Corinthian bronze

Corinthian bronze, also called Corinthian brass or æs Corinthiacum, was a highly valuable metal alloy in classical antiquity. It is thought to be an alloy of copper with gold or silver (or both), although it has also been contended that it was simply a very high grade of bronze, or a kind of bronze that was manufactured in Corinth. It is referred to in various ancient texts, but no known examples of Corinthian bronze exist today.

Of the known types of bronze or brass, not distinguished in classical antiquity and interchangeably known in Latin as aes and in Greek as χαλκός, Corinthian bronze was the most valuable. Statues, vases and vessels, or other objects formed of this metal were priceless, of greater value than if they had been made of silver or gold.Pliny the Elder distinguished it into three kinds, depending on the metal that is added to the copper base: in the first, gold is added (luteum); in the second, silver (candidum); in the third, gold, silver, and copper are equally blended.Plutarch and Cicero both comment that Corinthian bronze, unlike many other copper alloys, is resistant to tarnishing. Pliny also refers to a fourth, dark alloy, known as hepatizon.

According to legend, Corinthian bronze was first created by accident, during the burning of Corinth by Lucius Mummius Achaicus in 146 BC, when the city's immense quantities of gold, silver, and copper melted together. Pliny however, remarked that this story is unbelievable, because most of the creators of the highly valued works in Corinthian bronze in Ancient Greece lived at a much earlier period than second century BC. According to Pliny, the method of making it had been lost for a long time, although some sources describe the process by which it is created, involving heat treatment, quenching, leaching, and burnishing, in a process similar to depletion gilding. The lost ability to give an object made from bronze the appearance of gold or silver may be one strand behind the later alchemical quest to turn base metals into precious metals.

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