- Technical and restoration study on the collection of Miniatures in the Museo del Prado
- Restoration of the collection
Restoration of the collection
When deciding to restore the Museum's collection of miniatures, the aim was that of conservation and for this reason no repainting or replacement of materials was carried out. Instead, the restoration process focused on stabilising the works through the elimination of products and materials that affected or destabilised their state of conservation. In most cases this related to adhesives, pieces of card or frames that had produced deterioration or tensions.
The restoration of the Portrait of a Man (O-813) offers an example of the excessive presence of adhesives and poor handling. The work had dark patches on the face and adhesive tape stuck on the paint surface and on the back fig. 31. When removed from the frame it was observed that it had two pieces of yellowed paper stuck on with old, brittle glue. These pieces of paper were removed, revealing behind them the silver leaf crudely stuck to the ivory. The silver had corroded due to contact with the adhesive and was brittle and dark, resulting in the dark areas visible on the face fig. 32. The silver leaf was removed and traces of adhesive removed from the back of it, at which point the face recovered its original flesh tones. In the case of the mark left by adhesive tape on the paint, the remains of the adhesive were removed mechanically with a binocular lens in order to clean up the paint layer but this zone lost some of its precision fig. 33. In order to recover the effect of the sheen of the silver leaf a piece of aluminium film was inserted as this is more stable and has the same metallic sheen. It was attached to an acid-free piece of card that was used as a backing when the miniature was replaced in its frame fig. 34.
A comparable case was that of Portrait of a Man (O-799) by Antoinette Brunet. The sitter's face had become dull and yellowish fig. 35. As in the previous case, it was found that the silver leaf and pieces of paper had been stuck to the ivory. They were removed and the adhesives cleaned off but in this case they left the ivory with a yellowish tone in the area of the face, as a result of which the sitter still had a sickly appearance fig. 36. Removing the stain on the inside of the ivory would have required an aggressive intervention and it was therefore decided to make use of its transparency. A piece of tinted red card was inserted as a backing that counteracted the yellowish tone. As a result, the sitter recovered his healthy, pink appearance with a minimum degree of intervention fig. 37.
Another interesting procedure, in this case an old one, had been used on Portrait of a Lady in black (O-690). The portrait was extremely delicate but the dress and background were very thickly painted to the extent that the paint layer had craquelure. It was also curious that this miniature had silver leaf in the zone of the bust when this was covered over by a black shawl. An x-ray of the work and subsequent analysis revealed that this miniature had been 'dressed in mourning' as the sitter originally wore a lighter dress fig. 40, but a family death or the fact that she had been widowed had resulted in mourning dress being painted onto her, concealing the original paint with this thick black garment .