A rare Raphael chalk drawing of a woman's head sold for a record £29.1 million, or $48 million, at Christie's in London – the highest price paid all year for a work of art at auction. In the same sale, Christie's sold a Rembrandt portrait that hadn't been seen in public for nearly four decades for a record £20.2 million pounds, or $33.2 million.

Raphael's "Head of a Muse" sold to an anonymous buyer for double its high estimate, a sign that collectors are willing to chase after older masterpieces even as global prices for living artists remain shaky. The work's price outperforms a Henri Matisse table scene that Christie's sold this spring for $46.5 million and an Andy Warhol screenprint of 200 dollar bills that Sotheby's sold last month for $43.7 million.

Raphael's black-chalk preparatory drawing depicts a serene figure with Cupid's bow lips that also shows up in the background crowd of one of the artist's seminal frescoes, "Parnassus." That mythological panorama of the god Apollo holding court on Mount Parnassus is one of four frescoes Raphael created around 1511 to adorn the Vatican library, Stanza della Segnatura. "Head of a Muse" is the artist's last example from the Vatican library commission still in private hands. (Other drawings tied to the same commission belong to the Louvre.)