Dignified understatement describes the cousins Oppenheimer.

In the land of their discovery over two thousand years ago, they were treasured by the Indians for their magical properties and used as protection from the forces of evil. In ancient Greece they were believed to be fragments of stardust and their unique resistance to both fire and steel saw them become a symbol of unconquerable strength which in turn gave them their name. They became an essential component of countless Crown Jewel collections and a favourite collectable of countless monarchs: by the end of the eighteenth century they had become the only choice for ladies in society. The nineteenth century saw them become the chosen status symbol of newly - moneyed industrialists. During Hollywood's Golden Years, F. Scott Fitzgerald celebrated them in literature, Marilyn Monroe celebrated them with Elizabeth Taylor. Today they are coveted by investors for their monetary value, by industry for their durability and by women the world over for their sublime beauty and evocations of romance and eternal love.

Diamonds have also been a magnet for a rare breed of entrepreneur. Possessed of a singular vision and passion, as rare and brilliant as the stones they so covet, these characters shine brightly the world over. In London, people such as Laurence Graff and the Moussaieffs, in Switzerland, Theodore Horovitz and Tabbah, in New York, Harry Winston and William Goldberg, Van Cleef & Arpels and Tiffany, Cartier and Boucheron in Paris, the list is elite and endless; all personalities as unique as the stones themselves but perhaps, the most unusual name is that of the Oppenheimers. In a world of exotic and eccentric personalities, Nicholas and Anthony Oppenheimer are remarkable by their very sobriety.

The cousins Oppenheimer, are arguably the most valuable gems in the collection given their shared position as Executive Directors of the world's premier diamond organisation, De Beers Consolidated Mines, with its related marketing instrumentality, the Central Selling Organisation (CSO). Despite the grandeur of their position and the product, they themselves present with a restraint and paradoxical understatement.

"We are really quite ordinary... It disappoints me as well, but it's true," insists Nicky, almost apologetically, in precise considered tones that evoke a diplomacy long past. "Most people think I'm the piano tuner because there are a lot of Oppenheimers who tune pianos," adds Anthony, with similar reserve.

Far from tuning pianos, the two men seem totally at ease with their present responsibilities in the most glamorous of industries. They are both practical yet far from diffident in their analysis of the business of diamonds.. "I don't think that you could find a more fascinating business than the diamond business," muses Nicky. "It has this wonderful combination of being... well, useless, and yet being wonderfully desirable as well: The most beautiful jewel you can own, it has a currency value and touches all these strings of romance. I like this business because I deal with all these marvellous personalities. You see, diamond designing requires confidence in your vision and bravery given the sums involved, and this, either produces or attracts 'characters'. If you are a characterless person, you won't be able to make the decisions necessary to be successful.

"The successes are entrepreneurial and they are people with a certain sensitivity. I like this business because we are dealing with very substantial sums of money. Last year for instance, the CSO sold $4 billion worth of diamonds. I like it because it is a rarefied atmosphere where a gentleman's agreement holds.

Dealing in any other business, you would be surrounded by your lawyers and accountants. This is a family-oriented business when you go to visit the dealers, you find yourself taking to their wives and children. It's very gratifying."

De Beers itself, although a major public company , is run with the many attributes of a family business, and both Nicky and Anthony's fathers in their eighties, remain on the board of directors and make a daily appearance at the London office. "I think that we would be a bit despondent if they didn't" confides Anthony. "I suppose that I am old-fashioned in the sense that I think the pendulum has swung too far the other way where people have become terribly impersonal and are only loyal to their salary. I feel it's terribly important to have a sense of loyalty and family orientation.

It is a philosophy which, combined with commitment to orderly marketing through the CSO, has seen De Beers grow over the last hundred years through three generations of Oppenheimers into the international corporation whose name is synonymous with diamonds. The story of De Beers is the story of both the South African nation and the modern diamond industry and in a suitably romantic fashion, began when a young farm boy wandering around the northern borders of Cape Colony in 1866 - South Africa then being little more than a collection of African states, republics and colonies - stumbled upon a lustrous stone in the fields. The gem found its way to London and the House of Garrards, Queen Victoria's personal jewellers, who confirmed its quality and young Erasmus Jacobs' stone became the beautiful 10.73 carat Eureka Diamond. The discovery of a second stone a couple of years later, silenced the sceptics and produced the impressive 47.75 carat Star of South Africa.

