The instrument head in this photo is a Peregrino di Zanetto viola (read about this instrument and maker at the link) that was made around the middle of the 1500s. The varnish appears to be original, and it also appears to have been applied with fingertips, not with brushes, as you can see by the fingerprints of color all over the surface. The body, too, has these prints, though many of them have been polished out and smeared more than on the back of the head, which is relatively fresh.