Restoration of the altarpiece of Saint John the Baptist of the Convent of the Discalced Trinitarians

The altarpiece had various deficiencies that prevented an adequate reading of the work, such as a widespread dirt due to dust and deposits of biological origin, oily fumes and environmental pollution.

He also had a widespread repainting, marbled in ochre and white tones, which was spread over much of the surface and hid the original, higher-quality polychrome. On this overpainting, there were remains of oxidized varnish and some specific traces of another polychrome. Upon removing the overpaint, original polychromy defects, caused by cracks between pieces of wood or by knocks and detachments.

It had some non-original added elements such as the altar table, the staircase frontals and the niche panels.

Prior to the restoration, pieces at risk of detachment from both the painting and sculpture were collected and identified. Solubility tests were conducted to determine the techniques and materials to be used in the various stages of the work's restoration:

• Surface and chemical cleaning. Removal of oxidized varnishes
• Removing repaints respecting the original, ensuring its reversibility and protecting the adjacent areas where the polychrome was original, to prevent wear, friction, or minor abrasions caused by handling. The overpainting was removed mechanically, using a scalpel.

• Saturation of the polychrome layer by means of surface impregnation, imitating hard stone.
• Volumetric reintegration of lagoons with a special resin, in a way that imitates and is discernible with respect to the original. It has then been sanded, seeking textures similar to the original, leaving the area ready for the chromatic reintegration.
• Final protection with varnish application with a satin finish that imitates hard stones to restore the initial compactness and porosity and achieve a realistic appearance, just as the authors of the work intended.