In Romanesque art colourful champlevé enamel largely replaced it, although it continued to be used for small highlights of ornament, and some high quality Mosan art began to use it for small figurative images as part of large pieces, very often applied as plaques. These began to exploit the possibilities of niello for carrying a precise graphic style. The back of the Ottonian Imperial Cross (1020s) has outline engravings of figures filled with niello, the black lines forming the figures on a gold background. Later Romanesque pieces began to use a more densely engraved style, where the figures are mostly carried by the polished metal, against a black background. Romanesque champlevé enamel was applied to a cheap copper or copper alloy form, which was a great advantage, but for some pieces the prestige of precious metal was desired, and a small number of nielloed silver pieces from c. 1175-1200 adopt the ornamental vocabulary developed in Limoges enamel.