Italy made good on its agreement to loan one of its treasures to the Museum of Fine Arts on Tuesday, turning over a 9-foot marble statue Eirene -- goddess of peace -- in exchange for the Boston institution returning 13 disputed antiquities to Rome this fall.

The statue dates to the first half of the first century and, like many Roman sculptures, is an adaptation of a Greek sculpture. The original bronze sculpture of the personification of Peace, holding the baby Ploutos, was made by Kephisodotos and dates to the 370s or 360s B.C.

The statue -- which no longer has its arms or the infant -- was excavated in 1986 from the garden of a Roman villa in the territory of Palombara Sabina. It will be on view to the public until 2009.

"Experts say this is the most beautiful existing copy in the world," Italian Culture Minister Francesco Rutelli said at a news conference following the unveiling of the statue. "I would say you gained. It's the symbol of peace."

MFA director Malcolm Rogers called the selection "very symbolic."

"It was found in a farmer's field," Rogers said, noting that the plow marks are visible on the back of the statue. "It could have been looted. Instead, the site became an archaeological site. This is a wonderful statue symbolizing what happens when the circumstances are right."

In Italy, the head of Eirene and the torso had been displayed separated, but conservators at the Boston museum have joined the two pieces together for display for the first time.

"The whole thing that makes this statue so expressive and slightly mysterious is the turn of the mother's head to the child which is no longer there," Rogers said. "Unless you have the head in position, you really don't get this emotional and this affectionate aspect of this statue."

Another copy is on display at the Glyptothek in Munich. That copy includes the infant. A photo of it is posted on the Eirene statue at the MFA. Rogers said it's impossible to know who made the copies because few Roman statues are signed.

Italy has been on a campaign to recover antiquities allegedly sold illegally to museums worldwide. Officials have reached a similar deal with New York's Metropolitan Museum of Art but are in dispute with the J. Paul Getty Museum in Los Angeles.

Italy has demanded the Getty return more than 40 works. The museum last week agreed to return 26 allegedly looted antiquities, a move Rome called unilateral and inadequate.

Italy's campaign includes the prosecution of former Getty curator Marion True and art dealer Robert Hecht, who are on trial in Rome charged with knowingly receiving archaeological treasures stolen from private collections or dug up illicitly. They deny wrongdoing.

Under a 1939 law, all antiquities found in Italy must be turned over to the state.

The MFA returned artifacts including a statue and a bas-relief believed to have decorated Hadrian's Villa outside Rome, and vases from central and southern Italy mostly depicting scenes from ancient Greek myths.

Boston's antiquities were the first to be delivered to Italy, and were exhibited in October at the National Roman Museum. Those included in the Met deal are set to return progressively over the next years.

Rogers has said the treasures were purchased in good faith between the 1960s and 1990s, but the antiquities were returned after Italian authorities presented fresh evidence of their illegal origin during yearlong negotiations.

"At the very moment it was clear that some of the objects here had to be returned to Italy, you have done it," Rutelli told Rogers at the news conference. "That shows... a very clear moral authority."