing individual’s sexual behaviors and lifestyle to make condom use part of their sexual life seems to be the challenge. In Namibia most of the research in the area of HIV and AIDS were done among the youth and population aged between 15 – 49 years. Hence, this study looks at older men as a neglected population. Aim: The aim of the current study was to assess knowledge, attitudes and practices of condom use among male employees age 50 (fifty) years and older at a mining company in Southern Namibia. Methodology: A descriptive, cross-sectional survey utilizing quantitative research approach was applied. Data was collected through face-to-face interviewing male employees, age fifty years and older, while at work at the Mine Area 1 (MA1). Data was captured in excel and imported into SPSS version 16.0. Chi-square test was used to determine the association between KAP variables and the socio-demographic characteristics of the respondents. The level of statistical significance was set at 0.05. Results: Among 105 respondents (males, mean age 54.5 years), more than half lived in the singe sex male hostels. Knowledge about condom use was good but there remained a significant number of the respondents whose knowledge was insufficient. A high percentage of the respondents suggested that HIV positive individuals should always use condom every time they have sexual intercourse. Conclusion: This study showed that respondents are not at a high risk of contracting HIV infection due to lack of knowledge on condom use though some of them possessed insufficient knowledge. Thus, to minimize the likelihood of HIV infection targeted interventions including peer education programmes were suggested, and working with the community in the area. Moreover, a more comprehensive knowledge attitude and practice study among mine employees from various sections of the mine would be beneficial to identify the level of risk within the total employee population.

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Henderson, John C. "The Crater of Diamonds: A History of the Pike County, Arkansas, Diamond Field, 1906-1972." Thesis, University of North Texas, 2002. https://digital.library.unt.edu/ark:/67531/metadc3088/.

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The first diamond mine in North America was discovered in 1906 when John W. Huddleston found two diamonds on his farm just south of Murfreesboro in Pike County, Arkansas. Experts soon confirmed that the diamond-bearing formation on which Huddleston made his discovery was the second largest of its kind and represented 25 percent of all known diamond-bearing areas in the world. Discovery of the field generated nearly a half century of speculative activity by men trying to demonstrate and exploit its commercial viability. The field, however, lacked the necessary richness for successful commercial ventures, and mining was eventually replaced in the early 1950s by tourist attractions that operated successfully until 1972. At that time the State of Arkansas purchased the field and converted it to a state park. Thus this work tell the rich and complicated story of America'a once and only diamond field, analyzes the reasons for the repeated failures of efforts to make it commercially viable, and explains how it eventually succeeded as a tourist venture.

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Maletzky, Erich. "The effects of oxygen deficiency, hydrogen sulphide and turbidity on the rock lobster, Jasus lalandii : implications for diamond dredge-mining in Namibia." Master's thesis, University of Cape Town, 2007. http://hdl.handle.net/11427/6128.

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Includes abstract.
Includes bibliographical references (leaves 131-144).
A study was initiated by the Environmental Section of the De Beers Marine Namibia group as part of a pre-feasibility study for a new dredger (a Trailing Suction Hopper Dredger) to be employed for offshore diamond mining along the Namibian south coast. The aims of this study were to assess (a) the potential mining-induced impacts on oxygen and turbidity, and (b) the behavioural responses of the rock lobster Jasus lalandii, to decreased oxygen, elevated hydrogen sulphide and turbidity. For the latter objective, laboratory-based experiments were designed in which juvenile lobsters were exposed to various levels of hypoxia and increased hydrogen sulphide and suspended sediment levels to determine the impacts these stressors may have on the behavioural responses of lobsters.

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Du, Toit Jeremias Cornelius. "A decision support system to optimise the available resources at Kimberley Mines." Thesis, Stellenbosch : Stellenbosch University, 2007. http://hdl.handle.net/10019.1/50673.

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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.

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Van, Zuydam Henk Johan. "The alluvial diamond industry a critical analysis of the capital cost allowances /." Diss., Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-06152009-150607/.

