Marine Mining of Diamonds Off the West Coast of Southern Africa

Abstract

A vast resource of gem-qnality diamonds exists off the west coast of southern Africa. Over the course of millions of years, many diamond-bearing kimberlite pipes in the Orange River drainage basin have been extensively eroded and the released diamonds transported to the west coast. Raised marine deposits now on land have yielded almost 100 million carats of predominantly gem diamonds; similar marine deposits and feeder channels are now known to exist offshore. Techniques for exploiting the offshore resources have been proved on a small scale in shallow (