Eglomise, also known as verre églomisé, is a decorative technique where gold or silver leaf is applied to the back of glass, often engraved or painted, to create a mirrored effect. The term is derived from the French word églomiser, meaning to decorate glass panels by painting on the back. This technique involves applying the leaf to the glass, engraving a design, and then backing it with another layer of glass or foil.