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Kalenga, Fernand Kasongo. "Liaisons entre l'agriculture paysanne et l'exploitation artisanale du diamant dans la province du Kasai-Oriental en République démocratique du Congo /." Berlin : Köster, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015824279&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Lawrence, Paul Gilbert. "Class, colour consciousness and the search for identity : blacks at the Kimberley diamond diggings, 1867-1893." Master's thesis, University of Cape Town, 1994. http://hdl.handle.net/11427/21506.

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Bibliography: pages 168-176.
The discovery of diamonds in the Kimberley area was to have far reaching consequences, not only for the region but the entire sub-continent. In addition to the hundreds of individual diggers, mainly white, who converged on this arid corner of southern Africa, there appeared also, in a remarkably short time, a complete infrastructure of urban facilities to serve their needs. Perhaps the most unique component of the otherwise colonial population was the massive influx of migrant Africans in response to the insatiable labour demands of the diamond mines. We examine the interplay of racial attitudes and conflicts and the ambiguous position of the black elites in the diverse groups of 'colonial' or 'civilised' Africans, 'Cape Coloureds', Muslims and Indians who came to Kimberley to seek their fortune. It is our contention that it was this ambiguity which was to provide a spur to black political activity. We closely consult contemporary accounts, official documentation and local newspapers, all of which faithfully record the ebb and flow of the state of racial relations. Never a typical microcosm of colonial urban society because of the extraneous factor of economic competition for limited employment and resources, social relationships in Kimberley gradually changed until the essential confrontation was not between colonials and the rest, but rather more specifically between blacks and whites. While the early history of Kimberley was marked by the virulent racism of white· diggers resisting black competition, the ensuing years were to witness a more tranquil period of racial co-existence. This tranquillity proved to be only the calm before the storm. We show how a series of crises strained relations between blacks and whites to breaking point. The failed rebellion by indigenous blacks, the smallpox epidemic during which the Muslim community incurred the wrath of white public opinion by failing to adopt western preventative measures, a revolt - the Black Flag Revolt- by militant white diggers and the effects of the new recruitment policies of the mining companies in the 1880s, which opened jobs to cheap black workers, all resulted in an increasing polarisation of race relations in Kimberley. We argue that where before official documents and newspapers had shown a class discrimination directed against migrant African labourers, this changed over time to become a negative portrayal of blacks in general. The effect of the emergence of this negative stereotype was to separate whites and blacks in many facets of life in the mining centre.

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Fuls, H. F. "Matrix management in the new millennium : the skorpion zinc experience." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/4869.

