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," says Carol Woolton, the jewellery editor of British Vogue magazine.
Signed, classic Art Deco Cartier or Van Cleef & Arpels pieces are among the most prized assets, she says.
"If you have classic vintage Cartier or Van Cleef pieces of the 1930s, signed, they will never drop in value."
Bentley & Skinner, a retailer in London's premier jewellery quarter on Bond Street, is renowned for its antique jewels, including some superb hand-crafted Victorian, Art Nouveau and Art Deco pieces.
Senior sales representative Stanley Lester says the credit crunch has not crimped spending, but footfall has eased off.
"Regular customers are spending a similar amount to before the credit crunch," he says. "Art Deco is without doubt the most popular. It never really went out of vogue. Victorian pieces are also extremely popular."
The focus on quality, design, craftsmanship and precious gemstones during the Art Deco heyday in the 1920s and 1930s was unparalleled, Bond Street jewellers say.
And it is now harder than ever to find the supremely precious Art Deco pieces, whether unnamed or branded, 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, says Francois Curiel, the chairman of Christie's Europe and international head of the jewellery department.
"More so today as examples from this period have become more and more difficult to find."
Van Cleef & Arpels, founded in 1906, is one of the oldest French fine jewellery houses.
Celebrated for its sophisticated, feminine designs and thorough craftsmanship, the Richemont unit says sales have held up despite the credit crisis.
"So far there has been no impact," says Geoffroy Medinger, the UK brand director of Van Cleef & Arpels. "We know that the big pieces never really stop selling because they are considered investments."
The firm's jewellery has the biggest turnover among estate jewels auctioned by Christie's and Sotheby's.
Curiel says the provenance of a jewel can greatly add to its value as an investment.
"An important diamond, coloured 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 says.
"In April 1998 we offered for sale in New York a sapphire and diamond flag brooch that previously belonged to Eva Peron." It was estimated at up to $120 000 and sold for close to $1 million. "The provenance had everything to do with it."
Like art, vintage jewellery moves in and out of fashion.
Bentley & Skinner has seen steady demand for rare Fabergé pieces, dating from the turn of the 20th century, particularly from Russian collectors seeking to reclaim their heritage.
"Demand has been fairly constant," says Lester.
Art Nouveau fine jewels from the late 19th century, bought mainly by women for themselves, are also much sought after. Victorian fine jewellery is hot because of its rarity and high quality.