Madonna and Child with St. Justus of Volterra and St. Margaret of Antioch.

Bastiano Mainardi's Madonna and Child with St. Justus of Volterra and St. Margaret of Antioch, dated 1507 and now at the Indianapolis Museum of Art, is a sacra conversazione panel that reveals his independent activity as a mature painter beyond the Ghirlandaio workshop. Saint Justus of Volterra was a local Tuscan martyr whose cult was centered in the Volterra diocese, suggesting this painting may have been commissioned by a patron from that area or a church under Volterra's ecclesiastical jurisdiction. Saint Margaret of Antioch — one of the most popular female saints of the medieval church, patroness of women in childbirth — would have had particular devotional significance for female patrons or women's religious communities. Mainardi's composition follows the standard Florentine sacra conversazione formula while reflecting his own modest but assured command of the format inherited from Ghirlandaio.

Mainardi employs the Ghirlandaio workshop technique of clear structural drawing and warm, even illumination, with figures grouped in the standard triangular sacra conversazione arrangement. The saints' attributes — Justus's palm of martyrdom, Margaret's dragon — are rendered with precise iconographic accuracy, and the landscape background shows the Florentine convention of atmospheric distance softening into blue hills.