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Thesis (MBA (Business Management))--University of Stellenbosch, 2006.
ENGLISH ABSTRACT: Globalisation and increased communication flow in the world has increased competition tremendously over the last decade. For organisations to stay ahead of their competition it became essential to adapt quickly. Flexible low cost organisations will become leaders in the industry. Collaboration and teamwork in organisations, especially across functions, could maximise flexibility and productivity. Matrix structures were introduced in the sixties by multinational companies and by the early Seventies many other companies followed suit with mixed success. Academic interest faded after the mid Eighties. The challenge of continual, fast growing organisations is opening a debate for project management and cross-functional structures as teamwork and effective collaboration between functional departments become key to success. This study will focus on application of matrix management structures in the new millennium and project management principles applied by a literature search. The best practice model is compiled with specific application to Skorpion Zinc. Skorpion Zinc is a newly commissioned zinc mine and refinery, applying new technology to produce Special High Grade zinc. Application of this model is verified by personnel from the organisation by means of a questionnaire. Research indicates that most project orientated organisations prefer and use matrix management structures to manage their business. Successes and challenges related to crossfunctional structures are similar to those experienced in the Eighties. Implementation and management of the structure is the key to success. Selecting the correct type of matrix structure that will best support the business is vital. The study reveals that the Weak Matrix Management structure applied in the Refinery Department will enhance personnel management, project management and enable optimal utilisation of resources. In addition to the implementation of the structure focus is required in improvement of project management principles. Enabling factors to the Weak Matrix Structure that needs to be encouraged is a cooperative culture, teamwork, open and effective communication. Skorpion Zinc can use their strength of trust within departments and expand this to an interdepartmental trust. It is concluded that the study has identified the latest trends and success factors related to matrix management structures. Best practice suitable to Skorpion Zinc has been identified and verified. By applying this knowledge, the organisation can look forward to producing zinc cost effectively with a contented workforce, thus becoming a world leader in its class.
AFRIKAANSE OPSOMMING: Internasionalisering en toenemende kommunikasie vloei regoor die wereld het kompetisie geweldig laat toeneem oor die laaste dekade. Vir organisasies om kompeterend te bly het dit al belangriker geword om vinnig te kan aanpas by veranderende omstandighede. Aanpasbare, lae koste besighede sal leiers in die industrie word. Spanwerk en samewerking in organisasies, veral tussen funksionele departemente sal lei tot aanpasbaarheid van die maatskappy en produktiwiteit van werknemers. Matriks strukture was in die sestiger jare bekend gestel deur internasionale maatskappye wie se voorbeeld gevolg was deur ander maatskappye in die vroeer sewentiger jare met gemengde sukses. Akademiese belangstelling het gekwyn na die later tagtiger jare. Uitdagings van vinnig groeiende, dinamiese organisasies het opnuut debat rondom projek bestuur en matriks strukture laat opvlam as gevolg van sukses wat bereik word deur samewerking tussen funksionele departemente. Fokus van die literatuur navorsing studie sal val op die jongste toepassing van matriks organisasie strukture en projek bestuur beginsels. 'n Model van beste praktyke van toepassing op Skorpion Zinc is saamgestel. Skorpion Zinc is 'n jong sink myn en raffinadery, onlangs in gebruik gestel, wat nuutste tegnologie aanwend om Spesiale Hoe Graad sink te ontgin en produseer. Werknemers het die toepaslikheid van die model bevestig deur middel van 'n vraelys. Navorsing dui aan dat meeste projek ge-orienteerde organisasies vierkies en wend matriks strukture aan om hul besighede te bestuur. Vandag se suksesse en uitdagings verwant aan matriks strukture is baie eenders as wat ondervind was in die tagtiger jare. Implementering en bestuur van die strukture is die sleutel tot sukses. Die keuse van die matriks struktuur wat die onderneming sal ondersteun is van kardinale belang. Navorsing dui daarop dat die Afgewaterde Matriks struktuur, soos toegepas in die Produksie Afdeling, personeel bestuur, projek bestuur en optimale benutting van menslike hulpbronne sal bevorder. Dit is belangrik dat aandag toegespits word op verbetering van projek bestuur beginsels tesame met implementering van die struktuur. 'n Samewerkende kultuur, spanwerk, effektiewe en op die man af kommunikasie is ondersteunende faktore vir matriks strukture wat bevorder moet word. Die gevolgtrekking kan gemaak word dat die navorsing beste gebruike en sukses faktore van matriks bestuur uitlig. Gebruike van toepassing op Skorpion Zinc is geidentifiseer en bevestig. Deur die kennis toe te pas kan die maatskappy uitsien daarna om 'n wereld leier op sy gebied te word met lae koste sink produksie en 'n bevredigde arbeidsmag.

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Bell, Maria Aletta. "Monitoring rehabilitation success using remotely sensed vegetation indices at Navachab Gold Mine, Namibia." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97888.

