Rough diamonds are currently mined in 25 countries and on every continent except Europe and Antarctica from openpit, underground and offshore sites, Creamer Media’s Research Channel Africa reports in its Diamonds research report.



Rough diamonds can be divided into two types – gem diamonds and industrial diamonds.



Gem diamonds are used in jewellery, and can vary in colour from pure blue-white through pale yellows and browns, to the rarest shades of pink and blue.



Industrial diamonds are either of an inferior quality to gem diamonds, or they have an undesirable colour. They find a place in industry, however, owing to the fact that diamonds are the hardest known natural substance.



Industrial diamonds can be used in cutting, grinding, polishing, wiremaking and drilling applica-tions, as well as in the building and construction of roads and in oil-well drilling.



The one limitation of diamonds in industrial applications is that they react negatively to iron at high temperatures, reverting to graphite, and thus causing high rates of wear. This makes diamonds uneconomic in some instances.



It is possible to manufacture synthetic diamonds for industrial use, which has resulted in a clash between synthetic and natural diamonds to achieve dominance in the market. However, owing to sheer weight of numbers, synthetic diamonds have won the battle, forcing natural diamond abrasives to find niche markets where particular properties, which are difficult to simulate in the synthetic product, are required.



Africa is the richest continent for diamond-mining, accounting for almost half of world production. The main African sources are in the south, with lower concentrations in the west and central parts of the continent.



Diamond-mining on the African continent



Botswana



Mining giant De Beers discovered several major kimberlite pipes in Botswana between 1967 and 1973.



The first, the Orapa pipe, is the second-largest economic kimberlite pipe in the world, and produced 14,9-million carats in 2005. The Jwaneng pipe, discovered in 1973, is the most valuable diamond mine in the world and produced a record of 15,6-million carats in 2005. Two smaller pipes, Letlahkane 1 and 2, were discovered in 1968.



Botswana reaffirmed its position as the world’s largest diamond producer by value, and the world’s second-largest producer by volume, an increase of 2% over 2004, according to the Directorate: Mineral Economics 2005.



South Africa



With the exception of KwaZulu-Natal, diamonds have been discovered in all the provinces of South Africa.



Limpopo province is the biggest producer, followed by the Northern Cape, Gauteng, Free State and North West province.



The Western Cape is a minor producer, with the West Coast alluvial and marine deposits extending into the north-western corner of the province.



A few small kimberlites are found in Mpumalanga and some alluvial occurrences have been reported on the south bank of the Orange river in the Eastern Cape.



In South Africa, De Beers Consolidated Mines (DBCM) produces some 95% of the nation’s diamond output.



Angola



Angola’s diamond production is mostly controlled by State-owned Empresa Nacional de Diamantes de Angola (Endiama). Endiama’s current capacity is about six-million carats a year, with plans to produce 12-million carats yearly.



The production increase is due to the start-up of the parastatal’s new exploration and production arm, Endiama – Prospec��o & Produ��o and expected new production from six diamond projects coming on line.



De Beers and Endiama have reached an overall agreement for the granting of mineral rights to a joint venture (JV) between the two companies for the exploration and evaluation of kimberlites in the Lunda Norte province of Angola.



This JV represents a historic milestone that supports the develop- ment of the Angolan diamond industry and contributes to the efforts of the government of Angola to rebuild the social and economic infrastructure of the country.



Democratic Republic of Congo (DRC)



The DRC was the world’s sixth-largest producer of diamonds in terms of value, and fourth in terms of volume, producing an estimated 27-million carats, in 2005.



Miba, which is also known as Soci�t� Mini�re D Bakwanga, is the DRC’s biggest diamond-mining company. It produces about 7,5-million carats a year, is 80% owned by the DRC government, and 20% owned by Belgian company Sibeka, of which De Beers has a 20% share. Miba has traditionally focused on nongem-quality diamonds, but is now looking at mining gem-quality stones.



Namibia



The largest diamond producer in Namibia is Namdeb, a JV between government and De Beers, which produced 1,8-million carats in 2005.



History was also made when Namdeb production from marine resources overtook land production for the first time. As a result, De Beers Marine Namibia became the biggest diamond-miner in Namibia, producing a total of 976 890 ct. However, this was an overall 5% decrease over 2004 owing to operational problems at land operations.



Diamond-mining globally



Russia



Almazy Rossii Sakha (Alrosa) is one of the world’s major rough- diamond producers and accounts for 100% of all rough-diamonds produced in Russia and about 20% of the global rough-diamond output.



Alrosa is the biggest diamond company participating in exploration, mining, manufacture and sales of diamonds in Russia.



Canada



The production and profitability of the Diavik and Ekati mines in the Northwest Territories, as well as possible new production areas in other parts of the country, have attracted much attention to the Canadian diamond-mining industry.



Ekati’s average production over its projected 20-year life is expected to peak at three-million to five-million carats a year. This equates to 4% of world production by volume.



During the projected 20-year life of Daivik, Canada’s second diamond mine, diamond production is expected to peak at six-million to eight-million carats a year, about 5% of the total global supply.



Australia



Most of Australia’s diamond production comes from the Argyle diamond mine located in the East Kimberley region of Western Australia.



In 2005, Argyle’s production was 30,5-million carats, about 20% of the world’s yearly production.



Production has been decreas- ing for years as the openpit is exhausted, while severe wet weather from cyclones also creates problems.



The owner of the mine, Rio Tinto, has decided to switch to underground mining when the openpit is exhausted in about 2008.



The vast majority of the diamonds produced at Argyle are of industrial quality, with only relatively small amounts of the famous Argyle pink and champagne-coloured stones.

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