Mine Premier

Bultfontein, De Beers and Premier mines, Kaapvaal (Lawless et al., 1979). Malaita... 

Without the high regard, that gem diamonds enjoy in our society, the extraction of natural diamonds would be completely uneconomic. Even in the rich Kimberley seams in South Africa, only 2.5 carats (0.5 g) of diamonds are obtained per t of processed rock, only 0.4 carats of diamond being obtained in 1985 in the Premier Mine (also in South Africa). 

Danchin, R. V. 1979. Mineral and bulk chemistry of garnet Iherzolite and garnet harzburgite xenoliths from the Premier Mine, South Africa. In Boyd, F. R. Meyer, H. O. A. (eds) The Mantle Sample Inclusions in Kimberlites and Other Volcanics, Proceedings of the Second International Kimberlite Conference. American Geophysical Union, Washington, DC, 104-126. 

Of the on-craton peridotites studied so far, the suite from the Premier mine, in the centre of the Kaapvaal Craton, is the only one to have an average Trd age that is not Archaean (Table 2). 

The Cullinan Diamond is a famous stone. In 1897 Thomas Cullinan purchased a faxm near Pretoria in the Transvaal, which was believed to contain diamonds and so it proved in a few years the land was valued at 20 million. In 1903 a diamond mine was discovered there which came to be known as the Premier Mine, and in January 1905 a diamond was unearthed, the largest gem... 

Kimberliteisthe principal diamond bearing ore. In atypical mine such as the Premier Mine near Pretoria, South Africa, one hundred tons of kimberlite produce an average of thirty-two carats of diamond (6.4 g). Dieimonds are sorted from the mineral by an x-ray beam the diamond luminesces with the x-ray and the luminescence activates an air Jet which propels the diamond into a separate bin (Fig. 12.1).i ] Gemstones (a very small percentage) are then separated from the industrial-quality material. 

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