Prospectors arrived in their thousands to make their fortunes along the Vaal River but the glittering bounty was to be discovered a few kilometres away over a four acre stretch of land that in part contained the farm of one Johannes De Beer. When De Beer sold his property he was not to know that the four volcanic 'pipes' in the Kimberley region, some of which lay deep beneath the De Beer farm, were to produce two million carats of diamonds by 1880, the year the De Beers company was formed. One of the founders was none other than Cecil Rhodes, a dynamic visionary who not only unified the various mines under the banner of De Beers Consolidated Mines in 1886 but found time to become Prime Minister of the Cape and create the nation of Rhodesia, all the while maintaining his active involvement with De Beers. Even today, long after his influence is felt through the prestigious Rhodes Scholarships to the University of Oxford.

Rhodes' empire was not created without difficulties and the amalgamation of the mines was preceded by a take over battle that would shame many of the current crop of corporate raiders. Speculation forced the share value of the mines to 25 million whilst opposition shareholders frustrated takeover attempts for over a year. But as Spring blossomed over 1889, a now legendary cheque for UKP5,338,650 saw the Kimberley Mine join the De Beers consortium. It was now possible to pursue their plan of regulating the flow of diamonds entering the marketplace and ensuring price stability.

Unfortunately, for De Beers, new discoveries of diamond deposits undermined their work, in particular, the Premier Mine in Pretoria which in 1905 yielded an incredible 3,106 carat stone. Cut to a still magnificent 530 carats and named after the mines' founder, the Cullinan Diamond was added to Queen Victoria's collection. Lengthy negotiations resulted in Premier allowing De Beers to manage its production and prices through a combination of leading gem merchants known as the Diamond Syndicate.

"It was about the turn of the century that my grandfather became involved," explains Nicky. Ernest Oppenheimer was German by birth, had learnt the diamond business in London, consolidating his skills in South Africa, and had amassed a considerable fortune in gold early this century, forming the Anglo-American Corporation with the aid of American and British bankers. Though Nicky modestly fails to mention how his grandfather was knighted for his efforts against the Germans in World War I, he does explain how he benefitted from the fortunes of war. "During the War, he owned concessions in the mines and when their full potential was realised he made a handsome profit which gave him the foothold he needed to gain an interest in De Beers."

By this time, the four founders and 'Life Governors' of De Beers, including Rhodes, had all died and Ernest Oppenheimer, through his Ango-American Corporation, had added to his South African mines, with acquisitions in the Congo and Angola, West Africa and British Guinea. In what seemed an effortless rise, he firstly took control of the Diamond Syndicate business in 1925. A year later he gained a formal place on the board of De Beers and in 1929, Ango American launched a successful takeover of De Beers. Thus Sir Ernest Oppenheimer realised a life long ambition in becoming Chairman of the Board, a position which enabled him to begin the transformation of De Beers into an international organisation without peer.

The eve of the Great Depression saw Oppenheimer place all his diamonds assets under the De Beers aegis and create a new marketing body, the Diamond Corporation. As the world economy began to stabilise, this was restructured into the Diamond Trading Company which, in time, was to become the existing Central Selling Organisation. In addition, a Diamond producers Association was established to set quotas on production.

"De Beers and the CSO have a very complex infrastructure," explains the Marketing Director, Richard Dickson. In an industry that the markets its wares in 28 countries across the globe and sells well over 40 million pieces of diamond jewellery alone, the CSO is responsible for marketing about 80 percent of the world's rough diamond production, both of De Beers and other producers, in order to try to balance supply and demand and maintain stability in the market.

"If there is a downturn in the market," Nicky elaborates," "then we have to continue to purchase from producers - that's when we develop large stockpiles and that's really our task at the CSO, we're the squeezebox in between producers and consumers and consequently we can even out fluctuations in the market.."

The delicacy of the enterprise can be evidenced in the difficulties the industry experienced during the Depression of the thirties and again the early Eighties as Richard Dickson recalls. "There was massive oversupply in the marketplace so we completely cut back our supplies. In effect we acted as bankers to the industry. The irony is that right through this period, the demand for jewels at a retail level rose to record sales. The volatility was in the rough diamonds so we didn't drop our prices, rather we dropped our sales to about half what they were."

