The dissertation reviews the present knowledge regarding diamonds, from its formation in the lithospheric upper mantle at depths between 150 and 300 km, to its final valuation in terms of US$/carat by diamantaires in London, Antwerp, Tel Aviv and New York. The dissertation is divided into two complimentary sections. Section one focuses on the formation, emplacement, occurrence and characteristics of kimberlites and, when present, their associated trace amounts of diamonds. The section follows a logical sequence from the regional tectonic-, local structrual- and geodynamic controls on kimberlite formation and emplacement to the characteristics of individual kimberlite morphology, mineralogy, petrography and geochemistry. Finally, the environment or diamond formation, resorption and the characteristics that have led to the marketability of diamonds are discussed. Section two reviews the current exploration techniques used in locating diamondiferous kimberliies and the subsequent economic evaluation of these kimberlites. A brief history of known Southern African kimberlite occurrences, grades, tonnages, tectonic settings, ages and regional structural controls is given. The prospective countries mentioned are Angola, Botswana, Lesotho, South Africa, Swaziland, Tanzania and Zimbabwe. Exploration techniques considered are ; the application of a landscape analysis and investigation of the surface processes active in a given area, indicator mineral sampling (with reference to their mineralogy and exploration significance), remote sensing techniques (subdivided into satellite imagery and aerial photography), geophysical techniques (including the magnetic-, gravity-, electrical-, radiometric- and seismic methods as well as heat flow models), geochemical techniques, petrographic- and electron beam techniques as well as geobotanical- and geobiological techniques. Finally, a brief summary of current evaluation techniques employed on diamondiferous kimberlite deposits is presented. The review covers kimberlite sampling methods, sample processing, diamond grade distributions (with reference to the experimental variogram model, statistical methods used in grade distribution calculations as well as block definition and local grade estimation). Stone size distributions, including microdiamond counts and value estimation, are also discussed. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in

The South African wine market is undergoing changes at both the producer and retail levels, such as the influx of the new brands and new consumer demands with respect to health, biodiversity concerns and ethical issues. Although South Africa has no dominant wine culture and South Africans are predominantly beer and brandy drinkers, the industry has to develop the local market, especially the black consumer market. The most powerful marketing trend in the South African economy in the last 10 years has been the emergence and growth of the black middle class, increasingly referred to as Black Diamonds, which have emerged as the strongest buying influence in the economy. This has seen the propagation of a westernized culture in local communities. There is an overwhelming desire among the latter group to have access to a lifestyle they believe is their right. Making inroads in understanding this market presents a good opportunity since this is an important economic group. Black wine drinkers have to overcome individual families' attitudes to wine drinking. It is high on the industry’s agenda to swing the emerging black middle class market from high-end whiskies, cognac and beer, to wine while at the same time promoting the wine culture because this market is still hugely untapped. They also seek to vanquish the illusion of wines as a drink for white people by focusing on young upcoming black professionals as a target market. The data in this study was collected from an integration of a consumer behaviour survey (through a choice based conjoint analysis undertaken at the Soweto wine festival in Johannesburg); as well as personal interviews with industry stakeholders and reference group discussions. The study found that although there is limited consumer knowledge about wines and low levels of brand awareness, black consumers are willing and yearning to learn more about wines as they view them as an aspirational lifestyle beverage. The study also asserts that women are significantly more adventurous than their male counterparts in terms of experimenting with wines although the latter exhibit a higher willingness to pay for what they consider to be premium wine brands. Black consumers are still unsure about what wine attributes are important in choosing a wine. The industry needs to increase its efforts in educating and understanding this diverse market as the cultural attitudes towards wine are indeed changing. The study identified four wine consumer market segments among the Black Diamonds. The industry’s target market should be focused on women and the “Start me up” age group as they show the highest willingness to learn about wines and pay for brands that they consider to be premium brands as has been the case in all new wine markets. While still focusing on the 4 P’s of marketing, various new brand communication platforms can be explored to reach this market. These include co-opetition, extended service offerings, wine tourism and e-marketing. The success of the domestic market will be determined by new innovative insights into this market and complimentary market strategies. / Dissertation (MSc(Agric))--University of Pretoria, 2009. / Agricultural Economics, Extension and Rural Development / unrestricted

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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.