It's Irish. EB is Edward Barrett who was active from the end of the seventeenth century until his death in 1722. The hallmark is Dublin and from the letter cycle 1720-1745. The date letter is a little problematical but is either C, E or G (gothic / Old English style) for, respectively, 1722, 1724 or 1726. Barrett's mark is seen up to 1730 as his widow, Mary, continued his business.