Multianalytical characterization of priming in Hayez paintings.

The priming and ground layers of a painting have several roles in its making, and they must satisfy both artistic and conservation issues. The study of primings in Hayez works allows evidencing such aspects, as their structure and conservation state appear quite various. Occasionally, degradation aspects of the priming and canvas were also observed. In this work, we present an accurate characterization of the priming of several paintings by Hayez, chosen over a time span (1812-1879) covering most of his career. The analyses were carried on by optical spectroscopy techniques (FTIR, Raman), scanning electron microscopy and X-ray energy dispersive spectroscopy. The study shows an extreme variety in the priming used by the artist. While the main components of the layers of the primings are usually white lead, barite and calcite: their concentration along the thickness (between 100 and 500 microns) of priming may change considerably. According to number of layers, composition and grain size at least five different preparation methods for the canvas were recognized. Their effect on the conservation of the paintings is discussed.