If it all sounds a little daunting, Richard agrees, "It is a complicated business but it works and we are dedicated to it and to maintaining adaptability and sometimes you have to take the 'hard decisions'. The De Beers group has shown itself to be both adaptable and to take the 'hard decisions'. Though the Second World War brought with it new technology, opening up a huge market for lesser quality industrial diamonds and enabling previously unimaginable advances in the cutting and polishing of gems, the 1950's heralded the discovery of a large mine in Soviet Siberia and saw successive African colonies achieve independence. The 1970's produced a new world player when rich diamond deposits were discovered in Botswana and the OPEC cartel sparked off rampant inflation in the West causing equally massive rises in diamond prices; the price of a rough stone had risen fourfold by that decade's end whilst polished stones were fetching astronomical prices.

The flamboyant William Goldberg's Premier Rose, a 137 carat dazzler created from a find at De Beers' own Premier mine, is a case in point. When sold in 1979, it fetched a staggering $10 million. The early 1980's also brought the discovery of what has become the world's largest source of diamonds, the Argyle Diamond Mines in Western Australia.

It was Harry Oppenheimer, together with his cousin Phillip, who were to meet these challenges, when they were handed the reigns of power upon the death of Harry's father in 1957. The changing times which were especially volatile in the region, saw Harry utilise his diplomatic skills and develop the chairmanship into a more statesmanlike role. As a South African politician who strongly opposed the introduction of the country's racial segregation laws, the 'Pillars of Apartheid', in the 1940's Harry complicated his dealings with the South African government but was consequently viewed in a favourable light, as was De Beers, by the leaders of the newly formed Africans nations. In response to the potentially debilitating diamond discoveries in Botswana, De Beers and the Botswana government reached an historic agreement in setting up a new company, Debswana, in which both partners had equal shares.

In the seventies, the CSO concentrated its marketing activities in the untapped Japanese market with enviable success and Japan has since become the world's second greatest consumer of diamonds after the United States. Richard Dickson elaborates: Unlike the Western nations where the tradition of the diamond engagement ring has been in existence since the fifteenth century, the Japanese have no such tradition but they have responded very enthusiastically to our advertising. They have the advantage of a very low crime rate in Japan and therefore it is possible for them to publicly display superior stones. They tend to prefer the higher quality gems and it's more likely you''' find one very good stone set in a ring." If that one good stone seems a trifle expensive it takes around 50 tonnes of kimberlite rock and expertise throughout several continents to produce a single polished gem.

As stated, polished gems were fetching astounding prices by the 1980's and the CSO attempted to curb the trend by introducing steep surcharges on its rough diamond allocations. Responding to the economic woes of the times, the CSO also reduced supplies whilst De Beers curtailed production and even reduced its share dividend. The harsh measures ensured De Beers and indeed, the industry as a whole, survived the recession and could meet the renewed demand of the mid-eighties. With Harry and Phillip having made way for their sons, De Beers now has its sights set firmly on the Nineties and any future obstacle that History will care to place in their path as they head the industry into the next millennium.

"The number of people now owning diamonds has increased greatly and this is very satisfactory to us," says Nicky. "In the distant past, diamonds were so rare that while they were immensely desirable, they were available only to a very small number of people. This has obviously changed with the discovery of diamonds in South Africa just over a century ago and more recently with the establishment of Australia's Argyle mine. What that has meant is that a major cutting centre like India has been able to widen its operation and a whole range of people who could never have previously afforded diamonds are now able to purchase them."

Despite their increased popularity diamonds are still a very rare, very precious commodity. "If you talk to our advertising people" jokes Richard Dickson, "they are very definitely a rare commodity. If, on the other hand, you consider that the world's total annual production is about 100 million carats, then of course you begin to think that perhaps they are not so rare. Given that about half that quantity are gem quality stones, it still sounds an impressive amount but if you look at those 50 million carats, by the time that they are cut and polished you are probably left with around 15 to 20% of the original. So, in polished gem terms you are looking at a fairly rare material and if you then consider the colour, quantity and size of the stones, the bigger and better ones are sounding very rare indeed."

