JOHANNESBURG--February 19, 2013--Written by Richard Finlayson, Senior International Editor for Industrial Info Resources (Sugar Land, Texas)--The De Beers Group (Luxembourg) plans to build a new underground mine below the current Venetia open pit diamond mine in Limpopo province, in northern South Africa. Venetia is the biggest diamond mine in the country. The company, which is controlled by Anglo American (LSE: AAL.L) (London, England), announced last week that it would invest $2 billion in the expansion project, which would extend Venetia's operational life through 2042.