plique-à-jour

thumb|The Mérode Cup, the surviving medieval piece in plique-à-jour, c. 1400 thumb|upright|Plique-à-jour enamel with small rose-cut diamonds in the veins c. 1900 thumb|Bowl with plique-à-jour enamelling on a silver base. The silver has been cut into a pattern of stylized waves with floating chrysanthemum blossoms. By Namikawa Sōsuke, Meiji era, c. 1900

Plique-à-jour (French for "letting in daylight") is a vitreous enamelling technique where the enamel is applied in cells, similar to cloisonné, but with no backing in the final product, so light can shine through the transparent or translucent enamel. It is in effect a miniature version of stained-glass and is considered very challenging technically: high time consumption (up to 4 months per item), with a high failure rate. The technique is similar to that of cloisonné, but using a temporary backing that, after firing, is dissolved by acid or rubbed away. A different technique relies solely on surface tension, for smaller areas. In Japan the technique is known as shotai-jippo (shotai shippo), and is found from the 19th century on.