Friday, 27 July 2012
When trading in silver or gold, it is important that the precious metal is of a good quality. In the Viking period, silver could be debased with copper or lead. Alternatively, base-metal objects might be plated in silver or superficially surface enriched to give a deceptive silvery appearance. In order to expose these fakes and debasements, the Vikings developed a number of techniques to reveal the purity of silver.
One such technique was 'nicking', in which small knife cuts or notches were made to the edge of an artefact, such as an ingot or arm-ring. Today, these are visible as crescent-shaped marks. On coins, the more usual technique is known as 'pecking': sharp jabs were made to a flat surface with the tip of a knife, resulting in a small curl of metal. Pecking seems to have appeared in England in the ninth century, as a response to the mixed quality of coinage encountered by the Vikings.
In both cases, the technique was designed to expose plated or enriched forgeries and/ or to test the purity of the silver. If the resistance felt to the nicks and pecks was too soft, there was a chance that lead had been added; too hard, and too much copper might be present. This was also the rationale behind one further testing technique: hammering out a silver item into a thin strip. Since it would take quite a lot of experience and skill to be able to judge accurately the 'right' feel of a peck or nick, these techniques were probably carried out by specialists.
Some items from Viking hoards have huge numbers of nicks or pecks, such as this cut silver ingot. Why would a single artefact have acquired so many nicks? Was it suspicious? And why would somebody test an artefact which had evidently been tested multiple times previously? It's a bit like pressing the button for a lift that has been pressed multiple times before. A study of one of the largest Viking silver hoards has shown that there is no link between the quality of silver in an object, and the number of testing marks it acquired. Perhaps nicking an object was part of a ritual or routine that sealed the end of a transaction: a form of handshake or signature.
A heavily nicked ingot from the National Historical Museum, Stockholm (photo: me, hand: mine )