When I was first shown this object, LEIC-C5F14A, the shape suggested the Viking age, but the decoration didn’t seem to fit. Enamelling is not what springs to mind on these trefoil mounts, which are usually gilded or plain bronze. Luckily I showed an image to Dr Barry Ager at the British Museum.
He informed me that the glass inlay was unusual though it did have a parallel with a fragmentary trefoil mount, probably from a sword-belt, having been found at Maastricht-Amby in the Netherlands.
It is thought that this may be the only complete example known, it is certainly the first of its type found in England.
The trefoil mounts are of continental origin and broadly dateable to the 9th century. It is a moot point whether they were brought into this country in connection with Viking activity, or were imported directly from France and/or the Low Countries.
Either way, this object is stunning and is a valuable addition to the corpus of Early Medieval finds in the county.