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Thesis (MA)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Remote sensing and vegetation indices were evaluated for its usefulness to monitor the success of the rehabilitation programme of the decommissioned tailings storage facility (TSF1) of the Navachab Gold Mine, Karibib, Namibia. The study aimed to objectively illustrate the rehabilitation progression from tailings (baseline) to soil (capping) and vegetation (planted as well as natural). Baseline data sets of 2004 and 2005 were compared with imagery of 2009, 2010 and 2011. All the images were subjected to panchromatic sharpening using the subtractive resolution merge (SRM) method before georegistration. As no recent accurate topographical maps were available of the study area, the May 2010 image was used as a reference image. All other images were georegistered to this image. A number of vegetation indices (VIs) were evaluated. The results showed that the normalised difference vegetation index (NDVI) and the transformed vegetation index (TVI) provided the most promising results. Although the difference vegetation index (DVI) and enhanced vegetation index (EVI) distinguished the vegetation, rock, and soil classes, it was not as successful as the other VIs in classifying the rain water pond. TVI and NDVI were further evaluated for their efficacy in detecting changes. This was done by generating a series of change images and by qualitatively comparing them to false colour images of the same period. Both the NDVI and TVI delivered good results, but it was found that the TVI is more successful when water is present in the images. The research concludes that change analyses based on the TVI is an effective method for monitoring mine rehabilitation programmes.
AFRIKAANSE OPSOMMING: Afstandswaarneming en plantegroei-indekse is ge-evalueer vir die gebruikswaarde daarvan om sukses van die rehabilitasieprogram vir die geslote slykdam of tailings storage facility (TSF1) van die Navachab Goudmyn, Karibib, Namibië vas te stel. Die studie se doelwit was om die progressie in die rehabilitasie van slyk (basislyn) na grond (dekmateriaal) en plantegroei (aangeplant en natuurlik) te illustreer. Basislyndatastelle 2004 en 2005 is vergelyk met 2009, 2010, en 2011 beelde. Al die beelde is panchromaties verskerp deur die subtractive resolution merge (RSM) metode voor georegistrasie uit te voer. Aangesien geen onlangse, akkurate topografiese kaarte van die studiegebied beskikbaar was nie, is die beeld vir Mei 2010 as ‘n verwysingsbeeld gebruik. Al die ander beelde is op die laasgenoemde beeld gegeoregistreer. Die resultate het gewys dat die normalised difference vegetation index (NDVI) en die transformed vegetation index (TVI) die mees belowende resultate lewer. Al het die difference vegetation index (DVI) en enhanced vegetation index (EVI) goed onderskei tussen plantegroeiklasse en grond- en gesteentesklasse was dit nie so suksesvol met die klassifikasie van die reënwaterpoel nie. TVI en NDVI is verder geëvalueer vir effektiwiteit om verandering waar te neem. Dit is gedoen deur ‘n reeks van veranderingsbeelde te skep en dit dan kwalitatief met die valskleur-beelde vir dieselfde tydperk te vergelyk. Beide die NDVI en TVI het goeie resultate gelewer, maar die TVI was meer suksesvol om beelde met water te klassifiseer. Die navorsing lei tot die gevolgtrekking dat veranderingsanalises met die TVI ‘n effektiewe metode vir die monitoring van rehabilitasie programme is.

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Mota, Isadora Moura. "O 'vulcão' negro Chapada : rebelião escrava nos sertões diamantinos (Minas Gerais, 1864)." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/281885.

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Orientador: Robert Slenes
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciencias Humanas
Made available in DSpace on 2018-08-05T10:38:17Z (GMT). No. of bitstreams: 1 Mota_IsadoraMoura_M.pdf: 13645568 bytes, checksum: e0417b7bc74ffa0113821a3783fa5e34 (MD5) Previous issue date: 2005
Resumo: Esta dissertação conta a história da rebelião escrava do Serro, movimento que reuniu mais de quatrocentos rebeldes em Minas Gerais, no mês de outubro de 1864. Cientes dos projetos emancipacionistas em debate no Parlamento nacional e da Guerra Civil nos Estados Unidos, escravos das lavras de diamantes, fazendas e cidades do Serro e Diamantina planejaram uma "guerra contra os brancos" para obter sua liberdade. Eles contavam com o apoio de comunidades quilombolas e homens forros. Através da análise desta revolta, esperamos trazer à tona as culturas e experiências da escravidão no nordeste mineiro, assim como suas relações com o cenário político da década de 1860
Abstract: This dissertation tells the story of the Serro slave rebellion, which gathered more than four hundred rebels in Minas Gerais, during the month of October, 1864. Aware of the emancipationist projects debated in Brazil's National Assembly and the U.S. Civil War, slaves from the diamond mines, farms and the cities of Serro and Diamantina planned a "war against the whites" in order to obtain their freedom. They expected to be supported by maroon communities and black freedmen. Through the analysis of this revolt, we wish to reveal the slave cultures and experiences in the mineiro northeast, as well as its relationship with the political landscape of the 1860
Mestrado
Historia Social
Mestre em História

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Yoboue, Koffi Kouadio Michel. "La question de la remédiation environnementale résultant de l'exploitation artisanale, à petite échelle du diamant : cas de l'Union du fleuve Mano." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30013/document.

