Gilt bronze
Gilt bronze is bronze, or often copper, coated with a thin layer of gold. In the classic method, fire gilding, an amalgam of gold and mercury was brushed on and heated until the mercury was driven off, leaving the gold bonded to the metal. Gilt bronze is found across Eurasia from antiquity, and in Chinese art it was always more common than silver gilt, the opposite of Europe.
Definition
In fire gilding, also called mercury gilding or wash gilding, gold is reduced to thin plates or grains, heated red-hot and added to hot mercury until it is absorbed; the proportion of mercury to gold is generally six or eight to one. The amalgam is applied to the clean metal surface and the piece is heated, so that the mercury evaporates and leaves a film of gold. In Europe the same work in later centuries is called ormolu, from the French for ground gold; for objects before the 18th century, English uses gilt bronze. The process was dangerous to the gilder, and France banned the use of mercury around 1830, although it continued in use until about 1900. Electroplating, from the mid-19th century, has largely replaced it.
Origin
In our handling, most of the gilt metal that reaches our shelf is Buddhist: figures and censers from China, Tibet, Korea and Japan. Our guide to gilt surfaces on Japanese Buddhist statues sets out the Japanese side.
Other ways of gilding
Fire gilding is one of several methods. Gold leaf can be applied by hand and glued; chemical gilding and electroplating, also called gold plating, deposit gold without mercury. A piece gilded only over part of its surface is called parcel-gilt. Where metal is gilded, the metal below was traditionally silver in the West, giving silver-gilt or vermeil, while gilt bronze was common in China. In our reading, the method matters to a collector because it helps to date a piece: an even, bright modern plating over a supposedly old figure is a reason for caution.
Key facts
| Method | Fire gilding with a gold and mercury amalgam |
|---|---|
| Ratio | Mercury to gold, generally six or eight to one |
| European name | Ormolu, for later pieces |
| In China | More common than silver gilt |
| Replaced by | Electroplating, from the mid-19th century |
How to identify it
- The gold. Fire gilding is thin and follows every detail of the casting; in our handling, it wears first on high points such as the face, knees and hands.
- The metal below. Where the gold has worn, bronze or copper shows through, often with green or red corrosion.
- Gilt copper. Many Himalayan and later Chinese figures are of gilt copper rather than bronze, and we say which where it can be read.
- Base. In our handling, Buddhist figures often have a base plate, sometimes sealed; we report whether it is present and intact.
- Attribution. Dates and dynasties are given as the title states, with "offered as" where an attribution came with the piece.
Where it appears in the collection
Examples include a large gilt-bronze Water-Moon Guanyin, a seated gilt-bronze Buddha and a monumental gilt-bronze Vajrakilaya, on the Asian antiques shelf; our guide to karamono explains how we title them.
Related entries
- Cloisonné: the enamel often combined with gilding
- Reign mark: the mark on many gilt objects
- Kōro: the incense burner
Sources
- Ormolu, encyclopaedia entry, for gilt bronze, the method, the French ban, electroplating and gilt bronze in Chinese art. wikipedia.org
- Gilding, encyclopaedia entry, for fire gilding, the amalgam, the ratio of mercury to gold, other methods, parcel-gilt and silver-gilt. wikipedia.org
Last reviewed 15 November 2026. The Japonista Curation and Concierge Team, Tokyo, Japan.