Almost without pausing for breath, Dickson launches in to an equally effortless treatise on the selection of high quality diamonds. "A diamond is the product of billions of years of nature's magic, and is composed of a common carbon, not unlike the lead of a pencil, but time and large amounts of energy in the form of heat pressure crystallise the carbon into an octahedron shape, rather like two pyramids joined at the base. Volcanic activity millions of years ago, caused shifts in the earth's skins and plates formed about one hundred miles beneath the surface. Much later, again through volcanic activity, the diamond crystals sometimes surfaced, solidifying into a very hard bluish rock known as kimberlite or lamprite which we retrieve through open cast mining. Additionally, over the millions of years since all this occurred, erosion has gradually broken down this very hard rock, enabling diamonds to roll free and be washed into streams and rivers where they form alluvial deposit which are much more easily mined.

And of course as the exemption to the rule, the region around Namibia contains unique coastal deposits embedded in the sand,"The search for diamond deposits has become a high-tech affair, starting with satellite photography which magnetically indicates where diamonds are least likely to be found. Promising areas are then scanned with light aircraft and magnetometry and, to date, the richest deposits are concentrated in the Southern Hemisphere with Australia yielding the greatest quantities, followed by Zaire and Botswana, the U.S.S.R and South Africa.

Once the diamonds have been mined and separated from the rock, a process which itself incorporates the latest laser technology, they arrive at the London headquarters of the CSO to be sorted into over 5000 categories of shape, quality, size and colour. "Colour," explains Dickson, himself a former sorter adding that he managed to talk his way into public relations, "in a diamond is caused by the minute quantities of impurities in the stones. Nitrogen for instance, typically produces a yellowish colour or a discolouration in the carbon structure usually causes a brownish colour and from various combinations of these elements you get a variety of colours. Australia's Argyle mine produces an unusually high proportion of pinkish and purplish stones. More so than any other part of the world.

Every diamond, however remains unique, from the flawless ice-white stones given the ultimate 'D" and 'FI' classifications for colour and quality to the 'boart' those opaque, lustreless brown stones identified with much larger numbers and letters towards the end of the alphabet and so prized by industry, no two are ever alike. The sorting and classifying of the stones is executed by the CSO throughout the year in a series of five week cycles which culminate in the stones being inspected by the experienced eyes of the CSO managers and directors after which they are parcelled into their traditional shoe size cardboard boxes in a series of distinctively folded white envelopes which will be carefully studied by prospective buyers.

The CSO have a unique selling arrangement which has all the hallmarks of a sacred ritual and must be the envy of many businessmen. " We select our clients ourselves," states Dickson, "and we currently have about one hundred and fifty on our books. Three to four weeks before each 'sight', and these also take place every five weeks, we ask our clients to place an order, which we look at in addition to our own mixtures of rough stones as well as data on market activity and then we decide how much to sell them. We try to match their orders though this isn't always possible. The industrial gems are a different matter. They go to Ireland to be sold to industries through deals there but the gem material which is our forte is sold in London. This is where the manufacturers and cutters as well as the Winstons and the Graffs selected their gems. We offer them a range of over a hundred different mixtures and though we keep the size of the stones fairly constant we do group together various colours and qualities.

Having 'sighted' their allotted box and perhaps after some negotiation they will purchase the entire contents as we don't separate them. The larger stones are, of course dealt with individually as they are extremely rare to begin with. With these the price is open to negotiation."

Dickson picks up a rather ostentatious looking stone from a small display board. "This collection here," he informs indicating the handful of gems, "is worth about four to five million dollars on the retail market." As to the stone in his hand; In this larger stone you can see all these cracks and black spots so it wouldn't actually be worth what its size suggests. Although on the top there you can see quite a large healthy piece so it would be up to the cutter to decide how best to tackle the stone."

As it is quite common to lose between 50 to 70 per cent of a diamond in the cutting process, making the right decisions as to how to cut a stone can be a nerve-racking experience. "If you get it wrong you can lose your whole investment," offers Nicky before adding with a smile, "it helps concentrate the mind, does it?" Richard Dickson continues: "The finished gems' lustre and brilliance has a lot to do with the skills of the cutter and polishers in addition to the stones' inherent qualities. Cutting today has become much more of a science. The brilliant cut, for instance, is a much more lively cut, it reflects more and has less dispersion on the whole. In the end, however, it's also a matter of taste because some people prefer the warmth and softness of the older cut of stones"

