The marble

Various types of marble are used by the masons commissioned to build the tomb. The dark red Adnet marble – named after its place of origin near Hallein in Salzburg - is particularly favoured at this time and is used by Dutch sculptor Niklas Gerhaert van Leyden for the lid of the tomb. Adnet marble is in fact limestone, not marble, and is so difficult to form that van Leyden takes 5 years to complete Frederick’s portrait on the lid. Was Frederick inspired by the red marble sarcophagus of Constantine the Great and his mother Helena that he saw in Rome at the time of his coronation by Pope Nikolas V? Maybe.