Keywords:

Abstract:

Electrolytic polishing has been used for some years in industry for metallographic examination. Normal abrasive polishing necessitates a tedious routine of rubbing with successively finer grades of abrasive, and consequently some local destruction of the object examined. Electrolytic polishing requires only a quick preliminary abrasion. This is followed by the use of an electrolytic polishing probe acting as a cathode, the object itself being the anode. The area polished may be limited to a few square millimeters, and polishing takes a minute or so. Where the polished surface cannot be examined in situ, a plastic replica is taken of it. These methods have been used with success in archaeology. The author describes their use in the examination of old iron weapons, and in the identification of fake bronzes and coins. It is also possible to discover a good deal about the penetration of corrosion. Garry Thomson