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L'exploitation artisanale, à petite échelle du diamant se pratique dans tous les pays de l'Union du Fleuve Mano (Côte d'Ivoire, Guinée, Libéria et Sierra Leone) de façon rudimentaire et parfois de façon informelle. L'exploitation minière artisanale du diamant offre cependant une importante stratégie de subsistance aux communautés locales car elle constitue l'activité principale de la plupart des travailleurs mineurs dans l'Union du Fleuve Mano (UFM). Il ressort de nos études de terrain et des enquêtes auprès des artisans mineurs que ce type d'exploitation minière a des impacts directs sur les galeries forestières, le sol et les cours d'eau. De plus, nous montrons que la réduction des impacts environnementaux engendrés par l'exploitation artisanale, à petite échelle de diamants n'est pas ressentie comme une nécessité ni comme une préoccupation majeure au sein de la communauté des artisans mineurs. Il y a souvent de la part des artisans mineurs un manque de compréhension des problèmes environnementaux et une insuffisante capacité à y faire face, comme le révèle notre étude menée sur trois sites Bobi, Toubabouko et Tortiya en Côte d'Ivoire. Les aires protégées au titre de leurs biodiversités, qui revêtent une importance écologique et socioéconomique majeure pour les populations des pays de la région de l'UFM, subissent malheureusement des pressions importantes du fait de cette exploitation minière artisanale du diamant. D'autant que bien souvent la population des artisans mineurs des sites enquêtés se révèle être en situation socio-économique très précaire et être souvent préoccupée par sa survie dans des conditions très difficiles. Ces dernières années, le Processus de Kimberley a pris l'initiative de concentrer sa réflexion et son action sur les questions environnementales. En 2012, la Déclaration de Washington, relative à l'intégration du développement de l'extraction artisanale et à petite échelle de diamants dans la mise en application du Processus de Kimberley, a souligné l'importance de prendre en considération les ramifications et conséquences environnementales de l'extraction minière artisanale. Dans cette optique, une enquête auprès des artisans mineurs en Côte d'Ivoire et une auto-évaluation de cette déclaration effectuée en 2014 en Côte d'Ivoire ont permis de comprendre que le cadre juridique, social, institutionnel et politique, constaté dans l'État Ivoirien, n'était pas toujours adapté au règlement des problèmes sociaux des artisans mineurs ni au règlement des questions environnementales soulevées par leurs activités minières. Ce travail de diagnostic de la déclaration devrait servir de modèle aux autres États de l'UFM. Les impacts des activités minières artisanales sur l'environnement existent donc mais il semble aussi que la remédiation des sites miniers artisanaux soit possible. En effet, le secteur de l'exploitation artisanale, à petite échelle de diamants a besoin de procédures de remédiation environnementale simples et de protocoles adaptés au niveau d'éducation des artisans mineurs et de leurs réalités financières. A ce sujet, la Sierra Leone a été un terrain privilégié d'expérimentation de la remédiation des sites miniers abandonnés à travers des projets gouvernementaux et des projets pilotes comme "Life after diamonds: Land Reclamation for Agriculture and Advocacy Pilot Initiative ". Ces projets ont contribué à protéger l'environnement et à améliorer les conditions socio-économiques des exploitants miniers. Cependant ces projets de remédiation quoique salutaires, ont eu aussi des limites qui méritent d'être prises en compte dans les futures initiatives des autres pays de l'UFM
Artisanal and small-scale diamond mining is practiced in all countries of the Mano River Union (Côte d'Ivoire, Guinea, Liberia and Sierra Leone) in a rudimentary and informal manner. However artisanal diamond mining is an important means of livelihood for most local communities in the Mano River Union. Based on our field research and surveys of miners, this type of mining has direct impacts on the forest ecosystem, soil and watercourses. In addition, the research shows that reducing the environmental impacts of artisanal and small scale diamond mining is not seen as a necessity or a major concern in the mining communities. There is often a lack of understanding and insufficient capacity to deal with environmental problems among artisanal miners, as revealed in our study of three mining sites in Côte d'Ivoire; Bobi, Toubabouko and Tortiya. Protected areas, which are of major ecological and socioeconomic importance for the populations of the Mano River Union countries, are unfortunately under pressure because of artisanal diamond mining. Especially since artisanal miners at the surveyed sites are often in precarious socio-economic situations more preoccupied by means of survival under very difficult working conditions. In recent years, the Kimberley Process has been focusing on environmental issues. In 2012, the Washington Declaration on Integrating Development of Artisanal and Small-Scale Diamond Mining in the implementation of the Kimberley Process highlighted the importance of considering the ramifications and environmental consequences of artisanal mining. To this end, a survey of artisanal miners in Côte d'Ivoire in 2014 made it clear that the legal, social, institutional and political framework of the Ivorian government, was neither adapted to the solution of the social problems of miners nor to the settlement of environmental problems caused by mining activities. This diagnosis should serve as a model for the other countries of the Mano River Union. The reclamation of artisanal mining sites is therefore possible in spite of the environmental impacts of artisanal mining. In fact there is a need for reclamation procedures and protocols adapted to the educational and financial realities of artisanal miners. In this regard, Sierra Leone has been a model in reclamation of abandoned mining sites through pilot projects such as "Land after Diamonds: Land Reclamation for Agriculture and Advocacy Pilot Initiative". These projects have helped to protect the environment and improve the socio-economic conditions of artisanal miners. However, these reclamation projects, although salutary, also have limitations which deserve to be taken into account in future initiatives of the other countries of the Mano River Union