There are, in fact, seven established cuts of diamond; the classic Brilliant, the cat's eye shape of the Marquise, the Pear-Shape, the Emerald, the Oval, the Heart-Shape, and the rectangular Baguette. To achieve these cuts the stones are either sawn against the grain, using a fine phosphor-bronze well and diamond powder or they are cleaved along the grain with a well-placed blow. The cut stone is then the ground with another diamond, as only diamond can cut diamond, and the traditional 58 facets are ground away using a rotating wheel faced with oil and diamond powder. This process has been perfected over the years in the four major cutting centres for the industry; New York, Antwerp, Tel Aviv and Bombay. "De Beers don't deal in cutting or polishing at all," explains Nicky. "A vast majority of the world's diamond flow through our hands so it would be very dangerous to compete with our own clients and, even though they may make a handsome profit on the stones they buy from us, we've taken a firm view that our business is the rough cut business. As to expanding our operations to include other gems we're in the best business. Diamonds seem to fulfill such a fundamental need in people that until something else comes along ...besides, the returns would hardly justify the effort."

Reflecting on the problems of such narrow specialisation he considers: "Our problem is that we are selling a luxury; the ultimate luxury, and economic circumstances do have an effect on sales. The Arabs, to cite one example, used to buy a lot of stones but since the oil crisis their spending has been severely curtailed. I might add this has made many jewellers in Geneva extremely nervous. Fortunately, De Beers itself is in a strong position. Through our partnership company, Debswana, the government of Botswana has five per cent stake in De Beers. The Oppenheimer family is, of course, a strong component, but overall we have a wide share base. There is even one share-holder in Finland who for twenty odd years has held only five shares. He's probably a jeweller who wants to get his hands on our annual reports!"

Whilst there is little doubt that De Beers will be able to overcome any threats from the Finnish contingent, the rarefied gentlemens' club atmosphere that prevails seems destined for the annals of time. Nicky is father to a son but Anthony has three daughters and given that the diamond business runs through the blood it won't be long before the executive decisions are taken by women. Anthony sees this as a welcome change. "It's absolutely right that the women do become involved," he enthuses. "After all, it's the women who buy the things. The men may think they're involved in the decision but they're absolutely wrong and the more women become involved in the industry the better it will be."

For the immediate future, the Oppenheimers are content to do what they do best; mine diamonds through De Beers and promote them through the CSO. Efforts in the Asia Pacific region in recent times have paid off handsomely. "The entire region is booming," beams a proud Richard Dickson. "We've been seeing exceptional growth, especially in Korea and Taiwan. In Australia, we've moved into print media to reach the whole market in a country where over 70 percent of women own a diamond engagement ring. That's one of the highest figures anywhere but you see only 30 per cent receive another piece of diamond jewellery in the first ten years of marriage so if we can encourage that trend it will be more likely they'll purchase a third piece."

The unsurpassed qualities of diamonds are also highlighted through such events as the biennial Diamond International Awards. As the industry's Oscars, they are a prestigious affair that showcase the genius of designers from around the globe as they reinterpret the notion of jewellery, using diamonds in myriad ways and both the awards and the winners are closely watched by the leading jewellery houses who seek additions to their own talented design teams. De Beers also sponsors countless local diamond awards throughout the world and assembles travelling exhibitions such as the 'Power of Love' exhibition which has been seen in London, New York and, more recently, Sydney. On display were sixty rings spanning six centuries, from the Renaissance to the present day.

Drawing on private collections from around the world as well as many fine pieces from respected local jeweller, Angus & Coote, the show was both a history of the celebration of love and a look at the changing fashions of the most desirable symbol of love, the diamond ring.

Yet the most effective and enduring message on the merits of diamonds was penned by a young woman in 1948. If, as Nancy Mitford observed, "The diamond is a stone possessed for the female mind, however unsophisticated, of curious psychological attributes," the copy writer who was given the task of creating a sales pitch must surely have been possessed by the magical gems when she simply stated: "A diamond is forever." Over forty years later, the immortal message remains the symbol of the eternal gem and last year a gala dinner was held to celebrate the fruitful partnership enjoyed by De Beers and N.W. Ayer the American advertising agency. Amongst the assembled guests of honour sat a graceful lady of a certain age. It was, of course, the same woman, the author of the four classic words which spell magic, and naturally her elegant gown was complemented by a dazzling array of diamonds.