Client: rupertharris

Location: Glossary

The production of patterns on a surface by the use of a corrosive chemical agent. Etching may occur naturally during burial, or may be intentional, e.g., in the finishing treatment of steel, a chemical solution, usually acidic, may be applied to bring out different structures in the steel by preferential removal or colouring of one constituent in order to achieve a surface pattern or design. Etching is also a technique used in the microscopic examination of metals to reveal structural features. (See 'Watered steel').