The accurate weighing of hack-silver and gold was critical for the operation of the Viking bullion economy. In order to check the value of bullion being exchanged, Viking traders weighed the bullion with hand-held balances and small lead or copper-alloy weights. In England, one type of weight associated with Viking activity is a lead weight with inset metalwork. These weights are not included in hoards, but they are among recent metal-detector finds, with some being found at market places and urban sites in presumed commercial contexts.
The inset metalwork is usually just a small fragment, which has been taken from a larger object. Sometimes this can be recognised as culturally Scandinavian –the fragment might derive from a Scandinavian oval brooch, for instance. But it is much more common for the metalwork to have an Insular background (that is, it was made in the British Isles or Ireland). Often the metalwork contains enamel, or decorative interlace schemes, both of which were popular Insular art forms.
Lead weight with inset Insular metalwork, found in Norfolk
(image courtesy of the Portable Antiquities Scheme 'Find ID' NMS-03F926)
Usually the metalwork was cut rather haphazardly, although in some cases a complete object was used (e.g. a complete strap-slide, as in the picture below). It may seem odd that bullion weights could incorporate metal fragments of varying size and weight whilst maintaining a weight standard, but in most cases the metal fragments will have contributed only slightly to the overall mass of the weight. Moreover, since the lead was usually shaped to fit the mount, it is clear that weights were fashioned with specific metalwork pieces in mind.
A lead weight incorporating an Insular belt-slide, found in Cumbria and recorded by the Portable Antiquities Scheme (PAS 'Find-ID' LANCUM-683C84)
The reason why metalwork was re-used in lead weights in this way is unclear. It seems unlikely that it was for aesthetic purposes – some of the weights are not exactly attractive. Another possibility is that the metalwork served to personalise weights, allowing the owner to easily recognise their set in a trading environment where multiple sets of weights were in use. This would mean that the owner of the weights could trust his or her own set, and thereby guard against fraud in a transaction. The discovery of multiple weights in graves, for instance, in the Scandinavian boat-burial from Kiloran Bay, Colonsay, supports the idea of individual ownership of weight sets.
But why re-use Insular metalwork in particular? It seems clear that this type of weight first emerged in England, soon after the cessation of Viking raids on Ireland and the west coast of Scotland. These raids generated wealth for the Vikings, often in the form of bullion. It may be that Insular metalwork held symbolic value, serving as a visual reminder of the source of Scandinavian wealth in precisely the contexts when bullion was being exchanged.