The Martyrdom of Saint Agnes

This
  small monochrome canvas is traditionally considered to be a sketch or first
  draft for the altarpiece with the "Martyrdom of Saint Agnes",
  commissioned in 1590 for Milan cathedral and completed in 1592 (now in the
  Borromeo collection) which was the first important public work in Milan by
  Camillo Procaccini. The
  finished nature of the small monochrome painting, however, suggests an
  independent work, destined for a private collection - a hypothesis supported
  by the fact that two other versions of the same painting are known.