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Gk 12 Mr Hoch Mining in South Africa Krugerrand South Africa has a great number of minerals, the two most prominent among others are gold and diamonds. Since 1886 South Africa has been the Gold Producing Mecca of the world. From that year forward the southern-tip African country has literally dominated the global gold scene. At its peak production in 1970 South Africa contributed 79% of the world's annual supply of the noble yellow. Its dominant position has waned in the last 30 years although it is still Numero Uno in total gold production, followed by the North-America and a distant third Australia. Today, South African gold mines supply about 25% of the world's yearly production …(full article here). The development of the South African diamond industry is inseparably linked to the rise of the De Beers empire... (full article here) The diamond resources in the Kimberley region are considered primary, because this is where they formed millions of years ago. Diamonds are nothing but carbon compounds, which crystallised long ago under extreme pressure and high temperatures in deeper layers of the earth crust. Volcanic activities set them free. The pressure of the earth's magma caused the formation of pipes in the earth crust, through which the magma erupted as a volcano. The diamonds are enclosed in these pipes, which consist of volcanic stone, the so-called Kimberlite. By drilling into the pipes from the side, miners excavate the diamond-containing stone. Ten tons of stone usually contain one or two carats of raw diamonds, one carat equalling about 0.2 grams. The "Big Hole" of Kimberley, itself is an astonishing sight. Mined to a depth of 215 metres, and with a surface area of about 17 hectares and a perimeter of about 1,6 km, it is the largest hand-dug excavation in the world. On 14 August 1914 work on the mine was suspended. By that time 22,5 million tons of earth had been excavated, yielding 2 722 kilograms of diamonds.