The upper paint layer of the draperies of this female saint has faded. The brown-ish yellow lines we can see are called sinopia – these show the initial design or drawing of the fresco. Small traces of green-blue paint – some only visible through a microscope – are probably a pigment known as azurite, revealing that her robes were originally blue. The Virgin Mary is usually shown wearing a blue mantle and the way in which she recoils, drawing her hand to her breast, and the fearful expression in her eyes, recalls images of the Virgin at the Annunciation, when she receives the frightening and unexpected news that she will bear the Son of God. Alternatively, she might be one of Jesus’s female followers, mourning at The Crucifixion – one of the scenes that survives in the chapter house of the convent church of San Francesco, Siena, where this fresco fragment came from.

Pietro Lorenzetti, with his brother Ambrogio, decorated several important religious and public buildings in Siena with frescoes. Apart from A Group of Four Clares and A Crowned female Figure (Saint Elizabeth of Hungary?), other frescoes in the chapter house were The resurrected Christ and The Crucifixion, both painted by Pietro. His brother Ambrogio painted a further two: Pope Boniface receiving Louis of Toulouse as a Novice and The Martyrdom of the Franciscans. The cycle of images may also have included The Stigmatisation of Saint Francis – the moment the saint, in prayer, received the wounds of Christ, caused by the nails of the Crucifixion.

The figure is framed by a stepped and curved outline, probably part of a barbed quatrefoil shape. Only part of it is visible, suggesting that the saint, like A Crowned female Figure (Saint Elizabeth of Hungary?), was part of a border consisting of figures placed within decorative shapes, surrounding a larger scene. The halo is raised slightly above the surface of the plaster and it has been carved with deep incisions, probably to make it visible from a height so it must have come from the upper part of the border. The quality of the painting is not quite as high as his fresco showing A Group of Four Clares but border figures like this were probably delegated to workshop assistants.

The fragment was purchased by the archaeologist, diplomat, MP and National Gallery trustee, Sir Austen Henry Layard. As a member of the Arundel Society, created to document and preserve Italian frescoes, he was interested in fresco as a medium. Layard claimed that he bought these fragments ‘from a man who had cut them out of the wall’ but he mistakenly thought they had come from the church of S. Agostino in Siena.