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Hansen, John Olaf. "Wetting of the diamond surface." Thesis, 2015. http://hdl.handle.net/10539/16720.

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Guest, Alan Rex. "A study of mining induced fracturing in a diamond mine." Thesis, 2014. http://hdl.handle.net/10210/11486.

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Naidoo-Vermaak, Melanie. "The impacts of small scale artisanal diamond mining on the environment." Thesis, 2009. http://hdl.handle.net/10210/2391.

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M.A.
This mini-dissertation establishes the extent to which small scale artisanal diamond mining impacts on the environment. There has, in the past, been research undertaken specifically on the water related impacts of small scale artisanal diamond mining. This study however, looks at the environment holistically, and gauges the total degradation to the receiving environment. Small scale artisanal diamond mining is considered to be a major contributor to the local economy and improved quality of life for the communities participating in this mining and is being actively supported through the National minerals and mining policies. It is for this reason that it was deemed imperative to understand the nature of the mining and the associated environmental impacts so that the outcome of this report could be used to inform decision makers when considering the licencing and management of artisanal diamond mining operations. In order to achieve the aim of the study, a literature review needed to be conducted focusing on the nature of small scale diamond mining operations, its influence on the social and economic spheres and the known environmental damage induced by such mining activities. However, in order to internalize the impacts, the literature review also drew a comparison with large scale artisanal diamond mining. The problems identified at the four sample sites were evaluated through the OWL Risk Assessment method to gauge the high risks and major impacts. This study showed that water pollution, biodiversity depletion and waste generation were some of the main problems traversing all four sites. In all cases assessed, artisanal diamond mining impacts on the water regime as mining takes place within the riverine environment. This study also underscored the fact that there is very little, if any rehabilitation, of disturbed areas and this impacts upon fitness for use of the receiving environment in the long term. An urgent need exists for monitoring and regulating artisanal diamond mining so as to reduce the impacts to the receiving environment. More enforced regulation will also ensure that the mining operations practice responsibly with due care for the environment coupled to a legal undertaking for rehabilitation of the mining area.

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Eagleton, Stephen. "The importance of integrated sustainability reporting to the mining industry in Namibia." 2013. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001114.

