In November, news broke that Graff is preparing an initial public offering in Hong Kong of his main asset, Graff Diamonds International.

FORBES: Laurence Graff

London-based jeweller Graff Diamonds is also reported to be planning a Hong Kong listing next year as it seeks to expand in Asia.

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Other assets include jewelry company Graff Diamonds International, a polished diamond trading company in Antwerp, a real estate company in Luxembourg and a stake in a South African diamond wholesaler.

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Behind this retail chain is a wholesale buying operation: Graff Diamonds International is vertically integrated, taking stones from the rough shapes that come out of the mine to the display case.

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Through Safdico, Graff now buys half of his uncut diamonds from the South African mining behemoth De Beers (Safdico is one of 93 sightholders, or wholesalers who are permitted to buy rough diamonds from De Beers).

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Prices for top-quality diamonds were up for the year, boosting Graff's net worth.

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In 2008 Graff achieved full vertical integration when he bought a stake in publicly traded diamond miner Gem Diamonds.

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