The Complex Conservation of Picasso's Guernica

The journey of Picasso's Guernica is as tumultuous as the history it depicts. Dora Maar's photographs captured the evolution of the painting, revealing Picasso's iterative process. Modern infrared reflectography now allows us to see beneath the layers, uncovering Picasso's adjustments, such as the repositioning of the soldier's head and the hidden eyes in the bull's head.

The painting's physical condition tells a story of its own. Frequent relocations have left the canvas with significant wear and tear. The original stretcher, used until 1964, lacked tensioning systems, leading to edge deterioration and numerous tears and holes.

Handling and rolling have caused craquelures and fissures in the paint layers. These damages vary in severity, with craquelures being more serious, affecting multiple layers, and often linked to thicker paint areas.

A 1957 restoration at MoMA involved applying a wax-resin mixture to stabilize the paint layers. This method, while consistent with the era's practices, was irreversible and left wax residues visible under ultraviolet light.

In 1974, the painting was vandalized with red acrylic spray paint. Thanks to a protective varnish applied in 1962, the red paint was removed without harming the original. However, microscopic red residues remain, nestled in the painting's fissures.