FLORENCE, ITALY - A painting by Italian Renaissance artist Raphael that hasn't been displayed publicly for over 40 years was sold at auction Thursday for $37.2 million.

The portrait of Lorenzo de' Medici, a member of Florence, Italy's royal family, had been in the private collection of an American art dealer for almost half a century.

Auctioneers at Christie's in London had expected the painting to go for an amount between $20 million and $30 million.

The portrait was sold to a private collector bidding by telephone.

"There are very few Raphael paintings that remain in private hands," Christie's spokesman Matthew Paton said. "We probably won't have another Raphael again for a lifetime."

Finished in 1518, two years before Raphael's death, the painting features Lorenzo de' Medici elegantly dressed  in gold and red brocade with a delicate fur trim in front of a dark green background.

Painted on canvas - something Raphael rarely did because he preferred to paint on panels - the portrait is in perfect condition, Paton said.