By 1930 over 11 million carats of diamonds had been recovered in an area south of Luderitz. Further discoveries were made along the southern coast onshore areas heading south towards Cape Town.

Few people had ventured into the sea itself to continue the search for diamond deposits and it wasn’t until the arrival of Sam Collins in the early 1960’s that exploration of the seafloor revealed that diamond deposits did in fact extend into the sea along submerged ancient beach terraces.

Some 1.5 million carats were extracted from the sea between 1961 and 1970. Collins alone recovered 380,000 carats in a 15 month period in 1969/70.

The marine diamond production from the coastal waters of Namibia, where most of the marine mining activity takes place at the moment, reached 600 000 carats during 1995. (1994 = 550 000 carats; 1993 = 376 400 carats). This production equates to a value of some US$170 million. Compared with the 1995 production of some 750 000 carats from the mines on land in Namibia, a major shift towards marine diamond production is evident in that country.

at Alexander Bay and Oranjemund. These spectacular deposits on land lured people towards the adjacent sea areas, and the first diamond recoveries from the sea date as far back as 1957. However, it was only with the arrival of the Texan entrepreneur, Sam Collins, in the 1960's that marine diamond mining gained momentum. As the exploration of the seafloor developed, it became clear that diamond deposits similar to those exposed along the present day coast line occurred along submerged ancient beach zones.

Collins founded Marine Diamond Corp. and mobilized a series of barges equipped with centrifugal and airlift pumping systems recovering diamonds in the shallow waters by De Beers’ huge Orange River mouth enterprise. The barges housed processing plants and basic accommodation for the operating crews. The barges were moored with multi point anchoring but struggled with the large South Atlantic swells. More than one barge ended up on desolate beach areas.

The richness of these marine deposits is perhaps best illustrated by the recovery of 300 000 carats (worth some US$36 million at today's prices) between June 1969 and September 1970 from a small area in Hottentot Bay, north of Luderitz by Tidal Diamonds Company.

Although some 1,5 million carats of diamonds were produced from the sea off the Namibian coast between 1961 and 1970, these early attempts to mine diamonds off the west coasts of South Africa and Namibia nevertheless failed for a variety of reasons. Some of these problems included the low diamond prices at the time, the lack of suitable technology and the lack of understanding of geological controls of diamond deposits on the sea floor.

The De Beers Group, who later took over the operations of Sam Collins, curtailed mining operations in 1970 and commenced with an extensive 15 year exploration programme. When De Beers started their next phase - the commissioning of mining vessels for offshore diamond mining in the late 1980's - the interest of investors and other mining groups was stirred again. Today, with vastly improved and developing technology, marine diamond mining has become a highly sophisticated industry.

The De Beers Group is the most advanced in the industry and controls the major portion of the concession areas in the sea, along both the South African and Namibian coasts. They currently operate four mining vessels and reported production of more than 450 000 carats during 1995.