Large ornamental copper plaque decorated with champlevé enamel in dark blue, sky blue, lapis lazuli, green, red ...

Large ornamental copper plaque decorated with champlevé enamel in dark blue, sky blue, lapis lazuli, green, red, yellow and white tones. Limoges. France. Romanesque. 13th century.
 
The plaque probably comes from an altarpiece. As it has a rounded format in the upper part, we can rule out its being the lateral fragment of a chest, as these always end in a triangle to fit with the upper part, which links each side in the shape of a roof. This makes our piece more interesting, as this type of plaques are rarer.  
In the central part, the appliqué figure is missing, which would certainly have been a saint, as the upper central ornamentation, which coincides with the place where the figure would have been, is in the shape of a halo. The initials A and B are engraved on both sides of this.  
Around the silhouette, we find different decorative elements of great chromatic richness, such as concentric circles, rosettes, four-lobed flowers and crosses.  
Similar examples to this one, although with the figure still affixed, and all originally part of altarpieces are, for example: 
The plaque of Santiago el Mayor dated circa 1231, which was donated by J. Pierpont Morgan in 1917 and is kept at the Metropolitan Museum in New York, with inventory number: 17.190.123. (https://www.metmuseum.org/art/collection/search/464004). 
The plaque of Saint Thomas, dated circa 1220 – 1230, which is kept at the Petit Palais, Musée des Beaux-Arts de la Ville de Paris. Inventory nº: ODUT1239(2) (https://www.parismuseescollections.paris.fr/es/node/221368#infos-principales) 
Finally, there is the one Marie-Madeleine Gauthier’s publication, with a probable provenance from the main altar of the church of Grandmont (Haute-Vienne and dated circa 1225 – 1230, which is currently kept in the Bargello Museum in Florence.  
Bibliography: “Émaux du moyen âge “. Marie-Madeleine Gauthier. Office du livre, 1972. Page 185, fig. 129. 
Measurements: 25,5 x 1255 cm.