Two pieces of ornate 16th-century armor have returned to the Louvre after a nearly four-decade absence. The elaborate breastplate and helmet were stolen from the renowned Paris museum on May 31, 1983, and then vanished for the next 38 years.

Forged in Milan during the Italian Renaissance between 1560 and 1580, the metal armor was inlaid with gold and silver and is estimated to be worth about $603,000 (500,000 euros), the Agence France-Presse (AFP) reported on March 3.

In January, a military antiquities expert spotted the armor after he was hired by an auctioneer for an estate auction appraisal in Bordeaux, France. He was suspicious about the armor's origins, so he notified officials with the French Central Office for the Fight against Trafficking in Cultural Goods (OCBC), a special police unit for tracking stolen property of historical and cultural importance. Authorities then identified the missing armor from a list maintained by Treima — an electronic database of stolen objects, Today24 News reported.

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France's Treima database contains approximately 110,000 photos linked to 32,000 open cases of stolen artworks and artifacts.

Intricate designs on the helmet and breastplate identify them as "prestige weapons made with virtuosity, sort of the equivalent of a luxury car today," Philippe Malgouyres, the Louvre's head of heritage artworks, told the AFP. The two pieces, which Malgouyres hailed as "exceptional," were donated to the Louvre in 1922 by the Rothschild family, one of the world's wealthiest banking dynasties during the 19th and early 20th centuries, according to Today24 News.

"I was certain we would see them reappear one day because they are such singular objects," Malgouyres told the AFP. "But I could never have imagined that it would work out so well — that they would be in France and still together."

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"I was certain we would see them reappear one day because they are such singular objects," Malgouyres told the AFP. "But I could never have imagined that it would work out so well — that they would be in France and still together."

The theft of the armor wasn't the Louvre's greatest art heist; in 1911, Vincenzo Peruggia stole the museum's famous Mona Lisa painting and managed to evade capture for two years, according to PBS.

As for how the Italian armor was stolen in the first place, that puzzle is yet to be solved, as the events of that long-ago caper are still shrouded in mystery, the AFP reported.

Originally published on Live Science.