A diamond cartel is for ever; Oppenheimers nearly so. Periodically the death rattles of the cartel, which sets prices for most of the world's uncut diamonds, are said to be heard.
In 1905 it was synthetic diamonds. In 1942, Roosevelt's anger. In 1960, Russian finds. In 1977, Israeli hoarding. In 1983, Australian finds and Zaire's defection. Each time, the cartel outwitted fate.
It has different names, but the cartel is De Beers and De Beers, like Anglo American, is the Oppenheimers.
Now the third generation is officially in charge. Nicholas Frank Oppenheimer, 53 - also known as Nicky, or the Cuban because of his beard - became chairman of De Beers a year ago. He is not having an easy time. Last month the company announced that because of falling Asian demand, it sold fewer diamonds than it had for 12 years, a mere $3,4 billion worth.
In company lore, Oppenheimer's grandfather, Sir Ernest, was the daring entrepreneur; his father, Harry, the philosopher king. And Nicky is - well, something different.
He wears funny socks and is relaxed enough to be photographed pounding an African drum with miners at a company ceremony. At the same time, he negotiates billion-dollar deals with the Russians. "It's much nicer to be known as Nice Guy than Nasty Guy," he jokes. "But you've got to have lines. And when you hit the line, that's the end of the story, nice guy or not."
In London Oppenheimer commutes by helicopter, which he pilots. In South Africa he has his own cricket team and stadium. In return for a donation to youth cricket, his team gets the first match with visiting national teams.
In public Oppenheimer often pokes fun at himself. His obligatory military service in the 1960s, he says, was spent as second-in-command of a parking lot near Pretoria, signing vehicles in and out. "The army taught me to sign my name very quickly, and that's stood me in good stead the rest of my life."
His own personality is in stark contrast to the ruthless reputation of the cartel's Central Selling Organisation (CSO) in London, which buys an estimated 70 percent of the world's rough diamonds.
The CSO is still capable of freezing out diamond dealers who cross it. But Nicky Oppenheimer has brought warmth to the business, running the CSO since 1985 in a way very unlike that of his icy uncle Phillip.
Nicky is, for example, not afraid to admit that diamonds are intrinsically worthless "except for the psychological need they fill". Nor does he mind calling a cartel a cartel, though he prefers "single-channel marketing".
And he views with wry amusement the fact that he cannot visit the US, by far the company's biggest market, because of a legacy of unresolved antitrust cases.
He has been there in the past to ski and to see relatives, but since an indictment charging De Beers with fixing the prices of industrial diamonds more than four years ago, no De Beers director will enter the US for fear of being subpoenaed.
"It's a strange thing," he says. "Here I am a believer in free enterprise and competition, all the good liberal values, and yet I'm chairman of a business which talks ultimately about single-channel marketing, control, all those sort of things."
At the moment he is reorganising the De Beers-Anglo-Minorco consortium into Anglo American plc. He denies what some analysts say: that the planned move to London is a way for Anglo to improve its image in the US.
As a result of the reorganisation, hundreds of De Beers workers on the Anglo payroll are being shifted back to De Beers. And De Beers has moved its head office out of Anglo's Johannesburg headquarters to Gold Reef City.
But the cross-ownership between De Beers and Anglo is not being undone, nor is the Oppenheimer stake in both, Oppenheimer says. De Beers still owns roughly 40 percent of Anglo, essentially as a cash cow and as collateral for the billions it must borrow to get through bad diamond years. To keep diamond prices rising gently, De Beers must buy and hold raw stones. When jewellery demand sinks, that is expensive.
Oppenheimer says it is "rubbish" that the family controls both De Beers and Anglo, because it "directly owns" only 8 percent of Anglo - the family line for decades. He is also the non-executive deputy chairman of Anglo, while his son Jonathan, 27, is rising through the Anglo ranks in Zimbabwe.
While professing no interest in politics, Nicky enjoys good relations with the new government. He is on the board of Nelson Mandela's Children's Fund and he signed the deals that arranged for black ownership of substantial portions of two Anglo subsidiaries, Johnnic and JCI.
"There were many years in the 1980s when there was absolutely no contact between Anglo and De Beers and the government," Oppenheimer says.
"With the present government, things have finally become normal. One feels the government is doing what it should in supporting business endeavours, and that's extremely healthy." - The New York Times