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M.Tech. Internal Auditing
Mining can have a positive impact on Namibia by contributing towards economic growth and infrastructure development, by creating jobs, and by increasing foreign currency earnings; but on the other hand, the exploration of natural resources often runs in parallel with corruption, exploitation, environmental devastation, and population displacement through migrant labour. It is therefore imperative for mines to be sustainable in their operations: in other words, mines must protect and enhance the economic, social and environmental milieus of Namibia. The main objective of a mining company is profit maximisation through exploitation of natural resources, and the company can therefore be defensive, even antagonistic, towards sustainable operations and sustainability reporting. The pressure from mining companies' stakeholders for them to be transparent in their operations, and to report on all sustainability-related issues is increasing, and research has indicated that mining companies are, in the majority, supportive of the initiative, and realise the advantages of pursuing sustainable operations. Research results from the study indicated that between the different types of companies, and between countries, there is a significant variation in the sustainability reporting performance, both delivered and required. Improvement opportunities were identified in a number of areas with regards to the quality, consistency and extent of sustainability reporting. The rationale and the motivation for this study was therefore to determine the standard of integrated sustainability reporting being achieved by mining companies in Namibia, in order to determine the needs and shortcomings in the sustainability reporting arena. The final deliverable of this study was to develop a reporting framework which could enable enhanced integrated sustainability reporting by providing the mining industry in Namibia with a structured framework that conforms to world class standards.

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Shaduka, Ignatius Shikondjeleni. "Investigation of the groundwater evolution, interaction and potential radionuclide pollution from the unlined uranium tailings at Langerheinrich mine, Namibia." Thesis, 2016. http://hdl.handle.net/10539/21008.

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Groundwater is a very scarce and sensitive resource in many parts of the World especially in Africa and in arid areas such as Western Namibia. The Western Namibia hosts the Erongo region which named the Uranium Province world class deposits of uranium and high exploration and mining in the area. The majority of the Erongo region in Namibia depends on groundwater from the Swakop River compartment, hence, is important to understand the mining effects to this precious resource. The safe guarding of groundwater pollution from various sources including mining is vital. The extensive exploration and mining activities in the area raised environmental concerns especially threat to the huge ground water resources and the Aquatic systems in the proximity and hydraulically connected to the Swakopmund and Khan catchments. The study looked the impact of uranium mining in the area specifically focusing on the impact of the unlined uranium tailing dams at Langerheinrich uranium mine on the Gawib River a tributary of the Swakop River. The study reviewed the previous work on the Langerheinrich Uranium Mine that is related to groundwater pollution including the Environmental Impact Assessments carried out by the consultants for the mine. Ten water samples were obtained for the purpose of this study, the samples consists of the groundwater samples, recycled water and the fresh water supply to the mine. The hydrochemistry, stable isotopes and tritium results show that there is contamination from the unlined uranium tailings into the Gawib shallow aquifer system. This could spread to deeper aquifer systems mainly through major structures such as fractures and faults in the area. The contamination plume will also spread downstream to the Gawib River towards the Swakop River unless serious mitigation measures are put in place. There is also a very high risk of the plume to reach the Atlantic Ocean by seasonal flash floods that occurs in the area approximately every after few years. Keywords: Uranium Province, Langerheinrich uranium mine, Groundwater, Pollution, unlined tailings and Gawib River

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Axsel, Kenneth. "Government intervention and the resultant sector performance South Africa's diamond industry." Thesis, 2016. http://hdl.handle.net/10539/21328.

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A dissertation submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering. Johannesburg, 1993.
Since the discovery of diamonds in South Africa, Government has played an active role in the establishment of a local processing industry, aimed at the adding of value to locally mined rough diamonds. This study evaluates the influence of Government support and regulation in the performance of South Africa's diamond industry. Statistics were supplied mainly by the South African Diamond Board, the Minerals Bureau and the departments of Finance, and Trade and Industry. Discussions with prominent diamantaires were also undertaken to contrast statutory reporting with informally sourced facis. South Africa's diamond industry undetperforms, particularly the processing industry which benefits from State support at the expense of the other diamond sectors. Government's indirect support of the processing sector cannot be justified in view of its dismal performance. The entire diamond industry should be deregulaled, and State involvement in the processing sector (with special emphasis on the taxation structure) re-evaluated.
GR 2016

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Ngcobo, Sakhile Glen. "Corporate reputation in the South African diamond industry : a multi-stakeholder perspective." Thesis, 2016. http://hdl.handle.net/10539/23719.

