Bronze disease

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Bronze disease is an irreversible and nearly inexorable corrosion process that occurs when chlorides come into contact with bronze or other copper-bearing alloys. It can occur as either a dark green coating or a much lighter whitish fuzzy or furry green coating. It is not a bacterial infection, but the result of a chemical reaction with the chlorides that usually occurs by contamination of the bronze object by saltwater or burial in specific types of soil where chloride salts are present. If not treated, it may destroy the affected artifact, but treatment is very difficult, costly, and not always effective. Transfer of chlorides from the contaminated artifact to other artifacts can spread the condition.

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