Russia's largest museum, boasting one of the world's richest art collections, announced the large-scale theft after a routine inventory check in late July. It said 221 items, worth an estimated 130 million rubles ($4.85 million), had gone missing from storage, including icons, medieval and 19th-century jewelry, silverware and enameled objects.
Earlier Friday the museum called on art and antique collectors to help find the exhibits stolen from its Russian section, which have been listed on the museum's official Web site.
"Today, a Moscow-based antique dealer found an 1856 chalice listed as No. 60 among the items stolen from the Hermitage," a spokesman for the agency said. "He voluntarily handed it over to the agency and waived his rights to the object, because it was stolen."
The art dealer said he had purchased the chalice in 2004.
On Thursday, an icon resembling an item on the Hermitage's list was found in a rubbish bin after police received a tip from an anonymous caller.
The Hermitage director has said members of staff were likely to have been involved in the theft, as only insiders had access to the museum's storerooms.
It remains unclear when the pieces went missing from the museum's Russian section, which contains about 300,000 works of art from Russia's thousand-year history. The curator in charge of the missing items died suddenly when the check that identified the theft began, Hermitage officials said.