This is a bronze medieval seal in the classic ‘Chess Man’ shape. The design shows a squirrel secreting nuts. The Legend reads reads 'I CRAKE NOTIS' meaning 'I crack nuts'. According to Harvey and McGuiness' 1996 'A Guide to British Medieval Seals', the squirrel motif and legend could possibly be associated with "sexual conquest" as red squirrels were sometimes seen in medieval art as women's familiars (p.89).
A similar seal is shown in ‘Medieval Artefacts’ by Nigel Mills.
