The diamond dealers, many of them from Israel and India as well as Antwerp, enjoyed food on Sunday night prepared by a Michelin-starred chef as they listened to renowned soprano Ana-Camelia Stefanescu and the Nuove Musiche orchestra.

Many of the world's leading diamond dealers and manufacturers had assembled for the third edition of the Antwerp Diamond Trade Fair, from January 29-31, a key event for measuring the market outlook against this year's tough economic backdrop.

As light snow fell on Monday night, the dealers, manufacturers and jewellers, visited the MAS museum at Antwerp's port to see an exhibition about ancient civilisations around the world, followed by drinks and canapes.

The organisers also showcased the Belgian city as a vital point for the cutting, polishing and certification of diamonds.

Antwerp is battling for its place at the diamond high table against rising competition from India, which has many factories around Mumbai and Surat and lower labour costs, as well as Dubai, an increasingly important trading hub.

"We hope that this fair will strengthen Antwerp as an important centre for diamonds for years to come," Raphael Rubin, a senior official of the organiser, the Antwerp World Diamond Centre AWDC.L, told the elegant crowd at the dinner.

Some dealers toured the International Gemological Institute, a diamond testing laboratory located in the heart of Antwerp's diamond district, to see technicians working with microscopes to grade and certify gemstones.

Some eight in every 10 rough diamonds, and five in every 10 polished diamonds, pass through Antwerp, which has built its reputation as a leading diamond centre over centuries.

"We are reclaiming our position as the capital of rough and polished diamonds," Ari Epstein, CEO of the AWDC, said in an address to the gala dinner guests.

He said Antwerp authorities planned to announce a new strategy to safeguard the city's position as a diamond trade centre at a one-day event to be held on February 8, but gave no details.

Dealers attending the Antwerp Diamond Trade Fair voiced concerns that polished diamond prices may struggle to hold onto gains in the first quarter of 2012 due to worries over the global economy.

European demand for polished diamonds was slow as consumers were uneasy because of the euro zone debt crisis.

For the U.S. market, however, they talked of signs of improving demand after a good Christmas jewellery retail season.

Certified polished diamond prices rose in 2011, spurred by strong buying in the first half of the year, but global economic uncertainties caused prices to soften in the latter half.

For 2011 as a whole, the Rapaport Group's RapNet Diamond Index of prices for one-carat polished diamonds, a benchmark closely tracked by the industry, rose 19 percent.

(Reporting by David Brough)

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