Gemstones Tools


Brown diamond oval cut

Diamonds were first discovered in India, probably around 800 B.C.
Until 1725, India’s market city of the diamond trade, Golconda, was fabled to be the source of these gems. In fact, these diamonds were mined in the surroundings of this city. Smaller quantities also came from Kalimantan (Borneo).

The primary volcanic source of these gems was never discovered during the almost 2500 years in which the Indian sub-continent was the only producer of diamonds. These alluvial deposits were rich enough to supply the world until the eighteenth century.

Before the Portuguese discovery of a direct sea route to India, diamonds reached Venice by two Mediterranean routes: a southern route by way of Aden, Ethiopia and Egypt; and a northern route, through Arabia, Persia, Armenia and Turkey.

A diamond-cutter’s guild was established in Antwerp., helping this city flourish as a diamond center with vast supply of rough arriving from Lisbon as well as from Venice, and later from London, as the English fortified their interest in India in the late 1600’s. Only one exception: after the attacks on Antwerp in 1585 by the Spanish army, many diamond cutters moved to Amsterdam.
Diamond craftsmen, many of them Jews fleeing religious persecution in Spain, Portugal, Germany and Poland, were attracted by the liberal policies of the Netherlands. But a change in fiscal policies in the Low Countries caused diamond cutters and traders to move back to Antwerp..
Today, this city handles more than 80% of the world’s rough diamonds, as well as half of its polished diamonds, continuing thus a tradition of over 500 years of cutting and trading.

Diamonds rough and cut As the Indian production started to wane, diamonds were discovered in 1725 in Brazil. These deposits were able to maintain a steady supply of small stones after 1730.
Large quantities of significant size stones appeared on the market only with the exploitation of the South African diamond fields from 1866 onwards. The discovery of these deposits also led to the first sudden increase in supply. This increase coincided with the new wealth generated by the Industrial Revolution and the corresponding rise in the demand for luxury goods by a broader range of consumers.

South Africa's alluvial diamond deposits were discovered near the Orange River.
Further exploration in the Kimberley region revealed for the first time volcanic formations called "pipes" filled with an unknown type of rock that contained diamonds. This rock, a variety of peridotite, was named "Kimberlite" after the region of its first discovery, was recognized as the diamond’s source. Only Western Australian diamonds have a different source, which is a closely related rock type, lamproite.

The discoveries in South Africa led to a rush of prospectors staking out numerous claims. Mining by hazardous open-pit operations prevented rational exploitation of the diamond fields. In 1889, Cecil Rhodes and Barney Barnato bought out these claims and merged their interests in De Beers Consolidated Mines, Ltd. in South Africa, establishing a monopoly on the diamond trade that remains today.

In 1992, a whole new field of diamantiferous kimberlite pipes was discovered in the Northern Transvaal, and in 1993 production has moved to a peak of 5 millions carats, scheduled to be maintained for the next 20 years.Nevertheless, on the world market the South African diamond output is today rivaled by exploitation of the major deposits that were found in Australia, today the world’s main producer with an output average of over 25 millions carats annually, approximately 25 % of annual world production.

Worldwide famous, the Australian Argyle mine was able to produce 42 millions carats in 1994. Other pipes in the same region are under evaluation. The Argyle mine is also famous for the high percentage of yellow and brown material, known also under the name of “Champagne” and “Cognac,” and the constant recovery of a small amount of pink to red stones.

This pink to red material is sold as cut stones in private auctions, or “tenders”. Viewings are held annually in New York, Sydney, Hong Kong, Tokyo, London and Geneva, where polished pink diamonds with an average weight of about one carat, typically achieve prices in the 100 000 USD per carat. To put the rarity of these diamonds into perspective, about one carat in one million produced in this mine is suitable for sale at these auctions.

Yellow diamond oval cut Since 1829, diamond production has also begun in Russia with the discovery of alluvial diamond deposits in the Northern part of the Ural Mountains. But it was not until 1954 that abundant kimberlite pipes were discovered in the permafrost of Yakutia, Siberia. Yakutia adopted in 1992 a new Constitution, and was renamed the Republic of Sakha. This Republic is today another leader in diamond mining: it produces 99% of Russian diamonds, accounting to 20% of the world diamond mining.

The Russian diamond mining and processing industry, at the initiative of the government, is developed without foreign participation.
Its main deposits are situated in the Western part of Sakha (990 thousand square km), where 18 kimberlite fields were found. Uduchnaya, Mir, Aikhal, Internacionalnaya, Jubileinaya diamond pipes, are well known around the world, earning to this vast region in the Sakha Republic the name of “the diamond province”.

South Africa is not the only producer in its continent. Many alluvial deposits or kimberlite pipes have been found in other countries, especially Namibia, Angola, Botswana, the Democratic Republic of Congo (formerly Zaire), Tanzania, Ghana, Sierra Leone, Liberia, Gabon, Cameron, the Central African Republic and Zimbabwe.
Botswana with its Orapa mine, produce yearly and average amount of 5 Millions carats, while the Kalahari Desert Jwaneng mine produces 6 millions carats per year.
Democratic Republic of Congo (formerly Zaire) with its production of mainly low grade and industrial quality is the second biggest world diamond producer after Australia.
Angola, another important diamond producer, exports up to 2 millions carats of good quality annually, but its uncertain political situation has hindered organized mining and prospecting. With the recent peace underway, there is no doubt that Angola will be a big player in the international diamond market.
Ghana has always produced more diamonds than the other West African countries but for the most part these stones are much smaller. Their value per carat varied from 10 to 20 USD compared 250 to 300 USD for stones from Sierra Leone where large and exceptional quality diamonds are produced since 1935.
Liberia, a small size producer from the end of the 90’s represents a special case. Many of the diamonds exported from this country until mid 2002 are the so-called “blood diamonds” or “conflict diamonds”. This appellation means sold by rebels and governments to fund their war campaigns, principally in Sierra Leone. To a broader extend, these names were also applied to diamonds from Angola and the Democratic Republic of Congo.

The international community, concerned about the increasing negative impact on the consumer, took measures, signed in Interlaken, Switzerland, by more than 50 nations involved in the diamond trade to stop this diamonds for weapons trade.
The resulting agreement, known as the Kimberley Process, started since January 1, 2003. It proposes an independent certification expert system for tracking rough diamonds origin.
But recent peace treaty between belligerents in Angola and the withdrawal of foreign armies in Democratic Republic of Congo will hopefully put an end to this trade.

Diamonds are also found in the United States in Arkansas, California, Colorado, and North Carolina.
In 1990, extensive diamond pipes were found in Canada's Northwest Territories. Today Western Canada is the site of the world's newest diamond rush.

Diamond cutting centers are found all over the world, most notably in Belgium, India, Israel, South Africa, Thailand, China and the USA.

in Antwerp

Some advices to buy a diamond in our Antwerp trading office...