Do you have any art deco jewellery at home? If you do, it seems to be enjoying a revival so it could be increasingly valuable.

Art deco jewellery is vibrant, bright and dressy, with a let's-go-party flamboyance. Dating from 1915 to 1935, it is angular and sharp, typified by strong colours and often features white diamond contrasted with black onyx - a shiny gem stone.

Mr Thomas Murtagh, a retired dealer who appeared on the antiques slot on RTE's Live at Three programme for 11 years, used to sell quite a bit of art deco jewellery. "Art deco has a following all of its own. With genuine stones, it's fairly expensive. There is a strong demand for it. It's going through a bit of a renaissance at the moment."

Art deco watches tend to be square and sharp, set with precious stones like rubies or sapphires. Dress rings in the style can be "hard and harsh looking" with very heavy gold bands, he says.

Mr David Lancaster, head of the jewellery department at Christie's South Kensington in London, says art deco jewellery was a reaction to the very soft, subtle curvilinear pieces which preceded the first World War. After the war, jewellery became more harsh, angular and geometric.

This was an effect of the war. "Women changed their roles. They did an awful lot of mechanical work during the war. They worked in munitions factories. So things hardened and became a bit more vibrant.

"There was this sense of having survived the war and wanting to express oneself and be bright. So there were some strong colours and shapes. It was mostly white. You get the sapphires and rubies but a lot of diamond. And also quite a bit of rock crystal coming in - quartz - which can give the effect of a diamond floating in air," he says.

Fashionable art deco jewellery wasn't ever cheap, but cheap costume jewellery followed, made in the art deco style. Moreover, not all pieces from 1915 to 1935 are done in the art deco style. Standard mainstream jewellery continued to be made. "So it's not only period. It also has to have that style, that flamboyance," says Mr Lancaster.

Diamond and gem art deco jewellery should fetch "anything from £500 through to many thousands of pounds, depending on what it is and who made it", he says.

The best pieces are probably French and made by houses like Cartier, Van Cleef and Arpels, and Boucheron. Cartier specialised in very strong onyx and diamond - "very strong geometric brooches".

If you had a Cartier black and white art deco jewel, signed and in its original case, it would be "an extremely desirable collector's piece". Such an item should be worth at least £5,000.

Art deco jewellery is all the more valuable because it is increasingly rare. Much of it was broken up - with the gold being melted, the stones recut and used again - when fashions changed.

Christie's recently sold a pair of Van Cleef and Arpels clip brooches which fetched in the region of £8,000 sterling. A Cartier art deco pendant watch fetched £1,800 sterling. But even unsigned pieces can fetch high values.

"If it's got strength of design, then it's still desirable." Last May, a set of four French enamel clip brooches in a fitted case, fetched £1,100 sterling (estimate of £400-£600 sterling). An unsigned art deco diamond and onyx ring sold for £900 sterling (estimate £600-£800 sterling).

An art deco diamond panel brooch, which was "basically all diamond but with just a touch of black enamel in the centre to give the contrast" sold for £4,500 sterling. And a "small but pretty" unsigned art deco ruby and diamond twin cluster clip brooch made £1,000 sterling.