An Early Medieval (Anglo-Scandinavian) copper-alloy disc brooch with in-laid glass, cloisonné enamel (late 10th – 11th century).
See Buckton, David. 1985. Late 10th-and 11th-century cloisonne enamel brooches. Medieval Archaeology.
Weetch (2013) Type 20 "hybrid"
See SF-16D477 for a much less complete example on www.finds.org.uk with its "central wavy cross saltire in dark blue glass"