This is a miniature version of the axe that Robert the Bruce famously used at the start of the battle of Bannockburn to cleave through the head of the charging English knight De Bohun, and set the mood for the day.
Robert I, King of the Scots (11 July 1274 – 7 June 1329) usually known in modern English as Robert the Bruce (Medieval Gaelic: Roibert a Briuis; modern Scottish Gaelic: Raibeart Bruis; Norman French: Robert de Brus or Robert de Bruys) was King of the Scots from 1306 until his death in 1329.