Canvas as a pictorial support was only reluctantly adopted in Rome and even in the 17th century it was not universally employed. From 1530 until the first decade of the 17th century, many altarpieces in Rome were instead painted on stone, especially on slate. The invention of the technique is due to Sebastiano del Piombo (1485-1547) who employed it in his monumental Nativity of the Virgin for the Chigi Chapel in Santa Maria del Popolo. The itinerary presents a selection of the most significant stone altarpieces in Rome: San Marcello al Corso (Federico Zuccari), S. Maria della Vallicella (Rubens) S. Caterina dei Funari (Girolamo Muziano), San Silvestro al Quirinale (Scipione Pulzone), Santa Maria della Pace (Lavinia Fontana), Santa Maria Maggiore (Girolamo Siciolante) are among the churches a included in this guide.