On the technical side, the Art Nouveau saw the great use of beautiful Enameling Techniques in jewelry, such as cloisonné (in which gold wire forms partitions into which the enamel is poured); champlevé (in which the enamel fills recesses cut out from the background metal); basse-taille (in which an engraved design in the metal is covered with, but still visible through, a transparent enamel);and plique-a-jour (in which the backing metal is removed from the translucent enamel after firing, resulting in a stained glass effect).