Analysis of grain boundaries in an embrittled ancient silver necklace

Abstract

Abstract Archaeological silver objects are often found to be embrittled to some extent. Using light and scanning electron microscopy techniques, X‐ray diffraction and AES, the causes of this embrittlement were studied on a silver artefact buried for more than 1000 years in soil. This investigation revealed the presence of chlorine, sulphur and carbon at grain boundaries of the Ag–Cu based object suggesting that most likely; the substantial embrittlement is caused by an inter‐crystalline corrosion attack. The role of copper enrichment at the grain boundaries as a possible path of preferential corrosion attack is discussed. Copyright © 2008 John Wiley & Sons, Ltd.