Commonwealth 1656 Unite, extremely rare date

Commonwealth (1649-60),gold Unite of Twenty Shillings, 1656, English shield within 15 leaf laurel and palm branch, legends in English language, initial mark sun, THE. COMMONWEALTH. OF. ENGLAND.,rev.English and Irish shields, value .XX. above, beaded circle and legend surrounding, date at top, .GOD. WITH. VS., weight 8.90g (Schneider -/344; Bull EGC 29 R4; N.2715; S.3208).Once cleaned, with some residual toning in parts of legend and in shield hatching, raised die flaws on reverse matching with the Schneider example reverse, surface marks and striations, otherwise very fine and extremely rare with approximately ten examples known of this date and the first we have ever offered for sale, extremely rare.