A geological, petrological and mineralogical study of the UG3 chromitite seam at Modikwa Platinum Mine : significance to exploration and PGE resources
- Authors: Machumele, Nkateko Jones
- Date: 2014
- Subjects: Modikwa Platinum Mine (South Africa) , Chromite -- South Africa -- Limpopo , Geology -- South Africa -- Limpopo , Petrology -- South Africa -- Limpopo , Mineralogy -- South Africa -- Limpopo , Platinum mines and mining -- South Africa -- Limpopo
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5074 , http://hdl.handle.net/10962/d1013553
- Description: The UG3 at Modikwa Platinum Mine occurs as a platiniferous, planar chromitite seam. It is stratigraphically located in the Upper Critical Zone of the Eastern Bushveld Complex. Field work study comprise of underground mapping, sampling, surface mapping, borehole core logging, microprobing and microscopic investigations carried out at the Rhodes University. The UG3 at the Modikwa Platinum Mine is about 22cm thick chromitite seam underlain by a white fine grained anorthosite and overlain by a brown medium grained feldspathic pyroxenite. It is an incomplete cyclic unit consisting of chromite and feldspathic pyroxenite. The UG3 reef at the Modikwa Platinum Mine lease area represents a Platinum Group Metal resource of 300 million tons of ore at an in situ grade of 2.5g/t. Under the current market conditions the UG3 reef remains unprofitable to mine in an underground operation due to the operational cost involved. However, it has been illustrated that the UG3 chromitite seam can increase profit margins in an open pit operation provided it is mined together with the economic UG2 chromitite seam. The extraction of the UG3 as ore in the four Modikwa UG2 open pits would result in a combined operating cash profit of R330 million. The UG3 chromitite seam is platiniferous. The platinum-group minerals (PGM) range in size from less than 10μm to about 70μm. The PGMs are associated with sulphides and are both located in the interstitial silicates and are concentrated in the chromitite seam. The PGMs show a strong preference to contact boundaries of the silicate grains, the chromite grains and the sulphide phases. In some instances, they are enclosed within the chromite grains in association with sulphides. The general sulphide assemblage comprises pentlandite and chalcopyrite whereas, the PGMs assemblage comprises cooperite, ferroplatinum, laurite, FeRhS and PtRhS.
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- Date Issued: 2014
Imagine/nation : mediating 'xenophobia' through visual and performance art
- Authors: Machona, Gerald Ralph Tawanda
- Date: 2014
- Subjects: Xenophobia -- South Africa , Xenophobia in mass media , Performance art , Immigrants in art , Violence in art , Race in art
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:2480 , http://hdl.handle.net/10962/d1011106 , Xenophobia -- South Africa , Xenophobia in mass media , Performance art , Immigrants in art , Violence in art , Race in art
- Description: This half-thesis has developed as a supporting document to an exhibition titled Vabvakure, people from far away, which responds to the growing trends of violence perpetrated against African foreign nationals living in South Africa. This violence which has generally been termed as 'xenophobia' has been framed within this discourse as 'afrophobia', as it is fraught with complexities of race, ethnicity and class. Evidently, not all foreign nationals are at risk but selective targeting of working class black African foreign nationals seems to be the modus operandi. Fanning these flames of prejudice are stereotypes and negative perceptions of Africa and African immigrants that have permeated into the national consciousness of South Africa, which the mainstream media has been complicit in cultivating. My practice is concerned with challenging this politic of representation in relation to the image of the African foreign national within South African society, who have been presented negatively and labelled as the 'Makwerekwere', the 'bogeymen' that have been blamed for the country’s current woes. In response to this, my research adopts the premise that forms of cultural mediation such as visual and performance art can offer further insights and possibly yield solutions that can be used to address these sentiments. As globalisation and neoliberal ideologies reshape the world, there is a growing need in the post-colonial state to revisit and re-construct notions of individual and collective identity, especially that of the nation. Nations, nationalisms and citizenry can no longer be defined solely through indigeneity, for as a result of radical shifts in the flow of migration and immigration policies that allow for naturalisation of aliens and foreign nationals, we are now faced with burgeoning levels of social diversity to the extent that constructions of nationhood that are based on the concept of autochthony have resulted in the persecution of the ‘other’.
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- Date Issued: 2014