The only known surviving element from a Romanesque mirror case, this valve was originally slotted and joined by a clasp to a matching one. Mirrors of polished silver were fitted into the inner facings. The surface of the cast and chased case has been extensively worked to resemble champlevé enameling. The dragon motifs can be compared to those on the bowl of a drinking cup (acc. no. 47.101.31) and the knop of the Bertinus chalice ( acc. no. 47.101.30), both of which are also listed in this database. The foliate lugs and attached rings are modern additions.