This single-sided seal shows the earl on horseback to *sinister*, wearing armour, a hauberk and a *coif* of mail. He also has a helmet without nasal, and holds a sword in his right hand and a long kite-shaped shield in his left. The horse has a fringed saddle-cloth and ornamental breast-band.
Image description (reverse)
SIGILLVM HENRICI COMITIS NORTHUMBERLANDIE FILLII REGIS SCOTIE (“Seal of Henry, earl of Northumberland, son of the king of Scotland”).