Ormolu / Gilt Bronze is the gilding technique of applying finely ground, high-carat gold–mercury amalgam to an object of bronze, and for objects finished in this way. The mercury is driven off in a kiln leaving behind a gold coating. The French refer to this technique as “bronze doré”; in English, it is known as “gilt bronze”. Around 1830, legislation in France had outlawed the use of mercury for health reasons, though use continued to the 1900s.
Craftsmen principally used ormolu for the decorative mountings of furniture, clocks, lighting devices, and porcelain. Reference: Wikipedia