Flawless white or “colorless” diamonds may be the most sought after when it comes to engagement rings, but colored or “fancy” diamonds are far more rare and can be hugely more valuable. Where a one-carat white diamond may cost from $3,000 to $10,000, a pink, red or blue diamond of the same weight can easily sell for more than $1 million. In November, Laurence Graff, the London-based international jeweler, paid a record $46.1 million at Sotheby’s Geneva for a ring featuring a 24.78-carat fancy intense pink diamond, equivalent to $1.86 million a carat. The record price for a blue diamond at auction, $1.4 million per carat, is held by the Bulgari Blue, which sold in October at Christie’s in New York to an Asian buyer for $15.7 million. The top price for a red diamond was hit in November 2007 with a 2.26-carat fancy purplish-red diamond ring at Christie’s Geneva, which sold for the equivalent of $1.18 million a carat. Even relatively common yellow diamonds can outsell most whites. The top price per carat for a fancy vivid yellow diamond was achieved by a 13.83-carat marquise diamond, the Burden Yellow, which sold at Sotheby’s New York in 1997 for $3.3 million, or $238,612 per carat.
Although colored diamonds are extremely rare, the jeweler Lev Leviev has built a name selling some of the biggest in the world since opening his first Leviev store, in London, in 2006. Quickly adding three other stores — in New York, Moscow and Dubai — Mr. Leviev, who controls some of the largest private diamond mines in the world, then turned his eye to the fast-growing Asian market, opening a store in Singapore last year. Putting the store in the hotel lobby of the Marina Bay Sands, Leviev is targeting international clients, of course, but in particular the wealthy Asians drawn to the hotel’s casino. Asian clients, particularly the Chinese, have become an important force in the market, both for jewelry stores and in the auction rooms, where they bid enthusiastically for high-grade gemstones and jewelry, especially pieces featuring colored and large colorless diamonds.
Recognizing this growing demand for glittering jewels, several high-end jewelry companies are aggressively expanding in China. Van Cleef & Arpels added two outlets there last year, bringing its total to six. Laura Lai, the general manager for Van Cleef & Arpels’s in China, said in an e-mail that two more stores were planned for the summer. Tiffany & Co. has announced a major focus in China, with plans to double its stores in the country to 30 in four to five years. In October, Tiffany also unveiled its 2011 jewels and diamonds collections in Beijing, the first time the brand had offered a major new collection outside of its U.S. home market. 
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