AN INTRODUCTION TO ENAMELLING PLIQUE A JOUR page 1 The distinguishing characteristic of plique-a-jour is that the finished piece has no metal backing to the enamelled areas; this allows light to pass through the transparent or translucent enamel. The three main methods of constructing a plique a jour piece are:
1) PIERCING - sawing, drilling, filing, punching, stamping, etching or otherwise making small holes of various shapes and sizes in a metal panel of suitable thickness. Powdered vitreous enamel is inlaid in the holes, suspended in an aqueous organic binder (water-based glue!) and if you are fortunate, remains there due to capillary action. The two contemporaryish examples opposite right are cast in 18k gold and 925 silver respectively as are the two Art Nouveauish pieces below. I'd like to be able to attribute the images below to the copyright owners (if any) but I'm unable to do so - I have no record of where I lifted them from I'm afraid. ED.
Dragonfly ring with diamonds & opals	"Jugendstil" Pendant photo courtesy of Patrick Kapty