...Stephen Lussier. Here was a man who had studied psychology as an “undergrad” at Boston College. He had then spent thirty years in focus groups with young couples, finding out how they really felt. Under his tenure, De Beers has published its most outrageous adverts. On top of that, in 1996, Lussier married perhaps the most beautiful woman in England. There was plenty to learn.
     “The flip side of psychology is I think advertising,” he says. “You have the same techniques, the same statistics, the same one-on-one interviews and focus groups, techniques to get people to talk about what their thoughts are one level below the obvious. The best marketing works because it taps into something that people really want. It's not just because I've got a clever slogan, huh?”
     According to diamond historian Edward Epstein, NW Ayer had found that 85 per cent of all diamond jewellery was bought as a surprise. Yet in the majority of cases, somehow the woman knew. De Beers' consumers were playing out the courtship of a Victorian novel. If women were involved in the decision to purchase, they felt guilty and improper. Instead, they signalled approval. The man then plays out the role of dominant decision-maker and the woman remains blameless.
    NW Ayer called it the “gift-process continuum”. Lussier's own courtship, recounted in a column by Tatler, (reportedly) followed an identical model. And De Beers' loudest adverts were all published around the same time.
     De Beers took NW Ayer's idea and pushed it. Its adverts had become increasingly sexualised in the 1970s. Bare shoulders and a breathless chest were increasingly the diamond's backdrop. In the early 90s, Lussier took it to the max. “Of course there's a return on your investment,” one ad ran. “We just can't print it here.” Razor-sharp lines cut across a black background. Words like “Bigger” and “Prince” were set in large, white

print. The surprise of the diamond was alluding to the surprise of something else. The egotistical man remained ignorant and deluded, thinking the decision was his. The woman feigned delight. And De Beers encouraged them both. Its brand was all edgy and cool. Then the marketing era ended.
     “I think that ended with the power of the digital world,” Lussier says with slight regret. Where once brands could “dictate” their own message, digital giants have now “conditioned” the consumer “to get precisely what they want,

in their home, and find out all about it, in their own way. And if they order it at nine o'clock in the morning it should be there by two.”
    “Imagine the demand that puts on companies, and your total inability to control your message. It's very different than the old era. Now it's this extraordinarily fractured, complex world. It's much harder. It's much harder.”

     De Beers' market share has also plummeted. Diamond deposits were discovered in Russia in the 1950s, Australia in the '70s and Canada in the '90s. De Beers bought and sold Russian

production until 2004, but the diamond market has continued to fragment further. Three new companies have opened their first diamond mines in the last year alone. In total, De Beers' slice of the market has dropped from over 80 to around 30 per cent. Once all-dominant, it now has to compete with companies that weren't in business a decade ago.
     “The industry is now structured in a very, what I would call normal way,” Lussier says. “There are multiple producers, we compete against each other, as any industry would. So welcome to the normal business world.”
    The upshot for advertising has been profound. Having lost its sway over the market, De Beers was no longer willing to finance ad campaigns that also boosted its rivals. Instead, it launched its own high street brand, Forevermark, which De Beers has pushed instead. Founded in 2008, Forevermark boasts of its history “spanning more than 125 years”.
     Lussier has also moved in the background to form a new low-key association, bringing each of the world's diamond miners around one table. Its title, the DPA, is perhaps deliberately nondescript. Its initial budget of $6m was also widely derided, but has been quietly upped tenfold. Its objective is to promote “the diamond as a brand in itself”, says Lussier, as chairman of the DPA, re-instilling their romance in the mind of future consumers.
     He avoids bragging about it, but the new club is a feat of diplomacy. Russian diamond giant Alrosa is good at upping production, outflanking De Beers by carats mined each year, but has never previously spent a rouble on advertising. Now it is co-funding the DPA, to help out with some of the peddling. Smaller producers, from Vancouver-based Lucara to Petra Diamonds in London, have all also signed-up. “There are some things done best individually, but there are other areas where co-operation is both legal and beneficial,” Lussier says. “This is a perfect...