bronze

Alloy of copper and tin, yellow or brown in colour. It is harder than pure copper, more suitable for casting, and also resists corrosion. Bronze may contain as much as 25% tin, together with small amounts of other metals, mainly lead.

Bronze is one of the first metallic alloys known and used widely by early peoples during the period of history known as the Bronze Age. The first bronze objects date from 3000 BC.

Bell metal, the bronze used for casting bells, contains 15% or more tin. Phosphor bronze is hardened by the addition of a small percentage of phosphorus. Silicon bronze (for telegraph wires) and aluminium bronze are similar alloys of copper with silicon or aluminium and small amounts of iron, nickel, or manganese, but usually no tin.

bronze

In sculpture, a work cast in bronze. An alloy of copper and tin, bronze is harder than copper and, therefore, more suitable for casting. Ancient bronzes develop a patina, a thin green coating caused by oxidation, usually after exposure to air. When bronze is gilded (covered with gold), it is often described as ormolu, although this term strictly refers to a gold-coloured alloy of bronze, zinc, and tin.

Some of the highest-quality bronzes were achieved by ancient Greek and Chinese sculptors, but after the fall of the Roman Empire in the 5th century AD, the expertise of bronze casting was largely lost. The tradition was not truly revived until the Renaissance.