The New York Times declares Art Deco jewelry a good investment and explains why:

Art Deco jewels, characterized by their clean cut and overtly angular design, have continued to perform well at auctions in recent years, “even at a time when the market is not at its best,” said Francois Curiel, President of Christie’s Switzerland and Chairman of Christie’s Asia.

That is mainly because there is very little of it left on the market. Many art deco pieces were broken up after World War II, as the style went out of fashion and owners re-used the stones in new settings: “So, what’s left today brings extremely high prices,” Mr Curiel said.

At Christie’s Geneva auction on May 12, a multi-colored ‘Tutti Frutti’ bracelet of the Art Deco period sold for just over 1 million Swiss francs, or about $880,000, well above its 160,000 franc to 210,000 franc estimate. Other rare Art Deco pieces also performed well. A “Camelia” brooch, designed in about 1926 by Jeanne Boivin, the sister of the renowned French couturier Paul Poiret, sold for 159,000 francs against an estimate of 32,000 francs to 42,000 francs while a 1933 pair of “Coquillage Ailé” ear clips, shaped like winged shells, also by Ms. Boivin, sold for 68,750 francs against an estimate of 14,000 to 18,000 francs.

Rarity of Art Deco Work Keeps Prices Buoyant (New York Times)