What the Heck is Gesso and Polychrome anyway?

Gesso was commonly used as a ground or primer on antique furniture and other decorative objects made of wood, plaster, or metal. It was applied to the surface to provide a smooth, even base for paint or other decorative finishes.

Polychrome refers to the use of multiple colors, typically in a decorative or ornamental way. In the context of antique decorative objects, polychrome refers to the use of multiple colors to create intricate and ornate designs. This could include painted details, gilded or gold leaf accents, or the use of different colored woods or materials to create patterns or designs.

For example, gesso and polychrome were often used together on antique wood furniture to create intricate painted designs or to highlight carved or gilded details. Gesso would be applied to the surface as a base, and then multiple layers of paint in different colors would be applied on top to create the desired design. Similarly, gesso and polychrome could be used on plaster or metal objects to create decorative finishes.

Throughout medieval Europe religious sculptures in wood and other media were often brightly painted or colored, as were the interiors of church buildings. These were often destroyed or whitewashed during iconoclast phases of the Protestant Reformation or in other unrest such as the French Revolution, though some have survived in museums such as the V&A, Musée de Cluny and Louvre. The exteriors of churches were painted as well, but little has survived. Exposure to the elements and changing tastes and religious approval over time acted against their preservation. The "Majesty Portal" of the Collegiate church of Toro is the most extensive remaining example, due to the construction of a chapel which enclosed and protected it from the elements just a century after it was completed. (1)

1.  Katz, Melissa R. Architectural Polychromy and the Painters' Trade in Medieval Spain. Gesta. Vol. 41, No. 1, Artistic Identity in the Late Middle Ages (2002), pp. 3–14