Diamonds were formed more than 3billion years ago under extreme heat and pressure below the earth's surface.
The earliest diamonds found here were Alluvial diamonds, meaning these diamonds moved from their original position by erosion over millions of years. Hence why deposits are found in river beds, the ocean floor and along some shorelines.
Kimberley was known as the diamond capital of the world. Between 1871 & 1914 over 50,000 miners dug the Kimberley hole with picks and shovels. About 2,720kg of diamonds was excavated here.
The Big Hole is 463m wide and 240m deep. Today, only 175m is visible, as rubble and 40m deep water now partly fills the hole.
Diamonds were later found in Cullinan, in 1902, and in Venetia. The Finch mine opened in 1967. Alluvial diamonds are worked along the southern banks of the Orange River and along the west coast.
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