A drawing that was owned by the University of Reading has been confirmed to be a work by the 17th Century artist Sir Peter Paul Rubens, who was one of the most influential Baroque artists in northern Europe.
The 4.25in by 3.5in sketch of the Marie de Medicis has been valued at 75,000 pounds, the BBC reported.
The exceptional piece of art was bought in the 1950s for 50 pounds and was thought to have been drawn "in the style" of the Old Master.
Professor Anna Gruetzner Robins, from the university's art department, termed this an "extremely exciting discovery".
Explaining about the painting Prof Robins said, "[This sketch] belongs to a group of portrait drawings of Marie de Medicis made circa 1622... all of which were studies for 21 life-size paintings representing Marie's life from her girlhood, coronation as Queen of Henry IV of France, to old age and exile.