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.

Diamonds of South Africa

The development of the South African diamond industry is inseparably linked to the rise of the De Beers empire. It was the young Cecil Rhodes who founded the De Beers mining company in Kimberley in 1888. He named it after the original owners of the Zandfontein farm. Rhodes was fought intensely against competing owners of other mines, and by the end of 1889 he had the South African diamond industry under his control.

At that time the quantity of diamonds produced could be manipulated and the price kept to a profitable level. But with the discovery of new resources near Pretoria and in South-West Africa (Namibia) the predominance of De Beers was broken. Ernest Oppenheimer, an immigrant from Germany, with his Consolidated Diamond Mines (CDM), founded in 1919, became the leader in the field. In 1929, Oppenheimer also became president of the De Beers group and eventually united both companies in a cartel.



Top: Uncut raw diamonds. Centre: Diamond cutter at work. Left: Ernest Oppenheimer. Bottom right: The historical building of De Beers Mining Company.