Rare vintage jewels are increasingly popular investments to protect against rising inflation and economic uncertainty, and art deco designs are commanding the most attention from collectors.

"There are a lot of people now with jewels in their safes for a rainy day," said Carol Woolton, Jewellery Editor of British Vogue, a top fashion and lifestyle magazine.

Signed, classic art deco Cartier or Van Cleef & Arpels pieces are among the most prized assets, she said.

"If you have classic vintage Cartier or Van Cleef pieces of the 1930s, signed, they will never drop in value."

Bentley & Skinner, an established retailer in London's premier jewelry quarter on Bond Street, is renowned for its antique jewels, including some superbly hand-crafted Victorian, art nouveau and art deco pieces.

Senior sales representative Stanley Lester said the credit crunch had not crimped spending, although customer traffic had eased off.

"Regular customers who come in are spending a similar amount to before the credit crunch," he said.

"Art deco is without doubt the most popular. It never really went out of vogue. Many Americans are looking for jewellery of the art deco period. Many customers are looking for art deco engagement rings and Victorian pieces are also extremely popular."

The focus on quality, design, craftsmanship and precious gemstones during the art deco heyday of jewellery design in the 1920s and 1930s was unparalleled, Bond Street jewellers say.

And these days, it is harder than ever to find the supremely precious art deco pieces, whether branded or unnamed, which pushes their value higher.

Investors are scouring collectables markets for assets that will hold their value against rapidly rising prices, and antique jewels fit the bill because of their intrinsic beauty and increasing scarcity.

Vintage jewels especially from the 1920s from houses such as Black Starr & Frost, Boivin, Boucheron, Bulgari, Cartier, Janesich, Lacloche, Mauboussin, Raymond Yard, Sterle, and Van Cleef & Arpels, have always had a strong following, said Francois Curiel, chairman of Christie's Europe and international head of the jewelery department.

Van Cleef & Arpels, founded in Paris in 1906, is one of the oldest French fine jewellery houses, based on the Place Vendome.

Celebrated for its sophisticated, feminine designs and thorough craftsmanship, Van Cleef & Arpels, a unit of luxury group Richemont and now present in some 70 locations around the world, said sales had held up despite the credit crunch.

"So far there has been no impact," said Geoffroy Medinger, brand director UK of Van Cleef & Arpels on Bond Street. "We know that the big pieces never really stop selling because they are considered investments."

Van Cleef & Arpels jewellery represents the biggest turnover among estate jewellery pieces sold by the auction houses Christie's and Sotheby's. Curiel said the provenance of a jewel can greatly add to its value as an investment.

"An important diamond, colored gemstone, or jewel will always fetch market price but that plus a noteworthy provenance could change the value of a jewel tenfold or more," he said.

"In April 1998, we offered for sale in New York the Argentine sapphire and diamond flag brooch that previously belonged to (former Argentine first lady) Eva Peron with a pre-sale estimate of US$80,000-120,000. It sold for close to US$1 million and the provenance helped."

Besides art deco designs, art nouveau fine jewels, dating from the late 19th century, are much sought-after and Victorian fine jewellery is hot because of its rarity and high quality.