Fifteen of the 26 pieces loaned by private collectors for an Erte exhibition in Rome are missing, curator Francesco Maria Messina announced at a news conference Tuesday.
"The external packaging of the box we received was intact. But when we opened it, we saw that a smaller package inside had been tampered with and almost all the jewelry was missing," Messina said, according to the ANSA news agency.
He said investigators believe the theft took place before the package reached Italian customs. Judging from the way the wrapping was torn, it appeared the thief was in a hurry, Messina said.
Anna Santi, a museum spokeswoman for the museum, later said it is unclear exactly what happened, but insisted the problem was on the other side of the Atlantic, where the jewelry was packed. "It's a matter of American competence," she said.
The exhibit, which opens to the public on Wednesday, features 180 pieces, including furniture, gouache and sculpture, by the Russian-born fashion illustrator and costume designer Romain de Tirtoff.
De Tirtoff, who was known as Erte, enjoyed his heyday in Paris in the 1920s. He died in 1990 at the age of 98.
Among the pieces that are missing, "Foxes," a delicate gold necklace with stylized fox heads, encrusted diamonds and other precious jewels, and many pins, rings and earrings.
The remaining items going on display at Tuesday's opening include "Soleil Noir," a pearl and diamond ring, and golden earrings known as "Cascade III."
Museum officials gave no estimate on the value of the stolen jewelry.
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