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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

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Rukambe, Edlag Nyandee Uziruapi. "An assessment of the performance of health and safety strategies for managing lead waste : the case of Exxaro, Namibia." 2012. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000248.

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M.Tech. Business Administration. Business School.
This study investigates the extent to which levels of awareness of lead poisoning among mine workers at the Exxaro lead and zinc mine in Namibia correlate to their levels of compliance. Specifically, the study investigates the extent to which mine workers are aware of lead poisoning and whether this knowledge influences their attitudes towards compliance to regulations on handling hazardous materials.

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Chimeri, Munyaradzi Leo. "Worker's perception regarding the introduction of technology at Chiadzwa diamonds mines in Zimbabwe." Diss., 2016. http://hdl.handle.net/123456789/422.

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Taruvinga, Gwinyai Regis. "The governance of natural resources in Zimbabwe: the case study of the Marange diamonds." Thesis, 2016. http://hdl.handle.net/10539/21867.

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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

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Clynick, Timothy Paul. "Political consciousness and mobilisation amongst Afrikaner diggers on the Lichtenburg Diamond Fields, 1926-1929." Thesis, 2015. http://hdl.handle.net/10539/16516.

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Zvinowanda, Grace. "Characterisation and bioremediation of hydrocarbon contaminated soils: a case of Murowa Diamonds mine." Diss., 2016. http://hdl.handle.net/10500/22641.

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Microbial biodegradation methods of hydrocarbon contaminated soils that can occur through biodegradation, bio augmentation, bio stimulation, and phytoremediation, have gained significant interest in recent years when compared to the conventional methods. The study was designed to explore the influence of petroleum hydrocarbon contamination on physicochemical and microbial characteristics of soils as well as determining the possibility of hydrocarbon biodegradation using biostimulation. The process involved soil characterisation and modification of nitrogen and phosphorus content to stimulate naturally adapting microorganisms. Characterisation process determined that hydrocarbon contamination of Murowa soils introduced hydrophobicity to the naturally wettable sandy loam soils. Naturally adapting microbial species capable of degrading hydrocarbons identified using Direct microscopy, Gram and Melzer’s iodine staining included Pseudomonas, Bacillus, Serratia marcescens, Flavobacterium, Micrococcus, Streptomyces Staphylococcus, Penicillium and yeasts. The N: P nutrient ratio and moisture levels were identified as potential limiting factors and hence experiments focused on manipulation of N: P nutrients to stimulate the identified hydrocarbon degrading organisms (bio stimulation). Hydrocarbons were identified by solvent extraction using hexane and gas chromatography. These included decane, undecane, hexadecanal, 2-ethylcridine, octadecane and 1-iodo. Soils weighing 10kgs with hydrocarbons levels of about 265mg/kg were subjected to eight (8) treatments with seven (7) different combinations of N (6000-12000mgN): P (600- 3000mgP) concentration ranges including the control. Nitrogen The moisture was adjusted and tilling for aeration was done on a weekly basis. Changes in Total Petroleum Hydrocarbon (TPH), C: N: P ratio, microbial mass and pH were evaluated over 111 consecutive days. The optimum N:P ratio was the determined to 2:1 molar ratio in form of 6000mgN:3000mgP. TPH concentration was reduced by 73% from the initial concentration within the first 74 days. Beyond 74 days there were no significant changes in the TPH concentration and this was attributed to the presence of more complex insoluble hydrocarbons which needed more time and an additional bio surfactant to complete mineralization. The conclusion was that a combination of natural attenuation and biostimulation methods can be used to bioremediate Murowa hydrocarbon contaminated soils using the 2:1 molar ratio of what
College of Agriculture and Environmental Sciences
M. Sc. (Environmental Science)

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Dissertations / Theses on the topic 'Diamond mines and mining – Namibia'

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